A chronic generalized bi-directional brain-machine interface.

PubMed

Rouse, A G; Stanslaski, S R; Cong, P; Jensen, R M; Afshar, P; Ullestad, D; Gupta, R; Molnar, G F; Moran, D W; Denison, T J

2011-06-01

A bi-directional neural interface (NI) system was designed and prototyped by incorporating a novel neural recording and processing subsystem into a commercial neural stimulator architecture. The NI system prototype leverages the system infrastructure from an existing neurostimulator to ensure reliable operation in a chronic implantation environment. In addition to providing predicate therapy capabilities, the device adds key elements to facilitate chronic research, such as four channels of electrocortigram/local field potential amplification and spectral analysis, a three-axis accelerometer, algorithm processing, event-based data logging, and wireless telemetry for data uploads and algorithm/configuration updates. The custom-integrated micropower sensor and interface circuits facilitate extended operation in a power-limited device. The prototype underwent significant verification testing to ensure reliability, and meets the requirements for a class CF instrument per IEC-60601 protocols. The ability of the device system to process and aid in classifying brain states was preclinically validated using an in vivo non-human primate model for brain control of a computer cursor (i.e. brain-machine interface or BMI). The primate BMI model was chosen for its ability to quantitatively measure signal decoding performance from brain activity that is similar in both amplitude and spectral content to other biomarkers used to detect disease states (e.g. Parkinson's disease). A key goal of this research prototype is to help broaden the clinical scope and acceptance of NI techniques, particularly real-time brain state detection. These techniques have the potential to be generalized beyond motor prosthesis, and are being explored for unmet needs in other neurological conditions such as movement disorders, stroke and epilepsy.

Upper Body-Based Power Wheelchair Control Interface for Individuals with Tetraplegia

PubMed Central

Thorp, Elias B.; Abdollahi, Farnaz; Chen, David; Farshchiansadegh, Ali; Lee, Mei-Hua; Pedersen, Jessica; Pierella, Camilla; Roth, Elliot J.; Gonzalez, Ismael Seanez; Mussa-Ivaldi, Ferdinando A.

2016-01-01

Many power wheelchair control interfaces are not sufficient for individuals with severely limited upper limb mobility. The majority of controllers that do not rely on coordinated arm and hand movements provide users a limited vocabulary of commands and often do not take advantage of the user’s residual motion. We developed a body-machine interface (BMI) that leverages the flexibility and customizability of redundant control by using high dimensional changes in shoulder kinematics to generate proportional controls commands for a power wheelchair. In this study, three individuals with cervical spinal cord injuries were able to control the power wheelchair safely and accurately using only small shoulder movements. With the BMI, participants were able to achieve their desired trajectories and, after five sessions driving, were able to achieve smoothness that was similar to the smoothness with their current joystick. All participants were twice as slow using the BMI however improved with practice. Importantly, users were able to generalize training controlling a computer to driving a power wheelchair, and employed similar strategies when controlling both devices. Overall, this work suggests that the BMI can be an effective wheelchair control interface for individuals with high-level spinal cord injuries who have limited arm and hand control. PMID:26054071

Brain-machine interfaces: electrophysiological challenges and limitations.

PubMed

Lega, Bradley C; Serruya, Mijail D; Zaghloul, Kareem A

2011-01-01

Brain-machine interfaces (BMI) seek to directly communicate with the human nervous system in order to diagnose and treat intrinsic neurological disorders. While the first generation of these devices has realized significant clinical successes, they often rely on gross electrical stimulation using empirically derived parameters through open-loop mechanisms of action that are not yet fully understood. Their limitations reflect the inherent challenge in developing the next generation of these devices. This review identifies lessons learned from the first generation of BMI devices (chiefly deep brain stimulation), identifying key problems for which the solutions will aid the development of the next generation of technologies. Our analysis examines four hypotheses for the mechanism by which brain stimulation alters surrounding neurophysiologic activity. We then focus on motor prosthetics, describing various approaches to overcoming the problems of decoding neural signals. We next turn to visual prosthetics, an area for which the challenges of signal coding to match neural architecture has been partially overcome. Finally, we close with a review of cortical stimulation, examining basic principles that will be incorporated into the design of future devices. Throughout the review, we relate the issues of each specific topic to the common thread of BMI research: translating new knowledge of network neuroscience into improved devices for neuromodulation.

My thoughts through a robot's eyes: an augmented reality-brain-machine interface.

PubMed

Kansaku, Kenji; Hata, Naoki; Takano, Kouji

2010-02-01

A brain-machine interface (BMI) uses neurophysiological signals from the brain to control external devices, such as robot arms or computer cursors. Combining augmented reality with a BMI, we show that the user's brain signals successfully controlled an agent robot and operated devices in the robot's environment. The user's thoughts became reality through the robot's eyes, enabling the augmentation of real environments outside the anatomy of the human body.

Developments in brain-machine interfaces from the perspective of robotics.

PubMed

Kim, Hyun K; Park, Shinsuk; Srinivasan, Mandayam A

2009-04-01

Many patients suffer from the loss of motor skills, resulting from traumatic brain and spinal cord injuries, stroke, and many other disabling conditions. Thanks to technological advances in measuring and decoding the electrical activity of cortical neurons, brain-machine interfaces (BMI) have become a promising technology that can aid paralyzed individuals. In recent studies on BMI, robotic manipulators have demonstrated their potential as neuroprostheses. Restoring motor skills through robot manipulators controlled by brain signals may improve the quality of life of people with disability. This article reviews current robotic technologies that are relevant to BMI and suggests strategies that could improve the effectiveness of a brain-operated neuroprosthesis through robotics.

Wireless brain-machine interface using EEG and EOG: brain wave classification and robot control

NASA Astrophysics Data System (ADS)

Oh, Sechang; Kumar, Prashanth S.; Kwon, Hyeokjun; Varadan, Vijay K.

2012-04-01

A brain-machine interface (BMI) links a user's brain activity directly to an external device. It enables a person to control devices using only thought. Hence, it has gained significant interest in the design of assistive devices and systems for people with disabilities. In addition, BMI has also been proposed to replace humans with robots in the performance of dangerous tasks like explosives handling/diffusing, hazardous materials handling, fire fighting etc. There are mainly two types of BMI based on the measurement method of brain activity; invasive and non-invasive. Invasive BMI can provide pristine signals but it is expensive and surgery may lead to undesirable side effects. Recent advances in non-invasive BMI have opened the possibility of generating robust control signals from noisy brain activity signals like EEG and EOG. A practical implementation of a non-invasive BMI such as robot control requires: acquisition of brain signals with a robust wearable unit, noise filtering and signal processing, identification and extraction of relevant brain wave features and finally, an algorithm to determine control signals based on the wave features. In this work, we developed a wireless brain-machine interface with a small platform and established a BMI that can be used to control the movement of a robot by using the extracted features of the EEG and EOG signals. The system records and classifies EEG as alpha, beta, delta, and theta waves. The classified brain waves are then used to define the level of attention. The acceleration and deceleration or stopping of the robot is controlled based on the attention level of the wearer. In addition, the left and right movements of eye ball control the direction of the robot.

Cortical and subcortical mechanisms of brain-machine interfaces.

PubMed

Marchesotti, Silvia; Martuzzi, Roberto; Schurger, Aaron; Blefari, Maria Laura; Del Millán, José R; Bleuler, Hannes; Blanke, Olaf

2017-06-01

Technical advances in the field of Brain-Machine Interfaces (BMIs) enable users to control a variety of external devices such as robotic arms, wheelchairs, virtual entities and communication systems through the decoding of brain signals in real time. Most BMI systems sample activity from restricted brain regions, typically the motor and premotor cortex, with limited spatial resolution. Despite the growing number of applications, the cortical and subcortical systems involved in BMI control are currently unknown at the whole-brain level. Here, we provide a comprehensive and detailed report of the areas active during on-line BMI control. We recorded functional magnetic resonance imaging (fMRI) data while participants controlled an EEG-based BMI inside the scanner. We identified the regions activated during BMI control and how they overlap with those involved in motor imagery (without any BMI control). In addition, we investigated which regions reflect the subjective sense of controlling a BMI, the sense of agency for BMI-actions. Our data revealed an extended cortical-subcortical network involved in operating a motor-imagery BMI. This includes not only sensorimotor regions but also the posterior parietal cortex, the insula and the lateral occipital cortex. Interestingly, the basal ganglia and the anterior cingulate cortex were involved in the subjective sense of controlling the BMI. These results inform basic neuroscience by showing that the mechanisms of BMI control extend beyond sensorimotor cortices. This knowledge may be useful for the development of BMIs that offer a more natural and embodied feeling of control for the user. Hum Brain Mapp 38:2971-2989, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

ERD-based online brain-machine interfaces (BMI) in the context of neurorehabilitation: optimizing BMI learning and performance.

PubMed

Soekadar, Surjo R; Witkowski, Matthias; Mellinger, Jürgen; Ramos, Ander; Birbaumer, Niels; Cohen, Leonardo G

2011-10-01

Event-related desynchronization (ERD) of sensori-motor rhythms (SMR) can be used for online brain-machine interface (BMI) control, but yields challenges related to the stability of ERD and feedback strategy to optimize BMI learning.Here, we compared two approaches to this challenge in 20 right-handed healthy subjects (HS, five sessions each, S1-S5) and four stroke patients (SP, 15 sessions each, S1-S15). ERD was recorded from a 275-sensor MEG system. During daily training,motor imagery-induced ERD led to visual and proprioceptive feedback delivered through an orthotic device attached to the subjects' hand and fingers. Group A trained with a heterogeneous reference value (RV) for ERD detection with binary feedback and Group B with a homogenous RV and graded feedback (10 HS and 2 SP in each group). HS in Group B showed better BMI performance than Group A (p < 0.001) and improved BMI control from S1 to S5 (p = 0.012) while Group A did not. In spite of the small n, SP in Group B showed a trend for a higher BMI performance (p = 0.06) and learning was significantly better (p < 0.05). Using a homogeneous RV and graded feedback led to improved modulation of ipsilesional activity resulting in superior BMI learning relative to use of a heterogeneous RV and binary feedback.

Improving brain-machine interface performance by decoding intended future movements

NASA Astrophysics Data System (ADS)

Willett, Francis R.; Suminski, Aaron J.; Fagg, Andrew H.; Hatsopoulos, Nicholas G.

2013-04-01

Objective. A brain-machine interface (BMI) records neural signals in real time from a subject's brain, interprets them as motor commands, and reroutes them to a device such as a robotic arm, so as to restore lost motor function. Our objective here is to improve BMI performance by minimizing the deleterious effects of delay in the BMI control loop. We mitigate the effects of delay by decoding the subject's intended movements a short time lead in the future. Approach. We use the decoded, intended future movements of the subject as the control signal that drives the movement of our BMI. This should allow the user's intended trajectory to be implemented more quickly by the BMI, reducing the amount of delay in the system. In our experiment, a monkey (Macaca mulatta) uses a future prediction BMI to control a simulated arm to hit targets on a screen. Main Results. Results from experiments with BMIs possessing different system delays (100, 200 and 300 ms) show that the monkey can make significantly straighter, faster and smoother movements when the decoder predicts the user's future intent. We also characterize how BMI performance changes as a function of delay, and explore offline how the accuracy of future prediction decoders varies at different time leads. Significance. This study is the first to characterize the effects of control delays in a BMI and to show that decoding the user's future intent can compensate for the negative effect of control delay on BMI performance.

Applications of Brain–Machine Interface Systems in Stroke Recovery and Rehabilitation

PubMed Central

Francisco, Gerard E.; Contreras-Vidal, Jose L.

2014-01-01

Stroke is a leading cause of disability, significantly impacting the quality of life (QOL) in survivors, and rehabilitation remains the mainstay of treatment in these patients. Recent engineering and technological advances such as brain-machine interfaces (BMI) and robotic rehabilitative devices are promising to enhance stroke neu-rorehabilitation, to accelerate functional recovery and improve QOL. This review discusses the recent applications of BMI and robotic-assisted rehabilitation in stroke patients. We present the framework for integrated BMI and robotic-assisted therapies, and discuss their potential therapeutic, assistive and diagnostic functions in stroke rehabilitation. Finally, we conclude with an outlook on the potential challenges and future directions of these neurotechnologies, and their impact on clinical rehabilitation. PMID:25110624

Braided Multi-Electrode Probes (BMEPs) for Neural Interfaces

NASA Astrophysics Data System (ADS)

Kim, Tae Gyo

Although clinical use of invasive neural interfaces is very limited, due to safety and reliability concerns, the potential benefits of their use in brain machine interfaces (BMIs) seem promising and so they have been widely used in the research field. Microelectrodes as invasive neural interfaces are the core tool to record neural activities and their failure is a critical issue for BMI systems. Possible sources of this failure are neural tissue motions and their interactions with stiff electrode arrays or probes fixed to the skull. To overcome these tissue motion problems, we have developed novel braided multi-electrode probes (BMEPs). By interweaving ultra-fine wires into a tubular braid structure, we obtained a highly flexible multi-electrode probe. In this thesis we described BMEP designs and how to fabricate BMEPs, and explore experiments to show the advantages of BMEPs through a mechanical compliance comparison and a chronic immunohistological comparison with single 50microm nichrome wires used as a reference electrode type. Results from the mechanical compliance test showed that the bodies of BMEPs have 4 to 21 times higher compliance than the single 50microm wire and the tethers of BMEPs were 6 to 96 times higher compliance, depending on combinations of the wire size (9.6microm or 12.7microm), the wire numbers (12 or 24), and the length of tether (3, 5 or 10 mm). Results from the immunohistological comparison showed that both BMEPs and 50microm wires anchored to the skull caused stronger tissue reactions than unanchored BMEPs and 50microm wires, and 50microm wires caused stronger tissue reactions than BMEPs. In in-vivo tests with BMEPs, we succeeded in chronic recordings from the spinal cord of freely jumping frogs and in acute recordings from the spinal cord of decerebrate rats during air stepping which was evoked by mesencephalic locomotor region (MLR) stimulation. This technology may provide a stable and reliable neural interface to spinal cord researches with freely moving animals as well as to BMI researches. In addition this is extensible to various applications.

Volitional enhancement of firing synchrony and oscillation by neuronal operant conditioning: interaction with neurorehabilitation and brain-machine interface

PubMed Central

Sakurai, Yoshio; Song, Kichan; Tachibana, Shota; Takahashi, Susumu

2014-01-01

In this review, we focus on neuronal operant conditioning in which increments in neuronal activities are directly rewarded without behaviors. We discuss the potential of this approach to elucidate neuronal plasticity for enhancing specific brain functions and its interaction with the progress in neurorehabilitation and brain-machine interfaces. The key to-be-conditioned activities that this paper emphasizes are synchronous and oscillatory firings of multiple neurons that reflect activities of cell assemblies. First, we introduce certain well-known studies on neuronal operant conditioning in which conditioned enhancements of neuronal firing were reported in animals and humans. These studies demonstrated the feasibility of volitional control over neuronal activity. Second, we refer to the recent studies on operant conditioning of synchrony and oscillation of neuronal activities. In particular, we introduce a recent study showing volitional enhancement of oscillatory activity in monkey motor cortex and our study showing selective enhancement of firing synchrony of neighboring neurons in rat hippocampus. Third, we discuss the reasons for emphasizing firing synchrony and oscillation in neuronal operant conditioning, the main reason being that they reflect the activities of cell assemblies, which have been suggested to be basic neuronal codes representing information in the brain. Finally, we discuss the interaction of neuronal operant conditioning with neurorehabilitation and brain-machine interface (BMI). We argue that synchrony and oscillation of neuronal firing are the key activities required for developing both reliable neurorehabilitation and high-performance BMI. Further, we conclude that research of neuronal operant conditioning, neurorehabilitation, BMI, and system neuroscience will produce findings applicable to these interrelated fields, and neuronal synchrony and oscillation can be a common important bridge among all of them. PMID:24567704

Volitional enhancement of firing synchrony and oscillation by neuronal operant conditioning: interaction with neurorehabilitation and brain-machine interface.

PubMed

Sakurai, Yoshio; Song, Kichan; Tachibana, Shota; Takahashi, Susumu

2014-01-01

In this review, we focus on neuronal operant conditioning in which increments in neuronal activities are directly rewarded without behaviors. We discuss the potential of this approach to elucidate neuronal plasticity for enhancing specific brain functions and its interaction with the progress in neurorehabilitation and brain-machine interfaces. The key to-be-conditioned activities that this paper emphasizes are synchronous and oscillatory firings of multiple neurons that reflect activities of cell assemblies. First, we introduce certain well-known studies on neuronal operant conditioning in which conditioned enhancements of neuronal firing were reported in animals and humans. These studies demonstrated the feasibility of volitional control over neuronal activity. Second, we refer to the recent studies on operant conditioning of synchrony and oscillation of neuronal activities. In particular, we introduce a recent study showing volitional enhancement of oscillatory activity in monkey motor cortex and our study showing selective enhancement of firing synchrony of neighboring neurons in rat hippocampus. Third, we discuss the reasons for emphasizing firing synchrony and oscillation in neuronal operant conditioning, the main reason being that they reflect the activities of cell assemblies, which have been suggested to be basic neuronal codes representing information in the brain. Finally, we discuss the interaction of neuronal operant conditioning with neurorehabilitation and brain-machine interface (BMI). We argue that synchrony and oscillation of neuronal firing are the key activities required for developing both reliable neurorehabilitation and high-performance BMI. Further, we conclude that research of neuronal operant conditioning, neurorehabilitation, BMI, and system neuroscience will produce findings applicable to these interrelated fields, and neuronal synchrony and oscillation can be a common important bridge among all of them.

Brain-machine interfaces for assistive smart homes: A feasibility study with wearable near-infrared spectroscopy.

PubMed

Ogawa, Takeshi; Hirayama, Jun-Ichiro; Gupta, Pankaj; Moriya, Hiroki; Yamaguchi, Shumpei; Ishikawa, Akihiro; Inoue, Yoshihiro; Kawanabe, Motoaki; Ishii, Shin

2015-08-01

Smart houses for elderly or physically challenged people need a method to understand residents' intentions during their daily-living behaviors. To explore a new possibility, we here developed a novel brain-machine interface (BMI) system integrated with an experimental smart house, based on a prototype of a wearable near-infrared spectroscopy (NIRS) device, and verified the system in a specific task of controlling of the house's equipments with BMI. We recorded NIRS signals of three participants during typical daily-living actions (DLAs), and classified them by linear support vector machine. In our off-line analysis, four DLAs were classified at about 70% mean accuracy, significantly above the chance level of 25%, in every participant. In an online demonstration in the real smart house, one participant successfully controlled three target appliances by BMI at 81.3% accuracy. Thus we successfully demonstrated the feasibility of using NIRS-BMI in real smart houses, which will possibly enhance new assistive smart-home technologies.

Design and Optimization of an EEG-Based Brain Machine Interface (BMI) to an Upper-Limb Exoskeleton for Stroke Survivors

PubMed Central

Bhagat, Nikunj A.; Venkatakrishnan, Anusha; Abibullaev, Berdakh; Artz, Edward J.; Yozbatiran, Nuray; Blank, Amy A.; French, James; Karmonik, Christof; Grossman, Robert G.; O'Malley, Marcia K.; Francisco, Gerard E.; Contreras-Vidal, Jose L.

2016-01-01

This study demonstrates the feasibility of detecting motor intent from brain activity of chronic stroke patients using an asynchronous electroencephalography (EEG)-based brain machine interface (BMI). Intent was inferred from movement related cortical potentials (MRCPs) measured over an optimized set of EEG electrodes. Successful intent detection triggered the motion of an upper-limb exoskeleton (MAHI Exo-II), to guide movement and to encourage active user participation by providing instantaneous sensory feedback. Several BMI design features were optimized to increase system performance in the presence of single-trial variability of MRCPs in the injured brain: (1) an adaptive time window was used for extracting features during BMI calibration; (2) training data from two consecutive days were pooled for BMI calibration to increase robustness to handle the day-to-day variations typical of EEG, and (3) BMI predictions were gated by residual electromyography (EMG) activity from the impaired arm, to reduce the number of false positives. This patient-specific BMI calibration approach can accommodate a broad spectrum of stroke patients with diverse motor capabilities. Following BMI optimization on day 3, testing of the closed-loop BMI-MAHI exoskeleton, on 4th and 5th days of the study, showed consistent BMI performance with overall mean true positive rate (TPR) = 62.7 ± 21.4% on day 4 and 67.1 ± 14.6% on day 5. The overall false positive rate (FPR) across subjects was 27.74 ± 37.46% on day 4 and 27.5 ± 35.64% on day 5; however for two subjects who had residual motor function and could benefit from the EMG-gated BMI, the mean FPR was quite low (< 10%). On average, motor intent was detected −367 ± 328 ms before movement onset during closed-loop operation. These findings provide evidence that closed-loop EEG-based BMI for stroke patients can be designed and optimized to perform well across multiple days without system recalibration. PMID:27065787

Control of a 2 DoF robot using a brain-machine interface.

PubMed

Hortal, Enrique; Ubeda, Andrés; Iáñez, Eduardo; Azorín, José M

2014-09-01

In this paper, a non-invasive spontaneous Brain-Machine Interface (BMI) is used to control the movement of a planar robot. To that end, two mental tasks are used to manage the visual interface that controls the robot. The robot used is a PupArm, a force-controlled planar robot designed by the nBio research group at the Miguel Hernández University of Elche (Spain). Two control strategies are compared: hierarchical and directional control. The experimental test (performed by four users) consists of reaching four targets. The errors and time used during the performance of the tests are compared in both control strategies (hierarchical and directional control). The advantages and disadvantages of each method are shown after the analysis of the results. The hierarchical control allows an accurate approaching to the goals but it is slower than using the directional control which, on the contrary, is less precise. The results show both strategies are useful to control this planar robot. In the future, by adding an extra device like a gripper, this BMI could be used in assistive applications such as grasping daily objects in a realistic environment. In order to compare the behavior of the system taking into account the opinion of the users, a NASA Tasks Load Index (TLX) questionnaire is filled out after two sessions are completed. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Causal network in a deafferented non-human primate brain.

PubMed

Balasubramanian, Karthikeyan; Takahashi, Kazutaka; Hatsopoulos, Nicholas G

2015-01-01

De-afferented/efferented neural ensembles can undergo causal changes when interfaced to neuroprosthetic devices. These changes occur via recruitment or isolation of neurons, alterations in functional connectivity within the ensemble and/or changes in the role of neurons, i.e., excitatory/inhibitory. In this work, emergence of a causal network and changes in the dynamics are demonstrated for a deafferented brain region exposed to BMI (brain-machine interface) learning. The BMI was controlling a robot for reach-and-grasp behavior. And, the motor cortical regions used for the BMI were deafferented due to chronic amputation, and ensembles of neurons were decoded for velocity control of the multi-DOF robot. A generalized linear model-framework based Granger causality (GLM-GC) technique was used in estimating the ensemble connectivity. Model selection was based on the AIC (Akaike Information Criterion).

A new therapeutic application of brain-machine interface (BMI) training followed by hybrid assistive neuromuscular dynamic stimulation (HANDS) therapy for patients with severe hemiparetic stroke: A proof of concept study.

PubMed

Kawakami, Michiyuki; Fujiwara, Toshiyuki; Ushiba, Junichi; Nishimoto, Atsuko; Abe, Kaoru; Honaga, Kaoru; Nishimura, Atsuko; Mizuno, Katsuhiro; Kodama, Mitsuhiko; Masakado, Yoshihisa; Liu, Meigen

2016-09-21

Hybrid assistive neuromuscular dynamic stimulation (HANDS) therapy improved paretic upper extremity motor function in patients with severe to moderate hemiparesis. We hypothesized that brain machine interface (BMI) training would be able to increase paretic finger muscle activity enough to apply HANDS therapy in patients with severe hemiparesis, whose finger extensor was absent. The aim of this study was to assess the efficacy of BMI training followed by HANDS therapy in patients with severe hemiparesis. Twenty-nine patients with chronic stroke who could not extend their paretic fingers were participated this study. We applied BMI training for 10 days at 40 min per day. The BMI detected the patients' motor imagery of paretic finger extension with event-related desynchronization (ERD) over the affected primary sensorimotor cortex, recorded with electroencephalography. Patients wore a motor-driven orthosis, which extended their paretic fingers and was triggered with ERD. When muscle activity in their paretic fingers was detected with surface electrodes after 10 days of BMI training, we applied HANDS therapy for the following 3 weeks. In HANDS therapy, participants received closed-loop, electromyogram-controlled, neuromuscular electrical stimulation (NMES) combined with a wrist-hand splint for 3 weeks at 8 hours a day. Before BMI training, after BMI training, after HANDS therapy and 3month after HANDS therapy, we assessed Fugl-Meyer Assessment upper extremity motor score (FMA) and the Motor Activity Log14-Amount of Use (MAL-AOU) score. After 10 days of BMI training, finger extensor activity had appeared in 21 patients. Eighteen of 21 patients then participated in 3 weeks of HANDS therapy. We found a statistically significant improvement in the FMA and the MAL-AOU scores after the BMI training, and further improvement was seen after the HANDS therapy. Combining BMI training with HANDS therapy could be an effective therapeutic strategy for severe UE paralysis after stroke.

A Smart Modeling Framework for Integrating BMI-enabled Models as Web Services

NASA Astrophysics Data System (ADS)

Jiang, P.; Elag, M.; Kumar, P.; Peckham, S. D.; Liu, R.; Marini, L.; Hsu, L.

2015-12-01

Serviced-oriented computing provides an opportunity to couple web service models using semantic web technology. Through this approach, models that are exposed as web services can be conserved in their own local environment, thus making it easy for modelers to maintain and update the models. In integrated modeling, the serviced-oriented loose-coupling approach requires (1) a set of models as web services, (2) the model metadata describing the external features of a model (e.g., variable name, unit, computational grid, etc.) and (3) a model integration framework. We present the architecture of coupling web service models that are self-describing by utilizing a smart modeling framework. We expose models that are encapsulated with CSDMS (Community Surface Dynamics Modeling System) Basic Model Interfaces (BMI) as web services. The BMI-enabled models are self-describing by uncovering models' metadata through BMI functions. After a BMI-enabled model is serviced, a client can initialize, execute and retrieve the meta-information of the model by calling its BMI functions over the web. Furthermore, a revised version of EMELI (Peckham, 2015), an Experimental Modeling Environment for Linking and Interoperability, is chosen as the framework for coupling BMI-enabled web service models. EMELI allows users to combine a set of component models into a complex model by standardizing model interface using BMI as well as providing a set of utilities smoothing the integration process (e.g., temporal interpolation). We modify the original EMELI so that the revised modeling framework is able to initialize, execute and find the dependencies of the BMI-enabled web service models. By using the revised EMELI, an example will be presented on integrating a set of topoflow model components that are BMI-enabled and exposed as web services. Reference: Peckham, S.D. (2014) EMELI 1.0: An experimental smart modeling framework for automatic coupling of self-describing models, Proceedings of HIC 2014, 11th International Conf. on Hydroinformatics, New York, NY.

Blending of brain-machine interface and vision-guided autonomous robotics improves neuroprosthetic arm performance during grasping.

PubMed

Downey, John E; Weiss, Jeffrey M; Muelling, Katharina; Venkatraman, Arun; Valois, Jean-Sebastien; Hebert, Martial; Bagnell, J Andrew; Schwartz, Andrew B; Collinger, Jennifer L

2016-03-18

Recent studies have shown that brain-machine interfaces (BMIs) offer great potential for restoring upper limb function. However, grasping objects is a complicated task and the signals extracted from the brain may not always be capable of driving these movements reliably. Vision-guided robotic assistance is one possible way to improve BMI performance. We describe a method of shared control where the user controls a prosthetic arm using a BMI and receives assistance with positioning the hand when it approaches an object. Two human subjects with tetraplegia used a robotic arm to complete object transport tasks with and without shared control. The shared control system was designed to provide a balance between BMI-derived intention and computer assistance. An autonomous robotic grasping system identified and tracked objects and defined stable grasp positions for these objects. The system identified when the user intended to interact with an object based on the BMI-controlled movements of the robotic arm. Using shared control, BMI controlled movements and autonomous grasping commands were blended to ensure secure grasps. Both subjects were more successful on object transfer tasks when using shared control compared to BMI control alone. Movements made using shared control were more accurate, more efficient, and less difficult. One participant attempted a task with multiple objects and successfully lifted one of two closely spaced objects in 92 % of trials, demonstrating the potential for users to accurately execute their intention while using shared control. Integration of BMI control with vision-guided robotic assistance led to improved performance on object transfer tasks. Providing assistance while maintaining generalizability will make BMI systems more attractive to potential users. NCT01364480 and NCT01894802 .

A Brain-Machine-Muscle Interface for Restoring Hindlimb Locomotion after Complete Spinal Transection in Rats

PubMed Central

Alam, Monzurul; Chen, Xi; Zhang, Zicong; Li, Yan; He, Jufang

2014-01-01

A brain-machine interface (BMI) is a neuroprosthetic device that can restore motor function of individuals with paralysis. Although the feasibility of BMI control of upper-limb neuroprostheses has been demonstrated, a BMI for the restoration of lower-limb motor functions has not yet been developed. The objective of this study was to determine if gait-related information can be captured from neural activity recorded from the primary motor cortex of rats, and if this neural information can be used to stimulate paralysed hindlimb muscles after complete spinal cord transection. Neural activity was recorded from the hindlimb area of the primary motor cortex of six female Sprague Dawley rats during treadmill locomotion before and after mid-thoracic transection. Before spinal transection there was a strong association between neural activity and the step cycle. This association decreased after spinal transection. However, the locomotive state (standing vs. walking) could still be successfully decoded from neural recordings made after spinal transection. A novel BMI device was developed that processed this neural information in real-time and used it to control electrical stimulation of paralysed hindlimb muscles. This system was able to elicit hindlimb muscle contractions that mimicked forelimb stepping. We propose this lower-limb BMI as a future neuroprosthesis for human paraplegics. PMID:25084446

A BMI-based occupational therapy assist suit: asynchronous control by SSVEP

PubMed Central

Sakurada, Takeshi; Kawase, Toshihiro; Takano, Kouji; Komatsu, Tomoaki; Kansaku, Kenji

2013-01-01

A brain-machine interface (BMI) is an interface technology that uses neurophysiological signals from the brain to control external machines. Recent invasive BMI technologies have succeeded in the asynchronous control of robot arms for a useful series of actions, such as reaching and grasping. In this study, we developed non-invasive BMI technologies aiming to make such useful movements using the subject's own hands by preparing a BMI-based occupational therapy assist suit (BOTAS). We prepared a pre-recorded series of useful actions—a grasping-a-ball movement and a carrying-the-ball movement—and added asynchronous control using steady-state visual evoked potential (SSVEP) signals. A SSVEP signal was used to trigger the grasping-a-ball movement and another SSVEP signal was used to trigger the carrying-the-ball movement. A support vector machine was used to classify EEG signals recorded from the visual cortex (Oz) in real time. Untrained, able-bodied participants (n = 12) operated the system successfully. Classification accuracy and time required for SSVEP detection were ~88% and 3 s, respectively. We further recruited three patients with upper cervical spinal cord injuries (SCIs); they also succeeded in operating the system without training. These data suggest that our BOTAS system is potentially useful in terms of rehabilitation of patients with upper limb disabilities. PMID:24068982

A brain-machine-muscle interface for restoring hindlimb locomotion after complete spinal transection in rats.

PubMed

Alam, Monzurul; Chen, Xi; Zhang, Zicong; Li, Yan; He, Jufang

2014-01-01

A brain-machine interface (BMI) is a neuroprosthetic device that can restore motor function of individuals with paralysis. Although the feasibility of BMI control of upper-limb neuroprostheses has been demonstrated, a BMI for the restoration of lower-limb motor functions has not yet been developed. The objective of this study was to determine if gait-related information can be captured from neural activity recorded from the primary motor cortex of rats, and if this neural information can be used to stimulate paralysed hindlimb muscles after complete spinal cord transection. Neural activity was recorded from the hindlimb area of the primary motor cortex of six female Sprague Dawley rats during treadmill locomotion before and after mid-thoracic transection. Before spinal transection there was a strong association between neural activity and the step cycle. This association decreased after spinal transection. However, the locomotive state (standing vs. walking) could still be successfully decoded from neural recordings made after spinal transection. A novel BMI device was developed that processed this neural information in real-time and used it to control electrical stimulation of paralysed hindlimb muscles. This system was able to elicit hindlimb muscle contractions that mimicked forelimb stepping. We propose this lower-limb BMI as a future neuroprosthesis for human paraplegics.

A Bidirectional Brain-Machine Interface Featuring a Neuromorphic Hardware Decoder.

PubMed

Boi, Fabio; Moraitis, Timoleon; De Feo, Vito; Diotalevi, Francesco; Bartolozzi, Chiara; Indiveri, Giacomo; Vato, Alessandro

2016-01-01

Bidirectional brain-machine interfaces (BMIs) establish a two-way direct communication link between the brain and the external world. A decoder translates recorded neural activity into motor commands and an encoder delivers sensory information collected from the environment directly to the brain creating a closed-loop system. These two modules are typically integrated in bulky external devices. However, the clinical support of patients with severe motor and sensory deficits requires compact, low-power, and fully implantable systems that can decode neural signals to control external devices. As a first step toward this goal, we developed a modular bidirectional BMI setup that uses a compact neuromorphic processor as a decoder. On this chip we implemented a network of spiking neurons built using its ultra-low-power mixed-signal analog/digital circuits. On-chip on-line spike-timing-dependent plasticity synapse circuits enabled the network to learn to decode neural signals recorded from the brain into motor outputs controlling the movements of an external device. The modularity of the BMI allowed us to tune the individual components of the setup without modifying the whole system. In this paper, we present the features of this modular BMI and describe how we configured the network of spiking neuron circuits to implement the decoder and to coordinate it with the encoder in an experimental BMI paradigm that connects bidirectionally the brain of an anesthetized rat with an external object. We show that the chip learned the decoding task correctly, allowing the interfaced brain to control the object's trajectories robustly. Based on our demonstration, we propose that neuromorphic technology is mature enough for the development of BMI modules that are sufficiently low-power and compact, while being highly computationally powerful and adaptive.

A Bidirectional Brain-Machine Interface Featuring a Neuromorphic Hardware Decoder

PubMed Central

Boi, Fabio; Moraitis, Timoleon; De Feo, Vito; Diotalevi, Francesco; Bartolozzi, Chiara; Indiveri, Giacomo; Vato, Alessandro

2016-01-01

Bidirectional brain-machine interfaces (BMIs) establish a two-way direct communication link between the brain and the external world. A decoder translates recorded neural activity into motor commands and an encoder delivers sensory information collected from the environment directly to the brain creating a closed-loop system. These two modules are typically integrated in bulky external devices. However, the clinical support of patients with severe motor and sensory deficits requires compact, low-power, and fully implantable systems that can decode neural signals to control external devices. As a first step toward this goal, we developed a modular bidirectional BMI setup that uses a compact neuromorphic processor as a decoder. On this chip we implemented a network of spiking neurons built using its ultra-low-power mixed-signal analog/digital circuits. On-chip on-line spike-timing-dependent plasticity synapse circuits enabled the network to learn to decode neural signals recorded from the brain into motor outputs controlling the movements of an external device. The modularity of the BMI allowed us to tune the individual components of the setup without modifying the whole system. In this paper, we present the features of this modular BMI and describe how we configured the network of spiking neuron circuits to implement the decoder and to coordinate it with the encoder in an experimental BMI paradigm that connects bidirectionally the brain of an anesthetized rat with an external object. We show that the chip learned the decoding task correctly, allowing the interfaced brain to control the object's trajectories robustly. Based on our demonstration, we propose that neuromorphic technology is mature enough for the development of BMI modules that are sufficiently low-power and compact, while being highly computationally powerful and adaptive. PMID:28018162

Closed-Loop Hybrid Gaze Brain-Machine Interface Based Robotic Arm Control with Augmented Reality Feedback

PubMed Central

Zeng, Hong; Wang, Yanxin; Wu, Changcheng; Song, Aiguo; Liu, Jia; Ji, Peng; Xu, Baoguo; Zhu, Lifeng; Li, Huijun; Wen, Pengcheng

2017-01-01

Brain-machine interface (BMI) can be used to control the robotic arm to assist paralysis people for performing activities of daily living. However, it is still a complex task for the BMI users to control the process of objects grasping and lifting with the robotic arm. It is hard to achieve high efficiency and accuracy even after extensive trainings. One important reason is lacking of sufficient feedback information for the user to perform the closed-loop control. In this study, we proposed a method of augmented reality (AR) guiding assistance to provide the enhanced visual feedback to the user for a closed-loop control with a hybrid Gaze-BMI, which combines the electroencephalography (EEG) signals based BMI and the eye tracking for an intuitive and effective control of the robotic arm. Experiments for the objects manipulation tasks while avoiding the obstacle in the workspace are designed to evaluate the performance of our method for controlling the robotic arm. According to the experimental results obtained from eight subjects, the advantages of the proposed closed-loop system (with AR feedback) over the open-loop system (with visual inspection only) have been verified. The number of trigger commands used for controlling the robotic arm to grasp and lift the objects with AR feedback has reduced significantly and the height gaps of the gripper in the lifting process have decreased more than 50% compared to those trials with normal visual inspection only. The results reveal that the hybrid Gaze-BMI user can benefit from the information provided by the AR interface, improving the efficiency and reducing the cognitive load during the grasping and lifting processes. PMID:29163123

A confidence metric for using neurobiological feedback in actor-critic reinforcement learning based brain-machine interfaces

PubMed Central

Prins, Noeline W.; Sanchez, Justin C.; Prasad, Abhishek

2014-01-01

Brain-Machine Interfaces (BMIs) can be used to restore function in people living with paralysis. Current BMIs require extensive calibration that increase the set-up times and external inputs for decoder training that may be difficult to produce in paralyzed individuals. Both these factors have presented challenges in transitioning the technology from research environments to activities of daily living (ADL). For BMIs to be seamlessly used in ADL, these issues should be handled with minimal external input thus reducing the need for a technician/caregiver to calibrate the system. Reinforcement Learning (RL) based BMIs are a good tool to be used when there is no external training signal and can provide an adaptive modality to train BMI decoders. However, RL based BMIs are sensitive to the feedback provided to adapt the BMI. In actor-critic BMIs, this feedback is provided by the critic and the overall system performance is limited by the critic accuracy. In this work, we developed an adaptive BMI that could handle inaccuracies in the critic feedback in an effort to produce more accurate RL based BMIs. We developed a confidence measure, which indicated how appropriate the feedback is for updating the decoding parameters of the actor. The results show that with the new update formulation, the critic accuracy is no longer a limiting factor for the overall performance. We tested and validated the system onthree different data sets: synthetic data generated by an Izhikevich neural spiking model, synthetic data with a Gaussian noise distribution, and data collected from a non-human primate engaged in a reaching task. All results indicated that the system with the critic confidence built in always outperformed the system without the critic confidence. Results of this study suggest the potential application of the technique in developing an autonomous BMI that does not need an external signal for training or extensive calibration. PMID:24904257

Decoding position, velocity, or goal: does it matter for brain-machine interfaces?

PubMed

Marathe, A R; Taylor, D M

2011-04-01

Arm end-point position, end-point velocity, and the intended final location or 'goal' of a reach have all been decoded from cortical signals for use in brain-machine interface (BMI) applications. These different aspects of arm movement can be decoded from the brain and used directly to control the position, velocity, or movement goal of a device. However, these decoded parameters can also be remapped to control different aspects of movement, such as using the decoded position of the hand to control the velocity of a device. People easily learn to use the position of a joystick to control the velocity of an object in a videogame. Similarly, in BMI systems, the position, velocity, or goal of a movement could be decoded from the brain and remapped to control some other aspect of device movement. This study evaluates how easily people make transformations between position, velocity, and reach goal in BMI systems. It also evaluates how different amounts of decoding error impact on device control with and without these transformations. Results suggest some remapping options can significantly improve BMI control. This study provides guidance on what remapping options to use when various amounts of decoding error are present.

Decoding position, velocity, or goal: Does it matter for brain-machine interfaces?

NASA Astrophysics Data System (ADS)

Marathe, A. R.; Taylor, D. M.

2011-04-01

Arm end-point position, end-point velocity, and the intended final location or 'goal' of a reach have all been decoded from cortical signals for use in brain-machine interface (BMI) applications. These different aspects of arm movement can be decoded from the brain and used directly to control the position, velocity, or movement goal of a device. However, these decoded parameters can also be remapped to control different aspects of movement, such as using the decoded position of the hand to control the velocity of a device. People easily learn to use the position of a joystick to control the velocity of an object in a videogame. Similarly, in BMI systems, the position, velocity, or goal of a movement could be decoded from the brain and remapped to control some other aspect of device movement. This study evaluates how easily people make transformations between position, velocity, and reach goal in BMI systems. It also evaluates how different amounts of decoding error impact on device control with and without these transformations. Results suggest some remapping options can significantly improve BMI control. This study provides guidance on what remapping options to use when various amounts of decoding error are present.

A high performing brain-machine interface driven by low-frequency local field potentials alone and together with spikes

NASA Astrophysics Data System (ADS)

Stavisky, Sergey D.; Kao, Jonathan C.; Nuyujukian, Paul; Ryu, Stephen I.; Shenoy, Krishna V.

2015-06-01

Objective. Brain-machine interfaces (BMIs) seek to enable people with movement disabilities to directly control prosthetic systems with their neural activity. Current high performance BMIs are driven by action potentials (spikes), but access to this signal often diminishes as sensors degrade over time. Decoding local field potentials (LFPs) as an alternative or complementary BMI control signal may improve performance when there is a paucity of spike signals. To date only a small handful of LFP decoding methods have been tested online; there remains a need to test different LFP decoding approaches and improve LFP-driven performance. There has also not been a reported demonstration of a hybrid BMI that decodes kinematics from both LFP and spikes. Here we first evaluate a BMI driven by the local motor potential (LMP), a low-pass filtered time-domain LFP amplitude feature. We then combine decoding of both LMP and spikes to implement a hybrid BMI. Approach. Spikes and LFP were recorded from two macaques implanted with multielectrode arrays in primary and premotor cortex while they performed a reaching task. We then evaluated closed-loop BMI control using biomimetic decoders driven by LMP, spikes, or both signals together. Main results. LMP decoding enabled quick and accurate cursor control which surpassed previously reported LFP BMI performance. Hybrid decoding of both spikes and LMP improved performance when spikes signal quality was mediocre to poor. Significance. These findings show that LMP is an effective BMI control signal which requires minimal power to extract and can substitute for or augment impoverished spikes signals. Use of this signal may lengthen the useful lifespan of BMIs and is therefore an important step towards clinically viable BMIs.

Brain-machine interfaces in neurorehabilitation of stroke.

PubMed

Soekadar, Surjo R; Birbaumer, Niels; Slutzky, Marc W; Cohen, Leonardo G

2015-11-01

Stroke is among the leading causes of long-term disabilities leaving an increasing number of people with cognitive, affective and motor impairments depending on assistance in their daily life. While function after stroke can significantly improve in the first weeks and months, further recovery is often slow or non-existent in the more severe cases encompassing 30-50% of all stroke victims. The neurobiological mechanisms underlying recovery in those patients are incompletely understood. However, recent studies demonstrated the brain's remarkable capacity for functional and structural plasticity and recovery even in severe chronic stroke. As all established rehabilitation strategies require some remaining motor function, there is currently no standardized and accepted treatment for patients with complete chronic muscle paralysis. The development of brain-machine interfaces (BMIs) that translate brain activity into control signals of computers or external devices provides two new strategies to overcome stroke-related motor paralysis. First, BMIs can establish continuous high-dimensional brain-control of robotic devices or functional electric stimulation (FES) to assist in daily life activities (assistive BMI). Second, BMIs could facilitate neuroplasticity, thus enhancing motor learning and motor recovery (rehabilitative BMI). Advances in sensor technology, development of non-invasive and implantable wireless BMI-systems and their combination with brain stimulation, along with evidence for BMI systems' clinical efficacy suggest that BMI-related strategies will play an increasing role in neurorehabilitation of stroke. Copyright © 2014. Published by Elsevier Inc.

Brain-machine interfaces can accelerate clarification of the principal mysteries and real plasticity of the brain.

PubMed

Sakurai, Yoshio

2014-01-01

This perspective emphasizes that the brain-machine interface (BMI) research has the potential to clarify major mysteries of the brain and that such clarification of the mysteries by neuroscience is needed to develop BMIs. I enumerate five principal mysteries. The first is "how is information encoded in the brain?" This is the fundamental question for understanding what our minds are and is related to the verification of Hebb's cell assembly theory. The second is "how is information distributed in the brain?" This is also a reconsideration of the functional localization of the brain. The third is "what is the function of the ongoing activity of the brain?" This is the problem of how the brain is active during no-task periods and what meaning such spontaneous activity has. The fourth is "how does the bodily behavior affect the brain function?" This is the problem of brain-body interaction, and obtaining a new "body" by a BMI leads to a possibility of changes in the owner's brain. The last is "to what extent can the brain induce plasticity?" Most BMIs require changes in the brain's neuronal activity to realize higher performance, and the neuronal operant conditioning inherent in the BMIs further enhances changes in the activity.

Augmenting intracortical brain-machine interface with neurally driven error detectors

NASA Astrophysics Data System (ADS)

Even-Chen, Nir; Stavisky, Sergey D.; Kao, Jonathan C.; Ryu, Stephen I.; Shenoy, Krishna V.

2017-12-01

Objective. Making mistakes is inevitable, but identifying them allows us to correct or adapt our behavior to improve future performance. Current brain-machine interfaces (BMIs) make errors that need to be explicitly corrected by the user, thereby consuming time and thus hindering performance. We hypothesized that neural correlates of the user perceiving the mistake could be used by the BMI to automatically correct errors. However, it was unknown whether intracortical outcome error signals were present in the premotor and primary motor cortices, brain regions successfully used for intracortical BMIs. Approach. We report here for the first time a putative outcome error signal in spiking activity within these cortices when rhesus macaques performed an intracortical BMI computer cursor task. Main results. We decoded BMI trial outcomes shortly after and even before a trial ended with 96% and 84% accuracy, respectively. This led us to develop and implement in real-time a first-of-its-kind intracortical BMI error ‘detect-and-act’ system that attempts to automatically ‘undo’ or ‘prevent’ mistakes. The detect-and-act system works independently and in parallel to a kinematic BMI decoder. In a challenging task that resulted in substantial errors, this approach improved the performance of a BMI employing two variants of the ubiquitous Kalman velocity filter, including a state-of-the-art decoder (ReFIT-KF). Significance. Detecting errors in real-time from the same brain regions that are commonly used to control BMIs should improve the clinical viability of BMIs aimed at restoring motor function to people with paralysis.

BMI cyberworkstation: enabling dynamic data-driven brain-machine interface research through cyberinfrastructure.

PubMed

Zhao, Ming; Rattanatamrong, Prapaporn; DiGiovanna, Jack; Mahmoudi, Babak; Figueiredo, Renato J; Sanchez, Justin C; Príncipe, José C; Fortes, José A B

2008-01-01

Dynamic data-driven brain-machine interfaces (DDDBMI) have great potential to advance the understanding of neural systems and improve the design of brain-inspired rehabilitative systems. This paper presents a novel cyberinfrastructure that couples in vivo neurophysiology experimentation with massive computational resources to provide seamless and efficient support of DDDBMI research. Closed-loop experiments can be conducted with in vivo data acquisition, reliable network transfer, parallel model computation, and real-time robot control. Behavioral experiments with live animals are supported with real-time guarantees. Offline studies can be performed with various configurations for extensive analysis and training. A Web-based portal is also provided to allow users to conveniently interact with the cyberinfrastructure, conducting both experimentation and analysis. New motor control models are developed based on this approach, which include recursive least square based (RLS) and reinforcement learning based (RLBMI) algorithms. The results from an online RLBMI experiment shows that the cyberinfrastructure can successfully support DDDBMI experiments and meet the desired real-time requirements.

Brain-Machine Interface Enables Bimanual Arm Movements in Monkeys

PubMed Central

Ifft, Peter J.; Shokur, Solaiman; Li, Zheng; Lebedev, Mikhail A.; Nicolelis, Miguel A. L.

2014-01-01

Brain-machine interfaces (BMIs) are artificial systems that aim to restore sensation and movement to severely paralyzed patients. However, previous BMIs enabled only single arm functionality, and control of bimanual movements was a major challenge. Here, we developed and tested a bimanual BMI that enabled rhesus monkeys to control two avatar arms simultaneously. The bimanual BMI was based on the extracellular activity of 374–497 neurons recorded from several frontal and parietal cortical areas of both cerebral hemispheres. Cortical activity was transformed into movements of the two arms with a decoding algorithm called a 5th order unscented Kalman filter (UKF). The UKF is well-suited for BMI decoding because it accounts for both characteristics of reaching movements and their representation by cortical neurons. The UKF was trained either during a manual task performed with two joysticks or by having the monkeys passively observe the movements of avatar arms. Most cortical neurons changed their modulation patterns when both arms were engaged simultaneously. Representing the two arms jointly in a single UKF decoder resulted in improved decoding performance compared with using separate decoders for each arm. As the animals’ performance in bimanual BMI control improved over time, we observed widespread plasticity in frontal and parietal cortical areas. Neuronal representation of the avatar and reach targets was enhanced with learning, whereas pairwise correlations between neurons initially increased and then decreased. These results suggest that cortical networks may assimilate the two avatar arms through BMI control. PMID:24197735

Three-dimensional, automated, real-time video system for tracking limb motion in brain-machine interface studies.

PubMed

Peikon, Ian D; Fitzsimmons, Nathan A; Lebedev, Mikhail A; Nicolelis, Miguel A L

2009-06-15

Collection and analysis of limb kinematic data are essential components of the study of biological motion, including research into biomechanics, kinesiology, neurophysiology and brain-machine interfaces (BMIs). In particular, BMI research requires advanced, real-time systems capable of sampling limb kinematics with minimal contact to the subject's body. To answer this demand, we have developed an automated video tracking system for real-time tracking of multiple body parts in freely behaving primates. The system employs high-contrast markers painted on the animal's joints to continuously track the three-dimensional positions of their limbs during activity. Two-dimensional coordinates captured by each video camera are combined and converted to three-dimensional coordinates using a quadratic fitting algorithm. Real-time operation of the system is accomplished using direct memory access (DMA). The system tracks the markers at a rate of 52 frames per second (fps) in real-time and up to 100fps if video recordings are captured to be later analyzed off-line. The system has been tested in several BMI primate experiments, in which limb position was sampled simultaneously with chronic recordings of the extracellular activity of hundreds of cortical cells. During these recordings, multiple computational models were employed to extract a series of kinematic parameters from neuronal ensemble activity in real-time. The system operated reliably under these experimental conditions and was able to compensate for marker occlusions that occurred during natural movements. We propose that this system could also be extended to applications that include other classes of biological motion.

Soft brain-machine interfaces for assistive robotics: A novel control approach.

PubMed

Schiatti, Lucia; Tessadori, Jacopo; Barresi, Giacinto; Mattos, Leonardo S; Ajoudani, Arash

2017-07-01

Robotic systems offer the possibility of improving the life quality of people with severe motor disabilities, enhancing the individual's degree of independence and interaction with the external environment. In this direction, the operator's residual functions must be exploited for the control of the robot movements and the underlying dynamic interaction through intuitive and effective human-robot interfaces. Towards this end, this work aims at exploring the potential of a novel Soft Brain-Machine Interface (BMI), suitable for dynamic execution of remote manipulation tasks for a wide range of patients. The interface is composed of an eye-tracking system, for an intuitive and reliable control of a robotic arm system's trajectories, and a Brain-Computer Interface (BCI) unit, for the control of the robot Cartesian stiffness, which determines the interaction forces between the robot and environment. The latter control is achieved by estimating in real-time a unidimensional index from user's electroencephalographic (EEG) signals, which provides the probability of a neutral or active state. This estimated state is then translated into a stiffness value for the robotic arm, allowing a reliable modulation of the robot's impedance. A preliminary evaluation of this hybrid interface concept provided evidence on the effective execution of tasks with dynamic uncertainties, demonstrating the great potential of this control method in BMI applications for self-service and clinical care.

Induced sensorimotor brain plasticity controls pain in phantom limb patients

PubMed Central

Yanagisawa, Takufumi; Fukuma, Ryohei; Seymour, Ben; Hosomi, Koichi; Kishima, Haruhiko; Shimizu, Takeshi; Yokoi, Hiroshi; Hirata, Masayuki; Yoshimine, Toshiki; Kamitani, Yukiyasu; Saitoh, Youichi

2016-01-01

The cause of pain in a phantom limb after partial or complete deafferentation is an important problem. A popular but increasingly controversial theory is that it results from maladaptive reorganization of the sensorimotor cortex, suggesting that experimental induction of further reorganization should affect the pain, especially if it results in functional restoration. Here we use a brain–machine interface (BMI) based on real-time magnetoencephalography signals to reconstruct affected hand movements with a robotic hand. BMI training induces significant plasticity in the sensorimotor cortex, manifested as improved discriminability of movement information and enhanced prosthetic control. Contrary to our expectation that functional restoration would reduce pain, the BMI training with the phantom hand intensifies the pain. In contrast, BMI training designed to dissociate the prosthetic and phantom hands actually reduces pain. These results reveal a functional relevance between sensorimotor cortical plasticity and pain, and may provide a novel treatment with BMI neurofeedback. PMID:27807349

EXiO-A Brain-Controlled Lower Limb Exoskeleton for Rhesus Macaques.

PubMed

Vouga, Tristan; Zhuang, Katie Z; Olivier, Jeremy; Lebedev, Mikhail A; Nicolelis, Miguel A L; Bouri, Mohamed; Bleuler, Hannes

2017-02-01

Recent advances in the field of brain-machine interfaces (BMIs) have demonstrated enormous potential to shape the future of rehabilitation and prosthetic devices. Here, a lower-limb exoskeleton controlled by the intracortical activity of an awake behaving rhesus macaque is presented as a proof-of-concept for a locomotorBMI. A detailed description of the mechanical device, including its innovative features and first experimental results, is provided. During operation, BMI-decoded position and velocity are directly mapped onto the bipedal exoskeleton's motions, which then move the monkey's legs as the monkey remains physicallypassive. To meet the unique requirements of such an application, the exoskeleton's features include: high output torque with backdrivable actuation, size adjustability, and safe user-robot interface. In addition, a novel rope transmission is introduced and implemented. To test the performance of the exoskeleton, a mechanical assessment was conducted, which yielded quantifiable results for transparency, efficiency, stiffness, and tracking performance. Usage under both brain control and automated actuation demonstrates the device's capability to fulfill the demanding needs of this application. These results lay the groundwork for further advancement in BMI-controlled devices for primates including humans.

ICM: a web server for integrated clustering of multi-dimensional biomedical data.

PubMed

He, Song; He, Haochen; Xu, Wenjian; Huang, Xin; Jiang, Shuai; Li, Fei; He, Fuchu; Bo, Xiaochen

2016-07-08

Large-scale efforts for parallel acquisition of multi-omics profiling continue to generate extensive amounts of multi-dimensional biomedical data. Thus, integrated clustering of multiple types of omics data is essential for developing individual-based treatments and precision medicine. However, while rapid progress has been made, methods for integrated clustering are lacking an intuitive web interface that facilitates the biomedical researchers without sufficient programming skills. Here, we present a web tool, named Integrated Clustering of Multi-dimensional biomedical data (ICM), that provides an interface from which to fuse, cluster and visualize multi-dimensional biomedical data and knowledge. With ICM, users can explore the heterogeneity of a disease or a biological process by identifying subgroups of patients. The results obtained can then be interactively modified by using an intuitive user interface. Researchers can also exchange the results from ICM with collaborators via a web link containing a Project ID number that will directly pull up the analysis results being shared. ICM also support incremental clustering that allows users to add new sample data into the data of a previous study to obtain a clustering result. Currently, the ICM web server is available with no login requirement and at no cost at http://biotech.bmi.ac.cn/icm/. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Brain-machine interfacing control of whole-body humanoid motion

PubMed Central

Bouyarmane, Karim; Vaillant, Joris; Sugimoto, Norikazu; Keith, François; Furukawa, Jun-ichiro; Morimoto, Jun

2014-01-01

We propose to tackle in this paper the problem of controlling whole-body humanoid robot behavior through non-invasive brain-machine interfacing (BMI), motivated by the perspective of mapping human motor control strategies to human-like mechanical avatar. Our solution is based on the adequate reduction of the controllable dimensionality of a high-DOF humanoid motion in line with the state-of-the-art possibilities of non-invasive BMI technologies, leaving the complement subspace part of the motion to be planned and executed by an autonomous humanoid whole-body motion planning and control framework. The results are shown in full physics-based simulation of a 36-degree-of-freedom humanoid motion controlled by a user through EEG-extracted brain signals generated with motor imagery task. PMID:25140134

Brain-machine interfaces can accelerate clarification of the principal mysteries and real plasticity of the brain

PubMed Central

Sakurai, Yoshio

2014-01-01

This perspective emphasizes that the brain-machine interface (BMI) research has the potential to clarify major mysteries of the brain and that such clarification of the mysteries by neuroscience is needed to develop BMIs. I enumerate five principal mysteries. The first is “how is information encoded in the brain?” This is the fundamental question for understanding what our minds are and is related to the verification of Hebb’s cell assembly theory. The second is “how is information distributed in the brain?” This is also a reconsideration of the functional localization of the brain. The third is “what is the function of the ongoing activity of the brain?” This is the problem of how the brain is active during no-task periods and what meaning such spontaneous activity has. The fourth is “how does the bodily behavior affect the brain function?” This is the problem of brain-body interaction, and obtaining a new “body” by a BMI leads to a possibility of changes in the owner’s brain. The last is “to what extent can the brain induce plasticity?” Most BMIs require changes in the brain’s neuronal activity to realize higher performance, and the neuronal operant conditioning inherent in the BMIs further enhances changes in the activity. PMID:24904323

Bioinformatics and Medical Informatics: Collaborations on the Road to Genomic Medicine?

PubMed Central

Maojo, Victor; Kulikowski, Casimir A.

2003-01-01

In this report, the authors compare and contrast medical informatics (MI) and bioinformatics (BI) and provide a viewpoint on their complementarities and potential for collaboration in various subfields. The authors compare MI and BI along several dimensions, including: (1) historical development of the disciplines, (2) their scientific foundations, (3) data quality and analysis, (4) integration of knowledge and databases, (5) informatics tools to support practice, (6) informatics methods to support research (signal processing, imaging and vision, and computational modeling, (7) professional and patient continuing education, and (8) education and training. It is pointed out that, while the two disciplines differ in their histories, scientific foundations, and methodologic approaches to research in various areas, they nevertheless share methods and tools, which provides a basis for exchange of experience in their different applications. MI expertise in developing health care applications and the strength of BI in biological “discovery science” complement each other well. The new field of biomedical informatics (BMI) holds great promise for developing informatics methods that will be crucial in the development of genomic medicine. The future of BMI will be influenced strongly by whether significant advances in clinical practice and biomedical research come about from separate efforts in MI and BI, or from emerging, hybrid informatics subdisciplines at their interface. PMID:12925552

Using Reinforcement Learning to Provide Stable Brain-Machine Interface Control Despite Neural Input Reorganization

PubMed Central

Pohlmeyer, Eric A.; Mahmoudi, Babak; Geng, Shijia; Prins, Noeline W.; Sanchez, Justin C.

2014-01-01

Brain-machine interface (BMI) systems give users direct neural control of robotic, communication, or functional electrical stimulation systems. As BMI systems begin transitioning from laboratory settings into activities of daily living, an important goal is to develop neural decoding algorithms that can be calibrated with a minimal burden on the user, provide stable control for long periods of time, and can be responsive to fluctuations in the decoder’s neural input space (e.g. neurons appearing or being lost amongst electrode recordings). These are significant challenges for static neural decoding algorithms that assume stationary input/output relationships. Here we use an actor-critic reinforcement learning architecture to provide an adaptive BMI controller that can successfully adapt to dramatic neural reorganizations, can maintain its performance over long time periods, and which does not require the user to produce specific kinetic or kinematic activities to calibrate the BMI. Two marmoset monkeys used the Reinforcement Learning BMI (RLBMI) to successfully control a robotic arm during a two-target reaching task. The RLBMI was initialized using random initial conditions, and it quickly learned to control the robot from brain states using only a binary evaluative feedback regarding whether previously chosen robot actions were good or bad. The RLBMI was able to maintain control over the system throughout sessions spanning multiple weeks. Furthermore, the RLBMI was able to quickly adapt and maintain control of the robot despite dramatic perturbations to the neural inputs, including a series of tests in which the neuron input space was deliberately halved or doubled. PMID:24498055

Changes in neuromuscular activity during motor training with a body-machine interface after spinal cord injury.

PubMed

Pierella, C; De Luca, A; Tasso, E; Cervetto, F; Gamba, S; Losio, L; Quinland, E; Venegoni, A; Mandraccia, S; Muller, I; Massone, A; Mussa-Ivaldi, F A; Casadio, M

2017-07-01

Body machine interfaces (BMIs) are used by people with severe motor disabilities to control external devices, but they also offer the opportunity to focus on rehabilitative goals. In this study we introduced in a clinical setting a BMI that was integrated by the therapists in the rehabilitative treatments of 2 spinal cord injured (SCI) subjects for 5 weeks. The BMI mapped the user's residual upper body mobility onto the two coordinates of a cursor on a screen. By controlling the cursor, the user engaged in playing computer games. The BMI allowed the mapping between body and cursor spaces to be modified, gradually challenging the user to exercise more impaired movements. With this approach, we were able to change our subjects' behavior, who initially used almost exclusively their proximal upper body-shoulders and arms - for using the BMI. By the end of training, cursor control was shifted toward more distal body regions - forearms instead of upper arms - with an increase of mobility and strength of all the degrees of freedom involved in the control. The clinical tests and the electromyographic signals from the main muscles of the upper body confirmed the positive effect of the training. Encouraging the subjects to explore different and sometimes unusual movement combinations was beneficial for recovering distal arm functions and for increasing their overall mobility.

Rapid control and feedback rates enhance neuroprosthetic control

PubMed Central

Shanechi, Maryam M.; Orsborn, Amy L.; Moorman, Helene G.; Gowda, Suraj; Dangi, Siddharth; Carmena, Jose M.

2017-01-01

Brain-machine interfaces (BMI) create novel sensorimotor pathways for action. Much as the sensorimotor apparatus shapes natural motor control, the BMI pathway characteristics may also influence neuroprosthetic control. Here, we explore the influence of control and feedback rates, where control rate indicates how often motor commands are sent from the brain to the prosthetic, and feedback rate indicates how often visual feedback of the prosthetic is provided to the subject. We developed a new BMI that allows arbitrarily fast control and feedback rates, and used it to dissociate the effects of each rate in two monkeys. Increasing the control rate significantly improved control even when feedback rate was unchanged. Increasing the feedback rate further facilitated control. We also show that our high-rate BMI significantly outperformed state-of-the-art methods due to higher control and feedback rates, combined with a different point process mathematical encoding model. Our BMI paradigm can dissect the contribution of different elements in the sensorimotor pathway, providing a unique tool for studying neuroprosthetic control mechanisms. PMID:28059065

Rapid control and feedback rates enhance neuroprosthetic control

NASA Astrophysics Data System (ADS)

Shanechi, Maryam M.; Orsborn, Amy L.; Moorman, Helene G.; Gowda, Suraj; Dangi, Siddharth; Carmena, Jose M.

2017-01-01

Brain-machine interfaces (BMI) create novel sensorimotor pathways for action. Much as the sensorimotor apparatus shapes natural motor control, the BMI pathway characteristics may also influence neuroprosthetic control. Here, we explore the influence of control and feedback rates, where control rate indicates how often motor commands are sent from the brain to the prosthetic, and feedback rate indicates how often visual feedback of the prosthetic is provided to the subject. We developed a new BMI that allows arbitrarily fast control and feedback rates, and used it to dissociate the effects of each rate in two monkeys. Increasing the control rate significantly improved control even when feedback rate was unchanged. Increasing the feedback rate further facilitated control. We also show that our high-rate BMI significantly outperformed state-of-the-art methods due to higher control and feedback rates, combined with a different point process mathematical encoding model. Our BMI paradigm can dissect the contribution of different elements in the sensorimotor pathway, providing a unique tool for studying neuroprosthetic control mechanisms.

Design of a Closed-Loop, Bidirectional Brain Machine Interface System With Energy Efficient Neural Feature Extraction and PID Control.

PubMed

Liu, Xilin; Zhang, Milin; Richardson, Andrew G; Lucas, Timothy H; Van der Spiegel, Jan

2017-08-01

This paper presents a bidirectional brain machine interface (BMI) microsystem designed for closed-loop neuroscience research, especially experiments in freely behaving animals. The system-on-chip (SoC) consists of 16-channel neural recording front-ends, neural feature extraction units, 16-channel programmable neural stimulator back-ends, in-channel programmable closed-loop controllers, global analog-digital converters (ADC), and peripheral circuits. The proposed neural feature extraction units includes 1) an ultra low-power neural energy extraction unit enabling a 64-step natural logarithmic domain frequency tuning, and 2) a current-mode action potential (AP) detection unit with time-amplitude window discriminator. A programmable proportional-integral-derivative (PID) controller has been integrated in each channel enabling a various of closed-loop operations. The implemented ADCs include a 10-bit voltage-mode successive approximation register (SAR) ADC for the digitization of the neural feature outputs and/or local field potential (LFP) outputs, and an 8-bit current-mode SAR ADC for the digitization of the action potential outputs. The multi-mode stimulator can be programmed to perform monopolar or bipolar, symmetrical or asymmetrical charge balanced stimulation with a maximum current of 4 mA in an arbitrary channel configuration. The chip has been fabricated in 0.18 μ m CMOS technology, occupying a silicon area of 3.7 mm 2 . The chip dissipates 56 μW/ch on average. General purpose low-power microcontroller with Bluetooth module are integrated in the system to provide wireless link and SoC configuration. Methods, circuit techniques and system topology proposed in this work can be used in a wide range of relevant neurophysiology research, especially closed-loop BMI experiments.

Highly efficient lithium composite anode with hydrophobic molten salt in seawater

NASA Astrophysics Data System (ADS)

Zhang, Yancheng; Urquidi-Macdonald, Mirna

A lithium composite anode (lithium/1-butyl-3-methyl-imidazoleum hexafluorophosphate (BMI +PF 6-)/4-VLZ) for primary lithium/seawater semi-fuel-cells is proposed to reduce lithium-water parasitic reaction and, hence, increase the lithium anodic efficiency up to 100%. The lithium composite anode was activated when in contact with artificial seawater (3% NaCl solution) and the output was a stable anodic current density at 0.2 mA/cm 2, which lasted about 10 h under potentiostatic polarization at +0.5 V versus open circuit potential (OCP); the anodic efficiency was indirectly measured to be 100%. With time, a small traces of water diffused through the hydrophobic molten salt, BMI +PF 6-, reached the lithium interface and formed a double layer film (LiH/LiOH). Accordingly, the current density decreased and the anodic efficiency was estimated to be 90%. The hypothesis of small traces of water penetrating the molten salt and reaching the lithium anode—after several hours of operation—is supported by the collected experimental current density and hydrogen evolution, electrochemical impedance spectrum analysis, and non-mechanistic interface film modeling of lithium/BMI +PF 6-.

A four-dimensional virtual hand brain-machine interface using active dimension selection.

PubMed

Rouse, Adam G

2016-06-01

Brain-machine interfaces (BMI) traditionally rely on a fixed, linear transformation from neural signals to an output state-space. In this study, the assumption that a BMI must control a fixed, orthogonal basis set was challenged and a novel active dimension selection (ADS) decoder was explored. ADS utilizes a two stage decoder by using neural signals to both (i) select an active dimension being controlled and (ii) control the velocity along the selected dimension. ADS decoding was tested in a monkey using 16 single units from premotor and primary motor cortex to successfully control a virtual hand avatar to move to eight different postures. Following training with the ADS decoder to control 2, 3, and then 4 dimensions, each emulating a grasp shape of the hand, performance reached 93% correct with a bit rate of 2.4 bits s(-1) for eight targets. Selection of eight targets using ADS control was more efficient, as measured by bit rate, than either full four-dimensional control or computer assisted one-dimensional control. ADS decoding allows a user to quickly and efficiently select different hand postures. This novel decoding scheme represents a potential method to reduce the complexity of high-dimension BMI control of the hand.

An online brain-machine interface using decoding of movement direction from the human electrocorticogram

NASA Astrophysics Data System (ADS)

Milekovic, Tomislav; Fischer, Jörg; Pistohl, Tobias; Ruescher, Johanna; Schulze-Bonhage, Andreas; Aertsen, Ad; Rickert, Jörn; Ball, Tonio; Mehring, Carsten

2012-08-01

A brain-machine interface (BMI) can be used to control movements of an artificial effector, e.g. movements of an arm prosthesis, by motor cortical signals that control the equivalent movements of the corresponding body part, e.g. arm movements. This approach has been successfully applied in monkeys and humans by accurately extracting parameters of movements from the spiking activity of multiple single neurons. We show that the same approach can be realized using brain activity measured directly from the surface of the human cortex using electrocorticography (ECoG). Five subjects, implanted with ECoG implants for the purpose of epilepsy assessment, took part in our study. Subjects used directionally dependent ECoG signals, recorded during active movements of a single arm, to control a computer cursor in one out of two directions. Significant BMI control was achieved in four out of five subjects with correct directional decoding in 69%-86% of the trials (75% on average). Our results demonstrate the feasibility of an online BMI using decoding of movement direction from human ECoG signals. Thus, to achieve such BMIs, ECoG signals might be used in conjunction with or as an alternative to intracortical neural signals.

A Real-Time Brain-Machine Interface Combining Motor Target and Trajectory Intent Using an Optimal Feedback Control Design

PubMed Central

Shanechi, Maryam M.; Williams, Ziv M.; Wornell, Gregory W.; Hu, Rollin C.; Powers, Marissa; Brown, Emery N.

2013-01-01

Real-time brain-machine interfaces (BMI) have focused on either estimating the continuous movement trajectory or target intent. However, natural movement often incorporates both. Additionally, BMIs can be modeled as a feedback control system in which the subject modulates the neural activity to move the prosthetic device towards a desired target while receiving real-time sensory feedback of the state of the movement. We develop a novel real-time BMI using an optimal feedback control design that jointly estimates the movement target and trajectory of monkeys in two stages. First, the target is decoded from neural spiking activity before movement initiation. Second, the trajectory is decoded by combining the decoded target with the peri-movement spiking activity using an optimal feedback control design. This design exploits a recursive Bayesian decoder that uses an optimal feedback control model of the sensorimotor system to take into account the intended target location and the sensory feedback in its trajectory estimation from spiking activity. The real-time BMI processes the spiking activity directly using point process modeling. We implement the BMI in experiments consisting of an instructed-delay center-out task in which monkeys are presented with a target location on the screen during a delay period and then have to move a cursor to it without touching the incorrect targets. We show that the two-stage BMI performs more accurately than either stage alone. Correct target prediction can compensate for inaccurate trajectory estimation and vice versa. The optimal feedback control design also results in trajectories that are smoother and have lower estimation error. The two-stage decoder also performs better than linear regression approaches in offline cross-validation analyses. Our results demonstrate the advantage of a BMI design that jointly estimates the target and trajectory of movement and more closely mimics the sensorimotor control system. PMID:23593130

PyMT: A Python package for model-coupling in the Earth sciences

NASA Astrophysics Data System (ADS)

Hutton, E.

2016-12-01

The current landscape of Earth-system models is not only broad in scientific scope, but also broad in type. On the one hand, the large variety of models is exciting, as it provides fertile ground for extending or linking models together in novel ways to answer new scientific questions. However, the heterogeneity in model type acts to inhibit model coupling, model development, or even model use. Existing models are written in a variety of programming languages, operate on different grids, use their own file formats (both for input and output), have different user interfaces, have their own time steps, etc. Each of these factors become obstructions to scientists wanting to couple, extend - or simply run - existing models. For scientists whose main focus may not be computer science these barriers become even larger and become significant logistical hurdles. And this is all before the scientific difficulties of coupling or running models are addressed. The CSDMS Python Modeling Toolkit (PyMT) was developed to help non-computer scientists deal with these sorts of modeling logistics. PyMT is the fundamental package the Community Surface Dynamics Modeling System uses for the coupling of models that expose the Basic Modeling Interface (BMI). It contains: Tools necessary for coupling models of disparate time and space scales (including grid mappers) Time-steppers that coordinate the sequencing of coupled models Exchange of data between BMI-enabled models Wrappers that automatically load BMI-enabled models into the PyMT framework Utilities that support open-source interfaces (UGRID, SGRID,CSDMS Standard Names, etc.) A collection of community-submitted models, written in a variety of programminglanguages, from a variety of process domains - but all usable from within the Python programming language A plug-in framework for adding additional BMI-enabled models to the framework In this presentation we intoduce the basics of the PyMT as well as provide an example of coupling models of different domains and grid types.

A brain-machine interface enables bimanual arm movements in monkeys.

PubMed

Ifft, Peter J; Shokur, Solaiman; Li, Zheng; Lebedev, Mikhail A; Nicolelis, Miguel A L

2013-11-06

Brain-machine interfaces (BMIs) are artificial systems that aim to restore sensation and movement to paralyzed patients. So far, BMIs have enabled only one arm to be moved at a time. Control of bimanual arm movements remains a major challenge. We have developed and tested a bimanual BMI that enables rhesus monkeys to control two avatar arms simultaneously. The bimanual BMI was based on the extracellular activity of 374 to 497 neurons recorded from several frontal and parietal cortical areas of both cerebral hemispheres. Cortical activity was transformed into movements of the two arms with a decoding algorithm called a fifth-order unscented Kalman filter (UKF). The UKF was trained either during a manual task performed with two joysticks or by having the monkeys passively observe the movements of avatar arms. Most cortical neurons changed their modulation patterns when both arms were engaged simultaneously. Representing the two arms jointly in a single UKF decoder resulted in improved decoding performance compared with using separate decoders for each arm. As the animals' performance in bimanual BMI control improved over time, we observed widespread plasticity in frontal and parietal cortical areas. Neuronal representation of the avatar and reach targets was enhanced with learning, whereas pairwise correlations between neurons initially increased and then decreased. These results suggest that cortical networks may assimilate the two avatar arms through BMI control. These findings should help in the design of more sophisticated BMIs capable of enabling bimanual motor control in human patients.

Brain-machine interface control of a manipulator using small-world neural network and shared control strategy.

PubMed

Li, Ting; Hong, Jun; Zhang, Jinhua; Guo, Feng

2014-03-15

The improvement of the resolution of brain signal and the ability to control external device has been the most important goal in BMI research field. This paper describes a non-invasive brain-actuated manipulator experiment, which defined a paradigm for the motion control of a serial manipulator based on motor imagery and shared control. The techniques of component selection, spatial filtering and classification of motor imagery were involved. Small-world neural network (SWNN) was used to classify five brain states. To verify the effectiveness of the proposed classifier, we replace the SWNN classifier by a radial basis function (RBF) networks neural network, a standard multi-layered feed-forward backpropagation network (SMN) and a multi-SVM classifier, with the same features for the classification. The results also indicate that the proposed classifier achieves a 3.83% improvement over the best results of other classifiers. We proposed a shared control method consisting of two control patterns to expand the control of BMI from the software angle. The job of path building for reaching the 'end' point was designated as an assessment task. We recorded all paths contributed by subjects and picked up relevant parameters as evaluation coefficients. With the assistance of two control patterns and series of machine learning algorithms, the proposed BMI originally achieved the motion control of a manipulator in the whole workspace. According to experimental results, we confirmed the feasibility of the proposed BMI method for 3D motion control of a manipulator using EEG during motor imagery. Copyright © 2013 Elsevier B.V. All rights reserved.

Optimal feedback control successfully explains changes in neural modulations during experiments with brain-machine interfaces.

PubMed

Benyamini, Miri; Zacksenhouse, Miriam

2015-01-01

Recent experiments with brain-machine-interfaces (BMIs) indicate that the extent of neural modulations increased abruptly upon starting to operate the interface, and especially after the monkey stopped moving its hand. In contrast, neural modulations that are correlated with the kinematics of the movement remained relatively unchanged. Here we demonstrate that similar changes are produced by simulated neurons that encode the relevant signals generated by an optimal feedback controller during simulated BMI experiments. The optimal feedback controller relies on state estimation that integrates both visual and proprioceptive feedback with prior estimations from an internal model. The processing required for optimal state estimation and control were conducted in the state-space, and neural recording was simulated by modeling two populations of neurons that encode either only the estimated state or also the control signal. Spike counts were generated as realizations of doubly stochastic Poisson processes with linear tuning curves. The model successfully reconstructs the main features of the kinematics and neural activity during regular reaching movements. Most importantly, the activity of the simulated neurons successfully reproduces the observed changes in neural modulations upon switching to brain control. Further theoretical analysis and simulations indicate that increasing the process noise during normal reaching movement results in similar changes in neural modulations. Thus, we conclude that the observed changes in neural modulations during BMI experiments can be attributed to increasing process noise associated with the imperfect BMI filter, and, more directly, to the resulting increase in the variance of the encoded signals associated with state estimation and the required control signal.

Optimal feedback control successfully explains changes in neural modulations during experiments with brain-machine interfaces

PubMed Central

Benyamini, Miri; Zacksenhouse, Miriam

2015-01-01

Recent experiments with brain-machine-interfaces (BMIs) indicate that the extent of neural modulations increased abruptly upon starting to operate the interface, and especially after the monkey stopped moving its hand. In contrast, neural modulations that are correlated with the kinematics of the movement remained relatively unchanged. Here we demonstrate that similar changes are produced by simulated neurons that encode the relevant signals generated by an optimal feedback controller during simulated BMI experiments. The optimal feedback controller relies on state estimation that integrates both visual and proprioceptive feedback with prior estimations from an internal model. The processing required for optimal state estimation and control were conducted in the state-space, and neural recording was simulated by modeling two populations of neurons that encode either only the estimated state or also the control signal. Spike counts were generated as realizations of doubly stochastic Poisson processes with linear tuning curves. The model successfully reconstructs the main features of the kinematics and neural activity during regular reaching movements. Most importantly, the activity of the simulated neurons successfully reproduces the observed changes in neural modulations upon switching to brain control. Further theoretical analysis and simulations indicate that increasing the process noise during normal reaching movement results in similar changes in neural modulations. Thus, we conclude that the observed changes in neural modulations during BMI experiments can be attributed to increasing process noise associated with the imperfect BMI filter, and, more directly, to the resulting increase in the variance of the encoded signals associated with state estimation and the required control signal. PMID:26042002

Relationships Between Illicit Drug Use and Body Mass Index Among Adolescents.

PubMed

Blackstone, Sarah R; Herrmann, Lynn K

2016-02-01

Prior research has established associations between body mass index (BMI) and use of alcohol, tobacco, and marijuana. However, little research has been done investigating the relationship between other common illicit drugs and BMI trends. The present study investigated whether adolescents who reported using illicit drugs showed differences in BMI compared to peers who reported no drug use. There was a positive relationship between drug use and BMI as well as the number of drugs used and BMI. The results suggested that the positive relationship between the use of illicit drugs and BMI is largely due to smoking. Further research needs to ascertain whether smoking, illicit drug use, or both are among the first of many unhealthy behaviors that can subsequently lead to greater gains in BMI. Implications for health educators are discussed. © 2015 Society for Public Health Education.

Simultaneous scalp electroencephalography (EEG), electromyography (EMG), and whole-body segmental inertial recording for multi-modal neural decoding.

PubMed

Bulea, Thomas C; Kilicarslan, Atilla; Ozdemir, Recep; Paloski, William H; Contreras-Vidal, Jose L

2013-07-26

Recent studies support the involvement of supraspinal networks in control of bipedal human walking. Part of this evidence encompasses studies, including our previous work, demonstrating that gait kinematics and limb coordination during treadmill walking can be inferred from the scalp electroencephalogram (EEG) with reasonably high decoding accuracies. These results provide impetus for development of non-invasive brain-machine-interface (BMI) systems for use in restoration and/or augmentation of gait- a primary goal of rehabilitation research. To date, studies examining EEG decoding of activity during gait have been limited to treadmill walking in a controlled environment. However, to be practically viable a BMI system must be applicable for use in everyday locomotor tasks such as over ground walking and turning. Here, we present a novel protocol for non-invasive collection of brain activity (EEG), muscle activity (electromyography (EMG)), and whole-body kinematic data (head, torso, and limb trajectories) during both treadmill and over ground walking tasks. By collecting these data in the uncontrolled environment insight can be gained regarding the feasibility of decoding unconstrained gait and surface EMG from scalp EEG.

Who Needs to Fit In? Who Gets to Stand Out? Communication Technologies Including Brain-Machine Interfaces Revealed from the Perspectives of Special Education School Teachers through an Ableism Lens

ERIC Educational Resources Information Center

Diep, Lucy; Wolbring, Gregor

2013-01-01

Some new and envisioned technologies such as brain machine interfaces (BMI) that are being developed initially for people with disabilities, but whose use can also be expanded to the general public have the potential to change body ability expectations of disabled and non-disabled people beyond the species-typical. The ways in which this dynamic…

Errare machinale est: the use of error-related potentials in brain-machine interfaces

PubMed Central

Chavarriaga, Ricardo; Sobolewski, Aleksander; Millán, José del R.

2014-01-01

The ability to recognize errors is crucial for efficient behavior. Numerous studies have identified electrophysiological correlates of error recognition in the human brain (error-related potentials, ErrPs). Consequently, it has been proposed to use these signals to improve human-computer interaction (HCI) or brain-machine interfacing (BMI). Here, we present a review of over a decade of developments toward this goal. This body of work provides consistent evidence that ErrPs can be successfully detected on a single-trial basis, and that they can be effectively used in both HCI and BMI applications. We first describe the ErrP phenomenon and follow up with an analysis of different strategies to increase the robustness of a system by incorporating single-trial ErrP recognition, either by correcting the machine's actions or by providing means for its error-based adaptation. These approaches can be applied both when the user employs traditional HCI input devices or in combination with another BMI channel. Finally, we discuss the current challenges that have to be overcome in order to fully integrate ErrPs into practical applications. This includes, in particular, the characterization of such signals during real(istic) applications, as well as the possibility of extracting richer information from them, going beyond the time-locked decoding that dominates current approaches. PMID:25100937

A four-dimensional virtual hand brain-machine interface using active dimension selection

NASA Astrophysics Data System (ADS)

Rouse, Adam G.

2016-06-01

Objective. Brain-machine interfaces (BMI) traditionally rely on a fixed, linear transformation from neural signals to an output state-space. In this study, the assumption that a BMI must control a fixed, orthogonal basis set was challenged and a novel active dimension selection (ADS) decoder was explored. Approach. ADS utilizes a two stage decoder by using neural signals to both (i) select an active dimension being controlled and (ii) control the velocity along the selected dimension. ADS decoding was tested in a monkey using 16 single units from premotor and primary motor cortex to successfully control a virtual hand avatar to move to eight different postures. Main results. Following training with the ADS decoder to control 2, 3, and then 4 dimensions, each emulating a grasp shape of the hand, performance reached 93% correct with a bit rate of 2.4 bits s-1 for eight targets. Selection of eight targets using ADS control was more efficient, as measured by bit rate, than either full four-dimensional control or computer assisted one-dimensional control. Significance. ADS decoding allows a user to quickly and efficiently select different hand postures. This novel decoding scheme represents a potential method to reduce the complexity of high-dimension BMI control of the hand.

A four-dimensional virtual hand brain-machine interface using active dimension selection

PubMed Central

Rouse, Adam G.

2018-01-01

Objective Brain-machine interfaces (BMI) traditionally rely on a fixed, linear transformation from neural signals to an output state-space. In this study, the assumption that a BMI must control a fixed, orthogonal basis set was challenged and a novel active dimension selection (ADS) decoder was explored. Approach ADS utilizes a two stage decoder by using neural signals to both i) select an active dimension being controlled and ii) control the velocity along the selected dimension. ADS decoding was tested in a monkey using 16 single units from premotor and primary motor cortex to successfully control a virtual hand avatar to move to eight different postures. Main Results Following training with the ADS decoder to control 2, 3, and then 4 dimensions, each emulating a grasp shape of the hand, performance reached 93% correct with a bit rate of 2.4 bits/s for eight targets. Selection of eight targets using ADS control was more efficient, as measured by bit rate, than either full four-dimensional control or computer assisted one-dimensional control. Significance ADS decoding allows a user to quickly and efficiently select different hand postures. This novel decoding scheme represents a potential method to reduce the complexity of high-dimension BMI control of the hand. PMID:27171896

Long-Term Training with a Brain-Machine Interface-Based Gait Protocol Induces Partial Neurological Recovery in Paraplegic Patients.

PubMed

Donati, Ana R C; Shokur, Solaiman; Morya, Edgard; Campos, Debora S F; Moioli, Renan C; Gitti, Claudia M; Augusto, Patricia B; Tripodi, Sandra; Pires, Cristhiane G; Pereira, Gislaine A; Brasil, Fabricio L; Gallo, Simone; Lin, Anthony A; Takigami, Angelo K; Aratanha, Maria A; Joshi, Sanjay; Bleuler, Hannes; Cheng, Gordon; Rudolph, Alan; Nicolelis, Miguel A L

2016-08-11

Brain-machine interfaces (BMIs) provide a new assistive strategy aimed at restoring mobility in severely paralyzed patients. Yet, no study in animals or in human subjects has indicated that long-term BMI training could induce any type of clinical recovery. Eight chronic (3-13 years) spinal cord injury (SCI) paraplegics were subjected to long-term training (12 months) with a multi-stage BMI-based gait neurorehabilitation paradigm aimed at restoring locomotion. This paradigm combined intense immersive virtual reality training, enriched visual-tactile feedback, and walking with two EEG-controlled robotic actuators, including a custom-designed lower limb exoskeleton capable of delivering tactile feedback to subjects. Following 12 months of training with this paradigm, all eight patients experienced neurological improvements in somatic sensation (pain localization, fine/crude touch, and proprioceptive sensing) in multiple dermatomes. Patients also regained voluntary motor control in key muscles below the SCI level, as measured by EMGs, resulting in marked improvement in their walking index. As a result, 50% of these patients were upgraded to an incomplete paraplegia classification. Neurological recovery was paralleled by the reemergence of lower limb motor imagery at cortical level. We hypothesize that this unprecedented neurological recovery results from both cortical and spinal cord plasticity triggered by long-term BMI usage.

Long-Term Training with a Brain-Machine Interface-Based Gait Protocol Induces Partial Neurological Recovery in Paraplegic Patients

PubMed Central

Donati, Ana R. C.; Shokur, Solaiman; Morya, Edgard; Campos, Debora S. F.; Moioli, Renan C.; Gitti, Claudia M.; Augusto, Patricia B.; Tripodi, Sandra; Pires, Cristhiane G.; Pereira, Gislaine A.; Brasil, Fabricio L.; Gallo, Simone; Lin, Anthony A.; Takigami, Angelo K.; Aratanha, Maria A.; Joshi, Sanjay; Bleuler, Hannes; Cheng, Gordon; Rudolph, Alan; Nicolelis, Miguel A. L.

2016-01-01

Brain-machine interfaces (BMIs) provide a new assistive strategy aimed at restoring mobility in severely paralyzed patients. Yet, no study in animals or in human subjects has indicated that long-term BMI training could induce any type of clinical recovery. Eight chronic (3–13 years) spinal cord injury (SCI) paraplegics were subjected to long-term training (12 months) with a multi-stage BMI-based gait neurorehabilitation paradigm aimed at restoring locomotion. This paradigm combined intense immersive virtual reality training, enriched visual-tactile feedback, and walking with two EEG-controlled robotic actuators, including a custom-designed lower limb exoskeleton capable of delivering tactile feedback to subjects. Following 12 months of training with this paradigm, all eight patients experienced neurological improvements in somatic sensation (pain localization, fine/crude touch, and proprioceptive sensing) in multiple dermatomes. Patients also regained voluntary motor control in key muscles below the SCI level, as measured by EMGs, resulting in marked improvement in their walking index. As a result, 50% of these patients were upgraded to an incomplete paraplegia classification. Neurological recovery was paralleled by the reemergence of lower limb motor imagery at cortical level. We hypothesize that this unprecedented neurological recovery results from both cortical and spinal cord plasticity triggered by long-term BMI usage. PMID:27513629

Multiscale decoding for reliable brain-machine interface performance over time.

PubMed

Han-Lin Hsieh; Wong, Yan T; Pesaran, Bijan; Shanechi, Maryam M

2017-07-01

Recordings from invasive implants can degrade over time, resulting in a loss of spiking activity for some electrodes. For brain-machine interfaces (BMI), such a signal degradation lowers control performance. Achieving reliable performance over time is critical for BMI clinical viability. One approach to improve BMI longevity is to simultaneously use spikes and other recording modalities such as local field potentials (LFP), which are more robust to signal degradation over time. We have developed a multiscale decoder that can simultaneously model the different statistical profiles of multi-scale spike/LFP activity (discrete spikes vs. continuous LFP). This decoder can also run at multiple time-scales (millisecond for spikes vs. tens of milliseconds for LFP). Here, we validate the multiscale decoder for estimating the movement of 7 major upper-arm joint angles in a non-human primate (NHP) during a 3D reach-to-grasp task. The multiscale decoder uses motor cortical spike/LFP recordings as its input. We show that the multiscale decoder can improve decoding accuracy by adding information from LFP to spikes, while running at the fast millisecond time-scale of the spiking activity. Moreover, this improvement is achieved using relatively few LFP channels, demonstrating the robustness of the approach. These results suggest that using multiscale decoders has the potential to improve the reliability and longevity of BMIs.

A Brain-Machine Interface Based on ERD/ERS for an Upper-Limb Exoskeleton Control.

PubMed

Tang, Zhichuan; Sun, Shouqian; Zhang, Sanyuan; Chen, Yumiao; Li, Chao; Chen, Shi

2016-12-02

To recognize the user's motion intention, brain-machine interfaces (BMI) usually decode movements from cortical activity to control exoskeletons and neuroprostheses for daily activities. The aim of this paper is to investigate whether self-induced variations of the electroencephalogram (EEG) can be useful as control signals for an upper-limb exoskeleton developed by us. A BMI based on event-related desynchronization/synchronization (ERD/ERS) is proposed. In the decoder-training phase, we investigate the offline classification performance of left versus right hand and left hand versus both feet by using motor execution (ME) or motor imagery (MI). The results indicate that the accuracies of ME sessions are higher than those of MI sessions, and left hand versus both feet paradigm achieves a better classification performance, which would be used in the online-control phase. In the online-control phase, the trained decoder is tested in two scenarios (wearing or without wearing the exoskeleton). The MI and ME sessions wearing the exoskeleton achieve mean classification accuracy of 84.29% ± 2.11% and 87.37% ± 3.06%, respectively. The present study demonstrates that the proposed BMI is effective to control the upper-limb exoskeleton, and provides a practical method by non-invasive EEG signal associated with human natural behavior for clinical applications.

Adaptation to a cortex controlled robot attached at the pelvis and engaged during locomotion in rats

PubMed Central

Song, Weiguo; Giszter, Simon F.

2011-01-01

Brain Machine Interfaces (BMIs) should ideally show robust adaptation of the BMI across different tasks and daily activities. Most BMIs have used over-practiced tasks. Little is known about BMIs in dynamic environments. How are mechanically body-coupled BMIs integrated into ongoing rhythmic dynamics, e.g., in locomotion? To examine this we designed a novel BMI using neural discharge in the hindlimb/trunk motor cortex in rats during locomotion to control a robot attached at the pelvis. We tested neural adaptation when rats experienced (a) control locomotion, (b) ‘simple elastic load’ (a robot load on locomotion without any BMI neural control) and (c) ‘BMI with elastic load’ (in which the robot loaded locomotion and a BMI neural control could counter this load). Rats significantly offset applied loads with the BMI while preserving more normal pelvic height compared to load alone. Adaptation occurred over about 100–200 step cycles in a trial. Firing rates increased in both the loaded conditions compared to baseline. Mean phases of cells’ discharge in the step cycle shifted significantly between BMI and the simple load condition. Over time more BMI cells became positively correlated with the external force and modulated more deeply, and neurons’ network correlations on a 100ms timescale increased. Loading alone showed none of these effects. The BMI neural changes of rate and force correlations persisted or increased over repeated trials. Our results show that rats have the capacity to use motor adaptation and motor learning to fairly rapidly engage hindlimb/trunk coupled BMIs in their locomotion. PMID:21414932

Coupling of snow and permafrost processes using the Basic Modeling Interface (BMI)

NASA Astrophysics Data System (ADS)

Wang, K.; Overeem, I.; Jafarov, E. E.; Piper, M.; Stewart, S.; Clow, G. D.; Schaefer, K. M.

2017-12-01

We developed a permafrost modeling tool based by implementing the Kudryavtsev empirical permafrost active layer depth model (the so-called "Ku" component). The model is specifically set up to have a basic model interface (BMI), which enhances the potential coupling to other earth surface processes model components. This model is accessible through the Web Modeling Tool in Community Surface Dynamics Modeling System (CSDMS). The Kudryavtsev model has been applied for entire Alaska to model permafrost distribution at high spatial resolution and model predictions have been verified by Circumpolar Active Layer Monitoring (CALM) in-situ observations. The Ku component uses monthly meteorological forcing, including air temperature, snow depth, and snow density, and predicts active layer thickness (ALT) and temperature on the top of permafrost (TTOP), which are important factors in snow-hydrological processes. BMI provides an easy approach to couple the models with each other. Here, we provide a case of coupling the Ku component to snow process components, including the Snow-Degree-Day (SDD) method and Snow-Energy-Balance (SEB) method, which are existing components in the hydrological model TOPOFLOW. The work flow is (1) get variables from meteorology component, set the values to snow process component, and advance the snow process component, (2) get variables from meteorology and snow component, provide these to the Ku component and advance, (3) get variables from snow process component, set the values to meteorology component, and advance the meteorology component. The next phase is to couple the permafrost component with fully BMI-compliant TOPOFLOW hydrological model, which could provide a useful tool to investigate the permafrost hydrological effect.

Hybrid Neuroprosthesis for the Upper Limb: Combining Brain-Controlled Neuromuscular Stimulation with a Multi-Joint Arm Exoskeleton

PubMed Central

Grimm, Florian; Walter, Armin; Spüler, Martin; Naros, Georgios; Rosenstiel, Wolfgang; Gharabaghi, Alireza

2016-01-01

Brain-machine interface-controlled (BMI) neurofeedback training aims to modulate cortical physiology and is applied during neurorehabilitation to increase the responsiveness of the brain to subsequent physiotherapy. In a parallel line of research, robotic exoskeletons are used in goal-oriented rehabilitation exercises for patients with severe motor impairment to extend their range of motion (ROM) and the intensity of training. Furthermore, neuromuscular electrical stimulation (NMES) is applied in neurologically impaired patients to restore muscle strength by closing the sensorimotor loop. In this proof-of-principle study, we explored an integrated approach for providing assistance as needed to amplify the task-related ROM and the movement-related brain modulation during rehabilitation exercises of severely impaired patients. For this purpose, we combined these three approaches (BMI, NMES, and exoskeleton) in an integrated neuroprosthesis and studied the feasibility of this device in seven severely affected chronic stroke patients who performed wrist flexion and extension exercises while receiving feedback via a virtual environment. They were assisted by a gravity-compensating, seven degree-of-freedom exoskeleton which was attached to the paretic arm. NMES was applied to the wrist extensor and flexor muscles during the exercises and was controlled by a hybrid BMI based on both sensorimotor cortical desynchronization (ERD) and electromyography (EMG) activity. The stimulation intensity was individualized for each targeted muscle and remained subthreshold, i.e., induced no overt support. The hybrid BMI controlled the stimulation significantly better than the offline analyzed ERD (p = 0.028) or EMG (p = 0.021) modality alone. Neuromuscular stimulation could be well integrated into the exoskeleton-based training and amplified both the task-related ROM (p = 0.009) and the movement-related brain modulation (p = 0.019). Combining a hybrid BMI with neuromuscular stimulation and antigravity assistance augments upper limb function and brain activity during rehabilitation exercises and may thus provide a novel restorative framework for severely affected stroke patients. PMID:27555805

Hybrid Neuroprosthesis for the Upper Limb: Combining Brain-Controlled Neuromuscular Stimulation with a Multi-Joint Arm Exoskeleton.

PubMed

Grimm, Florian; Walter, Armin; Spüler, Martin; Naros, Georgios; Rosenstiel, Wolfgang; Gharabaghi, Alireza

2016-01-01

Brain-machine interface-controlled (BMI) neurofeedback training aims to modulate cortical physiology and is applied during neurorehabilitation to increase the responsiveness of the brain to subsequent physiotherapy. In a parallel line of research, robotic exoskeletons are used in goal-oriented rehabilitation exercises for patients with severe motor impairment to extend their range of motion (ROM) and the intensity of training. Furthermore, neuromuscular electrical stimulation (NMES) is applied in neurologically impaired patients to restore muscle strength by closing the sensorimotor loop. In this proof-of-principle study, we explored an integrated approach for providing assistance as needed to amplify the task-related ROM and the movement-related brain modulation during rehabilitation exercises of severely impaired patients. For this purpose, we combined these three approaches (BMI, NMES, and exoskeleton) in an integrated neuroprosthesis and studied the feasibility of this device in seven severely affected chronic stroke patients who performed wrist flexion and extension exercises while receiving feedback via a virtual environment. They were assisted by a gravity-compensating, seven degree-of-freedom exoskeleton which was attached to the paretic arm. NMES was applied to the wrist extensor and flexor muscles during the exercises and was controlled by a hybrid BMI based on both sensorimotor cortical desynchronization (ERD) and electromyography (EMG) activity. The stimulation intensity was individualized for each targeted muscle and remained subthreshold, i.e., induced no overt support. The hybrid BMI controlled the stimulation significantly better than the offline analyzed ERD (p = 0.028) or EMG (p = 0.021) modality alone. Neuromuscular stimulation could be well integrated into the exoskeleton-based training and amplified both the task-related ROM (p = 0.009) and the movement-related brain modulation (p = 0.019). Combining a hybrid BMI with neuromuscular stimulation and antigravity assistance augments upper limb function and brain activity during rehabilitation exercises and may thus provide a novel restorative framework for severely affected stroke patients.

Internal models for interpreting neural population activity during sensorimotor control

PubMed Central

Golub, Matthew D; Yu, Byron M; Chase, Steven M

2015-01-01

To successfully guide limb movements, the brain takes in sensory information about the limb, internally tracks the state of the limb, and produces appropriate motor commands. It is widely believed that this process uses an internal model, which describes our prior beliefs about how the limb responds to motor commands. Here, we leveraged a brain-machine interface (BMI) paradigm in rhesus monkeys and novel statistical analyses of neural population activity to gain insight into moment-by-moment internal model computations. We discovered that a mismatch between subjects’ internal models and the actual BMI explains roughly 65% of movement errors, as well as long-standing deficiencies in BMI speed control. We then used the internal models to characterize how the neural population activity changes during BMI learning. More broadly, this work provides an approach for interpreting neural population activity in the context of how prior beliefs guide the transformation of sensory input to motor output. DOI: http://dx.doi.org/10.7554/eLife.10015.001 PMID:26646183

Visual Feedback Dominates the Sense of Agency for Brain-Machine Actions

PubMed Central

Evans, Nathan; Gale, Steven; Schurger, Aaron; Blanke, Olaf

2015-01-01

Recent advances in neuroscience and engineering have led to the development of technologies that permit the control of external devices through real-time decoding of brain activity (brain-machine interfaces; BMI). Though the feeling of controlling bodily movements (sense of agency; SOA) has been well studied and a number of well-defined sensorimotor and cognitive mechanisms have been put forth, very little is known about the SOA for BMI-actions. Using an on-line BMI, and verifying that our subjects achieved a reasonable level of control, we sought to describe the SOA for BMI-mediated actions. Our results demonstrate that discrepancies between decoded neural activity and its resultant real-time sensory feedback are associated with a decrease in the SOA, similar to SOA mechanisms proposed for bodily actions. However, if the feedback discrepancy serves to correct a poorly controlled BMI-action, then the SOA can be high and can increase with increasing discrepancy, demonstrating the dominance of visual feedback on the SOA. Taken together, our results suggest that bodily and BMI-actions rely on common mechanisms of sensorimotor integration for agency judgments, but that visual feedback dominates the SOA in the absence of overt bodily movements or proprioceptive feedback, however erroneous the visual feedback may be. PMID:26066840

Emergent coordination underlying learning to reach to grasp with a brain-machine interface.

PubMed

Vaidya, Mukta; Balasubramanian, Karthikeyan; Southerland, Joshua; Badreldin, Islam; Eleryan, Ahmed; Shattuck, Kelsey; Gururangan, Suchin; Slutzky, Marc; Osborne, Leslie; Fagg, Andrew; Oweiss, Karim; Hatsopoulos, Nicholas G

2018-04-01

The development of coordinated reach-to-grasp movement has been well studied in infants and children. However, the role of motor cortex during this development is unclear because it is difficult to study in humans. We took the approach of using a brain-machine interface (BMI) paradigm in rhesus macaques with prior therapeutic amputations to examine the emergence of novel, coordinated reach to grasp. Previous research has shown that after amputation, the cortical area previously involved in the control of the lost limb undergoes reorganization, but prior BMI work has largely relied on finding neurons that already encode specific movement-related information. In this study, we taught macaques to cortically control a robotic arm and hand through operant conditioning, using neurons that were not explicitly reach or grasp related. Over the course of training, stereotypical patterns emerged and stabilized in the cross-covariance between the reaching and grasping velocity profiles, between pairs of neurons involved in controlling reach and grasp, and to a comparable, but lesser, extent between other stable neurons in the network. In fact, we found evidence of this structured coordination between pairs composed of all combinations of neurons decoding reach or grasp and other stable neurons in the network. The degree of and participation in coordination was highly correlated across all pair types. Our approach provides a unique model for studying the development of novel, coordinated reach-to-grasp movement at the behavioral and cortical levels. NEW & NOTEWORTHY Given that motor cortex undergoes reorganization after amputation, our work focuses on training nonhuman primates with chronic amputations to use neurons that are not reach or grasp related to control a robotic arm to reach to grasp through the use of operant conditioning, mimicking early development. We studied the development of a novel, coordinated behavior at the behavioral and cortical level, and the neural plasticity in M1 associated with learning to use a brain-machine interface.

Residual Upper Arm Motor Function Primes Innervation of Paretic Forearm Muscles in Chronic Stroke after Brain-Machine Interface (BMI) Training

PubMed Central

Curado, Marco Rocha; Cossio, Eliana Garcia; Broetz, Doris; Agostini, Manuel; Cho, Woosang; Brasil, Fabricio Lima; Yilmaz, Oezge; Liberati, Giulia; Lepski, Guilherme

2015-01-01

Background Abnormal upper arm-forearm muscle synergies after stroke are poorly understood. We investigated whether upper arm function primes paralyzed forearm muscles in chronic stroke patients after Brain-Machine Interface (BMI)-based rehabilitation. Shaping upper arm-forearm muscle synergies may support individualized motor rehabilitation strategies. Methods Thirty-two chronic stroke patients with no active finger extensions were randomly assigned to experimental or sham groups and underwent daily BMI training followed by physiotherapy during four weeks. BMI sessions included desynchronization of ipsilesional brain activity and a robotic orthosis to move the paretic limb (experimental group, n = 16). In the sham group (n = 16) orthosis movements were random. Motor function was evaluated with electromyography (EMG) of forearm extensors, and upper arm and hand Fugl-Meyer assessment (FMA) scores. Patients performed distinct upper arm (e.g., shoulder flexion) and hand movements (finger extensions). Forearm EMG activity significantly higher during upper arm movements as compared to finger extensions was considered facilitation of forearm EMG activity. Intraclass correlation coefficient (ICC) was used to test inter-session reliability of facilitation of forearm EMG activity. Results Facilitation of forearm EMG activity ICC ranges from 0.52 to 0.83, indicating fair to high reliability before intervention in both limbs. Facilitation of forearm muscles is higher in the paretic as compared to the healthy limb (p<0.001). Upper arm FMA scores predict facilitation of forearm muscles after intervention in both groups (significant correlations ranged from R = 0.752, p = 0.002 to R = 0.779, p = 0.001), but only in the experimental group upper arm FMA scores predict changes in facilitation of forearm muscles after intervention (R = 0.709, p = 0.002; R = 0.827, p<0.001). Conclusions Residual upper arm motor function primes recruitment of paralyzed forearm muscles in chronic stroke patients and predicts changes in their recruitment after BMI training. This study suggests that changes in upper arm-forearm synergies contribute to stroke motor recovery, and provides candidacy guidelines for similar BMI-based clinical practice. PMID:26495971

Residual Upper Arm Motor Function Primes Innervation of Paretic Forearm Muscles in Chronic Stroke after Brain-Machine Interface (BMI) Training.

PubMed

Curado, Marco Rocha; Cossio, Eliana Garcia; Broetz, Doris; Agostini, Manuel; Cho, Woosang; Brasil, Fabricio Lima; Yilmaz, Oezge; Liberati, Giulia; Lepski, Guilherme; Birbaumer, Niels; Ramos-Murguialday, Ander

2015-01-01

Abnormal upper arm-forearm muscle synergies after stroke are poorly understood. We investigated whether upper arm function primes paralyzed forearm muscles in chronic stroke patients after Brain-Machine Interface (BMI)-based rehabilitation. Shaping upper arm-forearm muscle synergies may support individualized motor rehabilitation strategies. Thirty-two chronic stroke patients with no active finger extensions were randomly assigned to experimental or sham groups and underwent daily BMI training followed by physiotherapy during four weeks. BMI sessions included desynchronization of ipsilesional brain activity and a robotic orthosis to move the paretic limb (experimental group, n = 16). In the sham group (n = 16) orthosis movements were random. Motor function was evaluated with electromyography (EMG) of forearm extensors, and upper arm and hand Fugl-Meyer assessment (FMA) scores. Patients performed distinct upper arm (e.g., shoulder flexion) and hand movements (finger extensions). Forearm EMG activity significantly higher during upper arm movements as compared to finger extensions was considered facilitation of forearm EMG activity. Intraclass correlation coefficient (ICC) was used to test inter-session reliability of facilitation of forearm EMG activity. Facilitation of forearm EMG activity ICC ranges from 0.52 to 0.83, indicating fair to high reliability before intervention in both limbs. Facilitation of forearm muscles is higher in the paretic as compared to the healthy limb (p<0.001). Upper arm FMA scores predict facilitation of forearm muscles after intervention in both groups (significant correlations ranged from R = 0.752, p = 0.002 to R = 0.779, p = 0.001), but only in the experimental group upper arm FMA scores predict changes in facilitation of forearm muscles after intervention (R = 0.709, p = 0.002; R = 0.827, p<0.001). Residual upper arm motor function primes recruitment of paralyzed forearm muscles in chronic stroke patients and predicts changes in their recruitment after BMI training. This study suggests that changes in upper arm-forearm synergies contribute to stroke motor recovery, and provides candidacy guidelines for similar BMI-based clinical practice.

A brain-machine interface for control of medically-induced coma.

PubMed

Shanechi, Maryam M; Chemali, Jessica J; Liberman, Max; Solt, Ken; Brown, Emery N

2013-10-01

Medically-induced coma is a drug-induced state of profound brain inactivation and unconsciousness used to treat refractory intracranial hypertension and to manage treatment-resistant epilepsy. The state of coma is achieved by continually monitoring the patient's brain activity with an electroencephalogram (EEG) and manually titrating the anesthetic infusion rate to maintain a specified level of burst suppression, an EEG marker of profound brain inactivation in which bursts of electrical activity alternate with periods of quiescence or suppression. The medical coma is often required for several days. A more rational approach would be to implement a brain-machine interface (BMI) that monitors the EEG and adjusts the anesthetic infusion rate in real time to maintain the specified target level of burst suppression. We used a stochastic control framework to develop a BMI to control medically-induced coma in a rodent model. The BMI controlled an EEG-guided closed-loop infusion of the anesthetic propofol to maintain precisely specified dynamic target levels of burst suppression. We used as the control signal the burst suppression probability (BSP), the brain's instantaneous probability of being in the suppressed state. We characterized the EEG response to propofol using a two-dimensional linear compartment model and estimated the model parameters specific to each animal prior to initiating control. We derived a recursive Bayesian binary filter algorithm to compute the BSP from the EEG and controllers using a linear-quadratic-regulator and a model-predictive control strategy. Both controllers used the estimated BSP as feedback. The BMI accurately controlled burst suppression in individual rodents across dynamic target trajectories, and enabled prompt transitions between target levels while avoiding both undershoot and overshoot. The median performance error for the BMI was 3.6%, the median bias was -1.4% and the overall posterior probability of reliable control was 1 (95% Bayesian credibility interval of [0.87, 1.0]). A BMI can maintain reliable and accurate real-time control of medically-induced coma in a rodent model suggesting this strategy could be applied in patient care.

An integrated neuro-robotic interface for stroke rehabilitation using the NASA X1 powered lower limb exoskeleton.

PubMed

He, Yongtian; Nathan, Kevin; Venkatakrishnan, Anusha; Rovekamp, Roger; Beck, Christopher; Ozdemir, Recep; Francisco, Gerard E; Contreras-Vidal, Jose L

2014-01-01

Stroke remains a leading cause of disability, limiting independent ambulation in survivors, and consequently affecting quality of life (QOL). Recent technological advances in neural interfacing with robotic rehabilitation devices are promising in the context of gait rehabilitation. Here, the X1, NASA's powered robotic lower limb exoskeleton, is introduced as a potential diagnostic, assistive, and therapeutic tool for stroke rehabilitation. Additionally, the feasibility of decoding lower limb joint kinematics and kinetics during walking with the X1 from scalp electroencephalographic (EEG) signals--the first step towards the development of a brain-machine interface (BMI) system to the X1 exoskeleton--is demonstrated.

Robust Brain-Machine Interface Design Using Optimal Feedback Control Modeling and Adaptive Point Process Filtering

PubMed Central

Carmena, Jose M.

2016-01-01

Much progress has been made in brain-machine interfaces (BMI) using decoders such as Kalman filters and finding their parameters with closed-loop decoder adaptation (CLDA). However, current decoders do not model the spikes directly, and hence may limit the processing time-scale of BMI control and adaptation. Moreover, while specialized CLDA techniques for intention estimation and assisted training exist, a unified and systematic CLDA framework that generalizes across different setups is lacking. Here we develop a novel closed-loop BMI training architecture that allows for processing, control, and adaptation using spike events, enables robust control and extends to various tasks. Moreover, we develop a unified control-theoretic CLDA framework within which intention estimation, assisted training, and adaptation are performed. The architecture incorporates an infinite-horizon optimal feedback-control (OFC) model of the brain’s behavior in closed-loop BMI control, and a point process model of spikes. The OFC model infers the user’s motor intention during CLDA—a process termed intention estimation. OFC is also used to design an autonomous and dynamic assisted training technique. The point process model allows for neural processing, control and decoder adaptation with every spike event and at a faster time-scale than current decoders; it also enables dynamic spike-event-based parameter adaptation unlike current CLDA methods that use batch-based adaptation on much slower adaptation time-scales. We conducted closed-loop experiments in a non-human primate over tens of days to dissociate the effects of these novel CLDA components. The OFC intention estimation improved BMI performance compared with current intention estimation techniques. OFC assisted training allowed the subject to consistently achieve proficient control. Spike-event-based adaptation resulted in faster and more consistent performance convergence compared with batch-based methods, and was robust to parameter initialization. Finally, the architecture extended control to tasks beyond those used for CLDA training. These results have significant implications towards the development of clinically-viable neuroprosthetics. PMID:27035820

A review and experimental study on the application of classifiers and evolutionary algorithms in EEG-based brain-machine interface systems

NASA Astrophysics Data System (ADS)

Tahernezhad-Javazm, Farajollah; Azimirad, Vahid; Shoaran, Maryam

2018-04-01

Objective. Considering the importance and the near-future development of noninvasive brain-machine interface (BMI) systems, this paper presents a comprehensive theoretical-experimental survey on the classification and evolutionary methods for BMI-based systems in which EEG signals are used. Approach. The paper is divided into two main parts. In the first part, a wide range of different types of the base and combinatorial classifiers including boosting and bagging classifiers and evolutionary algorithms are reviewed and investigated. In the second part, these classifiers and evolutionary algorithms are assessed and compared based on two types of relatively widely used BMI systems, sensory motor rhythm-BMI and event-related potentials-BMI. Moreover, in the second part, some of the improved evolutionary algorithms as well as bi-objective algorithms are experimentally assessed and compared. Main results. In this study two databases are used, and cross-validation accuracy (CVA) and stability to data volume (SDV) are considered as the evaluation criteria for the classifiers. According to the experimental results on both databases, regarding the base classifiers, linear discriminant analysis and support vector machines with respect to CVA evaluation metric, and naive Bayes with respect to SDV demonstrated the best performances. Among the combinatorial classifiers, four classifiers, Bagg-DT (bagging decision tree), LogitBoost, and GentleBoost with respect to CVA, and Bagging-LR (bagging logistic regression) and AdaBoost (adaptive boosting) with respect to SDV had the best performances. Finally, regarding the evolutionary algorithms, single-objective invasive weed optimization (IWO) and bi-objective nondominated sorting IWO algorithms demonstrated the best performances. Significance. We present a general survey on the base and the combinatorial classification methods for EEG signals (sensory motor rhythm and event-related potentials) as well as their optimization methods through the evolutionary algorithms. In addition, experimental and statistical significance tests are carried out to study the applicability and effectiveness of the reviewed methods.

An implantable integrated low-power amplifier-microelectrode array for Brain-Machine Interfaces.

PubMed

Patrick, Erin; Sankar, Viswanath; Rowe, William; Sanchez, Justin C; Nishida, Toshikazu

2010-01-01

One of the important challenges in designing Brain-Machine Interfaces (BMI) is to build implantable systems that have the ability to reliably process the activity of large ensembles of cortical neurons. In this paper, we report the design, fabrication, and testing of a polyimide-based microelectrode array integrated with a low-power amplifier as part of the Florida Wireless Integrated Recording Electrode (FWIRE) project at the University of Florida developing a fully implantable neural recording system for BMI applications. The electrode array was fabricated using planar micromachining MEMS processes and hybrid packaged with the amplifier die using a flip-chip bonding technique. The system was tested both on bench and in-vivo. Acute and chronic neural recordings were obtained from a rodent for a period of 42 days. The electrode-amplifier performance was analyzed over the chronic recording period with the observation of a noise floor of 4.5 microVrms, and an average signal-to-noise ratio of 3.8.

Single-trial dynamics of motor cortex and their applications to brain-machine interfaces

PubMed Central

Kao, Jonathan C.; Nuyujukian, Paul; Ryu, Stephen I.; Churchland, Mark M.; Cunningham, John P.; Shenoy, Krishna V.

2015-01-01

Increasing evidence suggests that neural population responses have their own internal drive, or dynamics, that describe how the neural population evolves through time. An important prediction of neural dynamical models is that previously observed neural activity is informative of noisy yet-to-be-observed activity on single-trials, and may thus have a denoising effect. To investigate this prediction, we built and characterized dynamical models of single-trial motor cortical activity. We find these models capture salient dynamical features of the neural population and are informative of future neural activity on single trials. To assess how neural dynamics may beneficially denoise single-trial neural activity, we incorporate neural dynamics into a brain–machine interface (BMI). In online experiments, we find that a neural dynamical BMI achieves substantially higher performance than its non-dynamical counterpart. These results provide evidence that neural dynamics beneficially inform the temporal evolution of neural activity on single trials and may directly impact the performance of BMIs. PMID:26220660

Facilitating Factors and Barriers to BMI Screening in Schools

ERIC Educational Resources Information Center

Stalter, Ann M.; Chaudry, Rosemary V.; Polivka, Barbara J.

2010-01-01

The National Association of School Nurses advocates for body mass index (BMI) screening. Little research describes school nurse practice of BMI screening. In this descriptive study, 25 Ohio school nurses participated in three focus groups. An adapted "Healthy People 2010" Determinants of Health Model guided the research questions. School…

Feedback for reinforcement learning based brain-machine interfaces using confidence metrics.

PubMed

Prins, Noeline W; Sanchez, Justin C; Prasad, Abhishek

2017-06-01

For brain-machine interfaces (BMI) to be used in activities of daily living by paralyzed individuals, the BMI should be as autonomous as possible. One of the challenges is how the feedback is extracted and utilized in the BMI. Our long-term goal is to create autonomous BMIs that can utilize an evaluative feedback from the brain to update the decoding algorithm and use it intelligently in order to adapt the decoder. In this study, we show how to extract the necessary evaluative feedback from a biologically realistic (synthetic) source, use both the quantity and the quality of the feedback, and how that feedback information can be incorporated into a reinforcement learning (RL) controller architecture to maximize its performance. Motivated by the perception-action-reward cycle (PARC) in the brain which links reward for cognitive decision making and goal-directed behavior, we used a reward-based RL architecture named Actor-Critic RL as the model. Instead of using an error signal towards building an autonomous BMI, we envision to use a reward signal from the nucleus accumbens (NAcc) which plays a key role in the linking of reward to motor behaviors. To deal with the complexity and non-stationarity of biological reward signals, we used a confidence metric which was used to indicate the degree of feedback accuracy. This confidence was added to the Actor's weight update equation in the RL controller architecture. If the confidence was high (>0.2), the BMI decoder used this feedback to update its parameters. However, when the confidence was low, the BMI decoder ignored the feedback and did not update its parameters. The range between high confidence and low confidence was termed as the 'ambiguous' region. When the feedback was within this region, the BMI decoder updated its weight at a lower rate than when fully confident, which was decided by the confidence. We used two biologically realistic models to generate synthetic data for MI (Izhikevich model) and NAcc (Humphries model) to validate proposed controller architecture. In this work, we show how the overall performance of the BMI was improved by using a threshold close to the decision boundary to reject erroneous feedback. Additionally, we show the stability of the system improved when the feedback was used with a threshold. The result of this study is a step towards making BMIs autonomous. While our method is not fully autonomous, the results demonstrate that extensive training times necessary at the beginning of each BMI session can be significantly decreased. In our approach, decoder training time was only limited to 10 trials in the first BMI session. Subsequent sessions used previous session weights to initialize the decoder. We also present a method where the use of a threshold can be applied to any decoder with a feedback signal that is less than perfect so that erroneous feedback can be avoided and the stability of the system can be increased.

Feedback for reinforcement learning based brain-machine interfaces using confidence metrics

NASA Astrophysics Data System (ADS)

Prins, Noeline W.; Sanchez, Justin C.; Prasad, Abhishek

2017-06-01

Objective. For brain-machine interfaces (BMI) to be used in activities of daily living by paralyzed individuals, the BMI should be as autonomous as possible. One of the challenges is how the feedback is extracted and utilized in the BMI. Our long-term goal is to create autonomous BMIs that can utilize an evaluative feedback from the brain to update the decoding algorithm and use it intelligently in order to adapt the decoder. In this study, we show how to extract the necessary evaluative feedback from a biologically realistic (synthetic) source, use both the quantity and the quality of the feedback, and how that feedback information can be incorporated into a reinforcement learning (RL) controller architecture to maximize its performance. Approach. Motivated by the perception-action-reward cycle (PARC) in the brain which links reward for cognitive decision making and goal-directed behavior, we used a reward-based RL architecture named Actor-Critic RL as the model. Instead of using an error signal towards building an autonomous BMI, we envision to use a reward signal from the nucleus accumbens (NAcc) which plays a key role in the linking of reward to motor behaviors. To deal with the complexity and non-stationarity of biological reward signals, we used a confidence metric which was used to indicate the degree of feedback accuracy. This confidence was added to the Actor’s weight update equation in the RL controller architecture. If the confidence was high (>0.2), the BMI decoder used this feedback to update its parameters. However, when the confidence was low, the BMI decoder ignored the feedback and did not update its parameters. The range between high confidence and low confidence was termed as the ‘ambiguous’ region. When the feedback was within this region, the BMI decoder updated its weight at a lower rate than when fully confident, which was decided by the confidence. We used two biologically realistic models to generate synthetic data for MI (Izhikevich model) and NAcc (Humphries model) to validate proposed controller architecture. Main results. In this work, we show how the overall performance of the BMI was improved by using a threshold close to the decision boundary to reject erroneous feedback. Additionally, we show the stability of the system improved when the feedback was used with a threshold. Significance: The result of this study is a step towards making BMIs autonomous. While our method is not fully autonomous, the results demonstrate that extensive training times necessary at the beginning of each BMI session can be significantly decreased. In our approach, decoder training time was only limited to 10 trials in the first BMI session. Subsequent sessions used previous session weights to initialize the decoder. We also present a method where the use of a threshold can be applied to any decoder with a feedback signal that is less than perfect so that erroneous feedback can be avoided and the stability of the system can be increased.

Motor imaginary-based brain-machine interface design using programmable logic controllers for the disabled.

PubMed

Jeyabalan, Vickneswaran; Samraj, Andrews; Loo, Chu Kiong

2010-10-01

Aiming at the implementation of brain-machine interfaces (BMI) for the aid of disabled people, this paper presents a system design for real-time communication between the BMI and programmable logic controllers (PLCs) to control an electrical actuator that could be used in devices to help the disabled. Motor imaginary signals extracted from the brain’s motor cortex using an electroencephalogram (EEG) were used as a control signal. The EEG signals were pre-processed by means of adaptive recursive band-pass filtrations (ARBF) and classified using simplified fuzzy adaptive resonance theory mapping (ARTMAP) in which the classified signals are then translated into control signals used for machine control via the PLC. A real-time test system was designed using MATLAB for signal processing, KEP-Ware V4 OLE for process control (OPC), a wireless local area network router, an Omron Sysmac CPM1 PLC and a 5 V/0.3A motor. This paper explains the signal processing techniques, the PLC's hardware configuration, OPC configuration and real-time data exchange between MATLAB and PLC using the MATLAB OPC toolbox. The test results indicate that the function of exchanging real-time data can be attained between the BMI and PLC through OPC server and proves that it is an effective and feasible method to be applied to devices such as wheelchairs or electronic equipment.

The usefulness of "corrected" body mass index vs. self-reported body mass index: comparing the population distributions, sensitivity, specificity, and predictive utility of three correction equations using Canadian population-based data.

PubMed

Dutton, Daniel J; McLaren, Lindsay

2014-05-06

National data on body mass index (BMI), computed from self-reported height and weight, is readily available for many populations including the Canadian population. Because self-reported weight is found to be systematically under-reported, it has been proposed that the bias in self-reported BMI can be corrected using equations derived from data sets which include both self-reported and measured height and weight. Such correction equations have been developed and adopted. We aim to evaluate the usefulness (i.e., distributional similarity; sensitivity and specificity; and predictive utility vis-à-vis disease outcomes) of existing and new correction equations in population-based research. The Canadian Community Health Surveys from 2005 and 2008 include both measured and self-reported values of height and weight, which allows for construction and evaluation of correction equations. We focused on adults age 18-65, and compared three correction equations (two correcting weight only, and one correcting BMI) against self-reported and measured BMI. We first compared population distributions of BMI. Second, we compared the sensitivity and specificity of self-reported BMI and corrected BMI against measured BMI. Third, we compared the self-reported and corrected BMI in terms of association with health outcomes using logistic regression. All corrections outperformed self-report when estimating the full BMI distribution; the weight-only correction outperformed the BMI-only correction for females in the 23-28 kg/m2 BMI range. In terms of sensitivity/specificity, when estimating obesity prevalence, corrected values of BMI (from any equation) were superior to self-report. In terms of modelling BMI-disease outcome associations, findings were mixed, with no correction proving consistently superior to self-report. If researchers are interested in modelling the full population distribution of BMI, or estimating the prevalence of obesity in a population, then a correction of any kind included in this study is recommended. If the researcher is interested in using BMI as a predictor variable for modelling disease, then both self-reported and corrected BMI result in biased estimates of association.

Associations between maternal early pregnancy body mass index (BMI) and placental DNA methylation at term

USDA-ARS?s Scientific Manuscript database

The placenta serves as the definitive maternal-fetal interface and mediates exchange of nutrients, gases, and waste between mother and the developing fetus. The placenta integrates signals from both mother and baby, coordinating maternal nutrient supply with fetal demand and development. In epidemio...

Simultaneous Scalp Electroencephalography (EEG), Electromyography (EMG), and Whole-body Segmental Inertial Recording for Multi-modal Neural Decoding

PubMed Central

Bulea, Thomas C.; Kilicarslan, Atilla; Ozdemir, Recep; Paloski, William H.; Contreras-Vidal, Jose L.

2013-01-01

Recent studies support the involvement of supraspinal networks in control of bipedal human walking. Part of this evidence encompasses studies, including our previous work, demonstrating that gait kinematics and limb coordination during treadmill walking can be inferred from the scalp electroencephalogram (EEG) with reasonably high decoding accuracies. These results provide impetus for development of non-invasive brain-machine-interface (BMI) systems for use in restoration and/or augmentation of gait- a primary goal of rehabilitation research. To date, studies examining EEG decoding of activity during gait have been limited to treadmill walking in a controlled environment. However, to be practically viable a BMI system must be applicable for use in everyday locomotor tasks such as over ground walking and turning. Here, we present a novel protocol for non-invasive collection of brain activity (EEG), muscle activity (electromyography (EMG)), and whole-body kinematic data (head, torso, and limb trajectories) during both treadmill and over ground walking tasks. By collecting these data in the uncontrolled environment insight can be gained regarding the feasibility of decoding unconstrained gait and surface EMG from scalp EEG. PMID:23912203

Reversible large–scale modification of cortical networks during neuroprosthetic control

PubMed Central

Ganguly, Karunesh; Wallis, Jonathan D.

2012-01-01

Brain-Machine Interfaces (BMI) provide a framework to study cortical dynamics and the neural correlates of learning. Neuroprosthetic control has been associated with tuning changes in specific neurons directly projecting to the BMI (hereafter ‘direct neurons’). However, little is known about the larger network dynamics. By monitoring ensembles of neurons that were either causally linked to BMI control or indirectly involved, here we show that proficient neuroprosthetic control is associated with large-scale modifications to the cortical network in macaque monkeys. Specifically, there were changes in the preferred direction of both direct and indirect neurons. Interestingly, with learning, there was a relative decrease in the net modulation of indirect neural activity in comparison to the direct activity. These widespread differential changes in the direct and indirect population activity were remarkably stable from one day to the next and readily coexisted with the long-standing cortical network for upper limb control. Thus, the process of learning BMI control is associated with differential modification of neural populations based on their specific relation to movement control. PMID:21499255

A cognitive neuroprosthetic that uses cortical stimulation for somatosensory feedback

PubMed Central

Klaes, Christian; Shi, Ying; Kellis, Spencer; Minxha, Juri; Revechkis, Boris; Andersen, Richard A.

2015-01-01

Present day cortical brain machine interfaces (BMI) have made impressive advances using decoded brain signals to control extracorporeal devices. Although BMIs are used in a closed-loop fashion, sensory feedback typically is visual only. However medical case studies have shown that the loss of somesthesis in a limb greatly reduces the agility of the limb even when visual feedback is available (for review see Robles-De-La-Torre, 2006). To overcome this limitation, this study tested a closed-loop BMI that utilizes intracortical microstimulation (ICMS) to provide ‘tactile’ sensation to a non-human primate (NHP). Using stimulation electrodes in Brodmann area 1 of somatosensory cortex (BA1) and recording electrodes in the anterior intraparietal area (AIP), the parietal reach region (PRR) and dorsal area 5 (area 5d), it was found that this form of feedback can be used in BMI tasks. PMID:25242377

Observation-based training for neuroprosthetic control of grasping by amputees.

PubMed

Agashe, Harshavardhan A; Contreras-Vidal, Jose L

2014-01-01

Current brain-machine interfaces (BMIs) allow upper limb amputees to position robotic arms with a high degree of accuracy, but lack the ability to control hand pre-shaping for grasping different objects. We have previously shown that low frequency (0.1-1 Hz) time domain cortical activity recorded at the scalp via electroencephalography (EEG) encodes information about grasp pre-shaping. To transfer this technology to clinical populations such as amputees, the challenge lies in constructing BMI models in the absence of overt training hand movements. Here we show that it is possible to train BMI models using observed grasping movements performed by a robotic hand attached to amputees' residual limb. Three transradial amputees controlled the grasping motion of an attached robotic hand via their EEG, following the action-observation training phase. Over multiple sessions, subjects successfully grasped the presented object (a bottle or a credit card) in 53±16 % of trials, demonstrating the validity of the BMI models. Importantly, the validation of the BMI model was through closed-loop performance, which demonstrates generalization of the model to unseen data. These results suggest `mirror neuron system' properties captured by delta band EEG that allows neural representation for action observation to be used for action control in an EEG-based BMI system.

Brain-machine interfaces for controlling lower-limb powered robotic systems.

PubMed

He, Yongtian; Eguren, David; Azorín, José M; Grossman, Robert G; Luu, Trieu Phat; Contreras-Vidal, Jose L

2018-04-01

Lower-limb, powered robotics systems such as exoskeletons and orthoses have emerged as novel robotic interventions to assist or rehabilitate people with walking disabilities. These devices are generally controlled by certain physical maneuvers, for example pressing buttons or shifting body weight. Although effective, these control schemes are not what humans naturally use. The usability and clinical relevance of these robotics systems could be further enhanced by brain-machine interfaces (BMIs). A number of preliminary studies have been published on this topic, but a systematic understanding of the experimental design, tasks, and performance of BMI-exoskeleton systems for restoration of gait is lacking. To address this gap, we applied standard systematic review methodology for a literature search in PubMed and EMBASE databases and identified 11 studies involving BMI-robotics systems. The devices, user population, input and output of the BMIs and robot systems respectively, neural features, decoders, denoising techniques, and system performance were reviewed and compared. Results showed BMIs classifying walk versus stand tasks are the most common. The results also indicate that electroencephalography (EEG) is the only recording method for humans. Performance was not clearly presented in most of the studies. Several challenges were summarized, including EEG denoising, safety, responsiveness and others. We conclude that lower-body powered exoskeletons with automated gait intention detection based on BMIs open new possibilities in the assistance and rehabilitation fields, although the current performance, clinical benefits and several key challenging issues indicate that additional research and development is required to deploy these systems in the clinic and at home. Moreover, rigorous EEG denoising techniques, suitable performance metrics, consistent trial reporting, and more clinical trials are needed to advance the field.

Brain-machine interfaces for controlling lower-limb powered robotic systems

NASA Astrophysics Data System (ADS)

He, Yongtian; Eguren, David; Azorín, José M.; Grossman, Robert G.; Phat Luu, Trieu; Contreras-Vidal, Jose L.

2018-04-01

Objective. Lower-limb, powered robotics systems such as exoskeletons and orthoses have emerged as novel robotic interventions to assist or rehabilitate people with walking disabilities. These devices are generally controlled by certain physical maneuvers, for example pressing buttons or shifting body weight. Although effective, these control schemes are not what humans naturally use. The usability and clinical relevance of these robotics systems could be further enhanced by brain-machine interfaces (BMIs). A number of preliminary studies have been published on this topic, but a systematic understanding of the experimental design, tasks, and performance of BMI-exoskeleton systems for restoration of gait is lacking. Approach. To address this gap, we applied standard systematic review methodology for a literature search in PubMed and EMBASE databases and identified 11 studies involving BMI-robotics systems. The devices, user population, input and output of the BMIs and robot systems respectively, neural features, decoders, denoising techniques, and system performance were reviewed and compared. Main results. Results showed BMIs classifying walk versus stand tasks are the most common. The results also indicate that electroencephalography (EEG) is the only recording method for humans. Performance was not clearly presented in most of the studies. Several challenges were summarized, including EEG denoising, safety, responsiveness and others. Significance. We conclude that lower-body powered exoskeletons with automated gait intention detection based on BMIs open new possibilities in the assistance and rehabilitation fields, although the current performance, clinical benefits and several key challenging issues indicate that additional research and development is required to deploy these systems in the clinic and at home. Moreover, rigorous EEG denoising techniques, suitable performance metrics, consistent trial reporting, and more clinical trials are needed to advance the field.

Detection of Error Related Neuronal Responses Recorded by Electrocorticography in Humans during Continuous Movements

PubMed Central

Milekovic, Tomislav; Ball, Tonio; Schulze-Bonhage, Andreas; Aertsen, Ad; Mehring, Carsten

2013-01-01

Background Brain-machine interfaces (BMIs) can translate the neuronal activity underlying a user’s movement intention into movements of an artificial effector. In spite of continuous improvements, errors in movement decoding are still a major problem of current BMI systems. If the difference between the decoded and intended movements becomes noticeable, it may lead to an execution error. Outcome errors, where subjects fail to reach a certain movement goal, are also present during online BMI operation. Detecting such errors can be beneficial for BMI operation: (i) errors can be corrected online after being detected and (ii) adaptive BMI decoding algorithm can be updated to make fewer errors in the future. Methodology/Principal Findings Here, we show that error events can be detected from human electrocorticography (ECoG) during a continuous task with high precision, given a temporal tolerance of 300–400 milliseconds. We quantified the error detection accuracy and showed that, using only a small subset of 2×2 ECoG electrodes, 82% of detection information for outcome error and 74% of detection information for execution error available from all ECoG electrodes could be retained. Conclusions/Significance The error detection method presented here could be used to correct errors made during BMI operation or to adapt a BMI algorithm to make fewer errors in the future. Furthermore, our results indicate that smaller ECoG implant could be used for error detection. Reducing the size of an ECoG electrode implant used for BMI decoding and error detection could significantly reduce the medical risk of implantation. PMID:23383315

Representativeness and optimal use of body mass index (BMI) in the UK Clinical Practice Research Datalink (CPRD)

PubMed Central

Bhaskaran, Krishnan; Forbes, Harriet J; Douglas, Ian; Leon, David A; Smeeth, Liam

2013-01-01

Objectives To assess the completeness and representativeness of body mass index (BMI) data in the Clinical Practice Research Datalink (CPRD), and determine an optimal strategy for their use. Design Descriptive study. Setting Electronic healthcare records from primary care. Participants A million patient random sample from the UK CPRD primary care database, aged ≥16 years. Primary and secondary outcome measures BMI completeness in CPRD was evaluated by age, sex and calendar period. CPRD-based summary BMI statistics for each calendar year (2003–2010) were age-standardised and sex-standardised and compared with equivalent statistics from the Health Survey for England (HSE). Results BMI completeness increased over calendar time from 37% in 1990–1994 to 77% in 2005–2011, was higher among females and increased with age. When BMI at specific time points was assigned based on the most recent record, calendar–year-specific mean BMI statistics underestimated equivalent HSE statistics by 0.75–1.1 kg/m2. Restriction to those with a recent (≤3 years) BMI resulted in mean BMI estimates closer to HSE (≤0.28 kg/m2 underestimation), but excluded up to 47% of patients. An alternative strategy of imputing up-to-date BMI based on modelled changes in BMI over time since the last available record also led to mean BMI estimates that were close to HSE (≤0.37 kg/m2 underestimation). Conclusions Completeness of BMI in CPRD increased over time and varied by age and sex. At a given point in time, a large proportion of the most recent BMIs are unlikely to reflect current BMI; consequent BMI misclassification might be reduced by employing model-based imputation of current BMI. PMID:24038008

The usefulness of “corrected” body mass index vs. self-reported body mass index: comparing the population distributions, sensitivity, specificity, and predictive utility of three correction equations using Canadian population-based data

PubMed Central

2014-01-01

Background National data on body mass index (BMI), computed from self-reported height and weight, is readily available for many populations including the Canadian population. Because self-reported weight is found to be systematically under-reported, it has been proposed that the bias in self-reported BMI can be corrected using equations derived from data sets which include both self-reported and measured height and weight. Such correction equations have been developed and adopted. We aim to evaluate the usefulness (i.e., distributional similarity; sensitivity and specificity; and predictive utility vis-à-vis disease outcomes) of existing and new correction equations in population-based research. Methods The Canadian Community Health Surveys from 2005 and 2008 include both measured and self-reported values of height and weight, which allows for construction and evaluation of correction equations. We focused on adults age 18–65, and compared three correction equations (two correcting weight only, and one correcting BMI) against self-reported and measured BMI. We first compared population distributions of BMI. Second, we compared the sensitivity and specificity of self-reported BMI and corrected BMI against measured BMI. Third, we compared the self-reported and corrected BMI in terms of association with health outcomes using logistic regression. Results All corrections outperformed self-report when estimating the full BMI distribution; the weight-only correction outperformed the BMI-only correction for females in the 23–28 kg/m2 BMI range. In terms of sensitivity/specificity, when estimating obesity prevalence, corrected values of BMI (from any equation) were superior to self-report. In terms of modelling BMI-disease outcome associations, findings were mixed, with no correction proving consistently superior to self-report. Conclusions If researchers are interested in modelling the full population distribution of BMI, or estimating the prevalence of obesity in a population, then a correction of any kind included in this study is recommended. If the researcher is interested in using BMI as a predictor variable for modelling disease, then both self-reported and corrected BMI result in biased estimates of association. PMID:24885210

Development of an implantable wireless ECoG 128ch recording device for clinical brain machine interface.

PubMed

Matsushita, Kojiro; Hirata, Masayuki; Suzuki, Takafumi; Ando, Hiroshi; Ota, Yuki; Sato, Fumihiro; Morris, Shyne; Yoshida, Takeshi; Matsuki, Hidetoshi; Yoshimine, Toshiki

2013-01-01

Brain Machine Interface (BMI) is a system that assumes user's intention by analyzing user's brain activities and control devices with the assumed intention. It is considered as one of prospective tools to enhance paralyzed patients' quality of life. In our group, we especially focus on ECoG (electro-corti-gram)-BMI, which requires surgery to place electrodes on the cortex. We try to implant all the devices within the patient's head and abdomen and to transmit the data and power wirelessly. Our device consists of 5 parts: (1) High-density multi-electrodes with a 3D shaped sheet fitting to the individual brain surface to effectively record the ECoG signals; (2) A small circuit board with two integrated circuit chips functioning 128 [ch] analogue amplifiers and A/D converters for ECoG signals; (3) A Wifi data communication & control circuit with the target PC; (4) A non-contact power supply transmitting electrical power minimum 400[mW] to the device 20[mm] away. We developed those devices, integrated them, and, investigated the performance.

Time trends and factors in body mass index and obesity among children in China: 1997-2011.

PubMed

Wang, H; Xue, H; Du, S; Zhang, J; Wang, Y; Zhang, B

2017-06-01

Research on the shift in children's body mass index (BMI) distribution is limited and conditional mean models used in the previous research have limitations in capturing cross-distribution variations in effects. The objectives are to analyze the shift in Chinese children's BMI distribution and to test the associations between BMI distribution and other factors. We analyzed data collected from children 7 to 17 years old from the China Health and Nutrition Survey (CHNS) conducted in 1997, 2000, 2004, 2006, 2009 and 2011, from 2814 participants with 6799 observations. Longitudinal quantile regression (QR) was used to explore the effect of several factors on BMI trends in 2015. The BMI curves shift to the right in boys and girls, with the distributions becoming wider, indicating a higher proportion of children have become overweight. The 5th, 15th, 50th, 85th and 95th BMI percentile curves all shifted upward from 1997 to 2011, and the higher percentiles had greater increases. The prevalence of overweight and obesity increased in boys and girls between 1997 and 2011, from 6.5 to 15.5% in boys and from 4.6 to 10.4% in girls. Energy intake and parents' BMI levels had a positive association with children's BMI. Per capita income was positively associated with changes in BMI only at the upper percentiles of the BMI distributions in boys. Increased physical activity (PA) was associated with decreased BMI in girls. Children in China are becoming increasingly overweight. Energy intake, parental BMI, PA and early menarche age in girls are associated with elevated BMI in children.

Transmission of wireless neural signals through a 0.18 µm CMOS low-power amplifier.

PubMed

Gazziro, M; Braga, C F R; Moreira, D A; Carvalho, A C P L F; Rodrigues, J F; Navarro, J S; Ardila, J C M; Mioni, D P; Pessatti, M; Fabbro, P; Freewin, C; Saddow, S E

2015-01-01

In the field of Brain Machine Interfaces (BMI) researchers still are not able to produce clinically viable solutions that meet the requirements of long-term operation without the use of wires or batteries. Another problem is neural compatibility with the electrode probes. One of the possible ways of approaching these problems is the use of semiconductor biocompatible materials (silicon carbide) combined with an integrated circuit designed to operate with low power consumption. This paper describes a low-power neural signal amplifier chip, named Cortex, fabricated using 0.18 μm CMOS process technology with all electronics integrated in an area of 0.40 mm(2). The chip has 4 channels, total power consumption of only 144 μW, and is impedance matched to silicon carbide biocompatible electrodes.

Global burden of cancer attributable to high body-mass index in 2012: a population-based study

PubMed Central

Byrnes, Graham; Renehan, Prof Andrew G; Stevens, Gretchen A; Ezzati, Prof Majid; Ferlay, Jacques; Miranda, J. Jaime; Romieu, Isabelle; Dikshit, Rajesh; Forman, David; Soerjomataram, Isabelle

2015-01-01

Background Excess body mass index (BMI) is associated with increased risk of cancer. To inform public health policyand future research, we estimated the global burden of cancer attributable to excess BMI. Methods Population attributable fractions (PAFs) were derived using relative risks and BMI estimates in adults by age, sex and country. Assuming a10-year lag-period, PAFs were calculated using BMI estimates in 2002. GLOBOCAN2012 was used to compute numbers of new cancer cases attributable to excess BMI. In an alternative scenario, we computed the proportion of potentially avoidable cancers assuming that populations maintained their BMI-level observed in 1982. Secondary analyses were performed to test the model and estimate the impactof hormone replacement therapy (HRT) and smoking. Findings Worldwide, we estimated that 481,000 or 3·6% of all new cancer cases in 2012 were attributable to excess BMI. PAFs were greater in women compared with men (5·4% versus 1·9%). The burden was concentrated in countries with very high and high human development index (HDI, PAF: 5·3% and 4·8%) compared with countries with moderate and low HDI (PAF: 1·6% and 1·0%). Corpus uteri, post-menopausal breast and colon cancers accounted for approximately two-thirds (64%) of excess BMI attributable cancers. One fourth (~118,000) of all cases related to excess BMI in 2012 could be attributed to the rising BMI since 1982. Interpretation These findings further underpin the need for a global effort to abate the rising trends in population-level excess weight. Assuming that the relationship between excess BMI and cancer is causal and the current pattern of population weight gain continues, this will likely augment the future burden of cancer. Funding World Cancer Research Fund, Marie Currie Fellowship, the National Health and Medical Research Council Australia and US NIH. PMID:25467404

Neural Coding for Effective Rehabilitation

PubMed Central

2014-01-01

Successful neurological rehabilitation depends on accurate diagnosis, effective treatment, and quantitative evaluation. Neural coding, a technology for interpretation of functional and structural information of the nervous system, has contributed to the advancements in neuroimaging, brain-machine interface (BMI), and design of training devices for rehabilitation purposes. In this review, we summarized the latest breakthroughs in neuroimaging from microscale to macroscale levels with potential diagnostic applications for rehabilitation. We also reviewed the achievements in electrocorticography (ECoG) coding with both animal models and human beings for BMI design, electromyography (EMG) interpretation for interaction with external robotic systems, and robot-assisted quantitative evaluation on the progress of rehabilitation programs. Future rehabilitation would be more home-based, automatic, and self-served by patients. Further investigations and breakthroughs are mainly needed in aspects of improving the computational efficiency in neuroimaging and multichannel ECoG by selection of localized neuroinformatics, validation of the effectiveness in BMI guided rehabilitation programs, and simplification of the system operation in training devices. PMID:25258708

A cognitive neuroprosthetic that uses cortical stimulation for somatosensory feedback.

PubMed

Klaes, Christian; Shi, Ying; Kellis, Spencer; Minxha, Juri; Revechkis, Boris; Andersen, Richard A

2014-10-01

Present day cortical brain-machine interfaces (BMIs) have made impressive advances using decoded brain signals to control extracorporeal devices. Although BMIs are used in a closed-loop fashion, sensory feedback typically is visual only. However medical case studies have shown that the loss of somesthesis in a limb greatly reduces the agility of the limb even when visual feedback is available. To overcome this limitation, this study tested a closed-loop BMI that utilizes intracortical microstimulation to provide 'tactile' sensation to a non-human primate. Using stimulation electrodes in Brodmann area 1 of somatosensory cortex (BA1) and recording electrodes in the anterior intraparietal area, the parietal reach region and dorsal area 5 (area 5d), it was found that this form of feedback can be used in BMI tasks. Providing somatosensory feedback has the poyential to greatly improve the performance of cognitive neuroprostheses especially for fine control and object manipulation. Adding stimulation to a BMI system could therefore improve the quality of life for severely paralyzed patients.

Investigation of Implantable Multi-Channel Electrode Array in Rat Cerebral Cortex Used for Recording

NASA Astrophysics Data System (ADS)

Taniguchi, Noriyuki; Fukayama, Osamu; Suzuki, Takafumi; Mabuchi, Kunihiko

There have recently been many studies concerning the control of robot movements using neural signals recorded from the brain (usually called the Brain-Machine interface (BMI)). We fabricated implantable multi-electrode arrays to obtain neural signals from the rat cerebral cortex. As any multi-electrode array should have electrode alignment that minimizes invasion, it is necessary to customize the recording site. We designed three types of 22-channel multi-electrode arrays, i.e., 1) wide, 2) three-layered, and 3) separate. The first extensively covers the cerebral cortex. The second has a length of 2 mm, which can cover the area of the primary motor cortex. The third array has a separate structure, which corresponds to the position of the forelimb and hindlimb areas of the primary motor cortex. These arrays were implanted into the cerebral cortex of a rat. We estimated the walking speed from neural signals using our fabricated three-layered array to investigate its feasibility for BMI research. The neural signal of the rat and its walking speed were simultaneously recorded. The results revealed that evaluation using either the anterior electrode group or posterior group provided accurate estimates. However, two electrode groups around the center yielded poor estimates although it was possible to record neural signals.

Thermal oxidation induced degradation of carbon fiber reinforced composites and carbon nanotube sheet enhanced fiber/matrix interface for high temperature aerospace structural applications

NASA Astrophysics Data System (ADS)

Haque, Mohammad Hamidul

Recent increase in the use of carbon fiber reinforced polymer matrix composite, especially for high temperature applications in aerospace primary and secondary structures along with wind energy and automotive industries, have generated new challenges to predict its failure mechanisms and service life. This dissertation reports the experimental study of a unidirectional carbon fiber reinforced bismaleimide (BMI) composites (CFRC), an excellent candidate for high temperature aerospace components, undergoing thermal oxidation at 260 °C in air for over 3000 hours. The key focus of the work is to investigate the mechanical properties of the carbon fiber BMI composite subjected to thermal aging in three key aspects - first, studying its bulk flexural properties (in macro scale), second, characterizing the crack propagation along the fiber direction, representing the interfacial bonding strength between fiber and matrix (in micro scale), and third, introducing nano-structured materials to modify the interface (in nano scale) between the carbon fiber and BMI resin and mechanical characterization to study its influence on mitigating the aging effect. Under the first category, weight loss and flexural properties have been monitored as the oxidation propagates through the fiber/matrix interface. Dynamic mechanical analysis and micro-computed tomography analysis have been performed to analyze the aging effects. In the second category, the long-term effects of thermal oxidation on the delamination (between the composite plies) and debonding (between fiber and matrix) type fracture toughness have been characterized by preparing two distinct types of double cantilever beam specimens. Digital image correlation has been used to determine the deformation field and strain distribution around the crack propagation path. Finally the resin system and the fiber/matrix interface have been modified using nanomaterials to mitigate the degradations caused by oxidation. Nanoclay modified epoxy resin has been characterized for hardness and modulus using nanoindentation technique. A significant reduction of oxidation, which is anticipated to eventually translate into improvement in mechanical properties, has been observed as the nanoclay particles have worked as a retarding agent for the oxidation propagation. Carbon nanotube sheet scrolled carbon fiber tows embedded in epoxy matrix have been investigated for interfacial properties using nanoindentation (push-out test), in micro scale, and using tensile testing (pull-out test), in macro scale. A significant increase in interfacial shear strength has been achieved by this unique materials combination.

A Python Interface for the Dakota Iterative Systems Analysis Toolkit

NASA Astrophysics Data System (ADS)

Piper, M.; Hutton, E.; Syvitski, J. P.

2016-12-01

Uncertainty quantification is required to improve the accuracy, reliability, and accountability of Earth science models. Dakota is a software toolkit, developed at Sandia National Laboratories, that provides an interface between models and a library of analysis methods, including support for sensitivity analysis, uncertainty quantification, optimization, and calibration techniques. Dakota is a powerful tool, but its learning curve is steep: the user not only must understand the structure and syntax of the Dakota input file, but also must develop intermediate code, called an analysis driver, that allows Dakota to run a model. The CSDMS Dakota interface (CDI) is a Python package that wraps and extends Dakota's user interface. It simplifies the process of configuring and running a Dakota experiment. A user can program to the CDI, allowing a Dakota experiment to be scripted. The CDI creates Dakota input files and provides a generic analysis driver. Any model written in Python that exposes a Basic Model Interface (BMI), as well as any model componentized in the CSDMS modeling framework, automatically works with the CDI. The CDI has a plugin architecture, so models written in other languages, or those that don't expose a BMI, can be accessed by the CDI by programmatically extending a template; an example is provided in the CDI distribution. Currently, six Dakota analysis methods have been implemented for examples from the much larger Dakota library. To demonstrate the CDI, we performed an uncertainty quantification experiment with the HydroTrend hydrological water balance and transport model. In the experiment, we evaluated the response of long-term suspended sediment load at the river mouth (Qs) to uncertainty in two input parameters, annual mean temperature (T) and precipitation (P), over a series of 100-year runs, using the polynomial chaos method. Through Dakota, we calculated moments, local and global (Sobol') sensitivity indices, and probability density and cumulative distribution functions for the response.

Impulsivity as a moderator of the associations between child maltreatment types and body mass index.

PubMed

Brown, Shaquanna; Mitchell, Tarrah B; Fite, Paula J; Bortolato, Marco

2017-05-01

Child maltreatment has emerged as an important risk factor for adult obesity (Danese & Tan, 2014; Hemmingsson et al., 2014). However, there is a need for research delineating the factors that play a role in this association. Impulsivity has been shown to be associated with both child maltreatment (Brodsky et al., 2001) and body mass index (BMI; Cortese et al., 2008; Thamotharan et al., 2013). Further, given previous research showing that adverse events interact with impulsivity to predict hazardous drinking behaviors (Fox et al., 2010), there is reason to hypothesize that child maltreatment might interact with impulsivity to predict other adverse health outcomes, such as elevated BMI. Accordingly, the current study examined whether impulsivity moderated the association between child maltreatment types (i.e., physical abuse, physical neglect, sexual abuse, emotional abuse, and emotional neglect) and BMI. The sample was comprised of 500 undergraduate students (49.6% male) between the ages of 18 and 25 years. Regression analyses suggested that maltreatment types and impulsivity were not uniquely associated with BMI. However, impulsivity moderated the association between childhood sexual abuse and adult BMI, such that BMI was highest at high levels of both sexual abuse and impulsivity. Impulsivity did not moderate the associations between the other child maltreatment types and BMI. Limitations, future directions, and clinical implications of this research are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Impulsivity as a moderator of the associations between child maltreatment types and body mass index

PubMed Central

Brown, Shaquanna; Mitchell, Tarrah B.; Fite, Paula J.; Bortolato, Marco

2017-01-01

Child maltreatment has emerged as an important risk factor for adult obesity (Danese & Tan, 2014; Hemmingsson, Johannsson, & Reynisdottir, 2014). However, there is a need for research delineating the factors that play a role in this association. Impulsivity has been shown to be associated with both child maltreatment (Ouyang, Fang, Mercy, Perou, & Grosse, 2008) and body mass index (BMI; Cortese et al., 2008; Thamotharan, Lange, Zale, Huffhines, & Fields, 2013). Further, given previous research showing that adverse events interact with impulsivity to predict hazardous drinking behaviors (Fox, Bergquist, Gu, & Sinha, 2010), there is reason to hypothesize that child maltreatment might interact with impulsivity to predict other adverse health outcomes, such as elevated BMI. Accordingly, the current study examined whether impulsivity moderated the association between child maltreatment types (i.e., physical abuse, physical neglect, sexual abuse, emotional abuse, and emotional neglect) and BMI. The sample was comprised of 500 undergraduate students (49.6% male) between the ages of 18 and 25 years. Regression analyses suggested that maltreatment types and impulsivity were not uniquely associated with BMI. However, impulsivity moderated the association between childhood sexual abuse and adult BMI, such that BMI was highest at high levels of both sexual abuse and impulsivity. Impulsivity did not moderate the associations between the other child maltreatment types and BMI. Limitations, future directions, and clinical implications of this research are discussed. PMID:28262605

A Brain-Machine Interface Instructed by Direct Intracortical Microstimulation

PubMed Central

O'Doherty, Joseph E.; Lebedev, Mikhail A.; Hanson, Timothy L.; Fitzsimmons, Nathan A.; Nicolelis, Miguel A. L.

2009-01-01

Brain–machine interfaces (BMIs) establish direct communication between the brain and artificial actuators. As such, they hold considerable promise for restoring mobility and communication in patients suffering from severe body paralysis. To achieve this end, future BMIs must also provide a means for delivering sensory signals from the actuators back to the brain. Prosthetic sensation is needed so that neuroprostheses can be better perceived and controlled. Here we show that a direct intracortical input can be added to a BMI to instruct rhesus monkeys in choosing the direction of reaching movements generated by the BMI. Somatosensory instructions were provided to two monkeys operating the BMI using either: (a) vibrotactile stimulation of the monkey's hands or (b) multi-channel intracortical microstimulation (ICMS) delivered to the primary somatosensory cortex (S1) in one monkey and posterior parietal cortex (PP) in the other. Stimulus delivery was contingent on the position of the computer cursor: the monkey placed it in the center of the screen to receive machine–brain recursive input. After 2 weeks of training, the same level of proficiency in utilizing somatosensory information was achieved with ICMS of S1 as with the stimulus delivered to the hand skin. ICMS of PP was not effective. These results indicate that direct, bi-directional communication between the brain and neuroprosthetic devices can be achieved through the combination of chronic multi-electrode recording and microstimulation of S1. We propose that in the future, bidirectional BMIs incorporating ICMS may become an effective paradigm for sensorizing neuroprosthetic devices. PMID:19750199

Decoding continuous three-dimensional hand trajectories from epidural electrocorticographic signals in Japanese macaques

NASA Astrophysics Data System (ADS)

Shimoda, Kentaro; Nagasaka, Yasuo; Chao, Zenas C.; Fujii, Naotaka

2012-06-01

Brain-machine interface (BMI) technology captures brain signals to enable control of prosthetic or communication devices with the goal of assisting patients who have limited or no ability to perform voluntary movements. Decoding of inherent information in brain signals to interpret the user's intention is one of main approaches for developing BMI technology. Subdural electrocorticography (sECoG)-based decoding provides good accuracy, but surgical complications are one of the major concerns for this approach to be applied in BMIs. In contrast, epidural electrocorticography (eECoG) is less invasive, thus it is theoretically more suitable for long-term implementation, although it is unclear whether eECoG signals carry sufficient information for decoding natural movements. We successfully decoded continuous three-dimensional hand trajectories from eECoG signals in Japanese macaques. A steady quantity of information of continuous hand movements could be acquired from the decoding system for at least several months, and a decoding model could be used for ˜10 days without significant degradation in accuracy or recalibration. The correlation coefficients between observed and predicted trajectories were lower than those for sECoG-based decoding experiments we previously reported, owing to a greater degree of chewing artifacts in eECoG-based decoding than is found in sECoG-based decoding. As one of the safest invasive recording methods available, eECoG provides an acceptable level of performance. With the ease of replacement and upgrades, eECoG systems could become the first-choice interface for real-life BMI applications.

Child abuse as a predictor of gendered sexual orientation disparities in body mass index trajectories among U.S. youth from the Growing Up Today Study.

PubMed

Katz-Wise, Sabra L; Jun, Hee-Jin; Corliss, Heather L; Jackson, Benita; Haines, Jess; Austin, S Bryn

2014-06-01

This research aimed to explain sexual orientation disparities in body mass index (BMI) by examining child abuse history, weight-related behaviors, and sociodemographics. We used data from 7,960 females and 5,992 males from the prospective Growing Up Today Study over nine waves between 1996 (ages 12-14 years) and 2007 (ages 20-25 years). Using repeated measures of BMI (kg/m(2)) as a continuous outcome, gender-stratified latent quadratic growth models adjusted for child abuse history, weight-related behaviors, and sociodemographics. BMI at age 17 years (intercept) and 1-year change in BMI (slope) are reported. Bisexual females had higher BMI at age 17 years (β = 1.59, 95% CI = 1.00-2.18) and displayed greater one-year increases in BMI (β = .09, 95% CI = .03-.14), compared with completely heterosexual females. Gay males displayed smaller 1-year increases in BMI (β = -.19, 95% CI = -.25 to -.12), compared with completely heterosexual males. No sexual orientation differences in BMI at age 17 years were observed for males, but gay males' BMI at age 25 was less than completely heterosexual males' BMI by 2 units. Among females, sexual orientation differences remained but were slightly attenuated after controlling for child abuse history, weight-related behaviors, and sociodemographics. Among males, the addition of child abuse and weight-related behaviors did not change the estimated difference in 1-year BMI increases. Sexual orientation differences in BMI were partly explained by child abuse and weight-related behaviors in females. More research is needed to explore additional drivers of these disparities among both females and males. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Neuroprosthetic limb control with electrocorticography: approaches and challenges.

PubMed

Thakor, Nitish V; Fifer, Matthew S; Hotson, Guy; Benz, Heather L; Newman, Geoffrey I; Milsap, Griffin W; Crone, Nathan E

2014-01-01

Advanced upper limb prosthetics, such as the Johns Hopkins Applied Physics Lab Modular Prosthetic Limb (MPL), are now available for research and preliminary clinical applications. Research attention has shifted to developing means of controlling these prostheses. Penetrating microelectrode arrays are often used in animal and human models to decode action potentials for cortical control. These arrays may suffer signal loss over the long-term and therefore should not be the only implant type investigated for chronic BMI use. Electrocorticographic (ECoG) signals from electrodes on the cortical surface may provide more stable long-term recordings. Several studies have demonstrated ECoG's potential for decoding cortical activity. As a result, clinical studies are investigating ECoG encoding of limb movement, as well as its use for interfacing with and controlling advanced prosthetic arms. This overview presents the technical state of the art in the use of ECoG in controlling prostheses. Technical limitations of the current approach and future directions are also presented.

Offline decoding of end-point forces using neural ensembles: application to a brain-machine interface.

PubMed

Gupta, Rahul; Ashe, James

2009-06-01

Brain-machine interfaces (BMIs) hold a lot of promise for restoring some level of motor function to patients with neuronal disease or injury. Current BMI approaches fall into two broad categories--those that decode discrete properties of limb movement (such as movement direction and movement intent) and those that decode continuous variables (such as position and velocity). However, to enable the prosthetic devices to be useful for common everyday tasks, precise control of the forces applied by the end-point of the prosthesis (e.g., the hand) is also essential. Here, we used linear regression and Kalman filter methods to show that neural activity recorded from the motor cortex of the monkey during movements in a force field can be used to decode the end-point forces applied by the subject successfully and with high fidelity. Furthermore, the models exhibit some generalization to novel task conditions. We also demonstrate how the simultaneous prediction of kinematics and kinetics can be easily achieved using the same framework, without any degradation in decoding quality. Our results represent a useful extension of the current BMI technology, making dynamic control of a prosthetic device a distinct possibility in the near future.

The Brainarium: An Interactive Immersive Tool for Brain Education, Art, and Neurotherapy

PubMed Central

2016-01-01

Recent theoretical and technological advances in neuroimaging techniques now allow brain electrical activity to be recorded using affordable and user-friendly equipment for nonscientist end-users. An increasing number of educators and artists have begun using electroencephalogram (EEG) to control multimedia and live artistic contents. In this paper, we introduce a new concept based on brain computer interface (BCI) technologies: the Brainarium. The Brainarium is a new pedagogical and artistic tool, which can deliver and illustrate scientific knowledge, as well as a new framework for scientific exploration. The Brainarium consists of a portable planetarium device that is being used as brain metaphor. This is done by projecting multimedia content on the planetarium dome and displaying EEG data recorded from a subject in real time using Brain Machine Interface (BMI) technologies. The system has been demonstrated through several performances involving an interaction between the subject controlling the BMI, a musician, and the audience during series of exhibitions and workshops in schools. We report here feedback from 134 participants who filled questionnaires to rate their experiences. Our results show improved subjective learning compared to conventional methods, improved entertainment value, improved absorption into the material being presented, and little discomfort. PMID:27698660

The Brainarium: An Interactive Immersive Tool for Brain Education, Art, and Neurotherapy.

PubMed

Grandchamp, Romain; Delorme, Arnaud

2016-01-01

Recent theoretical and technological advances in neuroimaging techniques now allow brain electrical activity to be recorded using affordable and user-friendly equipment for nonscientist end-users. An increasing number of educators and artists have begun using electroencephalogram (EEG) to control multimedia and live artistic contents. In this paper, we introduce a new concept based on brain computer interface (BCI) technologies: the Brainarium. The Brainarium is a new pedagogical and artistic tool, which can deliver and illustrate scientific knowledge, as well as a new framework for scientific exploration. The Brainarium consists of a portable planetarium device that is being used as brain metaphor. This is done by projecting multimedia content on the planetarium dome and displaying EEG data recorded from a subject in real time using Brain Machine Interface (BMI) technologies. The system has been demonstrated through several performances involving an interaction between the subject controlling the BMI, a musician, and the audience during series of exhibitions and workshops in schools. We report here feedback from 134 participants who filled questionnaires to rate their experiences. Our results show improved subjective learning compared to conventional methods, improved entertainment value, improved absorption into the material being presented, and little discomfort.

Brain-Machine Interface control of a robot arm using actor-critic rainforcement learning.

PubMed

Pohlmeyer, Eric A; Mahmoudi, Babak; Geng, Shijia; Prins, Noeline; Sanchez, Justin C

2012-01-01

Here we demonstrate how a marmoset monkey can use a reinforcement learning (RL) Brain-Machine Interface (BMI) to effectively control the movements of a robot arm for a reaching task. In this work, an actor-critic RL algorithm used neural ensemble activity in the monkey's motor cortext to control the robot movements during a two-target decision task. This novel approach to decoding offers unique advantages for BMI control applications. Compared to supervised learning decoding methods, the actor-critic RL algorithm does not require an explicit set of training data to create a static control model, but rather it incrementally adapts the model parameters according to its current performance, in this case requiring only a very basic feedback signal. We show how this algorithm achieved high performance when mapping the monkey's neural states (94%) to robot actions, and only needed to experience a few trials before obtaining accurate real-time control of the robot arm. Since RL methods responsively adapt and adjust their parameters, they can provide a method to create BMIs that are robust against perturbations caused by changes in either the neural input space or the output actions they generate under different task requirements or goals.

Advances in neuroprosthetic learning and control.

PubMed

Carmena, Jose M

2013-01-01

Significant progress has occurred in the field of brain-machine interfaces (BMI) since the first demonstrations with rodents, monkeys, and humans controlling different prosthetic devices directly with neural activity. This technology holds great potential to aid large numbers of people with neurological disorders. However, despite this initial enthusiasm and the plethora of available robotic technologies, existing neural interfaces cannot as yet master the control of prosthetic, paralyzed, or otherwise disabled limbs. Here I briefly discuss recent advances from our laboratory into the neural basis of BMIs that should lead to better prosthetic control and clinically viable solutions, as well as new insights into the neurobiology of action.

Advances in Neuroprosthetic Learning and Control

PubMed Central

Carmena, Jose M.

2013-01-01

Significant progress has occurred in the field of brain–machine interfaces (BMI) since the first demonstrations with rodents, monkeys, and humans controlling different prosthetic devices directly with neural activity. This technology holds great potential to aid large numbers of people with neurological disorders. However, despite this initial enthusiasm and the plethora of available robotic technologies, existing neural interfaces cannot as yet master the control of prosthetic, paralyzed, or otherwise disabled limbs. Here I briefly discuss recent advances from our laboratory into the neural basis of BMIs that should lead to better prosthetic control and clinically viable solutions, as well as new insights into the neurobiology of action. PMID:23700383

Excess BMI in Childhood: A Modifiable Risk Factor for Type 1 Diabetes Development?

PubMed Central

Liu, Yuk-Fun; Evans-Molina, Carmella; Libman, Ingrid M.; Besser, Rachel; Becker, Dorothy J.; Rodriguez, Henry; Moran, Antoinette; Gitelman, Stephen E.; Redondo, Maria J.

2017-01-01

OBJECTIVE We aimed to determine the effect of elevated BMI over time on the progression to type 1 diabetes in youth. RESEARCH DESIGN AND METHODS We studied 1,117 children in the TrialNet Pathway to Prevention cohort (autoantibody-positive relatives of patients with type 1 diabetes). Longitudinally accumulated BMI above the 85th age- and sex-adjusted percentile generated a cumulative excess BMI (ceBMI) index. Recursive partitioning and multivariate analyses yielded sex- and age-specific ceBMI thresholds for greatest type 1 diabetes risk. RESULTS Higher ceBMI conferred significantly greater risk of progressing to type 1 diabetes. The increased diabetes risk occurred at lower ceBMI values in children <12 years of age compared with older subjects and in females versus males. CONCLUSIONS Elevated BMI is associated with increased risk of diabetes progression in pediatric autoantibody-positive relatives, but the effect varies by sex and age. PMID:28202550

Control of an Ambulatory Exoskeleton with a Brain-Machine Interface for Spinal Cord Injury Gait Rehabilitation.

PubMed

López-Larraz, Eduardo; Trincado-Alonso, Fernando; Rajasekaran, Vijaykumar; Pérez-Nombela, Soraya; Del-Ama, Antonio J; Aranda, Joan; Minguez, Javier; Gil-Agudo, Angel; Montesano, Luis

2016-01-01

The closed-loop control of rehabilitative technologies by neural commands has shown a great potential to improve motor recovery in patients suffering from paralysis. Brain-machine interfaces (BMI) can be used as a natural control method for such technologies. BMI provides a continuous association between the brain activity and peripheral stimulation, with the potential to induce plastic changes in the nervous system. Paraplegic patients, and especially the ones with incomplete injuries, constitute a potential target population to be rehabilitated with brain-controlled robotic systems, as they may improve their gait function after the reinforcement of their spared intact neural pathways. This paper proposes a closed-loop BMI system to control an ambulatory exoskeleton-without any weight or balance support-for gait rehabilitation of incomplete spinal cord injury (SCI) patients. The integrated system was validated with three healthy subjects, and its viability in a clinical scenario was tested with four SCI patients. Using a cue-guided paradigm, the electroencephalographic signals of the subjects were used to decode their gait intention and to trigger the movements of the exoskeleton. We designed a protocol with a special emphasis on safety, as patients with poor balance were required to stand and walk. We continuously monitored their fatigue and exertion level, and conducted usability and user-satisfaction tests after the experiments. The results show that, for the three healthy subjects, 84.44 ± 14.56% of the trials were correctly decoded. Three out of four patients performed at least one successful BMI session, with an average performance of 77.6 1 ± 14.72%. The shared control strategy implemented (i.e., the exoskeleton could only move during specific periods of time) was effective in preventing unexpected movements during periods in which patients were asked to relax. On average, 55.22 ± 16.69% and 40.45 ± 16.98% of the trials (for healthy subjects and patients, respectively) would have suffered from unexpected activations (i.e., false positives) without the proposed control strategy. All the patients showed low exertion and fatigue levels during the performance of the experiments. This paper constitutes a proof-of-concept study to validate the feasibility of a BMI to control an ambulatory exoskeleton by patients with incomplete paraplegia (i.e., patients with good prognosis for gait rehabilitation).

Control of an Ambulatory Exoskeleton with a Brain–Machine Interface for Spinal Cord Injury Gait Rehabilitation

PubMed Central

López-Larraz, Eduardo; Trincado-Alonso, Fernando; Rajasekaran, Vijaykumar; Pérez-Nombela, Soraya; del-Ama, Antonio J.; Aranda, Joan; Minguez, Javier; Gil-Agudo, Angel; Montesano, Luis

2016-01-01

The closed-loop control of rehabilitative technologies by neural commands has shown a great potential to improve motor recovery in patients suffering from paralysis. Brain–machine interfaces (BMI) can be used as a natural control method for such technologies. BMI provides a continuous association between the brain activity and peripheral stimulation, with the potential to induce plastic changes in the nervous system. Paraplegic patients, and especially the ones with incomplete injuries, constitute a potential target population to be rehabilitated with brain-controlled robotic systems, as they may improve their gait function after the reinforcement of their spared intact neural pathways. This paper proposes a closed-loop BMI system to control an ambulatory exoskeleton—without any weight or balance support—for gait rehabilitation of incomplete spinal cord injury (SCI) patients. The integrated system was validated with three healthy subjects, and its viability in a clinical scenario was tested with four SCI patients. Using a cue-guided paradigm, the electroencephalographic signals of the subjects were used to decode their gait intention and to trigger the movements of the exoskeleton. We designed a protocol with a special emphasis on safety, as patients with poor balance were required to stand and walk. We continuously monitored their fatigue and exertion level, and conducted usability and user-satisfaction tests after the experiments. The results show that, for the three healthy subjects, 84.44 ± 14.56% of the trials were correctly decoded. Three out of four patients performed at least one successful BMI session, with an average performance of 77.6 1 ± 14.72%. The shared control strategy implemented (i.e., the exoskeleton could only move during specific periods of time) was effective in preventing unexpected movements during periods in which patients were asked to relax. On average, 55.22 ± 16.69% and 40.45 ± 16.98% of the trials (for healthy subjects and patients, respectively) would have suffered from unexpected activations (i.e., false positives) without the proposed control strategy. All the patients showed low exertion and fatigue levels during the performance of the experiments. This paper constitutes a proof-of-concept study to validate the feasibility of a BMI to control an ambulatory exoskeleton by patients with incomplete paraplegia (i.e., patients with good prognosis for gait rehabilitation). PMID:27536214

Decoding of top-down cognitive processing for SSVEP-controlled BMI

PubMed Central

Min, Byoung-Kyong; Dähne, Sven; Ahn, Min-Hee; Noh, Yung-Kyun; Müller, Klaus-Robert

2016-01-01

We present a fast and accurate non-invasive brain-machine interface (BMI) based on demodulating steady-state visual evoked potentials (SSVEPs) in electroencephalography (EEG). Our study reports an SSVEP-BMI that, for the first time, decodes primarily based on top-down and not bottom-up visual information processing. The experimental setup presents a grid-shaped flickering line array that the participants observe while intentionally attending to a subset of flickering lines representing the shape of a letter. While the flickering pixels stimulate the participant’s visual cortex uniformly with equal probability, the participant’s intention groups the strokes and thus perceives a ‘letter Gestalt’. We observed decoding accuracy of 35.81% (up to 65.83%) with a regularized linear discriminant analysis; on average 2.05-fold, and up to 3.77-fold greater than chance levels in multi-class classification. Compared to the EEG signals, an electrooculogram (EOG) did not significantly contribute to decoding accuracies. Further analysis reveals that the top-down SSVEP paradigm shows the most focalised activation pattern around occipital visual areas; Granger causality analysis consistently revealed prefrontal top-down control over early visual processing. Taken together, the present paradigm provides the first neurophysiological evidence for the top-down SSVEP BMI paradigm, which potentially enables multi-class intentional control of EEG-BMIs without using gaze-shifting. PMID:27808125

Decoding of top-down cognitive processing for SSVEP-controlled BMI

NASA Astrophysics Data System (ADS)

Min, Byoung-Kyong; Dähne, Sven; Ahn, Min-Hee; Noh, Yung-Kyun; Müller, Klaus-Robert

2016-11-01

We present a fast and accurate non-invasive brain-machine interface (BMI) based on demodulating steady-state visual evoked potentials (SSVEPs) in electroencephalography (EEG). Our study reports an SSVEP-BMI that, for the first time, decodes primarily based on top-down and not bottom-up visual information processing. The experimental setup presents a grid-shaped flickering line array that the participants observe while intentionally attending to a subset of flickering lines representing the shape of a letter. While the flickering pixels stimulate the participant’s visual cortex uniformly with equal probability, the participant’s intention groups the strokes and thus perceives a ‘letter Gestalt’. We observed decoding accuracy of 35.81% (up to 65.83%) with a regularized linear discriminant analysis; on average 2.05-fold, and up to 3.77-fold greater than chance levels in multi-class classification. Compared to the EEG signals, an electrooculogram (EOG) did not significantly contribute to decoding accuracies. Further analysis reveals that the top-down SSVEP paradigm shows the most focalised activation pattern around occipital visual areas; Granger causality analysis consistently revealed prefrontal top-down control over early visual processing. Taken together, the present paradigm provides the first neurophysiological evidence for the top-down SSVEP BMI paradigm, which potentially enables multi-class intentional control of EEG-BMIs without using gaze-shifting.

Quantifying the Role of Circulating Unconjugated Estradiol in Mediating the Body Mass Index-Breast Cancer Association.

PubMed

Schairer, Catherine; Fuhrman, Barbara J; Boyd-Morin, Jennifer; Genkinger, Jeanine M; Gail, Mitchell H; Hoover, Robert N; Ziegler, Regina G

2016-01-01

Higher body mass index (BMI) and circulating estrogen levels each increase postmenopausal breast cancer risk, particularly estrogen receptor-positive (ER(+)) tumors. Higher BMI also increases estrogen production. We estimated the proportion of the BMI-ER(+) breast cancer association mediated through estrogen in a case-control study nested within the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Participants included 143 women with invasive ER(+) breast cancer and 268 matched controls, all postmenopausal and never having used hormone therapy at baseline. We used liquid chromatography-tandem mass spectrometry to measure 15 estrogens and estrogen metabolites in baseline serum. We calculated BMI from self-reported height and weight at baseline. We estimated the mediating effect of unconjugated estradiol on the BMI-ER(+) breast cancer association using Aalen additive hazards and Cox regression models. All estrogens and estrogen metabolites were statistically significantly correlated with BMI, with unconjugated estradiol most strongly correlated [Pearson correlation (r) = 0.45]. Approximately 7% to 10% of the effect of overweight, 12% to 15% of the effect of obesity, and 19% to 20% of the effect of a 5 kg/m(2) BMI increase on ER(+) breast cancer risk was mediated through unconjugated estradiol. The BMI-breast cancer association, once adjusted for unconjugated estradiol, was not modified by further adjustment for two metabolic ratios statistically significantly associated with both breast cancer and BMI. Circulating unconjugated estradiol levels partially mediate the BMI-breast cancer association, but other potentially important estrogen mediators (e.g., bioavailable estradiol) were not evaluated. Further research is required to identify mechanisms underlying the BMI-breast cancer association. ©2015 American Association for Cancer Research.

Obesity-Related Metabolic Risk in Sedentary Hispanic Adolescent Girls with Normal BMI.

PubMed

van der Heijden, Gert-Jan; Wang, Zhiyue J; Chu, Zili D; Haymond, Morey; Sauer, Pieter J J; Sunehag, Agneta L

2018-06-15

Hispanic adolescent girls with normal BMI frequently have high body fat %. Without knowledge of body fat content and distribution, their risk for metabolic complications is unknown. We measured metabolic risk indicators and abdominal fat distribution in post-pubertal Hispanic adolescent girls with Normal BMI (N-BMI: BMI < 85th percentile) and compared these indicators between girls with Normal BMI and High Fat content (N-BMI-HF: body fat ≥ 27%; n = 15) and Normal BMI and Normal Fat content (N-BMI-NF: body fat < 27%; n = 8). Plasma concentrations of glucose, insulin, adiponectin, leptin and Hs-CRP were determined. Insulin resistance was calculated using an oral glucose tolerance test. Body fat % was measured by DXA and subcutaneous, visceral and hepatic fat by MRI/MRS. The N-BMI-HF girls had increased abdominal and hepatic fat content and increased insulin resistance, plasma leptin and Hs-CRP concentrations ( p < 0.05) as compared to their N-BMI-NF counterparts. In N-BMI girls, insulin resistance, plasma insulin and leptin correlated with BMI and body fat % ( p < 0.05). This research confirms the necessity of the development of BMI and body fat % cut-off criteria per sex, age and racial/ethnic group based on metabolic risk factors to optimize the effectiveness of metabolic risk screening procedures.

Toward a whole-body neuroprosthetic.

PubMed

Lebedev, Mikhail A; Nicolelis, Miguel A L

2011-01-01

Brain-machine interfaces (BMIs) hold promise for the restoration of body mobility in patients suffering from devastating motor deficits caused by brain injury, neurological diseases, and limb loss. Considerable progress has been achieved in BMIs that enact arm movements, and initial work has been done on BMIs for lower limb and trunk control. These developments put Duke University Center for Neuroengineering in the position to develop the first BMI for whole-body control. This whole-body BMI will incorporate very large-scale brain recordings, advanced decoding algorithms, artificial sensory feedback based on electrical stimulation of somatosensory areas, virtual environment representations, and a whole-body exoskeleton. This system will be first tested in nonhuman primates and then transferred to clinical trials in humans. Copyright © 2011 Elsevier B.V. All rights reserved.

Reversible large-scale modification of cortical networks during neuroprosthetic control.

PubMed

Ganguly, Karunesh; Dimitrov, Dragan F; Wallis, Jonathan D; Carmena, Jose M

2011-05-01

Brain-machine interfaces (BMIs) provide a framework for studying cortical dynamics and the neural correlates of learning. Neuroprosthetic control has been associated with tuning changes in specific neurons directly projecting to the BMI (hereafter referred to as direct neurons). However, little is known about the larger network dynamics. By monitoring ensembles of neurons that were either causally linked to BMI control or indirectly involved, we found that proficient neuroprosthetic control is associated with large-scale modifications to the cortical network in macaque monkeys. Specifically, there were changes in the preferred direction of both direct and indirect neurons. Notably, with learning, there was a relative decrease in the net modulation of indirect neural activity in comparison with direct activity. These widespread differential changes in the direct and indirect population activity were markedly stable from one day to the next and readily coexisted with the long-standing cortical network for upper limb control. Thus, the process of learning BMI control is associated with differential modification of neural populations based on their specific relation to movement control.

Regional Differences as Barriers to Body Mass Index Screening Described by Ohio School Nurses

ERIC Educational Resources Information Center

Stalter, Ann M.; Chaudry, Rosemary V.; Polivka, Barbara J.

2011-01-01

Background: Body mass index (BMI) screening is advocated by the National Association of School Nurses (NASN). Research identifying barriers to BMI screening in public elementary school settings has been sparse. The purpose of the study was to identify barriers and facilitating factors of BMI screening practices among Ohio school nurses working in…

Parent/Student Risk and Protective Factors in Understanding Early Adolescent's Body Mass Index

ERIC Educational Resources Information Center

Fitzpatrick, Kevin M.; Willis, Don

2016-01-01

This article's aim is to examine correlates of middle school students' body mass index (BMI). Little research simultaneously has considered both child and parent correlates in predicting child's BMI; we examine the interrelationships between middle school students and their parent's risks and protective factors and their impact on the child's BMI.…

Relationships between Illicit Drug Use and Body Mass Index among Adolescents

ERIC Educational Resources Information Center

Blackstone, Sarah R.; Herrmann, Lynn K.

2016-01-01

Prior research has established associations between body mass index (BMI) and use of alcohol, tobacco, and marijuana. However, little research has been done investigating the relationship between other common illicit drugs and BMI trends. The present study investigated whether adolescents who reported using illicit drugs showed differences in BMI…

Decoding the non-stationary neuron spike trains by dual Monte Carlo point process estimation in motor Brain Machine Interfaces.

PubMed

Liao, Yuxi; Li, Hongbao; Zhang, Qiaosheng; Fan, Gong; Wang, Yiwen; Zheng, Xiaoxiang

2014-01-01

Decoding algorithm in motor Brain Machine Interfaces translates the neural signals to movement parameters. They usually assume the connection between the neural firings and movements to be stationary, which is not true according to the recent studies that observe the time-varying neuron tuning property. This property results from the neural plasticity and motor learning etc., which leads to the degeneration of the decoding performance when the model is fixed. To track the non-stationary neuron tuning during decoding, we propose a dual model approach based on Monte Carlo point process filtering method that enables the estimation also on the dynamic tuning parameters. When applied on both simulated neural signal and in vivo BMI data, the proposed adaptive method performs better than the one with static tuning parameters, which raises a promising way to design a long-term-performing model for Brain Machine Interfaces decoder.

Feasibility study for future implantable neural-silicon interface devices.

PubMed

Al-Armaghany, Allann; Yu, Bo; Mak, Terrence; Tong, Kin-Fai; Sun, Yihe

2011-01-01

The emerging neural-silicon interface devices bridge nerve systems with artificial systems and play a key role in neuro-prostheses and neuro-rehabilitation applications. Integrating neural signal collection, processing and transmission on a single device will make clinical applications more practical and feasible. This paper focuses on the wireless antenna part and real-time neural signal analysis part of implantable brain-machine interface (BMI) devices. We propose to use millimeter-wave for wireless connections between different areas of a brain. Various antenna, including microstrip patch, monopole antenna and substrate integrated waveguide antenna are considered for the intra-cortical proximity communication. A Hebbian eigenfilter based method is proposed for multi-channel neuronal spike sorting. Folding and parallel design techniques are employed to explore various structures and make a trade-off between area and power consumption. Field programmable logic arrays (FPGAs) are used to evaluate various structures.

Neural Control of a Tracking Task via Attention-Gated Reinforcement Learning for Brain-Machine Interfaces.

PubMed

Wang, Yiwen; Wang, Fang; Xu, Kai; Zhang, Qiaosheng; Zhang, Shaomin; Zheng, Xiaoxiang

2015-05-01

Reinforcement learning (RL)-based brain machine interfaces (BMIs) enable the user to learn from the environment through interactions to complete the task without desired signals, which is promising for clinical applications. Previous studies exploited Q-learning techniques to discriminate neural states into simple directional actions providing the trial initial timing. However, the movements in BMI applications can be quite complicated, and the action timing explicitly shows the intention when to move. The rich actions and the corresponding neural states form a large state-action space, imposing generalization difficulty on Q-learning. In this paper, we propose to adopt attention-gated reinforcement learning (AGREL) as a new learning scheme for BMIs to adaptively decode high-dimensional neural activities into seven distinct movements (directional moves, holdings and resting) due to the efficient weight-updating. We apply AGREL on neural data recorded from M1 of a monkey to directly predict a seven-action set in a time sequence to reconstruct the trajectory of a center-out task. Compared to Q-learning techniques, AGREL could improve the target acquisition rate to 90.16% in average with faster convergence and more stability to follow neural activity over multiple days, indicating the potential to achieve better online decoding performance for more complicated BMI tasks.

Virtual reality hardware and graphic display options for brain-machine interfaces

PubMed Central

Marathe, Amar R.; Carey, Holle L.; Taylor, Dawn M.

2009-01-01

Virtual reality hardware and graphic displays are reviewed here as a development environment for brain-machine interfaces (BMIs). Two desktop stereoscopic monitors and one 2D monitor were compared in a visual depth discrimination task and in a 3D target-matching task where able-bodied individuals used actual hand movements to match a virtual hand to different target hands. Three graphic representations of the hand were compared: a plain sphere, a sphere attached to the fingertip of a realistic hand and arm, and a stylized pacman-like hand. Several subjects had great difficulty using either stereo monitor for depth perception when perspective size cues were removed. A mismatch in stereo and size cues generated inappropriate depth illusions. This phenomenon has implications for choosing target and virtual hand sizes in BMI experiments. Target matching accuracy was about as good with the 2D monitor as with either 3D monitor. However, users achieved this accuracy by exploring the boundaries of the hand in the target with carefully controlled movements. This method of determining relative depth may not be possible in BMI experiments if movement control is more limited. Intuitive depth cues, such as including a virtual arm, can significantly improve depth perception accuracy with or without stereo viewing. PMID:18006069

Wireless Cortical Brain-Machine Interface for Whole-Body Navigation in Primates

NASA Astrophysics Data System (ADS)

Rajangam, Sankaranarayani; Tseng, Po-He; Yin, Allen; Lehew, Gary; Schwarz, David; Lebedev, Mikhail A.; Nicolelis, Miguel A. L.

2016-03-01

Several groups have developed brain-machine-interfaces (BMIs) that allow primates to use cortical activity to control artificial limbs. Yet, it remains unknown whether cortical ensembles could represent the kinematics of whole-body navigation and be used to operate a BMI that moves a wheelchair continuously in space. Here we show that rhesus monkeys can learn to navigate a robotic wheelchair, using their cortical activity as the main control signal. Two monkeys were chronically implanted with multichannel microelectrode arrays that allowed wireless recordings from ensembles of premotor and sensorimotor cortical neurons. Initially, while monkeys remained seated in the robotic wheelchair, passive navigation was employed to train a linear decoder to extract 2D wheelchair kinematics from cortical activity. Next, monkeys employed the wireless BMI to translate their cortical activity into the robotic wheelchair’s translational and rotational velocities. Over time, monkeys improved their ability to navigate the wheelchair toward the location of a grape reward. The navigation was enacted by populations of cortical neurons tuned to whole-body displacement. During practice with the apparatus, we also noticed the presence of a cortical representation of the distance to reward location. These results demonstrate that intracranial BMIs could restore whole-body mobility to severely paralyzed patients in the future.

Unscented Kalman Filter for Brain-Machine Interfaces

PubMed Central

Li, Zheng; O'Doherty, Joseph E.; Hanson, Timothy L.; Lebedev, Mikhail A.; Henriquez, Craig S.; Nicolelis, Miguel A. L.

2009-01-01

Brain machine interfaces (BMIs) are devices that convert neural signals into commands to directly control artificial actuators, such as limb prostheses. Previous real-time methods applied to decoding behavioral commands from the activity of populations of neurons have generally relied upon linear models of neural tuning and were limited in the way they used the abundant statistical information contained in the movement profiles of motor tasks. Here, we propose an n-th order unscented Kalman filter which implements two key features: (1) use of a non-linear (quadratic) model of neural tuning which describes neural activity significantly better than commonly-used linear tuning models, and (2) augmentation of the movement state variables with a history of n-1 recent states, which improves prediction of the desired command even before incorporating neural activity information and allows the tuning model to capture relationships between neural activity and movement at multiple time offsets simultaneously. This new filter was tested in BMI experiments in which rhesus monkeys used their cortical activity, recorded through chronically implanted multielectrode arrays, to directly control computer cursors. The 10th order unscented Kalman filter outperformed the standard Kalman filter and the Wiener filter in both off-line reconstruction of movement trajectories and real-time, closed-loop BMI operation. PMID:19603074

Trajectories of BMI from early childhood through early adolescence: SES and psychosocial predictors.

PubMed

Lane, Sean P; Bluestone, Cheryl; Burke, Christopher T

2013-02-01

This study examined the ways in which body mass index (BMI) percentile - an identified risk factor for overweight and cardiovascular disease in adulthood - develops from birth through early adolescence. In addition, we examined whether psychosocial factors, such as parenting style and maternal depression, mediated the link between socio-economic status (SES) and BMI growth. Design. Data were obtained from phases 1-3 of the National Institute of Child Health and Human Development (NICHD) Study of Early Child Care and Youth Development (SECCYD) - a longitudinal study that followed children from 10 communities in the United States from birth to age 11. We applied growth mixture models to identify distinct subtypes of BMI development. Within these models, we performed between- and within-class mediation analyses to examine whether SES predicted class membership or differences in development within each class via maternal depression and parenting styles. Results identified three prototypic trajectories of BMI percentile growth, elevated, steady increase, and stable. We found evidence for both between- and within-class mediation, suggesting multiple pathways by which SES can affect BMI development. These findings add to the research that suggests that being in a family with a low SES is associated with falling into patterns of development characterized by early and lasting increases in BMI relative to one's peers, and that this association is partly accounted for by maternal depression and parenting styles. What is already known? Past research has found evidence that patterns of childhood overweight are impacted by socioeconomic status through psychosocial factors like parenting and depression. This evidence is often limited to individual points in time where neglectful, permissive, and authoritarian parenting and higher levels of maternal depression are associated with higher levels of overweight status among children from infancy to adolescence. However, little research has linked together whether the children who receive non-authoritative parenting and are overweight in infancy are the same children who are overweight in adolescence. WHAT DOES THIS STUDY ADD?: • Evidence for 3 different prototypes of BMI percentile growth over the course of childhood approaching adolescence. • Adds complexity re the influence of parenting styles as an influence on patterns of weight gain. • Buttresses existing research as to early and lasting effects of SES on patterns of BMI. © 2012 The British Psychological Society.

The Interplay among BMI z-Score, Peer Victmization, and Self-Concept in Outpatient Children and Adolescents with Overweight or Obesity.

PubMed

Bacchini, Dario; Licenziati, Maria Rosaria; Affuso, Gaetana; Garrasi, Alessandra; Corciulo, Nicola; Driul, Daniela; Tanas, Rita; Fiumani, Perla Maria; Di Pietro, Elena; Pesce, Sabino; Crinò, Antonino; Maltoni, Giulio; Iughetti, Lorenzo; Sartorio, Alessandro; Deiana, Manuela; Lombardi, Francesca; Valerio, Giuliana

2017-06-01

Research has provided evidence that obesity is associated with peer victimization and low levels of self-concept. No study has examined the relationship between BMI z-score, self-concept in multiple domains, and peer victimization. The aim of the research was to investigate the interplay between BMI z-score, self-concept in multiple domains (physical, athletic, social), and peer victimization, testing direct, mediated, and moderated associations. Eighty hundred fifteen outpatient children and adolescents were consecutively recruited in 14 hospitals distributed over the Italian country. The sample consisted of 419 males and 396 females; mean age 10.91 ± 1.97 years (range 6-14 years) and mean BMI z-score 1.85 ± 0.74 (range -0.97 ± 3.27). Peer victimization and self-concept were assessed with a revised Olweus Bully/Victim Questionnaire and with the Self-Perception Profile for Children. A structural equation model approach was used to determine the associations among variables, testing two competing models. In both models, path analysis revealed that BMI z-score was directly associated with peer victimization and self-concept in multiple domains. In the first model, peer victimization mediated the relationship between BMI-score and self-concept, whereas in the alternative model, self-concept mediated the relationship between BMI z-score and peer victimization. Interaction analyses revealed that social competence moderated the relationship between BMI z-score and peer victimization and that peer victimization moderated the relationship between BMI z-score and physical appearance. Higher levels of BMI z-score are a risk factor for peer victimization and poor self-concept. When high levels of BMI z-score are associated with a negative self-concept, the risk of victimization increases. Preventive and supportive interventions are needed to avoid negative consequences on quality of life in children and adolescents with obesity.

State-Dependent Decoding Algorithms Improve the Performance of a Bidirectional BMI in Anesthetized Rats.

PubMed

De Feo, Vito; Boi, Fabio; Safaai, Houman; Onken, Arno; Panzeri, Stefano; Vato, Alessandro

2017-01-01

Brain-machine interfaces (BMIs) promise to improve the quality of life of patients suffering from sensory and motor disabilities by creating a direct communication channel between the brain and the external world. Yet, their performance is currently limited by the relatively small amount of information that can be decoded from neural activity recorded form the brain. We have recently proposed that such decoding performance may be improved when using state-dependent decoding algorithms that predict and discount the large component of the trial-to-trial variability of neural activity which is due to the dependence of neural responses on the network's current internal state. Here we tested this idea by using a bidirectional BMI to investigate the gain in performance arising from using a state-dependent decoding algorithm. This BMI, implemented in anesthetized rats, controlled the movement of a dynamical system using neural activity decoded from motor cortex and fed back to the brain the dynamical system's position by electrically microstimulating somatosensory cortex. We found that using state-dependent algorithms that tracked the dynamics of ongoing activity led to an increase in the amount of information extracted form neural activity by 22%, with a consequently increase in all of the indices measuring the BMI's performance in controlling the dynamical system. This suggests that state-dependent decoding algorithms may be used to enhance BMIs at moderate computational cost.

Neuron selection based on deflection coefficient maximization for the neural decoding of dexterous finger movements.

PubMed

Kim, Yong-Hee; Thakor, Nitish V; Schieber, Marc H; Kim, Hyoung-Nam

2015-05-01

Future generations of brain-machine interface (BMI) will require more dexterous motion control such as hand and finger movements. Since a population of neurons in the primary motor cortex (M1) area is correlated with finger movements, neural activities recorded in M1 area are used to reconstruct an intended finger movement. In a BMI system, decoding discrete finger movements from a large number of input neurons does not guarantee a higher decoding accuracy in spite of the increase in computational burden. Hence, we hypothesize that selecting neurons important for coding dexterous flexion/extension of finger movements would improve the BMI performance. In this paper, two metrics are presented to quantitatively measure the importance of each neuron based on Bayes risk minimization and deflection coefficient maximization in a statistical decision problem. Since motor cortical neurons are active with movements of several different fingers, the proposed method is more suitable for a discrete decoding of flexion-extension finger movements than the previous methods for decoding reaching movements. In particular, the proposed metrics yielded high decoding accuracies across all subjects and also in the case of including six combined two-finger movements. While our data acquisition and analysis was done off-line and post processing, our results point to the significance of highly coding neurons in improving BMI performance.

Neuron Selection Based on Deflection Coefficient Maximization for the Neural Decoding of Dexterous Finger Movements

PubMed Central

Kim, Yong-Hee; Thakor, Nitish V.; Schieber, Marc H.; Kim, Hyoung-Nam

2015-01-01

Future generations of brain-machine interface (BMI) will require more dexterous motion control such as hand and finger movements. Since a population of neurons in the primary motor cortex (M1) area is correlated with finger movements, neural activities recorded in M1 area are used to reconstruct an intended finger movement. In a BMI system, decoding discrete finger movements from a large number of input neurons does not guarantee a higher decoding accuracy in spite of the increase in computational burden. Hence, we hypothesize that selecting neurons important for coding dexterous flexion/extension of finger movements would improve the BMI performance. In this paper, two metrics are presented to quantitatively measure the importance of each neuron based on Bayes risk minimization and deflection coefficient maximization in a statistical decision problem. Since motor cortical neurons are active with movements of several different fingers, the proposed method is more suitable for a discrete decoding of flexion-extension finger movements than the previous methods for decoding reaching movements. In particular, the proposed metrics yielded high decoding accuracies across all subjects and also in the case of including six combined two-finger movements. While our data acquisition and analysis was done off-line and post processing, our results point to the significance of highly coding neurons in improving BMI performance. PMID:25347884

[PVFS 2000: An operational parallel file system for Beowulf

NASA Technical Reports Server (NTRS)

Ligon, Walt

2004-01-01

The approach has been to develop Parallel Virtual File System version 2 (PVFS2) , retaining the basic philosophy of the original file system but completely rewriting the code. It shows the architecture of the server and client components. BMI - BMI is the network abstraction layer. It is designed with a common driver and modules for each protocol supported. The interface is non-blocking, and provides mechanisms for optimizations including pinning user buffers. Currently TCP/IP and GM(Myrinet) modules have been implemented. Trove -Trove is the storage abstraction layer. It provides for storing both data spaces and name/value pairs. Trove can also be implemented using different underlying storage mechanisms including native files, raw disk partitions, SQL and other databases. The current implementation uses native files for data spaces and Berkeley db for name/value pairs.

Body weight and risk of soft-tissue sarcoma

PubMed Central

Tavani, A; Soler, M; Vecchia, C La; Negri, E; Gallus, S; Franceschi, S

1999-01-01

The relation between body mass (BMI) and soft-tissue sarcoma (STS) risk was evaluated in a case–control study from Northern Italy based on 217 incident STS and 1297 hospital controls. The risk of STS rose with BMI, with multivariate odds ratios of 3.49 (95% confidence interval (CI) 1.06–11.55) among men and 3.26 (95% CI 1.27–8.35) among women with a BMI >30 kg m–2 compared to those with BMI ≤ 20 kg m–2. © 1999 Cancer Research Campaign PMID:10555763

Associations between Food Outlets around Schools and BMI among Primary Students in England: A Cross-Classified Multi-Level Analysis.

PubMed

Williams, Julianne; Scarborough, Peter; Townsend, Nick; Matthews, Anne; Burgoine, Thomas; Mumtaz, Lorraine; Rayner, Mike

2015-01-01

Researchers and policy-makers are interested in the influence that food retailing around schools may have on child obesity risk. Most previous research comes from North America, uses data aggregated at the school-level and focuses on associations between fast food outlets and school obesity rates. This study examines associations between food retailing and BMI among a large sample of primary school students in Berkshire, England. By controlling for individual, school and home characteristics and stratifying results across the primary school years, we aimed to identify if the food environment around schools had an effect on BMI, independent of socio-economic variables. We measured the densities of fast food outlets and food stores found within schoolchildren's home and school environments using Geographic Information Systems (GIS) and data from local councils. We linked these data to measures from the 2010/11 National Child Measurement Programme and used a cross-classified multi-level approach to examine associations between food retailing and BMI z-scores. Analyses were stratified among Reception (aged 4-5) and Year 6 (aged 10-11) students to measure associations across the primary school years. Our multilevel model had three levels to account for individual (n = 16,956), home neighbourhood (n = 664) and school (n = 268) factors. After controlling for confounders, there were no significant associations between retailing near schools and student BMI, but significant positive associations between fast food outlets in home neighbourhood and BMI z-scores. Year 6 students living in areas with the highest density of fast food outlets had an average BMI z-score that was 0.12 (95% CI: 0.04, 0.20) higher than those living in areas with none. We found little evidence to suggest that food retailing around schools influences student BMI. There is some evidence to suggest that fast food outlet densities in a child's home neighbourhood may have an effect on BMI, particularly among girls, but more research is needed to inform effective policies targeting the effects of the retail environment on child obesity.

Associations between Food Outlets around Schools and BMI among Primary Students in England: A Cross-Classified Multi-Level Analysis

PubMed Central

Williams, Julianne; Scarborough, Peter; Townsend, Nick; Matthews, Anne; Burgoine, Thomas; Mumtaz, Lorraine; Rayner, Mike

2015-01-01

Introduction Researchers and policy-makers are interested in the influence that food retailing around schools may have on child obesity risk. Most previous research comes from North America, uses data aggregated at the school-level and focuses on associations between fast food outlets and school obesity rates. This study examines associations between food retailing and BMI among a large sample of primary school students in Berkshire, England. By controlling for individual, school and home characteristics and stratifying results across the primary school years, we aimed to identify if the food environment around schools had an effect on BMI, independent of socio-economic variables. Methods We measured the densities of fast food outlets and food stores found within schoolchildren’s home and school environments using Geographic Information Systems (GIS) and data from local councils. We linked these data to measures from the 2010/11 National Child Measurement Programme and used a cross-classified multi-level approach to examine associations between food retailing and BMI z-scores. Analyses were stratified among Reception (aged 4-5) and Year 6 (aged 10-11) students to measure associations across the primary school years. Results Our multilevel model had three levels to account for individual (n = 16,956), home neighbourhood (n = 664) and school (n = 268) factors. After controlling for confounders, there were no significant associations between retailing near schools and student BMI, but significant positive associations between fast food outlets in home neighbourhood and BMI z-scores. Year 6 students living in areas with the highest density of fast food outlets had an average BMI z-score that was 0.12 (95% CI: 0.04, 0.20) higher than those living in areas with none. Discussion We found little evidence to suggest that food retailing around schools influences student BMI. There is some evidence to suggest that fast food outlet densities in a child’s home neighbourhood may have an effect on BMI, particularly among girls, but more research is needed to inform effective policies targeting the effects of the retail environment on child obesity. PMID:26186610

Minimizing data transfer with sustained performance in wireless brain-machine interfaces

NASA Astrophysics Data System (ADS)

Thor Thorbergsson, Palmi; Garwicz, Martin; Schouenborg, Jens; Johansson, Anders J.

2012-06-01

Brain-machine interfaces (BMIs) may be used to investigate neural mechanisms or to treat the symptoms of neurological disease and are hence powerful tools in research and clinical practice. Wireless BMIs add flexibility to both types of applications by reducing movement restrictions and risks associated with transcutaneous leads. However, since wireless implementations are typically limited in terms of transmission capacity and energy resources, the major challenge faced by their designers is to combine high performance with adaptations to limited resources. Here, we have identified three key steps in dealing with this challenge: (1) the purpose of the BMI should be clearly specified with regard to the type of information to be processed; (2) the amount of raw input data needed to fulfill the purpose should be determined, in order to avoid over- or under-dimensioning of the design; and (3) processing tasks should be allocated among the system parts such that all of them are utilized optimally with respect to computational power, wireless link capacity and raw input data requirements. We have focused on step (2) under the assumption that the purpose of the BMI (step 1) is to assess single- or multi-unit neuronal activity in the central nervous system with single-channel extracellular recordings. The reliability of this assessment depends on performance in detection and sorting of spikes. We have therefore performed absolute threshold spike detection and spike sorting with the principal component analysis and fuzzy c-means on a set of synthetic extracellular recordings, while varying the sampling rate and resolution, noise level and number of target units, and used the known ground truth to quantitatively estimate the performance. From the calculated performance curves, we have identified the sampling rate and resolution breakpoints, beyond which performance is not expected to increase by more than 1-5%. We have then estimated the performance of alternative algorithms for spike detection and spike sorting in order to examine the generalizability of our results to other algorithms. Our findings indicate that the minimization of recording noise is the primary factor to consider in the design process. In most cases, there are breakpoints for sampling rates and resolution that provide guidelines for BMI designers in terms of minimum amount raw input data that guarantees sustained performance. Such guidelines are essential during system dimensioning. Based on these findings we conclude by presenting a quantitative task-allocation scheme that can be followed to achieve optimal utilization of available resources.

Minimizing data transfer with sustained performance in wireless brain-machine interfaces.

PubMed

Thorbergsson, Palmi Thor; Garwicz, Martin; Schouenborg, Jens; Johansson, Anders J

2012-06-01

Brain-machine interfaces (BMIs) may be used to investigate neural mechanisms or to treat the symptoms of neurological disease and are hence powerful tools in research and clinical practice. Wireless BMIs add flexibility to both types of applications by reducing movement restrictions and risks associated with transcutaneous leads. However, since wireless implementations are typically limited in terms of transmission capacity and energy resources, the major challenge faced by their designers is to combine high performance with adaptations to limited resources. Here, we have identified three key steps in dealing with this challenge: (1) the purpose of the BMI should be clearly specified with regard to the type of information to be processed; (2) the amount of raw input data needed to fulfill the purpose should be determined, in order to avoid over- or under-dimensioning of the design; and (3) processing tasks should be allocated among the system parts such that all of them are utilized optimally with respect to computational power, wireless link capacity and raw input data requirements. We have focused on step (2) under the assumption that the purpose of the BMI (step 1) is to assess single- or multi-unit neuronal activity in the central nervous system with single-channel extracellular recordings. The reliability of this assessment depends on performance in detection and sorting of spikes. We have therefore performed absolute threshold spike detection and spike sorting with the principal component analysis and fuzzy c-means on a set of synthetic extracellular recordings, while varying the sampling rate and resolution, noise level and number of target units, and used the known ground truth to quantitatively estimate the performance. From the calculated performance curves, we have identified the sampling rate and resolution breakpoints, beyond which performance is not expected to increase by more than 1-5%. We have then estimated the performance of alternative algorithms for spike detection and spike sorting in order to examine the generalizability of our results to other algorithms. Our findings indicate that the minimization of recording noise is the primary factor to consider in the design process. In most cases, there are breakpoints for sampling rates and resolution that provide guidelines for BMI designers in terms of minimum amount raw input data that guarantees sustained performance. Such guidelines are essential during system dimensioning. Based on these findings we conclude by presenting a quantitative task-allocation scheme that can be followed to achieve optimal utilization of available resources.

Association between excessive BMI increase during puberty and risk of cardiovascular mortality in adult men: a population-based cohort study.

PubMed

Ohlsson, Claes; Bygdell, Maria; Sondén, Arvid; Rosengren, Annika; Kindblom, Jenny M

2016-12-01

Being overweight during childhood and adolescence is associated with increased risk of cardiovascular disease in adulthood, but the relative contribution of prepubertal childhood BMI and BMI change during puberty to adult mortality due to cardiovascular disease is unknown. We assessed the contribution of these two distinct developmental BMI parameters for cardiovascular mortality in adult men. As a part of the ongoing population-based BMI Epidemiology Study (BEST) in Gothenburg, Sweden, men born between 1945 and 1961 with information on both their childhood BMI at age 8 years and BMI change during puberty were included in the study and followed up until December, 2013. Participants who died or emigrated before age 20 years were excluded from the analysis. BMI was collected from paediatric growth charts and mandatory military conscription tests. Childhood overweight (BMI of ≥17·9 kg/m 2 ) was defined according to the Centers for Disease Control and Prevention's cutoff at 8 years of age, and BMI change during puberty was defined as the difference between young adult BMI and childhood BMI (BMI at age 20 years minus BMI at age 8 years). Information on mortality was retrieved from high quality national registers with the participants' ten-digit personal identity number. We used Cox proportional hazard regression to analyse the association between exposures and mortality. The ethics committee of the University of Gothenburg, Sweden, approved the study and waived the requirement for written informed consent. We followed 37 672 Swedish men from age 20 years for a mean of 37·8 years (1 422 185 person-years follow-up). 3188 all-cause deaths and 710 cardiovascular deaths occurred during follow-up. The correlation between childhood BMI and BMI change during puberty was marginal (r=0·06). BMI change during puberty, but not childhood BMI, was independently associated with adult all-cause and cardiovascular mortality in men. Boys that became overweight during puberty (HR 2·39; 95% CI 1·86-3·09) and boys who were overweight consistently throughout childhood and puberty (1·85; 1·28-2·67), but not boys overweight in childhood that normalised during puberty (0·99, 0·65-1·50), had increased risk of cardiovascular mortality compared with participants who were not overweight in childhood or as young adults. The association between BMI change during puberty and cardiovascular mortality was non-linear with a substantial association above a threshold of 6·7 units increase in BMI. Excessive BMI increase during puberty is a risk marker of adult cardiovascular mortality. These results indicate that BMI should be monitored during puberty to identify boys with increased risk of adult cardiovascular mortality. Swedish Research Council, the Swedish Government (under the Avtal om Läkarutbildning och Medicinsk Forskning [Agreement for Medical Education and Research]), the Lundberg Foundation, the Torsten Söderberg Foundation, the Novo Nordisk Foundation, the Knut and Alice Wallenberg Foundation, and the Anna Ahrenberg Foundation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Neurosurgery and the dawning age of Brain-Machine Interfaces

PubMed Central

Rowland, Nathan C.; Breshears, Jonathan; Chang, Edward F.

2013-01-01

Brain–machine interfaces (BMIs) are on the horizon for clinical neurosurgery. Electrocorticography-based platforms are less invasive than implanted microelectrodes, however, the latter are unmatched in their ability to achieve fine motor control of a robotic prosthesis capable of natural human behaviors. These technologies will be crucial to restoring neural function to a large population of patients with severe neurologic impairment – including those with spinal cord injury, stroke, limb amputation, and disabling neuromuscular disorders such as amyotrophic lateral sclerosis. On the opposite end of the spectrum are neural enhancement technologies for specialized applications such as combat. An ongoing ethical dialogue is imminent as we prepare for BMI platforms to enter the neurosurgical realm of clinical management. PMID:23653884

Chronic Inhibition, Self-Control and Eating Behavior: Test of a ‘Resource Depletion’ Model

PubMed Central

Hagger, Martin S.; Panetta, Giulia; Leung, Chung-Ming; Wong, Ging Ging; Wang, John C. K.; Chan, Derwin K. C.; Keatley, David A.; Chatzisarantis, Nikos L. D.

2013-01-01

The current research tested the hypothesis that individuals engaged in long-term efforts to limit food intake (e.g., individuals with high eating restraint) would have reduced capacity to regulate eating when self-control resources are limited. In the current research, body mass index (BMI) was used as a proxy for eating restraint based on the assumption that individuals with high BMI would have elevated levels of chronic eating restraint. A preliminary study (Study 1) aimed to provide evidence for the assumed relationship between eating restraint and BMI. Participants (N = 72) categorized into high or normal-range BMI groups completed the eating restraint scale. Consistent with the hypothesis, results revealed significantly higher scores on the weight fluctuation and concern for dieting subscales of the restraint scale among participants in the high BMI group compared to the normal-range BMI group. The main study (Study 2) aimed to test the hypothesized interactive effect of BMI and diminished self-control resources on eating behavior. Participants (N = 83) classified as having high or normal-range BMI were randomly allocated to receive a challenging counting task that depleted self-control resources (ego-depletion condition) or a non-depleting control task (no depletion condition). Participants then engaged in a second task in which required tasting and rating tempting cookies and candies. Amount of food consumed during the taste-and-rate task constituted the behavioral dependent measure. Regression analyses revealed a significant interaction effect of these variables on amount of food eaten in the taste-and-rate task. Individuals with high BMI had reduced capacity to regulate eating under conditions of self-control resource depletion as predicted. The interactive effects of BMI and self-control resource depletion on eating behavior were independent of trait self-control. Results extend knowledge of the role of self-control in regulating eating behavior and provide support for a limited-resource model of self-control. PMID:24146942

Maternal employment, work schedules, and children's body mass index.

PubMed

Morrissey, Taryn W; Dunifon, Rachel E; Kalil, Ariel

2011-01-01

Previous work has shown that mothers' employment is associated with increases in children's body mass index (BMI), a measure of weight for height. Nonstandard work (working evenings or nights, weekends, or an irregular shift) may also be associated with children's BMI. This article examines the association between maternal work and children's BMI and considers the influence of mothers' nonstandard work schedules. Using data from school-age children (approximately 8 to 12 years) in the NICHD's Study of Early Child Care and Youth Development (N = 990), this study found that an increase in the total time a mother is employed is associated with an increase in her child's BMI; additionally, the association between maternal employment and children's weight is much stronger at 6th grade relative to younger ages. There was no evidence that maternal or home characteristics or children's time use mediated these associations, nor was there any evidence that nonstandard work was associated with children's BMI. Implications for policy and future research are discussed. © 2011 The Authors. Child Development © 2011 Society for Research in Child Development, Inc.

How different data sources and definitions of neighbourhood influence the association between food outlet availability and body mass index: a cross-sectional study.

PubMed

Hobbs, Matthew; Green, Mark; Griffiths, Claire; Jordan, Hannah; Saunders, Joanna; McKenna, Jim

2017-05-01

Inconsistencies in methodologies continue to inhibit understanding of the impact of the environment on body mass index (BMI). To estimate the effect of these differences, we assessed the impact of using different definitions of neighbourhood and data sets on associations between food outlet availability within the environment and BMI. Previous research has not extended this to show any differences in the strength of associations between food outlet availability and BMI across both different definitions of neighbourhood and data sets. Descriptive statistics showed differences in the number of food outlets, particularly other food retail outlets between different data sets and definitions of neighbourhood. Despite these differences, our key finding was that across both different definitions of neighbourhood and data sets, there was very little difference in size of associations between food outlets and BMI. Researchers should consider and transparently report the impact of methodological choices such as the definition of neighbourhood and acknowledge any differences in associations between the food environment and BMI.

Concordance of self-report and measured height and weight of college students.

PubMed

Quick, Virginia; Byrd-Bredbenner, Carol; Shoff, Suzanne; White, Adrienne A; Lohse, Barbara; Horacek, Tanya; Kattelmann, Kendra; Phillips, Beatrice; Hoerr, Sharon L; Greene, Geoffrey

2015-01-01

This study examined associations between college students' self-report and measured height and weight. Participants (N = 1,686) were 77% white, 62% female, aged 18-24 years (mean ± SD, 19.1 ± 1.1 years), and enrolled at 8 US universities. Body mass index (BMI) was calculated for self-report (via online survey); trained researchers measured height and weight and categorized them as normal (18.5 to < 25), overweight (25 to < 30), obese (30 to < 35), and morbidly obese (≥ 35). Concordance of self-report vs objectively measured BMI groups using chi-square revealed that 93% were accurate, 4% were underestimated, and 2.7% were overestimated. Pearson correlations and adjusted linear regression revealed significant associations between self-report and measured BMI (r = .97; P < .001) and BMI adjusted for age, gender, and race/ethnicity (R² = .94). Concordance was also high between BMI categories (kappa = 0.77; P < .001). Findings provide support for the utility of self-report height and weight for survey research in college students. Copyright © 2015 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Prognostic Significance of BMI-1 But Not MEL-18 Expression in Pulmonary Squamous Cell Carcinoma.

PubMed

Abe, Sosei; Yamashita, Shin-Ichi; Miyahara, S O; Wakahara, Junichi; Yamamoto, Leona; Mori, Ryo; Imamura, Naoko; Yoshida, Yasuhiro; Waseda, Ryuichi; Hiratsuka, Masafumi; Shiraishi, Takeshi; Nabeshima, Kazuki; Iwasaki, Akinori

2017-04-01

We investigated the possibility of BMI-1 and MEL-18 to predict survival in patients with pulmonary squamous cell carcinoma. One hundred and ninety-nine patients underwent surgery in our Institute between 1995 and 2005. We used immunohistochemical (IHC) analysis to determine the expressions of BMI-1 and MEL-18 and compared them with clinicopathological factors and survival. Forty-one of 199 cases (21%) were BMI-1-positive. No correlation was found between BMI-1 and MEL-18 expression by IHC and clinicopathological factors. Five-year overall survival in the BMI-1-positive group (66.8%), but not MEL-18, was significantly better than that in the negative group (45.5%, p=0.04). In multivariate analysis, positive BMI-1 was a better prognostic factor of overall survival (hazard ratio (HR)=0.561, 95% confidence interval (CI)=0.271-1.16, p=0.12). BMI-1 expression, but not MEL-18, is associated with a favorable prognosis and is a possible prognostic factor of pulmonary squamous cell carcinoma. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Bmi-1: At the crossroads of physiological and pathological biology

PubMed Central

Bhattacharya, Resham; Mustafi, Soumyajit Banerjee; Street, Mark; Dey, Anindya; Dwivedi, Shailendra Kumar Dhar

2015-01-01

Bmi-1 is a member of the Polycomb Repressor Complex1 that mediates gene silencing by regulating chromatin structure and is indispensable for self-renewal of both normal and cancer stem cells. Despite three decades of research that have elucidated the transcriptional regulation, post-translational modifications and functions of Bmi-1 in regulating the DNA damage response, cellular bioenergetics, and pathologies, the entire potential of a protein with such varied function remains to be realized. This review attempts to synthesize the current knowledge on Bmi-1 with an emphasis on its role in both normal physiology and cancer. Additionally, since cancer stem cells are emerging as a new paradigm for therapy resistance, the role of Bmi-1 in this perspective is also highlighted. The wide spectrum of malignancies that implicate Bmi-1 as a signature for stemness and oncogenesis also make it a suitable candidate for therapy. Nonetheless new approaches are vitally needed to further characterize physiological roles of Bmi-1 with the long-term goal of using Bmi-1 as a prognostic marker and a therapeutic target. PMID:26448339

Regional differences as barriers to body mass index screening described by Ohio school nurses.

PubMed

Stalter, Ann M; Chaudry, Rosemary V; Polivka, Barbara J

2011-08-01

Body mass index (BMI) screening is advocated by the National Association of School Nurses (NASN). Research identifying barriers to BMI screening in public elementary school settings has been sparse. The purpose of the study was to identify barriers and facilitating factors of BMI screening practices among Ohio school nurses working in suburban, rural, and urban public elementary schools. This descriptive study used focus groups with 25 school nurses in 3 geographic regions of Ohio. An adapted Healthy People 2010 model guided the development of semistructured focus group questions. Nine regional themes related to BMI screening emerged specific to suburban, rural, and/or urban school nurses' experiences with BMI screening practice, policy, school physical environment, school social environment, school risk/protection, and access to quality health care. Key facilitating factors to BMI screening varied by region. Key barriers to BMI screening were a lack of privacy, time, policy, and workload of school nurses. Regionally specific facilitating factors to BMI screening in schools provide opportunities for schools to accentuate the positive and to promote school health. © 2011, American School Health Association.

Restoration of Hindlimb Movements after Complete Spinal Cord Injury Using Brain-Controlled Functional Electrical Stimulation.

PubMed

Knudsen, Eric B; Moxon, Karen A

2017-01-01

Single neuron and local field potential signals recorded in the primary motor cortex have been repeatedly demonstrated as viable control signals for multi-degree-of-freedom actuators. Although the primary source of these signals has been fore/upper limb motor regions, recent evidence suggests that neural adaptation underlying neuroprosthetic control is generalizable across cortex, including hindlimb sensorimotor cortex. Here, adult rats underwent a longitudinal study that included a hindlimb pedal press task in response to cues for specific durations, followed by brain machine interface (BMI) tasks in healthy rats, after rats received a complete spinal transection and after the BMI signal controls epidural stimulation (BMI-FES). Over the course of the transition from learned behavior to BMI task, fewer neurons were responsive after the cue, the proportion of neurons selective for press duration increased and these neurons carried more information. After a complete, mid-thoracic spinal lesion that completely severed both ascending and descending connections to the lower limbs, there was a reduction in task-responsive neurons followed by a reacquisition of task selectivity in recorded populations. This occurred due to a change in pattern of neuronal responses not simple changes in firing rate. Finally, during BMI-FES, additional information about the intended press duration was produced. This information was not dependent on the stimulation, which was the same for short and long duration presses during the early phase of stimulation, but instead was likely due to sensory feedback to sensorimotor cortex in response to movement along the trunk during the restored pedal press. This post-cue signal could be used as an error signal in a continuous decoder providing information about the position of the limb to optimally control a neuroprosthetic device.

The shape of beauty: determinants of female physical attractiveness.

PubMed

Fisher, Maryanne L; Voracek, Martin

2006-06-01

Rarely has one research area gained as much attention as that which is observed for female physical attractiveness. The past decade has resulted in numerous, exciting developments, particularly with respect to three proposed determinants of beauty: waist to hip ratio (WHR), body mass index (BMI), and curvaceousness. The goal of our paper is to provide a highly necessary review of contemporary research on the female attractiveness, including an in-depth examination of these factors. In our review, we first discuss WHR, an index of fat deposition, which is calculated by measuring the circumference of the waist compared to the circumference of the hips. WHR is controlled by the sex hormones, and increases as women age, and hence, may influence perceptions of attractiveness. This factor has been hotly contested, as some researchers have claimed that a WHR of approximately 0.7 is universally most attractive, whereas others have found inconsistent findings, or suggest the importance of other factors, such as BMI. Body mass index (BMI), calculated by dividing the body weight (in kilograms) by height (in meters) squared, serves as a measure of body fat. Although WHR and BMI are correlated, they lead to different conclusions, and the importance of BMI as a measure of female attractiveness is debated in the literature. Similar to WHR research, BMI and its role in attractiveness is not cross-culturally consistent and is affected by the availability of resources within a given environment. It may be the case that both WHR and BMI influence female attractiveness. However, there has been little investigation of this possibility. We have explored this issue in our research, which revealed that both influence attractiveness, but in addition, we noticed that curvaceousness was also a factor. Curvaceousness is the degree of "hourglass" shape as determined, for example, by the size of the bust, relative to the circumference of the hips and waist, and the size of the buttocks. However, curvaceousness does not appear to be temporally stable as a marker of attractiveness, and it is not consistent across modes of presentation. For example, models in male-oriented magazines are more curvaceous than models in female-oriented magazines. In summary, faced with these recent findings, it is difficult to ascertain agreement among the various factors, especially when researchers investigate each determinant in isolation. We conclude that, although researchers have made many important initial steps in examining female attractiveness, there remains much to be discovered.

Antitumor activity and inhibitory effects on cancer stem cell-like properties of Adeno-associated virus (AAV) -mediated Bmi-1 interference driven by Bmi-1 promoter for gastric cancer

PubMed Central

Wang, Xiaofeng; Liu, Xinyang; Huang, Mingzhu; Gan, Lu; Cheng, Yufan; Li, Jin

2016-01-01

Bmi-1 is aberrantly activated in various cancers and plays a vital role in maintaining the self-renewal of stem cells. Our previous research revealed that Bmi-1 was overexpressed in gastric cancer (GC) and it's overexpression was an independent negative prognostic factor, suggesting it can be a therapeutic target. The main purpose of this investigation was to explore the antitumor activity of Bmi-1 interference driven by its own promoter (Ad-Bmi-1i) for GC. In this study, we used adenoviral vector to deliver Bmi-1 shRNA driven by its own promoter to treat GC. Our results revealed that Ad-Bmi-1i could selectively silence Bmi-1 in GC cells which overexpress Bmi-1 and suppress the malignant phenotypes and stem-like properties of GC cells in vitro and in vivo. Moreover, direct injection of Ad-Bmi-1i into xenografts suppressed tumor growth and destroyed cancer cells in vivo. Ad-Bmi-1i inhibited the proliferation of GC cells mainly via inducing senescence in vitro, but it suppressed tumor through inducing senescence and apoptosis, and inhibiting angiogenesis in vivo. Bmi-1 knockdown by Ad-Bmi-1i downregulated VEGF via inhibiting AKT activity. These results suggest that Ad-Bmi-1i not only inhibits tumor growth and stem cell-like phenotype by inducing cellular senescence directly, but also has an indirect anti-tumor activity by anti-angiogenesis effects via regulating PTEN/AKT/VEGF pathway. Transfer of gene interference guided by its own promoter by an adeno-associated virus (AAV) vector might be a potent antitumor approach for cancer therapy. PMID:27009837

Motivational Interviewing and Dietary Counseling for Obesity in Primary Care: An RCT

PubMed Central

McMaster, Fiona; Bocian, Alison; Harris, Donna; Zhou, Yan; Snetselaar, Linda; Schwartz, Robert; Myers, Esther; Gotlieb, Jaquelin; Foster, Jan; Hollinger, Donna; Smith, Karen; Woolford, Susan; Mueller, Dru; Wasserman, Richard C.

2015-01-01

BACKGROUND AND OBJECTIVE: Few studies have tested the impact of motivational interviewing (MI) delivered by primary care providers on pediatric obesity. This study tested the efficacy of MI delivered by providers and registered dietitians (RDs) to parents of overweight children aged 2 through 8. METHODS: Forty-two practices from the Pediatric Research in Office Settings Network of the American Academy of Pediatrics were randomly assigned to 1 of 3 groups. Group 1 (usual care) measured BMI percentile at baseline and 1- and 2-year follow-up. Group 2 (provider only) delivered 4 MI counseling sessions to parents of the index child over 2 years. Group 3 (provider + RD) delivered 4 provider MI sessions plus 6 MI sessions from a RD. The primary outcome was child BMI percentile at 2-year follow up. RESULTS: At 2-year follow-up, the adjusted BMI percentile was 90.3, 88.1, and 87.1 for groups 1, 2, and 3, respectively. The group 3 mean was significantly (P = .02) lower than group 1. Mean changes from baseline in BMI percentile were 1.8, 3.8, and 4.9 across groups 1, 2, and 3. CONCLUSIONS: MI delivered by providers and RDs (group 3) resulted in statistically significant reductions in BMI percentile. Research is needed to determine the clinical significance and persistence of the BMI effects observed. How the intervention can be brought to scale (in particular, how to train physicians to use MI effectively and how best to train RDs and integrate them into primary care settings) also merits future research. PMID:25825539

Social disparities in body mass index (BMI) trajectories among Chinese adults in 1991-2011.

PubMed

Fang, Changchun; Liang, Ying

2017-08-16

Obesity is a serious public health problem in China. The relationship between obesity and socio-economic status (SES) is changing and affected by uncertainty, particularly, in developing countries. The sex-related differences in body mass index (BMI) trajectories are controversial and require substantial empirical data for updating and enriching. This study examined the relationship between SES and BMI in Chinese adults from a dynamic perspective using longitudinal data (1991-2011) from the China Health and Nutrition Survey (CHNS). Then, sex-related differences were determined. A hierarchical linear model was used. SES positively affected the male BMI changes, with faster BMI growth rates in the high-SES males over the past 20 years. By contrast, female BMI was only affected by BMI baseline and residential area. Specifically, greater BMI baseline led to greater BMI growth rate and earlier BMI decline. In the past 20 years, the BMI growth rate has been greater in the urban females than in the rural females. The relationship between SES and obesity is complex in China, and a substantial sex-related difference exists. We argue that this large sex-related difference is due to the rapid economic and social changes that have affected national health and increased the gender inequality and social role restrictions in females. We provide insights for further research and policy recommendations.

BMI-1 Mediates Estrogen-Deficiency-Induced Bone Loss by Inhibiting Reactive Oxygen Species Accumulation and T Cell Activation.

PubMed

Li, Jinbo; Wang, Qian; Yang, Renlei; Zhang, Jiaqi; Li, Xing; Zhou, Xichao; Miao, Dengshun

2017-05-01

Previous studies have shown that estrogen regulates bone homeostasis through regulatory effects on oxidative stress. However, it is unclear how estrogen deficiency triggers reactive oxygen species (ROS) accumulation. Recent studies provide evidence that the B lymphoma Mo-MLV insertion region 1 (BMI-1) plays a critical role in protection against oxidative stress and that this gene is directly regulated by estrogen via estrogen receptor (ER) at the transcriptional level. In this study, ovariectomized mice were given drinking water with/without antioxidant N-acetyl-cysteine (NAC, 1 mg/mL) supplementation, and compared with each other and with sham mice. Results showed that ovariectomy resulted in bone loss with increased osteoclast surface, increased ROS levels, T cell activation, and increased TNF and RANKL levels in serum and in CD4 T cells; NAC supplementation largely prevented these alterations. BMI-1 expression levels were dramatically downregulated in CD4 T cells from ovariectomized mice. We supplemented drinking water to BMI-1-deficient mice with/without NAC and compared them with each other and with wild-type (WT) mice. We found that BMI-1 deficiency mimicked alterations observed in ovariectomy whereas NAC supplementation reversed all alterations induced by BMI-1 deficiency. Because T cells are critical in mediating ovariectomy-induced bone loss, we further assessed whether BMI-1 overexpression in lymphocytes can protect against estrogen deficiency-induced osteoclastogenesis and bone loss by inhibiting oxidative stress, T cell activation, and RANKL production. When WT and Eμ-BMI-1 transgenic mice with BMI-1 specifically overexpressed in lymphocytes were ovariectomized and compared with each other and with WT sham mice, we found that BMI-1 overexpression in lymphocytes clearly reversed all alterations induced by ovariectomy. Results from this study indicate that estrogen deficiency downregulates BMI-1 and subsequently increases ROS, T cell activation, and RANKL production in T cells, thus enhancing osteoclastogenesis and accelerating bone loss. This study clarifies a novel mechanism regulating estrogen deficiency-induced bone loss. © 2016 American Society for Bone and Mineral Research. © 2016 American Society for Bone and Mineral Research.

AMIA Board white paper: definition of biomedical informatics and specification of core competencies for graduate education in the discipline

PubMed Central

Kulikowski, Casimir A; Shortliffe, Edward H; Currie, Leanne M; Elkin, Peter L; Hunter, Lawrence E; Johnson, Todd R; Kalet, Ira J; Lenert, Leslie A; Musen, Mark A; Ozbolt, Judy G; Smith, Jack W; Tarczy-Hornoch, Peter Z

2012-01-01

The AMIA biomedical informatics (BMI) core competencies have been designed to support and guide graduate education in BMI, the core scientific discipline underlying the breadth of the field's research, practice, and education. The core definition of BMI adopted by AMIA specifies that BMI is ‘the interdisciplinary field that studies and pursues the effective uses of biomedical data, information, and knowledge for scientific inquiry, problem solving and decision making, motivated by efforts to improve human health.’ Application areas range from bioinformatics to clinical and public health informatics and span the spectrum from the molecular to population levels of health and biomedicine. The shared core informatics competencies of BMI draw on the practical experience of many specific informatics sub-disciplines. The AMIA BMI analysis highlights the central shared set of competencies that should guide curriculum design and that graduate students should be expected to master. PMID:22683918

The Relationship of School Absenteeism with Body Mass Index, Academic Achievement, and Socioeconomic Status among Fourth-Grade Children

PubMed Central

Royer, Julie A.; Hardin, James W.; Guinn, Caroline H.; Devlin, Christina M.

2014-01-01

Background Data from a school-based study concerning fourth-grade children’s dietary recall accuracy were linked with data from the South Carolina Department of Education (SCDE) through the South Carolina Budget and Control Board Office of Research and Statistics (ORS) to investigate the relationships of children’s school absenteeism with body mass index (BMI), academic achievement, and socioeconomic status (SES). Methods Data for all variables were available for 920 fourth-grade children during two school years (2005–2006, 2006–2007). Number of school days absent for each child and eligibility for free/reduced-price school meals (SES measure) were provided to ORS by SCDE. Children’s weight and height were measured by research staff; age/sex specific BMI percentile was calculated and grouped into categories. For academic achievement, Palmetto Achievement Challenge Tests scores were provided by the school district. The associations of absenteeism with BMI, academic achievement, SES, and school year were investigated with logistic binomial models using the modified sandwich variance estimator to adjust for multiple outcomes within schools. Results The relationships between absenteeism and each of BMI percentile category and SES were not significant (all coefficient p values > 0.118). The relationship between absenteeism and academic achievement was inversely significant (p value < 0.0001; coefficient = −0.087). Conclusions These results support the inverse relationship between absenteeism and academic achievement that was expected and has been found by other researchers. The lack of significant results concerning the relationships between absenteeism and both BMI and SES disagrees with earlier, limited research. More research to investigate these relationships is needed. PMID:21668882

Redundant information encoding in primary motor cortex during natural and prosthetic motor control.

PubMed

So, Kelvin; Ganguly, Karunesh; Jimenez, Jessica; Gastpar, Michael C; Carmena, Jose M

2012-06-01

Redundant encoding of information facilitates reliable distributed information processing. To explore this hypothesis in the motor system, we applied concepts from information theory to quantify the redundancy of movement-related information encoded in the macaque primary motor cortex (M1) during natural and neuroprosthetic control. Two macaque monkeys were trained to perform a delay center-out reaching task controlling a computer cursor under natural arm movement (manual control, 'MC'), and using a brain-machine interface (BMI) via volitional control of neural ensemble activity (brain control, 'BC'). During MC, we found neurons in contralateral M1 to contain higher and more redundant information about target direction than ipsilateral M1 neurons, consistent with the laterality of movement control. During BC, we found that the M1 neurons directly incorporated into the BMI ('direct' neurons) contained the highest and most redundant target information compared to neurons that were not incorporated into the BMI ('indirect' neurons). This effect was even more significant when comparing to M1 neurons of the opposite hemisphere. Interestingly, when we retrained the BMI to use ipsilateral M1 activity, we found that these neurons were more redundant and contained higher information than contralateral M1 neurons, even though ensembles from this hemisphere were previously less redundant during natural arm movement. These results indicate that ensembles most associated to movement contain highest redundancy and information encoding, which suggests a role for redundancy in proficient natural and prosthetic motor control.

Actigraphy-Derived Daily Rest-Activity Patterns and Body Mass Index in Community-Dwelling Adults.

PubMed

Cespedes Feliciano, Elizabeth M; Quante, Mirja; Weng, Jia; Mitchell, Jonathan A; James, Peter; Marinac, Catherine R; Mariani, Sara; Redline, Susan; Kerr, Jacqueline; Godbole, Suneeta; Manteiga, Alicia; Wang, Daniel; Hipp, J Aaron

2017-12-01

To examine associations between 24-hour rest-activity patterns and body mass index (BMI) among community-dwelling US adults. Rest-activity patterns provide a field method to study exposures related to circadian rhythms. Adults (N = 578) wore an actigraph on their nondominant wrist for 7 days. Intradaily variability and interdaily stability (IS), M10 (most active 10-hours), L5 (least active 5-hours), and relative amplitude (RA) were derived using nonparametric rhythm analysis. Mesor, acrophase, and amplitude were calculated from log-transformed count data using the parametric cosinor approach. Participants were 80% female and mean (standard deviation) age was 52 (15) years. Participants with higher BMI had lower values for magnitude, RA, IS, total sleep time (TST), and sleep efficiency. In multivariable analyses, less robust 24-hour rest-activity patterns as represented by lower RA were consistently associated with higher BMI: comparing the bottom quintile (least robust) to the top quintile (most robust 24-hour rest-activity pattern) of RA, BMI was 3-kg/m2 higher (p = .02). Associations were similar in magnitude to an hour less of TST (1-kg/m2 higher BMI) or a 10% decrease in sleep efficiency (2-kg/m2 higher BMI), and independent of age, sex, race, education, and the duration of rest and/or activity. Lower RA, reflecting both higher night activity and lower daytime activity, was associated with higher BMI. Independent of the duration of rest or activity during the day or night, 24-hour rest, and activity patterns from actigraphy provide aggregated measures of activity that associate with BMI in community-dwelling adults. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Demonstration of a Semi-Autonomous Hybrid Brain-Machine Interface using Human Intracranial EEG, Eye Tracking, and Computer Vision to Control a Robotic Upper Limb Prosthetic

PubMed Central

McMullen, David P.; Hotson, Guy; Katyal, Kapil D.; Wester, Brock A.; Fifer, Matthew S.; McGee, Timothy G.; Harris, Andrew; Johannes, Matthew S.; Vogelstein, R. Jacob; Ravitz, Alan D.; Anderson, William S.; Thakor, Nitish V.; Crone, Nathan E.

2014-01-01

To increase the ability of brain-machine interfaces (BMIs) to control advanced prostheses such as the modular prosthetic limb (MPL), we are developing a novel system: the Hybrid Augmented Reality Multimodal Operation Neural Integration Environment (HARMONIE). This system utilizes hybrid input, supervisory control, and intelligent robotics to allow users to identify an object (via eye tracking and computer vision) and initiate (via brain-control) a semi-autonomous reach-grasp-and-drop of the object by the MPL. Sequential iterations of HARMONIE were tested in two pilot subjects implanted with electrocorticographic (ECoG) and depth electrodes within motor areas. The subjects performed the complex task in 71.4% (20/28) and 67.7% (21/31) of trials after minimal training. Balanced accuracy for detecting movements was 91.1% and 92.9%, significantly greater than chance accuracies (p < 0.05). After BMI-based initiation, the MPL completed the entire task 100% (one object) and 70% (three objects) of the time. The MPL took approximately 12.2 seconds for task completion after system improvements implemented for the second subject. Our hybrid-BMI design prevented all but one baseline false positive from initiating the system. The novel approach demonstrated in this proof-of-principle study, using hybrid input, supervisory control, and intelligent robotics, addresses limitations of current BMIs. PMID:24760914

Demonstration of a semi-autonomous hybrid brain-machine interface using human intracranial EEG, eye tracking, and computer vision to control a robotic upper limb prosthetic.

PubMed

McMullen, David P; Hotson, Guy; Katyal, Kapil D; Wester, Brock A; Fifer, Matthew S; McGee, Timothy G; Harris, Andrew; Johannes, Matthew S; Vogelstein, R Jacob; Ravitz, Alan D; Anderson, William S; Thakor, Nitish V; Crone, Nathan E

2014-07-01

To increase the ability of brain-machine interfaces (BMIs) to control advanced prostheses such as the modular prosthetic limb (MPL), we are developing a novel system: the Hybrid Augmented Reality Multimodal Operation Neural Integration Environment (HARMONIE). This system utilizes hybrid input, supervisory control, and intelligent robotics to allow users to identify an object (via eye tracking and computer vision) and initiate (via brain-control) a semi-autonomous reach-grasp-and-drop of the object by the MPL. Sequential iterations of HARMONIE were tested in two pilot subjects implanted with electrocorticographic (ECoG) and depth electrodes within motor areas. The subjects performed the complex task in 71.4% (20/28) and 67.7% (21/31) of trials after minimal training. Balanced accuracy for detecting movements was 91.1% and 92.9%, significantly greater than chance accuracies (p < 0.05). After BMI-based initiation, the MPL completed the entire task 100% (one object) and 70% (three objects) of the time. The MPL took approximately 12.2 s for task completion after system improvements implemented for the second subject. Our hybrid-BMI design prevented all but one baseline false positive from initiating the system. The novel approach demonstrated in this proof-of-principle study, using hybrid input, supervisory control, and intelligent robotics, addresses limitations of current BMIs.

A novel bioelectronic tongue in vivo for highly sensitive bitterness detection with brain-machine interface.

PubMed

Qin, Zhen; Zhang, Bin; Hu, Liang; Zhuang, Liujing; Hu, Ning; Wang, Ping

2016-04-15

Animals' gustatory system has been widely acknowledged as one of the most sensitive chemosensing systems, especially for its ability to detect bitterness. Since bitterness usually symbolizes inedibility, the potential to use rodent's gustatory system is investigated to detect bitter compounds. In this work, the extracellular potentials of a group of neurons are recorded by chronically coupling microelectrode array to rat's gustatory cortex with brain-machine interface (BMI) technology. Local field potentials (LFPs), which represent the electrophysiological activity of neural networks, are chosen as target signals due to stable response patterns across trials and are further divided into different oscillations. As a result, different taste qualities yield quality-specific LFPs in time domain which suggests the selectivity of this in vivo bioelectronic tongue. Meanwhile, more quantitative study in frequency domain indicates that the post-stimulation power of beta and low gamma oscillations shows dependence with concentrations of denatonium benzoate, a prototypical bitter compound, and the limit of detection is deduced to be 0.076 μM, which is two orders lower than previous in vitro bioelectronic tongues and conventional electronic tongues. According to the results, this in vivo bioelectronic tongue in combination with BMI presents a promising method in highly sensitive bitterness detection and is supposed to provide new platform in measuring bitterness degree. Copyright © 2015 Elsevier B.V. All rights reserved.

Parsing learning in networks using brain-machine interfaces.

PubMed

Orsborn, Amy L; Pesaran, Bijan

2017-10-01

Brain-machine interfaces (BMIs) define new ways to interact with our environment and hold great promise for clinical therapies. Motor BMIs, for instance, re-route neural activity to control movements of a new effector and could restore movement to people with paralysis. Increasing experience shows that interfacing with the brain inevitably changes the brain. BMIs engage and depend on a wide array of innate learning mechanisms to produce meaningful behavior. BMIs precisely define the information streams into and out of the brain, but engage wide-spread learning. We take a network perspective and review existing observations of learning in motor BMIs to show that BMIs engage multiple learning mechanisms distributed across neural networks. Recent studies demonstrate the advantages of BMI for parsing this learning and its underlying neural mechanisms. BMIs therefore provide a powerful tool for studying the neural mechanisms of learning that highlights the critical role of learning in engineered neural therapies. Copyright © 2017 Elsevier Ltd. All rights reserved.

Job strain and changes in the body mass index among working women: A prospective study

PubMed Central

Fujishiro, Kaori; Lawson, Christina C.; Hibert, Eileen Lividoti; Chavarro, Jorge E.; Rich-Edwards, Janet W.

2015-01-01

Objectives The relationship between job strain and weight gain has been unclear, especially for women. Using data from over 52 000 working women, we compare the association between change in job strain and change in BMI across different levels of baseline BMI. Subjects/Methods We used data from participants in the Nurses’ Health Study II (n=52 656, mean age = 38.4), an ongoing prospective cohort study. Using linear regression, we modeled the change in BMI over 4 years as a function of the change in job strain, baseline BMI, and the interaction between the two. Change in job strain was characterized in four categories combining baseline and follow-up levels: consistently low strain [low at both points], decreased strain [high strain at baseline only], increased strain [high strain at follow-up only], and consistently high strain [high at both points]. Age, race/ethnicity, pregnancy history, job types, and health behaviors at baseline were controlled for in the model. Results In adjusted models, women who reported high job strain at least once during the four-year period had a greater increase in BMI (ΔBMI=0.06–0.12, p<0.05) than those who never reported high job strain. The association between the change in job strain exposure and the change in BMI depended on the baseline BMI level (p=0.015 for the interaction): the greater the baseline BMI, the greater the BMI gain associated with consistently high job strain. The BMI gain associated with increased or decreased job strain was uniform across the range of baseline BMI. Conclusions Women with higher BMI may be more vulnerable to BMI gain when exposed to constant work stress. Future research focusing on mediating mechanisms between job strain and BMI change should explore the possibility of differential responses to job strain by initial BMI. PMID:25986779

Self-control mediates the relationship between time perspective and BMI.

PubMed

Price, Menna; Higgs, Suzanne; Lee, Michelle

2017-01-01

Trait future time perspective measures the extent to which behaviour is dominated by a striving for future goals and rewards. Trait present time perspective measures orientation towards immediate pleasure. Previous research has explored the relationship between future and present time perspective and BMI with mixed findings. In addition, the psychological mechanism underlying this relationship is unclear. Self-control is a likely candidate, as it has been related to both BMI and time perspective, but the relationship between all of these concepts has not been examined in a single study. Therefore, the aim of this study was to examine if trait self-control mediates the relationship between time perspective (future and present) and BMI. Self-report time perspective (ZTPI), self-control (SCS) and height/weight data were collected using an online survey from a mixed student and community sample (N = 218) with wide ranging age (mean 29, SD 11, range 18-73 years) and BMI (mean 24, SD 4, range 15-43). The results of a structural equation model including both facets of time perspective suggested that the traits are related yet distinct measures that independently predict BMI through changes in self-control. Bootstrap mediation analysis showed that self-control mediated the relationship between both future time perspective (95% CI, -0.10 to -0.02) and present time perspective (95% CI, 0.03 to 0.17), and BMI in opposite directions. Participants with higher future time perspective scores (higher present time perspective scores) had higher (lower) self-control, which predicted lower (higher) BMI. These results are consistent with previous research suggesting an important role for time perspective in health outcomes. Self-control likely mediates the relationship between temporal perspectives and BMI, suggesting that time perspective may be a target for individualised interventions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Relation between milk-fat percentage, vitamin D, and BMI z score in early childhood.

PubMed

Vanderhout, Shelley M; Birken, Catherine S; Parkin, Patricia C; Lebovic, Gerald; Chen, Yang; O'Connor, Deborah L; Maguire, Jonathon L

2016-12-01

Fortified cow milk is a material contributor of vitamin D and dietary fat in children. Recommendations for children >2 y of age advise reduced milk-fat consumption to reduce childhood obesity, yet the relation between lower milk fat, vitamin D stores, and body mass index (BMI) is unclear. The primary objective was to explore the association between milk-fat percentage and both BMI z score (zBMI) and venous 25-hydroxyvitamin D [25(OH)D]; the secondary objective was to assess whether milk volume consumed modified this relation. This was a cross-sectional analysis. Healthy urban children aged 12-72 mo were recruited from 9 primary health care practices within The Applied Research Group for Kids (TARGet Kids!) research group in Toronto, Canada. We used adjusted bivariate linear regression to examine the relation between milk-fat percentage and child 25(OH)D and zBMI concurrently. Effect modification by milk volume consumed on the evaluated relations was explored with the use of an interaction term in the statistical model. Among the 2745 included children there was a positive association between milk-fat percentage and 25(OH)D (P = 0.006) and a negative association between milk-fat percentage and zBMI (P < 0.0001). Participants who drank whole milk had a 5.4-nmol/L (95% CI: 4.32, 6.54) higher median 25(OH)D concentration and a 0.72 lower (95% CI: 0.68, 0.76) zBMI score than children who drank 1% milk. Milk volume consumed modified the effect of milk-fat percentage on 25(OH)D (P = 0.003) but not on zBMI (P = 0.77). Whole milk consumption among healthy young children was associated with higher vitamin D stores and lower BMI. Longitudinal and interventional studies are needed to confirm these findings. TARGet Kids! was registered at clinicaltrials.gov as NCT01869530. © 2016 American Society for Nutrition.

Parenting Styles, Feeding Styles, Feeding Practices, and Weight Status in 4–12 Year-Old Children: A Systematic Review of the Literature

PubMed Central

Shloim, Netalie; Edelson, Lisa R.; Martin, Nathalie; Hetherington, Marion M.

2015-01-01

Childhood is a critical period in the development of obesity. Eating patterns established early in life track into later life. Therefore, parental approaches to feeding in their general parenting style, feeding styles, and specific feeding practices will have a profound impact on how children eat and grow. A systematic research review following PRISMA guidelines was conducted to identify, discuss and integrate recent research investigating the relationship between parenting styles, feeding styles, feeding practices, and body mass index (BMI) in children. Medline (Ovid), PsycINFO, Web of Science, and Food Science and Technology Abstracts were systematically searched using sensitive search strategies. Studies were limited to papers published in English between 2010 and February 2015 with participants aged 4–12 years old with outcomes including obesity, change in weight, or BMI. The search yielded 31 relevant quantitative peer-reviewed papers meeting all inclusion criteria: seven longitudinal, 23 cross-sectional, one randomized control trial. Associations between parenting style and child BMI were strongest and most consistent within the longitudinal studies. Uninvolved, indulgent or highly protective parenting was associated with higher child BMI, whereas authoritative parenting was associated with a healthy BMI. Similarly for feeding styles, indulgent feeding was consistently associated with risk of obesity within cross-sectional studies. Specific feeding practices such as restriction and pressure to eat were linked to BMI, especially within cross-sectional studies. Where child traits were measured, the feeding practice appeared to be responsive to the child, therefore restriction was applied to children with a high BMI and pressure to eat applied to children with a lower BMI. Behaviors and styles that are specific to the feeding context are consistently associated with child BMI. However, since obesity emerges over time, it is through longitudinal, carefully measured (through questionnaire and observation) studies which take account of child appetite and temperament that the association between parenting style, feeding style, specific feeding practices, and child obesity will be understood. PMID:26696920

Parenting Styles, Feeding Styles, Feeding Practices, and Weight Status in 4-12 Year-Old Children: A Systematic Review of the Literature.

PubMed

Shloim, Netalie; Edelson, Lisa R; Martin, Nathalie; Hetherington, Marion M

2015-01-01

Childhood is a critical period in the development of obesity. Eating patterns established early in life track into later life. Therefore, parental approaches to feeding in their general parenting style, feeding styles, and specific feeding practices will have a profound impact on how children eat and grow. A systematic research review following PRISMA guidelines was conducted to identify, discuss and integrate recent research investigating the relationship between parenting styles, feeding styles, feeding practices, and body mass index (BMI) in children. Medline (Ovid), PsycINFO, Web of Science, and Food Science and Technology Abstracts were systematically searched using sensitive search strategies. Studies were limited to papers published in English between 2010 and February 2015 with participants aged 4-12 years old with outcomes including obesity, change in weight, or BMI. The search yielded 31 relevant quantitative peer-reviewed papers meeting all inclusion criteria: seven longitudinal, 23 cross-sectional, one randomized control trial. Associations between parenting style and child BMI were strongest and most consistent within the longitudinal studies. Uninvolved, indulgent or highly protective parenting was associated with higher child BMI, whereas authoritative parenting was associated with a healthy BMI. Similarly for feeding styles, indulgent feeding was consistently associated with risk of obesity within cross-sectional studies. Specific feeding practices such as restriction and pressure to eat were linked to BMI, especially within cross-sectional studies. Where child traits were measured, the feeding practice appeared to be responsive to the child, therefore restriction was applied to children with a high BMI and pressure to eat applied to children with a lower BMI. Behaviors and styles that are specific to the feeding context are consistently associated with child BMI. However, since obesity emerges over time, it is through longitudinal, carefully measured (through questionnaire and observation) studies which take account of child appetite and temperament that the association between parenting style, feeding style, specific feeding practices, and child obesity will be understood.

Toward more versatile and intuitive cortical brain machine interfaces

PubMed Central

Andersen, Richard A.; Kellis, Spencer; Klaes, Christian; Aflalo, Tyson

2015-01-01

Brain machine interfaces have great potential in neuroprosthetic applications to assist patients with brain injury and neurodegenerative diseases. One type of BMI is a cortical motor prosthetic which is used to assist paralyzed subjects. Motor prosthetics to date have typically used the motor cortex as a source of neural signals for controlling external devices. The review will focus on several new topics in the arena of cortical prosthetics. These include using 1) recordings from cortical areas outside motor cortex; 2) local field potentials (LFPs) as a source of recorded signals; 3) somatosensory feedback for more dexterous control of robotics; and 4) new decoding methods that work in concert to form an ecology of decode algorithms. These new advances hold promise in greatly accelerating the applicability and ease of operation of motor prosthetics. PMID:25247368

Combining a hybrid robotic system with a bain-machine interface for the rehabilitation of reaching movements: A case study with a stroke patient.

PubMed

Resquin, F; Ibañez, J; Gonzalez-Vargas, J; Brunetti, F; Dimbwadyo, I; Alves, S; Carrasco, L; Torres, L; Pons, Jose Luis

2016-08-01

Reaching and grasping are two of the most affected functions after stroke. Hybrid rehabilitation systems combining Functional Electrical Stimulation with Robotic devices have been proposed in the literature to improve rehabilitation outcomes. In this work, we present the combined use of a hybrid robotic system with an EEG-based Brain-Machine Interface to detect the user's movement intentions to trigger the assistance. The platform has been tested in a single session with a stroke patient. The results show how the patient could successfully interact with the BMI and command the assistance of the hybrid system with low latencies. Also, the Feedback Error Learning controller implemented in this system could adjust the required FES intensity to perform the task.

Early adolescent Body Mass Index and the constructed environment.

PubMed

Jones, Randall M; Vaterlaus, J Mitchell

2014-07-01

Previous research has shown that macro-level environmental features such as access to walking trails and recreational facilities are correlated with adolescent weight. Additionally, a handful of studies have documented relationships between micro-level environmental features, such as the presence (or absence) of a television in the bedroom, and adolescent weight. In this exploratory study we focus exclusively on features of the micro-level environment by examining objects that are found within adolescent personal bedrooms in relation to the adolescent occupant's Body Mass Index score (BMI). Participants were 234 early adolescents (eighth graders and ninth graders) who lived with both biological parents and who had their own private bedroom. Discriminant analyses were used to identify the bedrooms belonging to adolescents with below and above average BMI using objects contained within the micro-level environment as discriminating variables. Bedrooms belonging to adolescents with above average BMI were more likely to contain objects associated with sedentary behavior (e.g., magazines, electronic games, dolls), whereas the bedrooms belonging to the average and below average BMI adolescents were more likely to contain objects that reflect past physical activity (e.g., trophies, souvenirs, pictures of places that they had visited). If causal connections between micro-environmental variables and adolescent BMI can be established in future longitudinal research, environmental manipulations may affect adolescent BMI. Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Influence of body mass index on movement efficiency among firefighter recruits.

PubMed

Cornell, David J; Gnacinski, Stacy L; Zamzow, Aaron; Mims, Jason; Ebersole, Kyle T

2016-06-04

Previous research has demonstrated links between musculoskeletal injury risk and measures of obesity and movement efficiency among the firefighter population. However, the influence of obesity on movement efficiency among firefighter recruits remains uninvestigated. To investigate the influence of obesity on movement efficiency measures among firefighter recruits. Measures of obesity were collected among 73 male firefighter recruits. Participants were grouped into standard body mass index (BMI) categories (normal, overweight, obese). Differences in Total Functional Movement Screen (FMS) scores and Y-Balance Test (YBT) composite scores were examined between BMI categories. In addition, the relationships between measures of obesity and movement efficiency were also examined. No significant differences in movement efficiency measures were identified between BMI categories (p > 0.05). However, significant bivariate correlations were identified between BMI (kg/m2) and Total FMS score (r = -0.235, p = 0.045), as well as between fat-free mass (FFM) and Total FMS score (r = -0.231, p = 0.049), when examined among all participants. BMI may influence measures of movement efficiency among firefighter recruits to a lesser extent than among other previously examined populations. Future research should examine the influence of other unexamined physiological variables on movement efficiency.

More controlling child-feeding practices are found among parents of boys with an average body mass index compared with parents of boys with a high body mass index.

PubMed

Brann, Lynn S; Skinner, Jean D

2005-09-01

To determine if differences existed in mothers' and fathers' perceptions of their sons' weight, controlling child-feeding practices (ie, restriction, monitoring, and pressure to eat), and parenting styles (ie, authoritarian, authoritative, and permissive) by their sons' body mass index (BMI). One person (L.S.B.) interviewed mothers and boys using validated questionnaires and measured boys' weight and height; fathers completed questionnaires independently. Subjects were white, preadolescent boys and their parents. Boys were grouped by their BMI into an average BMI group (n=25; BMI percentile between 33rd and 68th) and a high BMI group (n=24; BMI percentile > or = 85th). Multivariate analyses of variance and analyses of variance. Mothers and fathers of boys with a high BMI saw their sons as more overweight (mothers P=.03, fathers P=.01), were more concerned about their sons' weight (P<.0001, P=.004), and used pressure to eat with their sons less often than mothers and fathers of boys with an average BMI (P<.0001, P<.0001). In addition, fathers of boys with a high BMI monitored their sons' eating less often than fathers of boys with an average BMI (P=.006). No differences were found in parenting by boys' BMI groups for either mothers or fathers. More controlling child-feeding practices were found among mothers (pressure to eat) and fathers (pressure to eat and monitoring) of boys with an average BMI compared with parents of boys with a high BMI. A better understanding of the relationships between feeding practices and boys' weight is necessary. However, longitudinal research is needed to provide evidence of causal association.

Big drinkers: how BMI, gender and rules of thumb influence the free pouring of wine.

PubMed

Smarandescu, Laura; Walker, Doug; Wansink, Brian

2014-11-01

This research examines free pouring behavior and provides an account of how Body Mass Index (BMI) and gender might lead to the overpouring, and consequently the overconsumption of wine. An observational study with young adults investigated how BMI and gender affect free-pouring of wine over a variety of pouring scenarios, and how rules-of-thumb in pouring affect the quantities of alcohol poured by men and women across BMI categories. For men, the amount poured was positively related to BMI. However, BMI did not affect pours by women. The use of the "half glass" rule-of-thumb in pouring reduced the volume of wine poured by over 20% for both men and women. Importantly, this rule-of-thumb substantially attenuated the pours by men at high BMI levels. Increasing awareness of pouring biases represents an early and effective step toward curbing alcohol consumption among men, and especially those who are overweight. Additionally, using a simple "half glass" rule-of-thumb may be an effective way to curb overpouring, despite non-standard glass sizes. Copyright © 2014. Published by Elsevier B.V.

Facial affective reactions to bitter-tasting foods and body mass index in adults.

PubMed

Garcia-Burgos, D; Zamora, M C

2013-12-01

Differences in food consumption among body-weight statuses (e.g., higher fruit intake linked with lower body mass index (BMI) and energy-dense products with higher BMI) has raised the question of why people who are overweight or are at risk of becoming overweight eat differently from thinner people. One explanation, in terms of sensitivity to affective properties of food, suggests that palatability-driven consumption is likely to be an important contributor to food intake, and therefore body weight. Extending this approach to unpalatable tastes, we examined the relationship between aversive reactions to foods and BMI. We hypothesized that people who have a high BMI will show more negative affective reactions to bitter-tasting stimuli, even after controlling for sensory perception differences. Given that hedonic reactions may influence consumption even without conscious feelings of pleasure/displeasure, the facial expressions were included in order to provide more direct access to affective systems than subjective reports. Forty adults (28 females, 12 males) participated voluntarily. Their ages ranged from 18 to 46 years (M=24.2, SD=5.8). On the basis of BMI, participants were classified as low BMI (BMI<20; n=20) and high BMI (BMI>23; n=20). The mean BMI was 19.1 for low BMI (SD=0.7) and 25.2 for high BMI participants (SD=1.8). Each subject tasted 5 mL of a grapefruit juice drink and a bitter chocolate drink. Subjects rated the drinks' hedonic and incentive value, familiarity and bitter intensity immediately after each stimulus presentation. The results indicated that high BMI participants reacted to bitter stimuli showing more profound changes from baseline in neutral and disgust facial expressions compared with low BMI. No differences between groups were detected for the subjective pleasantness and familiarity. The research here is the first to examine how affective facial reactions to bitter food, apart from taste responsiveness, can predict differences in BMI. Copyright © 2013 Elsevier Ltd. All rights reserved.

Trends in group inequalities and interindividual inequalities in BMI in the United States, 1993-2012.

PubMed

Krishna, Aditi; Razak, Fahad; Lebel, Alexandre; Smith, George Davey; Subramanian, S V

2015-03-01

Marked increases in mean body mass index (BMI) and prevalence of obesity and overweight in the United States are well known. However, whether these average increases were accompanied by changing dispersion (or SD) remains understudied. We investigated population-level changes in the BMI distribution over time to understand how changes in dispersion reflect between-group compared with within-group inequalities in weight gain in the United States. Using data from the Behavioral Risk Factor Surveillance System survey (1993-2012), we analyzed associations between mean, SD, and median BMI and BMI at the 5th and 95th percentiles for 3,050,992 non-Hispanic white, non-Hispanic black, and Hispanic men and women aged 25-64 y. Overall, an increase of 1.0 in mean BMI (in kg/m²) was associated with an increase of 0.70 (95% CI: 0.67, 0.73) in the SD of BMI. A change of 1.0 in median BMI was associated with a change of 0.18 (95% CI: 0.14, 0.21) in the BMI value at the 5th percentile compared with a change of 2.94 (95% CI: 2.81, 3.07) at the 95th percentile. Quantile-quantile plots showed unequal changes in the BMI distribution, with pronounced changes at higher percentiles. Similar patterns were observed in subgroups stratified by sex, race-ethnicity, and education with non-Hispanic black women and women with less than a high school education having highest mean BMI, SD of BMI, and BMI values at the 5th and 95th percentiles. Mean BMI and the percentage of overweight and obese individuals do not fully describe population changes in BMI. Increases in within-group inequality in BMI represent an underrecognized characteristic of population-level weight gain. Crucially, similar increases in dispersion within groups suggest that growing inequalities in BMI at the population level are not driven by these socioeconomic and demographic factors. Future research should focus on understanding factors driving inequalities in weight gain between individuals. © 2015 American Society for Nutrition.

Relationship between Burnout and Body Mass Index in Senior and Middle Managers from the Mexican Manufacturing Industry

PubMed Central

2018-01-01

This research relates Burnout Syndrome (BS) with the Body Mass Index (BMI) among middle and senior managers of the Mexican manufacturing industry. Even though BS incidence is high in the Mexican industrial population, few systematic studies have explored BS and its relationship with other health problems, such as obesity. The goal of this research is to determine the relationship between BS and the BMI in employees with normal weight, overweight, and obesity. We present three structural equation models to relate BS and the BMI. The BMI ranges were determined according to the parameters (normal weight, overweight, and obesity) proposed by the World Health Organization (WHO). The sample includes 361 employees that voluntarily answered a 31-item questionnaire. We measure the levels of BS using the Maslach Burnout Inventory–General Survey (MBI-GS) and analyze anthropometric and sociodemographic data from the participants. Then, we determine the relationships between the variables through structural equation models and estimate the direct, indirect, and total effects in the three models, which show acceptable reliability. As main findings, the normal weight model has a larger explanatory power than the overweight and obesity models. The same research hypotheses were tested and the effects of BS on the BMI differ across the three models. Such results are presented by taking into account that obesity and overweight require additional factors, such as genetic factors and personal eating habits, to be better explained. PMID:29562619

Relationship between Burnout and Body Mass Index in Senior and Middle Managers from the Mexican Manufacturing Industry.

PubMed

Armenta-Hernández, Oziely Daniela; Maldonado-Macías, Aidé; García-Alcaraz, Jorge; Avelar-Sosa, Liliana; Realyvasquez-Vargas, Arturo; Serrano-Rosa, Miguel Angel

2018-03-17

This research relates Burnout Syndrome (BS) with the Body Mass Index (BMI) among middle and senior managers of the Mexican manufacturing industry. Even though BS incidence is high in the Mexican industrial population, few systematic studies have explored BS and its relationship with other health problems, such as obesity. The goal of this research is to determine the relationship between BS and the BMI in employees with normal weight, overweight, and obesity. We present three structural equation models to relate BS and the BMI. The BMI ranges were determined according to the parameters (normal weight, overweight, and obesity) proposed by the World Health Organization (WHO). The sample includes 361 employees that voluntarily answered a 31-item questionnaire. We measure the levels of BS using the Maslach Burnout Inventory-General Survey (MBI-GS) and analyze anthropometric and sociodemographic data from the participants. Then, we determine the relationships between the variables through structural equation models and estimate the direct, indirect, and total effects in the three models, which show acceptable reliability. As main findings, the normal weight model has a larger explanatory power than the overweight and obesity models. The same research hypotheses were tested and the effects of BS on the BMI differ across the three models. Such results are presented by taking into account that obesity and overweight require additional factors, such as genetic factors and personal eating habits, to be better explained.

B lymphoma Moloney murine leukemia virus insertion region 1: An oncogenic mediator in prostate cancer.

PubMed

Liu, Qipeng; Li, Qiaqia; Zhu, Sen; Yi, Yang; Cao, Qi

2018-06-01

B lymphoma Moloney murine leukemia virus insertion region 1 (BMI1), a core member of polycomb repressive complex 1 (PRC1), has been intensely investigated in the field of cancer epigenetics for decades. Widely known as a critical regulator in cellular physiology, BMI1 is essential in self-renewal and differentiation in different lineages of stem cells. BMI1 also plays a significant role in cancer etiology for its involvement in pathological progress such as epithelial-mesenchymal transition (EMT) and cancer stem cell maintenance, propagation, and differentiation. Importantly, overexpression of BMI1 is predictive for drug resistance, tumor recurrence, and eventual therapy failure of various cancer subtypes, which renders the pharmacological targeting at BMI1 as a novel and promising therapeutic approach. The study on prostate cancer, a prevalent hormone-related cancer among men, has promoted enormous research advancements in cancer genetics and epigenetics. This review summarizes the role of BMI1 as an oncogenic and epigenetic regulator in tumor initiation, progression, and relapse of prostate cancer.

Relationship of nutritional risk, Body Mass Index (BMI), and cognitive functioning in preschoolers

USDA-ARS?s Scientific Manuscript database

Objective: To determine the relationships, if any, between nutritional risk, BMI z-score, and cognitive function in preschoolers. Background: Excessive adipose tissue found in obesity places children at increased health risk. Considerable research has documented that obesity leads to increased ri...

Chronic, Wireless Recordings of Large Scale Brain Activity in Freely Moving Rhesus Monkeys

PubMed Central

Schwarz, David A.; Lebedev, Mikhail A.; Hanson, Timothy L.; Dimitrov, Dragan F.; Lehew, Gary; Meloy, Jim; Rajangam, Sankaranarayani; Subramanian, Vivek; Ifft, Peter J.; Li, Zheng; Ramakrishnan, Arjun; Tate, Andrew; Zhuang, Katie; Nicolelis, Miguel A.L.

2014-01-01

Advances in techniques for recording large-scale brain activity contribute to both the elucidation of neurophysiological principles and the development of brain-machine interfaces (BMIs). Here we describe a neurophysiological paradigm for performing tethered and wireless large-scale recordings based on movable volumetric three-dimensional (3D) multielectrode implants. This approach allowed us to isolate up to 1,800 units per animal and simultaneously record the extracellular activity of close to 500 cortical neurons, distributed across multiple cortical areas, in freely behaving rhesus monkeys. The method is expandable, in principle, to thousands of simultaneously recorded channels. It also allows increased recording longevity (5 consecutive years), and recording of a broad range of behaviors, e.g. social interactions, and BMI paradigms in freely moving primates. We propose that wireless large-scale recordings could have a profound impact on basic primate neurophysiology research, while providing a framework for the development and testing of clinically relevant neuroprostheses. PMID:24776634

Greater screen time is associated with adolescent obesity: a longitudinal study of the BMI distribution from Ages 14 to 18.

PubMed

Mitchell, Jonathan A; Rodriguez, Daniel; Schmitz, Kathryn H; Audrain-McGovern, Janet

2013-03-01

Previous research has examined the association between screen time and average changes in adolescent body mass index (BMI). Until now, no study has evaluated the longitudinal relationship between screen time and changes in the BMI distribution across mid to late adolescence. Participants (n = 1,336) were adolescents who were followed from age 14 to age 18 and surveyed every 6 months. Time spent watching television/videos and playing video games was self-reported (<1 h day(-1) , 1 h day(-1) , 2 h day(-1) , 3 h day(-1) , 4 h day(-1) , or 5+ h day(-1) ). BMI (kg m(-2) ) was calculated from self-reported height and weight. Longitudinal quantile regression was used to model the 10th, 25th, 50th, 75th, and 90th BMI percentiles as dependent variables. Study wave and screen time were the main predictors, and adjustment was made for gender, race, maternal education, hours of sleep, and physical activity. Increases at all the BMI percentiles over time were observed, with the greatest increase observed at the 90th BMI percentile. Screen time was positively associated with changes in BMI at the 50th (0.17, 95% CI: 0.06, 0.27), 75th (0.31, 95% CI: 0.10, 0.52), and 90th BMI percentiles (0.56, 95% CI: 0.27, 0.82). No associations were observed between screen time and changes at the 10th and 25th BMI percentiles. Positive associations between screen time and changes in the BMI at the upper tail of the BMI distribution were observed. Therefore, lowering screen time, especially among overweight and obese adolescents, could contribute to reducing the prevalence of adolescent obesity. Copyright © 2013 The Obesity Society.

Prediction of movement intention using connectivity within motor-related network: An electrocorticography study.

PubMed

Kang, Byeong Keun; Kim, June Sic; Ryun, Seokyun; Chung, Chun Kee

2018-01-01

Most brain-machine interface (BMI) studies have focused only on the active state of which a BMI user performs specific movement tasks. Therefore, models developed for predicting movements were optimized only for the active state. The models may not be suitable in the idle state during resting. This potential maladaptation could lead to a sudden accident or unintended movement resulting from prediction error. Prediction of movement intention is important to develop a more efficient and reasonable BMI system which could be selectively operated depending on the user's intention. Physical movement is performed through the serial change of brain states: idle, planning, execution, and recovery. The motor networks in the primary motor cortex and the dorsolateral prefrontal cortex are involved in these movement states. Neuronal communication differs between the states. Therefore, connectivity may change depending on the states. In this study, we investigated the temporal dynamics of connectivity in dorsolateral prefrontal cortex and primary motor cortex to predict movement intention. Movement intention was successfully predicted by connectivity dynamics which may reflect changes in movement states. Furthermore, dorsolateral prefrontal cortex is crucial in predicting movement intention to which primary motor cortex contributes. These results suggest that brain connectivity is an excellent approach in predicting movement intention.

A Context-Aware EEG Headset System for Early Detection of Driver Drowsiness.

PubMed

Li, Gang; Chung, Wan-Young

2015-08-21

Driver drowsiness is a major cause of mortality in traffic accidents worldwide. Electroencephalographic (EEG) signal, which reflects the brain activities, is more directly related to drowsiness. Thus, many Brain-Machine-Interface (BMI) systems have been proposed to detect driver drowsiness. However, detecting driver drowsiness at its early stage poses a major practical hurdle when using existing BMI systems. This study proposes a context-aware BMI system aimed to detect driver drowsiness at its early stage by enriching the EEG data with the intensity of head-movements. The proposed system is carefully designed for low-power consumption with on-chip feature extraction and low energy Bluetooth connection. Also, the proposed system is implemented using JAVA programming language as a mobile application for on-line analysis. In total, 266 datasets obtained from six subjects who participated in a one-hour monotonous driving simulation experiment were used to evaluate this system. According to a video-based reference, the proposed system obtained an overall detection accuracy of 82.71% for classifying alert and slightly drowsy events by using EEG data alone and 96.24% by using the hybrid data of head-movement and EEG. These results indicate that the combination of EEG data and head-movement contextual information constitutes a robust solution for the early detection of driver drowsiness.

A Context-Aware EEG Headset System for Early Detection of Driver Drowsiness

PubMed Central

Li, Gang; Chung, Wan-Young

2015-01-01

Driver drowsiness is a major cause of mortality in traffic accidents worldwide. Electroencephalographic (EEG) signal, which reflects the brain activities, is more directly related to drowsiness. Thus, many Brain-Machine-Interface (BMI) systems have been proposed to detect driver drowsiness. However, detecting driver drowsiness at its early stage poses a major practical hurdle when using existing BMI systems. This study proposes a context-aware BMI system aimed to detect driver drowsiness at its early stage by enriching the EEG data with the intensity of head-movements. The proposed system is carefully designed for low-power consumption with on-chip feature extraction and low energy Bluetooth connection. Also, the proposed system is implemented using JAVA programming language as a mobile application for on-line analysis. In total, 266 datasets obtained from six subjects who participated in a one-hour monotonous driving simulation experiment were used to evaluate this system. According to a video-based reference, the proposed system obtained an overall detection accuracy of 82.71% for classifying alert and slightly drowsy events by using EEG data alone and 96.24% by using the hybrid data of head-movement and EEG. These results indicate that the combination of EEG data and head-movement contextual information constitutes a robust solution for the early detection of driver drowsiness. PMID:26308002

The role of motivation in family-based guided self-help treatment for pediatric obesity.

PubMed

Accurso, Erin C; Norman, Gregory J; Crow, Scott J; Rock, Cheryl L; Boutelle, Kerri N

2014-10-01

Identifying factors associated with effective treatment for childhood obesity is important to improving weight loss outcomes. The current study investigated whether child or parent motivation throughout the course of treatment predicted reductions in BMI. Fifty 8- to 12-year-old children with overweight and obesity (BMI percentiles 85-98%) and their parents participated in a guided self-help weight loss program, which included 12 brief sessions across 5 months. Parents and interventionists reported on child and parent motivation level at each session. Multilevel slopes-as-outcome models were used to examine growth trajectories for both child and parent BMI across sessions. Greater interventionist-rated child motivation predicted greater reductions in child BMI; parent motivation did not. However, interventionist-rated parent motivation predicted greater reductions in parent BMI, and its impact on BMI became more pronounced over the course of treatment, such that sustained motivation was more important than initial motivation. Children who were older, Latino, or who had lower initial BMIs had slower reductions in BMI. This study suggests that motivation may be an important predictor of reduced BMI in child obesity treatment, with sustained motivation being more important than initial motivation. In particular, interventionist-rated, but not parent-rated, motivation is a robust predictor of child and parent BMI outcomes. Future research may evaluate whether motivational interventions can enhance outcome, with particular attention to improving outcomes for Latino children.

Quantification of normative ranges and baseline predictors of aortoventricular interface dimensions using multi-detector computed tomographic imaging in patients without aortic valve disease.

PubMed

Gooley, Robert P; Cameron, James D; Soon, Jennifer; Loi, Duncan; Chitale, Gauri; Syeda, Rifath; Meredith, Ian T

2015-09-01

Multidetector computed tomographic (MDCT) assessment of the aortoventricular interface has gained increased importance with the advent of minimally invasive treatment modalities for aortic and mitral valve disease. This has included a standardised technique of identifying a plane through the nadir of each coronary cusp, the basal plane, and taking further measurements in relation to this plane. Despite this there is no published data defining normal ranges for these aortoventricular metrics in a healthy cohort. This study seeks to quantify normative ranges for MDCT derived aortoventricular dimensions and evaluate baseline demographic and anthropomorphic associates of these measurements in a normal cohort. 250 consecutive patients undergoing MDCT coronary angiography were included. Aortoventricular dimensions at multiple levels of the aortoventricular interface were assessed and normative ranges quantified. Multivariate linear regression was performed to identify baseline predictors of each metric. The mean age was 59±12 years. The basal plane was eccentric (EI=0.22±0.06) while the left ventricular outflow tract was more eccentric (EI=0.32±0.06), with no correlation to gender, age or hypertension. Male gender, height and body mass index were consistent independent predictors of larger aortoventricular dimensions at all anatomical levels, while age was predictive of supra-annular measurements. Male gender, height and BMI are independent predictors of all aortoventricular dimensions while age predicts only supra-annular dimensions. Use of defined metrics such as the basal plane and formation of normative ranges for these metrics allows reference for clinical reporting and for future research studies by using a standardised measurement technique. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Model validation of untethered, ultrasonic neural dust motes for cortical recording.

PubMed

Seo, Dongjin; Carmena, Jose M; Rabaey, Jan M; Maharbiz, Michel M; Alon, Elad

2015-04-15

A major hurdle in brain-machine interfaces (BMI) is the lack of an implantable neural interface system that remains viable for a substantial fraction of the user's lifetime. Recently, sub-mm implantable, wireless electromagnetic (EM) neural interfaces have been demonstrated in an effort to extend system longevity. However, EM systems do not scale down in size well due to the severe inefficiency of coupling radio-waves at those scales within tissue. This paper explores fundamental system design trade-offs as well as size, power, and bandwidth scaling limits of neural recording systems built from low-power electronics coupled with ultrasonic power delivery and backscatter communication. Such systems will require two fundamental technology innovations: (1) 10-100 μm scale, free-floating, independent sensor nodes, or neural dust, that detect and report local extracellular electrophysiological data via ultrasonic backscattering and (2) a sub-cranial ultrasonic interrogator that establishes power and communication links with the neural dust. We provide experimental verification that the predicted scaling effects follow theory; (127 μm)(3) neural dust motes immersed in water 3 cm from the interrogator couple with 0.002064% power transfer efficiency and 0.04246 ppm backscatter, resulting in a maximum received power of ∼0.5 μW with ∼1 nW of change in backscatter power with neural activity. The high efficiency of ultrasonic transmission can enable the scaling of the sensing nodes down to 10s of micrometer. We conclude with a brief discussion of the application of neural dust for both central and peripheral nervous system recordings, and perspectives on future research directions. Copyright © 2014 Elsevier B.V. All rights reserved.

Childhood Obesity: An Overview

ERIC Educational Resources Information Center

Reilly, John J.

2007-01-01

This article reviews recent research evidence, largely from systematic reviews, on a number of aspects of childhood obesity: its definition and prevalence; consequences; causes and prevention. The basis of the body mass index (BMI) as a means of defining obesity in children and adolescents is discussed: a high BMI for age constitutes obesity. In…

Genetic Risk Score Mendelian Randomization Shows that Obesity Measured as Body Mass Index, but not Waist:Hip Ratio, Is Causal for Endometrial Cancer.

PubMed

Painter, Jodie N; O'Mara, Tracy A; Marquart, Louise; Webb, Penelope M; Attia, John; Medland, Sarah E; Cheng, Timothy; Dennis, Joe; Holliday, Elizabeth G; McEvoy, Mark; Scott, Rodney J; Ahmed, Shahana; Healey, Catherine S; Shah, Mitul; Gorman, Maggie; Martin, Lynn; Hodgson, Shirley V; Beckmann, Matthias W; Ekici, Arif B; Fasching, Peter A; Hein, Alexander; Rübner, Matthias; Czene, Kamila; Darabi, Hatef; Hall, Per; Li, Jingmei; Dörk, Thilo; Dürst, Matthias; Hillemanns, Peter; Runnebaum, Ingo B; Amant, Frederic; Annibali, Daniela; Depreeuw, Jeroen; Lambrechts, Diether; Neven, Patrick; Cunningham, Julie M; Dowdy, Sean C; Goode, Ellen L; Fridley, Brooke L; Winham, Stacey J; Njølstad, Tormund S; Salvesen, Helga B; Trovik, Jone; Werner, Henrica M J; Ashton, Katie A; Otton, Geoffrey; Proietto, Anthony; Mints, Miriam; Tham, Emma; Bolla, Manjeet K; Michailidou, Kyriaki; Wang, Qin; Tyrer, Jonathan P; Hopper, John L; Peto, Julian; Swerdlow, Anthony J; Burwinkel, Barbara; Brenner, Hermann; Meindl, Alfons; Brauch, Hiltrud; Lindblom, Annika; Chang-Claude, Jenny; Couch, Fergus J; Giles, Graham G; Kristensen, Vessela N; Cox, Angela; Pharoah, Paul D P; Tomlinson, Ian; Dunning, Alison M; Easton, Douglas F; Thompson, Deborah J; Spurdle, Amanda B

2016-11-01

The strongest known risk factor for endometrial cancer is obesity. To determine whether SNPs associated with increased body mass index (BMI) or waist-hip ratio (WHR) are associated with endometrial cancer risk, independent of measured BMI, we investigated relationships between 77 BMI and 47 WHR SNPs and endometrial cancer in 6,609 cases and 37,926 country-matched controls. Logistic regression analysis and fixed effects meta-analysis were used to test for associations between endometrial cancer risk and (i) individual BMI or WHR SNPs, (ii) a combined weighted genetic risk score (wGRS) for BMI or WHR. Causality of BMI for endometrial cancer was assessed using Mendelian randomization, with BMIwGRS as instrumental variable. The BMIwGRS was significantly associated with endometrial cancer risk (P = 3.4 × 10 -17 ). Scaling the effect of the BMIwGRS on endometrial cancer risk by its effect on BMI, the endometrial cancer OR per 5 kg/m 2 of genetically predicted BMI was 2.06 [95% confidence interval (CI), 1.89-2.21], larger than the observed effect of BMI on endometrial cancer risk (OR = 1.55; 95% CI, 1.44-1.68, per 5 kg/m 2 ). The association attenuated but remained significant after adjusting for BMI (OR = 1.22; 95% CI, 1.10-1.39; P = 5.3 × 10 -4 ). There was evidence of directional pleiotropy (P = 1.5 × 10 -4 ). BMI SNP rs2075650 was associated with endometrial cancer at study-wide significance (P < 4.0 × 10 -4 ), independent of BMI. Endometrial cancer was not significantly associated with individual WHR SNPs or the WHRwGRS. BMI, but not WHR, is causally associated with endometrial cancer risk, with evidence that some BMI-associated SNPs alter endometrial cancer risk via mechanisms other than measurable BMI. The causal association between BMI SNPs and endometrial cancer has possible implications for endometrial cancer risk modeling. Cancer Epidemiol Biomarkers Prev; 25(11); 1503-10. ©2016 AACR. ©2016 American Association for Cancer Research.

High Body Mass Index Is an Indicator of Maternal Hypothyroidism, Hypothyroxinemia, and Thyroid-Peroxidase Antibody Positivity during Early Pregnancy

PubMed Central

Han, Cheng; Li, Chenyan; Mao, Jinyuan; Wang, Weiwei; Xie, Xiaochen; Zhou, Weiwei; Li, Chenyang; Xu, Bin; Bi, Lihua; Meng, Tao; Du, Jianling; Zhang, Shaowei; Gao, Zhengnan; Zhang, Xiaomei; Yang, Liu; Fan, Chenling; Teng, Weiping; Shan, Zhongyan

2015-01-01

Background. Maternal thyroid dysfunction in early pregnancy may increase the risk of adverse pregnancy complications and neurocognitive deficiencies in the developing fetus. Currently, some researchers demonstrated that body mass index (BMI) is associated with thyroid function in nonpregnant population. Hence, the American Thyroid Association recommended screening thyroid function in obese pregnant women; however, the evidence for this is weak. For this purpose, our study investigated the relationship between high BMI and thyroid functions during early pregnancy in Liaoning province, an iodine-sufficient region of China. Methods. Serum thyroid stimulating hormone (TSH), free thyroxine (FT4), thyroid-peroxidase antibody (TPOAb), thyroglobulin antibody (TgAb) concentration, urinary iodine concentration (UIC), and BMI were determined in 6303 pregnant women. Results. BMI ≥ 25 kg/m2 may act as an indicator of hypothyroxinemia and TPOAb positivity and BMI ≥ 30 kg/m2 was associated with increases in the odds of hypothyroidism, hypothyroxinemia, and TPOAb positivity. The prevalence of isolated hypothyroxinemia increased among pregnant women with BMI > 24 kg/m2. Conclusions. High BMI during early pregnancy may be an indicator of maternal thyroid dysfunction; for Asian women whose BMI > 24 kg/m2 and who are within 8 weeks of pregnancy, thyroid functions should be assessed especially. PMID:26273610

The association between body mass index and physical activity, and body image, self esteem and social support in adolescents with type 1 diabetes.

PubMed

Kaminsky, Laura A; Dewey, Deborah

2014-08-01

To examine the associations between body mass index (BMI) and physical activity with body image, self-esteem and social support in adolescents with type 1 diabetes compared to adolescents without health conditions. We studied 46 adolescents with type 1 diabetes and 27 comparison adolescents who provided self-reports of height and weight, which were used to calculate BMI z-scores. Participants also completed validated questionnaires that assessed physical activity, body image, self-esteem and social support. No significant group differences were found between adolescents with type 1 diabetes and comparison adolescents in terms of BMI and physical activity. Examination of group and gender revealed that higher BMI was significantly associated with a less positive body image in girls with diabetes only. Higher BMI was associated with poorer self-esteem and lower levels of social support in adolescents with diabetes, particularly girls. Higher levels of physical activity were not associated with a more positive body image and no significant associations were found between physical activity and self-esteem or social support. BMI and physical activity levels of adolescents with type 1 diabetes do not differ from those of adolescents without diabetes. Higher BMI is associated with a less positive body image and poorer psychosocial outcomes, particularly in girls with diabetes. As body image concerns and various psychosocial factors could be precursors to the development of eating-disorder symptoms, future research in adolescents with diabetes with higher BMIs should examine the associations among these variables. Further, it is essential that research on body image take into account gender differences. Copyright © 2014 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

Differential Efficacy of Nicotine Replacement Among Overweight and Obese Women Smokers.

PubMed

Strong, David R; David, Sean P; Johnstone, Elaine C; Aveyard, Paul; Murphy, Michael F; Munafò, Marcus R

2015-07-01

Rates of obesity are higher among more dependent smokers and 37%-65% of smokers seeking cessation treatment are overweight or obese. Overweight or obese smokers may possess metabolic and neurobiological features that contribute to difficulty achieving cessation using front-line nicotine replacement products. Attention to factors that facilitate effective cessation treatment in this vulnerable population is needed to significantly reduce mortality risk among overweight and obese smokers. This secondary analysis of 2 large trials of transdermal nicotine replacement in general medical practices evaluated the hypothesis that higher body mass index (BMI) would moderate the efficacy of the nicotine patch. We examined the potential for gender to further moderate the relationship between BMI and treatment efficacy. In the placebo controlled trial (N = 1,621), 21-mg patch was no more effective than placebo for assisting biochemically verified point prevalence abstinence up to 1 year after quitting for women with higher BMI, but appeared to be effective for men at normal or high BMI (gender × BMI beta = -0.22, p = .004). We did not find differential long-term cessation outcomes among male or female smokers in the 15-mg patch trial (n = 705). However, we observed significantly higher rates of early lapse among women with higher BMI treated with nicotine patch across both trials. These results suggest that increased BMI may affect the efficacy of nicotine patch on reducing risk of early lapse in women. Additional research is needed to explore mechanisms of risk for decreased efficacy of this commonly used cessation aid. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Towards real-time communication between in vivo neurophysiological data sources and simulator-based brain biomimetic models.

PubMed

Lee, Giljae; Matsunaga, Andréa; Dura-Bernal, Salvador; Zhang, Wenjie; Lytton, William W; Francis, Joseph T; Fortes, José Ab

2014-11-01

Development of more sophisticated implantable brain-machine interface (BMI) will require both interpretation of the neurophysiological data being measured and subsequent determination of signals to be delivered back to the brain. Computational models are the heart of the machine of BMI and therefore an essential tool in both of these processes. One approach is to utilize brain biomimetic models (BMMs) to develop and instantiate these algorithms. These then must be connected as hybrid systems in order to interface the BMM with in vivo data acquisition devices and prosthetic devices. The combined system then provides a test bed for neuroprosthetic rehabilitative solutions and medical devices for the repair and enhancement of damaged brain. We propose here a computer network-based design for this purpose, detailing its internal modules and data flows. We describe a prototype implementation of the design, enabling interaction between the Plexon Multichannel Acquisition Processor (MAP) server, a commercial tool to collect signals from microelectrodes implanted in a live subject and a BMM, a NEURON-based model of sensorimotor cortex capable of controlling a virtual arm. The prototype implementation supports an online mode for real-time simulations, as well as an offline mode for data analysis and simulations without real-time constraints, and provides binning operations to discretize continuous input to the BMM and filtering operations for dealing with noise. Evaluation demonstrated that the implementation successfully delivered monkey spiking activity to the BMM through LAN environments, respecting real-time constraints.

Design and validation of a real-time spiking-neural-network decoder for brain-machine interfaces.

PubMed

Dethier, Julie; Nuyujukian, Paul; Ryu, Stephen I; Shenoy, Krishna V; Boahen, Kwabena

2013-06-01

Cortically-controlled motor prostheses aim to restore functions lost to neurological disease and injury. Several proof of concept demonstrations have shown encouraging results, but barriers to clinical translation still remain. In particular, intracortical prostheses must satisfy stringent power dissipation constraints so as not to damage cortex. One possible solution is to use ultra-low power neuromorphic chips to decode neural signals for these intracortical implants. The first step is to explore in simulation the feasibility of translating decoding algorithms for brain-machine interface (BMI) applications into spiking neural networks (SNNs). Here we demonstrate the validity of the approach by implementing an existing Kalman-filter-based decoder in a simulated SNN using the Neural Engineering Framework (NEF), a general method for mapping control algorithms onto SNNs. To measure this system's robustness and generalization, we tested it online in closed-loop BMI experiments with two rhesus monkeys. Across both monkeys, a Kalman filter implemented using a 2000-neuron SNN has comparable performance to that of a Kalman filter implemented using standard floating point techniques. These results demonstrate the tractability of SNN implementations of statistical signal processing algorithms on different monkeys and for several tasks, suggesting that a SNN decoder, implemented on a neuromorphic chip, may be a feasible computational platform for low-power fully-implanted prostheses. The validation of this closed-loop decoder system and the demonstration of its robustness and generalization hold promise for SNN implementations on an ultra-low power neuromorphic chip using the NEF.

Are BMI and Sedentariness Correlated? A Multilevel Study in Children

PubMed Central

Gomes, Thayse Natacha; Katzmarzyk, Peter T.; dos Santos, Fernanda Karina; de Chaves, Raquel Nichele; Santos, Daniel; Pereira, Sara; Champagne, Catherine M.; Hedeker, Donald; Maia, José

2015-01-01

The purpose of this research was to investigate the relationship between body mass index (BMI) and sedentariness (Sed) in children and to examine the influence of child and school correlates on their variation. The sample comprises 580 children (337 girls, 9–11 years). Sedentariness was assessed with an accelerometer, and BMI was computed. Child- and school-level covariates were analyzed using multilevel models. No significant correlation between Sed and BMI was found. School context explains 5% and 1.5% of the total variance in Sed and BMI, respectively. At the child level, only moderate-to-vigorous physical activity was associated with both Sed (β = −0.02 ± 0.002) and BMI (β = −0.005 ± 0.002). Sleep time is related to Sed (β = −0.42 ± 0.04), while sex (β = 1.97 ± 0.13), biological maturity (β = 1.25 ± 0.07), media in the bedroom (β = 0.26 ± 0.08) and healthy (β = −0.09 ± 0.03) and unhealthy (β = −0.07 ± 0.04) diet scores were associated with BMI. None of the school-level covariates were related to BMI, but access to cafeteria (β = −0.97 ± 0.25), playground equipment (β = −0.67 ± 0.20) and restaurants (β = 0.16 ± 0.08) were related to Sed. In conclusion, Sed and BMI were not correlated. Further, they have different correlates, while children’s traits seem to play more relevant roles in their differences in Sed and BMI than the school milieu. This information should be taken into account when strategies to reduce Sed and BMI are implemented. PMID:26193311

Body mass index and economic productivity.

PubMed

Kennedy, E; Garcia, M

1994-11-01

The paper reviews the evidence to date on the nutritional links with productivity and then goes on to provide results from a multi-country study on the effects of increasing body mass index (BMI) on productivity. The research relating nutritional status to work capacity is more consistent than the research linking nutritional status to productivity. None of the studies to date elucidate the pathways through which improved nutrition improves economic productivity. In addition, many of the studies that have been conducted on the nutrition/wage links have been based on samples that contained a disproportionate number of male subjects. The few studies that have disaggregated data by gender report different results for men and women. Research conducted at IFPRI is presented to examine the trends in BMI for men and women across countries and for Kenya to examine the relationships between various measures of nutritional status--BMI and height--and energy expenditures in women. BMIs of men show a more consistent relationship with increasing household income than do the BMIs of women. In the case of the Gambia and Kenya, the mean BMI of women decreases with increasing household income. One reason for the apparently low response of BMI to increasing household income in Kenya is the time allocation patterns of women. Women in the Kenya sample spend the largest proportion of their day in home production activities which are energy intensive. In examining the relationship between nutritional indicators and the time devoted to work, the results suggest a significant, positive association between both BMI and height and the amount of time devoted to work. In the models presented, both BMI and height appear to increase the capacity to carry out work. It is difficult to value much of this work time since a disproportionate share is devoted to home production activities. Some of the more classic methods of measuring economic productivity, such as measuring wage rates, are not relevant for women in this setting. The data from Kenya suggest that more appropriate measures for specifying the value of women's work need to be developed in order to capture some of the nutrition/productivity links which may exist.

The Use of Arm Span as a Substitute for Height in Calculating Body Mass Index (BMI) for Spine Deformity Patients.

PubMed

Opoku, Harriet; Yirerong, Theresa; Osei-Onwona, Belinda; Boachie-Adjei, Oheneba

To compare arm span and height in body mass index (BMI) calculation in patients with spinal curvature and investigate their impact on interpretation of BMI. Prospective case-control cohorts. The BMI value is based on weight to height ratio. Spine deformity patients experience height loss and its use in calculating BMI is likely to produce errors. A surrogate for height should therefore be sought in BMI determination. Ninety-three spine deformity patients were matched with 64 normal children. Anthropometric values (height, arm span, and weight) and spinal curve were obtained. BMIs using arm span and height were calculated, and statistical analysis performed to assess the relationship between BMI/height and BMI/arm span in both groups as well as the relationship between these values and Arm Span to Height difference (Delta AH). There were 46 males and 47 females, the average age was 15.5 years in Group 1 versus 33 males and 31 females, average age 14.8 years in Group 2. Major scoliosis in Group 1 averaged 125.7° (21° to 252°). The extreme curves show vertebral transposition, with overlapping segments making it more than 180°. A logistic regression showed that there was linearity in BMI scores (R 2 = 0.97) for both arm span and height (R 2 = 0.94) in group 2 patients. For group 1 patients there was a significant difference in the BMI values when comparing BMI/arm span versus BMI/height (p < .0001). Mean BMI values using height was overstated by 2.8 (18.6%). The threshold at which BMI score must be calculated using arm span as opposed to the height (Delta AH) was determined to be 3 cm. Spine deformity patients experience height loss, which can impact their true BMI values thereby giving an erroneous impression of their nutritional status. The arm span should be used in patients with Delta AH >3 cm to properly assess nutritional status. Copyright © 2017 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.

Bidirectional associations between mothers' and fathers' parenting consistency and child BMI.

PubMed

Jansen, Pauline W; Giallo, Rebecca; Westrupp, Elizabeth M; Wake, Melissa; Nicholson, Jan M

2013-12-01

Research suggests that general parenting dimensions and styles are associated with children's BMI, but directionality in this relationship remains unknown. Moreover, there has been little attention to the influences of both mothers' and fathers' parenting. We aimed to examine reciprocal relationships between maternal and paternal parenting consistency and child BMI. Participants were 4002 children and their parents in the population-based Longitudinal Study of Australian Children. Mothers and fathers self-reported parenting consistency, and children's BMI was measured at 4 biennial waves starting at age 4 to 5 years in 2004. Bidirectionality between parenting and child BMI was examined by using regression analyses in cross-lagged models. The best-fitting models indicated a modest influence from parenting to child BMI, whereas no support was found for bidirectional influences. For mothers, higher levels of parenting consistency predicted lower BMI in children from Waves 1 to 2 and 3 to 4; for example, for every SD increase in mothers' parenting consistency at Wave 1, child BMIz fell by 0.025 in Wave 2 (95% confidence interval: -0.05 to -0.003). For fathers, higher levels of parenting consistency were associated with lower child BMI from Waves 1 to 2 and 2 to 3. Parenting inconsistency of mothers and fathers prospectively predicted small increases in offspring BMI over 2-year periods across middle childhood. However, child BMI did not appear to influence parenting behavior. These findings support recent calls for expanding childhood overweight interventions to address the broad parenting context while involving both mothers and fathers.

Predictors of outcomes in outpatients with anorexia nervosa - Results from the ANTOP study.

PubMed

Wild, Beate; Friederich, Hans-Christoph; Zipfel, Stephan; Resmark, Gaby; Giel, Katrin; Teufel, Martin; Schellberg, Dieter; Löwe, Bernd; de Zwaan, Martina; Zeeck, Almut; Herpertz, Stephan; Burgmer, Markus; von Wietersheim, Jörn; Tagay, Sefik; Dinkel, Andreas; Herzog, Wolfgang

2016-10-30

This study aimed to determine predictors of BMI and recovery for outpatients with anorexia nervosa (AN). Patients were participants of the ANTOP (Anorexia Nervosa Treatment of Out-Patients) trial and randomized to focal psychodynamic therapy (FPT), enhanced cognitive behavior therapy (CBT-E), or optimized treatment as usual (TAU-O). N=169 patients participated in the one-year follow-up (T4). Outcomes were the BMI and global outcome (recovery/partial syndrome/full syndrome) at T4. We examined the following baseline variables as possible predictors: age, BMI, duration of illness, subtype of AN, various axis I diagnoses, quality of life, self-esteem, and psychological characteristics relevant to AN. Linear and logistic regression analyses were conducted to identify the predictors of the BMI and global outcome. The strongest positive predictor for BMI and recovery at T4 was a higher baseline BMI of the patients. Negative predictors for BMI and recovery were a duration of illness >6 years and a lifetime depression diagnosis at baseline. Additionally, higher bodily pain was significantly associated with a lower BMI and self-esteem was a positive predictor for recovery at T4. A higher baseline BMI and shorter illness duration led to a better outcome. Further research is necessary to investigate whether or not AN patients with lifetime depression, higher bodily pain, and lower self-esteem may benefit from specific treatment approaches. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The Role of Motivation in Family-Based Guided Self-Help Treatment for Pediatric Obesity

PubMed Central

Norman, Gregory J.; Crow, Scott J.; Rock, Cheryl L.; Boutelle, Kerri N.

2014-01-01

Abstract Background: Identifying factors associated with effective treatment for childhood obesity is important to improving weight loss outcomes. The current study investigated whether child or parent motivation throughout the course of treatment predicted reductions in BMI. Methods: Fifty 8- to 12-year-old children with overweight and obesity (BMI percentiles 85–98%) and their parents participated in a guided self-help weight loss program, which included 12 brief sessions across 5 months. Parents and interventionists reported on child and parent motivation level at each session. Multilevel slopes-as-outcome models were used to examine growth trajectories for both child and parent BMI across sessions. Results: Greater interventionist-rated child motivation predicted greater reductions in child BMI; parent motivation did not. However, interventionist-rated parent motivation predicted greater reductions in parent BMI, and its impact on BMI became more pronounced over the course of treatment, such that sustained motivation was more important than initial motivation. Children who were older, Latino, or who had lower initial BMIs had slower reductions in BMI. Conclusions: This study suggests that motivation may be an important predictor of reduced BMI in child obesity treatment, with sustained motivation being more important than initial motivation. In particular, interventionist-rated, but not parent-rated, motivation is a robust predictor of child and parent BMI outcomes. Future research may evaluate whether motivational interventions can enhance outcome, with particular attention to improving outcomes for Latino children. PMID:25181608

Humanlike robot hands controlled by brain activity arouse illusion of ownership in operators

PubMed Central

Alimardani, Maryam; Nishio, Shuichi; Ishiguro, Hiroshi

2013-01-01

Operators of a pair of robotic hands report ownership for those hands when they hold image of a grasp motion and watch the robot perform it. We present a novel body ownership illusion that is induced by merely watching and controlling robot's motions through a brain machine interface. In past studies, body ownership illusions were induced by correlation of such sensory inputs as vision, touch and proprioception. However, in the presented illusion none of the mentioned sensations are integrated except vision. Our results show that during BMI-operation of robotic hands, the interaction between motor commands and visual feedback of the intended motions is adequate to incorporate the non-body limbs into one's own body. Our discussion focuses on the role of proprioceptive information in the mechanism of agency-driven illusions. We believe that our findings will contribute to improvement of tele-presence systems in which operators incorporate BMI-operated robots into their body representations. PMID:23928891

Smart Frameworks and Self-Describing Models: Model Metadata for Automated Coupling of Hydrologic Process Components (Invited)

NASA Astrophysics Data System (ADS)

Peckham, S. D.

2013-12-01

Model coupling frameworks like CSDMS (Community Surface Dynamics Modeling System) and ESMF (Earth System Modeling Framework) have developed mechanisms that allow heterogeneous sets of process models to be assembled in a plug-and-play manner to create composite "system models". These mechanisms facilitate code reuse, but must simultaneously satisfy many different design criteria. They must be able to mediate or compensate for differences between the process models, such as their different programming languages, computational grids, time-stepping schemes, variable names and variable units. However, they must achieve this interoperability in a way that: (1) is noninvasive, requiring only relatively small and isolated changes to the original source code, (2) does not significantly reduce performance, (3) is not time-consuming or confusing for a model developer to implement, (4) can very easily be updated to accommodate new versions of a given process model and (5) does not shift the burden of providing model interoperability to the model developers, e.g. by requiring them to provide their output in specific forms that meet the input requirements of other models. In tackling these design challenges, model framework developers have learned that the best solution is to provide each model with a simple, standardized interface, i.e. a set of standardized functions that make the model: (1) fully-controllable by a caller (e.g. a model framework) and (2) self-describing. Model control functions are separate functions that allow a caller to initialize the model, advance the model's state variables in time and finalize the model. Model description functions allow a caller to retrieve detailed information on the model's input and output variables, its computational grid and its timestepping scheme. If the caller is a modeling framework, it can compare the answers to these queries with similar answers from other process models in a collection and then automatically call framework service components as necessary to mediate the differences between the coupled models. This talk will first review two key products of the CSDMS project, namely a standardized model interface called the Basic Model Interface (BMI) and the CSDMS Standard Names. The standard names are used in conjunction with BMI to provide a semantic matching mechanism that allows output variables from one process model to be reliably used as input variables to other process models in a collection. They include not just a standardized naming scheme for model variables, but also a standardized set of terms for describing the attributes and assumptions of a given model. To illustrate the power of standardized model interfaces and metadata, a smart, light-weight modeling framework written in Python will be introduced that can automatically (without user intervention) couple a set of BMI-enabled hydrologic process components together to create a spatial hydrologic model. The same mechanisms could also be used to provide seamless integration (import/export) of data and models.

A Wireless 32-Channel Implantable Bidirectional Brain Machine Interface

PubMed Central

Su, Yi; Routhu, Sudhamayee; Moon, Kee S.; Lee, Sung Q.; Youm, WooSub; Ozturk, Yusuf

2016-01-01

All neural information systems (NIS) rely on sensing neural activity to supply commands and control signals for computers, machines and a variety of prosthetic devices. Invasive systems achieve a high signal-to-noise ratio (SNR) by eliminating the volume conduction problems caused by tissue and bone. An implantable brain machine interface (BMI) using intracortical electrodes provides excellent detection of a broad range of frequency oscillatory activities through the placement of a sensor in direct contact with cortex. This paper introduces a compact-sized implantable wireless 32-channel bidirectional brain machine interface (BBMI) to be used with freely-moving primates. The system is designed to monitor brain sensorimotor rhythms and present current stimuli with a configurable duration, frequency and amplitude in real time to the brain based on the brain activity report. The battery is charged via a novel ultrasonic wireless power delivery module developed for efficient delivery of power into a deeply-implanted system. The system was successfully tested through bench tests and in vivo tests on a behaving primate to record the local field potential (LFP) oscillation and stimulate the target area at the same time. PMID:27669264

Physiological properties of brain-machine interface input signals.

PubMed

Slutzky, Marc W; Flint, Robert D

2017-08-01

Brain-machine interfaces (BMIs), also called brain-computer interfaces (BCIs), decode neural signals and use them to control some type of external device. Despite many experimental successes and terrific demonstrations in animals and humans, a high-performance, clinically viable device has not yet been developed for widespread usage. There are many factors that impact clinical viability and BMI performance. Arguably, the first of these is the selection of brain signals used to control BMIs. In this review, we summarize the physiological characteristics and performance-including movement-related information, longevity, and stability-of multiple types of input signals that have been used in invasive BMIs to date. These include intracortical spikes as well as field potentials obtained inside the cortex, at the surface of the cortex (electrocorticography), and at the surface of the dura mater (epidural signals). We also discuss the potential for future enhancements in input signal performance, both by improving hardware and by leveraging the knowledge of the physiological characteristics of these signals to improve decoding and stability. Copyright © 2017 the American Physiological Society.

Stand-Biased Versus Seated Classrooms and Childhood Obesity: A Randomized Experiment in Texas

PubMed Central

Wendel, Monica L.; Zhao, Hongwei; Jeffrey, Christina

2016-01-01

Objectives. To measure changes in body mass index (BMI) percentiles among third- and fourth-grade students in stand-biased classrooms and traditional seated classrooms in 3 Texas elementary schools. Methods. Research staff recorded the height and weight of 380 students in 24 classrooms across the 3 schools at the beginning (2011–2012) and end (2012–2013) of the 2-year study. Results. After adjustment for grade, race/ethnicity, and gender, there was a statistically significant decrease in BMI percentile in the group that used stand-biased desks for 2 consecutive years relative to the group that used standard desks during both years. Mean BMI increased by 0.1 and 0.4 kilograms per meter squared in the treatment and control groups, respectively. The between-group difference in BMI percentile change was 5.24 (SE = 2.50; P = .037). No other covariates had a statistically significant impact on BMI percentile changes. Conclusions. Changing a classroom to a stand-biased environment had a significant effect on students’ BMI percentile, indicating the need to redesign traditional classroom environments. PMID:27552276

Why are there race/ethnic differences in adult body mass index–adiposity relationships? A quantitative critical review

PubMed Central

Heymsfield, S. B.; Peterson, C. M.; Thomas, D. M.; Heo, M.; Schuna, J. M.

2016-01-01

Summary Body mass index (BMI) is now the most widely used measure of adiposity on a global scale. Nevertheless, intense discussion centers on the appropriateness of BMI as a phenotypic marker of adiposity across populations differing in race and ethnicity. BMI-adiposity relations appear to vary significantly across race/ethnic groups, but a collective critical analysis of these effects establishing their magnitude and underlying body shape/composition basis is lacking. Accordingly, we systematically review the magnitude of these race-ethnic differences across non-Hispanic (NH) white, NH black and Mexican American adults, their anatomic body composition basis and potential biologically linked mechanisms, using both earlier publications and new analyses from the US National Health and Nutrition Examination Survey. Our collective observations provide a new framework for critically evaluating the quantitative relations between BMI and adiposity across groups differing in race and ethnicity; reveal new insights into BMI as a measure of adiposity across the adult age-span; identify knowledge gaps that can form the basis of future research and create a quantitative foundation for developing BMI-related public health recommendations. PMID:26663309

Enhancing research capacity of African institutions through social networking.

PubMed

Jimenez-Castellanos, Ana; Ramirez-Robles, Maximo; Shousha, Amany; Bagayoko, Cheick Oumar; Perrin, Caroline; Zolfo, Maria; Cuzin, Asa; Roland, Alima; Aryeetey, Richmond; Maojo, Victor

2013-01-01

Traditionally, participation of African researchers in top Biomedical Informatics (BMI) scientific journals and conferences has been scarce. Looking beyond these numbers, an educational goal should be to improve overall research and, therefore, to increase the number of scientists/authors able to produce and publish high quality research. In such scenario, we are carrying out various efforts to expand the capacities of various institutions located at four African countries - Egypt, Ghana, Cameroon and Mali - in the framework of a European Commission-funded project, AFRICA BUILD. This project is currently carrying out activities such as e-learning, collaborative development of informatics tools, mobility of researchers, various pilot projects, and others. Our main objective is to create a self-sustained South-South network of BMI developers.

School-based BMI and body composition screening and parent notification in California: methods and messages.

PubMed

Madsen, Kristine A; Linchey, Jennifer

2012-06-01

School-based body mass index (BMI) or body composition screening is increasing, but little is known about the process of parent notification. Since 2001, California has required annual screening of body composition via the FITNESSGRAM, with optional notification. This study sought to identify the prevalence of parental notification when screening is required but notification is optional, and the methods and messages used. Researchers conducted phone interviews with 851 school districts (89%) in California and reviewed notification materials from 54 districts. As of 2008, 53% of California districts notified parents of screening results. Many districts (24%) did not know the reason for their notification policy. Most districts notified parents via a letter mailed home (70%) or sent home with the child (18%). Whereas 79% of sample letters provided students' BMI, only 12% provided an explanation of BMI, and only half provided tips on what parents should do if concerned about their child's results. In California, where body composition screening is required but parent notification is not, approximately half of school districts elect to notify parents of results, most commonly via letter. Most letters do not explain BMI or percent body fat scores, nor do they suggest what parents should do for a child identified as at-risk. Further research to identify interpretable and actionable notification messages for parents will be critical if school-based BMI and body composition screening and notification is to reduce childhood obesity. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

Is BMI a valid measure of obesity in postmenopausal women?

PubMed

Banack, Hailey R; Wactawski-Wende, Jean; Hovey, Kathleen M; Stokes, Andrew

2018-03-01

Body mass index (BMI) is a widely used indicator of obesity status in clinical settings and population health research. However, there are concerns about the validity of BMI as a measure of obesity in postmenopausal women. Unlike BMI, which is an indirect measure of obesity and does not distinguish lean from fat mass, dual-energy x-ray absorptiometry (DXA) provides a direct measure of body fat and is considered a gold standard of adiposity measurement. The goal of this study is to examine the validity of using BMI to identify obesity in postmenopausal women relative to total body fat percent measured by DXA scan. Data from 1,329 postmenopausal women participating in the Buffalo OsteoPerio Study were used in this analysis. At baseline, women ranged in age from 53 to 85 years. Obesity was defined as BMI ≥ 30 kg/m and body fat percent (BF%) greater than 35%, 38%, or 40%. We calculated sensitivity, specificity, positive predictive value, and negative predictive value to evaluate the validity of BMI-defined obesity relative BF%. We further explored the validity of BMI relative to BF% using graphical tools, such as scatterplots and receiver-operating characteristic curves. Youden's J index was used to determine the empirical optimal BMI cut-point for each level of BF% defined obesity. The sensitivity of BMI-defined obesity was 32.4% for 35% body fat, 44.6% for 38% body fat, and 55.2% for 40% body fat. Corresponding specificity values were 99.3%, 97.1%, and 94.6%, respectively. The empirical optimal BMI cut-point to define obesity is 24.9 kg/m for 35% BF, 26.49 kg/m for 38% BF, and 27.05 kg/m for 40% BF according to the Youden's index. Results demonstrate that a BMI cut-point of 30 kg/m does not appear to be an appropriate indicator of true obesity status in postmenopausal women. Empirical estimates of the validity of BMI from this study may be used by other investigators to account for BMI-related misclassification in older women.

Cognitive biases to healthy and unhealthy food words predict change in BMI.

PubMed

Calitri, Raff; Pothos, Emmanuel M; Tapper, Katy; Brunstrom, Jeffrey M; Rogers, Peter J

2010-12-01

The current study explored the predictive value of cognitive biases to food cues (assessed by emotional Stroop and dot probe tasks) on weight change over a 1-year period. This was a longitudinal study with undergraduate students (N = 102) living in shared student accommodation. After controlling for the effects of variables associated with weight (e.g., physical activity, stress, restrained eating, external eating, and emotional eating), no effects of cognitive bias were found with the dot probe. However, for the emotional Stroop, cognitive bias to unhealthy foods predicted an increase in BMI whereas cognitive bias to healthy foods was associated with a decrease in BMI. Results parallel findings in substance abuse research; cognitive biases appear to predict behavior change. Accordingly, future research should consider strategies for attentional retraining, encouraging individuals to reorient attention away from unhealthy eating cues.

Young Adult and Usual Adult Body Mass Index and Multiple Myeloma Risk: A Pooled Analysis in the International Multiple Myeloma Consortium (IMMC).

PubMed

Birmann, Brenda M; Andreotti, Gabriella; De Roos, Anneclaire J; Camp, Nicola J; Chiu, Brian C H; Spinelli, John J; Becker, Nikolaus; Benhaim-Luzon, Véronique; Bhatti, Parveen; Boffetta, Paolo; Brennan, Paul; Brown, Elizabeth E; Cocco, Pierluigi; Costas, Laura; Cozen, Wendy; de Sanjosé, Silvia; Foretová, Lenka; Giles, Graham G; Maynadié, Marc; Moysich, Kirsten; Nieters, Alexandra; Staines, Anthony; Tricot, Guido; Weisenburger, Dennis; Zhang, Yawei; Baris, Dalsu; Purdue, Mark P

2017-06-01

Background: Multiple myeloma risk increases with higher adult body mass index (BMI). Emerging evidence also supports an association of young adult BMI with multiple myeloma. We undertook a pooled analysis of eight case-control studies to further evaluate anthropometric multiple myeloma risk factors, including young adult BMI. Methods: We conducted multivariable logistic regression analysis of usual adult anthropometric measures of 2,318 multiple myeloma cases and 9,609 controls, and of young adult BMI (age 25 or 30 years) for 1,164 cases and 3,629 controls. Results: In the pooled sample, multiple myeloma risk was positively associated with usual adult BMI; risk increased 9% per 5-kg/m 2 increase in BMI [OR, 1.09; 95% confidence interval (CI), 1.04-1.14; P = 0.007]. We observed significant heterogeneity by study design ( P = 0.04), noting the BMI-multiple myeloma association only for population-based studies ( P trend = 0.0003). Young adult BMI was also positively associated with multiple myeloma (per 5-kg/m 2 ; OR, 1.2; 95% CI, 1.1-1.3; P = 0.0002). Furthermore, we observed strong evidence of interaction between younger and usual adult BMI ( P interaction <0.0001); we noted statistically significant associations with multiple myeloma for persons overweight (25-<30 kg/m 2 ) or obese (30+ kg/m 2 ) in both younger and usual adulthood (vs. individuals consistently <25 kg/m 2 ), but not for those overweight or obese at only one time period. Conclusions: BMI-associated increases in multiple myeloma risk were highest for individuals who were overweight or obese throughout adulthood. Impact: These findings provide the strongest evidence to date that earlier and later adult BMI may increase multiple myeloma risk and suggest that healthy BMI maintenance throughout life may confer an added benefit of multiple myeloma prevention. Cancer Epidemiol Biomarkers Prev; 26(6); 876-85. ©2017 AACR . ©2017 American Association for Cancer Research.

Comparison of World Health Organization and Asia-Pacific body mass index classifications in COPD patients.

PubMed

Lim, Jeong Uk; Lee, Jae Ha; Kim, Ju Sang; Hwang, Yong Il; Kim, Tae-Hyung; Lim, Seong Yong; Yoo, Kwang Ha; Jung, Ki-Suck; Kim, Young Kyoon; Rhee, Chin Kook

2017-01-01

A low body mass index (BMI) is associated with increased mortality and low health-related quality of life in patients with COPD. The Asia-Pacific classification of BMI has a lower cutoff for overweight and obese categories compared to the World Health Organization (WHO) classification. The present study assessed patients with COPD among different BMI categories according to two BMI classification systems: WHO and Asia-Pacific. Patients with COPD aged 40 years or older from the Korean COPD Subtype Study cohort were selected for evaluation. We enrolled 1,462 patients. Medical history including age, sex, St George's Respiratory Questionnaire (SGRQ-C), the modified Medical Research Council (mMRC) dyspnea scale, and post-bronchodilator forced expiratory volume in 1 second (FEV 1 ) were evaluated. Patients were categorized into different BMI groups according to the two BMI classification systems. FEV 1 and the diffusing capacity of the lung for carbon monoxide (DLCO) percentage revealed an inverse "U"-shaped pattern as the BMI groups changed from underweight to obese when WHO cutoffs were applied. When Asia-Pacific cutoffs were applied, FEV 1 and DLCO (%) exhibited a linearly ascending relationship as the BMI increased, and the percentage of patients in the overweight and obese groups linearly decreased with increasing severity of the Global Initiative for Chronic Obstructive Lung Disease criteria. From the underweight to the overweight groups, SGRQ-C and mMRC had a decreasing relationship in both the WHO and Asia-Pacific classifications. The prevalence of comorbidities in the different BMI groups showed similar trends in both BMI classifications systems. The present study demonstrated that patients with COPD who have a high BMI have better pulmonary function and health-related quality of life and reduced dyspnea symptoms. Furthermore, the Asia-Pacific BMI classification more appropriately reflects the correlation of obesity and disease manifestation in Asian COPD patients than the WHO classification.

Relationship between Soft Drink Consumption and Obesity in 9-11 Years Old Children in a Multi-National Study.

PubMed

Katzmarzyk, Peter T; Broyles, Stephanie T; Champagne, Catherine M; Chaput, Jean-Philippe; Fogelholm, Mikael; Hu, Gang; Kuriyan, Rebecca; Kurpad, Anura; Lambert, Estelle V; Maia, Jose; Matsudo, Victor; Olds, Timothy; Onywera, Vincent; Sarmiento, Olga L; Standage, Martyn; Tremblay, Mark S; Tudor-Locke, Catrine; Zhao, Pei

2016-11-30

The purpose of this study was to determine the association between regular (sugar containing) and diet (artificially sweetened) soft drink consumption and obesity in children from 12 countries ranging in levels of economic and human development. The sample included 6162 children aged 9-11 years. Information on soft drink consumption was obtained using a food frequency questionnaire. Percentage body fat (%BF) was estimated by bio-electrical impedance analysis, body mass index (BMI) z -scores were computed using World Health Organization reference data, and obesity was defined as a BMI > +2 standard deviations (SD). Multi-level models were used to investigate trends in BMI z -scores, %BF and obesity across categories of soft drink consumption. Age, sex, study site, parental education and physical activity were included as covariates. There was a significant linear trend in BMI z -scores across categories of consumption of regular soft drinks in boys ( p = 0.049), but not in girls; there were no significant trends in %BF or obesity observed in either boys or girls. There was no significant linear trend across categories of diet soft drink consumption in boys, but there was a graded, positive association in girls for BMI z -score ( p = 0.0002) and %BF ( p = 0.0001). Further research is required to explore these associations using longitudinal research designs.

Relationship between Soft Drink Consumption and Obesity in 9–11 Years Old Children in a Multi-National Study

PubMed Central

Katzmarzyk, Peter T.; Broyles, Stephanie T.; Champagne, Catherine M.; Chaput, Jean-Philippe; Fogelholm, Mikael; Hu, Gang; Kuriyan, Rebecca; Kurpad, Anura; Lambert, Estelle V.; Maia, Jose; Matsudo, Victor; Olds, Timothy; Onywera, Vincent; Sarmiento, Olga L.; Standage, Martyn; Tremblay, Mark S.; Tudor-Locke, Catrine; Zhao, Pei

2016-01-01

The purpose of this study was to determine the association between regular (sugar containing) and diet (artificially sweetened) soft drink consumption and obesity in children from 12 countries ranging in levels of economic and human development. The sample included 6162 children aged 9–11 years. Information on soft drink consumption was obtained using a food frequency questionnaire. Percentage body fat (%BF) was estimated by bio-electrical impedance analysis, body mass index (BMI) z-scores were computed using World Health Organization reference data, and obesity was defined as a BMI > +2 standard deviations (SD). Multi-level models were used to investigate trends in BMI z-scores, %BF and obesity across categories of soft drink consumption. Age, sex, study site, parental education and physical activity were included as covariates. There was a significant linear trend in BMI z-scores across categories of consumption of regular soft drinks in boys (p = 0.049), but not in girls; there were no significant trends in %BF or obesity observed in either boys or girls. There was no significant linear trend across categories of diet soft drink consumption in boys, but there was a graded, positive association in girls for BMI z-score (p = 0.0002) and %BF (p = 0.0001). Further research is required to explore these associations using longitudinal research designs. PMID:27916866

Relations of mood with body mass index changes in severely obese women enrolled in a supported physical activity treatment.

PubMed

Annesi, James J

2008-01-01

It has been suggested that physical activity may affect weight reduction outcomes through associated improvements in mood. Relations of physical activity, mood, and weight change are not well understood in persons classified as severely obese (BMI > or = 40 kg/m(2)), however. This research tested these relationships in women with severe obesity. 57 women with a mean BMI of 43.8 kg/m(2) were enrolled in a cognitive-behavioral exercise support treatment with group-based nutrition information. Measurement of depression, tension, overall mood, and BMI was taken at baseline and month 6, and exercise session attendance was recorded. The treatment was associated with significant improvements in depression, tension and total mood disturbance scores as well as in BMI over 6 months. Changes in mood scores that were more positive were correlated with a greater reduction in BMI. Mean attendance in the prescribed 3 session/week exercise regimen was 46.0%, and attendance was significantly correlated with changes in tension and total mood disturbance scores, and approached significance with changes in depression scores. Findings suggested significant relations of mood and weight change as well as of physical activity and mood in severely obese women associated with a treatment of moderate physical activity. With extensions of this research, weight loss theory and treatment may benefit. Copyright 2008 S. Karger AG, Basel.

Asthma, Smoking and BMI in Adults with Intellectual Disabilities: A Community-Based Survey

ERIC Educational Resources Information Center

Gale, L.; Naqvi, H.; Russ, L.

2009-01-01

Background: Recent research evidence from the general population has shown that tobacco smoking and raised body mass index (BMI) are associated with worse asthma outcomes. There are indications that asthma morbidity and mortality may be higher among people with intellectual disabilities (ID) than the general population, but the reason for this is…

Nonlinear association of BMI with all-cause and cardiovascular mortality in type 2 diabetes mellitus: a systematic review and meta-analysis of 414,587 participants in prospective studies.

PubMed

Zaccardi, Francesco; Dhalwani, Nafeesa N; Papamargaritis, Dimitris; Webb, David R; Murphy, Gavin J; Davies, Melanie J; Khunti, Kamlesh

2017-02-01

The relationship between BMI and mortality has been extensively investigated in the general population; however, it is less clear in people with type 2 diabetes. We aimed to assess the association of BMI with all-cause and cardiovascular mortality in individuals with type 2 diabetes mellitus. We searched electronic databases up to 1 March 2016 for prospective studies reporting associations for three or more BMI groups with all-cause and cardiovascular mortality in individuals with type 2 diabetes mellitus. Study-specific associations between BMI and the most-adjusted RR were estimated using restricted cubic splines and a generalised least squares method before pooling study estimates with a multivariate random-effects meta-analysis. We included 21 studies including 24 cohorts, 414,587 participants, 61,889 all-cause and 4470 cardiovascular incident deaths; follow-up ranged from 2.7 to 15.9 years. There was a strong nonlinear relationship between BMI and all-cause mortality in both men and women, with the lowest estimated risk from 31-35 kg/m 2 and 28-31 kg/m 2 (p value for nonlinearity <0.001) respectively. The risk of mortality at higher BMI values increased significantly only in women, whilst lower values were associated with higher mortality in both sexes. Limited data for cardiovascular mortality were available, with a possible inverse linear association with BMI (higher risk for BMI <27 kg/m 2 ). In type 2 diabetes, BMI is nonlinearly associated with all-cause mortality with lowest risk in the overweight group in both men and women. Further research is needed to clarify the relationship with cardiovascular mortality and assess causality and sex differences.

Association between body mass index and mortality in patients with glioblastoma mutliforme.

PubMed

Jones, Lee W; Ali-Osman, Francis; Lipp, Eric; Marcello, Jennifer E; McCarthy, Bridget; McCoy, Lucie; Rice, Terri; Wrensch, Margaret; Il'yasova, Dora

2010-12-01

To examine the association between obesity and survival in patients with glioblastoma mutliforme (GBM) METHODS: Using a prospective design, 1,259 patients with previously untreated GBM were recruited between 1991 and 2008. Height and weight were self-reported or abstracted from medical records at study entry and used to calculate body mass index (BMI) [weight (kg)/[height (m)](2). Cox proportional models were used to estimate the risk of death associated with BMI as a continuous variable or categorized using established criteria (normal weight, 18.5-24.9 kg/m(2); overweight, 25.0-29.9 kg/m(2); obese, ≥ 30.0 kg/m(2)). Median follow-up was 40 months, and 1,069 (85%) deaths were observed during this period. For all patients, minimal adjusted analyses indicated no significant association between BMI treated as a continuous variable and survival. Compared with patients with a BMI 18.5-24.9 kg/m(2), the minimally adjusted HR for overall survival was 1.08 (95% CI, 0.94-1.24) for a BMI 25-29.9 kg/m(2) and 1.08 (95% CI, 0.91-28) for a BMI ≥ 30.0 kg/m(2). After additional adjustment for adjuvant therapy, the HR for those with a BMI of 25.0-29.9 kg/m(2) was 1.14 (95% CI, 0.99-1.32) and 1.09 (95% CI, 0.91-1.30) for those with a BMI ≥ 30.0 kg/m(2). No significant interactions were revealed for BMI and any demographic variables. BMI was not associated with survival in newly diagnosed and previously untreated patients with GBM. Further research investigating the prognostic significance of alternative, quantitative measures of body habitus, and functional performance are required.

Parental body mass index is associated with adolescent overweight and obesity in Mashhad, Iran.

PubMed

Shafaghi, Khosro; Shariff, Zalilah Mohd; Taib, Mohd Nasir Mohd; Rahman, Hejar Abdul; Mobarhan, Majid Ghayour; Jabbari, Hadi

2014-01-01

This cross-sectional study was carried out to determine the prevalence of overweight and obesity among secondary school children aged 12 to 14 years in the city of Mashhad, Iran and its association with parental body mass index. A total of 1189 secondary school children (579 males and 610 females) aged 12- 14 years old were selected through a stratified multistage random sampling. All adolescents were measured for weight and height. Household socio-demographic information and parental weight and height were self-reported by parents. Adolescents were classified as overweight or obese based on BMI-for age Z-score. Multivariable logistic Regression (MLR) determined the relationship between parental BMI and adolescent overweight and obesity. The overall prevalence of overweight and obesity among secondary school children in Mashhad was 17.2% and 11.9%, respectively. A higher proportion of male (30.7%) than female (27.4%) children were overweight or obese. BMI of the children was significantly related to parental BMI (p<0.001), gender (p= 0.02), birth order (p<0.01), parents' education level (p<0.001), father's employment status (p<0.001), and family income (p<0.001). MLR showed that the father's BMI was significantly associated with male BMI (OR: 2.02) and female BMI (OR: 1.59), whereas the mother's BMI was significantly associated with female BMI only (OR: 0.514). The high prevalence of overweight/obesity among the research population compared with previous studies in Iran could be related to the changing lifestyle of the population. The strong relationship with parental BMI was probably related to a combination of genetic and lifestyle factors. Strategies to address childhood obesity should consider the interaction of these factors.

Food Reinforcement and Parental Obesity Predict Future Weight Gain in Non-Obese Adolescents

PubMed Central

Epstein, Leonard H.; Yokum, Sonja; Feda, Denise M.; Stice, Eric

2014-01-01

Background Food reinforcement, the extent to which people are willing to work to earn a preferred snack food, and parental obesity are risk factors for weight gain, but there is no research comparing the predictive effects of these factors for adolescent weight gain. Methods 130 non-obese adolescents (M age = 15.2 ± 1.0; M BMI = 20.7 ± 2.0; M zBMI = 0.16 ± 0.64) at differential risk for weight gain based on parental obesity completed baseline food and money reinforcement tasks, and provided zBMI data over 2-yr follow-up. Results The number of obese (BMI ≥ 30) parents (p = 0.007) and high food reinforcement (p = 0.046) were both significant independent predictors of greater zBMI increases, controlling for age, sex, parent education and minority status. Having no obese parents or being low or average in food reinforcement was associated with reductions in zBMI, but those high in food reinforcement showed larger zBMI increases (0.102) than having one obese parent (0.025) but less than having two obese parents (0.177). Discussion Food reinforcement and parental obesity independently predict future weight gain among adolescents. It might be fruitful for obesity prevention programs to target both high risk groups. PMID:25045864

RatCar system for estimating locomotion states using neural signals with parameter monitoring: Vehicle-formed brain-machine interfaces for rat.

PubMed

Fukayama, Osamu; Taniguchi, Noriyuki; Suzuki, Takafumi; Mabuchi, Kunihiko

2008-01-01

An online brain-machine interface (BMI) in the form of a small vehicle, the 'RatCar,' has been developed. A rat had neural electrodes implanted in its primary motor cortex and basal ganglia regions to continuously record neural signals. Then, a linear state space model represents a correlation between the recorded neural signals and locomotion states (i.e., moving velocity and azimuthal variances) of the rat. The model parameters were set so as to minimize estimation errors, and the locomotion states were estimated from neural firing rates using a Kalman filter algorithm. The results showed a small oscillation to achieve smooth control of the vehicle in spite of fluctuating firing rates with noises applied to the model. Major variation of the model variables converged in a first 30 seconds of the experiments and lasted for the entire one hour session.

Toughening and healing of continuous fibre reinforced composites with bis-maleimide based pre-pregs

NASA Astrophysics Data System (ADS)

Kostopoulos, V.; Kotrotsos, A.; Tsantzalis, S.; Tsokanas, P.; Christopoulos, A. C.; Loutas, T.

2016-08-01

Unidirectional (UD) pre-pregs containing self-healing materials based on Diels-Alder reaction bis-maleimide (BMI) polymers were successfully incorporated on the mid-plane of UD carbon fibre reinforced polymers. The fracture toughness of these composites and the introduced healing capability were measured under mode I loading. The interlaminar fracture toughness was enhanced considerably, since the maximum load (P max) of the modified composite increased approximately 1.5 times and the mode I fracture energy (G IC) displayed a significant increase of almost 3.5 times when compared to the reference composites. Furthermore the modified composites displayed a healing efficiency (HE) value of about 30% for P max and 20% for G IC after the first healing, appearing to be an almost stable behaviour after the third healing cycle. The HE displayed a decrease of 20% and 15% for P max and G IC values, respectively, after the fifth healing cycle. During the tests, the monitored acoustic emission (AE) activity of the samples showed that there is no significant difference due to the presence of BMI polymer in terms of AE hits. Moreover, optical microscopy not only showed that the epoxy matrix at the interface is partly infiltrated by the BMI polymer, but it also revealed the presence of pulled out fibres at the fractured surface, indicating ductile behaviour.

Detecting the Intention to Move Upper Limbs from Electroencephalographic Brain Signals.

PubMed

Gudiño-Mendoza, Berenice; Sanchez-Ante, Gildardo; Antelis, Javier M

2016-01-01

Early decoding of motor states directly from the brain activity is essential to develop brain-machine interfaces (BMI) for natural motor control of neuroprosthetic devices. Hence, this study aimed to investigate the detection of movement information before the actual movement occurs. This information piece could be useful to provide early control signals to drive BMI-based rehabilitation and motor assisted devices, thus providing a natural and active rehabilitation therapy. In this work, electroencephalographic (EEG) brain signals from six healthy right-handed participants were recorded during self-initiated reaching movements of the upper limbs. The analysis of these EEG traces showed that significant event-related desynchronization is present before and during the execution of the movements, predominantly in the motor-related α and β frequency bands and in electrodes placed above the motor cortex. This oscillatory brain activity was used to continuously detect the intention to move the limbs, that is, to identify the motor phase prior to the actual execution of the reaching movement. The results showed, first, significant classification between relax and movement intention and, second, significant detection of movement intention prior to the onset of the executed movement. On the basis of these results, detection of movement intention could be used in BMI settings to reduce the gap between mental motor processes and the actual movement performed by an assisted or rehabilitation robotic device.

Metabolic mediators of the effects of body-mass index, overweight, and obesity on coronary heart disease and stroke: a pooled analysis of 97 prospective cohorts with 1·8 million participants

PubMed Central

2014-01-01

Summary Background Body-mass index (BMI) and diabetes have increased worldwide, whereas global average blood pressure and cholesterol have decreased or remained unchanged in the past three decades. We quantified how much of the effects of BMI on coronary heart disease and stroke are mediated through blood pressure, cholesterol, and glucose, and how much is independent of these factors. Methods We pooled data from 97 prospective cohort studies that collectively enrolled 1·8 million participants between 1948 and 2005, and that included 57 161 coronary heart disease and 31 093 stroke events. For each cohort we excluded participants who were younger than 18 years, had a BMI of lower than 20 kg/m2, or who had a history of coronary heart disease or stroke. We estimated the hazard ratio (HR) of BMI on coronary heart disease and stroke with and without adjustment for all possible combinations of blood pressure, cholesterol, and glucose. We pooled HRs with a random-effects model and calculated the attenuation of excess risk after adjustment for mediators. Findings The HR for each 5 kg/m2 higher BMI was 1·27 (95% CI 1·23–1·31) for coronary heart disease and 1·18 (1·14–1·22) for stroke after adjustment for confounders. Additional adjustment for the three metabolic risk factors reduced the HRs to 1·15 (1·12–1·18) for coronary heart disease and 1·04 (1·01–1·08) for stroke, suggesting that 46% (95% CI 42–50) of the excess risk of BMI for coronary heart disease and 76% (65–91) for stroke is mediated by these factors. Blood pressure was the most important mediator, accounting for 31% (28–35) of the excess risk for coronary heart disease and 65% (56–75) for stroke. The percentage excess risks mediated by these three mediators did not differ significantly between Asian and western cohorts (North America, western Europe, Australia, and New Zealand). Both overweight (BMI ≥25 to <30 kg/m2) and obesity (BMI ≥30 kg/m2) were associated with a significantly increased risk of coronary heart disease and stroke, compared with normal weight (BMI ≥20 to <25 kg/m2), with 50% (44–58) of the excess risk of overweight and 44% (41–48) of the excess risk of obesity for coronary heart disease mediated by the selected three mediators. The percentages for stroke were 98% (69–155) for overweight and 69% (64–77) for obesity. Interpretation Interventions that reduce high blood pressure, cholesterol, and glucose might address about half of excess risk of coronary heart disease and three-quarters of excess risk of stroke associated with high BMI. Maintenance of optimum bodyweight is needed for the full benefits. Funding US National Institute of Health, UK Medical Research Council, National Institute for Health Research Comprehensive Biomedical Research Centre at Imperial College Healthcare NHS Trust, Lown Scholars in Residence Program on cardiovascular disease prevention, and Harvard Global Health Institute Doctoral Research Grant. PMID:24269108

Metabolic mediators of the effects of body-mass index, overweight, and obesity on coronary heart disease and stroke: a pooled analysis of 97 prospective cohorts with 1·8 million participants.

PubMed

Lu, Yuan; Hajifathalian, Kaveh; Ezzati, Majid; Woodward, Mark; Rimm, Eric B; Danaei, Goodarz

2014-03-15

Body-mass index (BMI) and diabetes have increased worldwide, whereas global average blood pressure and cholesterol have decreased or remained unchanged in the past three decades. We quantified how much of the effects of BMI on coronary heart disease and stroke are mediated through blood pressure, cholesterol, and glucose, and how much is independent of these factors. We pooled data from 97 prospective cohort studies that collectively enrolled 1·8 million participants between 1948 and 2005, and that included 57,161 coronary heart disease and 31,093 stroke events. For each cohort we excluded participants who were younger than 18 years, had a BMI of lower than 20 kg/m(2), or who had a history of coronary heart disease or stroke. We estimated the hazard ratio (HR) of BMI on coronary heart disease and stroke with and without adjustment for all possible combinations of blood pressure, cholesterol, and glucose. We pooled HRs with a random-effects model and calculated the attenuation of excess risk after adjustment for mediators. The HR for each 5 kg/m(2) higher BMI was 1·27 (95% CI 1·23-1·31) for coronary heart disease and 1·18 (1·14-1·22) for stroke after adjustment for confounders. Additional adjustment for the three metabolic risk factors reduced the HRs to 1·15 (1·12-1·18) for coronary heart disease and 1·04 (1·01-1·08) for stroke, suggesting that 46% (95% CI 42-50) of the excess risk of BMI for coronary heart disease and 76% (65-91) for stroke is mediated by these factors. Blood pressure was the most important mediator, accounting for 31% (28-35) of the excess risk for coronary heart disease and 65% (56-75) for stroke. The percentage excess risks mediated by these three mediators did not differ significantly between Asian and western cohorts (North America, western Europe, Australia, and New Zealand). Both overweight (BMI ≥25 to <30 kg/m(2)) and obesity (BMI ≥30 kg/m(2)) were associated with a significantly increased risk of coronary heart disease and stroke, compared with normal weight (BMI ≥20 to <25 kg/m(2)), with 50% (44-58) of the excess risk of overweight and 44% (41-48) of the excess risk of obesity for coronary heart disease mediated by the selected three mediators. The percentages for stroke were 98% (69-155) for overweight and 69% (64-77) for obesity. Interventions that reduce high blood pressure, cholesterol, and glucose might address about half of excess risk of coronary heart disease and three-quarters of excess risk of stroke associated with high BMI. Maintenance of optimum bodyweight is needed for the full benefits. US National Institute of Health, UK Medical Research Council, National Institute for Health Research Comprehensive Biomedical Research Centre at Imperial College Healthcare NHS Trust, Lown Scholars in Residence Program on cardiovascular disease prevention, and Harvard Global Health Institute Doctoral Research Grant. Copyright © 2014 Elsevier Ltd. All rights reserved.

Eating behavior, weight problems and eating disorders in 101 long-term survivors of childhood-onset craniopharyngioma.

PubMed

Hoffmann, Anika; Postma, Frank P; Sterkenburg, Anthe S; Gebhardt, Ursel; Müller, Hermann L

2015-01-01

As a result of hypothalamic involvement and/or treatment-related hypothalamic damage, up to 75% of childhood craniopharyngioma patients develop hypothalamic obesity. Eating behavior was analyzed in 101 survivors of childhood craniopharyngioma, recruited from 1980 to 2001 in the HIT-Endo multicenter study, and in 85 body mass index (BMI)-matched healthy controls using the Inventory for Eating Behavior and Weight Problems (IEG) and the Inventory for Eating Disorders (ESI). Severely obese patients (BMI>8 SD; n=9) presented with pathological eating behavior, more weight problems, and eating disorders, as compared to obese (BMI 3-8 SD; n=44) and normal or overweight patients (BMI<3 SD; n=48). Craniopharyngioma patients with different degrees of obesity showed similar or even less pathological findings as compared to BMI-matched normal controls. Severe obesity is associated with pathological eating behavior/disorders in craniopharyngioma patients. As these disorders are not disease-specific, risk factors for hypothalamic obesity should be the focus of further craniopharyngioma research.

From the BMI paradox to the obesity paradox: the obesity-mortality association in coronary heart disease.

PubMed

Antonopoulos, A S; Oikonomou, E K; Antoniades, C; Tousoulis, D

2016-10-01

Despite a strong association between body weight and mortality in the general population, clinical evidence suggests better clinical outcome of overweight or obese individuals with established coronary heart disease. This finding has been termed the 'obesity paradox', but its existence remains a point of debate, because it is mostly observed when body mass index (BMI) is used to define obesity. Inherent limitations of BMI as an index of adiposity, as well as methodological biases and the presence of confounding factors, may account for the observed findings of clinical studies. In this review, our aim is to present the data that support the presence of a BMI paradox in coronary heart disease and then explore whether next to a BMI paradox a true obesity paradox exists as well. We conclude by attempting to link the obesity paradox notion to available translational research data supporting a 'healthy', protective adipose tissue phenotype. © 2016 World Obesity. © 2016 World Obesity.

Infant BMI peak as a predictor of overweight and obesity at age 2 years in a Chinese community-based cohort

PubMed Central

Sun, Jie; Nwaru, Bright I; Hua, Jing; Li, Xiaohong; Wu, Zhuochun

2017-01-01

Objectives Infant body mass index (BMI) peak has proven to be a useful indicator for predicting childhood obesity risk in American and European populations. However, it has not been assessed in China. We characterised infant BMI trajectories in a Chinese longitudinal cohort and evaluated whether BMI peak can predict overweight and obesity at age 2 years. Methods Serial measurements (n=6–12) of weight and length were taken from healthy term infants (n=2073) in a birth cohort established in urban Shanghai. Measurements were used to estimate BMI growth curves from birth to 13.5 months using a polynomial regression model. BMI peak characteristics, including age (in months) and magnitude (BMI, in kg/m2) at peak and prepeak velocities (in kg/m2/month), were estimated. The relationship between infant BMI peak and childhood BMI at age 2 years was examined using binary logistic analysis. Results Mean age at peak BMI was 7.61 months, with a magnitude of 18.33 kg/m2. Boys (n=1022) had a higher average peak BMI (18.60 vs 18.07 kg/m2, p<0.001) and earlier average achievement of peak value (7.54 vs 7.67 months, p<0.05) than girls (n=1051). With 1 kg/m2 increase in peak BMI and 1 month increase in peak time, the risk of overweight at age 2 years increased by 2.11 times (OR 3.11; 95% CI 2.64 to 3.66) and 35% (OR 1.35; 95% CI 1.21 to 1.50), respectively. Similarly, higher BMI magnitude (OR 2.69; 95% CI 2.00 to 3.61) and later timing of infant BMI peak (OR 1.35; 95% CI 1.08 to 1.68) were associated with an increased risk of childhood obesity at age 2 years. Conclusions We have shown that infant BMI peak is valuable for predicting early childhood overweight and obesity in urban Shanghai. Because this is the first Chinese community-based cohort study of this nature, future research is required to examine infant populations in other areas of China. PMID:28988164

Pharmacokinetics of levonorgestrel and ulipristal acetate emergency contraception in women with normal and obese body mass index.

PubMed

Praditpan, Piyapa; Hamouie, Angie; Basaraba, Cale N; Nandakumar, Renu; Cremers, Serge; Davis, Anne R; Westhoff, Carolyn L

2017-05-01

This study compares the pharmacokinetics (PK) of levonorgestrel (LNG) emergency contraceptive (EC) and ulipristal acetate (UPA)-EC between normal-body mass index (BMI) and obese-BMI women. This prospective, randomized crossover study evaluates the PK of women after single doses of LNG-EC (1.5mg) and UPA-EC (30mg). Study procedures took place during clinical research unit admissions, where participants received a standardized meal and each study drug, in random order, during two separate 24-h admissions. Study staff collected 14 blood specimens (0, 0.5, 1.0, 1.5, 2, 3, 4, 6, 8, 10, 12, 16, 24 and 48h). We evaluated serum concentrations of LNG and UPA using liquid chromatography-tandem mass spectroscopy and estimated the PK parameters of both drugs using noncompartmental analysis. The main outcome of this study was a comparison of between-group differences in AUC 0-24 . Thirty-two women completed the study (16 in each group). Among normal-BMI and obese-BMI participants, the mean BMIs were 22.0 (range 18.8-24.6) and 34.3 (range 30.6-39.9), respectively. After LNG-EC, mean AUC 0-24 and maximum concentration (C max ) were 50% lower among obese-BMI women than among normal-BMI women (AUC 0-24 100.8 vs. 208.5ng*h/mL, IQR obese-BMI 35.8, IQR normal-BMI 74.2, p≤.01; C max 10.8 vs. 18.2ng/mL, p=.01). After UPA-EC, AUC 0-24 and C max were similar between obese-BMI and normal-BMI women (AUC 0-24 362.5 vs. 293.5ng*h/mL, IQR obese-BMI 263.2, IQR normal-BMI 112.5, p=.15; C max 95.6 vs. 89.3ng/mL, p=.70). After a single dose of EC, obese-BMI women are exposed to lower concentrations of LNG and similar concentrations of UPA, when compared to normal-BMI women. Differences in LNG-EC PK by BMI group may underlie and account for the lower LNG-EC efficacy reported among obese-BMI women, but modest differences in UPA-EC PK by BMI group provide less support for variable efficacy. A pharmacodynamic study may be able to clarify whether these PK differences account for observed differences in LNG-EC and UPA-EC efficacy. Copyright © 2017 Elsevier Inc. All rights reserved.

Mediation and modification of genetic susceptibility to obesity by eating behaviors.

PubMed

de Lauzon-Guillain, Blandine; Clifton, Emma Ad; Day, Felix R; Clément, Karine; Brage, Soren; Forouhi, Nita G; Griffin, Simon J; Koudou, Yves Akoli; Pelloux, Véronique; Wareham, Nicholas J; Charles, Marie-Aline; Heude, Barbara; Ong, Ken K

2017-10-01

Background: Many genetic variants show highly robust associations with body mass index (BMI). However, the mechanisms through which genetic susceptibility to obesity operates are not well understood. Potentially modifiable mechanisms, including eating behaviors, are of particular interest to public health. Objective: Here we explore whether eating behaviors mediate or modify genetic susceptibility to obesity. Design: Genetic risk scores for BMI (BMI-GRSs) were calculated for 3515 and 2154 adults in the Fenland and EDEN (Etude des déterminants pré et postnatals de la santé et du développement de l'enfant) population-based cohort studies, respectively. The eating behaviors-emotional eating, uncontrolled eating, and cognitive restraint-were measured through the use of a validated questionnaire. The mediating effect of each eating behavior on the association between the BMI-GRS and measured BMI was assessed by using the Sobel test. In addition, we tested for interactions between each eating behavior and the BMI-GRS on BMI. Results: The association between the BMI-GRS and BMI was mediated by both emotional eating (EDEN: P- Sobel = 0.01; Fenland: P- Sobel = 0.02) and uncontrolled eating (EDEN: P- Sobel = 0.04; Fenland: P -Sobel = 0.0006) in both sexes combined. Cognitive restraint did not mediate this association ( P -Sobel > 0.10), except among EDEN women ( P -Sobel = 0.0009). Cognitive restraint modified the relation between the BMI-GRS and BMI among men (EDEN: P -interaction = 0.0001; Fenland: P -interaction = 0.04) and Fenland women ( P -interaction = 0.0004). By tertiles of cognitive restraint, the association between the BMI-GRS and BMI was strongest in the lowest tertile of cognitive restraint, and weakest in the highest tertile. Conclusions: Genetic susceptibility to obesity was partially mediated by the "appetitive" eating behavior traits (uncontrolled and emotional eating) and, in 3 of the 4 population groups studied, was modified by cognitive restraint. High levels of cognitive control over eating appear to attenuate the genetic susceptibility to obesity. Future research into interventions designed to support restraint may help to protect genetically susceptible individuals from weight gain. © 2017 American Society for Nutrition.

A Survey of the Job Profiles of Biomedical Informatics Graduates.

PubMed

Macedo, Alessandra A; Ruiz, Evandro E S; Baranauskas, José A

2016-10-17

In 2003, the University of São Paulo established the first Biomedical Informatics (BMI) undergraduate course in Brazil. Our mission is to provide undergraduate students with formal education on the fundamentals of BMI and its applied methods. This undergraduate course offers theoretical aspects, practical knowledge and scientifically oriented skills in the area of BMI, enab- ling students to contribute to research and methodical development in BMI. Course coordinators, professors and students frequently evaluate the BMI course and the curriculum to ensure that alumni receive quality higher education. This study investigates (i) the main job activities undertake by USP BMI graduates, (ii) subjects that are fundamental important for graduates to pursue a career in BMI, and (iii) the course quality perceived by the alumni. Use of a structured questionnaire to conduct a survey involving all the BMI graduates who received their Bachelor degree before July, 2015 (attempted n = 205). One hundred and forty-five graduates (71 %) answered the questionnaire. Nine out of ten of our former students currently work as informaticians. Seventy-six graduates (52 %) work within the biomedical informatics field. Fifty-five graduates (38 %) work outside the biomedical informatics field, but they work in other IT areas. Ten graduates (7 %) do not work with BMI or any other informatics activities, and four (3 %) are presently unemployed. Among the 145 surveyed BMI graduates, 46 (32 %) and seven (5 %) hold a Master's degree and a PhD degree, respectively. Database Systems, Software Engineering, Introduction to Computer Science, Object-Oriented Programming, and Data Structures are regarded as the most important subjects during the higher education course. The majority of the graduates (105 or 72 %) are satisfied with the BMI education and training they received during the undergraduate course. More than half of the graduates from our BMI course work in their primary education area. Besides technical adequacy, the diverse job profiles, and the high level of satisfaction of our graduates indicate the importance of undergraduate courses specialized in the BMI domain are of utmost importance.

Who Self-Weighs and What Do They Gain From It? A Retrospective Comparison Between Smart Scale Users and the General Population in England.

PubMed

Sperrin, Matthew; Rushton, Helen; Dixon, William G; Normand, Alexis; Villard, Joffrey; Chieh, Angela; Buchan, Iain

2016-01-21

Digital self-monitoring, particularly of weight, is increasingly prevalent. The associated data could be reused for clinical and research purposes. The aim was to compare participants who use connected smart scale technologies with the general population and explore how use of smart scale technology affects, or is affected by, weight change. This was a retrospective study comparing 2 databases: (1) the longitudinal height and weight measurement database of smart scale users and (2) the Health Survey for England, a cross-sectional survey of the general population in England. Baseline comparison was of body mass index (BMI) in the 2 databases via a regression model. For exploring engagement with the technology, two analyses were performed: (1) a regression model of BMI change predicted by measures of engagement and (2) a recurrent event survival analysis with instantaneous probability of a subsequent self-weighing predicted by previous BMI change. Among women, users of self-weighing technology had a mean BMI of 1.62 kg/m(2) (95% CI 1.03-2.22) lower than the general population (of the same age and height) (P<.001). Among men, users had a mean BMI of 1.26 kg/m(2) (95% CI 0.84-1.69) greater than the general population (of the same age and height) (P<.001). Reduction in BMI was independently associated with greater engagement with self-weighing. Self-weighing events were more likely when users had recently reduced their BMI. Users of self-weighing technology are a selected sample of the general population and this must be accounted for in studies that employ these data. Engagement with self-weighing is associated with recent weight change; more research is needed to understand the extent to which weight change encourages closer monitoring versus closer monitoring driving the weight change. The concept of isolated measures needs to give way to one of connected health metrics.

The mediating role of dichotomous thinking and emotional eating in the relationship between depression and BMI.

PubMed

Antoniou, Evangelia E; Bongers, Peggy; Jansen, Anita

2017-08-01

Obesity and depression have important health implications. Although there is knowledge about the moderators of the depression-obesity association, our understanding of the potential behavioral and cognitive mediators that may explain the relationship between depression and obesity, is scarcely researched. The aim of this study is to investigate the mediating role of emotional eating and dichotomous thinking in the depression-obesity relationship. Data on 205 individuals from a community-based study conducted at Maastricht University, Netherlands were used. Self-reported data on depression, emotional eating and dichotomous thinking were collected and BMI scores were calculated in a cross-sectional research design. Correlations between variables were calculated. The primary analysis tested the hypothesis that depression has an effect on BMI through dichotomous thinking and emotional eating. A two-mediator model was used to predict the direct and indirect effects of emotional eating and dichotomous thinking on the depression-BMI relationship. Depression was positively correlated with BMI (r=0.21, p=0.005), emotional eating (r=0.38, p<0.001) and dichotomous thinking (r=0.49, p<0.001). Dichotomous thinking and emotional eating were positively correlated with BMI (r=0.35, p<0.001; and r=0.45, p<0.001 respectively). Both dichotomous thinking (Z=2.54, p=0.01, 95% confidence intervals=0.01-0.17) and emotional eating (Z=3.92 p<0.001, 95% confidence intervals=0.06-0.19) could explain the depression-BMI relationship. The assessment of emotional eating and dichotomous thinking might be useful in guiding assessment and treatment protocols for weight management. The present study adds to the existing literature on the role of dysfunctional cognitions and emotions on eating behavior, and particularly to the factors that may impede people's ability to control their eating. Copyright © 2017 Elsevier Ltd. All rights reserved.

Association Between Weekend Catch-up Sleep and Lower Body Mass: Population-Based Study.

PubMed

Im, Hee-Jin; Baek, Shin-Hye; Chu, Min Kyung; Yang, Kwang Ik; Kim, Won-Joo; Park, Seong-Ho; Thomas, Robert J; Yun, Chang-Ho

2017-07-01

To determine if weekend catch-up sleep (CUS) impacts body mass index (BMI) in the general population. A stratified random sample (2156 subjects; age 19-82 years old, 43.0 ± 14.5; 1183 male) from the general population was evaluated, in 2010, using face-to-face interviews about sociodemographic characteristics, height, weight, habitual sleep duration, and time-in-bed at night on weekdays and weekend, sleep-related profiles, mood and anxiety scales, and comorbid-medical conditions. Weekend CUS was identified when nocturnal sleep extension occurred over the weekend, and this was quantified. Average sleep duration, BMI, and chronotype were determined. The association of BMI with the presence and the amount of weekend CUS was analyzed, independent of average sleep duration, chronotype, and sociodemographic factors. BMI and average sleep duration was 23.0 ± 3.0 kg/m2 and 7.3 ± 1.2 hours, respectively. The weekend CUS group consisted of 932 subjects (43.1%) who slept longer on weekend than weekdays by 1.8 ± 1.1 hours. Weekend CUS subjects had a significantly lower BMI (22.8 ± 0.19 kg/m2) than the non-CUS (23.1 ± 0.19 kg/m2) group, after adjustment for age, sex, average sleep duration, chronotype, other sociodemographic factors, and anxiety/mood status (p = .01) The relationship between weekend CUS and BMI was dose-dependent (p = 0.02): Every additional hour of weekend CUS was associated with a decrease of 0.12 kg/m2 in BMI (95% confidence interval, -0.23 to -0.02). Weekend sleep extension may have biological protective effects in preventing sleep-restriction induced or related obesity. The results suggest a simple population-level strategy to minimize effects of sleep loss. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Reflections on biomedical informatics: from cybernetics to genomic medicine and nanomedicine.

PubMed

Maojo, Victor; Kulikowski, Casimir A

2006-01-01

Expanding on our previous analysis of Biomedical Informatics (BMI), the present perspective ranges from cybernetics to nanomedicine, based on its scientific, historical, philosophical, theoretical, experimental, and technological aspects as they affect systems developments, simulation and modelling, education, and the impact on healthcare. We then suggest that BMI is still searching for strong basic scientific principles around which it can crystallize. As -omic biological knowledge increasingly impacts the future of medicine, ubiquitous computing and informatics become even more essential, not only for the technological infrastructure, but as a part of the scientific enterprise itself. The Virtual Physiological Human and investigations into nanomedicine will surely produce yet more unpredictable opportunities, leading to significant changes in biomedical research and practice. As a discipline involved in making such advances possible, BMI is likely to need to re-define itself and extend its research horizons to meet the new challenges.

Food outlet visits, physical activity and body weight: variations by gender and race-ethnicity.

PubMed

Frank, L; Kerr, J; Saelens, B; Sallis, J; Glanz, K; Chapman, J

2009-02-01

Recent evidence documents significant associations between community design, physical activity and obesity when adjusting for demographic covariates. Yet it is well understood that energy imbalance and weight gain are also a function of dietary patterns, and perhaps the degree of access to healthy food choices. The current study builds upon the Atlanta-based SMARTRAQ study of over 10,000 respondents and reports an integrated assessment of obesity impacts of physical activity and food outlet visitation. Respondents in the SMARTRAQ survey aged 25-65 provided BMI, self-reported physical activity levels (IPAQ), demographic factors, and where they went for food over a 2 day period. The relative effect of physical activity, neighbourhood walkability, and food outlet visitation on BMI differed significantly across gender and ethnicity. BMI in females increased with fast food and decreased with grocery store visitation and physical activity, but not with walkability or walking. BMI in males was not related to where they went for food but decreased with walking and overall physical activity and with walkability. Fast food visitation was associated with increased BMI in white respondents and grocery store visitation with decreased BMI in black respondents. Meeting moderate activity guidelines was associated with lower BMI in both black and white respondents, yet walking was only significant in predicting reduced BMI in white respondents. Obesity influences of physical activity, walkability, and where people go for food differ significantly across gender and ethnicity and offer important policy implications and insights for future research.

Association of fat mass and obesity-associated and retinitis pigmentosa guanosine triphosphatase (GTPase) regulator-interacting protein-1 like polymorphisms with body mass index in Chinese women.

PubMed

Chen, Boyu; Li, Zhiqiang; Chen, Jianhua; Ji, Jue; Shen, Jingyi; Xu, Yufeng; Zhao, Yingying; Liu, Danping; Shen, Yinhuan; Zhang, Weijie; Shen, Jiawei; Wang, Yonggang; Shi, Yongyong

2018-04-14

Body mass index (BMI) is the most commonly used quantitative measure of adiposity. It is a kind of complex genetic diseases which are caused by multiple susceptibility genes. The first intron of fat mass and obesity-associated (FTO) has been widely discovered to be associated with BMI. Retinitis pigmentosa GTPase regulator-interacting protein-1 like (RPGRIP1L) is located in the upstream region of FTO and has been proved to be linked with obesity through functional tests. We carried out a genetic association analysis to figure out the role of the FTO gene and the RPGRIP1L gene in BMI. A quantitative traits study with 6,102 Chinese female samples, adjusted for age, was performed during our project. Among the twelve SNPs, rs1421085, rs1558902, rs17817449, rs8050136, rs9939609, rs7202296, rs56137030, rs9930506 and rs12149832 in the FTO gene were significantly associated with BMI after Bonferroni correction. Meanwhile, rs9934800 in the RPGRIP1L gene showed significance with BMI before Bonferroni correction, but this association was eliminated after Bonferroni correction. Our results suggested that genetic variants in the FTO gene were strongly associated with BMI in Chinese women, which may serve as targets of pharmaceutical research and development concerning BMI. Meanwhile, we didn't found the significant association between RPGRIP1L and BMI in Chinese women.

Decision-Making Does not Moderate the Association between Cannabis Use and Body Mass Index among Adolescent Cannabis Users.

PubMed

Ross, J Megan; Graziano, Paulo; Pacheco-Colón, Ileana; Coxe, Stefany; Gonzalez, Raul

2016-10-01

Results from research conducted on the association between cannabis use and body mass index (BMI) reveal mixed findings. It is possible that individual differences in decision-making (DM) abilities may influence these associations. This study analyzed how amount of cannabis use, DM performance, and the interaction of these variables influenced BMI and clinical classifications of weight among adolescents (ages 14 to 18 years; 56% male; 77% Hispanic). The sample consisted primarily of cannabis users (n=238) without a history of significant developmental disorders, birth complications, neurological conditions, or history of mood, thought, or attention deficit/hyperactivity disorder at screening. Furthermore, few participants engaged frequently in other drug use (except for alcohol and nicotine). Analyses revealed that more lifetime cannabis use was associated with a higher BMI and greater likelihood of being overweight/obese. Interactions between DM and cannabis use on BMI were not significant, and DM was not directly associated with BMI. Our findings suggest that among adolescents, cannabis use is associated with a greater BMI regardless of DM abilities and this association is not accounted for by other potential factors, including depression, alcohol use, nicotine use, race, ethnicity, or IQ. (JINS, 2016, 22, 944-949).

Dinner rituals that correlate with child and adult BMI.

PubMed

Wansink, Brian; van Kleef, Ellen

2014-05-01

What predicts whether a child will be at risk for obesity? Whereas past research has focused on foods, eating habits, feeding styles, and family meal patterns, this study departs from a food-centric approach to examine how various dinner rituals might influence the BMIs of children and adults. In this study of 190 parents (BMI = 29.1 ± 7.2) and 148 children (BMI = 20.3 ± 4.4), the relationship between their BMIs and everyday family dinner rituals was examined using both correlation and regression analysis (controlled for educational level of parents). Families who frequently ate dinner in the kitchen or dining room had significantly lower BMIs for both adults (r = -0.31) and children (r = -0.24) compared to families who ate elsewhere. Additionally, helping cook dinner was associated with higher BMI for girls (r = 0.26), and remaining at the table until everyone is finished with eating was associated with lower BMI for boys (r = -0.31). Dinner tables may be one place where social support and family involvement meet-both of which relate to the BMI of children as well as parents. Family meals and their rituals might be an underappreciated battleground to fight obesity. Copyright © 2013 The Obesity Society.

Why are there race/ethnic differences in adult body mass index-adiposity relationships? A quantitative critical review.

PubMed

Heymsfield, S B; Peterson, C M; Thomas, D M; Heo, M; Schuna, J M

2016-03-01

Body mass index (BMI) is now the most widely used measure of adiposity on a global scale. Nevertheless, intense discussion centers on the appropriateness of BMI as a phenotypic marker of adiposity across populations differing in race and ethnicity. BMI-adiposity relations appear to vary significantly across race/ethnic groups, but a collective critical analysis of these effects establishing their magnitude and underlying body shape/composition basis is lacking. Accordingly, we systematically review the magnitude of these race-ethnic differences across non-Hispanic (NH) white, NH black and Mexican American adults, their anatomic body composition basis and potential biologically linked mechanisms, using both earlier publications and new analyses from the US National Health and Nutrition Examination Survey. Our collective observations provide a new framework for critically evaluating the quantitative relations between BMI and adiposity across groups differing in race and ethnicity; reveal new insights into BMI as a measure of adiposity across the adult age-span; identify knowledge gaps that can form the basis of future research and create a quantitative foundation for developing BMI-related public health recommendations. © 2015 World Obesity.

Impact of non-physician health professionals' BMI on obesity care and beliefs.

PubMed

Bleich, Sara N; Bandara, Sachini; Bennett, Wendy L; Cooper, Lisa A; Gudzune, Kimberly A

2014-12-01

Examine the impact of non-physician health professional body mass index (BMI) on obesity care, self-efficacy, and perceptions of patient trust in weight loss advice. A national cross-sectional Internet-based survey of 500 US non-physician health professionals specializing in nutrition, nursing, behavioral/mental health, exercise, and pharmacy collected between January 20 and February 5, 2014 was analyzed. Normal-BMI professionals were more likely than overweight/obese professionals to report success in helping patients achieve clinically significant weight loss (52% vs. 29%, P = 0.01). No differences by health professional BMI about the appropriate patient body weight for weight-related care (initiate weight loss discussions and success in helping patients lose weight), confidence in ability to help patients lose weight, or in perceived patient trust in their advice were observed. Most health professionals (71%) do not feel successful in helping patients lose weight until they are morbidly obese, regardless of BMI. Normal-BMI non-physician health professionals report being more successful than overweight and obese health professionals at helping obese patients lose weight. More research is needed to understand how to improve self-efficacy for delivering obesity care, particularly among overweight and class I obese patients. © 2014 The Obesity Society.

The Role of BMI1 in CRPC

DTIC Science & Technology

2016-10-01

with PTC209 and infected by BMI1 adenovirus (or control virus) for 24 hours. Post 8-hour 20µM MG132 treatment, immunoprecipitation was performed using...INVESTIGATOR: Qi Cao CONTRACTING ORGANIZATION: METHODIST HOSPITAL RESEARCH INSTITUTE...valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE October 2016 2. REPORT TYPE Annual 3. DATES

Maternal Pre-Pregnancy Body Mass Index and Offspring Temperament and Behavior at 1 and 2 Years of Age

ERIC Educational Resources Information Center

Van Lieshout, Ryan J.; Schmidt, Louis A.; Robinson, Monique; Niccols, Alison; Boyle, Michael H.

2013-01-01

Recent research suggests that fetal exposure to increased maternal body mass index (BMI) during pregnancy may be associated with psychopathology later in life. When this link first emerges, and if it is due to intrauterine exposures or confounding variables is not known. We therefore assessed associations between maternal pre-pregnancy BMI and:…

The Effect of Regular Breakfast on Body Mass Index in 9- to 10-Year-Old Czech Children

ERIC Educational Resources Information Center

Klimesova, Iva; Miklankova, Ludmila; Stelzer, Jiri; Ernest, James

2016-01-01

Background: Eating habits play a crucial role in weight control management; however, little research has examined whether frequency of breakfast consumption influences body mass index (BMI) in middle childhood. Purpose: The purpose of this study was to (a) determine the relationship between BMI and the frequency of breakfast consumption, (b)…

Anthropometrics to Identify Overweight Children at Most Risk for the Development of Cardiometabolic Disease.

PubMed

Labyak, Corinne A; Janicke, David M; Lim, Crystal S; Colee, James; Mathews, Anne E

2013-12-01

Sagittal abdominal diameter (SAD) is a novel anthropometric that correlates more strongly with visceral adipose tissue (VAT) and cardiometabolic disease risk in adults compared with body mass index (BMI). However, little research has evaluated this measurement in children. To evaluate SAD as a measure of cardiometabolic risk compared with other anthropometrics in overweight/obese children. This study was a cross-sectional subset analysis of 8- to 12-year-old overweight/ obese children. SAD was compared to BMI, waist circumference (WC), BMI z -score, and percent body fat to determine which measurement was most closely associated with cardiometabolic risk factors. A total cardiometabolic risk score comprising all biochemical markers and blood pressure was also compared to these same anthropometrics. Overweight/obese children (n = 145, mean age 10 ± 1.4 years, mean BMI percentile 97.9 ± 0.02) were included in the analysis. SAD correlated with the greatest number of biochemical markers/blood pressure values including triglycerides ( r = .18, P = .03), HgbA1c ( r = .21, P = .01), and systolic blood pressure ( r = .38, P < .0001). SAD was more strongly correlated to total risk score ( r = .25, P = .002) than WC ( r = .22, P = .006), BMI ( r = .17, P = .04), BMI- z ( r = .18, P = .03), and percent body fat ( r = .18, P = .03). This is the first study to evaluate SAD in overweight/obese American children as a marker of cardiometabolic disease risk. The results suggest a slightly stronger correlation between SAD and cardiometabolic risk factors in overweight/obese children; however, all correlations were weak. As this was a pilot study, additional research is needed prior to recommending the use of this measurement in clinical practice.

Poverty, Sprawl, and Restaurant Types Influence Body Mass Index of Residents in California Counties

PubMed Central

Gregson, Jennifer

2011-01-01

Objectives. This article examines the relationships between structural poverty (the proportion of people in a county living at ≤130% of the federal poverty level [FPL]), urban sprawl, and three types of restaurants (grouped as fast food, chain full service, and independent full service) in explaining body mass index (BMI) of individuals. Methods. Relationships were tested with two-tiered hierarchical models. Individual-level data, including the outcome variable of calculated BMI, were from the 2005, 2006, and 2007 California Behavioral Risk Factor Surveillance Survey (n=14,205). County-level data (n=33) were compiled from three sources. The 2000 U.S. Census provided the proportion of county residents living at ≤130% of FPL and county demographic descriptors. The sprawl index used came from the Smart Growth America Project. Fast-food, full-service chain, and full-service independently owned restaurants as proportions of the total retail food environment were constructed from a commercially available market research database from 2004. Results. In the analysis, county-level demographic characteristics lost significance and poverty had a consistent, robust association on BMI (p<0.001). Sprawl demonstrated an additional, complementary association to county poverty (p<0.001). Independent restaurants had a large, negative association to BMI (p<0.001). The coefficients for chain and fast-food restaurants were large and positive (p≤0.001), indicating that as the proportion of these restaurants in a county increases, so does BMI. Conclusions. This study demonstrates the important role of county poverty and urban sprawl toward understanding environmental influences on BMI. Using three categories of restaurants demonstrates different associations of full-service chain and independent restaurants, which are often combined in other research. PMID:21563722

The Healthy Fitness Zone Continuum Score as a Measure of Change in Body Mass Index of School-Aged Children and Adolescents, Georgia, 2012-2014.

PubMed

Saint-Maurice, Pedro F; Welk, Gregory J; Bai, Yang

The FitnessGram Healthy Fitness Zone continuum (HFZc) score reflects the relative difference of a person's body mass index (BMI) from the established FitnessGram standard. As such, it may provide added utility for public health programming and research on obesity among school-aged children and adolescents. We used the standard BMI Z (BMIz) score and the alternative HFZc score to describe changes in BMI of school-aged children and adolescents in Georgia over time. We compiled 2012-2014 BMI data from the Georgia FitnessGram database. The sample included 162 992 boys and 141 711 girls enrolled in 239 schools from a large urban district in Georgia. We analyzed trends in BMIz and HFZc scores separately for normal-weight, overweight, and obese categories for school-aged children and adolescents using hierarchical linear models. From 2012 to 2014, the BMIz score shifted favorably in up to 40.7% (2052/5047) of normal-weight, 51.0% (758/1485) of overweight, and 52.8% (5430/10 279) of obese students. We also found favorable shifts in HFZc score in up to 69.8% (105 831/151 739) of normal-weight, 78.3% (3605/4603) of overweight, and 80.8% (8305/10 279) of obese students. Compared with the BMIz score, the HFZc score may be a better indicator of favorable changes in BMI over time among school-aged children and adolescents with different baseline BMI levels, making it potentially valuable for use in individualized assessments, school programs, obesity research, and public health curriculum and policy development.

Poverty, sprawl, and restaurant types influence body mass index of residents in California counties.

PubMed

Gregson, Jennifer

2011-01-01

This article examines the relationships between structural poverty (the proportion of people in a county living at < or =130% of the federal poverty level [FPL]), urban sprawl, and three types of restaurants (grouped as fast food, chain full service, and independent full service) in explaining body mass index (BMI) of individuals. Relationships were tested with two-tiered hierarchical models. Individual-level data, including the outcome variable of calculated BMI, were from the 2005, 2006, and 2007 California Behavioral Risk Factor Surveillance Survey (n = 14,205). County-level data (n = 33) were compiled from three sources. The 2000 U.S. Census provided the proportion of county residents living at < or = 130% of FPL and county demographic descriptors. The sprawl index used came from the Smart Growth America Project. Fast-food, full-service chain, and full-service independently owned restaurants as proportions of the total retail food environment were constructed from a commercially available market research database from 2004. In the analysis, county-level demographic characteristics lost significance and poverty had a consistent, robust association on BMI (p < 0.001). Sprawl demonstrated an additional, complementary association to county poverty (p < 0.001). Independent restaurants had a large, negative association to BMI (p < 0.001). The coefficients for chain and fast-food restaurants were large and positive (p < or = 0.001), indicating that as the proportion of these restaurants in a county increases, so does BMI. This study demonstrates the important role of county poverty and urban sprawl toward understanding environmental influences on BMI. Using three categories of restaurants demonstrates different associations of full-service chain and independent restaurants, which are often combined in other research.

Black breast cancer survivors experience greater upper extremity disability.

PubMed

Dean, Lorraine T; DeMichele, Angela; LeBlanc, Mously; Stephens-Shields, Alisa; Li, Susan Q; Colameco, Chris; Coursey, Morgan; Mao, Jun J

2015-11-01

Over one-third of breast cancer survivors experience upper extremity disability. Black women present with factors associated with greater upper extremity disability, including: increased body mass index (BMI), more advanced disease stage at diagnosis, and varying treatment type compared with Whites. No prior research has evaluated the relationship between race and upper extremity disability using validated tools and controlling for these factors. Data were drawn from a survey study among 610 women with stage I-III hormone receptor positive breast cancer. The disabilities of the arm, shoulder and hand (QuickDASH) is an 11-item self-administered questionnaire that has been validated for breast cancer survivors to assess global upper extremity function over the past 7 days. Linear regression and mediation analysis estimated the relationships between race, BMI and QuickDASH score, adjusting for demographics and treatment types. Black women (n = 98) had 7.3 points higher average QuickDASH scores than White (n = 512) women (p < 0.001). After adjusting for BMI, age, education, cancer treatment, months since diagnosis, and aromatase inhibitor status, Black women had an average 4-point (95 % confidence interval 0.18-8.01) higher QuickDASH score (p = 0.04) than White women. Mediation analysis suggested that BMI attenuated the association between race and disability by 40 %. Even several years post-treatment, Black breast cancer survivors had greater upper extremity disability, which was partially mediated by higher BMIs. Close monitoring of high BMI Black women may be an important step in reducing disparities in cancer survivorship. More research is needed on the relationship between race, BMI, and upper extremity disability.

Parental Feeding Style and Pediatric Obesity in Latino Families.

PubMed

Maliszewski, Genevieve; Gillette, Meredith Dreyer; Brown, Chris; Cowden, John D

2017-06-01

Pediatric obesity has become an epidemic in the United States. Previous research has shown that parenting factors related to feeding style affect child weight and that Latino families are especially at risk for pediatric obesity. The goal of the current study was to evaluate the relationship between parental feeding style and child body mass index (BMI) in Latino families. Latino parents of children between the ages of 2 and 8 ( N = 124) completed a survey on parental feeding styles, acculturation, and demographics. The outcome variable was child BMI. Among respondents, 89% were mothers, 72% were overweight or obese, and 40% reported an indulgent feeding style. Children had a mean age of 59 months ( SD = 23.8) and a mean BMI z score of 0.77 ( SD = 1.14). A demanding parental feeding style was associated with lower child BMI z score, r = -.179, p < .05, and higher acculturation level, r = .213, p < .05. Findings from the current study can be used to inform health care practitioners of the need to use culturally sensitive interventions that consider parents' feeding behaviors. Future research is warranted in the area of ethnic variations of parenting and how these affect feeding and obesity in this highly vulnerable population.

Effect of body mass index and albumin on mortality rates for adult African-American hemodialysis patients.

PubMed

Feingold, Edna; Adams, Judy; Penprase, Barbara; Tubie, Boniface

2015-11-01

The purpose of this retrospective descriptive study was to investigate if body mass index (BMI) and serum albumin (SA) impacted mortality rates in adult African-American patients on hemodialysis (HD). Records of 204 patients on HD (N = 204) from a clinic in the metropolitan Detroit area were examined for the period January 1, 2007-December 31, 2012 to determine the relationship of BMI and SA on mortality rates in this population. Logistics regression was utilized to analyze the association of several risk factors (BMI and SA) on survival (mortality rates). Research findings from this study demonstrated that both undernourishment (being underweight; BMI < 23 kg/m(2) ) and hypoalbuminemia (<3.2g/dL) were strong predictors of death in patients on HD. However, obesity provided a survival advantage for adult African-American patients on HD (p = .030). Patients with higher SA levels also survived longer (p < .001). Advanced practice nurses (APNs) working with adult African-American patients on HD could work on developing targeted nutritional interventions to maintain higher SAs and BMIs while awaiting the results of further research in this area. ©2015 American Association of Nurse Practitioners.

Obesity in pediatric trauma.

PubMed

Witt, Cordelie E; Arbabi, Saman; Nathens, Avery B; Vavilala, Monica S; Rivara, Frederick P

2017-04-01

The implications of childhood obesity on pediatric trauma outcomes are not clearly established. Anthropomorphic data were recently added to the National Trauma Data Bank (NTDB) Research Datasets, enabling a large, multicenter evaluation of the effect of obesity on pediatric trauma patients. Children ages 2 to 19years who required hospitalization for traumatic injury were identified in the 2013-2014 NTDB Research Datasets. Age and gender-specific body mass indices (BMI) were calculated. Outcomes included injury patterns, operative procedures, complications, and hospital utilization parameters. Data from 149,817 pediatric patients were analyzed; higher BMI percentiles were associated with significantly more extremity injuries, and fewer injuries to the head, abdomen, thorax and spine (p values <0.001). On multivariable analysis, higher BMI percentiles were associated with significantly increased likelihood of death, deep venous thrombosis, pulmonary embolus and pneumonia; although there was no difference in risk of overall complications. Obese children also had significantly longer lengths of stay and more frequent ventilator requirement. Among children admitted after trauma, increased BMI percentile is associated with increased risk of death and potentially preventable complications. These findings suggest that obese children may require different management than nonobese counterparts to prevent complications. Level III; prognosis study. Copyright © 2017 Elsevier Inc. All rights reserved.

Parent predictors of child weight change in family based behavioral obesity treatment.

PubMed

Boutelle, Kerri N; Cafri, Guy; Crow, Scott J

2012-07-01

Family based behavioral treatment for overweight and obese children includes parenting skills targeting the modification of child eating and activity change. The purpose of this study was to examine parenting skills and parent weight change as predictors of child weight change in a sample of 80 parent/child dyads who were enrolled in a family based behavioral weight loss program for childhood obesity. Eighty overweight and obese children and their parents who enrolled in treatment in two sites were included in the study. Variables included those related to parent modeling (parent BMI), home food environment, parenting (parent and child report), and demographics. Results suggested that parent BMI change was a significant predictor of child weight, in that a reduction of 1 BMI unit in the parent was associated with a 0.255 reduction in child BMI. None of the other variables were significant in the final model. This study is consistent with other research showing that parent weight change is a key contributor to child weight change in behavioral treatment for childhood obesity. Researchers and clinicians should focus on encouraging parents to lose weight to assist their overweight and obese child in weight management.

Ultra-low-cost 3D gaze estimation: an intuitive high information throughput compliment to direct brain-machine interfaces

NASA Astrophysics Data System (ADS)

Abbott, W. W.; Faisal, A. A.

2012-08-01

Eye movements are highly correlated with motor intentions and are often retained by patients with serious motor deficiencies. Despite this, eye tracking is not widely used as control interface for movement in impaired patients due to poor signal interpretation and lack of control flexibility. We propose that tracking the gaze position in 3D rather than 2D provides a considerably richer signal for human machine interfaces by allowing direct interaction with the environment rather than via computer displays. We demonstrate here that by using mass-produced video-game hardware, it is possible to produce an ultra-low-cost binocular eye-tracker with comparable performance to commercial systems, yet 800 times cheaper. Our head-mounted system has 30 USD material costs and operates at over 120 Hz sampling rate with a 0.5-1 degree of visual angle resolution. We perform 2D and 3D gaze estimation, controlling a real-time volumetric cursor essential for driving complex user interfaces. Our approach yields an information throughput of 43 bits s-1, more than ten times that of invasive and semi-invasive brain-machine interfaces (BMIs) that are vastly more expensive. Unlike many BMIs our system yields effective real-time closed loop control of devices (10 ms latency), after just ten minutes of training, which we demonstrate through a novel BMI benchmark—the control of the video arcade game ‘Pong’.

Design and validation of a real-time spiking-neural-network decoder for brain-machine interfaces

NASA Astrophysics Data System (ADS)

Dethier, Julie; Nuyujukian, Paul; Ryu, Stephen I.; Shenoy, Krishna V.; Boahen, Kwabena

2013-06-01

Objective. Cortically-controlled motor prostheses aim to restore functions lost to neurological disease and injury. Several proof of concept demonstrations have shown encouraging results, but barriers to clinical translation still remain. In particular, intracortical prostheses must satisfy stringent power dissipation constraints so as not to damage cortex. Approach. One possible solution is to use ultra-low power neuromorphic chips to decode neural signals for these intracortical implants. The first step is to explore in simulation the feasibility of translating decoding algorithms for brain-machine interface (BMI) applications into spiking neural networks (SNNs). Main results. Here we demonstrate the validity of the approach by implementing an existing Kalman-filter-based decoder in a simulated SNN using the Neural Engineering Framework (NEF), a general method for mapping control algorithms onto SNNs. To measure this system’s robustness and generalization, we tested it online in closed-loop BMI experiments with two rhesus monkeys. Across both monkeys, a Kalman filter implemented using a 2000-neuron SNN has comparable performance to that of a Kalman filter implemented using standard floating point techniques. Significance. These results demonstrate the tractability of SNN implementations of statistical signal processing algorithms on different monkeys and for several tasks, suggesting that a SNN decoder, implemented on a neuromorphic chip, may be a feasible computational platform for low-power fully-implanted prostheses. The validation of this closed-loop decoder system and the demonstration of its robustness and generalization hold promise for SNN implementations on an ultra-low power neuromorphic chip using the NEF.

The relation of weight suppression and BMI to bulimic symptoms.

PubMed

Butryn, Meghan L; Juarascio, Adrienne; Lowe, Michael R

2011-11-01

High levels of weight suppression have been associated with greater binge eating and weight gain as well as poorer treatment outcome in bulimia nervosa. This study examined the relationship between weight suppression and bulimia nervosa symptoms and explored how weight suppression might interact with body mass index (BMI) in accounting for level of symptomatology at presentation for treatment. Participants were 64 women with threshold or sub-threshold bulimia nervosa. A clinical interview assessed binge eating and purging. Weight suppression and the interaction between BMI and weight suppression predicted frequency of binge eating such that participants with low BMI and high weight suppression engaged in the most binge eating. High levels of weight suppression also predicted more frequent purging. Additional research is warranted to examine mediators of these relationships. Copyright © 2010 Wiley Periodicals, Inc.

Impact of Masked Replacement of Sugar-Sweetened with Sugar-Free Beverages on Body Weight Increases with Initial BMI: Secondary Analysis of Data from an 18 Month Double-Blind Trial in Children.

PubMed

Katan, Martijn B; de Ruyter, Janne C; Kuijper, Lothar D J; Chow, Carson C; Hall, Kevin D; Olthof, Margreet R

2016-01-01

Substituting sugar-free for sugar-sweetened beverages reduces weight gain. This effect may be more pronounced in children with a high body mass index (BMI) because their sensing of kilocalories might be compromised. We investigated the impact of sugar-free versus sugary drinks separately in children with a higher and a lower initial BMI z score, and predicted caloric intakes and degree of compensation in the two groups. This is a secondary, explorative analysis of our double-blind randomized controlled trial (RCT) which showed that replacement of one 250-mL sugary drink per day by a sugar-free drink for 18 months significantly reduced weight gain. In the 477 children who completed the trial, mean initial weights were close to the Dutch average. Only 16% were overweight and 3% obese. Weight changes were expressed as BMI z-score, i.e. as standard deviations of the BMI distribution per age and sex group. We designated the 239 children with an initial BMI z-score below the median as 'lower BMI' and the 238 children above the median as 'higher BMI'. The difference in caloric intake from experimental beverages between treatments was 86 kcal/day both in the lower and in the higher BMI group. We used a multiple linear regression and the coefficient of the interaction term (initial BMI group times treatment), indicated whether children with a lower BMI responded differently from children with a higher BMI. Statistical significance was defined as p ≤ 0.05. Relative to the sugar sweetened beverage, consumption of the sugar-free beverage for 18 months reduced the BMI z-score by 0.05 SD units within the lower BMI group and by 0.21 SD within the higher BMI group. Body weight gain was reduced by 0.62 kg in the lower BMI group and by 1.53 kg in the higher BMI group. Thus the treatment reduced the BMI z-score by 0.16 SD units more in the higher BMI group than in the lower BMI group (p = 0.04; 95% CI -0.31 to -0.01). The impact of the intervention on body weight gain differed by 0.90 kg between BMI groups (p = 0.09; 95% CI -1.95 to 0.14). In addition, we used a physiologically-based model of growth and energy balance to estimate the degree to which children had compensated for the covertly removed sugar kilocalories by increasing their intake of other foods. The model predicts that children with a lower BMI had compensated 65% (95% CI 28 to 102) of the covertly removed sugar kilocalories, whereas children with a higher BMI compensated only 13% (95% CI -37 to 63). The children with a BMI above the median might have a reduced tendency to compensate for changes in caloric intake. Differences in these subconscious compensatory mechanisms may be an important cause of differences in the tendency to gain weight. If further research bears this out, cutting down on the intake of sugar-sweetened drinks may benefit a large proportion of children, especially those who show a tendency to become overweight. ClinicalTrials.gov NCT00893529.

Body-mass index and all-cause mortality: individual-participant-data meta-analysis of 239 prospective studies in four continents.

PubMed

Global BMI Mortality Collaboration; Di Angelantonio, Emanuele; Bhupathiraju, Shilpa; Wormser, David; Gao, Pei; Kaptoge, Stephen; Berrington de Gonzalez, Amy; Cairns, Benjamin; Huxley, Rachel; Jackson, Chandra; Joshy, Grace; Lewington, Sarah; Manson, JoAnn; Murphy, Neil; Patel, Alpa; Samet, Jonathan; Woodward, Mark; Zheng, Wei; Zhou, Maigen; Bansal, Narinder; Barricarte, Aurelio; Carter, Brian; Cerhan, James; Smith, George; Fang, Xianghua; Franco, Oscar; Green, Jane; Halsey, Jim; Hildebrand, Janet; Jung, Keum; Korda, Rosemary; McLerran, Dale; Moore, Steven; O'Keeffe, Linda; Paige, Ellie; Ramond, Anna; Reeves, Gillian; Rolland, Betsy; Sacerdote, Carlotta; Sattar, Naveed; Sofianopoulou, Eleni; Stevens, June; Thun, Michael; Ueshima, Hirotsugu; Yang, Ling; Yun, Young; Willeit, Peter; Banks, Emily; Beral, Valerie; Chen, Zhengming; Gapstur, Susan; Gunter, Marc; Hartge, Patricia; Jee, Sun; Lam, Tai-Hing; Peto, Richard; Potter, John; Willett, Walter; Thompson, Simon; Danesh, John; Hu, Frank

2016-08-20

Overweight and obesity are increasing worldwide. To help assess their relevance to mortality in different populations we conducted individual-participant data meta-analyses of prospective studies of body-mass index (BMI), limiting confounding and reverse causality by restricting analyses to never-smokers and excluding pre-existing disease and the first 5 years of follow-up. Of 10 625 411 participants in Asia, Australia and New Zealand, Europe, and North America from 239 prospective studies (median follow-up 13·7 years, IQR 11·4-14·7), 3 951 455 people in 189 studies were never-smokers without chronic diseases at recruitment who survived 5 years, of whom 385 879 died. The primary analyses are of these deaths, and study, age, and sex adjusted hazard ratios (HRs), relative to BMI 22·5-<25·0 kg/m(2). All-cause mortality was minimal at 20·0-25·0 kg/m(2) (HR 1·00, 95% CI 0·98-1·02 for BMI 20·0-<22·5 kg/m(2); 1·00, 0·99-1·01 for BMI 22·5-<25·0 kg/m(2)), and increased significantly both just below this range (1·13, 1·09-1·17 for BMI 18·5-<20·0 kg/m(2); 1·51, 1·43-1·59 for BMI 15·0-<18·5) and throughout the overweight range (1·07, 1·07-1·08 for BMI 25·0-<27·5 kg/m(2); 1·20, 1·18-1·22 for BMI 27·5-<30·0 kg/m(2)). The HR for obesity grade 1 (BMI 30·0-<35·0 kg/m(2)) was 1·45, 95% CI 1·41-1·48; the HR for obesity grade 2 (35·0-<40·0 kg/m(2)) was 1·94, 1·87-2·01; and the HR for obesity grade 3 (40·0-<60·0 kg/m(2)) was 2·76, 2·60-2·92. For BMI over 25·0 kg/m(2), mortality increased approximately log-linearly with BMI; the HR per 5 kg/m(2) units higher BMI was 1·39 (1·34-1·43) in Europe, 1·29 (1·26-1·32) in North America, 1·39 (1·34-1·44) in east Asia, and 1·31 (1·27-1·35) in Australia and New Zealand. This HR per 5 kg/m(2) units higher BMI (for BMI over 25 kg/m(2)) was greater in younger than older people (1·52, 95% CI 1·47-1·56, for BMI measured at 35-49 years vs 1·21, 1·17-1·25, for BMI measured at 70-89 years; pheterogeneity<0·0001), greater in men than women (1·51, 1·46-1·56, vs 1·30, 1·26-1·33; pheterogeneity<0·0001), but similar in studies with self-reported and measured BMI. The associations of both overweight and obesity with higher all-cause mortality were broadly consistent in four continents. This finding supports strategies to combat the entire spectrum of excess adiposity in many populations. UK Medical Research Council, British Heart Foundation, National Institute for Health Research, US National Institutes of Health. Copyright © 2016 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC-BY license. Published by Elsevier Ltd.. All rights reserved.

Gender Difference in Aerobic Capacity and the Contribution by Body Composition and Haemoglobin Concentration: A Study in Young Indian National Hockey Players

PubMed Central

Kailashiya, Jyotsna

2016-01-01

Introduction Although gender difference in aerobic capacity is known, the contributing factors have been researched seldom. Aim To investigate the gender gap and the contribution by percentage Body Fat (BF), Body Mass Index (BMI) and haemoglobin concentration Hb. Materials and Methods The study was conducted on 30 (17 males, 13 females) training status matched young hockey players. Healthy players who were playing upto national level competition were included. BW (Body Weight), BF, BMI, LBM (Lean Body Mass), rHR (restring Heart Rate), HRR (Heart Rate Recovery), Hb, a/rVO2max (absolute/relative), a/rPWC (Physical Work Capacity) and RMR (Resting Metabolic Rate) were measured and analysed. Results There was significant gender difference in the measured parameters. Difference in a/rVO2max remained significant even after controlling for BF, BMI and Hb. Multiple regression and correlation analysis revealed gender difference in VO2max/LBM was due to: BMI(31.91%)>BF(27.60%)>Hb(9.91%). BMI also significantly contributed 3.66% of VO2max/LBM variance, independent of that by gender. Difference in RMR was mainly related to LBM, BF and BMI. Conclusion The study provided an understanding for gender gap in aerobic capacity. Differences in BMI & BF were one of the main reasons. PMID:28050360

Body mass index is not a clinically meaningful predictor of patient reported outcomes of primary hip replacement surgery: prospective cohort study.

PubMed

Judge, A; Batra, R N; Thomas, G E; Beard, D; Javaid, M K; Murray, D W; Dieppe, P A; Dreinhoefer, K E; Peter-Guenther, K; Field, R; Cooper, C; Arden, N K

2014-03-01

To describe whether body mass index (BMI) is a clinically meaningful predictor of patient reported outcomes following primary total hip replacement (THR) surgery. Combined data from prospective cohort studies. We obtained information from four cohorts of patients receiving primary THR for osteoarthritis: Exeter Primary Outcomes Study (EPOS) (n = 1431); EUROHIP (n = 1327); Elective Orthopaedic Centre (n = 2832); and St. Helier (n = 787). The exposure of interest was pre-operative BMI. Confounding variables included: age, sex, SF-36 mental health, comorbidities, fixed flexion, analgesic use, college education, OA in other joints, expectation of less pain, radiographic K&L grade, ASA grade, years of hip pain. The primary outcome was the Oxford Hip Score (OHS). Regression models describe the association of BMI on outcome adjusting for all confounders. For a 5-unit increase in BMI, the attained 12-month OHS decreases by 0.78 points 95%CI (0.27-1.28), P-value 0.001. Compared to people of normal BMI (20-25), those in the obese class II (BMI 35-40) would have a 12-month OHS that is 2.34 points lower. Although statistically significant this effect is small and not clinically meaningful in contrast to the substantial change in OHS seen across all BMI groupings. In obese class II patients achieved a 22.2 point change in OHS following surgery. Patients achieved substantial change in OHS after THR across all BMI categories, which greatly outweighs the small difference in attained post-operative score. The findings suggest BMI should not present a barrier to access THR in terms of PROMs. Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

An evaluation of the impact of donor BMI on survival and post-transplant obesity in pediatric liver transplant recipients

PubMed Central

Perito, Emily Rothbaum; Rhee, Sue; Glidden, Dave; Roberts, John Paul; Rosenthal, Philip

2012-01-01

Introduction In adult liver transplant recipients, donor BMI is associated with post-transplant obesity but not graft or patient survival. Given the U.S. obesity epidemic and already-limited supply of liver donors, clarifying whether donor BMI affects pediatric outcomes is important. Methods UNOS data on pediatric U.S. liver transplants 1990-2010 was evaluated. Data on transplants 2004-2010 (n=3788) was used for survival analysis with Kaplan-Meier and Cox proportional hazards models and for post-transplant obesity analysis with generalized estimating equations. Results For children receiving adult donor livers, donor BMI 25-35 kg/m2 was not associated with graft or patient survival in univariate or multivariate analyses. Donor BMI>35 kg/m2 increased the risk of graft loss (HR 2.54, 95%CI 1.29-5.01, p=0.007) and death (HR 3.56, 95%CI 1.64-7.72, p=0.001). For pediatric donors, donor BMI was not associated with graft loss or mortality in univariate or multivariate analysis. Donor overweight/obesity was not a risk factor for post-transplant obesity. Conclusions Overweight/obesity is common among liver transplant donors. This analysis suggests that for adult donors, BMI 25-35 should not by itself be a contraindication to liver donation. Severe obesity (BMI>35) in adult donors increased the risk of graft loss and mortality, even after adjustment for recipient, donor, and transplant risk factors. Post-transplant obesity was not associated with donor BMI in this analysis. Further research is needed to clarify the impact of donor obesity on pediatric liver transplant recipients. PMID:22467594

Examining weight suppression as a predictor of eating disorder symptom trajectories in anorexia nervosa.

PubMed

Bodell, Lindsay P; Racine, Sarah E; Wildes, Jennifer E

2016-08-01

Research in individuals with bulimia nervosa has highlighted the clinical significance of weight suppression (WS), defined as the difference between one's highest and current weight. More recently, studies have suggested that WS also may play a role in symptom maintenance and weight gain during treatment in anorexia nervosa (AN) and that the influence of WS on AN outcomes may depend on an individual's body mass index (BMI). However, no study has investigated whether WS or the interaction between WS and BMI is associated with the longer-term course of eating pathology following treatment discharge in patients with AN. The current study examined a sample of females with AN (N = 180) who completed interviews and self-report questionnaires at discharge from intensive treatment and at 3, 6, and 12-months after discharge. Latent growth curve models tested whether WS, BMI, or the WS by BMI interaction significantly predicted the trajectory of eating disorder symptoms (i.e., Eating Disorder Examination global score, BMI, frequency of loss of control eating, frequency of purging) over the year following discharge. WS at discharge predicted change in BMI, and the interaction between WS and BMI predicted growth in eating disorder severity and purging frequency over time. Neither WS nor its interaction with BMI predicted growth in loss of control eating frequency. Results provide further support for the clinical significance of WS in AN symptom maintenance, but suggest that the influence of WS likely depends on an individual's BMI as well as the outcome being measured. © 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2016; 49:753-763). © 2016 Wiley Periodicals, Inc.

Descriptive Characteristics and Health Outcomes of the Food by Prescription Nutrition Supplementation Program for Adults Living with HIV in Nyanza Province, Kenya

PubMed Central

Nagata, Jason M.; Cohen, Craig R.; Young, Sera L.; Wamuyu, Catherine; Armes, Mary N.; Otieno, Benard O.; Leslie, Hannah H.; Dandu, Madhavi; Stewart, Christopher C.; Bukusi, Elizabeth A.; Weiser, Sheri D.

2014-01-01

Background The clinical effects and potential benefits of nutrition supplementation interventions for persons living with HIV remain largely unreported, despite awareness of the multifaceted relationship between HIV infection and nutrition. We therefore examined descriptive characteristics and nutritional outcomes of the Food by Prescription (FBP) nutrition supplementation program in Nyanza Province, Kenya. Methods Demographic, health, and anthropometric data were gathered from a retrospective cohort of 1,017 non-pregnant adult patients who enrolled into the FBP program at a Family AIDS Care and Education Services (FACES) site in Nyanza Province between July 2009 and July 2011. Our primary outcome was FBP treatment success defined as attainment of BMI>20, and we used Cox proportional hazards to assess socio-demographic and clinical correlates of FBP treatment success. Results Mean body mass index was 16.4 upon enrollment into the FBP program. On average, FBP clients gained 2.01 kg in weight and 0.73 kg/m2 in BMI over follow-up (mean 100 days), with the greatest gains among the most severely undernourished (BMI <16) clients (p<0.001). Only 13.1% of clients attained a BMI>20, though 44.5% achieved a BMI increase ≥0.5. Greater BMI at baseline, younger age, male gender, and not requiring highly active antiretroviral therapy (HAART) were associated with a higher rate of attainment of BMI>20. Conclusion This study reports significant gains in weight and BMI among patients enrolled in the FBP program, though only a minority of patients achieved stated programmatic goals of BMI>20. Future research should include well-designed prospective studies that examine retention, exit reasons, mortality outcomes, and long-term sustainability of nutrition supplementation programs for persons living with HIV. PMID:24646586

Descriptive characteristics and health outcomes of the food by prescription nutrition supplementation program for adults living with HIV in Nyanza Province, Kenya.

PubMed

Nagata, Jason M; Cohen, Craig R; Young, Sera L; Wamuyu, Catherine; Armes, Mary N; Otieno, Benard O; Leslie, Hannah H; Dandu, Madhavi; Stewart, Christopher C; Bukusi, Elizabeth A; Weiser, Sheri D

2014-01-01

The clinical effects and potential benefits of nutrition supplementation interventions for persons living with HIV remain largely unreported, despite awareness of the multifaceted relationship between HIV infection and nutrition. We therefore examined descriptive characteristics and nutritional outcomes of the Food by Prescription (FBP) nutrition supplementation program in Nyanza Province, Kenya. Demographic, health, and anthropometric data were gathered from a retrospective cohort of 1,017 non-pregnant adult patients who enrolled into the FBP program at a Family AIDS Care and Education Services (FACES) site in Nyanza Province between July 2009 and July 2011. Our primary outcome was FBP treatment success defined as attainment of BMI>20, and we used Cox proportional hazards to assess socio-demographic and clinical correlates of FBP treatment success. Mean body mass index was 16.4 upon enrollment into the FBP program. On average, FBP clients gained 2.01 kg in weight and 0.73 kg/m2 in BMI over follow-up (mean 100 days), with the greatest gains among the most severely undernourished (BMI <16) clients (p<0.001). Only 13.1% of clients attained a BMI>20, though 44.5% achieved a BMI increase ≥0.5. Greater BMI at baseline, younger age, male gender, and not requiring highly active antiretroviral therapy (HAART) were associated with a higher rate of attainment of BMI>20. This study reports significant gains in weight and BMI among patients enrolled in the FBP program, though only a minority of patients achieved stated programmatic goals of BMI>20. Future research should include well-designed prospective studies that examine retention, exit reasons, mortality outcomes, and long-term sustainability of nutrition supplementation programs for persons living with HIV.

Assessment of under nutrition of Bangladeshi adults using anthropometry: can body mass index be replaced by mid-upper-arm-circumference?

PubMed

Sultana, Tania; Karim, Md Nazmul; Ahmed, Tahmeed; Hossain, Md Iqbal

2015-01-01

Body-mass-index (BMI) is widely accepted as an indicator of nutritional status in adults. Mid-upper-arm-circumference (MUAC) is another anthropometric-measure used primarily among children. The present study attempted to evaluate the use of MUAC as a simpler alternative to BMI cut-off <18.5 to detect adult undernutrition, and thus to suggest a suitable cut-off value. A cross-sectional study in 650 adult attendants of the patients of Dhaka-Hospital, of the International Centre for Diarrheal Disease Research, Bangladesh (icddr,b) was conducted during 2012. Height, weight and MUAC of 260 male and 390 female aged 19-60 years were measured. Curve estimation was done to assess the linearity and correlation of BMI and MUAC. Sensitivity and specificity of MUAC against BMI<18.5 was determined. Separate Receiver-operating-characteristic (ROC) analyses were performed for male and female. Area under ROC curve and Youden's index were generated to aid selection of the most suitable cut-off value of MUAC for undernutrition. A value with highest Youden's index was chosen for cut-off. Our data shows strong significant positive correlation (linear) between MUAC and BMI, for males r = 0.81, (p<0.001) and for females r = 0.828, (p<0.001). MUAC cut-off <25.1 cm in males (AUC 0.930) and <23.9 cm in females (AUC 0.930) were chosen separately based on highest corresponding Youden's index. These values best correspond with BMI cut-off for under nutrition (BMI <18.5) in either gender. MUAC correlates closely with BMI. For the simplicity and easy to remember MUAC <25 cm for male and <24 cm for female may be considered as a simpler alternative to BMI cut-off <18.5 to detect adult undernutrition.

Is local or central adiposity more strongly associated with incident knee osteoarthritis than the body mass index in men or women?

PubMed

Culvenor, A G; Felson, D T; Wirth, W; Dannhauer, T; Eckstein, F

2018-05-25

To determine whether central (abdominal) or peripheral (thigh) adiposity measures are associated with incident radiographic knee osteoarthritis (RKOA) independent of body mass index (BMI) and whether their relation to RKOA was stronger than that of BMI. 161 Osteoarthritis Initiative (OAI) participants (62% female) with incident RKOA (Kellgren/Lawrence grade 0/1 at baseline, developing an osteophyte and joint space narrowing (JSN) grade ≥1 by year-4) were matched to 186 controls (58% female) without incident RKOA. Baseline waist-height-ratio (WHtR), and anatomical cross-sectional areas of thigh subcutaneous (SCF) and intermuscular fat (IMF) were measured, the latter using axial magnetic resonance images. Logistic regression assessed the relationship between each adiposity measure and incident RKOA before and after adjustment for BMI, and area under receiver operating characteristic curves (AUC) for each adiposity measure was compared to that of BMI using chi-squared tests. BMI, WHtR, subcutaneous fat (SCF) and IMF were all significantly associated with incident RKOA when analysed separately, with similar effect sizes (odds ratio range 1.30-1.53). After adjusting for BMI, odds ratios (ORs) for WHtR, SCF and IMF were attenuated and no longer statistically significant. No measure of central or peripheral adiposity was significantly more strongly associated with incident RKOA than BMI. Results were similar for men and women. Although both central (WHtR) and peripheral (SCF and IMF) adiposity were significantly associated with incident RKOA, neither was more strongly associated with incident RKOA than BMI. The simple measure of BMI appears sufficient to capture the elevated risk of RKOA associated with greater amounts of localised adiposity. Copyright © 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Do Brief Motivational Interventions Reduce Drinking Game Frequency in Mandated Students? An analysis of data from two randomized controlled trials

PubMed Central

Fernandez, Anne C.; Yurasek, Allison M.; Merrill, Jennifer E.; Miller, Mary Beth; Zamboanga, Byron L.; Carey, Kate B.; Borsari, Brian

2016-01-01

Purpose College students frequently engage in drinking games (DG) and experience a variety of consequences as a result. It is currently unknown whether brief motivational interventions (BMI) that provide feedback on DG participation can reduce this high risk behavior. This study examined outcome data from two randomized clinical trials to examine whether BMIs facilitate change in DG frequency and how these changes may occur. Methods Mandated college students (Trial 1, N = 198, 46% female; Trial 2, N = 412; 32% female) were randomized to BMI or comparison control conditions. Hierarchical linear modeling (HLM) was used to compare the BMI and comparison groups to determine whether the BMI reduced DG participation over time. Percent change talk (PCT) during the discussion of DG during the session was examined as a predictor of change in DG frequency, and gender was examined as a moderator of treatment effects. Results Controlling for regular drinking frequency, participants who received a BMI did not significantly reduce their DG frequency relative to the comparison group in either sample, and the BMI was equally ineffective at reducing DG behavior for men and women. DG-related PCT during the BMI was associated with lower DG frequency at the second follow-up in both Trials. In Trial 1, PCT during the BMI was associated with less steep increases in DG frequency across the course of all follow-ups. Effects of PCT on DG behavior were not moderated by gender. Conclusions Findings did not support hypothesized reductions in DG participation following a BMI. Future research should explore whether targeted DG-specific interventions could reduce DG participation and the role of in-session client language in facilitating such change. PMID:27936818

The Association Between Racial and Gender Discrimination and Body Mass Index Among Residents Living in Lower-income Housing

PubMed Central

Shelton, Rachel C.; Puleo, Elaine; Bennett, Gary G.; McNeill, Lorna H.; Sorensen, Glorian; Emmons, Karen M.

2010-01-01

Background Research on the association between self-reported racial or gender discrimination and body mass index (BMI) has been limited and inconclusive to date, particularly among lower-income populations. Objectives The aim of the current study was to examine the association between self-reported racial and gender discrimination and BMI among a sample of adult residents living in 12 urban lower-income housing sites in Boston, Masschusetts (USA). Methods Baseline survey data were collected among 1,307 (weighted N=1907) study participants. For analyses, linear regression models with a cluster design were conducted using SUDAAN and SAS statistical software. Results Our sample was predominately Black (weighted n=956) and Hispanic (weighted n=857), and female (weighted n=1420), with a mean age of 49.3 (SE: .40) and mean BMI of 30.2 kg m−2 (SE: .19). Nearly 47% of participants reported ever experiencing racial discrimination, and 24.8% reported ever experiencing gender discrimination. In bivariate and multivariable linear regression models, no main effect association was found between either racial or gender discrimination and BMI. Conclusions While our findings suggest that self-reported discrimination is not a key determinant of BMI among lower-income housing residents, these results should be considered in light of study limitations. Future researchers may want to investigate this association among other relevant samples, and other social contextual and cultural factors should be explored to understand how they contribute to disparities. PMID:19769005

The association between racial and gender discrimination and body mass index among residents living in lower-income housing.

PubMed

Shelton, Rachel C; Puleo, Elaine; Bennett, Gary G; McNeill, Lorna H; Sorensen, Glorian; Emmons, Karen M

2009-01-01

Research on the association between self-reported racial or gender discrimination and body mass index (BMI) has been limited and inconclusive to date, particularly among lower-income populations. The aim of the current study was to examine the association between self-reported racial and gender discrimination and BMI among a sample of adult residents living in 12 urban lower-income housing sites in Boston, Masschusetts (USA). Baseline survey data were collected among 1,307 (weighted N = 1907) study participants. For analyses, linear regression models with a cluster design were conducted using SUDAAN and SAS statistical software. Our sample was predominately Black (weighted n = 956) and Hispanic (weighted n = 857), and female (weighted n = 1420), with a mean age of 49.3 (SE: .40) and mean BMI of 30.2 kg m(-2) (SE: .19). Nearly 47% of participants reported ever experiencing racial discrimination, and 24.8% reported ever experiencing gender discrimination. In bivariate and multivariable linear regression models, no main effect association was found between either racial or gender discrimination and BMI. While our findings suggest that self-reported discrimination is not a key determinant of BMI among lower-income housing residents, these results should be considered in light of study limitations. Future researchers may want to investigate this association among other relevant samples, and other social contextual and cultural factors should be explored to understand how they contribute to disparities.

Association of Pre-pregnancy BMI and Postpartum Weight Retention Before Second Pregnancy, Washington State, 2003-2013.

PubMed

Ketterl, Tyler G; Dundas, Nicolas J; Roncaioli, Steven A; Littman, Alyson J; Phipps, Amanda I

2018-03-06

Background Maternal overweight and obesity is one of the most common high-risk obstetric conditions associated with adverse birth outcomes. Smaller studies have suggested that pre-pregnancy body mass index (BMI) is associated with postpartum weight retention. Objective The primary objective of this study was to examine the association between pre-pregnancy BMI status and maternal weight retention. Study design We conducted a population-based retrospective cohort study using Washington State birth certificate data from 2003-2013. We included women who had two sequential births during this time period, with the second birth occurring within 18-36 months of the first singleton delivery date. BMI before a women's first pregnancy ("pre-pregnancy BMI") was categorized as normal (18.5-24.9 kg/m 2 ) and overweight/obese (25-40 kg/m 2 ). Women were classified as having returned to first pre-pregnancy BMI if their BMI before their second pregnancy was no more than 1 kg/m 2 more compared to their BMI before their first pregnancy. Analyses were stratified by gestational weight gain during the first pregnancy (below, met, exceeded recommended gestational weight gain). Results A total of 49,132 mothers were included in the study. Among women who met their recommended gestational weight gain, compared to mothers with a normal BMI, obese/overweight mothers were less likely to return to their pre-pregnancy BMI (76.5 vs 72.3%; RR Obese/Overweight  = 0.88; 95% CI: 0.85-0.92). A similar pattern was observed among women who exceeded their recommended gestational weight gain (62.6 vs 53.2%; RR Obese/Overweight  = 0.79, 95% CI: 0.78-0.80). Conclusion Pre-pregnancy BMI in the overweight/obese range is associated with a decreased likelihood of returning to pre-pregnancy BMI. Further research to support women during and after their pregnancy to promote behavior changes that prevent excessive weight gain during pregnancy and weight retention after birth is needed.

Body-mass index and risk of 22 specific cancers: a population-based cohort study of 5·24 million UK adults.

PubMed

Bhaskaran, Krishnan; Douglas, Ian; Forbes, Harriet; dos-Santos-Silva, Isabel; Leon, David A; Smeeth, Liam

2014-08-30

High body-mass index (BMI) predisposes to several site-specific cancers, but a large-scale systematic and detailed characterisation of patterns of risk across all common cancers adjusted for potential confounders has not previously been undertaken. We aimed to investigate the links between BMI and the most common site-specific cancers. With primary care data from individuals in the Clinical Practice Research Datalink with BMI data, we fitted Cox models to investigate associations between BMI and 22 of the most common cancers, adjusting for potential confounders. We fitted linear then non-linear (spline) models; investigated effect modification by sex, menopausal status, smoking, and age; and calculated population effects. 5·24 million individuals were included; 166,955 developed cancers of interest. BMI was associated with 17 of 22 cancers, but effects varied substantially by site. Each 5 kg/m(2) increase in BMI was roughly linearly associated with cancers of the uterus (hazard ratio [HR] 1·62, 99% CI 1·56-1·69; p<0·0001), gallbladder (1·31, 1·12-1·52; p<0·0001), kidney (1·25, 1·17-1·33; p<0·0001), cervix (1·10, 1·03-1·17; p=0·00035), thyroid (1·09, 1·00-1·19; p=0·0088), and leukaemia (1·09, 1·05-1·13; p≤0·0001). BMI was positively associated with liver (1·19, 1·12-1·27), colon (1·10, 1·07-1·13), ovarian (1·09, 1.04-1.14), and postmenopausal breast cancers (1·05, 1·03-1·07) overall (all p<0·0001), but these effects varied by underlying BMI or individual-level characteristics. We estimated inverse associations with prostate and premenopausal breast cancer risk, both overall (prostate 0·98, 0·95-1·00; premenopausal breast cancer 0·89, 0·86-0·92) and in never-smokers (prostate 0·96, 0·93-0·99; premenopausal breast cancer 0·89, 0·85-0·94). By contrast, for lung and oral cavity cancer, we observed no association in never smokers (lung 0·99, 0·93-1·05; oral cavity 1·07, 0·91-1·26): inverse associations overall were driven by current smokers and ex-smokers, probably because of residual confounding by smoking amount. Assuming causality, 41% of uterine and 10% or more of gallbladder, kidney, liver, and colon cancers could be attributable to excess weight. We estimated that a 1 kg/m(2) population-wide increase in BMI would result in 3790 additional annual UK patients developing one of the ten cancers positively associated with BMI. BMI is associated with cancer risk, with substantial population-level effects. The heterogeneity in the effects suggests that different mechanisms are associated with different cancer sites and different patient subgroups. National Institute for Health Research, Wellcome Trust, and Medical Research Council. Copyright © 2014 Bhaskaran et al. Open Access article distributed under the terms of CC BY. Published by Elsevier Ltd. All rights reserved.

Structure-Property Relationships of Bismaleimides

NASA Technical Reports Server (NTRS)

Tenteris-Noebe, Anita D.

1997-01-01

The purpose of this research was to control and systematically vary the network topology of bismaleimides through cure temperature and chemistry (addition of various coreactants) and subsequently attempt to determine structure-mechanical property relationships. Characterization of the bismaleimide structures by dielectric, rheological, and thermal analyses, and density measurements was subsequently correlated with mechanical properties such as modulus, yield strength, fracture energy, and stress relaxation. The model material used in this investigation was 4,4'-BismaleiMidodIphenyl methane (BMI). BMI was coreacted with either 4,4'-Methylene Dianiline (MDA), o,o'-diallyl bisphenol A (DABA) from Ciba Geigy, or Diamino Diphenyl Sulfone (DDS). Three cure paths were employed: a low- temperature cure of 140 C where chain extension should predominate, a high-temperature cure of 220 C where both chain extension and crosslinking should occur simultaneously, and a low-temperature (140 C) cure followed immediately by a high-temperature (220 C) cure where the chain extension reaction or amine addition precedes BMI homopolymerization or crosslinking. Samples of cured and postcured PMR-15 were also tested to determine the effects of postcuring on the mechanical properties. The low-temperature cure condition of BMI/MDA exhibited the highest modulus values for a given mole fraction of BMI with the modulus decreasing with decreasing concentration of BMI. The higher elastic modulus is the result of steric hindrance by unreacted BMI molecules in the glassy state. The moduli values for the high- and low/high-temperature cure conditions of BMI/MDA decreased as the amount of diamine increased. All the moduli values mimic the yield strength and density trends. For the high-temperature cure condition, the room- temperature modulus remained constant with decreasing mole fraction of BMT for the BMI/DABA and BMI/DDS systems. Postcuring PMR-15 increases the modulus over that of the cured material even though density values of cured and postcured PMR were essentially the same. Preliminary results of a continuous and intermittent stress relaxation experiment for BMI:MDA in a 2:1 molar ratio indicate that crosslinking is occurring when the sample is in the undeformed state. Computer simulation of properties such as density, glass transition temperature, and modulus for the low- temperature cure conditions of BMI/MDA and BMI/DABA were completed. The computer modeling was used to help further understand and confirm the structure characterization results. The simulations correctly predicted the trends of these properties versus mole fraction BMI and were extended to other BMI/diamine systems.

Sleep Duration and Body Mass Index in Twins: A Gene-Environment Interaction

PubMed Central

Watson, Nathaniel F.; Harden, Kathryn Paige; Buchwald, Dedra; Vitiello, Michael V.; Pack, Allan I.; Weigle, David S.; Goldberg, Jack

2012-01-01

Study Objectives: To examine whether sleep duration modifies genetic and environmental influences on body mass index (BMI). Design: Genotype-environment interaction twin study. Setting: University of Washington Twin Registry. Patients or Participants: A population-based sample of US twins (1,088 pairs, 604 monozygotic, 484 dizygotic; 66% female; mean age = 36.6 yr, standard deviation (SD) = 15.9 yr). Interventions: N/A. Measurements and Results: Participants self-reported information on height, weight, and sleep. Mean BMI was calculated as 25.3 kg/m2 (SD = 5.4) and mean habitual sleep duration was 7.2 hr/night (SD = 1.2). Data were analyzed using biometric genetic interaction models. Overall the heritability of sleep duration was 34%. Longer sleep duration was associated with decreased BMI (P < 0.05). The heritability of BMI when sleep duration was < 7 hr (h2 = 70%) was more than twice as large as the heritability of BMI when sleep duration was ≥ 9 hr (h2 = 32%); this interaction was significant (P < 0.05). Conclusions: Shorter sleep duration is associated with increased BMI and increased genetic influences on BMI, suggesting that shorter sleep duration increases expression of genetic risks for high body weight. At the same time, longer sleep duration may suppress genetic influences on body weight. Future research aiming to identify specific genotypes for BMI may benefit by considering the moderating role of sleep duration. Citation: Watson NF; Harden KP; Buchwald D; Vitiello MV; Pack AI; Weigle DS; Goldberg J. Sleep duration and body mass index in twins: a gene-environment interaction. SLEEP 2012;35(5):597-603. PMID:22547885

Twenty-five year trends in body mass index by education and income in Finland

PubMed Central

2012-01-01

Background The socioeconomic gradient in obesity and overweight is amply documented. However, the contribution of different socioeconomic indicators on trends of body mass index (BMI) over time is less well known. The aim of this study was to investigate the associations of education and income with (BMI) from the late 1970s to the early 2000s. Methods Data were derived from nationwide cross-sectional health behaviour surveys carried out among Finns annually since 1978. This study comprises data from a 25-year period (1978–2002) that included 25 339 men and 25 330 women aged 25–64 years. BMI was based on self-reported weight and height. Education in years was obtained from the questionnaire and household income from the national tax register. In order to improve the comparability of the socioeconomic position measures, education and income were divided into gender-specific tertiles separately for each study year. Linear regression analysis was applied. Results An increase in BMI was observed among men and women in all educational and income groups. In women, education and income were inversely associated with BMI. The magnitudes of the associations fluctuated but stayed statistically significant over time. Among the Finnish men, socioeconomic differences were more complicated. Educational differences were weaker than among the women and income differences varied according to educational level. At the turn of the century, the high income men in the lowest educational group had the highest BMI whereas the income pattern in the highest educational group was the opposite. Conclusion No overall change in the socio-economic differences of BMI was observed in Finland between 1978 and 2002. However, the trends of BMI diverged in sub-groups of the studied population: the most prominent increase in BMI took place in high income men with low education and in low income men with high education. The results encourage further research on the pathways between income, education, living conditions and the increasing BMI. PMID:23113905

Predictors of emotional eating during adolescents' transition to college: does body mass index moderate the association between stress and emotional eating?

PubMed

Wilson, Shana M; Darling, Katherine E; Fahrenkamp, Amy J; D'Auria, Alexandra L; Sato, Amy F

2015-01-01

This study sought to (1) examine perceived stress and resources to cope with stress as predictors of emotional eating during the transition to college and (2) determine whether body mass index (BMI) moderated the emotional eating-stress relationship. Participants were 97 college freshmen (73% female; BMI: M = 25.3 kg/m(2), SD = 5.7 kg/m(2)). Research was conducted in September 2012. Participants completed the Perceived Stress Scale, Emotional Eating Scale, and Eating and Appraisal Due to Emotions and Stress Questionnaire during the first month of college. Height and weight were measured objectively. BMI moderated the relationship between perceived stress and emotional eating. Higher stress predicted greater emotional eating for the lower BMI groups, but not the highest group. Greater resources to cope with stress predicted lower emotional eating. Greater perceived stress and poorer resources to cope with stress may contribute to emotional eating during the transition to college. The relationship between perceived stress and emotional eating may vary by BMI.

Maternal Employment, Work Schedules, and Children’s Body Mass Index

PubMed Central

Morrissey, Taryn W.; Dunifon, Rachel E.; Kalil, Ariel

2011-01-01

Previous work has shown that mothers’ employment is associated with increases in children’s body mass index (BMI), a measure of weight-for-height. Nonstandard work (working evenings/nights, weekends, or an irregular shift) may also be associated with children’s BMI. In this paper we examine the association between maternal work and children’s BMI, and also consider the influence of mothers’ nonstandard work schedules. Using data from school-age children in the NICHD’s Study of Early Child Care and Youth Development (N = 990), we found that an increase in the total time a mother is employed is associated with an increase in her child’s BMI; additionally, we find that the association between maternal employment and children’s weight is much stronger at 6th grade relative to younger ages. There was no evidence that maternal or home characteristics or children’s time use mediated these associations, nor was there any evidence that nonstandard work was associated with children’s BMI. Implications for policy and future research are discussed. PMID:21291429

High hunger state increases olfactory sensitivity to neutral but not food odors.

PubMed

Stafford, Lorenzo D; Welbeck, Kimberley

2011-01-01

Understanding how hunger state relates to olfactory sensitivity has become more urgent due to their possible role in obesity. In 2 studies (within-subjects: n = 24, between-subjects: n = 40), participants were provided with lunch before (satiated state) or after (nonsatiated state) testing and completed a standardized olfactory threshold test to a neutral odor (Experiments 1 and 2) and discrimination test to a food odor (Experiment 2). Experiment 1 revealed that olfactory sensitivity was greater in the nonsatiated versus satiated state, with additionally increased sensitivity for the low body mass index (BMI) compared with high BMI group. Experiment 2 replicated this effect for neutral odors, but in the case of food odors, those in a satiated state had greater acuity. Additionally, whereas the high BMI group had higher acuity to food odors in the satiated versus nonsatiated state, no such differences were found for the low BMI group. The research here is the first to demonstrate how olfactory acuity changes as a function of hunger state and relatedness of odor to food and that BMI can predict differences in olfactory sensitivity.

School gardens and adolescent nutrition and BMI: Results from a national, multilevel study.

PubMed

Utter, Jennifer; Denny, Simon; Dyson, Ben

2016-02-01

The aim of the current study was to determine the impact of school gardens on student eating behaviors, physical activity and BMI in New Zealand secondary schools. The current study also aimed to determine if school gardens could buffer the association between household poverty and adolescent BMI. Data were drawn from a national study of the health and wellbeing of New Zealand secondary school students (n=8500) conducted in 2012. Multilevel regression models were used to determine the association between school gardens (school-level) and student nutrition behaviors, physical activity and measured BMI (student-level). Approximately half of secondary schools had a fruit/vegetable garden for students to participate in. School gardens were associated with lower student BMI (p=0.01) and lower prevalence of overweight (p<0.01). School gardens appear to have a positive impact on student health. Future research may explore how school gardens are implemented to better understand their impact and to extend the benefits beyond the school community. Copyright © 2015 Elsevier Inc. All rights reserved.

Body mass index, body esteem, and unprotected receptive anal intercourse among young men who have sex with men who seek partners online.

PubMed

Meanley, Steven; Hickok, Andrew; Johns, Michelle Marie; Pingel, Emily S; Bauermeister, José A

2014-05-01

Research examining the relationship between body mass index (BMI) and sexual risk outcomes among men who have sex with men (MSM) has yielded inconsistent results. Using a web-based survey, single-identified (e.g., not in a relationship) young MSM (N = 431) between the ages of 18 and 24 years who sought romantic partners online were asked to respond to items regarding their BMI, body image (e.g., attribution, dissatisfaction, and pride), and sexual risk behaviors. We used Poisson regressions to examine the relationships between BMI, body image, and the number of unprotected receptive anal intercourse (URAI) occasions and partners in the past 2 months. We found a curvilinear relationship between BMI and URAI occasions, and a linear relationship between BMI and URAI partners. These relationships persisted after accounting for body image. Further, we found that body attribution served as a protective factor whereas body pride served as a risk factor. We discuss the implications of our findings for sexual health education and HIV prevention.

Longitudinal associations between family characteristics and measures of childhood obesity.

PubMed

Lehto, Reetta; Ray, Carola; Roos, Eva

2012-06-01

The objective of this study was to investigate cross-sectional and longitudinal associations between different family characteristics and body mass index (BMI) and waist-to-height ratio (WHtR) in children. This was a prospective follow-up study conducted in Helsinki region with data collected in 2006 and 2008. The sample consisted of 550 children aged 9-11 at baseline. Children were measured and weighed by research staff, and they completed a questionnaire about their family characteristics. More meals together with the family, more parenting practices at meals, less time home without adult company after school, and child's perception of receiving care from mother in 2006 predicted a lower BMI in 2008 and partly a smaller increase in BMI from 2006 to 2008. Fewer associations were found to WHtR. Physical activity with either parent was not associated with BMI or WHtR. Several family characteristics predicted child BMI and WHtR 2 years later. These results contribute new knowledge about parental influence on child weight and weight gain and should be taken into account when planning interventions on the matter.

Genetically Predicted Body Mass Index and Alzheimer’s Disease Related Phenotypes in Three Large Samples: Mendelian Randomization Analyses

PubMed Central

Mukherjee, Shubhabrata; Walter, Stefan; Kauwe, John S.K.; Saykin, Andrew J.; Bennett, David A.; Larson, Eric B.; Crane, Paul K.; Glymour, M. Maria

2015-01-01

Observational research shows that higher body mass index (BMI) increases Alzheimer’s disease (AD) risk, but it is unclear whether this association is causal. We applied genetic variants that predict BMI in Mendelian Randomization analyses, an approach that is not biased by reverse causation or confounding, to evaluate whether higher BMI increases AD risk. We evaluated individual level data from the AD Genetics Consortium (ADGC: 10,079 AD cases and 9,613 controls), the Health and Retirement Study (HRS: 8,403 participants with algorithm-predicted dementia status) and published associations from the Genetic and Environmental Risk for AD consortium (GERAD1: 3,177 AD cases and 7,277 controls). No evidence from individual SNPs or polygenic scores indicated BMI increased AD risk. Mendelian Randomization effect estimates per BMI point (95% confidence intervals) were: ADGC OR=0.95 (0.90, 1.01); HRS OR=1.00 (0.75, 1.32); GERAD1 OR=0.96 (0.87, 1.07). One subscore (cellular processes not otherwise specified) unexpectedly predicted lower AD risk. PMID:26079416

Evaluating obesity in fibromyalgia: neuroendocrine biomarkers, symptoms, and functions.

PubMed

Okifuji, Akiko; Bradshaw, David H; Olson, Chrisana

2009-04-01

The aim of this study was to investigate the associations between obesity and fibromyalgia syndrome (FMS). This study was conducted at the University of Utah Pain Management and Research Center, Salt Lake City, Utah. Thirty-eight FMS patients were included in this study. Neuroendocrine indices (catecholamines, cortisol, C-reactive protein [CRP], and interleukin-6), symptom measures (Fibromyalgia Impact Questionnaire), sleep indices (Actigraph), and physical functioning (treadmill testing) were measured. Body mass index (BMI) provided the primary indicator of obesity. Approximately 50% of the patients were obese and an additional 21% were overweight. Strong positive associations were found between BMI and levels of IL-6 (r=0.52) and epinephrine (r=0.54), and somewhat weaker associations with cortisol (r=0.32) and CRP (r=0.37). BMI was also related to maximal heart rate (r=0.33) and inversely related to distance walked (r= -0.41). BMI was associated with disturbed sleep: total sleep time (r= -0.56) and sleep efficiency (r= -0.44). No associations between self-reported symptoms and BMI were found. This study provides preliminary evidence suggesting that obesity plays a role in FMS-related dysfunction.

Is Childhood Socioeconomic Status Independently Associated with Adult BMI after Accounting for Adult and Neighborhood Socioeconomic Status?

PubMed Central

2017-01-01

Childhood socioeconomic status (SES) is inversely associated with adult weight in high income countries. Whether the influence of childhood SES on adult weight is best described using a critical period model or an accumulation of risk model is not yet settled. This research tests whether childhood SES is associated with adult BMI and likelihood of obesity independent of adult socioeconomic status and neighborhood characteristics. Data on individual childhood and adult characteristics come from the Health and Retirement Study (N = 13,545). Data on neighborhood characteristics come from the 2000 Decennial Census and American Community Survey (2005–2009). In the fully adjusted models, perceived financial hardship before the age of sixteen and having a father who was unemployed are associated with higher BMI among males and, among females, paternal education remains associated with adult BMI. However, childhood SES is not associated with likelihood of obesity after fully adjusting for adult SES and neighborhood characteristics, suggesting that the direct effects of early childhood SES on BMI are small relative to the other factors associated with obesity in adulthood. PMID:28095430

Relationship between body mass index and renal function deterioration among the Taiwanese chronic kidney disease population.

PubMed

Chang, Tian-Jong; Zheng, Cai-Mei; Wu, Mei-Yi; Chen, Tzu-Ting; Wu, Yun-Chun; Wu, Yi-Lien; Lin, Hsin-Ting; Zheng, Jing-Quan; Chu, Nain-Feng; Lin, Yu-Me; Su, Sui-Lung; Lu, Kuo-Cheng; Chen, Jin-Shuen; Sung, Fung-Chang; Lee, Chien-Te; Yang, Yu; Hwang, Shang-Jyh; Wang, Ming-Cheng; Hsu, Yung-Ho; Chiou, Hung-Yi; Kao, Senyeong; Lin, Yuh-Feng

2018-05-02

This study investigated the characteristics of patients with different chronic kidney disease (CKD) stages according to various body mass index (BMI) categories and determined the influence of BMI in renal function deterioration. We conducted a multicenter, longitudinal cohort study based on the Epidemiology and Risk Factors Surveillance of CKD project (2008-2013) and National Health Insurance Research Database (2001-2013). A total of 7357 patients with CKD aged 20-85 years from 14 hospitals were included in the study. A higher male sex, diabetes mellitus (DM) and hypertension were noted among overweight and obese CKD patients, while more cancer prevalence was noted among underweight CKD patients. Charlson comorbidity index was significantly higher and correlated with BMI among late CKD patients. Patients with BMI < 18.5 kg/m 2 exhibited non-significantly higher events of eGFR decline events in both early and late CKD stages than other BMI groups. BMI alone is not a determinant of CKD progression among our Taiwanese CKD patients. Obesity should be re-defined and body weight manipulation should be individualized in CKD patients.

The Heterogeneity of the Cigarette Price Effect on Body Mass Index

PubMed Central

Courtemanche, Charles J.

2012-01-01

Previous studies estimate the average effect of cigarette price on body mass index (BMI), with recent research showing that their different methodologies all point to a negative effect after several years. This literature, however, ignores the possibility that the effect could vary throughout the BMI distribution or across socioeconomic and demographic groups due to differences in underlying obesity risks or preferences for health. We evaluate heterogeneity in the long-run impact of cigarette price on BMI by performing quantile regressions and stratifying the sample by race, education, age, and sex. Cigarette price has a highly heterogeneous negative effect that is more than three times as strong at high BMI levels – where weight loss is most beneficial for health – than at low levels. The effects are also strongest for blacks, college graduates, middle-aged adults, and women. We also assess the implications for disparities, conduct robustness checks, and evaluate potential mechanisms. PMID:22842751

Prefrontal gray matter volume mediates genetic risks for obesity.

PubMed

Opel, N; Redlich, R; Kaehler, C; Grotegerd, D; Dohm, K; Heindel, W; Kugel, H; Thalamuthu, A; Koutsouleris, N; Arolt, V; Teuber, A; Wersching, H; Baune, B T; Berger, K; Dannlowski, U

2017-05-01

Genetic and neuroimaging research has identified neurobiological correlates of obesity. However, evidence for an integrated model of genetic risk and brain structural alterations in the pathophysiology of obesity is still absent. Here we investigated the relationship between polygenic risk for obesity, gray matter structure and body mass index (BMI) by the use of univariate and multivariate analyses in two large, independent cohorts (n=330 and n=347). Higher BMI and higher polygenic risk for obesity were significantly associated with medial prefrontal gray matter decrease, and prefrontal gray matter was further shown to significantly mediate the effect of polygenic risk for obesity on BMI in both samples. Building on this, the successful individualized prediction of BMI by means of multivariate pattern classification algorithms trained on whole-brain imaging data and external validations in the second cohort points to potential clinical applications of this imaging trait marker.

People, organizational, and leadership factors impacting informatics support for clinical and translational research

PubMed Central

2013-01-01

Background In recent years, there have been numerous initiatives undertaken to describe critical information needs related to the collection, management, analysis, and dissemination of data in support of biomedical research (J Investig Med 54:327-333, 2006); (J Am Med Inform Assoc 16:316–327, 2009); (Physiol Genomics 39:131-140, 2009); (J Am Med Inform Assoc 18:354–357, 2011). A common theme spanning such reports has been the importance of understanding and optimizing people, organizational, and leadership factors in order to achieve the promise of efficient and timely research (J Am Med Inform Assoc 15:283–289, 2008). With the emergence of clinical and translational science (CTS) as a national priority in the United States, and the corresponding growth in the scale and scope of CTS research programs, the acuity of such information needs continues to increase (JAMA 289:1278–1287, 2003); (N Engl J Med 353:1621–1623, 2005); (Sci Transl Med 3:90, 2011). At the same time, systematic evaluations of optimal people, organizational, and leadership factors that influence the provision of data, information, and knowledge management technologies and methods are notably lacking. Methods In response to the preceding gap in knowledge, we have conducted both: 1) a structured survey of domain experts at Academic Health Centers (AHCs); and 2) a subsequent thematic analysis of public-domain documentation provided by those same organizations. The results of these approaches were then used to identify critical factors that may influence access to informatics expertise and resources relevant to the CTS domain. Results A total of 31 domain experts, spanning the Biomedical Informatics (BMI), Computer Science (CS), Information Science (IS), and Information Technology (IT) disciplines participated in a structured surveyprocess. At a high level, respondents identified notable differences in theaccess to BMI, CS, and IT expertise and services depending on the establishment of a formal BMI academic unit and the perceived relationship between BMI, CS, IS, and IT leaders. Subsequent thematic analysis of the aforementioned public domain documents demonstrated a discordance between perceived and reported integration across and between BMI, CS, IS, and IT programs and leaders with relevance to the CTS domain. Conclusion Differences in people, organization, and leadership factors do influence the effectiveness of CTS programs, particularly with regard to the ability to access and leverage BMI, CS, IS, and IT expertise and resources. Based on this finding, we believe that the development of a better understanding of how optimal BMI, CS, IS, and IT organizational structures and leadership models are designed and implemented is critical to both the advancement of CTS and ultimately, to improvements in the quality, safety, and effectiveness of healthcare. PMID:23388243

Impact of Masked Replacement of Sugar-Sweetened with Sugar-Free Beverages on Body Weight Increases with Initial BMI: Secondary Analysis of Data from an 18 Month Double–Blind Trial in Children

PubMed Central

Katan, Martijn B.; de Ruyter, Janne C.; Kuijper, Lothar D. J.; Chow, Carson C.; Hall, Kevin D.; Olthof, Margreet R.

2016-01-01

Background Substituting sugar-free for sugar-sweetened beverages reduces weight gain. This effect may be more pronounced in children with a high body mass index (BMI) because their sensing of kilocalories might be compromised. We investigated the impact of sugar-free versus sugary drinks separately in children with a higher and a lower initial BMI z score, and predicted caloric intakes and degree of compensation in the two groups. Methods and Findings This is a secondary, explorative analysis of our double-blind randomized controlled trial (RCT) which showed that replacement of one 250-mL sugary drink per day by a sugar—free drink for 18 months significantly reduced weight gain. In the 477 children who completed the trial, mean initial weights were close to the Dutch average. Only 16% were overweight and 3% obese. Weight changes were expressed as BMI z-score, i.e. as standard deviations of the BMI distribution per age and sex group. We designated the 239 children with an initial BMI z-score below the median as ‘lower BMI’ and the 238 children above the median as ‘higher BMI’. The difference in caloric intake from experimental beverages between treatments was 86 kcal/day both in the lower and in the higher BMI group. We used a multiple linear regression and the coefficient of the interaction term (initial BMI group times treatment), indicated whether children with a lower BMI responded differently from children with a higher BMI. Statistical significance was defined as p ≤ 0.05. Relative to the sugar sweetened beverage, consumption of the sugar—free beverage for 18 months reduced the BMI z-score by 0.05 SD units within the lower BMI group and by 0.21 SD within the higher BMI group. Body weight gain was reduced by 0.62 kg in the lower BMI group and by 1.53 kg in the higher BMI group. Thus the treatment reduced the BMI z-score by 0.16 SD units more in the higher BMI group than in the lower BMI group (p = 0.04; 95% CI -0.31 to -0.01). The impact of the intervention on body weight gain differed by 0.90 kg between BMI groups (p = 0.09; 95% CI -1.95 to 0.14). In addition, we used a physiologically-based model of growth and energy balance to estimate the degree to which children had compensated for the covertly removed sugar kilocalories by increasing their intake of other foods. The model predicts that children with a lower BMI had compensated 65% (95% CI 28 to 102) of the covertly removed sugar kilocalories, whereas children with a higher BMI compensated only 13% (95% CI -37 to 63). Conclusions The children with a BMI above the median might have a reduced tendency to compensate for changes in caloric intake. Differences in these subconscious compensatory mechanisms may be an important cause of differences in the tendency to gain weight. If further research bears this out, cutting down on the intake of sugar-sweetened drinks may benefit a large proportion of children, especially those who show a tendency to become overweight. Trial Registration ClinicalTrials.gov NCT00893529 PMID:27447721

Body-mass index, blood pressure, and cause-specific mortality in India: a prospective cohort study of 500 810 adults.

PubMed

Gajalakshmi, Vendhan; Lacey, Ben; Kanimozhi, Vendhan; Sherliker, Paul; Peto, Richard; Lewington, Sarah

2018-07-01

The association between cause-specific mortality and body-mass index (BMI) has been studied mainly in high-income countries. We investigated the relations between BMI, systolic blood pressure, and mortality in India. Men and women aged 35 years or older were recruited into a prospective study from the general population in Chennai, India between Jan 1, 1998, and Dec 31, 2001. Participants were interviewed (data collected included age, sex, education, socioeconomic status, medical history, tobacco smoking, and alcohol intake) and measured (height, weight, and blood pressure). Deaths were identified by linkage to Chennai city mortality records and through active surveillance by household visits from trained graduate non-medical fieldworkers. After the baseline survey, households were visited once in 2002-05, then biennially until 2015. During these repeat visits, structured narratives of any deaths that took place before March 31, 2015, were recorded for physician coding. During 2013-14, a random sample of participants was also resurveyed as per baseline to assess long-term variability in systolic blood pressure and BMI. Cox regression (standardised for tobacco, alcohol, and social factors) was used to relate mortality rate ratios (RRs) at ages 35-69 years to systolic blood pressure, BMI, or BMI adjusted for usual systolic blood pressure. 500 810 participants were recruited. After exclusion of those with chronic disease or incomplete data, 414 746 participants aged 35-69 years (mean 46 [SD 9]; 45% women) remained. At recruitment, mean systolic blood pressure was 127 mm Hg (SD 15), and mean BMI was 23·2 kg/m 2 (SD 3·8). Correlations of resurvey and baseline measurements were 0·50 for systolic blood pressure and 0·88 for BMI. Low BMI was strongly associated with poverty, tobacco, and alcohol. Of the 29 519 deaths at ages 35-69 years, the cause was vascular for 14 935 deaths (12 504 cardiac, 1881 stroke, and 550 other). Vascular mortality was strongly associated with systolic blood pressure: RRs per 20 mm Hg increase in usual systolic blood pressure were 2·45 (95% CI 2·16-2·78) for stroke mortality, 1·74 (1·64-1·84) for cardiac mortality, and 1·84 (1·75-1·94) for all vascular mortality. Although BMI strongly affected systolic blood pressure (an increase of about 1 mm Hg per kg/m 2 ) and diabetes prevalence, BMI was little related to cardiac or stroke mortality, with only small excesses even for grade 1 obesity (ie, BMIs of 30·0-35·0 kg/m 2 ). After additional adjustment for usual systolic blood pressure, BMI was inversely related to cardiac and stroke mortality throughout the range 15·0-30·0 kg/m 2 : when underweight participants (ie, BMI 15·0-18·5 kg/m 2 ) were compared with overweight participants (ie, BMI 25·0-30·0 kg/m 2 ), the blood-pressure-adjusted RR was 1·28 (95% CI 1·20-1·38) for cardiac mortality and 1·46 (1·22-1·73) for stroke mortality. In this South Asian population, BMI was little associated with vascular mortality, even though increased BMI is associated with increased systolic blood pressure, which in turn is associated with increased vascular mortality. Hence, some close correlates of below-average BMI must have important adverse effects, which could be of relevance in all populations. UK Medical Research Council, British Heart Foundation, Cancer Research UK. Copyright © 2018 The Author(s). Published by Elsevier Ltd.This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.

The Impact of Telephonic Wellness Coaching on Weight Loss: A “Natural Experiments for Translation in Diabetes (NEXT-D)” Study

PubMed Central

Schmittdiel, Julie A.; Adams, Sara R.; Goler, Nancy; Sanna, Rashel S.; Boccio, Mindy; Bellamy, David J.; Brown, Susan D.; Neugebauer, Romain S.; Ferrara, Assiamira

2016-01-01

Objective To evaluate the impact of a population-based telephonic wellness coaching program on weight loss. Methods Individual-level segmented regression analysis of interrupted time series data comparing the BMI trajectories in the 12 months before vs. the 12 months after initiating coaching among a cohort of Kaiser Permanente Northern California (KPNC) members (n=954) participating in The Permanente Medical Group (TPMG) Wellness Coaching program in 2011. The control group was a 20:1 propensity-score matched control group (n=19,080) matched with coaching participants based on baseline demographic and clinical characteristics. Results Wellness coaching participants had a significant upward trend in BMI in the 12 months before their first Wellness coaching session, and a significant downward trend in BMI in the 12 months after their first session equivalent to a clinically significant reduction of greater than one unit of baseline BMI (p<.01 for both). The control group did not have statistically significant decreases in BMI during the post-period. Conclusions Wellness coaching has a positive impact on BMI reduction that is both statistically and clinically significant. Future research and quality improvement efforts should focus on disseminating Wellness coaching for weight loss in diabetes patients and those at risk for developing the disease. PMID:28124501

US States' Childhood Obesity Surveillance Practices and Recommendations for Improving Them, 2014-2015.

PubMed

Blondin, Kelly J; Giles, Catherine M; Cradock, Angie L; Gortmaker, Steven L; Long, Michael W

2016-07-28

Routine collection, analysis, and reporting of data on child height, weight, and body mass index (BMI), particularly at the state and local levels, are needed to monitor the childhood obesity epidemic, plan intervention strategies, and evaluate the impact of interventions. Child BMI surveillance systems operated by the US government do not provide state or local data on children across a range of ages. The objective of this study was to describe the extent to which state governments conduct child BMI surveillance. From August through December 2014, we conducted a structured telephone survey with state government administrators to learn about state surveillance of child BMI. We also searched websites of state health and education agencies for information about state surveillance. State agency administrators in 48 states and Washington, DC, completed telephone interviews (96% response rate). Based on our interviews and Internet research, we determined that 14 states collect child BMI data in a manner consistent with standard definitions of public health surveillance. The absence of child BMI surveillance systems in most states limits the ability of public health practitioners and policymakers to develop and evaluate responses to the childhood obesity epidemic. Greater investment in surveillance is needed to identify the most effective and cost-effective childhood obesity interventions.

Pre-pregnancy body mass index and gestational weight gain and their effects on pregnancy and birth outcomes: a cohort study in West Sumatra, Indonesia.

PubMed

Soltani, Hora; Lipoeto, Nur I; Fair, Frankie J; Kilner, Karen; Yusrawati, Y

2017-11-09

Indonesia has a considerably high incidence of maternal and infant mortality. The country has however been experiencing a social and economic transition, influencing its general population demographics and nutritional status including the state of health and nutrition of pregnant women. This study aimed to explore body mass index (BMI) and gestational weight gain (GWG), and their relationship with pregnancy outcomes in a sample of Indonesian pregnant women. This observational cohort study included a total of 607 pregnant women who were recruited in 2010 from maternity clinics in Western Sumatra, Indonesia. Multiple logistic and regression analyses were undertaken to compare pregnancy and birth outcomes for different BMI and GWG, using normal weight women and women with a recommended weight gain as the referent groups. The prevalence of underweight (BMI < 18.5 kg/m 2 ) in pregnancy was high at 20.1%; while 21.7% of women were overweight (BMI: 23.0-27.4 kg/m 2 ) and 5.3% obese (BMI ≥ 27.5 kg/m 2 ) using the Asian BMI classifications. The incidence of overweight (BMI: 25.0-29.9 kg/m 2 ) and obese (BMI ≥ 30.0 kg/m 2 ) according to the international BMI classifications were 13.5% and 1.1% respectively. The majority of women gained inadequate weight in pregnancy compared to the Institute of Medicine (IOM) recommendations, especially those who had a normal BMI. Birthweight adjusted mean difference aMD (95% confidence interval) 205 (46,365) and the odds of macrosomia adjusted odds ratio aOR 13.46 (2.32-77.99) significantly increased in obese women compared to those with a normal BMI. Birthweight aMD -139 (-215, -64) significantly decreased in women with inadequate GWG compared to those with recommended GWG, while SGA aOR 5.44 (1.36, 21.77) and prematurity aOR 3.55 (1.23, 10.21) increased. Low nutritional status and inadequate GWG remain a cause for concern in these women. The higher odds of macrosomia with increasing maternal BMI and higher odds of prematurity and small for gestational age infants with inadequate weight gain also require attention. Research and practice recommendations: Urgent attention is required by researchers, policy makers and decision-makers to facilitate development of culturally sensitive interventions to enhance nutritional status and health of mothers and babies, in an area known for its high incidence of maternal and neonatal mortality.

Longitudinal associations between key dietary behaviors and weight gain over time: Transitions through the adolescent years

PubMed Central

Laska, Melissa N.; Murray, David M.; Lytle, Leslie A.; Harnack, Lisa J.

2012-01-01

Previous studies have yielded inconsistent results in documenting the association between key dietary factors and adolescent weight change over time. The purpose of this study was to examine the extent to which changes in adolescent sugar-sweetened beverage, diet soda, breakfast and fast food consumption were associated with changes in BMI and percent body fat (PBF), both cross-sectionally and longitudinally. Our sample included 693 Minnesota adolescents followed over two years. Adjusting for physical activity, puberty, race, socio-economic status, age, and total energy intake, cross-sectional findings indicated that for both males and females, diet soda consumption was significantly and positively associated with BMI and PBF, and breakfast intake was significantly and negatively associated with BMI and PBF among girls. In longitudinal analyses, however, there were no significant associations after adjusting for the number of tests performed. This study adds to previous research through its methodological strengths, including adjustment for physical activity and energy intake assessed using state-of-the-art methods (i.e., accelerometers and 24-hour dietary recalls), as well as its evaluation of both BMI and PBF. Additional research is needed to better understand the complex constellation of factors that contribute to adolescent weight gain over time. PMID:21701567

Weight change between successive pregnancies and risks of stillbirth and infant mortality: a nationwide cohort study.

PubMed

Cnattingius, Sven; Villamor, Eduardo

2016-02-06

Maternal overweight and obesity are risk factors for stillbirth and infant mortality. Whether temporal changes in maternal weight affect these risks is not clear. We aimed to assess whether change of BMI between first and second pregnancies affects risks of stillbirth and infant mortality in the second-born offspring. In a Swedish population-based cohort of women who gave birth to their first and second child between Jan 1, 1992, and Dec 31, 2012, we investigated associations between change in maternal body-mass index (BMI) during early pregnancy from first to second pregnancies and risks of stillbirth and neonatal, postneonatal, and infant mortality after the second pregnancy. Relative risks (RRs) for each outcome according to BMI change categories were calculated with binomial regression. Complete information was available for 456,711 (77.7%) of 587,710 women who had their first and second single births in the study period. Compared with women with a stable BMI (change between -1 kg/m(2) and <1 kg/m(2)) between pregnancies, the adjusted RRs for women who gained at least 4 BMI units between pregnancies were 1.55 (95% CI 1.23-1.96) for stillbirth and 1.29 (1.00-1.67) for infant mortality. Stillbirth risks increased linearly with increased BMI gain. Risks of infant mortality in second pregnancy only increased with BMI gain in women with healthy BMI (<25 kg/m(2)) during first pregnancy; the adjusted RR for healthy weight women who gained 2 to less than 4 BMI units was 1.27 (1.01-1.59) and for those who gained 4 BMI units or more the adjusted RR was 1.60 (1.16-2.22). In overweight women (BMI ≥25 kg/m(2)), weight loss before pregnancy reduced risk of neonatal mortality. Our findings emphasise the need to prevent weight gain before pregnancy in healthy and overweight women and that weight loss should be promoted in overweight women. Swedish Research Council for Health, Working Life and Welfare, and Karolinska Institutet. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of a Biomedical Informatics course for medical students: a pre-posttest study at UNAM Faculty of Medicine in Mexico.

PubMed

Sánchez-Mendiola, Melchor; Martínez-Franco, Adrián I; Lobato-Valverde, Marlette; Fernández-Saldívar, Fabián; Vives-Varela, Tania; Martínez-González, Adrián

2015-04-01

Biomedical Informatics (BMI) education in medical schools is developing a sound curricular base, but there are few published reports of their educational usefulness. The goal of this paper is to assess knowledge change and satisfaction in medical students after a BMI curriculum. The National Autonomous University of México Faculty of Medicine (UNAM) recently implemented a curricular reform that includes two BMI sequential courses (BMI-1 and BMI-2). The research design was one-group pretest-posttest. An objective test with evidence of validity was used for knowledge measurement. A satisfaction questionnaire was applied at the end of the courses. Two-tailed paired Student's t-tests were applied, comparing knowledge scores in the pre and post-test for each course. The study included student cohorts during two consecutive academic years. The 2013 BMI-1 course (n = 986 students) knowledge pretest score was 43.0 ± 8.6 (mean percent correct ± SD), and the post-test score was 57.7 ± 10.3 (p < 0.001); the 2014 BMI-1 (n = 907) pretest score was 43.7 ± 8.5, and the post-test was 58.1 ± 10.5 (p < 0.001). The 2012 BMI-2 course (n = 683) pretest score was 26.3 ± 7.9, the post-test score was 44.3 ± 13.3 (p < 0.001); the 2013 BMI-2 (n = 926) pretest score was 27.5 ± 7.5, and the post-test was 42.0 ± 11.0 (p < 0.001). The overall opinion of the students regarding the course was from good to excellent, with a response rate higher than 90%. The satisfaction questionnaires had high reliability (Cronbach's alpha of 0.93). The study shows a significant increase in BMI knowledge after an educational intervention in four medical student cohorts, and an overall positive evaluation by the students. Long-term follow-up is needed, as well as controlled studies of BMI educational interventions using performance endpoints.

Neighborhood food outlets, diet, and obesity among California adults, 2007 and 2009.

PubMed

Hattori, Aiko; An, Ruopeng; Sturm, Roland

2013-01-01

Varying neighborhood definitions may affect research on the association between food environments and diet and weight status. The objective of this study was to examine the association between number and type of neighborhood food outlets and dietary intake and body mass index (BMI) measures among California adults according to the geographic size of a neighborhood or food environment. We analyzed data from 97,678 respondents aged 18 years or older from the 2007 and 2009 California Health Interview Survey through multivariable regression models. Outcome variables were BMI, weight status of a BMI of 25.0 or more and a BMI of 30.0 or more, and the number of times per week the following were consumed: fruits, vegetables, sugar-sweetened soft drinks, fried potatoes, and fast food. Explanatory variables were the number of fast-food restaurants, full-service restaurants, convenience stores, small food stores, grocery stores, and large supermarkets within varying distances (0.25 to 3.0 miles) from the survey respondent's residence. We adopted as a measure of walking distance a Euclidean distance within 1 mile. Control variables included sociodemographic and economic characteristics of respondents and neighborhoods. Food outlets within walking distance (≤ 1.0 mile) were not strongly associated with dietary intake, BMI, or probabilities of a BMI of 25.0 or more or a BMI of 30.0 or more. We found significant associations between fast-food outlets and dietary intake and between supermarkets and BMI and probabilities of a BMI of 25.0 or more and a BMI of 30.0 or more for food environments beyond walking distance (> 1.0 mile). We found no strong evidence that food outlets near homes are associated with dietary intake or BMI. We replicated some associations reported previously but only for areas that are larger than what typically is considered a neighborhood. A likely reason for the null finding is that shopping patterns are weakly related, if at all, to neighborhoods in the United States because of access to motorized transportation.

Relationship between body mass index and fracture risk is mediated by bone mineral density.

PubMed

Chan, Mei Y; Frost, Steve A; Center, Jacqueline R; Eisman, John A; Nguyen, Tuan V

2014-11-01

The relationship between body mass index (BMI) and fracture risk is controversial. We sought to investigate the effect of collinearity between BMI and bone mineral density (BMD) on fracture risk, and to estimate the direct and indirect effect of BMI on fracture with BMD being the mediator. The study involved 2199 women and 1351 men aged 60 years or older. BMI was derived from baseline weight and height. Femoral neck BMD was measured by dual-energy X-ray absorptiometry (DXA; GE-LUNAR, Madison, WI, USA). The incidence of fragility fracture was ascertained by X-ray reports from 1991 through 2012. Causal mediation analysis was used to assess the mediated effect of BMD on the BMI-fracture relationship. Overall, 774 women (35% of total women) and 258 men (19%) had sustained a fracture. Approximately 21% of women and 20% of men were considered obese (BMI ≥ 30). In univariate analysis, greater BMI was associated with reduced fracture risk in women (hazard ratio [HR] 0.92; 95% confidence interval [CI], 0.85 to 0.99) and in men (HR 0.77; 95% CI, 0.67 to 0.88). After adjusting for femoral neck BMD, higher BMI was associated with greater risk of fracture in women (HR 1.21; 95% CI, 1.11 to 1.31) but not in men (HR 0.96; 95% CI, 0.83 to 1.11). Collinearity had minimal impact on the BMD-adjusted results (variance inflation factor [VIF] = 1.2 for men and women). However, in mediation analysis, it was found that the majority of BMI effect on fracture risk was mediated by femoral neck BMD. The overall mediated effect estimates were -0.048 (95% CI, -0.059 to -0.036; p < 0.001) in women and -0.030 (95% CI, -0.042 to -0.018; p < 0.001) in men. These analyses suggest that there is no significant direct effect of BMI on fracture, and that the observed association between BMI and fracture risk is mediated by femoral neck BMD in both men and women. © 2014 American Society for Bone and Mineral Research.

Body-mass index and risk of advanced chronic kidney disease: Prospective analyses from a primary care cohort of 1.4 million adults in England

PubMed Central

Bankhead, Clare; Matsushita, Kunihiro; Stevens, Sarah; Holt, Tim; Hobbs, F. D. Richard; Coresh, Josef; Woodward, Mark

2017-01-01

Background It is uncertain whether being overweight, but not obese, is associated with advanced chronic kidney disease (CKD) and how the size and shape of associations between body-mass index (BMI) and advanced CKD differs among different types of people. Methods We used Clinical Practice Research Datalink records (2000–2014) with linkage to English secondary care and mortality data to identify a prospective cohort with at least one BMI measure. Cox models adjusted for age, sex, smoking and social deprivation and subgroup analyses by diabetes, hypertension and prior cardiovascular disease assessed relationships between BMI and CKD stages 4–5 and end-stage renal disease (ESRD). Findings 1,405,016 adults aged 20–79 with mean BMI 27.4kg/m2 (SD 5.6) were followed for 7.5 years. Compared to a BMI of 20 to <25kg/m2, higher BMI was associated with a progressively increased risk of CKD stages 4–5 (hazard ratio 1.34, 95% CI 1.30–1.38 for BMI 25 to <30kg/m2; 1.94, 1.87–2.01 for BMI 30 to <35kg/m2; and 3.10, 2.95–3.25 for BMI ≥35kg/m2). The association between BMI and ESRD was shallower and reversed at low BMI. Current smoking, prior diabetes, hypertension or cardiovascular disease all increased risk of CKD, but the relative strength and shape of BMI-CKD associations, which were generally log-linear above a BMI of 25kg/m2, were similar among those with and without these risk factors. There was direct evidence that being overweight was associated with increased risk of CKD stages 4–5 in these subgroups. Assuming causality, since 2000 an estimated 39% (36–42%) of advanced CKD in women and 26% (22–30%) in men aged 40–79 resulted from being overweight or obese. Conclusions This study provides direct evidence that being overweight increases risk of advanced CKD, that being obese substantially increases such risk, and that this remains true for those with and without diabetes, hypertension or cardiovascular disease. Strategies to reduce weight among those who are overweight, as well as those who are obese may reduce CKD risk, with each unit reduction in BMI yielding similar relative reductions in risk. PMID:28273171

The correlation between body mass index, limb circumferences and blood pressure cuff fit in bariatric surgical patients.

PubMed

Schumann, R; Alyamani, O; Viswanath, A; Bonney, I

2016-01-01

The purpose of this study was to determine the correlation between body mass index (BMI) and upper and lower arm as well as lower leg circumferences and the frequency of correct blood pressure (BP) cuff fit. We explored recommendations for the most likely BP cuff size and location for the three BMI categories. Following IRB approval we retrospectively analyzed a research database of bariatric surgical patients with a BMI of ≥40 kg/m(2). Data included patients' characteristics, upper and lower arm as well as lower leg circumferences. Patients were divided into three groups based on BMI (kg/m(2), Group I: <45, Group II: 45-55, and Group III: >55). Appropriate cuff fit using a standard or large adult BP cuff (CRITIKON(®), GE Healthcare, Waukesha, Wisconsin, USA) on the upper and lower arm, and lower leg was determined. We analyzed the percent proportion of proper cuff fit for cuff sizes and locations between groups using appropriate nonparametric testing. Limb circumference correlated significantly with BMI (P = 0.01), and the upper arm correlated most closely (r = 0.76). A standard adult BP cuff on the lower arm fit properly in >90% and >80% and in Groups I and II, respectively. A large cuff on the lower arm was appropriate in 87% of Group III. In two participants, a large cuff fit properly on the lower leg. Limb circumference significantly correlated with BMI. Recommendations for proper cuff fit in different BMI categories can be made.

The bigger the healthier: Are the limits of BMI risk changing over time?

PubMed Central

Henderson, R. Max

2006-01-01

The body mass index (BMI) is often used as a predictor of overweight and obesity. There is, however, an important debate among international specialists as to what the risk limits should be, and where the cut-off points should be located. In the United States, for instance, adults with a BMI between 25 and 30 are considered overweight, while adults with a BMI of 30 or higher are considered obese. Nevertheless some researchers, especially in developing countries, claim that the limits established for the US are too permissive, and that the threshold to define obese adults should be set lower for other nationalities and ethnicities. This paper analyzes the mortality risks for different BMI levels of two populations of American adult men. The first population lived during the last quarter of the 19th century and the early 20th century. These men were drawn from a random sample of Union Army veterans who fought during the American Civil War (1861–1865). A contemporary sample of men was drawn from the first wave of the National Health and Nutrition Examination Survey (NHANES I) conducted between 1971 and 1975. The results indicate that the frontier of overweight and obesity are expanding over time, such that the potential risk is nowadays associated with higher levels of BMI. The finding may imply that differences in BMI cut-off points are not only cross ethnic, but also occur for similar ethnicities across time. PMID:16202670

Density and Proximity of Fast Food Restaurants and Body Mass Index Among African Americans

PubMed Central

Regan, Seann D.; Nguyen, Nga; Cromley, Ellen K.; Strong, Larkin L.; Wetter, David W.; McNeill, Lorna H.

2014-01-01

Objectives. The purpose of this study was to address current gaps in the literature by examining the associations of fast food restaurant (FFR) density around the home and FFR proximity to the home, respectively, with body mass index (BMI) among a large sample of African American adults from Houston, Texas. Methods. We used generalized linear models with generalized estimating equations to examine associations of FFR density at 0.5-, 1-, 2-, and 5-mile road network buffers around the home with BMI and associations of the closest FFR to the home with BMI. All models were adjusted for a range of individual-level covariates and neighborhood socioeconomic status. We additionally investigated the moderating effects of household income on these relations. Data were collected from December 2008 to July 2009. Results. FFR density was not associated with BMI in the main analyses. However, FFR density at 0.5, 1, and 2 miles was positively associated with BMI among participants with lower incomes (P ≤ .025). Closer FFR proximity was associated with higher BMI among all participants (P < .001), with stronger associations emerging among those of lower income (P < .013) relative to higher income (P < .014). Conclusions. Additional research with more diverse African American samples is needed, but results supported the potential for the fast food environment to affect BMI among African Americans, particularly among those of lower economic means. PMID:23678913

Association between neighbourhood fast-food and full-service restaurant density and body mass index: a cross-sectional study of Canadian adults.

PubMed

Hollands, Simon; Campbell, M Karen; Gilliland, Jason; Sarma, Sisira

2014-05-07

Frequent fast-food consumption is a well-known risk factor for obesity. This study sought to determine whether the availability of fast-food restaurants has an influence on body mass index (BMI). BMI and individual-level confounding variables were obtained from the 2007-08 Canadian Community Health Survey. Neighbourhood socio-demographic variables were acquired from the 2006 Canadian Census. The geographic locations of all restaurants in Canada were assembled from a validated business registry database. The density of fast-food, full-service and non-chain restaurants per 10,000 individuals was calculated for respondents' forward sortation area. Multivariable regression analyses were conducted to analyze the association between restaurant density and BMI. Fast-food, full-service and non-chain restaurant density variables were statistically significantly associated with BMI. Fast-food density had a positive association whereas full-service and non-chain restaurant density had a negative association with BMI (additional 10 fast-food restaurants per capita corresponded to a weight increase of 1 kilogram; p<0.001). These associations were primarily found in Canada's major urban jurisdictions. This research was the first to investigate the influence of fast-food and full-service restaurant density on BMI using individual-level data from a nationally representative Canadian survey. The finding of a positive association between fast-food restaurant density and BMI suggests that interventions aiming to restrict the availability of fast-food restaurants in local neighbourhoods may be a useful obesity prevention strategy.

Are you what your mother weighs? Evaluating the impact of maternal weight trajectories on youth overweight.

PubMed

Kowaleski-Jones, Lori; Brown, Barbara B; Fan, Jessie X; Smith, Ken R; Zick, Cathleen D

2010-09-01

In this study, we investigate how three alternative measures of maternal body mass index (BMI) relate to youth overweight. We contrast the typical cross-sectional measure of maternal BMI with a longitudinal mean and a standard deviation in maternal BMI. Using National Longitudinal Survey of Youth data, we estimate logistic regressions that relate maternal BMI to the risk of a youth being overweight while controlling for other familial characteristics. Participants in this study are 918 males and 841 females who were age 16-21 and either healthy weight or overweight in 2006. To be eligible for inclusion, teens were 15 years old by December 2006. After comparing several measures of maternal weight, we find that higher mean maternal BMI measured over the life of the adolescent has the strongest relationship with the odds of youth overweight for both male and female adolescents. For boys, a one unit increase in mother's mean BMI increases the odds of being overweight by 16% (OR = 1.16, 95% CI 1.11-1.20) while for girls the increase in the odds of being overweight is 13% (OR = 1.13, 95% CI 1.09-1.18). Our findings suggest that researchers should move beyond static measures of maternal weight when examining the correlates of youth BMI. Maternal weight histories offer additional insights about the youth's home environment that are associated with the risk of a youth being overweight.

Influence of body mass index, gender, and Hispanic ethnicity on physical activity in urban children.

PubMed

Wright, Kynna N

2011-04-01

This community-based participatory research study examined the association between overweight status and activity among Hispanic urban, school-age children. In a sample of 140 children, activities were assessed using the Youth Risk Behavior Survey's questions about physical activity (PA) and team sports. Thirty-nine percent were overweight (body mass index [BMI] >85%). Normal-weight children had higher levels of PA and team sports. Females had lower levels of PA and team sports. Significant associations included BMI and sports team participation, and BMI and Hispanic ethnicity. Nurses should be aware that Hispanic urban children are at risk for lower activity. © 2011, Wiley Periodicals, Inc.

Longitudinal associations between key dietary behaviors and weight gain over time: transitions through the adolescent years.

PubMed

Laska, Melissa N; Murray, David M; Lytle, Leslie A; Harnack, Lisa J

2012-01-01

Previous studies have yielded inconsistent results when documenting the association between key dietary factors and adolescent weight change over time. The purpose of this study was to examine the extent to which changes in adolescent sugar-sweetened beverage (SSB), diet soda, breakfast, and fast-food consumption were associated with changes in BMI and percent body fat (PBF). This study analyzed data from a sample of 693 Minnesota adolescents followed over 2 years. Random coefficient models were used to examine the relationship between dietary intake and BMI and PBF and to separate cross-sectional and longitudinal associations. Adjusting for total physical activity, total energy intake, puberty, race, socioeconomic status, and age, cross-sectional findings indicated that for both males and females, breakfast consumption was significantly and inversely associated with BMI and PBF, and diet soda intake was significantly and positively associated with BMI and PBF among females. In longitudinal analyses, however, there were fewer significant associations. Among males there was evidence of a significant longitudinal association between SSB consumption and PBF; after adjustment for energy intake, an increase of one serving of SSB per day was associated with an increase of 0.7 units of PBF among males. This study adds to previous research through its methodological strengths, including adjustment for physical activity and energy intake assessed using state-of-the-art methods (i.e., accelerometers and 24-h dietary recalls), as well as its evaluation of both BMI and PBF. Additional research is needed to better understand the complex constellation of factors that contribute to adolescent weight gain over time.

Perceived and Police Reported Neighborhood Crime: Linkages to Adolescent Activity Behaviors and Weight Status

PubMed Central

Wall, Melanie; Choo, Tse; Larson, Nicole; Van Riper, David; Neumark-Sztainer, Dianne

2015-01-01

Purpose Inadequate physical activity and obesity during adolescence are areas of public health concern. Questions exist about the role of neighborhoods in the etiology of these problems. This research addressed the relationships of perceived and objective reports of neighborhood crime to adolescent physical activity, screen media use, and BMI. Methods Socioeconomically and racially/ethnically diverse adolescents (N=2,455, 53.4% female) from 20 urban, public middle and high schools in Minneapolis/St. Paul, Minnesota responded to a classroom survey in the EAT 2010 (Eating and Activity in Teens) study. Body mass index (BMI) was measured by research staff. Participants’ mean age was 14.6 (SD=2.0); 82.7% represented racial/ethnic groups other than non-Hispanic white. Linear regressions examined associations between crime perceived by adolescents and crime reported to police and the outcomes of interest (BMI z-scores, physical activity, and screen time). Models were stratified by gender and adjusted for age, race/ethnicity, socioeconomic status, and school. Results BMI was positively associated with perceived crime among girls and boys and with reported crime in girls. For girls, there was an association between higher perceived crime and increased screen time; for boys, between higher reported property crime and reduced physical activity. Perceived crime was associated with reported crime, both property and personal, in both genders. Conclusions Few prior studies of adolescents have studied the association between both perceived and reported crime and BMI. Community-based programs for youth should consider addressing adolescents’ safety concerns along with other perceived barriers to physical activity. Interventions targeting actual crime rates are also important. PMID:26206444

The effect of age, sex and obesity on fundamental motor skills among 4 to 6 years-old children.

PubMed

Vameghi, Roshanak; Shams, Amir; Shamsipour Dehkordi, Parvane

2013-04-01

To examine the effect of age, sex and obesity on Fundamental Motor Skills (FMS) in 4 to 6 years-old children. A total of 400 preschool children (200 boys and 200 girls) between the ages of 4 to 6 years old participated in this research. Subjects were selected through multi-stage cluster random sampling. Fundamental motor skills (FMS) were assessed with using the OSU-SIGMA scale. Body mass index (BMI) was directly measured from height(m)(2)/weight(kg) for each child and based on CDC growth charts, normal weight, overweight and obesity were defined. The results showed that age and sex variables were a significant effect on walking and running skills, but BMI was not significant (P>0.05). Also, these variables had a significant effect on jumping, skipping, hopping and ladder climbing. In both ages, boys in jumping and ladder climbing skills were better than girls, but the girls were better in skipping and hopping skills (P<0.05). Moreover, the results showed that age and BMI variables have a significant effect on stair climbing skill, but sex was not significant (P>0.05). For object control skills, the results showed that age and sex variables were a significant effect on catching and throwing skills, but BMI was not significant (P>0.05). Finally, the age, sex and BMI variables were a significant effect on kicking and sticking skills. This research demonstrated that boys performed better than girls, and both overweight and obese children have lower performance than normal children.

Evaluation of an Online Platform for Multiple Sclerosis Research: Patient Description, Validation of Severity Scale, and Exploration of BMI Effects on Disease Course

PubMed Central

Bove, Riley; Secor, Elizabeth; Healy, Brian C.; Musallam, Alexander; Vaughan, Timothy; Glanz, Bonnie I.; Greeke, Emily; Weiner, Howard L.; Chitnis, Tanuja; Wicks, Paul; De Jager, Philip L.

2013-01-01

Objectives To assess the potential of an online platform, PatientsLikeMe.com (PLM), for research in multiple sclerosis (MS). An investigation of the role of body mass index (BMI) on MS disease course was conducted to illustrate the utility of the platform. Methods First, we compared the demographic characteristics of subjects from PLM and from a regional MS center. Second, we validated PLM’s patient-reported outcome measure (MS Rating Scale, MSRS) against standard physician-rated tools. Finally, we analyzed the relation of BMI to the MSRS measure. Results Compared with 4,039 MS Center patients, the 10,255 PLM members were younger, more educated, and less often male and white. Disease course was more often relapsing remitting, with younger symptom onset and shorter disease duration. Differences were significant because of large sample sizes but small in absolute terms. MSRS scores for 121 MS Center patients revealed acceptable agreement between patient-derived and physician-derived composite scores (weighted kappa = 0.46). The Walking domain showed the highest weighted kappa (0.73) and correlation (rs = 0.86) between patient and physician scores. Additionally, there were good correlations between the patient-reported MSRS composite and walking scores and physician-derived measures: Expanded Disability Status Scale (composite rs = 0.61, walking rs = 0.74), Timed 25 Foot Walk (composite rs = 0.70, walking rs = 0.69), and Ambulation Index (composite rs = 0.81, walking rs = 0.84). Finally, using PLM data, we found a modest correlation between BMI and cross-sectional MSRS (rho = 0.17) and no association between BMI and disease course. Conclusions The PLM population is comparable to a clinic population, and its patient-reported MSRS is correlated with existing clinical instruments. Thus, this online platform may provide a venue for MS investigations with unique strengths (frequent data collection, large sample sizes). To illustrate its applicability, we assessed the role of BMI in MS disease course but did not find a clinically meaningful role for BMI in this setting. PMID:23527256

EarthCube - Earth System Bridge: Spanning Scientific Communities with Interoperable Modeling Frameworks

NASA Astrophysics Data System (ADS)

Peckham, S. D.; DeLuca, C.; Gochis, D. J.; Arrigo, J.; Kelbert, A.; Choi, E.; Dunlap, R.

2014-12-01

In order to better understand and predict environmental hazards of weather/climate, ecology and deep earth processes, geoscientists develop and use physics-based computational models. These models are used widely both in academic and federal communities. Because of the large effort required to develop and test models, there is widespread interest in component-based modeling, which promotes model reuse and simplified coupling to tackle problems that often cross discipline boundaries. In component-based modeling, the goal is to make relatively small changes to models that make it easy to reuse them as "plug-and-play" components. Sophisticated modeling frameworks exist to rapidly couple these components to create new composite models. They allow component models to exchange variables while accommodating different programming languages, computational grids, time-stepping schemes, variable names and units. Modeling frameworks have arisen in many modeling communities. CSDMS (Community Surface Dynamics Modeling System) serves the academic earth surface process dynamics community, while ESMF (Earth System Modeling Framework) serves many federal Earth system modeling projects. Others exist in both the academic and federal domains and each satisfies design criteria that are determined by the community they serve. While they may use different interface standards or semantic mediation strategies, they share fundamental similarities. The purpose of the Earth System Bridge project is to develop mechanisms for interoperability between modeling frameworks, such as the ability to share a model or service component. This project has three main goals: (1) Develop a Framework Description Language (ES-FDL) that allows modeling frameworks to be described in a standard way so that their differences and similarities can be assessed. (2) Demonstrate that if a model is augmented with a framework-agnostic Basic Model Interface (BMI), then simple, universal adapters can go from BMI to a modeling framework's native component interface. (3) Create semantic mappings between modeling frameworks that support semantic mediation. This third goal involves creating a crosswalk between the CF Standard Names and the CSDMS Standard Names (a set of naming conventions). This talk will summarize progress towards these goals.

Do brief motivational interventions reduce drinking game frequency in mandated students? An analysis of data from two randomized controlled trials.

PubMed

Fernandez, Anne C; Yurasek, Ali M; Merrill, Jennifer E; Miller, Mary Beth; Zamboanga, Byron L; Carey, Kate B; Borsari, Brian

2017-02-01

College students frequently engage in drinking games (DGs) and experience a variety of consequences as a result. It is currently unknown whether brief motivational interventions (BMIs) that provide feedback on DG participation can reduce this high risk behavior. This study examined outcome data from 2 randomized clinical trials to examine whether BMIs facilitate change in DG frequency and how these changes may occur. Mandated college students (Trial 1, N = 198, 46% female; Trial 2, N = 412; 32% female) were randomized to BMI or comparison control conditions. Hierarchical linear modeling (HLM) was used to compare the BMI and comparison groups to determine whether the BMI reduced DG participation over time. Percent change talk (PCT) during the discussion of DG during the session was examined as a predictor of change in DG frequency, and gender was examined as a moderator of treatment effects. Controlling for regular drinking frequency, participants who received a BMI did not significantly reduce their DG frequency relative to the comparison group in either sample, and the BMI was equally ineffective at reducing DG behavior for men and women. DG-related PCT during the BMI was associated with lower DG frequency at the second follow-up in both trials. In Trial 1, PCT during the BMI was associated with less steep increases in DG frequency across the course of all follow-ups. Effects of PCT on DG behavior were not moderated by gender. Findings did not support hypothesized reductions in DG participation following a BMI. Future research should explore whether targeted DG-specific interventions could reduce DG participation and the role of in-session client language in facilitating such change. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Explaining the relationship between attachment anxiety, eating behaviour and BMI.

PubMed

Wilkinson, Laura L; Rowe, Angela C; Robinson, Eric; Hardman, Charlotte A

2018-05-05

Previous research indicates that attachment anxiety (fear of abandonment) is predictive of overeating and higher body mass index (BMI). The current study explored the nature of the mechanisms underpinning this relationship. Study 1 assessed the relative contribution of 'emotional eating', 'susceptibility to hunger' and 'uncontrolled eating'. Study 2 assessed whether misperception of emotion and poor emotion management would mediate the relationship between attachment anxiety and stress-induced eating (and then BMI). Two cross-sectional online questionnaire studies were conducted (Study 1 N = 665, & Study 2 N = 548), in UK and US-based samples, which assessed attachment orientation and BMI alongside the potential mediators. The relative contribution of emotional eating, susceptibility to hunger and uncontrolled eating (Study 1) and difficulties in emotion regulation and stress-induced eating (Study 2) as mediators of this relationship were examined. In Study 1, parallel multiple mediation analysis (PROCESS) showed that emotional eating and susceptibility to hunger (but not uncontrolled eating) were significant mediators of the relationship between attachment anxiety and BMI. In Study 2, serial mediation analysis showed that difficulties in 'engaging with goal directed behaviours when upset' and stress-induced eating operated in series to significantly mediate the relationship between attachment anxiety and BMI. These findings suggest that attachment anxious individuals feel less capable in disengaging from negative emotions and go on to try to soothe themselves through eating which has a negative impact on their BMI. There was less support for an explanation of the relationship between attachment anxiety and BMI based around the misperception of emotion. Taken together, the findings highlight attachment anxiety and emotion regulation strategies as key targets for interventions that aim to reduce overeating and excess body weight. Copyright © 2018 Elsevier Ltd. All rights reserved.

Positive predictive value between medical-chart body-mass-index category and obesity versus codes in a claims-data warehouse.

PubMed

Caplan, Eleanor O; Kamble, Pravin S; Harvey, Raymond A; Smolarz, B Gabriel; Renda, Andrew; Bouchard, Jonathan R; Huang, Joanna C

2018-01-01

To evaluate the positive predictive value of claims-based V85 codes for identifying individuals with varying degrees of BMI relative to their measured BMI obtained from medical record abstraction. This was a retrospective validation study utilizing administrative claims and medical chart data from 1 January 2009 to 31 August 2015. Randomly selected samples of patients enrolled in a Medicare Advantage Prescription Drug (MAPD) or commercial health plan and with a V85 claim were identified. The claims-based BMI category (underweight, normal weight, overweight, obese class I-III) was determined via corresponding V85 codes and compared to the BMI category derived from chart abstracted height, weight and/or BMI. The positive predictive values (PPVs) of the claims-based BMI categories were calculated with the corresponding 95% confidence intervals (CIs). The overall PPVs (95% CIs) in the MAPD and commercial samples were 90.3% (86.3%-94.4%) and 91.1% (87.3%-94.9%), respectively. In each BMI category, the PPVs (95% CIs) for the MAPD and commercial samples, respectively, were: underweight, 71.0% (55.0%-87.0%) and 75.9% (60.3%-91.4%); normal, 93.8% (85.4%-100%) and 87.8% (77.8%-97.8%); overweight, 97.4% (92.5%-100%) and 93.5% (84.9%-100%); obese class I, 96.9 (90.9%-100%) and 97.2% (91.9%-100%); obese class II, 97.0% (91.1%-100%) and 93.0% (85.4%-100%); and obese class III, 85.0% (73.3%-96.1%) and 97.1% (91.4%-100%). BMI categories derived from administrative claims, when available, can be used successfully particularly in the context of obesity research.

BMI and attitudes and beliefs about physical activity and nutrition of parents of adolescents with intellectual disabilities.

PubMed

George, V A; Shacter, S D; Johnson, P M

2011-11-01

The purpose of this study was: (1) to evaluate the beliefs, attitudes and behaviours associated with nutrition and physical activity of parents with adolescents with intellectual disabilities (ID); (2) to determine if these variables related to the body mass index (BMI) of the adolescents and the parents' BMI; and (3) to investigate if the parents' perception of their child's weight status was accurate. A survey was used to collect information on BMI and attitudes and beliefs about nutrition and physical activity from parents (n = 207) of adolescents with ID attending schools participating in the Best Buddies Program. Approximately 45% of the adolescents were overweight or obese and over two-thirds of the parents were either overweight or obese. There was a significant difference in child's BMI by parents' description, F(3,158) = 72.75, P < 0.001. Factor analysis on questions on physical activity and nutrition revealed three factors (Factor 1 - Family Healthy Habits, Factor 2 - Parental Role and Factor 3 - Parental Activity) extracting 63% of the variance. The BMI of the adolescents significantly correlated with Factors 2 and 3. Children categorised as having a lower BMI had parents who agreed significantly more (r = -0.22, P < 0.005) with questions about being role models. There was a significant correlation between BMI for both the parents and adolescents and frequency of fast foods purchased. Efforts need to be made to provide parents of adolescents with ID tailored information about how they can assist their child in managing their weight. This information should emphasise to parents the important part they play as role models and as providers for healthy choices for physical activity as well as nutrition. © 2011 The Authors. Journal of Intellectual Disability Research © 2011 Blackwell Publishing Ltd.

Detection of circulating Bmi-1 mRNA in plasma and its potential diagnostic and prognostic value for uterine cervical cancer.

PubMed

Zhang, Xin; Wang, Chuanxin; Wang, Lili; Du, Lutao; Wang, Shun; Zheng, Guixi; Li, Wei; Zhuang, Xuewei; Zhang, Xuhua; Dong, Zhaogang

2012-07-01

Bmi-1 is overexpressed in uterine cervical cancer (UCC) and is found to be associated with adverse clinical characteristics and poor prognosis. However, little information is available on the status of circulating Bmi-1 mRNA in UCC. Because circulating cell-free nucleic acids have emerged as a novel class of markers for cancer detection, our research aims to address this question by detecting the circulating Bmi-1 mRNA and to assess its diagnostic and prognostic potential in UCC. Reverse transcription quantitative real-time PCR method was established to detect the circulating Bmi-1 mRNA in plasma of 109 patients with UCC, 138 patients with cervical intraepithelial neoplasia (CIN) and 80 healthy volunteers, and found that it was significantly increased in UCC compared with CINs and healthy controls (all at p < 0.001). Moreover, its high level was significantly correlated with advanced clinical stage (p < 0.001) and positive lymph nodes metastasis (p = 0.002). The area under the receiver operating characteristic curve (AUC) was 0.881, and the optimal cut-off value was 0.057, providing a sensitivity of 69.7% and a specificity of 95.9%. The AUC for circulating Bmi-1 mRNA showed higher diagnosis capability than that for SCC-Ag (p = 0.035) or CA125 (p < 0.001) currently utilized. Kaplan-Meier analysis demonstrated a correlation between increased circulating Bmi-1 mRNA level and reduced disease-free survival (DFS) (p = 0.001) and overall survival (OS) (p = 0.015). And, Cox analysis indicated that it was an independent prognostic factor for DFS and OS. We conclude that circulating Bmi-1 mRNA may be a potential noninvasive molecular marker for diagnosis and prognosis of UCC. Copyright © 2011 UICC.

Effect of maternal body mass index on hormones in breast milk: a systematic review.

PubMed

Andreas, Nicholas J; Hyde, Matthew J; Gale, Chris; Parkinson, James R C; Jeffries, Suzan; Holmes, Elaine; Modi, Neena

2014-01-01

Maternal Body Mass Index (BMI) is positively associated with infant obesity risk. Breast milk contains a number of hormones that may influence infant metabolism during the neonatal period; these may have additional downstream effects on infant appetite regulatory pathways, thereby influencing propensity towards obesity in later life. To conduct a systematic review of studies examining the association between maternal BMI and the concentration of appetite-regulating hormones in breast milk. Pubmed was searched for studies reporting the association between maternal BMI and leptin, adiponectin, insulin, ghrelin, resistin, obestatin, Peptide YY and Glucagon-Like Peptide 1 in breast milk. Twenty six studies were identified and included in the systematic review. There was a high degree of variability between studies with regard to collection, preparation and analysis of breast milk samples. Eleven of fifteen studies reporting breast milk leptin found a positive association between maternal BMI and milk leptin concentration. Two of nine studies investigating adiponectin found an association between maternal BMI and breast milk adiponectin concentration; however significance was lost in one study following adjustment for time post-partum. No association was seen between maternal BMI and milk adiponectin in the other seven studies identified. Evidence for an association between other appetite regulating hormones and maternal BMI was either inconclusive, or lacking. A positive association between maternal BMI and breast milk leptin concentration is consistently found in most studies, despite variable methodology. Evidence for such an association with breast milk adiponectin concentration, however, is lacking with additional research needed for other hormones including insulin, ghrelin, resistin, obestatin, peptide YY and glucagon-like peptide-1. As most current studies have been conducted with small sample sizes, future studies should ensure adequate sample sizes and standardized methodology.

Occupational physical activity and body mass index (BMI) among Canadian adults: does physical activity at work help to explain the socio-economic patterning of body weight?

PubMed

Barberio, Amanda; McLaren, Lindsay

2011-01-01

The behavioural and socio-cultural processes underlying the association between socio-economic position (SEP) and body mass index (BMI) remain unclear. Occupational physical activity (OPA) is one plausible explanatory variable that has not been previously considered. 1) To examine the association between OPA and BMI, and 2) to examine whether OPA mediates the SEP-BMI association, in a Canadian population-based sample. This cross-sectional study was based on secondary analysis of the 2008 Canadian Community Health Survey data, focusing on adults (age 25-64) working at a job or business (men, n = 1,036; women, n = 936). BMI was based on measured height and weight and we derived a novel indicator of OPA from the National Occupational Classification Career Handbook. Our analytic technique was ordinary least squares regression, adjusting for a range of socio-demographic, health and behavioural covariates. OPA was marginally associated with BMI in women, such that women with medium levels of OPA tended to be lighter than women with low levels of OPA, in adjusted models. No associations between OPA and BMI were detected for males. Baron and Kenny's (1986) three conditions for testing mediation were not satisfied, and thus we were unable to proceed with testing OPA as a mediator. Notwithstanding the small effects observed in women, overall the associations between OPA and BMI were neither clear nor strong, which could reflect conceptual and/or methodological reasons. Future research on this topic might incorporate other plausible explanatory variables (e.g., job-related psychosocial stress) and adopt a prospective design.

Explaining the positive relationship between fourth-grade children's body mass index and energy intake at school-provided meals (breakfast and lunch).

PubMed

Guinn, Caroline H; Baxter, Suzanne D; Royer, Julie A; Hitchcock, David B

2013-05-01

A 2010 publication showed a positive relationship between children's body mass index (BMI) and energy intake at school-provided meals (as assessed by direct meal observations). To help explain that relationship, we investigated 7 outcome variables concerning aspects of school-provided meals: energy content of items selected, number of meal components selected, number of meal components eaten, amounts eaten of standardized school-meal portions, energy intake from flavored milk, energy intake received in trades, and energy content given in trades. Fourth-grade children (N = 465) from Columbia, SC, were observed eating school-provided breakfast and lunch on 1 to 4 days per child. Researchers measured children's weight and height. For daily values at school meals, a generalized linear model was fit with BMI (dependent variable) and the 7 outcome variables, sex, and age (independent variables). BMI was positively related to amounts eaten of standardized school-meal portions (p < .0001) and increased 8.45 kg/m(2) per serving, controlling for other variables in the model. BMI was positively related to energy intake from flavored milk (p = .0041) and increased 0.347 kg/m(2) for every 100 kcal consumed. BMI was negatively related to energy intake received in trades (p = .0003) and decreased 0.468 kg/m(2) for every 100 kcal received. BMI was not significantly related to 4 outcome variables. Knowing that relationships between BMI and actual consumption, not selection, at school-provided meals explained the (previously found) positive relationship between BMI and energy intake at school-provided meals is helpful for school-based obesity interventions. © 2013, American School Health Association.

Existing maternal obesity guidelines may increase inequalities between ethnic groups: a national epidemiological study of 502,474 births in England.

PubMed

Heslehurst, Nicola; Sattar, Naveed; Rajasingam, Daghni; Wilkinson, John; Summerbell, Carolyn D; Rankin, Judith

2012-12-18

Asians are at increased risk of morbidity at a lower body mass index (BMI) than European Whites, particularly relating to metabolic risk. UK maternal obesity guidelines use general population BMI criteria to define obesity, which do not represent the risk of morbidity among Asian populations. This study compares incidence of first trimester obesity using Asian-specific and general population BMI criteria. A retrospective epidemiological study of 502,474 births between 1995 and 2007, from 34 maternity units across England. Data analyses included a comparison of trends over time between ethnic groups using Asian-specific and general population BMI criteria. Logistic regression estimated odds ratios for first trimester obesity among ethnic groups following adjustment for population demographics. Black and South Asian women have a higher incidence of first trimester obesity compared with White women. This is most pronounced for Pakistani women following adjustment for population structure (OR 2.19, 95% C.I. 2.08, 2.31). There is a twofold increase in the proportion of South Asian women classified as obese when using the Asian-specific BMI criteria rather than general population BMI criteria. The incidence of obesity among Black women is increasing at the most rapid rate over time (p=0.01). The twofold increase in maternal obesity among South Asians when using Asian-specific BMI criteria highlights inequalities among pregnant women. A large proportion of South Asian women are potentially being wrongly assigned to low risk care using current UK guidelines to classify obesity and determine care requirements. Further research is required to identify if there is any improvement in pregnancy outcomes if Asian-specific BMI criteria are utilised in the clinical management of maternal obesity to ensure the best quality of care is provided for women irrespective of ethnicity.

Assessment of anthropometric indices among residents of Calabar, South-East Nigeria

PubMed Central

Egbe, Enang Ofem; Asuquo, Otu Akaninyene; Ekwere, Essien Okon; Olufemi, Fasanmade; Ohwovoriole, A. E.

2014-01-01

Background: Obesity is a risk factor for type 2 diabetes mellitus which may be addressed by application of intensive lifestyle interventions. Thus, establishing normative values of anthropometric indices in our environment is crucial. This study aimed to determine normative values of anthropometric indices of nutrition among residents of Calabar. Materials and Methods: This cross sectional observational study recruited residents of Calabar aged between 15-79 years using a multistage sampling method. Trained research assistants collected socio-demographic data and did anthropometric measurements. Results: There were 645 (56.5%) males and 489 (43.1%) females. Males had significantly lower general adiposity and hip circumference (HC) than females while females had significantly lower waist circumference (WC) and waist hip ratio (WHR) than males. The WHR increased with age particularly among males. Body mass index (BMI) also increased with age in both males and females with a peak in the middle age bracket, followed by a decline among the elderly. The mean (SD) BMI was 27.7 (5.0) kg/m2. Males had a mean (SD) BMI of 27.0 (4.4) kg/m2, while females had a mean (SD) BMI of 28.5 (5.5) kg/m2 respectively. WC correlated positively and significantly with BMI and WHR in males and females. WHR correlated positively and significantly with BMI in males and females. Conclusion: There are positive linear inter relationships between the indices of nutrition which is strongest between WC and BMI. In view of the strong independent association of DM with indices of nutrition, it is appropriate to derive normal cut-off values for WC, WHR and BMI nationally. PMID:24944936

Patient Perceptions of Natural Orifice Translumenal Surgery

PubMed Central

Tsang, Melanie E.; Theman, Kirstin; Mercer, Dale; Hopman, Wilma M.; Hookey, Lawrence

2012-01-01

Natural orifice translumenal endoscopic surgery (NOTES) is on the forefront of surgical technique, but existing research has produced mixed results regarding factors associated with interest in the procedure. Our objective was to ascertain patient opinions at a Canadian centre regarding scarless surgery. A survey comprising demographic data (gender, age, body mass index [BMI]), interest in NOTES, impact of increased risk, as well as importance of further research and shorter recovery time was administered to volunteer patients at outpatient general surgery clinics. Nonparametric tests were utilized to examine difference in response by age, sex, BMI, and preexisting scars. Of the 335 participants (57% female, mean age of 54.5 ± 15.9 years, mean BMI of 28.7 ± 6.9), the majority (83%) showed some interest, but this dropped to 38% when additional risk was factored in. Generally, women, those under 50 years of age and those of healthy weight, were more interested than male, older, and/or heavier patients. Most felt that research into NOTES and reduced length of inpatient stay were important (80% and 95%, respectively). Further investigation into objective NOTES outcomes are needed to provide patients adequate data to make an informed choice regarding surgical route. PMID:22482048

Kinematic and neurophysiological consequences of an assisted-force-feedback brain-machine interface training: a case study.

PubMed

Silvoni, Stefano; Cavinato, Marianna; Volpato, Chiara; Cisotto, Giulia; Genna, Clara; Agostini, Michela; Turolla, Andrea; Ramos-Murguialday, Ander; Piccione, Francesco

2013-01-01

In a proof-of-principle prototypical demonstration we describe a new type of brain-machine interface (BMI) paradigm for upper limb motor-training. The proposed technique allows a fast contingent and proportionally modulated stimulation of afferent proprioceptive and motor output neural pathways using operant learning. Continuous and immediate assisted-feedback of force proportional to rolandic rhythm oscillations during actual movements was employed and illustrated with a single case experiment. One hemiplegic patient was trained for 2 weeks coupling somatosensory brain oscillations with force-field control during a robot-mediated center-out motor-task whose execution approaches movements of everyday life. The robot facilitated actual movements adding a modulated force directed to the target, thus providing a non-delayed proprioceptive feedback. Neuro-electric, kinematic, and motor-behavioral measures were recorded in pre- and post-assessments without force assistance. Patient's healthy arm was used as control since neither a placebo control was possible nor other control conditions. We observed a generalized and significant kinematic improvement in the affected arm and a spatial accuracy improvement in both arms, together with an increase and focalization of the somatosensory rhythm changes used to provide assisted-force-feedback. The interpretation of the neurophysiological and kinematic evidences reported here is strictly related to the repetition of the motor-task and the presence of the assisted-force-feedback. Results are described as systematic observations only, without firm conclusions about the effectiveness of the methodology. In this prototypical view, the design of appropriate control conditions is discussed. This study presents a novel operant-learning-based BMI-application for motor-training coupling brain oscillations and force feedback during an actual movement.

Intention Concepts and Brain-Machine Interfacing

PubMed Central

Thinnes-Elker, Franziska; Iljina, Olga; Apostolides, John Kyle; Kraemer, Felicitas; Schulze-Bonhage, Andreas; Aertsen, Ad; Ball, Tonio

2012-01-01

Intentions, including their temporal properties and semantic content, are receiving increased attention, and neuroscientific studies in humans vary with respect to the topography of intention-related neural responses. This may reflect the fact that the kind of intentions investigated in one study may not be exactly the same kind investigated in the other. Fine-grained intention taxonomies developed in the philosophy of mind may be useful to identify the neural correlates of well-defined types of intentions, as well as to disentangle them from other related mental states, such as mere urges to perform an action. Intention-related neural signals may be exploited by brain-machine interfaces (BMIs) that are currently being developed to restore speech and motor control in paralyzed patients. Such BMI devices record the brain activity of the agent, interpret (“decode”) the agent’s intended action, and send the corresponding execution command to an artificial effector system, e.g., a computer cursor or a robotic arm. In the present paper, we evaluate the potential of intention concepts from philosophy of mind to improve the performance and safety of BMIs based on higher-order, intention-related control signals. To this end, we address the distinction between future-, present-directed, and motor intentions, as well as the organization of intentions in time, specifically to what extent it is sequential or hierarchical. This has consequences as to whether these different types of intentions can be expected to occur simultaneously or not. We further illustrate how it may be useful or even necessary to distinguish types of intentions exposited in philosophy, including yes- vs. no-intentions and oblique vs. direct intentions, to accurately decode the agent’s intentions from neural signals in practical BMI applications. PMID:23162504

Operant conditioning of a multiple degree-of-freedom brain-machine interface in a primate model of amputation.

PubMed

Balasubramanian, Karthikeyan; Southerland, Joshua; Vaidya, Mukta; Qian, Kai; Eleryan, Ahmed; Fagg, Andrew H; Sluzky, Marc; Oweiss, Karim; Hatsopoulos, Nicholas

2013-01-01

Operant conditioning with biofeedback has been shown to be an effective method to modify neural activity to generate goal-directed actions in a brain-machine interface. It is particularly useful when neural activity cannot be mathematically mapped to motor actions of the actual body such as in the case of amputation. Here, we implement an operant conditioning approach with visual feedback in which an amputated monkey is trained to control a multiple degree-of-freedom robot to perform a reach-to-grasp behavior. A key innovation is that each controlled dimension represents a behaviorally relevant synergy among a set of joint degrees-of-freedom. We present a number of behavioral metrics by which to assess improvements in BMI control with exposure to the system. The use of non-human primates with chronic amputation is arguably the most clinically-relevant model of human amputation that could have direct implications for developing a neural prosthesis to treat humans with missing upper limbs.

A Brain-Machine Interface Operating with a Real-Time Spiking Neural Network Control Algorithm.

PubMed

Dethier, Julie; Nuyujukian, Paul; Eliasmith, Chris; Stewart, Terry; Elassaad, Shauki A; Shenoy, Krishna V; Boahen, Kwabena

2011-01-01

Motor prostheses aim to restore function to disabled patients. Despite compelling proof of concept systems, barriers to clinical translation remain. One challenge is to develop a low-power, fully-implantable system that dissipates only minimal power so as not to damage tissue. To this end, we implemented a Kalman-filter based decoder via a spiking neural network (SNN) and tested it in brain-machine interface (BMI) experiments with a rhesus monkey. The Kalman filter was trained to predict the arm's velocity and mapped on to the SNN using the Neural Engineering Framework (NEF). A 2,000-neuron embedded Matlab SNN implementation runs in real-time and its closed-loop performance is quite comparable to that of the standard Kalman filter. The success of this closed-loop decoder holds promise for hardware SNN implementations of statistical signal processing algorithms on neuromorphic chips, which may offer power savings necessary to overcome a major obstacle to the successful clinical translation of neural motor prostheses.

Body mass index and physical activity in relation to the incidence of hip fracture in postmenopausal women.

PubMed

Armstrong, Miranda E G; Spencer, Elizabeth A; Cairns, Benjamin J; Banks, Emily; Pirie, Kirstin; Green, Jane; Wright, F Lucy; Reeves, Gillian K; Beral, Valerie

2011-06-01

Hip fracture risk is known to increase with physical inactivity and decrease with obesity, but there is little information on their combined effects. We report on the separate and combined effects of body mass index (BMI) and physical activity on hospital admissions for hip fracture among postmenopausal women in a large prospective UK study. Baseline information on body size, physical activity, and other relevant factors was collected in 1996-2001, and participants were followed for incident hip fractures by record linkage to National Health Service (NHS) hospital admission data. Cox regression was used to calculate adjusted relative risks of hip fracture. Among 925,345 postmenopausal women followed for an average of 6.2 years, 2582 were admitted to hospital with an incident hip fracture. Hip fracture risk increased with decreasing BMI: Compared with obese women (BMI of 30+ kg/m(2) ), relative risks were 1.71 [95% confidence interval (CI) 1.47-1.97)] for BMI of 25.0 to 29.9 kg/m(2) and 2.55 (95% CI 2.22-2.94) for BMI of 20.0 to 24.9 kg/m(2). The increase in fracture risk per unit decrease in BMI was significantly greater among lean women than among overweight women (p < .001). For women in every category of BMI, physical inactivity was associated with an increased risk of hip fracture. There was no significant interaction between the relative effects of BMI and physical activity. For women who reported that they took any exercise versus no exercise, the adjusted relative risk of hip fracture was 0.68 (95% CI 0.62-0.75), with similar results for strenuous exercise. In this large cohort of postmenopausal women, BMI and physical activity had independent effects on hip fracture risk. Copyright © 2011 American Society for Bone and Mineral Research.

Assessment of Under Nutrition of Bangladeshi Adults Using Anthropometry: Can Body Mass Index Be Replaced by Mid-Upper-Arm-Circumference?

PubMed Central

Sultana, Tania; Karim, Md. Nazmul; Ahmed, Tahmeed; Hossain, Md. Iqbal

2015-01-01

Background and Objective Body-mass-index (BMI) is widely accepted as an indicator of nutritional status in adults. Mid-upper-arm-circumference (MUAC) is another anthropometric-measure used primarily among children. The present study attempted to evaluate the use of MUAC as a simpler alternative to BMI cut-off <18.5 to detect adult undernutrition, and thus to suggest a suitable cut-off value. Methods A cross-sectional study in 650 adult attendants of the patients of Dhaka-Hospital, of the International Centre for Diarrheal Disease Research, Bangladesh (icddr,b) was conducted during 2012. Height, weight and MUAC of 260 male and 390 female aged 19–60 years were measured. Curve estimation was done to assess the linearity and correlation of BMI and MUAC. Sensitivity and specificity of MUAC against BMI<18.5 was determined. Separate Receiver-operating-characteristic (ROC) analyses were performed for male and female. Area under ROC curve and Youden's index were generated to aid selection of the most suitable cut-off value of MUAC for undernutrition. A value with highest Youden's index was chosen for cut-off. Results Our data shows strong significant positive correlation (linear) between MUAC and BMI, for males r = 0.81, (p<0.001) and for females r = 0.828, (p<0.001). MUAC cut-off <25.1 cm in males (AUC 0.930) and <23.9 cm in females (AUC 0.930) were chosen separately based on highest corresponding Youden's index. These values best correspond with BMI cut-off for under nutrition (BMI <18.5) in either gender. Conclusion MUAC correlates closely with BMI. For the simplicity and easy to remember MUAC <25 cm for male and <24 cm for female may be considered as a simpler alternative to BMI cut-off <18.5 to detect adult undernutrition. PMID:25875397

Adolescent self-control behavior predicts body weight through the life course: a prospective birth cohort study

PubMed Central

Koike, S; Hardy, R; Richards, M

2016-01-01

Background: Weight gain has become one of the biggest issues for healthy aging in middle- and high-income countries. Self-control of emotional reward cues is an important behavioral factor for regulation of weight gain through voluntary diet control and physical activity. Methods: We tested the associations between teacher-rated self-control at ages 13 and 15 years, and measured body mass index (BMI) between ages 15 and 60–64 years, controlling for confounding factors such as affective symptoms and cognition, using 3873 study members in the Medical Research Council National Survey of Health and Development, also known as the British 1946 birth cohort. Results: Multivariable regression analysis after adjustment for all covariates showed that lower self-control was associated with higher BMI in all measure points (P<0.05). Multilevel modeling using a cubic model showed that there was an association between self-control and BMI at 15 years in females (male: BMI=−0.00 kg m−2 per 1 s.d. on the self-control score (95% confidence interval (CI): −0.12 to 0.11), P =0.94; female: BMI=−0.27 (−0.42 to −0.11), P<0.001). The association became stronger with age in both sexes (BMI=−0.065 (−0.082 to −0.048), P<0.001; BMI=−0.036 (−0.057 to −0.015), P<0.001). By age 60–64 years, the association between self-control and BMI in men had increased to −0.70 (−0.96 to −0.44) and −0.67 (−1.04 to −0.30) in women. Conclusions: Lower adolescent self-control was associated with higher BMI through the life course, and this becomes stronger with age. Investigations to test whether intervention to self-control improves obesity are recommended. PMID:26449420

Interaction between body mass index and hormone-receptor status as a prognostic factor in lymph-node-positive breast cancer

PubMed Central

Chung, Il Yong; Park, Yu Rang; Min, Yul Ha; Lee, Yura; Yoon, Tae In; Sohn, Guiyun; Lee, Sae Byul; Kim, Jisun; Kim, Hee Jeong; Ko, Beom Seok; Son, Byung Ho; Ahn, Sei Hyun

2017-01-01

The aim of this study was to determine the relationship between the body mass index (BMI) at a breast cancer diagnosis and various factors including the hormone-receptor, menopause, and lymph-node status, and identify if there is a specific patient subgroup for which the BMI has an effect on the breast cancer prognosis. We retrospectively analyzed the data of 8,742 patients with non-metastatic invasive breast cancer from the research database of Asan Medical Center. The overall survival (OS) and breast-cancer-specific survival (BCSS) outcomes were compared among BMI groups using the Kaplan-Meier method and Cox proportional-hazards regression models with an interaction term. There was a significant interaction between BMI and hormone-receptor status for the OS (P = 0.029), and BCSS (P = 0.013) in lymph-node-positive breast cancers. Obesity in hormone-receptor-positive breast cancer showed a poorer OS (adjusted hazard ratio [HR] = 1.51, 95% confidence interval [CI] = 0.92 to 2.48) and significantly poorer BCSS (HR = 1.80, 95% CI = 1.08 to 2.99). In contrast, a high BMI in hormone-receptor-negative breast cancer revealed a better OS (HR = 0.44, 95% CI = 0.16 to 1.19) and BCSS (HR = 0.53, 95% CI = 0.19 to 1.44). Being underweight (BMI < 18.50 kg/m2) with hormone-receptor-negative breast cancer was associated with a significantly worse OS (HR = 1.98, 95% CI = 1.00–3.95) and BCSS (HR = 2.24, 95% CI = 1.12–4.47). There was no significant interaction found between the BMI and hormone-receptor status in the lymph-node-negative setting, and BMI did not interact with the menopause status in any subgroup. In conclusion, BMI interacts with the hormone-receptor status in a lymph-node-positive setting, thereby playing a role in the prognosis of breast cancer. PMID:28248981

Parents' Readiness to Change Affects BMI Reduction Outcomes in Adolescents with Polycystic Ovary Syndrome

PubMed Central

Jakubowski, Karen P.; Black, Jessica J.; El Nokali, Nermeen E.; Belendiuk, Katherine A.; Hannon, Tamara S.; Arslanian, Silva A.; Rofey, Dana L.

2012-01-01

Evidence supports the importance of parental involvement for youth's ability to manage weight. This study utilized the stages of change (SOC) model to assess readiness to change weight control behaviors as well as the predictive value of SOC in determining BMI outcomes in forty adolescent-parent dyads (mean adolescent age = 15 ± 1.84 (13–20), BMI = 37 ± 8.60; 70% white) participating in a weight management intervention for adolescent females with polycystic ovary syndrome (PCOS). Adolescents and parents completed a questionnaire assessing their SOC for the following four weight control domains: increasing dietary portion control, increasing fruit and vegetable consumption, decreasing dietary fat, and increasing usual physical activity. Linear regression analyses indicated that adolescent change in total SOC from baseline to treatment completion was not predictive of adolescent change in BMI from baseline to treatment completion. However, parent change in total SOC from baseline to treatment completion was predictive of adolescent change in BMI, (t(24) = 2.15, p = 0.043). Findings support future research which carefully assesses adolescent and parent SOC and potentially develops interventions targeting adolescent and parental readiness to adopt healthy lifestyle goals. PMID:22970350

Body Mass Index and Menstrual Patterns in Dancers.

PubMed

Stracciolini, Andrea; Quinn, Bridget J; Geminiani, Ellen; Kinney, Susan; McCrystal, Tara; Owen, Michael; Pepin, Michael J; Stein, Cynthia J

2016-04-18

Questionnaires were distributed to investigate body mass index (BMI) and menstrual patterns in female dancers aged 12 to 17 years. The study cohort consisted of 105 dancers, mean age 14.8 ± 1.1 years, and mean BMI 19.5 ± 2.3 kg/m 2 In all, 92% were healthy weight for height. First menses age ranged from 10 to 15 years (mean 12.9 ± 1.1 years). A total of 44% reported irregular menses; of those, 14% described irregularity as "every other month," 37% as "every 3 months," and 49% as "skips a month occasionally." A total of 36% of the dancers stop getting their menses during times of increased activity/dance, and 30% have gone >3 months at any time without getting their menses. A significant negative correlation between BMI and age of first menses was found with lower BMI associated with increased age of first menses (linear regression, β = -0.49,P= .021). This study supports an association between BMI and age of menarche among young female dancers. Given bone health reliance on hormonal milieu in female dancers, future research is warranted. © The Author(s) 2016.

Proximity to Food Establishments and Body Mass Index in the Framingham Heart Study Offspring Cohort Over 30 Years

PubMed Central

Block, Jason P.; Christakis, Nicholas A.; O’Malley, A. James; Subramanian, S. V.

2011-01-01

Existing evidence linking residential proximity to food establishments with body mass index (BMI; weight (kg)/height (m)2) has been inconclusive. In this study, the authors assessed the relation between BMI and proximity to food establishments over a 30-year period among 3,113 subjects in the Framingham Heart Study Offspring Cohort living in 4 Massachusetts towns during 1971–2001. The authors used novel data that included repeated measures of BMI and accounted for residential mobility and the appearance and disappearance of food establishments. They calculated proximity to food establishments as the driving distance between each subject’s residence and nearby food establishments, divided into 6 categories. The authors used cross-classified linear mixed models to account for time-varying attributes of individuals and residential neighborhoods. Each 1-km increase in distance to the closest fast-food restaurant was associated with a 0.11-unit decrease in BMI (95% credible interval: −0.20, −0.04). In sex-stratified analyses, this association was present only for women. Other aspects of the food environment were either inconsistently associated or not at all associated with BMI. Contrary to much prior research, the authors did not find a consistent relation between access to fast-food restaurants and individual BMI, necessitating a reevaluation of policy discussions on the anticipated impact of the food environment on weight gain. PMID:21965186

A Prospective Examination of the Mechanisms Linking Childhood Physical Abuse to Body Mass Index in Adulthood.

PubMed

Francis, Melville M; Nikulina, Valentina; Widom, Cathy Spatz

2015-08-01

Previous research has reported associations between childhood physical abuse and body mass index (BMI) in adulthood. This article examined the role of four potential mediators (anxiety, depression, posttraumatic stress, and coping) hypothesized to explain this relationship. Using data from a prospective cohort design, court-substantiated cases of childhood physical abuse (N = 78) and nonmaltreated comparisons (N = 349) were followed up and assessed in adulthood at three time points (1989-1995, 2000-2002, and 2003-2005) when participants were of age 29.2, 39.5, and 41.2, respectively. At age 41, average BMI of the current sample was 29.97, falling between overweight and obese categories. Meditation analyses were conducted, controlling for age, sex, race, smoking, and self-reported weight. Childhood physical abuse was positively associated with subsequent generalized anxiety, major depression, and post-traumatic stress disorder symptoms at age 29.2 and higher levels of depression and posttraumatic stress predicted higher BMI at age 41.2. In contrast, higher levels of anxiety predicted lower BMI. Coping did not mediate between physical abuse and BMI. Anxiety symptoms mediated the relationship between physical abuse and BMI for women, but not for men. These findings illustrate the complexity of studying the consequences of physical abuse, particularly the relationship between psychiatric symptoms and adult health outcomes. © The Author(s) 2015.

Beyond BMI: Conceptual Issues Related to Overweight and Obese Patients

PubMed Central

Müller, Manfred James; Braun, Wiebke; Enderle, Janna; Bosy-Westphal, Anja

2016-01-01

BMI is widely used as a measure of weight status and disease risks; it defines overweight and obesity based on statistical criteria. BMI is a score; neither is it biologically sound nor does it reflect a suitable phenotype worthwhile to study. Because of its limited value, BMI cannot provide profound insight into obesity biology and its co-morbidity. Alternative assessments of weight status include detailed phenotyping by body composition analysis (BCA). However, predicting disease risks, fat mass, and fat-free mass as assessed by validated techniques (i.e., densitometry, dual energy X ray absorptiometry, and bioelectrical impedance analysis) does not exceed the value of BMI. Going beyond BMI and descriptive BCA, the concept of functional body composition (FBC) integrates body components into regulatory systems. FBC refers to the masses of body components, organs, and tissues as well as to their inter-relationships within the context of endocrine, metabolic and immune functions. FBC can be used to define specific phenotypes of obesity, e.g. the sarcopenic-obese patient. Well-characterized obesity phenotypes are a precondition for targeted research (e.g., on the genomics of obesity) and patient-centered care (e.g., adequate treatment of individual obese phenotypes such as the sarcopenic-obese patient). FBC contributes to a future definition of overweight and obesity based on physiological criteria rather than on body weight alone. PMID:27286962

Associations of Personality with Body Mass Index and Obesity in a Large Late Midlife Community Sample

PubMed Central

Wimmelmann, Cathrine Lawaetz; Lund, Rikke; Flensborg-Madsen, Trine; Christensen, Ulla; Osler, Merete; Lykke Mortensen, Erik

2018-01-01

Objective The study examined cross-sectional associations of personality with BMI and obesity among men and women in a large late midlife community sample. Methods The sample comprised 5,286 Danish individuals aged 49–63 years from the Copenhagen Ageing and Midlife Biobank (CAMB) with complete information on measured BMI, personality assessed by the NEO Five Factor Inventory (NEO FFI), and sociodemographic factors including sex, age and educational length. Analysis of variance and logistic regression models were used to investigate associations between personality and BMI as well as obesity. Personality traits were analyzed separately and combined in the same model. Results All personality traits except for neuroticism were significantly associated with BMI, with extraversion (p value ranged from <0.001 to 0.012) and agreeableness (p value ranged from 0.001 to 0.002) being the most consistent predictors of BMI among men and women, respectively. Furthermore, extraversion among men (high scores) (p = 0.016) and agreeableness among women (low scores) (p = 0.026) were the only personality traits significantly associated with obesity when adjusting for duration of education. Conclusion Personality was significantly associated with BMI and to a lesser extent with obesity, and these associations differed between men and women. Also, it was suggested that the interrelations of the five personality traits should be considered in future research of personality and health outcomes. PMID:29631276

The impact of telephonic wellness coaching on weight loss: A "Natural Experiments for Translation in Diabetes (NEXT-D)" study.

PubMed

Schmittdiel, Julie A; Adams, Sara R; Goler, Nancy; Sanna, Rashel S; Boccio, Mindy; Bellamy, David J; Brown, Susan D; Neugebauer, Romain S; Ferrara, Assiamira

2017-02-01

To evaluate the impact of a population-based telephonic wellness coaching program on weight loss. Individual-level segmented regression analysis of interrupted time series data comparing the BMI trajectories in the 12 months before versus the 12 months after initiating coaching among a cohort of Kaiser Permanente Northern California members (n = 954) participating in The Permanente Medical Group Wellness Coaching program in 2011. The control group was a 20:1 propensity-score matched control group (n = 19,080) matched with coaching participants based on baseline demographic and clinical characteristics. Wellness coaching participants had a significant upward trend in BMI in the 12 months before their first wellness coaching session and a significant downward trend in BMI in the 12 months after their first session equivalent to a clinically significant reduction of greater than one unit of baseline BMI (P < 0.01 for both). The control group did not have statistically significant decreases in BMI during the post-period. Wellness coaching has a positive impact on BMI reduction that is both statistically and clinically significant. Future research and quality improvement efforts should focus on disseminating wellness coaching for weight loss in patients with diabetes and those at risk for developing the disease. © 2017 The Authors. Obesity published by Wiley Periodicals, Inc. on behalf of The Obesity Society (TOS).

Baseline Obesity Status Modifies Effectiveness of Adapted Diabetes Prevention Program Lifestyle Interventions for Weight Management in Primary Care

PubMed Central

Azar, Kristen M. J.; Xiao, Lan; Ma, Jun

2013-01-01

Objective. To examine whether baseline obesity severity modifies the effects of two different, primary care-based, technology-enhanced lifestyle interventions among overweight or obese adults with prediabetes and/or metabolic syndrome. Patients and Methods. We compared mean differences in changes from baseline to 15 months in clinical measures of general and central obesity among participants randomized to usual care alone (n = 81) or usual care plus a coach-led group (n = 79) or self-directed individual (n = 81) intervention, stratified by baseline body mass index (BMI) category. Results. Participants with baseline BMI 35+ had greater reductions in mean BMI, body weight (as percentage change), and waist circumference in the coach-led group intervention, compared to usual care and the self-directed individual intervention (P < 0.05 for all). In contrast, the self-directed intervention was more effective than usual care only among participants with baseline BMIs between 25 ≤ 35. Mean weight loss exceeded 5% in the coach-led intervention regardless of baseline BMI category, but this was achieved only among self-directed intervention participants with baseline BMIs <35. Conclusions. Baseline BMI may influence behavioral weight-loss treatment effectiveness. Researchers and clinicians should take an individual's baseline BMI into account when developing or recommending lifestyle focused treatment strategy. This trial is registered with ClinicalTrials.gov NCT00842426. PMID:24369008

Relationship of pressure to be thin with gains in body weight and fat mass in adolescents.

PubMed

Suelter, C S; Schvey, N; Kelly, N R; Shanks, M; Thompson, K A; Mehari, R; Brady, S; Yanovski, S Z; Melby, C L; Tanofsky-Kraff, M; Yanovski, J A; Shomaker, L B

2018-01-01

Sociocultural pressure to be thin is commonly reported by adolescents; yet, to what extent such pressure is associated with weight gain has not been evaluated longitudinally. Examine whether pressure to be thin was positively associated with weight and fat gain in adolescents. Participants were 196 healthy adolescent (age 15 ± 1 years old) girls (65%) and boys of varying weights (BMI 25 ± 7 kg/m 2 ) studied at baseline and 1-year follow-up. At baseline, adolescents and their mothers reported pressure to be thin by questionnaire. At baseline and follow-up, BMI was calculated, and fat mass was assessed with air displacement plethysmography. Multiple regression was used to examine associations between baseline pressure to be thin and 1-year changes in BMI and fat mass. Accounting for multiple covariates, including baseline BMI or fat, adolescent-reported pressure from parents and peers and mother-reported pressure toward their teen were associated with greater gains in either adolescent BMI or fat (ps < .05). Adolescent weight status was a moderator of multiple effects (ps < .05). Parental and peer pressure to be thin were associated with increases in BMI and fat mass during adolescence, particularly in heavier adolescents. Further research is necessary to clarify how this association operates reciprocally and to identify underlying explanatory mechanisms. © 2016 World Obesity Federation.

Sexual Orientation Disparities in Weight Status in Adolescence: Findings From a Prospective Study

PubMed Central

Austin, S. Bryn; Ziyadeh, Najat J.; Corliss, Heather L.; Haines, Jess; Rockett, Helaine; Wypij, David; Field, Alison E.

2009-01-01

A growing number of studies among adult women have documented disparities in overweight adversely affecting lesbian and bisexual women, but few studies have examined sexual orientation-related patterns in weight status among men or adolescents. We examined sexual orientation group trends in body mass index (BMI; kg/m2), BMI Z-scores, and overweight using 56,990 observations from 13,785 adolescent females and males in the Growing Up Today Study, a large prospective cohort of U.S. youth. Participants provided self-reported information from six waves of questionnaire data collection from 1998 to 2005. Gender-stratified linear regression models were used to estimate BMI and BMI Z-score and modified Poisson regression models to estimate risk ratios (RR) for overweight, controlling for age and race/ethnicity, with heterosexuals as the referent group. Among females, we observed fairly consistently elevated BMI in all sexual orientation minority groups relative to heterosexual peers. In contrast, among males we documented a sexual-orientation-by-age interaction indicating steeper increases in BMI with age from early to late adolescence in heterosexuals relative to sexual orientation minorities. Additional prospective research is needed to understand the determinants of observed sexual orientation disparities and to inform appropriate preventive and treatment interventions. The long-term health consequences of overweight are well-documented and over time are likely to exact a high toll on populations with elevated rates. PMID:19300430

The impact of command signal power distribution, processing delays, and speed scaling on neurally-controlled devices.

PubMed

Marathe, A R; Taylor, D M

2015-08-01

Decoding algorithms for brain-machine interfacing (BMI) are typically only optimized to reduce the magnitude of decoding errors. Our goal was to systematically quantify how four characteristics of BMI command signals impact closed-loop performance: (1) error magnitude, (2) distribution of different frequency components in the decoding errors, (3) processing delays, and (4) command gain. To systematically evaluate these different command features and their interactions, we used a closed-loop BMI simulator where human subjects used their own wrist movements to command the motion of a cursor to targets on a computer screen. Random noise with three different power distributions and four different relative magnitudes was added to the ongoing cursor motion in real time to simulate imperfect decoding. These error characteristics were tested with four different visual feedback delays and two velocity gains. Participants had significantly more trouble correcting for errors with a larger proportion of low-frequency, slow-time-varying components than they did with jittery, higher-frequency errors, even when the error magnitudes were equivalent. When errors were present, a movement delay often increased the time needed to complete the movement by an order of magnitude more than the delay itself. Scaling down the overall speed of the velocity command can actually speed up target acquisition time when low-frequency errors and delays are present. This study is the first to systematically evaluate how the combination of these four key command signal features (including the relatively-unexplored error power distribution) and their interactions impact closed-loop performance independent of any specific decoding method. The equations we derive relating closed-loop movement performance to these command characteristics can provide guidance on how best to balance these different factors when designing BMI systems. The equations reported here also provide an efficient way to compare a diverse range of decoding options offline.

The impact of command signal power distribution, processing delays, and speed scaling on neurally-controlled devices

NASA Astrophysics Data System (ADS)

Marathe, A. R.; Taylor, D. M.

2015-08-01

Objective. Decoding algorithms for brain-machine interfacing (BMI) are typically only optimized to reduce the magnitude of decoding errors. Our goal was to systematically quantify how four characteristics of BMI command signals impact closed-loop performance: (1) error magnitude, (2) distribution of different frequency components in the decoding errors, (3) processing delays, and (4) command gain. Approach. To systematically evaluate these different command features and their interactions, we used a closed-loop BMI simulator where human subjects used their own wrist movements to command the motion of a cursor to targets on a computer screen. Random noise with three different power distributions and four different relative magnitudes was added to the ongoing cursor motion in real time to simulate imperfect decoding. These error characteristics were tested with four different visual feedback delays and two velocity gains. Main results. Participants had significantly more trouble correcting for errors with a larger proportion of low-frequency, slow-time-varying components than they did with jittery, higher-frequency errors, even when the error magnitudes were equivalent. When errors were present, a movement delay often increased the time needed to complete the movement by an order of magnitude more than the delay itself. Scaling down the overall speed of the velocity command can actually speed up target acquisition time when low-frequency errors and delays are present. Significance. This study is the first to systematically evaluate how the combination of these four key command signal features (including the relatively-unexplored error power distribution) and their interactions impact closed-loop performance independent of any specific decoding method. The equations we derive relating closed-loop movement performance to these command characteristics can provide guidance on how best to balance these different factors when designing BMI systems. The equations reported here also provide an efficient way to compare a diverse range of decoding options offline.

Post-stroke balance rehabilitation under multi-level electrotherapy: a conceptual review

PubMed Central

Dutta, Anirban; Lahiri, Uttama; Das, Abhijit; Nitsche, Michael A.; Guiraud, David

2014-01-01

Stroke is caused when an artery carrying blood from heart to an area in the brain bursts or a clot obstructs the blood flow thereby preventing delivery of oxygen and nutrients. About half of the stroke survivors are left with some degree of disability. Innovative methodologies for restorative neurorehabilitation are urgently required to reduce long-term disability. The ability of the nervous system to respond to intrinsic or extrinsic stimuli by reorganizing its structure, function, and connections is called neuroplasticity. Neuroplasticity is involved in post-stroke functional disturbances, but also in rehabilitation. It has been shown that active cortical participation in a closed-loop brain machine interface (BMI) can induce neuroplasticity in cortical networks where the brain acts as a controller, e.g., during a visuomotor task. Here, the motor task can be assisted with neuromuscular electrical stimulation (NMES) where the BMI will act as a real-time decoder. However, the cortical control and induction of neuroplasticity in a closed-loop BMI is also dependent on the state of brain, e.g., visuospatial attention during visuomotor task performance. In fact, spatial neglect is a hidden disability that is a common complication of stroke and is associated with prolonged hospital stays, accidents, falls, safety problems, and chronic functional disability. This hypothesis and theory article presents a multi-level electrotherapy paradigm toward motor rehabilitation in virtual reality that postulates that while the brain acts as a controller in a closed-loop BMI to drive NMES, the state of brain can be can be altered toward improvement of visuomotor task performance with non-invasive brain stimulation (NIBS). This leads to a multi-level electrotherapy paradigm where a virtual reality-based adaptive response technology is proposed for post-stroke balance rehabilitation. In this article, we present a conceptual review of the related experimental findings. PMID:25565937

The impact of age and sex adjusted body mass index (ISO-BMI) in obese versus non-obese children and adolescents with cholecystectomy.

PubMed

Kiuru, Eveliina; Kokki, Hannu; Juvonen, Petri; Lintula, Hannu; Paajanen, Hannu; Gissler, Mika; Eskelinen, Matti

2014-01-01

The impact of the age and sex adjusted body mass index (ISO-BMI) in the obese vs. non-obese children and adolescents with cholecystectomy for cholelithias is rarely reported. The national database was searched for cholecystectomies performed in paediatric patients between 1997 and 2011, and the 59 paediatric and adolescent patients having cholecystectomy in the Kuopio University Hospital district were divided in two groups by age and sex adjusted BMI (ISO-BMI) using the cut-off point of overweight (ISO-BMI 25 kg/m(2)) based on the Finnish growth standards. Nationwide a total of 840 cholecystectomies were performed during the 15 years study period in Finland, most of which included females (77%), resulting in a mean of annual frequency of 4.8 (range: 3.9-6.1) procedures/100,000 population. In the study sample, most of the patients with the cholelithiasis were female (50/59, 85%). The gender distribution was equal among the younger patients, but among adolescents 6/52 (12%) of the patients with cholelithiasis were boys and 46/52 (88%) of the patients with cholelithiasis were girls. Obesity did not affect on operative parameters. The median operative time was 70 min (range, 30-155) and 66 min (44-130) in the high ISO-BMI-group. The recovery was similar in the two groups: the median length of hospital stay was 4 days in both groups. The patients in the low ISO-BMI-group vs. high ISO-BMI-group had a trend of higher serum bilirubin (p=0.16) and serum AFOS values (p=0.19). In the histological examination of the gallbladders 19/28 (68%) patients in the low ISO-BMI-group had inflammation vs. 26/31 (84%) patients in the high ISO-BMI-group (p=0.15). Our results between obese and non-obese children and adolescents with cholelithiasis are not statistically significant. The obese adolescents with female gender are in greater risk for cholelithiasis. Copyright © 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Trajectories of growth in body mass index across childhood: Associations with maternal and paternal employment.

PubMed

Morrissey, Taryn W

2013-10-01

Research links mothers' employment to higher body mass index (BMI), a measure of weight-for-height, among their children. However, how maternal employment patterns relate to their children's BMI trajectories, and the role that fathers' employment plays in when and at what rate children grow, remain unclear. With data on children from 2 to 15 years of age living in two-parent families from the U.S. NICHD's Study of Early Child Care and Youth Development (N = 1107), individual growth models are used to describe American children's BMI trajectories as predicted by maternal and paternal employment characteristics. Results indicate that, by age 15, children's BMIs are, on average, nearly one-half of a standard deviation above recommended levels, and the majority of growth occurs during the preschool period. The duration of maternal employment, and combined measures of maternal and paternal employment duration, are both associated with higher child BMI across childhood. Associations are small but cumulative. Notably, the association between the duration of time children lived in dual-earner families and child BMI is larger than that between maternal employment duration alone and children's BMI, which is strongest during the preschool period. Combined measures of maternal and paternal employment intensity, defined as the number of periods both parents worked 35 or more hours per week, are associated with higher child BMI during the preschool period only. Findings highlight the importance of taking into account both parents' employment characteristics in investigating children's physical development. Copyright © 2012 Elsevier Ltd. All rights reserved.

Body mass index affects knee joint mechanics during gait differently with and without moderate knee osteoarthritis.

PubMed

Harding, Graeme T; Hubley-Kozey, Cheryl L; Dunbar, Michael J; Stanish, William D; Astephen Wilson, Janie L

2012-11-01

Obesity is a highly cited risk factor for knee osteoarthritis (OA), but its role in knee OA pathogenesis and progression is not as clear. Excess weight may contribute to an increased mechanical burden and altered dynamic movement and loading patterns at the knee. The objective of this study was to examine the interacting role of moderate knee OA disease presence and obesity on knee joint mechanics during gait. Gait analysis was performed on 104 asymptomatic and 140 individuals with moderate knee OA. Each subject group was divided into three body mass categories based on body mass index (BMI): healthy weight (BMI<25), overweight (25≤BMI≤30), and obese (BMI>30). Three-dimensional knee joint angles and net external knee joint moments were calculated and waveform principal component analysis (PCA) was applied to extract major patterns of variability from each. PC scores for major patterns were compared between groups using a two-factor ANOVA. Significant BMI main effects were found in the pattern of the knee adduction moment, the knee flexion moment, and the knee rotation moment during gait. Two interaction effects between moderate OA disease presence and BMI were also found that described different changes in the knee flexion moment and the knee flexion angle with increased BMI with and without knee OA. Our results suggest that increased BMI is associated with different changes in biomechanical patterns of the knee joint during gait depending on the presence of moderate knee OA. Copyright © 2012 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Determinants of Body Mass Index and Intelligence Quotient of Elementary School Children in Mountain Area of Nepal: An Explorative Study.

PubMed

Ranabhat, Chhabi; Kim, Chun-Bae; Park, Myung Bae; Kim, Chang Soo; Freidoony, Leila

2016-02-03

The physical growth and cognitive development of elementary school children are very crucial and this group is large in number but has little research dedicated to it. The physical growth and cognitive development of children occur simultaneously and can be measured by body mass index (BMI) and intelligence quotient (IQ). Previous studies could not sufficiently focus on both aspects. The aim of this study was to identify determinants of BMI and IQ of students in two elementary schools in the Humla district of Nepal. Two randomly selected elementary schools and all children available there (n = 173) participated in the study. BMI was calculated with the objective of proper measurement of height and weight of the children. Likewise, the updated universal nonverbal intelligence test (UNIT) was applied for IQ. Descriptive statistics, t-test, analysis of variance and multiple linear regressions were used when appropriate. Study findings showed that one-tenth of the children had grade 2 thinness (-2SD) and about one-third had poor IQ (<85). The age of the children (p < 0.05) and household economic status (p < 0.001) were significant for the BMI. Likewise, frequencies of illness in the previous year, mother's education (p < 0.05) and father's education (p < 0.001) were significant factors for the IQ score. More commonly, BMI and IQ scores were significantly lower in the ultra-poor group. Economic status and parent education are still major determinants of IQ and BMI in these students. Special programs and strategies should be launched to improve the poor ranking of IQ and BMI.

Association between Dental Caries and BMI in Children: A Systematic Review and Meta-Analysis.

PubMed

Chen, Dongru; Zhi, Qinghui; Zhou, Yan; Tao, Ye; Wu, Liping; Lin, Huancai

2018-01-01

Research on the association between dental caries and body mass index (BMI) in children has shown contradictory results; thus we aimed to examine the association between dental caries and the full range of BMI classes among children. We comprehensively searched PubMed, Embase, and the Cochrane Library for studies published prior to March 2017. Articles comparing dental caries among the full range of BMI classes for children below 18 years of both genders were included. Fourteen studies were eligible for this study. Basic information - i.e., first author, published year, study design, country, sample size, age, type of dental caries index and BMI, main results and conclusions, and means and standard deviations of the dental caries indexes used - was pooled. The weighted mean differences and corresponding 95% confidence intervals for dental caries between children with abnormal weight and those with normal weight were analyzed. Generally, no significant differences in caries were found between any abnormal-weight group and the normal-weight group for both primary and permanent teeth. Sensitivity analyses showed that the obese group had more caries than the normal-weight group in their primary teeth. Significantly more caries was found among the overweight and obese children in both primary and permanent teeth in high-income countries, but not in low- and middle-income countries. We recommend that further studies use suitable sample sizes, unify the criteria for BMI categorization and the dental caries index, and investigate the confounding factors that might influence dental caries and BMI. © 2018 S. Karger AG, Basel.

Associations between major chain fast-food outlet availability and change in body mass index: a longitudinal observational study of women from Victoria, Australia

PubMed Central

Thornton, Lukar E; Olstad, Dana Lee; Cerin, Ester; Ball, Kylie

2017-01-01

Objectives The residential neighbourhood fast-food environment has the potential to lead to increased levels of obesity by providing opportunities for residents to consume energy-dense products. This longitudinal study aimed to examine whether change in body mass index (BMI) differed dependent on major chain fast-food outlet availability among women residing in disadvantaged neighbourhoods. Setting Eighty disadvantaged neighbourhoods in Victoria, Australia. Participants Sample of 882 women aged 18–46 years at baseline (wave I: 2007/2008) who remained at the same residential location at all three waves (wave II: 2010/2011; wave III: 2012/2013) of the Resilience for Eating and Activity Despite Inequality study. Primary outcome BMI based on self-reported height and weight at each wave. Results There was no evidence of an interaction between time and the number of major chain fast-food outlets within 2 (p=0.88), 3 (p=0.66) or 5 km (p=0.24) in the multilevel models of BMI. Furthermore, there was no evidence of an interaction between time and change in availability at any distance and BMI. Conclusions Change in BMI was not found to differ by residential major chain fast-food outlet availability among Victorian women residing in disadvantaged neighbourhoods. It may be that exposure to fast-food outlets around other locations regularly visited influence change in BMI. Future research needs to consider what environments are the key sources for accessing and consuming fast food and how these relate to BMI and obesity risk. PMID:29042381

Local-learning-based neuron selection for grasping gesture prediction in motor brain machine interfaces

NASA Astrophysics Data System (ADS)

Xu, Kai; Wang, Yiwen; Wang, Yueming; Wang, Fang; Hao, Yaoyao; Zhang, Shaomin; Zhang, Qiaosheng; Chen, Weidong; Zheng, Xiaoxiang

2013-04-01

Objective. The high-dimensional neural recordings bring computational challenges to movement decoding in motor brain machine interfaces (mBMI), especially for portable applications. However, not all recorded neural activities relate to the execution of a certain movement task. This paper proposes to use a local-learning-based method to perform neuron selection for the gesture prediction in a reaching and grasping task. Approach. Nonlinear neural activities are decomposed into a set of linear ones in a weighted feature space. A margin is defined to measure the distance between inter-class and intra-class neural patterns. The weights, reflecting the importance of neurons, are obtained by minimizing a margin-based exponential error function. To find the most dominant neurons in the task, 1-norm regularization is introduced to the objective function for sparse weights, where near-zero weights indicate irrelevant neurons. Main results. The signals of only 10 neurons out of 70 selected by the proposed method could achieve over 95% of the full recording's decoding accuracy of gesture predictions, no matter which different decoding methods are used (support vector machine and K-nearest neighbor). The temporal activities of the selected neurons show visually distinguishable patterns associated with various hand states. Compared with other algorithms, the proposed method can better eliminate the irrelevant neurons with near-zero weights and provides the important neuron subset with the best decoding performance in statistics. The weights of important neurons converge usually within 10-20 iterations. In addition, we study the temporal and spatial variation of neuron importance along a period of one and a half months in the same task. A high decoding performance can be maintained by updating the neuron subset. Significance. The proposed algorithm effectively ascertains the neuronal importance without assuming any coding model and provides a high performance with different decoding models. It shows better robustness of identifying the important neurons with noisy signals presented. The low demand of computational resources which, reflected by the fast convergence, indicates the feasibility of the method applied in portable BMI systems. The ascertainment of the important neurons helps to inspect neural patterns visually associated with the movement task. The elimination of irrelevant neurons greatly reduces the computational burden of mBMI systems and maintains the performance with better robustness.

A robust adaptive denoising framework for real-time artifact removal in scalp EEG measurements

NASA Astrophysics Data System (ADS)

Kilicarslan, Atilla; Grossman, Robert G.; Contreras-Vidal, Jose Luis

2016-04-01

Objective. Non-invasive measurement of human neural activity based on the scalp electroencephalogram (EEG) allows for the development of biomedical devices that interface with the nervous system for scientific, diagnostic, therapeutic, or restorative purposes. However, EEG recordings are often considered as prone to physiological and non-physiological artifacts of different types and frequency characteristics. Among them, ocular artifacts and signal drifts represent major sources of EEG contamination, particularly in real-time closed-loop brain-machine interface (BMI) applications, which require effective handling of these artifacts across sessions and in natural settings. Approach. We extend the usage of a robust adaptive noise cancelling (ANC) scheme ({H}∞ filtering) for removal of eye blinks, eye motions, amplitude drifts and recording biases simultaneously. We also characterize the volume conduction, by estimating the signal propagation levels across all EEG scalp recording areas due to ocular artifact generators. We find that the amplitude and spatial distribution of ocular artifacts vary greatly depending on the electrode location. Therefore, fixed filtering parameters for all recording areas would naturally hinder the true overall performance of an ANC scheme for artifact removal. We treat each electrode as a separate sub-system to be filtered, and without the loss of generality, they are assumed to be uncorrelated and uncoupled. Main results. Our results show over 95-99.9% correlation between the raw and processed signals at non-ocular artifact regions, and depending on the contamination profile, 40-70% correlation when ocular artifacts are dominant. We also compare our results with the offline independent component analysis and artifact subspace reconstruction methods, and show that some local quantities are handled better by our sample-adaptive real-time framework. Decoding performance is also compared with multi-day experimental data from 2 subjects, totaling 19 sessions, with and without {H}∞ filtering of the raw data. Significance. The proposed method allows real-time adaptive artifact removal for EEG-based closed-loop BMI applications and mobile EEG studies in general, thereby increasing the range of tasks that can be studied in action and context while reducing the need for discarding data due to artifacts. Significant increase in decoding performances also justify the effectiveness of the method to be used in real-time closed-loop BMI applications.

A continuously growing web-based interface structure databank

NASA Astrophysics Data System (ADS)

Erwin, N. A.; Wang, E. I.; Osysko, A.; Warner, D. H.

2012-07-01

The macroscopic properties of materials can be significantly influenced by the presence of microscopic interfaces. The complexity of these interfaces coupled with the vast configurational space in which they reside has been a long-standing obstacle to the advancement of true bottom-up material behavior predictions. In this vein, atomistic simulations have proven to be a valuable tool for investigating interface behavior. However, before atomistic simulations can be utilized to model interface behavior, meaningful interface atomic structures must be generated. The generation of structures has historically been carried out disjointly by individual research groups, and thus, has constituted an overlap in effort across the broad research community. To address this overlap and to lower the barrier for new researchers to explore interface modeling, we introduce a web-based interface structure databank (www.isdb.cee.cornell.edu) where users can search, download and share interface structures. The databank is intended to grow via two mechanisms: (1) interface structure donations from individual research groups and (2) an automated structure generation algorithm which continuously creates equilibrium interface structures. In this paper, we describe the databank, the automated interface generation algorithm, and compare a subset of the autonomously generated structures to structures currently available in the literature. To date, the automated generation algorithm has been directed toward aluminum grain boundary structures, which can be compared with experimentally measured population densities of aluminum polycrystals.

Questionnaire and laboratory measures of eating behavior: Associations with energy intake and BMI in a community sample of working adults

PubMed Central

French, Simone A; Mitchell, Nathan R; Wolfson, Julian; Finlayson, Graham; Blundell, John E; Jeffery, Robert W

2013-01-01

Purpose The present research compared a self-report measure of usual eating behaviors with two laboratory-based behavioral measures of food reward and food preference. Methods Eating behaviors were measured among 233 working adults. A self-report measure was the Three Factor Eating Questionnaire (TFEQ) Restraint, Disinhibition and Hunger subscales. Laboratory measures were the (RVF) and Explicit Liking (EL) and Implicit Wanting (IW) for high fat food. Outcome measures were body mass index (BMI), and energy intake measured using three 24-hour dietary recalls. Results Significant bivariate associations were observed between each of the eating behavior measures and energy intake, but only Disinhibition and Hunger were associated with BMI. Multiple regression results showed RVF and EL and IW predicted energy intake independent of the TFEQ scales but did not predict BMI. Conclusion Laboratory and self-report measures capture unique aspects of individual differences in eating behaviors that are associated with energy intake. PMID:24096082

Usual energy intake mediates the relationship between food reinforcement and BMI.

PubMed

Epstein, Leonard H; Carr, Katelyn A; Lin, Henry; Fletcher, Kelly D; Roemmich, James N

2012-09-01

The relative reinforcing value of food (RRV(food)) is positively associated with energy consumed and overweight status. One hypothesis relating these variables is that food reinforcement is related to BMI through usual energy intake. Using a sample of two hundred fifty-two adults of varying weight and BMI levels, results showed that usual energy intake mediated the relationship between RRV(food) and BMI (estimated indirect effect = 0.0027, bootstrapped 95% confidence intervals (CIs) 0.0002-0.0068, effect ratio = 0.34), controlling for age, sex, minority status, education, and reinforcing value of reading (RRV(reading)). Laboratory and usual energy intake were correlated (r = 0.24, P < 0.001), indicating that laboratory energy intake could provide an index of eating behavior in the natural environment. The mediational relationship observed suggests that increasing or decreasing food reinforcement could influence body weight by altering food consumption. Research is needed to develop methods of modifying RRV(food) to determine experimentally whether manipulating food reinforcement would result in changes in body weight.

Healthy Body and Healthy Mind: A Study of the Relationship between BMI and Soldier Resilience

DTIC Science & Technology

2011-04-01

confidence (Ensel & Lin, 2003). This could be due to the physiological benefits the body gains from physical fitness such as better oxygen intake , more...this general term may be translated in different ways. Weight lifters are physically fit, as are marathoners, and as are soccer players; however, the...mass index (BMI), and provides a means to assess physical fitness by calculating the body’s fat percentage. Deurenberg et al. (1991) researched the

Associations Between Adolescents' Weight and Maladjustment Differ With Deviation From Weight Norms in Social Contexts.

PubMed

Sutter, Carolyn; Nishina, Adrienne; Witkow, Melissa R; Bellmore, Amy

2016-09-01

In line with the reflected self-appraisal hypothesis, previous research finds associations between weight and maladjustment are strongest when there is a mismatch between individuals' weight and the weight norm of their social contexts. However, research has not considered associations in more proximal social contexts. We examined differences in associations between weight and maladjustment for 2 proximal social contexts: grade-level peers and friendship groups. We used sixth-graders (N = 565; Mage  = 12 years) self-reported height and weight (used to calculate body mass index (BMI) z-score), experiences of peer victimization, and depressive symptoms. Deviation from the normative weight was calculated as the students' BMI z-score minus the average BMI z-score for the context (grade-level peers or friendship group). Considering deviations from grade-level peers, greater BMI z-scores were associated with more self-reported peer victimization only for students above the weight norm. For the friendship group, greater weight was associated with more self-reported depressive symptoms only for those who were above the normative weight. Being heavier during adolescence may be especially problematic for students who differ from the norm in their proximal social contexts. Intervention efforts focused on weight and maladjustment may want to consider the contexts involved in adolescents' self-appraisals. © 2016, American School Health Association.

The use of measures of obesity in childhood for predicting obesity and the development of obesity-related diseases in adulthood: a systematic review and meta-analysis.

PubMed

Simmonds, Mark; Burch, Jane; Llewellyn, Alexis; Griffiths, Claire; Yang, Huiqin; Owen, Christopher; Duffy, Steven; Woolacott, Nerys

2015-06-01

It is uncertain which simple measures of childhood obesity are best for predicting future obesity-related health problems and the persistence of obesity into adolescence and adulthood. To investigate the ability of simple measures, such as body mass index (BMI), to predict the persistence of obesity from childhood into adulthood and to predict obesity-related adult morbidities. To investigate how accurately simple measures diagnose obesity in children, and how acceptable these measures are to children, carers and health professionals. Multiple sources including MEDLINE, EMBASE and The Cochrane Library were searched from 2008 to 2013. Systematic reviews and a meta-analysis were carried out of large cohort studies on the association between childhood obesity and adult obesity; the association between childhood obesity and obesity-related morbidities in adulthood; and the diagnostic accuracy of simple childhood obesity measures. Study quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) and a modified version of the Quality in Prognosis Studies (QUIPS) tool. A systematic review and an elicitation exercise were conducted on the acceptability of the simple measures. Thirty-seven studies (22 cohorts) were included in the review of prediction of adult morbidities. Twenty-three studies (16 cohorts) were included in the tracking review. All studies included BMI. There were very few studies of other measures. There was a strong positive association between high childhood BMI and adult obesity [odds ratio 5.21, 95% confidence interval (CI) 4.50 to 6.02]. A positive association was found between high childhood BMI and adult coronary heart disease, diabetes and a range of cancers, but not stroke or breast cancer. The predictive accuracy of childhood BMI to predict any adult morbidity was very low, with most morbidities occurring in adults who were of healthy weight in childhood. Predictive accuracy of childhood obesity was moderate for predicting adult obesity, with a sensitivity of 30% and a specificity of 98%. Persistence of obesity from adolescence to adulthood was high. Thirty-four studies were included in the diagnostic accuracy review. Most of the studies used the least reliable reference standard (dual-energy X-ray absorptiometry); only 24% of studies were of high quality. The sensitivity of BMI for diagnosing obesity and overweight varied considerably; specificity was less variable. Pooled sensitivity of BMI was 74% (95% CI 64.2% to 81.8%) and pooled specificity was 95% (95% CI 92.2% to 96.4%). The acceptability to children and their carers of BMI or other common simple measures was generally good. Little evidence was available regarding childhood measures other than BMI. No individual-level analysis could be performed. Childhood BMI is not a good predictor of adult obesity or adult disease; the majority of obese adults were not obese as children and most obesity-related adult morbidity occurs in adults who had a healthy childhood weight. However, obesity (as measured using BMI) was found to persist from childhood to adulthood, with most obese adolescents also being obese in adulthood. BMI was found to be reasonably good for diagnosing obesity during childhood. There is no convincing evidence suggesting that any simple measure is better than BMI for diagnosing obesity in childhood or predicting adult obesity and morbidity. Further research on obesity measures other than BMI is needed to determine which is the best tool for diagnosing childhood obesity, and new cohort studies are needed to investigate the impact of contemporary childhood obesity on adult obesity and obesity-related morbidities. This study is registered as PROSPERO CRD42013005711. The National Institute for Health Research Health Technology Assessment programme.

Diminished heart rate reactivity to acute psychological stress is associated with enhanced carotid intima-media thickness through adverse health behaviors.

PubMed

Ginty, Annie T; Williams, Sarah E; Jones, Alexander; Roseboom, Tessa J; Phillips, Anna C; Painter, Rebecca C; Carroll, Douglas; de Rooij, Susanne R

2016-06-01

Recent evidence demonstrates that individuals with low heart rate (HR) reactions to acute psychological stress are more likely to be obese or smokers. Smoking and obesity are established risk factors for increased carotid intima-media thickness (IMT). The aim of this study was to examine the potential pathways linking intima-media thickness, smoking, body mass index (BMI), and HR stress reactivity. A total of 552 participants, 47.6% male, M (SD) age = 58.3 (0.94) years, were exposed to three psychological stress tasks (Stroop, mirror drawing, and speech) preceded by a resting baseline period; HR was recorded throughout. HR reactivity was calculated as the average response across the three tasks minus average baseline HR. Smoking status, BMI, and IMT were determined by trained personnel. Controlling for important covariates (e.g., socioeconomic status), structural equation modeling revealed that BMI and smoking mediated the negative relationship between HR reactivity and IMT. The hypothesized model demonstrated a good overall fit to the data, χ(2) (8) = 0.692, p = .403; CFI = 1.00; TLI = 1.00 SRMR = .01; RMSEA < .001 (90% CI < 0.01-0.11). HR reactivity was negatively related to BMI (β = -.16) and smoking (β = -.18), and these in turn were positively associated with IMT (BMI: β = .10; smoking: β = .17). Diminished HR stress reactivity appears to be a marker for enlarged IMT and appears to be exerting its impact through already established risks. Future research should examine this relationship longitudinally and aim to intervene early. © 2016 Society for Psychophysiological Research.

The Body and the Beautiful: Health, Attractiveness and Body Composition in Men’s and Women’s Bodies

PubMed Central

Brierley, Mary-Ellen; Brooks, Kevin R.; Mond, Jonathan; Stevenson, Richard J.

2016-01-01

The dominant evolutionary theory of physical attraction posits that attractiveness reflects physiological health, and attraction is a mechanism for identifying a healthy mate. Previous studies have found that perceptions of the healthiest body mass index (weight scaled for height; BMI) for women are close to healthy BMI guidelines, while the most attractive BMI is significantly lower, possibly pointing to an influence of sociocultural factors in determining attractive BMI. However, less is known about ideal body size for men. Further, research has not addressed the role of body fat and muscle, which have distinct relationships with health and are conflated in BMI, in determining perceived health and attractiveness. Here, we hypothesised that, if attractiveness reflects physiological health, the most attractive and healthy appearing body composition should be in line with physiologically healthy body composition. Thirty female and 33 male observers were instructed to manipulate 15 female and 15 male body images in terms of their fat and muscle to optimise perceived health and, separately, attractiveness. Observers were unaware that they were manipulating the muscle and fat content of bodies. The most attractive apparent fat mass for female bodies was significantly lower than the healthiest appearing fat mass (and was lower than the physiologically healthy range), with no significant difference for muscle mass. The optimal fat and muscle mass for men’s bodies was in line with the healthy range. Male observers preferred a significantly lower overall male body mass than did female observers. While the body fat and muscle associated with healthy and attractive appearance is broadly in line with physiologically healthy values, deviations from this pattern suggest that future research should examine a possible role for internalization of body ideals in influencing perceptions of attractive body composition, particularly in women. PMID:27257677

Perceived and Police-Reported Neighborhood Crime: Linkages to Adolescent Activity Behaviors and Weight Status.

PubMed

Forsyth, Ann; Wall, Melanie; Choo, Tse; Larson, Nicole; Van Riper, David; Neumark-Sztainer, Dianne

2015-08-01

Inadequate physical activity and obesity during adolescence are areas of public health concern. Questions exist about the role of neighborhoods in the etiology of these problems. This research addressed the relationships of perceived and objective reports of neighborhood crime to adolescent physical activity, screen media use, and body mass index (BMI). Socioeconomically and racially/ethnically diverse adolescents (N = 2,455, 53.4% female) from 20 urban, public middle and high schools in Minneapolis/St. Paul, Minnesota responded to a classroom survey in the Eating and Activity in Teens 2010 study. BMI was measured by research staff. Participants' mean age was 14.6 (standard deviation = 2.0); 82.7% represented racial/ethnic groups other than non-Hispanic white. Linear regressions examined associations between crime perceived by adolescents and crime reported to police and the outcomes of interest (BMI z-scores, physical activity, and screen time). Models were stratified by gender and adjusted for age, race/ethnicity, socioeconomic status, and school. BMI was positively associated with perceived crime among girls and boys and with reported crime in girls. For girls, there was an association between higher perceived crime and increased screen time; for boys, between higher reported property crime and reduced physical activity. Perceived crime was associated with reported crime, both property and personal, in both genders. Few prior studies of adolescents have studied the association between both perceived and reported crime and BMI. Community-based programs for youth should consider addressing adolescents' safety concerns along with other perceived barriers to physical activity. Interventions targeting actual crime rates are also important. Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

The Influence of Body Mass Index on Outcomes in Ureteroscopy: Results from the Clinical Research Office of Endourological Society URS Global Study.

PubMed

Krambeck, Amy; Wijnstok, Nienke; Olbert, Peter; Mitroi, George; Bariol, Simon; Shah, Hemendra N; El-Abd, Ahmed S; Onal, Bulent; de la Rosette, Jean

2017-01-01

Although ureteroscopy (URS) has been established as a viable treatment for stones in obese patients, its safety and success has not been fully elucidated. The current study describes the worldwide prevalence of obesity in patients with urolithiasis and examines trends in URS outcomes, safety, and efficacy. This study utilized the Clinical Research Office of the Endourological Society (CROES) URS Global Study, which was a prospective, multicenter study including 11,885 patients treated with URS for urinary stones at 1 of 114 urology departments across 32 countries. The relationship between body mass index (BMI), diabetes, and creatinine, with retreatment, stone-free rates, complications, and long hospital stay, was examined with a multivariate logistic regression analyses. Of the 10,099 URS patients with BMI data, 17.4% were obese and 2.2% were super obese. Overall, 86.7% patients were stone free and 16.8% required retreatment. Higher BMI was associated with lower stone-free rates, and any deviation from normal weight was associated with higher retreatment rates. In multivariate analysis controlling for several variables including stone size, the association between BMI and lower stone-free rates with higher retreatment rates persisted. Intraoperative complications occurred in 518 (5.1%) patients, and 343 (3.4%) experienced a postoperative complication. Postoperative complications were more frequent in the underweight and super obese subjects, and there was no relationship between BMI and intraoperative complications. Although URS for stone disease was found to be an overall safe procedure for obese and super obese patients, efficacy of the procedure may be lower compared with normal-weight subjects and higher retreatment rates may be necessary.

The accuracy of parent-reported height and weight for 6-12 year old U.S. children.

PubMed

Wright, Davene R; Glanz, Karen; Colburn, Trina; Robson, Shannon M; Saelens, Brian E

2018-02-12

Previous studies have examined correlations between BMI calculated using parent-reported and directly-measured child height and weight. The objective of this study was to validate correction factors for parent-reported child measurements. Concordance between parent-reported and investigator measured child height, weight, and BMI (kg/m 2 ) among participants in the Neighborhood Impact on Kids Study (n = 616) was examined using the Lin coefficient, where a value of ±1.0 indicates perfect concordance and a value of zero denotes non-concordance. A correction model for parent-reported height, weight, and BMI based on commonly collected demographic information was developed using 75% of the sample. This model was used to estimate corrected measures for the remaining 25% of the sample and measured concordance between correct parent-reported and investigator-measured values. Accuracy of corrected values in classifying children as overweight/obese was assessed by sensitivity and specificity. Concordance between parent-reported and measured height, weight and BMI was low (0.007, - 0.039, and - 0.005 respectively). Concordance in the corrected test samples improved to 0.752 for height, 0.616 for weight, and 0.227 for BMI. Sensitivity of corrected parent-reported measures for predicting overweight and obesity among children in the test sample decreased from 42.8 to 25.6% while specificity improved from 79.5 to 88.6%. Correction factors improved concordance for height and weight but did not improve the sensitivity of parent-reported measures for measuring child overweight and obesity. Future research should be conducted using larger and more nationally-representative samples that allow researchers to fully explore demographic variance in correction coefficients.

The mediating effects of dietary habits on the relationship between television viewing and body mass index among youth.

PubMed

Carson, Valerie; Janssen, Ian

2012-10-01

There is evidence to suggest that excessive television viewing is an independent determinant of obesity in young people. However, the pathways between television viewing and obesity are not fully understood. Therefore, the purpose of this study was to examine whether the relationship between television and body mass index (BMI) is mediated by television snacking and junk food consumption. Results are based on 15,973 youth in grades 6-10 who participated in the Canadian 2009/2010 health behaviour in school-aged children survey (HBSC). Participants self-reported their weight and height and BMI z-scores were calculated based on World Health Organization growth standards. Participants reported the frequency of snacking while watching television and the frequency of eating junk food (sweets, soft drinks, baked goods, French fries, potato chips). Total hours per week of television were calculated. A contemporary multiple mediation analysis was used to examine associations. A modest positive relationship was observed between television viewing and BMI. The mean BMI z-score was 0.15 units higher in youth in the highest television viewing quartile by comparison with the youth in the lowest quartile. However, contrary to our hypothesis, television snacking and junk food consumption were not significant positive mediators of the television and BMI relationship. The pathways between television viewing and obesity are complicated and remain poorly understood. Future research using longitudinal or experimental designs, more precise measurement tools and formal mediation analyses is needed. This research should consider mediators related to both energy intake and expenditure. © 2012 The Authors. Pediatric Obesity © 2012 International Association for the Study of Obesity.

The Body and the Beautiful: Health, Attractiveness and Body Composition in Men's and Women's Bodies.

PubMed

Brierley, Mary-Ellen; Brooks, Kevin R; Mond, Jonathan; Stevenson, Richard J; Stephen, Ian D

2016-01-01

The dominant evolutionary theory of physical attraction posits that attractiveness reflects physiological health, and attraction is a mechanism for identifying a healthy mate. Previous studies have found that perceptions of the healthiest body mass index (weight scaled for height; BMI) for women are close to healthy BMI guidelines, while the most attractive BMI is significantly lower, possibly pointing to an influence of sociocultural factors in determining attractive BMI. However, less is known about ideal body size for men. Further, research has not addressed the role of body fat and muscle, which have distinct relationships with health and are conflated in BMI, in determining perceived health and attractiveness. Here, we hypothesised that, if attractiveness reflects physiological health, the most attractive and healthy appearing body composition should be in line with physiologically healthy body composition. Thirty female and 33 male observers were instructed to manipulate 15 female and 15 male body images in terms of their fat and muscle to optimise perceived health and, separately, attractiveness. Observers were unaware that they were manipulating the muscle and fat content of bodies. The most attractive apparent fat mass for female bodies was significantly lower than the healthiest appearing fat mass (and was lower than the physiologically healthy range), with no significant difference for muscle mass. The optimal fat and muscle mass for men's bodies was in line with the healthy range. Male observers preferred a significantly lower overall male body mass than did female observers. While the body fat and muscle associated with healthy and attractive appearance is broadly in line with physiologically healthy values, deviations from this pattern suggest that future research should examine a possible role for internalization of body ideals in influencing perceptions of attractive body composition, particularly in women.

Towards a real-time interface between a biomimetic model of sensorimotor cortex and a robotic arm

PubMed Central

Dura-Bernal, Salvador; Chadderdon, George L; Neymotin, Samuel A; Francis, Joseph T; Lytton, William W

2015-01-01

Brain-machine interfaces can greatly improve the performance of prosthetics. Utilizing biomimetic neuronal modeling in brain machine interfaces (BMI) offers the possibility of providing naturalistic motor-control algorithms for control of a robotic limb. This will allow finer control of a robot, while also giving us new tools to better understand the brain’s use of electrical signals. However, the biomimetic approach presents challenges in integrating technologies across multiple hardware and software platforms, so that the different components can communicate in real-time. We present the first steps in an ongoing effort to integrate a biomimetic spiking neuronal model of motor learning with a robotic arm. The biomimetic model (BMM) was used to drive a simple kinematic two-joint virtual arm in a motor task requiring trial-and-error convergence on a single target. We utilized the output of this model in real time to drive mirroring motion of a Barrett Technology WAM robotic arm through a user datagram protocol (UDP) interface. The robotic arm sent back information on its joint positions, which was then used by a visualization tool on the remote computer to display a realistic 3D virtual model of the moving robotic arm in real time. This work paves the way towards a full closed-loop biomimetic brain-effector system that can be incorporated in a neural decoder for prosthetic control, to be used as a platform for developing biomimetic learning algorithms for controlling real-time devices. PMID:26709323

Multi-modal virtual environment research at Armstrong Laboratory

NASA Technical Reports Server (NTRS)

Eggleston, Robert G.

1995-01-01

One mission of the Paul M. Fitts Human Engineering Division of Armstrong Laboratory is to improve the user interface for complex systems through user-centered exploratory development and research activities. In support of this goal, many current projects attempt to advance and exploit user-interface concepts made possible by virtual reality (VR) technologies. Virtual environments may be used as a general purpose interface medium, an alternative display/control method, a data visualization and analysis tool, or a graphically based performance assessment tool. An overview is given of research projects within the division on prototype interface hardware/software development, integrated interface concept development, interface design and evaluation tool development, and user and mission performance evaluation tool development.

Self-healable interfaces based on thermo-reversible Diels-Alder reactions in carbon fiber reinforced composites.

PubMed

Zhang, W; Duchet, J; Gérard, J F

2014-09-15

Thermo-reversible Diels-Alder (DA) bonds formed between maleimide and furan groups have been used to generate an interphase between carbon fiber surface and an epoxy matrix leading to the ability of interfacial self-healing in carbon:epoxy composite materials. The maleimide groups were grafted on an untreated T700 carbon fiber from a three step surface treatment: (i) nitric acid oxidization, (ii) tetraethylenepentamine amination, and (iii) bismaleimide grafting. The furan groups were introduced in the reactive epoxy system from furfuryl glycidyl ether. The interface between untreated carbon fiber and epoxy matrix was considered as a reference. The interfacial shear strength (IFSS) was evaluated by single fiber micro-debonding test. The debonding force was shown to have a linear dependence with embedded length. The highest healing efficiency calculated from the debonding force was found to be about 82% more compared to the value for the reference interface. All the interphases designed with reversible DA bonds have a repeatable self-healing ability. As after the fourth healing, they can recover a relatively high healing efficiency (58% for the interphase formed by T700-BMI which is oxidized for 60 min during the first treatment step). Copyright © 2014 Elsevier Inc. All rights reserved.

Toward a Wireless Open Source Instrument: Functional Near-infrared Spectroscopy in Mobile Neuroergonomics and BCI Applications

PubMed Central

von Lühmann, Alexander; Herff, Christian; Heger, Dominic; Schultz, Tanja

2015-01-01

Brain-Computer Interfaces (BCIs) and neuroergonomics research have high requirements regarding robustness and mobility. Additionally, fast applicability and customization are desired. Functional Near-Infrared Spectroscopy (fNIRS) is an increasingly established technology with a potential to satisfy these conditions. EEG acquisition technology, currently one of the main modalities used for mobile brain activity assessment, is widely spread and open for access and thus easily customizable. fNIRS technology on the other hand has either to be bought as a predefined commercial solution or developed from scratch using published literature. To help reducing time and effort of future custom designs for research purposes, we present our approach toward an open source multichannel stand-alone fNIRS instrument for mobile NIRS-based neuroimaging, neuroergonomics and BCI/BMI applications. The instrument is low-cost, miniaturized, wireless and modular and openly documented on www.opennirs.org. It provides features such as scalable channel number, configurable regulated light intensities, programmable gain and lock-in amplification. In this paper, the system concept, hardware, software and mechanical implementation of the lightweight stand-alone instrument are presented and the evaluation and verification results of the instrument's hardware and physiological fNIRS functionality are described. Its capability to measure brain activity is demonstrated by qualitative signal assessments and a quantitative mental arithmetic based BCI study with 12 subjects. PMID:26617510

Basic research needs and opportunities on interfaces in solar materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Czanderna, A. W.; Gottschall, R. J.

1981-04-01

The workshop on research needs and recommended research programs on interfaces in solar energy conversion devices was held June 30-July 3, 1980. The papers deal mainly with solid-solid, solid-liquid, and solid-gas interfaces, sometimes involving multilayer solid-solid interfaces. They deal mainly with instrumental techniques of studying these interfaces so they can be optimized, so they can be fabricated with quality control and so changes with time can be forecast. The latter is required because a long lifetime (20 yrs is suggested) is necessary for economic reasons. Fifteen papers have been entered individually into EDB and ERA. (LTN)

A lower limb exoskeleton control system based on steady state visual evoked potentials.

PubMed

Kwak, No-Sang; Müller, Klaus-Robert; Lee, Seong-Whan

2015-10-01

We have developed an asynchronous brain-machine interface (BMI)-based lower limb exoskeleton control system based on steady-state visual evoked potentials (SSVEPs). By decoding electroencephalography signals in real-time, users are able to walk forward, turn right, turn left, sit, and stand while wearing the exoskeleton. SSVEP stimulation is implemented with a visual stimulation unit, consisting of five light emitting diodes fixed to the exoskeleton. A canonical correlation analysis (CCA) method for the extraction of frequency information associated with the SSVEP was used in combination with k-nearest neighbors. Overall, 11 healthy subjects participated in the experiment to evaluate performance. To achieve the best classification, CCA was first calibrated in an offline experiment. In the subsequent online experiment, our results exhibit accuracies of 91.3 ± 5.73%, a response time of 3.28 ± 1.82 s, an information transfer rate of 32.9 ± 9.13 bits/min, and a completion time of 1100 ± 154.92 s for the experimental parcour studied. The ability to achieve such high quality BMI control indicates that an SSVEP-based lower limb exoskeleton for gait assistance is becoming feasible.

RSRE: RNA structural robustness evaluator

PubMed Central

Shu, Wenjie; Zheng, Zhiqiang; Wang, Shengqi

2007-01-01

Biological robustness, defined as the ability to maintain stable functioning in the face of various perturbations, is an important and fundamental topic in current biology, and has become a focus of numerous studies in recent years. Although structural robustness has been explored in several types of RNA molecules, the origins of robustness are still controversial. Computational analysis results are needed to make up for the lack of evidence of robustness in natural biological systems. The RNA structural robustness evaluator (RSRE) web server presented here provides a freely available online tool to quantitatively evaluate the structural robustness of RNA based on the widely accepted definition of neutrality. Several classical structure comparison methods are employed; five randomization methods are implemented to generate control sequences; sub-optimal predicted structures can be optionally utilized to mitigate the uncertainty of secondary structure prediction. With a user-friendly interface, the web application is easy to use. Intuitive illustrations are provided along with the original computational results to facilitate analysis. The RSRE will be helpful in the wide exploration of RNA structural robustness and will catalyze our understanding of RNA evolution. The RSRE web server is freely available at http://biosrv1.bmi.ac.cn/RSRE/ or http://biotech.bmi.ac.cn/RSRE/. PMID:17567615

A lower limb exoskeleton control system based on steady state visual evoked potentials

NASA Astrophysics Data System (ADS)

Kwak, No-Sang; Müller, Klaus-Robert; Lee, Seong-Whan

2015-10-01

Objective. We have developed an asynchronous brain-machine interface (BMI)-based lower limb exoskeleton control system based on steady-state visual evoked potentials (SSVEPs). Approach. By decoding electroencephalography signals in real-time, users are able to walk forward, turn right, turn left, sit, and stand while wearing the exoskeleton. SSVEP stimulation is implemented with a visual stimulation unit, consisting of five light emitting diodes fixed to the exoskeleton. A canonical correlation analysis (CCA) method for the extraction of frequency information associated with the SSVEP was used in combination with k-nearest neighbors. Main results. Overall, 11 healthy subjects participated in the experiment to evaluate performance. To achieve the best classification, CCA was first calibrated in an offline experiment. In the subsequent online experiment, our results exhibit accuracies of 91.3 ± 5.73%, a response time of 3.28 ± 1.82 s, an information transfer rate of 32.9 ± 9.13 bits/min, and a completion time of 1100 ± 154.92 s for the experimental parcour studied. Significance. The ability to achieve such high quality BMI control indicates that an SSVEP-based lower limb exoskeleton for gait assistance is becoming feasible.

Null association between workplace social capital and body mass index. Results from a four-wave panel survey among employees in Japan (J-HOPE study).

PubMed

Tsuboya, Toru; Tsutsumi, Akizumi; Kawachi, Ichiro

2016-02-01

Research on the longitudinal association of workplace social capital and obesity is limited. We sought to investigate the prospective association of social capital in the workplace with body mass index (BMI) among employees in Japan. We used repeat panel surveys from 12 private companies in Japan. In the present study, four annual surveys waves were used, including 8811, 10,608, 9766, and 6249 participants, respectively. The first survey was conducted between October 2010 and December 2011 (response rate = 77.4%), and the following three surveys were conducted at approximately annual intervals. Questionnaires inquiring about workplace social capital, and other characteristics were administered at each survey. Height and weight were objectively measured in 11 companies, and self-reported in one company. Cross-sectional as well as fixed effects analysis of change in social capital and change in BMI were conducted. Analyses were stratified by age, sex, BMI at baseline, and companies. The analysis was conducted in 2015. Over 3 years, approximately 32% of the participants changed their BMI by more than 1 unit, while workplace social capital changed for approximately 78% of the sample. We found no associations between change in workplace social capital and change in BMI. The null association was preserved across analyses stratified by sex, age, overweight/obesity status at baseline, and company. Workplace social capital is not associated with changes in employee BMI. Copyright © 2015 Elsevier Ltd. All rights reserved.

The relationship between body mass index and uric acid: a study on Japanese adult twins.

PubMed

Tanaka, Kentaro; Ogata, Soshiro; Tanaka, Haruka; Omura, Kayoko; Honda, Chika; Hayakawa, Kazuo

2015-09-01

The present study aimed to investigate the association between body mass index (BMI) and uric acid (UA) using the twin study methodology to adjust for genetic factors. The association between BMI and UA was investigated in a cross-sectional study using data from both monozygotic and dizygotic twins registered at the Osaka University Center for Twin Research and the Osaka University Graduate School of Medicine. From January 2011 to March 2014, 422 individuals participated in the health examination. We measured height, weight, age, BMI, lifestyle habits (Breslow's Health Practice Index), serum UA, and serum creatinine. To investigate the association between UA and BMI with adjustment for the clustering of a twin within a pair, individual-level analyses were performed using generalized linear mixed models (GLMMs). To investigate an association with adjustment for genetic and family environmental factors, twin-pair difference values analyses were performed. In all analysis, BMI was associated with UA in men and women. Using the GLMMs, standardized regression coefficients were 0.194 (95 % confidence interval: 0.016-0.373) in men and 0.186 (95 % confidence interval: 0.071-0.302) in women. Considering twin-pair difference value analyses, standardized regression coefficients were 0.333 (95 % confidence interval: 0.072-0.594) in men and 0.314 (95 % confidence interval: 0.151-0.477) in women. The present study shows that BMI was significantly associated with UA, after adjusting for both genetic and familial environment factors in both men and women.

Overweight and obesity doubled over a 6-year period in young women living in poverty in Mexico.

PubMed

Neufeld, Lynnette M; Hernández-Cordero, Sonia; Fernald, Lia C; Ramakrishnan, Usha

2008-03-01

To document the changes in BMI and the prevalence of overweight and obesity in young women living in poverty in a semi-urban community in Mexico. Women who had previously participated in a longitudinal research study (1997-2000) were re-assessed in 2005. Anthropometric measurements were obtained using standard procedures, and socio-demographic questionnaires were administered. Total and annual rate of change in BMI and change in the prevalence of overweight and obesity (BMI > or = 25.0 and > or =30.0) were estimated. Mean age in 2005 was 30.0 +/- 5.7 years (n = 683) and time between recruitment and follow-up was 6.4 +/- 1.0 years. Mean change in BMI was +3.6 +/- 2.7 (range -8.2 to +14.6). In 2005, 500 (73.2%) women were overweight, up from 263 (38.5%) in the original assessment. The prevalence of obesity tripled over the follow-up period (from 9.8% to 30.3%). The mean annual rate of change in BMI was +0.6 (+/-0.4). After adjustment for age and parity at baseline, an annual rate of change of BMI above the sample median (>0.5) was associated with lower levels of formal education. The annual increase in the prevalence of overweight and obesity in this sample is double that which was reported at a national level in Mexico. An understanding of the determinants of this rapid increase among the women living in poverty in Mexico is urgently needed.

Polygenic risk predicts obesity in both white and black young adults.

PubMed

Domingue, Benjamin W; Belsky, Daniel W; Harris, Kathleen Mullan; Smolen, Andrew; McQueen, Matthew B; Boardman, Jason D

2014-01-01

To test transethnic replication of a genetic risk score for obesity in white and black young adults using a national sample with longitudinal data. A prospective longitudinal study using the National Longitudinal Study of Adolescent Health Sibling Pairs (n = 1,303). Obesity phenotypes were measured from anthropometric assessments when study members were aged 18-26 and again when they were 24-32. Genetic risk scores were computed based on published genome-wide association study discoveries for obesity. Analyses tested genetic associations with body-mass index (BMI), waist-height ratio, obesity, and change in BMI over time. White and black young adults with higher genetic risk scores had higher BMI and waist-height ratio and were more likely to be obese compared to lower genetic risk age-peers. Sibling analyses revealed that the genetic risk score was predictive of BMI net of risk factors shared by siblings. In white young adults only, higher genetic risk predicted increased risk of becoming obese during the study period. In black young adults, genetic risk scores constructed using loci identified in European and African American samples had similar predictive power. Cumulative information across the human genome can be used to characterize individual level risk for obesity. Measured genetic risk accounts for only a small amount of total variation in BMI among white and black young adults. Future research is needed to identify modifiable environmental exposures that amplify or mitigate genetic risk for elevated BMI.

Evaluation of the DSM-5 Severity Indicator for Anorexia Nervosa.

PubMed

Machado, Paulo P P; Grilo, Carlos M; Crosby, Ross D

2017-05-01

This study tested the new DSM-5 severity criterion for anorexia nervosa (AN) based on proposed body mass index (BMI) cut-points. Participants were a clinical sample of 201 treatment-seeking patients diagnosed with DSM-5 AN in Portugal. Participants were categorised based on DSM-5 severity levels and were compared on demographic and clinical variables assessed with the Eating Disorder Examination-Questionnaire. Based on DSM-5 severity definitions for AN, 73 (36.3%) participants were categorised as mild (≥17.0 BMI), 40 (19.9%) as moderate (16-16.99 BMI), 30 (14.9%) as severe (15-15.99 BMI) and 58 (28.9%) as extreme (<15 BMI). The severity groups did not differ significantly in age or gender. Analyses comparing the severity groups on measures of eating-disorder psychopathology revealed no significant differences on the Eating Disorder Examination-Questionnaire global or subscale scores. The groups also did not differ significantly on the frequency of binge eating or purging episodes within the past 28 days. Our findings, in this clinical sample of patients with AN in Portugal, provide no evidence for the new DSM-5 severity ratings based on BMI level. Further research on the validity of the DSM-5 specifiers is needed and should test additional clinical or functional variables and especially prognostic utility for course and outcome across eating disorders. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association.

Does food vendor density mediate the association between neighborhood deprivation and BMI?: a G-computation mediation analysis.

PubMed

Zhang, Y Tara; Laraia, Barbara A; Mujahid, Mahasin S; Tamayo, Aracely; Blanchard, Samuel D; Warton, E Margaret; Kelly, N Maggi; Moffet, Howard H; Schillinger, Dean; Adler, Nancy; Karter, Andrew J

2015-05-01

In previous research, neighborhood deprivation was positively associated with body mass index (BMI) among adults with diabetes. We assessed whether the association between neighborhood deprivation and BMI is attributable, in part, to geographic variation in the availability of healthful and unhealthful food vendors. Subjects were 16,634 participants of the Diabetes Study of Northern California, a multiethnic cohort of adults living with diabetes. Neighborhood deprivation and healthful (supermarket and produce) and unhealthful (fast food outlets and convenience stores) food vendor kernel density were calculated at each participant's residential block centroid. We estimated the total effect, controlled direct effect, natural direct effect, and natural indirect effect of neighborhood deprivation on BMI. Mediation effects were estimated using G-computation, a maximum likelihood substitution estimator of the G-formula that allows for complex data relations such as multiple mediators and sequential causal pathways. We estimated that if neighborhood deprivation was reduced from the most deprived to the least deprived quartile, average BMI would change by -0.73 units (95% confidence interval: -1.05, -0.32); however, we did not detect evidence of mediation by food vendor density. In contrast to previous findings, a simulated reduction in neighborhood deprivation from the most deprived to the least deprived quartile was associated with dramatic declines in both healthful and unhealthful food vendor density. Availability of food vendors, both healthful and unhealthful, did not appear to explain the association between neighborhood deprivation and BMI in this population of adults with diabetes.

Saturated fat intake modulates the association between a genetic risk score of obesity and BMI in two US populations

PubMed Central

Casas-Agustench, Patricia; Arnett, Donna K.; Smith, Caren E.; Lai, Chao-Qiang; Parnell, Laurence D.; Borecki, Ingrid B.; Frazier-Wood, Alexis C.; Allison, Matthew; Chen, Yii-Der Ida; Taylor, Kent D.; Rich, Stephen S.; Rotter, Jerome I.; Lee, Yu-Chi; Ordovás, José M.

2014-01-01

Combining multiple genetic variants related to obesity into a genetic risk score (GRS) might improve identification of individuals at risk of developing obesity. Moreover, characterizing gene-diet interactions is a research challenge to establish dietary recommendations to individuals with higher predisposition to obesity. Our objective was to analyze the association between an obesity GRS and BMI in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) population, focusing on gene-diet interactions with total fat and saturated fatty acid (SFA) intake and to replicate findings in Multi-Ethnic Study of Atherosclerosis (MESA) population. Cross-sectional analyses included 783 US Caucasian participants from GOLDN and 2035 from MESA. Dietary intakes were estimated with validated food frequency questionnaires. Height and weight were measured. A weighted GRS was calculated on the basis of 63 obesity-associated variants. Multiple linear regression models adjusted by potential confounders were used to examine gene-diet interactions between dietary intake (total fat and SFA) and the obesity GRS in determining BMI. Significant interactions were found between total fat intake and the obesity GRS using these variables as continuous for BMI (P for interaction=0.010, 0.046, and 0.002 in GOLDN, MESA and meta-analysis, respectively). These association terms were stronger when assessing interactions between SFA intake and GRS for BMI (P for interaction=0.005, 0.018, and <0.001 in GOLDN, MESA and meta-analysis, respectively). SFA intake interacts with an obesity GRS in modulating BMI in two US populations. Although to determine the causal direction requires further investigation, these findings suggest that potential dietary recommendations to reduce BMI effectively in populations with high obesity GRS would be to reduce total fat intake mainly by limiting SFAs. PMID:24794412

Changes in Body Mass Index During a 3-Year Elementary School-Based Obesity Prevention Program for American Indian and White Rural Students.

PubMed

Vogeltanz-Holm, Nancy; Holm, Jeffrey

2018-04-01

Childhood obesity is a significant but largely modifiable health risk, disproportionately affecting socioeconomically disadvantaged, racial/ethnic minority, and rural children. Elementary school-aged children typically experience the greatest increases in excess weight gain and therefore are important targets for reducing adolescent and adult obesity while improving children's health. Our study evaluated outcomes of a 3-year elementary school-based program for reducing obesity in American Indian and White students attending eight rural schools in the U.S. upper Midwest. Researchers measured body mass indexes (BMI) and other health indicators and behaviors of 308 beginning third-grade students and then again at the end of students' third, fourth, and fifth grades. The primary focus of this study is a mixed multilevel longitudinal model testing changes in age- and gender-adjusted BMI z scores ( zBMI). There was a significant decrease in zBMI across the 3-year study period. Ethnicity analyses showed that White students had overall decreases in zBMI whereas American Indian students' zBMIs remained stable across the program. Comparisons with children from an age- and cohort-matched national sample provided support for the effectiveness of the school program in reducing BMI and obesity during the study period. An elementary school-based health program that addresses a range of students' obesity-related health behaviors, the school health environment, and that involves educators and parents is an effective intervention for reducing or stabilizing BMI in rural White and American Indian students. School health programs for students living in rural communities may be especially effective due to greater school and community cohesiveness, and valuing of the school's primary role in improving community health.

The Cross-Sectional Relationship Between Body Mass Index, Waist-Hip Ratio and Cognitive Performance in Postmenopausal Women Enrolled in the Women's Health Initiative (WHI)

PubMed Central

Kerwin, Diana R.; Zhang, Yinghua; Kotchen, Jane Morley; Espeland, Mark A.; Van Horn, Linda; McTigue, Kathleen M.; Robinson, Jennifer G.; Powell, Lynda; Kooperberg, Charles; Coker, Laura H.; Hoffmann, Raymond

2010-01-01

OBJECTIVES To determine if body weight (BMI) is independently associated with cognitive function in postmenopausal women and the relationship between body fat distribution as estimated by waist-hip-ratio (WHR) and cognitive function. DESIGN Cross-sectional data analysis SETTING Baseline data from the Women's Health Initiative (WHI) hormone trials. PARTICIPANTS 8745 postmenopausal women aged 65–79 years, free of clinical evidence of dementia and completed baseline evaluation in the Women's Health Initiative (WHI) hormone trials. MEASUREMENTS Participants completed a Modified Mini-Mental State Examination (3MSE), health and lifestyle questionnaires, and standardized measurements of height, weight, body circumferences and blood pressure. Statistical analysis of associations between 3MSE scores, BMI and WHR after controlling for known confounders. RESULTS With the exception of smoking and exercise, vascular disease risk factors, including hypertension, waist measurement, heart disease and diabetes, were significantly associated with 3MSE score and were included as co-variables in subsequent analyses. BMI was inversely related to 3MSE scores, for every 1 unit increase in BMI, 3MSE decrease 0.988 (p=.0001) after adjusting for age, education and vascular disease risk factors. BMI had the most pronounced association with poorer cognitive functioning scores among women with smaller waist measurements. Among women with the highest WHR, cognitive scores increased with BMI. CONCLUSION Increasing BMI is associated with poorer cognitive function in women with smaller WHR. Higher WHR, estimating central fat mass, is associated with higher cognitive function in this cross-sectional study. Further research is needed to clarify the mechanism for this association. PMID:20646100

The cross-sectional relationship between body mass index, waist-hip ratio, and cognitive performance in postmenopausal women enrolled in the Women's Health Initiative.

PubMed

Kerwin, Diana R; Zhang, Yinghua; Kotchen, Jane Morley; Espeland, Mark A; Van Horn, Linda; McTigue, Kathleen M; Robinson, Jennifer G; Powell, Lynda; Kooperberg, Charles; Coker, Laura H; Hoffmann, Raymond

2010-08-01

To determine whether body mass index (BMI) is independently associated with cognitive function in postmenopausal women and the relationship between body fat distribution as estimated by waist-hip ratio (WHR). Cross-sectional data analysis. Baseline data from the Women's Health Initiative (WHI) hormone trials. Eight thousand seven hundred forty-five postmenopausal women aged 65 to 79 free of clinical evidence of dementia who completed the baseline evaluation in the WHI hormone trials. Participants completed a Modified Mini-Mental State Examination (3MSE), health and lifestyle questionnaires, and standardized measurements of height, weight, body circumference, and blood pressure. Statistical analysis was performed of associations between 3MSE score, BMI, and WHR after controlling for known confounders. With the exception of smoking and exercise, vascular disease risk factors, including hypertension, waist measurement, heart disease, and diabetes mellitus, were significantly associated with 3MSE score and were included as covariables in subsequent analyses. BMI was inversely related to 3MSE score; for every 1-unit increase in BMI, 3MSE score decreased 0.988 points (P<.001) after adjusting for age, education, and vascular disease risk factors. BMI had the most pronounced association with poorer cognitive functioning scores in women with smaller waist measurements. In women with the highest WHR, cognitive scores increased with BMI. Higher BMI was associated with poorer cognitive function in women with smaller WHR. Higher WHR, estimating central fat mass, was associated with higher cognitive function in this cross-sectional study. Further research is needed to clarify the mechanism for this association. © 2010, Copyright the Authors. Journal compilation © 2010, No claim to original US government works.

Poor outcomes and satisfaction in adolescent idiopathic scoliosis surgery: the relevance of the body mass index and self-image.

PubMed

Pérez-Prieto, Daniel; Sánchez-Soler, Juan Francisco; Martínez-Llorens, Juana; Mojal, Sergi; Bagó, Joan; Cáceres, Enric; Ramírez, Manuel

2015-02-01

The purpose of this study was to evaluate patients with adolescent idiopathic scoliosis (AIS) to determine whether a low body mass index (BMI) influences surgery outcomes and satisfaction. There were 39 patients in this prospective 3-year cohort study. The BMI, Cobb angle, the Body Shape Questionnaire 14 (BSQ-14), the Scoliosis Research Society Questionnaire 22 (SRS-22) and eight satisfaction questions results were obtained. Having a BMI greater than or less than 18 kg/m(2) was used as a determiner to allocate patients to groups. As a low BMI is related to the presence of a disturbance in body perception, patients were also dichotomized by using the BSQ-14. All scales were worse in both slimmer patients and the group with a body perception disorder. The group with a BMI <18 kg/m(2) obtained a total of 82.31 points in the SRS-22, and it was 93.45 points for the group with a BMI >18 kg/m(2) (p = 0.001). In terms of satisfaction, the percentage of patients that would undergo surgery again was 30.8 vs 69.2 % (p = 0.054). Patients with an alteration of physical perception obtained a total SRS-22 of 82.90 points versus 96.10 points in the control group (p < 0.001). No differences in terms of the Cobb correction (p = 0.29) or the percentage of correction (p = 0.841) were found in any case. The alteration of physical perception and a low BMI negatively affect the outcomes in AIS surgery, regardless of the curve magnitude and the percentage of correction. Considerable care should be taken in recommending surgical correction to these patients.

Associations of body mass index and waist circumference with: energy intake and percentage energy from macronutrients, in a cohort of australian children

PubMed Central

2011-01-01

Background It is evident from previous research that the role of dietary composition in relation to the development of childhood obesity remains inconclusive. Several studies investigating the relationship between body mass index (BMI), waist circumference (WC) and/or skin fold measurements with energy intake have suggested that the macronutrient composition of the diet (protein, carbohydrate, fat) may play an important contributing role to obesity in childhood as it does in adults. This study investigated the possible relationship between BMI and WC with energy intake and percentage energy intake from macronutrients in Australian children and adolescents. Methods Height, weight and WC measurements, along with 24 h food and drink records (FDR) intake data were collected from 2460 boys and girls aged 5-17 years living in the state of Queensland, Australia. Results Statistically significant, yet weak correlations between BMI z-score and WC with total energy intake were observed in grades 1, 5 and 10, with only 55% of subjects having a physiologically plausible 24 hr FDR. Using Pearson correlations to examine the relationship between BMI and WC with energy intake and percentage macronutrient intake, no significant correlations were observed between BMI z-score or WC and percentage energy intake from protein, carbohydrate or fat. One way ANOVAs showed that although those with a higher BMI z-score or WC consumed significantly more energy than their lean counterparts. Conclusion No evidence of an association between percentage macronutrient intake and BMI or WC was found. Evidently, more robust longitudinal studies are needed to elucidate the relationship linking obesity and dietary intake. PMID:21615883

Adolescent adrenocortical activity and adiposity: differences by sex and exposure to early maternal depression.

PubMed

Ruttle, Paula L; Klein, Marjorie H; Slattery, Marcia J; Kalin, Ned H; Armstrong, Jeffrey M; Essex, Marilyn J

2014-09-01

Prior research has linked either basal cortisol levels or stress-induced cortisol responses to adiposity; however, it remains to be determined whether these distinct cortisol measures exert joint or independent effects. Further, it is unclear how they interact with individual and environmental characteristics to predict adiposity. The present study aims to address whether morning cortisol levels and cortisol responses to a psychosocial stressor independently and/or interactively influence body mass index (BMI) in 218 adolescents (117 female) participating in a longitudinal community study, and whether associations are moderated by sex and exposure to early maternal depression. Reports of maternal depressive symptoms were obtained in infancy and preschool. Salivary cortisol measures included a longitudinal morning cortisol measure comprising sampling points across ages 11, 13, 15, and 18 and measures of stress-induced cortisol responses assessed via the Trier Social Stress Test (TSST) at age 18. Lower morning cortisol and higher TSST cortisol reactivity independently predicted higher age 18 BMI. Morning cortisol also interacted with sex and exposure to early maternal depression to predict BMI. Specifically, girls exposed to lower levels of early maternal depression displayed a strong negative morning cortisol-BMI association, and girls exposed to higher levels of maternal depression demonstrated a weaker negative association. Among boys, those exposed to lower levels of maternal depression displayed no association, while those exposed to higher levels of maternal depression displayed a negative morning cortisol-BMI association. Results point to the independent, additive effects of morning and reactive cortisol in the prediction of BMI and suggest that exposure to early maternal depression may exert sexually dimorphic effects on normative cortisol-BMI associations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Body Adiposity Index Utilization in a Spanish Mediterranean Population: Comparison with the Body Mass Index

PubMed Central

López, Angel A.; Cespedes, Mey L.; Vicente, Teofila; Tomas, Matias; Bennasar-Veny, Miguel; Tauler, Pedro; Aguilo, Antoni

2012-01-01

Background Body fat content and fat distribution or adiposity are indicators of health risk. Several techniques have been developed and used for assessing and/or determining body fat or adiposity. Recently, the Body Adiposity Index (BAI), which is based on the measurements of hip circumference and height, has been suggested as a new index of adiposity. The aim of the study was to compare BAI and BMI measurements in a Caucasian population from a European Mediterranean area and to assess the usefulness of the BAI in men and women separately. Research Methodology/Principal Findings A descriptive cross-sectional study was conducted in a Caucasian population. All participants in the study (1,726 women and 1,474 men, mean age 39.2 years, SD 10.8) were from Mallorca (Spain). Anthropometric data, including percentage of body fat mass obtained by Bioelectrical Impedance Analysis, were determined. Body Mass Index (BMI) and BAI were calculated. BAI and BMI showed a good correlation (r = 0.64, p<0.001). A strong correlation was also found between BAI and the % fat determined using BIA (r = 0.74, p<0.001), which is even stronger than the one between BMI and % fat (r = 0.54, p<0.001). However, the ROC curve analysis showed a higher accuracy for BMI than for the BAI regarding the discriminatory capacity. Conclusion The BAI could be a good tool to measure adiposity due, at least in part, to the advantages over other more complex mechanical or electrical systems. Probably, the most important advantage of BAI over BMI is that weight is not needed. However, in general it seems that the BAI does not overcome the limitations of BMI. PMID:22496915

Different measures of body weight as predictors of sickness absence.

PubMed

Korpela, Katri; Roos, Eira; Lallukka, Tea; Rahkonen, Ossi; Lahelma, Eero; Laaksonen, Mikko

2013-02-01

Excessive weight is associated with increased sickness absence from work due to obesity-linked health problems. However, it is not known which obesity measure best predicts sickness absence. First, we aimed to compare body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) as predictors of sickness absence spells of various lengths. Second, we aimed to compare BMI based on self-reported and measured weight and height as a predictor of sickness absence to assess the validity of self-reported BMI. The participants were 5750 employees of the City of Helsinki, aged 40-60 years, who were followed up on average for 4.8 years using the employer's register. Sickness absence spells were classified as self-certified short (1-3 days), medically certified medium length (4-14 days), and long (>14 days) absence spells. All measures of body weight predicted sickness absence. The relative rates of long sickness absence in the highest quintile as compared to the lowest quintile varied in women from 1.62 (95% CI 1.35-1.94) to 1.89 (95% CI 1.62-2.23) and in men from 1.40 (95% CI 0.76-2.59) to 2.33 (95% CI 1.32-4.11). Differences in the predictive power of BMI and WC were small: both were more strongly associated with sickness absence than WHR. Self-reported BMI performed equally well as measured BMI. BMI - measured or self-reported - is a valid anthropometric indicator of body weight and predictor of obesity-associated health-risks. Its use is feasible for research purposes as well as for the assessment of weight-related risks to work ability.

Food Security and Weight Status in Children: Interactions With Food Assistance Programs.

PubMed

Nguyen, Binh T; Ford, Christopher N; Yaroch, Amy L; Shuval, Kerem; Drope, Jeffrey

2017-02-01

It is unclear whether Supplemental Nutrition Assistance Program (SNAP) or National School Lunch Program (NSLP) participation modifies the relationship between food insecurity and obesity in children. Data were included for 4,719 children aged 9-17 years who participated in the National Health and Nutrition Survey between 2003-2004 and 2011-2012. Linear regression was used to examine the relationship between household food security (full, marginal, low, and very low) and BMI percentile. Adjusted models were also stratified by SNAP and NSLP participation. There was no significant overall relationship between household food security and BMI percentile. In SNAP non-participants, there was no apparent overall relationship between BMI percentile and household food security. However, BMI percentile in children from households with low food security was significantly higher than that of children from fully food-secure households (risk difference [RD]=5.95, 95% CI=1.11, 10.80). Among SNAP participants, there was no significant relationship between household food security and BMI percentile. By NSLP participation category, there was a non-significant trend toward increasing BMI percentile with decreasing household food security in those reporting two or fewer (RD=1.75, 95% CI= -0.79, 4.29) and two to three (RD=1.07; 95% CI= -1.74, 3.89) lunches/week. There was no apparent relationship between household food security and BMI percentile in those reporting four or more lunches/week. Although the overall relationship between household food security and weight status in school-aged children was not statistically significant, there was some evidence that the relationship may differ by SNAP or NSLP participation, suggesting the need for more research. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Prenatal organochlorine compound exposure, rapid weight gain, and overweight in infancy.

PubMed

Mendez, Michelle A; Garcia-Esteban, Raquel; Guxens, Mónica; Vrijheid, Martine; Kogevinas, Manolis; Goñi, Fernando; Fochs, Silvia; Sunyer, Jordi

2011-02-01

Although it has been hypothesized that fetal exposure to endocrine-disrupting chemicals may increase obesity risk, empirical data are limited, and it is uncertain how early in life any effects may begin. We explored whether prenatal exposure to several organochlorine compounds (OCs) is associated with rapid growth in the first 6 months of life and body mass index (BMI) later in infancy. Data come from the INMA (Infancia y Medio-Ambiente) Child and Environment birth cohort in Spain, which recruited 657 women in early pregnancy. Rapid growth during the first 6 months was defined as a change in weight-for-age z-scores > 0.67, and elevated BMI at 14 months, as a z-score ≥ the 85th percentile. Generalized linear models were used to estimate the risk of rapid growth or elevated BMI associated with 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE), hexachlorobenzene, β-hexachlorohexane, and polychlorinated biphenyls in first-trimester maternal serum. After multivariable adjustment including other OCs, DDE exposure above the first quartile was associated with doubling of the risk of rapid growth among children of normal-weight (BMI < 25 kg/m2), but not overweight, mothers. DDE was also associated with elevated BMI at 14 months (relative risk per unit increase in log DDE = 1.50; 95% confidence interval, 1.11-2.03). Other OCs were not associated with rapid growth or elevated BMI after adjustment. In this study we found prenatal DDE exposure to be associated with rapid weight gain in the first 6 months and elevated BMI later in infancy, among infants of normal-weight mothers. More research exploring the potential role of chemical exposures in early-onset obesity is needed.

Psychosocial outcomes in a weight loss camp for overweight youth

PubMed Central

QUINLAN, NICOLE P.; KOLOTKIN, RONETTE L.; FUEMMELER, BERNARD F.; COSTANZO, PHILIP R.

2015-01-01

Objective There is good evidence that youth attending weight loss camps in the UK and US are successful at achieving weight loss. Limited research suggests improvement in body image and self-esteem as well. This study evaluated changes in eight psychosocial variables following participation in a weight loss camp and examined the role of gender, age, length of stay, and body mass index (BMI) in these changes. Methods This was an observational and self-report study of 130 participants (mean age=12.8; mean BMI=33.5; 70% female; 77% Caucasian). The program consisted of an 1 800 kcal/day diet, daily supervised physical activities, cooking/nutrition classes, and weekly psycho-educational/support groups led by psychology staff. Participants completed measures of anti-fat attitudes, values (e.g., value placed on appearance, athletic ability, popularity), body- and self-esteem, weight- and health-related quality of life, self-efficacy, and depressive symptoms. Results Participants experienced significant BMI reduction (average decrease of 7.5 kg [standard deviation, SD=4.2] and 2.9 BMI points [SD=1.4]). Participants also exhibited significant improvements in body esteem, self-esteem, self-efficacy, generic and weight-related quality of life, anti-fat attitudes, and the importance placed on appearance. Changes in self-efficacy, physical functioning and social functioning remained significant even after adjusting for initial zBMI, BMI change, and length of stay. Gender differences were found on changes in self-efficacy, depressive symptoms, and social functioning. Conclusion Participation in weight loss programs in a group setting, such as a camp, may have added benefit beyond BMI reduction. Greater attention to changes in psychosocial variables may be warranted when designing such programs for youth. PMID:19107660

Associations between major chain fast-food outlet availability and change in body mass index: a longitudinal observational study of women from Victoria, Australia.

PubMed

Lamb, Karen E; Thornton, Lukar E; Olstad, Dana Lee; Cerin, Ester; Ball, Kylie

2017-10-16

The residential neighbourhood fast-food environment has the potential to lead to increased levels of obesity by providing opportunities for residents to consume energy-dense products. This longitudinal study aimed to examine whether change in body mass index (BMI) differed dependent on major chain fast-food outlet availability among women residing in disadvantaged neighbourhoods. Eighty disadvantaged neighbourhoods in Victoria, Australia. Sample of 882 women aged 18-46 years at baseline (wave I: 2007/2008) who remained at the same residential location at all three waves (wave II: 2010/2011; wave III: 2012/2013) of the Resilience for Eating and Activity Despite Inequality study. BMI based on self-reported height and weight at each wave. There was no evidence of an interaction between time and the number of major chain fast-food outlets within 2 (p=0.88), 3 (p=0.66) or 5 km (p=0.24) in the multilevel models of BMI. Furthermore, there was no evidence of an interaction between time and change in availability at any distance and BMI. Change in BMI was not found to differ by residential major chain fast-food outlet availability among Victorian women residing in disadvantaged neighbourhoods. It may be that exposure to fast-food outlets around other locations regularly visited influence change in BMI. Future research needs to consider what environments are the key sources for accessing and consuming fast food and how these relate to BMI and obesity risk. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Adherence to the World Cancer Research Fund/American Institute for Cancer Research cancer prevention recommendations and breast cancer risk in the Cancer de Màma (CAMA) study.

PubMed

Fanidi, Anouar; Ferrari, Pietro; Biessy, Carine; Ortega, Carolina; Angeles-Llerenas, Angélica; Torres-Mejia, Gabriella; Romieu, Isabelle

2015-12-01

We investigated the association between adherence to the recommendations of the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) and breast cancer (BC) risk in the Cancer de Màma (CAMA) study in a Mexican population. Population-based case-control study. Incident BC cases (n 1000) and controls (n 1074) matched on age, region and health-care system were recruited. In-person interviews were conducted to assess BC risk factors and habitual diet was assessed with an FFQ. Conformity to the WCRF/AICR recommendations was evaluated through a score incorporating seven WCRF/AICR components (body fatness, physical activity, foods and drinks that promote weight gain, plant foods, animal foods, alcoholic drinks and breast-feeding), with high scores indicating adherence to the WCRF/AICR recommendations. No statistically significant associations between WCRF/AICR score and risk of BC were observed. After excluding BMI from the WCRF/AICR score, the top quartile was associated with a decreased BC risk overall, with ORQ4-Q1=0.68 (95% CI 0.49, 0.92, P trend=0.03), and among postmenopausal women, with ORQ4-Q1=0.60 (95% CI 0.39, 0.94, P trend=0.03). Inverse associations were observed between BMI and risk of BC overall and among premenopausal women, with OR=0.57 (95% CI 0.42, 0.76, P trend <0.01) and 0.48 (95% CI 0.31, 0.73, P trend<0.01), respectively. Physical activity level was inversely associated with BC risk. The WCRF/AICR index was not related with BC risk in the CAMA study. A combination of six components excluding BMI showed strong protective associations, particularly in postmenopausal women. Further prospective studies are required to clarify the role of adherence to WCRF/AICR recommendations, particularly with respect to BMI, in the Mexican population.

The impact of weight misperception on health-related quality of life in Korean adults (KNHANES 2007–2014): a community-based cross-sectional study

PubMed Central

Park, Susan; Lee, Sejin; Hwang, Jinseub; Kwon, Jin-Won

2017-01-01

Background/objectives Weight perception, especially misperception, might affect health-related quality of life (HRQoL); however, related research is scarce and results remain equivocal. We examined the association between HRQoL and weight misperception by comparing obesity level as measured by body mass index (BMI) and weight perception in Korean adults. Methods Study subjects were 43 883 adults aged 19 years or older from cycles IV (2007–2009), V (2010–2012) and VI (2013–2014) of the Korean National Health and Nutrition Examination Survey. Multiple regression analyses comprising both logit and tobit models were conducted to evaluate the independent effect of obesity level as measured by BMI, weight perception and weight misperception on HRQoL after adjusting for demographics, socioeconomic status and number of chronic diseases. We also performed multiple regressions to explore the association between weight misperception and HRQoL stratified by BMI status. Results Obesity level as measured by BMI and weight perception were independently associated with low HRQoL in both separate and combined analyses. Weight misperception, including underestimation and overestimation, had a significantly negative impact on HRQoL. In subgroup analysis, subjects with BMI ranges from normal to overweight who misperceived their weight also had a high risk of low HRQoL. Overestimation of weight among obese subjects associated with low HRQoL, whereas underestimation of weight showed no significant association. Conclusions Both obesity level as measured by BMI and perceiving weight as fat were significant risk factors for low HRQoL. Subjects who incorrectly perceived their weight relative to their BMI status were more likely to report impaired HRQoL, particularly subjects with BMI in the normal to overweight range. Based on these findings, we recommend political and clinical efforts to better inform individuals about healthy weight status and promote accurate weight perception. PMID:28645975

BMI and risk of dementia in two million people over two decades: a retrospective cohort study.

PubMed

Qizilbash, Nawab; Gregson, John; Johnson, Michelle E; Pearce, Neil; Douglas, Ian; Wing, Kevin; Evans, Stephen J W; Pocock, Stuart J

2015-06-01

Dementia and obesity are increasingly important public health issues. Obesity in middle age has been proposed to lead to dementia in old age. We investigated the association between BMI and risk of dementia. For this retrospective cohort study, we used a cohort of 1,958,191 individuals derived from the United Kingdom Clinical Practice Research Datalink (CPRD) which included people aged 40 years or older in whom BMI was recorded between 1992 and 2007. Follow-up was until the practice's final data collection date, patient death or transfer out of practice, or first record of dementia (whichever occurred first). People with a previous record of dementia were excluded. We used Poisson regression to calculate incidence rates of dementia for each BMI category. Our cohort of 1,958,191 people from UK general practices had a median age at baseline of 55 years (IQR 45-66) and a median follow-up of 9·1 years (IQR 6·3-12·6). Dementia occurred in 45,507 people, at a rate of 2·4 cases per 1000 person-years. Compared with people of a healthy weight, underweight people (BMI <20 kg/m(2)) had a 34% higher (95% CI 29-38) risk of dementia. Furthermore, the incidence of dementia continued to fall for every increasing BMI category, with very obese people (BMI >40 kg/m(2)) having a 29% lower (95% CI 22-36) dementia risk than people of a healthy weight. These patterns persisted throughout two decades of follow-up, after adjustment for potential confounders and allowance for the J-shape association of BMI with mortality. Being underweight in middle age and old age carries an increased risk of dementia over two decades. Our results contradict the hypothesis that obesity in middle age could increase the risk of dementia in old age. The reasons for and public health consequences of these findings need further investigation. None. Copyright © 2015 Elsevier Ltd. All rights reserved.

Impact of primary care exercise referral schemes on the health of patients with obesity

PubMed Central

Parretti, Helen M; Bartington, Suzanne E; Badcock, Tim; Hughes, Lucy; Duda, Joan L; Jolly, Kate

2017-01-01

Primary care exercise referral schemes (ERSs) are a potentially useful setting to promote physical activity (PA). It is not established, however, whether interventions to increase PA, such as ERSs, have differing health outcomes according to the participants’ body mass index (BMI). This paper summarizes evidence for the impact of primary care ERSs on the health of people with obesity and reports findings of a reanalysis of the EMPOWER study, providing the first data to report differential outcomes of ERSs by BMI category. Our literature review revealed a paucity of published data. A 2011 Health Technology Assessment review and 2015 update were identified, but normal-weight participants were neither excluded nor were results stratified by weight in the included studies. A study of the effect of exercise referral in overweight women reported a significantly greater increase in PA levels in the ERS group than the control group at 3 months. Reanalysis of the EMPOWER study data showed a significant improvement in PA at 3 months in both obese and overweight/normal BMI groups, with the effect size attenuated to 6 months. There was no significant difference from baseline to 6 months in blood pressure for either BMI category. At 6 months, there was a significant decrease in weight from baseline for the obese category. Comparison of crude mean differences between BMI groups revealed a significant mean difference in PA at 3 months favoring the overweight/normal BMI group, but not at 6 months. There were no further significant differences in unadjusted or adjusted mean differences for other outcomes at follow-up. We report some evidence of a differential impact of ERS on PA by BMI category. However, the effect of ERSs in primary care for patients with obesity remains unclear due to the small number of published studies that have reported outcomes by BMI category. Further research is needed. PMID:29033627

Rising Obesity Prevalence and Weight Gain Among Adults Starting Antiretroviral Therapy in the United States and Canada

PubMed Central

Jenkins, Cathy A.; Lau, Bryan; Shepherd, Bryan E.; Justice, Amy C.; Tate, Janet P.; Buchacz, Kate; Napravnik, Sonia; Mayor, Angel M.; Horberg, Michael A.; Blashill, Aaron J.; Willig, Amanda; Wester, C. William; Silverberg, Michael J.; Gill, John; Thorne, Jennifer E.; Klein, Marina; Eron, Joseph J.; Kitahata, Mari M.; Sterling, Timothy R.; Moore, Richard D.

2016-01-01

Abstract The proportion of overweight and obese adults in the United States and Canada has increased over the past decade, but temporal trends in body mass index (BMI) and weight gain on antiretroviral therapy (ART) among HIV-infected adults have not been well characterized. We conducted a cohort study comparing HIV-infected adults in the North America AIDS Cohort Collaboration on Research and Design (NA-ACCORD) to United States National Health and Nutrition Examination Survey (NHANES) controls matched by sex, race, and age over the period 1998 to 2010. Multivariable linear regression assessed the relationship between BMI and year of ART initiation, adjusting for sex, race, age, and baseline CD4+ count. Temporal trends in weight on ART were assessed using a generalized least-squares model further adjusted for HIV-1 RNA and first ART regimen class. A total of 14,084 patients from 17 cohorts contributed data; 83% were male, 57% were nonwhite, and the median age was 40 years. Median BMI at ART initiation increased from 23.8 to 24.8 kg/m2 between 1998 and 2010 in NA-ACCORD, but the percentage of those obese (BMI ≥30 kg/m2) at ART initiation increased from 9% to 18%. After 3 years of ART, 22% of individuals with a normal BMI (18.5–24.9 kg/m2) at baseline had become overweight (BMI 25.0–29.9 kg/m2), and 18% of those overweight at baseline had become obese. HIV-infected white women had a higher BMI after 3 years of ART as compared to age-matched white women in NHANES (p = 0.02), while no difference in BMI after 3 years of ART was observed for HIV-infected men or non-white women compared to controls. The high prevalence of obesity we observed among ART-exposed HIV-infected adults in North America may contribute to health complications in the future. PMID:26352511

Vertebral Volumetric Bone Density and Strength Are Impaired in Women With Low-Weight and Atypical Anorexia Nervosa

PubMed Central

Bachmann, Katherine N.; Schorr, Melanie; Bruno, Alexander G.; Bredella, Miriam A.; Lawson, Elizabeth A.; Gill, Corey M.; Singhal, Vibha; Meenaghan, Erinne; Gerweck, Anu V.; Slattery, Meghan; Eddy, Kamryn T.; Ebrahimi, Seda; Koman, Stuart L.; Greenblatt, James M.; Keane, Robert J.; Weigel, Thomas; Misra, Madhusmita; Bouxsein, Mary L.; Klibanski, Anne

2017-01-01

Context: Areal bone mineral density (BMD) is lower, particularly at the spine, in low-weight women with anorexia nervosa (AN). However, little is known about vertebral integral volumetric BMD (Int.vBMD) or vertebral strength across the AN weight spectrum, including “atypical” AN [body mass index (BMI) ≥18.5 kg/m2]. Objective: To investigate Int.vBMD and vertebral strength, and their determinants, across the AN weight spectrum Design: Cross-sectional observational study Setting: Clinical research center Participants: 153 women (age 18 to 45): 64 with low-weight AN (BMI <18.5 kg/m2; 58% amenorrheic), 44 with atypical AN (18.5≤BMI<23 kg/m2; 30% amenorrheic), 45 eumenorrheic controls (19.2≤BMI<25 kg/m2). Measures: Int.vBMD and cross-sectional area (CSA) by quantitative computed tomography of L4; estimated vertebral strength (derived from Int.vBMD and CSA) Results: Int.vBMD and estimated vertebral strength were lowest in low-weight AN, intermediate in atypical AN, and highest in controls. CSA did not differ between groups; thus, vertebral strength (calculated using Int.vBMD and CSA) was driven by Int.vBMD. In AN, Int.vBMD and vertebral strength were associated positively with current BMI and nadir lifetime BMI (independent of current BMI). Int.vBMD and vertebral strength were lower in AN with current amenorrhea and longer lifetime amenorrhea duration. Among amenorrheic AN, Int.vBMD and vertebral strength were associated positively with testosterone. Conclusions: Int.vBMD and estimated vertebral strength (driven by Int.vBMD) are impaired across the AN weight spectrum and are associated with low BMI and endocrine dysfunction, both current and previous. Women with atypical AN experience diminished vertebral strength, partially due to prior low-weight and/or amenorrhea. Lack of current low-weight or amenorrhea in atypical AN does not preclude compromise of vertebral strength. PMID:27732336

Vertebral Volumetric Bone Density and Strength Are Impaired in Women With Low-Weight and Atypical Anorexia Nervosa.

PubMed

Bachmann, Katherine N; Schorr, Melanie; Bruno, Alexander G; Bredella, Miriam A; Lawson, Elizabeth A; Gill, Corey M; Singhal, Vibha; Meenaghan, Erinne; Gerweck, Anu V; Slattery, Meghan; Eddy, Kamryn T; Ebrahimi, Seda; Koman, Stuart L; Greenblatt, James M; Keane, Robert J; Weigel, Thomas; Misra, Madhusmita; Bouxsein, Mary L; Klibanski, Anne; Miller, Karen K

2017-01-01

Areal bone mineral density (BMD) is lower, particularly at the spine, in low-weight women with anorexia nervosa (AN). However, little is known about vertebral integral volumetric BMD (Int.vBMD) or vertebral strength across the AN weight spectrum, including "atypical" AN [body mass index (BMI) ≥18.5 kg/m2]. To investigate Int.vBMD and vertebral strength, and their determinants, across the AN weight spectrum. Cross-sectional observational study. Clinical research center. 153 women (age 18 to 45): 64 with low-weight AN (BMI <18.5 kg/m2; 58% amenorrheic), 44 with atypical AN (18.5≤BMI<23 kg/m2; 30% amenorrheic), 45 eumenorrheic controls (19.2≤BMI<25 kg/m2). Int.vBMD and cross-sectional area (CSA) by quantitative computed tomography of L4; estimated vertebral strength (derived from Int.vBMD and CSA). Int.vBMD and estimated vertebral strength were lowest in low-weight AN, intermediate in atypical AN, and highest in controls. CSA did not differ between groups; thus, vertebral strength (calculated using Int.vBMD and CSA) was driven by Int.vBMD. In AN, Int.vBMD and vertebral strength were associated positively with current BMI and nadir lifetime BMI (independent of current BMI). Int.vBMD and vertebral strength were lower in AN with current amenorrhea and longer lifetime amenorrhea duration. Among amenorrheic AN, Int.vBMD and vertebral strength were associated positively with testosterone. Int.vBMD and estimated vertebral strength (driven by Int.vBMD) are impaired across the AN weight spectrum and are associated with low BMI and endocrine dysfunction, both current and previous. Women with atypical AN experience diminished vertebral strength, partially due to prior low-weight and/or amenorrhea. Lack of current low-weight or amenorrhea in atypical AN does not preclude compromise of vertebral strength. Copyright © 2017 by the Endocrine Society

Rising Obesity Prevalence and Weight Gain Among Adults Starting Antiretroviral Therapy in the United States and Canada.

PubMed

Koethe, John R; Jenkins, Cathy A; Lau, Bryan; Shepherd, Bryan E; Justice, Amy C; Tate, Janet P; Buchacz, Kate; Napravnik, Sonia; Mayor, Angel M; Horberg, Michael A; Blashill, Aaron J; Willig, Amanda; Wester, C William; Silverberg, Michael J; Gill, John; Thorne, Jennifer E; Klein, Marina; Eron, Joseph J; Kitahata, Mari M; Sterling, Timothy R; Moore, Richard D

2016-01-01

The proportion of overweight and obese adults in the United States and Canada has increased over the past decade, but temporal trends in body mass index (BMI) and weight gain on antiretroviral therapy (ART) among HIV-infected adults have not been well characterized. We conducted a cohort study comparing HIV-infected adults in the North America AIDS Cohort Collaboration on Research and Design (NA-ACCORD) to United States National Health and Nutrition Examination Survey (NHANES) controls matched by sex, race, and age over the period 1998 to 2010. Multivariable linear regression assessed the relationship between BMI and year of ART initiation, adjusting for sex, race, age, and baseline CD4(+) count. Temporal trends in weight on ART were assessed using a generalized least-squares model further adjusted for HIV-1 RNA and first ART regimen class. A total of 14,084 patients from 17 cohorts contributed data; 83% were male, 57% were nonwhite, and the median age was 40 years. Median BMI at ART initiation increased from 23.8 to 24.8 kg/m(2) between 1998 and 2010 in NA-ACCORD, but the percentage of those obese (BMI ≥30 kg/m(2)) at ART initiation increased from 9% to 18%. After 3 years of ART, 22% of individuals with a normal BMI (18.5-24.9 kg/m(2)) at baseline had become overweight (BMI 25.0-29.9 kg/m(2)), and 18% of those overweight at baseline had become obese. HIV-infected white women had a higher BMI after 3 years of ART as compared to age-matched white women in NHANES (p = 0.02), while no difference in BMI after 3 years of ART was observed for HIV-infected men or non-white women compared to controls. The high prevalence of obesity we observed among ART-exposed HIV-infected adults in North America may contribute to health complications in the future.

Associations between Family-Related Factors, Breakfast Consumption and BMI among 10- to 12-Year-Old European Children: The Cross-Sectional ENERGY-Study

PubMed Central

Van Lippevelde, Wendy; Te Velde, Saskia J.; Verloigne, Maïté; Van Stralen, Maartje M.; De Bourdeaudhuij, Ilse; Manios, Yannis; Bere, Elling; Vik, Froydis N.; Jan, Nataša; Fernández Alvira, Juan M.; Chinapaw, Mai J. M.; Bringolf-Isler, Bettina; Kovacs, Eva; Brug, Johannes; Maes, Lea

2013-01-01

Objective To investigate associations of family-related factors with children’s breakfast consumption and BMI-z-score and to examine whether children’s breakfast consumption mediates associations between family-related factors and children’s BMI-z-score. Subjects Ten- to twelve-year-old children (n = 6374; mean age = 11.6±0.7 years, 53.2% girls, mean BMI-z-score = 0.4±1.2) and one of their parents (n = 6374; mean age = 41.4±5.3 years, 82.7% female, mean BMI = 24.5±4.2 kg/m2) were recruited from schools in eight European countries (Belgium, Greece, Hungary, the Netherlands, Norway, Slovenia, Spain, and Switzerland). The children self-reported their breakfast frequency per week. The body weight and height of the children were objectively measured. The parents responded to items on family factors related to breakfast (automaticity, availability, encouragement, paying attention, permissiveness, negotiating, communicating health beliefs, parental self-efficacy to address children’s nagging, praising, and family breakfast frequency). Mediation analyses were performed using multi-level regression analyses (child-school-country). Results Three of the eleven family-related variables were significantly associated with children’s BMI-z-score. The family breakfast frequency was negatively associated with the BMI-z-score; permissiveness concerning skipping breakfast and negotiating about breakfast were positively associated with the BMI-z-score. Children’s breakfast consumption was found to be a mediator of the two associations. All family-related variables except for negotiating, praising and communicating health beliefs, were significantly associated with children’s breakfast consumption. Conclusions Future breakfast promotion and obesity prevention interventions should focus on family-related factors including the physical home environment and parenting practices. Nevertheless, more longitudinal research and intervention studies to support these findings between family-related factors and both children’s breakfast consumption and BMI-z-score are needed. PMID:24282508

Change in BMI accurately predicted by social exposure to acquaintances.

PubMed

Oloritun, Rahman O; Ouarda, Taha B M J; Moturu, Sai; Madan, Anmol; Pentland, Alex Sandy; Khayal, Inas

2013-01-01

Research has mostly focused on obesity and not on processes of BMI change more generally, although these may be key factors that lead to obesity. Studies have suggested that obesity is affected by social ties. However these studies used survey based data collection techniques that may be biased toward select only close friends and relatives. In this study, mobile phone sensing techniques were used to routinely capture social interaction data in an undergraduate dorm. By automating the capture of social interaction data, the limitations of self-reported social exposure data are avoided. This study attempts to understand and develop a model that best describes the change in BMI using social interaction data. We evaluated a cohort of 42 college students in a co-located university dorm, automatically captured via mobile phones and survey based health-related information. We determined the most predictive variables for change in BMI using the least absolute shrinkage and selection operator (LASSO) method. The selected variables, with gender, healthy diet category, and ability to manage stress, were used to build multiple linear regression models that estimate the effect of exposure and individual factors on change in BMI. We identified the best model using Akaike Information Criterion (AIC) and R(2). This study found a model that explains 68% (p<0.0001) of the variation in change in BMI. The model combined social interaction data, especially from acquaintances, and personal health-related information to explain change in BMI. This is the first study taking into account both interactions with different levels of social interaction and personal health-related information. Social interactions with acquaintances accounted for more than half the variation in change in BMI. This suggests the importance of not only individual health information but also the significance of social interactions with people we are exposed to, even people we may not consider as close friends.

Urban sprawl and body mass index among displaced Hurricane Katrina survivors.

PubMed

Arcaya, Mariana; James, Peter; Rhodes, Jean E; Waters, Mary C; Subramanian, S V

2014-08-01

Existing research suggests that walkable environments are protective against weight gain, while sprawling neighborhoods may pose health risks. Using prospective data on displaced Hurricane Katrina survivors, we provide the first natural experimental data on sprawl and body mass index (BMI). The analysis uses prospectively collected pre- (2003-2005) and post-hurricane (2006-2007) data from the Resilience in Survivors of Katrina (RISK) project on 280 displaced Hurricane Katrina survivors who had little control over their neighborhood placement immediately after the disaster. The county sprawl index, a standardized measure of built environment, was used to predict BMI at follow-up, adjusted for baseline BMI and sprawl; hurricane-related trauma; and demographic and economic characteristics. Respondents from 8 New Orleans-area counties were dispersed to 76 counties post-Katrina. Sprawl increased by an average of 1.5 standard deviations (30 points) on the county sprawl index. Each one point increase in sprawl was associated with approximately .05kg/m(2) higher BMI in unadjusted models (95%CI: .01-.08), and the relationship was not attenuated after covariate adjustment. We find a robust association between residence in a sprawling county and higher BMI unlikely to be caused by self-selection into neighborhoods, suggesting that the built environment may foster changes in weight. Copyright © 2014 Elsevier Inc. All rights reserved.

Polycystic ovary syndrome patients with high BMI tend to have functional disorders of androgen excess: a prospective study.

PubMed

Yuan, Chun; Liu, Xiaoqiang; Mao, Yundong; Diao, Feiyang; Cui, Yugui; Liu, Jiayin

2016-05-01

Biochemical or clinical changes of hyperandrogenism are important elements of polycystic ovary syndrome (PCOS). There is currently no consensus on the definition and diagnostic criteria of hyperandrogenism in PCOS. The aim of this study was to investigate the complex symptoms of hyperandrogenic disorders and the correlations between metabolism and hyperandrogenism in patients with PCOS from an outpatient reproductive medicine clinic in China. We conducted a case control study of 125 PCOS patients and 130 controls to evaluate differences in body mass index (BMI), total testosterone (TT), modified Ferriman-Gallwey hirsutism score, sex hormone binding globulin (SHBG), homeostasis model assessment-estimated insulin resistance (HOMA-IR) and free androgen index (FAI) between PCOS patients and controls and subgroups of PCOS. The prevalence of acne and hirsutism did not differ significantly between the hyperandrogenic and non-hyperandrogenic subgroup. Patients with signs of hyperandrogenism had significantly higher BMI (P < 0.05), but differences in TT, SHBG, FAI and waist/hip ratio were insignificant. The odds ratio of overweight was calculated for all PCOS patients. Our results suggest that PCOS patients with high BMI tend to have functional disorders of androgen excess; therefore, BMI may be a strong predictor of hyperandrogenism in PCOS. © 2016 the Journal of Biomedical Research. All rights reserved.

Urban Sprawl and Body Mass Index Among Displaced Hurricane Katrina Survivors

PubMed Central

Arcaya, Mariana; James, Peter; Rhodes, Jean; Waters, Mary C; Subramanian, S V

2014-01-01

Objective Existing research suggests that walkable environments are protective against weight gain, while sprawling neighborhoods may pose health risks. Using prospective data on displaced Hurricane Katrina survivors, we provide the first natural experimental data on sprawl and body mass index (BMI). Methods The analysis uses prospectively collected pre- (2003–2005) and post-hurricane (2006–2007) data from the Resilience in Survivors of Katrina (RISK) project on 280 displaced Hurricane Katrina survivors who had little control over their neighborhood placement immediately after the disaster. The county sprawl index, a standardized measure of built environment, was used to predict BMI at follow-up, adjusted for baseline BMI and sprawl; Hurricane-related trauma; and demographic and economic characteristics. Results Respondents from 8 New Orleans-area counties were dispersed to 76 counties post-Katrina. Sprawl increased by an average of 1.5 standard deviations (30 points) on the county sprawl index. Each one point increase in sprawl was associated with approximately .05 kg/m2 higher BMI in unadjusted models (95%CI: .01–.08), and the relationship was not attenuated after covariate adjustment. Conclusions We find a robust association between residence in a sprawling county and higher BMI unlikely to be caused by self-selection into neighborhoods, suggesting that the built environment may foster changes in weight. PMID:24732717

The Role of BMI Change on Smoking Abstinence in a Sample of HIV-Infected Smokers

PubMed Central

Gritz, Ellen R.; Kypriotakis, George; Arduino, Roberto C.; Vidrine, Damon J.

2016-01-01

The prevalence of cigarette smoking among persons living with HIV/AIDS (PLWHA) is approximately 40%, significantly higher than that of the general population. Identifying predictors of successful smoking cessation for PLWHA is necessary to alleviate the morbidity and mortality associated with smoking in this population. Weight gain has been associated with smoking relapse in the general population, but has not been studied among PLWHA. Data from 474 PLWHA enrolled in a smoking cessation randomized clinical trial were analyzed to examine the effect of BMI change, from baseline to 3-month follow-up, on smoking outcomes using multiple logistic regression. The odds of 7-day smoking abstinence at 3-month follow-up were 4.22 (95% CI=1.65, 10.82) times higher for participants classified as BMI decrease and 4.22 (95% CI=1.62, 11.01) times higher for participants classified as BMI increase as compared to participants with a minimal increase or decrease in BMI. In this sample, both weight gain and loss following smoking cessation were significantly associated with abstinence at 3-month follow-up among HIV-infected smokers. Further research and a better understanding of predictors of abstinence will encourage more tailored interventions, with the potential to reduce morbidity and mortality. PMID:26666313

Higher weight, lower education: a longitudinal association between adolescents' body mass index and their subsequent educational achievement level?

PubMed

Larsen, Junilla K; Kleinjan, Marloes; Engels, Rutger C M E; Fisher, Jennifer O; Hermans, Roel C J

2014-12-01

The purpose of this study was to examine the association between adolescents' body mass index (BMI) z-scores and their subsequent level of schooling, extending previous longitudinal research by using objectively measured weight and height data. A longitudinal study with 3 study waves (1-year intervals) involving 1248 Dutch adolescents (49% girls; mean age = 13.7 years) at schools providing different educational levels was used to determine adolescents who moved and did not move to a lower educational level in the first year, or in the second year, and to examine whether this movement could be predicted by BMI z-scores (zBMI), after controlling for a large range of potential confounding factors. A total of 1164 Dutch adolescents continued in the same level of education, whereas 84 adolescents moved to a lower educational level (43 moved in the first and 41 in the second year). A higher zBMI significantly increased the risk of a general transition to a lower educational level, and of a transition in the first year, but not in the second year, after controlling for potential demographic, behavioral, and psychological confounds. Findings suggest that a higher zBMI during adolescence immediately lowers educational achievement level during general secondary education. © 2014, American School Health Association.

Body mass index had different effects on premenopausal and postmenopausal breast cancer risks: a dose-response meta-analysis with 3,318,796 subjects from 31 cohort studies.

PubMed

Chen, Yanzi; Liu, Li; Zhou, Quan; Imam, Mustapha Umar; Cai, Jialin; Wang, Yaxuan; Qi, Minjie; Sun, Panpan; Ping, Zhiguang; Fu, Xiaoli

2017-12-08

There is sufficient evidence supporting a relationship between increased body mass index (BMI) and an increased risk for breast cancer among postmenopausal women. However, most studies have found a decreased risk for premenopausal breast cancer. This study was conducted to find out the different effects of BMI on the risk of breast cancer among premenopausal and postmenopausal women, and explore the potential factors that influence the associations. A dose-response meta-analysis with 3,318,796 participants from 31 articles was conducted. Cohort studies that included BMI and corresponding breast cancer risk were selected through various databases including PubMed, Medline, Web of Science, the China National Knowledge Infrastructure (CNKI) and Chinese Scientific Journals (VIP). Random effects models were used for analyzing the data. The summary relative risks (RRs) were 1.33 (95%CI: 1.20-1.48) and 0.94(95%CI: 0.80-1.11) among postmenopausal and premenopausal women, respectively. The dose-response meta-analysis indicated a positive non-linear association between BMI and breast cancer risk among postmenopausal women, and compared to the mean level of the normal BMI category (21.5 kg/m 2 ) the RR in total postmenopausal women were1.03 (95% CI: 1.02-1.05) per 1 kg/m 2 increment. However, no statistically significant association among total premenopausal women was detected. In subgroup analysis among European premenopausal women, the summary RR was 0.79(95%CI: 0.70-0.88). The non-linear relationship showed a negative non-linear association between BMI and breast cancer risk among European premenopausal women. When compared to the mean level of the normal BMI category, the RRs were 0.98 (95%CI: 0.96-1.00) per 1 kg/m 2 increment, respectively. In line with previous studies BMI had different effects on pre-menopausal and postmenopausal breast cancer risk. However, contrary to previous studies, a high BMI was not associated with decreased risk in total pre-menopausal women. More research is needed to better understand these differences.

Food Shopping and Acquisition Behaviors in Relation to BMI among Residents of Low-Income Communities in South Carolina.

PubMed

Liese, Angela D; Ma, Xiaonan; Hutto, Brent; Sharpe, Patricia A; Bell, Bethany A; Wilcox, Sara

2017-09-16

Low-income areas in which residents have poor access to healthy foods have been referred to as "food deserts." It is thought that improving food access may help curb the obesity epidemic. Little is known about where residents of food deserts shop and if shopping habits are associated with body mass index (BMI). We evaluated the association of food shopping and acquisition (e.g., obtaining food from church, food pantries, etc.) with BMI among 459 residents of low-income communities from two South Carolina counties, 81% of whom lived in United States Department of Agriculture-designated food deserts. Participants were interviewed about food shopping and acquisition and perceptions of their food environment, and weight and height were measured. Distances to food retail outlets were determined. Multivariable linear regression analysis was employed. Our study sample comprising largely African-American women had an average BMI of 32.5 kg/m². The vast majority of study participants shopped at supermarkets (61%) or supercenters/warehouse clubs (27%). Shopping at a supercenter or warehouse club as one's primary store was significantly associated with a 2.6 kg/m² higher BMI compared to shopping at a supermarket, independent of demographics, socioeconomics, physical activity, and all other food shopping/acquisition behaviors. Persons who reported shopping at a small grocery store or a convenience or dollar store as their tertiary store had a 2.6 kg/m² lower BMI. Respondents who perceived lack of access to adequate food shopping in their neighborhoods as a problem had higher BMI. Living in a food desert census tract was not significantly associated with BMI. Other shopping attributes, including distance to utilized and nearest grocery stores, were not independently associated with BMI. These findings call into question the idea that poor spatial access to grocery stores is a key underlying factor affecting the obesity epidemic. Future research should consider assessing foods purchased and dietary intake within a comprehensive study of food shopping behaviors and health outcomes among persons living in food deserts.

[Nutritional status of children in the North Backa Region based on the body mass index].

PubMed

Pavlović, M

2000-01-01

Monitoring nutritional status of children at a population level represents an important index of the nutritional quality and quantity in a certain period of time. The aim of this paper was to determine the body mass index (BMI kg/m2) and evaluate the nutritional status of children in the North Backa Region (Subotica, Backa Topola and Mali Idos). A transversal anthropometric study examining body weight and height during a mass screening of children in Health centers in the North Backa Region, 25.790 children aged 1-18 have been examined in the period 1995-1998. Evidence and statistical evaluation of data have been processed using the software "CHILD" determining the percentile values of BMI and nutritional status according to reference values of the First National Healts and Nutrition Examination Survey (NHANES 1). Analyzing the nutritional status of children aged 6-18 in the North Backa Region we found 4.39% boys and 5.41 girls with BMI < P5 as underweight, moderate underweight with BMI P5-15 were 7.28% boys and 6.96% girls, whereas normal nutritional status (BMI P15-85) was found in 67.13% boys and 67.25% girls. 12.77% of boys and 11.78% of girls were overweight (BMI P85-95) and obesity (BMI > P95) was registered in 8.46% boys and 8.60% girls. Using the same software and based on results for the whole group of children aged 1-18, reference values were calculated for BMI as a regional reference data which can be used in everyday public health setting. This research is the first examination of the nutritional status of children at a population level in the North Backa Region in regard to BMI. This model of nutritional status monitoring in children using the above mentioned software will be used at a national level. These results show an inadequate nutritional status of children in the North Backa Region which can be associated with unbalanced nutrition and life style. Therefore, permanent monitoring of the nutritional status in children has been established in order to take adequate preventive measures to realize nutrition of children and adolescents.

Genome-wide association study for the interaction between BMR and BMI in obese Korean women including overweight.

PubMed

Lee, Myoungsook; Kwon, Dae Young; Kim, Myung-Sunny; Choi, Chong Ran; Park, Mi-Young; Kim, Ae-Jung

2016-02-01

This is the first study to identify common genetic factors associated with the basal metabolic rate (BMR) and body mass index (BMI) in obese Korean women including overweight. This will be a basic study for future research of obese gene-BMR interaction. The experimental design was 2 by 2 with variables of BMR and BMI. A genome-wide association study (GWAS) of single nucleotide polymorphisms (SNPs) was conducted in the overweight and obesity (BMI > 23 kg/m(2)) compared to the normality, and in women with low BMR (< 1426.3 kcal/day) compared to high BMR. A total of 140 SNPs reached formal genome-wide statistical significance in this study (P < 1 × 10(-4)). Surveys to estimate energy intake using 24-h recall method for three days and questionnaires for family history, a medical examination, and physical activities were conducted. We found that two NRG3 gene SNPs in the 10q23.1 chromosomal region were highly associated with BMR (rs10786764; P = 8.0 × 10(-7), rs1040675; 2.3 × 10(-6)) and BMI (rs10786764; P = 2.5 × 10(-5), rs10786764; 6.57 × 10(-5)). The other genes related to BMI (HSD52, TMA16, MARCH1, NRG1, NRXN3, and STK4) yielded P <10 × 10(-4). Five new loci associated with BMR and BMI, including NRG3, OR8U8, BCL2L2-PABPN1, PABPN1, and SLC22A17 were identified in obese Korean women (P < 1 × 10(-4)). In the questionnaire investigation, significant differences were found in the number of starvation periods per week, family history of stomach cancer, coffee intake, and trial of weight control in each group. We discovered several common BMR- and BMI-related genes using GWAS. Although most of these newly established loci were not previously associated with obesity, they may provide new insights into body weight regulation. Our findings of five common genes associated with BMR and BMI in Koreans will serve as a reference for replication and validation of future studies on the metabolic rate.

Bidirectional association between parental child-feeding practices and body mass index at 4 and 7 y of age.

PubMed

Afonso, Lisa; Lopes, Carla; Severo, Milton; Santos, Susana; Real, Helena; Durão, Catarina; Moreira, Pedro; Oliveira, Andreia

2016-03-01

Evidence of the association between parental child-feeding practices and the child's body mass index (BMI) is controversial, and bidirectional effects have been poorly studied. We aimed to examine bidirectional associations between parental child-feeding practices and BMI at 4 and 7 y of age. This study included 3708 singleton children from the Generation XXI birth cohort with data on parental child-feeding practices and BMI at 4 and 7 y old. Feeding practices were assessed through a self-administered questionnaire by combining the Child Feeding Questionnaire and the Overt/Covert Control scale and then adapting it to Portuguese preschool children. Weight and height were measured according to standardized procedures, and age- and sex-specific BMI z scores were computed based on the WHO Growth References. Linear regression models were used to estimate the bidirectional associations between each practice and BMI z score. Crosslagged analyses were performed to compare the directions of those associations (the mean score of each practice and BMI z score at both ages were standardized to enable effect size comparisons). After adjustments, pressure to eat and overt control at 4 y of age were associated with a lower BMI z score 3 y later (β: -0.05; 95% CI: -0.08, -0.03 and β: -0.05; 95% CI: -0.09, -0.01, respectively). Regarding the opposite direction of association, a higher BMI z score at 4 y of age was significantly associated with higher levels of restriction and covert control at 7 y of age (β: 0.06; 95% CI: 0.03, 0.08 and β: 0.06; 95% CI: 0.04, 0.08, respectively) and with lower levels of pressure to eat (β: -0.17; 95% CI: -0.20, -0.15). The only bidirectional practice, pressure to eat, was more strongly influenced by the BMI z score than the reverse (βstandardized: -0.17 compared with βstandardized: -0.04; likelihood ratio test: P < 0.001). We found that parents both respond to and influence the child's weight; thus, this child-parent interaction should be considered in future research. © 2016 American Society for Nutrition.

Food Shopping and Acquisition Behaviors in Relation to BMI among Residents of Low-Income Communities in South Carolina

PubMed Central

Liese, Angela D.; Ma, Xiaonan; Hutto, Brent; Sharpe, Patricia A.; Bell, Bethany A.; Wilcox, Sara

2017-01-01

Low-income areas in which residents have poor access to healthy foods have been referred to as “food deserts.” It is thought that improving food access may help curb the obesity epidemic. Little is known about where residents of food deserts shop and if shopping habits are associated with body mass index (BMI). We evaluated the association of food shopping and acquisition (e.g., obtaining food from church, food pantries, etc.) with BMI among 459 residents of low-income communities from two South Carolina counties, 81% of whom lived in United States Department of Agriculture-designated food deserts. Participants were interviewed about food shopping and acquisition and perceptions of their food environment, and weight and height were measured. Distances to food retail outlets were determined. Multivariable linear regression analysis was employed. Our study sample comprising largely African-American women had an average BMI of 32.5 kg/m2. The vast majority of study participants shopped at supermarkets (61%) or supercenters/warehouse clubs (27%). Shopping at a supercenter or warehouse club as one’s primary store was significantly associated with a 2.6 kg/m2 higher BMI compared to shopping at a supermarket, independent of demographics, socioeconomics, physical activity, and all other food shopping/acquisition behaviors. Persons who reported shopping at a small grocery store or a convenience or dollar store as their tertiary store had a 2.6 kg/m2 lower BMI. Respondents who perceived lack of access to adequate food shopping in their neighborhoods as a problem had higher BMI. Living in a food desert census tract was not significantly associated with BMI. Other shopping attributes, including distance to utilized and nearest grocery stores, were not independently associated with BMI. These findings call into question the idea that poor spatial access to grocery stores is a key underlying factor affecting the obesity epidemic. Future research should consider assessing foods purchased and dietary intake within a comprehensive study of food shopping behaviors and health outcomes among persons living in food deserts. PMID:28926937

Life-Course Body Mass Index Trajectories Are Predicted by Childhood Socioeconomic Status but Not Exposure to Improved Nutrition during the First 1000 Days after Conception in Guatemalan Adults.

PubMed

Ford, Nicole D; Martorell, Reynaldo; Mehta, Neil K; Ramirez-Zea, Manuel; Stein, Aryeh D

2016-11-01

Latin America has experienced increases in obesity. Little is known about the role of early life factors on body mass index (BMI) gain over the life course. The objective of this research was to examine the role of early life factors [specifically, nutrition supplementation during the first 1000 d (from conception to 2 y of age) and childhood household socioeconomic status (SES)] on the pattern of BMI gain from birth or early childhood through midadulthood by using latent class growth analysis. Study participants (711 women, 742 men) who were born in 4 villages in Guatemala (1962-1977) were followed prospectively since participating in a randomized nutrition supplementation trial as children. Sex-specific BMI latent class trajectories were derived from 22 possible measures of height and weight from 1969 to 2004. To characterize early life determinants of BMI latent class membership, we used logistic regression modeling and estimated the difference-in-difference (DD) effect of nutrition supplementation during the first 1000 d. We identified 2 BMI latent classes in women [low (57%) and high (43%)] and 3 classes in men [low (38%), medium (47%), and high (15%)]. Nutrition supplementation during the first 1000 d after conception was not associated with BMI latent class membership (DD test: P > 0.15 for men and women), whereas higher SES was associated with increased odds of high BMI latent class membership in both men (OR: 1.98; 95% CI: 1.09, 3.61) and women (OR: 1.62; 95% CI: 1.07, 2.45) for the highest relative to the lowest tertile. In a cohort of Guatemalan men and women, nutrition supplementation provided during the first 1000 d was not significantly associated with higher BMI trajectory. Higher childhood household SES was associated with increased odds of high BMI latent class membership relative to the poorest households. The pathways through which this operates still need to be explored. © 2016 American Society for Nutrition.

The Neighborhood Energy Balance Equation: Does Neighborhood Food Retail Environment + Physical Activity Environment = Obesity? The CARDIA Study

PubMed Central

Boone-Heinonen, Janne; Diez-Roux, Ana V.; Goff, David C.; Loria, Catherine M.; Kiefe, Catarina I.; Popkin, Barry M.; Gordon-Larsen, Penny

2013-01-01

Background Recent obesity prevention initiatives focus on healthy neighborhood design, but most research examines neighborhood food retail and physical activity (PA) environments in isolation. We estimated joint, interactive, and cumulative impacts of neighborhood food retail and PA environment characteristics on body mass index (BMI) throughout early adulthood. Methods and Findings We used cohort data from the Coronary Artery Risk Development in Young Adults (CARDIA) Study [n=4,092; Year 7 (24-42 years, 1992-1993) followed over 5 exams through Year 25 (2010-2011); 12,921 person-exam observations], with linked time-varying geographic information system-derived neighborhood environment measures. Using regression with fixed effects for individuals, we modeled time-lagged BMI as a function of food and PA resource density (counts per population) and neighborhood development intensity (a composite density score). We controlled for neighborhood poverty, individual-level sociodemographics, and BMI in the prior exam; and included significant interactions between neighborhood measures and by sex. Using model coefficients, we simulated BMI reductions in response to single and combined neighborhood improvements. Simulated increase in supermarket density (from 25th to 75th percentile) predicted inter-exam reduction in BMI of 0.09 kg/m2 [estimate (95% CI): -0.09 (-0.16, -0.02)]. Increasing commercial PA facility density predicted BMI reductions up to 0.22 kg/m2 in men, with variation across other neighborhood features [estimate (95% CI) range: -0.14 (-0.29, 0.01) to -0.22 (-0.37, -0.08)]. Simultaneous increases in supermarket and commercial PA facility density predicted inter-exam BMI reductions up to 0.31 kg/m2 in men [estimate (95% CI) range: -0.23 (-0.39, -0.06) to -0.31 (-0.47, -0.15)] but not women. Reduced fast food restaurant and convenience store density and increased public PA facility density and neighborhood development intensity did not predict reductions in BMI. Conclusions Findings suggest that improvements in neighborhood food retail or PA environments may accumulate to reduce BMI, but some neighborhood changes may be less beneficial to women. PMID:24386458

Differential associations of fast food and restaurant food consumption with 3-y change in body mass index: the Coronary Artery Risk Development in Young Adults Study.

PubMed

Duffey, Kiyah J; Gordon-Larsen, Penny; Jacobs, David R; Williams, O Dale; Popkin, Barry M

2007-01-01

Away-from-home food consumption has rapidly increased, though little is known about the independent associations of restaurant food and fast food intake with body mass index (BMI) and BMI change. The aim was to compare the associations of restaurant food and fast food consumption with current and 3-y changes in BMI. Multivariate linear regression models, with control for demographic and lifestyle factors, were used to examine cross-sectional and longitudinal associations of away-from-home eating with BMI by using data from subjects of the Coronary Artery Risk Development in Young Adults Study (n = 3394) obtained at exam years 7 (1992-1993) and 10 (1995-1996). Forty percent of the sample increased their weekly consumption of restaurant or fast food, though mean (+/-SD) changes were -0.16 +/- 2.39 times/wk (P = 0.0001) and -0.56 +/- 3.04 times/wk (P < 0.0001), respectively. Cross-sectionally, fast food, but not restaurant food, consumption was positively associated with BMI. Similarly, higher consumption of fast food at year 7 was associated with a 0.16-unit higher BMI at year 10. After adjustment for baseline away-from-home eating, increased consumption of fast food only (beta: 0.20; 95% CI: 0.01, 0.39) and of both restaurant food and fast food (beta: 0.29; 95% CI: 0.06, 0.51) were positively associated with BMI change, though the estimates were not significantly different (P = 0.47). Increased consumption of restaurant food only was unrelated to BMI change (beta: -0.01; 95% CI: -0.21, 0.19), which differed significantly (P = 0.014) from the estimate for an increase in both restaurant food and fast food intake. We found differential effects of restaurant food and fast food intakes on BMI, although the observed differences were not always statistically significant. More research is needed to determine whether the differential effects are related to consumer characteristics or the food itself.

Walking Capacity of Bariatric Surgery Candidates

PubMed Central

King, WC; Engel, SG; Elder, KA; Chapman, WH; Eid, GM; Wolfe, BM; Belle, SH

2011-01-01

Background This study characterizes the walking limitations of bariatric surgery candidates by age and body mass index (BMI) and determines factors independently associated with walking capacity. Setting Multi-institutional at research university hospitals in the United States. Methods 2458 participants of the Longitudinal Assessment of Bariatric Surgery study (age: 18-78 y, BMI: 33-94 kg/m2) attended a pre-operative research visit. Walking capacity was measured via self-report and the 400 meter Long Distance Corridor Walk (LDCW). Results Almost two-thirds (64%) of subjects reported limitations walking several blocks, 48% had an objectively-defined mobility deficit, and 16% reported at least some walking aid use. In multivariable analysis, BMI, older age, lower income and greater bodily pain were independently associated (p<.05) with walking aid use, physical discomfort during the LDCW, inability to complete the LDCW, and slower time to complete the LDCW. Female sex, Hispanic ethnicity (but not race), higher resting heart rate, history of smoking, several comoribidities (history of stroke, ischemic heart disease, diabetes, asthma, sleep apnea, venous edema with ulcerations), and depressive symptoms were also independently related (p<.05) to at least one measure of reduced walking capacity. Conclusions Walking limitations are common in bariatric surgery candidates, even among the least severely obese and youngest patients. Physical activity counseling must be tailored to individuals' abilities. While several factors identified in this study (e.g., BMI, age, pain, comorbidities) should be considered, directly assessing walking capacity will facilitate appropriate goal-setting. PMID:21937285

Crowdsourcing novel childhood predictors of adult obesity.

PubMed

Bevelander, Kirsten E; Kaipainen, Kirsikka; Swain, Robert; Dohle, Simone; Bongard, Josh C; Hines, Paul D H; Wansink, Brian

2014-01-01

Effective and simple screening tools are needed to detect behaviors that are established early in life and have a significant influence on weight gain later in life. Crowdsourcing could be a novel and potentially useful tool to assess childhood predictors of adult obesity. This exploratory study examined whether crowdsourcing could generate well-documented predictors in obesity research and, moreover, whether new directions for future research could be uncovered. Participants were recruited through social media to a question-generation website, on which they answered questions and were able to pose new questions that they thought could predict obesity. During the two weeks of data collection, 532 participants (62% female; age  =  26.5±6.7; BMI  =  29.0±7.0) registered on the website and suggested a total of 56 unique questions. Nineteen of these questions correlated with body mass index (BMI) and covered several themes identified by prior research, such as parenting styles and healthy lifestyle. More importantly, participants were able to identify potential determinants that were related to a lower BMI, but have not been the subject of extensive research, such as parents packing their children's lunch to school or talking to them about nutrition. The findings indicate that crowdsourcing can reproduce already existing hypotheses and also generate ideas that are less well documented. The crowdsourced predictors discovered in this study emphasize the importance of family interventions to fight obesity. The questions generated by participants also suggest new ways to express known predictors.

Research interface on a programmable ultrasound scanner.

PubMed

Shamdasani, Vijay; Bae, Unmin; Sikdar, Siddhartha; Yoo, Yang Mo; Karadayi, Kerem; Managuli, Ravi; Kim, Yongmin

2008-07-01

Commercial ultrasound machines in the past did not provide the ultrasound researchers access to raw ultrasound data. Lack of this ability has impeded evaluation and clinical testing of novel ultrasound algorithms and applications. Recently, we developed a flexible ultrasound back-end where all the processing for the conventional ultrasound modes, such as B, M, color flow and spectral Doppler, was performed in software. The back-end has been incorporated into a commercial ultrasound machine, the Hitachi HiVision 5500. The goal of this work is to develop an ultrasound research interface on the back-end for acquiring raw ultrasound data from the machine. The research interface has been designed as a software module on the ultrasound back-end. To increase the amount of raw ultrasound data that can be spooled in the limited memory available on the back-end, we have developed a method that can losslessly compress the ultrasound data in real time. The raw ultrasound data could be obtained in any conventional ultrasound mode, including duplex and triplex modes. Furthermore, use of the research interface does not decrease the frame rate or otherwise affect the clinical usability of the machine. The lossless compression of the ultrasound data in real time can increase the amount of data spooled by approximately 2.3 times, thus allowing more than 6s of raw ultrasound data to be acquired in all the modes. The interface has been used not only for early testing of new ideas with in vitro data from phantoms, but also for acquiring in vivo data for fine-tuning ultrasound applications and conducting clinical studies. We present several examples of how newer ultrasound applications, such as elastography, vibration imaging and 3D imaging, have benefited from this research interface. Since the research interface is entirely implemented in software, it can be deployed on existing HiVision 5500 ultrasound machines and may be easily upgraded in the future. The developed research interface can aid researchers in the rapid testing and clinical evaluation of new ultrasound algorithms and applications. Additionally, we believe that our approach would be applicable to designing research interfaces on other ultrasound machines.

Childhood Obesity Research Demonstration (CORD): Evaluation plan

USDA-ARS?s Scientific Manuscript database

The Childhood Obesity Research Demonstration (CORD) project evaluation will determine the extent to which the CORD model of linking primary care (PC) interventions to public health (PH) interventions in multiple community sectors affects BMI and behavior in children (2 to 12 years). The evaluation c...

Exploiting co-adaptation for the design of symbiotic neuroprosthetic assistants.

PubMed

Sanchez, Justin C; Mahmoudi, Babak; DiGiovanna, Jack; Principe, Jose C

2009-04-01

The success of brain-machine interfaces (BMI) is enabled by the remarkable ability of the brain to incorporate the artificial neuroprosthetic 'tool' into its own cognitive space and use it as an extension of the user's body. Unlike other tools, neuroprosthetics create a shared space that seamlessly spans the user's internal goal representation of the world and the external physical environment enabling a much deeper human-tool symbiosis. A key factor in the transformation of 'simple tools' into 'intelligent tools' is the concept of co-adaptation where the tool becomes functionally involved in the extraction and definition of the user's goals. Recent advancements in the neuroscience and engineering of neuroprosthetics are providing a blueprint for how new co-adaptive designs based on reinforcement learning change the nature of a user's ability to accomplish tasks that were not possible using conventional methodologies. By designing adaptive controls and artificial intelligence into the neural interface, tools can become active assistants in goal-directed behavior and further enhance human performance in particular for the disabled population. This paper presents recent advances in computational and neural systems supporting the development of symbiotic neuroprosthetic assistants.

Effect of Treatment of Gestational Diabetes Mellitus on Obesity in the Next Generation

PubMed Central

Gillman, Matthew W.; Oakey, Helena; Baghurst, Peter A.; Volkmer, Robert E.; Robinson, Jeffrey S.; Crowther, Caroline A.

2010-01-01

OBJECTIVE Gestational diabetes mellitus (GDM) may cause obesity in the offspring. The objective was to assess the effect of treatment for mild GDM on the BMI of 4- to 5-year-old children. RESEARCH DESIGN AND METHODS Participants were 199 mothers who participated in a randomized controlled trial of the treatment of mild GDM during pregnancy and their children. Trained nurses measured the height and weight of the children at preschool visits in a state-wide surveillance program in the state of South Australia. The main outcome measure was age- and sex-specific BMI Z score based on standards of the International Obesity Task Force. RESULTS At birth, prevalence of macrosomia (birth weight ≥4,000 g) was 5.3% among the 94 children whose mothers were in the intervention group, and 21.9% among the 105 children in the routine care control group. At 4- to 5-years-old, mean (SD) BMI Z score was 0.49 (1.20) in intervention children and 0.41 (1.40) among controls. The difference between treatment groups was 0.08 (95% CI −0.29 to 0.44), an estimate minimally changed by adjustment for maternal race, parity, age, and socio-economic index (0.08 [−0.29 to 0.45]). Evaluating BMI ≥85th percentile rather than continuous BMI Z score gave similarly null results. CONCLUSIONS Although treatment of GDM substantially reduced macrosomia at birth, it did not result in a change in BMI at age 4- to 5-years-old. PMID:20150300

Examining the Association Between Body Mass Index and Weight Related Quality of Life in Black and White Women

PubMed Central

Ard, Jamy D.; Beasley, T. Mark; Fernandez, Jose R.; Howard, Virginia J.; Kolotkin, Ronnete L.; Crosby, Ross D.; Affuso, Olivia

2017-01-01

Obesity not only increases risk for morbidity/mortality, but also impacts the quality of life of obese individuals. In the United States, black women have the highest prevalence of obesity of any other group with approximately 80% of black women over age 20 having a body mass index (BMI) ≥25 kg/m2. We aimed to examine the association between BMI and quality of life in this high risk population compared to this association in white women, using the Impact of Weight on Quality of Life (IWQOL)-Lite questionnaire. Data from 172 black women (mean BMI= 35.7; age=40.5) and 171 white women (mean BMI= 35.5; age=40.4) were collected between 2000 and 2010 analyzed in 2010. The mean IWQOL-Lite total score was 81.6 for black women compared to 66.9 for white women, a statistically significant difference. Hierarchical linear regression models revealed a significant BMI-by-race interaction indicating that the relationship between BMI and IWQOL-Lite score was moderated by race. Our findings suggest notable differences in weight-related quality of life in black and white women. At similar BMIs, black women consistently reported better quality of life than white women on all IWQOL-Lite subscales. The greatest difference in IWQOL-Lite scores between black and white women was seen in the self-esteem subscale. Additional research is needed to understand how to incorporate the weight perspectives of black women into weight management messages and interventions. PMID:28286583

Abdominal fat distribution and its relationship to brain changes: the differential effects of age on cerebellar structure and function: a cross-sectional, exploratory study

PubMed Central

Raschpichler, Matthias; Straatman, Kees; Schroeter, Matthias Leopold; Arelin, Katrin; Schlögl, Haiko; Fritzsch, Dominik; Mende, Meinhard; Pampel, André; Böttcher, Yvonne; Stumvoll, Michael; Villringer, Arno; Mueller, Karsten

2013-01-01

Objectives To investigate whether the metabolically important visceral adipose tissue (VAT) relates differently to structural and functional brain changes in comparison with body weight measured as body mass index (BMI). Moreover, we aimed to investigate whether these effects change with age. Design Cross-sectional, exploratory. Setting University Clinic, Integrative Research and Treatment Centre. Participants We included 100 (mean BMI=26.0 kg/m², 42 women) out of 202 volunteers randomly invited by the city's registration office, subdivided into two age groups: young-to-mid-age (n=51, 20–45 years of age, mean BMI=24.9, 24 women) versus old (n=49, 65–70 years of age, mean BMI=27.0, 18 women). Main outcome measures VAT, BMI, subcutaneous abdominal adipose tissue, brain structure (grey matter density), functional brain architecture (eigenvector centrality, EC). Results We discovered a loss of cerebellar structure with increasing VAT in the younger participants, most significantly in regions involved in motor processing. This negative correlation disappeared in the elderly. Investigating functional brain architecture showed again inverse VAT–cerebellum correlations, whereas now regions involved in cognitive and emotional processing were significant. Although we detected similar results for EC using BMI, significant age interaction for both brain structure and functional architecture was only found using VAT. Conclusions Visceral adiposity is associated with cerebellar changes of both structure and function, whereas the regions involved contribute to motor, cognitive and emotional processes. Furthermore, these associations seem to be age dependent, with younger adults’ brains being adversely affected. PMID:23355665

Higher body mass index is associated with reduced posterior default mode connectivity in older adults.

PubMed

Beyer, Frauke; Kharabian Masouleh, Sharzhad; Huntenburg, Julia M; Lampe, Leonie; Luck, Tobias; Riedel-Heller, Steffi G; Loeffler, Markus; Schroeter, Matthias L; Stumvoll, Michael; Villringer, Arno; Witte, A Veronica

2017-04-11

Obesity is a complex neurobehavioral disorder that has been linked to changes in brain structure and function. However, the impact of obesity on functional connectivity and cognition in aging humans is largely unknown. Therefore, the association of body mass index (BMI), resting-state network connectivity, and cognitive performance in 712 healthy, well-characterized older adults of the Leipzig Research Center for Civilization Diseases (LIFE) cohort (60-80 years old, mean BMI 27.6 kg/m 2  ± 4.2 SD, main sample: n = 521, replication sample: n = 191) was determined. Statistical analyses included a multivariate model selection approach followed by univariate analyses to adjust for possible confounders. Results showed that a higher BMI was significantly associated with lower default mode functional connectivity in the posterior cingulate cortex and precuneus. The effect remained stable after controlling for age, sex, head motion, registration quality, cardiovascular, and genetic factors as well as in replication analyses. Lower functional connectivity in BMI-associated areas correlated with worse executive function. In addition, higher BMI correlated with stronger head motion. Using 3T neuroimaging in a large cohort of healthy older adults, independent negative associations of obesity and functional connectivity in the posterior default mode network were observed. In addition, a subtle link between lower resting-state connectivity in BMI-associated regions and cognitive function was found. The findings might indicate that obesity is associated with patterns of decreased default mode connectivity similar to those seen in populations at risk for Alzheimer's disease. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

The effect of cardiorespiratory fitness and obesity on cancer mortality in women and men.

PubMed

Evenson, Kelly R; Stevens, June; Cai, Jianwen; Thomas, Ratna; Thomas, Olivia

2003-02-01

The purpose of this study was to determine the independent and combined effects of cardiorespiratory fitness and obesity on all-cause cancer mortality for women and men. Using the Lipids Research Clinics Prevalence Study, we examined the relationship of fitness and obesity on cancer mortality among 2585 women and 2890 men followed from 1972-1976 to 1998. Cardiorespiratory fitness was measured using a treadmill test and obesity was assessed using body mass index (BMI) calculated from measured height and weight. Gender-specific hazard ratios (HR) were calculated from proportional hazard models, which included covariates for age, education, smoking, alcohol intake, Keys score, and menopause (women only). Adjusted cancer mortality was significantly lower in the most fit quintile relative to the other four quintiles for men (HR = 0.47; 95% CI, 0.27-0.81) but not for women (HR = 0.84; 95% CI, 0.52-1.36). Adjusted cancer mortality was significantly higher in the highest BMI quintile relative to the other four BMI quintiles for women (HR = 1.49; 95% CI, 1.06-2.09) but not for men (HR = 1.05; 95% CI, 0.77-1.43). Further adjustment for BMI on fitness and adjustment for fitness on BMI did not meaningfully change the HR. There were no significant interactions between fitness and obesity in predicting cancer mortality for either women or men. In this study, high fitness was a stronger predictor of cancer mortality in men, whereas high BMI was a stronger predictor of cancer mortality in women.

Randomized, double-blind, placebo-controlled trial of orlistat for weight loss in adolescents.

PubMed

Maahs, David; de Serna, Daniela Gonzalez; Kolotkin, Ronette L; Ralston, Shawn; Sandate, Jeffrey; Qualls, Clifford; Schade, David S

2006-01-01

To evaluate the efficacy of orlistat to enhance weight loss in obese adolescents. The study was a 6-month randomized, double-blind, placebo-controlled trial to compare the effects of orlistat (120 mg orally 3 times a day) and placebo on reduction of body mass index (BMI). Forty adolescents between 14 and 18 years of age with a mean BMI of 40 kg/m2 entered the protocol between December 2002 and February 2003. Study subjects stayed overnight in the General Clinical Research Center, during which dietary records were reviewed and lifestyle recommendations were given. The study participants received either orlistat (120 mg orally 3 times a day) or placebo and were assessed monthly for 6 months. At 0, 3, and 6 months, fasting laboratory tests were performed. The primary end point was the change in BMI from baseline to 6 months. Secondary outcomes included changes in weight, lean body mass, and results of blood chemistry studies. No statistically significant difference was noted between the 2 study groups for decrease in BMI from baseline to 6 months (P = 0.39). The decrease in BMI within the orlistat group (-1.3 +/- 1.6 kg/m2; P = 0.04) and within the placebo group (-0.8 +/- 3.0 kg/m2; P = 0.02), however, was statistically significant. Laboratory measurements did not differ between the 2 groups. In comparison with the placebo group, the orlistat group had increased adverse events, primarily gastrointestinal symptoms and findings. In this study of obese adolescents, orlistat did not significantly reduce BMI in comparison with placebo at 6 months.

Family meals and body mass index among adolescents: effects of gender.

PubMed

Goldfield, Gary S; Murray, Marisa A; Buchholz, Annick; Henderson, Katherine; Obeid, Nicole; Kukaswadia, Atif; Flament, Martine F

2011-08-01

Family meals have been identified as a protective factor against obesity among youth. However, gender specificities with respect to the relationship between the frequency of family meals and body mass index (BMI) have not been investigated. The purpose of this study was to examine the relationship between the frequency of family meals and BMI in male and female adolescents, while controlling for potential confounding factors associated with BMI, such as parental education, adolescent's age, and snack-food eating. Research participants were 734 male and 1030 female students (mean age, 14.12 years, SD = 1.62) recruited from middle schools and high schools in the capital region of Canada. Participants completed validated, self-report measures to assess the frequency of family meals and the risk factors associated with increased BMI, which was derived from objective measures of height and weight. After controlling for proposed confounding variables, a higher frequency of family meals was associated with lower BMI in females, but not in males. A Z-transformation test of the homogeneity of adjusted correlation coefficients showed a significant trend (p = 0.06), indicating that the relationship between family meals and BMI is stronger in females than males, consistent with our regression analyses. Our findings suggest that eating together as a family may be a protective factor against obesity in female adolescents, but not in male adolescents. Findings from this study have important implications for parents and health care practitioners advocating for more frequent family meals as part of a comprehensive obesity prevention and treatment program for female adolescents.

Percentage body fat ranges associated with metabolic syndrome risk: results based on the third National Health and Nutrition Examination Survey (1988-1994).

PubMed

Zhu, Shankuan; Wang, ZiMian; Shen, Wei; Heymsfield, Steven B; Heshka, Stanley

2003-08-01

Increasing attention has focused on the association between body fatness and related metabolic risk factors. The quantitative link between percentage body fat (%BF) and the risk of metabolic syndrome is unknown. The objectives were to determine the risk [odds ratios (ORs)] of metabolic syndrome based on %BF in black and white men and women in the United States and to provide corresponding ranges of %BF associated with a risk equivalent to body mass index (BMI; in kg/m(2)). The subjects were participants in the third National Health and Nutrition Examination Survey and were divided into those with and without the metabolic syndrome. OR equations were derived from logistic regression models for %BF and BMI, with the 25th percentile in the study population as the reference. Ranges were developed by associating %BF with the equivalent risk of metabolic syndrome based on established BMI cutoffs. Four sets (men, women, black, and white) of OR curves were generated for %BF and for BMI by using data from 8259 adults. The ORs for metabolic syndrome were lower in blacks than in whites at any given %BF or BMI. The developed cutoffs for %BF differed between men and women but showed only small race and age effects. A simplified set of sex-specific %BF ranges for the risk of metabolic syndrome were developed. The risk of metabolic syndrome can be established from measured %BF by using either the developed OR curves or %BF thresholds at traditional BMI cutoffs. This information should prove useful in both clinical and research settings.

Changes in abdominal obesity in Chilean university students stratified by body mass index.

PubMed

Cossio-Bolaños, Marco; Vilchez-Avaca, Catalina; Contreras-Mellado, Victor; Andruske, Cynthia Lee; Gómez-Campos, Rossana

2016-01-13

Studies based on Body Mass Index (BMI) and waist circumference (WC) are generally used to examine the prevalence and tendency of overweight and obesity. These studies help determine the socioeconomic development of a country and improve public health policies. Therefore, the goal of this research was to determine the trend of change in abdominal obesity of Chilean university students according to the Body Mass Index (BMI) measured in intervals of three and six years. For this study, a total of 1598 students of both sexes ranging in age from 18 to 26 from a Chilean university were evaluated. Students were assessed commencing in 2007 (372 males and 315 females), 2010 (250 males and 330 females), and ending in 2013 (153 males and 178 females). During the three transversal assessments, weight, height, and waist circumference were evaluated. BMI was calculated for both sexes. No significant differences were found in age and BMI during the three years evaluated (2007, 2010, and 2013). In 2013, waist circumference (WC) increased significantly (p < 0.001 for both sexes). Moreover, in 2013, in all the percentiles evaluated, high values of WC were compared in relation to previous years. Furthermore, in 2013, in all four BMI categories (underweight, normal, overweight, and obese), the university students showed significant increases in WC (Females: p = 0.004; Males: p = 0.035) whereas in 2007 and 2010, the values remained relatively stable. BMI remained constant during 2007, 2010, and 2013. However, the university students of both sexes showed greater risk of abdominal obesity as a result of increased WC in 2013.

Body mass index and alcohol consumption: family history of alcoholism as a moderator.

PubMed

Gearhardt, Ashley N; Corbin, William R

2009-06-01

Recent research suggests that excess food consumption may be conceptualized as an addictive behavior. Much of the evidence comes from neurobiological similarities between drug and food consumption. In addition, an inverse relation between alcohol consumption and body mass index (BMI) has been observed. Previous research has hypothesized that this inverse relation is attributable to competition between food and alcohol for similar neurotransmitter receptors. The current study explored this neurobiological hypothesis further by examining the influence of an indicator of biological risk associated with alcohol problems (family history of alcoholism) on the relationship between alcohol and food intake. Data from 37,259 participants in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) were included in the study. BMI, family history of alcoholism, gender, and race/ethnicity were assessed as predictors of typical drinking frequency and estimated blood alcohol concentration (BAC). An inverse relationship between alcohol consumption and BMI was demonstrated. An attenuation of family history effects on drinking behavior was evident for obese compared to nonobese participants. The results suggest a neurobiological link between alcohol use and food consumption, consistent with theories characterizing excess food consumption as an addictive behavior. Copyright (c) 2009 APA, all rights reserved.

Chronic insufficient sleep and diet quality: Contributors to childhood obesity.

PubMed

Cespedes, Elizabeth M; Hu, Frank B; Redline, Susan; Rosner, Bernard; Gillman, Matthew W; Rifas-Shiman, Sheryl L; Taveras, Elsie M

2016-01-01

To examine associations of chronic insufficient sleep with diet and whether diet explains the sleep-adiposity relationship. In Project Viva, 1,046 parents reported children's sleep duration at 6 m and annually until midchildhood (7 y). The main exposure was a sleep curtailment score (6 m-7 y) ranging from 0 (maximal curtailment) to 13 (adequate sleep). In mid-childhood, parents reported children's diet; researchers measured height/weight. Multivariable linear regression assessed associations of sleep with diet (Youth Healthy Eating Index [YHEI]); sleep with BMI z-score adjusting for YHEI; and, secondarily, joint associations of sleep and YHEI with BMI. Mean (SD) sleep and YHEI scores were 10.21 (2.71) and 58.76 (10.37). Longer sleep duration was associated with higher YHEI in mid-childhood (0.59 points/unit sleep score; 95% CI: 0.32, 0.86). Although higher YHEI was associated with lower BMI z-score (-0.07 units/10-point increase; 95% CI: -0.13, -0.01), adjustment for YHEI did not attenuate sleep-BMI associations. Children with sleep and YHEI scores below the median (<11 and <60) had BMI z-scores 0.34 units higher (95% CI: 0.16, 0.51) than children with sleep and YHEI scores above the median. While parent-reported diet did not explain inverse associations of sleep with adiposity, both sufficient sleep and high-quality diets are important to obesity prevention. © 2015 The Obesity Society.

[DAILY AND ABNORMAL EATING BEHAVIORS IN A COMMUNITY SAMPLE OF CHILEAN ADULTS].

PubMed

Oda-Montecinos, Camila; Saldaña, Carmina; Andrés Valle, Ana

2015-08-01

this research aimed to characterize the daily eating behavior in a sample of Chilean adults according to their Body Mass Index (BMI) and gender and to analyze the possible links between these variables and abnormal eating behaviors. 657 participants (437 women and 220 men, age range 18-64 years) were evaluated with a battery of self-administered questionnaires. Mean BMI was 25.50 kg/m2 (women 24.96 kg/m2, men 26.58 kg/m2), being significantly higher the mean of BMI in the men group, being the BMI mean of the total sample and that of the male group in the overweight range. participants with overweight (BMI ≥ 25 kg/m2), in contrast with normal-weight group, tended to do more frequently the following behaviors: skip meals, follow a diet, eat less homemade food, eat faster and in greater quantities, in addition to do a greater number of abnormal eating behaviors of various kinds and to rate significantly higher in clinical scales that evaluated eating restraint and overeating. Men showed significantly more eating behaviors linked with overeating, and women performed more behaviors related with eating restraint and emotional eating. the results suggest that, besides "what" people eat, "how" people eat, in terms of specific behaviors, may contribute to the rapid increase of overweight in Chilean population. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Health and Pleasure in Consumers' Dietary Food Choices: Individual Differences in the Brain's Value System

PubMed Central

Petit, Olivia; Merunka, Dwight; Anton, Jean-Luc; Nazarian, Bruno; Spence, Charles; Cheok, Adrian David; Raccah, Denis; Oullier, Olivier

2016-01-01

Taking into account how people value the healthiness and tastiness of food at both the behavioral and brain levels may help to better understand and address overweight and obesity-related issues. Here, we investigate whether brain activity in those areas involved in self-control may increase significantly when individuals with a high body-mass index (BMI) focus their attention on the taste rather than on the health benefits related to healthy food choices. Under such conditions, BMI is positively correlated with both the neural responses to healthy food choices in those brain areas associated with gustation (insula), reward value (orbitofrontal cortex), and self-control (inferior frontal gyrus), and with the percent of healthy food choices. By contrast, when attention is directed towards health benefits, BMI is negatively correlated with neural activity in gustatory and reward-related brain areas (insula, inferior frontal operculum). Taken together, these findings suggest that those individuals with a high BMI do not necessarily have reduced capacities for self-control but that they may be facilitated by external cues that direct their attention toward the tastiness of healthy food. Thus, promoting the taste of healthy food in communication campaigns and/or food packaging may lead to more successful self-control and healthy food behaviors for consumers with a higher BMI, an issue which needs to be further researched. PMID:27428267

Examining weight concern and delay discounting in adolescent females.

PubMed

Thamotharan, Sneha; Lange, Krista; Ramos, Ashley; Fields, Sherecce

2016-04-01

Pediatric obesity is a growing public health concern that contributes to high rates of negative long-term physical and mental health outcomes. Research focused on identifying risk for pediatric obesity has linked delay discounting, or an inclination for immediate rewards, as well as weight concern to individuals with greater Body Mass Index (BMI). The current study seeks to fill a void in the literature by examining how these two variables interact to promote higher BMI in female adolescents. Adolescent (n=60) females between the ages of 13-19years (mage=17.45, SD=1.74) of age completed the Eating Disorder Examination Questionnaire (EDE-Q) and the Delay Discounting Questionnaire. A mediation model examined whether delay discounting accounted for the relationship between weight concern and BMI. Results indicate that in the current study weight concern was negatively related to delay discounting and delay discounting was negatively related to BMI. The overall model revealed that a partial mediation occurred [b=1.28, t(60)=4.92, p<0.01]. These results suggest that while impulsivity is an important factor to consider, other constructs may also be influential in how weight concerns contribute to greater BMI. Nevertheless, the results indicate that prevention and interventions should identify females with high levels of both weight concern and impulsivity as an increased risk for experiencing pediatric obesity and long-term negative health outcomes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Alpha-lipoic acid (ALA) as a supplementation for weight loss: results from a meta-analysis of randomized controlled trials.

PubMed

Kucukgoncu, S; Zhou, E; Lucas, K B; Tek, C

2017-05-01

Obesity is associated with significant morbidity and mortality rates. Even modest weight loss may be associated with health benefits. Alpha-lipoic acid (ALA) is a naturally occurring antioxidant. Studies have suggested anti-obesity properties of ALA; however, results are inconsistent. The purpose of this study is to conduct a meta-analysis of the effect of ALA on weight and body mass index (BMI). A comprehensive, systematic literature search identified 10 articles on randomized, double-blind, placebo-controlled studies involving ALA. We conducted a meta-analysis of mean weight and BMI change differences between ALA and placebo treatment groups. Alpha-lipoic acid treatment coincided with a statistically significant 1.27 kg (confidence interval = 0.25 to 2.29) greater mean weight loss compared with the placebo group. A significant overall mean BMI difference of -0.43 kg/ m 2 (confidence interval = -0.82 to -0.03) was found between the ALA and placebo groups. Meta-regression analysis showed no significance in ALA dose on BMI and weight changes. Study duration significantly affected BMI change, but not weight change. Alpha-lipoic acid treatment showed small, yet significant short-term weight loss compared with placebo. Further research is needed to examine the effect of different doses and the long-term benefits of ALA on weight management. © 2017 World Obesity Federation.

Health and Pleasure in Consumers' Dietary Food Choices: Individual Differences in the Brain's Value System.

PubMed

Petit, Olivia; Merunka, Dwight; Anton, Jean-Luc; Nazarian, Bruno; Spence, Charles; Cheok, Adrian David; Raccah, Denis; Oullier, Olivier

2016-01-01

Taking into account how people value the healthiness and tastiness of food at both the behavioral and brain levels may help to better understand and address overweight and obesity-related issues. Here, we investigate whether brain activity in those areas involved in self-control may increase significantly when individuals with a high body-mass index (BMI) focus their attention on the taste rather than on the health benefits related to healthy food choices. Under such conditions, BMI is positively correlated with both the neural responses to healthy food choices in those brain areas associated with gustation (insula), reward value (orbitofrontal cortex), and self-control (inferior frontal gyrus), and with the percent of healthy food choices. By contrast, when attention is directed towards health benefits, BMI is negatively correlated with neural activity in gustatory and reward-related brain areas (insula, inferior frontal operculum). Taken together, these findings suggest that those individuals with a high BMI do not necessarily have reduced capacities for self-control but that they may be facilitated by external cues that direct their attention toward the tastiness of healthy food. Thus, promoting the taste of healthy food in communication campaigns and/or food packaging may lead to more successful self-control and healthy food behaviors for consumers with a higher BMI, an issue which needs to be further researched.

Multi-electrode stimulation in somatosensory cortex increases probability of detection

NASA Astrophysics Data System (ADS)

Zaaimi, Boubker; Ruiz-Torres, Ricardo; Solla, Sara A.; Miller, Lee E.

2013-10-01

Objective. Brain machine interfaces (BMIs) that decode control signals from motor cortex have developed tremendously in the past decade, but virtually all rely exclusively on vision to provide feedback. There is now increasing interest in developing an afferent interface to replace natural somatosensation, much as the cochlear implant has done for the sense of hearing. Preliminary experiments toward a somatosensory neuroprosthesis have mostly addressed the sense of touch, but proprioception, the sense of limb position and movement, is also critical for the control of movement. However, proprioceptive areas of cortex lack the precise somatotopy of tactile areas. We showed previously that there is only a weak tendency for neighboring neurons in area 2 to signal similar directions of hand movement. Consequently, stimulation with the relatively large currents used in many studies is likely to activate a rather heterogeneous set of neurons. Approach. Here, we have compared the effect of single-electrode stimulation at subthreshold levels to the effect of stimulating as many as seven electrodes in combination. Main results. We found a mean enhancement in the sensitivity to the stimulus (d‧) of 0.17 for pairs compared to individual electrodes (an increase of roughly 30%), and an increase of 2.5 for groups of seven electrodes (260%). Significance. We propose that a proprioceptive interface made up of several hundred electrodes may yield safer, more effective sensation than a BMI using fewer electrodes and larger currents.

Disparities in obesity among rural and urban residents in a health disparate region.

PubMed

Hill, Jennie L; You, Wen; Zoellner, Jamie M

2014-10-08

The burden of obesity and obesity-related conditions is not borne equally and disparities in prevalence are well documented for low-income, minority and rural adults in the United States. The current literature on rural versus urban disparities is largely derived from national surveillance data which may not reflect regional nuances. There is little practical research that supports the reality of local service providers such as county health departments that may serve both urban and rural residents in a given area. Conducted through a community-academic partnership, the primary aim of this study is to quantify the current levels of obesity (BMI), fruit and vegetable (FV) intake and physical activity (PA) in a predominately rural health disparate region. Secondary aims are to determine if a gradient exists within the region in which rural residents have poorer outcomes on these indicators compared to urban residents. Conducted as part of a larger ongoing community-based participatory research (CBPR) initiative, data were gathered through a random digit dial telephone survey using previously validated measures (n = 784). Linear, logistic and quantile regression models are used to determine if residency (i.e. rural, urban) predicts outcomes of FV intake, PA and BMI. The majority (72%) of respondents were overweight (BMI = 29 ± 6 kg/m2), with 29% being obese. Only 9% of residents met recommendations for FV intake and 38% met recommendations for PA. Statistically significant gradients between urban and rural and race exist at the upper end of the BMI distribution. In other words, the severity of obesity is worse among black compared to white and for urban residents compared to rural residents. These results will be used by the community-academic partnership to guide the development of culturally relevant and sustainable interventions to increase PA, increase FV intake and reduce obesity within this health disparate region. In particular, local stakeholders may wish to address disparities in BMI by allocating resources to the vulnerable groups identified.

The future burden of obesity-related diseases in the 53 WHO European-Region countries and the impact of effective interventions: a modelling study

PubMed Central

Webber, Laura; Divajeva, Diana; Marsh, Tim; McPherson, Klim; Brown, Martin; Galea, Gauden; Breda, Joao

2014-01-01

Objective Non-communicable diseases (NCDs) are the biggest cause of death in Europe putting an unsustainable burden on already struggling health systems. Increases in obesity are a major cause of NCDs. This paper projects the future burden of coronary heart disease (CHD), stroke, type 2 diabetes and seven cancers by 2030 in 53 WHO European Region countries based on current and past body mass index (BMI) trends. It also tests the impact of obesity interventions on the future disease burden. Setting and participants Secondary data analysis of country-specific epidemiological data using a microsimulation modelling process. Interventions The effect of three hypothetical scenarios on the future burden of disease in 2030 was tested: baseline scenario, BMI trends go unchecked; intervention 1, population BMI decreases by 1%; intervention 2, BMI decreases by 5%. Primary and secondary outcome measures Quantifying the future burden of major NCDs and the impact of interventions on this future disease burden. Results By 2030 in the whole of the European region, the prevalence of diabetes, CHD and stroke and cancers was projected to reach an average of 3990, 4672 and 2046 cases/100 000, respectively. The highest prevalence of diabetes was predicted in Slovakia (10 870), CHD and stroke—in Greece (11 292) and cancers—in Finland (5615 cases/100 000). A 5% fall in population BMI was projected to significantly reduce cumulative incidence of diseases. The largest reduction in diabetes and CHD and stroke was observed in Slovakia (3054 and 3369 cases/100 000, respectively), and in cancers was predicted in Germany (331/100 000). Conclusions Modelling future disease trends is a useful tool for policymakers so that they can allocate resources effectively and implement policies to prevent NCDs. Future research will allow real policy interventions to be tested; however, better surveillance data on NCDs and their risk factors are essential for research and policy. PMID:25063459

Validity of self-measured waist and hip circumferences: results from a community study in Malaysia.

PubMed

Reidpath, Daniel D; Cheah, Julius Chee-Ho; Lam, Fui-Ching; Yasin, Shahjahan; Soyiri, Ireneous; Allotey, Pascale

2013-10-05

Measures of central adiposity are better predictors of adverse health events than BMI. Nonetheless, BMI is more widely used in health research. One reason for this may be the limited research supporting the self-measurement of waist and hip circumference. The lack of validity studies is particularly acute in Asia. The main objective was to establish the validity of self-measurement of waist and hip circumference in a community setting and the correlation of those measures with BMI, blood pressure, and blood glucose levels. A community based, cross-sectional survey. A "healthy living expo" at a shopping mall in a rural town on peninsular Malaysia One hundred and thirty six (136) individuals volunteered to participate in the study, 125 of whom met the inclusion criteria. The ethnic distribution of the participants was 80% Chinese, 17% Malay and 3% Indian. Most participants were female (60%), with participants' ages ranging from 18 to 78 years (mean, 47.2). Self and assisted measurements of waist and hip were taken. Blood pressure, non-fasting blood glucose, height, and weight were also measured. Bland Altman plots and Lin's concordance coefficient were used to measure agreement between self and assisted measures. Pearson's correlation was used to examine the association of self and assisted measures with blood pressure, blood glucose, and BMI. There was a downwards bias in self measured waist (-0.81 cm) and hip (-1 cm) circumferences compared with assisted measures. The concordance for the self and assisted measures of waist, hip and the ratio of the two were, respectively, .96, .93 , and .84. The correlation between measures of central adiposity and BMI, blood pressure and blood glucose were similar for self and assisted measures. The results provide additional support for the use of self-measurement of waist and hip circumference studies of central adiposity, but is limited by the specificity of the setting.

[Evaluation of nutrition mode and nutritional status and pro health education of children during the period of pubertal spurt in the city of Szczecin].

PubMed

Goluch-Koniuszy, Zuzanna; Friedrich, Mariola; Radziszewska, Magdalena

2009-01-01

This research was aimed at evaluation of the method of nutrition and the state of nutrition in the children aged 13 during the period of pubertal spurt who had their body mass, body height and waist measurement defined. These values led to calculation of BMI, WC, and WHtR indicators, which were related to centile distribution of children from Warszawa and Lódź. Only in 63.6% of girls and 68.9% of boys from Szczecin schools the value of BMI was proper. The problem of accumulation of fat tissue (WC > or = 90 c) around the waist refers to nearly 14% of girls and 9.4% of boys. The value of the indicator WHtR > or = 90 c was found in 11% of the children under research. Children with overweight (BMI 90-97 c) and obesity (BMI > or = 97 c) were selected based on the value of BMI indicator. Their menus of three chosen at random weekdays were obtained. Analysis of the nutrition method of children with overweight and obesity showed low energy value of the diet, general protein, complex carbohydrates, cellulose, mineral components (Ca, Mg, Fe, Cu, Zn), A, E (girls), C (boys), group B vitamins and also liquids deficiency. The children have undergone a special pro health education in the form of "live" workshops and 3 months after an evaluation inquiry was conducted to assess the effects of the workshops. The analysis of the evaluation inquiry showed that the children have included in their diet breakfasts and afternoon snacks and to their main meal menus whole wheat products, larger quantity of vegetables, fruit and water. It has been also established that sweets, meals of fast food types, chips, pizzy and energizing drinks have been limited.

BMI and BMI SDS in childhood: annual increments and conditional change.

PubMed

Brannsether, Bente; Eide, Geir Egil; Roelants, Mathieu; Bjerknes, Robert; Júlíusson, Pétur Benedikt

2017-02-01

Background Early detection of abnormal weight gain in childhood may be important for preventive purposes. It is still debated which annual changes in BMI should warrant attention. Aim To analyse 1-year increments of Body Mass Index (BMI) and standardised BMI (BMI SDS) in childhood and explore conditional change in BMI SDS as an alternative method to evaluate 1-year changes in BMI. Subjects and methods The distributions of 1-year increments of BMI (kg/m 2 ) and BMI SDS are summarised by percentiles. Differences according to sex, age, height, weight, initial BMI and weight status on the BMI and BMI SDS increments were assessed with multiple linear regression. Conditional change in BMI SDS was based on the correlation between annual BMI measurements converted to SDS. Results BMI increments depended significantly on sex, height, weight and initial BMI. Changes in BMI SDS depended significantly only on the initial BMI SDS. The distribution of conditional change in BMI SDS using a two-correlation model was close to normal (mean = 0.11, SD = 1.02, n = 1167), with 3.2% (2.3-4.4%) of the observations below -2 SD and 2.8% (2.0-4.0%) above +2 SD. Conclusion Conditional change in BMI SDS can be used to detect unexpected large changes in BMI SDS. Although this method requires the use of a computer, it may be clinically useful to detect aberrant weight development.

Development of a simulated smart pump interface.

PubMed

Elias, Beth L; Moss, Jacqueline A; Shih, Alan; Dillavou, Marcus

2014-01-01

Medical device user interfaces are increasingly complex, resulting in a need for evaluation in clinicallyaccurate settings. Simulation of these interfaces can allow for evaluation, training, and use for research without the risk of harming patients and with a significant cost reduction over using the actual medical devices. This pilot project was phase 1 of a study to define and evaluate a methodology for development of simulated medical device interface technology to be used for education, device development, and research. Digital video and audio recordings of interface interactions were analyzed to develop a model of a smart intravenous medication infusion pump user interface. This model was used to program a high-fidelity simulated smart intravenous medication infusion pump user interface on an inexpensive netbook platform.

Smoking Cessation and Changes in Body Mass Index: Findings From the First Randomized Cessation Trial in a Low-Income Country Setting.

PubMed

Ben Taleb, Ziyad; Ward, Kenneth D; Asfar, Taghrid; Jaber, Rana; Bahelah, Raed; Maziak, Wasim

2017-03-01

In high-income countries, quitting cigarette smoking is associated with weight gain, which can reduce motivation to abstain. Whether smoking cessation is associated with weight gain in a low-income country context has never been investigated. We aimed to determine the post-cessation changes in body mass index (BMI) and its predictors among smokers who received a smoking cessation intervention in a low-income country setting. We performed post hoc analyses of data from 269 smokers who participated in a two-group, parallel-arm, double-blind, placebo-controlled randomized trial of combined nicotine replacement therapy (NRT) and behavioral counseling in primary care clinics in Aleppo, Syria. We used generalized estimating equation modeling to identify predictors of changes in BMI at 6 weeks and 6- and 12-month follow-ups after quit date. The mean pre-cessation BMI of the sample was 27.9kg/m2 (SD = 5.2). Over 12 months of follow-up, BMI of smoking abstainers averaged 1.8 BMI units (approximately 4.8kg) greater than non-abstainers (p = .012). Throughout the study, greater BMI was associated with being female (p = .048), reporting smoking to control weight (p < .001) and having previously failed to quit due to weight gain (p = .036). Similar to findings from high-income countries, smoking cessation in Syria is associated with weight gain, particularly among women and those who have weight concerns prior to quitting. This group of smokers may benefit from tailored cessation interventions with integrated body weight management elements that take into consideration the prevailing local and cultural influences on diet and levels of physical activity. This study provides the first evidence regarding post-cessation changes in BMI among smokers who attempt to quit in a low-income country setting. Our findings advance knowledge regarding post-cessation weight gain and offers insight for researchers and clinicians to identify smokers at higher risk of post-cessation weight gain. This information will help in delivering interventions that take into account the prevailing cultural influence on diet and physical activity and will ultimately help in designing future tailored cessation programs in Syria and other low-income countries with similar cultural background and level of development. © The Author 2016. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Research the mobile phone operation interfaces for vision-impairment.

PubMed

Yao, Yen-Ting; Leung, Cherng-Yee

2012-01-01

Due to the vision-impaired users commonly having difficulty with mobile-phone function operations and adaption any manufacturer's user interface design, the goals for this research are established for evaluating how to improve for them the function operation convenience and user interfaces of either mobile phones or electronic appliances in the market currently. After applying collecting back 30 effective questionnaires from 30 vision-impairment, the comments have been concluded from this research include: (1) All mobile phone manufactures commonly ignorant of the vision-impairment difficulty with operating mobile phone user interfaces; (2) The vision-impairment preferential with audio alert signals; (3) The vision-impairment incapable of mobile-phone procurement independently unless with assistance from others; (4) Preferential with adding touch-usage interface design by the vision-impairment; in contrast with the least requirement for such functions as braille, enlarging keystroke size and diversifying-function control panel. With exploring the vision-impairment's necessary improvements and obstacles for mobile phone interface operation, this research is established with goals for offering reference possibly applied in electronic appliance design and . Hopefully, the analysis results of this research could be used as data references for designing electronic and high-tech products and promoting more usage convenience for those vision-impaired.

Indigenous Research: Three Researchers Reflect on Their Experiences at the Interface

ERIC Educational Resources Information Center

Minniecon, Deanne; Franks, Naomi; Heffernan, Maree

2007-01-01

Utilising Nakata's (2007) description of the "cultural interface", two Indigenous researchers and one non-Indigenous researcher examine their development of Indigenous research in and with Aboriginal and Torres Strait Islander communities conducted from within an institution of higher education. The authors reflect on their experiences in…

Multisession, noninvasive closed-loop neuroprosthetic control of grasping by upper limb amputees.

PubMed

Agashe, H A; Paek, A Y; Contreras-Vidal, J L

2016-01-01

Upper limb amputation results in a severe reduction in the quality of life of affected individuals due to their inability to easily perform activities of daily living. Brain-machine interfaces (BMIs) that translate grasping intent from the brain's neural activity into prosthetic control may increase the level of natural control currently available in myoelectric prostheses. Current BMI techniques demonstrate accurate arm position and single degree-of-freedom grasp control but are invasive and require daily recalibration. In this study we tested if transradial amputees (A1 and A2) could control grasp preshaping in a prosthetic device using a noninvasive electroencephalography (EEG)-based closed-loop BMI system. Participants attempted to grasp presented objects by controlling two grasping synergies, in 12 sessions performed over 5 weeks. Prior to closed-loop control, the first six sessions included a decoder calibration phase using action observation by the participants; thereafter, the decoder was fixed to examine neuroprosthetic performance in the absence of decoder recalibration. Ability of participants to control the prosthetic was measured by the success rate of grasping; ie, the percentage of trials within a session in which presented objects were successfully grasped. Participant A1 maintained a steady success rate (63±3%) across sessions (significantly above chance [41±5%] for 11 sessions). Participant A2, who was under the influence of pharmacological treatment for depression, hormone imbalance, pain management (for phantom pain as well as shoulder joint inflammation), and drug dependence, achieved a success rate of 32±2% across sessions (significantly above chance [27±5%] in only two sessions). EEG signal quality was stable across sessions, but the decoders created during the first six sessions showed variation, indicating EEG features relevant to decoding at a smaller timescale (100ms) may not be stable. Overall, our results show that (a) an EEG-based BMI for grasping is a feasible strategy for further investigation of prosthetic control by amputees, and (b) factors that may affect brain activity such as medication need further examination to improve accuracy and stability of BMI performance. © 2016 Elsevier B.V. All rights reserved.

A brain-computer interface for potential non-verbal facial communication based on EEG signals related to specific emotions

PubMed Central

Kashihara, Koji

2014-01-01

Unlike assistive technology for verbal communication, the brain-machine or brain-computer interface (BMI/BCI) has not been established as a non-verbal communication tool for amyotrophic lateral sclerosis (ALS) patients. Face-to-face communication enables access to rich emotional information, but individuals suffering from neurological disorders, such as ALS and autism, may not express their emotions or communicate their negative feelings. Although emotions may be inferred by looking at facial expressions, emotional prediction for neutral faces necessitates advanced judgment. The process that underlies brain neuronal responses to neutral faces and causes emotional changes remains unknown. To address this problem, therefore, this study attempted to decode conditioned emotional reactions to neutral face stimuli. This direction was motivated by the assumption that if electroencephalogram (EEG) signals can be used to detect patients' emotional responses to specific inexpressive faces, the results could be incorporated into the design and development of BMI/BCI-based non-verbal communication tools. To these ends, this study investigated how a neutral face associated with a negative emotion modulates rapid central responses in face processing and then identified cortical activities. The conditioned neutral face-triggered event-related potentials that originated from the posterior temporal lobe statistically significantly changed during late face processing (600–700 ms) after stimulus, rather than in early face processing activities, such as P1 and N170 responses. Source localization revealed that the conditioned neutral faces increased activity in the right fusiform gyrus (FG). This study also developed an efficient method for detecting implicit negative emotional responses to specific faces by using EEG signals. A classification method based on a support vector machine enables the easy classification of neutral faces that trigger specific individual emotions. In accordance with this classification, a face on a computer morphs into a sad or displeased countenance. The proposed method could be incorporated as a part of non-verbal communication tools to enable emotional expression. PMID:25206321

A supplementary system for a brain-machine interface based on jaw artifacts for the bidimensional control of a robotic arm.

PubMed

Costa, Álvaro; Hortal, Enrique; Iáñez, Eduardo; Azorín, José M

2014-01-01

Non-invasive Brain-Machine Interfaces (BMIs) are being used more and more these days to design systems focused on helping people with motor disabilities. Spontaneous BMIs translate user's brain signals into commands to control devices. On these systems, by and large, 2 different mental tasks can be detected with enough accuracy. However, a large training time is required and the system needs to be adjusted on each session. This paper presents a supplementary system that employs BMI sensors, allowing the use of 2 systems (the BMI system and the supplementary system) with the same data acquisition device. This supplementary system is designed to control a robotic arm in two dimensions using electromyographical (EMG) signals extracted from the electroencephalographical (EEG) recordings. These signals are voluntarily produced by users clenching their jaws. EEG signals (with EMG contributions) were registered and analyzed to obtain the electrodes and the range of frequencies which provide the best classification results for 5 different clenching tasks. A training stage, based on the 2-dimensional control of a cursor, was designed and used by the volunteers to get used to this control. Afterwards, the control was extrapolated to a robotic arm in a 2-dimensional workspace. Although the training performed by volunteers requires 70 minutes, the final results suggest that in a shorter period of time (45 min), users should be able to control the robotic arm in 2 dimensions with their jaws. The designed system is compared with a similar 2-dimensional system based on spontaneous BMIs, and our system shows faster and more accurate performance. This is due to the nature of the control signals. Brain potentials are much more difficult to control than the electromyographical signals produced by jaw clenches. Additionally, the presented system also shows an improvement in the results compared with an electrooculographic system in a similar environment.

A Supplementary System for a Brain-Machine Interface Based on Jaw Artifacts for the Bidimensional Control of a Robotic Arm

PubMed Central

Costa, Álvaro; Hortal, Enrique; Iáñez, Eduardo; Azorín, José M.

2014-01-01

Non-invasive Brain-Machine Interfaces (BMIs) are being used more and more these days to design systems focused on helping people with motor disabilities. Spontaneous BMIs translate user's brain signals into commands to control devices. On these systems, by and large, 2 different mental tasks can be detected with enough accuracy. However, a large training time is required and the system needs to be adjusted on each session. This paper presents a supplementary system that employs BMI sensors, allowing the use of 2 systems (the BMI system and the supplementary system) with the same data acquisition device. This supplementary system is designed to control a robotic arm in two dimensions using electromyographical (EMG) signals extracted from the electroencephalographical (EEG) recordings. These signals are voluntarily produced by users clenching their jaws. EEG signals (with EMG contributions) were registered and analyzed to obtain the electrodes and the range of frequencies which provide the best classification results for 5 different clenching tasks. A training stage, based on the 2-dimensional control of a cursor, was designed and used by the volunteers to get used to this control. Afterwards, the control was extrapolated to a robotic arm in a 2-dimensional workspace. Although the training performed by volunteers requires 70 minutes, the final results suggest that in a shorter period of time (45 min), users should be able to control the robotic arm in 2 dimensions with their jaws. The designed system is compared with a similar 2-dimensional system based on spontaneous BMIs, and our system shows faster and more accurate performance. This is due to the nature of the control signals. Brain potentials are much more difficult to control than the electromyographical signals produced by jaw clenches. Additionally, the presented system also shows an improvement in the results compared with an electrooculographic system in a similar environment. PMID:25390372

A brain-computer interface for potential non-verbal facial communication based on EEG signals related to specific emotions.

PubMed

Kashihara, Koji

2014-01-01

Unlike assistive technology for verbal communication, the brain-machine or brain-computer interface (BMI/BCI) has not been established as a non-verbal communication tool for amyotrophic lateral sclerosis (ALS) patients. Face-to-face communication enables access to rich emotional information, but individuals suffering from neurological disorders, such as ALS and autism, may not express their emotions or communicate their negative feelings. Although emotions may be inferred by looking at facial expressions, emotional prediction for neutral faces necessitates advanced judgment. The process that underlies brain neuronal responses to neutral faces and causes emotional changes remains unknown. To address this problem, therefore, this study attempted to decode conditioned emotional reactions to neutral face stimuli. This direction was motivated by the assumption that if electroencephalogram (EEG) signals can be used to detect patients' emotional responses to specific inexpressive faces, the results could be incorporated into the design and development of BMI/BCI-based non-verbal communication tools. To these ends, this study investigated how a neutral face associated with a negative emotion modulates rapid central responses in face processing and then identified cortical activities. The conditioned neutral face-triggered event-related potentials that originated from the posterior temporal lobe statistically significantly changed during late face processing (600-700 ms) after stimulus, rather than in early face processing activities, such as P1 and N170 responses. Source localization revealed that the conditioned neutral faces increased activity in the right fusiform gyrus (FG). This study also developed an efficient method for detecting implicit negative emotional responses to specific faces by using EEG signals. A classification method based on a support vector machine enables the easy classification of neutral faces that trigger specific individual emotions. In accordance with this classification, a face on a computer morphs into a sad or displeased countenance. The proposed method could be incorporated as a part of non-verbal communication tools to enable emotional expression.

A Symbiotic Brain-Machine Interface through Value-Based Decision Making

PubMed Central

Mahmoudi, Babak; Sanchez, Justin C.

2011-01-01

Background In the development of Brain Machine Interfaces (BMIs), there is a great need to enable users to interact with changing environments during the activities of daily life. It is expected that the number and scope of the learning tasks encountered during interaction with the environment as well as the pattern of brain activity will vary over time. These conditions, in addition to neural reorganization, pose a challenge to decoding neural commands for BMIs. We have developed a new BMI framework in which a computational agent symbiotically decoded users' intended actions by utilizing both motor commands and goal information directly from the brain through a continuous Perception-Action-Reward Cycle (PARC). Methodology The control architecture designed was based on Actor-Critic learning, which is a PARC-based reinforcement learning method. Our neurophysiology studies in rat models suggested that Nucleus Accumbens (NAcc) contained a rich representation of goal information in terms of predicting the probability of earning reward and it could be translated into an evaluative feedback for adaptation of the decoder with high precision. Simulated neural control experiments showed that the system was able to maintain high performance in decoding neural motor commands during novel tasks or in the presence of reorganization in the neural input. We then implanted a dual micro-wire array in the primary motor cortex (M1) and the NAcc of rat brain and implemented a full closed-loop system in which robot actions were decoded from the single unit activity in M1 based on an evaluative feedback that was estimated from NAcc. Conclusions Our results suggest that adapting the BMI decoder with an evaluative feedback that is directly extracted from the brain is a possible solution to the problem of operating BMIs in changing environments with dynamic neural signals. During closed-loop control, the agent was able to solve a reaching task by capturing the action and reward interdependency in the brain. PMID:21423797

Inverted BMI rather than BMI is a better proxy for percentage of body fat.

PubMed

Nevill, Alan M; Stavropoulos-Kalinoglou, Antonios; Metsios, Giorgos S; Koutedakis, Yiannis; Holder, Roger L; Kitas, George D; Mohammed, Mohammed A

2011-11-01

Percentage of body fat (BF%) is a known risk factor for a range of healthcare problems but is difficult to measure. An easy to measure proxy is the weight/height(2) ratio known as the Body Mass Index (BMI kg/m(2)). However, BMI does have some inherent weaknesses which are readily overcome by its inverse iBMI (1000/BMI, cm(2)/kg). The association between BF% and both BMI and iBMI together with their distributional properties was explored using previously published data from healthy (n = 2993) and diseased populations (n = 298). BMI is skewed whereas iBMI is symmetrical and so is better approximated by the normal distribution. The relationship between BF% and BMI is curved, but that of iBMI and BF% is linear and thus iBMI explains more of the variation in BF% than BMI. For example a unit increase in BMI for a group of thin women represents an increase of 2.3% in BF, but for obese women this represents only a 0.3% increase in BF-a 7-fold difference. The curvature stems from body mass being the numerator in BMI but the denominator in BF% resulting in a form of hyperbolic curve which is not the case with iBMI. Furthermore, BMI and iBMI have different relationships (interaction) with BF% for men and women, but these differences are less marked with iBMI. Overall, these characteristics of iBMI favour its use over BMI, especially in statistical models.

Using BMI to Determine Cardiovascular Risk in Childhood: How Do the BMI Cutoffs Fare?

PubMed Central

Skinner, Asheley Cockrell; Mayer, Michelle L.; Flower, Kori; Perrin, Eliana M.; Weinberger, Morris

2010-01-01

OBJECTIVE Although adverse health outcomes are increased among children with BMI above the 85th (overweight) and 95th (obese) percentiles, previous studies have not clearly defined the BMI percentile at which adverse health outcomes begin to increase. We examined whether the existing BMI percentile cutoffs are optimal for defining increased risk for dyslipidemia, dysglycemia, and hypertension. METHODS This was a cross-sectional analysis of the National Health and Nutrition Examination Survey from 2001 to 2006. Studied were 8216 children aged 6 to 17 years, representative of the US population. BMI was calculated by using measured height and weight and converted to percentiles for age in months and gender. Outcome measures (dyslipidemia, dysglycemia, and hypertension) were based on laboratory and physical examination results; these were analyzed as both continuous and categorical outcomes. RESULTS Significant increases for total cholesterol values and prevalence of abnormal cholesterol begin at the 80th percentile. Significant increases in glycohemoglobin values and prevalence of abnormal values begin at the 99th percentile. Consistent significant increases in the prevalence of high or borderline systolic blood pressure begin at the 90th percentile. CONCLUSIONS Intervening for overweight children and their health requires clinical interventions that target the right children. On the basis of our data, a judicious approach to screening could include consideration of lipid screening for children beginning at the 80th percentile but for dysglycemia at the 99th percentile. Current definitions of overweight and obese may be more useful for general recognition of potential health problems and discussions with parents and children about the need to address childhood obesity. WHAT'S KNOWN ON THIS SUBJECT: Previous research has shown that cardiovascular risk factors are related to the currently used definitions of obesity in children but has not specified the BMI percentiles at which risk increases.WHAT THIS STUDY ADDS: Nationally representative data indicate greater risk for abnormal lipid values in children who are not considered overweight by current definitions, risk for diabetes only in very obese children, and risk for hypertension at the 90th percentile of BMI. PMID:19858150

Contribution of 32 GWAS-Identified Common Variants to Severe Obesity in European Adults Referred for Bariatric Surgery

PubMed Central

Yousseif, Ahmed; Pucci, Andrea; Santini, Ferruccio; Karra, Efthimia; Querci, Giorgia; Pelosini, Caterina; McCarthy, Mark I.; Lindgren, Cecilia M.; Batterham, Rachel L.

2013-01-01

The prevalence of severe obesity, defined as body mass index (BMI) ≥35.0 kg/m2, is rising rapidly. Given the disproportionately high health burden and healthcare costs associated with this condition, understanding the underlying aetiology, including predisposing genetic factors, is a biomedical research priority. Previous studies have suggested that severe obesity represents an extreme tail of the population BMI variation, reflecting shared genetic factors operating across the spectrum. Here, we sought to determine whether a panel of 32 known common obesity-susceptibility variants contribute to severe obesity in patients (n = 1,003, mean BMI 48.4±8.1 kg/m2) attending bariatric surgery clinics in two European centres. We examined the effects of these 32 common variants on obesity risk and BMI, both as individual markers and in combination as a genetic risk score, in a comparison with normal-weight controls (n = 1,809, BMI 18.0–24.9 kg/m2); an approach which, to our knowledge, has not been previously undertaken in the setting of a bariatric clinic. We found strong associations with severe obesity for SNP rs9939609 within the FTO gene (P = 9.3×10−8) and SNP rs2815752 near the NEGR1 gene (P = 3.6×10−4), and directionally consistent nominal associations (P<0.05) for 12 other SNPs. The genetic risk score associated with severe obesity (P = 8.3×10−11) but, within the bariatric cohort, this score did not associate with BMI itself (P = 0.264). Our results show significant effects of individual BMI-associated common variants within a relatively small sample size of bariatric patients. Furthermore, the burden of such low-penetrant risk alleles contributes to severe obesity in this population. Our findings support that severe obesity observed in bariatric patients represents an extreme tail of the population BMI variation. Moreover, future genetic studies focused on bariatric patients may provide valuable insights into the pathogenesis of obesity at a population level. PMID:23950990

What effect do attempts to lose weight have on the observed relationship between nutrition behaviors and body mass index among adolescents?

PubMed

Utter, Jennifer; Scragg, Robert; Ni Mhurchu, Cliona; Schaaf, David

2007-09-19

Little research has given consideration to how people's weight control behaviors may moderate the relationships between nutrition and body mass index (BMI) in large cross-sectional studies. The objective of the current study is to determine how attempts to lose weight confound the relationships between nutrition behaviors and BMI among a population of predominately overweight adolescents. Data were drawn from the baseline measurements of the Pacific OPIC (Obesity Prevention In Communities). Participants included approximately 3500 high school students in New Zealand. Students in the sample primarily identified as a Pacific Island ethnicity (57%) and the mean age for participants was 14.8 years. Participants completed a questionnaire about nutrition and physical activity patterns and were weighed and measured for height. In our sample, 57% of students were overweight/obese, with the highest prevalence among Pacific Island students (71%). Approximately 50% of students were currently trying to lose weight, and this was more common among females, Pacific Island students and overweight/obese students. Examination of the nutritional correlates of BMI in the total population found inverse relationships between BMI and consumption of high-fat/high-sugar foods and positive relationships between BMI and eating 5 or more fruits and vegetables a day (all significant after controlling for age, sex, and ethnicity). For example, students who drank the most soft drinks or ate fruit and vegetables infrequently had the lowest mean BMI. Students' attempts to change their weight significantly moderated the relationships between most nutritional behaviors and BMI. In most cases, among students not trying to change their weight, expected relationships were observed; among students trying to lose weight, unexpected or no relationships were observed. Our findings suggest that among this population of predominately overweight students, solely relying on cross-sectional findings between nutrition behaviours and BMI would misinform intervention strategies. It appears that many students are already taking appropriate steps to reduce their weight. Intervention efforts should now move beyond education-based strategies to environmental changes that support students in adopting healthier nutrition practices.

Characterizing severe and enduring anorexia nervosa: An empirical approach.

PubMed

Wildes, Jennifer E; Forbush, Kelsie T; Hagan, Kelsey E; Marcus, Marsha D; Attia, Evelyn; Gianini, Loren M; Wu, Wei

2017-04-01

Targeted approaches for the treatment of severe and enduring anorexia nervosa (SE-AN) have been recommended, but there is no consensus definition of SE-AN to inform research and clinical practice. This study aimed to take initial steps toward developing an empirically based definition of SE-AN by characterizing associations among putative indicators of severity and chronicity in eating disorders. Patients with AN (N = 355) completed interviews and questionnaires at treatment admission and discharge; height and weight were assessed to calculate body mass index (BMI). Structural equation mixture modeling was used to test whether associations among potential indicators of SE-AN (illness duration, treatment history, BMI, binge eating, purging, quality-of-life) formed distinct subgroups, a single group with one or more dimensions, or a combination of subgroups and dimensions. A three-factor (dimensional), two-profile (categorical) mixture model provided the best fit to the data. Factor 1 included eating disorder behaviors; Factor 2 comprised quality-of-life domains; Factor 3 was characterized by illness duration, number of hospitalizations, and admission BMI. Profiles differed on eating disorder behaviors and quality-of-life, but not on indicators of chronicity or BMI. Factor scores, but not profile membership, predicted outcome at discharge from treatment. Data suggest that patients with AN can be classified on the basis of eating disorder behaviors and quality-of-life, but there was no evidence for a chronic subgroup of AN. Rather, indices of chronicity varied dimensionally within each class. Given that current definitions of SE-AN rely on illness duration, these findings have implications for research and clinical practice. © 2016 Wiley Periodicals, Inc.

Consumption of a high glycemic load but not a high glycemic index diet is marginally associated with oxidative stress in young women.

PubMed

Arikawa, Andrea Y; Jakits, Holly E; Flood, Andrew; Thomas, William; Gross, Myron; Schmitz, Kathryn H; Kurzer, Mindy S

2015-01-01

Research studies have suggested that chronic consumption of high glycemic index foods may lead to chronically high oxidative stress. This is important because oxidative stress is suspected to be an early event in the etiology of many disease processes. We hypothesized that dietary glycemic index and glycemic load were positively associated with oxidative stress assessed by plasma F2-isoprostanes in healthy, premenopausal women (body mass index [BMI] = 24.7 ± 4.8 kg/m(2) and age 25.3 ± 3.5 years, mean ± SD). We measured plasma F2-isoprostanes in 306 healthy premenopausal women at the baseline visit for the Women In Steady Exercise Research study, using gas chromatography-mass spectrometry. Dietary glycemic index and load were calculated from the National Cancer Institute Diet History Questionnaire, and participants were divided into quartiles of dietary glycemic index and of glycemic load. Plasma F2-isoprostanes were compared across quartile groups of dietary glycemic index and glycemic load using linear regression models. Plasma F2-isoprostanes (pg/mL) increased with quartile of glycemic load (test for linear trend, P = .033), and also increased with quartile of glycemic index in participants with BMI ≥ 25 (P = .035) but not in those with BMI <25 (P = .924). After adjustment for BMI, alcohol consumption and total energy intake, both these positive trends remained marginally significant (P = .123 for quartiles of glycemic index and P = .065 for quartiles of glycemic load). Copyright © 2015 Elsevier Inc. All rights reserved.

Revised infant dietary recommendations: the impact of maternal education and other parental factors on adherence rates in Iceland.

PubMed

Thorisdottir, Asa Vala; Gunnarsdottir, Ingibjorg; Thorsdottir, Inga

2013-02-01

Revised infant dietary recommendations from the Icelandic Nutrition Council (Nutrition: the first twelve months. Reykjavík, Iceland: The Icelandic Nutrition Council, 2003) are outlined in a booklet provided during free postnatal care. These focus on increasing the duration of exclusive and total breastfeeding and reducing cow's milk consumption. This study explored whether maternal education and other parental factors affected whether mothers followed the recommendations. Mothers of randomly selected healthy infants (n = 200) completed questionnaires on body mass index (BMI), age, education (basic, medium and higher), household income, smoking and parental factors. Dietary data were collected during home visits by a researcher (0-4 months) and through monthly food records completed by parents or caregivers (5-12 months). Each maternal education level increased breastfeeding duration by 0.72 months (95% CI = 0.04, 1.39) and reduced cow's milk consumption by 36.7 mL/day (95% CI = -70.11, -3.03), when adjusted for maternal BMI, age, smoking and family income. Maternal education was not associated with duration of exclusive breastfeeding. Duration of exclusive and total breastfeeding was inversely associated with maternal BMI, B = -0.10 (95% CI = -0.16, -0.05) and -0.13 (95% CI = -0.23, -0.03), respectively. Mothers with higher education appear to have adapted more easily to the revised recommendations on infant diet, particularly when their infants are 6-12 months old. Higher maternal BMI was associated with shorter duration of both exclusive and total breastfeeding. ©2012 Unit for Nutrition Research/Acta Paediatrica ©2012 Foundation Acta Paediatrica.

The association between worksite physical environment and employee nutrition, and physical activity behavior and weight status

PubMed Central

Almeida, Fabio A.; Wall, Sarah S.; You, Wen; Harden, Samantha M.; Hill, Jennie L.; Krippendorf, Blake E.; Estabrooks, Paul A.

2014-01-01

Objective Explore the relationship between worksite physical environment and employee dietary intake, physical activity behavior, and weight status. Methods Two trained research assistants completed audits (Checklist of Health Promotion Environments at Worksites) at each worksite (n = 28). Employees (n = 6,261) completed a brief health survey prior to participation in a weight loss program. Results Employees’ access to outdoor areas was directly associated with lower BMI, while access to workout facilities within a worksite was associated with higher BMI. The presence of a cafeteria and fewer vending machines were directly associated with better eating habits. Better eating habits and meeting physical activity recommendations were both related to lower BMI. Conclusions Selected environmental factors in worksites were significantly associated with employee behaviors and weight status; providing additional intervention targets to change the worksite environment and promote employee weight loss. PMID:24988105

A Review of the Literature on Policies Directed at the Youth Consumption of Sugar Sweetened Beverages123

PubMed Central

Levy, David T.; Friend, Karen B.; Wang, Y. Claire

2011-01-01

Sugar sweetened beverages (SSB) constitute a large percentage of energy consumed by youth. This paper reviews the literature on school nutrition policies and price interventions directed at youth SSB consumption. In addition to considering the direct effect of policies on SSB consumption, we provide an overview of the literature on how SSB consumption affects total energy intake (TEI) and BMI, as well as on how TEI affects BMI. By considering each of these links, we attempted to gauge the effect of policies directed at SSB consumption, as well as highlight areas that merit future research. We found that school nutrition and price policies reduce SSB consumption and that reduced SSB consumption is associated with a reduction in energy intake that can influence BMI. Policies directed at SSB consumption can play an important role in reducing youth overweight and obesity. PMID:22332051

Is decision-making ability related to food choice and facets of eating behaviour in adolescents?

PubMed

Macchi, Rosemarie; MacKew, Laura; Davis, Caroline

2017-09-01

To test the prediction that poor decision-making would predict poor eating-related behaviours, which in turn would relate to elevated body mass index (BMI) percentile. Associations among decision-making ability, eating behaviours, and BMI percentile were examined in a sample of 311 healthy male and female adolescents, aged 14-18 years. Structural equation modelling was used to test the proposed relationships. The predicted model was a good fit to the data and all paths between latent and indicator variables were significant. Impulsive responding significantly predicted poor food choice and overeating. No significant relationships emerged between eating-related variables and BMI percentile. Findings from this study extend the existing research in adults and offer a more comprehensive understanding of factors that may contribute to eating behaviours and weight status in teenagers. Copyright © 2017 Elsevier Ltd. All rights reserved.

The association between worksite physical environment and employee nutrition, and physical activity behavior and weight status.

PubMed

Almeida, Fabio A; Wall, Sarah S; You, Wen; Harden, Samantha M; Hill, Jennie L; Krippendorf, Blake E; Estabrooks, Paul A

2014-07-01

To explore the relationship between worksite physical environment and employee dietary intake, physical activity behavior, and weight status. Two trained research assistants completed audits (Checklist of Health Promotion Environments at Worksites) at each worksite (n = 28). Employees (n = 6261) completed a brief health survey before participation in a weight loss program. Employees' access to outdoor areas was directly associated with lower body mass index (BMI), whereas access to workout facilities within a worksite was associated with higher BMI. The presence of a cafeteria and fewer vending machines was directly associated with better eating habits. Better eating habits and meeting physical activity recommendations were both related to lower BMI. Selected environmental factors in worksites were significantly associated with employee behaviors and weight status, providing additional intervention targets to change the worksite environment and promote employee weight loss.

The built environment moderates effects of family-based childhood obesity treatment over 2 years.

PubMed

Epstein, Leonard H; Raja, Samina; Daniel, Tinuke Oluyomi; Paluch, Rocco A; Wilfley, Denise E; Saelens, Brian E; Roemmich, James N

2012-10-01

Research suggests the neighborhood built environment is related to child physical activity and eating. The purpose of this study was to determine if characteristics of the neighborhood environment moderate the relationship between obesity treatment and weight loss, and if outcomes of particular treatments are moderated by built environment characteristics. The relationship between the built environment and standardized BMI (zBMI) changes for 191 8-12-year-old children who participated in one of four randomized, controlled trials of pediatric weight management was assessed using mixed models analysis of covariance. At 2-year follow-up, greater parkland, fewer convenience stores, and fewer supermarkets were associated with greater zBMI reduction across all interventions. No treatments interacted with characteristics of the built environment. Activity- and eating-related built neighborhood characteristics are associated with child success in behavioral obesity treatments. Efficacy may be improved by individualizing treatments based on built environment characteristics.

Peer effects in adolescent BMI: evidence from Spain.

PubMed

Mora, Toni; Gil, Joan

2013-05-01

This paper extends the recent literature on the influence of peers on adolescent weight on three new fronts. First, based on a survey of secondary school students in Spain in which peers are formed by nominated classmate friends, we find a more powerful positive and significant causal effect of friends' mean BMI on adolescent BMI than previous US-based research. These results are in line with international data, which show that peer group contact tends to vary across countries. Our findings cover a large set of controls, fixed effects, the testing of correlated unobservables, contextual influences and instrumental variables. Second, social interactions are identified through the property of intransitivity in network relationships. Finally, we report evidence of a strong, positive effect of peer pressure on several subgroups of adolescents in an attempt to study their vulnerability to social influences. Copyright © 2012 John Wiley & Sons, Ltd.

A research on relationship between ABO blood groups and body mass index among Turkish seafarers.

PubMed

Nas, Selçuk; Fışkın, Remzi

2017-01-01

The present study aims to investigate and to reveal the relationship between ABO blood groups and body mass index (BMI) and obesity among Turkish seafarers by using the health examination reports data obtained from 2009 to 2016. The data on age, gender, weight, height and blood groups obtained from 298,247 medical examination reports of Turkish seafarers were used with the official permission of Directorate General of Health for Border and Coastal Areas. Only 116,871 reports included blood group data. Regression and analysis of variance (ANOVA) tests were performed to survey relationship between variables. The results of the study were compared with other studies in the related literature. It has been revealed that AB Rh (-) group was associated the highest mean BMI value (mean: 25.952). It is suggested that seafarers with AB Rh (-) blood group, who have the highest mean BMI value, should pay special attention to their weight.

Socioeconomic inequalities and body mass index in Västerbotten County, Sweden: a longitudinal study of life course influences over two decades.

PubMed

Padyab, Mojgan; Norberg, Margareta

2014-05-07

Life course socioeconomic inequalities in heart disease, stroke and all-cause mortality are well studied in Sweden. However, few studies have sought to explain the mechanism for such associations mainly due to lack of longitudinal data with multiple measures of socioeconomic status (SES) across the life course. Given the population health concern about how socioeconomic inequality is related to poorer health, we aim to tackle obesity as one of the prime suspects that could explain the association between SES inequality and cardiovascular disease and consequently premature death. The aim of this study is to test which life course model best describes the association between socioeconomic disadvantage and obesity among 60 year old inhabitants of Västerbotten County in Northern Sweden. A birth cohort consisting of 3340 individuals born between 1930 and 1932 was studied. Body mass index (BMI) at the age of 60 and information on socioeconomic status at three stages of life (ages 40, 50, and 60 years) was collected. Independent samples t-test was used to compare BMI between advantaged and disadvantaged groups and one-way ANOVA was used to compare BMI among eight SES trajectories. We applied a structured modeling approach to examine three different hypothesized life course SES models (accumulation, critical period, and social mobility) in relation to BMI. We found sex differences in the way that late adulthood socioeconomic disadvantage is associated with BMI among inhabitants of Northern Sweden. Our study suggests that social adversity in all stages of late adulthood is a particularly important indicator for addressing the social gradients in BMI among women in Northern Sweden and that unhealthy behaviors in terms of smoking and physical inactivity are insufficient to explain the relationships between social and lifestyle inequalities and BMI. In order for local authorities to develop informed preventive efforts, we suggest further research to identify modifiable risk factors across the life course which could explain this health inequality.

What Bed Size Does a Patient Need? The Relationship Between Body Mass Index and Space Required to Turn in Bed.

PubMed

Wiggermann, Neal; Smith, Kathryn; Kumpar, Dee

A bed that is too small to allow patients to turn from supine to side lying increases the difficulty of mobilizing patients, which can increase risk of musculoskeletal injury to caregivers, increase risk of pressure injuries to patients, and reduce patient comfort. Currently, no guidance is available for what patient sizes are accommodated by the standard 91cm (36 in.)-wide hospital bed, and no studies have evaluated the relationship between anthropometric attributes and space required to turn in bed. The purpose of this research was to determine how much space individuals occupy when turning from supine to side lying as predicted by their anthropometry (i.e., body dimensions) to establish guidance on selecting the appropriate bed size. Forty-seven adult participants (24 female) with body mass index (BMI) from 20 to 76 kg/m participated in a laboratory study. Body dimensions were measured, and the envelope of space required to turn was determined using motion capture. Linear regressions estimated the relationship between anthropometric attributes and space occupied when turning. BMI was strongly correlated (R = .88) with the space required to turn. Based on the linear regressions, individuals with BMI up to 35 kg/m could turn left and right within 91 cm and individuals with BMI up to 45 kg/m could turn one direction within 91 cm. BMI is a good predictor of the space required to turn from supine to lateral. Nurses should consider placing patients that are unable to laterally reposition themselves on a wider bed when BMI is greater than 35 kg/m and should consider placing all patients greater than 45 kg/m on a wider bed regardless of mobility. Hospital administrators can use historical demographic information about the BMI of their patient populations to plan facility-level equipment procurement for equipment that accommodates their patients.

Higher Body Mass Index Is Associated With Greater Proportions of Effector CD8+ T Cells Expressing CD57 in Women Living With HIV.

PubMed

Reid, Michael J A; Baxi, Sanjiv M; Sheira, Lila A; Landay, Alan L; Frongillo, Edward A; Adedimeji, Adebola; Cohen, Mardge H; Wentz, Eryka; Gustafson, Deborah R; Merenstein, Daniel; Hunt, Peter W; Tien, Phyllis C; Weiser, Sheri D

2017-08-15

A low proportion of CD28CD8 T cells that express CD57 is associated with increased mortality in HIV infection. The effect of increasing body mass index (BMI) changes in the proportion of CD57CD28CD8 T cells among HIV-infected individuals on antiretroviral therapy is unknown. In a US cohort of HIV-infected women, we evaluated associations of BMI and waist circumference with 3 distinct CD8 T cell phenotypes: % CD28CD57CD8 T cells, % CD57 of CD28CD8 T cells, and % CD28 of all CD8 T cells. Multivariable linear regression analysis was used to estimate beta coefficients for each of 3 T-cell phenotypes. Covariates included HIV parameters (current and nadir CD4, current viral load), demographics (age, race, income, and study site), and lifestyle (tobacco and alcohol use) factors. Of 225 participants, the median age was 46 years and 50% were obese (BMI >30 m/kg). Greater BMI and waist circumference were both associated with higher % CD28CD57CD8 T cells and % CD57 of all CD28CD8 T cells in multivariable analysis, including adjustment for HIV viral load (all P < 0.05). The association between greater BMI and the overall proportion of CD28 CD8 cells in fully adjusted models (0.078, 95% confidence interval: -0.053 to 0.209) was not significant. In this analysis, greater BMI and waist circumference are associated with greater expression of CD57 on CD28CD8 T cells and a greater proportion of CD57CD28 CD8 T cells. These findings may indicate that increasing BMI is immunologically protective in HIV-infected women. Future research is needed to understand the prognostic importance of these associations on clinical outcomes.

Children's eating behavior, feeding practices of parents and weight problems in early childhood: results from the population-based Generation R Study

PubMed Central

2012-01-01

Background Weight problems that arise in the first years of life tend to persist. Behavioral research in this period can provide information on the modifiable etiology of unhealthy weight. The present study aimed to replicate findings from previous small-scale studies by examining whether different aspects of preschooler’s eating behavior and parental feeding practices are associated with body mass index (BMI) and weight status -including underweight, overweight and obesity- in a population sample of preschool children. Methods Cross-sectional data on the Child Eating Behaviour Questionnaire, Child Feeding Questionnaire and objectively measured BMI was available for 4987 four-year-olds participating in a population-based cohort in the Netherlands. Results Thirteen percent of the preschoolers had underweight, 8% overweight, and 2% obesity. Higher levels of children’s Food Responsiveness, Enjoyment of Food and parental Restriction were associated with a higher mean BMI independent of measured confounders. Emotional Undereating, Satiety Responsiveness and Fussiness of children as well as parents’ Pressure to Eat were negatively related with children’s BMI. Similar trends were found with BMI categorized into underweight, normal weight, overweight and obesity. Part of the association between children’s eating behaviors and BMI was accounted for by parental feeding practices (changes in effect estimates: 20-43%), while children’s eating behaviors in turn explained part of the relation between parental feeding and child BMI (changes in effect estimates: 33-47%). Conclusions This study provides important information by showing how young children’s eating behaviors and parental feeding patterns differ between children with normal weight, underweight and overweight. The high prevalence of under- and overweight among preschoolers suggest prevention interventions targeting unhealthy weights should start early in life. Although longitudinal studies are necessary to ascertain causal directions, efforts to prevent or treat unhealthy child weight might benefit from a focus on changing the behaviors of both children and their parents. PMID:23110748

Evaluation of a prognostic scoring system based on the systemic inflammatory and nutritional status of patients with locally advanced non-small-cell lung cancer treated with chemoradiotherapy.

PubMed

Mitsuyoshi, Takamasa; Matsuo, Yukinori; Itou, Hitoshi; Shintani, Takashi; Iizuka, Yusuke; Kim, Young Hak; Mizowaki, Takashi

2018-01-01

Systemic inflammation and poor nutritional status have a negative effect on the outcomes of cancer. Here, we analyzed the effects of the pretreatment inflammatory and nutritional status on clinical outcomes of locally advanced non-small-cell lung cancer (NSCLC) patients treated with chemoradiotherapy. We retrospectively reviewed 89 patients with locally advanced NSCLC treated with chemoradiotherapy between July 2006 and June 2013. Serum C-reactive protein (CRP) was assessed as an inflammatory marker, and serum albumin, body mass index (BMI) and skeletal mass index were assessed as nutritional status markers. The relationships between these markers and overall survival (OS) were assessed. The median OS was 24.6 months [95% confidence interval (CI): 19.4-39.3 months]. During follow-up, 58 patients (65%) had disease recurrence and 52 patients (58%) died. In multivariate Cox hazard analysis, CRP levels and BMI approached but did not achieve a significant association with OS (P = 0.062 and 0.094, respectively). Recursive partitioning analysis identified three prognostic groups based on hazard similarity (CRP-BMI scores): 0 = CRP < 0.3 mg/dl, 1 = CRP ≥ 0.3 mg/dl and BMI ≥ 18.5 kg/m2, and 2 = CRP ≥ 0.3 mg/dl and BMI < 18.5 kg/m2. The CRP-BMI score was significantly associated with OS (P = 0.023). Patients with scores of 0, 1 and 2 had median OS of 39.3, 24.5 and 14.5 months, respectively, and the scores also predicted the probability of receiving salvage treatment after recurrence. The CRP-BMI score is thus a simple and useful prognostic marker of clinical outcome for patients with locally advanced NSCLC treated with chemoradiotherapy. © The Author 2017. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

Similarity in percent body fat between white and Vietnamese women: implication for a universal definition of obesity.

PubMed

Ho-Pham, Lan T; Lai, Thai Q; Nguyen, Nguyen D; Barrett-Connor, Elizabeth; Nguyen, Tuan V

2010-06-01

It has been widely assumed that for a given BMI, Asians have higher percent body fat (PBF) than whites, and that the BMI threshold for defining obesity in Asians should be lower than the threshold for whites. This study sought to test this assumption by comparing the PBF between US white and Vietnamese women. The study was designed as a comparative cross-sectional investigation. In the first study, 210 Vietnamese women ages between 50 and 85 were randomly selected from various districts in Ho Chi Minh City (Vietnam). In the second study, 419 women of the same age range were randomly selected from the Rancho Bernardo Study (San Diego, CA). In both studies, lean mass (LM) and fat mass (FM) were measured by dual-energy X-ray absorptiometry (DXA) (QDR 4500; Hologic). PBF was derived as FM over body weight. Compared with Vietnamese women, white women had much more FM (24.8 +/- 8.1 kg vs. 18.8 +/- 4.9 kg; P < 0.0001) and greater PBF (36.4 +/- 6.5% vs. 35.0 +/- 6.2%; P = 0.012). However, there was no significant difference in PBF between the two groups after matching for BMI (35.1 +/- 6.2% vs. 35.0 +/- 5.7%; P = 0.87) or for age and BMI (35.6 +/- 5.1% vs. 35.8 +/- 5.9%; P = 0.79). Using the criteria of BMI >or=30, 19% of US white women and 5% of Vietnamese women were classified as obese. Approximately 54% of US white women and 53% of Vietnamese women had their PBF >35% (P = 0.80). Although white women had greater BMI, body weight, and FM than Vietnamese women, their PBF was virtually identical. Further research is required to derive a more appropriate BMI threshold for defining obesity for Asian women.

What Bed Size Does a Patient Need? The Relationship Between Body Mass Index and Space Required to Turn in Bed

PubMed Central

Wiggermann, Neal; Smith, Kathryn; Kumpar, Dee

2017-01-01

Background A bed that is too small to allow patients to turn from supine to side lying increases the difficulty of mobilizing patients, which can increase risk of musculoskeletal injury to caregivers, increase risk of pressure injuries to patients, and reduce patient comfort. Currently, no guidance is available for what patient sizes are accommodated by the standard 91cm (36 in.)-wide hospital bed, and no studies have evaluated the relationship between anthropometric attributes and space required to turn in bed. Objective The purpose of this research was to determine how much space individuals occupy when turning from supine to side lying as predicted by their anthropometry (i.e., body dimensions) to establish guidance on selecting the appropriate bed size. Methods Forty-seven adult participants (24 female) with body mass index (BMI) from 20 to 76 kg/m2 participated in a laboratory study. Body dimensions were measured, and the envelope of space required to turn was determined using motion capture. Linear regressions estimated the relationship between anthropometric attributes and space occupied when turning. Results BMI was strongly correlated (R2 = .88) with the space required to turn. Based on the linear regressions, individuals with BMI up to 35 kg/m2 could turn left and right within 91 cm and individuals with BMI up to 45 kg/m2 could turn one direction within 91 cm. Discussion BMI is a good predictor of the space required to turn from supine to lateral. Nurses should consider placing patients that are unable to laterally reposition themselves on a wider bed when BMI is greater than 35 kg/m2 and should consider placing all patients greater than 45 kg/m2 on a wider bed regardless of mobility. Hospital administrators can use historical demographic information about the BMI of their patient populations to plan facility-level equipment procurement for equipment that accommodates their patients. PMID:28968285

Effect of Obesity and Underweight Status on Perioperative Outcomes of Congenital Heart Operations in Children, Adolescents, and Young Adults: An Analysis of Data From the Society of Thoracic Surgeons Database.

PubMed

O'Byrne, Michael L; Kim, Sunghee; Hornik, Christoph P; Yerokun, Babatunde A; Matsouaka, Roland A; Jacobs, Jeffrey P; Jacobs, Marshall L; Jonas, Richard A

2017-08-22

Extreme body mass index (BMI; either very high or very low) has been associated with increased risk of adverse perioperative outcome in adults undergoing cardiac surgery. The effect of BMI on perioperative outcomes in congenital heart disease patients has not been evaluated. A multicenter retrospective cohort study was performed studying patients 10 to 35 years of age undergoing a congenital heart disease operation in the Society of Thoracic Surgeons Congenital Heart Surgery Database between January 1, 2010, and December 31, 2015. The primary outcomes were operative mortality and a composite outcome (1 or more of operative mortality, major adverse event, prolonged hospital length of stay, and wound infection/dehiscence). The associations between age- and sex-adjusted BMI percentiles and these outcomes were assessed, with adjustment for patient-level risk factors, with multivariate logistic regression. Of 18 337 patients (118 centers), 16% were obese, 15% were overweight, 53% were normal weight, 7% were underweight, and 9% were severely underweight. Observed risks of operative mortality ( P =0.04) and composite outcome ( P <0.0001) were higher in severely underweight and obese subjects. Severely underweight BMI was associated with increased unplanned cardiac operation and reoperation for bleeding. Obesity was associated with increased risk of wound infection. In multivariable analysis, the association between BMI and operative mortality was no longer significant. Obese (odds ratio, 1.28; P =0.008), severely underweight (odds ratio, 1.29; P <0.0001), and underweight (odds ratio, 1.39; P =0.002) subjects were associated with increased risk of composite outcome. Obesity and underweight BMI were associated with increased risk of composite adverse outcome independently of other risk factors. Further research is necessary to determine whether BMI represents a modifiable risk factor for perioperative outcome. © 2017 American Heart Association, Inc.