The TP53 gene polymorphisms and survival of sporadic breast cancer patients.

PubMed

Bišof, V; Salihović, M Peričić; Narančić, N Smolej; Skarić-Jurić, T; Jakić-Razumović, J; Janićijević, B; Rudan, P

2012-06-01

The TP53 gene polymorphisms, Arg72Pro and PIN3 (+16 bp), can have prognostic and predictive value in different cancers including breast cancer. The aim of the present study is to investigate a potential association between different genotypes of these polymorphisms and clinicopathological variables with survival of breast cancer patients in Croatian population. Ninety-four women with sporadic breast cancer were retrospectively analyzed. Median follow-up period was 67.9 months. The effects of basic clinical and histopathological characteristics of tumor on survival were tested by Cox's proportional hazards regression analysis. The TNM stage was associated with overall survival by Kaplan-Meier analysis, univariate, and multivariate Cox's proportional hazards regression analysis, while grade was associated with survival by Kaplan-Meier analysis and univariate Cox's proportional hazards regression analysis. Different genotypes of the Arg72Pro and PIN3 (+16 bp) polymorphisms had no significant impact on survival in breast cancer patients. However, in subgroup of patients treated with chemotherapy without anthracycline, the A2A2 genotype of the PIN3 (+16 bp) polymorphism was associated with poorer overall survival than other genotypes by Kaplan-Meier analysis (P = 0.048). The TP53 polymorphisms, Arg72Pro and PIN3 (+16 bp), had no impact on survival in unselected sporadic breast cancer patients in Croatian population. However, the results support the role of the A2A2 genotype of the PIN3 (+16 bp) polymorphism as a marker for identification of patients that may benefit from anthracycline-containing chemotherapy.

Hazard Function Estimation with Cause-of-Death Data Missing at Random.

PubMed

Wang, Qihua; Dinse, Gregg E; Liu, Chunling

2012-04-01

Hazard function estimation is an important part of survival analysis. Interest often centers on estimating the hazard function associated with a particular cause of death. We propose three nonparametric kernel estimators for the hazard function, all of which are appropriate when death times are subject to random censorship and censoring indicators can be missing at random. Specifically, we present a regression surrogate estimator, an imputation estimator, and an inverse probability weighted estimator. All three estimators are uniformly strongly consistent and asymptotically normal. We derive asymptotic representations of the mean squared error and the mean integrated squared error for these estimators and we discuss a data-driven bandwidth selection method. A simulation study, conducted to assess finite sample behavior, demonstrates that the proposed hazard estimators perform relatively well. We illustrate our methods with an analysis of some vascular disease data.

PSHREG: A SAS macro for proportional and nonproportional subdistribution hazards regression

PubMed Central

Kohl, Maria; Plischke, Max; Leffondré, Karen; Heinze, Georg

2015-01-01

We present a new SAS macro %pshreg that can be used to fit a proportional subdistribution hazards model for survival data subject to competing risks. Our macro first modifies the input data set appropriately and then applies SAS's standard Cox regression procedure, PROC PHREG, using weights and counting-process style of specifying survival times to the modified data set. The modified data set can also be used to estimate cumulative incidence curves for the event of interest. The application of PROC PHREG has several advantages, e.g., it directly enables the user to apply the Firth correction, which has been proposed as a solution to the problem of undefined (infinite) maximum likelihood estimates in Cox regression, frequently encountered in small sample analyses. Deviation from proportional subdistribution hazards can be detected by both inspecting Schoenfeld-type residuals and testing correlation of these residuals with time, or by including interactions of covariates with functions of time. We illustrate application of these extended methods for competing risk regression using our macro, which is freely available at: http://cemsiis.meduniwien.ac.at/en/kb/science-research/software/statistical-software/pshreg, by means of analysis of a real chronic kidney disease study. We discuss differences in features and capabilities of %pshreg and the recent (January 2014) SAS PROC PHREG implementation of proportional subdistribution hazards modelling. PMID:25572709

Covariate Measurement Error Correction Methods in Mediation Analysis with Failure Time Data

PubMed Central

Zhao, Shanshan

2014-01-01

Summary Mediation analysis is important for understanding the mechanisms whereby one variable causes changes in another. Measurement error could obscure the ability of the potential mediator to explain such changes. This paper focuses on developing correction methods for measurement error in the mediator with failure time outcomes. We consider a broad definition of measurement error, including technical error and error associated with temporal variation. The underlying model with the ‘true’ mediator is assumed to be of the Cox proportional hazards model form. The induced hazard ratio for the observed mediator no longer has a simple form independent of the baseline hazard function, due to the conditioning event. We propose a mean-variance regression calibration approach and a follow-up time regression calibration approach, to approximate the partial likelihood for the induced hazard function. Both methods demonstrate value in assessing mediation effects in simulation studies. These methods are generalized to multiple biomarkers and to both case-cohort and nested case-control sampling design. We apply these correction methods to the Women's Health Initiative hormone therapy trials to understand the mediation effect of several serum sex hormone measures on the relationship between postmenopausal hormone therapy and breast cancer risk. PMID:25139469

Covariate measurement error correction methods in mediation analysis with failure time data.

PubMed

Zhao, Shanshan; Prentice, Ross L

2014-12-01

Mediation analysis is important for understanding the mechanisms whereby one variable causes changes in another. Measurement error could obscure the ability of the potential mediator to explain such changes. This article focuses on developing correction methods for measurement error in the mediator with failure time outcomes. We consider a broad definition of measurement error, including technical error, and error associated with temporal variation. The underlying model with the "true" mediator is assumed to be of the Cox proportional hazards model form. The induced hazard ratio for the observed mediator no longer has a simple form independent of the baseline hazard function, due to the conditioning event. We propose a mean-variance regression calibration approach and a follow-up time regression calibration approach, to approximate the partial likelihood for the induced hazard function. Both methods demonstrate value in assessing mediation effects in simulation studies. These methods are generalized to multiple biomarkers and to both case-cohort and nested case-control sampling designs. We apply these correction methods to the Women's Health Initiative hormone therapy trials to understand the mediation effect of several serum sex hormone measures on the relationship between postmenopausal hormone therapy and breast cancer risk. © 2014, The International Biometric Society.

Using multiple logistic regression and GIS technology to predict landslide hazard in northeast Kansas, USA

USGS Publications Warehouse

Ohlmacher, G.C.; Davis, J.C.

2003-01-01

Landslides in the hilly terrain along the Kansas and Missouri rivers in northeastern Kansas have caused millions of dollars in property damage during the last decade. To address this problem, a statistical method called multiple logistic regression has been used to create a landslide-hazard map for Atchison, Kansas, and surrounding areas. Data included digitized geology, slopes, and landslides, manipulated using ArcView GIS. Logistic regression relates predictor variables to the occurrence or nonoccurrence of landslides within geographic cells and uses the relationship to produce a map showing the probability of future landslides, given local slopes and geologic units. Results indicated that slope is the most important variable for estimating landslide hazard in the study area. Geologic units consisting mostly of shale, siltstone, and sandstone were most susceptible to landslides. Soil type and aspect ratio were considered but excluded from the final analysis because these variables did not significantly add to the predictive power of the logistic regression. Soil types were highly correlated with the geologic units, and no significant relationships existed between landslides and slope aspect. ?? 2003 Elsevier Science B.V. All rights reserved.

Hazard Regression Models of Early Mortality in Trauma Centers

PubMed Central

Clark, David E; Qian, Jing; Winchell, Robert J; Betensky, Rebecca A

2013-01-01

Background Factors affecting early hospital deaths after trauma may be different from factors affecting later hospital deaths, and the distribution of short and long prehospital times may vary among hospitals. Hazard regression (HR) models may therefore be more useful than logistic regression (LR) models for analysis of trauma mortality, especially when treatment effects at different time points are of interest. Study Design We obtained data for trauma center patients from the 2008–9 National Trauma Data Bank (NTDB). Cases were included if they had complete data for prehospital times, hospital times, survival outcome, age, vital signs, and severity scores. Cases were excluded if pulseless on admission, transferred in or out, or ISS<9. Using covariates proposed for the Trauma Quality Improvement Program and an indicator for each hospital, we compared LR models predicting survival at 8 hours after injury to HR models with survival censored at 8 hours. HR models were then modified to allow time-varying hospital effects. Results 85,327 patients in 161 hospitals met inclusion criteria. Crude hazards peaked initially, then steadily declined. When hazard ratios were assumed constant in HR models, they were similar to odds ratios in LR models associating increased mortality with increased age, firearm mechanism, increased severity, more deranged physiology, and estimated hospital-specific effects. However, when hospital effects were allowed to vary by time, HR models demonstrated that hospital outliers were not the same at different times after injury. Conclusions HR models with time-varying hazard ratios reveal inconsistencies in treatment effects, data quality, and/or timing of early death among trauma centers. HR models are generally more flexible than LR models, can be adapted for censored data, and potentially offer a better tool for analysis of factors affecting early death after injury. PMID:23036828

Hazard Function Estimation with Cause-of-Death Data Missing at Random

PubMed Central

Wang, Qihua; Dinse, Gregg E.; Liu, Chunling

2010-01-01

Hazard function estimation is an important part of survival analysis. Interest often centers on estimating the hazard function associated with a particular cause of death. We propose three nonparametric kernel estimators for the hazard function, all of which are appropriate when death times are subject to random censorship and censoring indicators can be missing at random. Specifically, we present a regression surrogate estimator, an imputation estimator, and an inverse probability weighted estimator. All three estimators are uniformly strongly consistent and asymptotically normal. We derive asymptotic representations of the mean squared error and the mean integrated squared error for these estimators and we discuss a data-driven bandwidth selection method. A simulation study, conducted to assess finite sample behavior, demonstrates that the proposed hazard estimators perform relatively well. We illustrate our methods with an analysis of some vascular disease data. PMID:22267874

Regression Discontinuity Designs in Epidemiology

PubMed Central

Moscoe, Ellen; Mutevedzi, Portia; Newell, Marie-Louise; Bärnighausen, Till

2014-01-01

When patients receive an intervention based on whether they score below or above some threshold value on a continuously measured random variable, the intervention will be randomly assigned for patients close to the threshold. The regression discontinuity design exploits this fact to estimate causal treatment effects. In spite of its recent proliferation in economics, the regression discontinuity design has not been widely adopted in epidemiology. We describe regression discontinuity, its implementation, and the assumptions required for causal inference. We show that regression discontinuity is generalizable to the survival and nonlinear models that are mainstays of epidemiologic analysis. We then present an application of regression discontinuity to the much-debated epidemiologic question of when to start HIV patients on antiretroviral therapy. Using data from a large South African cohort (2007–2011), we estimate the causal effect of early versus deferred treatment eligibility on mortality. Patients whose first CD4 count was just below the 200 cells/μL CD4 count threshold had a 35% lower hazard of death (hazard ratio = 0.65 [95% confidence interval = 0.45–0.94]) than patients presenting with CD4 counts just above the threshold. We close by discussing the strengths and limitations of regression discontinuity designs for epidemiology. PMID:25061922

[Application of SAS macro to evaluated multiplicative and additive interaction in logistic and Cox regression in clinical practices].

PubMed

Nie, Z Q; Ou, Y Q; Zhuang, J; Qu, Y J; Mai, J Z; Chen, J M; Liu, X Q

2016-05-01

Conditional logistic regression analysis and unconditional logistic regression analysis are commonly used in case control study, but Cox proportional hazard model is often used in survival data analysis. Most literature only refer to main effect model, however, generalized linear model differs from general linear model, and the interaction was composed of multiplicative interaction and additive interaction. The former is only statistical significant, but the latter has biological significance. In this paper, macros was written by using SAS 9.4 and the contrast ratio, attributable proportion due to interaction and synergy index were calculated while calculating the items of logistic and Cox regression interactions, and the confidence intervals of Wald, delta and profile likelihood were used to evaluate additive interaction for the reference in big data analysis in clinical epidemiology and in analysis of genetic multiplicative and additive interactions.

Optimizing the time-frame for the definition of bleeding-related death after acute variceal bleeding in cirrhosis.

PubMed

Merkel, C; Gatta, A; Bellumat, A; Bolognesi, M; Borsato, L; Caregaro, L; Cavallarin, G; Cielo, R; Cristina, P; Cucci, E; Donada, C; Donadon, V; Enzo, E; Martin, R; Mazzaro, C; Sacerdoti, D; Torboli, P

1996-01-01

To identify the best time-frame for defining bleeding-related death after variceal bleeding in patients with cirrhosis. Prospective long-term evaluation of a cohort of 155 patients admitted with variceal bleeding. Eight medical departments in seven hospitals in north-eastern Italy. Non-linear regression analysis of a hazard curve for death, and Cox's multiple regression analyses using different zero-time points. Cumulative hazard plots gave two slopes, the first corresponding to the risk of death from acute bleeding, the second a baseline risk of death. The first 30 days were outside the confidence limits of the regression curve for the baseline risk of death. Using Cox's regression analysis, the significant predictors of overall mortality risk were balanced between factors related to severity of bleeding and those related to severity of liver disease. If only deaths occurring after 30 days were considered, only predictors related to the severity of liver disease were found to be of importance. Thirty days after bleeding is considered to be a reasonable time-frame for the definition of bleeding-related death in patients with cirrhosis and variceal bleeding.

Updated logistic regression equations for the calculation of post-fire debris-flow likelihood in the western United States

USGS Publications Warehouse

Staley, Dennis M.; Negri, Jacquelyn A.; Kean, Jason W.; Laber, Jayme L.; Tillery, Anne C.; Youberg, Ann M.

2016-06-30

Wildfire can significantly alter the hydrologic response of a watershed to the extent that even modest rainstorms can generate dangerous flash floods and debris flows. To reduce public exposure to hazard, the U.S. Geological Survey produces post-fire debris-flow hazard assessments for select fires in the western United States. We use publicly available geospatial data describing basin morphology, burn severity, soil properties, and rainfall characteristics to estimate the statistical likelihood that debris flows will occur in response to a storm of a given rainfall intensity. Using an empirical database and refined geospatial analysis methods, we defined new equations for the prediction of debris-flow likelihood using logistic regression methods. We showed that the new logistic regression model outperformed previous models used to predict debris-flow likelihood.

Regression dilution in the proportional hazards model.

PubMed

Hughes, M D

1993-12-01

The problem of regression dilution arising from covariate measurement error is investigated for survival data using the proportional hazards model. The naive approach to parameter estimation is considered whereby observed covariate values are used, inappropriately, in the usual analysis instead of the underlying covariate values. A relationship between the estimated parameter in large samples and the true parameter is obtained showing that the bias does not depend on the form of the baseline hazard function when the errors are normally distributed. With high censorship, adjustment of the naive estimate by the factor 1 + lambda, where lambda is the ratio of within-person variability about an underlying mean level to the variability of these levels in the population sampled, removes the bias. As censorship increases, the adjustment required increases and when there is no censorship is markedly higher than 1 + lambda and depends also on the true risk relationship.

Chicken barn climate and hazardous volatile compounds control using simple linear regression and PID

NASA Astrophysics Data System (ADS)

Abdullah, A. H.; Bakar, M. A. A.; Shukor, S. A. A.; Saad, F. S. A.; Kamis, M. S.; Mustafa, M. H.; Khalid, N. S.

2016-07-01

The hazardous volatile compounds from chicken manure in chicken barn are potentially to be a health threat to the farm animals and workers. Ammonia (NH3) and hydrogen sulphide (H2S) produced in chicken barn are influenced by climate changes. The Electronic Nose (e-nose) is used for the barn's air, temperature and humidity data sampling. Simple Linear Regression is used to identify the correlation between temperature-humidity, humidity-ammonia and ammonia-hydrogen sulphide. MATLAB Simulink software was used for the sample data analysis using PID controller. Results shows that the performance of PID controller using the Ziegler-Nichols technique can improve the system controller to control climate in chicken barn.

Regional danger assessment of Debris flow and its engineering mitigation practice in Sichuan-Tibet highway

NASA Astrophysics Data System (ADS)

Su, Pengcheng; Sun, Zhengchao; li, Yong

2017-04-01

Luding-Kangding highway cross the eastern edge of Qinghai-Tibet Plateau where belong to the most deep canyon area of plateau and mountains in western Sichuan with high mountain and steep slope. This area belongs to the intersection among Xianshuihe, Longmenshan and Anninghe fault zones which are best known in Sichuan province. In the region, seismic intensity is with high frequency and strength, new tectonic movement is strong, rock is cracked, there are much loose solid materials. Debris flow disaster is well developed under the multiple effects of the earthquake, strong rainfall and human activity which poses a great threat to the local people's life and property security. So this paper chooses Kangding and LuDing as the study area to do the debris flow hazard assessment through the in-depth analysis of development characteristics and formation mechanism of debris flow. Which can provide important evidence for local disaster assessment and early warning forecast. It also has the important scientific significance and practical value to safeguard the people's life and property safety and the security implementation of the national major project. In this article, occurrence mechanism of debris flow disasters in the study area is explored, factor of evaluation with high impact to debris flow hazards is identified, the database of initial evaluation factors is made by the evaluation unit of basin. The factors with high impact to hazards occurrence are selected by using the stepwise regression method of logistic regression model, at the same time the factors with low impact are eliminated, then the hazard evaluation factor system of debris flow is determined in the study area. Then every factors of evaluation factor system are quantified, and the weights of all evaluation factors are determined by using the analysis of stepwise regression. The debris flows hazard assessment and regionalization of all the whole study area are achieved eventually after establishing the hazard assessment model. In this paper, regional debris flows hazard assessment method with strong universality and reliable evaluation result is presented. The whole study area is divided into 1674 units by automatically extracting and artificial identification, and then 11 factors are selected as the initial assessment factors of debris flow hazard assessment in the study area. The factors of the evaluation index system are quantified using the method of standardized watershed unit amount ratio. The relationship between debris flow occurrence and each evaluation factor is simulated using logistic regression model. The weights of evaluation factors are determined, and the model of debris flows hazard assessment is established in the study area. Danger assessment result of debris flow was applied in line optimization and engineering disaster reduction of Sichuan-Tibet highway (section of Luding-Kangding).

Revealing the underlying drivers of disaster risk: a global analysis

NASA Astrophysics Data System (ADS)

Peduzzi, Pascal

2017-04-01

Disasters events are perfect examples of compound events. Disaster risk lies at the intersection of several independent components such as hazard, exposure and vulnerability. Understanding the weight of each component requires extensive standardisation. Here, I show how footprints of past disastrous events were generated using GIS modelling techniques and used for extracting population and economic exposures based on distribution models. Using past event losses, it was possible to identify and quantify a wide range of socio-politico-economic drivers associated with human vulnerability. The analysis was applied to about nine thousand individual past disastrous events covering earthquakes, floods and tropical cyclones. Using a multiple regression analysis on these individual events it was possible to quantify each risk component and assess how vulnerability is influenced by various hazard intensities. The results show that hazard intensity, exposure, poverty, governance as well as other underlying factors (e.g. remoteness) can explain the magnitude of past disasters. Analysis was also performed to highlight the role of future trends in population and climate change and how this may impacts exposure to tropical cyclones in the future. GIS models combined with statistical multiple regression analysis provided a powerful methodology to identify, quantify and model disaster risk taking into account its various components. The same methodology can be applied to various types of risk at local to global scale. This method was applied and developed for the Global Risk Analysis of the Global Assessment Report on Disaster Risk Reduction (GAR). It was first applied on mortality risk in GAR 2009 and GAR 2011. New models ranging from global assets exposure and global flood hazard models were also recently developed to improve the resolution of the risk analysis and applied through CAPRA software to provide probabilistic economic risk assessments such as Average Annual Losses (AAL) and Probable Maximum Losses (PML) in GAR 2013 and GAR 2015. In parallel similar methodologies were developed to highlitght the role of ecosystems for Climate Change Adaptation (CCA) and Disaster Risk Reduction (DRR). New developments may include slow hazards (such as e.g. soil degradation and droughts), natech hazards (by intersecting with georeferenced critical infrastructures) The various global hazard, exposure and risk models can be visualized and download through the PREVIEW Global Risk Data Platform.

Logistic Regression in the Identification of Hazards in Construction

NASA Astrophysics Data System (ADS)

Drozd, Wojciech

2017-10-01

The construction site and its elements create circumstances that are conducive to the formation of risks to safety during the execution of works. Analysis indicates the critical importance of these factors in the set of characteristics that describe the causes of accidents in the construction industry. This article attempts to analyse the characteristics related to the construction site, in order to indicate their importance in defining the circumstances of accidents at work. The study includes sites inspected in 2014 - 2016 by the employees of the District Labour Inspectorate in Krakow (Poland). The analysed set of detailed (disaggregated) data includes both quantitative and qualitative characteristics. The substantive task focused on classification modelling in the identification of hazards in construction and identifying those of the analysed characteristics that are important in an accident. In terms of methodology, resource data analysis using statistical classifiers, in the form of logistic regression, was the method used.

Survival analysis: Part I — analysis of time-to-event

PubMed Central

2018-01-01

Length of time is a variable often encountered during data analysis. Survival analysis provides simple, intuitive results concerning time-to-event for events of interest, which are not confined to death. This review introduces methods of analyzing time-to-event. The Kaplan-Meier survival analysis, log-rank test, and Cox proportional hazards regression modeling method are described with examples of hypothetical data. PMID:29768911

Geospatial techniques for allocating vulnerability zoning of geohazards along the Karakorum Highway, Gilgit-Baltistan-Pakistan

NASA Astrophysics Data System (ADS)

Khan, K. M.; Rashid, S.; Yaseen, M.; Ikram, M.

2016-12-01

The Karakoram Highway (KKH) 'eighth wonder of the world', constructed and completed by the consent of Pakistan and China in 1979 as a Friendship Highway. It connect Gilgit-Baltistan, a strategically prominent region of Pakistan, with Xinjiang region in China. Due to manifold geology/geomorphology, soil formation, steep slopes, climate change well as unsustainable anthropogenic activities, still, KKH is remarkably vulnerable to natural hazards i.e. land subsistence, landslides, erosion, rock fall, floods, debris flows, cyclical torrential rainfall and snowfall, lake outburst etc. Most of the time these geohazard's damaging effects jeopardized the life in the region. To ascertain the nature and frequency of the disaster and vulnerability zoning, a rating and management (logistic) analysis were made to investigate the spatiotemporal sharing of the natural hazard. The substantial dynamics of the physiograpy, geology, geomorphology, soils and climate were carefully understand while slope, aspect, elevation, profile curvature and rock hardness was calculated by different techniques. To assess the nature and intensity geospatial analysis were conducted and magnitude of every factor was gauged by using logistic regression. Moreover, ever relative variable was integrated in the evaluation process. Logistic regression and geospatial techniques were used to map the geohazard vulnerability zoning (GVZ). The GVZ model findings were endorsed by the reviews of documented hazards in the current years and the precision was realized more than 88.1 %. The study has proved the model authentication by highlighting the comfortable indenture among the vulnerability mapping and past documented hazards. By using a receiver operating characteristic curve, the logistic regression model made satisfactory results. The outcomes will be useful in sustainable land use and infrastructure planning, mainly in high risk zones for reduceing economic damages and community betterment.

Vascular Disease, ESRD, and Death: Interpreting Competing Risk Analyses

PubMed Central

Coresh, Josef; Segev, Dorry L.; Kucirka, Lauren M.; Tighiouart, Hocine; Sarnak, Mark J.

2012-01-01

Summary Background and objectives Vascular disease, a common condition in CKD, is a risk factor for mortality and ESRD. Optimal patient care requires accurate estimation and ordering of these competing risks. Design, setting, participants, & measurements This is a prospective cohort study of screened (n=885) and randomized participants (n=837) in the Modification of Diet in Renal Disease study (original study enrollment, 1989–1992), evaluating the association of vascular disease with ESRD and pre-ESRD mortality using standard survival analysis and competing risk regression. Results The method of analysis resulted in markedly different estimates. Cumulative incidence by standard analysis (censoring at the competing event) implied that, with vascular disease, the 15-year incidence was 66% and 51% for ESRD and pre-ESRD death, respectively. A more accurate representation of absolute risk was estimated with competing risk regression: 15-year incidence was 54% and 29% for ESRD and pre-ESRD death, respectively. For the association of vascular disease with pre-ESRD death, estimates of relative risk by the two methods were similar (standard survival analysis adjusted hazard ratio, 1.63; 95% confidence interval, 1.20–2.20; competing risk regression adjusted subhazard ratio, 1.57; 95% confidence interval, 1.15–2.14). In contrast, the hazard and subhazard ratios differed substantially for other associations, such as GFR and pre-ESRD mortality. Conclusions When competing events exist, absolute risk is better estimated using competing risk regression, but etiologic associations by this method must be carefully interpreted. The presence of vascular disease in CKD decreases the likelihood of survival to ESRD, independent of age and other risk factors. PMID:22859747

Vascular disease, ESRD, and death: interpreting competing risk analyses.

PubMed

Grams, Morgan E; Coresh, Josef; Segev, Dorry L; Kucirka, Lauren M; Tighiouart, Hocine; Sarnak, Mark J

2012-10-01

Vascular disease, a common condition in CKD, is a risk factor for mortality and ESRD. Optimal patient care requires accurate estimation and ordering of these competing risks. This is a prospective cohort study of screened (n=885) and randomized participants (n=837) in the Modification of Diet in Renal Disease study (original study enrollment, 1989-1992), evaluating the association of vascular disease with ESRD and pre-ESRD mortality using standard survival analysis and competing risk regression. The method of analysis resulted in markedly different estimates. Cumulative incidence by standard analysis (censoring at the competing event) implied that, with vascular disease, the 15-year incidence was 66% and 51% for ESRD and pre-ESRD death, respectively. A more accurate representation of absolute risk was estimated with competing risk regression: 15-year incidence was 54% and 29% for ESRD and pre-ESRD death, respectively. For the association of vascular disease with pre-ESRD death, estimates of relative risk by the two methods were similar (standard survival analysis adjusted hazard ratio, 1.63; 95% confidence interval, 1.20-2.20; competing risk regression adjusted subhazard ratio, 1.57; 95% confidence interval, 1.15-2.14). In contrast, the hazard and subhazard ratios differed substantially for other associations, such as GFR and pre-ESRD mortality. When competing events exist, absolute risk is better estimated using competing risk regression, but etiologic associations by this method must be carefully interpreted. The presence of vascular disease in CKD decreases the likelihood of survival to ESRD, independent of age and other risk factors.

Survival analysis in hematologic malignancies: recommendations for clinicians

PubMed Central

Delgado, Julio; Pereira, Arturo; Villamor, Neus; López-Guillermo, Armando; Rozman, Ciril

2014-01-01

The widespread availability of statistical packages has undoubtedly helped hematologists worldwide in the analysis of their data, but has also led to the inappropriate use of statistical methods. In this article, we review some basic concepts of survival analysis and also make recommendations about how and when to perform each particular test using SPSS, Stata and R. In particular, we describe a simple way of defining cut-off points for continuous variables and the appropriate and inappropriate uses of the Kaplan-Meier method and Cox proportional hazard regression models. We also provide practical advice on how to check the proportional hazards assumption and briefly review the role of relative survival and multiple imputation. PMID:25176982

Intracoronary injection of CD34-cells in chronic ischemic heart failure: 7 years follow-up of the DanCell study.

PubMed

Hansen, Morten; Nyby, Sebastian; Eifer Møller, Jacob; Videbæk, Lars; Kassem, Moustapha; Barington, Torben; Thayssen, Per; Diederichsen, Axel Cosmus Pyndt

2014-01-01

Seven years ago, the DanCell study was carried out to test the hypothesis of improvement in left ventricular ejection fraction (LVEF) following repeated intracoronary injections of autologous bone marrow-derived stem cells (BMSCs) in patients suffering from chronic ischemic heart failure. In this post hoc analysis, the long-term effect of therapy is assessed. 32 patients [mean age 61 (SD ± 9), 81% males] with systolic dysfunction (LVEF 33 ± 9%) received two repeated intracoronary infusions (4 months apart) of autologous BMSCs (1,533 ± 765 × 10(6) BMSCs including 23 ± 11 × 10(6) CD34(+) cells and 14 ± 7 × 10(6) CD133(+) cells). Patients were followed for 7 years and deaths were recorded. During follow-up, 10 patients died (31%). In univariate regression analysis, the total number of BMSCs, CD34(+) cell count and CD133(+) cell count did not significantly correlate with survival (hazard ratio: 0.999, 95% CI: 0.998-1.000, p = 0.24; hazard ratio: 0.94, 95% CI: 0.88-1.01, p = 0.10, and hazard ratio: 0.96, 95% CI: 0.87-1.07, p = 0.47, respectively). After adjustment for baseline variables in multivariate regression analysis, the CD34(+) cell count was significantly associated with survival (hazard ratio: 0.90, 95% CI: 0.82-1.00, p = 0.04). Intracoronary injections of a high number of CD34(+) cells may have a beneficial effect on chronic ischemic heart failure in terms of long-term survival.

A long-recommended but seldom-used method of analysis for fall injuries found a unique pattern of risk factors in the youngest-old.

PubMed

Legrand, Helen; Pihlsgård, Mats; Nordell, Eva; Elmståhl, Sölve

2015-08-01

Few studies on fall risk factors use long-recommended methods for analysis of recurrent events. Previous falls are the biggest risk factor for future falls, but few fall studies focus on the youngest-old. This study's objective was to apply Cox regression for recurrent events to identify factors associated with injurious falls in the youngest-old. Participants were community-dwelling residents of southern Sweden (n = 1,133), aged 59-67 at baseline (median 61.2), from the youngest cohorts of the larger Good Aging in Skåne (GÅS) study. Exposure variable data were collected from baseline study visits and medical records. Injurious falls, defined as emergency, inpatient, or specialist visits associated with ICD-10 fall codes during the follow-up period (2001-2011), were gathered from national and regional registries. Analysis was conducted using time to event Cox Regression for recurrent events. A majority (77.1 %) of injurious falls caused serious injuries such as fractures and open wounds. Exposure to nervous system medications [hazard ratio (HR) 1.40, 95 % confidence interval (CI) 1.03-1.89], central nervous system disease (HR 1.79, CI 1.18-2.70), and previous injurious fall(s) (HR 2.00, CI 1.50-2.68) were associated with increased hazard of injurious fall. Regression for recurrent events is feasible with typical falls' study data. The association of certain exposures with increased hazard of injurious falls begins earlier than previously studied. Different patterns of risk factors by age can provide insight into the progression of frailty. Tailored fall prevention screening and intervention may be of value in populations younger than those traditionally screened.

Mixed effect Poisson log-linear models for clinical and epidemiological sleep hypnogram data

PubMed Central

Swihart, Bruce J.; Caffo, Brian S.; Crainiceanu, Ciprian; Punjabi, Naresh M.

2013-01-01

Bayesian Poisson log-linear multilevel models scalable to epidemiological studies are proposed to investigate population variability in sleep state transition rates. Hierarchical random effects are used to account for pairings of subjects and repeated measures within those subjects, as comparing diseased to non-diseased subjects while minimizing bias is of importance. Essentially, non-parametric piecewise constant hazards are estimated and smoothed, allowing for time-varying covariates and segment of the night comparisons. The Bayesian Poisson regression is justified through a re-derivation of a classical algebraic likelihood equivalence of Poisson regression with a log(time) offset and survival regression assuming exponentially distributed survival times. Such re-derivation allows synthesis of two methods currently used to analyze sleep transition phenomena: stratified multi-state proportional hazards models and log-linear models with GEE for transition counts. An example data set from the Sleep Heart Health Study is analyzed. Supplementary material includes the analyzed data set as well as the code for a reproducible analysis. PMID:22241689

Big Data Toolsets to Pharmacometrics: Application of Machine Learning for Time‐to‐Event Analysis

PubMed Central

Gong, Xiajing; Hu, Meng

2018-01-01

Abstract Additional value can be potentially created by applying big data tools to address pharmacometric problems. The performances of machine learning (ML) methods and the Cox regression model were evaluated based on simulated time‐to‐event data synthesized under various preset scenarios, i.e., with linear vs. nonlinear and dependent vs. independent predictors in the proportional hazard function, or with high‐dimensional data featured by a large number of predictor variables. Our results showed that ML‐based methods outperformed the Cox model in prediction performance as assessed by concordance index and in identifying the preset influential variables for high‐dimensional data. The prediction performances of ML‐based methods are also less sensitive to data size and censoring rates than the Cox regression model. In conclusion, ML‐based methods provide a powerful tool for time‐to‐event analysis, with a built‐in capacity for high‐dimensional data and better performance when the predictor variables assume nonlinear relationships in the hazard function. PMID:29536640

Bootstrap investigation of the stability of a Cox regression model.

PubMed

Altman, D G; Andersen, P K

1989-07-01

We describe a bootstrap investigation of the stability of a Cox proportional hazards regression model resulting from the analysis of a clinical trial of azathioprine versus placebo in patients with primary biliary cirrhosis. We have considered stability to refer both to the choice of variables included in the model and, more importantly, to the predictive ability of the model. In stepwise Cox regression analyses of 100 bootstrap samples using 17 candidate variables, the most frequently selected variables were those selected in the original analysis, and no other important variable was identified. Thus there was no reason to doubt the model obtained in the original analysis. For each patient in the trial, bootstrap confidence intervals were constructed for the estimated probability of surviving two years. It is shown graphically that these intervals are markedly wider than those obtained from the original model.

Ensemble of ground subsidence hazard maps using fuzzy logic

NASA Astrophysics Data System (ADS)

Park, Inhye; Lee, Jiyeong; Saro, Lee

2014-06-01

Hazard maps of ground subsidence around abandoned underground coal mines (AUCMs) in Samcheok, Korea, were constructed using fuzzy ensemble techniques and a geographical information system (GIS). To evaluate the factors related to ground subsidence, a spatial database was constructed from topographic, geologic, mine tunnel, land use, groundwater, and ground subsidence maps. Spatial data, topography, geology, and various ground-engineering data for the subsidence area were collected and compiled in a database for mapping ground-subsidence hazard (GSH). The subsidence area was randomly split 70/30 for training and validation of the models. The relationships between the detected ground-subsidence area and the factors were identified and quantified by frequency ratio (FR), logistic regression (LR) and artificial neural network (ANN) models. The relationships were used as factor ratings in the overlay analysis to create ground-subsidence hazard indexes and maps. The three GSH maps were then used as new input factors and integrated using fuzzy-ensemble methods to make better hazard maps. All of the hazard maps were validated by comparison with known subsidence areas that were not used directly in the analysis. As the result, the ensemble model was found to be more effective in terms of prediction accuracy than the individual model.

Survival Data and Regression Models

NASA Astrophysics Data System (ADS)

Grégoire, G.

2014-12-01

We start this chapter by introducing some basic elements for the analysis of censored survival data. Then we focus on right censored data and develop two types of regression models. The first one concerns the so-called accelerated failure time models (AFT), which are parametric models where a function of a parameter depends linearly on the covariables. The second one is a semiparametric model, where the covariables enter in a multiplicative form in the expression of the hazard rate function. The main statistical tool for analysing these regression models is the maximum likelihood methodology and, in spite we recall some essential results about the ML theory, we refer to the chapter "Logistic Regression" for a more detailed presentation.

A Tutorial on Multilevel Survival Analysis: Methods, Models and Applications

PubMed Central

Austin, Peter C.

2017-01-01

Summary Data that have a multilevel structure occur frequently across a range of disciplines, including epidemiology, health services research, public health, education and sociology. We describe three families of regression models for the analysis of multilevel survival data. First, Cox proportional hazards models with mixed effects incorporate cluster-specific random effects that modify the baseline hazard function. Second, piecewise exponential survival models partition the duration of follow-up into mutually exclusive intervals and fit a model that assumes that the hazard function is constant within each interval. This is equivalent to a Poisson regression model that incorporates the duration of exposure within each interval. By incorporating cluster-specific random effects, generalised linear mixed models can be used to analyse these data. Third, after partitioning the duration of follow-up into mutually exclusive intervals, one can use discrete time survival models that use a complementary log–log generalised linear model to model the occurrence of the outcome of interest within each interval. Random effects can be incorporated to account for within-cluster homogeneity in outcomes. We illustrate the application of these methods using data consisting of patients hospitalised with a heart attack. We illustrate the application of these methods using three statistical programming languages (R, SAS and Stata). PMID:29307954

A Tutorial on Multilevel Survival Analysis: Methods, Models and Applications.

PubMed

Austin, Peter C

2017-08-01

Data that have a multilevel structure occur frequently across a range of disciplines, including epidemiology, health services research, public health, education and sociology. We describe three families of regression models for the analysis of multilevel survival data. First, Cox proportional hazards models with mixed effects incorporate cluster-specific random effects that modify the baseline hazard function. Second, piecewise exponential survival models partition the duration of follow-up into mutually exclusive intervals and fit a model that assumes that the hazard function is constant within each interval. This is equivalent to a Poisson regression model that incorporates the duration of exposure within each interval. By incorporating cluster-specific random effects, generalised linear mixed models can be used to analyse these data. Third, after partitioning the duration of follow-up into mutually exclusive intervals, one can use discrete time survival models that use a complementary log-log generalised linear model to model the occurrence of the outcome of interest within each interval. Random effects can be incorporated to account for within-cluster homogeneity in outcomes. We illustrate the application of these methods using data consisting of patients hospitalised with a heart attack. We illustrate the application of these methods using three statistical programming languages (R, SAS and Stata).

Quantitative Analysis of {sup 18}F-Fluorodeoxyglucose Positron Emission Tomography Identifies Novel Prognostic Imaging Biomarkers in Locally Advanced Pancreatic Cancer Patients Treated With Stereotactic Body Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cui, Yi; Global Institution for Collaborative Research and Education, Hokkaido University, Sapporo; Song, Jie

Purpose: To identify prognostic biomarkers in pancreatic cancer using high-throughput quantitative image analysis. Methods and Materials: In this institutional review board–approved study, we retrospectively analyzed images and outcomes for 139 locally advanced pancreatic cancer patients treated with stereotactic body radiation therapy (SBRT). The overall population was split into a training cohort (n=90) and a validation cohort (n=49) according to the time of treatment. We extracted quantitative imaging characteristics from pre-SBRT {sup 18}F-fluorodeoxyglucose positron emission tomography, including statistical, morphologic, and texture features. A Cox proportional hazard regression model was built to predict overall survival (OS) in the training cohort using 162more » robust image features. To avoid over-fitting, we applied the elastic net to obtain a sparse set of image features, whose linear combination constitutes a prognostic imaging signature. Univariate and multivariate Cox regression analyses were used to evaluate the association with OS, and concordance index (CI) was used to evaluate the survival prediction accuracy. Results: The prognostic imaging signature included 7 features characterizing different tumor phenotypes, including shape, intensity, and texture. On the validation cohort, univariate analysis showed that this prognostic signature was significantly associated with OS (P=.002, hazard ratio 2.74), which improved upon conventional imaging predictors including tumor volume, maximum standardized uptake value, and total legion glycolysis (P=.018-.028, hazard ratio 1.51-1.57). On multivariate analysis, the proposed signature was the only significant prognostic index (P=.037, hazard ratio 3.72) when adjusted for conventional imaging and clinical factors (P=.123-.870, hazard ratio 0.53-1.30). In terms of CI, the proposed signature scored 0.66 and was significantly better than competing prognostic indices (CI 0.48-0.64, Wilcoxon rank sum test P<1e-6). Conclusion: Quantitative analysis identified novel {sup 18}F-fluorodeoxyglucose positron emission tomography image features that showed improved prognostic value over conventional imaging metrics. If validated in large, prospective cohorts, the new prognostic signature might be used to identify patients for individualized risk-adaptive therapy.« less

A Quasi-Experiment To Study the Impact of Vancomycin Area under the Concentration-Time Curve-Guided Dosing on Vancomycin-Associated Nephrotoxicity

PubMed Central

Finch, Natalie A.; Zasowski, Evan J.; Murray, Kyle P.; Mynatt, Ryan P.; Zhao, Jing J.; Yost, Raymond; Pogue, Jason M.

2017-01-01

ABSTRACT Evidence suggests that maintenance of vancomycin trough concentrations at between 15 and 20 mg/liter, as currently recommended, is frequently unnecessary to achieve the daily area under the concentration-time curve (AUC24) target of ≥400 mg · h/liter. Many patients with trough concentrations in this range have AUC24 values in excess of the therapeutic threshold and within the exposure range associated with nephrotoxicity. On the basis of this, the Detroit Medical Center switched from trough concentration-guided dosing to AUC-guided dosing to minimize potentially unnecessary vancomycin exposure. The primary objective of this analysis was to assess the impact of this intervention on vancomycin-associated nephrotoxicity in a single-center, retrospective quasi-experiment of hospitalized adult patients receiving intravenous vancomycin from 2014 to 2015. The primary analysis compared the incidence of nephrotoxicity between patients monitored by assessment of the AUC24 and those monitored by assessment of the trough concentration. Multivariable logistic and Cox proportional hazards regression examined the independent association between the monitoring strategy and nephrotoxicity. Secondary analysis compared vancomycin exposures (total daily dose, AUC, and trough concentrations) between monitoring strategies. Overall, 1,280 patients were included in the analysis. After adjusting for severity of illness, comorbidity, duration of vancomycin therapy, and concomitant receipt of nephrotoxins, AUC-guided dosing was independently associated with lower nephrotoxicity by both logistic regression (odds ratio, 0.52; 95% confidence interval [CI], 0.34 to 0.80; P = 0.003) and Cox proportional hazards regression (hazard ratio, 0.53; 95% CI, 0.35 to 0.78; P = 0.002). AUC-guided dosing was associated with lower total daily vancomycin doses, AUC values, and trough concentrations. Vancomycin AUC-guided dosing was associated with reduced nephrotoxicity, which appeared to be a result of reduced vancomycin exposure. PMID:28923869

A Quasi-Experiment To Study the Impact of Vancomycin Area under the Concentration-Time Curve-Guided Dosing on Vancomycin-Associated Nephrotoxicity.

PubMed

Finch, Natalie A; Zasowski, Evan J; Murray, Kyle P; Mynatt, Ryan P; Zhao, Jing J; Yost, Raymond; Pogue, Jason M; Rybak, Michael J

2017-12-01

Evidence suggests that maintenance of vancomycin trough concentrations at between 15 and 20 mg/liter, as currently recommended, is frequently unnecessary to achieve the daily area under the concentration-time curve (AUC 24 ) target of ≥400 mg · h/liter. Many patients with trough concentrations in this range have AUC 24 values in excess of the therapeutic threshold and within the exposure range associated with nephrotoxicity. On the basis of this, the Detroit Medical Center switched from trough concentration-guided dosing to AUC-guided dosing to minimize potentially unnecessary vancomycin exposure. The primary objective of this analysis was to assess the impact of this intervention on vancomycin-associated nephrotoxicity in a single-center, retrospective quasi-experiment of hospitalized adult patients receiving intravenous vancomycin from 2014 to 2015. The primary analysis compared the incidence of nephrotoxicity between patients monitored by assessment of the AUC 24 and those monitored by assessment of the trough concentration. Multivariable logistic and Cox proportional hazards regression examined the independent association between the monitoring strategy and nephrotoxicity. Secondary analysis compared vancomycin exposures (total daily dose, AUC, and trough concentrations) between monitoring strategies. Overall, 1,280 patients were included in the analysis. After adjusting for severity of illness, comorbidity, duration of vancomycin therapy, and concomitant receipt of nephrotoxins, AUC-guided dosing was independently associated with lower nephrotoxicity by both logistic regression (odds ratio, 0.52; 95% confidence interval [CI], 0.34 to 0.80; P = 0.003) and Cox proportional hazards regression (hazard ratio, 0.53; 95% CI, 0.35 to 0.78; P = 0.002). AUC-guided dosing was associated with lower total daily vancomycin doses, AUC values, and trough concentrations. Vancomycin AUC-guided dosing was associated with reduced nephrotoxicity, which appeared to be a result of reduced vancomycin exposure. Copyright © 2017 American Society for Microbiology.

The Breslow estimator of the nonparametric baseline survivor function in Cox's regression model: some heuristics.

PubMed

Hanley, James A

2008-01-01

Most survival analysis textbooks explain how the hazard ratio parameters in Cox's life table regression model are estimated. Fewer explain how the components of the nonparametric baseline survivor function are derived. Those that do often relegate the explanation to an "advanced" section and merely present the components as algebraic or iterative solutions to estimating equations. None comment on the structure of these estimators. This note brings out a heuristic representation that may help to de-mystify the structure.

Disaggregated seismic hazard and the elastic input energy spectrum: An approach to design earthquake selection

NASA Astrophysics Data System (ADS)

Chapman, Martin Colby

1998-12-01

The design earthquake selection problem is fundamentally probabilistic. Disaggregation of a probabilistic model of the seismic hazard offers a rational and objective approach that can identify the most likely earthquake scenario(s) contributing to hazard. An ensemble of time series can be selected on the basis of the modal earthquakes derived from the disaggregation. This gives a useful time-domain realization of the seismic hazard, to the extent that a single motion parameter captures the important time-domain characteristics. A possible limitation to this approach arises because most currently available motion prediction models for peak ground motion or oscillator response are essentially independent of duration, and modal events derived using the peak motions for the analysis may not represent the optimal characterization of the hazard. The elastic input energy spectrum is an alternative to the elastic response spectrum for these types of analyses. The input energy combines the elements of amplitude and duration into a single parameter description of the ground motion that can be readily incorporated into standard probabilistic seismic hazard analysis methodology. This use of the elastic input energy spectrum is examined. Regression analysis is performed using strong motion data from Western North America and consistent data processing procedures for both the absolute input energy equivalent velocity, (Vsbea), and the elastic pseudo-relative velocity response (PSV) in the frequency range 0.5 to 10 Hz. The results show that the two parameters can be successfully fit with identical functional forms. The dependence of Vsbea and PSV upon (NEHRP) site classification is virtually identical. The variance of Vsbea is uniformly less than that of PSV, indicating that Vsbea can be predicted with slightly less uncertainty as a function of magnitude, distance and site classification. The effects of site class are important at frequencies less than a few Hertz. The regression modeling does not resolve significant effects due to site class at frequencies greater than approximately 5 Hz. Disaggregation of general seismic hazard models using Vsbea indicates that the modal magnitudes for the higher frequency oscillators tend to be larger, and vary less with oscillator frequency, than those derived using PSV. Insofar as the elastic input energy may be a better parameter for quantifying the damage potential of ground motion, its use in probabilistic seismic hazard analysis could provide an improved means for selecting earthquake scenarios and establishing design earthquakes for many types of engineering analyses.

Use of partial least squares regression for the multivariate calibration of hazardous air pollutants in open-path FT-IR spectrometry

NASA Astrophysics Data System (ADS)

Hart, Brian K.; Griffiths, Peter R.

1998-06-01

Partial least squares (PLS) regression has been evaluated as a robust calibration technique for over 100 hazardous air pollutants (HAPs) measured by open path Fourier transform infrared (OP/FT-IR) spectrometry. PLS has the advantage over the current recommended calibration method of classical least squares (CLS), in that it can look at the whole useable spectrum (700-1300 cm-1, 2000-2150 cm-1, and 2400-3000 cm-1), and detect several analytes simultaneously. Up to one hundred HAPs synthetically added to OP/FT-IR backgrounds have been simultaneously calibrated and detected using PLS. PLS also has the advantage in requiring less preprocessing of spectra than that which is required in CLS calibration schemes, allowing PLS to provide user independent real-time analysis of OP/FT-IR spectra.

Pesticides in Urban Multiunit Dwellings: Hazard IdentificationUsing Classification and Regression Tree (CART) Analysis

EPA Science Inventory

Many units in public housing or other low-income urban dwellings may have elevated pesticide residues, given recurring infestation, but it would be logistically and economically infeasible to sample a large number of units to identify highly exposed households to design interven...

Parametric regression model for survival data: Weibull regression model as an example

PubMed Central

2016-01-01

Weibull regression model is one of the most popular forms of parametric regression model that it provides estimate of baseline hazard function, as well as coefficients for covariates. Because of technical difficulties, Weibull regression model is seldom used in medical literature as compared to the semi-parametric proportional hazard model. To make clinical investigators familiar with Weibull regression model, this article introduces some basic knowledge on Weibull regression model and then illustrates how to fit the model with R software. The SurvRegCensCov package is useful in converting estimated coefficients to clinical relevant statistics such as hazard ratio (HR) and event time ratio (ETR). Model adequacy can be assessed by inspecting Kaplan-Meier curves stratified by categorical variable. The eha package provides an alternative method to model Weibull regression model. The check.dist() function helps to assess goodness-of-fit of the model. Variable selection is based on the importance of a covariate, which can be tested using anova() function. Alternatively, backward elimination starting from a full model is an efficient way for model development. Visualization of Weibull regression model after model development is interesting that it provides another way to report your findings. PMID:28149846

Assessment of Uncertainties Related to Seismic Hazard Using Fuzzy Analysis

NASA Astrophysics Data System (ADS)

Jorjiashvili, N.; Yokoi, T.; Javakhishvili, Z.

2013-05-01

Seismic hazard analysis in last few decades has been become very important issue. Recently, new technologies and available data have been improved that helped many scientists to understand where and why earthquakes happen, physics of earthquakes, etc. They have begun to understand the role of uncertainty in Seismic hazard analysis. However, there is still significant problem how to handle existing uncertainty. The same lack of information causes difficulties to quantify uncertainty accurately. Usually attenuation curves are obtained in statistical way: regression analysis. Statistical and probabilistic analysis show overlapped results for the site coefficients. This overlapping takes place not only at the border between two neighboring classes, but also among more than three classes. Although the analysis starts from classifying sites using the geological terms, these site coefficients are not classified at all. In the present study, this problem is solved using Fuzzy set theory. Using membership functions the ambiguities at the border between neighboring classes can be avoided. Fuzzy set theory is performed for southern California by conventional way. In this study standard deviations that show variations between each site class obtained by Fuzzy set theory and classical way are compared. Results on this analysis show that when we have insufficient data for hazard assessment site classification based on Fuzzy set theory shows values of standard deviations less than obtained by classical way which is direct proof of less uncertainty.

Utilization of accident databases and fuzzy sets to estimate frequency of HazMat transport accidents.

PubMed

Qiao, Yuanhua; Keren, Nir; Mannan, M Sam

2009-08-15

Risk assessment and management of transportation of hazardous materials (HazMat) require the estimation of accident frequency. This paper presents a methodology to estimate hazardous materials transportation accident frequency by utilizing publicly available databases and expert knowledge. The estimation process addresses route-dependent and route-independent variables. Negative binomial regression is applied to an analysis of the Department of Public Safety (DPS) accident database to derive basic accident frequency as a function of route-dependent variables, while the effects of route-independent variables are modeled by fuzzy logic. The integrated methodology provides the basis for an overall transportation risk analysis, which can be used later to develop a decision support system.

Survival Analysis of Patients with End Stage Renal Disease

NASA Astrophysics Data System (ADS)

Urrutia, J. D.; Gayo, W. S.; Bautista, L. A.; Baccay, E. B.

2015-06-01

This paper provides a survival analysis of End Stage Renal Disease (ESRD) under Kaplan-Meier Estimates and Weibull Distribution. The data were obtained from the records of V. L. MakabaliMemorial Hospital with respect to time t (patient's age), covariates such as developed secondary disease (Pulmonary Congestion and Cardiovascular Disease), gender, and the event of interest: the death of ESRD patients. Survival and hazard rates were estimated using NCSS for Weibull Distribution and SPSS for Kaplan-Meier Estimates. These lead to the same conclusion that hazard rate increases and survival rate decreases of ESRD patient diagnosed with Pulmonary Congestion, Cardiovascular Disease and both diseases with respect to time. It also shows that female patients have a greater risk of death compared to males. The probability risk was given the equation R = 1 — e-H(t) where e-H(t) is the survival function, H(t) the cumulative hazard function which was created using Cox-Regression.

Plasma big endothelin-1 levels at admission and future cardiovascular outcomes: A cohort study in patients with stable coronary artery disease.

PubMed

Zhou, Bing-Yang; Guo, Yuan-Lin; Wu, Na-Qiong; Zhu, Cheng-Gang; Gao, Ying; Qing, Ping; Li, Xiao-Lin; Wang, Yao; Dong, Qian; Liu, Geng; Xu, Rui Xia; Cui, Chuan-Jue; Sun, Jing; Li, Jian-Jun

2017-03-01

Big endothelin-1 (ET-1) has been proposed as a novel prognostic indicator of acute coronary syndrome, while its predicting role of cardiovascular outcomes in patients with stable coronary artery disease (CAD) is unclear. A total of 3154 consecutive patients with stable CAD were enrolled and followed up for 24months. The outcomes included all-cause death, non-fatal myocardial infarction, stroke and unplanned revascularization (percutaneous coronary intervention and coronary artery bypass grafting). Baseline big ET-1 was measured using sandwich enzyme immunoassay method. Cox proportional hazard regression analysis and Kaplan-Meier analysis were used to evaluate the prognostic value of big ET-1 on cardiovascular outcomes. One hundred and eighty-nine (5.99%) events occurred during follow-up. Patients were divided into two groups: events group (n=189) and non-events group (n=2965). The results indicated that the events group had higher levels of big ET-1 compared to non-events group. Multivariable Cox proportional hazard regression analysis showed that big ET-1 was positively and statistically correlated with clinical outcomes (Hazard Ratio: 1.656, 95% confidence interval: 1.099-2.496, p=0.016). Additionally, the Kaplan-Meier analysis revealed that patients with higher big ET-1 presented lower event-free survival (p=0.016). The present study firstly suggests that big ET-1 is an independent risk marker of cardiovascular outcomes in patients with stable CAD. And more studies are needed to confirm our findings. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Beer drinking accounts for most of the hazardous alcohol consumption reported in the United States.

PubMed

Rogers, J D; Greenfield, T K

1999-11-01

Patterns and correlates of hazardous drinking, defined as occasions in which five or more drinks were consumed in a day, were compared for wine, beer and distilled spirits. From a probability sample of the U.S. adult household population, 2,817 respondents who had consumed at least one drink in the previous year were selected for analysis. The results show that, in the U.S., beer accounts for the bulk of alcohol consumed by the heaviest drinkers. Beer also accounts for a disproportionate share of hazardous drinking. Logistic regression analyses revealed that drinkers who consume beer in a hazardous fashion at least monthly are more likely to be young, male and unmarried, and less likely to be black than are other drinkers. Hazardous beer consumption is more predictive of alcohol-related problems than hazardous consumption of wine or spirits. Three potential explanations for the results are considered: advertising, beer-drinking subcultures and risk compensation. Additional research is urged in order to better specify the causal role of these and other factors in hazardous beer drinking.

Support vector methods for survival analysis: a comparison between ranking and regression approaches.

PubMed

Van Belle, Vanya; Pelckmans, Kristiaan; Van Huffel, Sabine; Suykens, Johan A K

2011-10-01

To compare and evaluate ranking, regression and combined machine learning approaches for the analysis of survival data. The literature describes two approaches based on support vector machines to deal with censored observations. In the first approach the key idea is to rephrase the task as a ranking problem via the concordance index, a problem which can be solved efficiently in a context of structural risk minimization and convex optimization techniques. In a second approach, one uses a regression approach, dealing with censoring by means of inequality constraints. The goal of this paper is then twofold: (i) introducing a new model combining the ranking and regression strategy, which retains the link with existing survival models such as the proportional hazards model via transformation models; and (ii) comparison of the three techniques on 6 clinical and 3 high-dimensional datasets and discussing the relevance of these techniques over classical approaches fur survival data. We compare svm-based survival models based on ranking constraints, based on regression constraints and models based on both ranking and regression constraints. The performance of the models is compared by means of three different measures: (i) the concordance index, measuring the model's discriminating ability; (ii) the logrank test statistic, indicating whether patients with a prognostic index lower than the median prognostic index have a significant different survival than patients with a prognostic index higher than the median; and (iii) the hazard ratio after normalization to restrict the prognostic index between 0 and 1. Our results indicate a significantly better performance for models including regression constraints above models only based on ranking constraints. This work gives empirical evidence that svm-based models using regression constraints perform significantly better than svm-based models based on ranking constraints. Our experiments show a comparable performance for methods including only regression or both regression and ranking constraints on clinical data. On high dimensional data, the former model performs better. However, this approach does not have a theoretical link with standard statistical models for survival data. This link can be made by means of transformation models when ranking constraints are included. Copyright © 2011 Elsevier B.V. All rights reserved.

Depression and incident dementia. An 8-year population-based prospective study.

PubMed

Luppa, Melanie; Luck, Tobias; Ritschel, Franziska; Angermeyer, Matthias C; Villringer, Arno; Riedel-Heller, Steffi G

2013-01-01

The aim of the study was to investigate the impact of depression (categorical diagnosis; major depression, MD) and depressive symptoms (dimensional diagnosis and symptom patterns) on incident dementia in the German general population. Within the Leipzig Longitudinal Study of the Aged (LEILA 75+), a representative sample of 1,265 individuals aged 75 years and older were interviewed every 1.5 years over 8 years (mean observation time 4.3 years; mean number of visits 4.2). Cox proportional hazards and binary logistic regressions were used to estimate the effect of baseline depression and depressive symptoms on incident dementia. The incidence of dementia was 48 per 1,000 person-years (95% confidence interval (CI) 45-51). Depressive symptoms (Hazard ratio HR 1.03, 95% CI 1.01-1.05), and in particular mood-related symptoms (HR 1.08, 95% CI 1.03-1.14), showed a significant impact on the incidence of dementia only in univariate analysis, but not after adjustment for cognitive and functional impairment. MD showed only a significant impact on incidence of dementia in Cox proportional hazards regression, but not in binary logistic regression models. The present study using different diagnostic measures of depression on future dementia found no clear significant associations of depression and incident dementia. Further in-depth investigation would help to understand the nature of depression in the context of incident dementia.

The effect of delayed graft function on graft and patient survival in kidney transplantation: an approach using competing events analysis.

PubMed

Fonseca, Isabel; Teixeira, Laetitia; Malheiro, Jorge; Martins, La Salete; Dias, Leonídio; Castro Henriques, António; Mendonça, Denisa

2015-06-01

In kidney transplantation, the impact of delayed graft function (DGF) on long-term graft and patient survival is controversial. We examined the impact of DGF on graft and recipient survival by accounting for the possibility that death with graft function may act as a competing risk for allograft failure. We used data from 1281 adult primary deceased-donor kidney recipients whose allografts functioned at least 1 year. The probability of graft loss occurrence is overestimated using the complement of Kaplan-Meier estimates (1-KM). Both the cause-specific Cox proportional hazard regression model (standard Cox) and the subdistribution hazard regression model proposed by Fine and Gray showed that DGF was associated with shorter time to graft failure (csHR = 2.0, P = 0.002; sHR = 1.57, P = 0.009), independent of acute rejection (AR) and after adjusting for traditional factors associated with graft failure. Regarding patient survival, DGF was a predictor of patient death using the cause-specific Cox model (csHR = 1.57, P = 0.029) but not using the subdistribution model. The probability of graft loss from competing end points should not be reported with the 1-KM. Application of a regression model for subdistribution hazard showed that, independent of AR, DGF has a detrimental effect on long-term graft survival, but not on patient survival. © 2015 Steunstichting ESOT.

Comparison of exact, efron and breslow parameter approach method on hazard ratio and stratified cox regression model

NASA Astrophysics Data System (ADS)

Fatekurohman, Mohamat; Nurmala, Nita; Anggraeni, Dian

2018-04-01

Lungs are the most important organ, in the case of respiratory system. Problems related to disorder of the lungs are various, i.e. pneumonia, emphysema, tuberculosis and lung cancer. Comparing all those problems, lung cancer is the most harmful. Considering about that, the aim of this research applies survival analysis and factors affecting the endurance of the lung cancer patient using comparison of exact, Efron and Breslow parameter approach method on hazard ratio and stratified cox regression model. The data applied are based on the medical records of lung cancer patients in Jember Paru-paru hospital on 2016, east java, Indonesia. The factors affecting the endurance of the lung cancer patients can be classified into several criteria, i.e. sex, age, hemoglobin, leukocytes, erythrocytes, sedimentation rate of blood, therapy status, general condition, body weight. The result shows that exact method of stratified cox regression model is better than other. On the other hand, the endurance of the patients is affected by their age and the general conditions.

Big Data Toolsets to Pharmacometrics: Application of Machine Learning for Time-to-Event Analysis.

PubMed

Gong, Xiajing; Hu, Meng; Zhao, Liang

2018-05-01

Additional value can be potentially created by applying big data tools to address pharmacometric problems. The performances of machine learning (ML) methods and the Cox regression model were evaluated based on simulated time-to-event data synthesized under various preset scenarios, i.e., with linear vs. nonlinear and dependent vs. independent predictors in the proportional hazard function, or with high-dimensional data featured by a large number of predictor variables. Our results showed that ML-based methods outperformed the Cox model in prediction performance as assessed by concordance index and in identifying the preset influential variables for high-dimensional data. The prediction performances of ML-based methods are also less sensitive to data size and censoring rates than the Cox regression model. In conclusion, ML-based methods provide a powerful tool for time-to-event analysis, with a built-in capacity for high-dimensional data and better performance when the predictor variables assume nonlinear relationships in the hazard function. © 2018 The Authors. Clinical and Translational Science published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

Practical application of cure mixture model for long-term censored survivor data from a withdrawal clinical trial of patients with major depressive disorder.

PubMed

Arano, Ichiro; Sugimoto, Tomoyuki; Hamasaki, Toshimitsu; Ohno, Yuko

2010-04-23

Survival analysis methods such as the Kaplan-Meier method, log-rank test, and Cox proportional hazards regression (Cox regression) are commonly used to analyze data from randomized withdrawal studies in patients with major depressive disorder. However, unfortunately, such common methods may be inappropriate when a long-term censored relapse-free time appears in data as the methods assume that if complete follow-up were possible for all individuals, each would eventually experience the event of interest. In this paper, to analyse data including such a long-term censored relapse-free time, we discuss a semi-parametric cure regression (Cox cure regression), which combines a logistic formulation for the probability of occurrence of an event with a Cox proportional hazards specification for the time of occurrence of the event. In specifying the treatment's effect on disease-free survival, we consider the fraction of long-term survivors and the risks associated with a relapse of the disease. In addition, we develop a tree-based method for the time to event data to identify groups of patients with differing prognoses (cure survival CART). Although analysis methods typically adapt the log-rank statistic for recursive partitioning procedures, the method applied here used a likelihood ratio (LR) test statistic from a fitting of cure survival regression assuming exponential and Weibull distributions for the latency time of relapse. The method is illustrated using data from a sertraline randomized withdrawal study in patients with major depressive disorder. We concluded that Cox cure regression reveals facts on who may be cured, and how the treatment and other factors effect on the cured incidence and on the relapse time of uncured patients, and that cure survival CART output provides easily understandable and interpretable information, useful both in identifying groups of patients with differing prognoses and in utilizing Cox cure regression models leading to meaningful interpretations.

Classification of Large-Scale Remote Sensing Images for Automatic Identification of Health Hazards: Smoke Detection Using an Autologistic Regression Classifier.

PubMed

Wolters, Mark A; Dean, C B

2017-01-01

Remote sensing images from Earth-orbiting satellites are a potentially rich data source for monitoring and cataloguing atmospheric health hazards that cover large geographic regions. A method is proposed for classifying such images into hazard and nonhazard regions using the autologistic regression model, which may be viewed as a spatial extension of logistic regression. The method includes a novel and simple approach to parameter estimation that makes it well suited to handling the large and high-dimensional datasets arising from satellite-borne instruments. The methodology is demonstrated on both simulated images and a real application to the identification of forest fire smoke.

Hazardous alcohol consumption in non-aboriginal male inmates in New South Wales.

PubMed

Field, Courtney

2018-03-12

Purpose The purpose of this paper is to examine correlates and predictors of hazardous drinking behaviour, that may be considered evidence of generalised strain, in a sample of incarcerated non-Aboriginal males in New South Wales, Australia. Design/methodology/approach Data were collected from 283 non-Aboriginal male inmates as part of a larger epidemiological survey of inmates in NSW undertaken in 2015 by the Justice Health and Forensic Mental Health Network. Data relating to a range of social factors were selected with reference to relevant literature and assessed with regards their predictive value for scores from the Alcohol Use Disorders Identification Test (AUDIT). To facilitate regression analysis, variables were logically organised into historical factors or adult factors. Findings Almost all participants reported some history of alcohol consumption. Hazardous drinking was common among participants. While parental alcohol problems and adult drug use were the only correlates of AUDIT scores, parental misuse of alcohol was shown to be an important predictor of AUDIT scores in regression analysis. The role of parent gender was inconclusive. Previous incarceration as an adult, employment status, and drug use as an adult also predicted AUDIT scores. Originality/value Alcohol abuse is common among inmates and the use of alcohol is implicated in the commission of many offences. A better understanding of its genesis may inspire novel approaches to treatment, leading to improved health outcomes for inmates.

An overall strategy based on regression models to estimate relative survival and model the effects of prognostic factors in cancer survival studies.

PubMed

Remontet, L; Bossard, N; Belot, A; Estève, J

2007-05-10

Relative survival provides a measure of the proportion of patients dying from the disease under study without requiring the knowledge of the cause of death. We propose an overall strategy based on regression models to estimate the relative survival and model the effects of potential prognostic factors. The baseline hazard was modelled until 10 years follow-up using parametric continuous functions. Six models including cubic regression splines were considered and the Akaike Information Criterion was used to select the final model. This approach yielded smooth and reliable estimates of mortality hazard and allowed us to deal with sparse data taking into account all the available information. Splines were also used to model simultaneously non-linear effects of continuous covariates and time-dependent hazard ratios. This led to a graphical representation of the hazard ratio that can be useful for clinical interpretation. Estimates of these models were obtained by likelihood maximization. We showed that these estimates could be also obtained using standard algorithms for Poisson regression. Copyright 2006 John Wiley & Sons, Ltd.

Adjusted variable plots for Cox's proportional hazards regression model.

PubMed

Hall, C B; Zeger, S L; Bandeen-Roche, K J

1996-01-01

Adjusted variable plots are useful in linear regression for outlier detection and for qualitative evaluation of the fit of a model. In this paper, we extend adjusted variable plots to Cox's proportional hazards model for possibly censored survival data. We propose three different plots: a risk level adjusted variable (RLAV) plot in which each observation in each risk set appears, a subject level adjusted variable (SLAV) plot in which each subject is represented by one point, and an event level adjusted variable (ELAV) plot in which the entire risk set at each failure event is represented by a single point. The latter two plots are derived from the RLAV by combining multiple points. In each point, the regression coefficient and standard error from a Cox proportional hazards regression is obtained by a simple linear regression through the origin fit to the coordinates of the pictured points. The plots are illustrated with a reanalysis of a dataset of 65 patients with multiple myeloma.

Safety training priorities

NASA Astrophysics Data System (ADS)

Thompson, N. A.; Ruck, H. W.

1984-04-01

The Air Force is interested in identifying potentially hazardous tasks and prevention of accidents. This effort proposes four methods for determining safety training priorities for job tasks in three enlisted specialties. These methods can be used to design training aimed at avoiding loss of people, time, materials, and money associated with on-the-job accidents. Job tasks performed by airmen were measured using task and job factor ratings. Combining accident reports and job inventories, subject-matter experts identified tasks associated with accidents over a 3-year period. Applying correlational, multiple regression, and cost-benefit analysis, four methods were developed for ordering hazardous tasks to determine safety training priorities.

Psychosocial Correlates of AUDIT-C Hazardous Drinking Risk Status: Implications for Screening and Brief Intervention in College Settings.

PubMed

Wahesh, Edward; Lewis, Todd F

2015-01-01

The current study identified psychosocial variables associated with AUDIT-C hazardous drinking risk status for male and female college students. Logistic regression analysis revealed that AUDIT-C risk status was associated with alcohol-related negative consequences, injunctive norms, and descriptive norms for both male and female participants. Sociability and self-perception outcome expectancies predicted risk status for females. Cognitive and behavioral impairment expectancies predicted risk status for men in the sample. Implications for screening and brief intervention programming efforts are discussed. © The Author(s) 2015.

Methodologies for the assessment of earthquake-triggered landslides hazard. A comparison of Logistic Regression and Artificial Neural Network models.

NASA Astrophysics Data System (ADS)

García-Rodríguez, M. J.; Malpica, J. A.; Benito, B.

2009-04-01

In recent years, interest in landslide hazard assessment studies has increased substantially. They are appropriate for evaluation and mitigation plan development in landslide-prone areas. There are several techniques available for landslide hazard research at a regional scale. Generally, they can be classified in two groups: qualitative and quantitative methods. Most of qualitative methods tend to be subjective, since they depend on expert opinions and represent hazard levels in descriptive terms. On the other hand, quantitative methods are objective and they are commonly used due to the correlation between the instability factors and the location of the landslides. Within this group, statistical approaches and new heuristic techniques based on artificial intelligence (artificial neural network (ANN), fuzzy logic, etc.) provide rigorous analysis to assess landslide hazard over large regions. However, they depend on qualitative and quantitative data, scale, types of movements and characteristic factors used. We analysed and compared an approach for assessing earthquake-triggered landslides hazard using logistic regression (LR) and artificial neural networks (ANN) with a back-propagation learning algorithm. One application has been developed in El Salvador, a country of Central America where the earthquake-triggered landslides are usual phenomena. In a first phase, we analysed the susceptibility and hazard associated to the seismic scenario of the 2001 January 13th earthquake. We calibrated the models using data from the landslide inventory for this scenario. These analyses require input variables representing physical parameters to contribute to the initiation of slope instability, for example, slope gradient, elevation, aspect, mean annual precipitation, lithology, land use, and terrain roughness, while the occurrence or non-occurrence of landslides is considered as dependent variable. The results of the landslide susceptibility analysis are checked using landslide location data. These results show a high concordance between the landslide inventory and the high susceptibility estimated zone with an adjustment of 95.1 % for ANN model and 89.4% for LR model. In addition, we make a comparative analysis of both techniques using the Receiver Operating Characteristic (ROC) curve, a graphical plot of the sensitivity vs. (1 - specificity) for a binary classifier system in function of its discrimination threshold, and calculating the Area Under the ROC (AUROC) value for each model. Finally, the previous models are used for the developing a new probabilistic landslide hazard map for future events. They are obtained combining the expected triggering factor (calculated earthquake ground motion) for a return period of 475 years with the susceptibility map.

Association Between Obstetric Mode of Delivery and Autism Spectrum Disorder: A Population-Based Sibling Design Study.

PubMed

Curran, Eileen A; Dalman, Christina; Kearney, Patricia M; Kenny, Louise C; Cryan, John F; Dinan, Timothy G; Khashan, Ali S

2015-09-01

Because the rates of cesarean section (CS) are increasing worldwide, it is becoming increasingly important to understand the long-term effects that mode of delivery may have on child development. To investigate the association between obstetric mode of delivery and autism spectrum disorder (ASD). Perinatal factors and ASD diagnoses based on the International Classification of Diseases, Ninth Revision (ICD-9),and the International Statistical Classification of Diseases, 10th Revision (ICD-10),were identified from the Swedish Medical Birth Register and the Swedish National Patient Register. We conducted stratified Cox proportional hazards regression analysis to examine the effect of mode of delivery on ASD. We then used conditional logistic regression to perform a sibling design study, which consisted of sibling pairs discordant on ASD status. Analyses were adjusted for year of birth (ie, partially adjusted) and then fully adjusted for various perinatal and sociodemographic factors. The population-based cohort study consisted of all singleton live births in Sweden from January 1, 1982, through December 31, 2010. Children were followed up until first diagnosis of ASD, death, migration, or December 31, 2011 (end of study period), whichever came first. The full cohort consisted of 2,697,315 children and 28,290 cases of ASD. Sibling control analysis consisted of 13,411 sibling pairs. Obstetric mode of delivery defined as unassisted vaginal delivery (VD), assisted VD, elective CS, and emergency CS (defined by before or after onset of labor). The ASD status as defined using codes from the ICD-9 (code 299) and ICD-10 (code F84). In adjusted Cox proportional hazards regression analysis, elective CS (hazard ratio, 1.21; 95% CI, 1.15-1.27) and emergency CS (hazard ratio, 1.15; 95% CI, 1.10-1.20) were associated with ASD when compared with unassisted VD. In the sibling control analysis, elective CS was not associated with ASD in partially (odds ratio [OR], 0.97; 95% CI, 0.85-1.11) or fully adjusted (OR, 0.89; 95% CI, 0.76-1.04) models. Emergency CS was significantly associated with ASD in partially adjusted analysis (OR, 1.20; 95% CI, 1.06-1.36), but this effect disappeared in the fully adjusted model (OR, 0.97; 95% CI, 0.85-1.11). This study confirms previous findings that children born by CS are approximately 20% more likely to be diagnosed as having ASD. However, the association did not persist when using sibling controls, implying that this association is due to familial confounding by genetic and/or environmental factors.

Association between Stereotactic Radiotherapy and Death from Brain Metastases of Epithelial Ovarian Cancer: a Gliwice Data Re-Analysis with Penalization

PubMed

Tukiendorf, Andrzej; Mansournia, Mohammad Ali; Wydmański, Jerzy; Wolny-Rokicka, Edyta

2017-04-01

Background: Clinical datasets for epithelial ovarian cancer brain metastatic patients are usually small in size. When adequate case numbers are lacking, resulting estimates of regression coefficients may demonstrate bias. One of the direct approaches to reduce such sparse-data bias is based on penalized estimation. Methods: A re- analysis of formerly reported hazard ratios in diagnosed patients was performed using penalized Cox regression with a popular SAS package providing additional software codes for a statistical computational procedure. Results: It was found that the penalized approach can readily diminish sparse data artefacts and radically reduce the magnitude of estimated regression coefficients. Conclusions: It was confirmed that classical statistical approaches may exaggerate regression estimates or distort study interpretations and conclusions. The results support the thesis that penalization via weak informative priors and data augmentation are the safest approaches to shrink sparse data artefacts frequently occurring in epidemiological research. Creative Commons Attribution License

Estimation of variance in Cox's regression model with shared gamma frailties.

PubMed

Andersen, P K; Klein, J P; Knudsen, K M; Tabanera y Palacios, R

1997-12-01

The Cox regression model with a shared frailty factor allows for unobserved heterogeneity or for statistical dependence between the observed survival times. Estimation in this model when the frailties are assumed to follow a gamma distribution is reviewed, and we address the problem of obtaining variance estimates for regression coefficients, frailty parameter, and cumulative baseline hazards using the observed nonparametric information matrix. A number of examples are given comparing this approach with fully parametric inference in models with piecewise constant baseline hazards.

Doubly Robust Additive Hazards Models to Estimate Effects of a Continuous Exposure on Survival.

PubMed

Wang, Yan; Lee, Mihye; Liu, Pengfei; Shi, Liuhua; Yu, Zhi; Abu Awad, Yara; Zanobetti, Antonella; Schwartz, Joel D

2017-11-01

The effect of an exposure on survival can be biased when the regression model is misspecified. Hazard difference is easier to use in risk assessment than hazard ratio and has a clearer interpretation in the assessment of effect modifications. We proposed two doubly robust additive hazards models to estimate the causal hazard difference of a continuous exposure on survival. The first model is an inverse probability-weighted additive hazards regression. The second model is an extension of the doubly robust estimator for binary exposures by categorizing the continuous exposure. We compared these with the marginal structural model and outcome regression with correct and incorrect model specifications using simulations. We applied doubly robust additive hazard models to the estimation of hazard difference of long-term exposure to PM2.5 (particulate matter with an aerodynamic diameter less than or equal to 2.5 microns) on survival using a large cohort of 13 million older adults residing in seven states of the Southeastern United States. We showed that the proposed approaches are doubly robust. We found that each 1 μg m increase in annual PM2.5 exposure was associated with a causal hazard difference in mortality of 8.0 × 10 (95% confidence interval 7.4 × 10, 8.7 × 10), which was modified by age, medical history, socioeconomic status, and urbanicity. The overall hazard difference translates to approximately 5.5 (5.1, 6.0) thousand deaths per year in the study population. The proposed approaches improve the robustness of the additive hazards model and produce a novel additive causal estimate of PM2.5 on survival and several additive effect modifications, including social inequality.

Predictors of hazardous drinking, tobacco smoking and physical inactivity in vocational school students

PubMed Central

2013-01-01

Background Tobacco smoking, hazardous drinking and physical inactivity during adolescence are risk factors that are associated with poorer health in adulthood. The identification of subgroups of young people with a high prevalence of one or more of these risk factors allows an optimised allocation of preventive measures. This study aimed at investigating hazardous drinking, tobacco smoking and physical inactivity as well as their associations and demographic predictors in vocational school students. Methods Out of 57 contacted vocational schools in Switzerland, a total of 24 schools participated in a survey assessing gender, age, immigrant background, educational attainment and vocational field as well as the above mentioned health risk factors. Out of the 2659 students present in 177 included vocational school classes, 2647 (99.5%) completed the survey. Binary logistic regression analyses were conducted to investigate the demographic predictors of each health risk factor and a multinomial logistic regression analysis was conducted to investigate predictors of different risk factor combinations. Results Of the surveyed students, 79.4% showed at least one risk factor, 43.6% showed two or more and 9.6% showed all three health risk factors. Hazardous drinking was more prevalent in male, physical inactivity was more prevalent in female vocational school students. The proportion of students with low physical activity and tobacco smoking increased with increasing age. While the combination of hazardous drinking and tobacco smoking was higher in males, the other risk factor combinations were observed particularly among females. Conclusions Multiple risk factors were ascertained in a significant proportion of vocational school students. Specifically, tobacco smoking and hazardous drinking were coexistent. The study underlines the need for preventive measures in specific subpopulations of adolescents and young adults with lower educational level. PMID:23672294

A difference in systolic blood pressure between arms is a novel predictor of the development and progression of diabetic nephropathy in patients with type 2 diabetes.

PubMed

Okada, Hiroshi; Fukui, Michiaki; Tanaka, Muhei; Matsumoto, Shinobu; Iwase, Hiroya; Kobayashi, Kanae; Asano, Mai; Yamazaki, Masahiro; Hasegawa, Goji; Nakamura, Naoto

2013-10-01

Recent studies have suggested that a difference in systolic blood pressure (SBP) between arms is associated with both vascular disease and mortality. The aim of this study was to investigate the relationship between a difference in SBP between arms and change in urinary albumin excretion or development of albuminuria in patients with type 2 diabetes. We measured SBP in 408 consecutive patients with type 2 diabetes, and calculated a difference in SBP between arms. We performed follow-up study to assess change in urinary albumin excretion or development of albuminuria, mean interval of which was 4.6 ± 1.7 years. We then evaluated the relationship of a difference in SBP between arms to diabetic nephropathy using multiple regression analysis and multiple Cox regression model. Multiple regression analyses demonstrated that a difference in SBP between arms was independently associated with change in urinary albumin excretion (β = 0.1869, P = 0.0010). Adjusted Cox regression analyses demonstrated that a difference in SBP between arms was associated with an increased hazard of development of albuminuria; hazard ratio was 1.215 (95% confidence interval 1.077-1.376). Moreover, the risk of development of albuminuria was increased in patients with a difference in SBP of equal to or more than 10 mmHg between arms; hazard ratio was 4.168 (95% confidence interval 1.478-11.70). A difference in SBP between arms could be a novel predictor of the development and progression of diabetic nephropathy in patients with type 2 diabetes. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The effect of preexisting respiratory co-morbidities on burn outcomes☆

PubMed Central

Knowlin, Laquanda T.; Stanford, Lindsay B.; Cairns, Bruce A.; Charles, Anthony G.

2018-01-01

Introduction Burns cause physiologic changes in multiple organ systems in the body. Burn mortality is usually attributable to pulmonary complications, which can occur in up to 41% of patients admitted to the hospital after burn. Patients with preexisting comorbidities such as chronic lung diseases may be more susceptible. We therefore sought to examine the impact of preexisting respiratory disease on burn outcomes. Methods A retrospective analysis of patients admitted to a regional burn center from 2002–2012. Independent variables analyzed included basic demographics, burn mechanism, presence of inhalation injury, TBSA, pre-existing comorbidities, smoker status, length of hospital stay, and days of mechanical ventilation. Bivariate analysis was performed and Cox regression modeling using significant variables was utilized to estimate hazard of progression to mechanical ventilation and mortality. Results There were a total of 7640 patients over the study period. Overall survival rate was 96%. 8% (n=672) had a preexisting respiratory disease. Chronic lung disease patients had a higher mortality rate (7%) compared to those without lung disease (4%, p<0.01). The adjusted Cox regression model to estimate the hazard of progression to mechanical ventilation in patients with respiratory disease was 21% higher compared to those without respiratory disease (HR=1.21, 95% CI=1.01–1.44). The hazard of progression to mortality is 56% higher (HR=1.56, 95% CI=1.10–2.19) for patients with pre-existing respiratory disease compared to those without respiratory disease after controlling for patient demographics and injury characteristics. Conclusion Preexisting chronic respiratory disease significantly increases the hazard of progression to mechanical ventilation and mortality in patients following burn. Given the increasing number of Americans with chronic respiratory diseases, there will likely be a greater number of individuals at risk for worse outcomes following burn. PMID:28341260

The effect of preexisting respiratory co-morbidities on burn outcomes.

PubMed

Knowlin, Laquanda T; Stanford, Lindsay B; Cairns, Bruce A; Charles, Anthony G

2017-03-01

Burns cause physiologic changes in multiple organ systems in the body. Burn mortality is usually attributable to pulmonary complications, which can occur in up to 41% of patients admitted to the hospital after burn. Patients with preexisting comorbidities such as chronic lung diseases may be more susceptible. We therefore sought to examine the impact of preexisting respiratory disease on burn outcomes. A retrospective analysis of patients admitted to a regional burn center from 2002-2012. Independent variables analyzed included basic demographics, burn mechanism, presence of inhalation injury, TBSA, pre-existing comorbidities, smoker status, length of hospital stay, and days of mechanical ventilation. Bivariate analysis was performed and Cox regression modeling using significant variables was utilized to estimate hazard of progression to mechanical ventilation and mortality. There were a total of 7640 patients over the study period. Overall survival rate was 96%. 8% (n=672) had a preexisting respiratory disease. Chronic lung disease patients had a higher mortality rate (7%) compared to those without lung disease (4%, p<0.01). The adjusted Cox regression model to estimate the hazard of progression to mechanical ventilation in patients with respiratory disease was 21% higher compared to those without respiratory disease (HR=1.21, 95% CI=1.01-1.44). The hazard of progression to mortality is 56% higher (HR=1.56, 95% CI=1.10-2.19) for patients with pre-existing respiratory disease compared to those without respiratory disease after controlling for patient demographics and injury characteristics. Preexisting chronic respiratory disease significantly increases the hazard of progression to mechanical ventilation and mortality in patients following burn. Given the increasing number of Americans with chronic respiratory diseases, there will likely be a greater number of individuals at risk for worse outcomes following burn. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Herpes zoster could be an early manifestation of undiagnosed human immunodeficiency virus infection.

PubMed

Lai, Shih-Wei; Lin, Cheng-Li; Liao, Kuan-Fu; Chen, Wen-Chi

2016-05-01

No formal epidemiological research based on systematic analysis has focused on the relationship between herpes zoster and immunodeficiency virus (HIV) infection in Taiwan. Our aim was to explore whether herpes zoster is an early manifestation of undiagnosed human HIV infection in Taiwan. This was a retrospective cohort study using the database of the Taiwan National Health Insurance Program. A total of 35,892 individuals aged ≤ 84 years with newly diagnosed herpes zoster from 1998 to 2010 were assigned to the herpes zoster group, whereas 143,568 sex-matched and age-matched, randomly selected individuals without herpes zoster served as the non-herpes zoster group. The incidence of HIV diagnosis at the end of 2011 was estimated in both groups. The multivariable Cox proportional hazards regression model was used to estimate the hazard ratio and 95% confidence interval (CI) for risk of HIV diagnosis associated with herpes zoster and other comorbidities including drug dependence and venereal diseases. The overall incidence of HIV diagnosis was 4.19-fold greater in the herpes zoster group than that in the non-herpes zoster group (3.33 per 10,000 person-years vs. 0.80 per 10,000 person-years, 95% CI 4.04-4.35). The multivariable Cox proportional hazards regression analysis revealed that the adjusted hazard ratio of HIV diagnosis was 4.37 (95% CI 3.10-6.15) for individuals with herpes zoster and without comorbidities, as compared with individuals without herpes zoster and without comorbidities. Herpes zoster is associated with HIV diagnosis. Patients who have risk behaviors of HIV infection should receive regular surveillance for undiagnosed HIV infection when they present with herpes zoster. Copyright © 2015. Published by Elsevier B.V.

Survival analysis of postoperative nausea and vomiting in patients receiving patient-controlled epidural analgesia.

PubMed

Lee, Shang-Yi; Hung, Chih-Jen; Chen, Chih-Chieh; Wu, Chih-Cheng

2014-11-01

Postoperative nausea and vomiting as well as postoperative pain are two major concerns when patients undergo surgery and receive anesthetics. Various models and predictive methods have been developed to investigate the risk factors of postoperative nausea and vomiting, and different types of preventive managements have subsequently been developed. However, there continues to be a wide variation in the previously reported incidence rates of postoperative nausea and vomiting. This may have occurred because patients were assessed at different time points, coupled with the overall limitation of the statistical methods used. However, using survival analysis with Cox regression, and thus factoring in these time effects, may solve this statistical limitation and reveal risk factors related to the occurrence of postoperative nausea and vomiting in the following period. In this retrospective, observational, uni-institutional study, we analyzed the results of 229 patients who received patient-controlled epidural analgesia following surgery from June 2007 to December 2007. We investigated the risk factors for the occurrence of postoperative nausea and vomiting, and also assessed the effect of evaluating patients at different time points using the Cox proportional hazards model. Furthermore, the results of this inquiry were compared with those results using logistic regression. The overall incidence of postoperative nausea and vomiting in our study was 35.4%. Using logistic regression, we found that only sex, but not the total doses and the average dose of opioids, had significant effects on the occurrence of postoperative nausea and vomiting at some time points. Cox regression showed that, when patients consumed a higher average dose of opioids, this correlated with a higher incidence of postoperative nausea and vomiting with a hazard ratio of 1.286. Survival analysis using Cox regression showed that the average consumption of opioids played an important role in postoperative nausea and vomiting, a result not found by logistic regression. Therefore, the incidence of postoperative nausea and vomiting in patients cannot be reliably determined on the basis of a single visit at one point in time. Copyright © 2014. Published by Elsevier Taiwan.

Prognostic value of the post-training oxygen uptake efficiency slope in patients with coronary artery disease.

PubMed

Buys, Roselien; Coeckelberghs, Ellen; Cornelissen, Véronique A; Goetschalckx, Kaatje; Vanhees, Luc

2016-09-01

Peak oxygen uptake is an independent predictor of mortality in patients with coronary artery disease (CAD). However, patients with CAD are not always capable of reaching peak effort, and therefore submaximal gas exchange variables such as the oxygen uptake efficiency slope (OUES) have been introduced. Baseline exercise capacity as expressed by OUES provides prognostic information and this parameter responds to training. Therefore, we aimed to assess the prognostic value of post-training OUES in patients with CAD. We included 960 patients with CAD (age 60.6 ± 9.5 years; 853 males) who completed a cardiac rehabilitation program between 2000 and 2011. The OUES was calculated before and after cardiac rehabilitation and information on mortality was obtained. The relationships of post-training OUES with all-cause and cardiovascular (CV) mortality was assessed by Cox proportional hazards regression analyses. Receiver operator characteristic curve analysis was performed in order to obtain the optimal cut-off value. During 7.37 ± 3.20 years of follow-up (range: 0.45-13.75 years), 108 patients died, among whom 47 died due to CV reasons. The post-training OUES was related to all-cause (hazard ratio: 0.50, p < 0.001) and CV (hazard ratio: 0.40, p < 0.001) mortality. When significant covariates, including baseline OUES, were entered into the Cox regression analysis, post-training OUES remained related to all-cause and CV mortality (hazard ratio: 0.40, p < 0.01 and 0.26, p < 0.01, respectively). In addition, the change in OUES due to exercise training was positively related to mortality (hazard ratio: 0.49, p < 0.01). Post-training OUES has stronger prognostic value compared to baseline OUES. The lack of improvement in exercise capacity expressed by OUES after an exercise training program relates to a worse prognosis and can help distinguish patients with favorable and unfavorable prognoses. © The European Society of Cardiology 2016.

The role of building models in the evaluation of heat-related risks

NASA Astrophysics Data System (ADS)

Buchin, Oliver; Jänicke, Britta; Meier, Fred; Scherer, Dieter; Ziegler, Felix

2016-04-01

Hazard-risk relationships in epidemiological studies are generally based on the outdoor climate, despite the fact that most of humans' lifetime is spent indoors. By coupling indoor and outdoor climates with a building model, the risk concept developed can still be based on the outdoor conditions but also includes exposure to the indoor climate. The influence of non-linear building physics and the impact of air conditioning on heat-related risks can be assessed in a plausible manner using this risk concept. For proof of concept, the proposed risk concept is compared to a traditional risk analysis. As an example, daily and city-wide mortality data of the age group 65 and older in Berlin, Germany, for the years 2001-2010 are used. Four building models with differing complexity are applied in a time-series regression analysis. This study shows that indoor hazard better explains the variability in the risk data compared to outdoor hazard, depending on the kind of building model. Simplified parameter models include the main non-linear effects and are proposed for the time-series analysis. The concept shows that the definitions of heat events, lag days, and acclimatization in a traditional hazard-risk relationship are influenced by the characteristics of the prevailing building stock.

Leucocyte telomere length and risk of type 2 diabetes mellitus: new prospective cohort study and literature-based meta-analysis.

PubMed

Willeit, Peter; Raschenberger, Julia; Heydon, Emma E; Tsimikas, Sotirios; Haun, Margot; Mayr, Agnes; Weger, Siegfried; Witztum, Joseph L; Butterworth, Adam S; Willeit, Johann; Kronenberg, Florian; Kiechl, Stefan

2014-01-01

Short telomeres have been linked to various age-related diseases. We aimed to assess the association of telomere length with incident type 2 diabetes mellitus (T2DM) in prospective cohort studies. Leucocyte relative telomere length (RTL) was measured using quantitative polymerase chain reaction in 684 participants of the prospective population-based Bruneck Study (1995 baseline), with repeat RTL measurements performed in 2005 (n = 558) and 2010 (n = 479). Hazard ratios for T2DM were calculated across quartiles of baseline RTL using Cox regression models adjusted for age, sex, body-mass index, smoking, socio-economic status, physical activity, alcohol consumption, high-density lipoprotein cholesterol, log high-sensitivity C-reactive protein, and waist-hip ratio. Separate analyses corrected hazard ratios for within-person variability using multivariate regression calibration of repeated measurements. To contextualise findings, we systematically sought PubMed, Web of Science and EMBASE for relevant articles and pooled results using random-effects meta-analysis. Over 15 years of follow-up, 44 out of 606 participants free of diabetes at baseline developed incident T2DM. The adjusted hazard ratio for T2DM comparing the bottom vs. the top quartile of baseline RTL (i.e. shortest vs. longest) was 2.00 (95% confidence interval: 0.90 to 4.49; P = 0.091), and 2.31 comparing the bottom quartile vs. the remainder (1.21 to 4.41; P = 0.011). The corresponding hazard ratios corrected for within-person RTL variability were 3.22 (1.27 to 8.14; P = 0.014) and 2.86 (1.45 to 5.65; P = 0.003). In a random-effects meta-analysis of three prospective cohort studies involving 6,991 participants and 2,011 incident T2DM events, the pooled relative risk was 1.31 (1.07 to 1.60; P = 0.010; I2 = 69%). Low RTL is independently associated with the risk of incident T2DM. To avoid regression dilution biases in observed associations of RTL with disease risk, future studies should implement methods correcting for within-person variability in RTL. The causal role of short telomeres in T2DM development remains to be determined.

Risk factors for acute chemical releases with public health consequences: Hazardous Substances Emergency Events Surveillance in the U.S., 1996–2001

PubMed Central

Ruckart, Perri Z; Wattigney, Wendy A; Kaye, Wendy E

2004-01-01

Background Releases of hazardous materials can cause substantial morbidity and mortality. To reduce and prevent the public health consequences (victims or evacuations) from uncontrolled or illegally released hazardous substances, a more comprehensive analysis is needed to determine risk factors for hazardous materials incidents. Methods Hazardous Substances Emergency Events Surveillance (HSEES) data from 1996 through 2001 were analyzed using bivariate and multiple logistic regression. Fixed-facility and transportation-related events were analyzed separately. Results For fixed-facility events, 2,327 (8%) resulted in at least one victim and 2,844 (10%) involved ordered evacuations. For transportation-related events, 759 (8%) resulted in at least one victim, and 405 (4%) caused evacuation orders. Fire and/or explosion were the strongest risk factors for events involving either victims or evacuations. Stratified analysis of fixed-facility events involving victims showed a strong association for acid releases in the agriculture, forestry, and fisheries industry. Chlorine releases in fixed-facility events resulted in victims and evacuations in more industry categories than any other substance. Conclusions Outreach efforts should focus on preventing and preparing for fires and explosions, acid releases in the agricultural industry, and chlorine releases in fixed facilities. PMID:15496226

Yonsei nomogram: A predictive model of new-onset chronic kidney disease after on-clamp partial nephrectomy in patients with T1 renal tumors.

PubMed

Abdel Raheem, Ali; Shin, Tae Young; Chang, Ki Don; Santok, Glen Denmer R; Alenzi, Mohamed Jayed; Yoon, Young Eun; Ham, Won Sik; Han, Woong Kyu; Choi, Young Deuk; Rha, Koon Ho

2018-06-19

To develop a predictive nomogram for chronic kidney disease-free survival probability in the long term after partial nephrectomy. A retrospective analysis was carried out of 698 patients with T1 renal tumors undergoing partial nephrectomy at a tertiary academic institution. A multivariable Cox regression analysis was carried out based on parameters proven to have an impact on postoperative renal function. Patients with incomplete data, <12 months follow up and preoperative chronic kidney disease stage III or greater were excluded. The study end-points were to identify independent risk factors for new-onset chronic kidney disease development, as well as to construct a predictive model for chronic kidney disease-free survival probability after partial nephrectomy. The median age was 52 years, median tumor size was 2.5 cm and mean warm ischemia time was 28 min. A total of 91 patients (13.1%) developed new-onset chronic kidney disease at a median follow up of 60 months. The chronic kidney disease-free survival rates at 1, 3, 5 and 10 year were 97.1%, 94.4%, 85.3% and 70.6%, respectively. On multivariable Cox regression analysis, age (1.041, P = 0.001), male sex (hazard ratio 1.653, P < 0.001), diabetes mellitus (hazard ratio 1.921, P = 0.046), tumor size (hazard ratio 1.331, P < 0.001) and preoperative estimated glomerular filtration rate (hazard ratio 0.937, P < 0.001) were independent predictors for new-onset chronic kidney disease. The C-index for chronic kidney disease-free survival was 0.853 (95% confidence interval 0.815-0.895). We developed a novel nomogram for predicting the 5-year chronic kidney disease-free survival probability after on-clamp partial nephrectomy. This model might have an important role in partial nephrectomy decision-making and follow-up plan after surgery. External validation of our nomogram in a larger cohort of patients should be considered. © 2018 The Japanese Urological Association.

Applied Prevalence Ratio estimation with different Regression models: An example from a cross-national study on substance use research.

PubMed

Espelt, Albert; Marí-Dell'Olmo, Marc; Penelo, Eva; Bosque-Prous, Marina

2016-06-14

To examine the differences between Prevalence Ratio (PR) and Odds Ratio (OR) in a cross-sectional study and to provide tools to calculate PR using two statistical packages widely used in substance use research (STATA and R). We used cross-sectional data from 41,263 participants of 16 European countries participating in the Survey on Health, Ageing and Retirement in Europe (SHARE). The dependent variable, hazardous drinking, was calculated using the Alcohol Use Disorders Identification Test - Consumption (AUDIT-C). The main independent variable was gender. Other variables used were: age, educational level and country of residence. PR of hazardous drinking in men with relation to women was estimated using Mantel-Haenszel method, log-binomial regression models and poisson regression models with robust variance. These estimations were compared to the OR calculated using logistic regression models. Prevalence of hazardous drinkers varied among countries. Generally, men have higher prevalence of hazardous drinking than women [PR=1.43 (1.38-1.47)]. Estimated PR was identical independently of the method and the statistical package used. However, OR overestimated PR, depending on the prevalence of hazardous drinking in the country. In cross-sectional studies, where comparisons between countries with differences in the prevalence of the disease or condition are made, it is advisable to use PR instead of OR.

How much do hazard mitigation plans cost? An analysis of federal grant data.

PubMed

Jackman, Andrea M; Beruvides, Mario G

2013-01-01

Under the Disaster Mitigation Act of 2000 and Federal Emergency Management Agency's subsequent Interim Final Rule, the requirement was placed on local governments to author and gain approval for a Hazard Mitigation Plan (HMP) for the areas under their jurisdiction. Low completion percentages for HMPs--less than one-third of eligible governments--were found by an analysis conducted 3 years after the final deadline for the aforementioned legislation took place. Follow-up studies showed little improvement at 5 and 8 years after the deadline. It was hypothesized that the cost of a HMP is a significant factor in determining whether or not a plan is completed. A study was conducted using Boolean Matrix Analysis methods to determine what, if any, characteristics of a certain community will most influence the cost of a HMP. The frequency of natural hazards experienced by the planning area, the number of jurisdictions participating in the HMEP, the population, and population density were found to significantly affect cost. These variables were used in a regression analysis to determine their predictive power for cost. It was found that along with two interaction terms, the variables explain approximately half the variation in HMP cost.

African American Race is an Independent Risk Factor in Survival from Initially Diagnosed Localized Breast Cancer

PubMed Central

Wieder, Robert; Shafiq, Basit; Adam, Nabil

2016-01-01

BACKGROUND: African American race negatively impacts survival from localized breast cancer but co-variable factors confound the impact. METHODS: Data sets were analyzed from the Surveillance, Epidemiology and End Results (SEER) directories from 1973 to 2011 consisting of patients with designated diagnosis of breast adenocarcinoma, race as White or Caucasian, Black or African American, Asian, American Indian or Alaskan Native, Native Hawaiian or Pacific Islander, age, stage I, II or III, grade 1, 2 or 3, estrogen receptor or progesterone receptor positive or negative, marital status as single, married, separated, divorced or widowed and laterality as right or left. The Cox Proportional Hazards Regression model was used to determine hazard ratios for survival. Chi square test was applied to determine the interdependence of variables found significant in the multivariable Cox Proportional Hazards Regression analysis. Cells with stratified data of patients with identical characteristics except African American or Caucasian race were compared. RESULTS: Age, stage, grade, ER and PR status and marital status significantly co-varied with race and with each other. Stratifications by single co-variables demonstrated worse hazard ratios for survival for African Americans. Stratification by three and four co-variables demonstrated worse hazard ratios for survival for African Americans in most subgroupings with sufficient numbers of values. Differences in some subgroupings containing poor prognostic co-variables did not reach significance, suggesting that race effects may be partly overcome by additional poor prognostic indicators. CONCLUSIONS: African American race is a poor prognostic indicator for survival from breast cancer independent of 6 associated co-variables with prognostic significance. PMID:27698895

Empirical and targeted therapy of candidemia with fluconazole versus echinocandins: a propensity score-derived analysis of a population-based, multicentre prospective cohort.

PubMed

López-Cortés, L E; Almirante, B; Cuenca-Estrella, M; Garnacho-Montero, J; Padilla, B; Puig-Asensio, M; Ruiz-Camps, I; Rodríguez-Baño, J

2016-08-01

We compared the clinical efficacy of fluconazole and echinocandins in the treatment of candidemia in real practice. The CANDIPOP study is a prospective, population-based cohort study on candidemia carried out between May 2010 and April 2011 in 29 Spanish hospitals. Using strict inclusion criteria, we separately compared the impact of empirical and targeted therapy with fluconazole or echinocandins on 30-day mortality. Cox regression, including a propensity score (PS) for receiving echinocandins, stratified analysis on the PS quartiles and PS-based matched analyses, were performed. The empirical and targeted therapy cohorts comprised 316 and 421 cases, respectively; 30-day mortality was 18.7% with fluconazole and 33.9% with echinocandins (p 0.02) in the empirical therapy group and 19.8% with fluconazole and 27.7% with echinocandins (p 0.06) in the targeted therapy group. Multivariate Cox regression analysis including PS showed that empirical therapy with fluconazole was associated with better prognosis (adjusted hazard ratio 0.38; 95% confidence interval 0.17-0.81; p 0.01); no differences were found within each PS quartile or in cases matched according to PS. Targeted therapy with fluconazole did not show a significant association with mortality in the Cox regression analysis (adjusted hazard ratio 0.77; 95% confidence interval 0.41-1.46; p 0.63), in the PS quartiles or in PS-matched cases. The results were similar among patients with severe sepsis and septic shock. Empirical or targeted treatment with fluconazole was not associated with increased 30-day mortality compared to echinocandins among adults with candidemia. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Considerations for analysis of time-to-event outcomes measured with error: Bias and correction with SIMEX.

PubMed

Oh, Eric J; Shepherd, Bryan E; Lumley, Thomas; Shaw, Pamela A

2018-04-15

For time-to-event outcomes, a rich literature exists on the bias introduced by covariate measurement error in regression models, such as the Cox model, and methods of analysis to address this bias. By comparison, less attention has been given to understanding the impact or addressing errors in the failure time outcome. For many diseases, the timing of an event of interest (such as progression-free survival or time to AIDS progression) can be difficult to assess or reliant on self-report and therefore prone to measurement error. For linear models, it is well known that random errors in the outcome variable do not bias regression estimates. With nonlinear models, however, even random error or misclassification can introduce bias into estimated parameters. We compare the performance of 2 common regression models, the Cox and Weibull models, in the setting of measurement error in the failure time outcome. We introduce an extension of the SIMEX method to correct for bias in hazard ratio estimates from the Cox model and discuss other analysis options to address measurement error in the response. A formula to estimate the bias induced into the hazard ratio by classical measurement error in the event time for a log-linear survival model is presented. Detailed numerical studies are presented to examine the performance of the proposed SIMEX method under varying levels and parametric forms of the error in the outcome. We further illustrate the method with observational data on HIV outcomes from the Vanderbilt Comprehensive Care Clinic. Copyright © 2017 John Wiley & Sons, Ltd.

Awareness of Occupational Hazards and Associated Factors among Automobile Repair Artisans in Kathmandu Metropolitan City, Nepal

PubMed Central

Marahatta, Sujan B.; Gautam, Sanju; Paudel, Grish; Yadav, Uday N.

2018-01-01

Background: An occupational hazard contributes to severe health problems among workers due to unhygienic conditions and lack of safety at the workplace. Economic growth and productivity can be well achieved by promoting health, safety, and improved quality workplace. Aims: To assess the knowledge of occupational hazards, use of Personal Protective Equipment (PPE) and the factors associated with awareness on occupational hazards among automobile repair artisans in Kathmandu, Nepal. Settings and Design: A quantitative descriptive cross-sectional study with 400 automobile repair artisans from Kathmandu metropolitan city was conducted between March and September, 2015. Materials and Methods: Simple random sampling was adopted for recruiting study participants. Pre-tested, validated semi-structured questionnaire was used in line with study objectives to collect the data. Statistical Analysis: Logistic regression analysis was employed to identify factors associated with the awareness of occupational hazard and PPE use. Results: Of total, 56% had awareness on occupational hazard and 44.3% of artisans were using the personal protective equipments. Being educated, having job duration ≥6 years and having pre-service training for work were significantly associated with the awareness of occupational hazards. Notably, we found that those who were aware of occupational hazard (OR = 3.01, 95% CI: 1.98–4.57) were three times more likely to use the safety measures when compared to those who were unaware. Conclusions: Awareness on occupational hazard and use of PPE is very low among automobile repair artisans in Kathmandu, Nepal. Therefore, interventions on awareness raising on areas, like provision of pre-service training, promotion of safety advocacy, and enforcement of appropriate regulations for work place. PMID:29743786

Replica analysis of overfitting in regression models for time-to-event data

NASA Astrophysics Data System (ADS)

Coolen, A. C. C.; Barrett, J. E.; Paga, P.; Perez-Vicente, C. J.

2017-09-01

Overfitting, which happens when the number of parameters in a model is too large compared to the number of data points available for determining these parameters, is a serious and growing problem in survival analysis. While modern medicine presents us with data of unprecedented dimensionality, these data cannot yet be used effectively for clinical outcome prediction. Standard error measures in maximum likelihood regression, such as p-values and z-scores, are blind to overfitting, and even for Cox’s proportional hazards model (the main tool of medical statisticians), one finds in literature only rules of thumb on the number of samples required to avoid overfitting. In this paper we present a mathematical theory of overfitting in regression models for time-to-event data, which aims to increase our quantitative understanding of the problem and provide practical tools with which to correct regression outcomes for the impact of overfitting. It is based on the replica method, a statistical mechanical technique for the analysis of heterogeneous many-variable systems that has been used successfully for several decades in physics, biology, and computer science, but not yet in medical statistics. We develop the theory initially for arbitrary regression models for time-to-event data, and verify its predictions in detail for the popular Cox model.

Clinical and multiple gene expression variables in survival analysis of breast cancer: Analysis with the hypertabastic survival model

PubMed Central

2012-01-01

Background We explore the benefits of applying a new proportional hazard model to analyze survival of breast cancer patients. As a parametric model, the hypertabastic survival model offers a closer fit to experimental data than Cox regression, and furthermore provides explicit survival and hazard functions which can be used as additional tools in the survival analysis. In addition, one of our main concerns is utilization of multiple gene expression variables. Our analysis treats the important issue of interaction of different gene signatures in the survival analysis. Methods The hypertabastic proportional hazards model was applied in survival analysis of breast cancer patients. This model was compared, using statistical measures of goodness of fit, with models based on the semi-parametric Cox proportional hazards model and the parametric log-logistic and Weibull models. The explicit functions for hazard and survival were then used to analyze the dynamic behavior of hazard and survival functions. Results The hypertabastic model provided the best fit among all the models considered. Use of multiple gene expression variables also provided a considerable improvement in the goodness of fit of the model, as compared to use of only one. By utilizing the explicit survival and hazard functions provided by the model, we were able to determine the magnitude of the maximum rate of increase in hazard, and the maximum rate of decrease in survival, as well as the times when these occurred. We explore the influence of each gene expression variable on these extrema. Furthermore, in the cases of continuous gene expression variables, represented by a measure of correlation, we were able to investigate the dynamics with respect to changes in gene expression. Conclusions We observed that use of three different gene signatures in the model provided a greater combined effect and allowed us to assess the relative importance of each in determination of outcome in this data set. These results point to the potential to combine gene signatures to a greater effect in cases where each gene signature represents some distinct aspect of the cancer biology. Furthermore we conclude that the hypertabastic survival models can be an effective survival analysis tool for breast cancer patients. PMID:23241496

Malnutrition risk predicts recovery of full oral intake among older adult stroke patients undergoing enteral nutrition: Secondary analysis of a multicentre survey (the APPLE study).

PubMed

Nishioka, Shinta; Okamoto, Takatsugu; Takayama, Masako; Urushihara, Maki; Watanabe, Misuzu; Kiriya, Yumiko; Shintani, Keiko; Nakagomi, Hiromi; Kageyama, Noriko

2017-08-01

Whether malnutrition risk correlates with recovery of swallowing function of convalescent stroke patients is unknown. This study was conducted to clarify whether malnutrition risks predict achievement of full oral intake in convalescent stroke patients undergoing enteral nutrition. We conducted a secondary analysis of 466 convalescent stroke patients, aged 65 years or over, who were undergoing enteral nutrition. Patients were extracted from the "Algorithm for Post-stroke Patients to improve oral intake Level; APPLE" study database compiled at the Kaifukuki (convalescent) rehabilitation wards. Malnutrition risk was determined by the Geriatric Nutritional Risk Index as follows: severe (<82), moderate (82 to <92), mild (92 to <98), and no malnutrition risks (≥98). Swallowing function was assessed by Fujishima's swallowing grade (FSG) on admission and discharge. The primary outcome was achievement of full oral intake, indicated by FSG ≥ 7. Binary logistic regression analysis was performed to identify predictive factors, including malnutrition risk, for achieving full oral intake. Estimated hazard risk was computed by Cox's hazard model. Of the 466 individuals, 264 were ultimately included in this study. Participants with severe malnutrition risk showed a significantly lower proportion of achievement of full oral intake than lower severity groups (P = 0.001). After adjusting for potential confounders, binary logistic regression analysis showed that patients with severe malnutrition risk were less likely to achieve full oral intake (adjusted odds ratio: 0.232, 95% confidence interval [95% CI]: 0.047-1.141). Cox's proportional hazard model revealed that severe malnutrition risk was an independent predictor of full oral intake (adjusted hazard ratio: 0.374, 95% CI: 0.166-0.842). Compared to patients who did not achieve full oral intake, patients who achieved full oral intake had significantly higher energy intake, but there was no difference in protein intake and weight change. Severe malnutrition risk independently predicts the achievement of full oral intake in convalescent stroke patients undergoing enteral nutrition. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Urbanization factors associated with childhood asthma and prematurity: a population-based analysis aged from 0 to 5 years in Taiwan by using Cox regression within a hospital cluster model.

PubMed

Lin, Sheng-Chieh; Lin, Hui-Wen

2015-04-01

Childhood asthma and premature birth are both common; however, no studies have reported urbanization association between asthma and prematurity and the duration of prematurity affect asthma development. We use Taiwan Longitudinal Health Insurance Database (LHID) to explore association between asthma and prematurity among children by using a population-based analysis. This is a retrospective cohort study with registration data derived from Taiwan LHID. We evaluated prematurely born infants and children aged <5 years (n = 532) and age-matched control patients (n = 60505) using Cox proportional hazard regression analysis within a hospital cluster model. Of the 61 037 examinees, 14 012 experienced asthma during the 5-year follow-up, including 161 (72.26 per 1000 person-years) infants and children born prematurely and 13 851 (40.27 per 1000 person-years) controls. The hazard ratio for asthma during 5-year follow-up period was 1.95 (95% confidence interval = 1.67-2.28) among children born prematurely. Boys born prematurely aged 0-2 years were associated with higher asthma rates compared with girls in non-premature and premature groups. Living in urban areas, those born prematurely were associated with higher rates of asthma compared with non-prematurity. Those born prematurely lived in northern region had higher asthma hazard ratio than other regions. Our analyses indicated that sex, age, urbanization level, and geographic region are significantly associated with prematurity and asthma. Based on cumulative asthma-free survival curve generated using the Kaplan-Meier method, infants born prematurely should be closely monitored to see if they would develop asthma until the age of 6 years.

[HIV/AIDS related mortality in southern Shanxi province and its risk factors].

PubMed

Ning, Shaoping; Xue, Zidong; Wei, Jun; Mu, Shengcai; Xu, Yajuan; Jia, Shaoxian; Qiu, Chao; Xu, Jianqing

2015-03-01

To explore factors influencing mortality rate of HIV/AIDS and to improve the effectiveness of antiretroviral therapy (ART). By means of retrospective cohort study and the AIDS control information system, HIV/AIDS case reports and antiviral treatment information of 4 cities in southern Shanxi province up to end of December 2012 were selected, to calculate the mortality rate and treatment coverage based on further data collected, along with analysis using the Cox proportional hazards survival regression. 4 040 cases confirmed of HIV/AIDS were included in this study. The average age was (36.0 ± 12.9) years, with 65.3% being male, 56.5% being married, 73.5% having junior high school education or lower, 58.4% being peasants, 54.3% with sexually transmitted infection (40.1% were heterosexual, 14.2% were homosexual), and 38.9% were infected via blood transmission (20.2% were former plasma donors, 16.2% blood transfusion or products recipients, 2.4% were injection drug users). Overall mortality decreased from 40.2 per 100 person/year in 2004 to 6.3 per 100 person/year in 2012, with treatment coverage concomitantly increasing from almost 14.8% to 63.4%. Cox proportional hazards survival regression was used on 4 040 qualified cases, demonstrating the top mortality risk factor was without antiretroviral therapy (RR = 14.9, 95% CI: 12.7-17.4). Cox proportional hazards survival regression was made on 1 938 cases of antiviral treatment, demonstrating that the mortality risk of underweight or obese before treatment was higher than those of normal and overweight cases (RR = 2.7, 95% CI: 1.6-4.5), and the mortality of those having a CD4(+) T-lymphocyte count ≤ 50 cells per µl before treatment was more than 50 cases (RR = 2.6, 95% CI: 1.5-4.5); Cox proportional hazards survival regression was made on 2 102 cases of untreated cases, demonstrating the mortality risk of those initially diagnosed as AIDS was higher than those initially diagnosed as HIV (RR = 3.4, 95% CI: 2.9-4.0). The ART could successfully make lower HIV/AIDS mortality rate, indicating effective ART can further decrease mortality.

Hazard Experience, Geophysical Vulnerability, and Flood Risk Perceptions in a Postdisaster City, the Case of New Orleans.

PubMed

Gotham, Kevin Fox; Campanella, Richard; Lauve-Moon, Katie; Powers, Bradford

2018-02-01

This article investigates the determinants of flood risk perceptions in New Orleans, Louisiana (United States), a deltaic coastal city highly vulnerable to seasonal nuisance flooding and hurricane-induced deluges and storm surges. Few studies have investigated the influence of hazard experience, geophysical vulnerability (hazard proximity), and risk perceptions in cities undergoing postdisaster recovery and rebuilding. We use ordinal logistic regression techniques to analyze experiential, geophysical, and sociodemographic variables derived from a survey of 384 residents in seven neighborhoods. We find that residents living in neighborhoods that flooded during Hurricane Katrina exhibit higher levels of perceived risk than those residents living in neighborhoods that did not flood. In addition, findings suggest that flood risk perception is positively associated with female gender, lower income, and direct flood experiences. In conclusion, we discuss the implications of these findings for theoretical and empirical research on environmental risk, flood risk communication strategies, and flood hazards planning. © 2017 Society for Risk Analysis.

Marital status and survival of patients with oral cavity squamous cell carcinoma: a population-based study.

PubMed

Shi, Xiao; Zhang, Ting-Ting; Hu, Wei-Ping; Ji, Qing-Hai

2017-04-25

The relationship between marital status and oral cavity squamous cell carcinoma (OCSCC) survival has not been explored. The objective of our study was to evaluate the impact of marital status on OCSCC survival and investigate the potential mechanisms. Married patients had better 5-year cancer-specific survival (CSS) (66.7% vs 54.9%) and 5-year overall survival (OS) (56.0% vs 41.1%). In multivariate Cox regression models, unmarried patients also showed higher mortality risk for both CSS (Hazard Ratio [HR]: 1.260, 95% confidence interval (CI): 1.187-1.339, P < 0.001) and OS (HR: 1.328, 95% CI: 1.266-1.392, P < 0.001). Multivariate logistic regression showed married patients were more likely to be diagnosed at earlier stage (P < 0.001) and receive surgery (P < 0.001). Married patients still demonstrated better prognosis in the 1:1 matched group analysis (CSS: 62.9% vs 60.8%, OS: 52.3% vs 46.5%). 11022 eligible OCSCC patients were identified from Surveillance, Epidemiology, and End Results (SEER) database, including 5902 married and 5120 unmarried individuals. Kaplan-Meier analysis, Log-rank test and Cox proportional hazards regression model were used to analyze survival and mortality risk. Influence of marital status on stage, age at diagnosis and selection of treatment was determined by binomial and multinomial logistic regression. Propensity score matching method was adopted to perform a 1:1 matched cohort. Marriage has an independently protective effect on OCSCC survival. Earlier diagnosis and more sufficient treatment are possible explanations. Besides, even after 1:1 matching, survival advantage of married group still exists, indicating that spousal support from other aspects may also play an important role.

Marital status and survival of patients with oral cavity squamous cell carcinoma: a population-based study

PubMed Central

Shi, Xiao; Zhang, Ting-ting; Hu, Wei-ping; Ji, Qing-hai

2017-01-01

Background The relationship between marital status and oral cavity squamous cell carcinoma (OCSCC) survival has not been explored. The objective of our study was to evaluate the impact of marital status on OCSCC survival and investigate the potential mechanisms. Results Married patients had better 5-year cancer-specific survival (CSS) (66.7% vs 54.9%) and 5-year overall survival (OS) (56.0% vs 41.1%). In multivariate Cox regression models, unmarried patients also showed higher mortality risk for both CSS (Hazard Ratio [HR]: 1.260, 95% confidence interval (CI): 1.187–1.339, P < 0.001) and OS (HR: 1.328, 95% CI: 1.266–1.392, P < 0.001). Multivariate logistic regression showed married patients were more likely to be diagnosed at earlier stage (P < 0.001) and receive surgery (P < 0.001). Married patients still demonstrated better prognosis in the 1:1 matched group analysis (CSS: 62.9% vs 60.8%, OS: 52.3% vs 46.5%). Materials and Methods 11022 eligible OCSCC patients were identified from Surveillance, Epidemiology, and End Results (SEER) database, including 5902 married and 5120 unmarried individuals. Kaplan-Meier analysis, Log-rank test and Cox proportional hazards regression model were used to analyze survival and mortality risk. Influence of marital status on stage, age at diagnosis and selection of treatment was determined by binomial and multinomial logistic regression. Propensity score matching method was adopted to perform a 1:1 matched cohort. Conclusions Marriage has an independently protective effect on OCSCC survival. Earlier diagnosis and more sufficient treatment are possible explanations. Besides, even after 1:1 matching, survival advantage of married group still exists, indicating that spousal support from other aspects may also play an important role. PMID:28415710

Molecular Classification Substitutes for the Prognostic Variables Stage, Age, and MYCN Status in Neuroblastoma Risk Assessment.

PubMed

Rosswog, Carolina; Schmidt, Rene; Oberthuer, André; Juraeva, Dilafruz; Brors, Benedikt; Engesser, Anne; Kahlert, Yvonne; Volland, Ruth; Bartenhagen, Christoph; Simon, Thorsten; Berthold, Frank; Hero, Barbara; Faldum, Andreas; Fischer, Matthias

2017-12-01

Current risk stratification systems for neuroblastoma patients consider clinical, histopathological, and genetic variables, and additional prognostic markers have been proposed in recent years. We here sought to select highly informative covariates in a multistep strategy based on consecutive Cox regression models, resulting in a risk score that integrates hazard ratios of prognostic variables. A cohort of 695 neuroblastoma patients was divided into a discovery set (n=75) for multigene predictor generation, a training set (n=411) for risk score development, and a validation set (n=209). Relevant prognostic variables were identified by stepwise multivariable L1-penalized least absolute shrinkage and selection operator (LASSO) Cox regression, followed by backward selection in multivariable Cox regression, and then integrated into a novel risk score. The variables stage, age, MYCN status, and two multigene predictors, NB-th24 and NB-th44, were selected as independent prognostic markers by LASSO Cox regression analysis. Following backward selection, only the multigene predictors were retained in the final model. Integration of these classifiers in a risk scoring system distinguished three patient subgroups that differed substantially in their outcome. The scoring system discriminated patients with diverging outcome in the validation cohort (5-year event-free survival, 84.9±3.4 vs 63.6±14.5 vs 31.0±5.4; P<.001), and its prognostic value was validated by multivariable analysis. We here propose a translational strategy for developing risk assessment systems based on hazard ratios of relevant prognostic variables. Our final neuroblastoma risk score comprised two multigene predictors only, supporting the notion that molecular properties of the tumor cells strongly impact clinical courses of neuroblastoma patients. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Freedom Solo Versus Trifecta Bioprotheses: Clinical and Hemodynamic Evaluation after Propensity Score Matching.

PubMed

J Cerqueira, Rui; Melo, Renata; Moreira, Soraia; A Saraiva, Francisca; Andrade, Marta; Salgueiro, Elson; Almeida, Jorge; J Amorim, Mário; Pinho, Paulo; Lourenço, André; F Leite-Moreira, Adelino

2017-01-01

To compare stentless Freedom Solo and stented Trifecta aortic bioprostheses regarding hemodynamic profile, left ventricular mass regression, early and late postoperative outcomes and survival. Longitudinal cohort study of consecutive patients undergoing aortic valve replacement (from 2009 to 2016) with either Freedom Solo or Trifecta at one centre. Local databases and national records were queried. Postoperative echocardiography (3-6 months) was obtained for hemodynamic profile (mean transprosthetic gradient and effective orifice area) and left ventricle mass determination. After propensity score matching (21 covariates), Kaplan-Meier analysis and cumulative incidence analysis were performed for survival and combined outcome of structural valve deterioration and endocarditis, respectively. Hemodynamics and left ventricle mass regression were assessed by a mixed- -effects model including propensity score as a covariate. From a total sample of 397 Freedom Solo and 525 Trifecta patients with a median follow-up time of 4.0 (2.2- 6.0) and 2.4 (1.4-3.7) years, respectively, a matched sample of 329 pairs was obtained. Well-balanced matched groups showed no difference in survival (hazard ratio=1.04, 95% confidence interval=0.69-1.56) or cumulative hazards of combined outcome (subhazard ratio=0.54, 95% confidence interval=0.21-1.39). Although Trifecta showed improved hemodynamic profile compared to Freedom Solo, no differences were found in left ventricle mass regression. Trifecta has a slightly improved hemodynamic profile compared to Freedom Solo but this does not translate into differences in the extent of mass regression, postoperative outcomes or survival, which were good and comparable for both bioprostheses. Long-term follow-up is needed for comparisons with older models of bioprostheses.

Support Vector Hazards Machine: A Counting Process Framework for Learning Risk Scores for Censored Outcomes.

PubMed

Wang, Yuanjia; Chen, Tianle; Zeng, Donglin

2016-01-01

Learning risk scores to predict dichotomous or continuous outcomes using machine learning approaches has been studied extensively. However, how to learn risk scores for time-to-event outcomes subject to right censoring has received little attention until recently. Existing approaches rely on inverse probability weighting or rank-based regression, which may be inefficient. In this paper, we develop a new support vector hazards machine (SVHM) approach to predict censored outcomes. Our method is based on predicting the counting process associated with the time-to-event outcomes among subjects at risk via a series of support vector machines. Introducing counting processes to represent time-to-event data leads to a connection between support vector machines in supervised learning and hazards regression in standard survival analysis. To account for different at risk populations at observed event times, a time-varying offset is used in estimating risk scores. The resulting optimization is a convex quadratic programming problem that can easily incorporate non-linearity using kernel trick. We demonstrate an interesting link from the profiled empirical risk function of SVHM to the Cox partial likelihood. We then formally show that SVHM is optimal in discriminating covariate-specific hazard function from population average hazard function, and establish the consistency and learning rate of the predicted risk using the estimated risk scores. Simulation studies show improved prediction accuracy of the event times using SVHM compared to existing machine learning methods and standard conventional approaches. Finally, we analyze two real world biomedical study data where we use clinical markers and neuroimaging biomarkers to predict age-at-onset of a disease, and demonstrate superiority of SVHM in distinguishing high risk versus low risk subjects.

Relationship between chemical structure and the occupational asthma hazard of low molecular weight organic compounds

PubMed Central

Jarvis, J; Seed, M; Elton, R; Sawyer, L; Agius, R

2005-01-01

Aims: To investigate quantitatively, relationships between chemical structure and reported occupational asthma hazard for low molecular weight (LMW) organic compounds; to develop and validate a model linking asthma hazard with chemical substructure; and to generate mechanistic hypotheses that might explain the relationships. Methods: A learning dataset used 78 LMW chemical asthmagens reported in the literature before 1995, and 301 control compounds with recognised occupational exposures and hazards other than respiratory sensitisation. The chemical structures of the asthmagens and control compounds were characterised by the presence of chemical substructure fragments. Odds ratios were calculated for these fragments to determine which were associated with a likelihood of being reported as an occupational asthmagen. Logistic regression modelling was used to identify the independent contribution of these substructures. A post-1995 set of 21 asthmagens and 77 controls were selected to externally validate the model. Results: Nitrogen or oxygen containing functional groups such as isocyanate, amine, acid anhydride, and carbonyl were associated with an occupational asthma hazard, particularly when the functional group was present twice or more in the same molecule. A logistic regression model using only statistically significant independent variables for occupational asthma hazard correctly assigned 90% of the model development set. The external validation showed a sensitivity of 86% and specificity of 99%. Conclusions: Although a wide variety of chemical structures are associated with occupational asthma, bifunctional reactivity is strongly associated with occupational asthma hazard across a range of chemical substructures. This suggests that chemical cross-linking is an important molecular mechanism leading to the development of occupational asthma. The logistic regression model is freely available on the internet and may offer a useful but inexpensive adjunct to the prediction of occupational asthma hazard. PMID:15778257

Predictors of pharmacological treatment outcomes with atomoxetine or methylphenidate in patients with attention-deficit/hyperactivity disorder from China, Egypt, Lebanon, Russian Federation, Taiwan, and United Arab Emirates.

PubMed

Treuer, T; Feng, Q; Desaiah, D; Altin, M; Wu, S; El-Shafei, A; Serebryakova, E; Gado, M; Faries, D

2014-09-01

The reduced availability of data from non-Western countries limits our ability to understand attention-deficit/hyperactivity disorder (ADHD) treatment outcomes, specifically, adherence and persistence of ADHD in children and adolescents. This analysis assessed predictors of treatment outcomes in a non-Western cohort of patients with ADHD treated with atomoxetine or methylphenidate. Data from a 12-month, prospective, observational study in outpatients aged 6-17 years treated with atomoxetine (N = 234) or methylphenidate (N = 221) were analysed post hoc to determine potential predictors of treatment outcomes. Participating countries included the Russian Federation, China, Taiwan, Egypt, United Arab Emirates and Lebanon. Factors associated with remission were analysed with stepwise multiple logistic regression and classification and regression trees (CART). Cox proportional hazards models with propensity score adjustment assessed differences in atomoxetine persistence among initial-dose cohorts. In patients treated with atomoxetine who had available dosing information (N = 134), Cox proportional hazards revealed lower (< 0.5 mg/kg) initial dose was significantly associated with shorter medication persistence (p < 0.01). multiple logistic regression analysis revealed greater rates of remission for atomoxetine-treated patients were associated with age (older), country (United Arab Emirates) and gender (female) (all p < 0.05). CART analysis confirmed older age and lack of specific phobias were associated with greater remission rates. For methylphenidate, greater baseline weight (highly correlated with the age factor found for atomoxetine) and prior atomoxetine use were associated with greater remission rates. These findings may help clinicians assess factors upon initiation of ADHD treatment to improve course prediction, proper dosing and treatment adherence and persistence. Observational study, therefore no registration. © 2014 John Wiley & Sons Ltd.

Cell cycle-related genes as modifiers of age of onset of colorectal cancer in Lynch syndrome: a large-scale study in non-Hispanic white patients.

PubMed

Chen, Jinyun; Pande, Mala; Huang, Yu-Jing; Wei, Chongjuan; Amos, Christopher I; Talseth-Palmer, Bente A; Meldrum, Cliff J; Chen, Wei V; Gorlov, Ivan P; Lynch, Patrick M; Scott, Rodney J; Frazier, Marsha L

2013-02-01

Heterogeneity in age of onset of colorectal cancer in individuals with mutations in DNA mismatch repair genes (Lynch syndrome) suggests the influence of other lifestyle and genetic modifiers. We hypothesized that genes regulating the cell cycle influence the observed heterogeneity as cell cycle-related genes respond to DNA damage by arresting the cell cycle to provide time for repair and induce transcription of genes that facilitate repair. We examined the association of 1456 single nucleotide polymorphisms (SNPs) in 128 cell cycle-related genes and 31 DNA repair-related genes in 485 non-Hispanic white participants with Lynch syndrome to determine whether there are SNPs associated with age of onset of colorectal cancer. Genotyping was performed on an Illumina GoldenGate platform, and data were analyzed using Kaplan-Meier survival analysis, Cox regression analysis and classification and regression tree (CART) methods. Ten SNPs were independently significant in a multivariable Cox proportional hazards regression model after correcting for multiple comparisons (P < 5 × 10(-4)). Furthermore, risk modeling using CART analysis defined combinations of genotypes for these SNPs with which subjects could be classified into low-risk, moderate-risk and high-risk groups that had median ages of colorectal cancer onset of 63, 50 and 42 years, respectively. The age-associated risk of colorectal cancer in the high-risk group was more than four times the risk in the low-risk group (hazard ratio = 4.67, 95% CI = 3.16-6.92). The additional genetic markers identified may help in refining risk groups for more tailored screening and follow-up of non-Hispanic white patients with Lynch syndrome.

Cell cycle–related genes as modifiers of age of onset of colorectal cancer in Lynch syndrome: a large-scale study in non-Hispanic white patients

PubMed Central

Chen, Jinyun; Pande, Mala

2013-01-01

Heterogeneity in age of onset of colorectal cancer in individuals with mutations in DNA mismatch repair genes (Lynch syndrome) suggests the influence of other lifestyle and genetic modifiers. We hypothesized that genes regulating the cell cycle influence the observed heterogeneity as cell cycle–related genes respond to DNA damage by arresting the cell cycle to provide time for repair and induce transcription of genes that facilitate repair. We examined the association of 1456 single nucleotide polymorphisms (SNPs) in 128 cell cycle–related genes and 31 DNA repair–related genes in 485 non-Hispanic white participants with Lynch syndrome to determine whether there are SNPs associated with age of onset of colorectal cancer. Genotyping was performed on an Illumina GoldenGate platform, and data were analyzed using Kaplan–Meier survival analysis, Cox regression analysis and classification and regression tree (CART) methods. Ten SNPs were independently significant in a multivariable Cox proportional hazards regression model after correcting for multiple comparisons (P < 5×10–4). Furthermore, risk modeling using CART analysis defined combinations of genotypes for these SNPs with which subjects could be classified into low-risk, moderate-risk and high-risk groups that had median ages of colorectal cancer onset of 63, 50 and 42 years, respectively. The age-associated risk of colorectal cancer in the high-risk group was more than four times the risk in the low-risk group (hazard ratio = 4.67, 95% CI = 3.16–6.92). The additional genetic markers identified may help in refining risk groups for more tailored screening and follow-up of non-Hispanic white patients with Lynch syndrome. PMID:23125224

Low thrombospondin 2 expression is predictive of low tumor regression after neoadjuvant chemoradiotherapy in rectal cancer.

PubMed

Lin, Cheng-Yi; Lin, Ching-Yih; Chang, I-Wei; Sheu, Ming-Jen; Li, Chien-Feng; Lee, Sung-Wei; Lin, Li-Ching; Lee, Ying-En; He, Hong-Lin

2015-01-01

Neoadjuvant concurrent chemoradiotherapy (CCRT) followed by surgery is the mainstay of treatment for locally advanced rectal cancer. Several heparin-binding associated proteins have been reported to play a critical role in cancer progression. However, the clinical relevancies of such proteins and their associations with CCRT response in rectal cancer have not yet to be fully elucidated. The analysis of a public transcriptome of rectal cancer indicated that thrombospondin 2 (THBS2) is a predictive factor for CCRT response. Immunohistochemical analyses were conducted to evaluate the expression of THBS2 in pretreatment biopsy specimens from rectal cancer patients without distant metastasis. Furthermore, the relationships between THBS2 expression and various clinicopathological factors or survival were analyzed. Low expression of THBS2 was significantly associated with advanced pretreatment tumor (P<0.001) and nodal status (P=0.004), post-treatment tumor (P<0.001) and nodal status (P<0.001), increased vascular invasion (P=0.003), increased perineural invasion (P=0.023) and inferior tumor regression grade (P=0.015). In univariate analysis, low THBS2 expression predicted worse outcomes for disease-free survival, local recurrence-free survival and metastasis-free survival (all P<0.001). In multivariate analysis, low expression of THBS2 still served as a negative prognostic factor for disease-free survival (Hazard ratio=3.057, P=0.002) and metastasis-free survival (Hazard ratio=3.362, P=0.012). Low THBS2 expression was correlated with advanced disease status and low tumor regression after preoperative CCRT and that it acted as an independent negative prognostic factor in rectal cancer. THBS2 may represent a predictive biomarker for CCRT response in rectal cancer.

Environmental hazards and stress: evidence from the Texas City Stress and Health Study.

PubMed

Peek, M K; Cutchin, M P; Freeman, D; Stowe, R P; Goodwin, J S

2009-10-01

Substantial research has suggested that exposure to environmental health hazards, such as polluting industrial activity, has deleterious effects on psychological and physiological well-being. However, one gap in the existing literature is comparative analysis of objective and subjective exposure's relative association with various measurable outcomes of exposure. These relationships were explored within a community sample of 2604 respondents living near a large petrochemical complex in Texas City, Texas, USA. Objective exposure was investigated using distance of residence from a cluster of petrochemical plants and subjective exposure using residents' concern about potential health effects from those plants. Regression models were then used to examine how each type of exposure predicts perceived stress, physiological markers of stress and perceived health. Results suggest that objective exposure was associated primarily with markers of physiological stress (interleukin-6 and viral reactivation), and subjective exposure (concern about petrochemical health risk) was associated with variables assessing perceived health. From the analysis, it can be inferred that, in the context of an environmental hazard of this type, subjective exposure may be at least as important a predictor of poor health outcomes as objective exposure.

Using multi-level data to estimate the effect of an 'alcogenic' environment on hazardous alcohol consumption in the former Soviet Union.

PubMed

Murphy, Adrianna; Roberts, Bayard; Ploubidis, George B; Stickley, Andrew; McKee, Martin

2014-05-01

The purpose of this study was to assess whether alcohol-related community characteristics act collectively to influence individual-level alcohol consumption in the former Soviet Union (fSU). Using multi-level data from nine countries in the fSU we conducted a factor analysis of seven alcohol-related community characteristics. The association between any latent factors underlying these characteristics and two measures of hazardous alcohol consumption was then analysed using a population average regression modelling approach. Our factor analysis produced one factor with an eigenvalue >1 (EV=1.28), which explained 94% of the variance. This factor was statistically significantly associated with increased odds of CAGE problem drinking (OR=1.40 (1.08-1.82)). The estimated association with EHD was not statistically significant (OR=1.10 (0.85-1.44)). Our findings suggest that a high number of beer, wine and spirit advertisements and high alcohol outlet density may work together to create an 'alcogenic' environment that encourages hazardous alcohol consumption in the fSU. Copyright © 2014 Elsevier Ltd. All rights reserved.

Complete hazard ranking to analyze right-censored data: An ALS survival study.

PubMed

Huang, Zhengnan; Zhang, Hongjiu; Boss, Jonathan; Goutman, Stephen A; Mukherjee, Bhramar; Dinov, Ivo D; Guan, Yuanfang

2017-12-01

Survival analysis represents an important outcome measure in clinical research and clinical trials; further, survival ranking may offer additional advantages in clinical trials. In this study, we developed GuanRank, a non-parametric ranking-based technique to transform patients' survival data into a linear space of hazard ranks. The transformation enables the utilization of machine learning base-learners including Gaussian process regression, Lasso, and random forest on survival data. The method was submitted to the DREAM Amyotrophic Lateral Sclerosis (ALS) Stratification Challenge. Ranked first place, the model gave more accurate ranking predictions on the PRO-ACT ALS dataset in comparison to Cox proportional hazard model. By utilizing right-censored data in its training process, the method demonstrated its state-of-the-art predictive power in ALS survival ranking. Its feature selection identified multiple important factors, some of which conflicts with previous studies.

Effect of motivational interviewing on rates of early childhood caries: a randomized trial.

PubMed

Harrison, Rosamund; Benton, Tonya; Everson-Stewart, Siobhan; Weinstein, Phil

2007-01-01

The purposes of this randomized controlled trial were to: (1) test motivational interviewing (MI) to prevent early childhood caries; and (2) use Poisson regression for data analysis. A total of 240 South Asian children 6 to 18 months old were enrolled and randomly assigned to either the MI or control condition. Children had a dental exam, and their mothers completed pretested instruments at baseline and 1 and 2 years postintervention. Other covariates that might explain outcomes over and above treatment differences were modeled using Poisson regression. Hazard ratios were produced. Analyses included all participants whenever possible. Poisson regression supported a protective effect of MI (hazard ratio [HR]=0.54 (95%CI=035-0.84)-that is, the M/ group had about a 46% lower rate of dmfs at 2 years than did control children. Similar treatment effect estimates were obtained from models that included, as alternative outcomes, ds, dms, and dmfs, including "white spot lesions." Exploratory analyses revealed that rates of dmfs were higher in children whose mothers had: (1) prechewed their food; (2) been raised in a rural environment; and (3) a higher family income (P<.05). A motivational interviewing-style intervention shows promise to promote preventive behaviors in mothers of young children at high risk for caries.

Sarcopenia is associated with incident albuminuria in patients with type 2 diabetes: A retrospective observational study.

PubMed

Bouchi, Ryotaro; Fukuda, Tatsuya; Takeuchi, Takato; Minami, Isao; Yoshimoto, Takanobu; Ogawa, Yoshihiro

2017-11-01

Sarcopenia, defined as age-related loss of skeletal muscle mass and function, increases the risk of albuminuria. However, it has still unknown whether sarcopenia could increase the risk for the progression of albuminuria. A total 238 patients with type 2 diabetes (mean age 64 ± 12 years; 39.2% women) were studied in the present retrospective observational study. The prevalence of sarcopenia was 17.6%. During the median follow-up period of 2.6 years, albuminuria was measured 5.8 ± 1.8 times, and progression of albuminuria was observed in 14.9% of patients with normoalbuminuria, as was 11.5% in those with microalbuminuria. Sarcopenia was significantly associated with both progression (hazard ratio 2.61, 95% confidence interval 1.08-6.31, P = 0.034) and regression (hazard ratio 0.23, 95% confidence interval 0.05-0.98, P = 0.048) of albuminuria by multivariate Cox regression analysis. The present data suggest that sarcopenia is an important determinant of both progression and regression of albuminuria in patients with type 2 diabetes. © 2017 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

Cox proportional hazards model of myopic regression for laser in situ keratomileusis flap creation with a femtosecond laser and with a mechanical microkeratome.

PubMed

Lin, Meng-Yin; Chang, David C K; Hsu, Wen-Ming; Wang, I-Jong

2012-06-01

To compare predictive factors for postoperative myopic regression between laser in situ keratomileusis (LASIK) with a femtosecond laser and LASIK with a mechanical microkeratome. Nobel Eye Clinic, Taipei, Taiwan. Retrospective comparative study. Refractive outcomes were recorded 1 day, 1 week, and 1, 3, 6, 9, and 12 months after LASIK. A Cox proportional hazards model was used to evaluate the impact of the 2 flap-creating methods and other covariates on postoperative myopic regression. The femtosecond group comprised 409 eyes and the mechanical microkeratome group, 377 eyes. For both methods, significant predictors for myopic regression after LASIK included preoperative manifest spherical equivalent (P=.0001) and central corneal thickness (P=.027). Laser in situ keratomileusis with a mechanical microkeratome had a higher probability of postoperative myopic regression than LASIK with a femtosecond laser (P=.0002). After adjusting for other covariates in the Cox proportional hazards model, the cumulative risk for myopic regression with a mechanical microkeratome was higher than with a femtosecond laser 12 months postoperatively (P=.0002). With the definition of myopic regression as a myopic shift of 0.50 diopter (D) or more and residual myopia of -0.50 D or less, the risk estimate based on the mean covariates in all eyes in the femtosecond group and mechanical microkeratome group at 12 months was 43.6% and 66.9%, respectively. Laser in situ keratomileusis with a mechanical microkeratome had a higher risk for myopic regression than LASIK with a femtosecond laser through 12 months postoperatively. Copyright © 2012. Published by Elsevier Inc.

Investigation of shift in decay hazard (Scheffer) index values over the period 1969-2008 in the conterminous United States

Treesearch

Patricia K. Lebow; Charles G. Carll

2010-01-01

A statistical analysis was performed that identified time trends in the Scheffer Index value for 167 locations in the conterminous United States over the period 1969-2008. Year-to-year variation in Index values was found to be larger than year-to-year variation in most other weather parameters. Despite the substantial yearly variation, regression equations, with time (...

Trail impacts in Sagarmatha (Mt. Everest) National Park, Nepal: a logistic regression analysis.

PubMed

Nepal, S K

2003-09-01

A trail study was conducted in the Sagarmatha (Mt. Everest) National Park, Nepal, during 1997-1998. Based on that study, this paper examines the spatial variability of trail conditions and analyzes factors that influence trail conditions. Logistic regression (multinomial logit model) is applied to examine the influence of use and environmental factors on trail conditions. The assessment of trail conditions is based on a four-class rating system: (class I, very little damaged; class II, moderately damaged, class III, heavily damaged; and class IV, severely damaged). Wald statistics and a model classification table have been used for data interpretation. Results indicate that altitude, trail gradient, hazard potential, and vegetation type are positively associated with trail condition. Trails are more degraded at higher altitude, on steep gradients, in areas with natural hazard potential, and within shrub/grassland zones. Strong correlations between high levels of trail degradation and higher frequencies of visitors and lodges were found. A detailed analysis of environmental and use factors could provide valuable information to park managers in their decisions about trail design, layout and maintenance, and efficient and effective visitor management strategies. Comparable studies on high alpine environments are needed to predict precisely the effects of topographic and climatic extremes. More refined approaches and experimental methods are necessary to control the effects of environmental factors.

Eradication of hepatitis C virus and non-liver-related non-acquired immune deficiency syndrome-related events in human immunodeficiency virus/hepatitis C virus coinfection.

PubMed

Berenguer, Juan; Rodríguez-Castellano, Elena; Carrero, Ana; Von Wichmann, Miguel A; Montero, Marta; Galindo, María J; Mallolas, Josep; Crespo, Manuel; Téllez, María J; Quereda, Carmen; Sanz, José; Barros, Carlos; Tural, Cristina; Santos, Ignacio; Pulido, Federico; Guardiola, Josep M; Rubio, Rafael; Ortega, Enrique; Montes, María L; Jusdado, Juan J; Gaspar, Gabriel; Esteban, Herminia; Bellón, José M; González-García, Juan

2017-08-01

We assessed non-liver-related non-acquired immunodeficiency syndrome (AIDS)-related (NLR-NAR) events and mortality in a cohort of human immunodeficiency virus (HIV)/hepatitis C virus (HCV)-coinfected patients treated with interferon (IFN) and ribavirin (RBV), between 2000 and 2008. The censoring date was May 31, 2014. Cox regression analysis was performed to assess the adjusted hazard rate (HR) of overall death in responders and nonresponders. Fine and Gray regression analysis was conducted to determine the adjusted subhazard rate (sHR) of NLR deaths and NLR-NAR events considering death as the competing risk. The NLR-NAR events analyzed included diabetes mellitus, chronic renal failure, cardiovascular events, NLR-NAR cancer, bone events, and non-AIDS-related infections. The variables for adjustment were age, sex, past AIDS, HIV transmission category, nadir CD4 + T-cell count, antiretroviral therapy, HIV RNA, liver fibrosis, HCV genotype, and exposure to specific anti-HIV drugs. Of the 1,625 patients included, 592 (36%) had a sustained viral response (SVR). After a median 5-year follow-up, SVR was found to be associated with a significant decrease in the hazard of diabetes mellitus (sHR, 0.57; 95% confidence interval [CI], 0.35-0.93; P = 0.024) and decline in the hazard of chronic renal failure close to the threshold of significance (sHR, 0.43; 95% CI, 0.17-1.09; P = 0.075). Our data suggest that eradication of HCV in coinfected patients is associated not only with a reduction in the frequency of death, HIV progression, and liver-related events, but also with a reduced hazard of diabetes mellitus and possibly of chronic renal failure. These findings argue for the prescription of HCV therapy in coinfected patients regardless of fibrosis stage. (Hepatology 2017;66:344-356). © 2017 The Authors. Hepatology published by Wiley Periodicals, Inc., on behalf of the American Association for the Study of Liver Diseases.

Social Hazards as Manifested Workplace Discrimination and Health (Vietnamese and Ukrainian Female and Male Migrants in Czechia)

PubMed Central

Drbohlav, Dušan; Dzúrová, Dagmar

2017-01-01

Social hazards as one of the dimensions of workplace discrimination are a potential social determinant of health inequalities. The aim of this study was to investigate relations between self-reported health and social hazard characteristics (defined as—discrimination as such, violence or threat of violence, time pressure or work overload and risk of accident) among Vietnamese and Ukrainian migrants (males and females) in Czechia by age, education level and marital status. This study is based on data from a survey of 669 immigrants in Czechia in 2013. Logistic regression analysis indicates that the given independent variables (given social hazards and socio-demographic characteristics), as predictors of a quality of self-reported health are more important for immigrant females than for males, irrespective of citizenship, albeit only for some of them and to differing extents. We found out that being exposed to the selected social hazards in the workplace leads to worsening self-rated health, especially for females. On the other hand, there was no statistically significant relationship found between poor self-rated health and discrimination as such. Reality calls for more research and, consequently, better policies and practices in the field of health inequalities. PMID:28994700

Social Hazards as Manifested Workplace Discrimination and Health (Vietnamese and Ukrainian Female and Male Migrants in Czechia).

PubMed

Drbohlav, Dušan; Dzúrová, Dagmar

2017-10-10

Social hazards as one of the dimensions of workplace discrimination are a potential social determinant of health inequalities. The aim of this study was to investigate relations between self-reported health and social hazard characteristics (defined as-discrimination as such, violence or threat of violence, time pressure or work overload and risk of accident) among Vietnamese and Ukrainian migrants (males and females) in Czechia by age, education level and marital status. This study is based on data from a survey of 669 immigrants in Czechia in 2013. Logistic regression analysis indicates that the given independent variables (given social hazards and socio-demographic characteristics), as predictors of a quality of self-reported health are more important for immigrant females than for males, irrespective of citizenship, albeit only for some of them and to differing extents. We found out that being exposed to the selected social hazards in the workplace leads to worsening self-rated health, especially for females. On the other hand, there was no statistically significant relationship found between poor self-rated health and discrimination as such. Reality calls for more research and, consequently, better policies and practices in the field of health inequalities.

Population-based cohort study investigating the correlation of diabetes mellitus with pleural empyema in adults in Taiwan.

PubMed

Lai, Shih-Wei; Lin, Cheng-Li; Liao, Kuan-Fu

2017-09-01

We assessed the association between diabetes mellitus and the risk of pleural empyema in Taiwan.A population-based retrospective cohort study was conducted using the database of the Taiwan National Health Insurance Program. There were 28,802 subjects aged 20 to 84 years who were newly diagnosed with diabetes mellitus from 2000 to 2010 as the diabetes group and 114,916 randomly selected subjects without diabetes mellitus as the non-diabetes group. The diabetes group and the non-diabetes group were matched by sex, age, comorbidities, and the year of index date. The incidence of pleural empyema at the end of 2011 was estimated. A multivariable Cox proportional hazards regression model was used to estimate the hazard ratio (HR) and 95% confidence interval (95% CI) for pleural empyema associated with diabetes mellitus.The overall incidence of pleural empyema was 1.65-fold higher in the diabetes group than that in the non-diabetes group (1.58 vs 0.96 per 10,000 person-years, 95% CI 1.57-1.72). After adjusting for confounders, a multivariable Cox proportional hazards regression model revealed that the adjusted HR of pleural empyema was 1.71 in subjects with diabetes mellitus (95% CI 1.16-2.51), compared with those without diabetes mellitus. In further analysis, even in the absence of any comorbidity, the adjusted HR was 1.99 for subjects with diabetes mellitus alone (95% CI 1.18-3.38).Diabetic patients confer a 1.71-fold increased hazard of developing pleural empyema. Even in the absence of any comorbidity, the risk remains existent.

Highly Prevalent Hyperuricaemia is Associated with Adverse Clinical Outcomes Among Ghanaian Stroke Patients: An Observational Prospective Study.

PubMed

Sarfo, F S; Akassi, J; Antwi, N K B; Obese, V; Adamu, S; Akpalu, A; Bedu-Addo, G

2015-09-01

Although a direct causal relationship between hyperuricaemia and stroke continues to be debated, strong associations between serum uric acid (SUA) and cerebrovascular disease exist. Very few studies have been conducted to evaluate the frequency and association between this potentially modifiable biomarker of vascular risk and stroke in sub-Saharan Africa. Therefore the aim of this study was to examine the association between hyperuricaemia and the traditional risk factors and the outcomes of stroke in Ghanaian patients. In this prospective observational study, 147 patients presenting with stroke at a tertiary referral centre in Ghana were consecutively recruited. Patients were screened for vascular risk factors and SUA concentrations measured after an overnight fast. Associations between hyperuricaemia and stroke outcomes were analysed using Kaplan-Meier and Cox proportional hazards regression analysis. The frequency of hyperuricaemia among Ghanaian stroke patients was 46.3%. Non-significant associations were observed between hyperuricaemia and the traditional risk factors of stroke. SUA concentration was positively correlated with stroke severity and associated with early mortality after an acute stroke with unadjusted hazards ratio of 2.3 (1.4 - 4.2, p=0.001). A potent and independent dose-response association between increasing SUA concentration and hazard of mortality was found on Cox proportional hazards regression, aHR (95% CI) of 1.65 (1.14-2.39), p=0.009 for each 100µmol/l increase in SUA. Hyperuricaemia is highly frequent and associated with adverse functional outcomes among Ghanaian stroke patients. Further studies are warranted to determine whether reducing SUA levels after a stroke would be beneficial within our setting.

Correlating regional natural hazards for global reinsurance risk assessment

NASA Astrophysics Data System (ADS)

Steptoe, Hamish; Maynard, Trevor; Economou, Theo; Fox, Helen; Wallace, Emily; Maisey, Paul

2016-04-01

Concurrent natural hazards represent an uncertainty in assessing exposure for the insurance industry. The recently implemented Solvency II Directive requires EU insurance companies to fully understand and justify their capital reserving and portfolio decisions. Lloyd's, the London insurance and reinsurance market, commissioned the Met Office to investigate the dependencies between different global extreme weather events (known to the industry as perils), and the mechanisms for these dependencies, with the aim of helping them assess their compound risk to the exposure of multiple simultaneous hazards. In this work, we base the analysis of hazard-to-hazard dependency on the interaction of different modes of global and regional climate variability. Lloyd's defined 16 key hazard regions, including Australian wildfires, flooding in China and EU windstorms, and we investigate the impact of 10 key climate modes on these areas. We develop a statistical model that facilitates rapid risk assessment whilst allowing for both temporal auto-correlation and, crucially, interdependencies between drivers. The simulator itself is built conditionally using autoregressive regression models for each driver conditional on the others. Whilst the baseline assumption within the (re)insurance industry is that different natural hazards are independent of each other, the assumption of independence of meteorological risks requires greater justification. Although our results suggest that most of the 120 hazard-hazard connections considered are likely to be independent of each other, 13 have significant dependence arising from one or more global modes of climate variability. This allows us to create a matrix of linkages describing the hazard dependency structure that Lloyd's can use to inform their understanding of risk.

Entry to lone parenthood: an analysis of marital dissolution in Great Britain.

PubMed

Ermisch, J F; Wright, R E

1994-01-01

"This paper examines some...socio-economic determinants of lone parenthood in Great Britain, in an attempt to understand further the reasons behind the rapid growth in lone parenthood. Since divorce and separation are the major 'causes' of lone parenthood, this paper focuses on the determinants of marital dissolution among women with dependent children. The empirical analysis is guided by hypotheses suggested by the 'economic theory of marriage'. Hazard regression equations are estimated with data collected in the 1980 Women and Employment Survey...." (SUMMARY IN FRE AND ITA) excerpt

Markov chains and semi-Markov models in time-to-event analysis.

PubMed

Abner, Erin L; Charnigo, Richard J; Kryscio, Richard J

2013-10-25

A variety of statistical methods are available to investigators for analysis of time-to-event data, often referred to as survival analysis. Kaplan-Meier estimation and Cox proportional hazards regression are commonly employed tools but are not appropriate for all studies, particularly in the presence of competing risks and when multiple or recurrent outcomes are of interest. Markov chain models can accommodate censored data, competing risks (informative censoring), multiple outcomes, recurrent outcomes, frailty, and non-constant survival probabilities. Markov chain models, though often overlooked by investigators in time-to-event analysis, have long been used in clinical studies and have widespread application in other fields.

Markov chains and semi-Markov models in time-to-event analysis

PubMed Central

Abner, Erin L.; Charnigo, Richard J.; Kryscio, Richard J.

2014-01-01

A variety of statistical methods are available to investigators for analysis of time-to-event data, often referred to as survival analysis. Kaplan-Meier estimation and Cox proportional hazards regression are commonly employed tools but are not appropriate for all studies, particularly in the presence of competing risks and when multiple or recurrent outcomes are of interest. Markov chain models can accommodate censored data, competing risks (informative censoring), multiple outcomes, recurrent outcomes, frailty, and non-constant survival probabilities. Markov chain models, though often overlooked by investigators in time-to-event analysis, have long been used in clinical studies and have widespread application in other fields. PMID:24818062

Work-related musculoskeletal injuries in Prosthetists and Orthotists in Australia.

PubMed

Anderson, S; Stuckey, R; Oakman, J

2018-06-12

This study aims to determine the prevalence of work-related musculoskeletal disorders in prosthetists/orthotists working in Australia. Secondary to this, the relationship between work-related hazards and work-related musculoskeletal disorders will be examined. In 2012 a self-report survey was conducted with the prosthetist/orthotist workforce in Australia (N=139, 56% response rate). Data on workplace physical and psychosocial hazards, job satisfaction, work life balance and musculoskeletal discomfort were collected. Predictors of work-related musculoskeletal disorders were assessed using logistic regression analysis. Prevalence of work-related musculoskeletal disorders was 80%. Gender (β= 1.31, p=0.03), total weekly hours (β=0.9, p<0.01), Physical (β=1.91, p<0.01) and Psychosocial (β=1.28, p<0.01) hazards were all associated with reporting of work-related musculoskeletal disorders. Females reported higher levels of work-related musculoskeletal disorder discomfort than males in all body areas. Work-related musculoskeletal disorders prevalence is high in prosthetists/orthotists. This suggests that focus on work place injury prevention is required. Targeted prevention requires systematic identification and then control of all relevant workplace hazards.

Gender differences in sex-related alcohol expectancies in young adults from a peri-urban area in Lima, Peru.

PubMed

Gálvez-Buccollini, Juan A; Paz-Soldán, Valerie A; Herrera, Phabiola M; DeLea, Suzanne; Gilman, Robert H

2009-06-01

To estimate the effect of sex-related alcohol expectancies (SRAE) on hazardous drinking prevalence and examine gender differences in reporting SRAE. Trained research assistants administered part of a questionnaire to 393 men and 400 women between 18 and 30 years old from a peri-urban shantytown in Lima, Peru. The remaining questions were self-administered. Two measuring instruments-one testing for hazardous drinking and one for SRAE-were used. Multivariate data analysis was performed using logistic regression. Based on odds ratios adjusted for socio-demographic variables (age, marital status, education, and employment status) (n = 793), men with one or two SRAE and men with three or more SRAE were 2.3 (95% confidence interval (CI) = 1.4-3.8; p = 0.001) and 3.9 (95% CI = 2.1-7.3; p < 0.001) times more likely than men with no SRAE, respectively, to be hazardous drinkers. Reporting of SRAE was significantly higher in men versus women. In a shantytown in Lima, SRAE is associated with hazardous drinking among men, but not among women, and reporting of SRAE differs by gender.

Immortal time bias in observational studies of time-to-event outcomes.

PubMed

Jones, Mark; Fowler, Robert

2016-12-01

The purpose of the study is to show, through simulation and example, the magnitude and direction of immortal time bias when an inappropriate analysis is used. We compare 4 methods of analysis for observational studies of time-to-event outcomes: logistic regression, standard Cox model, landmark analysis, and time-dependent Cox model using an example data set of patients critically ill with influenza and a simulation study. For the example data set, logistic regression, standard Cox model, and landmark analysis all showed some evidence that treatment with oseltamivir provides protection from mortality in patients critically ill with influenza. However, when the time-dependent nature of treatment exposure is taken account of using a time-dependent Cox model, there is no longer evidence of a protective effect of treatment. The simulation study showed that, under various scenarios, the time-dependent Cox model consistently provides unbiased treatment effect estimates, whereas standard Cox model leads to bias in favor of treatment. Logistic regression and landmark analysis may also lead to bias. To minimize the risk of immortal time bias in observational studies of survival outcomes, we strongly suggest time-dependent exposures be included as time-dependent variables in hazard-based analyses. Copyright © 2016 Elsevier Inc. All rights reserved.

Multi -risk assessment at a national level in Georgia

NASA Astrophysics Data System (ADS)

Tsereteli, Nino; Varazanashvili, Otar; Amiranashvili, Avtandil; Tsereteli, Emili; Elizbarashvili, Elizbar; Saluqvadze, Manana; Dolodze, Jemal

2013-04-01

Work presented here was initiated by national GNSF project " Reducing natural disasters multiple risk: a positive factor for Georgia development " and two international projects: NATO SFP 983038 "Seismic hazard and Rusk assessment for Southern Caucasus-eastern Turkey Energy Corridors" and EMME " Earthquake Model for Middle east Region". Methodology for estimation of "general" vulnerability, hazards and multiple risk to natural hazards (namely, earthquakes, landslides, snow avalanches, flash floods, mudflows, drought, hurricanes, frost, hail) where developed for Georgia. The electronic detailed databases of natural disasters were created. These databases contain the parameters of hazardous phenomena that caused natural disasters. The magnitude and intensity scale of the mentioned disasters are reviewed and the new magnitude and intensity scales are suggested for disasters for which the corresponding formalization is not yet performed. The associated economic losses were evaluated and presented in monetary terms for these hazards. Based on the hazard inventory, an approach was developed that allowed for the calculation of an overall vulnerability value for each individual hazard type, using the Gross Domestic Product per unit area (applied to population) as the indicator for elements at risk exposed. The correlation between estimated economic losses, physical exposure and the magnitude for each of the six types of hazards has been investigated in detail by using multiple linear regression analysis. Economic losses for all past events and historical vulnerability were estimated. Finally, the spatial distribution of general vulnerability was assessed, and the expected maximum economic loss was calculated as well as a multi-risk map was set-up.

Regression analysis of current-status data: an application to breast-feeding.

PubMed

Grummer-strawn, L M

1993-09-01

"Although techniques for calculating mean survival time from current-status data are well known, their use in multiple regression models is somewhat troublesome. Using data on current breast-feeding behavior, this article considers a number of techniques that have been suggested in the literature, including parametric, nonparametric, and semiparametric models as well as the application of standard schedules. Models are tested in both proportional-odds and proportional-hazards frameworks....I fit [the] models to current status data on breast-feeding from the Demographic and Health Survey (DHS) in six countries: two African (Mali and Ondo State, Nigeria), two Asian (Indonesia and Sri Lanka), and two Latin American (Colombia and Peru)." excerpt

A proportional hazards regression model for the subdistribution with right-censored and left-truncated competing risks data

PubMed Central

Zhang, Xu; Zhang, Mei-Jie; Fine, Jason

2012-01-01

With competing risks failure time data, one often needs to assess the covariate effects on the cumulative incidence probabilities. Fine and Gray proposed a proportional hazards regression model to directly model the subdistribution of a competing risk. They developed the estimating procedure for right-censored competing risks data, based on the inverse probability of censoring weighting. Right-censored and left-truncated competing risks data sometimes occur in biomedical researches. In this paper, we study the proportional hazards regression model for the subdistribution of a competing risk with right-censored and left-truncated data. We adopt a new weighting technique to estimate the parameters in this model. We have derived the large sample properties of the proposed estimators. To illustrate the application of the new method, we analyze the failure time data for children with acute leukemia. In this example, the failure times for children who had bone marrow transplants were left truncated. PMID:21557288

The influence of meteorology on the spread of influenza: survival analysis of an equine influenza (A/H3N8) outbreak.

PubMed

Firestone, Simon M; Cogger, Naomi; Ward, Michael P; Toribio, Jenny-Ann L M L; Moloney, Barbara J; Dhand, Navneet K

2012-01-01

The influences of relative humidity and ambient temperature on the transmission of influenza A viruses have recently been established under controlled laboratory conditions. The interplay of meteorological factors during an actual influenza epidemic is less clear, and research into the contribution of wind to epidemic spread is scarce. By applying geostatistics and survival analysis to data from a large outbreak of equine influenza (A/H3N8), we quantified the association between hazard of infection and air temperature, relative humidity, rainfall, and wind velocity, whilst controlling for premises-level covariates. The pattern of disease spread in space and time was described using extraction mapping and instantaneous hazard curves. Meteorological conditions at each premises location were estimated by kriging daily meteorological data and analysed as time-lagged time-varying predictors using generalised Cox regression. Meteorological covariates time-lagged by three days were strongly associated with hazard of influenza infection, corresponding closely with the incubation period of equine influenza. Hazard of equine influenza infection was higher when relative humidity was <60% and lowest on days when daily maximum air temperature was 20-25°C. Wind speeds >30 km hour(-1) from the direction of nearby infected premises were associated with increased hazard of infection. Through combining detailed influenza outbreak and meteorological data, we provide empirical evidence for the underlying environmental mechanisms that influenced the local spread of an outbreak of influenza A. Our analysis supports, and extends, the findings of studies into influenza A transmission conducted under laboratory conditions. The relationships described are of direct importance for managing disease risk during influenza outbreaks in horses, and more generally, advance our understanding of the transmission of influenza A viruses under field conditions.

The Influence of Meteorology on the Spread of Influenza: Survival Analysis of an Equine Influenza (A/H3N8) Outbreak

PubMed Central

Firestone, Simon M.; Cogger, Naomi; Ward, Michael P.; Toribio, Jenny-Ann L. M. L.; Moloney, Barbara J.; Dhand, Navneet K.

2012-01-01

The influences of relative humidity and ambient temperature on the transmission of influenza A viruses have recently been established under controlled laboratory conditions. The interplay of meteorological factors during an actual influenza epidemic is less clear, and research into the contribution of wind to epidemic spread is scarce. By applying geostatistics and survival analysis to data from a large outbreak of equine influenza (A/H3N8), we quantified the association between hazard of infection and air temperature, relative humidity, rainfall, and wind velocity, whilst controlling for premises-level covariates. The pattern of disease spread in space and time was described using extraction mapping and instantaneous hazard curves. Meteorological conditions at each premises location were estimated by kriging daily meteorological data and analysed as time-lagged time-varying predictors using generalised Cox regression. Meteorological covariates time-lagged by three days were strongly associated with hazard of influenza infection, corresponding closely with the incubation period of equine influenza. Hazard of equine influenza infection was higher when relative humidity was <60% and lowest on days when daily maximum air temperature was 20–25°C. Wind speeds >30 km hour−1 from the direction of nearby infected premises were associated with increased hazard of infection. Through combining detailed influenza outbreak and meteorological data, we provide empirical evidence for the underlying environmental mechanisms that influenced the local spread of an outbreak of influenza A. Our analysis supports, and extends, the findings of studies into influenza A transmission conducted under laboratory conditions. The relationships described are of direct importance for managing disease risk during influenza outbreaks in horses, and more generally, advance our understanding of the transmission of influenza A viruses under field conditions. PMID:22536366

Myocardial Injury in Patients With Sepsis and Its Association With Long-Term Outcome.

PubMed

Frencken, Jos F; Donker, Dirk W; Spitoni, Cristian; Koster-Brouwer, Marlies E; Soliman, Ivo W; Ong, David S Y; Horn, Janneke; van der Poll, Tom; van Klei, Wilton A; Bonten, Marc J M; Cremer, Olaf L

2018-02-01

Sepsis is frequently complicated by the release of cardiac troponin, but the clinical significance of this myocardial injury remains unclear. We studied the associations between troponin release during sepsis and 1-year outcomes. We enrolled consecutive patients with sepsis in 2 Dutch intensive care units between 2011 and 2013. Subjects with a clinically apparent cause of troponin release were excluded. High-sensitivity cardiac troponin I (hs-cTnI) concentration in plasma was measured daily during the first 4 intensive care unit days, and multivariable Cox regression analysis was used to model its association with 1-year mortality while adjusting for confounding. In addition, we studied cardiovascular morbidity occurring during the first year after hospital discharge. Among 1258 patients presenting with sepsis, 1124 (89%) were eligible for study inclusion. Hs-cTnI concentrations were elevated in 673 (60%) subjects on day 1, and 755 (67%) ever had elevated levels in the first 4 days. Cox regression analysis revealed that high hs-cTnI concentrations were associated with increased death rates during the first 14 days (adjusted hazard ratio, 1.72; 95% confidence interval, 1.14-2.59 and hazard ratio, 1.70; 95% confidence interval, 1.10-2.62 for hs-cTnI concentrations of 100-500 and >500 ng/L, respectively) but not thereafter. Furthermore, elevated hs-cTnI levels were associated with the development of cardiovascular disease among 200 hospital survivors who were analyzed for this end point (adjusted subdistribution hazard ratio, 1.25; 95% confidence interval, 1.04-1.50). Myocardial injury occurs in the majority of patients with sepsis and is independently associated with early-but not late-mortality, as well as postdischarge cardiovascular morbidity. © 2018 American Heart Association, Inc.

Using In Vitro High-Throughput Screening Data for Predicting Benzo[k]Fluoranthene Human Health Hazards.

PubMed

Burgoon, Lyle D; Druwe, Ingrid L; Painter, Kyle; Yost, Erin E

2017-02-01

Today there are more than 80,000 chemicals in commerce and the environment. The potential human health risks are unknown for the vast majority of these chemicals as they lack human health risk assessments, toxicity reference values, and risk screening values. We aim to use computational toxicology and quantitative high-throughput screening (qHTS) technologies to fill these data gaps, and begin to prioritize these chemicals for additional assessment. In this pilot, we demonstrate how we were able to identify that benzo[k]fluoranthene may induce DNA damage and steatosis using qHTS data and two separate adverse outcome pathways (AOPs). We also demonstrate how bootstrap natural spline-based meta-regression can be used to integrate data across multiple assay replicates to generate a concentration-response curve. We used this analysis to calculate an in vitro point of departure of 0.751 μM and risk-specific in vitro concentrations of 0.29 μM and 0.28 μM for 1:1,000 and 1:10,000 risk, respectively, for DNA damage. Based on the available evidence, and considering that only a single HSD17B4 assay is available, we have low overall confidence in the steatosis hazard identification. This case study suggests that coupling qHTS assays with AOPs and ontologies will facilitate hazard identification. Combining this with quantitative evidence integration methods, such as bootstrap meta-regression, may allow risk assessors to identify points of departure and risk-specific internal/in vitro concentrations. These results are sufficient to prioritize the chemicals; however, in the longer term we will need to estimate external doses for risk screening purposes, such as through margin of exposure methods. © 2016 Society for Risk Analysis.

Racial Disparity in Renal Transplantation: Alemtuzumab the Great Equalizer?

PubMed

Smith, Alison A; John, Mira M; Dortonne, Isabelle S; Paramesh, Anil S; Killackey, Mary; Jaffe, Bernard M; Buell, Joseph F

2015-10-01

Racial disparity as a barrier to successful outcomes in renal transplants for African Americans has been well described. Numerous unsuccessful attempts have been made to identify specific immunologic and socioeconomic factors. The objective of our study was to determine whether alemtuzumab (AL) induction abolishes this discrepancy and improves allograft survival in African American recipients. A retrospective chart review of consecutive adult renal transplants was conducted between 2006 and 2014. Kaplan-Meier analysis and hazard ratios were calculated for the African Americans (AA) and white groups. Multiple linear regressions were performed to assess independent variables (race, retransplant, sex, donor type, induction agent) on allograft survival. A significant difference in allograft survival was identified between whites (n = 272) and AA (n = 445), with AA experiencing more graft losses (18.2% vs 12.1%, P = 0.0351). Induction with AL improved outcomes in all transplant recipients. Multiple linear regression identified that the strongest predictor of allograft failure was induction without AL (P < 0.0001). The data for a subset analysis matched for follow-up length demonstrated that whites compared with AA (n = 157, 67 whites and 90 AA) had lower rates of allograft failure in the absence of AL induction (14.9% vs 44.4%, P = 0.0156, hazard ratio = 2.077). In contrast, AL induction (n = 275, 105 whites and 170 AA) eliminated the racial disparity in allograft failure (5.7% vs 9.4%, P = 0.8248, hazard ratio = 1.504). This is the first study to describe the effects of AL induction therapy on AA renal transplant recipients beyond the first posttransplant year. Our early results suggest that AL induction therapy abolishes the disparity in renal allograft failure.

Clinical Characteristics and Prognosis of End-stage Hypertrophic Cardiomyopathy.

PubMed

Xiao, Yan; Yang, Kun-Qi; Yang, Yan-Kun; Liu, Ya-Xin; Tian, Tao; Song, Lei; Jiang, Xiong-Jing; Zhou, Xian-Liang

2015-06-05

End-stage hypertrophic cardiomyopathy (HCM) is complicated by substantial adverse events. However, few studies have focused on electrocardiographic features and their prognostic values in HCM. This study aimed to evaluate the clinical manifestations and prognostic value of electrocardiography in patients with end-stage HCM. End-stage HCM patients were enrolled from a total of 1844 consecutive HCM patients from April 2002 to November 2013 at Fuwai Hospital. Clinical data, including medical history, electrocardiography, and echocardiography, were analyzed. Cox hazards regression analysis was used to assess the risk factors for cardiovascular mortality. End-stage HCM was identified in 99 (5.4%) patients, averaged at 52 ± 16 years old at entry. Atrial fibrillation was observed in 53 patients and mural thrombus in 19 patients. During 3.9 ± 3.0 years of follow-up, embolic stroke, refractory heart failure, and death or transplantation were observed in 20, 39, and 51 patients, respectively. The incidence of annual mortality was 13.2%. Multivariate Cox hazards regression analysis identified New York Heart Association Class (NYHA) III/IV at entry (hazard ratio [HR]: 1.99; 95% confidence interval [CI]: 1.05-3.80; P = 0.036), left bundle branch block (LBBB) (HR: 2.80; 95% CI: 1.47-5.31; P = 0.002), and an abnormal Q wave (HR: 2.21; 95% CI: 1.16-4.23; P = 0.016) as independent predictors of cardiovascular death, in accordance with all-cause death and heart failure-related death. LBBB and an abnormal Q wave are risk factors of cardiovascular mortality in end-stage HCM and provide new evidence for early intervention. Susceptibility of end-stage HCM patients to mural thrombus and embolic events warrants further attention.

Correction of Selection Bias in Survey Data: Is the Statistical Cure Worse Than the Bias?

PubMed

Hanley, James A

2017-04-01

In previous articles in the American Journal of Epidemiology (Am J Epidemiol. 2013;177(5):431-442) and American Journal of Public Health (Am J Public Health. 2013;103(10):1895-1901), Masters et al. reported age-specific hazard ratios for the contrasts in mortality rates between obesity categories. They corrected the observed hazard ratios for selection bias caused by what they postulated was the nonrepresentativeness of the participants in the National Health Interview Study that increased with age, obesity, and ill health. However, it is possible that their regression approach to remove the alleged bias has not produced, and in general cannot produce, sensible hazard ratio estimates. First, we must consider how many nonparticipants there might have been in each category of obesity and of age at entry and how much higher the mortality rates would have to be in nonparticipants than in participants in these same categories. What plausible set of numerical values would convert the ("biased") decreasing-with-age hazard ratios seen in the data into the ("unbiased") increasing-with-age ratios that they computed? Can these values be encapsulated in (and can sensible values be recovered from) one additional internal variable in a regression model? Second, one must examine the age pattern of the hazard ratios that have been adjusted for selection. Without the correction, the hazard ratios are attenuated with increasing age. With it, the hazard ratios at older ages are considerably higher, but those at younger ages are well below one. Third, one must test whether the regression approach suggested by Masters et al. would correct the nonrepresentativeness that increased with age and ill health that I introduced into real and hypothetical data sets. I found that the approach did not recover the hazard ratio patterns present in the unselected data sets: the corrections overshot the target at older ages and undershot it at lower ages.

Correlation and simple linear regression.

PubMed

Eberly, Lynn E

2007-01-01

This chapter highlights important steps in using correlation and simple linear regression to address scientific questions about the association of two continuous variables with each other. These steps include estimation and inference, assessing model fit, the connection between regression and ANOVA, and study design. Examples in microbiology are used throughout. This chapter provides a framework that is helpful in understanding more complex statistical techniques, such as multiple linear regression, linear mixed effects models, logistic regression, and proportional hazards regression.

Environmental hazards and stress: evidence from the Texas City Stress and Health Study

PubMed Central

Peek, MK; Cutchin, MP; Freeman, D; Stowe, RP; Goodwin, JS

2013-01-01

Background Substantial research has suggested that exposure to environmental health hazards, such as polluting industrial activity, has deleterious effects on psychological and physiological well-being. However, one gap in the existing literature is comparative analysis of objective and subjective exposure's relative association with various measurable outcomes of exposure. Methods These relationships were explored within a community sample of 2604 respondents living near a large petrochemical complex in Texas City, Texas, USA. Objective exposure was investigated using distance of residence from a cluster of petrochemical plants and subjective exposure using residents' concern about potential health effects from those plants. Regression models were then used to examine how each type of exposure predicts perceived stress, physiological markers of stress and perceived health. Results Results suggest that objective exposure was associated primarily with markers of physiological stress (interleukin-6 and viral reactivation), and subjective exposure (concern about petrochemical health risk) was associated with variables assessing perceived health. Conclusions From the analysis, it can be inferred that, in the context of an environmental hazard of this type, subjective exposure may be at least as important a predictor of poor health outcomes as objective exposure. PMID:19282316

Impact of scalp location on survival in head and neck melanoma: A retrospective cohort study.

PubMed

Xie, Charles; Pan, Yan; McLean, Catriona; Mar, Victoria; Wolfe, Rory; Kelly, John

2017-03-01

Scalp melanomas have more aggressive clinicopathological features than other melanomas and mortality rates more than twice that of melanoma located elsewhere. We sought to describe the survival of patients with scalp melanoma versus other cutaneous head and neck melanoma (CHNM), and explore a possible independent negative impact of scalp location on CHNM survival. A retrospective cohort study was performed of all invasive primary CHNM cases seen at a tertiary referral center over a 20-year period. Melanoma-specific survival (MSS) was compared between scalp melanoma and other invasive CHNM. Multivariable Cox proportional hazards regression was performed to determine associations with survival. On univariate analysis, patients with scalp melanoma had worse MSS than other CHNM (hazard ratio 2.22, 95% confidence interval 1.59-3.11). Scalp location was not associated with MSS in CHNM on multivariable analysis (hazard ratio 1.11, 95% confidence interval 0.77-1.61) for all tumors together, but remained independently associated with MSS for the 0.76- to 1.50-mm thickness stratum (hazard ratio 5.51, 95% confidence interval 1.55-19.59). Disease recurrence was not assessed because of unavailable data. The poorer survival of scalp melanoma is largely explained by greater Breslow thickness and a higher proportion of male patients. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Predictive modeling of hazardous waste landfill total above-ground biomass using passive optical and LIDAR remotely sensed data

NASA Astrophysics Data System (ADS)

Hadley, Brian Christopher

This dissertation assessed remotely sensed data and geospatial modeling technique(s) to map the spatial distribution of total above-ground biomass present on the surface of the Savannah River National Laboratory's (SRNL) Mixed Waste Management Facility (MWMF) hazardous waste landfill. Ordinary least squares (OLS) regression, regression kriging, and tree-structured regression were employed to model the empirical relationship between in-situ measured Bahia (Paspalum notatum Flugge) and Centipede [Eremochloa ophiuroides (Munro) Hack.] grass biomass against an assortment of explanatory variables extracted from fine spatial resolution passive optical and LIDAR remotely sensed data. Explanatory variables included: (1) discrete channels of visible, near-infrared (NIR), and short-wave infrared (SWIR) reflectance, (2) spectral vegetation indices (SVI), (3) spectral mixture analysis (SMA) modeled fractions, (4) narrow-band derivative-based vegetation indices, and (5) LIDAR derived topographic variables (i.e. elevation, slope, and aspect). Results showed that a linear combination of the first- (1DZ_DGVI), second- (2DZ_DGVI), and third-derivative of green vegetation indices (3DZ_DGVI) calculated from hyperspectral data recorded over the 400--960 nm wavelengths of the electromagnetic spectrum explained the largest percentage of statistical variation (R2 = 0.5184) in the total above-ground biomass measurements. In general, the topographic variables did not correlate well with the MWMF biomass data, accounting for less than five percent of the statistical variation. It was concluded that tree-structured regression represented the optimum geospatial modeling technique due to a combination of model performance and efficiency/flexibility factors.

Prognostic impact of metastatic pattern in stage IV breast cancer at initial diagnosis.

PubMed

Leone, Bernardo Amadeo; Vallejo, Carlos Teodoro; Romero, Alberto Omar; Machiavelli, Mario Raúl; Pérez, Juan Eduardo; Leone, Julieta; Leone, José Pablo

2017-02-01

To analyze the prognostic influence of metastatic pattern (MP) compared with other biologic and clinical factors in stage IV breast cancer at initial diagnosis (BCID) and evaluate factors associated with specific sites of metastases (SSM). We evaluated women with stage IV BCID with known metastatic sites, reported to the Surveillance, Epidemiology and End Results program from 2010 to 2013. MP was categorized as bone-only, visceral, bone and visceral (BV), and other. Univariate and multivariate analyses determined the effects of each variable on overall survival (OS). Logistic regression examined factors associated with SSM. We included 9143 patients. Bone represented 37.5% of patients, visceral 21.9%, BV 28.8%, and other 11.9%. Median OS by MP was as follows: bone 38 months, visceral 21 months, BV 19 months, and other 33 months (P < 0.0001). Univariate analysis showed that higher number of metastatic sites had worse prognosis. In multivariate analysis, older age (hazard ratio 1.9), black race (hazard ratio 1.17), grade 3/4 tumors (hazard ratio 1.6), triple-negative (hazard ratio 2.24), BV MP (hazard ratio 2.07), and unmarried patients (hazard ratio 1.25) had significantly shorter OS. As compared with HR+/HER2- tumors, triple-negative and HR-/HER2+ had higher odds of brain, liver, lung, and other metastases. HR+/HER2+ had higher odds of liver metastases. All three subtypes had lower odds of bone metastases. There were substantial differences in OS according to MP. Tumor subtypes have a clear influence among other factors on SSM. We identified several prognostic factors that could guide therapy selection in treatment naïve patients.

Does age matter in predicting musculoskeletal disorder risk? An analysis of workplace predictors over 4 years.

PubMed

Oakman, Jodi; Neupane, Subas; Nygård, Clas-Håkan

2016-10-01

Musculoskeletal disorders (MSDs) are a major workplace issue. With increasing pressure to extend working lives, predictors of MSD risk across all age groups require accurate identification to inform risk reduction strategies. In 2005 and 2009, a survey was conducted in a Finnish food processing company (N = 734). Data on workplace physical and psychosocial hazards, work ability, job satisfaction and lifestyle-related variables were collected, and MSD risk was measured through assessment of work-related strain in four body areas. Predictors of MSD risk across three age groups (20-35, 36-49, 50+) were assessed with linear regression analysis. Physical hazards and MSD risk were related differently for each age group. The relationship between psychosocial hazards and MSD risk was less clear. For younger workers, physical hazards were not associated with MSD risk. In contrast, for those aged 36-49, repetitive movements (B = 1.76, p < 0.001) and awkward postures (B = 1.30, p = 0.02) were associated with increased MSD risk. For older workers, environmental hazards were positively associated with MSD risk (B = 0.37, p = 0.04). Predictors of MSD risk changed differently for each age group during 4 years of follow-up. For younger workers, change in environment and repetitive movements, for middle age team support and for older workers change in awkward posture were significant predictors of MSD risk. These results support the need for workplace-specific hazard surveillance data. This will ensure that all contributing factors to MSD risk can be accurately identified and controlled independent of age.

Immunohistological Analysis of Intracoronary Thrombus Aspirate in STEMI Patients: Clinical Implications of Pathological Findings.

PubMed

Blasco, Ana; Bellas, Carmen; Goicolea, Leyre; Muñiz, Ana; Abraira, Víctor; Royuela, Ana; Mingo, Susana; Oteo, Juan Francisco; García-Touchard, Arturo; Goicolea, Francisco Javier

2017-03-01

Thrombus aspiration allows analysis of intracoronary material in patients with ST-segment elevation myocardial infarction. Our objective was to characterize this material by immunohistology and to study its possible association with patient progress. This study analyzed a prospective cohort of 142 patients undergoing primary angioplasty with positive coronary aspiration. Histological examination of aspirated samples included immunohistochemistry stains for the detection of plaque fragments. The statistical analysis comprised histological variables (thrombus age, degree of inflammation, presence of plaque), the patients' clinical and angiographic features, estimation of survival curves, and logistic regression analysis. Among the histological markers, only the presence of plaque (63% of samples) was associated with postinfarction clinical events. Factors associated with 5-year event-free survival were the presence of plaque in the aspirate (82.2% vs 66.0%; P = .033), smoking (82.5% smokers vs 66.7% nonsmokers; P = .036), culprit coronary artery (83.3% circumflex or right coronary artery vs 68.5% anterior descending artery; P = .042), final angiographic flow (80.8% II-III vs 30.0% 0-I; P < .001) and left ventricular ejection fraction ≥ 35% at discharge (83.7% vs 26.7%; P < .001). On multivariable Cox regression analysis with these variables, independent predictors of event-free survival were the presence of plaque (hazard ratio, 0.37; 95%CI, 0.18-0.77; P = .008), and left ventricular ejection fraction (hazard ratio, 0.92; 95%CI, 0.88-0.95; P < .001). The presence of plaque in the coronary aspirate of patients with ST elevation myocardial infarction may be an independent prognostic marker. CD68 immunohistochemical stain is a good method for plaque detection. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Regression analysis of case K interval-censored failure time data in the presence of informative censoring.

PubMed

Wang, Peijie; Zhao, Hui; Sun, Jianguo

2016-12-01

Interval-censored failure time data occur in many fields such as demography, economics, medical research, and reliability and many inference procedures on them have been developed (Sun, 2006; Chen, Sun, and Peace, 2012). However, most of the existing approaches assume that the mechanism that yields interval censoring is independent of the failure time of interest and it is clear that this may not be true in practice (Zhang et al., 2007; Ma, Hu, and Sun, 2015). In this article, we consider regression analysis of case K interval-censored failure time data when the censoring mechanism may be related to the failure time of interest. For the problem, an estimated sieve maximum-likelihood approach is proposed for the data arising from the proportional hazards frailty model and for estimation, a two-step procedure is presented. In the addition, the asymptotic properties of the proposed estimators of regression parameters are established and an extensive simulation study suggests that the method works well. Finally, we apply the method to a set of real interval-censored data that motivated this study. © 2016, The International Biometric Society.

Hemoglobin Concentration and Risk of Incident Stroke in Community-Living Adults.

PubMed

Panwar, Bhupesh; Judd, Suzanne E; Warnock, David G; McClellan, William M; Booth, John N; Muntner, Paul; Gutiérrez, Orlando M

2016-08-01

In previous observational studies, hemoglobin concentrations have been associated with an increased risk of stroke. However, these studies were limited by a relatively low number of stroke events, making it difficult to determine whether the association of hemoglobin and stroke differed by demographic or clinical factors. Using Cox proportional hazards analysis and Kaplan-Meier plots, we examined the association of baseline hemoglobin concentrations with incident stroke in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, a cohort of black and white adults aged ≥45 years. A total of 518 participants developed stroke over a mean 7±2 years of follow-up. There was a statistically significant interaction between hemoglobin and sex (P=0.05) on the risk of incident stroke. In Cox regression models adjusted for demographic and clinical variables, there was no association of baseline hemoglobin concentration with incident stroke in men, whereas in women, the lowest (<12.4 g/dL) and highest (>14.0 g/dL) quartiles of hemoglobin were associated with higher risk of stroke when compared with the second quartile (12.4-13.2 g/dL; quartile 1: hazard ratio, 1.59; 95% confidence interval, 1.09-2.31; quartile 2: referent; quartile 3: hazard ratio, 0.91; 95% confidence interval, 0.59-1.38; quartile 4: hazard ratio, 1.59; 95% confidence interval, 1.08-2.35). Similar results were observed in models stratified by hemoglobin and sex and when hemoglobin was modeled as a continuous variable using restricted quadratic spline regression. Lower and higher hemoglobin concentrations were associated with a higher risk of incident stroke in women. No such associations were found in men. © 2016 American Heart Association, Inc.

Comparison between a Weibull proportional hazards model and a linear model for predicting the genetic merit of US Jersey sires for daughter longevity.

PubMed

Caraviello, D Z; Weigel, K A; Gianola, D

2004-05-01

Predicted transmitting abilities (PTA) of US Jersey sires for daughter longevity were calculated using a Weibull proportional hazards sire model and compared with predictions from a conventional linear animal model. Culling data from 268,008 Jersey cows with first calving from 1981 to 2000 were used. The proportional hazards model included time-dependent effects of herd-year-season contemporary group and parity by stage of lactation interaction, as well as time-independent effects of sire and age at first calving. Sire variances and parameters of the Weibull distribution were estimated, providing heritability estimates of 4.7% on the log scale and 18.0% on the original scale. The PTA of each sire was expressed as the expected risk of culling relative to daughters of an average sire. Risk ratios (RR) ranged from 0.7 to 1.3, indicating that the risk of culling for daughters of the best sires was 30% lower than for daughters of average sires and nearly 50% lower than than for daughters of the poorest sires. Sire PTA from the proportional hazards model were compared with PTA from a linear model similar to that used for routine national genetic evaluation of length of productive life (PL) using cross-validation in independent samples of herds. Models were compared using logistic regression of daughters' stayability to second, third, fourth, or fifth lactation on their sires' PTA values, with alternative approaches for weighting the contribution of each sire. Models were also compared using logistic regression of daughters' stayability to 36, 48, 60, 72, and 84 mo of life. The proportional hazards model generally yielded more accurate predictions according to these criteria, but differences in predictive ability between methods were smaller when using a Kullback-Leibler distance than with other approaches. Results of this study suggest that survival analysis methodology may provide more accurate predictions of genetic merit for longevity than conventional linear models.

Physical Activity in Advanced Age: Physical Activity, Function, and Mortality in Advanced Age: A Longitudinal Follow Up (LiLACS NZ).

PubMed

Mace Firebaugh, Casey; Moyes, Simon; Jatrana, Santosh; Rolleston, Anna; Kerse, Ngaire

2018-01-18

The relationship between physical activity, function, and mortality is not established in advanced age. Physical activity, function, and mortality were followed in a cohort of Māori and non-Māori adults living in advanced age for a period of six years. Generalised Linear regression models were used to analyse the association between physical activity and NEADL while Kaplan-Meier survival analysis, and Cox-proportional hazard models were used to assess the association between the physical activity and mortality. The Hazard Ratio for mortality for those in the least active physical activity quartile was 4.1 for Māori and 1.8 for non- Māori compared to the most active physical activity quartile. There was an inverse relationship between physical activity and mortality, with lower hazard ratios for mortality at all levels of physical activity. Higher levels of physical activity were associated with lower mortality and higher functional status in advanced aged adults.

An interdisciplinary perspective on social and physical determinants of seismic risk

NASA Astrophysics Data System (ADS)

Lin, K.-H.; Chang, Y.-C.; Liu, G.-Y.; Chan, C.-H.; Lin, T.-H.; Yeh, C.-H.

2015-01-01

While disaster studies researchers usually view risk as a function of hazard, exposure, and vulnerability, few studies have systematically examined the relationships among the various physical and socioeconomic determinants underlying disasters, and fewer have done so through seismic risk analysis. In the context of the 1999 Chi-Chi earthquake in Taiwan, this study constructs five hypothetical models to test different determinants that affect disaster fatality at the village level, namely seismic hazard intensity, population, building fragility, demographics and socioeconomics. The Poisson Regression Model is used to estimate the impact of natural hazards and social factors on fatality. Results indicate that although all of the determinants have an impact on the specific dimension of seismic fatality, some indicators of social inequality, such as gender ratio, dependency ratio, income and its SD, are the driving determinants deteriorating vulnerability to seismic risk. These findings have strong social implications for policy interventions to mitigate such disasters. This study presents an interdisciplinary investigation into social and physical determinants in seismic risk.

Trimethoprim use in early pregnancy and the risk of miscarriage: a register-based nationwide cohort study.

PubMed

Andersen, J T; Petersen, M; Jimenez-Solem, E; Broedbaek, K; Andersen, E W; Andersen, N L; Afzal, S; Torp-Pedersen, C; Keiding, N; Poulsen, H E

2013-08-01

The antibiotic trimethoprim acts as a folate antagonist. Since trophoblasts are very sensitive to drugs that interfere with the folic acid cycle and thereby inhibit DNA synthesis, use of trimethoprim during the first trimester could be associated with miscarriage. A nationwide cohort study including all women in Denmark with a registered pregnancy between 1997 and 2005 was conducted. We used nationwide registers to identify all women giving birth, having a record of miscarriage or induced abortion. Data on exposure to trimethoprim were obtained from the National Prescription Register. Cox proportional hazard regression analysis with exposure to trimethoprim as a time-dependent variable was used to estimate the risk of miscarriage. The adjusted hazard ratio of having a miscarriage after exposure to trimethoprim in the first trimester compared to non-exposure was 2∙04 (95% confidence interval 1∙43-2∙91). Our results indicate that trimethoprim exposure in the first trimester is associated with a doubling of the hazard of miscarriage.

Tuberculosis-related knowledge is associated with patient outcomes in shantytown residents; results from a cohort study, Peru.

PubMed

Westerlund, Emma E; Tovar, Marco A; Lönnermark, Elisabet; Montoya, Rosario; Evans, Carlton A

2015-09-01

Tuberculosis is frequent among poor and marginalized people whose limited tuberculosis-related knowledge may impair healthcare access. We characterised tuberculosis-related knowledge and associations with delayed treatment and treatment outcome. Tuberculosis patients (n = 943), people being tested for suspected tuberculosis (n = 2020), and randomly selected healthy controls (n = 476) in 16 periurban shantytowns were interviewed characterizing: socio-demographic factors; tuberculosis risk-factors; and patients' treatment delay. Principle component analysis was used to generate a tuberculosis-related knowledge score. Patients were followed-up for median 7.7 years. Factors associated with tuberculosis treatment delay, treatment outcome and tuberculosis recurrence were assessed using linear, logistic and Cox regression. Tuberculosis-related knowledge was poor, especially in older people who had not completed schooling and had never been diagnosed with tuberculosis. Tuberculosis treatment delay was median 60 days and was more delayed for patients who were poorer, older, had more severe tuberculosis and in only unadjusted analysis with incomplete schooling and low tuberculosis-related knowledge (all p ≤ 0.03). Lower than median tuberculosis-related knowledge was associated with tuberculosis recurrence (unadjusted hazard ratio = 2.1, p = 0.008), and this association was independent of co-morbidities, disease severity and demographic factors (multiple regression adjusted hazard ratio = 2.6, p = 0.008). Low tuberculosis-related knowledge independently predicted tuberculosis recurrence. Thus health education may improve tuberculosis prognosis. Copyright © 2015. Published by Elsevier Ltd.

Analysis of an experiment aimed at improving the reliability of transmission centre shafts.

PubMed

Davis, T P

1995-01-01

Smith (1991) presents a paper proposing the use of Weibull regression models to establish dependence of failure data (usually times) on covariates related to the design of the test specimens and test procedures. In his article Smith made the point that good experimental design was as important in reliability applications as elsewhere, and in view of the current interest in design inspired by Taguchi and others, we pay some attention in this article to that topic. A real case study from the Ford Motor Company is presented. Our main approach is to utilize suggestions in the literature for applying standard least squares techniques of experimental analysis even when there is likely to be nonnormal error, and censoring. This approach lacks theoretical justification, but its appeal is its simplicity and flexibility. For completeness we also include some analysis based on the proportional hazards model, and in an attempt to link back to Smith (1991), look at a Weibull regression model.

Sodium Valproate, a Histone Deacetylase Inhibitor, Is Associated With Reduced Stroke Risk After Previous Ischemic Stroke or Transient Ischemic Attack.

PubMed

Brookes, Rebecca L; Crichton, Siobhan; Wolfe, Charles D A; Yi, Qilong; Li, Linxin; Hankey, Graeme J; Rothwell, Peter M; Markus, Hugh S

2018-01-01

A variant in the histone deacetylase 9 ( HDAC9 ) gene is associated with large artery stroke. Therefore, inhibiting HDAC9 might offer a novel secondary preventative treatment for ischemic stroke. The antiepileptic drug sodium valproate (SVA) is a nonspecific inhibitor of HDAC9. We tested whether SVA therapy given after ischemic stroke was associated with reduced recurrent stroke rate. Data were pooled from 3 prospective studies recruiting patients with previous stroke or transient ischemic attack and long-term follow-up: the South London Stroke Register, The Vitamins to Prevent Stroke Study, and the Oxford Vascular Study. Patients receiving SVA were compared with patients who received antiepileptic drugs other than SVA using survival analysis and Cox Regression. A total of 11 949 patients with confirmed ischemic event were included. Recurrent stroke rate was lower in patient taking SVA (17 of 168) than other antiepileptic drugs (105 of 530; log-rank survival analysis P =0.002). On Cox regression, controlling for potential cofounders, SVA remained associated with reduced stroke (hazard ratio=0.44; 95% confidence interval: 0.3-0.7; P =0.002). A similar result was obtained when patients taking SVA were compared with all cases not taking SVA (Cox regression, hazard ratio=0.47; 95% confidence interval: 0.29-0.77; P =0.003). These results suggest that exposure to SVA, an inhibitor of HDAC, may be associated with a lower recurrent stroke risk although we cannot exclude residual confounding in this study design. This supports the hypothesis that HDAC9 is important in the ischemic stroke pathogenesis and that its inhibition, by SVA or a more specific HDAC9 inhibitor, is worthy of evaluation as a treatment to prevent recurrent ischemic stroke. © 2017 The Authors.

Early Exposure to Recommended Calorie Delivery in the Intensive Care Unit Is Associated With Increased Mortality in Patients With Acute Respiratory Distress Syndrome.

PubMed

Peterson, Sarah J; Lateef, Omar B; Freels, Sally; McKeever, Liam; Fantuzzi, Giamila; Braunschweig, Carol A

2017-06-01

The Intensive Nutrition in Acute Lung Injury: Clinical Trial (INTACT), designed to evaluate outcomes of calorie delivery from acute respiratory distress syndrome (ARDS) diagnosis through hospital discharge, was stopped due to higher mortality in the intervention group. Post hoc analysis found timing and dose of calorie delivery influenced mortality. The objective of this retrospective cohort study was to determine if early vs late calorie exposure changed the hazard of death among a larger sample of patients with ARDS. Adult patients who met the eligibility criteria for INTACT but did not participate were included. Daily calorie delivery was collected from the date INTACT eligibility was determined to extubation or death. Cox proportional hazards regression was used to model the relationship between hazard of hospital death with average calorie exposure received over increasing study days and after day 7. A total of 298 patients were included; overall mortality was 33%. Among patients who remained intubated at 1 week (n = 202), higher kcal/kg received from intensive care unit (ICU) days 1-6 increased hazards of subsequent death on days 7+ (hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.01-1.06); kcal/kg received after ICU day 7 decreased the hazards of death on day 7+ (HR, 0.53; 95% CI, 0.33-0.84). Higher calorie exposure between ICU days 1 and 7 was associated with higher subsequent hazard of mortality, and provision of high-calorie exposure after day 8 decreased the hazards of death.

The Type of Payment and Working Conditions.

PubMed

Rhee, Kyung Yong; Kim, Young Sun; Cho, Yoon Ho

2015-12-01

The type of payment is one of the important factors that has an effect on the health of employees, as a basic working condition. In the conventional research field of occupational safety and health, only the physical, chemical, biological, and ergonomic factors are treated as the main hazardous factors. Managerial factors and basic working conditions such as working hours and the type of payment are neglected. This paper aimed to investigate the association of the type of payment and the exposure to the various hazardous factors as an heuristic study. The third Korean Working Conditions Survey (KWCS) by the Occupational Safety and Health Research Institute in 2011 was used for this study. Among the total sample of 50,032 economically active persons, 34,788 employees were considered for analysis. This study examined the relation between the three types of payment such as basic fixed salary and wage, piece rate, and extra payment for bad and dangerous working conditions and exposure to hazardous factors like vibration, noise, temperature, chemical contact, and working at very high speeds. Multivariate regression analysis was used to measure the effect of the type of payment on working hours exposed to hazards. The result showed that the proportion of employees with a basic fixed salary was 94.5%, the proportion with piece rates was 38.6%, and the proportion who received extra payment for hazardous working conditions was 11.7%. The piece rate was associated with exposure to working with tight deadlines and stressful jobs. This study had some limitations because KWCS was a cross-sectional survey.

Clinical impact of targeted therapies in patients with metastatic clear-cell renal cell carcinoma

PubMed Central

Nerich, Virginie; Hugues, Marion; Paillard, Marie Justine; Borowski, Laëtitia; Nai, Thierry; Stein, Ulrich; Nguyen Tan Hon, Thierry; Montcuquet, Philippe; Maurina, Tristan; Mouillet, Guillaume; Kleinclauss, François; Pivot, Xavier; Limat, Samuel; Thiery-Vuillemin, Antoine

2014-01-01

Introduction The aim of this retrospective clinical study was to assess, in the context of the recent evolution of systemic therapies, the potential effect of targeted therapies on overall survival (OS) of patients with metastatic clear-cell renal cell carcinoma (mccRCC) in daily practice. Patients and methods All consecutive patients with histologically confirmed mccRCC who received systemic therapy between January 2000 and December 2010 in two oncology treatment centers in our Franche-Comté region in eastern France were included in the analysis. The primary end point was OS. The analysis of prognostic factors was performed using a two-step approach: univariate then multivariate analysis with a stepwise Cox proportional hazards regression model. Results For the entire cohort of 111 patients, the median OS was 17 months (95% confidence interval [CI]; 13–22 months) and the two-year OS was 39%. Three prognostic factors were independent predictors of long survival: prior nephrectomy (hazard ratio =0.38 [0.22–0.64], P<0.0001); systemic therapy by targeted therapy (hazard ratio =0.50 [0.31–0.80], P=0.005); and lack of liver metastasis (hazard ratio =0.43 [0.22–0.82], P=0.002). Median OS was 21 months [14–29 months] for patients who received at least one targeted therapy compared with 12 months [7–15 months] for patients who were treated only by immunotherapy agents (P=0.003). Conclusion Our results suggest that targeted therapies are associated with improved OS in comparison with cytokines, which is in line with other publications. PMID:24600236

Statistical power to detect violation of the proportional hazards assumption when using the Cox regression model.

PubMed

Austin, Peter C

2018-01-01

The use of the Cox proportional hazards regression model is widespread. A key assumption of the model is that of proportional hazards. Analysts frequently test the validity of this assumption using statistical significance testing. However, the statistical power of such assessments is frequently unknown. We used Monte Carlo simulations to estimate the statistical power of two different methods for detecting violations of this assumption. When the covariate was binary, we found that a model-based method had greater power than a method based on cumulative sums of martingale residuals. Furthermore, the parametric nature of the distribution of event times had an impact on power when the covariate was binary. Statistical power to detect a strong violation of the proportional hazards assumption was low to moderate even when the number of observed events was high. In many data sets, power to detect a violation of this assumption is likely to be low to modest.

Statistical power to detect violation of the proportional hazards assumption when using the Cox regression model

PubMed Central

Austin, Peter C.

2017-01-01

The use of the Cox proportional hazards regression model is widespread. A key assumption of the model is that of proportional hazards. Analysts frequently test the validity of this assumption using statistical significance testing. However, the statistical power of such assessments is frequently unknown. We used Monte Carlo simulations to estimate the statistical power of two different methods for detecting violations of this assumption. When the covariate was binary, we found that a model-based method had greater power than a method based on cumulative sums of martingale residuals. Furthermore, the parametric nature of the distribution of event times had an impact on power when the covariate was binary. Statistical power to detect a strong violation of the proportional hazards assumption was low to moderate even when the number of observed events was high. In many data sets, power to detect a violation of this assumption is likely to be low to modest. PMID:29321694

Chemical incidents resulted in hazardous substances releases in the context of human health hazards.

PubMed

Pałaszewska-Tkacz, Anna; Czerczak, Sławomir; Konieczko, Katarzyna

2017-02-21

The research purpose was to analyze data concerning chemical incidents in Poland collected in 1999-2009 in terms of health hazards. The data was obtained, using multimodal information technology (IT) system, from chemical incidents reports prepared by rescuers at the scene. The final analysis covered sudden events associated with uncontrolled release of hazardous chemical substances or mixtures, which may potentially lead to human exposure. Releases of unidentified substances where emergency services took action to protect human health or environment were also included. The number of analyzed chemical incidents in 1999-2009 was 2930 with more than 200 different substances released. The substances were classified into 13 groups of substances and mixtures posing analogous risks. Most common releases were connected with non-flammable corrosive liquids, including: hydrochloric acid (199 cases), sulfuric(VI) acid (131 cases), sodium and potassium hydroxides (69 cases), ammonia solution (52 cases) and butyric acid (32 cases). The next group were gases hazardous only due to physico-chemical properties, including: extremely flammable propane-butane (249 cases) and methane (79 cases). There was no statistically significant trend associated with the total number of incidents. Only with the number of incidents with flammable corrosive, toxic and/or harmful liquids, the regression analysis revealed a statistically significant downward trend. The number of victims reported was 1997, including 1092 children and 18 fatalities. The number of people injured, number of incidents and the high 9th place of Poland in terms of the number of Seveso establishments, and 4 times higher number of hazardous industrial establishments not covered by the Seveso Directive justify the need for systematic analysis of hazards and their proper identification. It is advisable enhance health risk assessment, both qualitative and quantitative, by slight modification of the data collection system so as to enable the determination of released chemical concentration and exposed populations. Int J Occup Med Environ Health 2017;30(1):95-110. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Applying Additive Hazards Models for Analyzing Survival in Patients with Colorectal Cancer in Fars Province, Southern Iran

PubMed

Madadizadeh, Farzan; Ghanbarnejad, Amin; Ghavami, Vahid; Zare Bandamiri, Mohammad; Mohammadianpanah, Mohammad

2017-04-01

Introduction: Colorectal cancer (CRC) is a commonly fatal cancer that ranks as third worldwide and third and the fifth in Iranian women and men, respectively. There are several methods for analyzing time to event data. Additive hazards regression models take priority over the popular Cox proportional hazards model if the absolute hazard (risk) change instead of hazard ratio is of primary concern, or a proportionality assumption is not made. Methods: This study used data gathered from medical records of 561 colorectal cancer patients who were admitted to Namazi Hospital, Shiraz, Iran, during 2005 to 2010 and followed until December 2015. The nonparametric Aalen’s additive hazards model, semiparametric Lin and Ying’s additive hazards model and Cox proportional hazards model were applied for data analysis. The proportionality assumption for the Cox model was evaluated with a test based on the Schoenfeld residuals and for test goodness of fit in additive models, Cox-Snell residual plots were used. Analyses were performed with SAS 9.2 and R3.2 software. Results: The median follow-up time was 49 months. The five-year survival rate and the mean survival time after cancer diagnosis were 59.6% and 68.1±1.4 months, respectively. Multivariate analyses using Lin and Ying’s additive model and the Cox proportional model indicated that the age of diagnosis, site of tumor, stage, and proportion of positive lymph nodes, lymphovascular invasion and type of treatment were factors affecting survival of the CRC patients. Conclusion: Additive models are suitable alternatives to the Cox proportionality model if there is interest in evaluation of absolute hazard change, or no proportionality assumption is made. Creative Commons Attribution License

Survival analysis of cervical cancer using stratified Cox regression

NASA Astrophysics Data System (ADS)

Purnami, S. W.; Inayati, K. D.; Sari, N. W. Wulan; Chosuvivatwong, V.; Sriplung, H.

2016-04-01

Cervical cancer is one of the mostly widely cancer cause of the women death in the world including Indonesia. Most cervical cancer patients come to the hospital already in an advanced stadium. As a result, the treatment of cervical cancer becomes more difficult and even can increase the death's risk. One of parameter that can be used to assess successfully of treatment is the probability of survival. This study raises the issue of cervical cancer survival patients at Dr. Soetomo Hospital using stratified Cox regression based on six factors such as age, stadium, treatment initiation, companion disease, complication, and anemia. Stratified Cox model is used because there is one independent variable that does not satisfy the proportional hazards assumption that is stadium. The results of the stratified Cox model show that the complication variable is significant factor which influent survival probability of cervical cancer patient. The obtained hazard ratio is 7.35. It means that cervical cancer patient who has complication is at risk of dying 7.35 times greater than patient who did not has complication. While the adjusted survival curves showed that stadium IV had the lowest probability of survival.

Employee impact and attitude analysis for GHS implementation in Taiwan.

PubMed

Chang, Yi-Kuo; Su, Teh-Sheng; Ouyang, Yun; Tseng, Jo-Ming

2013-01-01

The employee impact and attitude analysis for GHS implementation in Taiwan was investigated in this study. An impact assessment on the new regulations or changes in regulations for government, potential costs, benefits, and the global trade in chemicals to industries and hazard communication program for workers was studied by the methods of the questionnaire design and Delphi expert method. A survey was conducted using questionnaires and taking 200 experts from government's expert database and 500 selected respondents from case company. Results from present study revealed that the barrier associated with GHS implementation is existed; it is feasible to overcome. Both experts and employees think that business entities are insufficient to test and classify chemicals on their own, and the technical guidance from the government is needed. Data analyzed by the logistic regression revealed that more hours an employee spends on education and trainings of new GHS systems; the employee thinks implementation of GHS will improve hazard awareness for transporters. The weak labeling ability affects deployment of the new GHS system.

Older Patients With Early-stage Breast Cancer: Adjuvant Radiation Therapy and Predictive Factors for Cancer-related Death.

PubMed

Nagar, Himanshu; Yan, Weisi; Christos, Paul; Chao, K S Clifford; Nori, Dattatreyudu; Ravi, Akkamma

2017-06-01

Studies have shown that older women are undertreated for breast cancer. Few data are available on cancer-related death in elderly women aged 70 years and older with pathologic stage T1a-b N0 breast cancer and the impact of prognostic factors on cancer-related death. The Surveillance, Epidemiology, and End Results (SEER) database was queried for women aged 70 years or above diagnosed with pT1a or pT1b, N0 breast cancer who underwent breast conservation surgery from 1999 to 2003. The Kaplan-Meier survival analysis was performed to evaluate breast cause-specific survival (CSS) and overall survival (OS), and the log-rank test was employed to compare CSS/OS between different groups of interest. Multivariable analysis (MVA), using Cox proportional hazards regression analysis, was performed to evaluate the independent effect of age, race, stage, grade, ER status, and radiation treatment on CSS. Adjusted hazard ratios were calculated from the MVA and reflect the increased risk of breast cancer death. Competing-risks survival regression was also performed to adjust the univariate and multivariable CSS hazard ratios for the competing event of death due to causes other than breast cancer. Patients aged 85 and above had a greater risk of breast cancer death compared with patients aged 70 to 74 years (referent category) (adjusted hazard ratio [HRs]=1.98). Race had no effect on CSS. Patients with stage T1bN0 breast cancer had a greater risk of breast cancer death compared with stage T1aN0 patients (adjusted HR=1.35; P=0.09). ER negative patients had a greater risk of breast cancer death compared with ER positive patients (adjusted HR=1.59; P<0.017). Patients with higher grade tumors had a greater risk of breast cancer death compared with patients with grade 1 tumors (referent category) (adjusted HRs=1.69 and 2.96 for grade 2 and 3, respectively). Patients who underwent radiation therapy had a lower risk of breast cancer death compared with patients who did not (adjusted HR=0.55; P<0.0001). Older patients with higher grade, pT1b, ER-negative breast cancer had increased risk of breast cancer-related death. Adjuvant radiation therapy may provide a CSS benefit in this elderly patient population.

Brick mortar exposure and chronic lymphocytic leukemia.

PubMed

Markovic-Denic, L; Jankovic, S; Marinkovic, J; Radovanovic, Z

1995-01-01

A case-control study of 130 patients with chronic lymphocytic leukemia (CLL) and 130 controls matched with respect to sex, age (2 years), type of residence (urban-rural) and area of residence (according to the national per capita income) was carried out. Conditional logistic regression analysis showed that, apart of four risk factors already described in the literature (work in a hazardous industry, hair dye use, family history of leukemia and exposure to electromagnetic radiation), brick mortar exposure was also significantly related to CLL.

A retrospective analysis of the role of proton pump inhibitors in colorectal cancer disease survival

PubMed Central

Graham, C.; Orr, C.; Bricks, C.S.; Hopman, W.M.; Hammad, N.; Ramjeesingh, R.

2016-01-01

Background Proton pump inhibitors (ppis) are a commonly used medication. A limited number of studies have identified a weak-to-moderate association between ppi use and colorectal cancer (crc) risk, but none to date have identified an effect of ppi use on crc survival. We therefore postulated that an association between ppi use and crc survival might potentially exist. Methods We performed a retrospective chart review of 1304 crc patients diagnosed from January 2005 to December 2011 and treated at the Cancer Centre of Southeastern Ontario. Kaplan–Meier analysis and Cox proportional hazards regression models were used to evaluate overall survival (os). Results We identified 117 patients (9.0%) who were taking ppis at the time of oncology consult. Those taking a ppi were also more often taking asa or statins (or both) and had a statistically significantly increased rate of cardiac disease. No identifiable difference in tumour characteristics was evident in the two groups, including tumour location, differentiation, lymph node status, and stage. Univariate analysis identified a statistically nonsignificant difference in survival, with those taking a ppi experiencing lesser 1-year (82.1% vs. 86.7%, p = 0.161), 2-year (70.1% vs. 76.8%, p = 0.111), and 5-year os (55.2% vs. 62.9%, p = 0.165). When controlling for patient demographics and tumour characteristics, multivariate Cox regression analysis identified a statistically significant effect of ppi in our patient population (hazard ratio: 1.343; 95% confidence interval: 1.011 to 1.785; p = 0.042). Conclusions Our results suggest a potential adverse effect of ppi use on os in crc patients. These results need further evaluation in prospective analyses. PMID:28050148

[High Pressure Gas Tanks

NASA Technical Reports Server (NTRS)

Quintana, Rolando

2002-01-01

Four high-pressure gas tanks, the basis of this study, were especially made by a private contractor and tested before being delivered to NASA Kennedy Space Center. In order to insure 100% reliability of each individual tank the staff at KSC decided to again submit the four tanks under more rigorous tests. These tests were conducted during a period from April 10 through May 8 at KSC. This application further validates the predictive safety model for accident prevention and system failure in the testing of four high-pressure gas tanks at Kennedy Space Center, called Continuous Hazard Tracking and Failure Prediction Methodology (CHTFPM). It is apparent from the variety of barriers available for a hazard control that some barriers will be more successful than others in providing protection. In order to complete the Barrier Analysis of the system, a Task Analysis and a Biomechanical Study were performed to establish the relationship between the degree of biomechanical non-conformities and the anomalies found within the system on particular joints of the body. This relationship was possible to obtain by conducting a Regression Analysis to the previously generated data. From the information derived the body segment with the lowest percentage of non-conformities was the neck flexion with 46.7%. Intense analysis of the system was conducted including Preliminary Hazard Analysis (PHA), Failure Mode and Effect Analysis (FMEA), and Barrier Analysis. These analyses resulted in the identification of occurrences of conditions, which may be becoming hazardous in the given system. These conditions, known as dendritics, may become hazards and could result in an accident, system malfunction, or unacceptable risk conditions. A total of 56 possible dendritics were identified. Work sampling was performed to observe the occurrence each dendritic. The out of control points generated from a Weighted c control chart along with a Pareto analysis indicate that the dendritics "Personnel not Wearing Proper Protective and Hose/tubing located in high-traffic area" which account for 59.18% of total dendritic frequency need to be addressed to reduce the chance of a hazard from occurring. However, the occurrences of some dendritics are more important than others. As a result immediate, from a Weighted c perspective, corrective action should be taken to ameliorate the cause of the Class A dendritic "Personnel located under suspended or moving loads" rather than just the most commonly occurring dendritics. In any case the vast majority of data obtained indicates that testing operations possess a relatively high degree of safety.

Correction of Selection Bias in Survey Data: Is the Statistical Cure Worse Than the Bias?

PubMed

Hanley, James A

2017-03-15

In previous articles in the American Journal of Epidemiology (Am J Epidemiol. 2013;177(5):431-442) and American Journal of Public Health (Am J Public Health. 2013;103(10):1895-1901), Masters et al. reported age-specific hazard ratios for the contrasts in mortality rates between obesity categories. They corrected the observed hazard ratios for selection bias caused by what they postulated was the nonrepresentativeness of the participants in the National Health Interview Study that increased with age, obesity, and ill health. However, it is possible that their regression approach to remove the alleged bias has not produced, and in general cannot produce, sensible hazard ratio estimates. First, one must consider how many nonparticipants there might have been in each category of obesity and of age at entry and how much higher the mortality rates would have to be in nonparticipants than in participants in these same categories. What plausible set of numerical values would convert the ("biased") decreasing-with-age hazard ratios seen in the data into the ("unbiased") increasing-with-age ratios that they computed? Can these values be encapsulated in (and can sensible values be recovered from) 1 additional internal variable in a regression model? Second, one must examine the age pattern of the hazard ratios that have been adjusted for selection. Without the correction, the hazard ratios are attenuated with increasing age. With it, the hazard ratios at older ages are considerably higher, but those at younger ages are well below 1. Third, one must test whether the regression approach suggested by Masters et al. would correct the nonrepresentativeness that increased with age and ill health that I introduced into real and hypothetical data sets. I found that the approach did not recover the hazard ratio patterns present in the unselected data sets: The corrections overshot the target at older ages and undershot it at lower ages. © The Author 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

Censored quantile regression with recursive partitioning-based weights

PubMed Central

Wey, Andrew; Wang, Lan; Rudser, Kyle

2014-01-01

Censored quantile regression provides a useful alternative to the Cox proportional hazards model for analyzing survival data. It directly models the conditional quantile of the survival time and hence is easy to interpret. Moreover, it relaxes the proportionality constraint on the hazard function associated with the popular Cox model and is natural for modeling heterogeneity of the data. Recently, Wang and Wang (2009. Locally weighted censored quantile regression. Journal of the American Statistical Association 103, 1117–1128) proposed a locally weighted censored quantile regression approach that allows for covariate-dependent censoring and is less restrictive than other censored quantile regression methods. However, their kernel smoothing-based weighting scheme requires all covariates to be continuous and encounters practical difficulty with even a moderate number of covariates. We propose a new weighting approach that uses recursive partitioning, e.g. survival trees, that offers greater flexibility in handling covariate-dependent censoring in moderately high dimensions and can incorporate both continuous and discrete covariates. We prove that this new weighting scheme leads to consistent estimation of the quantile regression coefficients and demonstrate its effectiveness via Monte Carlo simulations. We also illustrate the new method using a widely recognized data set from a clinical trial on primary biliary cirrhosis. PMID:23975800

Study of Rapid-Regression Liquefying Hybrid Rocket Fuels

NASA Technical Reports Server (NTRS)

Zilliac, Greg; DeZilwa, Shane; Karabeyoglu, M. Arif; Cantwell, Brian J.; Castellucci, Paul

2004-01-01

A report describes experiments directed toward the development of paraffin-based hybrid rocket fuels that burn at regression rates greater than those of conventional hybrid rocket fuels like hydroxyl-terminated butadiene. The basic approach followed in this development is to use materials such that a hydrodynamically unstable liquid layer forms on the melting surface of a burning fuel body. Entrainment of droplets from the liquid/gas interface can substantially increase the rate of fuel mass transfer, leading to surface regression faster than can be achieved using conventional fuels. The higher regression rate eliminates the need for the complex multi-port grain structures of conventional solid rocket fuels, making it possible to obtain acceptable performance from single-port structures. The high-regression-rate fuels contain no toxic or otherwise hazardous components and can be shipped commercially as non-hazardous commodities. Among the experiments performed on these fuels were scale-up tests using gaseous oxygen. The data from these tests were found to agree with data from small-scale, low-pressure and low-mass-flux laboratory tests and to confirm the expectation that these fuels would burn at high regression rates, chamber pressures, and mass fluxes representative of full-scale rocket motors.

Marital status and survival in patients with renal cell carcinoma.

PubMed

Li, Yan; Zhu, Ming-Xi; Qi, Si-Hua

2018-04-01

Previous studies have shown that marital status is an independent prognostic factor for survival in several types of cancer. In this study, we investigated the effects of marital status on survival outcomes among renal cell carcinoma (RCC) patients.We identified patients diagnosed with RCC between 1973 and 2013 from the Surveillance, Epidemiology and End Results (SEER) database. Kaplan-Meier analysis and Cox regression were used to identify the effects of marital status on overall survival (OS) and cancer-specific survival (CSS).We enrolled 97,662 eligible RCC patients, including 64,884 married patients, and 32,778 unmarried (9831 divorced/separated, 9692 widowed, and 13,255 single) patients at diagnosis. The 5-year OS and CSS rates of the married, separated/divorced, widowed, and single patients were 73.7%, 69.5%, 58.3%, and 73.2% (OS), and 82.2%, 80.7%, 75.7%, and 83.3% (CSS), respectively. Multivariate Cox regression showed that, compared with married patients, widowed individuals showed poorer OS (hazard ratio, 1.419; 95% confidence interval, 1.370-1.469) and CSS (hazard ratio, 1.210; 95% confidence interval, 1.144-1.279). Stratified analyses and multivariate Cox regression showed that, in the insured and uninsured groups, married patients had better survival outcomes while widowed patients suffered worse OS outcomes; however, this trend was not significant for CSS.In RCC patients, married patients had better survival outcomes while widowed patients tended to suffer worse survival outcomes in terms of both OS and CSS.

Marital status and survival in patients with renal cell carcinoma

PubMed Central

Li, Yan; Zhu, Ming-xi; Qi, Si-hua

2018-01-01

Abstract Previous studies have shown that marital status is an independent prognostic factor for survival in several types of cancer. In this study, we investigated the effects of marital status on survival outcomes among renal cell carcinoma (RCC) patients. We identified patients diagnosed with RCC between 1973 and 2013 from the Surveillance, Epidemiology and End Results (SEER) database. Kaplan–Meier analysis and Cox regression were used to identify the effects of marital status on overall survival (OS) and cancer-specific survival (CSS). We enrolled 97,662 eligible RCC patients, including 64,884 married patients, and 32,778 unmarried (9831 divorced/separated, 9692 widowed, and 13,255 single) patients at diagnosis. The 5-year OS and CSS rates of the married, separated/divorced, widowed, and single patients were 73.7%, 69.5%, 58.3%, and 73.2% (OS), and 82.2%, 80.7%, 75.7%, and 83.3% (CSS), respectively. Multivariate Cox regression showed that, compared with married patients, widowed individuals showed poorer OS (hazard ratio, 1.419; 95% confidence interval, 1.370–1.469) and CSS (hazard ratio, 1.210; 95% confidence interval, 1.144–1.279). Stratified analyses and multivariate Cox regression showed that, in the insured and uninsured groups, married patients had better survival outcomes while widowed patients suffered worse OS outcomes; however, this trend was not significant for CSS. In RCC patients, married patients had better survival outcomes while widowed patients tended to suffer worse survival outcomes in terms of both OS and CSS. PMID:29668592

Increased risk of tinnitus in patients with chronic kidney disease: A nationwide, population-based cohort study.

PubMed

Shih, Cheng-Ping; Lin, Hung-Che; Chung, Chi-Hsiang; Hsiao, Po-Jen; Wang, Chih-Hung; Lee, Jih-Chin; Chien, Wu-Chien

2017-01-01

Tinnitus mostly results from central and peripheral auditory pathology. Chronic kidney disease (CKD) is a major risk factor for cerebrovascular disease. However, no studies have evaluated the association between tinnitus and CKD. The aim of this study is to investigate the risk of tinnitus in patients with CKD. This retrospective cohort study was conducted using Taiwan National Health Insurance Research Database from 2000 to 2010. We established a CKD group (n = 185,430) and a non-CKD comparison group (n = 556,290) to investigate the incidence of tinnitus. Cox proportional hazard regression analysis was used to evaluate the effects of CKD on tinnitus risk. The results showed CKD significantly increased the risk of tinnitus (adjusted hazard ratio, 3.02; 95% CI, 2.655-3.456, P<0.001). A subgroup analysis revealed the increase in risk of tinnitus is more in CKD patients with heart failure (adjusted hazard ratio, 9.975; 95% CI, 5.001-18.752) and diabetes mellitus (adjusted hazard ratio, 3.712; 95% CI, 2.856-5.007). Furthermore, compared to non-CKD patients, the risk of tinnitus was increased 4.586-fold (95% CI, 2.399-6.7) in CKD patients with dialysis and 2.461-fold (95% CI, 1.033-3.454) in CKD patients without dialysis. This study is the first to report that CKD is associated with an increased risk of tinnitus. Among CKD cohort, patients with dialysis are at a higher risk of tinnitus than those without dialysis.

Risk of Revision Was Not Reduced by a Double-bundle ACL Reconstruction Technique: Results From the Scandinavian Registers.

PubMed

Aga, Cathrine; Kartus, Jüri-Tomas; Lind, Martin; Lygre, Stein Håkon Låstad; Granan, Lars-Petter; Engebretsen, Lars

2017-10-01

Double-bundle anterior cruciate ligament (ACL) reconstruction has demonstrated improved biomechanical properties and moderately better objective outcomes compared with single-bundle reconstructions. This could make an impact on the rerupture rate and reduce the risk of revisions in patients undergoing double-bundle ACL reconstruction compared with patients reconstructed with a traditional single-bundle technique. The National Knee Ligament Registers in Scandinavia provide information that can be used to evaluate the revision outcome after ACL reconstructions. The purposes of the study were (1) to compare the risk of revision between double-bundle and single-bundle reconstructions, reconstructed with autologous hamstring tendon grafts; (2) to compare the risk of revision between double-bundle hamstring tendon and single-bundle bone-patellar tendon-bone autografts; and (3) to compare the hazard ratios for the same two research questions after Cox regression analysis was performed. Data collection of primary ACL reconstructions from the National Knee Ligament Registers in Denmark, Norway, and Sweden from July 1, 2005, to December 31, 2014, was retrospectively analyzed. A total of 60,775 patients were included in the study; 994 patients were reconstructed with double-bundle hamstring tendon grafts, 51,991 with single-bundle hamstring tendon grafts, and 7790 with single-bundle bone-patellar tendon-bone grafts. The double-bundle ACL-reconstructed patients were compared with the two other groups. The risk of revision for each research question was detected by the risk ratio, hazard ratio, and the corresponding 95% confidence intervals. Kaplan-Meier analysis was used to estimate survival at 1, 2, and 5 years for the three different groups. Furthermore, a Cox proportional hazard regression model was applied and the hazard ratios were adjusted for country, age, sex, meniscal or chondral injury, and utilized fixation devices on the femoral and tibial sides. There were no differences in the crude risk of revision between the patients undergoing the double-bundle technique and the two other groups. A total of 3.7% patients were revised in the double-bundle group (37 of 994 patients) versus 3.8% in the single-bundle hamstring tendon group (1952 of 51,991; risk ratio, 1.01; 95% confidence interval (CI), 0.73-1.39; p = 0.96), and 2.8% of the patients were revised in the bone-patellar tendon-bone group (219 of the 7790 bone-patellar tendon-bone patients; risk ratio, 0.76; 95% CI, 0.54-1.06; p = 0.11). Cox regression analysis with adjustment for country, age, sex, menisci or cartilage injury, and utilized fixation device on the femoral and tibial sides, did not reveal any further difference in the risk of revision between the single-bundle hamstring tendon and double-bundle hamstring tendon groups (hazard ratio, 1.18; 95% CI, 0.85-1.62; p = 0.33), but the adjusted hazard ratio showed a lower risk of revision in the single-bundle bone-patellar tendon-bone group compared with the double-bundle group (hazard ratio, 0.62; 95% CI, 0.43-0.90; p = 0.01). Comparisons of the graft revision rates reported separately for each country revealed that double-bundle hamstring tendon reconstructions in Sweden had a lower hazard ratio compared with the single-bundle hamstring tendon reconstructions (hazard ratio, 1.00 versus 1.89; 95% CI, 1.09-3.29; p = 0.02). Survival at 5 years after index surgery was 96.0% for the double-bundle group, 95.4% for the single-bundle hamstring tendon group, and 97.0% for the single-bundle bone-patellar tendon-bone group. Based on the data from all three national registers, the risk of revision was not influenced by the reconstruction technique in terms of using single- or double-bundle hamstring tendons, although national differences in survival existed. Using bone-patellar tendon-bone grafts lowered the risk of revision compared with double-bundle hamstring tendon grafts. These findings should be considered when deciding what reconstruction technique to use in ACL-deficient knees. Future studies identifying the reasons for graft rerupture in single- and double-bundle reconstructions would be of interest to understand the findings of the present study. Level III, therapeutic study.

Water and growth: An econometric analysis of climate and policy impacts

NASA Astrophysics Data System (ADS)

Khan, Hassaan Furqan; Morzuch, Bernard J.; Brown, Casey M.

2017-06-01

Water-related hazards such as floods, droughts, and disease cause damage to an economy through the destruction of physical capital including property and infrastructure, the loss of human capital, and the interruption of economic activities, like trade and education. The question for policy makers is whether the impacts of water-related risk accrue to manifest as a drag on economic growth at a scale suggesting policy intervention. In this study, the average drag on economic growth from water-related hazards faced by society at a global level is estimated. We use panel regressions with various specifications to investigate the relationship between economic growth and hydroclimatic variables at the country-river basin level. In doing so, we make use of surface water runoff variables never used before. The analysis of the climate variables shows that water availability and water hazards have significant effects on economic growth, providing further evidence beyond earlier studies finding that precipitation extremes were at least as important or likely more important than temperature effects. We then incorporate a broad set of variables representing the areas of infrastructure, institutions, and information to identify the characteristics of a region that determine its vulnerability to water-related risks. The results identify water scarcity, governance, and agricultural intensity as the most relevant measures affecting vulnerabilities to climate variability effects.

The Short-term Prognostic Value of the Triglyceride-to-high-density Lipoprotein Cholesterol Ratio in Acute Ischemic Stroke

PubMed Central

Wang, Huan; Lei, Leix; Zhang, Han-Qing; Gu, Zheng-Tian; Xing, Fang-Lan; Yan, Fu-Ling

2018-01-01

The triglyceride (TG)-to-high-density lipoprotein cholesterol (HDL-C) ratio (TG/HDL-C) is a simple approach to predicting unfavorable outcomes in cardiovascular disease. The influence of TG/HDL-C on acute ischemic stroke remains elusive. The purpose of this study was to investigate the precise effect of TG/HDL-C on 3-month mortality after acute ischemic stroke (AIS). Patients with AIS were enrolled in the present study from 2011 to 2017. A total of 1459 participants from a single city in China were divided into retrospective training and prospective test cohorts. Medical records were collected periodically to determine the incidence of fatal events. All participants were followed for 3 months. Optimal cutoff values were determined using X-tile software to separate the training cohort patients into higher and lower survival groups based on their lipid levels. A survival analysis was conducted using Kaplan-Meier curves and a Cox proportional hazards regression model. A total of 1459 patients with AIS (median age 68.5 years, 58.5% male) were analyzed. Univariate Cox regression analysis confirmed that TG/HDL-C was a significant prognostic factor for 3-month survival. X-tile identified 0.9 as an optimal cutoff for TG/HDL-C. In the univariate analysis, the prognosis of the TG/HDL-C >0.9 group was markedly superior to that of TG/HDL-C ≤0.9 group (P<0.001). A multivariate Cox regression analysis showed that TG/HDL-C was independently correlated with a reduced risk of mortality (hazard ratio [HR], 0.39; 95% confidence interval [CI], 0.24-0.62; P<0.001). These results were confirmed in the 453 patients in the test cohort. A nomogram was constructed to predict 3-month case-fatality, and the c-indexes of predictive accuracy were 0.684 and 0.670 in the training and test cohorts, respectively (P<0.01). The serum TG/HDL-C ratio may be useful for predicting short-term mortality after AIS. PMID:29896437

The Short-term Prognostic Value of the Triglyceride-to-high-density Lipoprotein Cholesterol Ratio in Acute Ischemic Stroke.

PubMed

Deng, Qi-Wen; Li, Shuo; Wang, Huan; Lei, Leix; Zhang, Han-Qing; Gu, Zheng-Tian; Xing, Fang-Lan; Yan, Fu-Ling

2018-06-01

The triglyceride (TG)-to-high-density lipoprotein cholesterol (HDL-C) ratio (TG/HDL-C) is a simple approach to predicting unfavorable outcomes in cardiovascular disease. The influence of TG/HDL-C on acute ischemic stroke remains elusive. The purpose of this study was to investigate the precise effect of TG/HDL-C on 3-month mortality after acute ischemic stroke (AIS). Patients with AIS were enrolled in the present study from 2011 to 2017. A total of 1459 participants from a single city in China were divided into retrospective training and prospective test cohorts. Medical records were collected periodically to determine the incidence of fatal events. All participants were followed for 3 months. Optimal cutoff values were determined using X-tile software to separate the training cohort patients into higher and lower survival groups based on their lipid levels. A survival analysis was conducted using Kaplan-Meier curves and a Cox proportional hazards regression model. A total of 1459 patients with AIS (median age 68.5 years, 58.5% male) were analyzed. Univariate Cox regression analysis confirmed that TG/HDL-C was a significant prognostic factor for 3-month survival. X-tile identified 0.9 as an optimal cutoff for TG/HDL-C. In the univariate analysis, the prognosis of the TG/HDL-C >0.9 group was markedly superior to that of TG/HDL-C ≤0.9 group (P<0.001). A multivariate Cox regression analysis showed that TG/HDL-C was independently correlated with a reduced risk of mortality (hazard ratio [HR], 0.39; 95% confidence interval [CI], 0.24-0.62; P<0.001). These results were confirmed in the 453 patients in the test cohort. A nomogram was constructed to predict 3-month case-fatality, and the c-indexes of predictive accuracy were 0.684 and 0.670 in the training and test cohorts, respectively (P<0.01). The serum TG/HDL-C ratio may be useful for predicting short-term mortality after AIS.

Predictors of mortality in hospital survivors with type 2 diabetes mellitus and acute coronary syndromes.

PubMed

Savonitto, Stefano; Morici, Nuccia; Nozza, Anna; Cosentino, Francesco; Perrone Filardi, Pasquale; Murena, Ernesto; Morocutti, Giorgio; Ferri, Marco; Cavallini, Claudio; Eijkemans, Marinus Jc; Stähli, Barbara E; Schrieks, Ilse C; Toyama, Tadashi; Lambers Heerspink, H J; Malmberg, Klas; Schwartz, Gregory G; Lincoff, A Michael; Ryden, Lars; Tardif, Jean Claude; Grobbee, Diederick E

2018-01-01

To define the predictors of long-term mortality in patients with type 2 diabetes mellitus and recent acute coronary syndrome. A total of 7226 patients from a randomized trial, testing the effect on cardiovascular outcomes of the dual peroxisome proliferator-activated receptor agonist aleglitazar in patients with type 2 diabetes mellitus and recent acute coronary syndrome (AleCardio trial), were analysed. Median follow-up was 2 years. The independent mortality predictors were defined using Cox regression analysis. The predictive information provided by each variable was calculated as percent of total chi-square of the model. All-cause mortality was 4.0%, with cardiovascular death contributing for 73% of mortality. The mortality prediction model included N-terminal proB-type natriuretic peptide (adjusted hazard ratio = 1.68; 95% confidence interval = 1.51-1.88; 27% of prediction), lack of coronary revascularization (hazard ratio = 2.28; 95% confidence interval = 1.77-2.93; 18% of prediction), age (hazard ratio = 1.04; 95% confidence interval = 1.02-1.05; 15% of prediction), heart rate (hazard ratio = 1.02; 95% confidence interval = 1.01-1.03; 10% of prediction), glycated haemoglobin (hazard ratio = 1.11; 95% confidence interval = 1.03-1.19; 8% of prediction), haemoglobin (hazard ratio = 1.01; 95% confidence interval = 1.00-1.02; 8% of prediction), prior coronary artery bypass (hazard ratio = 1.61; 95% confidence interval = 1.11-2.32; 7% of prediction) and prior myocardial infarction (hazard ratio = 1.40; 95% confidence interval = 1.05-1.87; 6% of prediction). In patients with type 2 diabetes mellitus and recent acute coronary syndrome, mortality prediction is largely dominated by markers of cardiac, rather than metabolic, dysfunction.

Race/ethnicity, education, and age are associated with engagement in ecological momentary assessment text messaging among substance-using MSM in San Francisco.

PubMed

Turner, Caitlin M; Coffin, Phillip; Santos, Deirdre; Huffaker, Shannon; Matheson, Tim; Euren, Jason; DeMartini, Anna; Rowe, Chris; Batki, Steven; Santos, Glenn-Milo

2017-04-01

Ecological momentary assessments (EMA) are data collection approaches that characterize behaviors in real-time. However, EMA is underutilized in alcohol and substance use research among men who have sex with men (MSM). The aim of this analysis is to explore the correlates of engagement in EMA text messages among substance-using MSM in San Francisco. The present analysis uses data collected from the Project iN pilot study (n=30). Over a two-month period, participants received and responded to EMA daily text messages inquiring about their study medication, alcohol, and methamphetamine use. Baseline characteristics including demographics, alcohol use, and substance use were examined as potential correlates of engagement in EMA text messages in logistic regression and proportional hazards models. Participants had a 74% response rate to EMA text messages over the study period. MSM of color had significantly lower adjusted odds of responding to EMA texts 80% of the time or more, compared to white MSM (adjusted odds ratio=0.05, 95%CI=0.01-0.38). College-educated MSM had a lower adjusted hazard of week-long discontinuation in EMA texts (adjusted hazard ratio=0.12, 95%CI=0.02-0.63). Older MSM had a higher adjusted hazard of week-long discontinuation in EMA texts (adjusted hazard ratio=1.15, 95%CI=1.01-1.31). Differences in engagement in EMA text prompts were discovered for MSM with different racial/ethnic backgrounds, ages, and education levels. Substance use variables were not correlated with engagement in text messages, suggesting that EMA may be a useful research tool among actively substance-using MSM in San Francisco. Published by Elsevier Inc.

Differences in neurohormonal activity partially explain the obesity paradox in patients with heart failure: The role of sympathetic activation.

PubMed

Farré, Núria; Aranyó, Júlia; Enjuanes, Cristina; Verdú-Rotellar, José María; Ruiz, Sonia; Gonzalez-Robledo, Gina; Meroño, Oona; de Ramon, Marta; Moliner, Pedro; Bruguera, Jordi; Comin-Colet, Josep

2015-02-15

Obese patients with chronic Heart Failure (HF) have better outcome than their lean counterparts, although little is known about the pathophysiology of this obesity paradox. Our aim was to evaluate the hypothesis that patients with chronic HF and obesity (defined as body mass index (BMI)≥30kg/m(2)), may have an attenuated neurohormonal activation in comparison with non-obese patients. The present study is the post-hoc analysis of a cohort of 742 chronic HF patients from a single-center study evaluating sympathetic activation by measuring baseline levels of norepinephrine (NE). Obesity was present in 33% of patients. Higher BMI and obesity were significantly associated with lower NE levels in multivariable linear regression models adjusted for covariates (p<0.001). Addition to NE in multivariate Cox proportional hazard models attenuated the prognostic impact of BMI in terms of outcomes. Finally, when we explored the prognosis impact of raised NE levels (>70th percentile) carrying out a separate analysis in obese and non-obese patients we found that in both groups NE remained a significant independent predictor of poorer outcomes, despite the lower NE levels in patients with chronic HF and obesity: all-cause mortality hazard ratio=2.37 (95% confidence interval, 1.14-4.94) and hazard ratio=1.59 (95% confidence interval, 1.05-2.4) in obese and non-obese respectively; and cardiovascular mortality hazard ratio=3.08 (95% confidence interval, 1.05-9.01) in obese patients and hazard ratio=2.08 (95% confidence interval, 1.42-3.05) in non-obese patients. Patients with chronic HF and obesity have significantly lower sympathetic activation. This finding may partially explain the obesity paradox described in chronic HF patients. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Geospatial Data Integration for Assessing Landslide Hazard on Engineered Slopes

NASA Astrophysics Data System (ADS)

Miller, P. E.; Mills, J. P.; Barr, S. L.; Birkinshaw, S. J.

2012-07-01

Road and rail networks are essential components of national infrastructures, underpinning the economy, and facilitating the mobility of goods and the human workforce. Earthwork slopes such as cuttings and embankments are primary components, and their reliability is of fundamental importance. However, instability and failure can occur, through processes such as landslides. Monitoring the condition of earthworks is a costly and continuous process for network operators, and currently, geospatial data is largely underutilised. The research presented here addresses this by combining airborne laser scanning and multispectral aerial imagery to develop a methodology for assessing landslide hazard. This is based on the extraction of key slope stability variables from the remotely sensed data. The methodology is implemented through numerical modelling, which is parameterised with the slope stability information, simulated climate conditions, and geotechnical properties. This allows determination of slope stability (expressed through the factor of safety) for a range of simulated scenarios. Regression analysis is then performed in order to develop a functional model relating slope stability to the input variables. The remotely sensed raster datasets are robustly re-sampled to two-dimensional cross-sections to facilitate meaningful interpretation of slope behaviour and mapping of landslide hazard. Results are stored in a geodatabase for spatial analysis within a GIS environment. For a test site located in England, UK, results have shown the utility of the approach in deriving practical hazard assessment information. Outcomes were compared to the network operator's hazard grading data, and show general agreement. The utility of the slope information was also assessed with respect to auto-population of slope geometry, and found to deliver significant improvements over the network operator's existing field-based approaches.

Does workplace social capital associate with hazardous drinking among Chinese rural-urban migrant workers?

PubMed

Gao, Junling; Weaver, Scott R; Fua, Hua; Pan, Zhigang

2014-01-01

The present study sought to investigate the associations between workplace social capital and hazardous drinking (HD) among Chinese rural-urban migrant workers (RUMW). A cross sectional study with a multi-stage stratified sampling procedure was conducted in Shanghai during July 2012 to January 2013. In total, 5,318 RUMWs from 77 workplaces were involved. Work-place social capital was assessed using a validated and psychometrically tested eight-item measure. The Chinese version of Alcohol Use Disorders Identification Test (AUDIT) was used to assess hazardous drinking. Control variables included gender, age, marital status, education level, salary, and current smoking. Multilevel logistic regression analysis was conducted to test whether individual- and workplace-level social capital was associated with hazardous drinking. Overall, the prevalence of HD was 10.6%. After controlling for individual-level socio-demographic and lifestyle variables, compared to workers in the highest quartile of individual-level social capital, the odds of HD for workers in the three bottom quartiles were 1.13(95%CI: 1.04-1.23), 1.17(95%CI: 1.05-1.56) and 1.26(95%CI: 1.13-1.72), respectively. However, contrary to hypothesis, there was no relationship between workplace-level social capital and hazardous drinking. Higher individual-level social capital may protect against HD among Chinese RUMWs. Interventions to build individual social capital among RUMWs in China may help reduce HD among this population.

Health related quality of life and influencing factors among welders.

PubMed

Qin, Jingxiang; Liu, Wuzhong; Zhu, Jun; Weng, Wei; Xu, Jiaming; Ai, Zisheng

2014-01-01

Occupational exposure to welding fumes is a serious occupational health problem all over the world. Welders are exposed to many occupational hazards; these hazards might cause some occupational diseases. The aim of the study was to assess the health related quality of life (HRQL) of electric welders in Shanghai China and explore influencing factors to HRQL of welders. 301 male welders (without pneumoconiosis) and 305 non-dust male workers in Shanghai were enrolled in this study. Short Form-36 (SF-36) health survey questionnaires were applied in this cross-sectional study. Socio-demographic, working and health factors were also collected. Multiple stepwise regress analysis was used to identify significant factors related to the eight dimension scores. Six dimensions including role-physical (RP), bodily pain (BP), general health (GH), validity (VT), social function (SF), and mental health (MH) were significantly worse in welders compared to non-dust workers. Multiple stepwise regress analysis results show that native place, monthly income, quantity of children, drinking, sleep time, welding type, use of personal protective equipment (PPE), great events in life, and some symptoms including dizziness, discomfort of cervical vertebra, low back pain, cough and insomnia may be influencing factors for HRQL of welders. Among these factors, only sleep time and the use of PPE were salutary. Some dimensions of HRQL of these welders have been affected. Enterprises which employ welders should take measures to protect the health of these people and improve their HRQL.

Effect and clinical prediction of worsening renal function in acute decompensated heart failure.

PubMed

Breidthardt, Tobias; Socrates, Thenral; Noveanu, Markus; Klima, Theresia; Heinisch, Corinna; Reichlin, Tobias; Potocki, Mihael; Nowak, Albina; Tschung, Christopher; Arenja, Nisha; Bingisser, Roland; Mueller, Christian

2011-03-01

We aimed to establish the prevalence and effect of worsening renal function (WRF) on survival among patients with acute decompensated heart failure. Furthermore, we sought to establish a risk score for the prediction of WRF and externally validate the previously established Forman risk score. A total of 657 consecutive patients with acute decompensated heart failure presenting to the emergency department and undergoing serial creatinine measurements were enrolled. The potential of the clinical parameters at admission to predict WRF was assessed as the primary end point. The secondary end point was all-cause mortality at 360 days. Of the 657 patients, 136 (21%) developed WRF, and 220 patients had died during the first year. WRF was more common in the nonsurvivors (30% vs 41%, p = 0.03). Multivariate regression analysis found WRF to independently predict mortality (hazard ratio 1.92, p <0.01). In a single parameter model, previously diagnosed chronic kidney disease was the only independent predictor of WRF and achieved an area under the receiver operating characteristic curve of 0.60. After the inclusion of the blood gas analysis parameters into the model history of chronic kidney disease (hazard ratio 2.13, p = 0.03), outpatient diuretics (hazard ratio 5.75, p <0.01), and bicarbonate (hazard ratio 0.91, p <0.01) were all predictive of WRF. A risk score was developed using these predictors. On receiver operating characteristic curve analysis, the Forman and Basel prediction rules achieved an area under the curve of 0.65 and 0.71, respectively. In conclusion, WRF was common in patients with acute decompensated heart failure and was linked to significantly worse outcomes. However, the clinical parameters failed to adequately predict its occurrence, making a tailored therapy approach impossible. Copyright © 2011 Elsevier Inc. All rights reserved.

Factors determining disease duration in Alzheimer's disease: a postmortem study of 103 cases using the Kaplan-Meier estimator and Cox regression.

PubMed

Armstrong, R A

2014-01-01

Factors associated with duration of dementia in a consecutive series of 103 Alzheimer's disease (AD) cases were studied using the Kaplan-Meier estimator and Cox regression analysis (proportional hazard model). Mean disease duration was 7.1 years (range: 6 weeks-30 years, standard deviation = 5.18); 25% of cases died within four years, 50% within 6.9 years, and 75% within 10 years. Familial AD cases (FAD) had a longer duration than sporadic cases (SAD), especially cases linked to presenilin (PSEN) genes. No significant differences in duration were associated with age, sex, or apolipoprotein E (Apo E) genotype. Duration was reduced in cases with arterial hypertension. Cox regression analysis suggested longer duration was associated with an earlier disease onset and increased senile plaque (SP) and neurofibrillary tangle (NFT) pathology in the orbital gyrus (OrG), CA1 sector of the hippocampus, and nucleus basalis of Meynert (NBM). The data suggest shorter disease duration in SAD and in cases with hypertensive comorbidity. In addition, degree of neuropathology did not influence survival, but spread of SP/NFT pathology into the frontal lobe, hippocampus, and basal forebrain was associated with longer disease duration.

Time to detection of circulating microbubbles as a risk factor for symptoms of altitude decompression sickness

NASA Technical Reports Server (NTRS)

Kumar, K. V.; Calkins, Dick S.; Waligora, James M.; Gilbert, John H., III; Powell, Michael R.

1992-01-01

This study investigated the association between time at onset of circulating microbubbles (CMB) and symptoms of altitude decompression sickness (DCS), using Cox proportional hazard regression models. The study population consisted of 125 individuals who participated in direct ascent, simulated extravehicular activities profiles. Using individual CMB status as a time-dependent variable, we found that the hazard for symptoms increased significantly (at the end of 180 min at altitude) in the presence of CMB (Hazard Ratio = 29.59; 95 percent confidence interval (95 percent CI) = 7.66-114.27), compared to no CMB. Further examination was conducted on the subgroup of individuals who developed microbubbles during the test (n = 49), by using Cox regression. Individuals with late onset of CMB (greater than 60 min at altitude) showed a significantly reduced risk of symptoms (hazard ratio = 0.92; 95 percent CI = 0.89-0.95), compared to those with early onset (equal to or less than 60 min), while controlling for other risk factors. We conclude that time to detection of circulating microbubbles is an independent determinant of symptoms of DCS.

ELASTIC NET FOR COX'S PROPORTIONAL HAZARDS MODEL WITH A SOLUTION PATH ALGORITHM.

PubMed

Wu, Yichao

2012-01-01

For least squares regression, Efron et al. (2004) proposed an efficient solution path algorithm, the least angle regression (LAR). They showed that a slight modification of the LAR leads to the whole LASSO solution path. Both the LAR and LASSO solution paths are piecewise linear. Recently Wu (2011) extended the LAR to generalized linear models and the quasi-likelihood method. In this work we extend the LAR further to handle Cox's proportional hazards model. The goal is to develop a solution path algorithm for the elastic net penalty (Zou and Hastie (2005)) in Cox's proportional hazards model. This goal is achieved in two steps. First we extend the LAR to optimizing the log partial likelihood plus a fixed small ridge term. Then we define a path modification, which leads to the solution path of the elastic net regularized log partial likelihood. Our solution path is exact and piecewise determined by ordinary differential equation systems.

Impact of Contextual Factors on Prostate Cancer Risk and Outcomes

DTIC Science & Technology

2013-07-01

framework with random effects (“frailty models”) while the case-control analyses (Aim 4) will use multilevel unconditional logistic regression models...contextual-level SES on prostate cancer risk within racial/ethnic groups. The survival analyses (Aims 1-3) will utilize a proportional hazards regression

EXPLORING ENGINEERING CONTROL THROUGH PROCESS MANIPULATION OF RADIOACTIVE LIQUID WASTE TANK CHEMICAL CLEANING

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, A.

2014-04-27

One method of remediating legacy liquid radioactive waste produced during the cold war, is aggressive in-tank chemical cleaning. Chemical cleaning has successfully reduced the curie content of residual waste heels in large underground storage tanks; however this process generates significant chemical hazards. Mercury is often the bounding hazard due to its extensive use in the separations process that produced the waste. This paper explores how variations in controllable process factors, tank level and temperature, may be manipulated to reduce the hazard potential related to mercury vapor generation. When compared using a multivariate regression analysis, findings indicated that there was amore » significant relationship between both tank level (p value of 1.65x10{sup -23}) and temperature (p value of 6.39x10{sup -6}) to the mercury vapor concentration in the tank ventilation system. Tank temperature showed the most promise as a controllable parameter for future tank cleaning endeavors. Despite statistically significant relationships, there may not be confidence in the ability to control accident scenarios to below mercury’s IDLH or PAC-III levels for future cleaning initiatives.« less

Marginal regression approach for additive hazards models with clustered current status data.

PubMed

Su, Pei-Fang; Chi, Yunchan

2014-01-15

Current status data arise naturally from tumorigenicity experiments, epidemiology studies, biomedicine, econometrics and demographic and sociology studies. Moreover, clustered current status data may occur with animals from the same litter in tumorigenicity experiments or with subjects from the same family in epidemiology studies. Because the only information extracted from current status data is whether the survival times are before or after the monitoring or censoring times, the nonparametric maximum likelihood estimator of survival function converges at a rate of n(1/3) to a complicated limiting distribution. Hence, semiparametric regression models such as the additive hazards model have been extended for independent current status data to derive the test statistics, whose distributions converge at a rate of n(1/2) , for testing the regression parameters. However, a straightforward application of these statistical methods to clustered current status data is not appropriate because intracluster correlation needs to be taken into account. Therefore, this paper proposes two estimating functions for estimating the parameters in the additive hazards model for clustered current status data. The comparative results from simulation studies are presented, and the application of the proposed estimating functions to one real data set is illustrated. Copyright © 2013 John Wiley & Sons, Ltd.

Risk of schizophrenia and minority status: a comparison of the Swedish-speaking minority and the Finnish-speaking majority in Finland

PubMed Central

Suvisaari, Jaana; Opler, Mark; Lindbohm, Marja-Liisa; Sallmén, Markku

2014-01-01

Approximately five percent of the Finnish population are Swedish-speaking and have higher socioeconomic position and longer life expectancy than the Finnish-speaking majority. Previous studies have not investigated whether Swedish-speaking Finns have lower risk of schizophrenia spectrum disorders (SSD) than Finnish-speaking Finns. We investigated this in a representative sample of 47 445 Finns born in 1972–1984. Hazard ratios of SSD between language groups were assessed with conditional proportional hazards regression. Sex, parental ages at birth, paternal employment around conception, parental psychosis and place and residence in the capital area were used as other explanatory variables. The prevalence of SSD was 0.7% in the Swedish-speaking minority and 1.5% in the Finnish-speaking majority. In the adjusted regression model, belonging to the Swedish-speaking minority was associated with lower risk of SSD (hazard ratio (HR) 0.41, 95% confidence interval (CI) 0.24–0.69). In a subset analysis by gender, the protective effect was evident among Swedish-speaking males (HR 0.32, 95% CI 0.15–0.68) but marginal in females (HR 0.75, 95% CI 0.41–1.37). Parental psychosis and place of birth in the capital area were associated with higher risk of SSD, whereas paternal employment at the time of conception was associated with lower risk of SSD. Our results support the role of social factors in the etiology of schizophrenia. Belonging to a minority with high socioeconomic status and social capital may be protective against schizophrenia, especially for males. PMID:25263996

Appendectomy correlates with increased risk of pyogenic liver abscess

PubMed Central

Liao, Kuan-Fu; Lai, Shih-Wei; Lin, Cheng-Li; Chien, Sou-Hsin

2016-01-01

Abstract Little is known on the association between appendectomy and pyogenic liver abscess. The objective of this study was to investigate the association between appendectomy and the risk of pyogenic liver abscess in Taiwan. This population-based retrospective cohort study was conducted using the hospitalization dataset of the Taiwan National Health Insurance Program. There were 212,530 subjects age 20 to 84 years with newly diagnosed appendectomy as the appendectomy group since 1998 to 2010, and 850,099 randomly selected subjects without appendectomy as the nonappendectomy group. Both appendectomy and nonappendectomy groups were matched with sex, age, comorbidities, and index year of diagnosing appendectomy. The incidence of pyogenic liver abscess at the end of 2011 was estimated in both groups. The multivariable Cox proportional hazards regression model was applied to investigate the hazard ratio (HR) and 95% confidence interval (CI) for risk of pyogenic liver abscess associated with appendectomy and other comorbidities including alcoholism, biliary stone, chronic kidney disease, chronic liver diseases, and diabetes mellitus. The overall incidence of pyogenic liver abscess was 1.73-fold greater in the appendectomy group than that in the nonappendectomy group (3.85 vs 2.22 per 10,000 person-years, 95% CI 1.71, 1.76). The multivariable regression analysis disclosed that the adjusted HR of pyogenic liver abscess was 1.77 for the appendectomy group (95% CI 1.59, 1.97), when compared with the nonappendectomy group. Appendectomy is associated with increased hazard of pyogenic liver abscess. Further studies remain necessary to confirm our findings. PMID:27368018

Comparison of the Risk of Gastrointestinal Bleeding among Different Statin Exposures with Concomitant Administration of Warfarin: Electronic Health Record-Based Retrospective Cohort Study.

PubMed

Shin, Dahye; Yoon, Dukyong; Lim, Sun Gyo; Hong, Ji Man; Park, Rae Woong; Lee, Jin Soo

2016-01-01

Patients who should be treated with both warfarin and a statin are frequently seen in vascular clinics. The risk for bleeding and potential drug interactions should be considered when prescribing both medications together. This study aimed to compare the risk for gastrointestinal bleeding among different statin exposures with concomitant administration of warfarin. This is a single-hospital retrospective cohort study. We included patients who were concomitantly exposed to one of four statins (pravastatin, simvastatin, atorvastatin, and rosuvastatin) and warfarin for up to 2 years (730 days). The observation period ended when a gastrointestinal bleeding event occurred or the observation was censored. Within-class comparisons were used, and 1:1 matching using a propensity score was performed for comparisons between each statin and all of the other statins. Kaplan-Meier analyses with log-rank tests and Cox proportional hazard regression analyses were conducted to determine associations with the risk of gastrointestinal bleeding. Data were analyzed for 1,686 patients who were concomitantly administered a statin and warfarin. Log-rank tests for the gastrointestinal bleeding-free survival rate showed that the risk for gastrointestinal bleeding was significantly lower in the pravastatin group (p = 0.0499) and higher in the rosuvastatin group (p = 0.009). In the Cox proportional hazard regression analysis, the hazard ratio of 5.394 for gastrointestinal bleeding based on statin exposure in the rosuvastatin group was significant (95% confidence interval, 1.168-24.916). There was a relatively high risk of gastrointestinal bleeding with rosuvastatin when administered concomitantly with warfarin.

Somatoform disorder as a predictor of interstitial cystitis/bladder pain syndrome: Evidence from a nested case-control study and a retrospective cohort study.

PubMed

Chen, I-Chun; Lee, Ming-Huei; Lin, Hsuan-Hung; Wu, Shang-Liang; Chang, Kun-Min; Lin, Hsiu-Ying

2017-05-01

Interstitial cystitis/bladder pain syndrome (IC/BPS) has several well-known comorbid psychiatric manifestations, including insomnia, anxiety, and depression. We hypothesized that somatoform disorder, which is a psychosomatic disease, can be used as a sensitive psychiatric phenotype of IC/BPS. We investigated whether somatoform disorder increases the risk of IC/BPS.A nested case-control study and a retrospective cohort study were followed up over a 12-year period (2002-2013) in the Taiwan Health Insurance Reimbursement Database. In the nested case-control study, 1612 patients with IC/BPS were matched in a 1:2 ratio to 3224 controls based on propensity scores. The odds ratio for somatoform disorder was calculated using conditional logistic regression analysis. In the retrospective cohort study, 1436 patients with somatoform disorder were matched in a 1:2 ratio to 2872 patients with nonsomatoform disorder based on propensity scores. Cox regression analysis was used to estimate the hazard ratio associated with the development of IC/BPS in patients with somatoform disorder, and the cumulative survival probability was tested using the Kaplan-Meier analysis.We found that the odds ratio for somatoform disorder was 2.46 (95% confidence interval [CI], 1.05-5.76). Although the average time until IC/BPS development in the control subjects was 11.5 ± 1.3 years, this interval was shorter in patients with somatoform disorder (6.3 ± 3.6 years). The hazard ratio for developing IC/BPS was 2.50 (95% CI 1.23-5.58); the adjusted hazard ratio was 2.26 (95% CI 1.002-5.007). The patients and controls also differed significantly in their cumulative survival probability for IC/BPS (log rank P < .05).Evidence from the nested case-control study and retrospective cohort study consistently indicated that somatoform disorder increases the risk for IC/BPS. Our study suggests that somatoform disorder can be used as a sensitive psychiatric phenotype to predict IC/BPS. Any past history of somatoform disorder should be documented while examining patients with IC/BPS.

Measuring moral hazard and adverse selection by propensity scoring in the mixed health care economy of Hong Kong.

PubMed

Wong, Irene O L; Lindner, Michael J; Cowling, Benjamin J; Lau, Eric H Y; Lo, Su-Vui; Leung, Gabriel M

2010-04-01

To evaluate the presence of moral hazard, adjusted for the propensity to have self-purchased insurance policies, employer-based medical benefits, and welfare-associated medical benefits in Hong Kong. Based on 2005 population survey, we used logistic regression and zero-truncated negative binomial/Poisson regressions to assess the presence of moral hazard by comparing inpatient and outpatient utilization between insured and uninsured individuals. We fitted each enabling factor specific to the type of service covered, and adjusted for predisposing socioeconomic and demographic factors. We used a propensity score approach to account for potential adverse selection. Employment-based benefits coverage was associated with increased access and intensity of use for both inpatient and outpatient care, except for public hospital use. Similarly, welfare-based coverage had comparable effect sizes as employment-based schemes, except for the total number of public ambulatory episodes. Self-purchased insurance facilitated access but did not apparently induce greater demand of services among ever users. Nevertheless, there was no evidence of moral hazard in public hospital use. Our findings suggest that employment-based benefits coverage lead to the greatest degree of moral hazard in Hong Kong. Future studies should focus on confirming these observational findings using a randomized design. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Assessing the prediction accuracy of a cure model for censored survival data with long-term survivors: Application to breast cancer data.

PubMed

Asano, Junichi; Hirakawa, Akihiro

2017-01-01

The Cox proportional hazards cure model is a survival model incorporating a cure rate with the assumption that the population contains both uncured and cured individuals. It contains a logistic regression for the cure rate, and a Cox regression to estimate the hazard for uncured patients. A single predictive model for both the cure and hazard can be developed by using a cure model that simultaneously predicts the cure rate and hazards for uncured patients; however, model selection is a challenge because of the lack of a measure for quantifying the predictive accuracy of a cure model. Recently, we developed an area under the receiver operating characteristic curve (AUC) for determining the cure rate in a cure model (Asano et al., 2014), but the hazards measure for uncured patients was not resolved. In this article, we propose novel C-statistics that are weighted by the patients' cure status (i.e., cured, uncured, or censored cases) for the cure model. The operating characteristics of the proposed C-statistics and their confidence interval were examined by simulation analyses. We also illustrate methods for predictive model selection and for further interpretation of variables using the proposed AUCs and C-statistics via application to breast cancer data.

Interest in using mobile technology to help self-manage alcohol use among persons living with HIV: A Florida Cohort cross-sectional study

PubMed Central

Sharpe, J. Danielle; Zhou, Zhi; Escobar-Viera, César G.; Morano, Jamie P.; Lucero, Robert J.; Ibañez, Gladys E.; Hart, Mark; Cook, Christa L.; Cook, Robert L.

2017-01-01

Background Alcohol consumption at hazardous levels is more prevalent and associated with poor health outcomes among persons living with HIV (PLWH). Although PLWH are receptive to using technology to manage health issues, it is unknown whether a cell phone app to self-manage alcohol use would be acceptable among PLWH who drink. The objectives of this study were to determine factors associated with interest in an app to self-manage drinking and to identify differences in baseline mobile technology use among PLWH by drinking level. Methods Our study population included 757 PLWH recruited from 2014–2016 into the Florida Cohort, an ongoing cohort study investigating the utilization of health services and HIV care outcomes among PLWH. Participants completed a questionnaire examining demographics, substance use, mobile technology use, and other health behaviors. We used multivariable logistic regression to identify factors significantly associated with interest in an app to self-manage drinking. We also determined whether mobile technology use varied by drinking level. Results Of the sample, 40% of persons who drink at hazardous levels, 34% of persons who drink at non-hazardous levels, and 19% of persons who do not drink were interested in a self-management app for alcohol use. Multivariable logistic regression analysis indicated that non-hazardous drinking (AOR 1.78; CI: 1.10–2.88) and hazardous drinking (AOR 2.58; CI: 1.60–4.16) were associated with interest, controlling for age, gender, education, and drug use. Regarding mobile technology use, most of the sample reported smartphone ownership (56%), text messaging (89%), and at least one cell phone app (69%). Conclusions Regardless of drinking level, overall mobile technology use among PLWH was moderate, while PLWH who consumed alcohol expressed greater interest in a cell phone app to self-manage alcohol use. This indicates that many PLWH who drink would be interested in and prepared for a mobile technology-based intervention to reduce alcohol consumption. PMID:28723300

Estimating hazard ratios in cohort data with missing disease information due to death.

PubMed

Binder, Nadine; Herrnböck, Anne-Sophie; Schumacher, Martin

2017-03-01

In clinical and epidemiological studies information on the primary outcome of interest, that is, the disease status, is usually collected at a limited number of follow-up visits. The disease status can often only be retrieved retrospectively in individuals who are alive at follow-up, but will be missing for those who died before. Right-censoring the death cases at the last visit (ad-hoc analysis) yields biased hazard ratio estimates of a potential risk factor, and the bias can be substantial and occur in either direction. In this work, we investigate three different approaches that use the same likelihood contributions derived from an illness-death multistate model in order to more adequately estimate the hazard ratio by including the death cases into the analysis: a parametric approach, a penalized likelihood approach, and an imputation-based approach. We investigate to which extent these approaches allow for an unbiased regression analysis by evaluating their performance in simulation studies and on a real data example. In doing so, we use the full cohort with complete illness-death data as reference and artificially induce missing information due to death by setting discrete follow-up visits. Compared to an ad-hoc analysis, all considered approaches provide less biased or even unbiased results, depending on the situation studied. In the real data example, the parametric approach is seen to be too restrictive, whereas the imputation-based approach could almost reconstruct the original event history information. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Short sleep duration is associated with B-type natriuretic peptide levels and predicts the death of Japanese patients with type 2 diabetes.

PubMed

Hamasaki, Hidetaka; Katsuyama, Hisayuki; Sako, Akahito; Yanai, Hidekatsu

2017-08-01

To investigate the associations of sleep duration with all-cause mortality, glycemic control, and other clinical parameters of patients with type 2 diabetes. From April 2013 to December 2015, we conducted a retrospective cohort study. Study participants were divided into three groups according to their sleep duration. Multiple regression analysis and Cox proportional hazards analysis were performed to assess the independent associations of sleep duration with clinical parameters and all-cause mortality. We enrolled 1233 patients who were then followed for 860 ± 264 days. During the follow-up period, 20 patients (1.6%) died. Sleep duration inversely associated with plasma B-type natriuretic peptide levels (β = -0.203, p = 0.012) in short (<7 h) sleepers, whereas it was positively associated with hemoglobin A1c levels (β = 0.156, p = 0.021) in long (≥9 h) sleepers. Moreover, Cox proportional hazard analysis revealed that short sleep duration was a significant predictor of all-cause mortality (hazard ratio = 0.473; confidence interval 0.248-0.905, p = 0.024). Short sleep duration may serve as a prognostic indicator of mortality in Japanese patients with type 2 diabetes and may increase cardiovascular stress. Adequate sleep is essential for the management of type 2 diabetes. Copyright © 2017 Elsevier B.V. All rights reserved.

Psychosocial Hazard Analysis in a Heterogeneous Workforce: Determinants of Work Stress in Blue- and White-Collar Workers of the European Steel Industry.

PubMed

Metzler, Yannick Arnold; Bellingrath, Silja

2017-01-01

The European steel industry's workforce is highly heterogeneous and consists of various occupational groups, presumably facing different psychosocial stressors. The few existing studies on the subject mainly focused on physical constraints of blue-collar workers, whereas the supposable psychosocial workload received only little research attention. This is remarkable considering the challenges associated with statutory required risk assessment of psychosocial hazards. Valid measures of hazard analysis must account for various stressors and reliably identify them, also between occupational groups. The present study, based on a sample of blue- and white-collar workers ( N  = 124) from the European steel industry, aims to provide a first insight into psychosocial stressors and strain at work in this rarely researched industrial sector. Furthermore, two well-known theoretical roadmaps in job analysis are examined regarding their utility for risk assessment in heterogeneous workforces: the German standard version of the Copenhagen Psychosocial Questionnaire (COPSOQ) and the short version of the effort-reward imbalance questionnaire. Hierarchical multiple regression analyses revealed that the COPSOQ was better suited to predict various strain indices in the present sample. Especially stressors relating to socioemotional aspects, such as work-privacy conflict, revealed a reasonable impact, indicating the need for comprehensive solutions at the organizational level instead of solutions focusing on single workplaces. To conclude, a broadly diversified and validated approach in psychosocial risk assessment is needed to adequately assess the variety of psychosocial factors at work and in different occupational groups.

Lean body mass predicts long-term survival in Chinese patients on peritoneal dialysis.

PubMed

Huang, Jenq-Wen; Lien, Yu-Chung; Wu, Hon-Yen; Yen, Chung-Jen; Pan, Chun-Chun; Hung, Tsai-Wei; Su, Chi-Ting; Chiang, Chih-Kang; Cheng, Hui-Teng; Hung, Kuan-Yu

2013-01-01

Reduced lean body mass (LBM) is one of the main indicators in malnutrition inflammation syndrome among patients on dialysis. However, the influence of LBM on peritoneal dialysis (PD) patients' outcomes and the factors related to increasing LBM are seldom reported. We enrolled 103 incident PD patients between 2002 and 2003, and followed them until December 2011. Clinical characteristics, PD-associated parameters, residual renal function, and serum chemistry profiles of each patient were collected at 1 month and 1 year after initiating PD. LBM was estimated using creatinine index corrected with body weight. Multiple linear regression analysis, Kaplan-Meier survival analysis, and Cox regression proportional hazard analysis were used to define independent variables and compare survival between groups. Using the median LBM value (70% for men and 64% for women), patients were divided into group 1 (n = 52; low LBM) and group 2 (n = 51; high LBM). Group 1 patients had higher rates of peritonitis (1.6 vs. 1.1/100 patient months; p<0.05) and hospitalization (14.6 vs. 9.7/100 patient months; p<0.05). Group 1 patients also had shorter overall survival and technique survival (p<0.01). Each percentage point increase in LBM reduced the hazard ratio for mortality by 8% after adjustment for diabetes, age, sex, and body mass index (BMI). Changes in residual renal function and protein catabolic rate were independently associated with changes in LBM in the first year of PD. LBM serves as a good parameter in addition to BMI to predict the survival of patients on PD. Preserving residual renal function and increasing protein intake can increase LBM.

Lean Body Mass Predicts Long-Term Survival in Chinese Patients on Peritoneal Dialysis

PubMed Central

Huang, Jenq-Wen; Lien, Yu-Chung; Wu, Hon-Yen; Yen, Chung-Jen; Pan, Chun-Chun; Hung, Tsai-Wei; Su, Chi-Ting; Chiang, Chih-Kang; Cheng, Hui-Teng; Hung, Kuan-Yu

2013-01-01

Background Reduced lean body mass (LBM) is one of the main indicators in malnutrition inflammation syndrome among patients on dialysis. However, the influence of LBM on peritoneal dialysis (PD) patients’ outcomes and the factors related to increasing LBM are seldom reported. Methods We enrolled 103 incident PD patients between 2002 and 2003, and followed them until December 2011. Clinical characteristics, PD-associated parameters, residual renal function, and serum chemistry profiles of each patient were collected at 1 month and 1 year after initiating PD. LBM was estimated using creatinine index corrected with body weight. Multiple linear regression analysis, Kaplan–Meier survival analysis, and Cox regression proportional hazard analysis were used to define independent variables and compare survival between groups. Results Using the median LBM value (70% for men and 64% for women), patients were divided into group 1 (n = 52; low LBM) and group 2 (n = 51; high LBM). Group 1 patients had higher rates of peritonitis (1.6 vs. 1.1/100 patient months; p<0.05) and hospitalization (14.6 vs. 9.7/100 patient months; p<0.05). Group 1 patients also had shorter overall survival and technique survival (p<0.01). Each percentage point increase in LBM reduced the hazard ratio for mortality by 8% after adjustment for diabetes, age, sex, and body mass index (BMI). Changes in residual renal function and protein catabolic rate were independently associated with changes in LBM in the first year of PD. Conclusions LBM serves as a good parameter in addition to BMI to predict the survival of patients on PD. Preserving residual renal function and increasing protein intake can increase LBM. PMID:23372806

Carbapenem-resistant Enterobacteriaceae colonization and infection in critically ill patients: a retrospective matched cohort comparison with non-carriers.

PubMed

Dickstein, Y; Edelman, R; Dror, T; Hussein, K; Bar-Lavie, Y; Paul, M

2016-09-01

To examine whether carbapenem-resistant Enterobacteriaceae (CRE) carriage is associated with incidence of clinical infection as a means of assessing whether the morbidity and mortality associated with these bacteria are mediated by underlying conditions or intrinsic properties of CRE. This retrospective matched cohort study compared the incidence of invasive infections in CRE-colonized patients and matched non-carriers in the intensive care unit (ICU). The primary outcome was infection caused by CRE of the same species as the colonizing strain among CRE carriers, and infections caused by carbapenem-sensitive strains of the same organism in non-carriers. Hospital discharge and death were considered as competing events. Competing-risks hazard analysis was performed for the entire cohort and for a nested cohort matched by Acute Physiology and Chronic Health Evaluation (APACHE) II scores, stratified by matching. In total, 146 CRE carriers were compared with 292 non-carriers. Patients were well matched for most risk factors for Enterobacteriaceae infection, including age, renal failure, previous invasive infection, previous hospitalization, APACHE II score, length of mechanical ventilation, length of hospitalization and CRE carriage. On regression analysis, colonization with CRE was independently associated with Enterobacteriaceae infection {cause-specific hazard ratio (CSHR) 2.06 [95% confidence interval (CI) 1.03-4.09]}. On regression analysis of the APACHE-II-matched cohort (N=284), colonization with CRE remained significantly associated with Enterobacteriaceae infection [CSHR 3.32 (95% CI 1.31-8.43)]. Colonization with CRE was associated with at least a two-fold increased risk of infection by the colonizing strain amongst ICU patients. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Calorie intake and patient outcomes in severe acute kidney injury: findings from The Randomized Evaluation of Normal vs. Augmented Level of Replacement Therapy (RENAL) study trial

PubMed Central

2014-01-01

Introduction Current practice in the delivery of caloric intake (DCI) in patients with severe acute kidney injury (AKI) receiving renal replacement therapy (RRT) is unknown. We aimed to describe calorie administration in patients enrolled in the Randomized Evaluation of Normal vs. Augmented Level of Replacement Therapy (RENAL) study and to assess the association between DCI and clinical outcomes. Methods We performed a secondary analysis in 1456 patients from the RENAL trial. We measured the dose and evolution of DCI during treatment and analyzed its association with major clinical outcomes using multivariable logistic regression, Cox proportional hazards models, and time adjusted models. Results Overall, mean DCI during treatment in ICU was low at only 10.9 ± 9 Kcal/kg/day for non-survivors and 11 ± 9 Kcal/kg/day for survivors. Among patients with a lower DCI (below the median) 334 of 729 (45.8%) had died at 90-days after randomization compared with 316 of 727 (43.3%) patients with a higher DCI (above the median) (P = 0.34). On multivariable logistic regression analysis, mean DCI carried an odds ratio of 0.95 (95% confidence interval (CI): 0.91-1.00; P = 0.06) per 100 Kcal increase for 90-day mortality. DCI was not associated with significant differences in renal replacement (RRT) free days, mechanical ventilation free days, ICU free days and hospital free days. These findings remained essentially unaltered after time adjusted analysis and Cox proportional hazards modeling. Conclusions In the RENAL study, mean DCI was low. Within the limits of such low caloric intake, greater DCI was not associated with improved clinical outcomes. Trial registration ClinicalTrials.gov number, NCT00221013 PMID:24629036

Prediction of non-biochemical recurrence rate after radical prostatectomy in a Japanese cohort: development of a postoperative nomogram.

PubMed

Okubo, Hidenori; Ohori, Makoto; Ohno, Yoshio; Nakashima, Jun; Inoue, Rie; Nagao, Toshitaka; Tachibana, Masaaki

2014-05-01

To develop a nomogram based on postoperative factors and prostate-specific antigen levels to predict the non-biochemical recurrence rate after radical prostatectomy ina Japanese cohort. A total of 606 Japanese patients with T1-3N0M0 prostate cancer who underwent radical prostatectomy and pelvic lymph node dissection at Tokyo Medical University hospital from 2000 to 2010 were studied. A nomogram was constructed based on Cox hazard regression analysis evaluating the prognostic significance of serum prostate-specific antigen and pathological factors in the radical prostatectomy specimens. The discriminating ability of the nomogram was assessed by the concordance index (C-index), and the predicted and actual outcomes were compared with a bootstrapped calibration plot. With a mean follow up of 60.0 months, a total of 187 patients (30.9%) experienced biochemical recurrence, with a 5-year non-biochemical recurrence rate of 72.3%. Based on a Cox hazard regression model, a nomogram was constructed to predict non-biochemical recurrence using serum prostate-specific antigen level and pathological features in radical prostatectomy specimens. The concordance index was 0.77, and the calibration plots appeared to be accurate. The postoperative nomogram described here can provide valuable information regarding the need for adjuvant/salvage radiation or hormonal therapy in patients after radical prostatectomy.

Trends in the incidence of dementia: design and methods in the Alzheimer Cohorts Consortium.

PubMed

Chibnik, Lori B; Wolters, Frank J; Bäckman, Kristoffer; Beiser, Alexa; Berr, Claudine; Bis, Joshua C; Boerwinkle, Eric; Bos, Daniel; Brayne, Carol; Dartigues, Jean-Francois; Darweesh, Sirwan K L; Debette, Stephanie; Davis-Plourde, Kendra L; Dufouil, Carole; Fornage, Myriam; Grasset, Leslie; Gudnason, Vilmundur; Hadjichrysanthou, Christoforos; Helmer, Catherine; Ikram, M Arfan; Ikram, M Kamran; Kern, Silke; Kuller, Lewis H; Launer, Lenore; Lopez, Oscar L; Matthews, Fiona; Meirelles, Osorio; Mosley, Thomas; Ower, Alison; Psaty, Bruce M; Satizabal, Claudia L; Seshadri, Sudha; Skoog, Ingmar; Stephan, Blossom C M; Tzourio, Christophe; Waziry, Reem; Wong, Mei Mei; Zettergren, Anna; Hofman, Albert

2017-10-01

Several studies have reported a decline in incidence of dementia which may have large implications for the projected burden of disease, and provide important guidance to preventive efforts. However, reports are conflicting or inconclusive with regard to the impact of gender and education with underlying causes of a presumed declining trend remaining largely unidentified. The Alzheimer Cohorts Consortium aggregates data from nine international population-based cohorts to determine changes in the incidence of dementia since 1990. We will employ Poisson regression models to calculate incidence rates in each cohort and Cox proportional hazard regression to compare 5-year cumulative hazards across study-specific epochs. Finally, we will meta-analyse changes per decade across cohorts, and repeat all analysis stratified by sex, education and APOE genotype. In all cohorts combined, there are data on almost 69,000 people at risk of dementia with the range of follow-up years between 2 and 27. The average age at baseline is similar across cohorts ranging between 72 and 77. Uniting a wide range of disease-specific and methodological expertise in research teams, the first analyses within the Alzheimer Cohorts Consortium are underway to tackle outstanding challenges in the assessment of time-trends in dementia occurrence.

Southern Dietary Pattern is Associated With Hazard of Acute Coronary Heart Disease in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study.

PubMed

Shikany, James M; Safford, Monika M; Newby, P K; Durant, Raegan W; Brown, Todd M; Judd, Suzanne E

2015-09-01

The association of overall diet, as characterized by dietary patterns, with risk of incident acute coronary heart disease (CHD) has not been studied extensively in samples including sociodemographic and regional diversity. We used data from 17 418 participants in Reasons for Geographic and Racial Differences in Stroke (REGARDS), a national, population-based, longitudinal study of white and black adults aged ≥45 years, enrolled from 2003 to 2007. We derived dietary patterns with factor analysis and used Cox proportional hazards regression to examine hazard of incident acute CHD events - nonfatal myocardial infarction and acute CHD death - associated with quartiles of consumption of each pattern, adjusted for various levels of covariates. Five primary dietary patterns emerged: Convenience, Plant-based, Sweets, Southern, and Alcohol and Salad. A total of 536 acute CHD events occurred over a median (interquartile range) 5.8 (2.1) years of follow-up. After adjustment for sociodemographics, lifestyle factors, and energy intake, highest consumers of the Southern pattern (characterized by added fats, fried food, eggs, organ and processed meats, and sugar-sweetened beverages) experienced a 56% higher hazard of acute CHD (comparing quartile 4 with quartile 1: hazard ratio, 1.56; 95% confidence interval, 1.17-2.08; P for trend across quartiles=0.003). Adding anthropometric and medical history variables to the model attenuated the association somewhat (hazard ratio, 1.37; 95% confidence interval, 1.01-1.85; P=0.036). A dietary pattern characteristic of the southern United States was associated with greater hazard of CHD in this sample of white and black adults in diverse regions of the United States. © 2015 American Heart Association, Inc.

NASA Hazard Analysis Process

NASA Technical Reports Server (NTRS)

Deckert, George

2010-01-01

This viewgraph presentation reviews The NASA Hazard Analysis process. The contents include: 1) Significant Incidents and Close Calls in Human Spaceflight; 2) Subsystem Safety Engineering Through the Project Life Cycle; 3) The Risk Informed Design Process; 4) Types of NASA Hazard Analysis; 5) Preliminary Hazard Analysis (PHA); 6) Hazard Analysis Process; 7) Identify Hazardous Conditions; 8) Consider All Interfaces; 9) Work a Preliminary Hazard List; 10) NASA Generic Hazards List; and 11) Final Thoughts

Accounting for individual differences and timing of events: estimating the effect of treatment on criminal convictions in heroin users.

PubMed

Røislien, Jo; Clausen, Thomas; Gran, Jon Michael; Bukten, Anne

2014-05-17

The reduction of crime is an important outcome of opioid maintenance treatment (OMT). Criminal intensity and treatment regimes vary among OMT patients, but this is rarely adjusted for in statistical analyses, which tend to focus on cohort incidence rates and rate ratios. The purpose of this work was to estimate the relationship between treatment and criminal convictions among OMT patients, adjusting for individual covariate information and timing of events, fitting time-to-event regression models of increasing complexity. National criminal records were cross linked with treatment data on 3221 patients starting OMT in Norway 1997-2003. In addition to calculating cohort incidence rates, criminal convictions was modelled as a recurrent event dependent variable, and treatment a time-dependent covariate, in Cox proportional hazards, Aalen's additive hazards, and semi-parametric additive hazards regression models. Both fixed and dynamic covariates were included. During OMT, the number of days with criminal convictions for the cohort as a whole was 61% lower than when not in treatment. OMT was associated with reduced number of days with criminal convictions in all time-to-event regression models, but the hazard ratio (95% CI) was strongly attenuated when adjusting for covariates; from 0.40 (0.35, 0.45) in a univariate model to 0.79 (0.72, 0.87) in a fully adjusted model. The hazard was lower for females and decreasing with older age, while increasing with high numbers of criminal convictions prior to application to OMT (all p < 0.001). The strongest predictors were level of criminal activity prior to entering into OMT, and having a recent criminal conviction (both p < 0.001). The effect of several predictors was significantly time-varying with their effects diminishing over time. Analyzing complex observational data regarding to fixed factors only overlooks important temporal information, and naïve cohort level incidence rates might result in biased estimates of the effect of interventions. Applying time-to-event regression models, properly adjusting for individual covariate information and timing of various events, allows for more precise and reliable effect estimates, as well as painting a more nuanced picture that can aid health care professionals and policy makers.

Estrogen receptor (α and β) but not androgen receptor expression is correlated with recurrence, progression and survival in post prostatectomy T3N0M0 locally advanced prostate cancer in an urban Greek population

PubMed Central

Megas, Georgios; Chrisofos, Michael; Anastasiou, Ioannis; Tsitlidou, Aida; Choreftaki, Theodosia; Deliveliotis, Charalampos

2015-01-01

The objective of this study was to evaluate the expression of estrogen receptors (ER(α) and ER(β)) and androgen receptors (ARs) as prognostic factors for biochemical recurrence, disease progression and survival in patients with pT3N0M0 prostate cancer (PCa) in an urban Greek population. A total of 100 consecutive patients with pT3N0M0 PCa treated with radical prostatectomy participated in the study. The mean age and follow-up were 64.2 and 6 years, respectively. The HSCORE was used for semi-quantitative analysis of the immunoreactivity of the receptors. The prognostic value of the ER(α) and ER(β) and AR was assessed in terms of recurrence, progression, and survival. AR expression was not associated with any of the above parameters; however, both ERs correlated with the prognosis. A univariate Cox regression analysis showed that ER(α) positive staining was significantly associated with a greater hazard for all outcomes. Increased ER(β) staining was significantly associated with a lower hazard for all outcomes in the univariate analysis. When both ER HSCORES were used for the analysis, it was found that patients with high ER(α) or low ER(β) HSCORES compared with patients with negatively stained ER(α) and >1.7 hSCORE ER(β) had 6.03, 10.93, and 10.53 times greater hazard for biochemical disease recurrence, progression of disease and death, respectively. Multiple Cox proportional hazard analyses showed that the age, preoperative prostate specific antigen, Gleason score and ERs were independent predictors of all outcomes. ER expression is an important prognosticator after radical prostatectomy in patients with pT3N0M0 PCa. By contrast, AR expression has limited prognostic value. PMID:25219910

Estrogen receptor (α and β) but not androgen receptor expression is correlated with recurrence, progression and survival in post prostatectomy T3N0M0 locally advanced prostate cancer in an urban Greek population.

PubMed

Megas, Georgios; Chrisofos, Michael; Anastasiou, Ioannis; Tsitlidou, Aida; Choreftaki, Theodosia; Deliveliotis, Charalampos

2015-01-01

The objective of this study was to evaluate the expression of estrogen receptors (ER(α) and ER(β)) and androgen receptors (ARs) as prognostic factors for biochemical recurrence, disease progression and survival in patients with pT3N0M0 prostate cancer (PCa) in an urban Greek population. A total of 100 consecutive patients with pT3N0M0 PCa treated with radical prostatectomy participated in the study. The mean age and follow-up were 64.2 and 6 years, respectively. The HSCORE was used for semi-quantitative analysis of the immunoreactivity of the receptors. The prognostic value of the ER(α) and ER(β) and AR was assessed in terms of recurrence, progression, and survival. AR expression was not associated with any of the above parameters; however, both ERs correlated with the prognosis. A univariate Cox regression analysis showed that ER(α) positive staining was significantly associated with a greater hazard for all outcomes. Increased ER(β) staining was significantly associated with a lower hazard for all outcomes in the univariate analysis. When both ER HSCORES were used for the analysis, it was found that patients with high ER(α) or low ER(β) HSCORES compared with patients with negatively stained ER(α) and >1.7 hSCORE ER(β) had 6.03, 10.93, and 10.53 times greater hazard for biochemical disease recurrence, progression of disease and death, respectively. Multiple Cox proportional hazard analyses showed that the age, preoperative prostate specific antigen, Gleason score and ERs were independent predictors of all outcomes. ER expression is an important prognosticator after radical prostatectomy in patients with pT3N0M0 PCa. By contrast, AR expression has limited prognostic value.

Job Loss, Unemployment and the Incidence of Hazardous Drinking during the Late 2000s Recession in Europe among Adults Aged 50-64 Years.

PubMed

Bosque-Prous, Marina; Espelt, Albert; Sordo, Luis; Guitart, Anna M; Brugal, M Teresa; Bravo, Maria J

2015-01-01

To estimate the incidence of hazardous drinking in middle-aged people during an economic recession and ascertain whether individual job loss and contextual changes in unemployment influence the incidence rate in that period. Longitudinal study based on two waves of the SHARE project (Survey of Health, Ageing and Retirement in Europe). Individuals aged 50-64 years from 11 European countries, who were not hazardous drinkers at baseline (n = 7,615), were selected for this study. We estimated the cumulative incidence of hazardous drinking (≥40g and ≥20g of pure alcohol on average in men and women, respectively) between 2006 and 2012. Furthermore, in the statistical analysis, multilevel Poisson regression models with robust variance were fitted and obtained Risk Ratios (RR) and their 95% Confidence Intervals (95%CI). Over a 6-year period, 505 subjects became hazardous drinkers, with cumulative incidence of 6.6 per 100 persons between 2006 and 2012 (95%CI:6.1-7.2). Age [RR = 1.02 (95%CI:1.00-1.04)] and becoming unemployed [RR = 1.55 (95%CI:1.08-2.23)] were independently associated with higher risk of becoming a hazardous drinker. Conversely, having poorer self-perceived health was associated with lower risk of becoming a hazardous drinker [RR = 0.75 (95%CI:0.60-0.95)]. At country-level, an increase in the unemployment rate during the study period [RR = 1.32 (95%CI:1.17-1.50)] and greater increases in the household disposable income [RR = 0.97 (95%CI:0.95-0.99)] were associated with risk of becoming a hazardous drinker. Job loss among middle-aged individuals during the economic recession was positively associated with becoming a hazardous drinker. Changes in country-level variables were also related to this drinking pattern.

Prognostic factors in multiple myeloma: selection using Cox's proportional hazard model.

PubMed

Pasqualetti, P; Collacciani, A; Maccarone, C; Casale, R

1996-01-01

The pretreatment characteristics of 210 patients with multiple myeloma, observed between 1980 and 1994, were evaluated as potential prognostic factors for survival. Multivariate analysis according to Cox's proportional hazard model identified in the 160 dead patients with myeloma, among 26 different single prognostic variables, the following factors in order of importance: beta 2-microglobulin; bone marrow plasma cell percentage, hemoglobinemia, degree of lytic bone lesions, serum creatinine, and serum albumin. By analysis of these variables a prognostic index (PI), that considers the regression coefficients derived by Cox's model of all significant factors, was obtained. Using this it was possible to separate the whole patient group into three stages: stage I (PI < 1.485, 67 patients), stage II (PI: 1.485-2.090, 76 patients), and stage III (PI > 2.090, 67 patients), with a median survivals of 68, 36 and 13 months (P < 0.0001), respectively. Also the responses to therapy (P < 0.0001) and the survival curves (P < 0.00001) presented significant differences among the three subgroups. Knowledge of these factors could be of value in predicting prognosis and in planning therapy in patients with multiple myeloma.

Urate levels predict survival in amyotrophic lateral sclerosis: Analysis of the expanded Pooled Resource Open-Access ALS clinical trials database.

PubMed

Paganoni, Sabrina; Nicholson, Katharine; Chan, James; Shui, Amy; Schoenfeld, David; Sherman, Alexander; Berry, James; Cudkowicz, Merit; Atassi, Nazem

2018-03-01

Urate has been identified as a predictor of amyotrophic lateral sclerosis (ALS) survival in some but not all studies. Here we leverage the recent expansion of the Pooled Resource Open-Access ALS Clinical Trials (PRO-ACT) database to study the association between urate levels and ALS survival. Pooled data of 1,736 ALS participants from the PRO-ACT database were analyzed. Cox proportional hazards regression models were used to evaluate associations between urate levels at trial entry and survival. After adjustment for potential confounders (i.e., creatinine and body mass index), there was an 11% reduction in risk of reaching a survival endpoint during the study with each 1-mg/dL increase in uric acid levels (adjusted hazard ratio 0.89, 95% confidence interval 0.82-0.97, P < 0.01). Our pooled analysis provides further support for urate as a prognostic factor for survival in ALS and confirms the utility of the PRO-ACT database as a powerful resource for ALS epidemiological research. Muscle Nerve 57: 430-434, 2018. © 2017 Wiley Periodicals, Inc.

Sodium Valproate, a Histone Deacetylase Inhibitor, Is Associated With Reduced Stroke Risk After Previous Ischemic Stroke or Transient Ischemic Attack

PubMed Central

Brookes, Rebecca L.; Crichton, Siobhan; Wolfe, Charles D.A.; Yi, Qilong; Li, Linxin; Hankey, Graeme J.; Rothwell, Peter M.

2018-01-01

Background and Purpose— A variant in the histone deacetylase 9 (HDAC9) gene is associated with large artery stroke. Therefore, inhibiting HDAC9 might offer a novel secondary preventative treatment for ischemic stroke. The antiepileptic drug sodium valproate (SVA) is a nonspecific inhibitor of HDAC9. We tested whether SVA therapy given after ischemic stroke was associated with reduced recurrent stroke rate. Methods— Data were pooled from 3 prospective studies recruiting patients with previous stroke or transient ischemic attack and long-term follow-up: the South London Stroke Register, The Vitamins to Prevent Stroke Study, and the Oxford Vascular Study. Patients receiving SVA were compared with patients who received antiepileptic drugs other than SVA using survival analysis and Cox Regression. Results— A total of 11 949 patients with confirmed ischemic event were included. Recurrent stroke rate was lower in patient taking SVA (17 of 168) than other antiepileptic drugs (105 of 530; log-rank survival analysis P=0.002). On Cox regression, controlling for potential cofounders, SVA remained associated with reduced stroke (hazard ratio=0.44; 95% confidence interval: 0.3–0.7; P=0.002). A similar result was obtained when patients taking SVA were compared with all cases not taking SVA (Cox regression, hazard ratio=0.47; 95% confidence interval: 0.29–0.77; P=0.003). Conclusions— These results suggest that exposure to SVA, an inhibitor of HDAC, may be associated with a lower recurrent stroke risk although we cannot exclude residual confounding in this study design. This supports the hypothesis that HDAC9 is important in the ischemic stroke pathogenesis and that its inhibition, by SVA or a more specific HDAC9 inhibitor, is worthy of evaluation as a treatment to prevent recurrent ischemic stroke. PMID:29247141

Association of Radiation Dose to the Eyes With the Risk for Cataract After Nonretinoblastoma Solid Cancers in Childhood.

PubMed

Allodji, Rodrigue S; Diallo, Ibrahima; El-Fayech, Chiraz; Kahlouche, Amar; Dumas, Agnès; Schwartz, Boris; Oberlin, Odile; Benadjaoud, Mohamed Amine; Labbé, Martine; Jackson, Angela; Bullet, Julien; Rubino, Carole; Haddy, Nadia; De Vathaire, Florent

2016-04-01

Few studies have been published on the association of the radiation dose received to the eyes during radiotherapy (RT) for childhood cancer and the risk for later cataract. To investigate the risk for cataract after treatment of nonretinoblastoma solid cancer in childhood. The study used data from the Euro2K cohort that includes 4389 5-year survivors of solid tumors treated from January 1, 1945, to December 31, 1985; of these, 3172 patients were treated in France. A self-reported questionnaire was sent to French survivors from September 1, 2005, to December 31, 2012, when follow-up was considered completed for this study. However, 619 patients died before the beginning of the study and 128 patients treated for a retinoblastoma or who underwent enucleation were excluded. Likewise, 429 patients with unknown addresses or who did not return the consent form and 163 nonresponders did not participate. The remaining 1833 patients who completed the questionnaire underwent analysis for this study from June 1, 2014, to December 7, 2015. Radiation doses in both eyes for individuals were estimated for all patients who had received RT. The role of the radiation dose in cataract risk was investigated using the Cox proportional hazard regression model and the excess relative or the absolute risk model. The role of ctytotoxic chemotherapy was also investigated. The 1833 patients (961 men [52.4%]; 872 women [47.6%]; mean [SD] age, 37.0 [8.5]) who returned the questionnaire were included in the analysis. After a mean follow-up of 32 years, 33 patients with unilateral or bilateral cataract were identified, for a total of 47 cataract events. The 47 events were validated by medical record review and by contacting the patients and the corresponding medical physician or ophthalmologist to obtain copies of diagnostic examinations or surgical reports. Overall, in a multivariable Cox proportional hazard regression analysis, patients who received RT had a 4.4-fold (95% CI, 1.5- to 13.0-fold) increased risk for cataract compared with patients who did not receive RT. Exposure to radiation doses of at least 10 Gy to the eyes increased the hazard ratio 39-fold (95% CI, 12.0- to 127.9-fold), relative to no radiation exposure. Although based on few patients, a strong increase in cataract risk (hazard ratio, 26.3; 95% CI, 7.1-96.6) was observed in patients treated with melphalan hydrochloride. This study can inform guideline-based recommendations for long-term follow-up for cataract.

Does Workplace Social Capital Associate with Hazardous Drinking Among Chinese Rural-Urban Migrant Workers?

PubMed Central

Gao, Junling; Weaver, Scott R.; Fua, Hua; Pan, Zhigang

2014-01-01

Background The present study sought to investigate the associations between workplace social capital and hazardous drinking (HD) among Chinese rural-urban migrant workers (RUMW). Methods A cross sectional study with a multi-stage stratified sampling procedure was conducted in Shanghai during July 2012 to January 2013. In total, 5,318 RUMWs from 77 workplaces were involved. Work-place social capital was assessed using a validated and psychometrically tested eight-item measure. The Chinese version of Alcohol Use Disorders Identification Test (AUDIT) was used to assess hazardous drinking. Control variables included gender, age, marital status, education level, salary, and current smoking. Multilevel logistic regression analysis was conducted to test whether individual- and workplace-level social capital was associated with hazardous drinking. Results Overall, the prevalence of HD was 10.6%. After controlling for individual-level socio-demographic and lifestyle variables, compared to workers in the highest quartile of individual-level social capital, the odds of HD for workers in the three bottom quartiles were 1.13(95%CI: 1.04–1.23), 1.17(95%CI: 1.05–1.56) and 1.26(95%CI: 1.13–1.72), respectively. However, contrary to hypothesis, there was no relationship between workplace-level social capital and hazardous drinking. Conclusions Higher individual-level social capital may protect against HD among Chinese RUMWs. Interventions to build individual social capital among RUMWs in China may help reduce HD among this population. PMID:25502013

Cystic Fibrosis Associated with Worse Survival After Liver Transplantation.

PubMed

Black, Sylvester M; Woodley, Frederick W; Tumin, Dmitry; Mumtaz, Khalid; Whitson, Bryan A; Tobias, Joseph D; Hayes, Don

2016-04-01

Survival in cystic fibrosis patients after liver transplantation and liver-lung transplantation is not well studied. To discern survival rates after liver transplantation and liver-lung transplantation in patients with and without cystic fibrosis. The United Network for Organ Sharing database was queried from 1987 to 2013. Univariate Cox proportional hazards, multivariate Cox models, and propensity score matching were performed. Liver transplant and liver-lung transplant were performed in 212 and 53 patients with cystic fibrosis, respectively. Univariate Cox proportional hazards regression identified lower survival in cystic fibrosis after liver transplant compared to a reference non-cystic fibrosis liver transplant cohort (HR 1.248; 95 % CI 1.012, 1.541; p = 0.039). Supplementary analysis found graft survival was similar across the 3 recipient categories (log-rank test: χ(2) 2.68; p = 0.262). Multivariate Cox models identified increased mortality hazard among cystic fibrosis patients undergoing liver transplantation (HR 2.439; 95 % CI 1.709, 3.482; p < 0.001) and liver-lung transplantation (HR 2.753; 95 % CI 1.560, 4.861; p < 0.001). Propensity score matching of cystic fibrosis patients undergoing liver transplantation to non-cystic fibrosis controls identified a greater mortality hazard in the cystic fibrosis cohort using a Cox proportional hazards model stratified on matched pairs (HR 3.167; 95 % CI 1.265, 7.929, p = 0.014). Liver transplantation in cystic fibrosis is associated with poorer long-term patient survival compared to non-cystic fibrosis patients, although the difference is not due to graft survival.

Association of Time between Surgery and Adjuvant Therapy with Survival in Oral Cavity Cancer.

PubMed

Chen, Michelle M; Harris, Jeremy P; Orosco, Ryan K; Sirjani, Davud; Hara, Wendy; Divi, Vasu

2018-06-01

Objective The National Cancer Center Network recommends starting radiation therapy within 6 weeks after surgery for oral cavity squamous cell carcinoma (OCSCC), but there is limited evidence of the importance of the total time from surgery to completion of radiation therapy (package time). We set out to determine if there was an association between package time and survival in OCSCC and to evaluate the impact of treatment location on outcomes. Study Design Retrospective cohort study. Setting Tertiary academic medical center. Subjects and Methods We reviewed the records of patients with OCSCC who completed postoperative radiation therapy at an academic medical center from 2008 to 2016. The primary endpoints were overall survival and recurrence-free survival. Statistical analysis included χ 2 tests and Cox proportional hazards regressions. Results We identified 132 patients with an average package time of 12.6 weeks. On multivariate analysis, package time >11 weeks was independently associated with decreased overall survival (hazard ratio, 6.68; 95% CI, 1.42-31.44) and recurrence-free survival (hazard ratio, 2.94; 95% CI, 1.20-7.18). Patients who received radiation therapy at outside facilities were more likely to have treatment delays (90.2% vs 62.9%, P = .001). Conclusions Prolonged package times are associated with decreased overall and recurrence-free survival among patients with OCSCC. Patients who received radiation therapy at outside facilities are more likely to have prolonged package times.

[Establishment of the prediction model for ischemic cardiovascular disease of elderly male population under current health care program].

PubMed

Chen, Jin-hong; Wu, Hai-yun; He, Kun-lun; He, Yao; Qin, Yin-he

2010-10-01

To establish and verify the prediction model for ischemic cardiovascular disease (ICVD) among the elderly population who were under the current health care programs. Statistical analysis on data from physical examination, hospitalization of the past years, from questionnaire and telephone interview was carried out in May, 2003. Data was from a hospital which implementing a health care program. Baseline population with a proportion of 4:1 was randomly selected to generate both module group and verification group. Baseline data was induced to make the verification group into regression model of module group and to generate the predictive value. Distinguished ability with area under ROC curve and the predictive veracity were verified through comparing the predictive incidence rate and actual incidence rate of every deciles group by Hosmer-Lemeshow test. Predictive veracity of the prediction model at population level was verified through comparing the predictive 6-year incidence rates of ICVD with actual 6-year accumulative incidence rates of ICVD with error rate calculated. The samples included 2271 males over the age of 65 with 1817 people for modeling population and 454 for verified population. All of the samples were stratified into two layers to establish hierarchical Cox proportional hazard regression model, including one advanced age group (greater than or equal to 75 years old), and another elderly group (less than 75 years old). Data from the statically analysis showed that the risk factors in aged group were age, systolic blood pressure, serum creatinine level, fasting blood glucose level, while protective factor was high density lipoprotein;in advanced age group, the risk factors were body weight index, systolic blood pressure, serum total cholesterol level, serum creatinine level, fasting blood glucose level, while protective factor was HDL-C. The area under the ROC curve (AUC) and 95%CI were 0.723 and 0.687 - 0.759 respectively. Discriminating power was good. All individual predictive ICVD cumulative incidence and actual incidence were analyzed using Hosmer-Lemeshow test, χ(2) = 1.43, P = 0.786, showing that the predictive veracity was good. The stratified Cox Hazards Regression model was used to establish prediction model of the aged male population under a certain health care program. The common prediction factor of the two age groups were: systolic blood pressure, serum creatinine level, fasting blood glucose level and HDL-C. The area under the ROC curve of the verification group was 0.723, showing that the distinguished ability was good and the predict ability at the individual level and at the group level were also satisfactory. It was feasible to using Cox Proportional Hazards Regression Model for predicting the population groups.

Statistical modeling of landslide hazard using GIS

Treesearch

Peter V. Gorsevski; Randy B. Foltz; Paul E. Gessler; Terrance W. Cundy

2001-01-01

A model for spatial prediction of landslide hazard was applied to a watershed affected by landslide events that occurred during the winter of 1995-96, following heavy rains, and snowmelt. Digital elevation data with 22.86 m x 22.86 m resolution was used for deriving topographic attributes used for modeling. The model is based on the combination of logistic regression...

Kawasaki Disease Increases the Incidence of Myopia.

PubMed

Kung, Yung-Jen; Wei, Chang-Ching; Chen, Liuh An; Chen, Jiin Yi; Chang, Ching-Yao; Lin, Chao-Jen; Lim, Yun-Ping; Tien, Peng-Tai; Chen, Hsuan-Ju; Huang, Yong-San; Lin, Hui-Ju; Wan, Lei

2017-01-01

The prevalence of myopia has rapidly increased in recent decades and has led to a considerable global public health concern. In this study, we elucidate the relationship between Kawasaki disease (KD) and the incidence of myopia. We used Taiwan's National Health Insurance Research Database to conduct a population-based cohort study. We identified patients diagnosed with KD and individuals without KD who were selected by frequency matched based on sex, age, and the index year. The Cox proportional hazards regression model was used to estimate the hazard ratio and 95% confidence intervals for the comparison of the 2 cohorts. The log-rank test was used to test the incidence of myopia in the 2 cohorts. A total of 532 patients were included in the KD cohort and 2128 in the non-KD cohort. The risk of myopia (hazard ratio, 1.31; 95% confidence interval, 1.08-1.58; P < 0.01) was higher among patients with KD than among those in the non-KD cohort. The Cox proportional hazards regression model showed that irrespective of age, gender, and urbanization, Kawasaki disease was an independent risk factor for myopia. Patients with Kawasaki disease exhibited a substantially higher risk for developing myopia.

Assessing the effect of a partly unobserved, exogenous, binary time-dependent covariate on survival probabilities using generalised pseudo-values.

PubMed

Pötschger, Ulrike; Heinzl, Harald; Valsecchi, Maria Grazia; Mittlböck, Martina

2018-01-19

Investigating the impact of a time-dependent intervention on the probability of long-term survival is statistically challenging. A typical example is stem-cell transplantation performed after successful donor identification from registered donors. Here, a suggested simple analysis based on the exogenous donor availability status according to registered donors would allow the estimation and comparison of survival probabilities. As donor search is usually ceased after a patient's event, donor availability status is incompletely observed, so that this simple comparison is not possible and the waiting time to donor identification needs to be addressed in the analysis to avoid bias. It is methodologically unclear, how to directly address cumulative long-term treatment effects without relying on proportional hazards while avoiding waiting time bias. The pseudo-value regression technique is able to handle the first two issues; a novel generalisation of this technique also avoids waiting time bias. Inverse-probability-of-censoring weighting is used to account for the partly unobserved exogenous covariate donor availability. Simulation studies demonstrate unbiasedness and satisfying coverage probabilities of the new method. A real data example demonstrates that study results based on generalised pseudo-values have a clear medical interpretation which supports the clinical decision making process. The proposed generalisation of the pseudo-value regression technique enables to compare survival probabilities between two independent groups where group membership becomes known over time and remains partly unknown. Hence, cumulative long-term treatment effects are directly addressed without relying on proportional hazards while avoiding waiting time bias.

Association Between Physical Therapy and Risk of Coronary Artery Disease and Dyslipidemia Among Osteoarthritis Patients: A Nationwide Database Study.

PubMed

Yeh, Huan-Jui; Chou, Yiing-Jenq; Yang, Nan-Ping; Cheng, Chi-Chia; Huang, Nicole

2016-01-01

To provide empirical evidence on the effect of early physical therapy (PT) within the first year of osteoarthritis (OA) diagnosis on reduction in OA-related comorbidities in patients with OA. Retrospective cohort study. The study was conducted using a nationally representative sample of 1 million National Health Insurance enrollees. Newly diagnosed patients with OA (N=13,545). One-to-one propensity score matching was used to match patients who received PT within the first year of OA diagnosis (PT group; n=3403) with an equal number of patients with OA who did not receive PT (non-PT group). Not applicable. The 4-year cumulative risk of comorbidities including coronary artery disease (CAD), diabetes mellitus, dyslipidemia, osteoporosis, gastrointestinal tract ulcer, and renal failure was estimated. A Cox proportional hazards regression analysis was performed to identify the dose-response relation between the PT dosage and the risk of OA-related comorbidities. A total of 3403 patients (25.1%) received PT within the first year of OA diagnosis. The PT group had a significantly lower 4-year cumulative risk of dyslipidemia (P=.05) and a potentially lower 4-year cumulative risk of CAD (P=.09). After adjusting for other potential confounders, the Cox proportional hazards regression analysis showed that patients with OA who received a high PT dosage had a low risk of CAD and dyslipidemia. Patients with OA who received PT had a lower risk of OA-related comorbidities such as dyslipidemia or CAD. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Dietary Sodium Consumption Predicts Future Blood Pressure and Incident Hypertension in the Japanese Normotensive General Population

PubMed Central

Takase, Hiroyuki; Sugiura, Tomonori; Kimura, Genjiro; Ohte, Nobuyuki; Dohi, Yasuaki

2015-01-01

Background Although there is a close relationship between dietary sodium and hypertension, the concept that persons with relatively high dietary sodium are at increased risk of developing hypertension compared with those with relatively low dietary sodium has not been studied intensively in a cohort. Methods and Results We conducted an observational study to investigate whether dietary sodium intake predicts future blood pressure and the onset of hypertension in the general population. Individual sodium intake was estimated by calculating 24-hour urinary sodium excretion from spot urine in 4523 normotensive participants who visited our hospital for a health checkup. After a baseline examination, they were followed for a median of 1143 days, with the end point being development of hypertension. During the follow-up period, hypertension developed in 1027 participants (22.7%). The risk of developing hypertension was higher in those with higher rather than lower sodium intake (hazard ratio 1.25, 95% CI 1.04 to 1.50). In multivariate Cox proportional hazards regression analysis, baseline sodium intake and the yearly change in sodium intake during the follow-up period (as continuous variables) correlated with the incidence of hypertension. Furthermore, both the yearly increase in sodium intake and baseline sodium intake showed significant correlations with the yearly increase in systolic blood pressure in multivariate regression analysis after adjustment for possible risk factors. Conclusions Both relatively high levels of dietary sodium intake and gradual increases in dietary sodium are associated with future increases in blood pressure and the incidence of hypertension in the Japanese general population. PMID:26224048

[Survival following the first admission in an integrated dual disorders treatment ward (IDDTW): preliminary results from a cohort study].

PubMed

Gimelfarb, Yuri; Becatel, Ety; Wolf, Aviva; Baruch, Yehuda

2014-01-01

Dual disorders (co-occurring severe mental illness [SMI] and substance abuse disorders in the same person) are extremely common among patients receiving mental health services. Dual disorders are associated with increased all-cause mortality, as compared with patients with SMI. Scientific evidence is lacking on the survival of dual disorders subjects, who had psychiatric inpatient care. To determine the long term survival rates of patients after the first admission in an IDDTW and to identify their baseline predictors. The charts of 258 subjects admitted to IDDTW during the period 2002-2004 were assessed at least 8 years after the first admission. Psychiatric diagnoses were established and grouped according to the International Statistical Classification of Diseases and Related Health Problems 10th edition (ICD-10). The Kaplan-Meier survival analysis was used to estimate the cumulative survival rates, and the predictive values of different variables were assessed by Cox proportional-hazards regression model. The cumulative 1-, 2-, 4-, 6- and 8-year survival rates of all subjects were 98.06%, 96.51%, 91.47, 86.43% and 81.78%, respectively, without statistically significant differences between subgroups of psychiatric diagnoses. Multivariate Cox regression analysis revealed that the age at death was the only independent predictor of all-cause mortality (hazard ratio = .96; 95% confidence interval .93 to .99; p < .009). Those of young age are at a particularly low risk of long term survival. More targeted health care is required to address the specific needs of this vulnerable subgroup. Further research of survival into specific risk groups is required.

Evaluation of clinical and histopathologic prognostic factors for survival in canine osteosarcoma of the extracranial flat and irregular bones.

PubMed

Kruse, M A; Holmes, E S; Balko, J A; Fernandez, S; Brown, D C; Goldschmidt, M H

2013-07-01

Osteosarcoma is the most common bone tumor in dogs. However, current literature focuses primarily on appendicular osteosarcoma. This study examined the prognostic value of histological and clinical factors in flat and irregular bone osteosarcomas and hypothesized that clinical factors would have a significant association with survival time while histological factors would not. All osteosarcoma biopsy samples of the vertebra, rib, sternum, scapula, or pelvis were reviewed while survival information and clinical data were obtained from medical records, veterinarians, and owners. Forty-six dogs were included in the analysis of histopathological variables and 27 dogs with complete clinical data were included in the analysis of clinical variables. In the histopathologic cox regression model, there was no significant association between any histologic feature of osteosarcoma, including grade, and survival time. In the clinical cox regression model, there was a significant association between the location of the tumor and survival time as well as between the percent elevation of alkaline phosphatase (ALP) above normal and survival time. Controlling for ALP elevation, dogs with osteosarcoma located in the scapula had a significantly greater hazard for death (2.8) compared to dogs with tumors in other locations. Controlling for tumor location, every 100% increase in ALP from normal increased the hazard for death by 1.7. For canine osteosarcomas of the flat and irregular bones, histopathological features, including grade do not appear to be rigorous predictors of survival. Clinical variables such as increased ALP levels and tumor location in the scapula were associated with decreased survival times.

21 CFR 120.7 - Hazard analysis.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Hazard analysis. 120.7 Section 120.7 Food and... hazards. The written hazard analysis shall consist of at least the following: (1) Identification of food..., including food hazards that can occur before, during, and after harvest. The hazard analysis shall be...

21 CFR 120.7 - Hazard analysis.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Hazard analysis. 120.7 Section 120.7 Food and... hazards. The written hazard analysis shall consist of at least the following: (1) Identification of food..., including food hazards that can occur before, during, and after harvest. The hazard analysis shall be...

21 CFR 120.7 - Hazard analysis.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Hazard analysis. 120.7 Section 120.7 Food and... hazards. The written hazard analysis shall consist of at least the following: (1) Identification of food..., including food hazards that can occur before, during, and after harvest. The hazard analysis shall be...

21 CFR 120.7 - Hazard analysis.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Hazard analysis. 120.7 Section 120.7 Food and... hazards. The written hazard analysis shall consist of at least the following: (1) Identification of food..., including food hazards that can occur before, during, and after harvest. The hazard analysis shall be...

ELASTIC NET FOR COX’S PROPORTIONAL HAZARDS MODEL WITH A SOLUTION PATH ALGORITHM

PubMed Central

Wu, Yichao

2012-01-01

For least squares regression, Efron et al. (2004) proposed an efficient solution path algorithm, the least angle regression (LAR). They showed that a slight modification of the LAR leads to the whole LASSO solution path. Both the LAR and LASSO solution paths are piecewise linear. Recently Wu (2011) extended the LAR to generalized linear models and the quasi-likelihood method. In this work we extend the LAR further to handle Cox’s proportional hazards model. The goal is to develop a solution path algorithm for the elastic net penalty (Zou and Hastie (2005)) in Cox’s proportional hazards model. This goal is achieved in two steps. First we extend the LAR to optimizing the log partial likelihood plus a fixed small ridge term. Then we define a path modification, which leads to the solution path of the elastic net regularized log partial likelihood. Our solution path is exact and piecewise determined by ordinary differential equation systems. PMID:23226932

VEGETATION COVER ANALYSIS OF HAZARDOUS WASTE SITES IN UTAH AND ARIZONA USING HYPERSPECTRAL REMOTE SENSING

DOE Office of Scientific and Technical Information (OSTI.GOV)

Serrato, M.; Jungho, I.; Jensen, J.

2012-01-17

Remote sensing technology can provide a cost-effective tool for monitoring hazardous waste sites. This study investigated the usability of HyMap airborne hyperspectral remote sensing data (126 bands at 2.3 x 2.3 m spatial resolution) to characterize the vegetation at U.S. Department of Energy uranium processing sites near Monticello, Utah and Monument Valley, Arizona. Grass and shrub species were mixed on an engineered disposal cell cover at the Monticello site while shrub species were dominant in the phytoremediation plantings at the Monument Valley site. The specific objectives of this study were to: (1) estimate leaf-area-index (LAI) of the vegetation using threemore » different methods (i.e., vegetation indices, red-edge positioning (REP), and machine learning regression trees), and (2) map the vegetation cover using machine learning decision trees based on either the scaled reflectance data or mixture tuned matched filtering (MTMF)-derived metrics and vegetation indices. Regression trees resulted in the best calibration performance of LAI estimation (R{sup 2} > 0.80). The use of REPs failed to accurately predict LAI (R{sup 2} < 0.2). The use of the MTMF-derived metrics (matched filter scores and infeasibility) and a range of vegetation indices in decision trees improved the vegetation mapping when compared to the decision tree classification using just the scaled reflectance. Results suggest that hyperspectral imagery are useful for characterizing biophysical characteristics (LAI) and vegetation cover on capped hazardous waste sites. However, it is believed that the vegetation mapping would benefit from the use of 1 higher spatial resolution hyperspectral data due to the small size of many of the vegetation patches (< 1m) found on the sites.« less

A CD4+ cell count <200 cells per cubic millimeter at 2 years after initiation of combination antiretroviral therapy is associated with increased mortality in HIV-infected individuals with viral suppression.

PubMed

Loutfy, Mona R; Genebat, Miguel; Moore, David; Raboud, Janet; Chan, Keith; Antoniou, Tony; Milan, David; Shen, Anya; Klein, Marina B; Cooper, Curtis; Machouf, Nima; Rourke, Sean B; Rachlis, Anita; Tsoukas, Chris; Montaner, Julio S G; Walmsley, Sharon L; Smieja, Marek; Bayoumi, Ahmed; Mills, Edward; Hogg, Robert S

2010-12-01

To determine the long-term impact of immunologic discordance (viral load <50 copies/mL and CD4+ count <=200 cells/mm3) in antiretroviral-naive patients initiating combination antiretroviral therapy (cART). Our analysis included antiretroviral-naive individuals from a population-based Canadian Observational Cohort that initiated cART after January 1, 2000, and achieved virologic suppression. Multivariable Cox proportional hazards regression was used to examine the association between 1-year and 2-year immunologic discordance and time to death from all-causes. Correlates of immunologic discordance were assessed with logistic regression. Immunologic discordance was observed in 19.9% (404 of 2028) and 10.2% (176 of 1721) of individuals at 1 and 2 years after cART initiation, respectively. Two-year immunologic discordance was associated with an increased risk of death [adjusted hazard ratio = 2.69; 95% confidence interval (CI): 1.26 to 5.78]. One-year immunologic discordance was not associated with death (adjusted hazard ratio = 1.12; 95% CI: 0.54 to 2.30). Two-year immunologic discordance was associated with older age (aOR per decade = 1.23; 95% CI: 1.03 to 1.48), male gender (aOR = 1.86; 95% CI: 1.09 to 3.16), injection drug use (aOR = 2.75; 95% CI: 1.81 to 4.17), and lower baseline CD4+ count (aOR per 100 cells = 0.24; 95% CI: 0.19 to 0.31) and viral load (aOR per log10 copies/mL = 0.46; 95% CI: 0.33 to 0.65). Immunologic discordance after 2 years of cART in antiretroviral-naive individuals was significantly associated with an increased risk of mortality.

The prognostic value of early repolarization with ST-segment elevation in African Americans.

PubMed

Perez, Marco V; Uberoi, Abhimanyu; Jain, Nikhil A; Ashley, Euan; Turakhia, Mintu P; Froelicher, Victor

2012-04-01

Increased prevalence of classic early repolarization, defined as ST-segment elevation (STE) in the absence of acute myocardial injury, in African Americans is well established. The prognostic value of this pattern in different ethnicities remains controversial. Measure association between early repolarization and cardiovascular mortality in African Americans. The resting electrocardiograms of 45,829 patients were evaluated at the Palo Alto Veterans Affairs Hospital. Subjects with inpatient status or electrocardiographic evidence of acute myocardial infarction were excluded, leaving 29,281 subjects. ST-segment elevation, defined as an elevation of >0.1 mV at the end of the QRS, was electronically flagged and visually adjudicated by 3 observers blinded to outcomes. An association between ethnicity and early repolarization was measured by using multivariate logistic regression. We analyzed associations between early repolarization and cardiovascular mortality by using the Cox proportional hazards regression analysis. Subjects were 13% women and 13.3% African Americans, with an average age of 55 years and followed for an average of 7.6 years, resulting in 1995 cardiovascular deaths. There were 479 subjects with lateral STE and 185 with inferior STE. After adjustment for age, sex, heart rate, and coronary artery disease, African American ethnicity was associated with lateral or inferior STE (odds ratio 3.1; P = .0001). While lateral or inferior STE in non-African Americans was independently associated with cardiovascular death (hazard ratio 1.6; P = .02), it was not associated with cardiovascular death in African Americans (hazard ratio 0.75; P = .50). Although early repolarization is more prevalent in African Americans, it is not predictive of cardiovascular death in this population and may represent a distinct electrophysiologic phenomenon. Copyright © 2012 Heart Rhythm Society. All rights reserved.

Risk of schizophrenia and minority status: a comparison of the Swedish-speaking minority and the Finnish-speaking majority in Finland.

PubMed

Suvisaari, Jaana; Opler, Mark; Lindbohm, Marja-Liisa; Sallmén, Markku

2014-11-01

Approximately five percent of the Finnish population are Swedish-speaking and have higher socioeconomic position and longer life expectancy than the Finnish-speaking majority. Previous studies have not investigated whether Swedish-speaking Finns have lower risk of schizophrenia spectrum disorders (SSD) than Finnish-speaking Finns. We investigated this in a representative sample of 47 445 Finns born in 1972-1984. Hazard ratios of SSD between language groups were assessed with conditional proportional hazards regression. Sex, parental ages at birth, paternal employment around conception, parental psychosis and place and residence in the capital area were used as other explanatory variables. The prevalence of SSD was 0.7% in the Swedish-speaking minority and 1.5% in the Finnish-speaking majority. In the adjusted regression model, belonging to the Swedish-speaking minority was associated with lower risk of SSD (hazard ratio (HR) 0.41, 95% confidence interval (CI) 0.24-0.69). In a subset analysis by gender, the protective effect was evident among Swedish-speaking males (HR 0.32, 95% CI 0.15-0.68) but marginal in females (HR 0.75, 95% CI 0.41-1.37). Parental psychosis and place of birth in the capital area were associated with higher risk of SSD, whereas paternal employment at the time of conception was associated with lower risk of SSD. Our results support the role of social factors in the etiology of schizophrenia. Belonging to a minority with high socioeconomic status and social capital may be protective against schizophrenia, especially for males. Copyright © 2014 Elsevier B.V. All rights reserved.

Complex association of serum alanine aminotransferase with the risk of future cardiovascular disease in type 2 diabetes.

PubMed

Afarideh, Mohsen; Aryan, Zahra; Ghajar, Alireza; Noshad, Sina; Nakhjavani, Manouchehr; Baber, Usman; Mechanick, Jeffrey I; Esteghamati, Alireza

2016-11-01

We aimed to determine the prospective association between baseline serum levels of alanine aminotransferase (ALT) and the incident cardiovascular disease (CVD) in people with type 2 diabetes. In an open cohort setting, people with type 2 diabetes were followed for their first ever CVD presentation from 1995 to 2015. Statistical methods included Cox regression analysis for reporting of hazard ratios (HRs), artificial neural network modelings, and risk reclassification analyses. We found a nearly constant CVD hazard with baseline serum ALT levels below the 30 IU/L mark, whereas baseline serum ALT levels ≥ 30 IU/L remained an independent predictor of lower CVD rates in patients with type 2 diabetes in the final multivariate Cox proportional hazards regression model (HR: 0.204, 95%CI [0.060-0.689], p for trend value = 0.006). Age, male gender and fasting plasma insulin levels independently predicted baseline serum ALT ≥ 30 IU/L among the population cohort. Augmentation of serum ALT into the weighted Framingham risk score resulted in a considerable net reclassification improvement (NRI) of coronary heart disease (CHD) risk prediction in the study population (NRI = 9.05% (8.01%-10.22%), p value < 0.05). Serum ALT could successfully reclassify about 9% of the population with type 2 diabetes across the CHD-affected and CHD-free categories. Overall, our findings demonstrate a complex and nonlinear relationship for the risk of future CVD by baseline serum ALT levels in patients with type 2 diabetes. Further studies are warranted to confirm whether this complex association could be translated into a clearly visible U or J-shaped figure. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Canister Storage Building (CSB) Hazard Analysis Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

POWERS, T.B.

2000-03-16

This report describes the methodology used in conducting the Canister Storage Building (CSB) Hazard Analysis to support the final CSB Safety Analysis Report and documents the results. This report describes the methodology used in conducting the Canister Storage Building (CSB) hazard analysis to support the CSB final safety analysis report (FSAR) and documents the results. The hazard analysis process identified hazardous conditions and material-at-risk, determined causes for potential accidents, identified preventive and mitigative features, and qualitatively estimated the frequencies and consequences of specific occurrences. The hazard analysis was performed by a team of cognizant CSB operations and design personnel, safetymore » analysts familiar with the CSB, and technical experts in specialty areas. The material included in this report documents the final state of a nearly two-year long process. Attachment A provides two lists of hazard analysis team members and describes the background and experience of each. The first list is a complete list of the hazard analysis team members that have been involved over the two-year long process. The second list is a subset of the first list and consists of those hazard analysis team members that reviewed and agreed to the final hazard analysis documentation. The material included in this report documents the final state of a nearly two-year long process involving formal facilitated group sessions and independent hazard and accident analysis work. The hazard analysis process led to the selection of candidate accidents for further quantitative analysis. New information relative to the hazards, discovered during the accident analysis, was incorporated into the hazard analysis data in order to compile a complete profile of facility hazards. Through this process, the results of the hazard and accident analyses led directly to the identification of safety structures, systems, and components, technical safety requirements, and other controls required to protect the public, workers, and environment.« less

Immune reconstitution inflammatory syndrome associated with Kaposi sarcoma: higher incidence and mortality in Africa than in the UK.

PubMed

Letang, Emilio; Lewis, James J; Bower, Mark; Mosam, Anisa; Borok, Margareth; Campbell, Thomas B; Naniche, Denise; Newsom-Davis, Tom; Shaik, Fahmida; Fiorillo, Suzanne; Miro, Jose M; Schellenberg, David; Easterbrook, Philippa J

2013-06-19

To assess the incidence, predictors, and outcomes of Kaposi sarcoma-associated paradoxical immune reconstitution inflammatory syndrome (KS-IRIS) in antiretroviral therapy (ART)-naive HIV-infected patients with Kaposi sarcoma initiating ART in both well resourced and limited-resourced settings. Pooled analysis of three prospective cohorts of ART-naive HIV-infected patients with Kaposi sarcoma from sub-Saharan Africa (SSA) and one from the UK. KS-IRIS case definition was standardized across sites. Cox regression and Kaplan-Meier survival analysis were used to identify the incidence and predictors of KS-IRIS and Kaposi sarcoma-associated mortality. Fifty-eight of 417 (13.9%) eligible individuals experienced KS-IRIS with an incidence 2.5 times higher in the African vs. European cohorts (P=0.001). ART alone as initial Kaposi sarcoma treatment (hazard ratio 2.97, 95% confidence interval (CI) 1.02-8.69); T1 Kaposi sarcoma stage (hazard ratio 2.96, 95% CI 1.26-6.94); and plasma HIV-1 RNA more than 5 log₁₀ copies/ml (hazard ratio 2.14, 95% CI 1.25-3.67) independently predicted KS-IRIS at baseline. Detectable plasma Kaposi sarcoma-associated herpes virus (KSHV) DNA additionally predicted KS-IRIS among the 259 patients with KSHV DNA assessed (hazard ratio 2.98, 95% CI 1.23-7.19). Nineteen KS-IRIS patients died, all in SSA. Kaposi sarcoma mortality was 3.3-fold higher in Africa, and was predicted by KS-IRIS (hazard ratio 19.24, CI 7.62-48.58), lack of chemotherapy (hazard ratio 2.35, 95% CI 1.09-5.05), pre-ART CD4 cell count less than 200 cells/μl (hazard ratio 2.04, 95% CI 0.99-4.2), and detectable baseline KSHV DNA (hazard ratio 2.12, 95% CI 0.94-4.77). KS-IRIS incidence and mortality are higher in SSA than in the UK. This is largely explained by the more advanced Kaposi sarcoma disease and lower chemotherapy availability. KS-IRIS is a major contributor to Kaposi sarcoma-associated mortality in Africa. Our results support the need to increase awareness on KS-IRIS, encourage earlier presentation, referral and diagnosis of Kaposi sarcoma, and advocate on access to systemic chemotherapy in Africa. © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins

Screening for hazardous drinking using the Michigan Alcohol Screening Test-Geriatric Version (MAST-G) in elderly persons with acute cerebrovascular accidents.

PubMed

Johnson-Greene, Doug; McCaul, Mary E; Roger, Patricia

2009-09-01

Effective and valid screening methods are needed to identify hazardous drinking in elderly persons with new onset acute medical illness. The goal of the current study was to examine the effectiveness of the Michigan Alcohol Screening Test-Geriatric Version (MAST-G) in identifying hazardous drinking among elderly patients with acute cerebrovascular accidents (CVA) and to compare the effectiveness of 2 shorter versions of the MAST-G with the full instrument. The study sample included 100 men and women who averaged 12 days posthemorrhagic or ischemic CVA admitted to a rehabilitation unit and who were at least 50 years of age and free of substance use other than alcohol. This cross-sectional validation study compared the 24-item full MAST-G, the 10-item Short MAST-G (SMAST-G), and a 2-item regression analysis derived Mini MAST-G (MMAST-G) to the reference standard of hazardous drinking during the past 3 months. Alcohol use was collected using the Timeline Followback (TLFB). Recent and lifetime alcohol-related consequences were collected using the Short Inventory of Problems (SIP). Nearly one-third (28%) of the study sample met the World Health Organization (WHO) criteria for hazardous drinking. Moderately strong associations were found for the MAST-G, SMAST-G, and MMAST-G with alcohol quantity and frequency and recent and lifetime alcohol consequences. All 3 MAST-G versions could differentiate hazardous from nonhazardous drinkers and had nearly identical area under the curve characteristics. Comparable sensitivity was found across the 3 MAST-G measures. The optimal screening threshold for hazardous drinking was 5 for the MAST-G, 2 for the SMAST-G, and 1 for the MMAST-G. The 10-item SMAST-G and 2-item MMAST-G are brief screening tests that show comparable effectiveness in detecting hazardous drinking in elderly patients with acute CVA compared with the full 24-item MAST-G. Implications for research and clinical practice are discussed.

Hazardous alcohol use and receipt of risk-reduction counseling among U.S. veterans of the wars in Iraq and Afghanistan.

PubMed

Calhoun, Patrick S; Elter, John R; Jones, Everett R; Kudler, Harold; Straits-Tröster, Kristy

2008-11-01

Military service in Afghanistan (Operation Enduring Freedom [OEF]) and Iraq (Operation Iraqi Freedom [OIF]) has been associated with high rates of mental health problems. Relatively little is known, however, about the prevalence of risky drinking among OEF/OIF veterans using U.S. Department of Veterans Affairs (VA) health care. This study examined the prevalence of hazardous alcohol use among OEF/OIF veterans and the incidence of alcohol risk-reduction counseling offered by VA providers. A secondary analysis of data extracted from the VA outpatient Survey of Healthcare Experiences of Patients, a stratified random sample of VA clinic users from the fiscal year 2005 (October 1, 2004, to September 30, 2005), was conducted. The Alcohol Use Disorders Identification Test (AUDIT-C) was scored to assess hazardous drinking and possible alcohol use disorder (AUD). Patient report of alcohol counseling by a VA provider in the past year was queried for those with risky drinking behavior. The association of demographic variables with potentially hazardous alcohol use, alcohol use disorder, and receipt of alcohol risk-reduction counseling was estimated using logistic regression. Overall, 40% of the sample screened positive for potentially hazardous alcohol use, and 22% screened positive for possible AUD. Only 31% of those with hazardous drinking behavior, however, reported being counseled to cut back or to not drink alcohol. Higher AUDIT-C scores were associated with increased likelihood of risk-reduction counseling. Among patients reporting hazardous drinking, there was a trend for those with less education and lower income to be more likely to report receiving advice about their drinking. Hazardous alcohol use is prevalent among OEF/OIF veterans seeking VA health care. There is a need for increased vigilance and action to identify and counsel at-risk veterans in this population. Copyright 2008 Physicians Postgraduate Press, Inc.

Stereotactic Body Radiotherapy for Early-stage Non-small-cell Lung Cancer in Patients 80 Years and Older: A Multi-center Analysis.

PubMed

Cassidy, Richard J; Patel, Pretesh R; Zhang, Xinyan; Press, Robert H; Switchenko, Jeffrey M; Pillai, Rathi N; Owonikoko, Taofeek K; Ramalingam, Suresh S; Fernandez, Felix G; Force, Seth D; Curran, Walter J; Higgins, Kristin A

2017-09-01

Stereotactic body radiotherapy (SBRT) is the standard of care for medically inoperable early-stage non-small-cell lung cancer. Despite the limited number of octogenarians and nonagenarians on trials of SBRT, its use is increasingly being offered in these patients, given the aging cancer population, medical fragility, or patient preference. Our purpose was to investigate the efficacy, safety, and survival of patients ≥ 80 years old treated with definitive lung SBRT. Patients who underwent SBRT were reviewed from 2009 to 2015 at 4 academic centers. Patients diagnosed at ≥ 80 years old were included. Kaplan-Meier and multivariate logistic regression and Cox proportional hazard regression analyses were performed. Recursive partitioning analysis was done to determine a subgroup of patients most likely to benefit from therapy. A total of 58 patients were included, with a median age of 84.9 years (range, 80.1-95.2 years), a median follow-up time of 19.9 months (range, 6.9-64.9 months), a median fraction size of 10.0 Gy (range, 7.0-20.0 Gy), and a median number of fractions of 5.0 (range, 3.0-8.0 fractions). On multivariate analysis, higher Karnofsky performance status (KPS) was associated with higher local recurrence-free survival (hazard ratio [HR], 0.92; P < .01), regional recurrence-free survival (HR, 0.94; P < .01), and overall survival (HR, 0.91; P < .01). On recursive partitioning analysis, patients with KPS ≥ 75 had improved 3-year cancer-specific and overall survival (99.4% and 91.9%, respectively) compared with patients with KPS < 75 (47.8% and 23.6%, respectively; P < .01). Definitive lung SBRT for early-stage non-small-cell lung cancer was efficacious and safe in patients ≥ 80 years old. Patients with a KPS of ≥ 75 derived the most benefit from therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

Hydrothermal Liquefaction Treatment Preliminary Hazard Analysis Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lowry, Peter P.; Wagner, Katie A.

A preliminary hazard assessment was completed during February 2015 to evaluate the conceptual design of the modular hydrothermal liquefaction treatment system. The hazard assessment was performed in 2 stages. An initial assessment utilizing Hazard Identification and Preliminary Hazards Analysis (PHA) techniques identified areas with significant or unique hazards (process safety-related hazards) that fall outside of the normal operating envelope of PNNL and warranted additional analysis. The subsequent assessment was based on a qualitative What-If analysis. This analysis was augmented, as necessary, by additional quantitative analysis for scenarios involving a release of hazardous material or energy with the potential for affectingmore » the public.« less

Earthquake impact on settlements: the role of urban and structural morphology

NASA Astrophysics Data System (ADS)

Bostenaru Dan, M.; Armas, I.

2015-10-01

This study is aimed to create an alternative to the classical GIS representation of the impact of earthquake hazards on urban areas. To accomplish this, the traditional map was revised, so that it can cope with contemporary innovative ways of planning, namely strategic planning. As in the theory of fractals, the building dimension and the urban neighbourhood dimension are addressed as different geographic scales between which lessons for decisions can be learned through regression. The interaction between the two scales is useful when looking for alternatives, for the completion of a GIS analysis, and in choosing the landmarks, which, in the case of hazards, become strategic elements in strategic planning. A methodology to innovate mapping as a digital means for analysing and visualising the impact of hazards is proposed. This method relies on concepts from various geography, urban planning, structural engineering and architecture approaches related to disaster management. The method has been tested at the building scale for the N-S Boulevard in Bucharest, Romania, called Magheru. At the urban scale, an incident database has been created, in which the case study for the building level can be mapped. The paper presented is part of a larger research work, which addresses decision making using the framework shown here. The main value of the paper is in proposing a conceptual framework to deconstruct the map for digital earthquake disaster impact analysis and representation. The originality of the concept consists in the representation of elements at different scales considered to be of different levels of importance in the urban tissue, according to the analysis to be performed on them.

Psychosocial Hazard Analysis in a Heterogeneous Workforce: Determinants of Work Stress in Blue- and White-Collar Workers of the European Steel Industry

PubMed Central

Metzler, Yannick Arnold; Bellingrath, Silja

2017-01-01

The European steel industry’s workforce is highly heterogeneous and consists of various occupational groups, presumably facing different psychosocial stressors. The few existing studies on the subject mainly focused on physical constraints of blue-collar workers, whereas the supposable psychosocial workload received only little research attention. This is remarkable considering the challenges associated with statutory required risk assessment of psychosocial hazards. Valid measures of hazard analysis must account for various stressors and reliably identify them, also between occupational groups. The present study, based on a sample of blue- and white-collar workers (N = 124) from the European steel industry, aims to provide a first insight into psychosocial stressors and strain at work in this rarely researched industrial sector. Furthermore, two well-known theoretical roadmaps in job analysis are examined regarding their utility for risk assessment in heterogeneous workforces: the German standard version of the Copenhagen Psychosocial Questionnaire (COPSOQ) and the short version of the effort–reward imbalance questionnaire. Hierarchical multiple regression analyses revealed that the COPSOQ was better suited to predict various strain indices in the present sample. Especially stressors relating to socioemotional aspects, such as work-privacy conflict, revealed a reasonable impact, indicating the need for comprehensive solutions at the organizational level instead of solutions focusing on single workplaces. To conclude, a broadly diversified and validated approach in psychosocial risk assessment is needed to adequately assess the variety of psychosocial factors at work and in different occupational groups. PMID:28861410

Simulation program for estimating statistical power of Cox's proportional hazards model assuming no specific distribution for the survival time.

PubMed

Akazawa, K; Nakamura, T; Moriguchi, S; Shimada, M; Nose, Y

1991-07-01

Small sample properties of the maximum partial likelihood estimates for Cox's proportional hazards model depend on the sample size, the true values of regression coefficients, covariate structure, censoring pattern and possibly baseline hazard functions. Therefore, it would be difficult to construct a formula or table to calculate the exact power of a statistical test for the treatment effect in any specific clinical trial. The simulation program, written in SAS/IML, described in this paper uses Monte-Carlo methods to provide estimates of the exact power for Cox's proportional hazards model. For illustrative purposes, the program was applied to real data obtained from a clinical trial performed in Japan. Since the program does not assume any specific function for the baseline hazard, it is, in principle, applicable to any censored survival data as long as they follow Cox's proportional hazards model.

Body mass index in relation to serum prostate-specific antigen levels and prostate cancer risk.

PubMed

Bonn, Stephanie E; Sjölander, Arvid; Tillander, Annika; Wiklund, Fredrik; Grönberg, Henrik; Bälter, Katarina

2016-07-01

High Body mass index (BMI) has been directly associated with risk of aggressive or fatal prostate cancer. One possible explanation may be an effect of BMI on serum levels of prostate-specific antigen (PSA). To study the association between BMI and serum PSA as well as prostate cancer risk, a large cohort of men without prostate cancer at baseline was followed prospectively for prostate cancer diagnoses until 2015. Serum PSA and BMI were assessed among 15,827 men at baseline in 2010-2012. During follow-up, 735 men were diagnosed with prostate cancer with 282 (38.4%) classified as high-grade cancers. Multivariable linear regression models and natural cubic linear regression splines were fitted for analyses of BMI and log-PSA. For risk analysis, Cox proportional hazards regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) and natural cubic Cox regression splines producing standardized cancer-free probabilities were fitted. Results showed that baseline Serum PSA decreased by 1.6% (95% CI: -2.1 to -1.1) with every one unit increase in BMI. Statistically significant decreases of 3.7, 11.7 and 32.3% were seen for increasing BMI-categories of 25 < 30, 30 < 35 and ≥35 kg/m(2), respectively, compared to the reference (18.5 < 25 kg/m(2)). No statistically significant associations were seen between BMI and prostate cancer risk although results were indicative of a positive association to incidence rates of high-grade disease and an inverse association to incidence of low-grade disease. However, findings regarding risk are limited by the short follow-up time. In conclusion, BMI was inversely associated to PSA-levels. BMI should be taken into consideration when referring men to a prostate biopsy based on serum PSA-levels. © 2016 UICC.

Cox Regression Models with Functional Covariates for Survival Data.

PubMed

Gellar, Jonathan E; Colantuoni, Elizabeth; Needham, Dale M; Crainiceanu, Ciprian M

2015-06-01

We extend the Cox proportional hazards model to cases when the exposure is a densely sampled functional process, measured at baseline. The fundamental idea is to combine penalized signal regression with methods developed for mixed effects proportional hazards models. The model is fit by maximizing the penalized partial likelihood, with smoothing parameters estimated by a likelihood-based criterion such as AIC or EPIC. The model may be extended to allow for multiple functional predictors, time varying coefficients, and missing or unequally-spaced data. Methods were inspired by and applied to a study of the association between time to death after hospital discharge and daily measures of disease severity collected in the intensive care unit, among survivors of acute respiratory distress syndrome.

INTERNAL HAZARDS ANALYSIS FOR LICENSE APPLICATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

R.J. Garrett

2005-02-17

The purpose of this internal hazards analysis is to identify and document the internal hazards and potential initiating events associated with preclosure operations of the repository at Yucca Mountain. Internal hazards are those hazards presented by the operation of the facility and by its associated processes that can potentially lead to a radioactive release or cause a radiological hazard. In contrast to external hazards, internal hazards do not involve natural phenomena and external man-made hazards. This internal hazards analysis was performed in support of the preclosure safety analysis and the License Application for the Yucca Mountain Project. The methodology formore » this analysis provides a systematic means to identify internal hazards and potential initiating events that may result in a radiological hazard or radiological release during the repository preclosure period. These hazards are documented in tables of potential internal hazards and potential initiating events (Section 6.6) for input to the repository event sequence categorization process. The results of this analysis will undergo further screening and analysis based on the criteria that apply to the performance of event sequence analyses for the repository preclosure period. The evolving design of the repository will be re-evaluated periodically to ensure that internal hazards that have not been previously evaluated are identified.« less

Assessment of the spatial scaling behaviour of floods in the United Kingdom

NASA Astrophysics Data System (ADS)

Formetta, Giuseppe; Stewart, Elizabeth; Bell, Victoria

2017-04-01

Floods are among the most dangerous natural hazards, causing loss of life and significant damage to private and public property. Regional flood-frequency analysis (FFA) methods are essential tools to assess the flood hazard and plan interventions for its mitigation. FFA methods are often based on the well-known index flood method that assumes the invariance of the coefficient of variation of floods with drainage area. This assumption is equivalent to the simple scaling or self-similarity assumption for peak floods, i.e. their spatial structure remains similar in a particular, relatively simple, way to itself over a range of scales. Spatial scaling of floods has been evaluated at national scale for different countries such as Canada, USA, and Australia. According our knowledge. Such a study has not been conducted for the United Kingdom even though the standard FFA method there is based on the index flood assumption. In this work we present an integrated approach to assess of the spatial scaling behaviour of floods in the United Kingdom using three different methods: product moments (PM), probability weighted moments (PWM), and quantile analysis (QA). We analyse both instantaneous and daily annual observed maximum floods and performed our analysis both across the entire country and in its sub-climatic regions as defined in the Flood Studies Report (NERC, 1975). To evaluate the relationship between the k-th moments or quantiles and the drainage area we used both regression with area alone and multiple regression considering other explanatory variables to account for the geomorphology, amount of rainfall, and soil type of the catchments. The latter multiple regression approach was only recently demonstrated being more robust than the traditional regression with area alone that can lead to biased estimates of scaling exponents and misinterpretation of spatial scaling behaviour. We tested our framework on almost 600 rural catchments in UK considered as entire region and split in 11 sub-regions with 50 catchments per region on average. Preliminary results from the three different spatial scaling methods are generally in agreement and indicate that: i) only some of the peak flow variability is explained by area alone (approximately 50% for the entire country and ranging between the 40% and 70% for the sub-regions); ii) this percentage increases to 90% for the entire country and ranges between 80% and 95% for the sub-regions when the multiple regression is used; iii) the simple scaling hypothesis holds in all sub-regions with the exception of weak multi-scaling found in the regions 2 (North), and 5 and 6 (South East). We hypothesize that these deviations can be explained by heterogeneity in large scale precipitation and by the influence of the soil type (predominantly chalk) on the flood formation process in regions 5 and 6.

Linking local vulnerability to climatic hazard damage assessment for integrated river basin management

NASA Astrophysics Data System (ADS)

Hung, Hung-Chih; Liu, Yi-Chung; Chien, Sung-Ying

2015-04-01

1. Background Major portions of areas in Asia are expected to increase exposure and vulnerability to climate change and weather extremes due to rapid urbanization and overdevelopment in hazard-prone areas. To prepare and confront the potential impacts of climate change and related hazard risk, many countries have implemented programs of integrated river basin management. This has led to an impending challenge for the police-makers in many developing countries to build effective mechanism to assess how the vulnerability distributes over river basins, and to understand how the local vulnerability links to climatic (climate-related) hazard damages and risks. However, the related studies have received relatively little attention. This study aims to examine whether geographic localities characterized by high vulnerability experience significantly more damages owing to onset weather extreme events at the river basin level, and to explain what vulnerability factors influence these damages or losses. 2. Methods and data An indicator-based assessment framework is constructed with the goal of identifying composite indicators (including exposure, biophysical, socioeconomic, land-use and adaptive capacity factors) that could serve as proxies for attributes of local vulnerability. This framework is applied by combining geographical information system (GIS) techniques with multicriteria decision analysis (MCDA) to evaluate and map integrated vulnerability to climatic hazards across river basins. Furthermore, to explain the relationship between vulnerability factors and disaster damages, we develop a disaster damage model (DDM) based on existing disaster impact theory. We then synthesize a Zero-Inflated Poisson regression model with a Tobit regression analysis to identify and examine how the disaster impacts and vulnerability factors connect to typhoon disaster damages and losses. To illustrate the proposed methodology, the study collects data on the vulnerability attributes of the Kaoping, Tsengwen, and Taimali River basins in southern Taiwan, and on the disaster impacts and damages in these river basins due to Typhoon Morakot in 2009. The data was offered by the National Science and Technology Center for Disaster Reduction, Taiwan, as well as collected from the National Land Use Investigation, official census statistics and questionnaire surveys. 3. Results We use an MCDA to create a composite vulnerability index, and this index is incorporated into a GIS analysis to demonstrate the results of integrated vulnerability assessment throughout the river basins. Results of the vulnerability assessment indicate that the most vulnerable areas are almost all situated in the regions of middle and upper reaches of the river basins. Through the examining of DDM, it shows that the vulnerability factors play a critical role in determining disaster damages. Findings also present that the losses and casualties caused by Typhoon Morakot increase with elevation, urban and agricultural developments, proximity to rivers, and decrease with levels of income and adaptive capacity. Finally, we propose the adaptive options for minimizing vulnerability and risk, as well as for integrated river basin governance.

Identifying treatment effect heterogeneity in clinical trials using subpopulations of events: STEPP.

PubMed

Lazar, Ann A; Bonetti, Marco; Cole, Bernard F; Yip, Wai-Ki; Gelber, Richard D

2016-04-01

Investigators conducting randomized clinical trials often explore treatment effect heterogeneity to assess whether treatment efficacy varies according to patient characteristics. Identifying heterogeneity is central to making informed personalized healthcare decisions. Treatment effect heterogeneity can be investigated using subpopulation treatment effect pattern plot (STEPP), a non-parametric graphical approach that constructs overlapping patient subpopulations with varying values of a characteristic. Procedures for statistical testing using subpopulation treatment effect pattern plot when the endpoint of interest is survival remain an area of active investigation. A STEPP analysis was used to explore patterns of absolute and relative treatment effects for varying levels of a breast cancer biomarker, Ki-67, in the phase III Breast International Group 1-98 randomized clinical trial, comparing letrozole to tamoxifen as adjuvant therapy for postmenopausal women with hormone receptor-positive breast cancer. Absolute treatment effects were measured by differences in 4-year cumulative incidence of breast cancer recurrence, while relative effects were measured by the subdistribution hazard ratio in the presence of competing risks using O-E (observed-minus-expected) methodology, an intuitive non-parametric method. While estimation of hazard ratio values based on O-E methodology has been shown, a similar development for the subdistribution hazard ratio has not. Furthermore, we observed that the subpopulation treatment effect pattern plot analysis may not produce results, even with 100 patients within each subpopulation. After further investigation through simulation studies, we observed inflation of the type I error rate of the traditional test statistic and sometimes singular variance-covariance matrix estimates that may lead to results not being produced. This is due to the lack of sufficient number of events within the subpopulations, which we refer to as instability of the subpopulation treatment effect pattern plot analysis. We introduce methodology designed to improve stability of the subpopulation treatment effect pattern plot analysis and generalize O-E methodology to the competing risks setting. Simulation studies were designed to assess the type I error rate of the tests for a variety of treatment effect measures, including subdistribution hazard ratio based on O-E estimation. This subpopulation treatment effect pattern plot methodology and standard regression modeling were used to evaluate heterogeneity of Ki-67 in the Breast International Group 1-98 randomized clinical trial. We introduce methodology that generalizes O-E methodology to the competing risks setting and that improves stability of the STEPP analysis by pre-specifying the number of events across subpopulations while controlling the type I error rate. The subpopulation treatment effect pattern plot analysis of the Breast International Group 1-98 randomized clinical trial showed that patients with high Ki-67 percentages may benefit most from letrozole, while heterogeneity was not detected using standard regression modeling. The STEPP methodology can be used to study complex patterns of treatment effect heterogeneity, as illustrated in the Breast International Group 1-98 randomized clinical trial. For the subpopulation treatment effect pattern plot analysis, we recommend a minimum of 20 events within each subpopulation. © The Author(s) 2015.

Smallholder Food and Water Security in the Face of Climatic Stress and the Coffee Leaf Rust: Lessons from Nicaragua

NASA Astrophysics Data System (ADS)

Stewart, I. T.; Bacon, C. M.; Sundstrom, W.

2015-12-01

Smallholder farmers in Nicaragua and throughout much of Central America preserve forest biodiversity and contribute to the sustainable production of coffee and other crops while, paradoxically, they themselves must cope with recurring periods of seasonal hunger. Smallholder food and water security in the region is affected by hurricanes, periodic drought events, climatic changes, an on-going outbreak of the coffee leaf rust, and fluctuations in food prices. Using regression analysis, our research examines what factors strengthened resilience to these hazards at the household level over the 1981 - 2014 time period. To this end, we integrate qualitative research on coping responses and local institutions, a participatory survey of 368 households, and an analysis of hydro-climatic data. Our results indicate that coping responses to the coffee leaf rust outbreak and the 2014 drought are comparable in severity to those used to endure Hurricane Mitch in 1998, and a severe 2009 drought. Higher smallholder resilience to stresses affecting food and water security is associated with larger farms, off-farm employment, more on-farm food production, higher numbers of fruit trees, and greater coffee harvests. Households that reported more severe coping responses to hazards earlier in the study period tended to be more strongly impacted by later hazards and reported generally greater seasonal hunger. Affiliation with local farmer-to-farmer institutions prioritizing either subsistence-oriented production or sales to international fair-trade markets did not correlate strongly with coping responses; however, subsistence-oriented institutions promote several resilience-enhancing practices. Lessons learned by adapting to past hazards may be used to develop adaptation and mitigation strategies for smallholders under continued climate variability and change.

Hazard Analysis Guidelines for Transit Projects

DOT National Transportation Integrated Search

2000-01-01

These hazard analysis guidelines discuss safety critical systems and subsystems, types of hazard analyses, when hazard analyses should be performed, and the hazard analysis philosophy. These guidelines are published by FTA to assist the transit indus...

Defining and Measuring Coastal Vulnerability and Resilience to Natural Hazards

NASA Astrophysics Data System (ADS)

Becker, M. K.; Hoagland, P.

2014-12-01

Accounting for an estimated 23 percent of the world's population, coastal communities face many types of natural hazards. In particular, they may be vulnerable to the effects of tropical cyclones, flooding due to tsunamis or storm surges, erosion, saltwater intrusion, and subsidence. These coastal hazards are further exacerbated by population growth and climate change. There is a lack of consensus in the literature about what constitutes vulnerability (negative impacts) and resilience (recovery from negative impacts) and how to measure these phenomena. While some important work has focused on the long-term effects of coastal hazards on economic growth, little has been done to understand, in quantitative terms, the extent to which coastal communities may be vulnerable to such hazards and, if so, whether they can be resilient. We surveyed nine indicators of human well-being in order to determine their potential suitability as measures of coastal vulnerability or resilience. Some measures, such as the Gross Domestic Product, the Human Development Index, and the Gini coefficient, comprise economic or distributional indicators of human welfare; others, such as the Social Vulnerability Index, are more complex and difficult to interpret. We selected per capita personal income as the most viable indicator, due largely to its simplicity and its availability over several decades. We used it to examine human community vulnerability and resilience to a specific coastal hazard—significant storm surges from major coastal hurricanes—in several US coastal metropolitan areas. We compiled data on per capita personal income from the US Bureau of Economic Analysis for 15 to 20 years prior and subsequent to four major hurricanes: Hugo, which hit the Charleston, South Carolina, metropolitan area in 1989; Bob, Cape Cod, Massachusetts, in 1991; Andrew, Miami, Florida, in 1992; and Opal, Pensacola, Florida, in 1995. Intervention analysis using linear regression suggests that these coastal areas exhibited the full range of possible combinations of vulnerability and resilience.

Experimental demonstration of a two-phase population extinction hazard

PubMed Central

Drake, John M.; Shapiro, Jeff; Griffen, Blaine D.

2011-01-01

Population extinction is a fundamental biological process with applications to ecology, epidemiology, immunology, conservation biology and genetics. Although a monotonic relationship between initial population size and mean extinction time is predicted by virtually all theoretical models, attempts at empirical demonstration have been equivocal. We suggest that this anomaly is best explained with reference to the transient properties of ensembles of populations. Specifically, we submit that under experimental conditions, many populations escape their initially vulnerable state to reach quasi-stationarity, where effects of initial conditions are erased. Thus, extinction of populations initialized far from quasi-stationarity may be exposed to a two-phase extinction hazard. An empirical prediction of this theory is that the fit Cox proportional hazards regression model for the observed survival time distribution of a group of populations will be shown to violate the proportional hazards assumption early in the experiment, but not at later times. We report results of two experiments with the cladoceran zooplankton Daphnia magna designed to exhibit this phenomenon. In one experiment, habitat size was also varied. Statistical analysis showed that in one of these experiments a transformation occurred so that very early in the experiment there existed a transient phase during which the extinction hazard was primarily owing to the initial population size, and that this was gradually replaced by a more stable quasi-stationary phase. In the second experiment, only habitat size unambiguously displayed an effect. Analysis of data pooled from both experiments suggests that the overall extinction time distribution in this system results from the mixture of extinctions during the initial rapid phase, during which the effects of initial population size can be considerable, and a longer quasi-stationary phase, during which only habitat size has an effect. These are the first results, to our knowledge, of a two-phase population extinction process. PMID:21429907

Prognostic value of human papillomavirus 16/18 genotyping in low-grade cervical lesions preceded by mildly abnormal cytology.

PubMed

Ye, Jing; Cheng, Bei; Cheng, Yi-Fan; Yao, Ye-Li; Xie, Xing; Lu, Wei-Guo; Cheng, Xiao-Dong

Histological low-grade squamous intraepithelial lesion/cervical intraepithelial neoplasia grade 1 (LSIL/CIN1) preceded by normal or mildly abnormal cytology is recommended for conservative follow-up, with no separated management. In this study, we assessed the triage value of human papillomavirus (HPV) 16/18 genotyping in 273 patients with LSIL/CIN1. HPV16/18 genotyping was performed at baseline and follow-up was at 6-monthly intervals for up to 2 years. At each follow-up, women positive for cytology or high-risk HPV (hrHPV) were referred for colposcopy. Enrollment cytology, HPV16/18 genotyping, and questionnaire-obtained factors were linked to the 2-year cumulative progression rate. Univariate and multivariate analyses were performed taking into account time-to-event with Cox proportional hazard regression. The results showed that 190 cases (69.6%) regressed, 37 (13.6%) persisted, and 46 (16.8%) progressed. HPV16/18 positivity (hazard ratio (HR), 2.708; 95% confidence interval (CI), 1.432-5.121; P=0.002) is significantly associated with higher 2-year cumulative progression rate. Sub-analysis by enrollment cytology and age restricted the positive association among patients preceded by mildly abnormal cytology and aged 30 years or older. Immediate treatment is a rational recommendation for the high-risk subgroup, when good compliance is not assured.

14 CFR 437.29 - Hazard analysis.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Hazard analysis. 437.29 Section 437.29... Documentation § 437.29 Hazard analysis. (a) An applicant must perform a hazard analysis that complies with § 437.55(a). (b) An applicant must provide to the FAA all the results of each step of the hazard analysis...

14 CFR 437.29 - Hazard analysis.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Hazard analysis. 437.29 Section 437.29... Documentation § 437.29 Hazard analysis. (a) An applicant must perform a hazard analysis that complies with § 437.55(a). (b) An applicant must provide to the FAA all the results of each step of the hazard analysis...

Colorectal cancer outcomes and treatment patterns in patients too young for average-risk screening.

PubMed

Abdelsattar, Zaid M; Wong, Sandra L; Regenbogen, Scott E; Jomaa, Diana M; Hardiman, Karin M; Hendren, Samantha

2016-03-15

Although colorectal cancer (CRC) screening guidelines recommend initiating screening at age 50 years, the percentage of cancer cases in younger patients is increasing. To the authors' knowledge, the national treatment patterns and outcomes of these patients are largely unknown. The current study was a population-based, retrospective cohort study of the nationally representative Surveillance, Epidemiology, and End Results registry for patients diagnosed with CRC from 1998 through 2011. Patients were categorized as being younger or older than the recommended screening age. Differences with regard to stage of disease at diagnosis, patterns of therapy, and disease-specific survival were compared between age groups using multinomial regression, multiple regression, Cox proportional hazards regression, and Weibull survival analysis. Of 258,024 patients with CRC, 37,847 (15%) were aged <50 years. Young patients were more likely to present with regional (relative risk ratio, 1.3; P<.001) or distant (relative risk ratio, 1.5; P<.001) disease. Patients with CRC with distant metastasis in the younger age group were more likely to receive surgical therapy for their primary tumor (adjusted probability: 72% vs 63%; P<.001), and radiotherapy also was more likely in younger patients with CRC (adjusted probability: 53% vs 48%; P<.001). Patients younger than the recommended screening age had better overall disease-specific survival (hazards ratio, 0.77; P<.001), despite a larger percentage of these individuals presenting with advanced disease. Patients with CRC diagnosed at age <50 years are more likely to present with advanced-stage disease. However, they receive more aggressive therapy and achieve longer disease-specific survival, despite the greater percentage of patients with advanced-stage disease. These findings suggest the need for improved risk assessment and screening decisions for younger adults. © 2016 American Cancer Society.

Role of Adjuvant Chemotherapy in ypT0-2N0 Patients Treated with Preoperative Chemoradiation Therapy and Radical Resection for Rectal Cancer.

PubMed

Park, In Ja; Kim, Dae Yong; Kim, Hee Cheol; Kim, Nam Kyu; Kim, Hyeong-Rok; Kang, Sung-Bum; Choi, Gyu-Seog; Lee, Kang Young; Kim, Seon-Hahn; Oh, Seung Taek; Lim, Seok-Byung; Kim, Jin Cheon; Oh, Jae Hwan; Kim, Sun Young; Lee, Woo Yong; Lee, Jung Bok; Yu, Chang Sik

2015-07-01

To explore the role of adjuvant chemotherapy for patients with ypT0-2N0 rectal cancer treated by preoperative chemoradiation therapy (PCRT) and radical resection. A national consortium of 10 institutions was formed, and patients with ypT0-2N0 mid- and low-rectal cancer after PCRT and radical resection from 2004 to 2009 were included. Patients were categorized into 2 groups according to receipt of additional adjuvant chemotherapy: Adj CTx (+) versus Adj CTx (-). Propensity scores were calculated and used to perform matched and adjusted analyses comparing relapse-free survival (RFS) between treatment groups while controlling for potential confounding. A total of 1016 patients, who met the selection criteria, were evaluated. Of these, 106 (10.4%) did not receive adjuvant chemotherapy. There was no overall improvement in 5-year RFS as a result of adjuvant chemotherapy [91.6% for Adj CTx (+) vs 87.5% for Adj CTx (-), P=.18]. There were no differences in 5-year local recurrence and distant metastasis rate between the 2 groups. In patients who show moderate, minimal, or no regression in tumor regression grade, however, possible association of adjuvant chemotherapy with RFS would be considered (hazard ratio 0.35; 95% confidence interval 0.14-0.88; P=.03). Cox regression analysis after propensity score matching failed to show that addition of adjuvant chemotherapy was associated with improved RFS (hazard ratio 0.81; 95% confidence interval 0.39-1.70; P=.58). Adjuvant chemotherapy seemed to not influence the RFS of patients with ypT0-2N0 rectal cancer after PCRT followed by radical resection. Thus, the addition of adjuvant chemotherapy needs to be weighed against its oncologic benefits. Copyright © 2015 Elsevier Inc. All rights reserved.

[The effect of occupational stress on depression symptoms among 244 policemen in a city].

PubMed

Gu, Guizhen; Yu, Shanfa; Wu, Hui; Zhou, Wenhui

2015-10-01

To explore the influence of occupational stress related factors on depression symptoms among 244 policemen in a city in China. In May 2011, 287 policemen from a city public security bureau were recruited to this survey by cluster sampling method. We deleted questionnaires which include missing variables on demographic characteristics and factors associated with occupational stress questionnaires which include over 3 missing items. 244 policemen were included in this study. Depression symptoms and occupational stressors were measured using Chinese version of depression self-reported questionnaire, job content questionnaire, Chinese version of effort-reward imbalances questionnaire, job hazard scale and occupational stress inventory. Depression symptom scores and the relationship between the variables and occupational stress were analyzed by Spearman correlation analysis and multiple regression analysis. The Median (P25-P75) of depression symptom scores of all respondents was 16.50 (11.00-25.00). 144 were policemen with no depression symptoms and 100 were with depression symptoms. The median (P25-P75) of depression symptoms scores among policemen with length of serves <10, 10-19, 20-29 and ≥30 was 17.00 (8.00-26.00), 16.00 (11.00-24.50), 19.00 (12.00-27.00), and 12.00 (6.25-15.00), respectively. The difference of scores was significant among length of serves groups (χ2=9.52, P=0.023). The scores of psychological demands, sleep disorder, daily life stress and negative affectivity among policemen with depression symptoms were 17.00 (8.00-26.00), 16.00 (11.00-24.50), 19.00 (12.00-27.00), and 12.00 (6.25-15.00), respectively, which were higher than those with no depression symptoms (24.00 (22.00-25.00), 8.00 (5.00-13.00), 8.00 (6.00-10.00), 1.00 (0-2.75)), and the differences were significant (Z=3.82, 5.39, 5.15, 6.41, P<0.001). Spearman correlation analysis revealed that depression symptoms score was positively related to sleep disorder, commitment effort, psychological demands, daily life stress, negative affectivity and job hazards scores. Correlations coefficient were 0.44, 0.28, 0.28, 0.33, 0.38, 0.44, and 0.38, respectively (P<0.001). Multiple linear regression analysis indicated that self-esteem, daily life stress and negative affectivity had bigger contribution on the depression symptoms scores. The standard regression coefficient was -0.46, 0.19 and 0.13, respectively (P<0.001, P=0.001, P=0.030). Sleep disorder, commitment effort, psychological demands, daily life stress, negative affectivity and job hazards scores were the inducement of depression symptoms for policemen. To reduce the daily life stress, negative affectivity and improve the quality of sleep, add to self-esteem, reward and social support have positive effects on reducing the occurrence of depressive symptoms for police.

Accounting for individual differences and timing of events: estimating the effect of treatment on criminal convictions in heroin users

PubMed Central

2014-01-01

Background The reduction of crime is an important outcome of opioid maintenance treatment (OMT). Criminal intensity and treatment regimes vary among OMT patients, but this is rarely adjusted for in statistical analyses, which tend to focus on cohort incidence rates and rate ratios. The purpose of this work was to estimate the relationship between treatment and criminal convictions among OMT patients, adjusting for individual covariate information and timing of events, fitting time-to-event regression models of increasing complexity. Methods National criminal records were cross linked with treatment data on 3221 patients starting OMT in Norway 1997–2003. In addition to calculating cohort incidence rates, criminal convictions was modelled as a recurrent event dependent variable, and treatment a time-dependent covariate, in Cox proportional hazards, Aalen’s additive hazards, and semi-parametric additive hazards regression models. Both fixed and dynamic covariates were included. Results During OMT, the number of days with criminal convictions for the cohort as a whole was 61% lower than when not in treatment. OMT was associated with reduced number of days with criminal convictions in all time-to-event regression models, but the hazard ratio (95% CI) was strongly attenuated when adjusting for covariates; from 0.40 (0.35, 0.45) in a univariate model to 0.79 (0.72, 0.87) in a fully adjusted model. The hazard was lower for females and decreasing with older age, while increasing with high numbers of criminal convictions prior to application to OMT (all p < 0.001). The strongest predictors were level of criminal activity prior to entering into OMT, and having a recent criminal conviction (both p < 0.001). The effect of several predictors was significantly time-varying with their effects diminishing over time. Conclusions Analyzing complex observational data regarding to fixed factors only overlooks important temporal information, and naïve cohort level incidence rates might result in biased estimates of the effect of interventions. Applying time-to-event regression models, properly adjusting for individual covariate information and timing of various events, allows for more precise and reliable effect estimates, as well as painting a more nuanced picture that can aid health care professionals and policy makers. PMID:24886472

Lunar mission safety and rescue: Hazards analysis and safety requirements

NASA Technical Reports Server (NTRS)

1971-01-01

The results are presented of the hazards analysis which was concerned only with hazards to personnel and not with loss of equipment or property. Hazards characterization includes the definition of a hazard, the hazard levels, and the hazard groups. The analysis methodology is described in detail. The methodology was used to prepare the top level functional flow diagrams, to perform the first level hazards assessment, and to develop a list of conditions and situations requiring individual hazard studies. The 39 individual hazard study results are presented in total.

Bim may be a poor prognostic biomarker in breast cancer patients especially in those with luminal A tumors.

PubMed

Maimaiti, Yusufu; Dong, Lingling; Aili, Aikebaier; Maimaitiaili, Maimaitiaili; Huang, Tao; Abudureyimu, Kelimu

2017-07-04

Bcl-2 interacting mediator of cell death (Bim) appears to have contradictory roles in cancer. It is uncertain whether Bim show prognostic significance in patients with breast cancer. To investigate the correlation between Bim expression and clinicopathological characteristics of breast cancer and to evaluate Bim's effect on overall survival (OS). We used immunohistochemistry (IHC) technique to detect the expression of Bim via tissue microarray in 275 breast cancer samples, Kaplan-Meier analysis to perform survival analysis, and Cox proportional hazards regression model to explore the risk factors of breast cancer. The results revealed that Bim expression was significantly correlated with age, estrogen receptor (ER) and/or progesterone receptor (PR), human epidermal growth factor receptor (HER2) and Ki67 expression (P< 0.05). Bim expression was significantly different in the four molecular subtypes (P= 0.000). Survival analysis showed that Bim positive expression contributed to a shorter OS (P= 0.034), especially in patients with luminal A tumors (P= 0.039). Univariate and multivariate regression analysis showed that Bim was an independent prognostic factor for breast cancer (P< 0.05). Bim may serve as an effective predictive factor for lower OS in breast cancer patients, especially in those with luminal A tumors.

Determining delayed admission to intensive care unit for mechanically ventilated patients in the emergency department.

PubMed

Hung, Shih-Chiang; Kung, Chia-Te; Hung, Chih-Wei; Liu, Ber-Ming; Liu, Jien-Wei; Chew, Ghee; Chuang, Hung-Yi; Lee, Wen-Huei; Lee, Tzu-Chi

2014-08-23

The adverse effects of delayed admission to the intensive care unit (ICU) have been recognized in previous studies. However, the definitions of delayed admission varies across studies. This study proposed a model to define "delayed admission", and explored the effect of ICU-waiting time on patients' outcome. This retrospective cohort study included non-traumatic adult patients on mechanical ventilation in the emergency department (ED), from July 2009 to June 2010. The primary outcomes measures were 21-ventilator-day mortality and prolonged hospital stays (over 30 days). Models of Cox regression and logistic regression were used for multivariate analysis. The non-delayed ICU-waiting was defined as a period in which the time effect on mortality was not statistically significant in a Cox regression model. To identify a suitable cut-off point between "delayed" and "non-delayed", subsets from the overall data were made based on ICU-waiting time and the hazard ratio of ICU-waiting hour in each subset was iteratively calculated. The cut-off time was then used to evaluate the impact of delayed ICU admission on mortality and prolonged length of hospital stay. The final analysis included 1,242 patients. The time effect on mortality emerged after 4 hours, thus we deduced ICU-waiting time in ED > 4 hours as delayed. By logistic regression analysis, delayed ICU admission affected the outcomes of 21 ventilator-days mortality and prolonged hospital stay, with odds ratio of 1.41 (95% confidence interval, 1.05 to 1.89) and 1.56 (95% confidence interval, 1.07 to 2.27) respectively. For patients on mechanical ventilation at the ED, delayed ICU admission is associated with higher probability of mortality and additional resource expenditure. A benchmark waiting time of no more than 4 hours for ICU admission is recommended.

21 CFR 123.6 - Hazard analysis and Hazard Analysis Critical Control Point (HACCP) plan.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Hazard analysis and Hazard Analysis Critical Control Point (HACCP) plan. 123.6 Section 123.6 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... processor shall have and implement a written HACCP plan whenever a hazard analysis reveals one or more food...

21 CFR 123.6 - Hazard analysis and Hazard Analysis Critical Control Point (HACCP) plan.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Hazard analysis and Hazard Analysis Critical Control Point (HACCP) plan. 123.6 Section 123.6 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... processor shall have and implement a written HACCP plan whenever a hazard analysis reveals one or more food...

Long-term outcomes in patients with rheumatologic disorders undergoing percutaneous coronary intervention: a BAsel Stent Kosten-Effektivitäts Trial-PROspective Validation Examination (BASKET-PROVE) sub-study.

PubMed

Nochioka, Kotaro; Biering-Sørensen, Tor; Hansen, Kim Wadt; Sørensen, Rikke; Pedersen, Sune; Jørgensen, Peter Godsk; Iversen, Allan; Shimokawa, Hiroaki; Jeger, Raban; Kaiser, Christoph; Pfisterer, Matthias; Galatius, Søren

2017-12-01

Rheumatologic disorders are characterised by inflammation and an increased risk of coronary artery disease (CAD). However, the association between rheumatologic disorders and long-term prognosis in CAD patients undergoing percutaneous coronary intervention (PCI) is unknown. Thus, we aimed to examine the association between rheumatologic disorders and long-term prognosis in CAD patients undergoing PCI. A post-hoc analysis was performed in 4605 patients (age: 63.3 ± 11.0 years; male: 76.6%) with ST-segment elevation myocardial infarction (STEMI; n = 1396), non-STEMI ( n = 1541), and stable CAD ( n = 1668) from the all-comer stent trials, the BAsel Stent Kosten-Effektivitäts Trial-PROspective Validation Examination (BASKET-PROVE) I and II trials. We evaluated the association between rheumatologic disorders and 2-year major adverse cardiac events (MACEs; cardiac death, nonfatal myocardial infarction (MI), and target vessel revascularisation (TVR)) by Cox regression analysis. Patients with rheumatologic disorders ( n = 197) were older, more often female, had a higher prevalence of renal disease, multi-vessel coronary disease, and bifurcation lesions, and had longer total stent lengths. During the 2-year follow-up, the MACE rate was 8.6% in the total cohort. After adjustment for potential confounders, rheumatologic disorders were associated with MACEs in the total cohort (adjusted hazard ratio: 1.55; 95% confidence interval (CI): 1.04-2.31) driven by the STEMI subgroup (adjusted hazard ratio: 2.38; 95% CI: 1.26-4.51). In all patients, rheumatologic disorders were associated with all-cause death (adjusted hazard ratio: 2.05; 95% CI: 1.14-3.70), cardiac death (adjusted hazard ratio: 2.63; 95% CI: 1.27-5.43), and non-fatal MI (adjusted hazard ratio: 2.64; 95% CI: 1.36-5.13), but not with TVR (adjusted hazard ratio: 0.81; 95% CI: 0.41-1.58). The presence of rheumatologic disorders appears to be independently associated with worse outcome in CAD patients undergoing PCI. This calls for further studies and focus on this high-risk group of patients following PCI.

Does buccal cancer have worse prognosis than other oral cavity cancers?

PubMed

Camilon, P Ryan; Stokes, William A; Fuller, Colin W; Nguyen, Shaun A; Lentsch, Eric J

2014-06-01

To determine whether buccal squamous cell carcinoma has worse overall survival (OS) and disease-specific survival (DSS) than cancers in the rest of the oral cavity. Retrospective analysis of a large population database. We began with a Kaplan-Meier analysis of OS and DSS for buccal versus nonbuccal tumors with unmatched data, followed by an analysis of cases matched for race, age at diagnosis, stage at diagnosis, and treatment modality. This was supported by a univariate Cox regression comparing buccal cancer to nonbuccal cancer, followed by a multivariate Cox regression that included all significant variables studied. With unmatched data, buccal cancer had significantly lesser OS and DSS values than cancers in the rest of the oral cavity (P < .001). After case matching, the differences between OS and DSS for buccal cancer versus nonbuccal oral cancer were no longer significant. Univariate Cox regression models with respect to OS and DSS showed a significant difference between buccal cancer and nonbuccal cancer. However, with multivariate analysis, buccal hazard ratios for OS and DSS were not significant. With the largest series of buccal carcinoma to date, our study concludes that the OS and DSS of buccal cancer are similar to those of cancers in other oral cavity sites once age at diagnosis, tumor stage, treatment, and race are taken into consideration. The previously perceived poor prognosis of buccal carcinoma may be due to variations in tumor presentation, such as later stage and older patient age. 2b. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

The predictive value of mean serum uric acid levels for developing prediabetes.

PubMed

Zhang, Qing; Bao, Xue; Meng, Ge; Liu, Li; Wu, Hongmei; Du, Huanmin; Shi, Hongbin; Xia, Yang; Guo, Xiaoyan; Liu, Xing; Li, Chunlei; Su, Qian; Gu, Yeqing; Fang, Liyun; Yu, Fei; Yang, Huijun; Yu, Bin; Sun, Shaomei; Wang, Xing; Zhou, Ming; Jia, Qiyu; Zhao, Honglin; Huang, Guowei; Song, Kun; Niu, Kaijun

2016-08-01

We aimed to assess the predictive value of mean serum uric acid (SUA) levels for incident prediabetes. Normoglycemic adults (n=39,353) were followed for a median of 3.0years. Prediabetes is defined as impaired fasting glucose (IFG), impaired glucose tolerance (IGT), or impaired HbA1c (IA1c), based on the American Diabetes Association criteria. Serum SUA levels were measured annually. Four diagnostic strategies were used to detect prediabetes in four separate analyses (Analysis 1: IFG. Analysis 2: IFG+IGT. Analysis 3: IFG+IA1c. Analysis 4: IFG+IGT+IA1c). Cox proportional hazards regression models were used to assess the relationship between SUA quintiles and prediabetes. C-statistic was additionally used in the final analysis to assess the accuracy of predictions based upon baseline SUA and mean SUA, respectively. After adjustment for potential confounders, the hazard ratios (95% confidence interval) of prediabetes for the highest versus lowest quintile of mean SUA were 1.22 (1.10, 1.36) in analysis 1; 1.59 (1.23, 2.05) in analysis 2; 1.62 (1.34, 1.95) in analysis 3 and 1.67 (1.31, 2.13) in analysis 4. In contrast, for baseline SUA, significance was only reached in analyses 3 and 4. Moreover, compared with baseline SUA, mean SUA value was associated with a significant increase in the C-statistic (P<0.001). Mean SUA value was strongly and positively related to prediabetes risk, and showed better predictive ability for prediabetes than baseline SUA. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Patients started on hemodialysis with tunneled dialysis catheter have similar survival after arteriovenous fistula and arteriovenous graft creation.

PubMed

Yuo, Theodore H; Chaer, Rabih A; Dillavou, Ellen D; Leers, Steven A; Makaroun, Michel S

2015-12-01

Current guidelines suggest that arteriovenous fistula (AVF) is associated with survival advantage over arteriovenous graft (AVG). However, AVFs often require months to become functional, increasing tunneled dialysis catheter (TDC) use, which can erode the benefit of an AVF. We sought to compare survival in patients with end-stage renal disease after creation of an AVF or AVG in patients starting hemodialysis (HD) with a TDC and to identify patient populations that may benefit from preferential use of AVG over AVF. Using U.S. Renal Data System databases, we identified incident HD patients in 2005 through 2008 and observed them through 2008. Initial access type and clinical variables including albumin levels were assessed using U.S. Renal Data System data collection forms. Attempts at AVF and AVG creation in patients who started HD through a TDC were identified by Current Procedural Terminology codes. We accounted for the effect of changes in access type by truncating follow-up when an additional AVF or AVG was performed. Survival curves were then constructed, and log-rank tests were used for pairwise survival comparisons, stratified by age. Multivariate analysis was performed with Cox proportional hazards regressions; variables were chosen using stepwise elimination. An interaction of access type and albumin level was detected, and Cox models using differing thresholds for albumin level were constructed. The primary outcome was survival. Among the 138,245 patients who started with a TDC and had complete records amenable for analysis, 22.8% underwent AVF creation (mean age ± standard deviation, 68.9 ± 12.5 years; 27.8% mortality at 1 year) and 7.6% underwent AVG placement (70.2 ± 12.0 years; 28.2% mortality) within 3 months of HD initiation; 69.6% remained with a TDC (63.2 ± 15.4 years; 33.8% mortality). In adjusted Cox proportional hazards regression, AVF creation is equivalent to AVG placement in terms of survival (hazard ratio [HR], 0.98; 95% confidence interval [CI], 0.93-1.02; P = .349). AVG placement is superior to continued TDC use (HR, 1.54; 95% CI, 1.48-1.61; P < .001). In patients older than 80 years with albumin levels >4.0 g/dL, AVF creation is associated with higher mortality hazard compared with AVG creation (HR, 1.22; 95% CI, 1.04-1.43; P = .013). For patients who start HD through a TDC, placement of an AVF and AVG is associated with similar mortality hazard. Further study is necessary to determine the ideal access for patients in whom the survival advantage of an AVF over an AVG is uncertain. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Demographic and cardiovascular risk factors modify association of fasting insulin with incident coronary heart disease and ischemic stroke (from the Atherosclerosis Risk In Communities Study).

PubMed

Rasmussen-Torvik, Laura J; Yatsuya, Hiroshi; Selvin, Elizabeth; Alonso, Alvaro; Folsom, Aaron R

2010-05-15

Previous studies have reported an association between circulating insulin and incident cardiovascular disease, but limited knowledge is available on the association across subgroups. We examined the associations of fasting insulin with incident coronary heart disease (CHD) and ischemic stroke in multiple subgroups of a biracial, middle-age cohort. A total of 12,323 subjects were included in the analysis. The incidence of CHD (n = 960) and ischemic stroke (n = 445) through 2005 was determined through annual interviews, repeat examinations, and community surveillance. Serum insulin was measured at baseline. Cox regression analysis was used to estimate the hazard ratios by quintile of fasting insulin at baseline and to determine the significance of effect modification. In the minimally adjusted models (age, gender, race, and field center), the baseline fasting insulin quintile was positively associated with both incident CHD (hazard ratio per quintile insulin = 1.12, p-trend <0.0001) and ischemic stroke (hazard ratio per quintile insulin = 1.11, p = 0.0018). The adjustment for high-density lipoprotein completely attenuated the association of insulin with CHD but not with stroke. The associations of insulin with CHD were stronger in nonsmokers (p-interaction = 0.018) and in those without hypertension (p-interaction = 0.0087). The associations of insulin with stroke were stronger in women (p-interaction = 0.037), whites (compared to blacks; p-interaction = 0.036), and those without hypertension (p-interaction = 0.0027). Copyright 2010 Elsevier Inc. All rights reserved.

A ghrelin gene variant may predict crossover rate from restricting-type anorexia nervosa to other phenotypes of eating disorders: a retrospective survival analysis.

PubMed

Ando, Tetsuya; Komaki, Gen; Nishimura, Hiroki; Naruo, Tetsuro; Okabe, Kenjiro; Kawai, Keisuke; Takii, Masato; Oka, Takakazu; Kodama, Naoki; Nakamoto, Chiemi; Ishikawa, Toshio; Suzuki-Hotta, Mari; Minatozaki, Kazunori; Yamaguchi, Chikara; Nishizono-Maher, Aya; Kono, Masaki; Kajiwara, Sohei; Suematsu, Hiroyuki; Tomita, Yuichiro; Ebana, Shoichi; Okamoto, Yuri; Nagata, Katsutaro; Nakai, Yoshikatsu; Koide, Masanori; Kobayashi, Nobuyuki; Kurokawa, Nobuo; Nagata, Toshihiko; Kiriike, Nobuo; Takenaka, Yoshito; Nagamine, Kiyohide; Ookuma, Kazuyoshi; Murata, Shiho

2010-08-01

Patients with anorexia nervosa restricting type (AN-R) often develop bulimic symptoms and crossover to AN-binge eating/purging type (AN-BP), or to bulimia nervosa (BN). We have reported earlier that genetic variants of an orexigenic peptide ghrelin are associated with BN. Here, the relationship between a ghrelin gene variant and the rate of change from AN-R to other phenotypes of eating disorders (EDs) was investigated. Participants were 165 patients with ED, initially diagnosed as AN-R. The dates of their AN-R onset and changes in diagnosis to other subtypes of ED were investigated retrospectively. Ghrelin gene 3056 T-->C SNP (single nucleotide polymorphism) was genotyped. Probability and hazard ratios were analyzed using life table analysis and Cox's proportional hazard regression model, in which the starting point was the time of AN-R onset and the outcome events were the time of (i) onset of binge eating, that is, when patients changed to binge eating AN and BN and (ii) recovery of normal weight, that is, when patients changed to BN or remission. Patients with the TT genotype at 3056 T-->C had a higher probability and hazard ratio for recovery of normal weight. The ghrelin SNP was not related with the onset of binge eating. The 3056 T-->C SNP of the ghrelin gene is related to the probability and the rate of recovery of normal body weight from restricting-type AN.

An epigenetic signature of adhesion molecules predicts poor prognosis of ovarian cancer patients

PubMed Central

Chang, Ping-Ying; Liao, Yu-Ping; Wang, Hui-Chen; Chen, Yu-Chih; Huang, Rui-Lan; Wang, Yu-Chi; Yuan, Chiou-Chung; Lai, Hung-Cheng

2017-01-01

DNA methylation is a promising biomarker for cancer. The epigenetic effects of cell adhesion molecules may affect the therapeutic outcome and the present study examined their effects on survival in ovarian cancer. We integrated methylomics and genomics datasets in The Cancer Genome Atlas (n = 391) and identified 106 highly methylated adhesion-related genes in ovarian cancer tissues. Univariate analysis revealed the methylation status of eight genes related to progression-free survival. In multivariate Cox regression analysis, four highly methylated genes (CD97, CTNNA1, DLC1, HAPLN2) and three genes (LAMA4, LPP, MFAP4) with low methylation were significantly associated with poor progression-free survival. Low methylation of VTN was an independent poor prognostic factor for overall survival after adjustment for age and stage. Patients who carried any two of CTNNA1, DLC1 or MFAP4 were significantly associated with poor progression-free survival (hazard ratio: 1.59; 95% confidence interval: 1.23, 2.05). This prognostic methylation signature was validated in a methylomics dataset generated in our lab (n = 37, hazard ratio: 16.64; 95% confidence interval: 2.68, 103.14) and in another from the Australian Ovarian Cancer Study (n = 91, hazard ratio: 2.43; 95% confidence interval: 1.11, 5.36). Epigenetics of cell adhesion molecules is related to ovarian cancer prognosis. A more comprehensive methylomics of cell adhesion molecules is needed and may advance personalized treatment with adhesion molecule-related drugs. PMID:28881822

Percentage of Positive Biopsy Cores: A Better Risk Stratification Model for Prostate Cancer?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang Jiayi; Vicini, Frank A.; Williams, Scott G.

2012-07-15

Purpose: To assess the prognostic value of the percentage of positive biopsy cores (PPC) and perineural invasion in predicting the clinical outcomes after radiotherapy (RT) for prostate cancer and to explore the possibilities to improve on existing risk-stratification models. Methods and Materials: Between 1993 and 2004, 1,056 patients with clinical Stage T1c-T3N0M0 prostate cancer, who had four or more biopsy cores sampled and complete biopsy core data available, were treated with external beam RT, with or without a high-dose-rate brachytherapy boost at William Beaumont Hospital. The median follow-up was 7.6 years. Multivariate Cox regression analysis was performed with PPC, Gleasonmore » score, pretreatment prostate-specific antigen, T stage, PNI, radiation dose, androgen deprivation, age, prostate-specific antigen frequency, and follow-up duration. A new risk stratification (PPC classification) was empirically devised to incorporate PPC and replace the T stage. Results: On multivariate Cox regression analysis, the PPC was an independent predictor of distant metastasis, cause-specific survival, and overall survival (all p < .05). A PPC >50% was associated with significantly greater distant metastasis (hazard ratio, 4.01; 95% confidence interval, 1.86-8.61), and its independent predictive value remained significant with or without androgen deprivation therapy (all p < .05). In contrast, PNI and T stage were only predictive for locoregional recurrence. Combining the PPC ({<=}50% vs. >50%) with National Comprehensive Cancer Network risk stratification demonstrated added prognostic value of distant metastasis for the intermediate-risk (hazard ratio, 5.44; 95% confidence interval, 1.78-16.6) and high-risk (hazard ratio, 4.39; 95% confidence interval, 1.70-11.3) groups, regardless of the use of androgen deprivation and high-dose RT (all p < .05). The proposed PPC classification appears to provide improved stratification of the clinical outcomes relative to the National Comprehensive Cancer Network classification. Conclusions: The PPC is an independent and powerful predictor of clinical outcomes of prostate cancer after RT. A risk model replacing T stage with the PPC to reduce subjectivity demonstrated potentially improved stratification.« less

Neoadjuvant Chemotherapy versus Chemoradiation Prior to Esophagectomy: Impact on Rate of Complete Pathologic Response and Survival in Esophageal Cancer Patients.

PubMed

Samson, Pamela; Robinson, Clifford; Bradley, Jeffrey; Lockhart, A Craig; Puri, Varun; Broderick, Stephen; Kreisel, Daniel; Krupnick, A Sasha; Patterson, G Alexander; Meyers, Bryan; Crabtree, Traves

2016-12-01

The aim of this study was to evaluate differences in pathologic complete response (pCR) rates and overall survival among patients receiving either neoadjuvant chemotherapy or chemoradiation before esophagectomy for locally advanced esophageal cancer. Patients with esophageal cancer receiving either neoadjuvant chemotherapy or chemoradiation before esophagectomy were identified using the National Cancer Database. Univariate analysis compared patient, tumor, and postoperative outcome characteristics. Logistic regression was performed to identify variables associated with achieving pCR. Kaplan-Meier analysis was performed to compare overall median survival by neoadjuvant therapy type and pCR status. Finally, a Cox proportional hazards model was fitted to identify variables associated with increased mortality hazard. From 2006 to 2012, a total of 916 of 7338 of patients (12.5%) received neoadjuvant chemotherapy whereas 6422 (87.5%) received neoadjuvant chemoradiation. Patients who received neoadjuvant chemoradiation were more likely to achieve a pCR (17.2% versus 6.4%, p < 0.001) and less likely to have positive margins (5.6% versus 11.5%, p < 0.001) than were patients who received neoadjuvant chemotherapy, with no difference in 30- or 90-day mortality. Achieving a pCR was associated with improved overall median survival (59.5 ± 4.0 months versus 30.1 ± 0.76 months for those with persistent disease, p < 0.001). On logistic regression, neoadjuvant chemoradiation therapy was independently associated with achieving a pCR (OR = 2.75, 95% confidence interval: 2.01-3.77, p < 0.001). Despite improvement in the pCR rate with neoadjuvant chemoradiation, neoadjuvant therapy type was not independently associated with long-term survival (hazard ratio = 1.12; 95% confidence interval: 0.97-1.30, p = 0.12). Although neoadjuvant chemoradiation is more successful in downstaging esophageal cancer before esophagectomy, it was not independently prognostic for improved long-term survival. Other factors affecting long-term survival among pathologic complete responders and among patients with persistent disease should be investigated to clarify this association. Copyright © 2016 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

Refusal of postoperative radiotherapy and its association with survival in head and neck cancer.

PubMed

Schwam, Zachary G; Husain, Zain; Judson, Benjamin L

2015-11-01

Administering postoperative radiotherapy (PORT) is associated with improved survival and slower disease progression in select head and neck cancer patients. Predictive factors for PORT refusal have not been described in this population. Retrospective analysis of 6127 head and neck cancer patients who received or refused PORT in the National Cancer Database (2003-2006) was performed. Statistical analysis included Chi-square, multivariable logistic regression, Kaplan-Meier, and Cox proportional hazards analysis. In total, 247 patients (4.0%) refused PORT. Three-year overall survival was 62.8% versus 53.4% for those who received and refused PORT, respectively. PORT refusers were more likely to have negative nodes than those who underwent PORT (37.4% versus 20.1%, p<.001). In multivariate analysis, predictive factors for refusing PORT included living far from the treatment facility (OR 1.92), having negative nodes (OR 2.14), and Charlson score of ⩾ 2 (OR 2.14) (all p ⩽.001). PORT refusal was associated with increased mortality (hazard ratio 1.20, p=.044). A significant proportion of head and neck cancer patients refused PORT; this was associated with compromised overall survival. Predictive factors for PORT refusal included socioeconomic, demographic, and pathologic variables. Elucidating root causes of refusal may lead to interventions that improve long-term outcomes. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Flood hazard studies in Central Texas using orbital and suborbital remote sensing machinery

NASA Technical Reports Server (NTRS)

Baker, V. R.; Holz, R. K.; Patton, P. C.

1975-01-01

Central Texas is subject to infrequent, unusually intense rainstorms which cause extremely rapid runoff from drainage basins developed on the deeply dissected limestone and marl bedrock of the Edwards Plateau. One approach to flood hazard evaluation in this area is a parametric model relating flood hydrograph characteristics to quantitative geomorphic properties of the drainage basins. The preliminary model uses multiple regression techniques to predict potential peak flood discharge from basin magnitude, drainage density, and ruggedness number. After mapping small catchment networks from remote sensing imagery, input data for the model are generated by network digitization and analysis by a computer assisted routine of watershed analysis. The study evaluated the network resolution capabilities of the following data formats: (1) large-scale (1:24,000) topographic maps, employing Strahler's "method of v's," (2) standard low altitude black and white aerial photography (1:13,000 and 1:20,000 scales), (3) NASA - generated aerial infrared photography at scales ranging from 1:48,000 to 1:123,000, and (4) Skylab Earth Resources Experiment Package S-190A and S-190B sensors (1:750,000 and 1:500,000 respectively).

Professional burnout and work stress among Israeli dental assistants.

PubMed

Uziel, Nir; Meyerson, Joseph; Birenzweig, Yonatan; Eli, Ilana

2018-05-16

Professional burnout and work-related stress are known problems that have been the subject of in-depth examination among dentists. Nevertheless, these issues have not been widely studied among dental assistants. The aims of this study were threefold: to confirm the structure of a Work Stress Inventory (WSI) for Dental Assistants which was originally developed for Jordanian dental assistants (factor analysis); to evaluate work stress and burnout among Israeli dental assistants and to discover the factors predicting Israeli assistants' burnout (regression analyses). The Maslach Burnout Inventory and the WSI were distributed by mail and in person. Varimax factor analysis revealed that the items which contribute to different aspects of work stress are similar among both Jordanian and Israeli populations. Among the 299 Israeli dental assistants who completed the questionnaires, the most stressful work-related factors were income, workload, and work hazards. Eighteen percent of the participants exhibited a high to very high level of burnout. Participants exhibited a moderate level of emotional exhaustion (EE), low level of depersonalization (DP), and high level of personal accomplishment (PA). Most WSI factors were found to correlate positively with EE and DP. Linear stepwise regression analyses revealed that the best predictor of EE was the dentist‒assistant relationship, followed by workload, patient type, and salary. The best predictor of DP was patient suffering followed by dentist‒assistant relationship, years of professional experience, and work hazards. Professional stress and burnout among dental assistants are important factors that can possibly affect the wellbeing of both dental personnel and their patients. Further studies are necessary to better understand these factors in addition to the effects of personal relationships on burnout among dentists and their assistants.

Primary fascial closure with mesh reinforcement is superior to bridged mesh repair for abdominal wall reconstruction.

PubMed

Booth, Justin H; Garvey, Patrick B; Baumann, Donald P; Selber, Jesse C; Nguyen, Alexander T; Clemens, Mark W; Liu, Jun; Butler, Charles E

2013-12-01

Many surgeons believe that primary fascial closure with mesh reinforcement should be the goal of abdominal wall reconstruction (AWR), yet others have reported acceptable outcomes when mesh is used to bridge the fascial edges. It has not been clearly shown how the outcomes for these techniques differ. We hypothesized that bridged repairs result in higher hernia recurrence rates than mesh-reinforced repairs that achieve fascial coaptation. We retrospectively reviewed prospectively collected data from consecutive patients with 1 year or more of follow-up, who underwent midline AWR between 2000 and 2011 at a single center. We compared surgical outcomes between patients with bridged and mesh-reinforced fascial repairs. The primary outcomes measure was hernia recurrence. Multivariate logistic regression analysis was used to identify factors predictive of or protective for complications. We included 222 patients (195 mesh-reinforced and 27 bridged repairs) with a mean follow-up of 31.1 ± 14.2 months. The bridged repairs were associated with a significantly higher risk of hernia recurrence (56% vs 8%; hazard ratio [HR] 9.5; p < 0.001) and a higher overall complication rate (74% vs 32%; odds ratio [OR] 3.9; p < 0.001). The interval to recurrence was more than 9 times shorter in the bridged group (HR 9.5; p < 0.001). Multivariate Cox proportional hazard regression analysis identified bridged repair and defect width > 15 cm to be independent predictors of hernia recurrence (HR 7.3; p < 0.001 and HR 2.5; p = 0.028, respectively). Mesh-reinforced AWRs with primary fascial coaptation resulted in fewer hernia recurrences and fewer overall complications than bridged repairs. Surgeons should make every effort to achieve primary fascial coaptation to reduce complications. Published by Elsevier Inc.

Risk Factors for Upper Gastrointestinal Bleeding in Patients Taking Selective COX-2 Inhibitors: A Nationwide Population-Based Cohort Study.

PubMed

Lin, Xi-Hsuan; Young, Shih-Hao; Luo, Jiing-Chyuan; Peng, Yen-Ling; Chen, Ping-Hsien; Lin, Chung-Chi; Chen, Wei-Ming; Hou, Ming-Chih; Lee, Fa-Yauh

2018-02-01

Cyclooxygenase-2 inhibitors (coxibs) are associated with less upper gastrointestinal bleeding (UGIB) than traditional nonsteroidal anti-inflammatory drugs (tNSAIDs). However, they also increase the risk of UGIB in high-risk patients. We aimed to identify the risk factors of UGIB in coxibs users. Retrospective cohort study. 2000-2010 National Health Insurance Research Database of Taiwan. Patients taking coxibs as the study group and patients not taking any coxibs as controls. After age, gender, and comorbidity matching by propensity score, 12,145 coxibs users and 12,145 matched controls were extracted for analysis. The primary end point was the occurrence of UGIB. Cox multivariate proportional hazard regression models were used to determine the risk factors for UGIB among all the enrollees and coxibs users. During a mean follow-up of three years, coxibs users had significantly higher incidence of UGIB than matched controls (P < 0.001, log-rank test). Cox regression analysis showed that coxibs increased risk of UGIB in all participants (hazard ratio = 1.37, 95% confidence interval = 1.19-1.55, P < 0.001). Independent risk factors for UGIB among coxibs users were age, male gender, diabetes, chronic renal disease, cirrhosis, history of peptic ulcer disease, PU bleeding (PUB), Helicobacter pylori (H. pylori) infection, and concomitant use of tNSAIDs, acetylsalicylic acid, or thienopyridines. Among coxibs users, H. pylori infection and history of PUB were especially important risk factors for UGIB. Further studies are needed to determine whether proton pump inhibitors might play a protective role in these at-risk patients. © 2017 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

The Relationship Between the Dietary Inflammatory Index and Incident Frailty: A Longitudinal Cohort Study.

PubMed

Shivappa, Nitin; Stubbs, Brendon; Hébert, James R; Cesari, Matteo; Schofield, Patricia; Soysal, Pinar; Maggi, Stefania; Veronese, Nicola

2018-01-01

Inflammation is key risk factor for several conditions in the elderly. However, the relationship between inflammation and frailty is still unclear. We investigated whether higher dietary inflammatory index (DII) scores were associated with higher incidence of frailty in a cohort of North Americans. Longitudinal, with a follow-up of 8 years. Osteoarthritis Initiative. A total of 4421 participants with, or at high risk of, knee osteoarthritis. DII scores were calculated using the validated Block Brief 2000 Food-Frequency Questionnaire and categorized into sex-specific quartiles. Frailty was defined as 2 out of 3 of the criteria of the Study of Osteoporotic Fracture study (ie, weight loss, inability to rise from a chair 5 times, and poor energy). The strength of the association between baseline DII score and incident frailty was assessed through a Cox's regression analysis, adjusted for potential baseline confounders, and reported as hazard ratios. A total of 4421 community-dwelling participants (2564 female participants; mean age: 61.3 years) without frailty at baseline were identified from the Osteoarthritis Initiative. During 8 years of follow-up, 356 individuals developed frailty (8.2%). Using Cox's regression analysis, adjusting for 11 potential confounders, participants with the highest DII score (quartile 4) had a significantly higher risk of experiencing frailty (hazard ratio 1.37; 95% confidence interval 1.01-1.89; P = .04) compared with participants with the lowest DII score (quartile 1). The association between DII score and frailty was significant only in men. Higher DII scores, indicating a more proinflammatory diet, are associated with higher incidence of frailty, particularly in men. Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Dietary Sodium Consumption Predicts Future Blood Pressure and Incident Hypertension in the Japanese Normotensive General Population.

PubMed

Takase, Hiroyuki; Sugiura, Tomonori; Kimura, Genjiro; Ohte, Nobuyuki; Dohi, Yasuaki

2015-07-29

Although there is a close relationship between dietary sodium and hypertension, the concept that persons with relatively high dietary sodium are at increased risk of developing hypertension compared with those with relatively low dietary sodium has not been studied intensively in a cohort. We conducted an observational study to investigate whether dietary sodium intake predicts future blood pressure and the onset of hypertension in the general population. Individual sodium intake was estimated by calculating 24-hour urinary sodium excretion from spot urine in 4523 normotensive participants who visited our hospital for a health checkup. After a baseline examination, they were followed for a median of 1143 days, with the end point being development of hypertension. During the follow-up period, hypertension developed in 1027 participants (22.7%). The risk of developing hypertension was higher in those with higher rather than lower sodium intake (hazard ratio 1.25, 95% CI 1.04 to 1.50). In multivariate Cox proportional hazards regression analysis, baseline sodium intake and the yearly change in sodium intake during the follow-up period (as continuous variables) correlated with the incidence of hypertension. Furthermore, both the yearly increase in sodium intake and baseline sodium intake showed significant correlations with the yearly increase in systolic blood pressure in multivariate regression analysis after adjustment for possible risk factors. Both relatively high levels of dietary sodium intake and gradual increases in dietary sodium are associated with future increases in blood pressure and the incidence of hypertension in the Japanese general population. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Is the adiposity-associated FTO gene variant related to all-cause mortality independent of adiposity? Meta-analysis of data from 169,551 Caucasian adults

PubMed Central

Mirza, S. S.; Zhao, J. H.; Chasman, D. I.; Fischer, K.; Qi, Q.; Smith, A. V.; Thinggaard, M.; Jarczok, M. N.; Nalls, M. A.; Trompet, S.; Timpson, N. J.; Schmidt, B.; Jackson, A. U.; Lyytikäinen, L. P.; Verweij, N.; Mueller-Nurasyid, M.; Vikström, M.; Marques-Vidal, P.; Wong, A.; Meidtner, K.; Middelberg, R. P.; Strawbridge, R. J.; Christiansen, L.; Kyvik, K. O.; Hamsten, A.; Jääskeläinen, T.; Tjønneland, A.; Eriksson, J. G.; Whitfield, J. B.; Boeing, H.; Hardy, R.; Vollenweider, P.; Leander, K.; Peters, A.; van der Harst, P.; Kumari, M.; Lehtimäki, T.; Meirhaeghe, A.; Tuomilehto, J.; Jöckel, K.-H.; Ben-Shlomo, Y.; Sattar, N.; Baumeister, S. E.; Smith, G. Davey; Casas, J. P.; Houston, D. K.; März, W.; Christensen, K.; Gudnason, V.; Hu, F. B.; Metspalu, A.; Ridker, P. M.; Wareham, N. J.; Loos, R. J. F.; Tiemeier, H.; Sonestedt, E.; Sørensen, T. I. A.

2015-01-01

Summary Previously, a single nucleotide polymorphism (SNP), rs9939609, in the FTO gene showed a much stronger association with all-cause mortality than expected from its association with body mass index (BMI), body fat mass index (FMI) and waist circumference (WC). This finding implies that the SNP has strong pleiotropic effects on adiposity and adiposity-independent pathological pathways that leads to increased mortality. To investigate this further, we conducted a meta-analysis of similar data from 34 longitudinal studies including 169,551 adult Caucasians among whom 27,100 died during follow-up. Linear regression showed that the minor allele of the FTO SNP was associated with greater BMI (n = 169,551; 0.32 kg m−2; 95% CI 0.28–0.32, P < 1 × 10−32), WC (n = 152,631; 0.76 cm; 0.68–0.84, P < 1 × 10−32) and FMI (n = 48,192; 0.17 kg m−2; 0.13–0.22, P = 1.0 × 10−13). Cox proportional hazard regression analyses for mortality showed that the hazards ratio (HR) for the minor allele of the FTO SNPs was 1.02 (1.00–1.04, P = 0.097), but the apparent excess risk was eliminated after adjustment for BMI and WC (HR: 1.00; 0.98–1.03, P = 0.662) and for FMI (HR: 1.00; 0.96–1.04, P = 0.932). In conclusion, this study does not support that the FTO SNP is associated with all-cause mortality independently of the adiposity phenotypes. PMID:25752329

Association between complicated liver cirrhosis and the risk of hepatocellular carcinoma in Taiwan.

PubMed

Hung, Tsung-Hsing; Liang, Chih-Ming; Hsu, Chien-Ning; Tai, Wei-Chen; Tsai, Kai-Lung; Ku, Ming-Kun; Wang, Jiunn-Wei; Tseng, Kuo-Lun; Yuan, Lan-Ting; Nguang, Seng-Howe; Yang, Shih-Cheng; Wu, Cheng-Kun; Hsu, Pin-I; Wu, Deng-Chyang; Chuah, Seng-Kee

2017-01-01

Hepatic encephalopathy, ascites, and variceal bleeding are the three major complications of cirrhosis. It is well known that cirrhosis is the most important risk factor of hepatocellular carcinoma (HCC). However, little is known about whether the severity of liver cirrhosis has an effect on the incidence of HCC. This population-based cohort study aimed to explore the association between complicated cirrhosis and HCC, and identify the risk factors of HCC in patients with complicated cirrhosis. Data of the years 1997-2011 were extracted from the National Health Insurance Research Database of Taiwan. A total of 2568 patients with complicated cirrhosis without HCC at baseline were enrolled. After propensity score matching, another 2568 patients with non-complicated cirrhosis were included. Hazards Cox regression analysis by using a competing risk regression model to control for possible confounding factors was utilized to estimate the association of the complications of liver cirrhosis with the risk of HCC. We observed by using competing risk analysis that the adjusted hazard ratio (HR) for developing HCC during the follow-up period after the initial hospitalization was higher among the patients with baseline complicated cirrhosis than in those with uncomplicated cirrhosis (HR, 1.23; 95% confidence interval, CI, 1.10-1.37, p<0.001). Additionally, older patients (HR, 1.01; 95% CI, 1.01-1.02, p<0.001), males (HR, 0.84; 95% CI, 0.74-0.96, p = 0.009), and patients with alcohol-related cirrhosis (HR, 1.93; 95% CI, 1.65-2.26, p<0.001) had a statistically significant difference in the incidence of HCC. In conclusion, complicated liver cirrhosis is associated with a higher risk of HCC in Taiwan compared with cirrhosis without complications.

Undernutrition as independent predictor of early mortality in elderly cancer patients.

PubMed

Martucci, Renata B; Barbosa, Mariana V; D'Almeida, Cristiane A; Rodrigues, Viviane D; Bergmann, Anke; de Pinho, Nivaldo B; Thuler, Luiz Claudio S

2017-02-01

The aim of this study was to evaluate the 1-y survival of elderly patients with cancer and the association between undernutrition and mortality. This was a cohort study with elderly patients ages ≥65 y admitted between September and October 2014. A nutritionist performed a Mini Nutritional Assessment-Short Form (MNA-SF) assessment during 48 h of hospital admission and collected data about potential confounding variables (comorbidities, stage of cancer, treatment in the previous 3 mo, and reason for hospitalization). Vital status was determined from the medical records or public records office. Overall survival was estimated using the Kaplan-Meier method. Cox regression was performed to estimate unadjusted hazard ratios. Variables with P < 0.20 by univariate analysis were selected for multivariate analysis. P < 0.05 was considered statistically significant. Of the 136 patients (mean age, 73.1 y; 52.2% men), 29.4%, 41.2%, and 29.4% were classified as normal, at risk for undernutrition, and undernutrition, respectively, according to the MNA-SF. The mortality rate was 31.6% after 12 mo. One-year mortality was higher among the undernourished patients, followed by patients at risk for undernutrition. After adjustment for confounding variables, the multivariate regression Cox model showed that being undernourished according to the MNA-SF increased the risk for death at 1 y (hazard ratio, 5.59; 95% confidence interval, 1.8-17.3; P < 0.001). The results showed that the MNA-SF can be a useful tool in identifying elderly patients at higher risk for 1-y mortality. Copyright © 2016 Elsevier Inc. All rights reserved.

Improving patient survival with the colorectal cancer multi-disciplinary team.

PubMed

MacDermid, E; Hooton, G; MacDonald, M; McKay, G; Grose, D; Mohammed, N; Porteous, C

2009-03-01

There is little information on the impact of the colorectal multi-disciplinary team (MDT) in the United Kingdom. Our single operator presented his patients before and after the inception of an MDT meeting in June 2002. The aim of this study was to assess the effect of this on his patients' survival, and trends in the use of adjuvant chemotherapy. Data were collected on all patients (n = 310) undergoing colectomy for colorectal cancer by one surgeon. Excluding patients with Dukes A stage, the pre-MDT cohort from January 1997 to May 2002 was 176 and the post-MDT cohort from June 2002 to December 2005 was 134. Three-year survival rates were calculated using Kaplan-Meier life table analysis. Prognostic factors were analysed using Cox-proportional hazard regression, and chemotherapy data analysed using the chi-squared test. Independent prognostic indicators of chemotherapy prescription were examined using binary logistic testing. MDT status was shown to be an independent predictor of survival on hazard regression analysis (P = 0.044). A significantly greater number of patients were prescribed adjuvant chemotherapy in the post-MDT cohort (P = 0.0002). MDT status was shown to be a significant prognostic indicator of chemotherapy prescription (P < 0.0001). Three-year survival for Dukes C patients was 58% in the pre-MDT group, and 66% in the post-MDT group (P = 0.023). There was a significant increase in patients undergoing adjuvant postoperative chemotherapy after the inception of the MDT. This was associated with a significant survival benefit in patients with Dukes C disease. The data suggest that the MDT process has resulted in an increase in the prescription of adjuvant chemotherapy, with 3-year survival being greater after its inception.

Associations Between Peer Counseling and Breastfeeding Initiation and Duration: An Analysis of Minnesota Participants in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC).

PubMed

McCoy, Marcia Burton; Geppert, Joni; Dech, Linda; Richardson, Michaela

2018-01-01

Background Peer counseling (PC) has been associated with increased breastfeeding initiation and duration, but few analyses have examined the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) model for peer counseling or the continuation of breastfeeding from birth through 12 months postpartum. Objectives Identify associations between Minnesota WIC Peer Breastfeeding Support Program services and breastfeeding initiation and continuation. Methods Retrospective analysis of observational data from the Minnesota WIC program's administrative database of women who gave birth in 2012 and accepted a PC program referral prenatally (n = 2219). Multivariate logistic regression and Cox regression models examined associations between peer services and breastfeeding initiation and continuation of any breastfeeding. Results Among women who accepted referral into a PC program, odds of initiation were significantly higher among those who received peer services (Odds Ratio (OR): 1.66; 95% CI 1.19-2.32), after adjusting for confounders. Women who received peer services had a significantly lower hazard of breastfeeding discontinuation from birth through 12 months postpartum than women who did not receive services. (Hazard Ratio (HR) month one: 0.45; 95% CI 0.33-0.61; months two through twelve: 0.33; 95% CI 0.18-0.60). The effect of peer counseling did not differ significantly by race and ethnicity, taking into account mother's country of origin. Conclusion for practice Receipt of peer services was positively associated with breastfeeding initiation and continued breastfeeding from birth through 12 months postpartum. Making peer services available to more women, especially in communities with low initiation and duration, could improve maternal and child health in Minnesota.

Analysis of perceived risk among construction workers: a cross-cultural study and reflection on the Hofstede model.

PubMed

Martinez-Fiestas, Myriam; Rodríguez-Garzón, Ignacio; Delgado-Padial, Antonio; Lucas-Ruiz, Valeriano

2017-09-01

This article presents a cross-cultural study on perceived risk in the construction industry. Worker samples from three different countries were studied: Spain, Peru and Nicaragua. The main goal was to explain how construction workers perceive their occupational hazard and to analyze how this is related to their national culture. The model used to measure perceived risk was the psychometric paradigm. The results show three very similar profiles, indicating that risk perception is independent of nationality. A cultural analysis was conducted using the Hofstede model. The results of this analysis and the relation to perceived risk showed that risk perception in construction is independent of national culture. Finally, a multiple lineal regression analysis was conducted to determine what qualitative attributes could predict the global quantitative size of risk perception. All of the findings have important implications regarding the management of safety in the workplace.

A comparison of the hazard perception ability of accident-involved and accident-free motorcycle riders.

PubMed

Cheng, Andy S K; Ng, Terry C K; Lee, Hoe C

2011-07-01

Hazard perception is the ability to read the road and is closely related to involvement in traffic accidents. It consists of both cognitive and behavioral components. Within the cognitive component, visual attention is an important function of driving whereas driving behavior, which represents the behavioral component, can affect the hazard perception of the driver. Motorcycle riders are the most vulnerable types of road user. The primary purpose of this study was to deepen our understanding of the correlation of different subtypes of visual attention and driving violation behaviors and their effect on hazard perception between accident-free and accident-involved motorcycle riders. Sixty-three accident-free and 46 accident-involved motorcycle riders undertook four neuropsychological tests of attention (Digit Vigilance Test, Color Trails Test-1, Color Trails Test-2, and Symbol Digit Modalities Test), filled out the Chinese Motorcycle Rider Driving Violation (CMRDV) Questionnaire, and viewed a road-user-based hazard situation with an eye-tracking system to record the response latencies to potentially dangerous traffic situations. The results showed that both the divided and selective attention of accident-involved motorcycle riders were significantly inferior to those of accident-free motorcycle riders, and that accident-involved riders exhibited significantly higher driving violation behaviors and took longer to identify hazardous situations compared to their accident-free counterparts. However, the results of the regression analysis showed that aggressive driving violation CMRDV score significantly predicted hazard perception and accident involvement of motorcycle riders. Given that all participants were mature and experienced motorcycle riders, the most plausible explanation for the differences between them is their driving style (influenced by an undesirable driving attitude), rather than skill deficits per se. The present study points to the importance of conceptualizing the influence of different driving behaviors so as to enrich our understanding of the role of human factors in road accidents and consequently develop effective countermeasures to prevent traffic accidents involving motorcycles. Copyright © 2011 Elsevier Ltd. All rights reserved.

Failure of anticoagulant thromboprophylaxis: risk factors in medical-surgical critically ill patients*.

PubMed

Lim, Wendy; Meade, Maureen; Lauzier, Francois; Zarychanski, Ryan; Mehta, Sangeeta; Lamontagne, Francois; Dodek, Peter; McIntyre, Lauralyn; Hall, Richard; Heels-Ansdell, Diane; Fowler, Robert; Pai, Menaka; Guyatt, Gordon; Crowther, Mark A; Warkentin, Theodore E; Devereaux, P J; Walter, Stephen D; Muscedere, John; Herridge, Margaret; Turgeon, Alexis F; Geerts, William; Finfer, Simon; Jacka, Michael; Berwanger, Otavio; Ostermann, Marlies; Qushmaq, Ismael; Friedrich, Jan O; Cook, Deborah J

2015-02-01

To identify risk factors for failure of anticoagulant thromboprophylaxis in critically ill patients in the ICU. Multivariable regression analysis of thrombosis predictors from a randomized thromboprophylaxis trial. Sixty-seven medical-surgical ICUs in six countries. Three thousand seven hundred forty-six medical-surgical critically ill patients. All patients received anticoagulant thromboprophylaxis with low-molecular-weight heparin or unfractionated heparin at standard doses. Independent predictors for venous thromboembolism, proximal leg deep vein thrombosis, and pulmonary embolism developing during critical illness were assessed. A total of 289 patients (7.7%) developed venous thromboembolism. Predictors of thromboprophylaxis failure as measured by development of venous thromboembolism included a personal or family history of venous thromboembolism (hazard ratio, 1.64; 95% CI, 1.03-2.59; p = 0.04) and body mass index (hazard ratio, 1.18 per 10-point increase; 95% CI, 1.04-1.35; p = 0.01). Increasing body mass index was also a predictor for developing proximal leg deep vein thrombosis (hazard ratio, 1.25; 95% CI, 1.06-1.46; p = 0.007), which occurred in 182 patients (4.9%). Pulmonary embolism occurred in 47 patients (1.3%) and was associated with body mass index (hazard ratio, 1.37; 95% CI, 1.02-1.83; p = 0.035) and vasopressor use (hazard ratio, 1.84; 95% CI, 1.01-3.35; p = 0.046). Low-molecular-weight heparin (in comparison to unfractionated heparin) thromboprophylaxis lowered pulmonary embolism risk (hazard ratio, 0.51; 95% CI, 0.27-0.95; p = 0.034) while statin use in the preceding week lowered the risk of proximal leg deep vein thrombosis (hazard ratio, 0.46; 95% CI, 0.27-0.77; p = 0.004). Failure of standard thromboprophylaxis using low-molecular-weight heparin or unfractionated heparin is more likely in ICU patients with elevated body mass index, those with a personal or family history of venous thromboembolism, and those receiving vasopressors. Alternate management or incremental risk reduction strategies may be needed in such patients.

Do spouses coordinate their work exits? A combined survey and register analysis from Norway.

PubMed

Syse, Astri; Solem, Per Erik; Ugreninov, Elisabeth; Mykletun, Reidar; Furunes, Trude

2014-09-01

Research on spouses' joint work exits is scarce, although household factors such as spouses' work status, marital quality, and caregiving burdens are likely to affect seniors' work engagement. We therefore examine whether the work exit probability of one spouse affects that of the other. Discrete-time hazard regression analyses of survey data linked to later registry information including all gainfully employed married respondents aged 50-74 with a working spouse (N = 1,764) were used to assess subsequent work exits. A spouse's work exit is a strong predictor of a respondent's work exit (hazard ratio 3.1, 95% confidence interval [2.5, 4.0]). Educational attainment, poor marital quality, and spouses' health and care needs do not predict work exits. Surprisingly, no gender differences are observed. Research on larger survey samples to distinguish different work exit routes and reasons for spouses' joint work exits appears warranted. To account for cultural and welfare state characteristics, cross-national studies ought to be undertaken. © The Author(s) 2013.

Variable selection in semiparametric cure models based on penalized likelihood, with application to breast cancer clinical trials.

PubMed

Liu, Xiang; Peng, Yingwei; Tu, Dongsheng; Liang, Hua

2012-10-30

Survival data with a sizable cure fraction are commonly encountered in cancer research. The semiparametric proportional hazards cure model has been recently used to analyze such data. As seen in the analysis of data from a breast cancer study, a variable selection approach is needed to identify important factors in predicting the cure status and risk of breast cancer recurrence. However, no specific variable selection method for the cure model is available. In this paper, we present a variable selection approach with penalized likelihood for the cure model. The estimation can be implemented easily by combining the computational methods for penalized logistic regression and the penalized Cox proportional hazards models with the expectation-maximization algorithm. We illustrate the proposed approach on data from a breast cancer study. We conducted Monte Carlo simulations to evaluate the performance of the proposed method. We used and compared different penalty functions in the simulation studies. Copyright © 2012 John Wiley & Sons, Ltd.

Coastal dynamics studies for evaluation of hazard and vulnerability for coastal erosion. case study the town La Bocana, Buenaventura, colombian pacific

NASA Astrophysics Data System (ADS)

Coca-Domínguez, Oswaldo; Ricaurte-Villota, Constanza

2015-04-01

The analysis of the hazard and vulnerability in coastal areas caused for erosion is based on studies of coastal dynamics since that allows having a better information detail that is useful for decision-making in aspects like prevention, mitigation, disaster reduction and integrated risk management. The Town of La Bocana, located in Buenaventura (Colombian Pacific) was selected to carry out the threat assessment for coastal erosion based on three components: i) magnitude, ii) occurrence and iii) susceptibility. Vulnerability meanwhile, is also composed of three main components for its evaluation: i) exposure ii) fragility and iii) resilience, which in turn are evaluated in 6 dimensions of vulnerability: physical, social, economic, ecological, institutional and cultural. The hazard analysis performed used a semi-quantitative approach, and an index of variables such as type of geomorphological unit, type of beach, exposure of the surfing coast, occurrence, among others. Quantitative data of coastal retreat was measured through the use of DSAS (Digital Shoreline Analysis System) an application of ArcGIS, as well as the development of digital elevation models from the beach and 6 beach profiles strategically located on the coast obtained with GNSS technology. Sediment samples collected from these beaches, medium height and wave direction were used as complementary data. The information was integrated across the coast line into segments of 250 x 250 meters. 4 sectors are part of the coastal area of La Bocana: Pianguita, Vistahermosa, Donwtown and Shangay. 6 vulnerability dimensions units were taken from these population, as well as its density for exposure, wich was analyzed through a multi-array method that include variables such as, land use, population, type of structure, education, basic services, among others, to measure frailty, and their respective indicator of resilience. The hazard analysis results indicate that Vistahermosa is in very high threat, while Donwtown and Pianguita are in a medium hazard. Particularly these two sectors have the mayor population density and the biggest hotel development and services infraestructure; meanwhile Shangay was scored with low hazard because the wave action has no direct impact on it. Vulnerability analysis suggest that the sector of Shangay has a very high vulnerability status because it is a sector that does not have any basic services and have low levels of schooling, meanwhile Downtown, Vistahermosa and Pianguita are in the average of vulnerability. Additionally, it was determined that in recent years the sector of Vista hermosa the erosion rates are up to -xx m yr-1, while in other sectors the regression of the coastline can be associated with local tidal peaks that occur during April and October, while other months of the year are typically for recovery and stability processes.

Comparison and validation of statistical methods for predicting power outage durations in the event of hurricanes.

PubMed

Nateghi, Roshanak; Guikema, Seth D; Quiring, Steven M

2011-12-01

This article compares statistical methods for modeling power outage durations during hurricanes and examines the predictive accuracy of these methods. Being able to make accurate predictions of power outage durations is valuable because the information can be used by utility companies to plan their restoration efforts more efficiently. This information can also help inform customers and public agencies of the expected outage times, enabling better collective response planning, and coordination of restoration efforts for other critical infrastructures that depend on electricity. In the long run, outage duration estimates for future storm scenarios may help utilities and public agencies better allocate risk management resources to balance the disruption from hurricanes with the cost of hardening power systems. We compare the out-of-sample predictive accuracy of five distinct statistical models for estimating power outage duration times caused by Hurricane Ivan in 2004. The methods compared include both regression models (accelerated failure time (AFT) and Cox proportional hazard models (Cox PH)) and data mining techniques (regression trees, Bayesian additive regression trees (BART), and multivariate additive regression splines). We then validate our models against two other hurricanes. Our results indicate that BART yields the best prediction accuracy and that it is possible to predict outage durations with reasonable accuracy. © 2011 Society for Risk Analysis.

Risk perception and access to environmental information in four areas in Italy affected by natural or anthropogenic pollution.

PubMed

Coi, A; Minichilli, F; Bustaffa, E; Carone, S; Santoro, M; Bianchi, F; Cori, L

2016-10-01

A human biomonitoring (HBM) survey in four areas affected by natural or anthropogenic arsenic pollution was conducted in Italy within the framework of the SEpiAs project. A questionnaire, including the exploration of risk perception (RP) regarding environmental hazards and access to and trust in information, was administered to 282 subjects stratified by area, gender and age. The survey was designed to investigate how populations living in polluted areas could adopt prevention-oriented habits, fostered by the awareness of existing risks and, in addition, how increased knowledge of RP and information flows could support researchers in identifying recommendations, and presenting and disseminating HBM results. This study characterizes the four areas in terms of RP and access to and trust in environmental information, and provides insights into the influence of RP and environmental information on food consumption. For the data analysis, a combined random forest (RF) and logistic regression approach was carried out. RF was applied to the variables derived from the questionnaire in order to identify the most important in terms of the aims defined. Associations were then tested using Fisher's exact test and assessed with logistic regression in order to adjust for confounders. Results showed that the perception of and personal exposure to atmospheric and water pollution, hazardous industries and waste, hazardous material transportation and waste was higher in geographical areas characterized by anthropogenic pollution. Citizens living in industrial areas appeared to be aware of environmental risks and had more confidence in environmental non-governmental organizations (NGOs) than in public authorities. In addition, they reported an insufficient circulation of information. Concerning the influence of RP and environmental information on food consumption, a high perception of personal exposure to atmospheric pollution and hazardous industries was associated with a lower consumption of local fish. In conclusion, different RPs and information flow patterns were observed in areas with arsenic of natural origin or in industrial contexts. These findings may be useful for targeted risk communication plans in support of risk-management strategies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Building vulnerability to hydro-geomorphic hazards: Estimating damage probability from qualitative vulnerability assessment using logistic regression

NASA Astrophysics Data System (ADS)

Ettinger, Susanne; Mounaud, Loïc; Magill, Christina; Yao-Lafourcade, Anne-Françoise; Thouret, Jean-Claude; Manville, Vern; Negulescu, Caterina; Zuccaro, Giulio; De Gregorio, Daniela; Nardone, Stefano; Uchuchoque, Juan Alexis Luque; Arguedas, Anita; Macedo, Luisa; Manrique Llerena, Nélida

2016-10-01

The focus of this study is an analysis of building vulnerability through investigating impacts from the 8 February 2013 flash flood event along the Avenida Venezuela channel in the city of Arequipa, Peru. On this day, 124.5 mm of rain fell within 3 h (monthly mean: 29.3 mm) triggering a flash flood that inundated at least 0.4 km2 of urban settlements along the channel, affecting more than 280 buildings, 23 of a total of 53 bridges (pedestrian, vehicle and railway), and leading to the partial collapse of sections of the main road, paralyzing central parts of the city for more than one week. This study assesses the aspects of building design and site specific environmental characteristics that render a building vulnerable by considering the example of a flash flood event in February 2013. A statistical methodology is developed that enables estimation of damage probability for buildings. The applied method uses observed inundation height as a hazard proxy in areas where more detailed hydrodynamic modeling data is not available. Building design and site-specific environmental conditions determine the physical vulnerability. The mathematical approach considers both physical vulnerability and hazard related parameters and helps to reduce uncertainty in the determination of descriptive parameters, parameter interdependency and respective contributions to damage. This study aims to (1) enable the estimation of damage probability for a certain hazard intensity, and (2) obtain data to visualize variations in damage susceptibility for buildings in flood prone areas. Data collection is based on a post-flood event field survey and the analysis of high (sub-metric) spatial resolution images (Pléiades 2012, 2013). An inventory of 30 city blocks was collated in a GIS database in order to estimate the physical vulnerability of buildings. As many as 1103 buildings were surveyed along the affected drainage and 898 buildings were included in the statistical analysis. Univariate and bivariate analyses were applied to better characterize each vulnerability parameter. Multiple corresponding analyses revealed strong relationships between the "Distance to channel or bridges", "Structural building type", "Building footprint" and the observed damage. Logistic regression enabled quantification of the contribution of each explanatory parameter to potential damage, and determination of the significant parameters that express the damage susceptibility of a building. The model was applied 200 times on different calibration and validation data sets in order to examine performance. Results show that 90% of these tests have a success rate of more than 67%. Probabilities (at building scale) of experiencing different damage levels during a future event similar to the 8 February 2013 flash flood are the major outcomes of this study.

Effect of Home Blood Pressure on Inducing Remission/Regression of Microalbuminuria in Patients With Type 2 Diabetes Mellitus.

PubMed

Nishimura, Motonobu; Kato, Yasuhisa; Tanaka, Tsuyoshi; Taki, Hideki; Tone, Atsuhito; Yamada, Kazunori; Suzuki, Seiji; Saito, Miho; Ando, Yutaka; Hoshiyama, Yoshiharu

2017-08-01

The Home Blood Pressure for Diabetic Nephropathy study is a prospective observational study conducted to determine the effect of home blood pressure (HBP) on remission/regression of microalbuminuria in patients with type 2 diabetes mellitus (DM). Patients with type 2 DM having microalbuminuria were followed-up for 3 years. Remission of microalbuminuria was defined as shift from microalbuminuria to normoalbuminuria. Regression of microalbuminuria was defined as a 50% reduction in urinary albumin-creatinine ratio from baseline. All measurements of morning and evening HBP were averaged every year and defined as all HBP. In total, 235 patients were followed up. The 3-year cumulative incidences of remission and regression were 32.3% and 44.7%, respectively. Following analysis of all cases, the degree of decline in all home systolic blood pressure (AHSBP), rather than mean AHSBP, influenced the incidence of remission/regression. There was a strong relationship between the decline in AHSBP during the follow-up period and AHSBP at baseline. Therefore, separate analyses of the patients with AHSBP below 140 mm Hg at baseline were performed, which revealed that mean AHSBP during the follow-up period independently affected the incidence of remission/regression. The hazard ratio for inducing remission/regression was significantly lower in patients with AHSBP during the follow-up period above 130 mm Hg than in those with AHSBP below 120 mm Hg. Optimal AHSBP for the induction of remission/regression of microalbuminuria might be below 130 mm Hg. It is required to confirm whether keeping AHSBP below 130 mm Hg leads to subsequent renoprotection or not. Trial Number UMIN000000804. © American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Overexpression of epithelial cell adhesion molecule protein is associated with favorable prognosis in an unselected cohort of ovarian cancer patients.

PubMed

Battista, Marco Johannes; Cotarelo, Cristina; Jakobi, Sina; Steetskamp, Joscha; Makris, Georgios; Sicking, Isabel; Weyer, Veronika; Schmidt, Marcus

2014-07-01

The aim of this study was to evaluate the prognostic influence of epithelial cell adhesion molecule (EpCAM) in an unselected cohort of ovarian cancer (OC) patients. Expression of EpCAM was determined by immunohistochemistry in an unselected cohort of 117 patients with OC. Univariable and multivariable Cox regression analyses adjusted for age, tumor stage, histological grading, histological subtype, postoperative tumor burden and completeness of chemotherapy were performed in order to determine the prognostic influence of EpCAM. The Kaplan-Meier method is used to estimate survival rates. Univariable Cox regression analysis showed that overexpression of EpCAM is associated with favorable prognosis in terms of progression-free survival (PFS) (p = 0.011) and disease-specific survival (DSS) (p = 0.003). In multivariable Cox regression analysis, overexpression of EpCAM retains its significance independent of established prognostic factors for longer PFS [hazard ratios (HR) 0.408, 95 % confidence interval (CI) 0.197-0.846, p = 0.003] but not for PFS (HR 0.666, 95 % CI 0.366-1.212, p = 0.183). Kaplan-Meier plots demonstrate an influence on 5-year PFS rates (0 vs. 27.6 %, p = 0.048) and DSS rates (11.8 vs. 54.0 %, p = 0.018). These findings support the hypothesis that the expression of EpCAM is associated with favorable prognosis in OC.

Proportional exponentiated link transformed hazards (ELTH) models for discrete time survival data with application

PubMed Central

Joeng, Hee-Koung; Chen, Ming-Hui; Kang, Sangwook

2015-01-01

Discrete survival data are routinely encountered in many fields of study including behavior science, economics, epidemiology, medicine, and social science. In this paper, we develop a class of proportional exponentiated link transformed hazards (ELTH) models. We carry out a detailed examination of the role of links in fitting discrete survival data and estimating regression coefficients. Several interesting results are established regarding the choice of links and baseline hazards. We also characterize the conditions for improper survival functions and the conditions for existence of the maximum likelihood estimates under the proposed ELTH models. An extensive simulation study is conducted to examine the empirical performance of the parameter estimates under the Cox proportional hazards model by treating discrete survival times as continuous survival times, and the model comparison criteria, AIC and BIC, in determining links and baseline hazards. A SEER breast cancer dataset is analyzed in details to further demonstrate the proposed methodology. PMID:25772374

The costs of hazardous alcohol consumption in Germany.

PubMed

Effertz, Tobias; Verheyen, Frank; Linder, Roland

2017-07-01

Hazardous alcohol consumption in Germany is a main threat to health. By using insurance claim data from the German Statutory Health Insurance and a classification strategy based on ICD10 diagnoses-codes we analyzed a sample of 146,000 subjects with more than 19,000 hazardous alcohol consumers. Employing different regression models with a control function approach, we calculate life years lost due to alcohol consumption, annual direct and indirect health costs, and the burden of pain and suffering measured by the Charlson-Index and assessed pain diagnoses. Additionally, we simulate the net accumulated premium payments over expenses in the German Statutory Health Insurance and the Statutory Pension Fund for hazardous alcohol consumers from a lifecycle perspective. In total, €39.3 billion each year result from hazardous alcohol consumption with an average loss of 7 years in life expectancy. Hazardous alcohol consumers clearly do not "pay their way" in the two main German social security systems and also display a higher intangible burden according to our definitions of pain and suffering.

Prostate cancer: role of pretreatment multiparametric 3-T MRI in predicting biochemical recurrence after radical prostatectomy.

PubMed

Park, Jung Jae; Kim, Chan Kyo; Park, Sung Yoon; Park, Byung Kwan; Lee, Hyun Moo; Cho, Seong Whi

2014-05-01

The purpose of this study is to retrospectively investigate whether pretreatment multiparametric MRI findings can predict biochemical recurrence in patients who underwent radical prostatectomy (RP) for localized prostate cancer. In this study, 282 patients with biopsy-proven prostate cancer who received RP underwent pretreatment MRI using a phased-array coil at 3 T, including T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and dynamic contrast-enhanced MRI (DCE-MRI). MRI variables included apparent tumor presence on combined imaging sequences, extracapsular extension, and tumor size on DWI or DCE-MRI. Clinical variables included baseline prostate-specific antigen (PSA) level, clinical stage, and Gleason score at biopsy. The relationship between clinical and imaging variables and biochemical recurrence was evaluated using Cox regression analysis. After a median follow-up of 26 months, biochemical recurrence developed in 61 patients (22%). Univariate analysis revealed that all the imaging and clinical variables were significantly associated with biochemical recurrence (p < 0.01). On multivariate analysis, however, baseline PSA level (p = 0.002), Gleason score at biopsy (p = 0.024), and apparent tumor presence on combined T2WI, DWI, and DCE-MRI (p = 0.047) were the only significant independent predictors of biochemical recurrence. Of the independent predictors, apparent tumor presence on combined T2WI, DWI, and DCE-MRI showed the highest hazard ratio (2.38) compared with baseline PSA level (hazard ratio, 1.05) and Gleason score at biopsy (hazard ratio, 1.34). The apparent tumor presence on combined T2WI, DWI, and DCE-MRI of pretreatment MRI is an independent predictor of biochemical recurrence after RP. This finding may be used to construct a predictive model for biochemical recurrence after surgery.

Propensity Score–Matched Analysis of Comprehensive Local Therapy for Oligometastatic Non-Small Cell Lung Cancer That Did Not Progress After Front-Line Chemotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheu, Tommy; Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas; Heymach, John V.

2014-11-15

Purpose: To retrospectively analyze factors influencing survival in patients with non-small cell lung cancer presenting with ≤3 synchronous metastatic lesions. Methods and Materials: We identified 90 patients presenting between 1998 and 2012 with non-small cell lung cancer and ≤3 metastatic lesions who had received at least 2 cycles of chemotherapy followed by surgery or radiation therapy before disease progression. The median number of chemotherapy cycles before comprehensive local therapy (CLT) (including concurrent chemoradiation as first-line therapy) was 6. Factors potentially affecting overall (OS) or progression-free survival (PFS) were evaluated with Cox proportional hazards regression. Propensity score matching was used to assessmore » the efficacy of CLT. Results: Median follow-up time was 46.6 months. Benefits in OS (27.1 vs 13.1 months) and PFS (11.3 months vs 8.0 months) were found with CLT, and the differences were statistically significant when propensity score matching was used (P ≤ .01). On adjusted analysis, CLT had a statistically significant benefit in terms of OS (hazard ratio, 0.37; 95% confidence interval, 0.20-0.70; P ≤ .01) but not PFS (P=.10). In an adjusted subgroup analysis of patients receiving CLT, favorable performance status (hazard ratio, 0.43; 95% confidence interval, 0.22-0.84; P=.01) was found to predict improved OS. Conclusions: Comprehensive local therapy was associated with improved OS in an adjusted analysis and seemed to favorably influence OS and PFS when factors such as N status, number of metastatic lesions, and disease sites were controlled for with propensity score–matched analysis. Patients with favorable performance status had improved outcomes with CLT. Ultimately, prospective, randomized trials are needed to provide definitive evidence as to the optimal treatment approach for this patient population.« less

National Cancer Database Analysis of Proton Versus Photon Radiation Therapy in Non-Small Cell Lung Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Higgins, Kristin A., E-mail: kristin.higgins@emory.edu; Winship Cancer Institute, Emory University, Atlanta, Georgia; O'Connell, Kelli

Purpose: To analyze outcomes and predictors associated with proton radiation therapy for non-small cell lung cancer (NSCLC) in the National Cancer Database. Methods and Materials: The National Cancer Database was queried to capture patients with stage I-IV NSCLC treated with thoracic radiation from 2004 to 2012. A logistic regression model was used to determine the predictors for utilization of proton radiation therapy. The univariate and multivariable association with overall survival were assessed by Cox proportional hazards models along with log–rank tests. A propensity score matching method was implemented to balance baseline covariates and eliminate selection bias. Results: A total of 243,822more » patients (photon radiation therapy: 243,474; proton radiation therapy: 348) were included in the analysis. Patients in a ZIP code with a median income of <$46,000 per year were less likely to receive proton treatment, with the income cohort of $30,000 to $35,999 least likely to receive proton therapy (odds ratio 0.63 [95% confidence interval (CI) 0.44-0.90]; P=.011). On multivariate analysis of all patients, non-proton therapy was associated with significantly worse survival compared with proton therapy (hazard ratio 1.21 [95% CI 1.06-1.39]; P<.01). On propensity matched analysis, proton radiation therapy (n=309) was associated with better 5-year overall survival compared with non-proton radiation therapy (n=1549), 22% versus 16% (P=.025). For stage II and III patients, non-proton radiation therapy was associated with worse survival compared with proton radiation therapy (hazard ratio 1.35 [95% CI 1.10-1.64], P<.01). Conclusions: Thoracic radiation with protons is associated with better survival in this retrospective analysis; further validation in the randomized setting is needed to account for any imbalances in patient characteristics, including positron emission tomography–computed tomography staging.« less

Propensity score-matched analysis of comprehensive local therapy for oligometastatic non-small cell lung cancer that did not progress after front-line chemotherapy.

PubMed

Sheu, Tommy; Heymach, John V; Swisher, Stephen G; Rao, Ganesh; Weinberg, Jeffrey S; Mehran, Reza; McAleer, Mary Frances; Liao, Zhongxing; Aloia, Thomas A; Gomez, Daniel R

2014-11-15

To retrospectively analyze factors influencing survival in patients with non-small cell lung cancer presenting with ≤3 synchronous metastatic lesions. We identified 90 patients presenting between 1998 and 2012 with non-small cell lung cancer and ≤3 metastatic lesions who had received at least 2 cycles of chemotherapy followed by surgery or radiation therapy before disease progression. The median number of chemotherapy cycles before comprehensive local therapy (CLT) (including concurrent chemoradiation as first-line therapy) was 6. Factors potentially affecting overall (OS) or progression-free survival (PFS) were evaluated with Cox proportional hazards regression. Propensity score matching was used to assess the efficacy of CLT. Median follow-up time was 46.6 months. Benefits in OS (27.1 vs 13.1 months) and PFS (11.3 months vs 8.0 months) were found with CLT, and the differences were statistically significant when propensity score matching was used (P ≤ .01). On adjusted analysis, CLT had a statistically significant benefit in terms of OS (hazard ratio, 0.37; 95% confidence interval, 0.20-0.70; P ≤ .01) but not PFS (P=.10). In an adjusted subgroup analysis of patients receiving CLT, favorable performance status (hazard ratio, 0.43; 95% confidence interval, 0.22-0.84; P=.01) was found to predict improved OS. Comprehensive local therapy was associated with improved OS in an adjusted analysis and seemed to favorably influence OS and PFS when factors such as N status, number of metastatic lesions, and disease sites were controlled for with propensity score-matched analysis. Patients with favorable performance status had improved outcomes with CLT. Ultimately, prospective, randomized trials are needed to provide definitive evidence as to the optimal treatment approach for this patient population. Copyright © 2014 Elsevier Inc. All rights reserved.

A novel hazard assessment method for biomass gasification stations based on extended set pair analysis

PubMed Central

Yan, Fang; Xu, Kaili; Li, Deshun; Cui, Zhikai

2017-01-01

Biomass gasification stations are facing many hazard factors, therefore, it is necessary to make hazard assessment for them. In this study, a novel hazard assessment method called extended set pair analysis (ESPA) is proposed based on set pair analysis (SPA). However, the calculation of the connection degree (CD) requires the classification of hazard grades and their corresponding thresholds using SPA for the hazard assessment. In regard to the hazard assessment using ESPA, a novel calculation algorithm of the CD is worked out when hazard grades and their corresponding thresholds are unknown. Then the CD can be converted into Euclidean distance (ED) by a simple and concise calculation, and the hazard of each sample will be ranked based on the value of ED. In this paper, six biomass gasification stations are introduced to make hazard assessment using ESPA and general set pair analysis (GSPA), respectively. By the comparison of hazard assessment results obtained from ESPA and GSPA, the availability and validity of ESPA can be proved in the hazard assessment for biomass gasification stations. Meanwhile, the reasonability of ESPA is also justified by the sensitivity analysis of hazard assessment results obtained by ESPA and GSPA. PMID:28938011

14 CFR 437.55 - Hazard analysis.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Hazard analysis. 437.55 Section 437.55... TRANSPORTATION LICENSING EXPERIMENTAL PERMITS Safety Requirements § 437.55 Hazard analysis. (a) A permittee must... safety of property resulting from each permitted flight. This hazard analysis must— (1) Identify and...

14 CFR 437.55 - Hazard analysis.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Hazard analysis. 437.55 Section 437.55... TRANSPORTATION LICENSING EXPERIMENTAL PERMITS Safety Requirements § 437.55 Hazard analysis. (a) A permittee must... safety of property resulting from each permitted flight. This hazard analysis must— (1) Identify and...

Hydrotreater/Distillation Column Hazard Analysis Report Rev. 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lowry, Peter P.; Wagner, Katie A.

This project Hazard and Risk Analysis Report contains the results of several hazard analyses and risk assessments. An initial assessment was conducted in 2012, which included a multi-step approach ranging from design reviews to a formal What-If hazard analysis. A second What-If hazard analysis was completed during February 2013 to evaluate the operation of the hydrotreater/distillation column processes to be installed in a process enclosure within the Process Development Laboratory West (PDL-West) facility located on the PNNL campus. The qualitative analysis included participation of project and operations personnel and applicable subject matter experts. The analysis identified potential hazardous scenarios, eachmore » based on an initiating event coupled with a postulated upset condition. The unmitigated consequences of each hazardous scenario were generally characterized as a process upset; the exposure of personnel to steam, vapors or hazardous material; a spray or spill of hazardous material; the creation of a flammable atmosphere; or an energetic release from a pressure boundary.« less

Blood Glucose Reduction by Diabetic Drugs with Minimal Hypoglycemia Risk for Cardiovascular Outcomes: Evidence from Meta-regression Analysis of Randomized Controlled Trials.

PubMed

Huang, Chi-Jung; Wang, Wei-Ting; Sung, Shih-Hsien; Chen, Chen-Huan; Lip, Gregory Yh; Cheng, Hao-Min; Chiang, Chern-En

2018-05-02

To investigate the effects of blood glucose control with antihyperglycemic agents with minimal hypoglycemia risk on cardiovascular outcomes in patients with type 2 diabetes (T2D). Randomized controlled trials (RCTs) comparing the relative efficacy and safety of antidiabetic drugs with less hypoglycemia risk were comprehensively searched in MEDLINE, Embase, and the Cochrane Library up to January 27, 2018. Mixed-effects meta-regression analysis was conducted to explore the relationship between haemoglobin A1c (HbA1c) reduction and the risk of major adverse cardiovascular events (MACE), myocardial infarction, stroke, cardiovascular death, all-cause death, and hospitalization for heart failure. Ten RCTs comprising 92400 participants with T2D were included and provided information on 9773 MACE during a median follow-up of 2.6 years. The mean HbA1c concentration was 0.42% lower (median, 0.27-0.86%) for participants given antihyperglycemic agents than those given placebo. The meta-regression analysis demonstrated that HbA1c reduction was significantly associated with a decreased risk of MACE (β value, -0.39 to -0.55; P<0.02) even after adjusting for each of the following possible confounding factors including age, sex, baseline HbA1c, duration of follow-up, difference in achieved systolic blood pressure, difference in achieved body weight, or risk difference in hypoglycemia. Lowering HbA1c by 1% conferred a significant risk reduction of 30% (95% CI, 17-40%) for MACE. By contrast, the meta-regression analysis for trials using conventional agents failed to demonstrate a significant relationship between achieved HbA1c difference and MACE risk (P>0.74). Compared with placebo, newer T2D agents with less hypoglycemic hazard significantly reduced the risk of MACE. The MACE reduction seems to be associated with HbA1c reduction in a linear relationship. This article is protected by copyright. All rights reserved.

Automated Hazard Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riddle, F. J.

2003-06-26

The Automated Hazard Analysis (AHA) application is a software tool used to conduct job hazard screening and analysis of tasks to be performed in Savannah River Site facilities. The AHA application provides a systematic approach to the assessment of safety and environmental hazards associated with specific tasks, and the identification of controls regulations, and other requirements needed to perform those tasks safely. AHA is to be integrated into existing Savannah River site work control and job hazard analysis processes. Utilization of AHA will improve the consistency and completeness of hazard screening and analysis, and increase the effectiveness of the workmore » planning process.« less

Hydrothermal Liquefaction Treatment Hazard Analysis Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lowry, Peter P.; Wagner, Katie A.

Hazard analyses were performed to evaluate the modular hydrothermal liquefaction treatment system. The hazard assessment process was performed in 2 stages. An initial assessment utilizing Hazard Identification and Preliminary Hazards Analysis (PHA) techniques identified areas with significant or unique hazards (process safety-related hazards) that fall outside of the normal operating envelope of PNNL and warranted additional analysis. The subsequent assessment was based on a qualitative What-If analysis. The analysis was augmented, as necessary, by additional quantitative analysis for scenarios involving a release of hazardous material or energy with the potential for affecting the public. The following selected hazardous scenarios receivedmore » increased attention: •Scenarios involving a release of hazardous material or energy, controls were identified in the What-If analysis table that prevent the occurrence or mitigate the effects of the release. •Scenarios with significant consequences that could impact personnel outside the immediate operations area, quantitative analyses were performed to determine the potential magnitude of the scenario. The set of “critical controls” were identified for these scenarios (see Section 4) which prevent the occurrence or mitigate the effects of the release of events with significant consequences.« less

[Present state of occupational hazards in automobile maintenance industry in Beijing, China].

PubMed

Li, Jue; Wang, Huining; Wang, Zhongxu; Wang, Hong; Niu, Dongsheng; Xu, Xiaohong; Sun, Wei

2014-06-01

To explore the present state of occupational hazards and health status of workers in the automobile maintenance industry. The monitoring results of occupational hazards in 25 automobile maintenance companies, occupational health examination results of 751 male workers in 63 automobile maintenance companies, and physical examination results of 205 male students in one Research Institute were statistically analyzed in 2012. The concentrations of benzene, toluene, xylene, ethyl acetate, and butyl acetate in the workplace were 0.3∼21.7, 0.4∼40.3, 0.4∼84.8, 1.9∼34.3, and 0.7∼516.7 mg/m(3), respectively; benzene concentration exceeded the upper limit in two workplaces, and butyl acetate concentration exceeded the upper limit in one workplace. The intensity of noise was 70.3∼ 91.3 dB (A) and exceeded the upper limit in one workplace. The prevalence of blood system involvement in spray painters was 15.6%, significant higher than that of the control group (P < 0.05). High-frequency hearing loss was detected in 53.9%of all metalers. Logistic regression analysis indicated that blood system involvement was not correlated with age and working years in spray painters; high-frequency hearing loss in metalers was positively correlated with age, but not correlated with working years. The status of occupational hazards in the automobile maintenance industry should not be neglected, and the management of noxious positions and personal protection should be strengthened in enterprises.

Alcohol use disorders and hazardous drinking among undergraduates at English universities.

PubMed

Heather, Nick; Partington, Sarah; Partington, Elizabeth; Longstaff, Fran; Allsop, Susan; Jankowski, Mark; Wareham, Helen; St Clair Gibson, Alan

2011-01-01

To report on alcohol use disorders and hazardous drinking from a survey of university students in England in 2008-2009. A cross-sectional survey using the Alcohol Use Disorders Identification Test (AUDIT) was carried out in a purposive sample of 770 undergraduates from seven universities across England. Sixty-one per cent of the sample (65% men; 58% women) scored positive (8+) on the AUDIT, comprising 40% hazardous drinkers, 11% harmful drinkers and 10% with probable dependence. There were large and significant differences in mean AUDIT scores between the universities taking part in the survey. Two universities in the North of England showed a significantly higher combined mean AUDIT score than two universities in the Midlands which in turn showed a significantly higher mean AUDIT score than three universities in the South. When the effects of university attended were extracted in a binary logistic regression analysis, independent significant predictors of AUDIT positive status were younger age, 'White' ethnicity and both on-campus and off-campus term-time student accommodation. Undergraduates at some universities in England show very high levels of alcohol-related risk and harm. University authorities should estimate the level of hazardous drinking and alcohol use disorders among students at their institutions and take action to reduce risk and harm accordingly. Research is needed using nationally representative samples to estimate the prevalence of alcohol risk and harm in the UK student population and to determine the future course of drinking problems among students currently affected.

Hazard Analysis for Building 34 Vacuum Glove Box Assembly

NASA Technical Reports Server (NTRS)

Meginnis, Ian

2014-01-01

One of the characteristics of an effective safety program is the recognition and control of hazards before mishaps or failures occur. Conducting potentially hazardous tests necessitates a thorough hazard analysis in order to prevent injury to personnel, and to prevent damage to facilities and equipment. The primary purpose of this hazard analysis is to define and address the potential hazards and controls associated with the Building 34 Vacuum Glove Box Assembly, and to provide the applicable team of personnel with the documented results. It is imperative that each member of the team be familiar with the hazards and controls associated with his/her particular tasks, assignments and activities while interfacing with facility test systems, equipment and hardware. In fulfillment of the stated purposes, the goal of this hazard analysis is to identify all hazards that have the potential to harm personnel, damage the facility or its test systems or equipment, test articles, Government or personal property, or the environment. This analysis may also assess the significance and risk, when applicable, of lost test objectives when substantial monetary value is involved. The hazards, causes, controls, verifications, and risk assessment codes have been documented on the hazard analysis work sheets in Appendix A of this document. The preparation and development of this report is in accordance with JPR 1700.1, "JSC Safety and Health Handbook" and JSC 17773 Rev D "Instructions for Preparation of Hazard Analysis for JSC Ground Operations".

Earthquakes Magnitude Predication Using Artificial Neural Network in Northern Red Sea Area

NASA Astrophysics Data System (ADS)

Alarifi, A. S.; Alarifi, N. S.

2009-12-01

Earthquakes are natural hazards that do not happen very often, however they may cause huge losses in life and property. Early preparation for these hazards is a key factor to reduce their damage and consequence. Since early ages, people tried to predicate earthquakes using simple observations such as strange or a typical animal behavior. In this paper, we study data collected from existing earthquake catalogue to give better forecasting for future earthquakes. The 16000 events cover a time span of 1970 to 2009, the magnitude range from greater than 0 to less than 7.2 while the depth range from greater than 0 to less than 100km. We propose a new artificial intelligent predication system based on artificial neural network, which can be used to predicate the magnitude of future earthquakes in northern Red Sea area including the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez. We propose a feed forward new neural network model with multi-hidden layers to predicate earthquakes occurrences and magnitudes in northern Red Sea area. Although there are similar model that have been published before in different areas, to our best knowledge this is the first neural network model to predicate earthquake in northern Red Sea area. Furthermore, we present other forecasting methods such as moving average over different interval, normally distributed random predicator, and uniformly distributed random predicator. In addition, we present different statistical methods and data fitting such as linear, quadratic, and cubic regression. We present a details performance analyses of the proposed methods for different evaluation metrics. The results show that neural network model provides higher forecast accuracy than other proposed methods. The results show that neural network achieves an average absolute error of 2.6% while an average absolute error of 3.8%, 7.3% and 6.17% for moving average, linear regression and cubic regression, respectively. In this work, we show an analysis of earthquakes data in northern Red Sea area for different statistics parameters such as correlation, mean, standard deviation, and other. This analysis is to provide a deep understand of the Seismicity of the area, and existing patterns.

Conversion of Local and Surface-Wave Magnitudes to Moment Magnitude for Earthquakes in the Chinese Mainland

NASA Astrophysics Data System (ADS)

Li, X.; Gao, M.

2017-12-01

The magnitude of an earthquake is one of its basic parameters and is a measure of its scale. It plays a significant role in seismology and earthquake engineering research, particularly in the calculations of the seismic rate and b value in earthquake prediction and seismic hazard analysis. However, several current types of magnitudes used in seismology research, such as local magnitude (ML), surface wave magnitude (MS), and body-wave magnitude (MB), have a common limitation, which is the magnitude saturation phenomenon. Fortunately, the problem of magnitude saturation was solved by a formula for calculating the seismic moment magnitude (MW) based on the seismic moment, which describes the seismic source strength. Now the moment magnitude is very commonly used in seismology research. However, in China, the earthquake scale is primarily based on local and surface-wave magnitudes. In the present work, we studied the empirical relationships between moment magnitude (MW) and local magnitude (ML) as well as surface wave magnitude (MS) in the Chinese Mainland. The China Earthquake Networks Center (CENC) ML catalog, China Seismograph Network (CSN) MS catalog, ANSS Comprehensive Earthquake Catalog (ComCat), and Global Centroid Moment Tensor (GCMT) are adopted to regress the relationships using the orthogonal regression method. The obtained relationships are as follows: MW=0.64+0.87MS; MW=1.16+0.75ML. Therefore, in China, if the moment magnitude of an earthquake is not reported by any agency in the world, we can use the equations mentioned above for converting ML to MW and MS to MW. These relationships are very important, because they will allow the China earthquake catalogs to be used more effectively for seismic hazard analysis, earthquake prediction, and other seismology research. We also computed the relationships of and (where Mo is the seismic moment) by linear regression using the Global Centroid Moment Tensor. The obtained relationships are as follows: logMo=18.21+1.05ML; logMo=17.04+1.32MS. This formula can be used by seismologists to convert the ML/MS of Chinese mainland events into their seismic moments.

Prospective Association Between Negative Life Events and Initiation of Sexual Intercourse: The Influence of Family Structure and Family Income

PubMed Central

Oman, Roy F.; Vesely, Sara K.; Aspy, Cheryl B.; Tolma, Eleni L.; John, Robert

2015-01-01

Objectives. We examined the prospective association between negative life events and time to initiation of sexual intercourse and the influence of family structure and family income on this association. Methods. We followed up a randomly selected sample (n = 649) of ethnically diverse parents and their children aged 12 to 17 years over a 5-year period. We conducted Cox proportional hazards regression analysis to examine the relation between negative life events and time to initiation of sexual intercourse. Family structure and family income were assessed as confounders. Results. Negative life events were significant predictors of time to initiation of sexual intercourse in adolescents. After controlling for demographic variables, youths reporting 1 negative life event had a hazard of initiation of sexual intercourse 1.40 times greater and youths reporting 2 or more negative life events had a hazard of initiation of sexual intercourse 1.61 times greater compared with youths reporting no negative life events. Family structure and family income were not significant confounders of the relation between initiation of sexual intercourse and negative life events. Conclusions. Interventions to prevent initiation of sexual intercourse should focus on youths with recent negative life events, regardless of family income and structure. PMID:25602885

A FORTRAN program for multivariate survival analysis on the personal computer.

PubMed

Mulder, P G

1988-01-01

In this paper a FORTRAN program is presented for multivariate survival or life table regression analysis in a competing risks' situation. The relevant failure rate (for example, a particular disease or mortality rate) is modelled as a log-linear function of a vector of (possibly time-dependent) explanatory variables. The explanatory variables may also include the variable time itself, which is useful for parameterizing piecewise exponential time-to-failure distributions in a Gompertz-like or Weibull-like way as a more efficient alternative to Cox's proportional hazards model. Maximum likelihood estimates of the coefficients of the log-linear relationship are obtained from the iterative Newton-Raphson method. The program runs on a personal computer under DOS; running time is quite acceptable, even for large samples.

Multivariate Models for Prediction of Human Skin Sensitization ...

EPA Pesticide Factsheets

One of the lnteragency Coordinating Committee on the Validation of Alternative Method's (ICCVAM) top priorities is the development and evaluation of non-animal approaches to identify potential skin sensitizers. The complexity of biological events necessary to produce skin sensitization suggests that no single alternative method will replace the currently accepted animal tests. ICCVAM is evaluating an integrated approach to testing and assessment based on the adverse outcome pathway for skin sensitization that uses machine learning approaches to predict human skin sensitization hazard. We combined data from three in chemico or in vitro assays - the direct peptide reactivity assay (DPRA), human cell line activation test (h-CLAT) and KeratinoSens TM assay - six physicochemical properties and an in silico read-across prediction of skin sensitization hazard into 12 variable groups. The variable groups were evaluated using two machine learning approaches , logistic regression and support vector machine, to predict human skin sensitization hazard. Models were trained on 72 substances and tested on an external set of 24 substances. The six models (three logistic regression and three support vector machine) with the highest accuracy (92%) used: (1) DPRA, h-CLAT and read-across; (2) DPRA, h-CLAT, read-across and KeratinoSens; or (3) DPRA, h-CLAT, read-across, KeratinoSens and log P. The models performed better at predicting human skin sensitization hazard than the murine

Trends in hazardous trace metal concentrations in aerosols collected in Beijing, China from 2001 to 2006.

PubMed

Okuda, Tomoaki; Katsuno, Masayuki; Naoi, Daisuke; Nakao, Shunsuke; Tanaka, Shigeru; He, Kebin; Ma, Yongliang; Lei, Yu; Jia, Yingtao

2008-06-01

Daily observations of hazardous trace metal concentrations in aerosols in Beijing, China were made in the period from 2001 to 2006. We considered coal combustion as a major source of some anthropogenic metals by achieving a correlation analysis and by investigating enrichment factors and relative composition of metals. A possible extra source of some specific metals, such as Cu and Sb, was brake abrasion particles, however, we did not think the transport-related particle was a major source for the hazardous anthropogenic metals even though they could originate from vehicle exhaust and brake/tire abrasion particles. A time-trend model was used to describe temporal variations of chemical constituent concentrations during the five-year period. Several crustal elements, such as Al, Ti, V, Cr, Mn, Fe, and Co, did not show clear increases, with annual rates of change of -15.2% to 3.6%. On the other hand, serious increasing trends were noted from several hazardous trace metals. Cu, Zn, As, Cd, and Pb, which are derived mainly from anthropogenic sources, such as coal combustion, showed higher annual rate of change (4.9-19.8%, p<0.001) according to the regression model. In particular, the Cd and Pb concentrations increased remarkably. We hypothesize that the trend towards increasing concentrations of metals in the air reflects a change that has occurred in the process of burning coal, whereby the use of higher temperatures for coal combustion has resulted in increased emissions of these metals. The increasing use of low-rank coal may also explain the observed trends. In addition, nonferrous metal smelters are considered as a potential, albeit minor, reason for the increasing atmospheric concentrations of anthropogenic hazardous metals in Beijing city.

Southern Dietary Pattern is Associated with Hazard of Acute Coronary Heart Disease in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study

PubMed Central

Shikany, James M.; Safford, Monika M.; Newby, P. K.; Durant, Raegan W.; Brown, Todd M.; Judd, Suzanne E.

2015-01-01

Background The association of overall diet, as characterized by dietary patterns, with risk of incident acute coronary heart disease (CHD) has not been studied extensively in samples including sociodemographic and regional diversity. Methods and Results We used data from 17,418 participants in Reasons for Geographic and Racial Differences in Stroke (REGARDS), a national, population-based, longitudinal study of white and black adults aged ≥45 years, enrolled from 2003-2007. We derived dietary patterns with factor analysis, and used Cox proportional hazards regression to examine hazard of incident acute CHD events – nonfatal myocardial infarction and acute CHD death – associated with quartiles of consumption of each pattern, adjusted for various levels of covariates. Five primary dietary patterns emerged: Convenience, Plant-based, Sweets, Southern, and Alcohol and Salad. A total of 536 acute CHD events occurred over a median (IQR) 5.8 (2.1) years of follow-up. After adjustment for sociodemographics, lifestyle factors, and energy intake, highest consumers of the Southern pattern (characterized by added fats, fried food, eggs, organ and processed meats, and sugar-sweetened beverages) experienced a 56% higher hazard of acute CHD (comparing quartile 4 to quartile 1: HR = 1.56; 95% CI: 1.17, 2.08; P for trend across quartiles = 0.003). Adding anthropometric and medical history variables to the model attenuated the association somewhat (HR = 1.37; 95% CI: 1.01, 1.85; P = 0.036). Conclusions A dietary pattern characteristic of the southern US was associated with greater hazard of CHD in this sample of white and black adults in diverse regions of the US. PMID:26260732

Impact of Time to Treatment Initiation in Patients with Human Papillomavirus-positive and -negative Oropharyngeal Squamous Cell Carcinoma.

PubMed

Grønhøj, C; Jensen, D; Dehlendorff, C; Nørregaard, C; Andersen, E; Specht, L; Charabi, B; von Buchwald, C

2018-06-01

The distinct difference in disease phenotype of human papillomavirus-positive (HPV+) and -negative (HPV-) oropharyngeal squamous cell cancer (OPSCC) patients might also be apparent when assessing the effect of time to treatment initiation (TTI). We assessed the overall survival and progression-free survival (PFS) effect from increasing TTI for HPV+ and HPV- OPSCC patients. We examined patients who received curative-intended therapy for OPSCC in eastern Denmark between 2000 and 2014. TTI was the number of days from diagnosis to the initiation of curative treatment. Overall survival and PFS were measured from the start of treatment and estimated with the Kaplan-Meier estimator. Hazard ratios and 95% confidence intervals were estimated with Cox proportional hazard regression. At a median follow-up of 3.6 years (interquartile range 1.86-6.07 years), 1177 patients were included (59% HPV+). In the adjusted analysis for the HPV+ and HPV- patient population, TTI influenced overall survival and PFS, most evident in the HPV- group, where TTI >60 days statistically significantly influenced overall survival but not PFS (overall survival: hazard ratio 1.60; 95% confidence interval 1.04-2.45; PFS: hazard ratio 1.46; 95% confidence interval 0.96-2.22). For patients with a TTI >60 days in the HPV+ group, TTI affected overall survival and PFS similarly, with slightly lower hazard ratio estimates of 1.44 (95% confidence interval 0.83-2.51) and 1.15 (95% confidence interval 0.70-1.88), respectively. For patients treated for a HPV+ or HPV- OPSCC, TTI affects outcome, with the strongest effect for overall survival among HPV- patients. Reducing TTI is an important tool to improve the prognosis. Copyright © 2018. Published by Elsevier Ltd.

Determinants of the lethality of climate-related disasters in the Caribbean Community (CARICOM): a cross-country analysis

PubMed Central

Andrewin, Aisha N.; Rodriguez-Llanes, Jose M.; Guha-Sapir, Debarati

2015-01-01

Floods and storms are climate-related hazards posing high mortality risk to Caribbean Community (CARICOM) nations. However risk factors for their lethality remain untested. We conducted an ecological study investigating risk factors for flood and storm lethality in CARICOM nations for the period 1980–2012. Lethality - deaths versus no deaths per disaster event- was the outcome. We examined biophysical and social vulnerability proxies and a decadal effect as predictors. We developed our regression model via multivariate analysis using a generalized logistic regression model with quasi-binomial distribution; removal of multi-collinear variables and backward elimination. Robustness was checked through subset analysis. We found significant positive associations between lethality, percentage of total land dedicated to agriculture (odds ratio [OR] 1.032; 95% CI: 1.013–1.053) and percentage urban population (OR 1.029, 95% CI 1.003–1.057). Deaths were more likely in the 2000–2012 period versus 1980–1989 (OR 3.708, 95% CI 1.615–8.737). Robustness checks revealed similar coefficients and directions of association. Population health in CARICOM nations is being increasingly impacted by climate-related disasters connected to increasing urbanization and land use patterns. Our findings support the evidence base for setting sustainable development goals (SDG). PMID:26153115

The impact of hyperglycemia on survival in glioblastoma: A systematic review and meta-analysis.

PubMed

Lu, Victor M; Goyal, Anshit; Vaughan, Lachlin S; McDonald, Kerrie L

2018-07-01

In the management of glioblastoma (GBM), there is a considerable predisposition to hyperglycemia due to significant integration of corticosteroid therapy to treat predictable clinical sequelae following diagnosis and treatment. The aim of this study was to quantify effect of hyperglycemia during the management of GBM on overall survival (OS). Searches of seven electronic databases from inception to January 2018 were conducted following Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. There were 1475 articles identified for screening. Prognostic hazard ratios (HRs) derived from multivariate regression analysis were extracted, and analyzed using meta-analysis of proportions and linear regression. Six observational studies reporting prognostic HRs in 10 cohorts were included. They described 1481 GBM diagnoses, all surveyed for hyperglycemia during management. Hyperglycemia was found to confer a statistically significant poorer OS outcome (HR, 1.671; p < 0.001). This trend and its significance was not modified by study year, size or proportion of pre-diagnostic diabetes mellitus. Hyperglycemia in GBM is an independent poor prognostic factor for OS. Heterogeneity in clinical course limits inter-study comparability. Future, prospective, randomized studies will validate the findings of this study, and ascertain the potential benefit of more rigorous monitoring for hyperglycemia and glycemic control. Copyright © 2018 Elsevier B.V. All rights reserved.

78 FR 69604 - Current Good Manufacturing Practice and Hazard Analysis and Risk-Based Preventive Controls for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-20

... Manufacturing Practice and Hazard Analysis and Risk- Based Preventive Controls for Human Food; Extension of... Hazard Analysis and Risk- Based Preventive Controls for Human Food'' and its information collection... Manufacturing Practice and Hazard Analysis and Risk-Based Preventive Controls for Human Food.'' IV. How To...

Applying machine-learning techniques to Twitter data for automatic hazard-event classification.

NASA Astrophysics Data System (ADS)

Filgueira, R.; Bee, E. J.; Diaz-Doce, D.; Poole, J., Sr.; Singh, A.

2017-12-01

The constant flow of information offered by tweets provides valuable information about all sorts of events at a high temporal and spatial resolution. Over the past year we have been analyzing in real-time geological hazards/phenomenon, such as earthquakes, volcanic eruptions, landslides, floods or the aurora, as part of the GeoSocial project, by geo-locating tweets filtered by keywords in a web-map. However, not all the filtered tweets are related with hazard/phenomenon events. This work explores two classification techniques for automatic hazard-event categorization based on tweets about the "Aurora". First, tweets were filtered using aurora-related keywords, removing stop words and selecting the ones written in English. For classifying the remaining between "aurora-event" or "no-aurora-event" categories, we compared two state-of-art techniques: Support Vector Machine (SVM) and Deep Convolutional Neural Networks (CNN) algorithms. Both approaches belong to the family of supervised learning algorithms, which make predictions based on labelled training dataset. Therefore, we created a training dataset by tagging 1200 tweets between both categories. The general form of SVM is used to separate two classes by a function (kernel). We compared the performance of four different kernels (Linear Regression, Logistic Regression, Multinomial Naïve Bayesian and Stochastic Gradient Descent) provided by Scikit-Learn library using our training dataset to build the SVM classifier. The results shown that the Logistic Regression (LR) gets the best accuracy (87%). So, we selected the SVM-LR classifier to categorise a large collection of tweets using the "dispel4py" framework.Later, we developed a CNN classifier, where the first layer embeds words into low-dimensional vectors. The next layer performs convolutions over the embedded word vectors. Results from the convolutional layer are max-pooled into a long feature vector, which is classified using a softmax layer. The CNN's accuracy is lower (83%) than the SVM-LR, since the algorithm needs a bigger training dataset to increase its accuracy. We used TensorFlow framework for applying CNN classifier to the same collection of tweets.In future we will modify both classifiers to work with other geo-hazards, use larger training datasets and apply them in real-time.

Drought impact functions as intermediate step towards drought damage assessment

NASA Astrophysics Data System (ADS)

Bachmair, Sophie; Svensson, Cecilia; Prosdocimi, Ilaria; Hannaford, Jamie; Helm Smith, Kelly; Svoboda, Mark; Stahl, Kerstin

2016-04-01

While damage or vulnerability functions for floods and seismic hazards have gained considerable attention, there is comparably little knowledge on drought damage or loss. On the one hand this is due to the complexity of the drought hazard affecting different domains of the hydrological cycle and different sectors of human activity. Hence, a single hazard indicator is likely not able to fully capture this multifaceted hazard. On the other hand, drought impacts are often non-structural and hard to quantify or monetize. Examples are impaired navigability of streams, restrictions on domestic water use, reduced hydropower production, reduced tree growth, and irreversible deterioration/loss of wetlands. Apart from reduced crop yield, data about drought damage or loss with adequate spatial and temporal resolution is scarce, making the development of drought damage functions difficult. As an intermediate step towards drought damage functions we exploit text-based reports on drought impacts from the European Drought Impact report Inventory and the US Drought Impact Reporter to derive surrogate information for drought damage or loss. First, text-based information on drought impacts is converted into timeseries of absence versus presence of impacts, or number of impact occurrences. Second, meaningful hydro-meteorological indicators characterizing drought intensity are identified. Third, different statistical models are tested as link functions relating drought hazard indicators with drought impacts: 1) logistic regression for drought impacts coded as binary response variable; and 2) mixture/hurdle models (zero-inflated/zero-altered negative binomial regression) and an ensemble regression tree approach for modeling the number of drought impact occurrences. Testing the predictability of (number of) drought impact occurrences based on cross-validation revealed a good agreement between observed and modeled (number of) impacts for regions at the scale of federal states or provinces with good data availability. Impact functions representing localized drought impacts are more challenging to construct given that less data is available, yet may provide information that more directly addresses stakeholders' needs. Overall, our study contributes insights into how drought intensity translates into ecological and socioeconomic impacts, and how such information may be used for enhancing drought monitoring and early warning.

Charlson comorbidity index as a predictor of periodontal disease in elderly participants

PubMed Central

2018-01-01

Purpose This study investigated the validity of the Charlson comorbidity index (CCI) as a predictor of periodontal disease (PD) over a 12-year period. Methods Nationwide representative samples of 149,785 adults aged ≥60 years with PD (International Classification of Disease, 10th revision [ICD-10], K052–K056) were derived from the National Health Insurance Service-Elderly Cohort during 2002–2013. The degree of comorbidity was measured using the CCI (grade 0–6), including 17 diseases weighted on the basis of their association with mortality, and data were analyzed using multivariate Cox proportional-hazards regression in order to investigate the associations of comorbid diseases (CDs) with PD. Results The multivariate Cox regression analysis with adjustment for sociodemographic factors (sex, age, household income, insurance status, residence area, and health status) and CDs (acute myocardial infarction, congestive heart failure, peripheral vascular disease, cerebral vascular accident, dementia, pulmonary disease, connective tissue disorders, peptic ulcer, liver disease, diabetes, diabetes complications, paraplegia, renal disease, cancer, metastatic cancer, severe liver disease, and human immunodeficiency virus [HIV]) showed that the CCI in elderly comorbid participants was significantly and positively correlated with the presence of PD (grade 1: hazard ratio [HR], 1.11; P<0.001; grade ≥2: HR, 1.12, P<0.001). Conclusions We demonstrated that a higher CCI was a significant predictor of greater risk for PD in the South Korean elderly population. PMID:29770238

Clinical Impact of Emphysema Evaluated by High-Resolution Computed Tomography on Idiopathic Pulmonary Fibrosis Diagnosed by Surgical Lung Biopsy.

PubMed

Kohashi, Yasuo; Arai, Toru; Sugimoto, Chikatoshi; Tachibana, Kazunobu; Akira, Masanori; Kitaichi, Masanori; Hayashi, Seiji; Inoue, Yoshikazu

2016-01-01

The prognosis of combined cases of pulmonary fibrosis and emphysema is unresolved partially because radiological differentiation between usual interstitial pneumonia and nonspecific interstitial pneumonia is difficult in coexisting emphysema cases. The purpose of this study was to clarify the clinical impact of emphysema on the survival of patients with idiopathic pulmonary fibrosis (IPF). One hundred and seven patients with interstitial lung diseases were diagnosed by surgical lung biopsies between 2006 and 2012, and 47 patients were diagnosed with IPF through multidisciplinary discussion. Emphysema on high-resolution computed tomography scans was evaluated semiquantitatively by visual scoring. Eight out of the 47 IPF patients showed a higher emphysema score (>3) and were diagnosed to have IPF-emphysema. The median survival time of patients with IPF-emphysema (1,734 days) from the initial diagnosis was significantly shorter than that of patients with IPF alone (2,229 days) by Kaplan-Meier analysis (p = 0.007, log-rank test). Univariate Cox proportional hazard regression analyses revealed that a higher total emphysema score (>3.0) was a significantly poor prognostic factor in addition to Krebs von den Lungen-6, surfactant protein-D, arterial oxygen tension, percent forced vital capacity, and percent diffusing capacity of carbon monoxide (%DLCO). Multivariate Cox proportional hazard regression analyses with the stepwise method showed that higher total emphysema score (>3) and %DLCO were significantly poor prognostic factors. The prognosis of IPF-emphysema was significantly worse than that of IPF alone. © 2016 S. Karger AG, Basel.

Progress of statistical analysis in biomedical research through the historical review of the development of the Framingham score.

PubMed

Ignjatović, Aleksandra; Stojanović, Miodrag; Milošević, Zoran; Anđelković Apostolović, Marija

2017-12-02

The interest in developing risk models in medicine not only is appealing, but also associated with many obstacles in different aspects of predictive model development. Initially, the association of biomarkers or the association of more markers with the specific outcome was proven by statistical significance, but novel and demanding questions required the development of new and more complex statistical techniques. Progress of statistical analysis in biomedical research can be observed the best through the history of the Framingham study and development of the Framingham score. Evaluation of predictive models comes from a combination of the facts which are results of several metrics. Using logistic regression and Cox proportional hazards regression analysis, the calibration test, and the ROC curve analysis should be mandatory and eliminatory, and the central place should be taken by some new statistical techniques. In order to obtain complete information related to the new marker in the model, recently, there is a recommendation to use the reclassification tables by calculating the net reclassification index and the integrated discrimination improvement. Decision curve analysis is a novel method for evaluating the clinical usefulness of a predictive model. It may be noted that customizing and fine-tuning of the Framingham risk score initiated the development of statistical analysis. Clinically applicable predictive model should be a trade-off between all abovementioned statistical metrics, a trade-off between calibration and discrimination, accuracy and decision-making, costs and benefits, and quality and quantity of patient's life.

[Value of the albumin to globulin ratio in predicting severity and prognosis in myasthenia gravis patients].

PubMed

Yang, D H; Su, Z Q; Chen, Y; Chen, Z B; Ding, Z N; Weng, Y Y; Li, J; Li, X; Tong, Q L; Han, Y X; Zhang, X

2016-03-08

To assess the predictive value of the albumin to globulin ratio (AGR) in evaluation of disease severity and prognosis in myasthenia gravis patients. A total of 135 myasthenia gravis (MG) patients were enrolled between February 2009 and March 2015. The AGR was detected on the first day of hospitalization and ranked from lowest to highest, and the patients were divided into three equal tertiles according to the AGR values, which were T1 (AGR <1.34), T2 (1.34≤AGR≤1.53) and T3 (AGR>1.53). The Kaplan-Meier curve was used to evaluate the prognostic value of AGR. Cox model analysis was used to evaluate the relevant factors. Multivariate Logistic regression analysis was used to find the predictors of myasthenia crisis during hospitalization. The median length of hospital stay for each tertile was: for the T1 21 days (15-35.5), T2 18 days (14-27.5), and T3 16 days (12-22.5) (P<0.01), and Kaplan-Meier curves showed significant difference among the three groups. In the univariate model, serum albumin, creatinine, AGR and MGFA clinical classification were related to prognosis of myasthenia gravis. At the multivariate Cox regression analysis, the AGR (P<0.001) and MGFA clinical classification (P<0.001) were independent predictive factors of disease severity and prognosis in myasthenia gravis patients. Respectively, the hazard ratio (HR) were 4.655 (95% CI: 2.355-9.202) and 0.596 (95% CI: 0.492-0.723). Multivariate Logistic regression analysis showed the AGR (P<0.001) and MGFA clinical classification were related to myasthenia crisis. The AGR may represent a simple, potentially useful predictive biomarker for evaluating the disease severity and prognosis of patients with myasthenia gravis.

Quantile Regression for Recurrent Gap Time Data

PubMed Central

Luo, Xianghua; Huang, Chiung-Yu; Wang, Lan

2014-01-01

Summary Evaluating covariate effects on gap times between successive recurrent events is of interest in many medical and public health studies. While most existing methods for recurrent gap time analysis focus on modeling the hazard function of gap times, a direct interpretation of the covariate effects on the gap times is not available through these methods. In this article, we consider quantile regression that can provide direct assessment of covariate effects on the quantiles of the gap time distribution. Following the spirit of the weighted risk-set method by Luo and Huang (2011, Statistics in Medicine 30, 301–311), we extend the martingale-based estimating equation method considered by Peng and Huang (2008, Journal of the American Statistical Association 103, 637–649) for univariate survival data to analyze recurrent gap time data. The proposed estimation procedure can be easily implemented in existing software for univariate censored quantile regression. Uniform consistency and weak convergence of the proposed estimators are established. Monte Carlo studies demonstrate the effectiveness of the proposed method. An application to data from the Danish Psychiatric Central Register is presented to illustrate the methods developed in this article. PMID:23489055

Semiparametric regression analysis of interval-censored competing risks data.

PubMed

Mao, Lu; Lin, Dan-Yu; Zeng, Donglin

2017-09-01

Interval-censored competing risks data arise when each study subject may experience an event or failure from one of several causes and the failure time is not observed directly but rather is known to lie in an interval between two examinations. We formulate the effects of possibly time-varying (external) covariates on the cumulative incidence or sub-distribution function of competing risks (i.e., the marginal probability of failure from a specific cause) through a broad class of semiparametric regression models that captures both proportional and non-proportional hazards structures for the sub-distribution. We allow each subject to have an arbitrary number of examinations and accommodate missing information on the cause of failure. We consider nonparametric maximum likelihood estimation and devise a fast and stable EM-type algorithm for its computation. We then establish the consistency, asymptotic normality, and semiparametric efficiency of the resulting estimators for the regression parameters by appealing to modern empirical process theory. In addition, we show through extensive simulation studies that the proposed methods perform well in realistic situations. Finally, we provide an application to a study on HIV-1 infection with different viral subtypes. © 2017, The International Biometric Society.

Hazard Analysis for Pneumatic Flipper Suitport/Z-1 Manned Evaluation, Chamber B, Building 32. Revision: Basic

NASA Technical Reports Server (NTRS)

2012-01-01

One of the characteristics of an effective safety program is the recognition and control of hazards before mishaps or failures occur. Conducting potentially hazardous tests necessitates a thorough hazard analysis in order to protect our personnel from injury and our equipment from damage. The purpose of this hazard analysis is to define and address the potential hazards and controls associated with the Z1 Suit Port Test in Chamber B located in building 32, and to provide the applicable team of personnel with the documented results. It is imperative that each member of the team be familiar with the hazards and controls associated with his/her particular tasks, assignments, and activities while interfacing with facility test systems, equipment, and hardware. The goal of this hazard analysis is to identify all hazards that have the potential to harm personnel and/or damage facility equipment, flight hardware, property, or harm the environment. This analysis may also assess the significance and risk, when applicable, of lost test objectives when substantial monetary value is involved. The hazards, causes, controls, verifications, and risk assessment codes have been documented on the hazard analysis work sheets in appendix A of this document. The preparation and development of this report is in accordance with JPR 1700.1, JSC Safety and Health Handbook.

The Management Standards Indicator Tool and evaluation of burnout.

PubMed

Ravalier, J M; McVicar, A; Munn-Giddings, C

2013-03-01

Psychosocial hazards in the workplace can impact upon employee health. The UK Health and Safety Executive's (HSE) Management Standards Indicator Tool (MSIT) appears to have utility in relation to health impacts but we were unable to find studies relating it to burnout. To explore the utility of the MSIT in evaluating risk of burnout assessed by the Maslach Burnout Inventory-General Survey (MBI-GS). This was a cross-sectional survey of 128 borough council employees. MSIT data were analysed according to MSIT and MBI-GS threshold scores and by using multivariate linear regression with MBI-GS factors as dependent variables. MSIT factor scores were gradated according to categories of risk of burnout according to published MBI-GS thresholds, and identified priority workplace concerns as demands, relationships, role and change. These factors also featured as significant independent variables, with control, in outcomes of the regression analysis. Exhaustion was associated with demands and control (adjusted R (2) = 0.331); cynicism was associated with change, role and demands (adjusted R (2) =0.429); and professional efficacy was associated with managerial support, role, control and demands (adjusted R (2) = 0.413). MSIT analysis generally has congruence with MBI-GS assessment of burnout. The identification of control within regression models but not as a priority concern in the MSIT analysis could suggest an issue of the setting of the MSIT thresholds for this factor, but verification requires a much larger study. Incorporation of relationship, role and change into the MSIT, missing from other conventional tools, appeared to add to its validity.

Drought Patterns Forecasting using an Auto-Regressive Logistic Model

NASA Astrophysics Data System (ADS)

del Jesus, M.; Sheffield, J.; Méndez Incera, F. J.; Losada, I. J.; Espejo, A.

2014-12-01

Drought is characterized by a water deficit that may manifest across a large range of spatial and temporal scales. Drought may create important socio-economic consequences, many times of catastrophic dimensions. A quantifiable definition of drought is elusive because depending on its impacts, consequences and generation mechanism, different water deficit periods may be identified as a drought by virtue of some definitions but not by others. Droughts are linked to the water cycle and, although a climate change signal may not have emerged yet, they are also intimately linked to climate.In this work we develop an auto-regressive logistic model for drought prediction at different temporal scales that makes use of a spatially explicit framework. Our model allows to include covariates, continuous or categorical, to improve the performance of the auto-regressive component.Our approach makes use of dimensionality reduction (principal component analysis) and classification techniques (K-Means and maximum dissimilarity) to simplify the representation of complex climatic patterns, such as sea surface temperature (SST) and sea level pressure (SLP), while including information on their spatial structure, i.e. considering their spatial patterns. This procedure allows us to include in the analysis multivariate representation of complex climatic phenomena, as the El Niño-Southern Oscillation. We also explore the impact of other climate-related variables such as sun spots. The model allows to quantify the uncertainty of the forecasts and can be easily adapted to make predictions under future climatic scenarios. The framework herein presented may be extended to other applications such as flash flood analysis, or risk assessment of natural hazards.

Statistical analysis of life history calendar data.

PubMed

Eerola, Mervi; Helske, Satu

2016-04-01

The life history calendar is a data-collection tool for obtaining reliable retrospective data about life events. To illustrate the analysis of such data, we compare the model-based probabilistic event history analysis and the model-free data mining method, sequence analysis. In event history analysis, we estimate instead of transition hazards the cumulative prediction probabilities of life events in the entire trajectory. In sequence analysis, we compare several dissimilarity metrics and contrast data-driven and user-defined substitution costs. As an example, we study young adults' transition to adulthood as a sequence of events in three life domains. The events define the multistate event history model and the parallel life domains in multidimensional sequence analysis. The relationship between life trajectories and excess depressive symptoms in middle age is further studied by their joint prediction in the multistate model and by regressing the symptom scores on individual-specific cluster indices. The two approaches complement each other in life course analysis; sequence analysis can effectively find typical and atypical life patterns while event history analysis is needed for causal inquiries. © The Author(s) 2012.

78 FR 24691 - Current Good Manufacturing Practice and Hazard Analysis and Risk-Based Preventive Controls for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-26

... Manufacturing Practice and Hazard Analysis and Risk- Based Preventive Controls for Human Food; Extension of... Manufacturing Practice and Hazard Analysis and Risk-Based Preventive Controls for Human Food'' that appeared in... Manufacturing Practice and Hazard Analysis and Risk-Based Preventive Controls for Human Food'' with a 120-day...

Site specific seismic hazard analysis and determination of response spectra of Kolkata for maximum considered earthquake

NASA Astrophysics Data System (ADS)

Shiuly, Amit; Sahu, R. B.; Mandal, Saroj

2017-06-01

This paper presents site specific seismic hazard analysis of Kolkata city, former capital of India and present capital of state West Bengal, situated on the world’s largest delta island, Bengal basin. For this purpose, peak ground acceleration (PGA) for a maximum considered earthquake (MCE) at bedrock level has been estimated using an artificial neural network (ANN) based attenuation relationship developed on the basis of synthetic ground motion data for the region. Using the PGA corresponding to the MCE, a spectrum compatible acceleration time history at bedrock level has been generated by using a wavelet based computer program, WAVEGEN. This spectrum compatible time history at bedrock level has been converted to the same at surface level using SHAKE2000 for 144 borehole locations in the study region. Using the predicted values of PGA and PGV at the surface, corresponding contours for the region have been drawn. For the MCE, the PGA at bedrock level of Kolkata city has been obtained as 0.184 g, while that at the surface level varies from 0.22 g to 0.37 g. Finally, Kolkata has been subdivided into eight seismic subzones, and for each subzone a response spectrum equation has been derived using polynomial regression analysis. This will be very helpful for structural and geotechnical engineers to design safe and economical earthquake resistant structures.

Building and validation of a prognostic model for predicting extracorporeal circuit clotting in patients with continuous renal replacement therapy.

PubMed

Fu, Xia; Liang, Xinling; Song, Li; Huang, Huigen; Wang, Jing; Chen, Yuanhan; Zhang, Li; Quan, Zilin; Shi, Wei

2014-04-01

To develop a predictive model for circuit clotting in patients with continuous renal replacement therapy (CRRT). A total of 425 cases were selected. 302 cases were used to develop a predictive model of extracorporeal circuit life span during CRRT without citrate anticoagulation in 24 h, and 123 cases were used to validate the model. The prediction formula was developed using multivariate Cox proportional-hazards regression analysis, from which a risk score was assigned. The mean survival time of the circuit was 15.0 ± 1.3 h, and the rate of circuit clotting was 66.6 % during 24 h of CRRT. Five significant variables were assigned a predicting score according to the regression coefficient: insufficient blood flow, no anticoagulation, hematocrit ≥0.37, lactic acid of arterial blood gas analysis ≤3 mmol/L and APTT < 44.2 s. The Hosmer-Lemeshow test showed no significant difference between the predicted and actual circuit clotting (R (2) = 0.232; P = 0.301). A risk score that includes the five above-mentioned variables can be used to predict the likelihood of extracorporeal circuit clotting in patients undergoing CRRT.

Prevalence of Depressive Symptoms and Related Factors in Korean Employees: The Third Korean Working Conditions Survey (2011).

PubMed

Park, Ji Nam; Han, Mi Ah; Park, Jong; Ryu, So Yeon

2016-04-14

The aim of this study was to analyze the association between general working conditions and depressive symptoms among Korean employees. The target population of the study was native employees nationwide who were at least 15 years old, and 50,032 such individuals were enrolled in the study. Depressive symptoms was assessed using the WHO-5 wellbeing index. Associations between general characteristics, job-related characteristics, work environment, and depressive symptoms were tested using chi-square tests, t-tests, and multiple logistic regression analysis. The prevalence of depressive symptoms was 39% (40.7% in males and 36.5% in females). Multiple regression analysis revealed that male subjects, older subjects, subjects with higher education status, subjects with lower monthly income, current smokers, and frequent drinkers were more likely to have depressive symptoms. In addition, longer weekly work hours, occupation type (skilled, unskilled, operative, or economic sector), shift work, working to tight deadlines, exposure to stress at work, and hazard exposure were associated with depressive symptoms. This representative study will be a guide to help manage depression among Korean employees. We expect that further research will identify additional causal relationships between general or specific working conditions and depression.

A Concept-Wide Association Study of Clinical Notes to Discover New Predictors of Kidney Failure.

PubMed

Singh, Karandeep; Betensky, Rebecca A; Wright, Adam; Curhan, Gary C; Bates, David W; Waikar, Sushrut S

2016-12-07

Identifying predictors of kidney disease progression is critical toward the development of strategies to prevent kidney failure. Clinical notes provide a unique opportunity for big data approaches to identify novel risk factors for disease. We used natural language processing tools to extract concepts from the preceding year's clinical notes among patients newly referred to a tertiary care center's outpatient nephrology clinics and retrospectively evaluated these concepts as predictors for the subsequent development of ESRD using proportional subdistribution hazards (competing risk) regression. The primary outcome was time to ESRD, accounting for a competing risk of death. We identified predictors from univariate and multivariate (adjusting for Tangri linear predictor) models using a 5% threshold for false discovery rate (q value <0.05). We included all patients seen by an adult outpatient nephrologist between January 1, 2004 and June 18, 2014 and excluded patients seen only by transplant nephrology, with preexisting ESRD, with fewer than five clinical notes, with no follow-up, or with no baseline creatinine values. Among the 4013 patients selected in the final study cohort, we identified 960 concepts in the unadjusted analysis and 885 concepts in the adjusted analysis. Novel predictors identified included high-dose ascorbic acid (adjusted hazard ratio, 5.48; 95% confidence interval, 2.80 to 10.70; q<0.001) and fast food (adjusted hazard ratio, 4.34; 95% confidence interval, 2.55 to 7.40; q<0.001). Novel predictors of human disease may be identified using an unbiased approach to analyze text from the electronic health record. Copyright © 2016 by the American Society of Nephrology.

Assessment of the Risk of Fractures Because of Service on Diesel Submarines: A Retrospective Cohort Study.

PubMed

Saad, Amit; Kala, Carmel; Ohayon, Sharon; Feldman, Lior; Galili, Eran; Yanir, Yoav; Nemet, Dan; Netzer, Itamar

2015-07-01

Submariners are known to have decreased bone mass following periods of long submersion. We examined whether this produces a higher predilection to fractures. This is a retrospective cohort study. Data were collected from the computerized medical records of 457 consecutive submariners (serving 1091.42 man-years). The control group included 3,219 consecutive sailors, (serving 5845.04 man-years). Groups were stratified according to age at induction, body mass index, place of birth, and status of service (i.e., compulsory versus professional). Analysis of fracture incidence and comparison of proportions between the groups was conducted using χ(2) tests and Fisher's exact test. The hazard ratio for fractures was performed using a survival analysis regression model for each group (Cox Proportional Hazard Model). Nineteen submariners (4.2%) and 94 sailors (2.9%) were shown to have fractures during their service (RR = 1.42, p = 0.15). A Cox proportional hazard model was employed. No statistically significant difference was found between the 2 groups (HR = 1.037, p = 0.89). No correlation was found between length of service and risk of fracture. Most fractures suffered by submariners occurred outside their work environment. Submariners are repeatedly exposed to prolonged submersions that are deleterious to bone strength. However, no statistically significant difference in the incidence of fractures was found between submariners and surface sailors. This is an important finding for the bone and occupational health of submariners in general. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

Overexpression of Transcobalamin 1 is an Independent Negative Prognosticator in Rectal Cancers Receiving Concurrent Chemoradiotherapy.

PubMed

Lee, Yi-Ying; Wei, Yu-Ching; Tian, Yu-Feng; Sun, Ding-Ping; Sheu, Ming-Jen; Yang, Ching-Chieh; Lin, Li-Ching; Lin, Chen-Yi; Hsing, Chung-Hsi; Li, Wan-Shan; Li, Chien-Feng; Hsieh, Pei-Ling; Lin, Ching-Yih

2017-01-01

Objective: Neoadjuvant concurrent chemoradiotherapy (CCRT) is an increasingly common therapeutic strategy for locally advanced rectal cancer, but stratification of risk and final outcomes remain a major challenge. Transcobalamin 1 (TCN1), a vitamin B12 (cobalamin)-binding protein, regulates cobalamin homeostasis. High expression of TCN1 have been reported in neoplasms such as breast cancer and hepatocellular carcinoma. However, little is known about the relevance of TCN1 to rectal cancer receiving CCRT. This study examined the predictive and prognostic impact of TCN1 expression in patients with rectal cancer following neoadjuvant CCRT. Methods: Through data mining from a published transcriptome of rectal cancers (GSE35452), we identified upregulation of TCN1 gene as the most significantly predicted poor response to CCRT among ion transport-related genes (GO:0006811). We evaluated TCN1 immunohistochemistry and performed an H-score analysis on endoscopic biopsy specimens from 172 rectal cancer patients receiving neoadjuvant CCRT followed by curative surgery. Expression levels of TCN1 were further correlated with clinicopathologic features, therapeutic response, tumor regression grade (TRG) and survivals including metastasis-free survival (MeFS), disease-specific survival (DSS) and recurrent-free survival (LRFS). Results: TCN1 overexpression was significantly related to advanced post-treatment tumor (T3, T4; p <0.001) and nodal status (N1, N2; p <0.001), vascular invasion ( p =0.003) and inferior tumor regression grade ( p < 0.001). In survival analyses, TCN1 overexpression was significantly associated with shorter DSS ( p <0.0001), MeFS ( p =0.0002) and LRFS ( p =0.0001). Furthermore, it remained an independent prognosticator of worse DSS ( p =0.002, hazard ratio=3.344), MeFS ( p =0.021, hazard ratio=3.015) and LRFS ( p =0.037, hazard ratio=3.037) in the multivariate comparison. Conclusion: Overexpression of TCN1 is associated with poor therapeutic response and adverse outcomes in rectal cancer patients receiving CCRT, justifying the potential prognostic value of TCN1 in rectal cancer receiving CCRT.

Brachytherapy Improves Survival in Stage III Endometrial Cancer With Cervical Involvement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bingham, Brian; Orton, Andrew; Boothe, Dustin

Purpose: To evaluate the survival benefit of adding vaginal brachytherapy (BT) to pelvic external beam radiation therapy (EBRT) in women with stage III endometrial cancer. Methods and Materials: The National Cancer Data Base was used to identify patients with stage III endometrial cancer from 2004 to 2013. Only women who received adjuvant EBRT were analyzed. Women were grouped according to receipt of BT. Logistic regression modeling was used to identify predictors of receiving BT. Log–rank statistics were used to compare survival outcomes. Cox proportional hazards modeling was used to evaluate the effect of BT on survival. A propensity score–matched analysismore » was also conducted among women with cervical involvement. Results: We evaluated 12,988 patients with stage III endometrial carcinoma, 39% of whom received EBRT plus BT. Women who received BT were more likely to have endocervical or cervical stromal involvement (odds ratios 2.03 and 1.77; P<.01, respectively). For patients receiving EBRT alone, the 5-year survival was 66% versus 69% with the addition of BT at 5 years (P<.01). Brachytherapy remained significantly predictive of decreased risk of death (hazard ratio 0.86; P<.01) on multivariate Cox regression. The addition of BT to EBRT did not affect survival among women without cervical involvement (P=.84). For women with endocervical or cervical stromal invasion, the addition of BT significantly improved survival (log–rank P<.01). Receipt of EBRT plus BT was associated with improved survival in women with positive and negative surgical margins, and receiving chemotherapy did not alter the benefit of BT. Propensity score–matched analysis results confirmed the benefit of BT among women with cervical involvement (hazard ratio 0.80; P=.01). Conclusions: In this population of women with stage III endometrial cancer the addition of BT to EBRT was associated with an improvement in survival for women with endocervical or cervical stromal invasion.« less

Competing Risk Analysis of Neurologic versus Nonneurologic Death in Patients Undergoing Radiosurgical Salvage After Whole-Brain Radiation Therapy Failure: Who Actually Dies of Their Brain Metastases?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lucas, John T., E-mail: jolucas@wakehealth.edu; Colmer, Hentry G.; White, Lance

Purpose: To estimate the hazard for neurologic (central nervous system, CNS) and nonneurologic (non-CNS) death associated with patient, treatment, and systemic disease status in patients receiving stereotactic radiosurgery after whole-brain radiation therapy (WBRT) failure, using a competing risk model. Patients and Methods: Of 757 patients, 293 experienced recurrence or new metastasis following WBRT. Univariate Cox proportional hazards regression identified covariates for consideration in the multivariate model. Competing risks multivariable regression was performed to estimate the adjusted hazard ratio (aHR) and 95% confidence interval (CI) for both CNS and non-CNS death after adjusting for patient, disease, and treatment factors. The resultantmore » model was converted into an online calculator for ease of clinical use. Results: The cumulative incidence of CNS and non-CNS death at 6 and 12 months was 20.6% and 21.6%, and 34.4% and 35%, respectively. Patients with melanoma histology (relative to breast) (aHR 2.7, 95% CI 1.5-5.0), brainstem location (aHR 2.1, 95% CI 1.3-3.5), and number of metastases (aHR 1.09, 95% CI 1.04-1.2) had increased aHR for CNS death. Progressive systemic disease (aHR 0.55, 95% CI 0.4-0.8) and increasing lowest margin dose (aHR 0.97, 95% CI 0.9-0.99) were protective against CNS death. Patients with lung histology (aHR 1.3, 95% CI 1.1-1.9) and progressive systemic disease (aHR 2.14, 95% CI 1.5-3.0) had increased aHR for non-CNS death. Conclusion: Our nomogram provides individual estimates of neurologic death after salvage stereotactic radiosurgery for patients who have failed prior WBRT, based on histology, neuroanatomical location, age, lowest margin dose, and number of metastases after adjusting for their competing risk of death from other causes.« less

Combined effect of individual and neighbourhood socioeconomic status on mortality of rheumatoid arthritis patients under universal health care coverage system.

PubMed

Chen, Cheng-Hsin; Huang, Kuang-Yung; Wang, Jen-Yu; Huang, Hsien-Bin; Chou, Pesus; Lee, Ching-Chih

2015-02-01

The National Health Insurance program in Taiwan is a public insurance system for the entire population of Taiwan initiated since March 1995. However, the association of socioeconomic status (SES) and prognosis of rheumatoid arthritis (RA) patients under this program has not been identified. Using the National Health Insurance Research Database in Taiwan, we aimed to examine the combined effect of individual and neighbourhood SES on the mortality rates of RA patients under a universal health care coverage system. A study population included patients with RA from 2004 to 2008. The primary end point was the 5-year overall mortality rate. Individual SES was categorized into low, moderate and high levels based on the income-related insurance payment amount. Neighbourhood SES was defined by household income and neighbourhoods were grouped as an 'advantaged' area or a 'disadvantaged' area. The Cox proportional hazards regression model was used to compare outcomes between different SES categories. A two-sided P value < 0.05 was considered statistically significant. Medical data of 23900 RA patients from 2004 to 2008 were reviewed. Analysis of the combined effect of individual SES and neighbourhood SES revealed that 5-year mortality rates were worse among RA patients with a low individual SES compared to those with a high SES (P < 0.001). In the Cox proportional hazards regression model, RA patients with low individual SES in disadvantaged neighbourhoods incurred the highest risk of mortality (Hazard ratio = 1.64; 95% confidence interval, 1.26-2.13, P < 0.001). RA patients with a low SES have a higher overall mortality rate than those with a higher SES, even with a universal health care system. It is crucial that more public policy and health care efforts be put into alleviating the health disadvantages, besides providing treatment payment coverage. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Baseline Quality of Life and Risk of Stroke in the ALLHAT Study (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial).

PubMed

Shams, Tanzila; Auchus, Alexander P; Oparil, Suzanne; Wright, Clinton B; Wright, Jackson; Furlan, Anthony J; Sila, Cathy A; Davis, Barry R; Pressel, Sara; Yamal, Jose-Miguel; Einhorn, Paula T; Lerner, Alan J

2017-11-01

The visual analogue scale is a self-reported, validated tool to measure quality of life (QoL). Our purpose was to determine whether baseline QoL predicted strokes in the ALLHAT study (Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial) and evaluate determinants of poststroke change in QoL. In the ALLHAT study, among the 33 357 patients randomized to treatment arms, 1525 experienced strokes; 1202 (79%) strokes were nonfatal. This study cohort includes 32 318 (97%) subjects who completed the baseline visual analogue scale QoL estimate. QoL was measured on a visual analogue scale and adjusted using a Torrance transformation (transformed QoL [TQoL]). Kaplan-Meier curves and adjusted proportional hazards analyses were used to estimate the effect of TQoL on the risk of stroke, on a continuous scale (0-1) and by quartiles (≤0.81, >0.81≤0.89, >0.89≤0.95, >0.95). We analyzed the change from baseline to first poststroke TQoL using adjusted linear regression. After adjusting for multiple stroke risk factors, the hazard ratio for stroke events for baseline TQoL was 0.93 (95% confidence interval, 0.89-0.98) per 0.1 U increase. The lowest baseline TQoL quartile had a 20% increased stroke risk (hazard ratio=1.20 [95% confidence interval, 1.00-1.44]) compared with the reference highest quartile TQoL. Poststroke TQoL change was significant within all treatment groups ( P ≤0.001). Multivariate regression analysis revealed that baseline TQoL was the strongest predictor of poststroke TQoL with similar results for the untransformed QoL. The lowest baseline TQoL quartile had a 20% higher stroke risk than the highest quartile. Baseline TQoL was the only factor that predicted poststroke change in TQoL. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000542. © 2017 American Heart Association, Inc.

The Prescription Pattern of Chinese Herbal Products That Contain Dang-Qui and Risk of Endometrial Cancer among Tamoxifen-Treated Female Breast Cancer Survivors in Taiwan: A Population-Based Study

PubMed Central

Wu, Chien-Tung; Lai, Jung-Nien; Tsai, Yueh-Ting

2014-01-01

Purpose The increased practice of traditional Chinese medicine worldwide has raised concerns regarding herb-drug interactions. We analyzed the usage of Chinese herbal products containing dang-qui and investigated whether dang-qui therapy increases endometrial cancer risk among tamoxifen-treated breast cancer survivors in Taiwan. Methods All patients newly diagnosed with invasive breast cancer who received tamoxifen treatment from January 1, 1998, to December 31, 2008 were selected from the National Health Insurance Research Database. The usage, frequency of service and type of Chinese herbal products containing dang-qui prescribed across the 31,970 survivors were evaluated. Logistic regression method was employed to estimate the odds ratios for utilization of Chinese herbal products containing dang-qui. Cox proportional hazard regression was performed to calculate the hazard ratio of endometrial cancer associated with dang-qui use within the cohort. Results Almost one in two study subjects had used dang-qui. Among 31,938 tamoxifen-treated breast cancer survivors, 157 cases of subsequent endometrial cancer were identified. The hazard ratio for development of endometrial cancer among breast cancer survivors aged 20–79 years who had taken dang-qui after tamoxifen treatment was decreased compared to survivors who had never used dang-qui (HR: 0.61, 95%CI: 0.44–0.84). To minimise potential confounding factors, women with breast cancer in the reproductive age were excluded from further analysis, and the negative relationship between dang-qui consumption and subsequent endometrial cancer among breast cancer survivors aged 55–79 years was still observed, although not significantly (HR: 0.74, 95%CI: 0.46–1.17). Conclusions Dang-qui consumption is common among breast cancer survivors aged 20–79 years and seems decrease the risk of subsequent endometrial cancer after less than a cumulative dose of 7,500 mg of tamoxifen treatment. PMID:25485843

Relation of Post-Coronary Artery Bypass Graft Creatine Kinase-MB Elevations and New Q Waves With Long-Term Cardiovascular Death in Patients With Diabetes Mellitus and Multivessel Coronary Artery Disease.

PubMed

Domanski, Michael; Farkouh, Michael E; Zak, Victor; French, John; Alexander, John H; Bochenek, Andrzej; Hamon, Martial; Mahaffey, Kenneth; Puskas, John; Smith, Peter; Shrader, Peter; Fuster, Valentin

2016-12-01

Associations of early creatine phosphokinase-MB (CK-MB) elevation and new Q waves and their association with cardiovascular death (CVD) after coronary artery bypass grafting (CABG) have been reported, but this association has not been studied in a large population of patients with diabetes mellitus. In this study, we examine the association of periprocedural CK-MB elevations and new Q waves with CVD in the Future Revascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multivessel Disease trial. Cox proportional hazards regression was used to assess the relation of CK-MB elevations and new Q waves in the first 24 hours after procedure and their relation to CVD; logistic regression was used to assess odds ratios of these variables. Hazard ratios, 95% confidence intervals, and p values associated with Wald chi-square test are reported. CK-MB elevation in first 24 hours after procedure was independently associated with CVD. CVD hazard increased by 6% (p <0.001) with each multiple of CK-MB above the upper reference limit (URL); odds of new post-CABG Q waves increased by a factor of 1.08 (p <0.001); at 7× CK-MB URL, HR was >2. CK-MB URL multiples of 7, 12, and 15 were associated with new Q-wave odds ratios of 9, 16, and 27 times, respectively (p ≤0.001, C-statistic >0.70). New Q waves were independently associated with survival in the multivariate model only when CK-MB was excluded (p = 0.01). In conclusion, independent associations included (1) CVD and early post-CABG CK-MB elevation; (2) new Q waves with early post-CABG CK-MB elevation; (3) CVD with new Q waves only when CK-MB elevation is excluded from analysis. Copyright © 2016 Elsevier Inc. All rights reserved.

Primary gastric mucosa associated lymphoid tissue lymphoma: Clinical data predicted treatment outcome

PubMed Central

Todorovic, Milena; Balint, Bela; Jevtic, Miodrag; Suvajdzic, Nada; Ceric, Amela; Stamatovic, Dragana; Markovic, Olivera; Perunicic, Maja; Marjanovic, Slobodan; Krstic, Miodrag

2008-01-01

AIM: To determine clinical characteristics and treatment outcome of gastric lymphoma after chemotherapy and immuno-chemotherapy. METHODS: Thirty four patients with primary gastric mucosa associated lymphoid tissue (MALT) lymphoma (Ann Arbor stages I to IV) were enrolled. All had upper gastric endoscopy, abdominal ultrasonography, CT and H pylori status assessment (histology and serology). After anti-H pylori treatment and initial chemotherapy, patients were re-examined every 4 mo. RESULTS: Histological regression of the lymphoma was complete in 22/34 (64.7%) and partial in 9 (26.5%) patients. Median follow up time for these 31 responders was 60 mo (range 48-120). No regression was noted in 3 patients. Among the 25 (73.5%) H pylori positive patients, the eradication rate was 100%. CONCLUSION: Using univariate analysis, predictive factors for overall survival were international prognostic index (IPI) score, hemoglobin level, erythrocyte sedimentation rate (ESR), and platelet numbers (P < 0.005). In addition to this, Cox proportion hazard model differentiate IPI score, ESR, and platelets as predictors of survival. PMID:18416467

A global goodness-of-fit statistic for Cox regression models.

PubMed

Parzen, M; Lipsitz, S R

1999-06-01

In this paper, a global goodness-of-fit test statistic for a Cox regression model, which has an approximate chi-squared distribution when the model has been correctly specified, is proposed. Our goodness-of-fit statistic is global and has power to detect if interactions or higher order powers of covariates in the model are needed. The proposed statistic is similar to the Hosmer and Lemeshow (1980, Communications in Statistics A10, 1043-1069) goodness-of-fit statistic for binary data as well as Schoenfeld's (1980, Biometrika 67, 145-153) statistic for the Cox model. The methods are illustrated using data from a Mayo Clinic trial in primary billiary cirrhosis of the liver (Fleming and Harrington, 1991, Counting Processes and Survival Analysis), in which the outcome is the time until liver transplantation or death. The are 17 possible covariates. Two Cox proportional hazards models are fit to the data, and the proposed goodness-of-fit statistic is applied to the fitted models.

Sparse kernel methods for high-dimensional survival data.

PubMed

Evers, Ludger; Messow, Claudia-Martina

2008-07-15

Sparse kernel methods like support vector machines (SVM) have been applied with great success to classification and (standard) regression settings. Existing support vector classification and regression techniques however are not suitable for partly censored survival data, which are typically analysed using Cox's proportional hazards model. As the partial likelihood of the proportional hazards model only depends on the covariates through inner products, it can be 'kernelized'. The kernelized proportional hazards model however yields a solution that is dense, i.e. the solution depends on all observations. One of the key features of an SVM is that it yields a sparse solution, depending only on a small fraction of the training data. We propose two methods. One is based on a geometric idea, where-akin to support vector classification-the margin between the failed observation and the observations currently at risk is maximised. The other approach is based on obtaining a sparse model by adding observations one after another akin to the Import Vector Machine (IVM). Data examples studied suggest that both methods can outperform competing approaches. Software is available under the GNU Public License as an R package and can be obtained from the first author's website http://www.maths.bris.ac.uk/~maxle/software.html.

Diabetes mellitus with obesity is a predictor of recurrence in patients with non-metastatic renal cell carcinoma.

PubMed

Fukushima, Hiroshi; Masuda, Hitoshi; Yokoyama, Minato; Tatokoro, Manabu; Yoshida, Soichiro; Ishioka, Junichiro; Matsuoka, Yoh; Numao, Noboru; Koga, Fumitaka; Saito, Kazutaka; Fujii, Yasuhisa; Kihara, Kazunori

2013-07-01

To investigate the associations of diabetes mellitus with recurrence and prognosis after surgery for non-metastatic renal cell carcinoma and the effect modification of obesity on the above relationships. We retrospectively evaluated 543 patients with non-metastatic renal cell carcinoma (pT1-4N0M0) who underwent radical or partial nephrectomy. The association of diabetes mellitus with recurrence was analyzed using the Kaplan-Meier method and the Cox regression model. We also examined whether the above relationships were modified by obesity using subgroup analysis and tests of interaction. For subgroup analysis, the body mass index was categorized as non-obese (<25 kg/m(2)) and obese (≥25 kg/m(2)). Eighty-two patients (15.1%) had a history of diabetes mellitus. During the mean follow-up of 66.7 months, 68 patients (12.5%) developed recurrence. Although the body mass index was not associated with recurrence, diabetes mellitus was an independent predictor of recurrence in multivariate analysis (hazard ratio 2.43, P = 0.003), along with tumor diameter, grade and pathological T stage. In further subgroup analysis, the same relationship between diabetes mellitus and recurrence was clearly shown in the obese group (hazard ratio 4.07, P = 0.010), but not in the non-obese group (hazard ratio 1.95, P = 0.125). At the same time, obesity modified the effect of diabetes mellitus on recurrence with a trend (P-interaction = 0.086). In the obese group, 5-year recurrence-free survival rates were 75.3 and 91.9% for diabetes mellitus and non-diabetes mellitus patients, respectively (P < 0.001). Restricting analyses to patients with clear cell type histology did not materially change these results. Diabetes mellitus is a predictor of recurrence following surgery for non-metastatic renal cell carcinoma, especially in obese patients.

The prevalence of smoking, second-hand smoke exposure, and knowledge of the health hazards of smoking among internal migrants in 12 provinces in China: a cross-sectional analysis.

PubMed

Zheng, Yunting; Ji, Ying; Dong, Hongbo; Chang, Chun

2018-05-24

Previous studies have provided inconsistent findings on smoking among migrants, and very limited data exist on their second-hand smoke exposure. This study aims to investigate internal migrants' smoking prevalence, second-hand smoke exposure among non-smokers, and knowledge of the health hazards of smoking in 12 major migrant provinces in China in 2013. Data from the 2013 Migrant Dynamics Monitoring Survey in China published by the National Commission of Health and Family Planning was used in this study. Descriptive analysis, Chi-square analysis, and sex-stratified multivariate logistic regression analysis were used to explore the determinants of current smoking and second-hand smoke exposure. Among 7200 migrants, 34.1% (55% male, 4% female) were current smokers. For males, factors associated with current smoking were education year (aOR = 0.95, 95% CI: 0.93-0.98), duration of stay (aOR = 1.01, 95% CI: 1.00-1.03) and occupation (aOR = 1.25, 95% CI: 1.03-1.53). For females, household registration status (aOR = 1.70, 95% CI: 1.04-2.80) was the most important factor associated with current smoking. Sixty five percent of non-smokers were exposed to second-hand smoke. Factors associated with exposure to second-hand smoke were duration of stay (aOR = 1.01, 95% CI: 1.00-1.02), divorced/widowed marital status (aOR = 0.48, 95% CI: 0.25-0.91), occupation (aOR = 1.29, 95% CI: 1.05-1.58) and the nature of employer (aOR = 0.77, 95% CI: 0.60-0.97). About 95% of participants were aware that lung cancer is one of the hazards of smoking. Non-current smokers had a better knowledge of fertility reduction and accelerated aging as hazards of smoking than current smokers (p < 0.01). Knowledge of the impact of smoking on cardiovascular diseases was relatively low compared with knowledge of other smoking-related hazards (26.1-44.3%). Current smoking and exposure to second-hand smoke among internal migrants in China is high. Socio-demographic characteristics and migration status were strongly associated with current smoking and second-hand smoke exposure. We recommend specifically targeted tobacco control interventions to help to address these risk factors, such as focusing on divorced/widowed women.

Hazardous drinking and exposure to interpersonal and community violence on both sides of the U.S. -Mexico border.

PubMed

Lown, E A; Cherpitel, C J; Zemore, S E; Borges, G; Greenfield, T K

2017-11-01

Different patterns of heavy drinking occur by country and proximity to the U.S. Mexico border. Few studies describe the impact of violence on drinking between countries and along the border. Survey data is from U.S. Mexican origin adults living in Texas and Mexican border and non-border cities, N=4,796. Participants were asked about alcohol consumption, interpersonal physical violence (IPV) and exposure to community violence. Monthly hazardous drinking (5+/4+ for men/women) was the primary outcome. Multivariate logistic regression model comparisons identified best predictors. In the U.S. hazardous drinking was associated with past year IPV (OR adj =2.5; 1.8-3.5) and community violence (OR adj =1.4; 1.1-1.8). In Mexico, IPV (OR adj =3.9; 2.0-7.4) and border proximity (OR adj =0.5; 0.4-0.8) were associated with hazardous drinking but not community violence. Hazardous drinking is associated with IPV in both countries, but violence did not explain border hazardous drinking differences where they existed in Mexico.

Renal Cell Carcinoma: Comparison of RENAL Nephrometry and PADUA Scores with Maximum Tumor Diameter for Prediction of Local Recurrence after Thermal Ablation.

PubMed

Maxwell, Aaron W P; Baird, Grayson L; Iannuccilli, Jason D; Mayo-Smith, William W; Dupuy, Damian E

2017-05-01

Purpose To evaluate the performance of the radius, exophytic or endophytic, nearness to collecting system or sinus, anterior or posterior, and location relative to polar lines (RENAL) nephrometry and preoperative aspects and dimensions used for anatomic classification (PADUA) scoring systems and other tumor biometrics for prediction of local tumor recurrence in patients with renal cell carcinoma after thermal ablation. Materials and Methods This HIPAA-compliant study was performed with a waiver of informed consent after institutional review board approval was obtained. A retrospective evaluation of 207 consecutive patients (131 men, 76 women; mean age, 71.9 years ± 10.9) with 217 biopsy-proven renal cell carcinoma tumors treated with thermal ablation was conducted. Serial postablation computed tomography (CT) or magnetic resonance (MR) imaging was used to evaluate for local tumor recurrence. For each tumor, RENAL nephrometry and PADUA scores were calculated by using imaging-derived tumor morphologic data. Several additional tumor biometrics and combinations thereof were also measured, including maximum tumor diameter. The Harrell C index and hazard regression techniques were used to quantify associations with local tumor recurrence. Results The RENAL (hazard ratio, 1.43; P = .003) and PADUA (hazard ratio, 1.80; P < .0001) scores were found to be significantly associated with recurrence when regression techniques were used but demonstrated only poor to fair discrimination according to Harrell C index results (C, 0.68 and 0.75, respectively). Maximum tumor diameter showed the highest discriminatory strength of any individual variable evaluated (C, 0.81) and was also significantly predictive when regression techniques were used (hazard ratio, 2.98; P < .0001). For every 1-cm increase in diameter, the estimated rate of recurrence risk increased by 198%. Conclusion Maximum tumor diameter demonstrates superior performance relative to existing tumor scoring systems and other evaluated biometrics for prediction of local tumor recurrence after renal cell carcinoma ablation. © RSNA, 2016.

77 FR 55371 - System Safety Program

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-07

...-based rule and FRA seeks comments on all aspects of the proposed rule. An SSP would be implemented by a... SSP would be the risk-based hazard management program and risk-based hazard analysis. A properly implemented risk-based hazard management program and risk-based hazard analysis would identify the hazards and...

Sodium Intake and Osteoporosis. Findings From the Women's Health Initiative.

PubMed

Carbone, Laura; Johnson, Karen C; Huang, Ying; Pettinger, Mary; Thomas, Fridjtof; Cauley, Jane; Crandall, Carolyn; Tinker, Lesley; LeBoff, Meryl Susan; Wactawski-Wende, Jean; Bethel, Monique; Li, Wenjun; Prentice, Ross

2016-04-01

In this large, prospective, observational cohort study of postmenopausal women in the WHI, Cox proportional hazard regression models showed that sodium intake at or near recommended levels is not likely to impact bone metabolism.

Probabilistic Seismic Hazard Assessment for Northeast India Region

NASA Astrophysics Data System (ADS)

Das, Ranjit; Sharma, M. L.; Wason, H. R.

2016-08-01

Northeast India bounded by latitudes 20°-30°N and longitudes 87°-98°E is one of the most seismically active areas in the world. This region has experienced several moderate-to-large-sized earthquakes, including the 12 June, 1897 Shillong earthquake ( M w 8.1) and the 15 August, 1950 Assam earthquake ( M w 8.7) which caused loss of human lives and significant damages to buildings highlighting the importance of seismic hazard assessment for the region. Probabilistic seismic hazard assessment of the region has been carried out using a unified moment magnitude catalog prepared by an improved General Orthogonal Regression methodology (Geophys J Int, 190:1091-1096, 2012; Probabilistic seismic hazard assessment of Northeast India region, Ph.D. Thesis, Department of Earthquake Engineering, IIT Roorkee, Roorkee, 2013) with events compiled from various databases (ISC, NEIC,GCMT, IMD) and other available catalogs. The study area has been subdivided into nine seismogenic source zones to account for local variation in tectonics and seismicity characteristics. The seismicity parameters are estimated for each of these source zones, which are input variables into seismic hazard estimation of a region. The seismic hazard analysis of the study region has been performed by dividing the area into grids of size 0.1° × 0.1°. Peak ground acceleration (PGA) and spectral acceleration ( S a) values (for periods of 0.2 and 1 s) have been evaluated at bedrock level corresponding to probability of exceedance (PE) of 50, 20, 10, 2 and 0.5 % in 50 years. These exceedance values correspond to return periods of 100, 225, 475, 2475, and 10,000 years, respectively. The seismic hazard maps have been prepared at the bedrock level, and it is observed that the seismic hazard estimates show a significant local variation in contrast to the uniform hazard value suggested by the Indian standard seismic code [Indian standard, criteria for earthquake-resistant design of structures, fifth edition, Part-I. Bureau of Indian Standards, New Delhi, 2002]. Not only holistic treatment of earthquake catalog and seismogenic zones has been performed, but also higher resolution in spatial distribution could be achieved. The COV maps have been provided with the strong ground-motion maps under various conditions to show the confidence in the results obtained. Results obtained in the present study would be helpful for risk assessment and other disaster mitigation-related studies.

Mental Health Symptoms Among Student Service Members/Veterans and Civilian College Students.

PubMed

Cleveland, Sandi D; Branscum, Adam J; Bovbjerg, Viktor E; Thorburn, Sheryl

2015-01-01

The aim of this study was to investigate if and to what extent student service members/veterans differ from civilian college students in the prevalence of self-reported symptoms of poor mental health. The Fall 2011 implementation of the American College Health Association-National College Health Assessment included 27,774 respondents from 44 colleges and universities. Participants were matched using propensity scores, and the prevalence of symptoms was compared using logistic regression and zero-inflated negative binomial regression models. The odds of feeling overwhelmed in the last 12 months were significantly lower among student service members/veterans with a history of hazardous duty (odd ratio [OR] = 0.46, adjusted p value <.05) compared with civilian students. Military service, with and without hazardous duty deployment, was not a significant predictor of the total number of symptoms of poor mental health. Current student service members/veterans may not be disproportionately affected by poor psychological functioning.

High-Throughput Models for Exposure-Based Chemical ...

EPA Pesticide Factsheets

The United States Environmental Protection Agency (U.S. EPA) must characterize potential risks to human health and the environment associated with manufacture and use of thousands of chemicals. High-throughput screening (HTS) for biological activity allows the ToxCast research program to prioritize chemical inventories for potential hazard. Similar capabilities for estimating exposure potential would support rapid risk-based prioritization for chemicals with limited information; here, we propose a framework for high-throughput exposure assessment. To demonstrate application, an analysis was conducted that predicts human exposure potential for chemicals and estimates uncertainty in these predictions by comparison to biomonitoring data. We evaluated 1936 chemicals using far-field mass balance human exposure models (USEtox and RAIDAR) and an indicator for indoor and/or consumer use. These predictions were compared to exposures inferred by Bayesian analysis from urine concentrations for 82 chemicals reported in the National Health and Nutrition Examination Survey (NHANES). Joint regression on all factors provided a calibrated consensus prediction, the variance of which serves as an empirical determination of uncertainty for prioritization on absolute exposure potential. Information on use was found to be most predictive; generally, chemicals above the limit of detection in NHANES had consumer/indoor use. Coupled with hazard HTS, exposure HTS can place risk earlie

Biologic and social determinants of sequelae and long-term survival of pediatric HIV in Romania.

PubMed

Kozinetz, Claudia A; Matusa, Rodica; Hacker, Carl S

2006-08-01

The aim of the study is to investigate the effect of social context and clinical factors on survival in a cohort of 333 children to identify issues useful in the treatment and care of human immunodeficiency virus (HIV)-infected youth in developing countries. A prospective cohort study design was used, and data were gathered at baseline and 1-year follow-up. The study cohort consisted of children given a diagnosis of HIV between 1995 and 1999 and receiving medical care in Constanta, Romania. Data were examined by means of multivariate Cox regression analysis models. The majority of the cohort were in the moderate (41%) or severe (40%) stages of HIV at baseline. Multivariate analysis indicated that social-context factors were the most significant determinants of HIV survival. The hazard for death for those with mothers or fathers with a higher level of education was approximately one quarter (relative hazard, 0.3-0.4; confidence interval, 0.1-1.0) that for a parent with a lower level of education. Subjects with employed mothers were four times more likely to survive than subjects with unemployed mothers. Results suggest that recognition of social-context risk factors for HIV disease progression and survival is important in developing countries, as it is in developed countries.

Lactate clearance cut off for early mortality prediction in adult sepsis and septic shock patients

NASA Astrophysics Data System (ADS)

Sinto, R.; Widodo, D.; Pohan, H. T.

2018-03-01

Previous lactate clearance cut off for early mortality prediction in sepsis and septic shock patient was determined by consensus from small sample size-study. We investigated the best lactate clearance cut off and its ability to predict early mortality in sepsis and septic shock patients. This cohort study was conducted in Intensive Care Unit of CiptoMangunkusumo Hospital in 2013. Patients’ lactate clearance and eight other resuscitationendpoints were recorded, and theoutcome was observed during the first 120 hours. The clearance cut off was determined using receiver operating characteristic (ROC) analysis, and its ability was investigated with Cox’s proportional hazard regression analysis using other resuscitation endpoints as confounders. Total of 268 subjects was included, of whom 70 (26.11%) subjects died within the first 120 hours. The area under ROC of lactate clearance to predict early mortality was 0.78 (95% % confidence interval [CI] 0.71-0.84) with best cut off was <7.5% (sensitivity and specificity 88.99% and 81.4% respectively). Compared with group achieving lactate clearance target, group not achieving lactate clearance target had to increase early mortality risk (adjusted hazard ratio 13.42; 95%CI 7.19-25.07). In conclusion, the best lactate clearance cut off as anearly mortality predictor in sepsis and septic shock patients is 7.5%.

Leukocytosis is a risk factor for recurrent arterial thrombosis in young patients with polycythemia vera and essential thrombocythemia.

PubMed

De Stefano, Valerio; Za, Tommaso; Rossi, Elena; Vannucchi, Alessandro M; Ruggeri, Marco; Elli, Elena; Micò, Caterina; Tieghi, Alessia; Cacciola, Rossella R; Santoro, Cristina; Gerli, Giancarla; Guglielmelli, Paola; Pieri, Lisa; Scognamiglio, Francesca; Rodeghiero, Francesco; Pogliani, Enrico M; Finazzi, Guido; Gugliotta, Luigi; Leone, Giuseppe; Barbui, Tiziano

2010-02-01

There is evidence that leukocytosis is associated with an increased risk of first thrombosis in patients with polycythemia vera (PV) and essential thrombocythemia (ET). Whether it is a risk factor for recurrent thrombosis too is currently unknown. In the frame of a multicenter retrospective cohort study, we recruited 253 patients with PV (n = 133) or ET (n = 120), who were selected on the basis of a first arterial (70%) or venous major thrombosis (27.6%) or both (2.4%), and who were not receiving cytoreduction at the time of thrombosis. The probability of recurrent thrombosis associated with the leukocyte count recorded at the time of the first thrombosis was estimated by a receiver operating characteristic analysis and a multivariable Cox proportional hazards regression model. Thrombosis recurred in 78 patients (30.7%); multivariable analysis showed an independent risk of arterial recurrence (hazard ratio [HR] 2.16, 95% CI 1.12-4.18) in patients with a leukocyte count that was >12.4 x 10(9)/L at the time of the first thrombotic episode. The prognostic role for leukocytosis was age-related, as it was only significant in patients that were aged <60 years (HR for arterial recurrence 3.35, 95% CI 1.22-9.19).

Novel nitric oxide producing probiotic wound healing patch: preparation and in vivo analysis in a New Zealand white rabbit model of ischaemic and infected wounds.

PubMed

Jones, Mitchell; Ganopolsky, Jorge G; Labbé, Alain; Gilardino, Mirko; Wahl, Christopher; Martoni, Christopher; Prakash, Satya

2012-06-01

The treatment of chronic wounds poses a significant challenge for clinicians and patients alike. Here we report design and preclinical efficacy of a novel nitric oxide gas (gNO)-producing probiotic patch for wound healing. Specifically, a wound healing patch using lactic acid bacteria in an adhesive gas permeable membrane has been designed and investigated for treating ischaemic and infected full-thickness dermal wounds in a New Zealand white rabbit model for ischaemic wound healing. Kaplan-Meier survival curves showed increased wound closure with gNO-producing patch-treated wounds over 21 days of therapy (log-rank P = 0·0225 and Wilcoxon P = 0·0113). Cox proportional hazard regression showed that gNO-producing patch-treated wounds were 2·52 times more likely to close compared with control patches (hazard P = 0·0375, score P = 0·032 and likelihood ratio P = 0·0355), and histological analysis showed improved wound healing in gNO-producing patch-treated animals. This study may provide an effective, safe and less costly alternative for treating chronic wounds. © 2012 The Authors. © 2012 Blackwell Publishing Ltd and Medicalhelplines.com Inc.

Nonparametric change point estimation for survival distributions with a partially constant hazard rate.

PubMed

Brazzale, Alessandra R; Küchenhoff, Helmut; Krügel, Stefanie; Schiergens, Tobias S; Trentzsch, Heiko; Hartl, Wolfgang

2018-04-05

We present a new method for estimating a change point in the hazard function of a survival distribution assuming a constant hazard rate after the change point and a decreasing hazard rate before the change point. Our method is based on fitting a stump regression to p values for testing hazard rates in small time intervals. We present three real data examples describing survival patterns of severely ill patients, whose excess mortality rates are known to persist far beyond hospital discharge. For designing survival studies in these patients and for the definition of hospital performance metrics (e.g. mortality), it is essential to define adequate and objective end points. The reliable estimation of a change point will help researchers to identify such end points. By precisely knowing this change point, clinicians can distinguish between the acute phase with high hazard (time elapsed after admission and before the change point was reached), and the chronic phase (time elapsed after the change point) in which hazard is fairly constant. We show in an extensive simulation study that maximum likelihood estimation is not robust in this setting, and we evaluate our new estimation strategy including bootstrap confidence intervals and finite sample bias correction.

Trust, confidence, procedural fairness, outcome fairness, moral conviction, and the acceptance of GM field experiments.

PubMed

Siegrist, Michael; Connor, Melanie; Keller, Carmen

2012-08-01

In 2005, Swiss citizens endorsed a moratorium on gene technology, resulting in the prohibition of the commercial cultivation of genetically modified crops and the growth of genetically modified animals until 2013. However, scientific research was not affected by this moratorium, and in 2008, GMO field experiments were conducted that allowed us to examine the factors that influence their acceptance by the public. In this study, trust and confidence items were analyzed using principal component analysis. The analysis revealed the following three factors: "economy/health and environment" (value similarity based trust), "trust and honesty of industry and scientists" (value similarity based trust), and "competence" (confidence). The results of a regression analysis showed that all the three factors significantly influenced the acceptance of GM field experiments. Furthermore, risk communication scholars have suggested that fairness also plays an important role in the acceptance of environmental hazards. We, therefore, included measures for outcome fairness and procedural fairness in our model. However, the impact of fairness may be moderated by moral conviction. That is, fairness may be significant for people for whom GMO is not an important issue, but not for people for whom GMO is an important issue. The regression analysis showed that, in addition to the trust and confidence factors, moral conviction, outcome fairness, and procedural fairness were significant predictors. The results suggest that the influence of procedural fairness is even stronger for persons having high moral convictions compared with persons having low moral convictions. © 2012 Society for Risk Analysis.

Pressure ulcer incidence and Braden subscales: Retrospective cohort analysis in general wards of a Portuguese hospital.

PubMed

Sardo, Pedro Miguel Garcez; Guedes, Jenifer Adriana Domingues; Alvarelhão, José Joaquim Marques; Machado, Paulo Alexandre Puga; Melo, Elsa Maria Oliveira Pinheiro

2018-05-01

To study the influence of Braden subscales scores (at the first pressure ulcer risk assessment) on pressure ulcer incidence using a univariate and a multivariate time to event analysis. Retrospective cohort analysis of electronic health record database from adult patients admitted without pressure ulcer(s) to medical and surgical wards of a Portuguese hospital during 2012. The hazard ratio of developing a pressure ulcer during the length of inpatient stay was calculated by univariate Cox regression for each variable of interest and by multivariate Cox regression for the Braden subscales that were statistically significant. This study included a sample of 6552 participants. During the length of stay, 153 participants developed (at least) one pressure ulcer, giving a pressure ulcer incidence of 2.3%. The univariate time to event analysis showed that all Braden subscales, except "nutrition", were associated with the development of pressure ulcer. By multivariate analysis the scores for "mobility" and "activity" were independently predictive of the development of pressure ulcer(s) for all participants. (Im)"mobility" (the lack of ability to change and control body position) and (in)"activity" (the limited degree of physical activity) were the major risk factors assessed by Braden Scale for pressure ulcer development during the length of inpatient stay. Thus, the greatest efforts in managing pressure ulcer risk should be on "mobility" and "activity", independently of the total Braden Scale score. Copyright © 2018 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.

Modelling the changing cumulative vulnerability to climate-related hazards for river basin management using a GIS-based multicriteria decision approach

NASA Astrophysics Data System (ADS)

Hung, Hung-Chih; Wu, Ju-Yu; Hung, Chih-Hsuan

2017-04-01

1. Background Asia-Pacific region is one of the most vulnerable areas of the world to climate-related hazards and extremes due to rapid urbanization and over-development in hazard-prone areas. It is thus increasingly recognized that the management of land use and reduction of hazard risk are inextricably linked. This is especially critical from the perspective of integrated river basin management. A range of studies has targeted existing vulnerability assessments. However, limited attention has been paid to the cumulative effects of multiple vulnerable factors and their dynamics faced by local communities. This study proposes a novel methodology to access the changing cumulative vulnerability to climate-related hazards, and to examine the relationship between the attraction factors relevant to the general process of urbanization and vulnerability variability with a focus on a river basin management unit. 2. Methods and data The methods applied in this study include three steps. First, using Intergovernmental Panel on Climate Change's (IPCC) approach, a Cumulative Vulnerability Assessment Framework (CVAF) is built with a goal to characterize and compare the vulnerability to climate-related hazards within river basin regions based on a composition of multiple indicators. We organize these indicator metrics into three categories: (1) hazard exposure; (2) socioeconomic sensitivity, and (3) adaptive capacity. Second, the CVAF is applied by combining a geographical information system (GIS)-based spatial statistics technique with a multicriteria decision analysis (MCDA) to assess and map the changing cumulative vulnerability, comparing conditions in 1996 and 2006 in Danshui River Basin, Taiwan. Third, to examine the affecting factors of vulnerability changing, we develop a Vulnerability Changing Model (VCM) using four attraction factors to reflect how the process of urban developments leads to vulnerability changing. The factors are transport networks, land uses, production values of industries, and infrastructures. We then conduct a regression analysis to test the VCM. To illustrate the proposed methodology, the data are collected from the National Science and Technology Center for Disaster Reduction, Taiwan as well as the National Land Use Investigation and official census statistics. 3. Results and policy implications Results of CVAF analysis demonstrate heterogeneous patterns of vulnerability in the region, and highlight trends of long-term changes. The vulnerable areas unfold as clustered patterns and spatial analogues across regions, rather than randomly distributed. Highest cumulative vulnerability is concentrated in densely populated and downstream reaches (such as Taipei City) of the Danshui River in both time periods. When examining the VCM, it indicates that upper stream and more remote areas generally show low vulnerability, increases are observed in some areas between 1996 and 2006 due to land use intensification, industrial and infrastructure expansion. These findings suggest that land use planning should consider the socioeconomic progression and infrastructure investment factors that contribute to urban sprawl and address current as well as future urban developments vulnerable to hazard risk transmission. The cumulative vulnerability assessment, mapping methods and modelling presented here can be applied to other climate change and hazard risks to highlight priority areas for further investigation and contribute towards improving river basin management.

9 CFR 417.2 - Hazard Analysis and HACCP Plan.

Code of Federal Regulations, 2012 CFR

2012-01-01

... more food safety hazards that are reasonably likely to occur, based on the hazard analysis conducted in... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Hazard Analysis and HACCP Plan. 417.2 Section 417.2 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE...

9 CFR 417.2 - Hazard Analysis and HACCP Plan.

Code of Federal Regulations, 2014 CFR

2014-01-01

... more food safety hazards that are reasonably likely to occur, based on the hazard analysis conducted in... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Hazard Analysis and HACCP Plan. 417.2 Section 417.2 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE...

9 CFR 417.2 - Hazard Analysis and HACCP Plan.

Code of Federal Regulations, 2011 CFR

2011-01-01

... more food safety hazards that are reasonably likely to occur, based on the hazard analysis conducted in... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Hazard Analysis and HACCP Plan. 417.2 Section 417.2 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE...

9 CFR 417.2 - Hazard Analysis and HACCP Plan.

Code of Federal Regulations, 2013 CFR

2013-01-01

... more food safety hazards that are reasonably likely to occur, based on the hazard analysis conducted in... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Hazard Analysis and HACCP Plan. 417.2 Section 417.2 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE...

9 CFR 417.2 - Hazard Analysis and HACCP Plan.

Code of Federal Regulations, 2010 CFR

2010-01-01

... more food safety hazards that are reasonably likely to occur, based on the hazard analysis conducted in... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Hazard Analysis and HACCP Plan. 417.2 Section 417.2 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE...

Hazardous Drinking and HIV-risk-related Behaviour among Male Clients of Female Sex Workers in Tijuana, Mexico

PubMed Central

Goodman-Meza, David; Pitpitan, Eileen V.; Semple, Shirley J.; Wagner, Karla D.; Chavarin, Claudia V.; Strathdee, Steffanie A.; Patterson, Thomas L.

2015-01-01

Background and Objectives Male clients of female sex workers (FSWs) are at high risk for HIV. Whereas the HIV risks of alcohol use are well understood, less is known about hazardous alcohol use among male clients of FSWs, particularly in Mexico. We sought to identify risk factors for hazardous alcohol use and test associations between hazardous alcohol use and HIV risk behaviour among male clients in Tijuana. Method Male clients of FSWs in Tijuana (n = 400) completed a quantitative interview in 2008. The AUDIT was used to characterize hazardous alcohol use. Multivariate logistic regression was used to determine independent associations of demographic and HIV risk variables with hazardous alcohol use (vs. non-hazardous). Results Forty percent of our sample met criteria for hazardous alcohol use. Variables independently associated with hazardous drinking were reporting any sexually transmitted infection (STI), having sex with a FSW while under the influence of alcohol, being younger than 36 years of age, living in Tijuana, and ever having been jailed. Hazardous drinkers were less likely ever to have been deported or to have shared injection drugs. Discussion and Conclusions Hazardous alcohol use is associated with HIV risk, including engaging in sex with FSWs while intoxicated and having an STI among male clients of FSWs in Tijuana. Scientific Significance We systematically described patterns and correlates of hazardous alcohol use among male clients of FSWs in Tijuana, Mexico. The results suggest that HIV/STI risk reduction interventions must target hazardous alcohol users, and be tailored to address alcohol use. PMID:25066863

Hazardous drinking and HIV-risk-related behavior among male clients of female sex workers in Tijuana, Mexico.

PubMed

Goodman-Meza, David; Pitpitan, Eileen V; Semple, Shirley J; Wagner, Karla D; Chavarin, Claudia V; Strathdee, Steffanie A; Patterson, Thomas L

2014-01-01

Male clients of female sex workers (FSWs) are at high risk for HIV. Whereas the HIV risks of alcohol use are well understood, less is known about hazardous alcohol use among male clients of FSWs, particularly in Mexico. We sought to identify risk factors for hazardous alcohol use and test associations between hazardous alcohol use and HIV risk behavior among male clients in Tijuana. Male clients of FSWs in Tijuana (n = 400) completed a quantitative interview in 2008. The AUDIT was used to characterize hazardous alcohol use. Multivariate logistic regression was used to determine independent associations of demographic and HIV risk variables with hazardous alcohol use (vs. non-hazardous). Forty percent of our sample met criteria for hazardous alcohol use. Variables independently associated with hazardous drinking were reporting any sexually transmitted infection (STI), having sex with a FSW while under the influence of alcohol, being younger than 36 years of age, living in Tijuana, and ever having been jailed. Hazardous drinkers were less likely ever to have been deported or to have shared injection drugs. Hazardous alcohol use is associated with HIV risk, including engaging in sex with FSWs while intoxicated and having an STI among male clients of FSWs in Tijuana. We systematically described patterns and correlates of hazardous alcohol use among male clients of FSWs in Tijuana, Mexico. The results suggest that HIV/STI risk reduction interventions must target hazardous alcohol users, and be tailored to address alcohol use. © American Academy of Addiction Psychiatry.

Individual and community level risk-factors for alcohol use disorder among conflict-affected persons in Georgia.

PubMed

Roberts, Bayard; Murphy, Adrianna; Chikovani, Ivdity; Makhashvili, Nino; Patel, Vikram; McKee, Martin

2014-01-01

The evidence on alcohol use disorder among conflict-affected civilian populations remains extremely weak, despite a number of potential risk-factors. The aim of this study is to examine patterns of alcohol use disorder among conflict-affected persons in the Republic of Georgia. A cross-sectional survey of 3600 randomly selected internally displaced persons (IDPs) and former IDPs. Two alcohol use disorder outcomes were measured: (i) having at least hazardous alcohol use (AUDIT score ≥ 8); (ii) episodic heavy drinking (consuming >60 grams of pure alcohol per drinking session at least once a week). Individual level demographic and socio-economic characteristics were also recorded, including mental disorders. Community level alcohol environment characteristics relating to alcohol availability, marketing and pricing were recorded in the respondents' communities and a factor analysis conducted to produce a summary alcohol environment factor score. Logistic regression analyses examined associations between individual and community level factors with the alcohol use disorder outcomes (among men only). Of the total sample, 71% of men and 16% of women were current drinkers. Of the current drinkers (N = 1386), 28% of men and 1% of women were classified as having at least hazardous alcohol use; and 12% of men and 2% of women as episodic heavy drinkers. Individual characteristics significantly associated with both outcomes were age and experiencing a serious injury, while cumulative trauma events and depression were also associated with having at least hazardous alcohol use. For the community level analysis, a one unit increase in the alcohol environment factor was associated with a 1.27 fold increase in episodic heavy drinking among men (no significant association with hazardous alcohol use). The findings suggest potential synergies for treatment responses for alcohol use disorder and depression among conflict-affected populations in Georgia, as well as the need for stronger alcohol control policies in Georgia.

Serum Uric Acid and Renal Transplantation Outcomes: At Least 3-Year Post-transplant Retrospective Multivariate Analysis

PubMed Central

Zhang, Kun; Gao, Baoshan; Wang, Yuantao; Wang, Gang; Wang, Weigang; Zhu, Yaxiang; Yao, Liyu; Gu, Yiming; Chen, Mo; Zhou, Honglan; Fu, Yaowen

2015-01-01

Since the association of serum uric acid and kidney transplant graft outcome remains disputable, we sought to evaluate the predictive value of uric acid level for graft survival/function and the factors could affect uric acid as time varies. A consecutive cohort of five hundred and seventy three recipients transplanted during January 2008 to December 2011 were recruited. Data and laboratory values of our interest were collected at 1, 3, 6, 12, 24 and 36 months post-transplant for analysis. Cox proportional hazard model, and multiple regression equation were built to adjust for the possible confounding variables and meet our goals as appropriate. The current cohort study lasts for 41.86 ± 15.49 months. Uric acid level is proven to be negatively associated with eGFR at different time point after adjustment for age, body mass index and male gender (standardized β ranges from -0.15 to -0.30 with all P<0.001).Males with low eGFR but high level of TG were on CSA, diuretics and RAS inhibitors and experienced at least one episode of acute rejection and diabetic issue were associated with a higher mean uric acid level. Hyperuricemia was significantly an independent predictor of pure graft failure (hazard ratio=4.01, 95% CI: 1.25-12.91, P=0.02) after adjustment. But it was no longer an independent risk factor for graft loss after adjustment. Interestingly, higher triglyceride level can make incidence of graft loss (hazard ratio=1.442, for each unit increase millimoles per liter 95% CI: 1.008-2.061, P=0.045) and death (hazard ratio=1.717, 95% CI: 1.105-2.665, P=0.016) more likely. The results of our study suggest that post-transplant elevated serum uric acid level is an independent predictor of long-term graft survival and graft function. Together with the high TG level impact on poor outcomes, further investigations for therapeutic effect are needed. PMID:26208103

Individual and Community Level Risk-Factors for Alcohol Use Disorder among Conflict-Affected Persons in Georgia

PubMed Central

Roberts, Bayard; Murphy, Adrianna; Chikovani, Ivdity; Makhashvili, Nino; Patel, Vikram; McKee, Martin

2014-01-01

Background The evidence on alcohol use disorder among conflict-affected civilian populations remains extremely weak, despite a number of potential risk-factors. The aim of this study is to examine patterns of alcohol use disorder among conflict-affected persons in the Republic of Georgia. Methods A cross-sectional survey of 3600 randomly selected internally displaced persons (IDPs) and former IDPs. Two alcohol use disorder outcomes were measured: (i) having at least hazardous alcohol use (AUDIT score ≥8); (ii) episodic heavy drinking (consuming >60 grams of pure alcohol per drinking session at least once a week). Individual level demographic and socio-economic characteristics were also recorded, including mental disorders. Community level alcohol environment characteristics relating to alcohol availability, marketing and pricing were recorded in the respondents' communities and a factor analysis conducted to produce a summary alcohol environment factor score. Logistic regression analyses examined associations between individual and community level factors with the alcohol use disorder outcomes (among men only). Results Of the total sample, 71% of men and 16% of women were current drinkers. Of the current drinkers (N = 1386), 28% of men and 1% of women were classified as having at least hazardous alcohol use; and 12% of men and 2% of women as episodic heavy drinkers. Individual characteristics significantly associated with both outcomes were age and experiencing a serious injury, while cumulative trauma events and depression were also associated with having at least hazardous alcohol use. For the community level analysis, a one unit increase in the alcohol environment factor was associated with a 1.27 fold increase in episodic heavy drinking among men (no significant association with hazardous alcohol use). Conclusion The findings suggest potential synergies for treatment responses for alcohol use disorder and depression among conflict-affected populations in Georgia, as well as the need for stronger alcohol control policies in Georgia. PMID:24865450

The risk of falling into poverty after developing heart disease: a survival analysis.

PubMed

Callander, Emily J; Schofield, Deborah J

2016-07-15

Those with a low income are known to have a higher risk of developing heart disease. However, the inverse relationship - falling into income poverty after developing heart disease has not been explored with longitudinal data. This paper aims to determine if those with heart disease have an elevated risk of falling into poverty. Survival analysis was conducted using the longitudinal Household Income and Labour Dynamics in Australia survey, between the years 2007 and 2012. The study focused on the Australian population aged 21 years and over in 2007 who were not already in poverty and did not already have heart disease, who were followed from 2007 to 2012. Cox regression models adjusting for age, sex and time-varying co-variates (marital status, home ownership and remoteness of area of residence) were constructed to assess the risk of falling into poverty. For those aged 20 who developed heart disease, the hazard ratio for falling into income poverty was 9.24 (95 % CI: 8.97-9.51) and for falling into multidimensional poverty the hazard ratio was 14.21 (95 % CI: 13.76-14.68); for those aged 40 the hazard ratio for falling into income poverty was 3.45 (95 % CI: 3.39-3.51) and for multidimensional poverty, 5.20 (95 % CI: 5.11-5.29); and for those aged 60 the hazard ratio for falling into income poverty was 1.29 (95 % CI: 1.28-1.30) and for multidimensional poverty, 1.52 (95 % CI: 1.51-1.54), relative those who never developed heart disease. The risk for both income and multidimensional poverty decreases with age up to the age of 70, over which, those who developed heart disease had a reduced risk of poverty. For those under the age of 70, developing heart disease is associated with an increased risk of falling into both income poverty and multidimensional poverty.

Can the provision of a home help service for the elderly population reduce the incidence of fall-related injuries? A quasi-experimental study of the community-level effects on hospital admissions in Swedish municipalities.

PubMed

Bonander, Carl; Gustavsson, Johanna; Nilson, Finn

2016-12-01

Fall-related injuries are a global public health problem, especially in elderly populations. The effect of an intervention aimed at reducing the risk of falls in the homes of community-dwelling elderly persons was evaluated. The intervention mainly involves the performance of complicated tasks and hazards assessment by a trained assessor, and has been adopted gradually over the last decade by 191 of 290 Swedish municipalities. A quasi-experimental design was used where intention-to-treat effect estimates were derived using panel regression analysis and a regression discontinuity (RD) design. The outcome measure was the incidence of fall-related hospitalisations in the treatment population, the age of which varied by municipality (≥65 years, ≥67 years, ≥70 years or ≥75 years). We found no statistically significant reductions in injury incidence in the panel regression (IRR 1.01 (95% CI 0.98 to 1.05)) or RD (IRR 1.00 (95% CI 0.97 to 1.03)) analyses. The results are robust to several different model specifications, including segmented panel regression analysis with linear trend change and community fixed effects parameters. It is unclear whether the absence of an effect is due to a low efficacy of the services provided, or a result of low adherence. Additional studies of the effects on other quality-of-life measures are recommended before conclusions are drawn regarding the cost-effectiveness of the provision of home help service programmes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

High lncRNA H19 expression as prognostic indicator: data mining in female cancers and polling analysis in non-female cancers

PubMed Central

Peng, Li; Liu, Zhao-Yang; Li, Wen-Ling; Zhang, Chao-Yang; Zhang, Ya-Qin; Pan, Xi; Chen, Jun; Li, Yue-Hui

2017-01-01

Upregulation of lncRNA H19 expression is associated with an unfavorable prognosis in some cancers. However, the prognostic value of H19 in female-specific cancers has remained uncharacterized. In this study, the prognostic power of high H19 expression in female cancer patients from the TCGA datasets was analyzed using Kaplan-Meier survival curves and Cox's proportional hazard modeling. In addition, in a meta-analysis of non-female cancer patients from TCGA datasets and 12 independent studies, hazard ratios (HRs) with 95% confidence interval (CI) for overall survival (OS) and disease-free survival (DFS)/relapse-free survival (RFS)/metastasis-free survival (MFS)/progression-free survival (PFS) were pooled to assess the prognostic value of high H19 expression. Kaplan-Meier analysis revealed that patients with uterine corpus cancer and higher H19 expression had a shorter OS (HR=2.710, p<0.05), while females with cervical cancer and increased H19 expression had a shorter RFS (HR=2.261, p<0.05). Multivariate Cox regression analysis showed that high H19 expression could independently predict a poorer prognosis in cervical cancer patients (HR=4.099, p<0.05). In the meta-analysis, patients with high H19 expression showed a poorer outcome in non-female cancer (p<0.05). These results suggest that high lncRNA H19 expression is predictive of an unfavorable prognosis in two female cancers (uterine corpus endometrioid cancer and cervical cancer) as well as in non-female cancer patients. PMID:27926484

High lncRNA H19 expression as prognostic indicator: data mining in female cancers and polling analysis in non-female cancers.

PubMed

Peng, Li; Yuan, Xiao-Qing; Liu, Zhao-Yang; Li, Wen-Ling; Zhang, Chao-Yang; Zhang, Ya-Qin; Pan, Xi; Chen, Jun; Li, Yue-Hui; Li, Guan-Cheng

2017-01-03

Upregulation of lncRNA H19 expression is associated with an unfavorable prognosis in some cancers. However, the prognostic value of H19 in female-specific cancers has remained uncharacterized. In this study, the prognostic power of high H19 expression in female cancer patients from the TCGA datasets was analyzed using Kaplan-Meier survival curves and Cox's proportional hazard modeling. In addition, in a meta-analysis of non-female cancer patients from TCGA datasets and 12 independent studies, hazard ratios (HRs) with 95% confidence interval (CI) for overall survival (OS) and disease-free survival (DFS)/relapse-free survival (RFS)/metastasis-free survival (MFS)/progression-free survival (PFS) were pooled to assess the prognostic value of high H19 expression. Kaplan-Meier analysis revealed that patients with uterine corpus cancer and higher H19 expression had a shorter OS (HR=2.710, p<0.05), while females with cervical cancer and increased H19 expression had a shorter RFS (HR=2.261, p<0.05). Multivariate Cox regression analysis showed that high H19 expression could independently predict a poorer prognosis in cervical cancer patients (HR=4.099, p<0.05). In the meta-analysis, patients with high H19 expression showed a poorer outcome in non-female cancer (p<0.05). These results suggest that high lncRNA H19 expression is predictive of an unfavorable prognosis in two female cancers (uterine corpus endometrioid cancer and cervical cancer) as well as in non-female cancer patients.

CREATION OF A MODEL TO PREDICT SURVIVAL IN PATIENTS WITH REFRACTORY COELIAC DISEASE USING A MULTINATIONAL REGISTRY

PubMed Central

Rubio-Tapia, Alberto; Malamut, Georgia; Verbeek, Wieke H.M.; van Wanrooij, Roy L.J.; Leffler, Daniel A.; Niveloni, Sonia I.; Arguelles-Grande, Carolina; Lahr, Brian D.; Zinsmeister, Alan R.; Murray, Joseph A.; Kelly, Ciaran P.; Bai, Julio C.; Green, Peter H.; Daum, Severin; Mulder, Chris J.J.; Cellier, Christophe

2016-01-01

Background Refractory coeliac disease is a severe complication of coeliac disease with heterogeneous outcome. Aim To create a prognostic model to estimate survival of patients with refractory coeliac disease. Methods We evaluated predictors of 5-year mortality using Cox proportional hazards regression on subjects from a multinational registry. Bootstrap re-sampling was used to internally validate the individual factors and overall model performance. The mean of the estimated regression coefficients from 400 bootstrap models was used to derive a risk score for 5-year mortality. Results The multinational cohort was composed of 232 patients diagnosed with refractory coeliac disease across 7 centers (range of 11–63 cases per center). The median age was 53 years and 150 (64%) were women. A total of 51 subjects died during 5-year follow-up (cumulative 5-year all-cause mortality = 30%). From a multiple variable Cox proportional hazards model, the following variables were significantly associated with 5-year mortality: age at refractory coeliac disease diagnosis (per 20 year increase, hazard ratio = 2.21; 95% confidence interval: 1.38, 3.55), abnormal intraepithelial lymphocytes (hazard ratio = 2.85; 95% confidence interval: 1.22, 6.62), and albumin (per 0.5 unit increase, hazard ratio = 0.72; 95% confidence interval: 0.61, 0.85). A simple weighted 3-factor risk score was created to estimate 5-year survival. Conclusions Using data from a multinational registry and previously-reported risk factors, we create a prognostic model to predict 5-year mortality among patients with refractory coeliac disease. This new model may help clinicians to guide treatment and follow-up. PMID:27485029

Creation of a model to predict survival in patients with refractory coeliac disease using a multinational registry.

PubMed

Rubio-Tapia, A; Malamut, G; Verbeek, W H M; van Wanrooij, R L J; Leffler, D A; Niveloni, S I; Arguelles-Grande, C; Lahr, B D; Zinsmeister, A R; Murray, J A; Kelly, C P; Bai, J C; Green, P H; Daum, S; Mulder, C J J; Cellier, C

2016-10-01

Refractory coeliac disease is a severe complication of coeliac disease with heterogeneous outcome. To create a prognostic model to estimate survival of patients with refractory coeliac disease. We evaluated predictors of 5-year mortality using Cox proportional hazards regression on subjects from a multinational registry. Bootstrap resampling was used to internally validate the individual factors and overall model performance. The mean of the estimated regression coefficients from 400 bootstrap models was used to derive a risk score for 5-year mortality. The multinational cohort was composed of 232 patients diagnosed with refractory coeliac disease across seven centres (range of 11-63 cases per centre). The median age was 53 years and 150 (64%) were women. A total of 51 subjects died during a 5-year follow-up (cumulative 5-year all-cause mortality = 30%). From a multiple variable Cox proportional hazards model, the following variables were significantly associated with 5-year mortality: age at refractory coeliac disease diagnosis (per 20 year increase, hazard ratio = 2.21; 95% confidence interval, CI: 1.38-3.55), abnormal intraepithelial lymphocytes (hazard ratio = 2.85; 95% CI: 1.22-6.62), and albumin (per 0.5 unit increase, hazard ratio = 0.72; 95% CI: 0.61-0.85). A simple weighted three-factor risk score was created to estimate 5-year survival. Using data from a multinational registry and previously reported risk factors, we create a prognostic model to predict 5-year mortality among patients with refractory coeliac disease. This new model may help clinicians to guide treatment and follow-up. © 2016 John Wiley & Sons Ltd.

Value of sentinel lymph node biopsy and adjuvant interferon treatment in thick (>4 mm) cutaneous melanoma: an observational study.

PubMed

Morera-Sendra, Natalia; Tejera-Vaquerizo, Antonio; Traves, Víctor; Requena, Celia; Bolumar, Isidro; Pla, Angel; Vázquez, Carlos; Soriano, Virtudes; Nagore, Eduardo

2016-01-01

The role of sentinel lymph node biopsy and the benefit of immunotherapy with interferon in thick (>4 mm) melanomas remain uncertain. Our aim was to assess the value of both sentinel lymph node (SLN) biopsy and immunotherapy in the prognosis of thick melanomas. A retrospective study based on a computerized patient database in which patients have been prospectively collected since 2005 was performed. Age, sex, location, Breslow thickness, tumor ulceration, regression, Clark level, tumor infiltrating lymphocytes, tumor mitotic rate, microscopic satellite and vascular invasion were included in the analysis. Disease-free (DFS), disease-specific (DSS) and overall (OS) survivals were evaluated by the Kaplan-Meier method and Cox regression analysis. A series of 141 patients with melanomas thicker than 4 mm were included. Multivariate regression showed a worse prognosis in SLN-positive patients with respect to SLN biopsy-negative patients (DFS, hazard ratio [HR] 2, p = 0.04; DSS, HR 2.2, p = 0.002; OS, HR 2.4, p = 0.02). The observational group was shown to have a worse prognosis than the SLN-positive group but was very similar to the clinically positive group. Immunotherapy with high-dose interferon showed a protective effect (DFS, HR 0.5, p = 0.02; DSS, HR 0.3, p = 0.001; OS, HR 0.3, p = 0.001). Our data indicate that SLN biopsy and adjuvant interferon should be considered for patients with thick melanomas.

Prognostic and survival analysis of 837 Chinese colorectal cancer patients.

PubMed

Yuan, Ying; Li, Mo-Dan; Hu, Han-Guang; Dong, Cai-Xia; Chen, Jia-Qi; Li, Xiao-Fen; Li, Jing-Jing; Shen, Hong

2013-05-07

To develop a prognostic model to predict survival of patients with colorectal cancer (CRC). Survival data of 837 CRC patients undergoing surgery between 1996 and 2006 were collected and analyzed by univariate analysis and Cox proportional hazard regression model to reveal the prognostic factors for CRC. All data were recorded using a standard data form and analyzed using SPSS version 18.0 (SPSS, Chicago, IL, United States). Survival curves were calculated by the Kaplan-Meier method. The log rank test was used to assess differences in survival. Univariate hazard ratios and significant and independent predictors of disease-specific survival and were identified by Cox proportional hazard analysis. The stepwise procedure was set to a threshold of 0.05. Statistical significance was defined as P < 0.05. The survival rate was 74% at 3 years and 68% at 5 years. The results of univariate analysis suggested age, preoperative obstruction, serum carcinoembryonic antigen level at diagnosis, status of resection, tumor size, histological grade, pathological type, lymphovascular invasion, invasion of adjacent organs, and tumor node metastasis (TNM) staging were positive prognostic factors (P < 0.05). Lymph node ratio (LNR) was also a strong prognostic factor in stage III CRC (P < 0.0001). We divided 341 stage III patients into three groups according to LNR values (LNR1, LNR ≤ 0.33, n = 211; LNR2, LNR 0.34-0.66, n = 76; and LNR3, LNR ≥ 0.67, n = 54). Univariate analysis showed a significant statistical difference in 3-year survival among these groups: LNR1, 73%; LNR2, 55%; and LNR3, 42% (P < 0.0001). The multivariate analysis results showed that histological grade, depth of bowel wall invasion, and number of metastatic lymph nodes were the most important prognostic factors for CRC if we did not consider the interaction of the TNM staging system (P < 0.05). When the TNM staging was taken into account, histological grade lost its statistical significance, while the specific TNM staging system showed a statistically significant difference (P < 0.0001). The overall survival of CRC patients has improved between 1996 and 2006. LNR is a powerful factor for estimating the survival of stage III CRC patients.

TU-CD-BRB-08: Radiomic Analysis of FDG-PET Identifies Novel Prognostic Imaging Biomarkers in Locally Advanced Pancreatic Cancer Patients Treated with SBRT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cui, Y; Shirato, H; Song, J

2015-06-15

Purpose: This study aims to identify novel prognostic imaging biomarkers in locally advanced pancreatic cancer (LAPC) using quantitative, high-throughput image analysis. Methods: 86 patients with LAPC receiving chemotherapy followed by SBRT were retrospectively studied. All patients had a baseline FDG-PET scan prior to SBRT. For each patient, we extracted 435 PET imaging features of five types: statistical, morphological, textural, histogram, and wavelet. These features went through redundancy checks, robustness analysis, as well as a prescreening process based on their concordance indices with respect to the relevant outcomes. We then performed principle component analysis on the remaining features (number ranged frommore » 10 to 16), and fitted a Cox proportional hazard regression model using the first 3 principle components. Kaplan-Meier analysis was used to assess the ability to distinguish high versus low-risk patients separated by median predicted survival. To avoid overfitting, all evaluations were based on leave-one-out cross validation (LOOCV), in which each holdout patient was assigned to a risk group according to the model obtained from a separate training set. Results: For predicting overall survival (OS), the most dominant imaging features were wavelet coefficients. There was a statistically significant difference in OS between patients with predicted high and low-risk based on LOOCV (hazard ratio: 2.26, p<0.001). Similar imaging features were also strongly associated with local progression-free survival (LPFS) (hazard ratio: 1.53, p=0.026) on LOOCV. In comparison, neither SUVmax nor TLG was associated with LPFS (p=0.103, p=0.433) (Table 1). Results for progression-free survival and distant progression-free survival showed similar trends. Conclusion: Radiomic analysis identified novel imaging features that showed improved prognostic value over conventional methods. These features characterize the degree of intra-tumor heterogeneity reflected on FDG-PET images, and their biological underpinnings warrant further investigation. If validated in large, prospective cohorts, this method could be used to stratify patients based on individualized risk.« less

Survival time and effect of selected predictor variables on survival in owned pet cats seropositive for feline immunodeficiency and leukemia virus attending a referral clinic in northern Italy.

PubMed

Spada, Eva; Perego, Roberta; Sgamma, Elena Assunta; Proverbio, Daniela

2018-02-01

Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) are among the most important feline infectious diseases worldwide. This retrospective study investigated survival times and effects of selected predictor factors on survival time in a population of owned pet cats in Northern Italy testing positive for the presence of FIV antibodies and FeLV antigen. One hundred and three retrovirus-seropositive cats, 53 FIV-seropositive cats, 40 FeLV-seropositive cats, and 10 FIV+FeLV-seropositive cats were included in the study. A population of 103 retrovirus-seronegative age and sex-matched cats was selected. Survival time was calculated and compared between retrovirus-seronegative, FIV, FeLV and FIV+FeLV-seropositive cats using Kaplan-Meier survival analysis. Cox proportional-hazards regression analysis was used to study the effect of selected predictor factors (male gender, peripheral blood cytopenia as reduced red blood cells - RBC- count, leukopenia, neutropenia and lymphopenia, hypercreatininemia and reduced albumin to globulin ratio) on survival time in retrovirus-seropositive populations. Median survival times for seronegative cats, FIV, FeLV and FIV+FeLV-seropositive cats were 3960, 2040, 714 and 77days, respectively. Compared to retrovirus-seronegative cats median survival time was significantly lower (P<0.000) in FeLV and FIV+FeLV-seropositive cats. Median survival time in FeLV and FIV+FeLV-seropositive cats was also significant lower (P<0.000) when compared to FIV-seropositive cats. Hazard ratio of death in FeLV and FIV+FeLV-seropositive cats being respectively 3.4 and 7.4 times higher, in comparison to seronegative cats and 2.3 and 4.8 times higher in FeLV and FIV+FeLV-seropositive cats as compared to FIV-seropositive cats. A Cox proportional-hazards regression analysis showed that FIV and FeLV-seropositive cats with reduced RBC counts at time of diagnosis of seropositivity had significantly shorter survival times when compared to FIV and FeLV-seropositive cats with normal RBC counts at diagnosis. In summary, FIV-seropositive status did not significantly affect longevity of cats in this study, unlike FeLV and FIV+FeLV-seropositivity. Reduced RBC counts at time of FIV and FeLV diagnosis could impact negatively on the longevity of seropositive cats and therefore blood counts should always be evaluated at diagnosis and follow-up of retrovirus-seropositive cats. Copyright © 2017 Elsevier B.V. All rights reserved.

The association between crowding and mortality in admitted pediatric patients from mixed adult-pediatric emergency departments in Korea.

PubMed

Cha, Won Chul; Shin, Sang Do; Cho, Jin Sung; Song, Kyoung Jun; Singer, Adam J; Kwak, Young Ho

2011-12-01

We aimed to investigate the effect of crowding on the hospital mortality of pediatric patients from adult-pediatric mixed emergency departments (EDs). We used the National Emergency Department Information System database, which included demographic, clinical, diagnostic, and procedural information with all emergency patients visiting to 116 EDs from Korea since 2004. We enrolled EDs with mean length of stay of more than 6 hours. Study period was from January 2006 to December 2008. Pediatric patients younger than 15 years admitted from these EDs were study targets. We calculated the mean patient volume (mean number of patients in the ED) over 8-hour shift for each hospital. When the volume reached the highest quartile, the period was considered as crowded. Patients who came during the overcrowded period were defined as the crowded group. We performed a Kaplan-Meier analysis, and hazard ratio and 95% confidence intervals (95% CIs) were calculated using a Cox proportional hazards regression model. A total of 34 EDs and 125,031 admitted pediatric patients were included; 74,152 (59.3%) were male, and the mean age was 3.84 (95% CI, 3.82-3.86) years; 35,924 (28.7%) were determined as the crowded group. The 30-day mortality rates were 0.4% and 0.3% (P = 0.063) for the crowded group and for the noncrowded group, respectively. The hazard ratio for hospital mortality of the crowded group was 1.230 (95% CI, 1.019-1.558). The ED crowding was associated with increased hazard for hospital mortality for pediatric patients in mixed EDs.

A higher incidence rate of acute coronary syndrome following radiation therapy in patients with breast cancer and a history of coronary artery diseases.

PubMed

Lee, Yen-Chien; Chuang, Jen-Pin; Hsieh, Pi-Ching; Chiou, Meng-Jiun; Li, Chung-Yi

2015-07-01

This study aims to investigate whether patients with breast cancer and a history of cardiovascular diseases (CADs) are at an increased incidence of acute coronary syndrome (ACS) after receiving radiation therapy (RT). In Taiwan, 5828 patients who had a history of CAD were newly diagnosed of breast cancer and received mastectomy between 1999 and 2009. Among these patients, 1851 also received RT. The study cohort was prospectively followed to the end of 2010 for estimating the incidence of ACS in association with exposure to RT. A Cox proportional hazard model that was adjusted for covariates was used to estimate the hazard ratio (HR) of ACS. Over the study period, the incident rates of ACS for RT and control patients were estimated at 1.51 and 1.77 per 100 person-years, respectively. Covariate-adjusted regression analysis indicated that the hazard of ACS significantly increased in RT patients at an adjusted HR of 1.48 [95% confidence interval (CI) 1.18-1.87]. Both hypertension and diabetes significantly increased the hazard of ACS in this patient cohort, with adjusted HRs of 3.31 (95% CI 1.94-5.66) and 1.50 (95% CI 1.19-1.89), respectively. This 12-year follow-up study suggested excess of ACS events in association with RT exposure in patients with breast cancer who had a higher cardiovascular risk. In consideration of the benefit associated with RT, intensive cardiac care should be given to patients with breast cancer and high cardiovascular risk.

Modeling rain-fed maize vulnerability to droughts using the standardized precipitation index from satellite estimated rainfall—Southern Malawi case study

USGS Publications Warehouse

Funk, Christopher C.; Verdin, James; Adams Chavula,; Gregory J. Husak,; Harikishan Jayanthi,; Tamuka Magadzire,

2013-01-01

During 1990s, disaster risk reduction emerged as a novel, proactive approach to managing risks from natural hazards. The World Bank, USAID, and other international donor agencies began making efforts to mainstream disaster risk reduction in countries whose population and economies were heavily dependent on rain-fed agriculture. This approach has more significance in light of the increasing climatic hazard patterns and the climate scenarios projected for different hazard prone countries in the world. The Famine Early Warning System Network (FEWS NET) has been monitoring the food security issues in the sub-Saharan Africa, Asia and in Haiti. FEWS NET monitors the rainfall and moisture availability conditions with the help of NOAA RFE2 data for deriving food security status in Africa. This paper highlights the efforts in using satellite estimated rainfall inputs to develop drought vulnerability models in the drought prone areas in Malawi. The satellite RFE2 based SPI corresponding to the critical tasseling and silking phases (in the months of January, February, and March) were statistically regressed with drought-induced yield losses at the district level. The analysis has shown that the drought conditions in February and early March lead to most damage to maize yields in this region. The district-wise vulnerabilities to drought were upscaled to obtain a regional maize vulnerability model for southern Malawi. The results would help in establishing an early monitoring mechanism for drought impact assessment, give the decision makers additional time to assess seasonal outcomes, and identify potential food-related hazards in Malawi.

Factors associated with alcohol use prior to and during pregnancy among HIV-infected pregnant women in Cape Town, South Africa

PubMed Central

Brittain, Kirsty; Remien, Robert H.; Phillips, Tamsin; Zerbe, Allison; Abrams, Elaine J.; Myer, Landon; Mellins, Claude A.

2017-01-01

Introduction Alcohol use during pregnancy is prevalent in South Africa, but there are few prospectively-collected data exploring patterns of consumption among HIV-infected women, which may be important to improve maternal and child health outcomes. We examined patterns of and factors associated with alcohol use prior to and during pregnancy among HIV-infected pregnant women in Cape Town, South Africa. Methods Participants were enrolled when entering antenatal care at a large primary care clinic, and alcohol use was assessed using the AUDIT (Alcohol Use Disorders Identification Test). In analysis, the AUDIT-C scoring was used as a measure of hazardous drinking, and we examined factors associated with patterns of alcohol use in logistic regression models. Results Among 580 women (median age: 28.1 years), 40% reported alcohol use during the 12 months prior to pregnancy, with alcohol use characterised by binge drinking and associated with single relationship status, experience of intimate partner violence (IPV), and lower levels of HIV-related stigma. Of this group, 65% had AUDIT-C scores suggesting hazardous alcohol use, with hazardous alcohol users more likely to report having experienced IPV and having higher levels of education. Among hazardous alcohol users, 70% subsequently reported reduced levels of consumption during pregnancy. Factors independently associated with reduced consumption included earlier gestation when entering antenatal care and report of a better patient-healthcare provider relationship. Conclusions These unique data provide important insights into alcohol use trajectories in this context, and highlight the urgent need for an increased focus on screening and intervention at primary care level. PMID:28199918

Vulnerability survival analysis: a novel approach to vulnerability management

NASA Astrophysics Data System (ADS)

Farris, Katheryn A.; Sullivan, John; Cybenko, George

2017-05-01

Computer security vulnerabilities span across large, enterprise networks and have to be mitigated by security engineers on a routine basis. Presently, security engineers will assess their "risk posture" through quantifying the number of vulnerabilities with a high Common Vulnerability Severity Score (CVSS). Yet, little to no attention is given to the length of time by which vulnerabilities persist and survive on the network. In this paper, we review a novel approach to quantifying the length of time a vulnerability persists on the network, its time-to-death, and predictors of lower vulnerability survival rates. Our contribution is unique in that we apply the cox proportional hazards regression model to real data from an operational IT environment. This paper provides a mathematical overview of the theory behind survival analysis methods, a description of our vulnerability data, and an interpretation of the results.

Reported Theory Use by Digital Interventions for Hazardous and Harmful Alcohol Consumption, and Association With Effectiveness: Meta-Regression

PubMed Central

Crane, David; Brown, Jamie; Kaner, Eileen; Beyer, Fiona; Muirhead, Colin; Hickman, Matthew; Redmore, James; de Vocht, Frank; Beard, Emma; Michie, Susan

2018-01-01

Background Applying theory to the design and evaluation of interventions is likely to increase effectiveness and improve the evidence base from which future interventions are developed, though few interventions report this. Objective The aim of this paper was to assess how digital interventions to reduce hazardous and harmful alcohol consumption report the use of theory in their development and evaluation, and whether reporting of theory use is associated with intervention effectiveness. Methods Randomized controlled trials were extracted from a Cochrane review on digital interventions for reducing hazardous and harmful alcohol consumption. Reporting of theory use within these digital interventions was investigated using the theory coding scheme (TCS). Reported theory use was analyzed by frequency counts and descriptive statistics. Associations were analyzed with meta-regression models. Results Of 41 trials involving 42 comparisons, half did not mention theory (50% [21/42]), and only 38% (16/42) used theory to select or develop the intervention techniques. Significant heterogeneity existed between studies in the effect of interventions on alcohol reduction (I2=77.6%, P<.001). No significant associations were detected between reporting of theory use and intervention effectiveness in unadjusted models, though the meta-regression was underpowered to detect modest associations. Conclusions Digital interventions offer a unique opportunity to refine and develop new dynamic, temporally sensitive theories, yet none of the studies reported refining or developing theory. Clearer selection, application, and reporting of theory use is needed to accurately assess how useful theory is in this field and to advance the field of behavior change theories. PMID:29490895

14 CFR 417.227 - Toxic release hazard analysis.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Toxic release hazard analysis. 417.227..., DEPARTMENT OF TRANSPORTATION LICENSING LAUNCH SAFETY Flight Safety Analysis § 417.227 Toxic release hazard analysis. A flight safety analysis must establish flight commit criteria that protect the public from any...

On estimation of linear transformation models with nested case–control sampling

PubMed Central

Liu, Mengling

2011-01-01

Nested case–control (NCC) sampling is widely used in large epidemiological cohort studies for its cost effectiveness, but its data analysis primarily relies on the Cox proportional hazards model. In this paper, we consider a family of linear transformation models for analyzing NCC data and propose an inverse selection probability weighted estimating equation method for inference. Consistency and asymptotic normality of our estimators for regression coefficients are established. We show that the asymptotic variance has a closed analytic form and can be easily estimated. Numerical studies are conducted to support the theory and an application to the Wilms’ Tumor Study is also given to illustrate the methodology. PMID:21912975

Association between Daily Hospital Outpatient Visits for Accidents and Daily Ambient Air Temperatures in an Industrial City.

PubMed

Chau, Tang-Tat; Wang, Kuo-Ying

2016-01-01

An accident is an unwanted hazard to a person. However, accidents occur. In this work, we search for correlations between daily accident rates and environmental factors. To study daily hospital outpatients who were admitted for accidents during a 5-year period, 2007-2011, we analyzed data regarding 168,366 outpatients using univariate regression models; we also used multivariable regression models to account for confounding factors. Our analysis indicates that the number of male outpatients admitted for accidents was approximately 1.31 to 1.47 times the number of female outpatients (P < 0.0001). Of the 12 parameters (regarding air pollution and meteorology) considered, only daily temperature exhibited consistent and significant correlations with the daily number of hospital outpatient visits for accidents throughout the 5-year analysis period. The univariate regression models indicate that older people (greater than 66 years old) had the fewest accidents per 1-degree increase in temperature, followed by young people (0-15 years old). Middle-aged people (16-65 years old) were the group of outpatients that were more prone to accidents, with an increase in accident rates of 0.8-1.2 accidents per degree increase in temperature. The multivariable regression models also reveal that the temperature variation was the dominant factor in determining the daily number of outpatient visits for accidents. Our further multivariable model analysis of temperature with respect to air pollution variables show that, through the increases in emissions and concentrations of CO, photochemical O3 production and NO2 loss in the ambient air, increases in vehicular emissions are associated with increases in temperatures. As such, increases in hospital visits for accidents are related to vehicular emissions and usage. This finding is consistent with clinical experience which shows about 60% to 80% of accidents are related to traffic, followed by accidents occurred in work place.

Association between Daily Hospital Outpatient Visits for Accidents and Daily Ambient Air Temperatures in an Industrial City

PubMed Central

Chau, Tang-Tat; Wang, Kuo-Ying

2016-01-01

An accident is an unwanted hazard to a person. However, accidents occur. In this work, we search for correlations between daily accident rates and environmental factors. To study daily hospital outpatients who were admitted for accidents during a 5-year period, 2007–2011, we analyzed data regarding 168,366 outpatients using univariate regression models; we also used multivariable regression models to account for confounding factors. Our analysis indicates that the number of male outpatients admitted for accidents was approximately 1.31 to 1.47 times the number of female outpatients (P < 0.0001). Of the 12 parameters (regarding air pollution and meteorology) considered, only daily temperature exhibited consistent and significant correlations with the daily number of hospital outpatient visits for accidents throughout the 5-year analysis period. The univariate regression models indicate that older people (greater than 66 years old) had the fewest accidents per 1-degree increase in temperature, followed by young people (0–15 years old). Middle-aged people (16–65 years old) were the group of outpatients that were more prone to accidents, with an increase in accident rates of 0.8–1.2 accidents per degree increase in temperature. The multivariable regression models also reveal that the temperature variation was the dominant factor in determining the daily number of outpatient visits for accidents. Our further multivariable model analysis of temperature with respect to air pollution variables show that, through the increases in emissions and concentrations of CO, photochemical O3 production and NO2 loss in the ambient air, increases in vehicular emissions are associated with increases in temperatures. As such, increases in hospital visits for accidents are related to vehicular emissions and usage. This finding is consistent with clinical experience which shows about 60% to 80% of accidents are related to traffic, followed by accidents occurred in work place. PMID:26815039

Soccer and sexual health education: a promising approach for reducing adolescent births in Haiti.

PubMed

Kaplan, Kathryn C; Lewis, Judy; Gebrian, Bette; Theall, Katherine

2015-05-01

To explore the effect of an innovative, integrative program in female sexual reproductive health (SRH) and soccer (or fútbol, in Haitian Creole) in rural Haiti by measuring the rate of births among program participants 15-19 years old and their nonparticipant peers. A retrospective cohort study using 2006-2009 data from the computerized data-tracking system of the Haitian Health Foundation (HHF), a U.S.-based nongovernmental organization serving urban and rural populations in Haiti, was used to assess births among girls 15-19 years old who participated in HHF's GenNext program, a combination education-soccer program for youth, based on SRH classes HHF nurses and community workers had been conducting in Haiti for mothers, fathers, and youth; girl-centered health screenings; and an all-female summer soccer league, during 2006-2009 (n = 4 251). Bivariate and multiple logistic regression analyses were carried out to assess differences in the rate of births among program participants according to their level of participation (SRH component only ("EDU") versus both the SRH and soccer components ("SO") compared to their village peers who did not participate. Hazard ratios (HRs) of birth rates were estimated using Cox regression analysis of childbearing data for the three different groups. In the multiple logistic regression analysis, only the girls in the "EDU" group had significantly fewer births than the nonparticipants after adjusting for confounders (odds ratio = 0.535; 95% confidence interval (CI) = 0.304, 0.940). The Cox regression analysis demonstrated that those in the EDU group (HR = 0.893; 95% CI = 0.802, 0.994) and to a greater degree those in the SO group (HR = 0.631; 95% CI = 0.558, 0.714) were significantly protected against childbearing between the ages of 15 and 19 years. HHF's GenNext program demonstrates the effectiveness of utilizing nurse educators, community mobilization, and youth participation in sports, education, and structured youth groups to promote and sustain health for adolescent girls and young women.

Oligoclonal bands predict multiple sclerosis in children with optic neuritis.

PubMed

Heussinger, Nicole; Kontopantelis, Evangelos; Gburek-Augustat, Janina; Jenke, Andreas; Vollrath, Gesa; Korinthenberg, Rudolf; Hofstetter, Peter; Meyer, Sascha; Brecht, Isabel; Kornek, Barbara; Herkenrath, Peter; Schimmel, Mareike; Wenner, Kirsten; Häusler, Martin; Lutz, Soeren; Karenfort, Michael; Blaschek, Astrid; Smitka, Martin; Karch, Stephanie; Piepkorn, Martin; Rostasy, Kevin; Lücke, Thomas; Weber, Peter; Trollmann, Regina; Klepper, Jörg; Häussler, Martin; Hofmann, Regina; Weissert, Robert; Merkenschlager, Andreas; Buttmann, Mathias

2015-06-01

We retrospectively evaluated predictors of conversion to multiple sclerosis (MS) in 357 children with isolated optic neuritis (ON) as a first demyelinating event who had a median follow-up of 4.0 years. Multiple Cox proportional-hazards regressions revealed abnormal cranial magnet resonance imaging (cMRI; hazard ratio [HR] = 5.94, 95% confidence interval [CI] = 3.39-10.39, p < 0.001), presence of cerebrospinal fluid immunoglobulin G oligoclonal bands (OCB; HR = 3.69, 95% CI = 2.32-5.86, p < 0.001), and age (HR = 1.08 per year of age, 95% CI = 1.02-1.13, p = 0.003) as independent predictors of conversion, whereas sex and laterality (unilateral vs bilateral) had no influence. Combined cMRI and OCB positivity indicated a 26.84-fold higher HR for developing MS compared to double negativity (95% CI = 12.26-58.74, p < 0.001). Accordingly, cerebrospinal fluid analysis may supplement cMRI to determine the risk of MS in children with isolated ON. © 2015 American Neurological Association.

Osteoporosis in adult patients with atopic dermatitis: A nationwide population-based study

PubMed Central

Lu, Chun-Ching; Su, Yu-Feng; Tsai, Tai-Hsin; Wu, Chieh-Hsin

2017-01-01

The aim of this study was to investigate osteoporosis risk in atopic dermatitis (AD) patients. This study included patients in the Taiwan National Health Insurance Research dataset. The population-based study included all patients aged 20–49 years who had been diagnosed with AD during 1996–2010. In total, 35,229 age and gender-matched patients without AD in a 1:1 ratio were randomly selected as the non-AD group. Cox proportional-hazards regression and Kaplan–Meier analyses were used to measure the hazard ratios and the cumulative incidences of osteoporosis, respectively. During the follow-up period, 360(1.02%) AD patients and 127(0.36%) non-AD patients developed osteoporosis. The overall incidence of osteoporosis was4.72-fold greater in the AD patients compared to the non-AD patients (1.82 vs. 0.24 per 1,000 person-years, respectively) after adjusting for potential confounding factors. Osteoporosis risk factors included female gender, age, advanced Charlson Comorbidity Index, depression and use of corticosteroids. The dataset analysis showed that AD was significantly associated with subsequent risk of osteoporosis. PMID:28207767

Maternal and Neonatal Birth Factors Affecting the Age of ASD Diagnosis.

PubMed

Darcy-Mahoney, Ashley; Minter, Bonnie; Higgins, Melinda; Guo, Ying; Zauche, Lauren Head; Hirst, Jessica

2016-12-01

Early diagnosis of autism spectrum disorders (ASD) enables early intervention that improves long term functioning of children with ASD but is often delayed until age of school entry. Few studies have identified factors that affect timely diagnosis. This study addressed how maternal education, race, age, marital status as well as neonatal birth factors affect the age at which a child is diagnosed with ASD. This study involved a retrospective analysis of 664 records of children treated at one of the largest autism treatment centers in the United States from March 1, 2009 to December 30, 2010. Logistic regression and Cox proportional hazards regression were used to identify maternal and neonatal factors associated with age of diagnosis. Infant gender, maternal race, marital status, and maternal age were identified as significant factors for predicting the age of ASD diagnosis. In the Cox proportional hazards regression model, only maternal race and marital status were included. Median survival age till diagnosis of children born to married mothers was 53.4 months compared to 57.8 months and 63.7 months of children born to single and divorced or widowed mothers respectively. Median survival age till diagnosis for children of African American mothers was 53.8 months compared to 57.2 months for children of Caucasian mothers. No statistically significant difference of timing of ASD diagnosis was found for children of varying gestational age. Children born to older or married mothers and mothers of minority races were more likely to have an earlier ASD diagnosis. No statistically significant differences in timing of ASD diagnosis were found for children born at varying gestational ages. Identification of these factors has the potential to inform public health outreach aimed at promoting timely ASD diagnosis. This work could enhance clinical practice for timelier diagnoses of ASD by supporting parents and clinicians around the world in identifying risk factors beyond gender and SES and developing strategies to recognize earlier signs of ASD and contribute to improved development outcomes in children with ASD.

Role of Adjuvant Chemotherapy in ypT0-2N0 Patients Treated with Preoperative Chemoradiation Therapy and Radical Resection for Rectal Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, In Ja; Kim, Dae Yong; Kim, Hee Cheol

2015-07-01

Objective: To explore the role of adjuvant chemotherapy for patients with ypT0-2N0 rectal cancer treated by preoperative chemoradiation therapy (PCRT) and radical resection. Patients and Methods: A national consortium of 10 institutions was formed, and patients with ypT0-2N0 mid- and low-rectal cancer after PCRT and radical resection from 2004 to 2009 were included. Patients were categorized into 2 groups according to receipt of additional adjuvant chemotherapy: Adj CTx (+) versus Adj CTx (−). Propensity scores were calculated and used to perform matched and adjusted analyses comparing relapse-free survival (RFS) between treatment groups while controlling for potential confounding. Results: A totalmore » of 1016 patients, who met the selection criteria, were evaluated. Of these, 106 (10.4%) did not receive adjuvant chemotherapy. There was no overall improvement in 5-year RFS as a result of adjuvant chemotherapy [91.6% for Adj CTx (+) vs 87.5% for Adj CTx (−), P=.18]. There were no differences in 5-year local recurrence and distant metastasis rate between the 2 groups. In patients who show moderate, minimal, or no regression in tumor regression grade, however, possible association of adjuvant chemotherapy with RFS would be considered (hazard ratio 0.35; 95% confidence interval 0.14-0.88; P=.03). Cox regression analysis after propensity score matching failed to show that addition of adjuvant chemotherapy was associated with improved RFS (hazard ratio 0.81; 95% confidence interval 0.39-1.70; P=.58). Conclusions: Adjuvant chemotherapy seemed to not influence the RFS of patients with ypT0-2N0 rectal cancer after PCRT followed by radical resection. Thus, the addition of adjuvant chemotherapy needs to be weighed against its oncologic benefits.« less

Operating room-to-incision interval and neonatal outcome in emergency caesarean section: a retrospective 5-year cohort study.

PubMed

Palmer, E; Ciechanowicz, S; Reeve, A; Harris, S; Wong, D J N; Sultan, P

2018-07-01

We conducted a 5-year retrospective cohort study on women undergoing caesarean section to investigate factors influencing the operating room-to-incision interval. Time-to-event analysis was performed for category-1 caesarean section using a Cox proportional hazards regression model. Covariates included: anaesthetic technique; body mass index; age; parity; time of delivery; and gestational age. Binary logistic regression was performed for 5-min Apgar score ≥ 7. There were 677 women who underwent category-1 caesarean section and who met the entry criteria. Unadjusted median (IQR [range]) operating room-to-incision intervals were: epidural top-up 11 (7-17 [0-87]) min; general anaesthesia 6 (4-11 [0-69]) min; spinal 13 (10-20 [0-83]) min; and combined spinal-epidural 24 (13-35 [0-75]) min. Cox regression showed general anaesthesia to be the most rapid method with a hazard ratio (95%CI) of 1.97 (1.60-2.44; p < 0.0001), followed by epidural top-up (reference group), spinal anaesthesia 0.79 (0.65-0.96; p = 0.02) and combined spinal-epidural 0.48 (0.35-0.67; p < 0.0001). Underweight and overweight body mass indexes were associated with longer operating room-to-incision intervals. General anaesthesia was associated with fewer 5-min Apgar scores ≥ 7 with an odds ratio (95%CI) of 0.28 (0.11-0.68; p < 0.01). There was no difference in neonatal outcomes between the first and fifth quintiles for operating room-to-incision intervals. General anaesthesia is associated with the most rapid operating room-to-incision interval for category-1 caesarean section, but is also associated with worse short term neonatal outcomes. Longer operating room-to-incision intervals were not associated with worse neonatal outcomes. © 2018 The Association of Anaesthetists of Great Britain and Ireland.

Socioeconomic status inconsistency and risk of stroke among Japanese middle-aged women.

PubMed

Honjo, Kaori; Iso, Hiroyasu; Inoue, Manami; Sawada, Norie; Tsugane, Shoichiro

2014-09-01

Little research has been conducted to examine the effect of inconsistencies in socioeconomic status on cardiovascular health. In particular, no studies have been reported in Asian countries, including Japan, which is thought to have high socioeconomic status inconsistency among women. We examined the effect of status inconsistency between education level and occupation on stroke risk in a prospective 20-year study of 14 742 middle-aged Japanese women included in the prospective Japan Public Health Center-based (JPHC) Study Cohort I in 1990. Status inconsistency between education level and occupation was determined (qualified, overqualified, and underqualified), and the association with risk of stroke was examined. Cox proportional regression analysis was used to determine hazard ratios, which were adjusted for age, marital status, and geographical area. Adjusted hazard ratio for stroke in overqualified compared with qualified women was 2.06 (95% confidence interval, 1.13-3.78). Adjusted hazard ratios for stroke among highly educated manual workers and workers in service industry were 3.47 (95% confidence interval, 1.54-7.84) and 3.21 (95% confidence interval, 1.49-6.90), respectively, when compared with highly educated professionals/managers. High academic qualifications without an appropriate job could be a risk factor for stroke among Japanese women. Our result suggests that status inconsistency could be a potential explanation for the increased stroke risk among highly educated women. © 2014 American Heart Association, Inc.

Association of Severity of Coronary Artery Aneurysms in Patients With Kawasaki Disease and Risk of Later Coronary Events.

PubMed

Miura, Masaru; Kobayashi, Tohru; Kaneko, Tetsuji; Ayusawa, Mamoru; Fukazawa, Ryuji; Fukushima, Naoya; Fuse, Shigeto; Hamaoka, Kenji; Hirono, Keiichi; Kato, Taichi; Mitani, Yoshihide; Sato, Seiichi; Shimoyama, Shinya; Shiono, Junko; Suda, Kenji; Suzuki, Hiroshi; Maeda, Jun; Waki, Kenji; Kato, Hitoshi; Saji, Tsutomu; Yamagishi, Hiroyuki; Ozeki, Aya; Tomotsune, Masako; Yoshida, Makiko; Akazawa, Yohei; Aso, Kentaro; Doi, Shouzaburoh; Fukasawa, Yoshi; Furuno, Kenji; Hayabuchi, Yasunobu; Hayashi, Miyuki; Honda, Takafumi; Horita, Norihisa; Ikeda, Kazuyuki; Ishii, Masahiro; Iwashima, Satoru; Kamada, Masahiro; Kaneko, Masahide; Katyama, Hiroshi; Kawamura, Yoichi; Kitagawa, Atushi; Komori, Akiko; Kuraishi, Kenji; Masuda, Hiroshi; Matsuda, Shinichi; Matsuzaki, Satoshi; Mii, Sayaka; Miyamoto, Tomoyuki; Moritou, Yuji; Motoki, Noriko; Nagumo, Kiyoshi; Nakamura, Tsuneyuki; Nishihara, Eiki; Nomura, Yuichi; Ogata, Shohei; Ohashi, Hiroyuki; Okumura, Kenichi; Omori, Daisuke; Sano, Tetsuya; Suganuma, Eisuke; Takahashi, Tsutomu; Takatsuki, Shinichi; Takeda, Atsuhito; Terai, Masaru; Toyono, Manatomo; Watanabe, Kenichi; Watanabe, Makoto; Yamamoto, Masaki; Yamamura, Kenichiro

2018-05-07

Few studies with sufficient statistical power have shown the association of the z score of the coronary arterial internal diameter with coronary events (CE) in patients with Kawasaki disease (KD) with coronary artery aneurysms (CAA). To clarify the association of the z score with time-dependent CE occurrence in patients with KD with CAA. This multicenter, collaborative retrospective cohort study of 44 participating institutions included 1006 patients with KD younger than 19 years who received a coronary angiography between 1992 and 2011. The time-dependent occurrence of CE, including thrombosis, stenosis, obstruction, acute ischemic events, and coronary interventions, was analyzed for small (z score, <5), medium (z score, ≥5 to <10; actual internal diameter, <8 mm), and large (z score, ≥10 or ≥8 mm) CAA by the Kaplan-Meier method. The Cox proportional hazard regression model was used to identify risk factors for CE after adjusting for age, sex, size, morphology, number of CAA, resistance to initial intravenous immunoglobulin (IVIG) therapy, and antithrombotic medications. Of 1006 patients, 714 (71%) were male, 341 (34%) received a diagnosis before age 1 year, 501 (50%) received a diagnosis between age 1 and 5 years, and 157 (16%) received a diagnosis at age 5 years or older. The 10-year event-free survival rate for CE was 100%, 94%, and 52% in men (P < .001) and 100%, 100%, and 75% in women (P < .001) for small, medium, and large CAA, respectively. The CE-free rate was 100%, 96%, and 79% in patients who were not resistant to IVIG therapy (P < .001) and 100%, 96%, and 51% in patients who were resistant to IVIG therapy (P < .001), respectively. Cox regression analysis revealed that large CAA (hazard ratio, 8.9; 95% CI, 5.1-15.4), male sex (hazard ratio, 2.8; 95% CI, 1.7-4.8), and resistance to IVIG therapy (hazard ratio, 2.2; 95% CI, 1.4-3.6) were significantly associated with CE. Classification using the internal diameter z score is useful for assessing the severity of CAA in relation to the time-dependent occurrence of CE and associated factors in patients with KD. Careful management of CE is necessary for all patients with KD with CAA, especially men and IVIG-resistant patients with a large CAA.

Development of a Probabilistic Tsunami Hazard Analysis in Japan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toshiaki Sakai; Tomoyoshi Takeda; Hiroshi Soraoka

2006-07-01

It is meaningful for tsunami assessment to evaluate phenomena beyond the design basis as well as seismic design. Because once we set the design basis tsunami height, we still have possibilities tsunami height may exceeds the determined design tsunami height due to uncertainties regarding the tsunami phenomena. Probabilistic tsunami risk assessment consists of estimating for tsunami hazard and fragility of structures and executing system analysis. In this report, we apply a method for probabilistic tsunami hazard analysis (PTHA). We introduce a logic tree approach to estimate tsunami hazard curves (relationships between tsunami height and probability of excess) and present anmore » example for Japan. Examples of tsunami hazard curves are illustrated, and uncertainty in the tsunami hazard is displayed by 5-, 16-, 50-, 84- and 95-percentile and mean hazard curves. The result of PTHA will be used for quantitative assessment of the tsunami risk for important facilities located on coastal area. Tsunami hazard curves are the reasonable input data for structures and system analysis. However the evaluation method for estimating fragility of structures and the procedure of system analysis is now being developed. (authors)« less

Advantage of the modified Lunn-McNeil technique over Kalbfleisch-Prentice technique in competing risks

NASA Astrophysics Data System (ADS)

Lukman, Iing; Ibrahim, Noor A.; Daud, Isa B.; Maarof, Fauziah; Hassan, Mohd N.

2002-03-01

Survival analysis algorithm is often applied in the data mining process. Cox regression is one of the survival analysis tools that has been used in many areas, and it can be used to analyze the failure times of aircraft crashed. Another survival analysis tool is the competing risks where we have more than one cause of failure acting simultaneously. Lunn-McNeil analyzed the competing risks in the survival model using Cox regression with censored data. The modified Lunn-McNeil technique is a simplify of the Lunn-McNeil technique. The Kalbfleisch-Prentice technique is involving fitting models separately from each type of failure, treating other failure types as censored. To compare the two techniques, (the modified Lunn-McNeil and Kalbfleisch-Prentice) a simulation study was performed. Samples with various sizes and censoring percentages were generated and fitted using both techniques. The study was conducted by comparing the inference of models, using Root Mean Square Error (RMSE), the power tests, and the Schoenfeld residual analysis. The power tests in this study were likelihood ratio test, Rao-score test, and Wald statistics. The Schoenfeld residual analysis was conducted to check the proportionality of the model through its covariates. The estimated parameters were computed for the cause-specific hazard situation. Results showed that the modified Lunn-McNeil technique was better than the Kalbfleisch-Prentice technique based on the RMSE measurement and Schoenfeld residual analysis. However, the Kalbfleisch-Prentice technique was better than the modified Lunn-McNeil technique based on power tests measurement.

A critical analysis of hazard resilience measures within sustainability assessment frameworks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matthews, Elizabeth C., E-mail: echiso1@lsu.edu; Sattler, Meredith, E-mail: msattler@lsu.edu; Friedland, Carol J., E-mail: friedland@lsu.edu

Today, numerous sustainability assessment frameworks (SAFs) exist to guide designers in achieving sustainable performance in the design of structures and communities. SAFs are beneficial in educating users and are useful tools for incorporating sustainability strategies into planning, design, and construction; however, there is currently a substantial gap in the ability of existing SAFs to incorporate hazard resistance and hazard mitigation in the broader context of sustainable design. This paper analyzes the incorporation of hazard resistant design and hazard mitigation strategies within SAFs via a multi-level analysis of eleven SAFs. The SAFs analyzed range in scale of application (i.e. building, site,more » community). Three levels of analysis are presented: (1) macro-level analysis comparing the number of measures strictly addressing resilience versus sustainability, (2) meso-level analysis of the coverage of types of hazards within SAFs (e.g. flood, fire), and (3) micro-level analysis of SAF measures connected to flood-related hazard resilience. The results demonstrate that hazard resistance and hazard mitigation do not figure prominently in the intent of SAFs and that weaknesses in resilience coverage exist that have the potential to lead to the design of structures and communities that are still highly vulnerable to the impacts of extreme events. - Highlights: • Sustainability assessment frameworks (SAFs) were analyzed for resilience coverage • Hazard resistance and mitigation do not figure prominently in the intent of SAFs • Approximately 75% of SAFs analyzed address three or fewer hazards • Lack of economic measures within SAFs could impact resilience and sustainability • Resilience measures for flood hazards are not consistently included in SAFs.« less

The Impact of Epidemiological Factors and Treatment Interventions on Survival in Patients With Signet Ring Cell Carcinoma of the Pancreas.

PubMed

Patel, Mausam; Hans, Harliv S; Pan, Kelsey; Khan, Humza; Donath, Elie; Caldera, Humberto

2018-04-18

Primary pancreatic signet ring cell carcinoma (SRCC) is a rare histologic variant of pancreatic carcinoma. A population-based analysis of pancreatic SRCC was performed to determine the predictive effects of epidemiological factors and treatment interventions on overall survival (OS) and disease-specific survival (DSS). The Surveillance, Epidemiology, and End Results registry was searched for pancreatic SRCC cases diagnosed between January 1, 1973 and December 31, 2013. Statistical analysis was performed using the Fisher exact test, χ analysis, Kaplan-Meier method, log-rank test, and Cox proportional hazards regression. The mean age among 497 patients was 66.6 years (SD, 11.9). Most patients were white (82.7%) and male (54.5%). The 1-, 2-, and 5-year OS rates were 17%, 9%, and 4%, respectively, while the corresponding 1-, 2-, and 5-year rates for DSS were 18%, 10%, and 5%, respectively. On univariable analysis; age, site, grade, stage, and treatment were predictive of OS and DSS (P<0.05). On multivariable analysis; radiation improved OS and DSS (adjusted hazard ratio [aHR], 0.592 and 0.589, respectively), pancreatectomy improved OS and DSS (aHR, 0.360 and 0.355, respectively), and combination therapy improved OS and DSS (aHR, 0.295 and 0.286, respectively). Age, site, and stage were also independent predictors of OS and DSS. Subgroup analysis demonstrated treatment to be an independent predictor of OS and DSS in localized/regional disease, in distant disease, and in patients diagnosed between 2000 and 2013. Age, site, stage, and treatment independently predict OS and DSS in pancreatic SRCC.

Comparison of escitalopram versus citalopram for the treatment of major depressive disorder in a geriatric population.

PubMed

Wu, Eric; Greenberg, Paul E; Yang, Elaine; Yu, Andrew; Erder, M Haim

2008-09-01

To compare escitalopram versus citalopram for the treatment of major depressive disorder (MDD) in geriatric patients. Administrative claims data (2003-2005) were analyzed for patients aged > or =65 years with at least one inpatient claim or two independent medical claims associated with MDD diagnosis. Patients were continuously enrolled for at least 12 months, filled at least one prescription for citalopram or escitalopram and had no second generation antidepressant use during the 6-month pre-index date. Contingency table analysis and survival analysis were used to compare outcomes between the two treatment groups. Treatment persistence, hospitalization utilization, and prescription drug, medical, and total healthcare costs were analyzed. Outcomes were compared between patients initiated on escitalopram and those initiated on citalopram both descriptively and using multivariate analysis adjusting for baseline characteristics. Among 691 geriatric patients, escitalopram-treated patients (n=459) were less likely to discontinue treatment (hazard ratio [HR]=0.83, p=0.049) or switch to another second generation antidepressant (HR=0.62, p=0.001) compared to patients treated with citalopram (n=232). Patients treated with escitalopram had a significantly lower hospitalization rate (31.2% vs. 38.8%, p=0.045) and 66% fewer hospitalization days based on negative binomial regression (p<0.001). While escitalopram patients had comparable prescription drug costs, they had lower total medical service costs (regression: $9748 vs. $19,208, p<0.001) and lower total healthcare costs (regression: $11,434 vs. $20,601, p<0.001). This study's limitations include its small sample size, short observational periods and exclusivity of indirect costs. Geriatric patients treated with escitalopram had better treatment persistence, fewer hospitalizations, and lower medical and total healthcare costs than patients treated with citalopram. Most of the cost reduction was attributable to significantly lower hospitalizations and total medical costs.

AURKA mRNA expression is an independent predictor of poor prognosis in patients with non-small cell lung cancer.

PubMed

Al-Khafaji, Ahmed S K; Marcus, Michael W; Davies, Michael P A; Risk, Janet M; Shaw, Richard J; Field, John K; Liloglou, Triantafillos

2017-06-01

Deregulation of mitotic spindle genes has been reported to contribute to the development and progression of malignant tumours. The aim of the present study was to explore the association between the expression profiles of Aurora kinases ( AURKA , AURKB and AURKC ), cytoskeleton-associated protein 5 ( CKAP5 ), discs large-associated protein 5 ( DLGAP5 ), kinesin-like protein 11 ( KIF11 ), microtubule nucleation factor ( TPX2 ), monopolar spindle 1 kinase ( TTK ), and β-tubulins ( TUBB ) and ( TUBB3 ) genes and clinicopathological characteristics in human non-small cell lung carcinoma (NSCLC). Reverse transcription-quantitative polymerase chain reaction-based RNA gene expression profiles of 132 NSCLC and 44 adjacent wild-type tissues were generated, and Cox's proportional hazard regression was used to examine associations. With the exception of AURKC , all genes exhibited increased expression in NSCLC tissues. Of the 10 genes examined, only AURKA was significantly associated with prognosis in NSCLC. Multivariate Cox's regression analysis demonstrated that AURKA mRNA expression [hazard ratio (HR), 1.81; 95% confidence interval (CI), 1.16-2.84; P=0.009], age (HR, 1.03; 95% CI, 1.00-1.06; P=0.020), pathological tumour stage 2 (HR, 2.43; 95% CI, 1.16-5.10; P=0.019) and involvement of distal nodes (pathological node stage 2) (HR, 3.14; 95% CI, 1.24-7.99; P=0.016) were independent predictors of poor prognosis in patients with NSCLC. Poor prognosis of patients with increased AURKA expression suggests that those patients may benefit from surrogate therapy with AURKA inhibitors.

African American race but not genome-wide ancestry is negatively associated with atrial fibrillation among postmenopausal women in the Women's Health Initiative.

PubMed

Perez, Marco V; Hoffmann, Thomas J; Tang, Hua; Thornton, Timothy; Stefanick, Marcia L; Larson, Joseph C; Kooperberg, Charles; Reiner, Alex P; Caan, Bette; Iribarren, Carlos; Risch, Neil

2013-09-01

Atrial fibrillation (AF) is the most common arrhythmia in women and is associated with higher rates of stroke and death. Rates of AF are lower in African American subjects compared with European Americans, suggesting European ancestry could contribute to AF risk. The Women's Health Initiative (WHI) Observational Study (OS) followed up 93,676 women since the mid 1990s for various cardiovascular outcomes including AF. Multivariate Cox hazard regression analysis was used to measure the association between African American race and incident AF. A total of 8,119 African American women from the WHI randomized clinical trials and OS were genotyped on the Affymetrix Human SNP Array 6.0. Genome-wide ancestry and previously reported single nucleotide polymorphisms associated with AF in European cohorts were tested for association with AF using multivariate logistic regression analyses. Self-reported African American race was associated with lower rates of AF (hazard ratio 0.43, 95% CI 0.32-0.60) in the OS, independent of demographic and clinical risk factors. In the genotyped cohort, there were 558 women with AF. By contrast, genome-wide European ancestry was not associated with AF. None of the single nucleotide polymorphisms previously associated with AF in European populations, including rs2200733, were associated with AF in the WHI African American cohort. African American race is significantly and inversely correlated with AF in postmenopausal women. The etiology of this association remains unclear and may be related to unidentified environmental differences. Larger studies are necessary to identify genetic determinants of AF in African Americans. © 2013.

Race, Wealth, and Solid Waste Facilities in North Carolina

PubMed Central

Norton, Jennifer M.; Wing, Steve; Lipscomb, Hester J.; Kaufman, Jay S.; Marshall, Stephen W.; Cravey, Altha J.

2007-01-01

Background Concern has been expressed in North Carolina that solid waste facilities may be disproportionately located in poor communities and in communities of color, that this represents an environmental injustice, and that solid waste facilities negatively impact the health of host communities. Objective Our goal in this study was to conduct a statewide analysis of the location of solid waste facilities in relation to community race and wealth. Methods We used census block groups to obtain racial and economic characteristics, and information on solid waste facilities was abstracted from solid waste facility permit records. We used logistic regression to compute prevalence odds ratios for 2003, and Cox regression to compute hazard ratios of facilities issued permits between 1990 and 2003. Results The adjusted prevalence odds of a solid waste facility was 2.8 times greater in block groups with ≥50% people of color compared with block groups with < 10% people of color, and 1.5 times greater in block groups with median house values < $60,000 compared with block groups with median house values ≥$100,000. Among block groups that did not have a previously permitted solid waste facility, the adjusted hazard of a new permitted facility was 2.7 times higher in block groups with ≥50% people of color compared with block groups with < 10% people of color. Conclusion Solid waste facilities present numerous public health concerns. In North Carolina solid waste facilities are disproportionately located in communities of color and low wealth. In the absence of action to promote environmental justice, the continued need for new facilities could exacerbate this environmental injustice. PMID:17805426

Ibrutinib versus previous standard of care: an adjusted comparison in patients with relapsed/refractory chronic lymphocytic leukaemia.

PubMed

Hansson, Lotta; Asklid, Anna; Diels, Joris; Eketorp-Sylvan, Sandra; Repits, Johanna; Søltoft, Frans; Jäger, Ulrich; Österborg, Anders

2017-10-01

This study explored the relative efficacy of ibrutinib versus previous standard-of-care treatments in relapsed/refractory patients with chronic lymphocytic leukaemia (CLL), using multivariate regression modelling to adjust for baseline prognostic factors. Individual patient data were collected from an observational Stockholm cohort of consecutive patients (n = 144) diagnosed with CLL between 2002 and 2013 who had received at least second-line treatment. Data were compared with results of the RESONATE clinical trial. A multivariate Cox proportional hazards regression model was used which estimated the hazard ratio (HR) of ibrutinib versus previous standard of care. The adjusted HR of ibrutinib versus the previous standard-of-care cohort was 0.15 (p < 0.0001) for progression-free survival (PFS) and 0.36 (p < 0.0001) for overall survival (OS). A similar difference was observed also when patients treated late in the period (2012-) were compared separately. Multivariate analysis showed that later line of therapy, male gender, older age and poor performance status were significant independent risk factors for worse PFS and OS. Our results suggest that PFS and OS with ibrutinib in the RESONATE study were significantly longer than with previous standard-of-care regimens used in second or later lines in routine healthcare. The approach used, which must be interpreted with caution, compares patient-level data from a clinical trial with outcomes observed in a daily clinical practice and may complement results from randomised trials or provide preliminary wider comparative information until phase 3 data exist.

Prediction of spatially explicit rainfall intensity-duration thresholds for post-fire debris-flow generation in the western United States

NASA Astrophysics Data System (ADS)

Staley, Dennis; Negri, Jacquelyn; Kean, Jason

2016-04-01

Population expansion into fire-prone steeplands has resulted in an increase in post-fire debris-flow risk in the western United States. Logistic regression methods for determining debris-flow likelihood and the calculation of empirical rainfall intensity-duration thresholds for debris-flow initiation represent two common approaches for characterizing hazard and reducing risk. Logistic regression models are currently being used to rapidly assess debris-flow hazard in response to design storms of known intensities (e.g. a 10-year recurrence interval rainstorm). Empirical rainfall intensity-duration thresholds comprise a major component of the United States Geological Survey (USGS) and the National Weather Service (NWS) debris-flow early warning system at a regional scale in southern California. However, these two modeling approaches remain independent, with each approach having limitations that do not allow for synergistic local-scale (e.g. drainage-basin scale) characterization of debris-flow hazard during intense rainfall. The current logistic regression equations consider rainfall a unique independent variable, which prevents the direct calculation of the relation between rainfall intensity and debris-flow likelihood. Regional (e.g. mountain range or physiographic province scale) rainfall intensity-duration thresholds fail to provide insight into the basin-scale variability of post-fire debris-flow hazard and require an extensive database of historical debris-flow occurrence and rainfall characteristics. Here, we present a new approach that combines traditional logistic regression and intensity-duration threshold methodologies. This method allows for local characterization of both the likelihood that a debris-flow will occur at a given rainfall intensity, the direct calculation of the rainfall rates that will result in a given likelihood, and the ability to calculate spatially explicit rainfall intensity-duration thresholds for debris-flow generation in recently burned areas. Our approach synthesizes the two methods by incorporating measured rainfall intensity into each model variable (based on measures of topographic steepness, burn severity and surface properties) within the logistic regression equation. This approach provides a more realistic representation of the relation between rainfall intensity and debris-flow likelihood, as likelihood values asymptotically approach zero when rainfall intensity approaches 0 mm/h, and increase with more intense rainfall. Model performance was evaluated by comparing predictions to several existing regional thresholds. The model, based upon training data collected in southern California, USA, has proven to accurately predict rainfall intensity-duration thresholds for other areas in the western United States not included in the original training dataset. In addition, the improved logistic regression model shows promise for emergency planning purposes and real-time, site-specific early warning. With further validation, this model may permit the prediction of spatially-explicit intensity-duration thresholds for debris-flow generation in areas where empirically derived regional thresholds do not exist. This improvement would permit the expansion of the early-warning system into other regions susceptible to post-fire debris flow.

REGRESSION MODELS FOR COHORT MORTALITY STUDIES

EPA Science Inventory

Cohort studies evaluate suspect health hazards from occupational or environmental exposures by recording tile facts and causes of deaths in the exposed group as they occur over an extended time period. his article reviews several methods for analyzing cohort: mortality data and s...

On comparison of net survival curves.

PubMed

Pavlič, Klemen; Perme, Maja Pohar

2017-05-02

Relative survival analysis is a subfield of survival analysis where competing risks data are observed, but the causes of death are unknown. A first step in the analysis of such data is usually the estimation of a net survival curve, possibly followed by regression modelling. Recently, a log-rank type test for comparison of net survival curves has been introduced and the goal of this paper is to explore its properties and put this methodological advance into the context of the field. We build on the association between the log-rank test and the univariate or stratified Cox model and show the analogy in the relative survival setting. We study the properties of the methods using both the theoretical arguments as well as simulations. We provide an R function to enable practical usage of the log-rank type test. Both the log-rank type test and its model alternatives perform satisfactory under the null, even if the correlation between their p-values is rather low, implying that both approaches cannot be used simultaneously. The stratified version has a higher power in case of non-homogeneous hazards, but also carries a different interpretation. The log-rank type test and its stratified version can be interpreted in the same way as the results of an analogous semi-parametric additive regression model despite the fact that no direct theoretical link can be established between the test statistics.

Recurrence risk model for esophageal cancer after radical surgery.

PubMed

Lu, Jincheng; Tao, Hua; Song, Dan; Chen, Cheng

2013-10-01

The aim of the present study was to construct a risk assessment model which was tested by disease-free survival (DFS) of esophageal cancer after radical surgery. A total of 164 consecutive esophageal cancer patients who had undergone radical surgery between January 2005 and December 2006 were retrospectively analyzed. The cutpoint of value at risk (VaR) was inferred by stem-and-leaf plot, as well as by independent-samples t-test for recurrence-free time, further confirmed by crosstab chi-square test, univariate analysis and Cox regression analysis for DFS. The cutpoint of VaR was 0.3 on the basis of our model. The rate of recurrence was 30.3% (30/99) and 52.3% (34/65) in VaR <0.3 and VaR ≥0.3 (chi-square test, (χ) (2) =7.984, P=0.005), respectively. The 1-, 3-, and 5-year DFS of esophageal cancer after radical surgery was 70.4%, 48.7%, and 45.3%, respectively in VaR ≥0.3, whereas 91.5%, 75.8%, and 67.3%, respectively in VaR <0.3 (Log-rank test, (χ) (2) =9.59, P=0.0020), and further confirmed by Cox regression analysis [hazard ratio =2.10, 95% confidence interval (CI): 1.2649-3.4751; P=0.0041]. The model could be applied for integrated assessment of recurrence risk after radical surgery for esophageal cancer.

Recurrence risk model for esophageal cancer after radical surgery

PubMed Central

Tao, Hua; Song, Dan; Chen, Cheng

2013-01-01

Objective The aim of the present study was to construct a risk assessment model which was tested by disease-free survival (DFS) of esophageal cancer after radical surgery. Methods A total of 164 consecutive esophageal cancer patients who had undergone radical surgery between January 2005 and December 2006 were retrospectively analyzed. The cutpoint of value at risk (VaR) was inferred by stem-and-leaf plot, as well as by independent-samples t-test for recurrence-free time, further confirmed by crosstab chi-square test, univariate analysis and Cox regression analysis for DFS. Results The cutpoint of VaR was 0.3 on the basis of our model. The rate of recurrence was 30.3% (30/99) and 52.3% (34/65) in VaR <0.3 and VaR ≥0.3 (chi-square test, χ2 =7.984, P=0.005), respectively. The 1-, 3-, and 5-year DFS of esophageal cancer after radical surgery was 70.4%, 48.7%, and 45.3%, respectively in VaR ≥0.3, whereas 91.5%, 75.8%, and 67.3%, respectively in VaR <0.3 (Log-rank test, χ2 =9.59, P=0.0020), and further confirmed by Cox regression analysis [hazard ratio =2.10, 95% confidence interval (CI): 1.2649-3.4751; P=0.0041]. Conclusions The model could be applied for integrated assessment of recurrence risk after radical surgery for esophageal cancer. PMID:24255579

K Basin Hazard Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

PECH, S.H.

This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Final Safety Analysis Report. This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report.

Earthquake induced liquefaction hazard, probability and risk assessment in the city of Kolkata, India: its historical perspective and deterministic scenario

NASA Astrophysics Data System (ADS)

Nath, Sankar Kumar; Srivastava, Nishtha; Ghatak, Chitralekha; Adhikari, Manik Das; Ghosh, Ambarish; Sinha Ray, S. P.

2018-01-01

Liquefaction-induced ground failure is one amongst the leading causes of infrastructure damage due to the impact of large earthquakes in unconsolidated, non-cohesive, water saturated alluvial terrains. The city of Kolkata is located on the potentially liquefiable alluvial fan deposits of Ganga-Bramhaputra-Meghna Delta system with subsurface litho-stratigraphic sequence comprising of varying percentages of clay, cohesionless silt, sand, and gravel interbedded with decomposed wood and peat. Additionally, the region has moderately shallow groundwater condition especially in the post-monsoon seasons. In view of burgeoning population, there had been unplanned expansion of settlements in the hazardous geological, geomorphological, and hydrological conditions exposing the city to severe liquefaction hazard. The 1897 Shillong and 1934 Bihar-Nepal earthquakes both of M w 8.1 reportedly induced Modified Mercalli Intensity of IV-V and VI-VII respectively in the city reportedly triggering widespread to sporadic liquefaction condition with surface manifestation of sand boils, lateral spreading, ground subsidence, etc., thus posing a strong case for liquefaction potential analysis in the terrain. With the motivation of assessing seismic hazard, vulnerability, and risk of the city of Kolkata through a consorted federal funding stipulated for all the metros and upstart urban centers in India located in BIS seismic zones III, IV, and V with population more than one million, an attempt has been made here to understand the liquefaction susceptibility condition of Kolkata under the impact of earthquake loading employing modern multivariate techniques and also to predict deterministic liquefaction scenario of the city in the event of a probabilistic seismic hazard condition with 10% probability of exceedance in 50 years and a return period of 475 years. We conducted in-depth geophysical and geotechnical investigations in the city encompassing 435 km2 area. The stochastically synthesized bedrock ground motion for both the 1897 and 1934 earthquakes on non-linear analysis of local site conditions through DEEPSOIL Geotechnical analysis package present surface level peak ground acceleration of the order of 0.05-0.14 g for the 1934 Bihar-Nepal earthquake while for the 1897 Shillong earthquake it is found to be in the range of 0.03-0.11 g. The factor of safety (FOS) against liquefaction, the probability of liquefaction ( P L), the liquefaction potential index (LPI), and the liquefaction risk index are estimated under the influence of these two earthquakes wherein the city is classified into severe (LPI > 15), high (5 < LPI ≤ 15), moderate (0 < LPI ≤ 5), and non-liquefiable (LPI = 0) susceptibility zones. While the 1934 Bihar-Nepal earthquake induced moderate to severe liquefaction hazard condition in the city in mostly the deltaic plain and interdistributary marsh geomorphologic units with 13.5% sites exhibiting moderate hazard with a median LPI of 1.8, 8.5% sites depicting high with a median LPI of 9.1 and 4% sites with a median LPI of 18.9 exhibiting severe hazard condition, 1897 Shillong earthquake induced mostly non-liquefaction condition with very few sites depicting moderate and high liquefaction hazard. A conservative liquefaction hazard scenario of the city on the other hand estimated through deterministic approach for 10% probability of exceedance in 50 years predicts a high hazard zone in the 3.5-19 m depth region with FOS < 1 and P L > 65% comprising of coarse-grained sediments of sand, silty sand, and clayey silty sand in mostly the deltaic plain geomorphologic unit with 39.1% sites depicting severe liquefaction hazard with a median LPI of 28.3. A non-linear regression analysis on both the historical and deterministic liquefaction scenarios in P L versus LPI domain with ± 1 standard deviation confidence bound generated a cubic polynomial relationship between the two liquefaction hazard proxies. This study considered a bench mark for other cities in the country and elsewhere forms an integral part of the mega-seismic microzonation endeavors undertaken in all the earthquake-prone counties in the world.

Prediction of Low Birth Weight Delivery by Maternal Status and Its Validation: Decision Curve Analysis.

PubMed

Rejali, Mehri; Mansourian, Marjan; Babaei, Zohre; Eshrati, Babak

2017-01-01

In this study, we evaluated assessed elements connected with low birth weight (LBW) and used decision curve analysis (DCA) to define a scale to anticipate the probability of having a LBW newborn child. This hospital-based case-control study was led in Arak Hospital in Iran. The study included 470 mothers with LBW neonate and 470 mothers with natural neonates. Information were gathered by meeting moms utilizing preplanned organized questionnaire and from hospital records. The estimated probabilities of detecting LBW were calculated using the logistic regression and DCA to quantify the clinical consequences and its validation. Factors significantly associated with LBW were premature membrane rupture (odds ratio [OR] = 3.18 [1.882-5.384]), former LBW infants (OR = 2.99 [1.510-5.932]), premature pain (OR = 2.70 [1.659-4.415]), hypertension in pregnancy (OR = 2.39 [1.429-4.019]), last trimester of pregnancy bleeding (OR = 2.58 [1.018-6.583]), mother age >30 (OR = 2.17 [1.350-3.498]). However, with DCA, the prediction model made on these 15 variables has a net benefit (NB) of 0.3110 is best predictive with the highest NB. NB has simple clinical interpretation and utilizing the model is what might as well be called a procedure that distinguished what might as well be called 31.1 LBW per 100 cases with no superfluous recognize. It is conceivable to foresee LBW utilizing a prediction model show in light of noteworthy hazard components connected with LBW. The majority of the hazard elements for LBW are preventable, and moms can be alluded amid early pregnancy to a middle which is furnished with facilities for administration of high hazard pregnancy and LBW infant.

An Update on Mortality in the U.S. Astronaut Corps: 1959-2009

NASA Technical Reports Server (NTRS)

Amirian, E.; Clark, April; Halm, Melissa; Hartnett, Heather

2009-01-01

Although it has now been over 50 years since mankind first ventured into space, the long-term health impacts of human space flight remain largely unknown. Identifying factors that affect survival and prognosis among those who participate in space flight is vitally important, as the era of commercial space flight approaches and NASA prepares for missions to Mars. The Longitudinal Study of Astronaut Health is a prospective study designed to examine trends in astronaut morbidity and mortality. The purpose of this analysis was to describe and explore predictors of overall and cause-specific mortality among individuals selected for the U.S. astronaut corps. All U.S. astronauts (n=321), regardless of flight status, were included in this analysis. Death certificate searches were conducted to ascertain vital status and cause of death through April 2009. Data were collected from medical records and lifestyle questionnaires. Multivariable Cox regression modeling was used to calculate the mortality hazard associated with embarking on space flight, adjusted for sex, race, and age at selection. Between 1959 and 2009, there were 39 (12.1%) deaths. Of these deaths, 18 (42.2%) were due to occupational accidents; 7 (17.9%) were due to other accidents; 6 (15.4%) were attributable to cancer; 6 (15.4%) resulted from cardiovascular/circulatory diseases; and 2 (5.1%) were from other causes. Participation in space flight did not significantly increase mortality hazard over time (adjusted hazard ratio=0.57; 95% confidence interval=0.26-1.26. Because our results are based on a small sample size, future research that includes payload specialists, other space flight participants, and international crew members is warranted to maximize statistical power.

Predictors of liver-related death among people who inject drugs in Vancouver, Canada: a 15-year prospective cohort study

PubMed Central

Hayashi, Kanna; Milloy, Michael-John; Wood, Evan; Dong, Huiru; Montaner, Julio SG; Kerr, Thomas

2014-01-01

Introduction While HIV/AIDS remains an important cause of death among people who inject drugs (PWID), the potential mortality burden attributable to hepatitis C virus (HCV) infection among this population is of increasing concern. Therefore, we sought to identify trends in and predictors of liver-related mortality among PWID. Methods Data were derived from prospective cohorts of PWID in Vancouver, Canada, between 1996 and 2011. Cohort data were linked to the provincial vital statistics database to ascertain mortality rates and causes of death. Multivariate Cox proportional hazards regression was used to examine the relationship between HCV infection and time to liver-related death. A sub-analysis examined the effect of HIV/HCV co-infection. Results and discussion In total, 2,279 PWID participated in this study, with 1,921 (84.3%) having seroconverted to anti-HCV prior to baseline assessments and 124 (5.4%) during follow-up. The liver-related mortality rate was 2.1 (95% confidence interval [CI]: 1.5–3.0) deaths per 1,000 person-years and was stable over time. In multivariate analyses, HCV seropositivity was not significantly associated with liver-related mortality (adjusted relative hazard [ARH]: 0.45; 95% CI: 0.15–1.37), but HIV seropositivity was (ARH: 2.67; 95% CI: 1.27–5.63). In sub-analysis, HIV/HCV co-infection had a 2.53 (95% CI: 1.18–5.46) times hazard of liver-related death compared with HCV mono-infection. Conclusions In this study, HCV seropositivity did not predict liver-related mortality while HIV seropositivity did. The findings highlight the critical role of HIV mono- and co-infection rather than HCV infection in contributing to liver-related mortality among PWID in this setting. PMID:25391765

Loss to Follow-Up in a Community Clinic in South Africa – Roles of Gender, Pregnancy and CD4 count

PubMed Central

Wang, Bingxia; Losina, Elena; Stark, Ruth; Munro, Alison; Walensky, Rochelle P.; Wilke, Marisa; Martin, Des; Lu, Zhigang; Freedberg, Kenneth A.; Wood, Robin

2013-01-01

Background Faith-based organizations have expanded access to antiretroviral therapy (ART) in community clinics across South Africa. Loss to follow-up (LTFU), however, limits both the potential individual and population treatment benefits and is an obstacle to optimal care. Objective To identify patient characteristics associated with LTFU six months after starting ART in patients in a large South African community clinic. Methods Patients initiating ART between April 2004 and October 2006 in one Catholic Relief Services HIV treatment clinic who had at least one follow-up visit were included in the analysis. Standardized instruments were used for data collection. Routine monitoring was performed every 6 months following ART initiation. Rates of LTFU over time were estimated by the Kaplan-Meier method. The log-rank test was used to examine the impact of age, baseline CD4 count, HIV RNA, gender and pregnancy status for women on LTFU. Cox proportional hazard regression was performed to analyze hazard ratios for LTFU. Results Data from 925 patients (age > 14 years), median age 36 years, 70% female (16% pregnant) were included in the analysis. Fifty one patients (6%) were lost to follow-up six months after ART initiation. When stratified by baseline CD4 count, gender and pregnancy status, pregnant women with lower baseline CD4 count (≤200 /μl) had 6.06 times (95% CI: 2.20 – 16.71) the hazard of LTFU compared to men. Conclusions HIV-infected pregnant women initiating ART are significantly more likely to be lost to follow-up in a community clinic in South Africa. Interventions to successfully retain pregnant women in care are urgently needed. PMID:21786730

A 10-Year Retrospective Review of a Nonrandomized Cohort of 458 Patients Undergoing Radical Radiotherapy or Cystectomy in Yorkshire, UK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Munro, Nicholas P., E-mail: nic@munron.plus.co; Sundaram, Subramnian K.; Weston, Philip

2010-05-01

Purpose: We have previously reported on the mortality, morbidity, and 5-year survival of 458 patients who underwent radical radiotherapy or surgery for invasive bladder cancer in Yorkshire from 1993 to 1996. We aim to present the 10-year outcomes of these patients and to reassess factors predicting survival. Methods and Materials: The Northern and Yorkshire Cancer Registry identified 458 patients whose cases were subjected to Kaplan-Meier all-cause survival analyses, and a retrospective casenote analysis was undertaken on 398 (87%) for univariate and multivariate Cox proportional hazards modeling. Additional proportional hazards regression modeling was used to assess the statistical significance of variablesmore » on overall survival. Results: The ratio of radiotherapy to cystectomy was 3:1. There was no significant difference in overall 10-year survival between those who underwent radiotherapy (22%) and radical cystectomy (24%). Univariate analyses suggested that female sex, performance status, hydronephrosis and clinical T stage, were associated with an inferior outcome at 10 years. Patient age, tumor grade, treatment delay, and caseload factors were not significant. Multivariate analysis models were created for 0-2 and 2-10 years after treatment. There were no significant differences in treatment for 0-2 years; however, after 2 years follow-up there was some evidence of increased survival for patients receiving surgery compared with radiotherapy (hazard ratio 0.66, 95% confidence interval: 0.44-1.01, p = 0.06). Conclusions: a 10-year minimum follow-up has rarely been reported after radical treatment for invasive bladder cancer. At 10 years, there was no statistical difference in all-cause survival between surgery and radiotherapy treatment modalities.« less

Albumin and C-reactive protein have prognostic significance in patients with community-acquired pneumonia.

PubMed

Lee, Jae Hyuk; Kim, Jooyeong; Kim, Kyuseok; Jo, You Hwan; Rhee, JoongEui; Kim, Tae Youn; Na, Sang Hoon; Hwang, Seung Sik

2011-06-01

This study aims to determine the association of commonly used biochemical markers, such as albumin and C-reactive protein (CRP), with mortality and the prognostic performance of these markers combined with the pneumonia severity index (PSI) for mortality and adverse outcomes in patients with community-acquired pneumonia (CAP). The data were gathered prospectively for patients hospitalized with CAP via the emergency department. Laboratory values, including CRP and albumin, clinical variables, and the PSI were measured. Primary outcomes were 28-day mortality and survival times. Secondary outcome was admission to the intensive care unit, vasopressor use, or the need for mechanical ventilation during the hospital stay. A total of 424 patients were included. The 28-day mortality was 13.7%. C-reactive protein and albumin were significantly different between survivors and nonsurvivors. In logistic regression analysis, CRP and albumin were independently associated with 28-day mortality (P < .05). Receiver operating characteristic curves showed improved mortality prediction by adding CRP or albumin to the PSI scale. The Cox proportional hazards analysis showed that high serum albumin (≥3.3 mg/dL) had a hazard ratio of 0.5 (95% confidence interval, 0.3-0.9), and high CRP (≥14.3 mg/dL) had a hazard ratio of 2.0 (95% confidence interval, 1.1-3.4). For predicting secondary outcome, adding albumin to PSI increased areas under the curve significantly, but CRP did not. Albumin and CRP were associated with 28-day mortality in hospitalized patients with CAP, and these markers increased prognostic performance when combined with the PSI scale. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

Prognostic implications of mutation-specific QTc standard deviation in congenital long QT syndrome.

PubMed

Mathias, Andrew; Moss, Arthur J; Lopes, Coeli M; Barsheshet, Alon; McNitt, Scott; Zareba, Wojciech; Robinson, Jennifer L; Locati, Emanuela H; Ackerman, Michael J; Benhorin, Jesaia; Kaufman, Elizabeth S; Platonov, Pyotr G; Qi, Ming; Shimizu, Wataru; Towbin, Jeffrey A; Michael Vincent, G; Wilde, Arthur A M; Zhang, Li; Goldenberg, Ilan

2013-05-01

Individual corrected QT interval (QTc) may vary widely among carriers of the same long QT syndrome (LQTS) mutation. Currently, neither the mechanism nor the implications of this variable penetrance are well understood. To hypothesize that the assessment of QTc variance in patients with congenital LQTS who carry the same mutation provides incremental prognostic information on the patient-specific QTc. The study population comprised 1206 patients with LQTS with 95 different mutations and ≥ 5 individuals who carry the same mutation. Multivariate Cox proportional hazards regression analysis was used to assess the effect of mutation-specific standard deviation of QTc (QTcSD) on the risk of cardiac events (comprising syncope, aborted cardiac arrest, and sudden cardiac death) from birth through age 40 years in the total population and by genotype. Assessment of mutation-specific QTcSD showed large differences among carriers of the same mutations (median QTcSD 45 ms). Multivariate analysis showed that each 20 ms increment in QTcSD was associated with a significant 33% (P = .002) increase in the risk of cardiac events after adjustment for the patient-specific QTc duration and the family effect on QTc. The risk associated with QTcSD was pronounced among patients with long QT syndrome type 1 (hazard ratio 1.55 per 20 ms increment; P<.001), whereas among patients with long QT syndrome type 2, the risk associated with QTcSD was not statistically significant (hazard ratio 0.99; P = .95; P value for QTcSD-by-genotype interaction = .002). Our findings suggest that mutations with a wider variation in QTc duration are associated with increased risk of cardiac events. These findings appear to be genotype-specific, with a pronounced effect among patients with the long QT syndrome type 1 genotype. Copyright © 2013. Published by Elsevier Inc.

Obesity paradox in group 1 pulmonary hypertension: analysis of the NIH-Pulmonary Hypertension registry

PubMed Central

Mazimba, S; Holland, E; Nagarajan, V; Mihalek, AD; Kennedy, JLW; Bilchick, KC

2017-01-01

Background The ‘obesity paradox’ refers to the fact that obese patients have better outcomes than normal weight patients. This has been observed in multiple cardiovascular conditions, but evidence for obesity paradox in pulmonary hypertension (PH) remains sparse. Methods We categorized 267 patients from the National Institute of Health-PH registry into five groups based on body mass index (BMI): underweight, normal weight, overweight, obese and morbidly obese. Mortality was compared in BMI groups using the X2 statistic. Five-year probability of death using the PH connection (PHC) risk equation was calculated, and the model was compared with BMI groups using Cox proportional hazards regression and Kaplan-Meier (KM) survival curves. Results Patients had a median age of 39 years (interquartile range 30–50 years), a median BMI of 23.4 kg m −2 (21.0–26.8 kg m−2) and an overall mortality at 5 years of 50.2%. We found a U-shaped relationship between survival and 1-year mortality with the best 1-year survival in overweight patients. KM curves showed the best survival in the overweight, followed by obese and morbidly obese patients, and the worst survival in normal weight and underweight patients (log-rank P = 0.0008). In a Cox proportional hazards analysis, increasing BMI was a highly significant predictor of improved survival even after adjustment for the PHC risk equation with a hazard ratio for death of 0.921 per kg m−2 (95% confidence interval: 0.886–0.954) (P < 0.0001). Conclusion We observed that the best survival was in the overweight patients, making this more of an ‘overweight paradox’ than an ‘obesity paradox’. This has implications for risk stratification and prognosis in group 1 PH patients. PMID:28209971

A Concept–Wide Association Study of Clinical Notes to Discover New Predictors of Kidney Failure

PubMed Central

Betensky, Rebecca A.; Wright, Adam; Curhan, Gary C.; Bates, David W.; Waikar, Sushrut S.

2016-01-01

Background and objectives Identifying predictors of kidney disease progression is critical toward the development of strategies to prevent kidney failure. Clinical notes provide a unique opportunity for big data approaches to identify novel risk factors for disease. Design, setting, participants, & measurements We used natural language processing tools to extract concepts from the preceding year’s clinical notes among patients newly referred to a tertiary care center’s outpatient nephrology clinics and retrospectively evaluated these concepts as predictors for the subsequent development of ESRD using proportional subdistribution hazards (competing risk) regression. The primary outcome was time to ESRD, accounting for a competing risk of death. We identified predictors from univariate and multivariate (adjusting for Tangri linear predictor) models using a 5% threshold for false discovery rate (q value <0.05). We included all patients seen by an adult outpatient nephrologist between January 1, 2004 and June 18, 2014 and excluded patients seen only by transplant nephrology, with preexisting ESRD, with fewer than five clinical notes, with no follow-up, or with no baseline creatinine values. Results Among the 4013 patients selected in the final study cohort, we identified 960 concepts in the unadjusted analysis and 885 concepts in the adjusted analysis. Novel predictors identified included high–dose ascorbic acid (adjusted hazard ratio, 5.48; 95% confidence interval, 2.80 to 10.70; q<0.001) and fast food (adjusted hazard ratio, 4.34; 95% confidence interval, 2.55 to 7.40; q<0.001). Conclusions Novel predictors of human disease may be identified using an unbiased approach to analyze text from the electronic health record. PMID:27927892

Prediction of Low Birth Weight Delivery by Maternal Status and Its Validation: Decision Curve Analysis

PubMed Central

Rejali, Mehri; Mansourian, Marjan; Babaei, Zohre; Eshrati, Babak

2017-01-01

Background: In this study, we evaluated assessed elements connected with low birth weight (LBW) and used decision curve analysis (DCA) to define a scale to anticipate the probability of having a LBW newborn child. Methods: This hospital-based case–control study was led in Arak Hospital in Iran. The study included 470 mothers with LBW neonate and 470 mothers with natural neonates. Information were gathered by meeting moms utilizing preplanned organized questionnaire and from hospital records. The estimated probabilities of detecting LBW were calculated using the logistic regression and DCA to quantify the clinical consequences and its validation. Results: Factors significantly associated with LBW were premature membrane rupture (odds ratio [OR] = 3.18 [1.882–5.384]), former LBW infants (OR = 2.99 [1.510–5.932]), premature pain (OR = 2.70 [1.659–4.415]), hypertension in pregnancy (OR = 2.39 [1.429–4.019]), last trimester of pregnancy bleeding (OR = 2.58 [1.018–6.583]), mother age >30 (OR = 2.17 [1.350–3.498]). However, with DCA, the prediction model made on these 15 variables has a net benefit (NB) of 0.3110 is best predictive with the highest NB. NB has simple clinical interpretation and utilizing the model is what might as well be called a procedure that distinguished what might as well be called 31.1 LBW per 100 cases with no superfluous recognize. Conclusions: It is conceivable to foresee LBW utilizing a prediction model show in light of noteworthy hazard components connected with LBW. The majority of the hazard elements for LBW are preventable, and moms can be alluded amid early pregnancy to a middle which is furnished with facilities for administration of high hazard pregnancy and LBW infant. PMID:28928911

Physically and psychologically hazardous jobs and mental health in Thailand

PubMed Central

Yiengprugsawan, Vasoontara; Strazdins, Lyndall; Lim, Lynette L.-Y.; Kelly, Matthew; Seubsman, Sam-ang; Sleigh, Adrian C.

2015-01-01

This paper investigates associations between hazardous jobs, mental health and wellbeing among Thai adults. In 2005, 87 134 distance-learning students from Sukhothai Thammathirat Open University completed a self-administered questionnaire; at the 2009 follow-up 60 569 again participated. Job characteristics were reported in 2005, psychological distress and life satisfaction were reported in both 2005 and 2009. We derived two composite variables grading psychologically and physically hazardous jobs and reported adjusted odds ratios (AOR) from multivariate logistic regressions. Analyses focused on cohort members in paid work: the total was 62 332 at 2005 baseline and 41 671 at 2009 follow-up. Cross-sectional AORs linking psychologically hazardous jobs to psychological distress ranged from 1.52 (one hazard) to 4.48 (four hazards) for males and a corresponding 1.34–3.76 for females. Similarly AORs for physically hazardous jobs were 1.75 (one hazard) to 2.76 (four or more hazards) for males and 1.70–3.19 for females. A similar magnitude of associations was found between psychologically adverse jobs and low life satisfaction (AORs of 1.34–4.34 among males and 1.18–3.63 among females). Longitudinal analyses confirm these cross-sectional relationships. Thus, significant dose–response associations were found linking hazardous job exposures in 2005 to mental health and wellbeing in 2009. The health impacts of psychologically and physically hazardous jobs in developed, Western countries are equally evident in transitioning Southeast Asian countries such as Thailand. Regulation and monitoring of work conditions will become increasingly important to the health and wellbeing of the Thai workforce. PMID:24218225

Reduced COPD Exacerbation Risk Correlates With Improved FEV1: A Meta-Regression Analysis.

PubMed

Zider, Alexander D; Wang, Xiaoyan; Buhr, Russell G; Sirichana, Worawan; Barjaktarevic, Igor Z; Cooper, Christopher B

2017-09-01

The mechanism by which various classes of medication reduce COPD exacerbation risk remains unknown. We hypothesized a correlation between reduced exacerbation risk and improvement in airway patency as measured according to FEV 1 . By systematic review, COPD trials were identified that reported therapeutic changes in predose FEV 1 (dFEV 1 ) and occurrence of moderate to severe exacerbations. Using meta-regression analysis, a model was generated with dFEV 1 as the moderator variable and the absolute difference in exacerbation rate (RD), ratio of exacerbation rates (RRs), or hazard ratio (HR) as dependent variables. The analysis of RD and RR included 119,227 patients, and the HR analysis included 73,475 patients. For every 100-mL change in predose FEV 1 , the HR decreased by 21% (95% CI, 17-26; P < .001; R 2  = 0.85) and the absolute exacerbation rate decreased by 0.06 per patient per year (95% CI, 0.02-0.11; P = .009; R 2  = 0.05), which corresponded to an RR of 0.86 (95% CI, 0.81-0.91; P < .001; R 2  = 0.20). The relationship with exacerbation risk remained statistically significant across multiple subgroup analyses. A significant correlation between increased FEV 1 and lower COPD exacerbation risk suggests that airway patency is an important mechanism responsible for this effect. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

Association between atherogenic dyslipidemia and recurrent stroke risk in patients with different subtypes of ischemic stroke.

PubMed

Zhao, Lu; Wang, Ruihao; Song, Bo; Tan, Song; Gao, Yuan; Fang, Hui; Lu, Jie; Xu, Yuming

2015-07-01

The association between atherogenic dyslipidemia and stroke recurrence remains unclear, and may be influenced by different subtypes of ischemic stroke. We aimed to investigate whether atherogenic dyslipidemia contributed to stroke recurrence in ischemic stroke patients and in those with certain subtypes of ischemic stroke. We conducted a prospective hospital-based study enrolling patients with acute ischemic stroke. Atherogenic dyslipidemia was defined as high-density lipoprotein cholesterol <40 mg/dl and triglycerides ≥200 mg/dl. Ischemic stroke subtypes were classified according to the Trial of Org 10172 in Acute Stroke Treatment criteria. The patients were followed up at 3, 6, 12 and 24 months after stroke onset. The association between atherogenic dyslipidemia and stroke recurrence was analyzed by using multivariable Cox regression model. In the 510 ischemic stroke patients, 64 patients (12·5%) had atherogenic dyslipidemia, and 66 patients (12·9%) experienced stroke recurrence events within 24 months. Kaplan-Meier analysis revealed that stroke recurrence rate was significantly higher in patients with atherogenic dyslipidemia than those without in all the stroke patients (20·3% vs. 11·9%; P = 0·048), and more evident in those of large-artery atherosclerosis subtype (31·0% vs. 14·1%; P = 0·014), but not in the other subtypes. Multivariable Cox regression analysis revealed that atherogenic dyslipidemia was associated with higher stroke recurrence risk among stroke patients of large-artery atherosclerosis subtype (hazard ratio, 2·79; 95% confidence interval, 1·24-6·28), but not significant in all the stroke patients (hazard ratio, 1·69; 95% confidence interval, 0·85-3·37). Atherogenic dyslipidemia is associated with higher risk of stroke recurrence in ischemic stroke patients. Such association might be more pronounced in large-artery atherosclerosis subtype and needs further investigation to establish such relationship. © 2015 World Stroke Organization.

Effect of Pathologic Tumor Response and Nodal Status on Survival in the Medical Research Council Adjuvant Gastric Infusional Chemotherapy Trial

PubMed Central

Smyth, Elizabeth C.; Fassan, Matteo; Cunningham, David; Allum, William H.; Okines, Alicia F.C.; Lampis, Andrea; Hahne, Jens C.; Rugge, Massimo; Peckitt, Clare; Nankivell, Matthew; Langley, Ruth; Ghidini, Michele; Braconi, Chiara; Wotherspoon, Andrew; Grabsch, Heike I.

2016-01-01

Purpose The Medical Research Council Adjuvant Gastric Infusional Chemotherapy (MAGIC) trial established perioperative epirubicin, cisplatin, and fluorouracil chemotherapy as a standard of care for patients with resectable esophagogastric cancer. However, identification of patients at risk for relapse remains challenging. We evaluated whether pathologic response and lymph node status after neoadjuvant chemotherapy are prognostic in patients treated in the MAGIC trial. Materials and Methods Pathologic regression was assessed in resection specimens by two independent pathologists using the Mandard tumor regression grading system (TRG). Differences in overall survival (OS) according to TRG were assessed using the Kaplan-Meier method and compared using the log-rank test. Univariate and multivariate analyses using the Cox proportional hazards method established the relationships among TRG, clinical-pathologic variables, and OS. Results Three hundred thirty resection specimens were analyzed. In chemotherapy-treated patients with a TRG of 1 or 2, median OS was not reached, whereas for patients with a TRG of 3, 4, or 5, median OS was 20.47 months. On univariate analysis, high TRG and lymph node metastases were negatively related to survival (Mandard TRG 3, 4, or 5: hazard ratio [HR], 1.94; 95% CI, 1.11 to 3.39; P = .0209; lymph node metastases: HR, 3.63; 95% CI, 1.88 to 7.0; P < .001). On multivariate analysis, only lymph node status was independently predictive of OS (HR, 3.36; 95% CI, 1.70 to 6.63; P < .001). Conclusion Lymph node metastases and not pathologic response to chemotherapy was the only independent predictor of survival after chemotherapy plus resection in the MAGIC trial. Prospective evaluation of whether omitting postoperative chemotherapy and/or switching to a noncross-resistant regimen in patients with lymph node-positive disease whose tumor did not respond to preoperative epirubicin, cisplatin, and fluorouracil may be appropriate. PMID:27298411

Bio-psychosocial determinants of time lost from work following non life threatening acute orthopaedic trauma

PubMed Central

2010-01-01

Background To determine factors predicting the duration of time away from work following acute orthopaedic non life threatening trauma Methods Prospective cohort study conducted at four hospitals in Victoria, Australia. The cohort comprised 168 patients aged 18-64 years who were working prior to the injury and sustained a range of acute unintentional orthopaedic injuries resulting in hospitalization. Baseline data was obtained by survey and medical record review. Multivariate Cox proportional hazards regression analysis was used to examine the association between potential predictors and the duration of time away from work during the six month study. The study achieved 89% follow-up. Results Of the 168 participants recruited to the study, 68% returned to work during the six month study. Multivariate Cox proportional hazards regression analysis identified that blue collar work, negative pain attitudes with respect to work, high initial pain intensity, injury severity, older age, initial need for surgery, the presence of co-morbid health conditions at study entry and an orthopaedic injury to more than one region were associated with extended duration away from work following the injury. Participants in receipt of compensation who reported high social functioning at two weeks were 2.58 times more likely to have returned to work than similar participants reporting low social functioning. When only those who had returned to work were considered, the participant reported reason for return to work " to fill the day" was a significant predictor of earlier RTW [RR 2.41 (95% C.I 1.35-4.30)] whereas "financial security" and "because they felt able to" did not achieve significance. Conclusions Many injury-related and psycho social factors affect the duration of time away from work following orthopaedic injury. Some of these are potentially modifiable and may be amenable to intervention. Further consideration of the reasons provided by participants for returning to work may provide important opportunities for social marketing approaches designed to alleviate the financial and social burden associated with work disability. PMID:20051124

Network regularised Cox regression and multiplex network models to predict disease comorbidities and survival of cancer.

PubMed

Xu, Haoming; Moni, Mohammad Ali; Liò, Pietro

2015-12-01

In cancer genomics, gene expression levels provide important molecular signatures for all types of cancer, and this could be very useful for predicting the survival of cancer patients. However, the main challenge of gene expression data analysis is high dimensionality, and microarray is characterised by few number of samples with large number of genes. To overcome this problem, a variety of penalised Cox proportional hazard models have been proposed. We introduce a novel network regularised Cox proportional hazard model and a novel multiplex network model to measure the disease comorbidities and to predict survival of the cancer patient. Our methods are applied to analyse seven microarray cancer gene expression datasets: breast cancer, ovarian cancer, lung cancer, liver cancer, renal cancer and osteosarcoma. Firstly, we applied a principal component analysis to reduce the dimensionality of original gene expression data. Secondly, we applied a network regularised Cox regression model on the reduced gene expression datasets. By using normalised mutual information method and multiplex network model, we predict the comorbidities for the liver cancer based on the integration of diverse set of omics and clinical data, and we find the diseasome associations (disease-gene association) among different cancers based on the identified common significant genes. Finally, we evaluated the precision of the approach with respect to the accuracy of survival prediction using ROC curves. We report that colon cancer, liver cancer and renal cancer share the CXCL5 gene, and breast cancer, ovarian cancer and renal cancer share the CCND2 gene. Our methods are useful to predict survival of the patient and disease comorbidities more accurately and helpful for improvement of the care of patients with comorbidity. Software in Matlab and R is available on our GitHub page: https://github.com/ssnhcom/NetworkRegularisedCox.git. Copyright © 2015. Published by Elsevier Ltd.

[Study on incidence of HIV infection among heroin addicts receiving methadone maintenance treatment in Dehong prefecture, Yunnan province].

PubMed

Duan, Song; Yang, Yue-cheng; Han, Jing; Yang, Shun-sheng; Yang, Ying-bo; Long, Yu-cun; Li, Guo-qiang; Yin, Jin-song; Xiang, Li-fen; Ye, Run-hua; Gao, Jie; Tang, Ren-hai; Pang, Lin; Rou, Ke-ming; Wu, Zun-you; He, Na

2011-12-01

To determine the incidence and risk factors of HIV infection among heroin addicts receiving methadone maintenance treatment (MMT) in Dehong prefecture, Yunnan province. All heroin addicts who were HIV negative at the initiation of MMT in June 2005 and through June 2011, in Dehong prefecture were included in the cohort analysis. HIV incidence was calculated and related risk factors determined by using Cox proportional hazard regression model. A total of 3154 MMT clinic attendants were qualified for this cohort study. By June 2011, 1023 (32.4%) of them had never received any follow-up HIV testing so were thus referred as loss to follow-up. The other 2131 (67.6%) members had received at least one follow-up HIV testing and were observed for a total of 4615.86 person-years. During the period, 22 new HIV infections or seroconverters were identified, making the overall HIV incidence as 0.48/100 person-years. The HIV incidence was higher among those who were unemployed, never married, self-reported being injecting drug users (IDUs) and HCV positive at entry into the MMT program. None of those who were always negative on follow-up-urine-testing of morphine was discovered as HIV newly infected during the follow-up period. Data from multiple regression analysis under Cox proportional hazard model indicated that after controlling for confounding variables, non-IDUs at the entry point for the MMT program, were less likely to be HIV newly-infected or seroconverted than IDUs (HR = 0.29, 95%CI: 0.11 - 0.76). MMT program in Dehong prefecture was demonstrated to be fairly effective in reducing HIV transmission through drug use. Those HIV negative attendants at the MMT clinic who were IDUs or keep using drugs during the treatment, were at higher risk of HIV seroconvertion. More efforts were needed to improve the follow-up and HIV testing programs for the MMT clinic attendants.

Joint prognostic effect of obesity and chronic systemic inflammation in patients with metastatic colorectal cancer.

PubMed

Shah, Manasi S; Fogelman, David R; Raghav, Kanwal Pratap Singh; Heymach, John V; Tran, Hai T; Jiang, Zhi-Qin; Kopetz, Scott; Daniel, Carrie R

2015-09-01

Obesity is strongly linked with chronic systemic inflammation, and each has been linked with disease progression and survival in patients with colorectal cancer (CRC). The authors investigated the joint prognostic effects of obesity and circulating cytokines in patients with metastatic CRC (mCRC), an understudied patient group. In 242 chemotherapy-naive patients with mCRC, the authors measured a multiplex cytokine panel and abstracted clinicopathological features, height, and weight from medical records. Overall survival (OS) was calculated from the date of mCRC diagnosis until the date of death from any cause and evaluated by Kaplan-Meier analysis and multivariable Cox proportional hazards regression models. Cut points for cytokines were determined by restricted cubic spline regression. In multivariable models, elevated interleukin (IL)-8, IL-2 receptor alpha, and lactate dehydrogenase (LDH) emerged as significant predictors of poor OS (hazard ratio [HR] and 95% confidence interval [95% CI] for above vs below the (referent) knot point: 2.5 [95% CI, 1.7-3.7], 1.9 [95% CI, 1.3-2.7], and 2.2 [95% CI, 1.6-3.1], respectively; all P<.001). Obesity (body mass index ≥30 kg/m(2) ) was not found to be associated with OS, but appeared to modify the relationships observed with IL-8 and LDH, which were associated with a significant 4-fold and 5-fold risk of death, respectively, in obese patients compared with a 2-fold risk of death in nonobese patients (P for interaction of .06 and .04, respectively). Similar results emerged from joint effects analysis, in which obese patients with high IL-8 (or LDH) experienced the highest risk of death. Although obesity itself was not found to be independently associated with survival in patients with mCRC, the adverse prognostic significance of LDH and IL-8 was found to be enhanced in obese patients. © 2015 American Cancer Society.

Flash Flood Type Identification within Catchments in Beijing Mountainous Area

NASA Astrophysics Data System (ADS)

Nan, W.

2017-12-01

Flash flood is a common type of disaster in mountainous area, Flash flood with the feature of large flow rate, strong flushing force, destructive power, has periodically caused loss to life and destruction to infrastructure in mountainous area. Beijing as China's political, economic and cultural center, the disaster prevention and control work in Beijing mountainous area has always been concerned widely. According to the transport mechanism, sediment concentration and density, the flash flood type identification within catchment can provide basis for making the hazards prevention and mitigation policy. Taking Beijing as the study area, this paper extracted parameters related to catchment morphological and topography features respectively. By using Bayes discriminant, Logistic regression and Random forest, the catchments in Beijing mountainous area were divided into water floods process, fluvial sediment transport process and debris flows process. The results found that Logistic regression analysis showed the highest accuracy, with the overall accuracy of 88.2%. Bayes discriminant and Random forest had poor prediction effects. This study confirmed the ability of morphological and topography features to identify flash flood process. The circularity ratio, elongation ratio and roughness index can be used to explain the flash flood types effectively, and the Melton ratio and elevation relief ratio also did a good job during the identification, whereas the drainage density seemed not to be an issue at this level of detail. Based on the analysis of spatial patterns of flash flood types, fluvial sediment transport process and debris flow process were the dominant hazards, while the pure water flood process was much less. The catchments dominated by fluvial sediment transport process were mainly distributed in the Yan Mountain region, where the fault belts were relatively dense. The debris flow process prone to occur in the Taihang Mountain region thanks to the abundant coal gangues. The pure water flood process catchments were mainly distributed in the transitional mountain front.

Bio-psychosocial determinants of time lost from work following non life threatening acute orthopaedic trauma.

PubMed

Clay, Fiona J; Newstead, Stuart V; Watson, Wendy L; Ozanne-Smith, Joan; McClure, Roderick J

2010-01-05

To determine factors predicting the duration of time away from work following acute orthopaedic non life threatening trauma Prospective cohort study conducted at four hospitals in Victoria, Australia. The cohort comprised 168 patients aged 18-64 years who were working prior to the injury and sustained a range of acute unintentional orthopaedic injuries resulting in hospitalization. Baseline data was obtained by survey and medical record review. Multivariate Cox proportional hazards regression analysis was used to examine the association between potential predictors and the duration of time away from work during the six month study. The study achieved 89% follow-up. Of the 168 participants recruited to the study, 68% returned to work during the six month study. Multivariate Cox proportional hazards regression analysis identified that blue collar work, negative pain attitudes with respect to work, high initial pain intensity, injury severity, older age, initial need for surgery, the presence of co-morbid health conditions at study entry and an orthopaedic injury to more than one region were associated with extended duration away from work following the injury. Participants in receipt of compensation who reported high social functioning at two weeks were 2.58 times more likely to have returned to work than similar participants reporting low social functioning. When only those who had returned to work were considered, the participant reported reason for return to work " to fill the day" was a significant predictor of earlier RTW [RR 2.41 (95% C.I 1.35-4.30)] whereas "financial security" and "because they felt able to" did not achieve significance. Many injury-related and psycho social factors affect the duration of time away from work following orthopaedic injury. Some of these are potentially modifiable and may be amenable to intervention. Further consideration of the reasons provided by participants for returning to work may provide important opportunities for social marketing approaches designed to alleviate the financial and social burden associated with work disability.

MicroRNA let-7, T cells, and patient survival in colorectal cancer

PubMed Central

Dou, Ruoxu; Nishihara, Reiko; Cao, Yin; Hamada, Tsuyoshi; Mima, Kosuke; Masuda, Atsuhiro; Masugi, Yohei; Shi, Yan; Gu, Mancang; Li, Wanwan; da Silva, Annacarolina; Nosho, Katsuhiko; Zhang, Xuehong; Meyerhardt, Jeffrey A.; Giovannucci, Edward L.; Chan, Andrew T.; Fuchs, Charles S.; Qian, Zhi Rong; Ogino, Shuji

2016-01-01

Experimental evidence suggests that the let-7 family of noncoding RNAs suppresses adaptive immune responses, contributing to immune evasion by the tumor. We hypothesized that the amount of let-7a and let-7b expression in colorectal carcinoma might be associated with limited T-lymphocyte infiltrates in the tumor microenvironment and worse clinical outcome. Utilizing the molecular pathological epidemiology resources of 795 rectal and colon cancers in two U.S.-nationwide prospective cohort studies, we measured tumor-associated let-7a and let-7b expression levels by quantitative reverse-transcription PCR, and CD3+, CD8+, CD45RO (PTPRC)+, and FOXP3+ cell densities by tumor tissue microarray immunohistochemistry and computer-assisted image analysis. Logistic regression analysis and Cox proportional hazards regression were used to assess associations of let-7a (and let-7b) expression (quartile predictor variables) with T-cell densities (binary outcome variables) and mortality, respectively, controlling for tumor molecular features, including microsatellite instability, CpG island methylator phenotype, LINE-1 methylation, and KRAS, BRAF, and PIK3CA mutations. Compared with cases in the lowest quartile of let-7a expression, those in the highest quartile were associated with lower densities of CD3+ [multivariate odds ratio (OR), 0.40; 95% confidence interval (CI), 0.23 to 0.67; Ptrend = 0.003] and CD45RO+ cells (multivariate OR, 0.31; 95% CI, 0.17 to 0.58; Ptrend = 0.0004), and higher colorectal cancer-specific mortality (multivariate hazard ratio, 1.82; 95% CI, 1.42 to 3.13; Ptrend = 0.001). In contrast, let-7b expression was not significantly associated with T-cell density or colorectal cancer prognosis. Our data support the role of let-7a in suppressing antitumor immunity in colorectal cancer, and suggest let-7a as a potential target of immunotherapy. PMID:27737877

Predictive value of MRI-detected extramural vascular invasion in stage T3 rectal cancer patients before neoadjuvant chemoradiation.

PubMed

Sun, Yiqun; Li, Jianwen; Shen, Lijun; Wang, Xiaolin; Tong, Tong; Gu, Yajia

2018-01-01

We set out to explore the probability of MRI-detected extramural vascular invasion (mr-EMVI) before chemoradiation to predict responses to chemoradiation and survival in stage T3 rectal cancer patients. A total of 100 patients with T3 rectal cancer who underwent MRI examination and received neoadjuvant chemoradiation and surgery were enrolled. The correlation between mr-EMVI and other clinical factors were analyzed by chi-square. Logistic regression model was performed to select the potential factors influencing tumor responses to neoadjuvant chemoradiation. A Cox proportional hazards regression model was performed to explore potential predictors of survival. The positive mr-EMVI result was more likely to be present in patients with a higher T3 subgroup (T3a+b = 7.1% vs. T3c+d = 90.1%, P < 0.001) and more likely in patients with mesorectal fascia involvement than in those without MRF (65% vs. 38.8%, P = 0.034). Compared with mr-EMVI (+) patients, more mr-EMVI (-) patients showed a good response (staged ≤ ypT2N0) (odds ratio [OR], 3.020; 95% confidence interval [CI], 1.071-8.517; P = 0.037). In univariate analysis, mr-EMVI (+) (hazard ratio [HR], 5.374; 95% CI, 1.210-23.872; P = 0.027) and lower rectal cancers (HR, 3.326; 95% CI, 1.135-9.743; P = 0.028) were significantly associated with decreased disease-free survival. A positive mr-EMVI status (HR, 5.727; 95% CI, 1.286-25.594; P = 0.022) and lower rectal cancers (HR, 3.137; 95% CI, 1.127-8.729; P = 0.029) also served as prognostic factors related to decreased disease-free survival in multivariate analysis. The mr-EMVI status before chemoradiation is a significant prognostic factor and could be used for identifying T3 rectal cancer patients who might benefit from neoadjuvant chemoradiation.

ALK gene copy number gain and its clinical significance in hepatocellular carcinoma.

PubMed

Jia, Shou-Wei; Fu, Sha; Wang, Fang; Shao, Qiong; Huang, Hong-Bing; Shao, Jian-Yong

2014-01-07

To examine the status and clinical significance of anaplastic lymphoma kinase (ALK) gene alterations in hepatocellular carcinoma (HCC) patients. A total of 213 cases of HCC were examined by fluorescent in situ hybridization using dual color break-apart ALK probes for the detection of chromosomal translocation and gene copy number gain. HCC tissue microarrays were constructed, and the correlation between the ALK status and clinicopathological variables was assessed by χ(2) test or Fisher's exact test. Survival analysis was estimated using the Kaplan-Meier approach with a Log-rank test. Univariate and multivariate analyses of clinical variables were performed using the Cox proportional hazards regression model. ALK gene translocation was not observed in any of the HCC cases included in the present study. ALK gene copy number gain (ALK/CNG) (≥ 4 copies/cell) was detected in 28 (13.15%) of the 213 HCC patients. The 3-year progression-free-survival (PFS) rate for ALK/CNG-positive HCC patients was significantly poorer than ALK/CNG-negative patients (27.3% vs 42.5%, P = 0.048), especially for patients with advanced stage III/IV (0% vs 33.5%, P = 0.007), and patients with grade III disease (24.8% vs 49.9%, P = 0.023). ALK/CNG-positive HCC patients had a significantly poorer prognosis than ALK/CNG-negative patients in the subgroup that was negative for serum hepatitis B virus DNA, with significantly different 3-year overall survival rates (18.2% vs 63.6%, P = 0.021) and PFS rates (18.2% vs 46.9%, P = 0.019). Multivariate Cox proportional hazards regression analysis suggested that ALK/CNG prevalence can predict death in HCC (HR = 1.596; 95%CI: 1.008-2.526, P = 0.046). ALK/CNG, but not translocation of ALK, is present in HCC and may be an unfavorable prognostic predictor.

ALK gene copy number gain and its clinical significance in hepatocellular carcinoma

PubMed Central

Jia, Shou-Wei; Fu, Sha; Wang, Fang; Shao, Qiong; Huang, Hong-Bing; Shao, Jian-Yong

2014-01-01

AIM: To examine the status and clinical significance of anaplastic lymphoma kinase (ALK) gene alterations in hepatocellular carcinoma (HCC) patients. METHODS: A total of 213 cases of HCC were examined by fluorescent in situ hybridization using dual color break-apart ALK probes for the detection of chromosomal translocation and gene copy number gain. HCC tissue microarrays were constructed, and the correlation between the ALK status and clinicopathological variables was assessed by χ2 test or Fisher’s exact test. Survival analysis was estimated using the Kaplan-Meier approach with a Log-rank test. Univariate and multivariate analyses of clinical variables were performed using the Cox proportional hazards regression model. RESULTS: ALK gene translocation was not observed in any of the HCC cases included in the present study. ALK gene copy number gain (ALK/CNG) (≥ 4 copies/cell) was detected in 28 (13.15%) of the 213 HCC patients. The 3-year progression-free-survival (PFS) rate for ALK/CNG-positive HCC patients was significantly poorer than ALK/CNG-negative patients (27.3% vs 42.5%, P = 0.048), especially for patients with advanced stage III/IV (0% vs 33.5%, P = 0.007), and patients with grade III disease (24.8% vs 49.9%, P = 0.023). ALK/CNG-positive HCC patients had a significantly poorer prognosis than ALK/CNG-negative patients in the subgroup that was negative for serum hepatitis B virus DNA, with significantly different 3-year overall survival rates (18.2% vs 63.6%, P = 0.021) and PFS rates (18.2% vs 46.9%, P = 0.019). Multivariate Cox proportional hazards regression analysis suggested that ALK/CNG prevalence can predict death in HCC (HR = 1.596; 95%CI: 1.008-2.526, P = 0.046). CONCLUSION: ALK/CNG, but not translocation of ALK, is present in HCC and may be an unfavorable prognostic predictor. PMID:24415871

A conceptual framework for economic optimization of single hazard surveillance in livestock production chains.

PubMed

Guo, Xuezhen; Claassen, G D H; Oude Lansink, A G J M; Saatkamp, H W

2014-06-01

Economic analysis of hazard surveillance in livestock production chains is essential for surveillance organizations (such as food safety authorities) when making scientifically based decisions on optimization of resource allocation. To enable this, quantitative decision support tools are required at two levels of analysis: (1) single-hazard surveillance system and (2) surveillance portfolio. This paper addresses the first level by presenting a conceptual approach for the economic analysis of single-hazard surveillance systems. The concept includes objective and subjective aspects of single-hazard surveillance system analysis: (1) a simulation part to derive an efficient set of surveillance setups based on the technical surveillance performance parameters (TSPPs) and the corresponding surveillance costs, i.e., objective analysis, and (2) a multi-criteria decision making model to evaluate the impacts of the hazard surveillance, i.e., subjective analysis. The conceptual approach was checked for (1) conceptual validity and (2) data validity. Issues regarding the practical use of the approach, particularly the data requirement, were discussed. We concluded that the conceptual approach is scientifically credible for economic analysis of single-hazard surveillance systems and that the practicability of the approach depends on data availability. Copyright © 2014 Elsevier B.V. All rights reserved.

Body mass index and mortality in patients with type 2 diabetes mellitus: A prospective cohort study of 11,449 participants.

PubMed

Liu, Hui; Wu, Shouling; Li, Yun; Sun, Lixia; Huang, Zhe; Lin, Liming; Liu, Yan; Ji, Chunpeng; Zhao, Hualing; Li, Chunhui; Song, Lu; Cong, Hongliang

2017-02-01

To investigate the association between body-mass index and mortality in Chinese adults T2DM. 11,449 participants of Kailuan Study with T2DM were included in this prospective cohort study. All-cause mortality was calculated using Kaplan-Meier analysis. Cox proportional hazards analysis was used to estimate the association between BMI and mortality. During a mean follow-up period of 7.25±1.42years, 1254 deaths occurred. The number of deaths of the underweight, normal weight, overweight, and obese group was 23, 389, 557, and 285; the corresponding mortality was 25.0%, 13.4%, 10.3%, and 9.4%, respectively. The obese group had the lowest all-cause mortality rate (log-rank chi-square=48.430, P<0.001). After adjusting for age, sex, fasting blood glucose, smoking status, systolic blood pressure, history of hypertension, stroke, cancer and myocardial infarction, compared with the normal weight group, Multivariate Cox proportional hazard regression analysis showed that HR (95% CI) of all-cause mortality in the underweight, overweight, and obese group was 1.497 (0.962, 2.330), 0.833 (0.728, 0.952), and 0.809 (0.690, 0.949). After stratifying for age tertiles, this trend remained. In T2DM patients in north China, the risk for all-cause mortality was lower in the overweight and the obese groups than those in the normal weight and the underweight groups. Copyright © 2017 Elsevier Inc. All rights reserved.

Course of serological tests in treated subjects with chronic Trypanosoma cruzi infection: a systematic review and meta-analysis of individual participant data.

PubMed

Sguassero, Yanina; Roberts, Karen N; Harvey, Guillermina B; Comandé, Daniel; Ciapponi, Agustín; Cuesta, Cristina B; Danesi, Emmaría; Aguiar, Camila; Andrade, Ana L; Castro, Ana Mde; Lana, Marta de; Escribà, Josep M; Fabbro, Diana L; Fernandes, Cloé D; Meira, Wendell Sf; Flores-Chávez, María; Hasslocher-Moreno, Alejandro M; Jackson, Yves; Lacunza, Carlos D; Machado-de-Assis, Girley F; Maldonado, Marisel; Monje-Rumi, María M; Molina, Israel; Martín, Catalina Muñoz-San; Murcia, Laura; Castro, Cleudson Nery de; Silveira, Celeste An; Negrette, Olga Sánchez; Segovia, Manuel; Solari, Aldo; Steindel, Mário; Streiger, Mirtha L; Bilbao, Ninfa Vera de; Zulantay, Inés; Sosa-Estani, Sergio

2018-06-04

To determine the course of serological tests in subjects with chronic T. cruzi infection treated with antitrypanosomal drugs. We conducted a systematic review and meta-analysis using individual participant data. Survival analysis and Cox proportional hazards regression model with a random effect to adjust for covariates were applied. The protocol was registered at www.crd.york.ac.uk/PROSPERO (CRD42012002162). We included 27 studies (1296 subjects) conducted in eight countries. The risk of bias was low for all domains in 17 studies (63.0%). We assessed 913 subjects (149 seroreversion events, 83.7% censored data) for ELISA, 670 subjects (134 events, 80.0% censored) for IIF, and 548 subjects (99 events, 82.0% censored) for IHA. A higher probability of seroreversion was observed in subjects aged 1-19 years compared to adults at a shorter time span. The chance of seroreversion also varied according to the country where the infection might have been acquired. For instance, the pooled adjusted hazard ratio between children/adolescents and adults for IIF test was 1.54 (95% CI 0.64-3.71) and 9.37 (3.44-25.50) in some countries of South America and Brazil, respectively. The disappearance of anti-T. cruzi antibodies was demonstrated along the follow-up. An interaction between age at treatment and country setting was shown. Copyright © 2018. Published by Elsevier Ltd.

Long Term Exposure to NO2 and Diabetes Incidence in the Black Women's Health Study

PubMed Central

Coogan, Patricia F.; White, Laura F.; Yu, Jeffrey; Burnett, Richard T.; Marshall, Julian D.; Seto, Edmund; Brook, Robert D.; Palmer, Julie R.; Rosenberg, Lynn; Jerrett, Michael

2016-01-01

While laboratory studies show that air pollutants can potentiate insulin resistance, the epidemiologic evidence regarding the association of air pollution with diabetes incidence is conflicting. The purpose of the present study was to assess the association of the traffic-related nitrogen dioxide (NO2) with the incidence of diabetes in a longitudinal cohort study of African American women. We used Cox proportional hazards models to calculate hazard ratios and 95% confidence intervals (CI) for diabetes associated with exposure to NO2 among 43,003 participants in the Black Women's Health Study (BWHS). Pollutant levels at participant residential locations were estimated with 1) a land use regression model for participants living in 56 metropolitan areas, and 2) a dispersion model for participants living in 27 of the cities. From 1995-2011, 4387 cases of diabetes occurred. The hazard ratios per interquartile range of NO2 (9.7 ppb), adjusted for age, metropolitan area, education, vigorous exercise, body mass index, smoking, and diet, were 0.96 (95% CI 0.88-1.06) using the land use regression model estimates and 0.94 (95% CI 0.80, 1.10) using the dispersion model estimates. The present results do not support the hypothesis that exposure to NO2 contributes to diabetes incidence in African American women. PMID:27124624

Abdominal Circumference Versus Body Mass Index as Predictors of Lower Extremity Overuse Injury Risk.

PubMed

Nye, Nathaniel S; Kafer, Drew S; Olsen, Cara; Carnahan, David H; Crawford, Paul F

2018-02-01

Abdominal circumference (AC) is superior to body mass index (BMI) as a measure of risk for various health outcomes. Our objective was to compare AC and BMI as predictors of lower extremity overuse injury (LEOI) risk. Retrospective review of electronic medical records of 79,868 US Air Force personnel over a 7-year period (2005-2011) for incidence of new LEOI. Subjects were stratified by BMI and AC. Injury risk for BMI/AC subgroups was calculated using Kaplan-Meier curves and Cox proportional-hazards regression. Receiver operating characteristic curves with area under the curve were used to compare each model's predictive value. Cox proportional-hazards regression showed significant risk association between elevated BMI, AC, and all injury types, with hazard ratios ranging 1.230-3.415 for obese versus normal BMI and 1.665-3.893 for high-risk versus low-risk AC (P < .05 for all measures). Receiver operating characteristic curves with area under the curve showed equivalent performance between BMI and AC for predicting all injury types. However, the combined model (AC and BMI) showed improved predictive ability over either model alone for joint injury, overall LEOI, and most strongly for osteoarthritis. Although AC and BMI alone performed similarly well, a combined approach using BMI and AC together improved risk estimation for LEOI.

Association of vegetable and fruit intake with gastric cancer risk among Japanese: a pooled analysis of four cohort studies.

PubMed

Shimazu, T; Wakai, K; Tamakoshi, A; Tsuji, I; Tanaka, K; Matsuo, K; Nagata, C; Mizoue, T; Inoue, M; Tsugane, S; Sasazuki, S

2014-06-01

Prospective evidence is inconsistent regarding the association between vegetable/fruit intake and the risk of gastric cancer. In an analysis of original data from four population-based prospective cohort studies encompassing 191 232 participants, we used Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of gastric cancer incidence according to vegetable and fruit intake and conducted a meta-analysis of HRs derived from each study. During 2 094 428 person-years of follow-up, 2995 gastric cancer cases were identified. After adjustment for potential confounders, we found a marginally significant decrease in gastric cancer risk in relation to total vegetable intake but not total fruit intake: the multivariate-adjusted HR (95% CI; P for trend) for the highest versus the lowest quintile of total vegetable intake was 0.89 (0.77-1.03; P for trend = 0.13) among men and 0.83 (0.67-1.03; P for trend = 0.40) among women. For distal gastric cancer, the multivariate HR for the highest quintile of total vegetable intake was 0.78 (0.63-0.97; P for trend = 0.02) among men. This pooled analysis of data from large prospective studies in Japan suggests that vegetable intake reduces gastric cancer risk, especially the risk of distal gastric cancer among men. © The Author 2014. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

78 FR 11611 - Current Good Manufacturing Practice and Hazard Analysis and Risk-Based Preventive Controls for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-19

... Manufacturing Practice and Hazard Analysis and Risk- Based Preventive Controls for Human Food; Extension of... Analysis and Risk-Based Preventive Controls for Human Food.'' FOR FURTHER INFORMATION CONTACT: Domini Bean... Practice and Hazard Analysis and Risk-Based Preventive Controls for Human Food'' with a 120-day comment...

Effects of cobalt-chromium everolimus eluting stents or bare metal stent on fatal and non-fatal cardiovascular events: patient level meta-analysis

PubMed Central

Sabaté, Manel; Kaiser, Christoph; Brugaletta, Salvatore; de la Torre Hernandez, Jose Maria; Galatius, Soeren; Cequier, Angel; Eberli, Franz; de Belder, Adam; Serruys, Patrick W; Ferrante, Giuseppe

2014-01-01

Objectives To examine the safety and effectiveness of cobalt-chromium everolimus eluting stents compared with bare metal stents. Design Individual patient data meta-analysis of randomised controlled trials. Cox proportional regression models stratified by trial, containing random effects, were used to assess the impact of stent type on outcomes. Hazard ratios with 95% confidence interval for outcomes were reported. Data sources and study selection Medline, Embase, the Cochrane Central Register of Controlled Trials. Randomised controlled trials that compared cobalt-chromium everolimus eluting stents with bare metal stents were selected. The principal investigators whose trials met the inclusion criteria provided data for individual patients. Primary outcomes The primary outcome was cardiac mortality. Secondary endpoints were myocardial infarction, definite stent thrombosis, definite or probable stent thrombosis, target vessel revascularisation, and all cause death. Results The search yielded five randomised controlled trials, comprising 4896 participants. Compared with patients receiving bare metal stents, participants receiving cobalt-chromium everolimus eluting stents had a significant reduction of cardiac mortality (hazard ratio 0.67, 95% confidence interval 0.49 to 0.91; P=0.01), myocardial infarction (0.71, 0.55 to 0.92; P=0.01), definite stent thrombosis (0.41, 0.22 to 0.76; P=0.005), definite or probable stent thrombosis (0.48, 0.31 to 0.73; P<0.001), and target vessel revascularisation (0.29, 0.20 to 0.41; P<0.001) at a median follow-up of 720 days. There was no significant difference in all cause death between groups (0.83, 0.65 to 1.06; P=0.14). Findings remained unchanged at multivariable regression after adjustment for the acuity of clinical syndrome (for instance, acute coronary syndrome v stable coronary artery disease), diabetes mellitus, female sex, use of glycoprotein IIb/IIIa inhibitors, and up to one year v longer duration treatment with dual antiplatelets. Conclusions This meta-analysis offers evidence that compared with bare metal stents the use of cobalt-chromium everolimus eluting stents improves global cardiovascular outcomes including cardiac survival, myocardial infarction, and overall stent thrombosis. PMID:25378023

Effects of cobalt-chromium everolimus eluting stents or bare metal stent on fatal and non-fatal cardiovascular events: patient level meta-analysis.

PubMed

Valgimigli, Marco; Sabaté, Manel; Kaiser, Christoph; Brugaletta, Salvatore; de la Torre Hernandez, Jose Maria; Galatius, Soeren; Cequier, Angel; Eberli, Franz; de Belder, Adam; Serruys, Patrick W; Ferrante, Giuseppe

2014-11-04

To examine the safety and effectiveness of cobalt-chromium everolimus eluting stents compared with bare metal stents. Individual patient data meta-analysis of randomised controlled trials. Cox proportional regression models stratified by trial, containing random effects, were used to assess the impact of stent type on outcomes. Hazard ratios with 95% confidence interval for outcomes were reported. Medline, Embase, the Cochrane Central Register of Controlled Trials. Randomised controlled trials that compared cobalt-chromium everolimus eluting stents with bare metal stents were selected. The principal investigators whose trials met the inclusion criteria provided data for individual patients. The primary outcome was cardiac mortality. Secondary endpoints were myocardial infarction, definite stent thrombosis, definite or probable stent thrombosis, target vessel revascularisation, and all cause death. The search yielded five randomised controlled trials, comprising 4896 participants. Compared with patients receiving bare metal stents, participants receiving cobalt-chromium everolimus eluting stents had a significant reduction of cardiac mortality (hazard ratio 0.67, 95% confidence interval 0.49 to 0.91; P=0.01), myocardial infarction (0.71, 0.55 to 0.92; P=0.01), definite stent thrombosis (0.41, 0.22 to 0.76; P=0.005), definite or probable stent thrombosis (0.48, 0.31 to 0.73; P<0.001), and target vessel revascularisation (0.29, 0.20 to 0.41; P<0.001) at a median follow-up of 720 days. There was no significant difference in all cause death between groups (0.83, 0.65 to 1.06; P=0.14). Findings remained unchanged at multivariable regression after adjustment for the acuity of clinical syndrome (for instance, acute coronary syndrome v stable coronary artery disease), diabetes mellitus, female sex, use of glycoprotein IIb/IIIa inhibitors, and up to one year v longer duration treatment with dual antiplatelets. This meta-analysis offers evidence that compared with bare metal stents the use of cobalt-chromium everolimus eluting stents improves global cardiovascular outcomes including cardiac survival, myocardial infarction, and overall stent thrombosis. © Valgimigli et al 2014.

Repeated blood transfusions: Identification of a novel culprit of early graft failure in children.

PubMed

Therrien, Judith; Guo, Kenneth; Guo, Liming; Liu, Aihua; Marelli, Ariane

2018-03-01

The attrition of right ventricle to pulmonary artery (RV-PA) grafts has been attributed in part to the body's immunologic response. We hypothesized that antibodies developed through blood transfusion, directed against the grafts, may result in accelerated degeneration and the need for re-intervention. This is a population-based study of the province of Quebec. We included children born between January 1, 1987 to December 31, 2006 who were diagnosed with a cono-truncal anomaly and had an RV-PA graft. The patients were followed for transfusion exposure and RV-PA graft re-intervention. Time to re-intervention in those exposed versus non-exposed was analyzed using Cox regression. Analysis was done in two time periods, before and after the calendar year 2000, given the change in blood preparation in the province of Quebec. There were 413 patients who met the inclusion criteria of a cono-truncal disorder. Of the whole study population, 69% received a blood transfusion. Cox regression analysis showed that among patients who had the initial graft performed (n=181) before year 2000, having 2 or more blood transfusion was associated with an nearly tripled risk of a re-intervention comparing to no blood transfusion (hazard ratio of 2.88; 95% confidence interval 1.05-7.91). In patients who had the initial graft performed after year 2000 (n=232), the associated risk increase was 7-fold (hazard ratio of 7.01; 95% confidence interval 3.06-16.02). Kaplan-Meier analyses confirmed the significant difference in the re-intervention free survival probabilities between those who received 2 or more blood product transfusion and those who did not as well: prior to year 2000 (67.9% vs. 88.0% at 5years, p=0.0201) as well as after year 2000 (39.7% vs. 82.8% at 5years, p<0.0001). In this population-based analysis, repeated blood product transfusion was associated with a significant increased risk of a need for RV-PA graft re-intervention. This data strongly suggest that repeated blood transfusion may adversely impact graft longevity. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Older Age Predicts Decreased Metastasis and Prostate Cancer-Specific Death for Men Treated With Radiation Therapy: Meta-Analysis of Radiation Therapy Oncology Group Trials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamstra, Daniel A., E-mail: dhamm@umich.edu; Bae, Kyounghwa; Pilepich, Miljenko V.

2011-12-01

Purpose: The impact of age on prostate cancer (PCa) outcome has been controversial; therefore, we analyzed the effect of age on overall survival (OS), distant metastasis, prostate cancer-specific death (PCSD), and nonprostate cancer death (NPCD) on patients with locally advanced PCa. Methods and Materials: Patients who participated in four Radiation Therapy Oncology Group (RTOG) phase III trials, 8531, 8610, 9202, and 9413, were studied. Cox proportional hazards regression was used for OS analysis, and cumulative events analysis with Fine and Gray's regression was used for analyses of metastasis, PCSD, and NPCD. Results: Median follow-up of 4,128 patients with median agemore » of 70 (range, 43-88 years) was 7.3 years. Most patients had high-risk disease: cT3 to cT4 (54%) and Gleason scores (GS) of 7 (45%) and 8 to 10 (27%). Older age ({<=}70 vs. >70 years) predicted for decreased OS (10-year rate, 55% vs. 41%, respectively; p < 0.0001) and increased NPCD (10-year rate, 28% vs. 46%, respectively; p < 0.0001) but decreased metastasis (10-year rate, 27% vs. 20%, respectively; p < 0.0001) and PCSD (10-year rate, 18% vs. 14%, respectively; p < 0.0001). To account for competing risks, outcomes were analyzed in 2-year intervals, and age-dependent differences in metastasis and PCSD persisted, even in the earliest time periods. When adjusted for other covariates, an age of >70 years remained associated with decreased OS (hazard ratio [HR], 1.56 [95% confidence interval [CI], 1.43-1.70] p < 0.0001) but with decreased metastasis (HR, 0.72 [95% CI, 0.63-0.83] p < 0.0001) and PCSD (HR, 0.78 [95% CI, 0.66-0.92] p < 0.0001). Finally, the impact of the duration of androgen deprivation therapy as a function of age was evaluated. Conclusions: These data support less aggressive PCa in older men, independent of other clinical features. While the biological underpinning of this finding remains unknown, stratification by age in future trials appears to be warranted.« less

Eicosapentaenoic acid to arachidonic acid (EPA/AA) ratio as an associated factor of high risk plaque on coronary computed tomography in patients without coronary artery disease.

PubMed

Nagahara, Yasuomi; Motoyama, Sadako; Sarai, Masayoshi; Ito, Hajime; Kawai, Hideki; Takakuwa, Yoko; Miyagi, Meiko; Shibata, Daisuke; Takahashi, Hiroshi; Naruse, Hiroyuki; Ishii, Junichi; Ozaki, Yukio

2016-07-01

Coronary computed tomography angiography (CCTA)-verified high risk plaque (HRP) characteristics including positive remodeling and low attenuation plaque have been associated with acute coronary syndromes. Several studies reported that the n-3 polyunsaturated fatty acids have been associated with cardiovascular events. However, the relationship between serum eicosapentaenoic acid to arachidonic acid (EPA/AA) ratio and CCTA-verified HRP in patients without known coronary artery disease (CAD) is unclear. We aimed at investigating the relation between EPA/AA and CCTA-verified HRP in patients without known CAD. We included 193 patients undergoing CCTA without known CAD (65.5 ± 12.0 years, 55.0% male). No patient has been treated with EPA. The relation of coronary risk factors, lipid profile, high-sensitivity C-reactive protein, coronary artery calcification score (CACS), number of vessel disease, plaque burden, and EPA/AA with the presence of HRP was evaluated by logistic regression analysis. Incremental value of EPA/AA to predict HRP was also analyzed by C-index, NRI, and IDI. A Cox proportional hazards model was used to estimate the time to cardiovascular event. HRP was observed in 37 (19%) patients. Multivariable logistic regression analysis revealed that current smoking (OR 2.58; p=0.046), number of vessel disease (OR 1.87; p=0.031), and EPA/AA ratio (OR 0.65; p=0.0006) were independent associated factors of HRP on CCTA. Although the addition of EPA/AA to the baseline model did not significantly improve C-index, both NRI (0.60, p=0.0049) and IDI (0.054, p=0.0072) were significantly improved. Patients with HRP had significantly higher rate of events compared with patients without HRP (14% vs. 3%, Logrank p=0.0004). On multivariable Cox hazard analysis, baseline EPA/AA ratio was an independent predictor (HR 0.57, p=0.047). Low EPA/AA was an associated factor of HRP on CCTA in patients without CAD. In addition to conventional coronary risk factors and CACS, EPA/AA and CCTA might be useful for risk stratification of CAD. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Predictive Models of target organ and Systemic toxicities (BOSC)

EPA Science Inventory

The objective of this work is to predict the hazard classification and point of departure (PoD) of untested chemicals in repeat-dose animal testing studies. We used supervised machine learning to objectively evaluate the predictive accuracy of different classification and regress...

Cisplatin and Etoposide Versus Carboplatin and Paclitaxel With Concurrent Radiotherapy for Stage III Non–Small-Cell Lung Cancer: An Analysis of Veterans Health Administration Data

PubMed Central

Santana-Davila, Rafael; Devisetty, Kiran; Szabo, Aniko; Sparapani, Rodney; Arce-Lara, Carlos; Gore, Elizabeth M.; Moran, Amy; Williams, Christina D.; Kelley, Michael J.; Whittle, Jeffrey

2015-01-01

Purpose The optimal chemotherapy regimen to use with radiotherapy in stage III non–small-cell lung cancer is unknown. Here, we compare the outcome of patents treated within the Veterans Health Administration with either etoposide-cisplatin (EP) or carboplatin-paclitaxel (CP). Methods We identified patients treated with EP and CP with concurrent radiotherapy from 2001 to 2010. Survival rates were compared using Cox proportional hazards regression models with adjustments for confounding provided by propensity score methods and an instrumental variables analysis. Comorbidities and treatment complications were identified through administrative data. Results A total of 1,842 patients were included; EP was used in 27% (n = 499). Treatment with EP was not associated with a survival advantage in a Cox proportional hazards model (hazard ratio [HR], 0.97; 95% CI, 0.85 to 1.10), a propensity score matched cohort (HR, 1.07; 95% CI, 0.91 to 1.24), or a propensity score adjusted model (HR, 0.97; 95% CI, 0.85 to 1.10). In an instrumental variables analysis, there was no survival advantage for patients treated in centers where EP was used more than 50% of the time as compared with centers where EP was used in less than 10% of the patients (HR, 1.07; 95% CI, 0.90 to 1.26). Patients treated with EP, compared with patients treated with CP, had more hospitalizations (2.4 v 1.7 hospitalizations, respectively; P < .001), outpatient visits (17.6 v 12.6 visits, respectively; P < .001), infectious complications (47.3% v 39.4%, respectively; P = .0022), acute kidney disease/dehydration (30.5% v 21.2%, respectively; P < .001), and mucositis/esophagitis (18.6% v 14.4%, respectively; P = .0246). Conclusion After accounting for prognostic variables, patients treated with EP versus CP had similar overall survival, but EP was associated with increased morbidity. PMID:25422491

Health behaviours as a predictor of quitting hazardous alcohol use in the Stockholm Public Health Cohort.

PubMed

Säfsten, Eleonor; Forsell, Yvonne; Ramstedt, Mats; Galanti, Maria R

2018-06-01

Adopting healthy behaviours may facilitate the transition from hazardous to non-hazardous use of alcohol, yet, longitudinal studies of health behaviours in relation to the cessation of hazardous alcohol use are rare. We addressed this question using data from a large population-based cohort of adults in Sweden (Stockholm Public Health Cohort). Participants from two sub-cohorts (inception in 2002 and 2010), with follow-up until the year 2014 were included. Health behaviours (tobacco use, diet and physical activity) and alcohol use were self-reported in questionnaire-based surveys. Hazardous alcohol use was defined as either usual weekly consumption (2002 sub-cohort) or heavy occasional alcohol consumption (2010 sub-cohort). Baseline hazardous drinkers with complete data constituted the analytical sample (n = 8946). Logistic regression was used to calculate the Odds Ratios and their 95% confidence intervals of quitting hazardous alcohol use, with tobacco use, diet and physical activity as predictors of change. In the 2002 sub-cohort, 28% reported non-hazardous use sustained through two consecutive follow-up points. In the 2010 sub-cohort, 36% of the participants reported non-hazardous use of alcohol at follow-up. Favourable health behaviours at baseline (e.g. no tobacco use, sufficient fruit intake and physical activity) were associated with a 19% to 75% higher of odds quitting hazardous alcohol use. Further, favourable changes in diet and tobacco cessation were associated with non-hazardous alcohol use at follow-up. As many as one-third of hazardous alcohol users may quit this drinking pattern in a medium-long term. Holding or achieving a healthy lifestyle may facilitate this transition.

Characteristics and predictors of home injury hazards among toddlers in Wenzhou, China: a community-based cross-sectional study

PubMed Central

2014-01-01

Background Home hazards are associated with toddlers receiving unintentional home injuries (UHI). These result in not only physical and psychological difficulties for children, but also economic losses and additional stress for their families. Few researchers pay attention to predictors of home hazards among toddlers in a systematic way. The purpose of this study is firstly to describe the characteristics of homes with hazards and secondly to explore the predicted relationship of children, parents and family factors to home hazards among toddlers aged 24–47 months in Wenzhou, China. Methods A random cluster sampling was employed to select 366 parents having children aged 24 – 47 months from 13 kindergartens between March and April of 2012. Four instruments assessed home hazards, demographics, parent’s awareness of UHI, as well as family functioning. Results Descriptive statistics showed that the mean of home hazards was 12.29 (SD = 6.39). The nine kinds of home hazards that were identified in over 50% of households were: plastic bags (74.3%), coin buttons (69.1%), and toys with small components (66.7%) etc. Multivariate linear regression revealed that the predictors of home hazards were the child’s age, the child’s residential status and family functioning (b = .19, 2.02, - .07, p < .01, < .05 and < .01, respectively). Conclusions The results showed that a higher number of home hazards were significantly attributed to older toddlers, migrant toddlers and poorer family functioning. This result suggested that heath care providers should focus on the vulnerable family and help the parents assess home hazards. Further study is needed to find interventions on how to manage home hazards for toddlers in China. PMID:24953678

Modeling and Hazard Analysis Using STPA

NASA Astrophysics Data System (ADS)

Ishimatsu, Takuto; Leveson, Nancy; Thomas, John; Katahira, Masa; Miyamoto, Yuko; Nakao, Haruka

2010-09-01

A joint research project between MIT and JAXA/JAMSS is investigating the application of a new hazard analysis to the system and software in the HTV. Traditional hazard analysis focuses on component failures but software does not fail in this way. Software most often contributes to accidents by commanding the spacecraft into an unsafe state(e.g., turning off the descent engines prematurely) or by not issuing required commands. That makes the standard hazard analysis techniques of limited usefulness on software-intensive systems, which describes most spacecraft built today. STPA is a new hazard analysis technique based on systems theory rather than reliability theory. It treats safety as a control problem rather than a failure problem. The goal of STPA, which is to create a set of scenarios that can lead to a hazard, is the same as FTA but STPA includes a broader set of potential scenarios including those in which no failures occur but the problems arise due to unsafe and unintended interactions among the system components. STPA also provides more guidance to the analysts that traditional fault tree analysis. Functional control diagrams are used to guide the analysis. In addition, JAXA uses a model-based system engineering development environment(created originally by Leveson and called SpecTRM) which also assists in the hazard analysis. One of the advantages of STPA is that it can be applied early in the system engineering and development process in a safety-driven design process where hazard analysis drives the design decisions rather than waiting until reviews identify problems that are then costly or difficult to fix. It can also be applied in an after-the-fact analysis and hazard assessment, which is what we did in this case study. This paper describes the experimental application of STPA to the JAXA HTV in order to determine the feasibility and usefulness of the new hazard analysis technique. Because the HTV was originally developed using fault tree analysis and following the NASA standards for safety-critical systems, the results of our experimental application of STPA can be compared with these more traditional safety engineering approaches in terms of the problems identified and the resources required to use it.

Empirical ground-motion relations for subduction-zone earthquakes and their application to Cascadia and other regions

USGS Publications Warehouse

Atkinson, G.M.; Boore, D.M.

2003-01-01

Ground-motion relations for earthquakes that occur in subduction zones are an important input to seismic-hazard analyses in many parts of the world. In the Cascadia region (Washington, Oregon, northern California, and British Columbia), for example, there is a significant hazard from megathrust earthquakes along the subduction interface and from large events within the subducting slab. These hazards are in addition to the hazard from shallow earthquakes in the overlying crust. We have compiled a response spectra database from thousands of strong-motion recordings from events of moment magnitude (M) 5-8.3 occurring in subduction zones around the world, including both interface and in-slab events. The 2001 M 6.8 Nisqually and 1999 M 5.9 Satsop earthquakes are included in the database, as are many records from subduction zones in Japan (Kyoshin-Net data), Mexico (Guerrero data), and Central America. The size of the database is four times larger than that available for previous empirical regressions to determine ground-motion relations for subduction-zone earthquakes. The large dataset enables improved determination of attenuation parameters and magnitude scaling, for both interface and in-slab events. Soil response parameters are also better determined by the data. We use the database to develop global ground-motion relations for interface and in-slab earthquakes, using a maximum likelihood regression method. We analyze regional variability of ground-motion amplitudes across the global database and find that there are significant regional differences. In particular, amplitudes in Cascadia differ by more than a factor of 2 from those in Japan for the same magnitude, distance, event type, and National Earthquake Hazards Reduction Program (NEHRP) soil class. This is believed to be due to regional differences in the depth of the soil profile, which are not captured by the NEHRP site classification scheme. Regional correction factors to account for these differences are proposed for Cascadia and Japan. The results of this study differ significantly from previous analyses based on more limited data and have important implications for seismic-hazard analysis. The ground-motion relations predict that a great megathrust earthquake (M ???8) at a fault distance of about 100 km would produce pseudoacceleration (PSA), 5% damped, horizontal component on soil sites of about 110 cm/sec2 at 0.5 Hz, 660 cm/sec2 at 2.5 Hz, and 410 cm/sec2 at 5 Hz, with a peak ground acceleration of about 180 cm/ sec2 . These damaging levels of motion would be experienced over a very large area, corresponding to a rectangular area about 300 km wide by 500 km long. Large in-slab events (M 7.5) would produce even higher PSA values within 100 km of the fault, but the in-slab motions attenuate much more rapidly with distance. Thus the hazard posed by moderate to large in-slab events such as the 2001 Nisqually earthquake is modest compared to that of a Cascadia megathrust earthquake of M ???8, in terms of the area that would experience damaging levels of ground motion.

Nomogram Prediction of Overall Survival After Curative Irradiation for Uterine Cervical Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seo, YoungSeok; Yoo, Seong Yul; Kim, Mi-Sook

Purpose: The purpose of this study was to develop a nomogram capable of predicting the probability of 5-year survival after radical radiotherapy (RT) without chemotherapy for uterine cervical cancer. Methods and Materials: We retrospectively analyzed 549 patients that underwent radical RT for uterine cervical cancer between March 1994 and April 2002 at our institution. Multivariate analysis using Cox proportional hazards regression was performed and this Cox model was used as the basis for the devised nomogram. The model was internally validated for discrimination and calibration by bootstrap resampling. Results: By multivariate regression analysis, the model showed that age, hemoglobin levelmore » before RT, Federation Internationale de Gynecologie Obstetrique (FIGO) stage, maximal tumor diameter, lymph node status, and RT dose at Point A significantly predicted overall survival. The survival prediction model demonstrated good calibration and discrimination. The bootstrap-corrected concordance index was 0.67. The predictive ability of the nomogram proved to be superior to FIGO stage (p = 0.01). Conclusions: The devised nomogram offers a significantly better level of discrimination than the FIGO staging system. In particular, it improves predictions of survival probability and could be useful for counseling patients, choosing treatment modalities and schedules, and designing clinical trials. However, before this nomogram is used clinically, it should be externally validated.« less

Stream profile analysis using a step backwater model for selected reaches in the Chippewa Creek basin in Medina, Wayne, and Summit Counties, Ohio

USGS Publications Warehouse

Straub, David E.; Ebner, Andrew D.

2011-01-01

The USGS, in cooperation with the Chippewa Subdistrict of the Muskingum Watershed Conservancy District, performed hydrologic and hydraulic analyses for selected reaches of three streams in Medina, Wayne, Stark, and Summit Counties in northeast Ohio: Chippewa Creek, Little Chippewa Creek, and River Styx. This study was done to facilitate assessment of various alternatives for mitigating flood hazards in the Chippewa Creek basin. StreamStats regional regression equations were used to estimate instantaneous peak discharges approximately corresponding to bankfull flows. Explanatory variables used in the regression equations were drainage area, main-channel slope, and storage area. Hydraulic models were developed to determine water-surface profiles along the three stream reaches studied for the bankfull discharges established in the hydrologic analyses. The HEC-RAS step-backwater hydraulic analysis model was used to determine water-surface profiles for the three streams. Starting water-surface elevations for all streams were established using normal depth computations in the HEC-RAS models. Cross-sectional elevation data, hydraulic-structure geometries, and roughness coefficients were collected in the field and (along with peak-discharge estimates) used as input for the models. Reach-averaged reductions in water-surface elevations ranged from 0.11 to 1.29 feet over the four roughness coefficient reduction scenarios.

Spatial patterns and origins of heavy metals in Sheyang River catchment in Jiangsu, China based on geographically weighted regression.

PubMed

Wu, Shan-Shan; Yang, Hao; Guo, Fei; Han, Rui-Ming

2017-02-15

Multivariate statistical analyses combined with geographically weighted regression (GWR) were used to identify spatial variations of heavy metals in sediments and to examine relationships between metal pollution and land use practices in watersheds, including urban land, agriculture land, forest and water bodies. Seven metals (Cu, Zn, Pb, Cr, Ni, Mn and Fe) of sediments were measured at 31 sampling sites in Sheyang River. Most metals were under a certain degree enrichment based on the enrichment factors. Cluster analysis grouped all sites into four statistically significant cluster, severely contaminated areas were concentrated in areas with intensive human activities. Correlation analysis and PCA indicated Cu, Zn and Pb were derived from anthropogenic activities, while the sources of Cr and Ni were complicated. However, Fe and Mn originated from natural sources. According to results of GWR, there are stronger association between metal pollution with urban land than agricultural land and forest. Moreover, the relationships between land use and metal concentration were affected by the urbanization level of watersheds. Agricultural land had a weak associated with heavy metal pollution and the relationships might be stronger in less-urbanized. This study provided useful information for the assessment and management of heavy metal hazards in studied area. Copyright © 2016 Elsevier B.V. All rights reserved.

Non-Intrusive Measurement Techniques Applied to the Hybrid Solid Fuel Degradation

NASA Astrophysics Data System (ADS)

Cauty, F.

2004-10-01

The knowledge of the solid fuel regression rate and the time evolution of the grain geometry are requested for hybrid motor design and control of its operating conditions. Two non-intrusive techniques (NDT) have been applied to hybrid propulsion : both are based on wave propagation, the X-rays and the ultrasounds, through the materials. X-ray techniques allow local thickness measurements (attenuated signal level) using small probes or 2D images (Real Time Radiography), with a link between the size of field of view and accuracy. Beside the safety hazards associated with the high-intensity X-ray systems, the image analysis requires the use of quite complex post-processing techniques. The ultrasound technique is more widely used in energetic material applications, including hybrid fuels. Depending upon the transducer size and the associated equipment, the application domain is large, from tiny samples to the quad-port wagon wheel grain of the 1.1 MN thrust HPDP motor. The effect of the physical quantities has to be taken into account in the wave propagation analysis. With respect to the various applications, there is no unique and perfect experimental method to measure the fuel regression rate. The best solution could be obtained by combining two techniques at the same time, each technique enhancing the quality of the global data.

Inverse odds ratio-weighted estimation for causal mediation analysis.

PubMed

Tchetgen Tchetgen, Eric J

2013-11-20

An important scientific goal of studies in the health and social sciences is increasingly to determine to what extent the total effect of a point exposure is mediated by an intermediate variable on the causal pathway between the exposure and the outcome. A causal framework has recently been proposed for mediation analysis, which gives rise to new definitions, formal identification results and novel estimators of direct and indirect effects. In the present paper, the author describes a new inverse odds ratio-weighted approach to estimate so-called natural direct and indirect effects. The approach, which uses as a weight the inverse of an estimate of the odds ratio function relating the exposure and the mediator, is universal in that it can be used to decompose total effects in a number of regression models commonly used in practice. Specifically, the approach may be used for effect decomposition in generalized linear models with a nonlinear link function, and in a number of other commonly used models such as the Cox proportional hazards regression for a survival outcome. The approach is simple and can be implemented in standard software provided a weight can be specified for each observation. An additional advantage of the method is that it easily incorporates multiple mediators of a categorical, discrete or continuous nature. Copyright © 2013 John Wiley & Sons, Ltd.

Hazardous Alcohol Use in 2 Countries: A Comparison Between Alberta, Canada and Queensland, Australia

PubMed Central

Voaklander, Donald

2017-01-01

Objectives This article aimed to compare alcohol consumption between the populations of Queensland in Australia and Alberta in Canada. Furthermore, the associations between greater alcohol consumption and socio-demographic characteristics were explored in each population. Methods Data from 2500 participants of the 2013 Alberta Survey and the 2013 Queensland Social Survey were analyzed. Regression analyses were used to explore the associations between alcohol risk and socio-demographic characteristics. Results A higher rate of hazardous alcohol use was found in Queenslanders than in Albertans. In both Albertans and Queenslanders, hazardous alcohol use was associated with being between 18 and 24 years of age. Higher income, having no religion, living alone, and being born in Canada were also associated with alcohol risk in Albertans; while in Queenslanders, hazardous alcohol use was also associated with common-law marital status. In addition, hazardous alcohol use was lower among respondents with a non-Catholic or Protestant religious affiliation. Conclusions Younger age was associated with greater hazardous alcohol use in both populations. In addition, different socio-demographic factors were associated with hazardous alcohol use in each of the populations studied. Our results allowed us to identify the socio-demographic profiles associated with hazardous alcohol use in Alberta and Queensland. These profiles constitute valuable sources of information for local health authorities and policymakers when designing suitable preventive strategies targeting hazardous alcohol use. Overall, the present study highlights the importance of analyzing the socio-demographic factors associated with alcohol consumption in population-specific contexts. PMID:29020759

Reported Theory Use by Digital Interventions for Hazardous and Harmful Alcohol Consumption, and Association With Effectiveness: Meta-Regression.

PubMed

Garnett, Claire; Crane, David; Brown, Jamie; Kaner, Eileen; Beyer, Fiona; Muirhead, Colin; Hickman, Matthew; Redmore, James; de Vocht, Frank; Beard, Emma; Michie, Susan

2018-02-28

Applying theory to the design and evaluation of interventions is likely to increase effectiveness and improve the evidence base from which future interventions are developed, though few interventions report this. The aim of this paper was to assess how digital interventions to reduce hazardous and harmful alcohol consumption report the use of theory in their development and evaluation, and whether reporting of theory use is associated with intervention effectiveness. Randomized controlled trials were extracted from a Cochrane review on digital interventions for reducing hazardous and harmful alcohol consumption. Reporting of theory use within these digital interventions was investigated using the theory coding scheme (TCS). Reported theory use was analyzed by frequency counts and descriptive statistics. Associations were analyzed with meta-regression models. Of 41 trials involving 42 comparisons, half did not mention theory (50% [21/42]), and only 38% (16/42) used theory to select or develop the intervention techniques. Significant heterogeneity existed between studies in the effect of interventions on alcohol reduction (I 2 =77.6%, P<.001). No significant associations were detected between reporting of theory use and intervention effectiveness in unadjusted models, though the meta-regression was underpowered to detect modest associations. Digital interventions offer a unique opportunity to refine and develop new dynamic, temporally sensitive theories, yet none of the studies reported refining or developing theory. Clearer selection, application, and reporting of theory use is needed to accurately assess how useful theory is in this field and to advance the field of behavior change theories. ©Claire Garnett, David Crane, Jamie Brown, Eileen Kaner, Fiona Beyer, Colin Muirhead, Matthew Hickman, James Redmore, Frank de Vocht, Emma Beard, Susan Michie. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 28.02.2018.

Parameter estimation in Cox models with missing failure indicators and the OPPERA study.

PubMed

Brownstein, Naomi C; Cai, Jianwen; Slade, Gary D; Bair, Eric

2015-12-30

In a prospective cohort study, examining all participants for incidence of the condition of interest may be prohibitively expensive. For example, the "gold standard" for diagnosing temporomandibular disorder (TMD) is a physical examination by a trained clinician. In large studies, examining all participants in this manner is infeasible. Instead, it is common to use questionnaires to screen for incidence of TMD and perform the "gold standard" examination only on participants who screen positively. Unfortunately, some participants may leave the study before receiving the "gold standard" examination. Within the framework of survival analysis, this results in missing failure indicators. Motivated by the Orofacial Pain: Prospective Evaluation and Risk Assessment (OPPERA) study, a large cohort study of TMD, we propose a method for parameter estimation in survival models with missing failure indicators. We estimate the probability of being an incident case for those lacking a "gold standard" examination using logistic regression. These estimated probabilities are used to generate multiple imputations of case status for each missing examination that are combined with observed data in appropriate regression models. The variance introduced by the procedure is estimated using multiple imputation. The method can be used to estimate both regression coefficients in Cox proportional hazard models as well as incidence rates using Poisson regression. We simulate data with missing failure indicators and show that our method performs as well as or better than competing methods. Finally, we apply the proposed method to data from the OPPERA study. Copyright © 2015 John Wiley & Sons, Ltd.

Analysis of cohort studies with multivariate and partially observed disease classification data.

PubMed

Chatterjee, Nilanjan; Sinha, Samiran; Diver, W Ryan; Feigelson, Heather Spencer

2010-09-01

Complex diseases like cancers can often be classified into subtypes using various pathological and molecular traits of the disease. In this article, we develop methods for analysis of disease incidence in cohort studies incorporating data on multiple disease traits using a two-stage semiparametric Cox proportional hazards regression model that allows one to examine the heterogeneity in the effect of the covariates by the levels of the different disease traits. For inference in the presence of missing disease traits, we propose a generalization of an estimating equation approach for handling missing cause of failure in competing-risk data. We prove asymptotic unbiasedness of the estimating equation method under a general missing-at-random assumption and propose a novel influence-function-based sandwich variance estimator. The methods are illustrated using simulation studies and a real data application involving the Cancer Prevention Study II nutrition cohort.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lindbohm, M.L.; Hemminki, K.; Kyyroenen, P.

Spontaneous abortions were analyzed by the occupational exposure of women and their husbands, with data from the Finnish hospital discharge register and the national census. The occupations were grouped according to presumed exposure into seven categories: exposure to solvent; automobile exhaust fumes; polycyclic aromatic hydrocarbons; other chemicals; metals; textile dust; and animal microorganisms. The relative risks of spontaneous abortion were estimated with logistic regression analysis to adjust for potentially confounding factors. The broad exposure categories appeared, at most, to be weak risk factors of spontaneous abortion, because the relative risks of abortion were not significantly increased in any of themore » parental exposure groups. The analysis of detailed occupational categories showed some female and male occupations with an increased risk. The observations of increased risk related to laboratory work supported earlier findings. The high number of textile occupations with increased risk is also worth noting, and further investigations are necessary to confirm whether this is due to occupational hazards or other factors.« less

Joint Modeling Approach for Semicompeting Risks Data with Missing Nonterminal Event Status

PubMed Central

Hu, Chen; Tsodikov, Alex

2014-01-01

Semicompeting risks data, where a subject may experience sequential non-terminal and terminal events, and the terminal event may censor the non-terminal event but not vice versa, are widely available in many biomedical studies. We consider the situation when a proportion of subjects’ non-terminal events is missing, such that the observed data become a mixture of “true” semicompeting risks data and partially observed terminal event only data. An illness-death multistate model with proportional hazards assumptions is proposed to study the relationship between non-terminal and terminal events, and provide covariate-specific global and local association measures. Maximum likelihood estimation based on semiparametric regression analysis is used for statistical inference, and asymptotic properties of proposed estimators are studied using empirical process and martingale arguments. We illustrate the proposed method with simulation studies and data analysis of a follicular cell lymphoma study. PMID:24430204

Risk analysis based on hazards interactions

NASA Astrophysics Data System (ADS)

Rossi, Lauro; Rudari, Roberto; Trasforini, Eva; De Angeli, Silvia; Becker, Joost

2017-04-01

Despite an increasing need for open, transparent, and credible multi-hazard risk assessment methods, models, and tools, the availability of comprehensive risk information needed to inform disaster risk reduction is limited, and the level of interaction across hazards is not systematically analysed. Risk assessment methodologies for different hazards often produce risk metrics that are not comparable. Hazard interactions (consecutive occurrence two or more different events) are generally neglected, resulting in strongly underestimated risk assessment in the most exposed areas. This study presents cases of interaction between different hazards, showing how subsidence can affect coastal and river flood risk (Jakarta and Bandung, Indonesia) or how flood risk is modified after a seismic event (Italy). The analysis of well documented real study cases, based on a combination between Earth Observation and in-situ data, would serve as basis the formalisation of a multi-hazard methodology, identifying gaps and research frontiers. Multi-hazard risk analysis is performed through the RASOR platform (Rapid Analysis and Spatialisation Of Risk). A scenario-driven query system allow users to simulate future scenarios based on existing and assumed conditions, to compare with historical scenarios, and to model multi-hazard risk both before and during an event (www.rasor.eu).

Hypoglycaemia with oral antidiabetic drugs: results from prescription-event monitoring cohorts of rosiglitazone, pioglitazone, nateglinide and repaglinide.

PubMed

Vlckova, Veronika; Cornelius, Victoria; Kasliwal, Rachna; Wilton, Lynda; Shakir, Saad A W

2009-01-01

Hypoglycaemia is an acute complication associated with intensive treatment of patients with diabetes mellitus. This complication poses a major challenge in diabetes management. Furthermore, severe hypoglycaemia may be life threatening. Although hypoglycaemia is more often associated with insulin treatment, oral hypoglycaemic agents have the potential to trigger hypoglycaemia. The aim of this study was to quantify the incidence of hypoglycaemic events and to describe the pattern of these incident events during the first 9 months of treatment with four oral antidiabetic drugs, rosiglitazone, pioglitazone, nateglinide and repaglinide, prescribed in general practice in England. We used data collected for prescription-event monitoring (PEM) studies of rosiglitazone, pioglitazone, nateglinide and repaglinide. PEM is an observational, non-interventional, incept cohort study. Observation time for each patient and incidence rate (IR) per 1000 patient-years of treatment for hypoglycaemia was calculated for each drug cohort. Smoothed hazard estimates were plotted over time. Case/non-case analysis was performed to describe and compare patients who had at least one hypoglycaemic event in the first 9 months of treatment with those who did not. The total number of patients included in the analysis was 14,373, 12,768, 4,549 and 5,727 in rosiglitazone, pioglitazone, nateglinide and repaglinide cohorts, respectively. From these, 276 patients experienced at least one episode of hypoglycaemia. The IR was between 50% and 100% higher in patients receiving treatment with meglitinides compared with those treated with the thiazolidinediones (TZDs) [IR = 9.94, 9.64, 15.71 and 20.32 per 1,000 patient-years for rosiglitazone, pioglitazone, nateglinide and repaglinide, respectively]. The plot of the hazard function and the estimated shape parameter from the Weibull regression model showed that pioglitazone, nateglinide and repaglinide had non-constant (decreasing) hazards over time, whereas the hazard for rosiglitazone-treated patients was approximately constant over time. Nateglinide and repaglinide had similar shape hazard function, indicating a significantly higher number of hypoglycaemic episodes shortly after starting treatment. For women treated with TZDs, hypoglycaemia was reported more frequently than for men. This analysis shows that the frequency of reported hypoglycaemia within the study cohorts was relatively low. The rates of hypoglycaemia were not equal between drug classes. Treatment with nateglinide or repaglinide was characterized by a higher incidence of hypoglycaemia at the beginning of treatment. Further investigation is necessary to assess whether women treated with TZDs are more prone to hypoglycaemia than men. Findings from this study should be taken into account with other clinical and pharmacoepidemiological studies.

Dual oxidase 1: A predictive tool for the prognosis of hepatocellular carcinoma patients.

PubMed

Chen, Shengsen; Ling, Qingxia; Yu, Kangkang; Huang, Chong; Li, Ning; Zheng, Jianming; Bao, Suxia; Cheng, Qi; Zhu, Mengqi; Chen, Mingquan

2016-06-01

Dual oxidase 1 (DUOX1), which is the main source of reactive oxygen species (ROS) production in the airway, can be silenced in human lung cancer and hepatocellular carcinomas. However, the prognostic value of DUOX1 expression in hepatocellular carcinoma patients is still unclear. We investigated the prognostic value of DUOX1 expression in liver cancer patients. DUOX1 mRNA expression was determined in tumor tissues and non-tumor tissues by real‑time PCR. For evaluation of the prognostic value of DUOX1 expression, Kaplan-Meier method and Cox's proportional hazards model (univariate analysis and multivariate analysis) were employed. A simple risk score was devised by using significant variables obtained from the Cox's regression analysis to further predict the HCC patient prognosis. We observed a reduced DUOX1 mRNA level in the cancer tissues in comparison to the non‑cancer tissues. More importantly, Kaplan-Meier analysis showed that patients with high DUOX1 expression had longer disease-free survival and overall survival compared with those with low expression of DUOX1. Cox's regression analysis indicated that DUOX1 expression, age, and intrahepatic metastasis may be significant prognostic factors for disease-free survival and overall survival. Finally, we found that patients with total scores of >2 and >1 were more likely to relapse and succumb to the disease than patients whose total scores were ≤2 and ≤1. In conclusion, DUOX1 expression in liver tumors is a potential prognostic tool for patients. The risk scoring system is useful for predicting the survival of liver cancer patients after tumor resection.

Multivariable confounding adjustment in distributed data networks without sharing of patient-level data.

PubMed

Toh, Sengwee; Reichman, Marsha E; Houstoun, Monika; Ding, Xiao; Fireman, Bruce H; Gravel, Eric; Levenson, Mark; Li, Lingling; Moyneur, Erick; Shoaibi, Azadeh; Zornberg, Gwen; Hennessy, Sean

2013-11-01

It is increasingly necessary to analyze data from multiple sources when conducting public health safety surveillance or comparative effectiveness research. However, security, privacy, proprietary, and legal concerns often reduce data holders' willingness to share highly granular information. We describe and compare two approaches that do not require sharing of patient-level information to adjust for confounding in multi-site studies. We estimated the risks of angioedema associated with angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), and aliskiren in comparison with beta-blockers within Mini-Sentinel, which has created a distributed data system of 18 health plans. To obtain the adjusted hazard ratios (HRs) and 95% confidence intervals (CIs), we performed (i) a propensity score-stratified case-centered logistic regression analysis, a method identical to a stratified Cox regression analysis but needing only aggregated risk set data, and (ii) an inverse variance-weighted meta-analysis, which requires only the site-specific HR and variance. We also performed simulations to further compare the two methods. Compared with beta-blockers, the adjusted HR was 3.04 (95% CI: 2.81, 3.27) for ACEIs, 1.16 (1.00, 1.34) for ARBs, and 2.85 (1.34, 6.04) for aliskiren in the case-centered analysis. The corresponding HRs were 2.98 (2.76, 3.21), 1.15 (1.00, 1.33), and 2.86 (1.35, 6.04) in the meta-analysis. Simulations suggested that the two methods may produce different results under certain analytic scenarios. The case-centered analysis and the meta-analysis produced similar results without the need to share patient-level data across sites in our empirical study, but may provide different results in other study settings. Copyright © 2013 John Wiley & Sons, Ltd.

Midlife use of written Japanese and protection from late life dementia

PubMed Central

Crane, Paul K.; Gibbons, Laura E.; Arani, Keerthi; Nguyen, Viet; Rhoads, Kristoffer; McCurry, Susan M.; Launer, Lenore; Masaki, Kamal; White, Lon

2011-01-01

Background The cognitive reserve hypothesis would predict that use of written Japanese should confer protection against dementia because of the complexity of its ideograms compared with written English. We sought to test this hypothesis in analyses from a longitudinal study of Japanese-American men. Methods Participants were second-generation Japanese-American men (Nisei) on the island of Oahu, Hawaii, who were seen in 1965 and in subsequent examinations to detect dementia beginning in 1991-1993. Use of spoken and written Japanese was self-reported in 1965 (Analyses 1 and 2), and mid-life use of written Japanese and written English was self-reported in 1994-1996 (Analysis 3). We analyzed prevalent dementia outcomes in 1991-1993 (Analysis 1, n=3,139) using logistic regression, and incident dementia outcomes in 1994-2002 (Analysis 2, n=2,299) and in 1997-2002 (Analysis 3, n=1,655) using Cox proportional hazards regression. Dementia outcomes included all-cause dementia, probable and possible Alzheimer disease, and probable vascular dementia. We adjusted models for probable and possible confounders. Results Participants who reported proficiency with written Japanese were older and had lower incomes. For Analysis 1, there were 154 prevalent cases of dementia, 74 of Alzheimer disease, and 43 of vascular dementia; for Analysis 2, 236 incident cases of dementia, 138 of Alzheimer disease, and 45 of vascular dementia; and for Analysis 3, 125 incident cases of dementia, 80 of Alzheimer disease, and 20 of vascular dementia. There was no relationship in adjusted models between self-reported proficiency with written Japanese and any dementia outcomes. Conclusions Proficiency with written Japanese does not appear to be protective for dementia. PMID:19593152

Independent and combined effects of physical activity and body mass index on the development of Type 2 Diabetes - a meta-analysis of 9 prospective cohort studies.

PubMed

Cloostermans, Laura; Wendel-Vos, Wanda; Doornbos, Gerda; Howard, Bethany; Craig, Cora Lynn; Kivimäki, Mika; Tabak, Adam G; Jefferis, Barbara J; Ronkainen, Kimmo; Brown, Wendy J; Picavet, Susan H S J; Ben-Shlomo, Yoav; Laukkanen, Jari Antero; Kauhanen, Jussi; Bemelmans, Wanda J E

2015-12-01

The aim of this harmonized meta-analysis was to examine the independent and combined effects of physical activity and BMI on the incidence of type 2 diabetes. Our systematic literature review in 2011 identified 127 potentially relevant prospective studies of which 9 fulfilled the inclusion criteria (total N = 117,878, 56.2 % female, mean age = 50.0 years, range = 25-65 years). Measures of baseline physical activity (low, intermediate, high), BMI-category [BMI < 18.4 (underweight), 18.5-24.9 (normal weight), 25.0-29.9 (overweight), 30+ (obese)] and incident type 2 diabetes were harmonized across studies. The associations between physical activity, BMI and incident type 2 diabetes were analyzed using Cox regression with a standardized analysis protocol including adjustments for age, gender, educational level, and smoking. Hazard ratios from individual studies were combined in a random-effects meta-analysis. Mean follow-up time was 9.1 years. A total of 11,237 incident type 2 diabetes cases were recorded. In mutually adjusted models, being overweight or obese (compared with normal weight) and having low physical activity (compared with high physical activity) were associated with an increased risk of incident type 2 diabetes (hazard ratios 2.33, 95 % CI 1.95-2.78; 6.10, 95 % CI: 4.63-8.04, and 1.23, 95 % CI: 1.09-1.39, respectively). Individuals who were both obese and had low physical activity had 7.4-fold (95 % CI 3.47-15.89) increased risk of type 2 diabetes compared with normal weight, high physically active participants. This harmonized meta-analysis shows the importance of maintaining a healthy weight and being physically active in diabetes prevention.

Dynamic contrast–enhanced magnetic resonance imaging in patients with pulmonary arterial hypertension

PubMed Central

Condliffe, Robin; Marshall, Helen; Elliot, Charlie; Kiely, David G.; Wild, Jim M.

2014-01-01

Abstract Dynamic contrast–enhanced (DCE) time-resolved magnetic resonance (MR) imaging is a technique whereby the passage of an intravenous contrast bolus can be tracked through the pulmonary vascular system. The aim of this study was to investigate the prognostic significance of DCE-MR pulmonary blood transit times in patients with pulmonary arterial hypertension (PAH). Seventy-nine patients diagnosed with PAH underwent pulmonary DCE imaging at 1.5 T using a time-resolved three-dimensional spoiled gradient echo sequence. The prognostic significance of two DCE parameters, full width at half maximum (FWHM) of the first-pass clearance curve and pulmonary transit time (PTT), along with demographic and invasive catheter measurements, was evaluated by univariate and bivariate Cox proportional hazards regression and Kaplan-Meier analysis. DCE-MR transit times were most closely correlated with cardiac index (CI) and pulmonary vascular resistance index (PVRI) and were both found to be accurate for detecting reduced CI (FWHM area under the curve [AUC] at receiver operating characteristic analysis = 0.91 and PTT AUC = 0.92, respectively) and for detecting elevated PVRI (FWHM AUC = 0.88 and PTT AUC = 0.84, respectively). During the follow-up period, 25 patients died. Patients with longer measurements of FWHM (P = 0.0014) and PTT (P = 0.004) were associated with poor outcome at Kaplan-Meier analysis, and both parameters were strong predictors of adverse outcome from Cox proportional hazards analysis (P = 0.013 and 0.010, respectively). At bivariate analysis, DCE measurements predicted mortality independent of age, gender, and World Health Organization functional class; however, invasive hemodynamic indexes CI, PVRI, and DCE measurements were not independent of one another. In conclusion, DCE-MR transit times predict mortality in patients with PAH and are closely associated with clinical gold standards CI and PVRI. PMID:25006422

Dynamic contrast-enhanced magnetic resonance imaging in patients with pulmonary arterial hypertension.

PubMed

Swift, Andrew J; Telfer, Adam; Rajaram, Smitha; Condliffe, Robin; Marshall, Helen; Capener, Dave; Hurdman, Judith; Elliot, Charlie; Kiely, David G; Wild, Jim M

2014-03-01

Dynamic contrast-enhanced (DCE) time-resolved magnetic resonance (MR) imaging is a technique whereby the passage of an intravenous contrast bolus can be tracked through the pulmonary vascular system. The aim of this study was to investigate the prognostic significance of DCE-MR pulmonary blood transit times in patients with pulmonary arterial hypertension (PAH). Seventy-nine patients diagnosed with PAH underwent pulmonary DCE imaging at 1.5 T using a time-resolved three-dimensional spoiled gradient echo sequence. The prognostic significance of two DCE parameters, full width at half maximum (FWHM) of the first-pass clearance curve and pulmonary transit time (PTT), along with demographic and invasive catheter measurements, was evaluated by univariate and bivariate Cox proportional hazards regression and Kaplan-Meier analysis. DCE-MR transit times were most closely correlated with cardiac index (CI) and pulmonary vascular resistance index (PVRI) and were both found to be accurate for detecting reduced CI (FWHM area under the curve [AUC] at receiver operating characteristic analysis = 0.91 and PTT AUC = 0.92, respectively) and for detecting elevated PVRI (FWHM AUC = 0.88 and PTT AUC = 0.84, respectively). During the follow-up period, 25 patients died. Patients with longer measurements of FWHM (P = 0.0014) and PTT (P = 0.004) were associated with poor outcome at Kaplan-Meier analysis, and both parameters were strong predictors of adverse outcome from Cox proportional hazards analysis (P = 0.013 and 0.010, respectively). At bivariate analysis, DCE measurements predicted mortality independent of age, gender, and World Health Organization functional class; however, invasive hemodynamic indexes CI, PVRI, and DCE measurements were not independent of one another. In conclusion, DCE-MR transit times predict mortality in patients with PAH and are closely associated with clinical gold standards CI and PVRI.

Hazardous Materials Routing Study Phase II: Analysis of Hazardous Materials Truck Routes in Proximity to the Dallas Central Business District

DOT National Transportation Integrated Search

1985-10-01

This report summarizes the findings from the second phase of a two-part analysis of hazardous materials truck routes in the Dallas-Fort Worth area. Phase II of this study analyzes the risk of transporting hazardous materials on freeways and arterial ...

21 CFR 123.6 - Hazard analysis and Hazard Analysis Critical Control Point (HACCP) plan.

Code of Federal Regulations, 2013 CFR

2013-04-01

... identified food safety hazards, including as appropriate: (i) Critical control points designed to control... control points designed to control food safety hazards introduced outside the processing plant environment... Control Point (HACCP) plan. 123.6 Section 123.6 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF...

21 CFR 123.6 - Hazard analysis and Hazard Analysis Critical Control Point (HACCP) plan.

Code of Federal Regulations, 2011 CFR

2011-04-01

... identified food safety hazards, including as appropriate: (i) Critical control points designed to control... control points designed to control food safety hazards introduced outside the processing plant environment... Control Point (HACCP) plan. 123.6 Section 123.6 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF...

21 CFR 123.6 - Hazard analysis and Hazard Analysis Critical Control Point (HACCP) plan.

Code of Federal Regulations, 2014 CFR

2014-04-01

... identified food safety hazards, including as appropriate: (i) Critical control points designed to control... control points designed to control food safety hazards introduced outside the processing plant environment... Control Point (HACCP) plan. 123.6 Section 123.6 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF...

Prognostic value of depression, anxiety, and anger in hospitalized cardiovascular disease patients for predicting adverse cardiac outcomes.

PubMed

Nakamura, Shunichi; Kato, Koji; Yoshida, Asuka; Fukuma, Nagaharu; Okumura, Yasuyuki; Ito, Hiroto; Mizuno, Kyoichi

2013-05-15

Although attention has recently been focused on the role of psychosocial factors in patients with cardiovascular disease (CVD), the factors that have the greatest influence on prognosis have not yet been elucidated. The aim of this study was to evaluate the effects of depression, anxiety, and anger on the prognosis of patients with CVD. Four hundred fourteen consecutive patients hospitalized with CVD were prospectively enrolled. Depression was evaluated using the Patient Health Questionnaire, anxiety using the Generalized Anxiety Disorder Questionnaire, and anger using the Spielberger Trait Anger Scale. Cox proportional-hazards regression was used to examine the individual effects of depression, anxiety, and anger on a combined primary end point of cardiac death or cardiac hospitalization and on a combined secondary end point of all-cause death or hospitalization during follow-up (median 14.2 months). Multivariate analysis showed that depression was a significant risk factor for cardiovascular hospitalization or death after adjusting for cardiac risk factors and other psychosocial factors (hazard ratio 2.62, p = 0.02), whereas anxiety was not significantly associated with cardiovascular hospitalization or death after adjustment (hazard ratio 2.35, p = 0.10). Anger was associated with a low rate of cardiovascular hospitalization or death (hazard ratio 0.34, p <0.01). In conclusion, depression in hospitalized patients with CVD is a stronger independent risk factor for adverse cardiac events than either anxiety or anger. Anger may help prevent adverse outcomes. Routine screening for depression should therefore be performed in patients with CVD, and the potential effects of anger in clinical practice should be reconsidered. Copyright © 2013 Elsevier Inc. All rights reserved.

Urinary incontinence, depression, and economic outcomes in a cohort of women between the ages of 54 and 65 years.

PubMed

Hung, Kristin J; Awtrey, Christopher S; Tsai, Alexander C

2014-04-01

To estimate the association between urinary incontinence (UI) and probable depression, work disability, and workforce exit. The analytic sample consisted of 4,511 women enrolled in the population-based Health and Retirement Study cohort. The analysis baseline was 1996, the year that questions about UI were added to the survey instrument, and at which time study participants were 54-65 years of age. Women were followed-up with biennial interviews until 2010-2011. Outcomes of interest were onset of probable depression, work disability, and workforce exit. Urinary incontinence was specified in different ways based on questions about experience and frequency of urine loss. We fit Cox proportional hazards regression models to the data, adjusting the estimates for baseline sociodemographic and health status variables previously found to confound the association between UI and the outcomes of interest. At baseline, 727 participants (survey-weighted prevalence, 16.6%; 95% confidence interval [CI] 15.4-18.0) reported any UI, of which 212 (survey-weighted prevalence, 29.2%; 95% CI 25.4-33.3) reported urine loss on more than 15 days in the past month; and 1,052 participants were categorized as having probable depression (survey-weighted prevalence, 21.6%; 95% CI 19.8-23.6). Urinary incontinence was associated with increased risks for probable depression (adjusted hazard ratio, 1.43; 95% CI 1.27-1.62) and work disability (adjusted hazard ratio, 1.21; 95% CI 1.01-1.45), but not workforce exit (adjusted hazard ratio, 1.06; 95% CI 0.93-1.21). In a population-based cohort of women between ages 54 and 65 years, UI was associated with increased risks for probable depression and work disability. Improved diagnosis and management of UI may yield significant economic and psychosocial benefits.

Sleep disorders and an increased risk of Parkinson's disease in individuals with non-apnea sleep disorders: a population-based cohort study.

PubMed

Hsiao, Yi-Han; Chen, Yung-Tai; Tseng, Ching-Ming; Wu, Li-An; Perng, Diahn-Warng; Chen, Yuh-Min; Chen, Tzeng-Ji; Chang, Shi-Chuan; Chou, Kun-Ta

2017-10-01

Sleep disorders are common non-motor symptoms in patients with Parkinson's disease. Our study aims to explore the relationship between non-apnea sleep disorders and future Parkinson's disease. This is a cohort study using a nationwide database. The participants were recruited from the Taiwan National Health Insurance Research Database between 2000 and 2003. A total of 91 273 adult patients who had non-apnea sleep disorders without pre-existing Parkinson's disease were enrolled. An age-, gender-, income-, urbanization- and Charlson comorbidity index score-matched control cohort consisting of 91 273 participants was selected for comparison. The two cohorts were followed for the occurrence of Parkinson's disease, death or until the end of 2010, whichever came first. The Kaplan-Meier analyses revealed patients with non-apnea sleep disorders tended to develop Parkinson's disease (log-rank test, P < 0.001). After a multivariate adjustment in a Cox regression model, non-apnea sleep disorders was an independent risk factor for the development of Parkinson's disease [crude hazard ratio: 1.63, 95% confidence interval (CI): 1.54-1.73, P < 0.001; adjusted hazard ratio: 1.18, 95% CI: 1.11-1.26, P < 0.001]. In the subgroup analysis, patients with chronic insomnia (lasting more than 3 months) had the greatest risk (crude hazard ratio: 2.91, 95% CI: 2.59-3.26, P < 0.001; adjusted hazard ratio: 1.37, 95% CI: 1.21-1.55, P < 0.001). In conclusion, this study revealed that non-apnea sleep disorders, especially chronic insomnia, are associated with a higher risk for future Parkinson's disease. © 2017 European Sleep Research Society.