Sample records for multivariate longitudinal analyses

  1. Concurrent and Longitudinal Effects of Morphological Awareness on Reading Comprehension among Chinese-Speaking Children

    ERIC Educational Resources Information Center

    Zhang, Haomin

    2016-01-01

    This study explored the concurrent and longitudinal effects of morphological awareness on the development of reading comprehension among Chinese-speaking children (N = 123, mean[subscript age] = 8.1 at Time 2). Drawing upon multivariate analyses, the study found that morphological awareness and lexical inferencing ability were intertwined together…

  2. Parenting Style and Behavior as Longitudinal Predictors of Adolescent Alcohol Use.

    PubMed

    Minaie, Matin Ghayour; Hui, Ka Kit; Leung, Rachel K; Toumbourou, John W; King, Ross M

    2015-09-01

    Adolescent alcohol use is a serious problem in Australia and other nations. Longitudinal data on family predictors are valuable to guide parental education efforts. The present study tested Baumrind's proposal that parenting styles are direct predictors of adolescent alcohol use. Latent class modeling was used to investigate adolescent perceptions of parenting styles and multivariate regression to examine their predictive effect on the development of adolescent alcohol use. The data set comprised 2,081 secondary school students (55.9% female) from metropolitan Melbourne, Australia, who completed three waves of annual longitudinal data starting in 2004. Baumrind's parenting styles were significant predictors in unadjusted analyses, but these effects were not maintained in multivariate models that also included parenting behavior dimensions. Family influences on the development of adolescent alcohol use appear to operate more directly through specific family management behaviors rather than through more global parenting styles.

  3. Religion and body weight: a review of quantitative studies.

    PubMed

    Yeary, Karen Hye-Cheon Kim; Sobal, Jeffery; Wethington, Elaine

    2017-10-01

    Increasing interest in relationships between religion and health has encouraged research about religion and body weight, which has produced mixed findings. We systematically searched 11 bibliographic databases for quantitative studies of religion and weight, locating and coding 85 studies. We conducted a systematic review, analysing descriptive characteristics of the studies as well as relevant religion-body weight associations related to study characteristics. We summarized findings for two categories of religion variables: religious affiliation and religiosity. For religious affiliation, we found evidence for significant associations with body weight in both cross-sectional and longitudinal studies. In particular, Seventh-Day Adventists had lower body weight than other denominations in cross-sectional analyses. For religiosity, significant associations occurred between greater religiosity and higher body weight in both cross-sectional and longitudinal studies. In particular, greater religiosity was significantly associated with higher body weight in bivariate analyses but less so in multivariate analyses. A greater proportion of studies that used a representative sample, longitudinal analyses, and samples with only men reported significant associations between religiosity and weight. Evidence in seven studies suggested that health behaviours and psychosocial factors mediate religion-weight relationships. More longitudinal studies and analyses of mediators are needed to provide stronger evidence and further elucidate religion-weight relationships. © 2017 World Obesity Federation.

  4. A multivariate distance-based analytic framework for microbial interdependence association test in longitudinal study.

    PubMed

    Zhang, Yilong; Han, Sung Won; Cox, Laura M; Li, Huilin

    2017-12-01

    Human microbiome is the collection of microbes living in and on the various parts of our body. The microbes living on our body in nature do not live alone. They act as integrated microbial community with massive competing and cooperating and contribute to our human health in a very important way. Most current analyses focus on examining microbial differences at a single time point, which do not adequately capture the dynamic nature of the microbiome data. With the advent of high-throughput sequencing and analytical tools, we are able to probe the interdependent relationship among microbial species through longitudinal study. Here, we propose a multivariate distance-based test to evaluate the association between key phenotypic variables and microbial interdependence utilizing the repeatedly measured microbiome data. Extensive simulations were performed to evaluate the validity and efficiency of the proposed method. We also demonstrate the utility of the proposed test using a well-designed longitudinal murine experiment and a longitudinal human study. The proposed methodology has been implemented in the freely distributed open-source R package and Python code. © 2017 WILEY PERIODICALS, INC.

  5. Teenage Childbearing among Youth Born to Teenage Mothers

    ERIC Educational Resources Information Center

    Wildsmith, Elizabeth; Manlove, Jennifer; Jekielek, Susan; Moore, Kristin Anderson; Mincieli, Lisa

    2012-01-01

    Using data from the National Longitudinal Survey of Youth, this article examined how early maternal characteristics, an adolescent's family environment, and the adolescent's own attitudes and behaviors were associated with the odds of a nonmarital teenage birth among youth born to teenage mothers. Multivariate analyses indicated that these domains…

  6. Effects of Student Characteristics on Grades in Compulsory School

    ERIC Educational Resources Information Center

    Lekholm, Alli Klapp; Cliffordson, Christina

    2009-01-01

    The purpose of the study was to investigate how different student characteristics such as gender influence grades. In order to answer these questions, multivariate techniques were used. The data derive from The Gothenburg Educational Longitudinal Database (GOLD), and the subjects were 99,070 ninth-grade students born in 1987. The analyses were…

  7. Employment, Work Conditions, and the Home Environment in Single-Mother Families

    ERIC Educational Resources Information Center

    Lleras, Christy

    2008-01-01

    This study investigates the impact of employment status and work conditions on the quality of the home environment provided by single mothers of preschool-age children. Multivariate analyses were conducted using data from the National Longitudinal Survey of Youth. The results indicate that employment status is not a significant predictor of the…

  8. Controlled pattern imputation for sensitivity analysis of longitudinal binary and ordinal outcomes with nonignorable dropout.

    PubMed

    Tang, Yongqiang

    2018-04-30

    The controlled imputation method refers to a class of pattern mixture models that have been commonly used as sensitivity analyses of longitudinal clinical trials with nonignorable dropout in recent years. These pattern mixture models assume that participants in the experimental arm after dropout have similar response profiles to the control participants or have worse outcomes than otherwise similar participants who remain on the experimental treatment. In spite of its popularity, the controlled imputation has not been formally developed for longitudinal binary and ordinal outcomes partially due to the lack of a natural multivariate distribution for such endpoints. In this paper, we propose 2 approaches for implementing the controlled imputation for binary and ordinal data based respectively on the sequential logistic regression and the multivariate probit model. Efficient Markov chain Monte Carlo algorithms are developed for missing data imputation by using the monotone data augmentation technique for the sequential logistic regression and a parameter-expanded monotone data augmentation scheme for the multivariate probit model. We assess the performance of the proposed procedures by simulation and the analysis of a schizophrenia clinical trial and compare them with the fully conditional specification, last observation carried forward, and baseline observation carried forward imputation methods. Copyright © 2018 John Wiley & Sons, Ltd.

  9. Heritability of somatotype components from early adolescence into young adulthood: a multivariate analysis on a longitudinal twin study.

    PubMed

    Peeters, M W; Thomis, M A; Claessens, A L; Loos, R J F; Maes, H H M; Lysens, R; Vanden Eynde, B; Vlietinck, R; Beunen, G

    2003-01-01

    Several studies with different designs have attempted to estimate the heritability of somatotype components. However they often ignore the covariation between the three components as well as possible sex and age effects. Shared environmental factors are not always controlled for. This study explores the pattern of genetic and environmental determination of the variation in Heath-Carter somatotype components from early adolescence into young adulthood. Data from the Leuven Longitudinal Twin Study, a longitudinal sample of Belgian same-aged twins followed from 10 to 18 years (n = 105 pairs, equally divided over five zygosity groups), is entered into a multivariate path analysis. Thus the covariation between the somatotype components is taken into account, gender heterogeneity can be tested, common environmental influences can be distinguished from genetic effects and age effects are controlled for. Heritability estimates from 10 to 18 years range from 0.21 to 0.88, 0.46 to 0.76 and 0.16 to 0.73 for endomorphy, mesomorphy and ectomorphy in boys. In girls, heritability estimates range from 0.76 to 0.89, 0.36 to 0.57 and 0.57 to 0.76 for the respective somatotype components. Sex differences are significant from 14 years onwards. More than half of the variance in all somatotype components for both sexes at all time points is explained by factors the three components have in common. The finding of substantial genetic influence on the variability of somatotype components is further supported. The need to consider somatotype as a whole is stressed as well as the need for sex- and perhaps age-specific analyses. Further multivariate analyses are needed to confirm the present findings.

  10. Depression among Couples in the United States in the Context of Intimate Partner Violence

    ERIC Educational Resources Information Center

    Vaeth, Patrice A. C.; Ramisetty-Mikler, Suhasini; Caetano, Raul

    2010-01-01

    This paper examines the relationship between intimate partner violence and depression. A multicluster random household sample of U.S. couples was interviewed as part of a five-year national longitudinal study (response rate = 72%). Depression was assessed with the CES-D. The multivariate analyses for men showed that the odds of depression did not…

  11. Multivariate analysis of longitudinal rates of change.

    PubMed

    Bryan, Matthew; Heagerty, Patrick J

    2016-12-10

    Longitudinal data allow direct comparison of the change in patient outcomes associated with treatment or exposure. Frequently, several longitudinal measures are collected that either reflect a common underlying health status, or characterize processes that are influenced in a similar way by covariates such as exposure or demographic characteristics. Statistical methods that can combine multivariate response variables into common measures of covariate effects have been proposed in the literature. Current methods for characterizing the relationship between covariates and the rate of change in multivariate outcomes are limited to select models. For example, 'accelerated time' methods have been developed which assume that covariates rescale time in longitudinal models for disease progression. In this manuscript, we detail an alternative multivariate model formulation that directly structures longitudinal rates of change and that permits a common covariate effect across multiple outcomes. We detail maximum likelihood estimation for a multivariate longitudinal mixed model. We show via asymptotic calculations the potential gain in power that may be achieved with a common analysis of multiple outcomes. We apply the proposed methods to the analysis of a trivariate outcome for infant growth and compare rates of change for HIV infected and uninfected infants. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  12. Predicting the multi-domain progression of Parkinson's disease: a Bayesian multivariate generalized linear mixed-effect model.

    PubMed

    Wang, Ming; Li, Zheng; Lee, Eun Young; Lewis, Mechelle M; Zhang, Lijun; Sterling, Nicholas W; Wagner, Daymond; Eslinger, Paul; Du, Guangwei; Huang, Xuemei

    2017-09-25

    It is challenging for current statistical models to predict clinical progression of Parkinson's disease (PD) because of the involvement of multi-domains and longitudinal data. Past univariate longitudinal or multivariate analyses from cross-sectional trials have limited power to predict individual outcomes or a single moment. The multivariate generalized linear mixed-effect model (GLMM) under the Bayesian framework was proposed to study multi-domain longitudinal outcomes obtained at baseline, 18-, and 36-month. The outcomes included motor, non-motor, and postural instability scores from the MDS-UPDRS, and demographic and standardized clinical data were utilized as covariates. The dynamic prediction was performed for both internal and external subjects using the samples from the posterior distributions of the parameter estimates and random effects, and also the predictive accuracy was evaluated based on the root of mean square error (RMSE), absolute bias (AB) and the area under the receiver operating characteristic (ROC) curve. First, our prediction model identified clinical data that were differentially associated with motor, non-motor, and postural stability scores. Second, the predictive accuracy of our model for the training data was assessed, and improved prediction was gained in particularly for non-motor (RMSE and AB: 2.89 and 2.20) compared to univariate analysis (RMSE and AB: 3.04 and 2.35). Third, the individual-level predictions of longitudinal trajectories for the testing data were performed, with ~80% observed values falling within the 95% credible intervals. Multivariate general mixed models hold promise to predict clinical progression of individual outcomes in PD. The data was obtained from Dr. Xuemei Huang's NIH grant R01 NS060722 , part of NINDS PD Biomarker Program (PDBP). All data was entered within 24 h of collection to the Data Management Repository (DMR), which is publically available ( https://pdbp.ninds.nih.gov/data-management ).

  13. Explicating the Conditions Under Which Multilevel Multiple Imputation Mitigates Bias Resulting from Random Coefficient-Dependent Missing Longitudinal Data.

    PubMed

    Gottfredson, Nisha C; Sterba, Sonya K; Jackson, Kristina M

    2017-01-01

    Random coefficient-dependent (RCD) missingness is a non-ignorable mechanism through which missing data can arise in longitudinal designs. RCD, for which we cannot test, is a problematic form of missingness that occurs if subject-specific random effects correlate with propensity for missingness or dropout. Particularly when covariate missingness is a problem, investigators typically handle missing longitudinal data by using single-level multiple imputation procedures implemented with long-format data, which ignores within-person dependency entirely, or implemented with wide-format (i.e., multivariate) data, which ignores some aspects of within-person dependency. When either of these standard approaches to handling missing longitudinal data is used, RCD missingness leads to parameter bias and incorrect inference. We explain why multilevel multiple imputation (MMI) should alleviate bias induced by a RCD missing data mechanism under conditions that contribute to stronger determinacy of random coefficients. We evaluate our hypothesis with a simulation study. Three design factors are considered: intraclass correlation (ICC; ranging from .25 to .75), number of waves (ranging from 4 to 8), and percent of missing data (ranging from 20 to 50%). We find that MMI greatly outperforms the single-level wide-format (multivariate) method for imputation under a RCD mechanism. For the MMI analyses, bias was most alleviated when the ICC is high, there were more waves of data, and when there was less missing data. Practical recommendations for handling longitudinal missing data are suggested.

  14. Multivariate Analysis of Longitudinal Rates of Change

    PubMed Central

    Bryan, Matthew; Heagerty, Patrick J.

    2016-01-01

    Longitudinal data allow direct comparison of the change in patient outcomes associated with treatment or exposure. Frequently, several longitudinal measures are collected that either reflect a common underlying health status, or characterize processes that are influenced in a similar way by covariates such as exposure or demographic characteristics. Statistical methods that can combine multivariate response variables into common measures of covariate effects have been proposed by Roy and Lin [1]; Proust-Lima, Letenneur and Jacqmin-Gadda [2]; and Gray and Brookmeyer [3] among others. Current methods for characterizing the relationship between covariates and the rate of change in multivariate outcomes are limited to select models. For example, Gray and Brookmeyer [3] introduce an “accelerated time” method which assumes that covariates rescale time in longitudinal models for disease progression. In this manuscript we detail an alternative multivariate model formulation that directly structures longitudinal rates of change, and that permits a common covariate effect across multiple outcomes. We detail maximum likelihood estimation for a multivariate longitudinal mixed model. We show via asymptotic calculations the potential gain in power that may be achieved with a common analysis of multiple outcomes. We apply the proposed methods to the analysis of a trivariate outcome for infant growth and compare rates of change for HIV infected and uninfected infants. PMID:27417129

  15. Persistent Deterioration of Functioning (PDF) and change in well-being in older persons.

    PubMed

    Jonker, Angèle A; Comijs, Hannie C; Knipscheer, Kees C; Deeg, Dorly J

    2008-10-01

    It is often assumed that aging is accompanied by diverse and constant functional and cognitive decline, and it is therefore surprising that the well-being of older persons does not appear to decline in the same way. This study investigates longitudinally whether well-being in older persons changes due to Persistent Deterioration of Functioning (PDF). Data were collected in the context of the Longitudinal Aging Study Amsterdam (LASA). Conditions of PDF are persistent decline in cognitive functioning, physical functioning and increase in chronic diseases. Measurements of well-being included life satisfaction, positive affect, and valuation of life. T-tests were used to analyse mean difference scores for well-being, and univariate and multivariate regression analyses were performed to examine changes in three well-being outcomes in relation to PDF. Cross-sectional analyses showed significant differences and associations between the two PDF subgroups and non- PDF for well-being at T3. In longitudinal analyses, we found significant decreases in and associations with wellbeing over time in respondents fulfilling one PDF condition (mild PDF). For respondents fulfilling two or more PDF conditions (severe PDF), longitudinally no significant associations were found. Cognitive aspects of well-being (life satisfaction and valuation of life) and the affective element (positive affect) of well-being appear to be influenced negatively by mild PDF, whereas well-being does not seem to be diminished in persons with more severe PDF. This may be due to the ability to accept finally the inevitable situation of severe PDF.

  16. Prospective inverse associations of sex hormone concentrations in men with biomarkers of inflammation and oxidative stress.

    PubMed

    Haring, Robin; Baumeister, Sebastian E; Völzke, Henry; Dörr, Marcus; Kocher, Thomas; Nauck, Matthias; Wallaschofski, Henri

    2012-01-01

    The suggested associations between sex hormone concentrations and inflammatory biomarkers in men originate from cross-sectional studies and small-scale clinical trials. But prior studies have not investigated longitudinal associations. Overall, 1344 men aged 20-79 years from the population-based cohort Study of Health in Pomerania were followed up for 5.0 (median) years. We used multivariable regression models to analyze cross-sectional and longitudinal associations of serum sex hormone concentrations (total testosterone [TT], sex hormone-binding globulin [SHBG], calculated free testosterone [free T], and dehydroepiandrosterone sulfate [DHEAS]) with biomarkers of inflammation (fibrinogen, high-sensitive C-reactive protein [hsCRP], and white blood cell count [WBC]) and oxidative stress (γ-glutamyl transferase [GGT]) using ordinary least square regression and generalized estimating equation models, respectively. Cross-sectional models revealed borderline associations of sex hormone concentrations with hsCRP, WBC, and GGT levels that were not retained after multivariable adjustment. Longitudinal multivariable analyses revealed an inverse association of baseline TT, free T, and DHEAS concentrations with change in fibrinogen levels (per SD decrement in TT, 0.25 [95% confidence interval, 0.04-0.45]; in free T, 0.30 [0.09-0.51]; and in DHEAS, 0.23 [0.11-0.36]). Furthermore, baseline DHEAS concentrations were inversely associated with change in WBC levels (per SD decrement, 0.53 [0.24-0.82]). Baseline TT, SHBG, free T, and DHEAS concentrations were also inversely associated with change in GGT after multivariable adjustment. The present study is the first to demonstrate prospective inverse associations between sex hormone concentrations and markers of inflammation and oxidative stress in men. Additional studies are warranted to elucidate potential mechanisms underlying the revealed associations.

  17. Multivariate Longitudinal Analysis with Bivariate Correlation Test

    PubMed Central

    Adjakossa, Eric Houngla; Sadissou, Ibrahim; Hounkonnou, Mahouton Norbert; Nuel, Gregory

    2016-01-01

    In the context of multivariate multilevel data analysis, this paper focuses on the multivariate linear mixed-effects model, including all the correlations between the random effects when the dimensional residual terms are assumed uncorrelated. Using the EM algorithm, we suggest more general expressions of the model’s parameters estimators. These estimators can be used in the framework of the multivariate longitudinal data analysis as well as in the more general context of the analysis of multivariate multilevel data. By using a likelihood ratio test, we test the significance of the correlations between the random effects of two dependent variables of the model, in order to investigate whether or not it is useful to model these dependent variables jointly. Simulation studies are done to assess both the parameter recovery performance of the EM estimators and the power of the test. Using two empirical data sets which are of longitudinal multivariate type and multivariate multilevel type, respectively, the usefulness of the test is illustrated. PMID:27537692

  18. Multivariate Longitudinal Analysis with Bivariate Correlation Test.

    PubMed

    Adjakossa, Eric Houngla; Sadissou, Ibrahim; Hounkonnou, Mahouton Norbert; Nuel, Gregory

    2016-01-01

    In the context of multivariate multilevel data analysis, this paper focuses on the multivariate linear mixed-effects model, including all the correlations between the random effects when the dimensional residual terms are assumed uncorrelated. Using the EM algorithm, we suggest more general expressions of the model's parameters estimators. These estimators can be used in the framework of the multivariate longitudinal data analysis as well as in the more general context of the analysis of multivariate multilevel data. By using a likelihood ratio test, we test the significance of the correlations between the random effects of two dependent variables of the model, in order to investigate whether or not it is useful to model these dependent variables jointly. Simulation studies are done to assess both the parameter recovery performance of the EM estimators and the power of the test. Using two empirical data sets which are of longitudinal multivariate type and multivariate multilevel type, respectively, the usefulness of the test is illustrated.

  19. The Relationships between Negative Life Events, Perceived Support in the School Environment and Depressive Symptoms among Norwegian Senior High School Students: A Prospective Study

    ERIC Educational Resources Information Center

    Murberg, Terje A.; Bru, Edvin

    2009-01-01

    The present study prospectively explored the main and interactive effect of negative life events and social support from teachers and classroom peers on depressive symptoms in a sample of 198 (111 females, 87 males) students in a Norwegian senior high school. In the longitudinal multivariate analyses, self-reported depressive symptom levels at…

  20. Criminal-justice and school sanctions against nonheterosexual youth: a national longitudinal study.

    PubMed

    Himmelstein, Kathryn E W; Brückner, Hannah

    2011-01-01

    Nonheterosexual adolescents are vulnerable to health risks including addiction, bullying, and familial abuse. We examined whether they also suffer disproportionate school and criminal-justice sanctions. The National Longitudinal Study of Adolescent Health followed a nationally representative sample of adolescents who were in grades 7 through 12 in 1994-1995. Data from the 1994-1995 survey and the 2001-2002 follow-up were analyzed. Three measures were used to assess nonheterosexuality: same-sex attraction, same-sex romantic relationships, and lesbian, gay, or bisexual (LGB) self-identification. Six outcomes were assessed: school expulsion; police stops; juvenile arrest; juvenile conviction; adult arrest; and adult conviction. Multivariate analyses controlled for adolescents' sociodemographics and behaviors, including illegal conduct. Nonheterosexuality consistently predicted a higher risk for sanctions. For example, in multivariate analyses, nonheterosexual adolescents had greater odds of being stopped by the police (odds ratio: 1.38 [P < .0001] for same-sex attraction and 1.53 [P < .0001] for LGB self-identification). Similar trends were observed for school expulsion, juvenile arrest and conviction, and adult conviction. Nonheterosexual girls were at particularly high risk. Nonheterosexual youth suffer disproportionate educational and criminal-justice punishments that are not explained by greater engagement in illegal or transgressive behaviors. Understanding and addressing these disparities might reduce school expulsions, arrests, and incarceration and their dire social and health consequences.

  1. Triglyceride and glucose (TyG) index as a predictor of incident hypertension: a 9-year longitudinal population-based study.

    PubMed

    Zheng, Rongjiong; Mao, Yushan

    2017-09-13

    Hypertension and the triglyceride and glucose index both have been associated with insulin resistance; however, the longitudinal association remains unclear. This study was designed to investigate the longitudinal association between the triglyceride and glucose index and incident hypertension among the Chinese population. We studied 4686 subjects (3177 males and 1509 females) and followed up for 9 years. The subjects were divided into four groups based on the triglyceride and glucose index. Univariate and multivariate Cox regression models were used to analyse the risk factors of hypertension. After 9 years of follow-up, 2047 subjects developed hypertension. The overall 9-year cumulative incidence of hypertension was 43.7%, ranging from 28.5% in quartile 1 to 36.9% in quartile 2, 49.2% in quartile 3 and 59.8% in quartile 4 (p for trend < 0.001). Cox regression analyses indicated that higher triglyceride and glucose index was associated with an increased risk of subsequent incident hypertension. The triglyceride and glucose index can predict the incident hypertension among the Chinese population.

  2. An Examination of the Association between Seeing Smoking in Films and Tobacco Use in Young Adults in the West of Scotland: Cross-Sectional Study

    ERIC Educational Resources Information Center

    Hunt, Kate; Sweeting, Helen; Sargent, James; Lewars, Heather; Cin, Sonya Dal; Worth, Keilah

    2009-01-01

    The objective is to examine the association between the amount of smoking seen in films and current smoking in young adults living in the west of Scotland in the UK. Cross-sectional analyses (using multivariable logistic regression) of data collected at age 19 (2002-04) from a longitudinal cohort originally surveyed at age 11 (1994-95) were…

  3. Clinical and dermoscopic clues to differentiate pigmented nail bands: an International Dermoscopy Society study.

    PubMed

    Benati, E; Ribero, S; Longo, C; Piana, S; Puig, S; Carrera, C; Cicero, F; Kittler, H; Deinlein, T; Zalaudek, I; Stolz, W; Scope, A; Pellacani, G; Moscarella, E; Piraccini, B M; Starace, M; Argenziano, G

    2017-04-01

    Longitudinal melanonychia might be difficult to differentiate and the use of dermoscopy can be useful for the preoperative evaluation and management decision. The aim of our study was to investigate clinical and dermoscopic criteria of acquired longitudinal melanonychia in adults to identify the best predictors of melanoma using a multivariate analysis and to explore eventual new dermoscopic criteria for nail melanoma diagnosis. In this retrospective observational study, 82 histopathologically diagnosed, acquired nail pigmented bands were collected and examined. All variables were included in the analysis and examined as possible predictors of nail melanoma. Both univariate and multivariable analyses have been performed. Among 82 cases, 25 were diagnosed as nail melanoma and 57 as benign lesions (including 32 melanocytic nevi and 25 benign melanocytic hyperplasia). Melanoma cases were significantly associated with a width of the pigmented band higher than 2/3 of the nail plate, grey and black colours, irregularly pigmented lines, Hutchinson and micro-Hutchinson signs, and nail dystrophy. Granular pigmentation, a newly defined dermoscopic criterion, was found in 40% of melanomas and only in 3.51% of benign lesions. Dermoscopic examination of longitudinal melanonychia provides useful information that could help clinicians to improve melanoma recognition. © 2016 European Academy of Dermatology and Venereology.

  4. Influence assessment in censored mixed-effects models using the multivariate Student’s-t distribution

    PubMed Central

    Matos, Larissa A.; Bandyopadhyay, Dipankar; Castro, Luis M.; Lachos, Victor H.

    2015-01-01

    In biomedical studies on HIV RNA dynamics, viral loads generate repeated measures that are often subjected to upper and lower detection limits, and hence these responses are either left- or right-censored. Linear and non-linear mixed-effects censored (LMEC/NLMEC) models are routinely used to analyse these longitudinal data, with normality assumptions for the random effects and residual errors. However, the derived inference may not be robust when these underlying normality assumptions are questionable, especially the presence of outliers and thick-tails. Motivated by this, Matos et al. (2013b) recently proposed an exact EM-type algorithm for LMEC/NLMEC models using a multivariate Student’s-t distribution, with closed-form expressions at the E-step. In this paper, we develop influence diagnostics for LMEC/NLMEC models using the multivariate Student’s-t density, based on the conditional expectation of the complete data log-likelihood. This partially eliminates the complexity associated with the approach of Cook (1977, 1986) for censored mixed-effects models. The new methodology is illustrated via an application to a longitudinal HIV dataset. In addition, a simulation study explores the accuracy of the proposed measures in detecting possible influential observations for heavy-tailed censored data under different perturbation and censoring schemes. PMID:26190871

  5. Multivariate longitudinal data analysis with censored and intermittent missing responses.

    PubMed

    Lin, Tsung-I; Lachos, Victor H; Wang, Wan-Lun

    2018-05-08

    The multivariate linear mixed model (MLMM) has emerged as an important analytical tool for longitudinal data with multiple outcomes. However, the analysis of multivariate longitudinal data could be complicated by the presence of censored measurements because of a detection limit of the assay in combination with unavoidable missing values arising when subjects miss some of their scheduled visits intermittently. This paper presents a generalization of the MLMM approach, called the MLMM-CM, for a joint analysis of the multivariate longitudinal data with censored and intermittent missing responses. A computationally feasible expectation maximization-based procedure is developed to carry out maximum likelihood estimation within the MLMM-CM framework. Moreover, the asymptotic standard errors of fixed effects are explicitly obtained via the information-based method. We illustrate our methodology by using simulated data and a case study from an AIDS clinical trial. Experimental results reveal that the proposed method is able to provide more satisfactory performance as compared with the traditional MLMM approach. Copyright © 2018 John Wiley & Sons, Ltd.

  6. Attrition analysed in five waves of a longitudinal yearly survey of smokers: findings from the ITC Netherlands survey.

    PubMed

    Zethof, Dennis; Nagelhout, Gera E; de Rooij, Mark; Driezen, Pete; Fong, Geoffrey T; van den Putte, Bas; Hummel, Karin; de Vries, Hein; Thompson, Mary E; Willemsen, Marc C

    2016-08-01

    Attrition bias can affect the external validity of findings. This article analyses attrition bias and assesses the effectiveness of replenishment samples on demographic and smoking-related characteristics for the International Tobacco Control Netherlands Survey, a longitudinal survey among smokers. Attrition analyses were conducted for the first five survey waves (2008-12). We assessed, including and excluding replenishment samples, whether the demographic composition of the samples changed between the first and fifth waves. Replenishment samples were tailored to ensure the sample remained representative of the smoking population. We also constructed a multivariable survival model of attrition that included all five waves with replenishment samples. Of the original 1820 respondents recruited in 2008, 46% participated again in 2012. Demographic differences between waves due to attrition were generally small and replenishment samples tended to minimize them further. The multivariable survival analysis revealed that only two of the 10 variables analysed were significant predictors of attrition: a weak effect for gender (men dropped out more often) and weak to moderate effects for age (respondents aged 15-24 years dropped out more than aged 25-39 years, who dropped out more than those aged 40+ years). Weak to moderate attrition effects were found for men and younger age groups. This information could be used to minimize respondent attrition. Our findings suggest that sampling weights and tailored replenishment samples can effectively compensate for attrition effects. This is already being done for the International Tobacco Control Netherlands Survey, including the categories that significantly predicted attrition in this study. © The Author 2016. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

  7. Association of left ventricular longitudinal and circumferential systolic dysfunction with diastolic function in hypertension: a nonlinear analysis focused on the interplay with left ventricular geometry.

    PubMed

    Ballo, Piercarlo; Nistri, Stefano; Cameli, Matteo; Papesso, Barbara; Dini, Frank Lloyd; Galderisi, Maurizio; Zuppiroli, Alfredo; Mondillo, Sergio

    2014-02-01

    The relationships of left ventricular (LV) longitudinal and circumferential systolic dysfunction with diastolic performance in hypertensive patients have never been compared. In 532 asymptomatic hypertensive patients, circumferential function was assessed with the use of midwall fractional shortening (mFS) and stress-corrected mFS (SCmFS), whereas longitudinal function was assessed with the use of left atrioventricular plane displacement (AVPD) and systolic mitral annulus velocity (s'). Early diastolic annular velocity (e') and the E/e' ratio were measured. Global longitudinal and circumferential strain were determined in a subset of 210 patients. e' was linearly related to all systolic indexes (AVPD: R = 0.40; s': R = 0.39; mFS: R = 0.16; SCmFS: R = 0.17; all P < .0001), but the correlations were stronger with longitudinal indexes than with circumferential ones (P < .0001). E/e' was nonlinearly related to AVPD (R = -0.49; P < .0001) and s' (R = -0.34; P < .0001) and showed no relationship with mFS and SCmFS. Longitudinal indexes were superior to circumferential ones in predicting e' <8 cm/s, E/e' <8, and E/e' ≥13. The effect of LV geometry on LV diastolic function was evident among patients with preserved systolic longitudinal function, but was blunted among patients with impaired longitudinal function. In multivariable analyses, only longitudinal indexes remained associated with e' and E/e'. Analyses using strains provided similar results. In asymptomatic hypertensive subjects, LV diastolic performance is independently associated with longitudinal systolic dysfunction, but not with circumferential systolic dysfunction. Subtle longitudinal systolic impairment plays a role in mediating the effect of LV geometry on diastolic performance. These findings may support the need of critically revising the concept of isolated diastolic dysfunction in these patients. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Acute suicidal ideation in middle-aged adults from Brazil. Results from the baseline data of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

    PubMed

    Brunoni, André R; Nunes, Maria A; Lotufo, Paulo A; Benseñor, Isabela M

    2015-02-28

    Suicidal ideation represents an important burden worldwide. However, little is known about it in low-/middle-income countries. We investigated this issue in a large cross-sectional of Brazilian civil servants (ELSA-Brasil, the Brazilian Health Longitudinal Study, n=15,105). Logistic univariate and multivariate analyses were performed to evaluate the strength of association (odds ratio, OR) between clinical and sociodemographic variables with acute life-weariness (tiredness of life) and suicidal thoughts. The presence of major depressive disorder (MDD), common mental disorders (CMDs), stressful life-events (SLEs) and poor self-perceived physical health was also collected. MDD and CMDs were strongly associated with suicidal ideation in univariate and multivariate analyses. For life-weariness thoughts, a modest, consistent association was found for female gender, being single, non-White ethnicity and poor education. SLEs and poor self-perceived physical health were also associated with suicidal ideation. Espiritism-Kardecism, but not other religions or Atheism/Agnosticism, was associated with lower rates of life-weariness and suicidal thoughts. To conclude, suicidal ideation does not differ in Brazil compared to developed countries, being primarily associated with psychiatric disorders and, to a lesser but significant extent, to social disadvantage, SLEs, poor self-perceived health and being single. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  9. Insulin Sensitivity Measured With Euglycemic Clamp Is Independently Associated With Glomerular Filtration Rate in a Community-Based Cohort

    PubMed Central

    Nerpin, Elisabet; Risérus, Ulf; Ingelsson, Erik; Sundström, Johan; Jobs, Magnus; Larsson, Anders; Basu, Samar; Ärnlöv, Johan

    2008-01-01

    OBJECTIVE—To investigate the association between insulin sensitivity and glomerular filtration rate (GFR) in the community, with prespecified subgroup analyses in normoglycemic individuals with normal GFR. RESEARCH DESIGN AND METHODS—We investigated the cross-sectional association between insulin sensitivity (M/I, assessed using euglycemic clamp) and cystatin C–based GFR in a community-based cohort of elderly men (Uppsala Longitudinal Study of Adult Men [ULSAM], n = 1,070). We also investigated whether insulin sensitivity predicted the incidence of renal dysfunction at a follow-up examination after 7 years. RESULTS—Insulin sensitivity was directly related to GFR (multivariable-adjusted regression coefficient for 1-unit higher M/I 1.19 [95% CI 0.69–1.68]; P < 0.001) after adjusting for age, glucometabolic variables (fasting plasma glucose, fasting plasma insulin, and 2-h glucose after an oral glucose tolerance test), cardiovascular risk factors (hypertension, dyslipidemia, and smoking), and lifestyle factors (BMI, physical activity, and consumption of tea, coffee, and alcohol). The positive multivariable-adjusted association between insulin sensitivity and GFR also remained statistically significant in participants with normal fasting plasma glucose, normal glucose tolerance, and normal GFR (n = 443; P < 0.02). In longitudinal analyses, higher insulin sensitivity at baseline was associated with lower risk of impaired renal function (GFR <50 ml/min per 1.73 m2) during follow-up independently of glucometabolic variables (multivariable-adjusted odds ratio for 1-unit higher of M/I 0.58 [95% CI 0.40–0.84]; P < 0.004). CONCLUSIONS—Our data suggest that impaired insulin sensitivity may be involved in the development of renal dysfunction at an early stage, before the onset of diabetes or prediabetic glucose elevations. Further studies are needed in order to establish causality. PMID:18509205

  10. Estimating correlation between multivariate longitudinal data in the presence of heterogeneity.

    PubMed

    Gao, Feng; Philip Miller, J; Xiong, Chengjie; Luo, Jingqin; Beiser, Julia A; Chen, Ling; Gordon, Mae O

    2017-08-17

    Estimating correlation coefficients among outcomes is one of the most important analytical tasks in epidemiological and clinical research. Availability of multivariate longitudinal data presents a unique opportunity to assess joint evolution of outcomes over time. Bivariate linear mixed model (BLMM) provides a versatile tool with regard to assessing correlation. However, BLMMs often assume that all individuals are drawn from a single homogenous population where the individual trajectories are distributed smoothly around population average. Using longitudinal mean deviation (MD) and visual acuity (VA) from the Ocular Hypertension Treatment Study (OHTS), we demonstrated strategies to better understand the correlation between multivariate longitudinal data in the presence of potential heterogeneity. Conditional correlation (i.e., marginal correlation given random effects) was calculated to describe how the association between longitudinal outcomes evolved over time within specific subpopulation. The impact of heterogeneity on correlation was also assessed by simulated data. There was a significant positive correlation in both random intercepts (ρ = 0.278, 95% CI: 0.121-0.420) and random slopes (ρ = 0.579, 95% CI: 0.349-0.810) between longitudinal MD and VA, and the strength of correlation constantly increased over time. However, conditional correlation and simulation studies revealed that the correlation was induced primarily by participants with rapid deteriorating MD who only accounted for a small fraction of total samples. Conditional correlation given random effects provides a robust estimate to describe the correlation between multivariate longitudinal data in the presence of unobserved heterogeneity (NCT00000125).

  11. Cross-sectional and Longitudinal Associations between Knee Joint Effusion Synovitis and Knee Pain in Older Adults.

    PubMed

    Wang, Xia; Jin, Xingzhong; Han, Weiyu; Cao, Yuelong; Halliday, Andrew; Blizzard, Leigh; Pan, Faming; Antony, Benny; Cicuttini, Flavia; Jones, Graeme; Ding, Changhai

    2016-01-01

    To describe the cross-sectional and longitudinal associations between knee regional effusion synovitis and knee pain in older adults. Data from a population-based random sample (n = 880, mean age 62 yrs, 50% women) were used. Baseline knee joint effusion synovitis was graded (0-3) using T2-weighted magnetic resonance imaging (MRI) in the suprapatellar pouch, central portion, posterior femoral recess, and subpopliteal recess. Effusion synovitis of the whole joint was defined as a score of ≥ 2 in any subregion. Other knee structural (including cartilage, bone marrow, and menisci) lesions were assessed by MRI at baseline. Knee pain was assessed by the Western Ontario and McMaster Universities Osteoarthritis Index questionnaire at baseline and 2.6 years later. Multivariable analyses were performed after adjustment for age, sex, body mass index, and other structural lesions. The prevalence of effusion synovitis was 67%. Suprapatellar pouch effusion synovitis was significantly and independently associated with increased total and nonweight-bearing knee pain in both cross-sectional and longitudinal analyses (for an increase in total knee pain of ≥ 5, RR 1.26 per grade, 95% CI 1.04-1.52), and increased weight-bearing knee pain in longitudinal analysis only. Effusion synovitis in posterior femoral recess and central portion were independently associated with increases in nonweight-bearing pain (RR 1.63 per grade, 95% CI 1.32-2.01 and RR 1.29 per grade, 95% CI 1.01-1.65, respectively) in longitudinal analyses only. Knee joint effusion synovitis has independent associations with knee pain in older adults. Suprapatellar pouch effusion synovitis is associated with nonweight-bearing and weight-bearing knee pain, while posterior femoral recess and central portion effusion synovitis are only associated with nonweight-bearing pain.

  12. The association between disease activity and NT-proBNP in 238 patients with rheumatoid arthritis: a 10-year longitudinal study

    PubMed Central

    Provan, Sella A; Angel, Kristin; Ødegård, Sigrid; Mowinckel, Petter; Atar, Dan; Kvien, Tore K

    2008-01-01

    Introduction Disease activity in patients with rheumatoid arthritis (RA) is associated with increased cardiovascular morbidity and mortality, of which N-terminal pro-brain natriuretic peptide (NT-proBNP) is a predictor. Our objective was to examine the cross-sectional and longitudinal associations between markers of inflammation, measures of RA disease activity, medication used in the treatment of RA, and NT-proBNP levels (dependent variable). Methods Two hundred thirty-eight patients with RA of less than 4 years in duration were followed longitudinally with three comprehensive assessments of clinical and radiographic data over a 10-year period. Serum samples were frozen and later batch-analyzed for NT-proBNP levels and other biomarkers. Bivariate, multivariate, and repeated analyses were performed. Results C-reactive protein (CRP) levels at baseline were cross-sectionally associated with NT-proBNP levels after adjustment for age and gender (r2 adjusted = 0.23; P < 0.05). At the 10-year follow-up, risk factors for cardiovascular disease were recorded. Duration of RA and CRP levels were independently associated with NT-proBNP in the final model that was adjusted for gender, age, and creatinine levels (r2 adjusted = 0.38; P < 0.001). In the longitudinal analyses, which adjusted for age, gender, and time of follow-up, we found that repeated measures of CRP predicted NT-proBNP levels (P < 0.001). Conclusion CRP levels are linearly associated with levels of NT-proBNP in cross-sectional and longitudinal analyses of patients with RA. The independent associations of NT-proBNP levels and markers of disease activity with clinical cardiovascular endpoints need to be further investigated. PMID:18573197

  13. An evaluation of fruit and vegetable consumption and cigarette smoking among youth.

    PubMed

    Haibach, Jeffrey P; Homish, Gregory G; Collins, R Lorraine; Ambrosone, Christine B; Giovino, Gary A

    2015-06-01

    Research across the past 4 decades has supported a cross-sectional association between adult cigarette smoking and lower fruit and vegetable consumption (FVC), and emerging research suggests higher FVC may predict cessation. Among youth, findings are limited to a few cross-sectional studies with somewhat mixed results. Here we evaluated the FVC-smoking association among youth both cross-sectionally and longitudinally. We analyzed data from a subsample of the National Longitudinal Survey of Youth 1979: Child and Young Adult. The subsample included adolescents aged 14-18 years at baseline in the year 2004. Multivariable cross-sectional analyses assessed whether baseline FVC was associated with smoking frequency among ever-smokers (n = 578). Longitudinally, the study assessed whether baseline FVC predicted smoking progression among baseline never-smokers who tried a cigarette by 4-year follow-up (n = 388). Multivariable regression models adjusted for age, gender, race/ethnicity, parental education, and health behavior orientation. Cross-sectionally, youth who consumed fruit ≥2 times per day were 53% less likely (RR = 0.47; p < .05) than those who typically did not consume fruit to be in a higher smoking frequency category. Longitudinally, the fruit consumption and smoking association was not significant (RR = 0.61; p = .282). There were no significant associations observed between vegetable consumption and smoking. Fruit consumption, but not vegetable consumption, was inversely associated with smoking frequency cross-sectionally but not longitudinally. Further research is needed to provide information on the consistency of the FVC-smoking relationship among youth and may help to elucidate possible explanatory mechanisms. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Power of Models in Longitudinal Study: Findings from a Full-Crossed Simulation Design

    ERIC Educational Resources Information Center

    Fang, Hua; Brooks, Gordon P.; Rizzo, Maria L.; Espy, Kimberly Andrews; Barcikowski, Robert S.

    2009-01-01

    Because the power properties of traditional repeated measures and hierarchical multivariate linear models have not been clearly determined in the balanced design for longitudinal studies in the literature, the authors present a power comparison study of traditional repeated measures and hierarchical multivariate linear models under 3…

  15. Modeling Associations among Multivariate Longitudinal Categorical Variables in Survey Data: A Semiparametric Bayesian Approach

    ERIC Educational Resources Information Center

    Tchumtchoua, Sylvie; Dey, Dipak K.

    2012-01-01

    This paper proposes a semiparametric Bayesian framework for the analysis of associations among multivariate longitudinal categorical variables in high-dimensional data settings. This type of data is frequent, especially in the social and behavioral sciences. A semiparametric hierarchical factor analysis model is developed in which the…

  16. Comparing the effects of entertainment media and tobacco marketing on youth smoking.

    PubMed

    Sargent, J D; Gibson, J; Heatherton, T F

    2009-02-01

    To examine the concurrent effects of exposure to movie smoking and tobacco marketing receptivity on adolescent smoking onset and progression. Cross-sectional study of 4524 northern New England adolescents aged 10-14 in 1999 with longitudinal follow-up of 2603 baseline never-smokers. Cross-sectional outcomes included ever tried smoking and higher level of lifetime smoking among 784 experimenters. The longitudinal outcome was onset of smoking among baseline never-smokers two years later. Movie smoking exposure was modelled as four population quartiles, tobacco marketing receptivity included two levels-having a favourite tobacco advert and wanting/owning tobacco promotional items. All analyses controlled for sociodemographics, other social influences, personality characteristics of the adolescent and parenting style. In the full cross-sectional sample, 17.5% had tried smoking; both exposure to movie smoking and receptivity to tobacco marketing were associated with having tried smoking. Among experimental smokers, the majority (64%) were receptive to tobacco marketing, which had a multivariate association with higher level of lifetime smoking (movie smoking did not). In the longitudinal study 9.5% of baseline never-smokers tried smoking at follow-up. Fewer never-smokers (18.5%) were receptive to tobacco marketing. Movie smoking had a multivariate association with trying smoking (receptivity to tobacco marketing did not). The results suggest separate roles for entertainment media and tobacco marketing on adolescent smoking. Both exposures deserve equal emphasis from a policy standpoint.

  17. The "Nursing Home Compare" measure of urinary/fecal incontinence: cross-sectional variation, stability over time, and the impact of case mix.

    PubMed

    Li, Yue; Schnelle, John; Spector, William D; Glance, Laurent G; Mukamel, Dana B

    2010-02-01

    To assess the impact of facility case mix on cross-sectional variations and short-term stability of the "Nursing Home Compare" incontinence quality measure (QM) and to determine whether multivariate risk adjustment can minimize such impacts. Retrospective analyses of the 2005 national minimum data set (MDS) that included approximately 600,000 long-term care residents in over 10,000 facilities in each quarterly sample. Mixed logistic regression was used to construct the risk-adjusted QM (nonshrinkage estimator). Facility-level ordinary least-squares models and adjusted R(2) were used to estimate the impact of case mix on cross-sectional and short-term longitudinal variations of currently published and risk-adjusted QMs. At least 50 percent of the cross-sectional variation and 25 percent of the short-term longitudinal variation of the published QM are explained by facility case mix. In contrast, the cross-sectional and short-term longitudinal variations of the risk-adjusted QM are much less susceptible to case-mix variations (adjusted R(2)<0.10), even for facilities with more extreme or more unstable outcome. Current "Nursing Home Compare" incontinence QM reflects considerable case-mix variations across facilities and over time, and therefore it may be biased. This issue can be largely addressed by multivariate risk adjustment using risk factors available in the MDS.

  18. The prospective relationship between sleep problems and suicidal behavior in the National Longitudinal Study of Adolescent Health.

    PubMed

    Wong, Maria M; Brower, Kirk J

    2012-07-01

    Previous research has found a longitudinal relationship between sleep problems and suicidal behavior while controlling for depression and other important covariates in a high risk sample of adolescents and controls. In this paper, we replicated this longitudinal relationship in a national sample and examined whether the relationship was partially mediated by depression, alcohol-related problems and other drug use. Study participants were 6504 adolescents from the National Longitudinal Study of Adolescent Health (ADD HEALTH). In bivariate analyses, sleep problems (i.e., having trouble falling asleep or staying asleep) at Wave 1 were associated with suicidal thoughts and suicide attempts at Waves 1, 2, and 3 (W1, 2 and 3). In multivariate analyses, controlling for depression, alcohol problems, illicit drug use, and important covariates such as gender, age, and chronic health problems, sleep problems at a previous wave predicted suicidal thoughts and suicide attempts at a subsequent wave. In mediation analyses, W2 depression significantly mediated the effect of W1 sleep problems on W3 suicide thoughts. Moreover, W2 suicidal thoughts also significantly mediated the effect of W1 sleep problems on W3 suicidal attempts. Sleep problems appear to be a robust predictor of subsequent suicidal thoughts and attempts in adolescence and young adulthood. Having trouble falling sleeping or staying asleep had both direct and indirect effects (via depression and suicidal thoughts) on suicidal behavior. Future research could determine if early intervention with sleep disturbances reduces the risk for suicidality in adolescents and young adults. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Depression and Risk of Unintentional Injury in Rural Communities—A Longitudinal Analysis of the Australian Rural Mental Health Study

    PubMed Central

    Inder, Kerry J.; Holliday, Elizabeth G.; Handley, Tonelle E.; Fragar, Lyn J.; Lower, Tony; Booth, Angela; Kelly, Brian J.

    2017-01-01

    Limited longitudinal research has examined relationships between depression and injury, particularly in rural contexts. This paper reports cross-sectional and longitudinal analyses from the Australian Rural Mental Health Study (ARMHS) exploring relationships between “probable depression” episodes and unintentional injury. Participants completed four surveys over five years. Multivariate logistic regressions were employed to assess the causal effect of prior depression episodes on subsequent injury risk. Of 2621 baseline participants, 23.3% experienced a probable depression episode recently and 15.9% reported a serious injury during the previous 12 months. Factors associated with a 12-month injury at baseline included male gender, being unemployed or unable to work, being involved in a serious incident, hazardous alcohol use, and having experienced a recent depression episode. Longitudinal analyses revealed that probable depression was significantly associated with subsequent unintentional injury (OR 1.68, 99%CI 1.20–2.35), as was male gender (OR 1.39, 99%CI 1.06–1.82), while alcohol consumption did not mediate these relationships. Campaigns to reduce the impact of mental illness should consider unintentional injuries as a contributor, while injury prevention initiatives may benefit from addressing mental health issues. Such strategies are particularly important in rural and remote areas where injuries are more common and mental health services are less readily available. PMID:28926999

  20. Multiple modality biomarker prediction of cognitive impairment in prospectively followed de novo Parkinson disease.

    PubMed

    Caspell-Garcia, Chelsea; Simuni, Tanya; Tosun-Turgut, Duygu; Wu, I-Wei; Zhang, Yu; Nalls, Mike; Singleton, Andrew; Shaw, Leslie A; Kang, Ju-Hee; Trojanowski, John Q; Siderowf, Andrew; Coffey, Christopher; Lasch, Shirley; Aarsland, Dag; Burn, David; Chahine, Lana M; Espay, Alberto J; Foster, Eric D; Hawkins, Keith A; Litvan, Irene; Richard, Irene; Weintraub, Daniel

    2017-01-01

    To assess the neurobiological substrate of initial cognitive decline in Parkinson's disease (PD) to inform patient management, clinical trial design, and development of treatments. We longitudinally assessed, up to 3 years, 423 newly diagnosed patients with idiopathic PD, untreated at baseline, from 33 international movement disorder centers. Study outcomes were four determinations of cognitive impairment or decline, and biomarker predictors were baseline dopamine transporter (DAT) single photon emission computed tomography (SPECT) scan, structural magnetic resonance imaging (MRI; volume and thickness), diffusion tensor imaging (mean diffusivity and fractional anisotropy), cerebrospinal fluid (CSF; amyloid beta [Aβ], tau and alpha synuclein), and 11 single nucleotide polymorphisms (SNPs) previously associated with PD cognition. Additionally, longitudinal structural MRI and DAT scan data were included. Univariate analyses were run initially, with false discovery rate = 0.2, to select biomarker variables for inclusion in multivariable longitudinal mixed-effect models. By year 3, cognitive impairment was diagnosed in 15-38% participants depending on the criteria applied. Biomarkers, some longitudinal, predicting cognitive impairment in multivariable models were: (1) dopamine deficiency (decreased caudate and putamen DAT availability); (2) diffuse, cortical decreased brain volume or thickness (frontal, temporal, parietal, and occipital lobe regions); (3) co-morbid Alzheimer's disease Aβ amyloid pathology (lower CSF Aβ 1-42); and (4) genes (COMT val/val and BDNF val/val genotypes). Cognitive impairment in PD increases in frequency 50-200% in the first several years of disease, and is independently predicted by biomarker changes related to nigrostriatal or cortical dopaminergic deficits, global atrophy due to possible widespread effects of neurodegenerative disease, co-morbid Alzheimer's disease plaque pathology, and genetic factors.

  1. Multivariate mixed linear model analysis of longitudinal data: an information-rich statistical technique for analyzing disease resistance data

    USDA-ARS?s Scientific Manuscript database

    The mixed linear model (MLM) is currently among the most advanced and flexible statistical modeling techniques and its use in tackling problems in plant pathology has begun surfacing in the literature. The longitudinal MLM is a multivariate extension that handles repeatedly measured data, such as r...

  2. Boosted Multivariate Trees for Longitudinal Data

    PubMed Central

    Pande, Amol; Li, Liang; Rajeswaran, Jeevanantham; Ehrlinger, John; Kogalur, Udaya B.; Blackstone, Eugene H.; Ishwaran, Hemant

    2017-01-01

    Machine learning methods provide a powerful approach for analyzing longitudinal data in which repeated measurements are observed for a subject over time. We boost multivariate trees to fit a novel flexible semi-nonparametric marginal model for longitudinal data. In this model, features are assumed to be nonparametric, while feature-time interactions are modeled semi-nonparametrically utilizing P-splines with estimated smoothing parameter. In order to avoid overfitting, we describe a relatively simple in sample cross-validation method which can be used to estimate the optimal boosting iteration and which has the surprising added benefit of stabilizing certain parameter estimates. Our new multivariate tree boosting method is shown to be highly flexible, robust to covariance misspecification and unbalanced designs, and resistant to overfitting in high dimensions. Feature selection can be used to identify important features and feature-time interactions. An application to longitudinal data of forced 1-second lung expiratory volume (FEV1) for lung transplant patients identifies an important feature-time interaction and illustrates the ease with which our method can find complex relationships in longitudinal data. PMID:29249866

  3. Gender aspects of the relationship between migraine and cardiovascular risk factors: A cross-sectional evaluation in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

    PubMed

    Goulart, Alessandra C; Santos, Itamar S; Lotufo, Paulo A; Benseñor, Isabela M

    2015-10-01

    The relationship between cardiovascular risk factors (CVRF) and migraine is controversial and might be different in both genders. These associations were evaluated in Brazilian middle-aged men and women from the Longitudinal Study of Adult Health (ELSA-Brasil). The cross-sectional relationship between our main outcome, which was migraine headache (definite, probable and overall), and CVRF was evaluated in the total sample and according to gender. We calculated frequencies and odds ratios (95% CI) for this relationship using binary and multinomial logistic regression analyses in crude, age-adjusted and multivariable models adjusted by potential confounders. Of 14,953 individuals who completed the data about headache and CVRF, the frequency of one-year migraine was of 29.5% (22.5% in women and 7.0% in men). In the multivariable-adjusted regression analyses, an inverse association between hypertension (OR, 0.53; 95% CI, 0.36-0.79), metabolic syndrome (OR, 0.65; 95% CI, 0.43-0.99) and definite migraine were confirmed for men, but not for women. In the opposite direction, a positive association between migraine headaches (definite, probable and overall) and dyslipidemia (overall migraine OR, 1.25; 95% CI, 1.13-1.38) was observed only for women, but not for men. A gender influence on the relationship between migraine and CVRF was verified in the ELSA-Brasil. © International Headache Society 2015.

  4. Angiotensin-converting Enzyme Inhibitor and Statin Medication Use and Incident Mobility Limitation in Community Older Adults. The Health, Aging and Body Composition Study

    PubMed Central

    Gray, Shelly L.; Boudreau, Robert M.; Newman, Anne B.; Studenski, Stephanie A.; Shorr, Ronald I; Bauer, Douglas C.; Simonsick, Eleanor M.; Hanlon, Joseph T

    2012-01-01

    Objective Angiotensin-converting enzyme (ACE) inhibitors and statin medications have been proposed as potential agents to prevent or delay physical disability; yet limited research has evaluated whether such use in older community dwelling adults is associated with a lower risk of incident mobility limitation. Design Longitudinal cohort study Setting Health, Aging and Body Composition (Health ABC) Participants 3055 participants who were well functioning at baseline (e.g., no mobility limitations). Measurements Summated standardized daily doses (low, medium and high) and duration of ACE inhibitor and statin use was computed. Mobility limitation (two consecutive self-reports of having any difficulty walking 1/4 mile or climbing 10 steps without resting) was assessed every 6 months after baseline. Multivariable Cox proportional hazard analyses were conducted adjusting for demographics, health status, and health behaviors. Results At baseline, ACE inhibitors and statins were used by 15.2% and 12.9%, respectively and both increased to over 25% by year 6. Over 6.5 years of follow-up, 49.8% had developed mobility limitation. In separate multivariable models, neither ACE inhibitor (multivariate hazard ratio [HR] 0.95; 95% confidence interval [CI] 0.82–1.09) nor statin use (multivariate HR 1.02; 95% CI 0.87–1.17) was associated with a lower risk for mobility limitation. Similar findings were seen in analyses examining dose- and duration-response relationships and sensitivity analyses restricted to those with hypertension. Conclusions These findings indicate that ACE inhibitors and statins widely prescribed to treat hypertension and hypercholesterolemia, respectively do not lower risk of mobility limitation, an important life quality indicator. PMID:22092102

  5. Analysis of Binary Multivariate Longitudinal Data via 2-Dimensional Orbits: An Application to the Agincourt Health and Socio-Demographic Surveillance System in South Africa

    PubMed Central

    Visaya, Maria Vivien; Sherwell, David; Sartorius, Benn; Cromieres, Fabien

    2015-01-01

    We analyse demographic longitudinal survey data of South African (SA) and Mozambican (MOZ) rural households from the Agincourt Health and Socio-Demographic Surveillance System in South Africa. In particular, we determine whether absolute poverty status (APS) is associated with selected household variables pertaining to socio-economic determination, namely household head age, household size, cumulative death, adults to minor ratio, and influx. For comparative purposes, households are classified according to household head nationality (SA or MOZ) and APS (rich or poor). The longitudinal data of each of the four subpopulations (SA rich, SA poor, MOZ rich, and MOZ poor) is a five-dimensional space defined by binary variables (questions), subjects, and time. We use the orbit method to represent binary multivariate longitudinal data (BMLD) of each household as a two-dimensional orbit and to visualise dynamics and behaviour of the population. At each time step, a point (x, y) from the orbit of a household corresponds to the observation of the household, where x is a binary sequence of responses and y is an ordering of variables. The ordering of variables is dynamically rearranged such that clusters and holes associated to least and frequently changing variables in the state space respectively, are exposed. Analysis of orbits reveals information of change at both individual- and population-level, change patterns in the data, capacity of states in the state space, and density of state transitions in the orbits. Analysis of household orbits of the four subpopulations show association between (i) households headed by older adults and rich households, (ii) large household size and poor households, and (iii) households with more minors than adults and poor households. Our results are compared to other methods of BMLD analysis. PMID:25919116

  6. Fractional Brownian motion and multivariate-t models for longitudinal biomedical data, with application to CD4 counts in HIV-positive patients.

    PubMed

    Stirrup, Oliver T; Babiker, Abdel G; Carpenter, James R; Copas, Andrew J

    2016-04-30

    Longitudinal data are widely analysed using linear mixed models, with 'random slopes' models particularly common. However, when modelling, for example, longitudinal pre-treatment CD4 cell counts in HIV-positive patients, the incorporation of non-stationary stochastic processes such as Brownian motion has been shown to lead to a more biologically plausible model and a substantial improvement in model fit. In this article, we propose two further extensions. Firstly, we propose the addition of a fractional Brownian motion component, and secondly, we generalise the model to follow a multivariate-t distribution. These extensions are biologically plausible, and each demonstrated substantially improved fit on application to example data from the Concerted Action on SeroConversion to AIDS and Death in Europe study. We also propose novel procedures for residual diagnostic plots that allow such models to be assessed. Cohorts of patients were simulated from the previously reported and newly developed models in order to evaluate differences in predictions made for the timing of treatment initiation under different clinical management strategies. A further simulation study was performed to demonstrate the substantial biases in parameter estimates of the mean slope of CD4 decline with time that can occur when random slopes models are applied in the presence of censoring because of treatment initiation, with the degree of bias found to depend strongly on the treatment initiation rule applied. Our findings indicate that researchers should consider more complex and flexible models for the analysis of longitudinal biomarker data, particularly when there are substantial missing data, and that the parameter estimates from random slopes models must be interpreted with caution. © 2015 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

  7. Multiple modality biomarker prediction of cognitive impairment in prospectively followed de novo Parkinson disease

    PubMed Central

    Caspell-Garcia, Chelsea; Simuni, Tanya; Tosun-Turgut, Duygu; Wu, I-Wei; Zhang, Yu; Nalls, Mike; Singleton, Andrew; Shaw, Leslie A.; Kang, Ju-Hee; Trojanowski, John Q.; Siderowf, Andrew; Coffey, Christopher; Lasch, Shirley; Aarsland, Dag; Burn, David; Chahine, Lana M.; Espay, Alberto J.; Foster, Eric D.; Hawkins, Keith A.; Litvan, Irene; Richard, Irene; Weintraub, Daniel

    2017-01-01

    Objectives To assess the neurobiological substrate of initial cognitive decline in Parkinson’s disease (PD) to inform patient management, clinical trial design, and development of treatments. Methods We longitudinally assessed, up to 3 years, 423 newly diagnosed patients with idiopathic PD, untreated at baseline, from 33 international movement disorder centers. Study outcomes were four determinations of cognitive impairment or decline, and biomarker predictors were baseline dopamine transporter (DAT) single photon emission computed tomography (SPECT) scan, structural magnetic resonance imaging (MRI; volume and thickness), diffusion tensor imaging (mean diffusivity and fractional anisotropy), cerebrospinal fluid (CSF; amyloid beta [Aβ], tau and alpha synuclein), and 11 single nucleotide polymorphisms (SNPs) previously associated with PD cognition. Additionally, longitudinal structural MRI and DAT scan data were included. Univariate analyses were run initially, with false discovery rate = 0.2, to select biomarker variables for inclusion in multivariable longitudinal mixed-effect models. Results By year 3, cognitive impairment was diagnosed in 15–38% participants depending on the criteria applied. Biomarkers, some longitudinal, predicting cognitive impairment in multivariable models were: (1) dopamine deficiency (decreased caudate and putamen DAT availability); (2) diffuse, cortical decreased brain volume or thickness (frontal, temporal, parietal, and occipital lobe regions); (3) co-morbid Alzheimer’s disease Aβ amyloid pathology (lower CSF Aβ 1–42); and (4) genes (COMT val/val and BDNF val/val genotypes). Conclusions Cognitive impairment in PD increases in frequency 50–200% in the first several years of disease, and is independently predicted by biomarker changes related to nigrostriatal or cortical dopaminergic deficits, global atrophy due to possible widespread effects of neurodegenerative disease, co-morbid Alzheimer’s disease plaque pathology, and genetic factors. PMID:28520803

  8. The association of longitudinal trend of fasting plasma glucose with retinal microvasculature in people without established diabetes.

    PubMed

    Hu, Yin; Niu, Yong; Wang, Dandan; Wang, Ying; Holden, Brien A; He, Mingguang

    2015-01-22

    Structural changes of retinal vasculature, such as altered retinal vascular calibers, are considered as early signs of systemic vascular damage. We examined the associations of 5-year mean level, longitudinal trend, and fluctuation in fasting plasma glucose (FPG) with retinal vascular caliber in people without established diabetes. A prospective study was conducted in a cohort of Chinese people age ≥40 years in Guangzhou, southern China. The FPG was measured at baseline in 2008 and annually until 2012. In 2012, retinal vascular caliber was assessed using standard fundus photographs and validated software. A total of 3645 baseline nondiabetic participants with baseline and follow-up data on FPG for 3 or more visits was included for statistical analysis. The associations of retinal vascular caliber with 5-year mean FPG level, longitudinal FPG trend (slope of linear regression-FPG), and fluctuation (standard deviation and root mean square error of FPG) were analyzed using multivariable linear regression analyses. Multivariate regression models adjusted for baseline FPG and other potential confounders showed that a 10% annual increase in FPG was associated independently with a 2.65-μm narrowing in retinal arterioles (P = 0.008) and a 3.47-μm widening in venules (P = 0. 0.004). Associations with mean FPG level and fluctuation were not statistically significant. Annual rising trend in FPG, but not its mean level or fluctuation, is associated with altered retinal vasculature in nondiabetic people. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

  9. Comparing the effects of entertainment media and tobacco marketing on youth smoking

    PubMed Central

    Sargent, J D; Gibson, J; Heatherton, T F

    2009-01-01

    Objectives To examine the concurrent effects of exposure to movie smoking and tobacco marketing receptivity on adolescent smoking onset and progression. Methods Cross-sectional study of 4524 northern New England adolescents aged 10–14 in 1999 with longitudinal follow-up of 2603 baseline never-smokers. Cross-sectional outcomes included ever tried smoking and higher level of lifetime smoking among 784 experimenters. The longitudinal outcome was onset of smoking among baseline never-smokers two years later. Movie smoking exposure was modelled as four population quartiles, tobacco marketing receptivity included two levels—having a favourite tobacco advert and wanting/owning tobacco promotional items. All analyses controlled for sociodemographics, other social influences, personality characteristics of the adolescent and parenting style. Results In the full cross-sectional sample, 17.5% had tried smoking; both exposure to movie smoking and receptivity to tobacco marketing were associated with having tried smoking. Among experimental smokers, the majority (64%) were receptive to tobacco marketing, which had a multivariate association with higher level of lifetime smoking (movie smoking did not). In the longitudinal study 9.5% of baseline never-smokers tried smoking at follow-up. Fewer never-smokers (18.5%) were receptive to tobacco marketing. Movie smoking had a multivariate association with trying smoking (receptivity to tobacco marketing did not). Conclusions The results suggest separate roles for entertainment media and tobacco marketing on adolescent smoking. Both exposures deserve equal emphasis from a policy standpoint. PMID:18948391

  10. Sexual Minority Disparities in Substance Use Willingness Among Youth.

    PubMed

    Gamarel, Kristi E; Mereish, Ethan H; Colby, Suzanne M; Barnett, Nancy P; Hayes, Kerri; Jackson, Kristina M

    2018-01-02

    Disparities in substance use have been observed in sexual minority youth, but less is known about willingness to use substances, an important precursor to actual use. The goal of this study was to examine willingness to use cigarettes, alcohol, and marijuana among sexual minority youth compared to their non-sexual minority counterparts using both cross-sectional and longitudinal data. The present study drew on two waves (Times 1 and 2; 6 months apart) of data collected during high school as part of a prospective study of substance use initiation and progression in Rhode Island. At Time 1, participants (N = 443) ranged in age from 15 to 20 years (M age = 16.7 years, 26.6% sexual minority, 59.5% female, 72.0% White). Participants self-reported their sexual identity and attraction, lifetime use of alcohol, cigarettes and marijuana, and cigarette, alcohol, and marijuana use willingness (i.e., if offered by a best friend or group of friends). In cross-sectional multivariate regression models, sexual minority youth were more likely to report willingness to use cigarettes (p <.05) and marijuana (p <.01) compared to their non-sexual minority counterparts. Longitudinal multivariate regression models revealed that sexual minorities were only significantly more likely to report cigarette willingness at Time 2 compared to their non-sexual minority counterparts (p <.01). There were no significant differences in alcohol use willingness in multivariable cross-sectional or longitudinal models by sexual minority status. Sexual minority youth reported more willingness than non-sexual minority youth to use substances offered by peers; however, longitudinal analyses revealed that peers appear to play a role only in willingness to smoke cigarettes for these youth, and thus peer influence may be a contributing factor in explaining tobacco-related disparities among sexual minority youth. Given that stigma and peer groups may a particular risk factor for tobacco among sexual minority youth, our findings highlight the importance of prevention programs such as social marketing approaches that correct social norms, reduce stigma, and provide refusal-skills training to reduce tobacco-related disparities among sexual minorities.

  11. Order-restricted inference for multivariate longitudinal data with applications to the natural history of hearing loss.

    PubMed

    Rosen, Sophia; Davidov, Ori

    2012-07-20

    Multivariate outcomes are often measured longitudinally. For example, in hearing loss studies, hearing thresholds for each subject are measured repeatedly over time at several frequencies. Thus, each patient is associated with a multivariate longitudinal outcome. The multivariate mixed-effects model is a useful tool for the analysis of such data. There are situations in which the parameters of the model are subject to some restrictions or constraints. For example, it is known that hearing thresholds, at every frequency, increase with age. Moreover, this age-related threshold elevation is monotone in frequency, that is, the higher the frequency, the higher, on average, is the rate of threshold elevation. This means that there is a natural ordering among the different frequencies in the rate of hearing loss. In practice, this amounts to imposing a set of constraints on the different frequencies' regression coefficients modeling the mean effect of time and age at entry to the study on hearing thresholds. The aforementioned constraints should be accounted for in the analysis. The result is a multivariate longitudinal model with restricted parameters. We propose estimation and testing procedures for such models. We show that ignoring the constraints may lead to misleading inferences regarding the direction and the magnitude of various effects. Moreover, simulations show that incorporating the constraints substantially improves the mean squared error of the estimates and the power of the tests. We used this methodology to analyze a real hearing loss study. Copyright © 2012 John Wiley & Sons, Ltd.

  12. Associations Between Traumatic Brain Injury History and Future Headache Severity in Veterans: A Longitudinal Study.

    PubMed

    Suri, Pradeep; Stolzmann, Kelly; Iverson, Katherine M; Williams, Rhonda; Meterko, Mark; Yan, Kun; Gormley, Katelyn; Pogoda, Terri K

    2017-11-01

    To determine whether traumatic brain injury (TBI) history is associated with worse headache severity outcomes. Prospective cohort study. Department of Veterans Affairs (VA) outpatient clinics. Veterans (N=2566) who completed a mail follow-up survey an average of 3 years after a comprehensive TBI evaluation (CTBIE). Not applicable. The presence or absence of TBI, and TBI severity were evaluated by a trained clinician and classified according to VA/Department of Defense clinical practice guidelines. Headache severity was evaluated at both the baseline CTBIE assessment and 3-year follow-up using a 5-level headache score ranging from 0 ("none") to 4 ("very severe") based on headache-associated activity interference in the past 30 days. We examined associations of mild and moderate/severe TBI history, as compared to no TBI history, with headache severity in cross-sectional and longitudinal analyses, with and without adjustment for potential confounders. Mean headache severity scores were 2.4 at baseline and 2.3 at 3-year follow-up. Mild TBI was associated with greater headache severity in multivariate-adjusted cross-sectional analyses (β [SE]=.61 [.07], P<.001), as compared with no TBI, but not in longitudinal analyses (β [SE]=.09 [.07], P=.20). Moderate/severe TBI was significantly associated with greater headache severity in both cross-sectional (β [SE]=.66 [.09], P<.001) and longitudinal analyses (β [SE]=.18 [.09], P=.04). Headache outcomes are poor in veterans who receive VA TBI evaluations, irrespective of past TBI exposure, but significantly worse in those with a history of moderate/severe TBI. No association was found between mild TBI and future headache severity in veterans. Veterans with headache presenting for TBI evaluations, and particularly those with moderate/severe TBI, may benefit from further evaluation and treatment of headache. Published by Elsevier Inc.

  13. Measurement bias detection with Kronecker product restricted models for multivariate longitudinal data: an illustration with health-related quality of life data from thirteen measurement occasions

    PubMed Central

    Verdam, Mathilde G. E.; Oort, Frans J.

    2014-01-01

    Highlights Application of Kronecker product to construct parsimonious structural equation models for multivariate longitudinal data. A method for the investigation of measurement bias with Kronecker product restricted models. Application of these methods to health-related quality of life data from bone metastasis patients, collected at 13 consecutive measurement occasions. The use of curves to facilitate substantive interpretation of apparent measurement bias. Assessment of change in common factor means, after accounting for apparent measurement bias. Longitudinal measurement invariance is usually investigated with a longitudinal factor model (LFM). However, with multiple measurement occasions, the number of parameters to be estimated increases with a multiple of the number of measurement occasions. To guard against too low ratios of numbers of subjects and numbers of parameters, we can use Kronecker product restrictions to model the multivariate longitudinal structure of the data. These restrictions can be imposed on all parameter matrices, including measurement invariance restrictions on factor loadings and intercepts. The resulting models are parsimonious and have attractive interpretation, but require different methods for the investigation of measurement bias. Specifically, additional parameter matrices are introduced to accommodate possible violations of measurement invariance. These additional matrices consist of measurement bias parameters that are either fixed at zero or free to be estimated. In cases of measurement bias, it is also possible to model the bias over time, e.g., with linear or non-linear curves. Measurement bias detection with Kronecker product restricted models will be illustrated with multivariate longitudinal data from 682 bone metastasis patients whose health-related quality of life (HRQL) was measured at 13 consecutive weeks. PMID:25295016

  14. Measurement bias detection with Kronecker product restricted models for multivariate longitudinal data: an illustration with health-related quality of life data from thirteen measurement occasions.

    PubMed

    Verdam, Mathilde G E; Oort, Frans J

    2014-01-01

    Application of Kronecker product to construct parsimonious structural equation models for multivariate longitudinal data.A method for the investigation of measurement bias with Kronecker product restricted models.Application of these methods to health-related quality of life data from bone metastasis patients, collected at 13 consecutive measurement occasions.The use of curves to facilitate substantive interpretation of apparent measurement bias.Assessment of change in common factor means, after accounting for apparent measurement bias.Longitudinal measurement invariance is usually investigated with a longitudinal factor model (LFM). However, with multiple measurement occasions, the number of parameters to be estimated increases with a multiple of the number of measurement occasions. To guard against too low ratios of numbers of subjects and numbers of parameters, we can use Kronecker product restrictions to model the multivariate longitudinal structure of the data. These restrictions can be imposed on all parameter matrices, including measurement invariance restrictions on factor loadings and intercepts. The resulting models are parsimonious and have attractive interpretation, but require different methods for the investigation of measurement bias. Specifically, additional parameter matrices are introduced to accommodate possible violations of measurement invariance. These additional matrices consist of measurement bias parameters that are either fixed at zero or free to be estimated. In cases of measurement bias, it is also possible to model the bias over time, e.g., with linear or non-linear curves. Measurement bias detection with Kronecker product restricted models will be illustrated with multivariate longitudinal data from 682 bone metastasis patients whose health-related quality of life (HRQL) was measured at 13 consecutive weeks.

  15. Incidence and course of adolescent deliberate self-harm in Victoria, Australia, and Washington State, USA

    PubMed Central

    Heerde, Jessica A.; Toumbourou, John W.; Hemphill, Sheryl A.; Herrenkohl, Todd I.; Patton, George C.; Catalano, Richard F.

    2015-01-01

    Purpose There have been few longitudinal studies of deliberate self-harm (DSH) in adolescents. This cross-national longitudinal study outlines risk and protective factors for DSH incidence and persistence. Methods Seventh and ninth grade students (average ages 13 and 15 years) were recruited as state-representative cohorts, surveyed and then followed-up 12-months later (N = 3,876), using the same methods in Washington State and Victoria, Australia. The retention rate was 99% in both states at follow-up. A range of risk and protective factors for DSH were examined using multivariate analyses. Results The prevalence of DSH in the past year was 1.53% in grade 7 and .91% in grade 9 for males and 4.12% and 1.34% for grade 7 and 9 females, with similar rates across states. In multivariate analyses, incident DSH was lower in Washington State (OR .67, 95% CI .45, 1.00) relative to Victoria 12-months later. Risk factors for incident DSH included being female (OR 1.93, CI 1.35, 2.76), high depressive symptoms (OR 3.52, CI 2.37, 5.21), antisocial behavior (OR 2.42, CI 1.46, 4.00), and lifetime (OR 1.85, CI 1.11, 3.08) and past month (OR 2.70, CI 1.57, 4.64) alcohol use relative to never using alcohol. Conclusions Much self-harm in adolescents resolves over the course of 12 months. Young people who self-harm have high rates of other health risk behaviors associated with family and peer risks that may all be targets for preventive intervention. PMID:26499859

  16. Multivariate longitudinal data analysis with mixed effects hidden Markov models.

    PubMed

    Raffa, Jesse D; Dubin, Joel A

    2015-09-01

    Multiple longitudinal responses are often collected as a means to capture relevant features of the true outcome of interest, which is often hidden and not directly measurable. We outline an approach which models these multivariate longitudinal responses as generated from a hidden disease process. We propose a class of models which uses a hidden Markov model with separate but correlated random effects between multiple longitudinal responses. This approach was motivated by a smoking cessation clinical trial, where a bivariate longitudinal response involving both a continuous and a binomial response was collected for each participant to monitor smoking behavior. A Bayesian method using Markov chain Monte Carlo is used. Comparison of separate univariate response models to the bivariate response models was undertaken. Our methods are demonstrated on the smoking cessation clinical trial dataset, and properties of our approach are examined through extensive simulation studies. © 2015, The International Biometric Society.

  17. A mixed-effects regression model for longitudinal multivariate ordinal data.

    PubMed

    Liu, Li C; Hedeker, Donald

    2006-03-01

    A mixed-effects item response theory model that allows for three-level multivariate ordinal outcomes and accommodates multiple random subject effects is proposed for analysis of multivariate ordinal outcomes in longitudinal studies. This model allows for the estimation of different item factor loadings (item discrimination parameters) for the multiple outcomes. The covariates in the model do not have to follow the proportional odds assumption and can be at any level. Assuming either a probit or logistic response function, maximum marginal likelihood estimation is proposed utilizing multidimensional Gauss-Hermite quadrature for integration of the random effects. An iterative Fisher scoring solution, which provides standard errors for all model parameters, is used. An analysis of a longitudinal substance use data set, where four items of substance use behavior (cigarette use, alcohol use, marijuana use, and getting drunk or high) are repeatedly measured over time, is used to illustrate application of the proposed model.

  18. Longitudinal analysis of physical activity, fluid intake, and graft function among kidney transplant recipients

    PubMed Central

    Gordon, Elisa J.; Prohaska, Thomas R.; Gallant, Mary P.; Sehgal, Ashwini R.; Strogatz, David; Yucel, Recai; Conti, David; Siminoff, Laura A.

    2010-01-01

    Summary Self-care is recommended to kidney transplant recipients as a vital component to maintain long-term graft function. However, little is known about the effects of physical activity, fluid intake, and smoking history on graft function. This longitudinal study examined the relationship between self-care practices on graft function among 88 new kidney transplant recipients in Chicago, IL and Albany, NY between 2005 and 2008. Participants were interviewed, completed surveys, and medical charts were abstracted. Physical activity, fluid intake, and smoking history at baseline were compared with changes in estimated glomerular filtration rate (eGFR) (every 6 months up to 1 year) using bivariate and multivariate regression analysis, while controlling for sociodemographic and clinical transplant variables. Multivariate analyses revealed that greater physical activity was significantly (P < 0.05) associated with improvement in GFR at 6 months; while greater physical activity, absence of smoking history, and nonwhite ethnicity were significant (P < 0.05) predictors of improvement in GFR at 12 months. These results suggest that increasing physical activity levels in kidney recipients may be an effective behavioral measure to help ensure graft functioning. Our findings suggest the need for a randomized controlled trial of exercise, fluid intake, and smoking history on GFR beyond 12 months. PMID:19619168

  19. Longitudinal analysis of physical activity, fluid intake, and graft function among kidney transplant recipients.

    PubMed

    Gordon, Elisa J; Prohaska, Thomas R; Gallant, Mary P; Sehgal, Ashwini R; Strogatz, David; Yucel, Recai; Conti, David; Siminoff, Laura A

    2009-10-01

    Self-care is recommended to kidney transplant recipients as a vital component to maintain long-term graft function. However, little is known about the effects of physical activity, fluid intake, and smoking history on graft function. This longitudinal study examined the relationship between self-care practices on graft function among 88 new kidney transplant recipients in Chicago, IL and Albany, NY between 2005 and 2008. Participants were interviewed, completed surveys, and medical charts were abstracted. Physical activity, fluid intake, and smoking history at baseline were compared with changes in estimated glomerular filtration rate (eGFR) (every 6 months up to 1 year) using bivariate and multivariate regression analysis, while controlling for sociodemographic and clinical transplant variables. Multivariate analyses revealed that greater physical activity was significantly (P < 0.05) associated with improvement in GFR at 6 months; while greater physical activity, absence of smoking history, and nonwhite ethnicity were significant (P < 0.05) predictors of improvement in GFR at 12 months. These results suggest that increasing physical activity levels in kidney recipients may be an effective behavioral measure to help ensure graft functioning. Our findings suggest the need for a randomized controlled trial of exercise, fluid intake, and smoking history on GFR beyond 12 months.

  20. Depressive symptoms and psychosocial stress at work among older employees in three continents

    PubMed Central

    2012-01-01

    Background To assess whether an association of psychosocial stress at work with depressive symptoms among older employees is evident in a set of comparable empirical studies from Europe, North America and Asia. Methods Cross-sectional and longitudinal multivariate regression analyses of data from 4 cohort studies with elder workers (2004 and 2006) testing associations of psychosocial stress at work (‘effort-reward imbalance’; ‘low control’) with depressive symptoms. Results Cross-sectional analyses from 17 countries with 14.236 participants reveal elevated odds ratios of depressive symptoms among people experiencing high work stress compared to those with low or no work stress. Adjusted odds ratios vary from 1.64 (95% CI 1.02-2.63) in Japan to 1.97 (95% CI 1.75-2.23) in Europe and 2.28 (95% CI 1.59-3.28) in the USA. Odds ratios from additional longitudinal analyses (in 13 countries) controlling for baseline depression are smaller, but remain in part significant. Conclusion Findings indicate that psychosocial stress at work might be a relevant risk factor for depressive symptoms among older employees across countries and continents. This observation may call for global policy efforts to improve quality of work in view of a rapidly aging workforce, in particular in times of economic globalization. PMID:22818354

  1. Depressive symptoms and psychosocial stress at work among older employees in three continents.

    PubMed

    Siegrist, Johannes; Lunau, Thorsten; Wahrendorf, Morten; Dragano, Nico

    2012-07-20

    To assess whether an association of psychosocial stress at work with depressive symptoms among older employees is evident in a set of comparable empirical studies from Europe, North America and Asia. Cross-sectional and longitudinal multivariate regression analyses of data from 4 cohort studies with elder workers (2004 and 2006) testing associations of psychosocial stress at work ('effort-reward imbalance'; 'low control') with depressive symptoms. Cross-sectional analyses from 17 countries with 14.236 participants reveal elevated odds ratios of depressive symptoms among people experiencing high work stress compared to those with low or no work stress. Adjusted odds ratios vary from 1.64 (95% CI 1.02-2.63) in Japan to 1.97 (95% CI 1.75-2.23) in Europe and 2.28 (95% CI 1.59-3.28) in the USA. Odds ratios from additional longitudinal analyses (in 13 countries) controlling for baseline depression are smaller, but remain in part significant. Findings indicate that psychosocial stress at work might be a relevant risk factor for depressive symptoms among older employees across countries and continents. This observation may call for global policy efforts to improve quality of work in view of a rapidly aging workforce, in particular in times of economic globalization.

  2. Multivariate Longitudinal Methods for Studying Developmental Relationships between Depression and Academic Achievement

    ERIC Educational Resources Information Center

    Grimm, Kevin J.

    2007-01-01

    Recent advances in methods and computer software for longitudinal data analysis have pushed researchers to more critically examine developmental theories. In turn, researchers have also begun to push longitudinal methods by asking more complex developmental questions. One such question involves the relationships between two developmental…

  3. The effects of incremental costs of smoking and obesity on health care costs among adults: a 7-year longitudinal study.

    PubMed

    Moriarty, James P; Branda, Megan E; Olsen, Kerry D; Shah, Nilay D; Borah, Bijan J; Wagie, Amy E; Egginton, Jason S; Naessens, James M

    2012-03-01

    To provide the simultaneous 7-year estimates of incremental costs of smoking and obesity among employees and dependents in a large health care system. We used a retrospective cohort aged 18 years or older with continuous enrollment during the study period. Longitudinal multivariate cost analyses were performed using generalized estimating equations with demographic adjustments. The annual incremental mean costs of smoking by age group ranged from $1274 to $1401. The incremental costs of morbid obesity II by age group ranged from $5467 to $5530. These incremental costs drop substantially when comorbidities are included. Obesity and smoking have large long-term impacts on health care costs of working-age adults. Controlling comorbidities impacted incremental costs of obesity but may lead to underestimation of the true incremental costs because obesity is a risk factor for developing chronic conditions.

  4. Comparing early adult outcomes of maltreated and non-maltreated children: A prospective longitudinal investigation

    PubMed Central

    Mersky, Joshua P.; Topitzes, James

    2016-01-01

    Using prospective data from the Chicago Longitudinal Study, this investigation examined associations between child maltreatment and an array of outcomes in early adulthood. Findings from bivariate and multivariate analyses indicated that verified maltreatment victims fared significantly worse than participants without an indicated maltreatment report on indicators of educational and economic attainment, criminal offending, and behavioral and mental health. Results also revealed that, while many maltreated children appeared to function well on individual outcomes, a large majority did not achieve criteria for resilience when development was assessed across domains. For example, non-maltreated participants were more than twice as likely to attain five or more positive outcomes (38.2%) on an aggregate seven-item index as the maltreated group (15.7%). These findings suggest that child maltreatment is associated with extensive and enduring impacts, reinforcing the need to develop and implement effective maltreatment prevention and intervention strategies. PMID:27667886

  5. Compulsive buying: Earlier illicit drug use, impulse buying, depression, and adult ADHD symptoms.

    PubMed

    Brook, Judith S; Zhang, Chenshu; Brook, David W; Leukefeld, Carl G

    2015-08-30

    This longitudinal study examined the association between psychosocial antecedents, including illicit drug use, and adult compulsive buying (CB) across a 29-year time period from mean age 14 to mean age 43. Participants originally came from a community-based random sample of residents in two upstate New York counties. Multivariate linear regression analysis was used to study the relationship between the participant's earlier psychosocial antecedents and adult CB in the fifth decade of life. The results of the multivariate linear regression analyses showed that gender (female), earlier adult impulse buying (IB), depressive mood, illicit drug use, and concurrent ADHD symptoms were all significantly associated with adult CB at mean age 43. It is important that clinicians treating CB in adults should consider the role of drug use, symptoms of ADHD, IB, depression, and family factors in CB. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. Compulsive Buying: Earlier Illicit Drug Use, Impulse Buying, Depression, and Adult ADHD Symptoms

    PubMed Central

    Brook, Judith S.; Zhang, Chenshu; Brook, David W.; Leukefeld, Carl G.

    2015-01-01

    This longitudinal study examined the association between psychosocial antecedents, including illicit drug use, and adult compulsive buying (CB) across a 29-year time period from mean age 14 to mean age 43. Participants originally came from a community-based random sample of residents in two upstate New York counties. Multivariate linear regression analysis was used to study the relationship between the participant’s earlier psychosocial antecedents and adult CB in the fifth decade of life. The results of the multivariate linear regression analyses showed that gender (female), earlier adult impulse buying (IB), depressive mood, illicit drug use, and concurrent ADHD symptoms were all significantly associated with adult CB at mean age 43. It is important that clinicians treating CB in adults should consider the role of drug use, symptoms of ADHD, IB, depression, and family factors in CB. PMID:26165963

  7. The Impact of Work Ability on Work Motivation and Health: A Longitudinal Study Based on Older Employees.

    PubMed

    Feißel, Annemarie; Swart, Enno; March, Stefanie

    2018-05-01

    Work participation is determined by work motivation and work ability with health as a significant component. Within the lidA-study, we explore the impact of work ability on work motivation and health with consideration of further influencing factors. Four thousand one hundred nine older employees were interviewed two times (t0 = 2011, t1 = 2014). Two multivariate analyses were performed regarding the influence of work ability on work motivation (Model 1) and health (Model 2). Within the multivariate analysis, of all the influencing factors, work ability has the strongest effect on work motivation (F = 37.761) and health (F = 76.402). It appears as a decisive determinant for both dimensions. Regarding the results, it is useful to focus on the work ability of older employees in order to maintain and boost their work motivation and health.

  8. Disproportionality and Learning Disabilities: Parsing Apart Race, Socioeconomic Status, and Language

    PubMed Central

    Shifrer, Dara; Muller, Chandra; Callahan, Rebecca

    2014-01-01

    The disproportionate identification of learning disabilities among certain socio-demographic subgroups, typically groups who are already disadvantaged, is perceived as a persistent problem within the education system. The academic and social experiences of students who are misidentified with a learning disability may be severely restricted, while students with a learning disability who are never identified are less likely to receive the accommodations and modifications necessary to learn at their maximum potential. We use the Education Longitudinal Study of 2002 to describe national patterns in learning disability identification. Results indicate that socio-demographic characteristics are predictive of identification with a learning disability. While some conventional areas of disproportionality are confirmed (males and language minorities), differences in SES entirely account for African-American and Hispanic disproportionality. Discrepancy between the results of bivariate and multivariate analyses confirms the importance of employing multivariate multilevel models in investigation of disproportionality. PMID:20587753

  9. Longitudinal study of factors affecting taste sense decline in old-old individuals.

    PubMed

    Ogawa, T; Uota, M; Ikebe, K; Arai, Y; Kamide, K; Gondo, Y; Masui, Y; Ishizaki, T; Inomata, C; Takeshita, H; Mihara, Y; Hatta, K; Maeda, Y

    2017-01-01

    The sense of taste plays a pivotal role for personal assessment of the nutritional value, safety and quality of foods. Although it is commonly recognised that taste sensitivity decreases with age, alterations in that sensitivity over time in an old-old population have not been previously reported. Furthermore, no known studies utilised comprehensive variables regarding taste changes and related factors for assessments. Here, we report novel findings from a 3-year longitudinal study model aimed to elucidate taste sensitivity decline and its related factors in old-old individuals. We utilised 621 subjects aged 79-81 years who participated in the Septuagenarians, Octogenarians, Nonagenarians Investigation with Centenarians Study for baseline assessments performed in 2011 and 2012, and then conducted follow-up assessments 3 years later in 328 of those. Assessment of general health, an oral examination and determination of taste sensitivity were performed for each. We also evaluated cognitive function using Montreal Cognitive Assessment findings, then excluded from analysis those with a score lower than 20 in order to secure the validity and reliability of the subjects' answers. Contributing variables were selected using univariate analysis, then analysed with multivariate logistic regression analysis. We found that males showed significantly greater declines in taste sensitivity for sweet and sour tastes than females. Additionally, subjects with lower cognitive scores showed a significantly greater taste decrease for salty in multivariate analysis. In conclusion, our longitudinal study revealed that gender and cognitive status are major factors affecting taste sensitivity in geriatric individuals. © 2016 John Wiley & Sons Ltd.

  10. Evaluating the Relationship between Team Performance and Joint Attention with Longitudinal Multivariate Mixed Models

    DTIC Science & Technology

    2016-09-23

    Lauren Menke3 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER H0HJ (53290813) 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS...as prior work has demonstrated that friendship can facilitate performance in decision-making and motor tasks (e.g., Shah & Jehn, 1993). However, a...Relationship between Team Performance and Joint Attention with Longitudinal Multivariate Mixed Models 5a. CONTRACT NUMBER FA8650-14-D-6501-0009 5b

  11. Aspects of posttraumatic stress disorder in long-term testicular cancer survivors: cross-sectional and longitudinal findings.

    PubMed

    Dahl, Alv A; Østby-Deglum, Marie; Oldenburg, Jan; Bremnes, Roy; Dahl, Olav; Klepp, Olbjørn; Wist, Erik; Fosså, Sophie D

    2016-10-01

    The purpose of this research is to study the prevalence of posttraumatic stress disorder (PTSD) and variables associated with PTSD in Norwegian long-term testicular cancer survivors (TCSs) both cross-sectionally and longitudinally. At a mean of 11 years after diagnosis, 1418 TCSs responded to a mailed questionnaire, and at a mean of 19 years after diagnosis, 1046 of them responded again to a modified questionnaire. Posttraumatic symptoms related to testicular cancer were self-rated with the Impact of Event Scale (IES) at the 11-year study only. An IES total score ≥35 defined Full PTSD, and a score 26-34 identified Partial PTSD, and the combination of Full and Partial PTSD defined Probable PTSD. At the 11-year study, 4.5 % had Full PTSD, 6.4 % had Partial PTSD, and 10.9 % Probable had PTSD. At both studies, socio-demographic variables, somatic health, anxiety/depression, chronic fatigue, and neurotoxic adverse effects were significantly associated with Probable PTSD in bivariate analyses. Probable anxiety disorder, poor self-rated health, and neurotoxicity remained significant with Probable PTSD in multivariate analyses at the 11-year study. In bivariate analyses, probable PTSD at that time significantly predicted socio-demographic variables, somatic health, anxiety/depression, chronic fatigue, and neurotoxicity among participants of the 19-year study, but only probable anxiety disorder remained significant in multivariable analysis. In spite of excellent prognosis, 10.9 % of long-term testicular cancer survivors had Probable PTSD at a mean of 11 years after diagnosis. Probable PTSD was significantly associated with a broad range of problems both at that time and was predictive of considerable problems at a mean of 19 year postdiagnosis. Among long-term testicular cancer survivors, 10.9 % have Probable PTSD with many associated problems, and therefore health personnel should explore stress symptoms at follow-up since efficient treatments are available.

  12. Relations Between Aortic Stiffness and Left Ventricular Mechanical Function in the Community.

    PubMed

    Bell, Vanessa; McCabe, Elizabeth L; Larson, Martin G; Rong, Jian; Merz, Allison A; Osypiuk, Ewa; Lehman, Birgitta T; Stantchev, Plamen; Aragam, Jayashri; Benjamin, Emelia J; Hamburg, Naomi M; Vasan, Ramachandran S; Mitchell, Gary F; Cheng, Susan

    2017-01-09

    Aortic stiffness impairs optimal ventricular-vascular coupling and left ventricular systolic function, particularly in the long axis. Left ventricular global longitudinal strain (GLS) has recently emerged as a sensitive measure of early cardiac dysfunction. In this study, we investigated the relation between aortic stiffness and GLS in a large community-based sample. In 2495 participants (age 39-90 years, 57% women) of the Framingham Offspring and Omni cohorts, free of cardiovascular disease, we performed tonometry to measure arterial hemodynamics and echocardiography to assess cardiac function. Aortic stiffness was evaluated as carotid-femoral pulse wave velocity and as characteristic impedance, and GLS was calculated using speckle tracking-based measurements. In multivariable analyses adjusting for age, sex, height, systolic blood pressure, augmentation index, left ventricular structure, and additional cardiovascular risk factors, increased carotid-femoral pulse wave velocity (B±SE: 0.122±0.030% strain per SD, P<0.0001) and characteristic impedance (0.090±0.029, P=0.002) were both associated with worse GLS. We observed effect modification by sex on the relation between characteristic impedance and GLS (P=0.004); in sex-stratified multivariable analyses, the relation between greater characteristic impedance and worse GLS persisted in women (0.145±0.039, P=0.0003) but not in men (P=0.73). Multiple measures of increased aortic stiffness were cross-sectionally associated with worse GLS after adjusting for hemodynamic variables. Parallel reductions in left ventricular long axis shortening and proximal aortic longitudinal strain in individuals with a stiffened proximal aorta, from direct mechanical ventricular-vascular coupling, offers an alternative explanation for the observed relations. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  13. Contribution of speech and language difficulties to health-related quality-of-life in Australian children: A longitudinal analysis.

    PubMed

    Feeney, Rachel; Desha, Laura; Khan, Asaduzzaman; Ziviani, Jenny

    2017-04-01

    The trajectory of health-related quality-of-life (HRQoL) for children aged 4-9 years and its relationship with speech and language difficulties (SaLD) was examined using data from the Longitudinal Study of Australian Children (LSAC). Generalized linear latent and mixed modelling was used to analyse data from three waves of the LSAC across four HRQoL domains (physical, emotional, social and school functioning). Four domains of HRQoL, measured using the Paediatric Quality-of-Life Inventory (PedsQL™), were examined to find the contribution of SaLD while accounting for child-specific factors (e.g. gender, ethnicity, temperament) and family characteristics (social ecological considerations and psychosocial stressors). In multivariable analyses, one measure of SaLD, namely parent concern about receptive language, was negatively associated with all HRQoL domains. Covariates positively associated with all HRQoL domains included child's general health, maternal mental health, parental warmth and primary caregiver's engagement in the labour force. Findings suggest that SaLD are associated with reduced HRQoL. For most LSAC study children, having typical speech/language skills was a protective factor positively associated with HRQoL.

  14. Realizing Women Living with HIV's Reproductive Rights in the Era of ART: The Negative Impact of Non-consensual HIV Disclosure on Pregnancy Decisions Amongst Women Living with HIV in a Canadian Setting.

    PubMed

    Duff, Putu; Kestler, Mary; Chamboko, Patience; Braschel, Melissa; Ogilvie, Gina; Krüsi, Andrea; Montaner, Julio; Money, Deborah; Shannon, Kate

    2018-04-07

    To better understand the structural drivers of women living with HIV's (WLWH's) reproductive rights and choices, this study examined the structural correlates, including non-consensual HIV disclosure, on WLWH's pregnancy decisions and describes access to preconception care. Analyses drew on data (2014-present) from SHAWNA, a longitudinal community-based cohort with WLWH across Metro-Vancouver, Canada. Multivariable logistic regression was used to model the effect of non-consensual HIV disclosure on WLWH's pregnancy decisions. Of the 218 WLWH included in our analysis, 24.8% had ever felt discouraged from becoming pregnant and 11.5% reported accessing preconception counseling. In multivariable analyses, non-consensual HIV disclosure was positively associated with feeling discouraged from wanting to become pregnant (AOR 3.76; 95% CI 1.82-7.80). Non-consensual HIV disclosure adversely affects WLWH's pregnancy decisions. Supporting the reproductive rights of WLWH will require further training among general practitioners on the reproductive health of WLWH and improved access to women-centred, trauma-informed care, including non-judgmental preconception counseling.

  15. Longitudinal Relationships Between Productive Activities and Functional Health in Later Years: A Multivariate Latent Growth Curve Modeling Approach.

    PubMed

    Choi, Eunhee; Tang, Fengyan; Kim, Sung-Geun; Turk, Phillip

    2016-10-01

    This study examined the longitudinal relationships between functional health in later years and three types of productive activities: volunteering, full-time, and part-time work. Using the data from five waves (2000-2008) of the Health and Retirement Study, we applied multivariate latent growth curve modeling to examine the longitudinal relationships among individuals 50 or over. Functional health was measured by limitations in activities of daily living. Individuals who volunteered, worked either full time or part time exhibited a slower decline in functional health than nonparticipants. Significant associations were also found between initial functional health and longitudinal changes in productive activity participation. This study provides additional support for the benefits of productive activities later in life; engagement in volunteering and employment are indeed associated with better functional health in middle and old age. © The Author(s) 2016.

  16. Longitudinal assessment of treatment effects on pulmonary ventilation using 1H/3He MRI multivariate templates

    NASA Astrophysics Data System (ADS)

    Tustison, Nicholas J.; Contrella, Benjamin; Altes, Talissa A.; Avants, Brian B.; de Lange, Eduard E.; Mugler, John P.

    2013-03-01

    The utitlity of pulmonary functional imaging techniques, such as hyperpolarized 3He MRI, has encouraged their inclusion in research studies for longitudinal assessment of disease progression and the study of treatment effects. We present methodology for performing voxelwise statistical analysis of ventilation maps derived from hyper­ polarized 3He MRI which incorporates multivariate template construction using simultaneous acquisition of IH and 3He images. Additional processing steps include intensity normalization, bias correction, 4-D longitudinal segmentation, and generation of expected ventilation maps prior to voxelwise regression analysis. Analysis is demonstrated on a cohort of eight individuals with diagnosed cystic fibrosis (CF) undergoing treatment imaged five times every two weeks with a prescribed treatment schedule.

  17. A joint modeling and estimation method for multivariate longitudinal data with mixed types of responses to analyze physical activity data generated by accelerometers.

    PubMed

    Li, Haocheng; Zhang, Yukun; Carroll, Raymond J; Keadle, Sarah Kozey; Sampson, Joshua N; Matthews, Charles E

    2017-11-10

    A mixed effect model is proposed to jointly analyze multivariate longitudinal data with continuous, proportion, count, and binary responses. The association of the variables is modeled through the correlation of random effects. We use a quasi-likelihood type approximation for nonlinear variables and transform the proposed model into a multivariate linear mixed model framework for estimation and inference. Via an extension to the EM approach, an efficient algorithm is developed to fit the model. The method is applied to physical activity data, which uses a wearable accelerometer device to measure daily movement and energy expenditure information. Our approach is also evaluated by a simulation study. Copyright © 2017 John Wiley & Sons, Ltd.

  18. The effect of spousal violence on women's health: findings from the Stree Arogya Shodh in Goa, India.

    PubMed

    Chowdhary, N; Patel, V

    2008-01-01

    Spousal violence has wide-ranging effects on the physical, reproductive, sexual and psychological health of women. There are few longitudinal studies that describe this association in developing countries. To test the hypothesis that spousal violence is an independent risk factor for a broad range of adverse health outcomes in women. A population-based cohort study of women living in the catchment area of a primary health center in north Goa. Two thousand four hundred and ninety-four of 3000 randomly selected women were recruited of whom 1750 married women were included for this paper. Each participant was assessed at baseline with a structured interview for the assessment of exposure to spousal violence (verbal, physical, sexual) over two time periods (lifetime; recent in the past three months). The interview collected data on gynecological complaints and the Revised Clinical Interview Schedule was used for the diagnosis of depressive disorder. Laboratory tests for anemia and sexually transmitted infections (STI) were carried out. Longitudinal data was collected after six and 12 months on these outcomes. In addition, baseline measures for nutritional status and menstrual health were also obtained. Univariate analyses were carried out on the cross-sectional and longitudinal data to assess the association between each type of spousal violence and each health outcome. Multivariate analyses adjusted for age, literacy, household per capita income. Logistic regression was used for all analyses in Stata (Version 10). Lifetime spousal violence was reported by 290 (16.6%, 95%CI=14.9-18.4) women; recent violence was reported by 230 (13.0%, 95%CI=11.6-14.8). The cross-sectional data showed an association between violence and a range of self-reported gynecological complaints, low Body Mass Index, depressive disorder and attempted suicide. The longitudinal analyses confirmed these associations only for STI and attempted suicide. Spousal violence is specifically associated as an independent risk factor for two adverse women's health outcomes, viz., STI and attempted suicide. Public health and clinical programs targeting these outcomes must specifically address spousal violence.

  19. Longitudinal measurements of oxygen consumption in growing infants during the first weeks after birth: old data revisited.

    PubMed

    Sinclair, J C; Thorlund, K; Walter, S D

    2013-01-01

    In a study conducted in 1966-1969, longitudinal measurements were made of the metabolic rate in growing infants. Statistical methods for analyzing longitudinal data weren't readily accessible at that time. To measure minimal rates of oxygen consumption (V·O2, ml/min) in growing infants during the first postnatal weeks and to determine the relationships between postnatal increases in V·O2, body size and postnatal age. We studied 61 infants of any birth weight or gestational age, including 19 of very low birth weight. The infants, nursed in incubators, were clinically well and without need of oxygen supplementation or respiratory assistance. Serial measures of V·O2 using a closed-circuit method were obtained at approximately weekly intervals. V·O2 was measured under thermoneutral conditions with the infant asleep or resting quietly. Data were analyzed using mixed-effects models. During early postnatal growth, V·O2 rises as surface area (m(2))(1.94) (standard error, SE 0.054) or body weight (kg)(1.24) (SE 0.033). Multivariate analyses show statistically significant effects of both size and age. Reference intervals (RIs) for V·O2 for fixed values of body weight and postnatal age are presented. As V·O2 rises with increasing size and age, there is an increase in the skin-operative environmental temperature gradient (T skin-op) required for heat loss. Required T skin-op can be predicted from surface area and heat loss (heat production minus heat storage). Generation of RIs for minimal rates of V·O2 in growing infants from the 1960s was enabled by application of mixed-effects statistical models for analyses of longitudinal data. Results apply to the precaffeine era of neonatal care. Copyright © 2013 S. Karger AG, Basel.

  20. Investigation into longitudinal dietary behaviours and household socio-economic indicators and their association with BMI Z-score and fat mass in South African adolescents: the Birth to Twenty (Bt20) cohort.

    PubMed

    Feeley, Alison B; Musenge, Eustasius; Pettifor, John M; Norris, Shane A

    2013-04-01

    The present study aimed to assess the relationship between dietary habits, change in socio-economic status and BMI Z-score and fat mass in a cohort of South African adolescents. In the longitudinal study, data were collected at ages 13, 15 and 17 years on a birth cohort who have been followed since 1990. Black participants with complete dietary habits data (breakfast consumption during the week and at weekends, snacking while watching television, eating main meal with family, lunchbox use, number of tuck shop purchases, fast-food consumption, confectionery consumption and sweetened beverage consumption) at all three ages and body composition data at age 17 years were included in the analyses. Generalized estimating equations were used to test the associations between individual longitudinal dietary habits and obesity (denoted by BMI Z-score and fat mass) with adjustments for change in socio-economic status between birth and age 12 years. Birth to Twenty (Bt20) study, Soweto-Johannesburg, South Africa. Adolescents (n 1298; 49·7 % male). In males, the multivariable analyses showed that soft drink consumption was positively associated with both BMI Z-score and fat mass (P < 0·05). Furthermore, these relationships remained the same after adjustment for socio-economic indicators (P < 0·05). No associations were found in females. Longitudinal soft drink consumption was associated with increased BMI Z-score and fat mass in males only. Fridge ownership at birth (a proxy for greater household disposable income in this cohort) was shown to be associated with both BMI Z-score and fat mass.

  1. Angiotensin-converting enzyme inhibitor and statin use and incident mobility limitation in community-dwelling older adults: the Health, Aging and Body Composition study.

    PubMed

    Gray, Shelly L; Boudreau, Robert M; Newman, Anne B; Studenski, Stephanie A; Shorr, Ronald I; Bauer, Douglas C; Simonsick, Eleanor M; Hanlon, Joseph T

    2011-12-01

    To evaluate whether the use of angiotensin-converting enzyme (ACE) inhibitors and statins is associated with a lower risk of incident mobility limitation in older community dwelling adults. Longitudinal cohort study. Health, Aging and Body Composition (Health ABC) study. Three thousand fifty-five participants who were well functioning at baseline (no mobility limitations). Summated standardized daily doses (low, medium, high) and duration of ACE inhibitor and statin use were computed. Mobility limitation (two consecutive self-reports of having any difficulty walking one-quarter of a mile or climbing 10 steps without resting) was assessed every 6 months after baseline. Multivariable Cox proportional hazards analyses were conducted, adjusting for demographics, health status, and health behaviors. At baseline, 15.2% used ACE inhibitors and 12.9% used statins; use of both was greater than 25% by Year 6. Over 6.5 years of follow-up, 49.8% had developed mobility limitation. In separate multivariable models, neither ACE inhibitor (multivariate hazard ratio (HR) = 0.95, 95% confidence interval (CI) = 0.82-1.09) nor statin use (multivariate HR = 1.02, 95% CI = 0.87-1.17) was associated with lower risk of mobility limitation. Similar findings were seen in analyses examining dose-response and duration-response relationships and a sensitivity analysis restricted to those with hypertension. ACE inhibitors and statins widely prescribed to treat hypertension and hypercholesterolemia, respectively, do not lower risk of mobility limitation, an important indicator of quality of life. © 2011, Copyright the Authors Journal compilation © 2011, The American Geriatrics Society.

  2. Assessment of Platelet Function in Traumatic Brain Injury-A Retrospective Observational Study in the Neuro-Critical Care Setting.

    PubMed

    Lindblad, Caroline; Thelin, Eric Peter; Nekludov, Michael; Frostell, Arvid; Nelson, David W; Svensson, Mikael; Bellander, Bo-Michael

    2018-01-01

    Despite seemingly functional coagulation, hemorrhagic lesion progression is a common and devastating condition following traumatic brain injury (TBI), stressing the need for new diagnostic techniques. Multiple electrode aggregometry (MEA) measures platelet function and could aid in coagulopathy assessment following TBI. The aims of this study were to evaluate MEA temporal dynamics, influence of concomitant therapy, and its capabilities to predict lesion progression and clinical outcome in a TBI cohort. Adult TBI patients in a neurointensive care unit that underwent MEA sampling were retrospectively included. MEA was sampled if the patient was treated with antiplatelet therapy, bled heavily during surgery, or had abnormal baseline coagulation values. We assessed platelet activation pathways involving the arachidonic acid receptor (ASPI), P2Y 12 receptor, and thrombin receptor (TRAP). ASPI was the primary focus of analysis. If several samples were obtained, they were included. Retrospective data were extracted from hospital charts. Outcome variables were radiologic hemorrhagic progression and Glasgow Outcome Scale assessed prospectively at 12 months posttrauma. MEA levels were compared between patients on antiplatelet therapy. Linear mixed effect models and uni-/multivariable regression models were used to study longitudinal dynamics, hemorrhagic progression and outcome, respectively. In total, 178 patients were included (48% unfavorable outcome). ASPI levels increased from initially low values in a time-dependent fashion ( p  < 0.001). Patients on cyclooxygenase inhibitors demonstrated low ASPI levels ( p  < 0.001), while platelet transfusion increased them ( p  < 0.001). The first ASPI ( p  = 0.039) and TRAP ( p  = 0.009) were significant predictors of outcome, but not lesion progression, in univariate analyses. In multivariable analysis, MEA values were not independently correlated with outcome. A general longitudinal trend of MEA is identified in this TBI cohort, even in patients without known antiplatelet therapies. Values appear also affected by platelet inhibitory treatment and by platelet transfusions. While significant in univariate models to predict outcome, MEA values did not independently correlate to outcome or lesion progression in multivariable analyses. Further prospective studies to monitor coagulation in TBI patients are warranted, in particular the interpretation of pathological MEA values in patients without antiplatelet therapies.

  3. Short sleep duration as a risk factor for hypercholesterolemia: analyses of the National Longitudinal Study of Adolescent Health.

    PubMed

    Gangwisch, James E; Malaspina, Dolores; Babiss, Lindsay A; Opler, Mark G; Posner, Kelly; Shen, Sa; Turner, J Blake; Zammit, Gary K; Ginsberg, Henry N

    2010-07-01

    To explore the relationship between sleep duration in adolescence and hypercholesterolemia in young adulthood. Experimental sleep restriction has been shown to significantly increase total cholesterol and LDL cholesterol levels in women. Short sleep duration has been found in cross sectional studies to be associated with higher total cholesterol and lower HDL cholesterol levels. Sleep deprivation could increase the risk for hypercholesterolemia by increasing appetite and dietary consumption of saturated fats, decreasing motivation to engage in regular physical activity, and increasing stress and resultant catecholamine induced lipolysis. No previous published population studies have examined the longitudinal relationship between sleep duration and high cholesterol. Multivariate longitudinal analyses stratified by sex of the ADD Health using logistic regression. United States nationally representative, school-based, probability-based sample. Adolescents (n = 14,257) in grades 7 to 12 at baseline (1994-95) and ages 18 to 26 at follow-up (2001-02). Among females, each additional hour of sleep was associated with a significantly decreased odds of being diagnosed with high cholesterol in young adulthood (OR = 0.85, 95% CI 0.75-0.96) after controlling for covariates. Additional sleep was associated with decreased, yet not statistically significant, odds ratios for hypercholesterolemia in males (OR = 0.91, 95% CI 0.79-1.05). Short sleep durations in adolescent women could be a significant risk factor for high cholesterol. Interventions that lengthen sleep could potentially serve as treatments and as primary preventative measures for hypercholesterolemia.

  4. Academic performance, educational aspiration and birth outcomes among adolescent mothers: a national longitudinal study

    PubMed Central

    2014-01-01

    Background Maternal educational attainment has been associated with birth outcomes among adult mothers. However, limited research explores whether academic performance and educational aspiration influence birth outcomes among adolescent mothers. Methods Data from Waves I and IV of the National Longitudinal Study of Adolescent Health (Add Health) were used. Adolescent girls whose first pregnancy occurred after Wave I, during their adolescence, and ended with a singleton live birth were included. Adolescents’ grade point average (GPA), experience of ever skipping a grade and ever repeating a grade, and their aspiration to attend college were examined as predictors of birth outcomes (birthweight and gestational age; n = 763). Univariate statistics, bivariate analyses and multivariable models were run stratified on race using survey procedures. Results Among Black adolescents, those who ever skipped a grade had higher offspring’s birthweight. Among non-Black adolescents, ever skipping a grade and higher educational aspiration were associated with higher offspring’s birthweight; ever skipping a grade was also associated with higher gestational age. GPA was not statistically significantly associated with either birth outcome. The addition of smoking during pregnancy and prenatal care visit into the multivariable models did not change these associations. Conclusions Some indicators of higher academic performance and aspiration are associated with better birth outcomes among adolescents. Investing in improving educational opportunities may improve birth outcomes among teenage mothers. PMID:24422664

  5. Two-part models with stochastic processes for modelling longitudinal semicontinuous data: Computationally efficient inference and modelling the overall marginal mean.

    PubMed

    Yiu, Sean; Tom, Brian Dm

    2017-01-01

    Several researchers have described two-part models with patient-specific stochastic processes for analysing longitudinal semicontinuous data. In theory, such models can offer greater flexibility than the standard two-part model with patient-specific random effects. However, in practice, the high dimensional integrations involved in the marginal likelihood (i.e. integrated over the stochastic processes) significantly complicates model fitting. Thus, non-standard computationally intensive procedures based on simulating the marginal likelihood have so far only been proposed. In this paper, we describe an efficient method of implementation by demonstrating how the high dimensional integrations involved in the marginal likelihood can be computed efficiently. Specifically, by using a property of the multivariate normal distribution and the standard marginal cumulative distribution function identity, we transform the marginal likelihood so that the high dimensional integrations are contained in the cumulative distribution function of a multivariate normal distribution, which can then be efficiently evaluated. Hence, maximum likelihood estimation can be used to obtain parameter estimates and asymptotic standard errors (from the observed information matrix) of model parameters. We describe our proposed efficient implementation procedure for the standard two-part model parameterisation and when it is of interest to directly model the overall marginal mean. The methodology is applied on a psoriatic arthritis data set concerning functional disability.

  6. Pulmonary Function and Survival in Idiopathic vs Secondary Usual Interstitial Pneumonia

    PubMed Central

    Strand, Matthew J.; Sprunger, David; Cosgrove, Gregory P.; Fernandez-Perez, Evans R.; Frankel, Stephen K.; Huie, Tristan J.; Olson, Amy L.; Solomon, Joshua; Brown, Kevin K.

    2014-01-01

    BACKGROUND: The usual interstitial pneumonia (UIP) pattern of lung injury may occur in the setting of connective tissue disease (CTD), but it is most commonly found in the absence of a known cause, in the clinical context of idiopathic pulmonary fibrosis (IPF). Our objective was to observe and compare longitudinal changes in pulmonary function and survival between patients with biopsy-proven UIP found in the clinical context of either CTD or IPF. METHODS: We used longitudinal data analytic models to compare groups (IPF [n = 321] and CTD-UIP [n = 56]) on % predicted FVC (FVC %) or % predicted diffusing capacity of the lung for carbon monoxide (Dlco %), and we used both unadjusted and multivariable techniques to compare survival between these groups. RESULTS: There were no significant differences between groups in longitudinal changes in FVC % or Dlco % up to diagnosis, or from diagnosis to 10 years beyond (over which time, the mean decrease in FVC % per year [95% CI] was 4.1 [3.4, 4.9] for IPF and 3.5 [1.8, 5.1] for CTD-UIP, P = .49 for difference; and the mean decrease in Dlco % per year was 4.7 [4.0, 5.3] for IPF and 4.3 [3.0, 5.6] for CTD-UIP, P = .60 for difference). Despite the lack of differences in pulmonary function, subjects with IPF had worse survival in unadjusted (log-rank P = .003) and certain multivariable analyses. CONCLUSIONS: Despite no significant differences in changes in pulmonary function over time, patients with CTD-UIP (at least those with certain classifiable CTDs) live longer than patients with IPF—an observation that we suspect is due to an increased rate of mortal acute exacerbations in patients with IPF. PMID:24700149

  7. The effects of age, education, and treatment on physical, sexual and body concern symptoms among multimorbid, colorectal cancer survivors.

    PubMed

    Naik, Aanand D; Uy, Natalie; Anaya, Daniel A; Moye, Jennifer

    2015-07-01

    Less is known about longitudinal changes in quality of life between treatment completion and early survivorship among multimorbid cancer survivors. The current study describes longitudinal changes in quality of life among a multimorbid cohort of US Veterans diagnosed and treated for colorectal cancer. A sample of 68 multimorbid adults with colon and/or rectal cancer who received one or more treatment options (surgery, chemo or radiation therapy) was recruited. Participants were not excluded by cancer stage unless they reported being in hospice or similar status. Comprehensive assessments of quality of life and treatment side-effects were conducted 6, 12, and 18months after diagnosis. Descriptive statistics characterized treatment side-effects and changes in quality-of-life domains longitudinally. Multivariate Analysis of Variance identified sociodemographic and clinical variables associated with quality of life changes. Many physical symptoms improved from 6 to 18months following diagnosis, while some remained stable. Sexual symptoms worsened, attributable to increasing rates of dysfunction in older patients. Low education attainment was predictive of worse physical symptoms (F=5.59, p=.023) and associated with body concerns (F=5.7; p=.005) over time. Advanced cancer stage (F=4.94; p<.04) and receipt of chemotherapy (F=4.21; p<.05) independently predicted body concerns in multivariate analyses. Endorsement of physical and sexual symptoms and body concerns occurs in different patterns over time among multimorbid colorectal cancer survivors. Low education attainment is consistently associated with physical symptoms and body concerns. Cancer stage and chemotherapy are predictive of body concerns, but not physical or sexual symptoms. Published by Elsevier Ltd.

  8. Impact of tobacco advertisements on tobacco use among urban adolescents in India: results from a longitudinal study.

    PubMed

    Arora, Monika; Gupta, Vinay K; Nazar, Gaurang P; Stigler, Melissa H; Perry, Cheryl L; Reddy, K Srinath

    2012-05-01

    To examine the longitudinal relationship between exposure and receptivity to tobacco advertisements and progression towards tobacco use among adolescents in India. A 2-year longitudinal group-randomised trial, Mobilizing Youth for Tobacco Related Initiatives (MYTRI), was undertaken from 2004 to 2006 in 32 schools in Delhi and Chennai. Among the control schools (n=16), mixed-effects regression models were used to assess the objectives. Subjects Students who were non-susceptible, never users of tobacco (n=2782) at baseline (2004) in the control schools of Project MYTRI, who progressed academically and were followed up at endline (2006). Progression towards tobacco use (on tobacco uptake continuum). Bivariate results suggest that exposure to tobacco advertisements at baseline was associated in a dose-dependent manner with progression at endline. Students exposed at more than four places were 1.5 times (95% CI 1.12 to 1.94; p<0.05) more likely to progress towards tobacco use at endline versus those not exposed. Among boys, those exposed at more than four places were 1.7 times more likely to progress (95% CI 1.14 to 2.62; p<0.05). These significant results disappeared in multivariate analysis, when other psychosocial risk factors for tobacco use were controlled. In both bivariate and multivariate analyses, the risk of progression at endline was more than two times higher (95% CI 1.28 to 4.32; p<0.05) among boys who were highly receptive versus non-receptive boys. The same relationship did not hold among girls. High receptivity to tobacco advertising predicts future progression to tobacco use among boys in India. Suggestive evidence exists of a causal relationship between tobacco marketing and adolescent tobacco use.

  9. Severe menopausal symptoms associated with reduced adherence to antiretroviral therapy among perimenopausal and menopausal women living with HIV in Metro Vancouver.

    PubMed

    Duff, Putu K; Money, Deborah M; Ogilvie, Gina S; Ranville, Florence; Kestler, Mary; Braschel, Melissa C; Pick, Neora; Shannon, Kate

    2018-05-01

    Although more women living with HIV (WLWH) are entering midlife, the experiences of perimenopausal and menopausal WLWH, including the effects of menopausal symptoms severity, remain understudied. This study longitudinally investigated the correlates of antiretroviral therapy (ART) adherence among perimenopausal and menopausal WLWH from Metro Vancouver. Analyses drew on longitudinal data (2014-2017) from Sexual health and HIV/AIDS: Women's Longitudinal Needs Assessment, an ongoing community-based cohort of WLWH, aged 14+, from Metro Vancouver, Canada. At baseline and biannually, participants completed an interviewer-administered questionnaire. Bivariate and multivariable logistic regression with generalized estimating equations were used to identify the correlates of self-reported <95% ART adherence. The sample included 109 perimenopausal and menopausal WLWH (233 observations), with a median age of 49 years (IQR 44-53). Whereas most (68.8%) participants experienced menopausal symptoms, only 17% had received treatment (eg, antidepressants, hormone therapy) at baseline. In multivariable analysis, severe menopausal symptoms (adjusted odds ratio [AOR] 1.03, 95% confidence interval [CI] 1.00-1.06), injection drug use (AOR 2.86, 95% CI 1.44-5.55), and physical/sexual violence (AOR 2.33, 95% CI 1.02-5.26) independently and positively correlated with <95% adherence. These findings suggest that menopausal symptoms may undermine ART adherence, with overlapping vulnerabilities such as injection drug use and sexual/physical violence further exacerbating poor ART adherence. Women-centred, trauma-informed care approaches to detect menopause and treat menopausal symptoms are urgently needed. Such approaches should holistically address the intersecting barriers to adherence and link WLWH to peripheral health and social services, including trauma counseling and evidence-based harm reduction services.

  10. Work-family conflict and health in Swedish working women and men: a 2-year prospective analysis (the SLOSH study).

    PubMed

    Leineweber, Constanze; Baltzer, Maria; Magnusson Hanson, Linda L; Westerlund, Hugo

    2013-08-01

    Research has suggested that gender is related to perceptions of work-family conflict (WFC) and an underlying assumption is that interference of paid work with family life will burden women more than men. There is, however, mixed evidence as to whether men and women report different levels of WFC. Even less studies investigate gender differences in health outcomes of WFC. Also the number of longitudinal studies in this field is low. Based on the Swedish Longitudinal Occupational Survey of Health, we prospectively examined the effects of WFC on three different health measures representing a wide spectrum off ill health (i.e. self-rated health, emotional exhaustion and problem drinking). Logistic regression analyses were used to analyse multivariate associations between WFC in 2008 and health 2 years later. The results show that WFC was associated with an increased risk of emotional exhaustion among both men and women. Gender differences are suggested as WFC was related to an increased risk for poor self-rated health among women and problem drinking among men. Interaction analyses revealed that the risk of poor self-rated health was substantially more influenced by WFC among women than among men. We conclude that, despite the fact that women experience conflict between work and family life slightly more often than men, both men's and women's health is negatively affected by this phenomenon.

  11. Obesity and Functioning Among Individuals with Chronic Obstructive Pulmonary Disease (COPD).

    PubMed

    Katz, Patricia; Iribarren, Carlos; Sanchez, Gabriela; Blanc, Paul D

    2016-06-01

    In COPD, body composition studies have focused primarily on low BMI. We examined obesity (BMI ≥ 30 kg/m(2)) as a risk factor for poor function and longitudinal functional decline. Data from a longitudinal cohort of adults with COPD (n = 1096) and an age- and sex-matched comparison group collected in two in-person visits ∼49 months apart were analyzed. Two measures of functioning were examined: six-minute walk distance (6MWD) and Short Physical Performance Battery (SPPB). Multivariate regression analyses examined relationships of obesity with functioning. Secondary analyses stratified by GOLD classification (GOLD-0/1, GOLD-2, GOLD-3/4). Obesity (53% of COPD cohort) was associated cross-sectionally with 6MWD and SPPB in COPD, and only with 6MWD in the comparison group. Obesity predicted significant functional decline in 6MWD for individuals with COPD (odds ratio (OR) for decline [95% CI] 1.8 [1.1, 2.9]), but not the comparison group. Secondary analyses revealed that the risk of decline was significant only in those with more severe COPD (GOLD 3/4, OR = 2.3 [1.0, 5.4]). Obesity was highly prevalent and was associated with poor function concurrently and with subsequent decline in 6MWD in COPD. Obesity in COPD should be considered a risk not only for more co-morbidities and greater health care use, but also for functional decline.

  12. Energy intake and leukocyte telomere length in young adults123

    PubMed Central

    Goldberger, Nehama; Kimura, Masayuki; Sinnreich, Ronit; Aviv, Abraham

    2012-01-01

    Background: Dietary energy restriction in mammals, particularly at a young age, extends the life span. Leukocyte telomere length (LTL) is thought to be a bioindicator of aging in humans. High n−6 (omega-6) PUFA intake may accelerate LTL attrition. Objective: We determined whether lower energy and higher PUFA intakes in young adulthood are associated with shorter LTL in cross-sectional and longitudinal analyses. Design: In a longitudinal observational study (405 men, 204 women), diet was determined at baseline by a semiquantitative food-frequency questionnaire, and LTL was determined by Southern blots at mean ages of 30.1 y (baseline) and 43.2 y (follow-up). Spearman correlations and multivariable linear regression were used. Results: Baseline energy intake was inversely associated with follow-up LTL in men (standardized β = −0.171, P = 0.0005) but not in women (P = 0.039 for sex interaction). The difference in men between the highest and lowest quintiles of energy was 244 base pairs (bp) (95% CI: 59, 429 bp) and between extreme quintiles of LTL was 440 kcal (95% CI: 180, 700 kcal). Multivariable adjustment modestly attenuated the association (β = −0.157, P = 0.002). Inverse associations, which were noted for all macronutrients, were strongest for the unsaturated fatty acids. In multivariable models including energy and the macronutrients (as percentage of energy), the significant inverse energy-LTL association (but not the PUFA-LTL association) persisted. The energy-LTL association was restricted to never smokers (standardized β = −0.259, P = 0.0008; P = 0.050 for the smoking × calorie interaction). Conclusions: The inverse calorie intake–LTL association is consistent with trial data showing beneficial effects of calorie restriction on aging biomarkers. Further exploration of energy intake and LTL dynamics in the young is needed. PMID:22237065

  13. Evaluating Measurement of Dynamic Constructs: Defining a Measurement Model of Derivatives

    PubMed Central

    Estabrook, Ryne

    2015-01-01

    While measurement evaluation has been embraced as an important step in psychological research, evaluating measurement structures with longitudinal data is fraught with limitations. This paper defines and tests a measurement model of derivatives (MMOD), which is designed to assess the measurement structure of latent constructs both for analyses of between-person differences and for the analysis of change. Simulation results indicate that MMOD outperforms existing models for multivariate analysis and provides equivalent fit to data generation models. Additional simulations show MMOD capable of detecting differences in between-person and within-person factor structures. Model features, applications and future directions are discussed. PMID:24364383

  14. Use of Longitudinal Data in Genetic Studies in the Genome-wide Association Studies Era: Summary of Group 14

    PubMed Central

    Kerner, Berit; North, Kari E; Fallin, M Daniele

    2010-01-01

    Participants analyzed actual and simulated longitudinal data from the Framingham Heart Study for various metabolic and cardiovascular traits. The genetic information incorporated into these investigations ranged from selected single-nucleotide polymorphisms to genome-wide association arrays. Genotypes were incorporated using a broad range of methodological approaches including conditional logistic regression, linear mixed models, generalized estimating equations, linear growth curve estimation, growth modeling, growth mixture modeling, population attributable risk fraction based on survival functions under the proportional hazards models, and multivariate adaptive splines for the analysis of longitudinal data. The specific scientific questions addressed by these different approaches also varied, ranging from a more precise definition of the phenotype, bias reduction in control selection, estimation of effect sizes and genotype associated risk, to direct incorporation of genetic data into longitudinal modeling approaches and the exploration of population heterogeneity with regard to longitudinal trajectories. The group reached several overall conclusions: 1) The additional information provided by longitudinal data may be useful in genetic analyses. 2) The precision of the phenotype definition as well as control selection in nested designs may be improved, especially if traits demonstrate a trend over time or have strong age-of-onset effects. 3) Analyzing genetic data stratified for high-risk subgroups defined by a unique development over time could be useful for the detection of rare mutations in common multi-factorial diseases. 4) Estimation of the population impact of genomic risk variants could be more precise. The challenges and computational complexity demanded by genome-wide single-nucleotide polymorphism data were also discussed. PMID:19924713

  15. Rasch Analyses of Very Low Food Security among Households and Children in the Three City Study*

    PubMed Central

    Moffitt, Robert A.; Ribar, David C.

    2017-01-01

    The longitudinal Three City Study of low-income families with children measures food hardships using fewer questions and some different questions from the standard U.S. instrument for measuring food security, the Household Food Security Survey Module (HFSSM) in the Current Population Survey (CPS). We utilize a Rasch measurement model to identify thresholds of very low food security among households and very low food security among children in the Three City Study that are comparable to thresholds from the HFSSM. We also use the Three City Study to empirically investigate the determinants of food insecurity and of these specific food insecurity outcomes, estimating a multivariate behavioral Rasch model that is adapted to address longitudinal data. The estimation results indicate that participation in the Supplemental Nutrition Assistance Program and the Temporary Assistance for Needy Families program reduce food insecurity, while poverty and disability among caregivers increase it. Besides its longitudinal structure, the Three City Study measures many more characteristics about households than the CPS. Our estimates reveal that financial assistance through social networks and a household's own financial assets reduce food insecurity, while its outstanding loans increase insecurity. PMID:29187764

  16. Rasch Analyses of Very Low Food Security among Households and Children in the Three City Study.

    PubMed

    Moffitt, Robert A; Ribar, David C

    2016-04-01

    The longitudinal Three City Study of low-income families with children measures food hardships using fewer questions and some different questions from the standard U.S. instrument for measuring food security, the Household Food Security Survey Module (HFSSM) in the Current Population Survey (CPS). We utilize a Rasch measurement model to identify thresholds of very low food security among households and very low food security among children in the Three City Study that are comparable to thresholds from the HFSSM. We also use the Three City Study to empirically investigate the determinants of food insecurity and of these specific food insecurity outcomes, estimating a multivariate behavioral Rasch model that is adapted to address longitudinal data. The estimation results indicate that participation in the Supplemental Nutrition Assistance Program and the Temporary Assistance for Needy Families program reduce food insecurity, while poverty and disability among caregivers increase it. Besides its longitudinal structure, the Three City Study measures many more characteristics about households than the CPS. Our estimates reveal that financial assistance through social networks and a household's own financial assets reduce food insecurity, while its outstanding loans increase insecurity.

  17. Which types of mental work demands may be associated with reduced risk of dementia?

    PubMed

    Then, Francisca S; Luck, Tobias; Heser, Kathrin; Ernst, Annette; Posselt, Tina; Wiese, Birgitt; Mamone, Silke; Brettschneider, Christian; König, Hans-Helmut; Weyerer, Siegfried; Werle, Jochen; Mösch, Edelgard; Bickel, Horst; Fuchs, Angela; Pentzek, Michael; Maier, Wolfgang; Scherer, Martin; Wagner, Michael; Riedel-Heller, Steffi G

    2017-04-01

    Previous studies have demonstrated that an overall high level of mental work demands decreased dementia risk. In our study, we investigated whether this effect is driven by specific mental work demands and whether it is exposure dependent. Patients aged 75+ years were recruited from general practitioners and participated in up to seven assessment waves (every 1.5 years) of the longitudinal AgeCoDe study. Analyses of the impact of specific mental work demands on dementia risk were carried out via multivariate regression modeling (n = 2315). We observed a significantly lower dementia risk in individuals with a higher level of "information processing" (HR, 0.888), "pattern detection" (HR, 0.878), "mathematics" (HR, 0.878), and "creativity" (HR, 0.878). Yet, exposure-dependent effects were only significant for "information processing" and "pattern detection." Our longitudinal observations suggest that dementia risk may be reduced by some but not all types of mental work demands. Copyright © 2016 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

  18. Colorectal cancer screening and adverse childhood experiences: Which adversities matter?

    PubMed

    Alcalá, Héctor E; Keim-Malpass, Jessica; Mitchell, Emma

    2017-07-01

    Adverse Childhood Experiences (ACEs) have been associated with an increased risk of a variety of diseases, including cancer. However, research has not paid enough attention to the association between ACEs and cancer screening. As such, the present study examined the association between ACEs and ever using colorectal cancer (CRC) screening, among adults age 50 and over. Analyses used the 2011 Behavioral Risk Factor Surveillance System (n=24,938) to model odds of ever engaging in CRC screening from nine different adversities. Bivariate and multivariate models were fit. In bivariate models, physical abuse, having parents that were divorced or separated, and living in a household where adults treated each other violently were associated with lower odds of engaging in CRC. In multivariate models that accounted for potential confounders, emotional and sexual abuse were each associated with higher odds of engaging in CRC. Results suggest potential pathways by which early childhood experiences can impact future health behaviors. Future research should examine this association longitudinally. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. The Etiology of Variation in Language Skills Changes with Development: A Longitudinal Twin Study of Language from 2 to 12 Years

    ERIC Educational Resources Information Center

    Hayiou-Thomas, Marianna E.; Dale, Philip S.; Plomin, Robert

    2012-01-01

    The present study is the first long-term longitudinal examination of the etiology of individual differences in language from early childhood through to adolescence. We applied a multivariate latent factor genetic model to longitudinal data from the Twins Early Development Study in order to (a) compare the magnitude of genetic and environmental…

  20. Social support, social strain and inflammation: Evidence from a national longitudinal study of U.S. adults

    PubMed Central

    Yang, Yang Claire; Schorpp, Kristen; Harris, Kathleen Mullan

    2014-01-01

    Social relationships have long been held to have powerful effects on health and survival, but it remains unclear whether such associations differ by function and domain of relationships over time and what biophysiological mechanisms underlie these links. This study addressed these gaps by examining the longitudinal associations of persistent relationship quality across a ten year span with a major indicator of immune function. Specifically, we examined how perceived social support and social strain from relationships with family, friends, and spouse at a prior point in time are associated with subsequent risks of inflammation, as assessed by overall inflammation burden comprised of five markers (C-reactive protein, interleukin-6, fibrinogen, E-selectin, and intracellular adhesion molecule-1) in a national longitudinal study of 647 adults from the Midlife Development in the United States (1995–2009). Results from multivariate regression analysis show that (1) support from family, friends, and spouse modestly protected against risks of inflammation; (2) family, friend, and total social strain substantially increased risks of inflammation; and (3) the negative associations of social strain were stronger than the positive associations of social support with inflammation. The findings highlight the importance of enriched conceptualizations, measures, and longitudinal analyses of both social and biological stress processes to elucidate the complex pathways linking social relationships to health and illness. PMID:24607674

  1. Revisiting the Dedifferentiation Hypothesis with Longitudinal Multi-Cohort Data

    ERIC Educational Resources Information Center

    de Frias, Cindy M.; Lovden, Martin; Lindenberger, Ulman; Nilsson, Lars-Goran

    2007-01-01

    The present longitudinal multi-cohort study examines whether interindividual variability in cognitive performance and change increases in old age, and whether associations among developments of different cognitive functions increase with adult age. Multivariate multiple-group latent growth modeling was applied to data from narrow cohorts separated…

  2. Bayesian Methods for Scalable Multivariate Value-Added Assessment

    ERIC Educational Resources Information Center

    Lockwood, J. R.; McCaffrey, Daniel F.; Mariano, Louis T.; Setodji, Claude

    2007-01-01

    There is increased interest in value-added models relying on longitudinal student-level test score data to isolate teachers' contributions to student achievement. The complex linkage of students to teachers as students progress through grades poses both substantive and computational challenges. This article introduces a multivariate Bayesian…

  3. School-to-work program participation and the post-high school employment of young adults with disabilities

    PubMed Central

    Shandra, Carrie L.; Hogan, Dennis P.

    2014-01-01

    Previous research on the education-to-employment transition for students with disabilities has suggested that participation in school-to-work programs is positively associated with post-high school success. This article utilizes data from the National Longitudinal Survey of Youth 1997 (NLSY97) to extend these findings in several ways. First, we assess the efficacy of specific types of school-based and work-based initiatives, including job shadowing, mentoring, cooperative education, school-sponsored enterprise, technical preparation, internships, and career major. Next, we extend the usual focus on the employment outcomes of work status and financial compensation to consider job-specific information on the receipt of fringe benefits. Overall, results from longitudinal multivariate analyses suggest that transition initiatives are effective in facilitating vocational success for this population; however, different aspects of school-to-work programs are beneficial for different aspects of employment. School-based programs are positively associated with stable employment and full-time work while work-based programs most consistently increase the likelihood that youth with disabilities will be employed in jobs that provide fringe benefits. Analyses also indicate that – once individuals with disabilities are stably employed – they can be employed in “good” jobs that provide employee benefits. PMID:25309111

  4. A longitudinal examination of generic and occupational specific job demands, and work-related social support associated with burnout among nurses in Sweden.

    PubMed

    Sundin, L; Hochwälder, J; Lisspers, J

    2011-01-01

    Burnout is a familiar problem within nursing. This longitudinal study was designed to examine the roles that generic and occupational specific job demands (i.e. "pain and death", "patient and relative needs", "threats and violence", "professional worries"), and various work-related sources of support play in association with burnout in a sample of registered nurses in Sweden. A questionnaire was completed on two different occasions, by the same group of nurses from three hospitals and two primary health care centers. Nurses with initial low and moderate scores on emotional exhaustion (n=585) and depersonalization (n=631) were included in the logistic regression analyses. Initial scores, as well as four categories examining change over time in the predictors (unchanged low, improved, impaired, unchanged high), were associated with burnout approximately one year later. In the multivariate analyses, quantitative job demands and professional worries were associated with emotional exhaustion. Poor co-worker support was associated with depersonalization over time. This study suggests an association between generic as well as occupational specific job demands and emotional exhaustion. Furthermore, an association between poor co-worker support and depersonalization was suggested. Implications of these findings and recommended directions for future research are discussed.

  5. Metabolic Profiling of Adiponectin Levels in Adults: Mendelian Randomization Analysis.

    PubMed

    Borges, Maria Carolina; Barros, Aluísio J D; Ferreira, Diana L Santos; Casas, Juan Pablo; Horta, Bernardo Lessa; Kivimaki, Mika; Kumari, Meena; Menon, Usha; Gaunt, Tom R; Ben-Shlomo, Yoav; Freitas, Deise F; Oliveira, Isabel O; Gentry-Maharaj, Aleksandra; Fourkala, Evangelia; Lawlor, Debbie A; Hingorani, Aroon D

    2017-12-01

    Adiponectin, a circulating adipocyte-derived protein, has insulin-sensitizing, anti-inflammatory, antiatherogenic, and cardiomyocyte-protective properties in animal models. However, the systemic effects of adiponectin in humans are unknown. Our aims were to define the metabolic profile associated with higher blood adiponectin concentration and investigate whether variation in adiponectin concentration affects the systemic metabolic profile. We applied multivariable regression in ≤5909 adults and Mendelian randomization (using cis -acting genetic variants in the vicinity of the adiponectin gene as instrumental variables) for analyzing the causal effect of adiponectin in the metabolic profile of ≤37 545 adults. Participants were largely European from 6 longitudinal studies and 1 genome-wide association consortium. In the multivariable regression analyses, higher circulating adiponectin was associated with higher high-density lipoprotein lipids and lower very-low-density lipoprotein lipids, glucose levels, branched-chain amino acids, and inflammatory markers. However, these findings were not supported by Mendelian randomization analyses for most metabolites. Findings were consistent between sexes and after excluding high-risk groups (defined by age and occurrence of previous cardiovascular event) and 1 study with admixed population. Our findings indicate that blood adiponectin concentration is more likely to be an epiphenomenon in the context of metabolic disease than a key determinant. © 2017 The Authors.

  6. Childhood Predictors of Teen Dating Violence Victimization

    PubMed Central

    Maas, Carl D.; Fleming, Charles B.; Herrenkohl, Todd I.; Catalano, Richard F.

    2009-01-01

    Most research on predictors of teen dating violence (TDV) has used cross-sectional data, which weakens predictive modeling and hypothesis testing analyses. This study uses prospective and retrospective longitudinal data on a community sample to examine previously identified predictors of TDV victimization and pathways from childhood risk and protection to TDV victimization. Data are from 941 participants in the Raising Healthy Children project. Bivariate analyses found associations in the expected direction between potential predictors and TDV victimization. For girls, a multivariate path model indicated that higher levels of bonding to parents and social skills protected against TDV victimizations, partly by reducing early adolescent alcohol use. While externalizing and internalizing behaviors in early adolescence were predicted by childhood risk and protective factors for girls, neither uniquely predicted TDV victimization. For boys, there was an indirect path from childhood bonding to parents to TDV victimization through early adolescent externalizing behavior. PMID:20514813

  7. A Composite Likelihood Inference in Latent Variable Models for Ordinal Longitudinal Responses

    ERIC Educational Resources Information Center

    Vasdekis, Vassilis G. S.; Cagnone, Silvia; Moustaki, Irini

    2012-01-01

    The paper proposes a composite likelihood estimation approach that uses bivariate instead of multivariate marginal probabilities for ordinal longitudinal responses using a latent variable model. The model considers time-dependent latent variables and item-specific random effects to be accountable for the interdependencies of the multivariate…

  8. Multivariate-$t$ nonlinear mixed models with application to censored multi-outcome AIDS studies.

    PubMed

    Lin, Tsung-I; Wang, Wan-Lun

    2017-10-01

    In multivariate longitudinal HIV/AIDS studies, multi-outcome repeated measures on each patient over time may contain outliers, and the viral loads are often subject to a upper or lower limit of detection depending on the quantification assays. In this article, we consider an extension of the multivariate nonlinear mixed-effects model by adopting a joint multivariate-$t$ distribution for random effects and within-subject errors and taking the censoring information of multiple responses into account. The proposed model is called the multivariate-$t$ nonlinear mixed-effects model with censored responses (MtNLMMC), allowing for analyzing multi-outcome longitudinal data exhibiting nonlinear growth patterns with censorship and fat-tailed behavior. Utilizing the Taylor-series linearization method, a pseudo-data version of expectation conditional maximization either (ECME) algorithm is developed for iteratively carrying out maximum likelihood estimation. We illustrate our techniques with two data examples from HIV/AIDS studies. Experimental results signify that the MtNLMMC performs favorably compared to its Gaussian analogue and some existing approaches. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Work–family conflict and health in Swedish working women and men: a 2-year prospective analysis (the SLOSH study)

    PubMed Central

    Baltzer, Maria; Magnusson Hanson, Linda L.; Westerlund, Hugo

    2013-01-01

    Background: Research has suggested that gender is related to perceptions of work–family conflict (WFC) and an underlying assumption is that interference of paid work with family life will burden women more than men. There is, however, mixed evidence as to whether men and women report different levels of WFC. Even less studies investigate gender differences in health outcomes of WFC. Also the number of longitudinal studies in this field is low. Methods: Based on the Swedish Longitudinal Occupational Survey of Health, we prospectively examined the effects of WFC on three different health measures representing a wide spectrum off ill health (i.e. self-rated health, emotional exhaustion and problem drinking). Logistic regression analyses were used to analyse multivariate associations between WFC in 2008 and health 2 years later. Results: The results show that WFC was associated with an increased risk of emotional exhaustion among both men and women. Gender differences are suggested as WFC was related to an increased risk for poor self-rated health among women and problem drinking among men. Interaction analyses revealed that the risk of poor self-rated health was substantially more influenced by WFC among women than among men. Conclusions: We conclude that, despite the fact that women experience conflict between work and family life slightly more often than men, both men’s and women’s health is negatively affected by this phenomenon. PMID:22683777

  10. Continuity and change in the social stratification of aging and health over the life course: evidence from a nationally representative longitudinal study from 1986 to 2001/2002 (Americans' Changing Lives Study).

    PubMed

    House, James S; Lantz, Paula M; Herd, Pamela

    2005-10-01

    This article overviews previously published and ongoing research from the Americans' Changing Lives (ACL) Study, a longitudinal study of a nationally representative sample of 3,617 adults aged 25 years and older when first interviewed in 1986, focusing on socioeconomic disparities in the way health changes with age during middle and later life, especially in terms of compression of morbidity/functional limitations. A variety of descriptive and multivariate regression and growth curve analyses are done on the ACL sample, now surveyed over four waves spanning 15.5 years between 1986 and 2001/2002 with continuing mortality ascertainment via the National Death Index, death certificate searches, and informant reports. Both cross-sectional and longitudinal analyses indicate that socioeconomic disparities in health are small in early adulthood, increase through middle and early old age, and then lessen again in later old age. In other terms, compression of morbidity/functional limitations into the later stages of the life course is realized to a much greater degree among the better educated compared with the less educated. Cross-sectional evidence suggests that this reflects differential exposure to or experience of a wide range of psychosocial, environmental, and biomedical risk factors for health (and perhaps their differential impact at different ages and life stages), as well as variations in biological robustness and frailty and also perhaps in the strength of social welfare supports for health at different life stages. Longitudinal analyses reveal several new insights: (a) The flow of causality is much greater from socioeconomic position to health than vice versa; (b) education plays a greater role relative to income in the onset of functional limitations, whereas income has much stronger effects on their progression or course; and (c) educational disparities in the onset and hence of compression of functional limitations over the life course have increased strikingly in later middle and early old age (ages 55-84 years) since 1986. The results indicate that understanding and alleviating social disparities in health are both theoretically and methodologically quintessential problems of life course analysis and research.

  11. Social phobia, depression and eating disorders during middle adolescence: longitudinal associations and treatment seeking.

    PubMed

    Ranta, Klaus; Väänänen, Juha; Fröjd, Sari; Isomaa, Rasmus; Kaltiala-Heino, Riittakerttu; Marttunen, Mauri

    2017-11-01

    Longitudinal associations between social phobia (SP), depression and eating disorders (EDs), and the impact of antecedent SP and depression on subsequent treatment seeking for EDs have rarely been explored in prospective adolescent population studies. We aimed to examine these associations in a large-scale follow-up study among middle adolescents. We surveyed 3278 Finnish adolescents with a mean age of 15 years for these disorders. Two years later, 2070 were reached and again surveyed for psychopathology and treatment seeking. Longitudinal associations between the self-reported disorders and treatment-seeking patterns for self-acknowledged ED symptoms were examined in multivariate analyses, controlling for SP/depression comorbidity and relevant socioeconomic covariates. Self-reported anorexia nervosa (AN) at age 15 years predicted self-reported depression at age 17 years. Furthermore, self-reported SP at age 15 years predicted not seeking treatment for bulimia nervosa (BN) symptoms, while self-reported depression at age 15 years predicted not seeking treatment for AN symptoms during the follow-up period. Adolescents with AN should be monitored for subsequent depression. Barriers caused by SP to help seeking for BN, and by depression for AN, should be acknowledged by healthcare professionals who encounter socially anxious and depressive adolescents, especially when they present with eating problems.

  12. A Model for Teacher Effects from Longitudinal Data without Assuming Vertical Scaling

    ERIC Educational Resources Information Center

    Mariano, Louis T.; McCaffrey, Daniel F.; Lockwood, J. R.

    2010-01-01

    There is an increasing interest in using longitudinal measures of student achievement to estimate individual teacher effects. Current multivariate models assume each teacher has a single effect on student outcomes that persists undiminished to all future test administrations (complete persistence [CP]) or can diminish with time but remains…

  13. Longitudinal Associations between Sibling Relationship Qualities and Risky Behavior across Adolescence

    ERIC Educational Resources Information Center

    Solmeyer, Anna R.; McHale, Susan M.; Crouter, Ann C.

    2014-01-01

    This study examined the associations between sibling intimacy and conflict and youths' reports of risky behavior in a sample of adolescents ages 11-20. Participants were mothers, fathers, and sibling dyads in 393 families who were interviewed annually for 3, 4, or 5 years. Multivariate multilevel models tested longitudinal links between sibling…

  14. A Longitudinal Analysis of Factors Related to Survival in Old Age.

    ERIC Educational Resources Information Center

    Shahtahmasebi, Said; And Others

    1992-01-01

    Used data from a longitudinal study of elderly which began in 1979 with 534 individuals in rural North Wales to study relationship between social circumstances and longevity. Multivariate analysis demonstrated there is no prima facie evidence that survival is affected by social networks or quality of life factors. However, socioeconomic factors…

  15. Comparing Within-Person Effects from Multivariate Longitudinal Models

    ERIC Educational Resources Information Center

    Bainter, Sierra A.; Howard, Andrea L.

    2016-01-01

    Several multivariate models are motivated to answer similar developmental questions regarding within-person (intraindividual) effects between 2 or more constructs over time, yet the within-person effects tested by each model are distinct. In this article, the authors clarify the types of within-person inferences that can be made from each model.…

  16. SOCR "Motion Charts": An Efficient, Open-Source, Interactive and Dynamic Applet for Visualizing Longitudinal Multivariate Data

    ERIC Educational Resources Information Center

    Al-Aziz, Jameel; Christou, Nicolas; Dinov, Ivo D.

    2010-01-01

    The amount, complexity and provenance of data have dramatically increased in the past five years. Visualization of observed and simulated data is a critical component of any social, environmental, biomedical or scientific quest. Dynamic, exploratory and interactive visualization of multivariate data, without preprocessing by dimensionality…

  17. The impact of covariance misspecification in multivariate Gaussian mixtures on estimation and inference: an application to longitudinal modeling.

    PubMed

    Heggeseth, Brianna C; Jewell, Nicholas P

    2013-07-20

    Multivariate Gaussian mixtures are a class of models that provide a flexible parametric approach for the representation of heterogeneous multivariate outcomes. When the outcome is a vector of repeated measurements taken on the same subject, there is often inherent dependence between observations. However, a common covariance assumption is conditional independence-that is, given the mixture component label, the outcomes for subjects are independent. In this paper, we study, through asymptotic bias calculations and simulation, the impact of covariance misspecification in multivariate Gaussian mixtures. Although maximum likelihood estimators of regression and mixing probability parameters are not consistent under misspecification, they have little asymptotic bias when mixture components are well separated or if the assumed correlation is close to the truth even when the covariance is misspecified. We also present a robust standard error estimator and show that it outperforms conventional estimators in simulations and can indicate that the model is misspecified. Body mass index data from a national longitudinal study are used to demonstrate the effects of misspecification on potential inferences made in practice. Copyright © 2013 John Wiley & Sons, Ltd.

  18. Impact of sociodemographic characteristics on underemployment in a longitudinal, nationally representative study of cancer survivors: Evidence for the importance of gender and marital status.

    PubMed

    Kent, Erin E; Davidoff, Amy; de Moor, Janet S; McNeel, Timothy S; Virgo, Katherine S; Coughlan, Diarmuid; Han, Xuesong; Ekwueme, Donatus U; Guy, Gery P; Banegas, Matthew P; Alfano, Catherine M; Dowling, Emily C; Yabroff, K Robin

    2018-01-01

    We examined the longitudinal association between sociodemographic factors and an expanded definition of underemployment among those with and without cancer history in the United States. Medical Expenditure Panel Survey data (2007-2013) were used in multivariable regression analyses to compare employment status between baseline and two-year follow-up among adults aged 25-62 years at baseline (n = 1,614 with and n = 39,324 without cancer). Underemployment was defined as becoming/staying unemployed, changing from full to part-time, or reducing part-time work significantly. Interaction effects between cancer history/time since diagnosis and predictors known to be associated with employment patterns, including age, gender/marital status, education, and health insurance status at baseline were modeled. Approximately 25% of cancer survivors and 21% of individuals without cancer reported underemployment at follow-up (p = 0.002). Multivariable analyses indicated that those with a cancer history report underemployment more frequently (24.7%) than those without cancer (21.4%, p = 0.002) with underemployment rates increasing with time since cancer diagnosis. A significant interaction between gender/marital status and cancer history and underemployment was found (p = 0.0004). There were no other significant interactions. Married female survivors diagnosed >10 years ago reported underemployment most commonly (38.7%), and married men without cancer reported underemployment most infrequently (14.0%). A wider absolute difference in underemployment reports for married versus unmarried women as compared to married versus unmarried men was evident, with the widest difference apparent for unmarried versus married women diagnosed >10 years ago (18.1% vs. 38.7%). Cancer survivors are more likely to experience underemployment than those without cancer. Longer time since cancer diagnosis and gender/marital status are critical factors in predicting those at greatest risk of underemployment. The impact of cancer on work should be systematically studied across sociodemographic groups and recognized as a component of comprehensive survivorship care.

  19. Endogenous Androgens and Sex Hormone-Binding Globulin in Women and Risk of Metabolic Syndrome and Type 2 Diabetes.

    PubMed

    Fenske, Benjamin; Kische, Hanna; Gross, Stefan; Wallaschofski, Henri; Völzke, Henry; Dörr, Marcus; Nauck, Matthias; Keevil, Brian G; Brabant, Georg; Haring, Robin

    2015-12-01

    The association of endogenous androgens and sex hormone-binding globulin (SHBG) with metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM) mostly 23562 refers to small and selected study samples with immunoassay-based measurements. Thus, we investigated the association of hormone levels with MetS and T2DM in women from a large population-based sample. A total of 2077 women from the Study of Health in Pomerania were assessed at baseline (N = 3160, 1997-2001) and 5-year follow-up (N = 1711, 2002-2006). We investigated associations of total testosterone (T) and androstenedione measured by liquid chromatography-tandem mass spectrometry, SHBG by immunoassay, and free T and free androgen index with MetS and T2DM. Baseline prevalence of MetS and T2DM was 23.1% (N = 365) and 9.5% (N = 196), with an incidence of 17.7 and 7.0 per 1.000 person-years, respectively. Cross-sectional analyses yielded inverse associations of SHBG with MetS (relative risk [RR], 0.67; 95% confidence interval [CI], 0.60-0.74) and T2DM (RR, 0.61; 95% CI, 0.50-0.74) after multivariable adjustment. In longitudinal analyses, only age-adjusted models showed an inverse association of baseline SHBG with incident MetS (RR, 0.61; 95% CI, 0.51-0.73) and T2DM (RR, 0.58; 95% CI, 0.43-0.78). Multivariable-adjusted models stratified by menopausal status revealed an inverse association between SHBG and incident MetS risk in postmenopausal women (RR, 0.65; 95% CI, 0.51-0.81). This longitudinal population-based study revealed independent inverse associations of SHBG with MetS and T2DM, suggesting low SHBG as a potential risk marker for cardiometabolic morbidity, especially among postmenopausal women.

  20. Association of chronic kidney disease with abnormal cardiac mechanics and adverse outcomes in patients with heart failure and preserved ejection fraction.

    PubMed

    Unger, Erin D; Dubin, Ruth F; Deo, Rajat; Daruwalla, Vistasp; Friedman, Julie L; Medina, Crystal; Beussink, Lauren; Freed, Benjamin H; Shah, Sanjiv J

    2016-01-01

    Chronic kidney disease (CKD) is associated with worse outcomes in heart failure with preserved ejection fraction (HFpEF). Whether this association is due the effect of CKD on intrinsic abnormalities in cardiac function is unknown. We hypothesized that CKD is independently associated with worse cardiac mechanics in HFpEF. We prospectively studied 299 patients enrolled in the Northwestern University HFpEF Program. Using the creatinine-based CKD-Epi equation to calculate estimated glomerular filtration rate (eGFR), study participants were analysed by CKD status (using eGFR <60 mL/min/1.73 m(2) to denote CKD). Indices of cardiac mechanics (longitudinal strain parameters) were measured using speckle-tracking echocardiography. Using multivariable-adjusted linear and Cox regression analyses, we determined the association between CKD and echocardiographic parameters and clinical outcomes (cardiovascular hospitalization or death). Of 299 study participants, 48% had CKD. CKD (dichotomous variable) and reduced eGFR (continuous variable) were both associated with worse cardiac mechanics indices including left atrial (LA) reservoir strain, LV longitudinal strain, and right ventricular free wall strain even after adjusting for potential confounders, including co-morbidities, EF, and volume status. For example, for each 1-SD decrease in eGFR, LA reservoir strain was 3.52% units lower (P < 0.0001) after multivariable adjustment. Reduced eGFR was also associated with worse outcomes [adjusted hazard ratio (HR) 1.28, 95% confidence interval (CI) 1.01-1.61 per 1-SD decrease in eGFR; P = 0.039]. The association was attenuated after adjustment for indices of cardiac mechanics (P = 0.064). In HFpEF, CKD is independently associated with worse cardiac mechanics, which may explain why HFpEF patients with CKD have worse outcomes. NCT01030991. © 2015 The Authors European Journal of Heart Failure © 2015 European Society of Cardiology.

  1. Influence of social support on cognitive change and mortality in old age: results from the prospective multicentre cohort study AgeCoDe

    PubMed Central

    2012-01-01

    Background Social support has been suggested to positively influence cognition and mortality in old age. However, this suggestion has been questioned due to inconsistent operationalisations of social support among studies and the small number of longitudinal studies available. This study aims to investigate the influence of perceived social support, understood as the emotional component of social support, on cognition and mortality in old age as part of a prospective longitudinal multicentre study in Germany. Methods A national subsample of 2,367 primary care patients was assessed twice over an observation period of 18 months regarding the influence of social support on cognitive function and mortality. Perceived social support was assessed using the 14-item version of the FSozU, which is a standardised and validated questionnaire of social support. Cognition was tested by the neuropsychological test battery of the Structured Interview for the Diagnosis of Dementia (SIDAM). The influence of perceived support on cognitive change was analysed by multivariate ANCOVA; mortality was analysed by multivariate logistic and cox regression. Results Sample cognitive change (N = 1,869): Mean age was 82.4 years (SD 3.3) at the beginning of the observation period, 65.9% were female, mean cognition was 49 (SD 4.4) in the SIDAM. Over the observation period cognitive function declined in 47.2% by a mean of 3.4 points. Sample mortality (N = 2,367): Mean age was 82.5 years (SD 3.4), 65.7% were female and 185 patients died during the observation period. Perceived social support showed no longitudinal association with cognitive change (F = 2.235; p = 0.135) and mortality (p = 0.332; CI 0.829-1.743). Conclusions Perceived social support did not influence cognition and mortality over an 18 months observation period. However, previous studies using different operationalisations of social support and longer observation periods indicate that such an influence may exist. This influence is rather small and the result of complex interaction mechanisms between different components of social support; the emotional component seems to have no or only a limited effect. Further research is needed to describe the complex interactions between components of social support. Longer observation periods are necessary and standardised operationalisations of social support should be applied. PMID:22433223

  2. Influence of social support on cognitive change and mortality in old age: results from the prospective multicentre cohort study AgeCoDe.

    PubMed

    Eisele, Marion; Zimmermann, Thomas; Köhler, Mirjam; Wiese, Birgitt; Heser, Kathrin; Tebarth, Franziska; Weeg, Dagmar; Olbrich, Julia; Pentzek, Michael; Fuchs, Angela; Weyerer, Siegfried; Werle, Jochen; Leicht, Hanna; König, Hans-Helmut; Luppa, Melanie; Riedel-Heller, Steffi; Maier, Wolfgang; Scherer, Martin

    2012-03-20

    Social support has been suggested to positively influence cognition and mortality in old age. However, this suggestion has been questioned due to inconsistent operationalisations of social support among studies and the small number of longitudinal studies available. This study aims to investigate the influence of perceived social support, understood as the emotional component of social support, on cognition and mortality in old age as part of a prospective longitudinal multicentre study in Germany. A national subsample of 2,367 primary care patients was assessed twice over an observation period of 18 months regarding the influence of social support on cognitive function and mortality. Perceived social support was assessed using the 14-item version of the FSozU, which is a standardised and validated questionnaire of social support. Cognition was tested by the neuropsychological test battery of the Structured Interview for the Diagnosis of Dementia (SIDAM). The influence of perceived support on cognitive change was analysed by multivariate ANCOVA; mortality was analysed by multivariate logistic and cox regression. Sample cognitive change (N = 1,869): Mean age was 82.4 years (SD 3.3) at the beginning of the observation period, 65.9% were female, mean cognition was 49 (SD 4.4) in the SIDAM. Over the observation period cognitive function declined in 47.2% by a mean of 3.4 points. Sample mortality (N = 2,367): Mean age was 82.5 years (SD 3.4), 65.7% were female and 185 patients died during the observation period. Perceived social support showed no longitudinal association with cognitive change (F = 2.235; p = 0.135) and mortality (p = 0.332; CI 0.829-1.743). Perceived social support did not influence cognition and mortality over an 18 months observation period. However, previous studies using different operationalisations of social support and longer observation periods indicate that such an influence may exist. This influence is rather small and the result of complex interaction mechanisms between different components of social support; the emotional component seems to have no or only a limited effect. Further research is needed to describe the complex interactions between components of social support. Longer observation periods are necessary and standardised operationalisations of social support should be applied.

  3. Longitudinal motor development of "apparently normal" high-risk infants at 18 months, 3 and 5 years.

    PubMed

    Goyen, Traci Anne; Lui, Kei

    2002-12-01

    Motor development appears to be more affected by premature birth than other developmental domains, however few studies have specifically investigated the development of gross and fine motor skills in this population. To examine longitudinal motor development in a group of "apparently normal" high-risk infants. Developmental follow-up clinic in a perinatal centre. Longitudinal observational cohort study. Fifty-eight infants born less than 29 weeks gestation and/or 1000 g and without disabilities detected at 12 months. Longitudinal gross and fine motor skills at 18 months, 3 and 5 years using the Peabody Developmental Motor Scales. The HOME scale provided information of the home environment as a stimulus for development. A large proportion (54% at 18 months, 47% at 3 years and 64% at 5 years) of children continued to have fine motor deficits from 18 months to 5 years. The proportion of infants with gross motor deficits significantly increased over this period (14%, 33% and 81%, p<0.001), particularly for the 'micropreemies' (born <750 g). In multivariate analyses, gross motor development was positively influenced by the quality of the home environment. A large proportion of high-risk infants continued to have fine motor deficits, reflecting an underlying problem with fine motor skills. The proportion of infants with gross motor deficits significantly increased, as test demands became more challenging. In addition, the development of gross and fine motor skills appears to be influenced differently by the home environment.

  4. Correlates of smoking among youth: the role of parents, friends, attitudes/beliefs, and demographics.

    PubMed

    Dietz, Noella A; Arheart, Kristopher L; Sly, David F; Lee, David J; McClure, Laura A

    2016-01-01

    Family engagement has been shown to play a crucial role in youth cigarette use prevention and uptake. We examine cross-sectional and longitudinal data to determine whether changes in parental monitoring factors influence changes in smoking susceptibility. Two cross-sectional surveys of Florida youth (12-17 years) were conducted in 2009, with a follow-up survey in 2010. Multivariable analyses examined demographics, parent characteristics, family engagement, and parental monitoring on youth susceptibility to smoke. Cross-sectional data show eating together 6+ times/week and doing something for fun 5+ times/week were related to an increased likelihood of Very Low and decreased likelihood of High susceptibility, respectively. Parental monitoring factors and parents tell on a friend who smokes was significantly related to having Very Low susceptibility in both surveys. Mother's education, parent smokes, family engagement factors, and parental monitoring were significant in both survey rounds. Longitudinal analyses showed change in eating together did not significantly affect the odds of change in smoking susceptibility; however, change in the frequency of doing things for fun with a parent showed decreased odds of susceptibility (OR = .63 [.49-.82]), opposite of the hypothesized direction. Lastly, as youth aged, they were more likely to experience a greater odds of decreased susceptibility (OR14-15y = 1.47 [1.08-1.99] and OR≥16y = 1.40 [1.05-1.84], respectively) and less likely to experience an increased odds of susceptibility (OR14-15y = .65 [.49-.86] and OR≥16y = .72 [.56-.93], respectively). We found mixed results for family engagement and parental monitoring on changes in youth smoking susceptibility. Cross-sectional data showed general associations in the expected direction; however, longitudinal analyses showed family engagement variables had significance, but in the opposite hypothesized direction.

  5. Analyzing Multiple Outcomes in Clinical Research Using Multivariate Multilevel Models

    PubMed Central

    Baldwin, Scott A.; Imel, Zac E.; Braithwaite, Scott R.; Atkins, David C.

    2014-01-01

    Objective Multilevel models have become a standard data analysis approach in intervention research. Although the vast majority of intervention studies involve multiple outcome measures, few studies use multivariate analysis methods. The authors discuss multivariate extensions to the multilevel model that can be used by psychotherapy researchers. Method and Results Using simulated longitudinal treatment data, the authors show how multivariate models extend common univariate growth models and how the multivariate model can be used to examine multivariate hypotheses involving fixed effects (e.g., does the size of the treatment effect differ across outcomes?) and random effects (e.g., is change in one outcome related to change in the other?). An online supplemental appendix provides annotated computer code and simulated example data for implementing a multivariate model. Conclusions Multivariate multilevel models are flexible, powerful models that can enhance clinical research. PMID:24491071

  6. Causes and Consequences of Missing Health-Related Quality of Life Assessments in Patients Who Undergo Mechanical Circulatory Support Implantation: Insights From INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support).

    PubMed

    Grady, Kathleen L; Jones, Philip G; Cristian-Andrei, Adin; Naftel, David C; Myers, Susan; Dew, Mary Amanda; Idrissi, Katharine; Weidner, Gerdi; Wissman, Sherri A; Kirklin, James K; Spertus, John A

    2017-12-01

    Missing health-related quality of life (HRQOL) data in longitudinal studies can reduce precision and power and bias results. Using INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support), we sought to identify factors associated with missing HRQOL data, examine the impact of these factors on estimated HRQOL assuming missing at random missingness, and perform sensitivity analyses to examine missing not at random (MNAR) missingness because of illness severity. INTERMACS patients (n=3248) with a preimplantation profile of 1 (critical cardiogenic shock) or 2 (progressive decline) were assessed with the EQ-5D-3L visual analog scale and Kansas City Cardiomyopathy Questionnaire-12 summary scores pre-implantation and 3 months postoperatively. Mean and median observed and missing at random-imputed HRQOL scores were calculated, followed by sensitivity analyses. Independent factors associated with HRQOL scores and missing HRQOL assessments were determined using multivariable regression. Independent factors associated with preimplantation and 3-month HRQOL scores, and with the likelihood of missing HRQOL assessments, revealed few correlates of HRQOL and missing assessments ( R 2 range, 4.7%-11.9%). For patients with INTERMACS profiles 1 and 2 and INTERMACS profile 1 alone, missing at random-imputed mean and median HRQOL scores were similar to observed scores, before and 3 months after implantation, whereas MNAR-imputed mean scores were lower (≥5 points) at baseline but not at 3 months. We recommend use of sensitivity analyses using an MNAR imputation strategy for longitudinal studies when missingness is attributable to illness severity. Conduct of MNAR sensitivity analyses may be less critical after mechanical circulatory support implant, when there are likely fewer MNAR data. © 2017 American Heart Association, Inc.

  7. Physical Activity, Physical Fitness and Leukocyte Telomere Length: the Cardiovascular Health Study.

    PubMed Central

    Soares-Miranda, Luisa; Imamura, Fumiaki; Siscovick, David; Jenny, Nancy Swords; Fitzpatrick, Annette L; Mozaffarian, Dariush

    2015-01-01

    Introduction The influence of physical activity (PA) and physical fitness (PF) at older ages on changes in telomere length (TL), repetitive DNA sequences that may mark biologic aging, is not well-established. Few prior studies have been conducted in older adults, these were mainly cross-sectional, and few evaluated PF. Methods We investigated cross-sectional and prospective associations of PA and PF with leukocyte TL among 582 older adults (age 73±5 y at baseline) in the Cardiovascular Health Study, having serial TL measures and PA and PF assessed multiple times. Cross-sectional associations were assessed using multivariable repeated-measures regression, in which cumulatively averaged PA and PF measures were related to TL. Longitudinal analyses assessed cumulatively averaged PA and PF against later changes in TL; and changes in cumulatively averaged PA and PF against changes in TL. Results Cross-sectionally, greater walking distance and chair test performance, but not other PA and PF measures, were each associated with longer TL (p-trend=0.007, 0.04 respectively). In longitudinal analyses, no significant associations of baseline PA and PF with change in TL were observed. In contrast, changes in leisure-time activity and chair test performance were each inversely associated with changes in TL. Conclusions Cross-sectional analyses suggest that greater PA and PF are associated with longer TL. Prospective analyses show that changes in PA and PF are associated with differences in changes in TL. Even later in life, changes in certain PA and PF measures are associated with changes in TL, suggesting that leisure-time activity and fitness could reduce leukocyte telomere attrition among older adults. PMID:26083773

  8. Differences in self-monitored, blood glucose test strip utilization by therapy for type 2 diabetes mellitus.

    PubMed

    Tavares, Ruben; Duclos, Marc; Brabant, Marie-Josée; Checchin, Daniella; Bosnic, Nevzeta; Turvey, Katherine; Terres, Jorge Alfonso Ross

    2016-06-01

    To determine whether blood glucose test strip (BGTS) utilization in patients with type 2 diabetes (T2D) is associated with the type of diabetes therapy, classified according to hypoglycemic risk. A retrospective, longitudinal (2006-2012) study of Canadian private drug plans (PDP) and Ontario Public Drug Programs (OPDP) prescription claims was conducted. Analyses were restricted to patients with T2D with or without a claim for BGTS. Daily BGTS utilization (TS/patient/day) was evaluated by diabetes therapy classified by hypoglycemic risk. Multivariate analyses were conducted to identify determinants of BGTS utilization. The T2D cohort comprised 5,759,591 observations from 1,949,129 claimants. Mean BGTS utilization was 0.84 TS/patient/day and differed between PDP and OPDP (0.66 vs. 1.00). Daily utilization was greatest in patients receiving therapy associated with a pre-defined high risk of hypoglycemia [insulin: basal + bolus (2.16), premixed (1.65), basal (1.16), other insulin regimens (2.13), and sulfonylureas (0.74)] versus non-sulfonylurea non-insulin-based regimens (0.52). For non-insulin therapy, BGTS utilization was greater for patients on multiple non-insulin therapies versus monotherapy (0.74 vs. 0.53 TS/patient/day). In multivariate analyses, drivers for BGTS utilization included insulin use, previous BGTS use, and female gender. Previous diabetes therapy and duration of therapy were negatively correlated with BGTS utilization. BGTS utilization varies depending on the type of therapy used to treat T2D according to hypoglycemic risk. Decision making regarding BGTS needs to account for robust analyses of current utilization and its value in those settings, including in patients not receiving diabetes therapy and the prevalence of circumstances conducive to more intensive monitoring.

  9. Parenting style and obesity risk in children.

    PubMed

    Kakinami, Lisa; Barnett, Tracie A; Séguin, Louise; Paradis, Gilles

    2015-06-01

    Parents play a critical role in their children's lifestyle habits. The objective was to assess the effect of parenting style on the risk of childhood obesity, and to determine whether poverty was a moderator of the association. Participants were from the 1994-2008 cross-sectional samples of the National Longitudinal Survey of Children and Youth (NLSCY), a nationally representative survey of Canadian youth. Factor and cluster analyses identified four parenting styles consistent with Baumrind's parenting style prototypes. Multivariable logistic regression assessed the risk of obesity based on parenting style after adjusting for covariates. Analyses were stratified by age (preschool: 2-5years of age, n=19,026; school-age: 6-11years of age, n=18,551) and the moderating effect of poverty (household income

  10. Global longitudinal strain corrected by RR interval is a superior predictor of all-cause mortality in patients with systolic heart failure and atrial fibrillation.

    PubMed

    Modin, Daniel; Sengeløv, Morten; Jørgensen, Peter Godsk; Bruun, Niels Eske; Olsen, Flemming Javier; Dons, Maria; Fritz Hansen, Thomas; Jensen, Jan Skov; Biering-Sørensen, Tor

    2018-04-01

    Quantification of systolic function in patients with atrial fibrillation (AF) is challenging. A novel approach, based on RR interval correction, to counteract the varying heart cycle lengths in AF has recently been proposed. Whether this method is superior in patients with systolic heart failure (HFrEF) with AF remains unknown. This study investigates the prognostic value of RR interval-corrected peak global longitudinal strain {GLSc = GLS/[RR^(1/2)]} in relation to all-cause mortality in HFrEF patients displaying AF during echocardiographic examination. Echocardiograms from 151 patients with HFrEF and AF during examination were analysed offline. Peak global longitudinal strain (GLS) was averaged from 18 myocardial segments obtained from three apical views. GLS was indexed with the square root of the RR interval {GLSc = GLS/[RR^(1/2)]}. Endpoint was all-cause mortality. During a median follow-up of 2.7 years, 40 patients (26.5%) died. Neither uncorrected GLS (P = 0.056) nor left ventricular ejection fraction (P = 0.053) was significantly associated with all-cause mortality. After RR^(1/2) indexation, GLSc became a significant predictor of all-cause mortality (hazard ratio 1.16, 95% confidence interval 1.02-1.22, P = 0.014, per %/s^(1/2) decrease). GLSc remained an independent predictor of mortality after multivariable adjustment (age, sex, mean heart rate, mean arterial blood pressure, left atrial volume index, and E/e') (hazard ratio 1.17, 95% confidence interval 1.05-1.31, P = 0.005 per %/s^(1/2) decrease). Decreasing {GLSc = GLS/[RR^(1/2)]}, but not uncorrected GLS nor left ventricular ejection fraction, was significantly associated with increased risk of all-cause mortality in HFrEF patients with AF and remained an independent predictor after multivariable adjustment. © 2017 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.

  11. [Change settings for visual analyzer of child users of mobile communication: longitudinal study].

    PubMed

    Khorseva, N I; Grigor'ev, Iu G; Gorbunova, N V

    2014-01-01

    The paper represents theresults of longitudinal monitoring of the changes in the parameters of simple visual-motor reaction, the visual acuity and the rate of the visual discrimination in the child users of mobile communication, which indicate the multivariability of the possible effects of radiation from mobile phones on the auditory system of children.

  12. Adolescent self-concept and health into adulthood.

    PubMed

    Park, Jungwee

    2003-01-01

    This article examines factors associated with adolescent self-concept and the impact of adolescent self-concept on psychological and physical health and health behaviour in young adulthood. The data are from the household cross-sectional (1994/95) and longitudinal (1994/95 to 2000/01) components of Statistics Canada's National Population Health Survey. Scores on self-concept indicators in 1994/95 were compared between the sexes and age groups (12 to 15 versus 16 to 19). Multivariate analyses were used to examine cross-sectional and longitudinal associations between adolescent self-concept and depression, self-perceived health, physical activity and obesity, controlling for other possible confounders. Self-concept tends to be low among girls compared with boys. Cross-sectionally, adolescent self-concept was associated with household income and emotional support. For girls and for young adolescents, a weak self-concept in 1994/95 was related to the incidence of depression over the next six years; it was also predictive of physical inactivity among boys, and obesity among both sexes. A strong self-concept had a positive long-term effect on girls' self-perceived health.

  13. Long-term health outcomes of work-related injuries among construction workers--findings from the National Longitudinal Survey of Youth.

    PubMed

    Dong, Xiuwen Sue; Wang, Xuanwen; Largay, Julie A; Sokas, Rosemary

    2015-03-01

    This study examined the relationship between work-related injuries and health outcomes among a cohort of blue-collar construction workers. Data were from the National Longitudinal Survey of Youth, 1979 cohort (NLSY79; n = 12,686). A range of health outcomes among blue-collar construction workers (n = 1,435) were measured when they turned age 40 (1998-2006) and stratified by these workers' prior work-related injury status between 1988 and 2000. Univariate and multivariate analyses were conducted to measure differences among subgroups. About 38% of the construction cohort reported injuries resulting in days away from work (DAFW); another 15% were injured but reported no DAFW (NDAFW). At age 40, an average of 10 years after injury, those with DAFW injury had worse self-reported general health and mental health, and more diagnosed conditions and functional limitations than those without injury. This difference was statistically significant after controlling for major demographics. Adverse health effects from occupational injury among construction workers persist longer than previously documented. © 2015 Wiley Periodicals, Inc.

  14. Use of Health Care Claims Data to Study Patients with Ophthalmologic Conditions

    PubMed Central

    Stein, Joshua D.; Lum, Flora; Lee, Paul P.; Rich, William L.; Coleman, Anne L.

    2014-01-01

    Objective To describe what information is or is not included in health care claims data, provide an overview of the main advantages and limitations of performing analyses using health care claims data, and offer general guidance on how to report and interpret findings of ophthalmology-related claims data analyses. Design Systematic review. Participants Not applicable. Methods A literature review and synthesis of methods for claims-based data analyses. Main Outcome Measures Not applicable. Results Some advantages of using claims data for analyses include large, diverse sample sizes, longitudinal follow-up, lack of selection bias, and potential for complex, multivariable modeling. The disadvantages include (a) the inherent limitations of claims data, such as incomplete, inaccurate, or missing data, or the lack of specific billing codes for some conditions; and (b) the inability, in some circumstances, to adequately evaluate the appropriateness of care. In general, reports of claims data analyses should include clear descriptions of the following methodological elements: the data source, the inclusion and exclusion criteria, the specific billing codes used, and the potential confounding factors incorporated in the multivariable models. Conclusions The use of claims data for research is expected to increase with the enhanced availability of data from Medicare and other sources. The use of claims data to evaluate resource use and efficiency and to determine the basis for supplementary payment methods for physicians is anticipated. Thus, it will be increasingly important for eye care providers to use accurate and descriptive codes for billing. Adherence to general guidance on the reporting of claims data analyses, as outlined in this article, is important to enhance the credibility and applicability of findings. Guidance on optimal ways to conduct and report ophthalmology-related investigations using claims data will likely continue to evolve as health services researchers refine the metrics to analyze large administrative data sets. PMID:24433971

  15. Association of Serum Thyrotropin with Anthropometric Markers of Obesity in the General Population.

    PubMed

    Tiller, Daniel; Ittermann, Till; Greiser, Karin H; Meisinger, Christa; Agger, Carsten; Hofman, Albert; Thuesen, Betina; Linneberg, Allan; Peeters, Robin; Franco, Oscar; Heier, Margit; Kluttig, Alexander; Werdan, Karl; Stricker, Bruno; Schipf, Sabine; Markus, Marcello; Dörr, Marcus; Völzke, Henry; Haerting, Johannes

    2016-09-01

    Except from associations study with body weight, there are few longitudinal data regarding the association between thyroid function and anthropometric measurements such as waist circumference, waist-to-hip ratio, or waist-to height ratio. This study aimed to investigate the association of thyrotropin (TSH) at baseline with changes in different anthropometric markers between baseline and follow-up in the general population. Data were used from four population-based longitudinal cohort studies and one population-based cross-sectional study. A total of 16,902 (8204 males) subjects aged 20-95 years from the general population were studied. Body mass index, waist circumference, waist-to-hip ratio, and waist-to-height ratio were measured. Multivariable median regression models were calculated adjusting for the following covariates: age, sex, baseline value of the respective anthropometric marker, smoking status, follow-up-time period, and study site. In cross-sectional analyses, serum TSH within the reference range was positively associated with waist circumference (β = 0.94 cm [confidence interval (CI) 0.56-1.32]) and waist-to-height-ratio (β = 0.029 [CI 0.017-0.042]). These associations were also present for the full range of TSH. In the longitudinal analyses, serum TSH at baseline was inversely associated with a five-year change of all considered anthropometric measures within the prior defined study-specific reference range, as well as in the full range of serum TSH. High TSH serum levels were positively associated with current anthropometric markers, even in the study-specific reference ranges. In contrast, high TSH serum levels were associated with decreased anthropometric markers over a time span of approximately five years. Further research is needed to determine possible clinical implications as well as public health consequences of these findings.

  16. Determinants of the prevalence and incidence of overweight in children and adolescents.

    PubMed

    Plachta-Danielzik, Sandra; Landsberg, Beate; Johannsen, Maike; Lange, Dominique; Müller, Manfred James

    2010-11-01

    To systematically analyse determinants of overweight prevalence and incidence in children and adolescents, as a basis of treatment and prevention. Cross-sectional and longitudinal data of the Kiel Obesity Prevention Study (KOPS). Schools in Kiel, Germany. Cross-sectional data from 6249 students aged 5-16 years and 4-year longitudinal data from 1087 children aged 5-11 years. Weight status of students was assessed and familial factors (weight status of parents and siblings, smoking habits), social factors (socio-economic status, nationality, single parenting), birth weight as well as lifestyle variables (physical activity, media time, nutrition) were considered as independent variables in multivariate logistic regression analyses to predict the likelihood of the student being overweight. The cross-sectional data revealed the prevalence of overweight as 18·3 % in boys and 19·2 % in girls. In both sexes determinants of overweight prevalence were overweight and obese parents, overweight siblings, parental smoking, single parenthood and non-German nationality. High birth weight and low physical activity additionally increased the risk in boys. High media time and low parental education were significant determinants in girls. Effect of media time was mediated by maternal weight status in boys as well as by socio-economic status and age in girls. From the longitudinal data, the 4-year cumulative incidence of overweight was 10·0 % in boys and 8·2 % in girls. Parental obesity, parental smoking and low physical activity were determinants of overweight incidence in boys, whereas paternal obesity increased the risk in girls. Treatment and prevention should address family and social determinants with a focus on physical activity and media use.

  17. Structural Determinants of Inconsistent Condom Use with Clients Among Migrant Sex Workers: Findings of Longitudinal Research in an Urban Canadian Setting

    PubMed Central

    Sou, Julie; Shannon, Kate; Li, Jane; Nguyen, Paul; Strathdee, Steffanie; Shoveller, Jean; Goldenberg, Shira M.

    2015-01-01

    Background Migrant women in sex work experience unique risks and protective factors related to their sexual health. Given the dearth of knowledge in high-income countries, we explored factors associated with inconsistent condom use by clients among migrant female sex workers over time in Vancouver, BC. Methods Questionnaire and HIV/STI testing data from a longitudinal cohort, AESHA, were collected from 2010–2013. Logistic regression using generalized estimating equations (GEE) was used to model correlates of inconsistent condom use by clients among international migrant sex workers over a 3-year study period. Results Of 685 participants, analyses were restricted to 182 (27%) international migrants who primarily originated from China. In multivariate GEE analyses, difficulty accessing condoms (Adjusted Odds Ratio (AOR) 3.76, 95% Confidence Interval (CI) 1.13–12.47) independently correlated with increased odds of inconsistent condom use by clients. Servicing clients in indoor sex work establishments (e.g., massage parlours) (AOR 0.34, 95% CI 0.15–0.77), and high school attainment (AOR 0.22, 95% CI 0.09–0.50) had independent protective effects on the odds of inconsistent condom use by clients. Conclusions Findings of this longitudinal study highlight the persistent challenges faced by migrant sex workers in terms of accessing and using condoms. Migrant sex workers who experienced difficulty in accessing condoms were more than three times as likely to report inconsistent condom use by clients. Laws, policies and programs promoting access to safer, decriminalized indoor work environments remain urgently needed to promote health, safety and human rights for migrant workers in the sex industry. PMID:25970307

  18. Socioeconomic Position Is Associated With Carotid Intima-Media Thickness in Mid-Childhood: The Longitudinal Study of Australian Children.

    PubMed

    Liu, Richard S; Mensah, Fiona K; Carlin, John; Edwards, Ben; Ranganathan, Sarath; Cheung, Michael; Dwyer, Terence; Saffery, Richard; Magnussen, Costan G; Juonala, Markus; Wake, Melissa; Burgner, David P

    2017-08-09

    Lower socioeconomic position (SEP) predicts higher cardiovascular risk in adults. Few studies differentiate between neighborhood and family SEP or have repeated measures through childhood, which would inform understanding of potential mechanisms and the timing of interventions. We investigated whether neighborhood and family SEP, measured biennially from ages 0 to 1 year onward, was associated with carotid intima-media thickness (IMT) at ages 11 to 12 years. Data were obtained from 1477 families participating in the Child Health CheckPoint study, nested within the Longitudinal Study of Australian Children. Disadvantaged family and neighborhood SEP was cross-sectionally associated with thicker maximum carotid IMT in separate univariable linear regression models. Associations with family SEP were not attenuated in multivariable analyses, and associations with neighborhood SEP were attenuated only in models adjusted for family SEP. The difference in maximum carotid IMT between the highest and lowest family SEP quartile measured at ages 10 to 11 years was 10.7 μm (95% CI, 3.4-18.0; P =0.004), adjusted for age, sex, pubertal status, passive smoking exposure, body mass index, blood pressure, and arterial lumen diameter. In longitudinal analyses, family SEP measured as early as age 2 to 3 years was associated with maximum carotid IMT at ages 11 to 12 years (difference between highest and lowest quartile: 8.5 μm; 95% CI, 1.3-15.8; P =0.02). No associations were observed between SEP and mean carotid IMT. We report a robust association between lower SEP in early childhood and carotid IMT in mid-childhood. Further investigation of mechanisms may inform pediatric cardiovascular risk assessment and prevention strategies. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  19. Structural determinants of inconsistent condom use with clients among migrant sex workers: findings of longitudinal research in an urban canadian setting.

    PubMed

    Sou, Julie; Shannon, Kate; Li, Jane; Nguyen, Paul; Strathdee, Steffanie A; Shoveller, Jean; Goldenberg, Shira M

    2015-06-01

    Migrant women in sex work experience unique risks and protective factors related to their sexual health. Given the dearth of knowledge in high-income countries, we explored factors associated with inconsistent condom use by clients among migrant female sex workers over time in Vancouver, BC. Questionnaire and HIV/sexually transmitted infection testing data from a longitudinal cohort, An Evaluation of Sex Workers Health Access, were collected from 2010 to 2013. Logistic regression using generalized estimating equations was used to model correlates of inconsistent condom use by clients among international migrant sex workers over a 3-year study period. Of 685 participants, analyses were restricted to 182 (27%) international migrants who primarily originated from China. In multivariate generalized estimating equations analyses, difficulty accessing condoms (adjusted odds ratio [AOR], 3.76; 95% confidence interval [CI], 1.13-12.47) independently correlated with increased odds of inconsistent condom use by clients. Servicing clients in indoor sex work establishments (e.g., massage parlors) (AOR, 0.34; 95% CI, 0.15-0.77), and high school attainment (AOR, 0.22; 95% CI, 0.09-0.50) had independent protective effects on the odds of inconsistent condom use by clients. Findings of this longitudinal study highlight the persistent challenges faced by migrant sex workers in terms of accessing and using condoms. Migrant sex workers who experienced difficulty in accessing condoms were more than 3 times as likely to report inconsistent condom use by clients. Laws, policies, and programs promoting access to safer, decriminalized indoor work environments remain urgently needed to promote health, safety, and human rights for migrant workers in the sex industry.

  20. A multivariate model exploring the predictive value of demographic, adolescent, and family factors on glycemic control in adolescents with type 1 diabetes.

    PubMed

    Agarwal, Shivani; Jawad, Abbas F; Miller, Victoria A

    2016-11-01

    The current study examined how a comprehensive set of variables from multiple domains, including at the adolescent and family level, were predictive of glycemic control in adolescents with type 1 diabetes (T1D). Participants included 100 adolescents with T1D ages 10-16 yrs and their parents. Participants were enrolled in a longitudinal study about youth decision-making involvement in chronic illness management of which the baseline data were available for analysis. Bivariate associations with glycemic control (HbA1C) were tested. Hierarchical linear regression was implemented to inform the predictive model. In bivariate analyses, race, family structure, household income, insulin regimen, adolescent-reported adherence to diabetes self-management, cognitive development, adolescent responsibility for T1D management, and parent behavior during the illness management discussion were associated with HbA1c. In the multivariate model, the only significant predictors of HbA1c were race and insulin regimen, accounting for 17% of the variance. Caucasians had better glycemic control than other racial groups. Participants using pre-mixed insulin therapy and basal-bolus insulin had worse glycemic control than those on insulin pumps. This study shows that despite associations of adolescent and family-level variables with glycemic control at the bivariate level, only race and insulin regimen are predictive of glycemic control in hierarchical multivariate analyses. This model offers an alternative way to examine the relationship of demographic and psychosocial factors on glycemic control in adolescents with T1D. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Volunteering is associated with increased survival in able-bodied participants of the English Longitudinal Study of Ageing

    PubMed Central

    Rogers, Nina Trivedy; Demakakos, Panayotes; Taylor, Mark Steven; Steptoe, Andrew; Hamer, Mark; Shankar, Aparna

    2018-01-01

    Background Volunteering has been linked to reduced mortality in older adults but the mechanisms explaining this effect remain unclear. This study investigated whether volunteering is associated with increased survival in participants of the English Longitudinal Study of Ageing and whether differences in survival are modified by functional disabilities. Methods A multivariate Cox Proportional Hazards model was used to estimate the association of volunteering with survival over a period of 10.9 years in 10,324 participants, whilst controlling for selected confounders. To investigate effect modification by disability, the analyses were repeated in participants with and without self-reported functional disabilities. Results Volunteering was associated with a reduced probability of death from all-causes in univariate analyses (HR = 0.65, CI 0.58–0.73, P < 0.0001), but adjustment for covariates rendered this association non-significant (HR = 0.90, CI 0.79–1.01, P = 0.07). Able-bodied volunteers had significantly increased survival compared to able-bodied non-volunteers (HR = 0.81, 95% CI: 0.69 – 0.95, P = 0.009). There was no significant survival advantage among disabled volunteers, compared to disabled non-volunteers (HR = 1.06, CI 0.88–1.29, P = 0.53). Conclusion Volunteering is associated with reduced mortality in older adults in England, but this effect appears to be limited to volunteers who report no disabilities. PMID:26811548

  2. [Consumption of free sugars and excess weight in infants. A longitudinal study].

    PubMed

    Jardí, Cristina; Aranda, Núria; Bedmar, Cristina; Ribot, Blanca; Elias, Irene; Aparicio, Estefania; Arija, Victoria

    2018-05-14

    The consumption of free sugars has been related to excess weight, with the WHO recommending an intake of <10% of total energy. The aim of this study is to assess the association between the consumption of free sugars at 12 months and the risk of excess weight at 30 months in healthy children. A longitudinal study was conducted on 81 children followed-up from birth to 30 months. A record was made of the clinical history and anthropometry, at birth, and at 12 and 30 months. Weight status was classified as with or without excess weight, according to WHO values. At 12 months, the intake of energy and nutrients was analysed by differentiating the intake of free and natural sugars. Multivariate analyses adjusted for the main confounding variables were performed. Free sugars were consumed by 40.4% of the 12-month-old children, being higher than that recommended, and being significantly higher in children with excess weight at 30 months (60.9%). The higher intake of free sugars at 12 months is associated with an increased risk of excess weight at 30 months (OR: 1.130, 95% CI: 1.032-1.238). The consumption of free sugars is much higher than that recommended in 12-month-old infants. This high intake could be a risk factor for excess weight, even at early ages. Copyright © 2018. Publicado por Elsevier España, S.L.U.

  3. Work functioning trajectories in cancer patients: Results from the longitudinal Work Life after Cancer (WOLICA) study.

    PubMed

    Dorland, Heleen F; Abma, Femke I; Roelen, Corné A M; Stewart, Roy E; Amick, Benjamin C; Ranchor, Adelita V; Bültmann, Ute

    2017-11-01

    More than 60% of cancer patients are able to work after cancer diagnosis. However, little is known about their functioning at work. Therefore, the aims of this study were to (1) identify work functioning trajectories in the year following return to work (RTW) in cancer patients and (2) examine baseline sociodemographic, health-related and work-related variables associated with work functioning trajectories. This longitudinal cohort study included 384 cancer patients who have returned to work after cancer diagnosis. Work functioning was measured at baseline, 3, 6, 9 and 12 months follow-up. Latent class growth modeling (LCGM) was used to identify work functioning trajectories. Associations of baseline variables with work functioning trajectories were examined using univariate and multivariate analyses. LCGM analyses with cancer patients who completed on at least three time points the Work Role Functioning Questionnaire (n = 324) identified three work functioning trajectories: "persistently high" (16% of the sample), "moderate to high" (54%) and "persistently low" work functioning (32%). Cancer patients with persistently high work functioning had less time between diagnosis and RTW and had less often a changed meaning of work, while cancer patients with persistently low work functioning reported more baseline cognitive symptoms compared to cancer patients in the other trajectories. This knowledge has implications for cancer care and guidance of cancer patients at work. © 2017 UICC.

  4. Cross-Sectional and Longitudinal Investigation of the Power Vector in Astigmatism: The Yamagata Study (Funagata).

    PubMed

    Namba, Hiroyuki; Kawasaki, Ryo; Sugano, Akira; Nishi, Katsuhiro; Murakami, Takanori; Nishitsuka, Koichi; Kato, Takeo; Kayama, Takamasa; Yamashita, Hidetoshi

    2018-01-01

    To investigate how age and other factors affect astigmatism in Japanese adults over a period of 5 years. We included 512 Japanese participants who had undergone systemic and ophthalmological examinations both in 2005-2007 and in 2010-2012 in Funagata town, Yamagata, Japan. Astigmatism was evaluated using power vector analyses, where J0 represents the power of orthogonal astigmatism. Positive values of J0 indicate with-the-rule astigmatism, whereas negative values indicate against-the-rule (ATR). In this cross-sectional investigation, J0 represented the power of orthogonal astigmatism, and multivariate regression revealed that both J0 and corneal J0 (cJ0) declined with increasing age (both P < 0.001). In a longitudinal investigation spanning 5 years, the mean amounts of change (Δ) in J0 and ΔcJ0 were -0.045 ± 0.308 and -0.072 ± 0.278, respectively. This confirmed an ATR shift with increasing age in most individuals. The age-divided distribution of the magnitude of differences indicated that older age was associated with a larger astigmatic change over a 5-year period in both the cornea and the entire eye. Using multivariate logistic regression, we observed that older age at baseline was a risk factor for low ΔJ0, indicating a large shift toward ATR astigmatism. We confirmed that a refractive and keratometric shift toward ATR astigmatism occurs with aging. Older age at baseline was also associated with a larger magnitude of astigmatic changes over the subsequent 5 years.

  5. More insights into early brain development through statistical analyses of eigen-structural elements of diffusion tensor imaging using multivariate adaptive regression splines

    PubMed Central

    Chen, Yasheng; Zhu, Hongtu; An, Hongyu; Armao, Diane; Shen, Dinggang; Gilmore, John H.; Lin, Weili

    2013-01-01

    The aim of this study was to characterize the maturational changes of the three eigenvalues (λ1 ≥ λ2 ≥ λ3) of diffusion tensor imaging (DTI) during early postnatal life for more insights into early brain development. In order to overcome the limitations of using presumed growth trajectories for regression analysis, we employed Multivariate Adaptive Regression Splines (MARS) to derive data-driven growth trajectories for the three eigenvalues. We further employed Generalized Estimating Equations (GEE) to carry out statistical inferences on the growth trajectories obtained with MARS. With a total of 71 longitudinal datasets acquired from 29 healthy, full-term pediatric subjects, we found that the growth velocities of the three eigenvalues were highly correlated, but significantly different from each other. This paradox suggested the existence of mechanisms coordinating the maturations of the three eigenvalues even though different physiological origins may be responsible for their temporal evolutions. Furthermore, our results revealed the limitations of using the average of λ2 and λ3 as the radial diffusivity in interpreting DTI findings during early brain development because these two eigenvalues had significantly different growth velocities even in central white matter. In addition, based upon the three eigenvalues, we have documented the growth trajectory differences between central and peripheral white matter, between anterior and posterior limbs of internal capsule, and between inferior and superior longitudinal fasciculus. Taken together, we have demonstrated that more insights into early brain maturation can be gained through analyzing eigen-structural elements of DTI. PMID:23455648

  6. A Study of Ontogenetic and Generational Change in Adolescent Personality by Means of Multivariate Longitudinal Sequences: Phase II. Final Report.

    ERIC Educational Resources Information Center

    Nesselroade, John R.; Baltes, Paul B.

    Assessment of the relationship between ontogenetic (individual) and generational (historical) change in adolescent personality development was the focus of this study. The total sample included 1000 male and female adolescents (ages 13-18) randomly drawn from 32 public school systems in West Virginia following a design using longitudinal sequences…

  7. Investigation of 2‐stage meta‐analysis methods for joint longitudinal and time‐to‐event data through simulation and real data application

    PubMed Central

    Tudur Smith, Catrin; Gueyffier, François; Kolamunnage‐Dona, Ruwanthi

    2017-01-01

    Background Joint modelling of longitudinal and time‐to‐event data is often preferred over separate longitudinal or time‐to‐event analyses as it can account for study dropout, error in longitudinally measured covariates, and correlation between longitudinal and time‐to‐event outcomes. The joint modelling literature focuses mainly on the analysis of single studies with no methods currently available for the meta‐analysis of joint model estimates from multiple studies. Methods We propose a 2‐stage method for meta‐analysis of joint model estimates. These methods are applied to the INDANA dataset to combine joint model estimates of systolic blood pressure with time to death, time to myocardial infarction, and time to stroke. Results are compared to meta‐analyses of separate longitudinal or time‐to‐event models. A simulation study is conducted to contrast separate versus joint analyses over a range of scenarios. Results Using the real dataset, similar results were obtained by using the separate and joint analyses. However, the simulation study indicated a benefit of use of joint rather than separate methods in a meta‐analytic setting where association exists between the longitudinal and time‐to‐event outcomes. Conclusions Where evidence of association between longitudinal and time‐to‐event outcomes exists, results from joint models over standalone analyses should be pooled in 2‐stage meta‐analyses. PMID:29250814

  8. Ecstasy use and depression: a 4-year longitudinal study among an Australian general community sample.

    PubMed

    George, Amanda M; Olesen, Sarah; Tait, Robert J

    2013-10-01

    Longitudinal, population-based studies can better assess the relationship of ecstasy use with depression. We examined whether change in ecstasy use was associated with change in depressive symptoms/probable depression over a 4-year period, among a large Australian sample. The Personality and Total Health project is a longitudinal general community study of Australians from Canberra and Queanbeyan. Data from the youngest cohort when aged 24-30 (N = 2, 128) and 4 years later (N = 1, 977) was included. The Goldberg depression scale and the Brief Patient Health Questionnaire measured depressive symptoms and probable depression, respectively. Multilevel growth models also considered demographics, psychosocial characteristics, and other drug use. Ecstasy use was not associated with long-term depressive symptoms or greater odds of depression in multivariate analyses. Users had more self-reported depressive symptoms when using ecstasy compared to not using. However, differences between people who had and had not ever used ecstasy largely accounted for this. Other factors were more important in the prediction of depression. It would be premature to conclude that ecstasy use is not related to the development of long-term depressive symptoms, given the relatively low level of ecstasy and other drug use in this community sample. Results showed that other factors need to be considered when investigating ecstasy use and depression.

  9. Testing cross-phenotype effects of rare variants in longitudinal studies of complex traits.

    PubMed

    Rudra, Pratyaydipta; Broadaway, K Alaine; Ware, Erin B; Jhun, Min A; Bielak, Lawrence F; Zhao, Wei; Smith, Jennifer A; Peyser, Patricia A; Kardia, Sharon L R; Epstein, Michael P; Ghosh, Debashis

    2018-06-01

    Many gene mapping studies of complex traits have identified genes or variants that influence multiple phenotypes. With the advent of next-generation sequencing technology, there has been substantial interest in identifying rare variants in genes that possess cross-phenotype effects. In the presence of such effects, modeling both the phenotypes and rare variants collectively using multivariate models can achieve higher statistical power compared to univariate methods that either model each phenotype separately or perform separate tests for each variant. Several studies collect phenotypic data over time and using such longitudinal data can further increase the power to detect genetic associations. Although rare-variant approaches exist for testing cross-phenotype effects at a single time point, there is no analogous method for performing such analyses using longitudinal outcomes. In order to fill this important gap, we propose an extension of Gene Association with Multiple Traits (GAMuT) test, a method for cross-phenotype analysis of rare variants using a framework based on the distance covariance. The approach allows for both binary and continuous phenotypes and can also adjust for covariates. Our simple adjustment to the GAMuT test allows it to handle longitudinal data and to gain power by exploiting temporal correlation. The approach is computationally efficient and applicable on a genome-wide scale due to the use of a closed-form test whose significance can be evaluated analytically. We use simulated data to demonstrate that our method has favorable power over competing approaches and also apply our approach to exome chip data from the Genetic Epidemiology Network of Arteriopathy. © 2018 WILEY PERIODICALS, INC.

  10. Investigation of 2-stage meta-analysis methods for joint longitudinal and time-to-event data through simulation and real data application.

    PubMed

    Sudell, Maria; Tudur Smith, Catrin; Gueyffier, François; Kolamunnage-Dona, Ruwanthi

    2018-04-15

    Joint modelling of longitudinal and time-to-event data is often preferred over separate longitudinal or time-to-event analyses as it can account for study dropout, error in longitudinally measured covariates, and correlation between longitudinal and time-to-event outcomes. The joint modelling literature focuses mainly on the analysis of single studies with no methods currently available for the meta-analysis of joint model estimates from multiple studies. We propose a 2-stage method for meta-analysis of joint model estimates. These methods are applied to the INDANA dataset to combine joint model estimates of systolic blood pressure with time to death, time to myocardial infarction, and time to stroke. Results are compared to meta-analyses of separate longitudinal or time-to-event models. A simulation study is conducted to contrast separate versus joint analyses over a range of scenarios. Using the real dataset, similar results were obtained by using the separate and joint analyses. However, the simulation study indicated a benefit of use of joint rather than separate methods in a meta-analytic setting where association exists between the longitudinal and time-to-event outcomes. Where evidence of association between longitudinal and time-to-event outcomes exists, results from joint models over standalone analyses should be pooled in 2-stage meta-analyses. © 2017 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

  11. Longitudinal and cross-sectional analyses of visual field progression in participants of the Ocular Hypertension Treatment Study.

    PubMed

    Artes, Paul H; Chauhan, Balwantray C; Keltner, John L; Cello, Kim E; Johnson, Chris A; Anderson, Douglas R; Gordon, Mae O; Kass, Michael A

    2010-12-01

    To assess agreement between longitudinal and cross-sectional analyses for determining visual field progression in data from the Ocular Hypertension Treatment Study. Visual field data from 3088 eyes of 1570 participants (median follow-up, 7 years) were analyzed. Longitudinal analyses were performed using change probability with total and pattern deviation, and cross-sectional analyses were performed using the glaucoma hemifield test, corrected pattern standard deviation, and mean deviation. The rates of mean deviation and general height change were compared to estimate the degree of diffuse loss in emerging glaucoma. Agreement on progression in longitudinal and cross-sectional analyses ranged from 50% to 61% and remained nearly constant across a wide range of criteria. In contrast, agreement on absence of progression ranged from 97.0% to 99.7%, being highest for the stricter criteria. Analyses of pattern deviation were more conservative than analyses of total deviation, with a 3 to 5 times lesser incidence of progression. Most participants developing field loss had both diffuse and focal changes. Despite considerable overall agreement, 40% to 50% of eyes identified as having progressed with either longitudinal or cross-sectional analyses were identified with only one of the analyses. Because diffuse change is part of early glaucomatous damage, pattern deviation analyses may underestimate progression in patients with ocular hypertension.

  12. Longitudinal Association between Periodontitis and Development of Diabetes Running title: Periodontitis and Diabetes Development.

    PubMed

    Joshipura, Kaumudi J; Muñoz-Torres, Francisco J; Dye, Bruce A; Leroux, Brian G; Ramírez-Vick, Margarita; Pérez, Cynthia M

    2018-04-18

    Clinical trials have shown very modest short-term improvements in glycemic control among participants with diabetes after periodontitis treatment. Few longitudinal studies suggest that periodontitis may be related to prediabetes/diabetes risk. We evaluated 1,206 diabetes free participants in the San Juan Overweight Adults Longitudinal Study (SOALS) and 941 with complete 3-year follow-up data were included. The National Health and Nutrition Examination Survey (NHANES) methods were used to assess periodontitis. Diabetes and prediabetes were classified using American Diabetes Association cutoffs for fasting and 2-hour post-load glucose and HbA1c. We used Poisson regression adjusting for baseline age, gender, smoking, education, family history of diabetes, physical activity, waist circumference, and alcohol intake. Over the 3-year follow-up, 69 (7.3%) of the 941 individuals developed type 2 diabetes, and 142 (34.9%) of the 407 with normal glycemia at baseline developed prediabetes. In multivariable models, greater mean pocket depth and mean attachment loss at baseline were associated with lower risk of developing prediabetes/diabetes over the follow-up (IRR=0.81; 95% CI: 0.67-0.99, and IRR=0.86; 95% CI: 0.74-0.99, respectively). Increase in periodontal attachment loss from baseline to follow-up was associated with higher prediabetes/diabetes risk (multivariate IRR=1.25; 95% CI: 1.09-1.42), and increase in pocket depth was associated with >20% fasting glucose increase (multivariate IRR=1.43; 95% CI: 1.14-1.79). The inverse associations persisted after additionally adjusting for baseline income, sugar-sweetened beverages, number of teeth, oral hygiene, glycemia, or previous periodontal therapy. There is no association between periodontitis and risk of prediabetes/diabetes in this longitudinal study. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Differences in Causal Estimates from Longitudinal Analyses of Residualized versus Simple Gain Scores: Contrasting Controls for Selection and Regression Artifacts

    ERIC Educational Resources Information Center

    Larzelere, Robert E.; Ferrer, Emilio; Kuhn, Brett R.; Danelia, Ketevan

    2010-01-01

    This study estimates the causal effects of six corrective actions for children's problem behaviors, comparing four types of longitudinal analyses that correct for pre-existing differences in a cohort of 1,464 4- and 5-year-olds from Canadian National Longitudinal Survey of Children and Youth (NLSCY) data. Analyses of residualized gain scores found…

  14. Exposure to Radiofrequency Electromagnetic Fields and Sleep Quality: A Prospective Cohort Study

    PubMed Central

    Mohler, Evelyn; Frei, Patrizia; Fröhlich, Jürg; Braun-Fahrländer, Charlotte; Röösli, Martin

    2012-01-01

    Background There is persistent public concern about sleep disturbances due to radiofrequency electromagnetic field (RF-EMF) exposure. The aim of this prospective cohort study was to investigate whether sleep quality is affected by mobile phone use or by other RF-EMF sources in the everyday environment. Methods We conducted a prospective cohort study with 955 study participants aged between 30 and 60 years. Sleep quality and daytime sleepiness was assessed by means of standardized questionnaires in May 2008 (baseline) and May 2009 (follow-up). We also asked about mobile and cordless phone use and asked study participants for consent to obtain their mobile phone connection data from the mobile phone operators. Exposure to environmental RF-EMF was computed for each study participant using a previously developed and validated prediction model. In a nested sample of 119 study participants, RF-EMF exposure was measured in the bedroom and data on sleep behavior was collected by means of actigraphy during two weeks. Data were analyzed using multivariable regression models adjusted for relevant confounders. Results In the longitudinal analyses neither operator-recorded nor self-reported mobile phone use was associated with sleep disturbances or daytime sleepiness. Also, exposure to environmental RF-EMF did not affect self-reported sleep quality. The results from the longitudinal analyses were confirmed in the nested sleep study with objectively recorded exposure and measured sleep behavior data. Conclusions We did not find evidence for adverse effects on sleep quality from RF-EMF exposure in our everyday environment. PMID:22624036

  15. Poverty and Child Development: A Longitudinal Study of the Impact of the Earned Income Tax Credit

    PubMed Central

    Hamad, Rita; Rehkopf, David H.

    2016-01-01

    Although adverse socioeconomic conditions are correlated with worse child health and development, the effects of poverty-alleviation policies are less understood. We examined the associations of the Earned Income Tax Credit (EITC) on child development and used an instrumental variable approach to estimate the potential impacts of income. We used data from the US National Longitudinal Survey of Youth (n = 8,186) during 1986–2000 to examine effects on the Behavioral Problems Index (BPI) and Home Observation Measurement of the Environment inventory (HOME) scores. We conducted 2 analyses. In the first, we used multivariate linear regressions with child-level fixed effects to examine the association of EITC payment size with BPI and HOME scores; in the second, we used EITC payment size as an instrument to estimate the associations of income with BPI and HOME scores. In linear regression models, higher EITC payments were associated with improved short-term BPI scores (per $1,000, β = −0.57; P = 0.04). In instrumental variable analyses, higher income was associated with improved short-term BPI scores (per $1,000, β = −0.47; P = 0.01) and medium-term HOME scores (per $1,000, β = 0.64; P = 0.02). Our results suggest that both EITC benefits and higher income are associated with modest but meaningful improvements in child development. These findings provide valuable information for health researchers and policymakers for improving child health and development. PMID:27056961

  16. Forgotten marriages? Measuring the reliability of marriage histories

    PubMed Central

    Chae, Sophia

    2016-01-01

    BACKGROUND Marriage histories are a valuable data source for investigating nuptiality. While researchers typically acknowledge the problems associated with their use, it is unknown to what extent these problems occur and how marriage analyses are affected. OBJECTIVE This paper seeks to investigate the quality of marriage histories by measuring levels of misreporting, examining the characteristics associated with misreporting, and assessing whether misreporting biases marriage indicators. METHODS Using data from the Malawi Longitudinal Study of Families and Health (MLSFH), I compare marriage histories reported by the same respondents at two different points in time. I investigate whether respondents consistently report their spouses (by name), status of marriage, and dates of marriage. I use multivariate regression models to investigate the characteristics associated with misreporting. Finally, I examine whether misreporting marriages and marriage dates affects marriage indicators. RESULTS Results indicate that 28.3% of men and 17.9% of women omitted at least one marriage in one of the survey waves. Multivariate regression models show that misreporting is not random: marriage, individual, interviewer, and survey characteristics are associated with marriage omission and marriage date inconsistencies. Misreporting also affects marriage indicators. CONCLUSIONS This is the first study of its kind to examine the reliability of marriage histories collected in the context of Sub-Saharan Africa. Although marriage histories are frequently used to study marriage dynamics, until now no knowledge has existed on the degree of misreporting. Misreporting in marriage histories is shown to be non-negligent and could potentially affect analyses. PMID:27152090

  17. Predictors of regular cigarette smoking among adolescent females: Does body image matter?

    PubMed Central

    Kaufman, Annette R.; Augustson, Erik M.

    2013-01-01

    This study examined how factors associated with body image predict regular smoking in adolescent females. Data were from the National Longitudinal Study of Adolescent Health (Add Health), a study of health-related behaviors in a nationally representative sample of adolescents in grades 7 through 12. Females in Waves I and II (n=6,956) were used for this study. Using SUDAAN to adjust for the sampling frame, univariate and multivariate analyses were performed to investigate if baseline body image factors, including perceived weight, perceived physical development, trying to lose weight, and self-esteem, were predictive of regular smoking status 1 year later. In univariate analyses, perceived weight (p<.01), perceived physical development (p<.0001), trying to lose weight (p<.05), and self-esteem (p<.0001) significantly predicted regular smoking 1 year later. In the logistic regression model, perceived physical development (p<.05), and self-esteem (p<.001) significantly predicted regular smoking. The more developed a female reported being in comparison to other females her age, the more likely she was to be a regular smoker. Lower self-esteem was predictive of regular smoking. Perceived weight and trying to lose weight failed to reach statistical significance in the multivariate model. This current study highlights the importance of perceived physical development and self-esteem when predicting regular smoking in adolescent females. Efforts to promote positive self-esteem in young females may be an important strategy when creating interventions to reduce regular cigarette smoking. PMID:18686177

  18. Central nervous system medication use and incident mobility limitation in community elders: the Health, Aging, and Body Composition study.

    PubMed

    Boudreau, Robert M; Hanlon, Joseph T; Roumani, Yazan F; Studenski, Stephanie A; Ruby, Christine M; Wright, Rollin M; Hilmer, Sarah N; Shorr, Ronald I; Bauer, Douglas C; Simonsick, Eleanor M; Newman, Anne B

    2009-10-01

    To evaluate whether CNS medication use in older adults was associated with a higher risk of future incident mobility limitation. This 5-year longitudinal cohort study included 3055 participants from the health, aging and body composition (Health ABC) study who were well-functioning at baseline. CNS medication use (benzodiazepine and opioid receptor agonists, antipsychotics, and antidepressants) was determined yearly (except year 4) during in-home or in-clinic interviews. Summated standardized daily doses (low, medium, and high) and duration of CNS drug use were computed. Incident mobility limitation was operationalized as two consecutive self-reports of having any difficulty walking 1/4 mile or climbing 10 steps without resting every 6 months after baseline. Multivariable Cox proportional hazard analyses were conducted adjusting for demographics, health behaviors, health status, and common indications for CNS medications. Each year at least 13.9% of participants used a CNS medication. By year 6, overall 49% had developed incident mobility limitation. In multivariable models, CNS medication users compared to never users showed a higher risk for incident mobility limitation (adjusted hazard ratio (Adj. HR) 1.28; 95% confidence interval (CI) 1.12-1.47). Similar findings of increased risk were seen in analyses examining dose- and duration-response relationships. CNS medication use is independently associated with an increased risk of future incident mobility limitation in community dwelling elderly. Further studies are needed to determine the impact of reducing CNS medication exposure on mobility problems. 2009 John Wiley & Sons, Ltd.

  19. The Effect of Injuries on Health Measured by Short Form 8 among a Large Cohort of Thai Adults

    PubMed Central

    Yiengprugsawan, Vasoontara; Berecki-Gisolf, Janneke; McClure, Roderick; Kelly, Matthew; Seubsman, Sam-ang; Sleigh, Adrian C.

    2014-01-01

    Introduction We investigate the links between health and injury in Thailand. This is important because of the high burden of injury in transitional countries and limited information for public health. Methods We analyse 2005 baseline and 2009, 4-year follow-up data from distance learning students of Sukhothai Thammathirat Open University residing nationwide (n = 60569). Injury was reported for the past year in both periods. Medical Outcome Study Short-Form (SF-8™) health status was reported and Physical and Mental Component Summary Scores (PCS and MCS) were calculated. Analyses used covariate-adjusted multivariate linear regression. Results In 2009, increasing numbers of traffic injuries (0, 1, 2, 3, 4+) associated with declining PCS scores (49.8, 48.4, 46.9, 46.2, 44.0), along with a similar monotonic decline for MCS scores (47.6, 46.0, 44.2, 42.7, 40.6). A similar (but smaller) dose-response gradient was found between non-traffic injuries and SF-8 scores. Longitudinal analyses showed those with incident injury (no injury 2005, injury 2009) had lower PCS and MCS scores compared to those with no injury in both periods. Individuals with reverting injury status (injury 2005, no injury 2009) reported improvement in PCS and MCS scores over the four-year period. Conclusion We found significant and epidemiologically important associations between increasing injury frequency and worse health in the past year, especially traffic injuries. Longitudinal 2005–2009 results were supportive and revealed statistically significant adverse 4-year effects of incident injury on health. If injury reverted over four years, low initial scores improved greatly. Findings highlight the importance of injury prevention as a public health priority. PMID:24551187

  20. Patient-reported safety incidents in older patients with long-term conditions: a large cross-sectional study

    PubMed Central

    Panagioti, Maria; Blakeman, Thomas; Hann, Mark; Bower, Peter

    2017-01-01

    Background Increasing evidence suggests that patient safety is a serious concern for older patients with long-term conditions. Despite this, there is a lack of research on safety incidents encountered by this patient group. In this study, we sought to examine patient reports of safety incidents and factors associated with reports of safety incidents in older patients with long-term conditions. Methods The baseline cross-sectional data from a longitudinal cohort study were analysed. Older patients (n=3378 aged 65 years and over) with a long-term condition registered in general practices were included in the study. The main outcome was patient-reported safety incidents including availability and appropriateness of medical tests and prescription of wrong types or doses of medication. Binary univariate and multivariate logistic regression analyses were undertaken to examine factors associated with patient-reported safety incidents. Results Safety incidents were reported by 11% of the patients. Four factors were significantly associated with patient-reported safety incidents in multivariate analyses. The experience of multiple long-term conditions (OR=1.09, 95% CI 1.05 to 1.13), a probable diagnosis of depression (OR=1.36, 95% CI 1.06 to 1.74) and greater relational continuity of care (OR=1.28, 95% CI 1.08 to 1.52) were associated with increased odds for patient-reported safety incidents. Perceived greater support and involvement in self-management was associated with lower odds for patient-reported safety incidents (OR=0.95, 95% CI 0.93 to 0.97). Conclusions We found that older patients with multimorbidity and depression are more likely to report experiences of patient safety incidents. Improving perceived support and involvement of patients in their care may help prevent patient-reported safety incidents. PMID:28559454

  1. The impact of increased body mass index on systemic lupus erythematosus: data from LUMINA, a multiethnic cohort (LUMINA XLVI) [corrected].

    PubMed

    Chaiamnuay, Sumapa; Bertoli, Ana M; Fernández, Mónica; Apte, Mandar; Vilá, Luis M; Reveille, John D; Alarcón, Graciela S

    2007-06-01

    The aim of this study was to examine the impact of an increased body mass index (BMI) on disease activity, damage accrual, fatigue, self-reported health-related quality of life (HRQOL), and fibromyalgia in patients with lupus using longitudinal data from LUMINA, a large multiethnic cohort. SLE patients (>/=4 ACR revised criteria), /=30 kg/m). An increased BMI was associated with older age, less social support, higher degree of helplessness, depression, more abnormal illness-related behaviors, poorer self-reported HRQOL, fatigue, and fibromyalgia, but not with disease activity or damage accrual by univariable analyses. In multivariable analyses, BMI was independently associated with fibromyalgia but not with disease activity, fatigue, or self-reported HRQOL. An increased BMI is independently associated with presence of fibromyalgia but not with disease activity, damage accrual, fatigue or self-reported quality of life in patients with SLE. Optimizing weight merits investigation to see if it can significantly impact this pervasive SLE-associated manifestation.

  2. Factors associated with syphilis treatment failure and reinfection: a longitudinal cohort study in Shenzhen, China.

    PubMed

    Luo, Zhenzhou; Zhu, Lin; Ding, Yi; Yuan, Jun; Li, Wu; Wu, Qiuhong; Tian, Lishan; Zhang, Li; Zhou, Guomao; Zhang, Tao; Ma, Jianping; Chen, Zhongwei; Yang, Tubao; Feng, Tiejian; Zhang, Min

    2017-09-13

    The treatment failure and reinfection rates among syphilis patients are high, and relevant studies in China are limited. The aim of this study was to detect the rates of treatment failure and reinfection after syphilis treatment and to explore the potential associated factors. We conducted a longitudinal cohort study in a sexually transmitted disease clinic, the Department of Dermatology and Venereology in Nanshan Center for Chronic Disease Control. Serological testing was performed at baseline and throughout the 2-year follow-up for syphilis patients. To identify potential predictors of treatment outcomes, multivariate logistics analyses were utilized to compare the demographic and clinical characteristics of patients with serological failure/reinfection to those with serological cure/serofast. From June 2011 to June 2016, a total of 1133 patients were screened for syphilis. Among the 770 patients who completed the 2-year follow-up, 510 first-diagnosed patients were included in the final analysis. Multivariate logistics analysis revealed the stage of syphilis (secondary syphilis VS. primary syphilis: adjusted odds ratio, 3.50; 95% confidence interval, 1.11-15.47; p = 0.04), HIV status (positive VS. negative: adjusted odds ratio, 3.06; 95% confidence interval, 1.15-8.04; p = 0.02) and frequency of condom use (always use VS. never use: adjusted odds ratio, 0.28; 95% confidence interval 0.08-0.75; p = 0.02) were significantly associated with the serological outcome. The clinical implications of our findings suggest that it is very important to perform regular clinical and serologic evaluations after treatment. Health counseling and safety education on sex activity should be intensified among HIV-infected patients and secondary syphilis patients after treatment.

  3. Correlates of amphetamine-type stimulants use and associations with HIV-related risks among young women engaged in sex work in Phnom Penh, Cambodia

    PubMed Central

    Couture, Marie-Claude; Evans, Jennifer L.; Sothy, Neth San; Stein, Ellen S.; Sichan, Keo; Maher, Lisa; Page, Kimberly

    2011-01-01

    Background Amphetamine-type stimulant (ATS) use has increased in Cambodia and emerged as a significant problem among female sex workers (FSWs), potentially contributing to increased risk of HIV. We examined the prevalence of ATS use and its effect on sexual risk behaviors, and sexually transmitted infections (STI) among FSWs in Phnom Penh, Cambodia. Methods A one-year prospective study among young women engaged in sex work in brothels, entertainment establishments and on a freelance basis. Socio-demographics, sexual risks, and recent ATS use were assessed by self-report. Blood and urine samples were collected to detect HIV, Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC). Bivariate and multivariate longitudinal analyses were conducted to assess the effects of ATS use on number of sex partners, inconsistent condom use with paying partners and incident STI. Results ATS use was higher among women working freelance (35.6%) and in brothels (34.8%) compared to women working in entertainment establishments (17.7%) or in multiple venues (14.8%). ATS users reported more sex partners and days drunk in the previous month. In multivariate longitudinal analysis, ATS use was associated with having a higher number of sex partners (Adjusted Risk Ratio 1.49; 95% CI: 1.00–2.21) and incident STI (Adjusted Odds Ratio 5.41; 95% CI: 1.15–25.48), but not inconsistent condom use with paying partner. Conclusion ATS users had more sex partners, high level of alcohol use, and were at increased risk of STI. Our findings underscore ATS use as an important emerging risk exposure that should be integrated into HIV prevention interventions targeting this population. PMID:21820251

  4. Parental mood during pregnancy and post-natally is associated with offspring risk of Tourette syndrome or chronic tics: prospective data from the Avon Longitudinal Study of Parents and Children (ALSPAC).

    PubMed

    Ben-Shlomo, Y; Scharf, J M; Miller, L L; Mathews, C A

    2016-04-01

    Little is known about risk factors for Tourette syndrome (TS) and chronic tic disorders (CT) but maternal psychological morbidity in pregnancy may be associated with TS/CT. We examined whether pre- and post-natal parental anxiety and/or depression are associated with risk of TS/CT in the Avon Longitudinal Study of Parents and Children. We compared self-reported anxiety and depression measures collected prospectively at four time points (18 and 32 weeks prenatally, and 8 weeks and 8 months post-natally) among parents of children who subsequently met criteria for TS/CT at 13 years of age as compared to other children from the cohort. We adjusted for various socioeconomic measures and tested both for time period-specific exposure and chronic exposure using multivariable logistic regression models. 122 children had TS/CT (50 TS, 72 CT) and 5968 children had no tics. In crude analyses, both pre- and post-natal maternal anxiety and depression, but only post-natal paternal depression at 8 months, showed associations with TS/CT. In the final, adjusted multivariable models, chronic maternal anxiety (odds ratio 2.17, 95% CI 1.23, 3.84, p = 0.007) and pre-natal maternal depression (odds ratio 1.86, 95% CI 1.02, 3.39, p = 0.04) showed associations with TS/CT though the latter was consistent with chance (p = 0.07) after adjustment for past maternal depression. We find associations between maternal psychological morbidity pre- and post-natally and risk of future TS/CT in offspring. These associations may reflect either shared genetic susceptibility or a pre-natal exposure. Further work is required to see if these findings can be replicated in larger datasets.

  5. Incident Subjective Cognitive Decline Does Not Predict Mortality in the Elderly--Results from the Longitudinal German Study on Ageing, Cognition, and Dementia (AgeCoDe).

    PubMed

    Roehr, Susanne; Luck, Tobias; Heser, Kathrin; Fuchs, Angela; Ernst, Annette; Wiese, Birgitt; Werle, Jochen; Bickel, Horst; Brettschneider, Christian; Koppara, Alexander; Pentzek, Michael; Lange, Carolin; Prokein, Jana; Weyerer, Siegfried; Mösch, Edelgard; König, Hans-Helmut; Maier, Wolfgang; Scherer, Martin; Jessen, Frank; Riedel-Heller, Steffi G

    2016-01-01

    Subjective cognitive decline (SCD) might represent the first symptomatic representation of Alzheimer's disease (AD), which is associated with increased mortality. Only few studies, however, have analyzed the association of SCD and mortality, and if so, based on prevalent cases. Thus, we investigated incident SCD in memory and mortality. Data were derived from the German AgeCoDe study, a prospective longitudinal study on the epidemiology of mild cognitive impairment (MCI) and dementia in primary care patients over 75 years covering an observation period of 7.5 years. We used univariate and multivariate Cox regression analyses to examine the relationship of SCD and mortality. Further, we estimated survival times by the Kaplan Meier method and case-fatality rates with regard to SCD. Among 971 individuals without objective cognitive impairment, 233 (24.0%) incidentally expressed SCD at follow-up I. Incident SCD was not significantly associated with increased mortality in the univariate (HR = 1.0, 95% confidence interval = 0.8-1.3, p = .90) as well as in the multivariate analysis (HR = 0.9, 95% confidence interval = 0.7-1.2, p = .40). The same applied for SCD in relation to concerns. Mean survival time with SCD was 8.0 years (SD = 0.1) after onset. Incident SCD in memory in individuals with unimpaired cognitive performance does not predict mortality. The main reason might be that SCD does not ultimately lead into future cognitive decline in any case. However, as prevalence studies suggest, subjectively perceived decline in non-memory cognitive domains might be associated with increased mortality. Future studies may address mortality in such other cognitive domains of SCD in incident cases.

  6. Eating patterns and energy and nutrient intakes of US women.

    PubMed

    Haines, P S; Hungerford, D W; Popkin, B M; Guilkey, D K

    1992-06-01

    A longitudinal multivariate analysis was used to determine whether differences in energy and nutrient intakes were present for women classified into different eating patterns. Ten multidimensional eating patterns were created based on the proportion of energy consumed at home and at seven away-from-home locations. Data were from 1,120 women aged 19 through 50 years who were surveyed up to six times over a 1-year period as part of the 1985 Continuing Survey of Food Intake by Individuals, US Department of Agriculture. Data from 5,993 days were analyzed. To examine differences in energy and nutrient intakes, longitudinal multivariate analyses were used to control for eating pattern and factors such as demographics, season, and day of week. Younger women in the Fast Food eating pattern consumed the greatest intakes of energy, total fat, saturated fat, cholesterol, and sodium. Well-educated, higher-income women in the Restaurant pattern consumed diets with the highest overall fat density. Nutrient densities for dietary fiber, calcium, vitamin C, and folacin were particularly low in away-from-home eating patterns. In contrast, moderately educated, middle-aged and middle-income women in the Home Mixed eating pattern (70% at home, 30% away from home) consumed the most healthful diets. We conclude that knowledge of demographics such as income and education is not enough to target dietary interventions. Rather, educational efforts must consider both demographics and the location of away-from-home eating. This will allow development of behavioral change strategies that consider food choices dictated by the eating environment as well as personal knowledge and attitude factors related to adoption of healthful food choices.

  7. Associations between sensory loss and social networks, participation, support, and loneliness: Analysis of the Canadian Longitudinal Study on Aging.

    PubMed

    Mick, Paul; Parfyonov, Maksim; Wittich, Walter; Phillips, Natalie; Kathleen Pichora-Fuller, M

    2018-01-01

    To determine if hearing loss, vision loss, and dual sensory loss were associated with social network diversity, social participation, availability of social support, and loneliness, respectively, in a population-based sample of older Canadians and to determine whether age or sex modified the associations. Cross-sectional population-based study. Canada. The sample included 21 241 participants in the Canadian Longitudinal Study on Aging tracking cohort. The sample was nationally representative of English- and French-speaking, non-institutionalized 45- to 89-year-old Canadians who did not live on First Nations reserves and who had normal cognition. Participants with missing data for any of the variables in the multivariable regression models were excluded from analysis. Hearing and vision loss were determined by self-report. Dual sensory loss was defined as reporting both hearing and vision loss. Univariate analyses were performed to assess cross-sectional associations between hearing, vision, and dual sensory loss, and social, demographic, and medical variables. Multivariable regression models were used to analyze cross-sectional associations between each type of sensory loss and social network diversity, social participation, availability of social support, and loneliness. Vision loss (in men) and dual sensory loss (in 65- to 85-year-olds) were independently associated with reduced social network diversity. Vision loss and dual sensory loss (in 65- to 85-year-olds) were each independently associated with reduced social participation. All forms of sensory loss were associated with both low availability of social support and loneliness. Sensory impairment is associated with reduced social function in older Canadians. Interventions and research that address the social needs of older individuals with sensory loss are needed. Copyright© the College of Family Physicians of Canada.

  8. A Two Year Longitudinal Outcome Study of Addicted Health Care Professionals: An Investigation of the Role of Personality Variables

    PubMed Central

    Angres, Daniel; Bologeorges, Stephanie; Chou, Jessica

    2013-01-01

    The co-morbidity of personality disorders (PDs) and other dysregulatory personality patterns with addiction have been well-established, although few studies have examined this interplay on long-term sobriety outcome. In addition, health care professionals suffering from addiction have both a significant public health impact and a unique set of treatment and recovery challenges. The aim of this study was to investigate if personality variables differentiated sobriety outcome in this population over a two year interval. A clinical sample of health care professionals participated in a substance abuse hospital treatment program individually tailored with respect to personality. Participants took the Temperament and Character Inventory and the Millon Clinical Multiaxial Inventory at intake, and were tracked two years post-discharge to determine sobriety status. Univariate analyses showed antisocial personality, female gender, and alcohol dependence were independent predictors of relapse, however a significant relationship between personality and substance use did not exist in multivariate analysis when controlling for demographic variables The lack of multivariate relationships demonstrates the heterogeneity in self-report measures of personality, which suggests the interplay of personality and addiction is complex and individualized. PMID:23531922

  9. Housing Instability Among Current and Former Welfare Recipients

    PubMed Central

    Phinney, Robin; Danziger, Sheldon; Pollack, Harold A.; Seefeldt, Kristin

    2007-01-01

    Objectives. We examined correlates of eviction and homelessness among current and former welfare recipients from 1997 to 2003 in an urban Michigan community. Methods. Longitudinal cohort data were drawn from the Women’s Employment Study, a representative panel study of mothers who were receiving cash welfare in February 1997. We used logistic regression analysis to identify risk factors for both eviction and homelessness over the survey period. Results. Twenty percent (95% confidence interval [CI]=16%, 23%) of respondents were evicted and 12% (95% CI=10%, 15%) experienced homelessness at least once between fall 1997 and fall 2003. Multivariate analyses indicated 2 consistent risk factors: having less than a high school education and having used illicit drugs other than marijuana. Mental and physical health problems were significantly associated with homelessness but not evictions. A multivariate screening algorithm achieved 75% sensitivity and 67% specificity in identifying individuals at risk for homelessness. A corresponding algorithm for eviction achieved 75% sensitivity and 50% specificity. Conclusions. The high prevalence of housing instability among our respondents suggests the need to better target housing assistance and other social services to current and former welfare recipients with identifiable personal problems. PMID:17267717

  10. Biological and Sociocultural Factors During the School Years Predicting Women's Lifetime Educational Attainment.

    PubMed

    Hendrick, C Emily; Cohen, Alison K; Deardorff, Julianna; Cance, Jessica D

    2016-03-01

    Lifetime educational attainment is an important predictor of health and well-being for women in the United States. In this study, we examine the roles of sociocultural factors in youth and an understudied biological life event, pubertal timing, in predicting women's lifetime educational attainment. Using data from the National Longitudinal Survey of Youth 1997 cohort (N = 3889), we conducted sequential multivariate linear regression analyses to investigate the influences of macro-level and family-level sociocultural contextual factors in youth (region of country, urbanicity, race/ethnicity, year of birth, household composition, mother's education, and mother's age at first birth) and early menarche, a marker of early pubertal development, on women's educational attainment after age 24. Pubertal timing and all sociocultural factors in youth, other than year of birth, predicted women's lifetime educational attainment in bivariate models. Family factors had the strongest associations. When family factors were added to multivariate models, geographic region in youth, and pubertal timing were no longer significant. Our findings provide additional evidence that family factors should be considered when developing comprehensive and inclusive interventions in childhood and adolescence to promote lifetime educational attainment among girls. © 2016, American School Health Association.

  11. Multivariable Techniques for High-Speed Research Flight Control Systems

    NASA Technical Reports Server (NTRS)

    Newman, Brett A.

    1999-01-01

    This report describes the activities and findings conducted under contract with NASA Langley Research Center. Subject matter is the investigation of suitable multivariable flight control design methodologies and solutions for large, flexible high-speed vehicles. Specifically, methodologies are to address the inner control loops used for stabilization and augmentation of a highly coupled airframe system possibly involving rigid-body motion, structural vibrations, unsteady aerodynamics, and actuator dynamics. Design and analysis techniques considered in this body of work are both conventional-based and contemporary-based, and the vehicle of interest is the High-Speed Civil Transport (HSCT). Major findings include: (1) control architectures based on aft tail only are not well suited for highly flexible, high-speed vehicles, (2) theoretical underpinnings of the Wykes structural mode control logic is based on several assumptions concerning vehicle dynamic characteristics, and if not satisfied, the control logic can break down leading to mode destabilization, (3) two-loop control architectures that utilize small forward vanes with the aft tail provide highly attractive and feasible solutions to the longitudinal axis control challenges, and (4) closed-loop simulation sizing analyses indicate the baseline vane model utilized in this report is most likely oversized for normal loading conditions.

  12. Impact of loneliness and depression on mortality: results from the Longitudinal Ageing Study Amsterdam.

    PubMed

    Holwerda, Tjalling J; van Tilburg, Theo G; Deeg, Dorly J H; Schutter, Natasja; Van, Rien; Dekker, Jack; Stek, Max L; Beekman, Aartjan T F; Schoevers, Robert A

    2016-08-01

    Loneliness is highly prevalent among older people, has serious health consequences and is an important predictor of mortality. Loneliness and depression may unfavourably interact with each other over time but data on this topic are scarce. To determine whether loneliness is associated with excess mortality after 19 years of follow-up and whether the joint effect with depression confers further excess mortality. Different aspects of loneliness were measured with the De Jong Gierveld scale and depression with the Centre for Epidemiologic Studies Depression Scale in a cohort of 2878 people aged 55-85 with 19 years of follow-up. Excess mortality hypotheses were tested with Kaplan-Meier and Cox proportional hazard analyses controlling for potential confounders. At follow-up loneliness and depression were associated with excess mortality in older men and women in bivariate analysis but not in multivariate analysis. In multivariate analysis, severe depression was associated with excess mortality in men who were lonely but not in women. Loneliness and depression are important predictors of early death in older adults. Severe depression has a strong association with excess mortality in older men who were lonely, indicating a lethal combination in this group. © The Royal College of Psychiatrists 2016.

  13. Depression and poverty among African American women at risk for type 2 diabetes.

    PubMed

    de Groot, Mary; Auslander, Wendy; Williams, James Herbert; Sherraden, Michael; Haire-Joshu, Debra

    2003-01-01

    Poverty is associated with negative health outcomes, including depression. Little is known about the specific elements of poverty that contribute to depression, particularly among African American women at risk for type 2 diabetes. This study examined the relationships of economic and social resources to depression among African American women at high risk for the development of type 2 diabetes (N = 181) using the Conservation of Resources theory as a conceptual framework. Women were assessed at 3 time points in conjunction with a dietary change intervention. At baseline, 40% of women reported clinically significant depression, and 43.3% were below the poverty line. Depressed women reported fewer economic assets and greater economic distress than nondepressed peers. Multivariate logistic regression analyses indicated that nonwork status, lack of home ownership, low appraisal of one's economic situation, low self-esteem, and increased life events were significantly associated with depression at baseline. Longitudinal multivariate logistic regression models indicated that income, home ownership, future economic appraisal, life events, and self-esteem predicted depression trajectories at Time 3. These results speak to the multifaceted sources of stress in the lives of poor African American women. Interventions that address the economic and social factors associated with depression are needed.

  14. A model for incomplete longitudinal multivariate ordinal data.

    PubMed

    Liu, Li C

    2008-12-30

    In studies where multiple outcome items are repeatedly measured over time, missing data often occur. A longitudinal item response theory model is proposed for analysis of multivariate ordinal outcomes that are repeatedly measured. Under the MAR assumption, this model accommodates missing data at any level (missing item at any time point and/or missing time point). It allows for multiple random subject effects and the estimation of item discrimination parameters for the multiple outcome items. The covariates in the model can be at any level. Assuming either a probit or logistic response function, maximum marginal likelihood estimation is described utilizing multidimensional Gauss-Hermite quadrature for integration of the random effects. An iterative Fisher-scoring solution, which provides standard errors for all model parameters, is used. A data set from a longitudinal prevention study is used to motivate the application of the proposed model. In this study, multiple ordinal items of health behavior are repeatedly measured over time. Because of a planned missing design, subjects answered only two-third of all items at a given point. Copyright 2008 John Wiley & Sons, Ltd.

  15. Factors predicting health services use among older people in China: An analysis of the China Health and Retirement Longitudinal Study 2013.

    PubMed

    Gong, Cathy Honge; Kendig, Hal; He, Xiaojun

    2016-02-18

    Rapid population ageing in China is increasing the numbers of older people who are likely to require health services in response to higher levels of poor perceived health and chronic diseases. Understanding factors influencing health services use at late life will help to plan for increasing needs for health care, reducing inequalities in health services use and releasing severe pressures on a highly variable health care system that has constrained public resources and increasing reliance on health insurance and user payments. Drawing on the nationally representative China Health and Retirement Longitudinal Study 2013 data, we apply the Andersen healthcare utilization conceptual model to binary logistic regression multivariate analyses to examine the joint predictors of physical examinations, outpatient and inpatient care among the middle-aged and elderly in China. The multivariate analyses find that both physical examinations and inpatient care rates increase significantly by age when health deteriorates. Females are less likely to use inpatient care. Significant socio-economic variations exist in healthcare utilization. Older people with higher education, communist party membership, urban residence, non-agricultural household registration, better financial situation are more likely to have physical examinations or inpatient care. Factors influencing all three types of health care utilization are household expenditure, losing a partner, having multiple chronic diseases or perceiving poor health. With activities of daily living limitations or pain increases the probability of seeing a doctor while with functional loss increases the rates of having physical examinations, but being the ethnic minorities, no social health insurance, with depression, fair or poor memory could be a barrier to having physical examinations or seeing a doctor, which might delay the early diagnose of severe health problems among these groups. Not drinking, not smoking and regular physical exercises are adaptations after having health problems. As a rapidly ageing society, in order to address the increasing needs and inequalities in health care utilization, China is facing a massive challenge to reform the current health care system, improve equitable access to health insurance and financial affordability for the most disadvantaged, as well as to provide more health education and information to the general public.

  16. Inconsistent self-reported mammography history: Findings from the National Population Health Survey longitudinal cohort

    PubMed Central

    Bancej, Christina M; Maxwell, Colleen J; Snider, Judy

    2004-01-01

    Background Self-reported information has commonly been used to monitor mammography utilization across populations and time periods. However, longitudinal investigations regarding the prevalence and determinants of inconsistent responses over time and the impact of such responses on population screening estimates are lacking. Methods Based on longitudinal panel data for a representative cohort of Canadian women aged 40+ years (n = 3,537) assessed in the 1994–95 (baseline) and 1996–97 (follow-up) National Population Health Survey (NPHS), we examined the prevalence of inconsistent self-reports of mammography utilization. Logistic regression models were used to estimate the associations between women's baseline sociodemographic and health characteristics and 2 types of inconsistent responses: (i) baseline reports of ever use which were subsequently contradicted by follow-up reports of never use; and (ii) baseline reports of never use which were contradicted by follow-up reports of use prior to 1994–95. Results Among women who reported having a mammogram at baseline, 5.9% (95% confidence interval (CI): 4.6–7.3%) reported at follow-up that they had never had one. Multivariate logistic regression analyses showed that women with such inconsistent responses were more often outside target age groups, from low income households and less likely to report hormone replacement therapy and Pap smear use. Among women reporting never use at baseline and ever use at follow-up, 17.4% (95%CI: 11.7–23.1%) reported their most recent mammogram as occurring prior to 1994–95 (baseline) and such responses were more common among women aged 70+ years and those in poorer health. Conclusions Women with inconsistent responses of type (i), i.e., ever users at baseline but never users at follow-up, appeared to exhibit characteristics typical of never users of mammography screening. Although limited by sample size, our preliminary analyses suggest that type (ii) responses are more likely to be the result of recall bias due to competing morbidity and age. Inconsistent responses, if removed from the analyses, may be a greater source of loss to follow-up than deaths/institutionalization or item non-response. PMID:15541176

  17. Low HDL cholesterol as a cardiovascular risk factor in rural, urban, and rural-urban migrants: PERU MIGRANT cohort study

    PubMed Central

    Lazo-Porras, María; Bernabe-Ortiz, Antonio; Málaga, Germán; Gilman, Robert H.; Acuña-Villaorduña, Ana; Cardenas-Montero, Deborah; Smeeth, Liam; Miranda, J. Jaime

    2016-01-01

    Introduction Whilst the relationship between lipids and cardiovascular mortality has been well studied and appears to be controversial, very little has been explored in the context of rural-to-urban migration in low-resource settings. Objective Determine the profile and related factors for HDL-c patterns (isolated and non-isolated low HDL-c) in three population-based groups according to their migration status, and determine the effect of HDL-c patterns on the rates of cardiovascular outcomes (i.e. non-fatal stroke and non-fatal myocardial infarction) and mortality. Methods Cross-sectional and 5-year longitudinal data from the PERU MIGRANT study, designed to assess the effect of migration on cardiovascular risk profiles and mortality in Peru. Two different analyses were performed: first, we estimated prevalence and associated factors with isolated and non-isolated low HDL-c at baseline. Second, using longitudinal information, relative risk ratios (RRR) of composite outcomes of mortality, non-fatal stroke and non-fatal myocardial infarction were calculated according to HDL-c levels at baseline. Results Data from 988 participants, rural (n = 201), rural-to-urban migrants (n = 589), and urban (n = 199) groups, was analysed. Low HDL-c was present in 56.5% (95%CI: 53.4%–59.6%) without differences by study groups. Isolated low HDL-c was found in 36.5% (95%CI: 33.5–39.5%), with differences between study groups. In multivariable analysis, urban group (vs. rural), female gender, overweight and obesity were independently associated with isolated low HDL-c. Only female gender, overweight and obesity were associated with non-isolated low HDL-c. Longitudinal analyses showed that non-isolated low HDL-c increased the risk of negative cardiovascular outcomes (RRR = 3.46; 95%CI: 1.23–9.74). Conclusions Isolated low HDL-c was the most common dyslipidaemia in the study population and was more frequent in rural subjects. Non-isolated low HDL-c increased three-to fourfold the 5-year risk of cardiovascular outcomes. PMID:26752691

  18. Low HDL cholesterol as a cardiovascular risk factor in rural, urban, and rural-urban migrants: PERU MIGRANT cohort study.

    PubMed

    Lazo-Porras, María; Bernabe-Ortiz, Antonio; Málaga, Germán; Gilman, Robert H; Acuña-Villaorduña, Ana; Cardenas-Montero, Deborah; Smeeth, Liam; Miranda, J Jaime

    2016-03-01

    Whilst the relationship between lipids and cardiovascular mortality has been well studied and appears to be controversial, very little has been explored in the context of rural-to-urban migration in low-resource settings. Determine the profile and related factors for HDL-c patterns (isolated and non-isolated low HDL-c) in three population-based groups according to their migration status, and determine the effect of HDL-c patterns on the rates of cardiovascular outcomes (i.e. non-fatal stroke and non-fatal myocardial infarction) and mortality. Cross-sectional and 5-year longitudinal data from the PERU MIGRANT study, designed to assess the effect of migration on cardiovascular risk profiles and mortality in Peru. Two different analyses were performed: first, we estimated prevalence and associated factors with isolated and non-isolated low HDL-c at baseline. Second, using longitudinal information, relative risk ratios (RRR) of composite outcomes of mortality, non-fatal stroke and non-fatal myocardial infarction were calculated according to HDL-c levels at baseline. Data from 988 participants, rural (n = 201), rural-to-urban migrants (n = 589), and urban (n = 199) groups, was analysed. Low HDL-c was present in 56.5% (95%CI: 53.4%-59.6%) without differences by study groups. Isolated low HDL-c was found in 36.5% (95%CI: 33.5-39.5%), with differences between study groups. In multivariable analysis, urban group (vs. rural), female gender, overweight and obesity were independently associated with isolated low HDL-c. Only female gender, overweight and obesity were associated with non-isolated low HDL-c. Longitudinal analyses showed that non-isolated low HDL-c increased the risk of negative cardiovascular outcomes (RRR = 3.46; 95%CI: 1.23-9.74). Isolated low HDL-c was the most common dyslipidaemia in the study population and was more frequent in rural subjects. Non-isolated low HDL-c increased three-to fourfold the 5-year risk of cardiovascular outcomes. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  19. Genetic parameters for growth characteristics of free-range chickens under univariate random regression models.

    PubMed

    Rovadoscki, Gregori A; Petrini, Juliana; Ramirez-Diaz, Johanna; Pertile, Simone F N; Pertille, Fábio; Salvian, Mayara; Iung, Laiza H S; Rodriguez, Mary Ana P; Zampar, Aline; Gaya, Leila G; Carvalho, Rachel S B; Coelho, Antonio A D; Savino, Vicente J M; Coutinho, Luiz L; Mourão, Gerson B

    2016-09-01

    Repeated measures from the same individual have been analyzed by using repeatability and finite dimension models under univariate or multivariate analyses. However, in the last decade, the use of random regression models for genetic studies with longitudinal data have become more common. Thus, the aim of this research was to estimate genetic parameters for body weight of four experimental chicken lines by using univariate random regression models. Body weight data from hatching to 84 days of age (n = 34,730) from four experimental free-range chicken lines (7P, Caipirão da ESALQ, Caipirinha da ESALQ and Carijó Barbado) were used. The analysis model included the fixed effects of contemporary group (gender and rearing system), fixed regression coefficients for age at measurement, and random regression coefficients for permanent environmental effects and additive genetic effects. Heterogeneous variances for residual effects were considered, and one residual variance was assigned for each of six subclasses of age at measurement. Random regression curves were modeled by using Legendre polynomials of the second and third orders, with the best model chosen based on the Akaike Information Criterion, Bayesian Information Criterion, and restricted maximum likelihood. Multivariate analyses under the same animal mixed model were also performed for the validation of the random regression models. The Legendre polynomials of second order were better for describing the growth curves of the lines studied. Moderate to high heritabilities (h(2) = 0.15 to 0.98) were estimated for body weight between one and 84 days of age, suggesting that selection for body weight at all ages can be used as a selection criteria. Genetic correlations among body weight records obtained through multivariate analyses ranged from 0.18 to 0.96, 0.12 to 0.89, 0.06 to 0.96, and 0.28 to 0.96 in 7P, Caipirão da ESALQ, Caipirinha da ESALQ, and Carijó Barbado chicken lines, respectively. Results indicate that genetic gain for body weight can be achieved by selection. Also, selection for body weight at 42 days of age can be maintained as a selection criterion. © 2016 Poultry Science Association Inc.

  20. Risk factors associated with white spot syndrome virus infection in a Vietnamese rice-shrimp farming system.

    PubMed

    Corsin, F; Turnbull, J F; Hao, N V; Mohan, C V; Phi, T T; Phuoc, L H; Tinh, N T; Morgan, K L

    2001-10-29

    White spot disease (WSD) is a pandemic disease caused by a virus commonly known as white spot syndrome virus (WSSV). Several risk factors for WSD outbreaks have been suggested. However, there have been very few studies to identify risk factors for WSD outbreaks in culture systems. This paper presents and discusses the risk factors for WSSV infection identified during a longitudinal observational study conducted in a Vietnamese rice-shrimp farming system. A total of 158 variables were measured comprising location, features of the pond, management practices, pond bottom quality, shrimp health and other animals in the pond. At the end of the study period WSSV was detected in 15 of the 24 ponds followed through the production cycle (62.5%). One hundred and thirty-nine variables were used in univariate analyses. All the variables with a p-value < or = 0.10 were used in unconditional logistic regression in a forward stepwise model. An effect of location was identified in both univariate and multivariate analyses showing that ponds located in the eastern portion of the study site, closer to the sea, were more likely to test positive for WSSV by 1-step PCR at harvest. Ponds with shrimp of a smaller average size 1 mo after stocking tended to be positive for WSSV at the end of the production cycle. Average weight at 1 mo was also highlighted in multivariate analyses when considered as either a risk factor or an outcome. Other risk factors identified in univariate analyses were earlier date of stocking and use of commercial feed. A number of variables also appeared to be associated with a reduced risk of WSSV at harvest including the presence of dead post larvae in the batch sampled at stocking, presence of Hemigrapsus spp. crabs during the first month of production, feeding vitamin premix or legumes, presence of high numbers of shrimp with bacterial infection and the presence of larger mud crabs or gobies at harvest. No associations were detected with WSSV at harvest and stocking density, presence, or number or weight of wild shrimp in the pond. The multivariate model to identify outcomes associated with WSSV infection highlighted the presence of high mortality as the main variable explaining the data. The results obtained from this study are discussed in the context of WSD control and areas requiring further investigation are suggested.

  1. Specifying the Role of Exposure to Violence and Violent Behavior on Initiation of Gun Carrying: A Longitudinal Test of Three Models of Youth Gun Carrying

    ERIC Educational Resources Information Center

    Spano, Richard; Pridemore, William Alex; Bolland, John

    2012-01-01

    Two waves of longitudinal data from 1,049 African American youth living in extreme poverty are used to examine the impact of exposure to violence (Time 1) and violent behavior (Time 1) on first time gun carrying (Time 2). Multivariate logistic regression results indicate that (a) violent behavior (Time 1) increased the likelihood of initiation of…

  2. Gender differences in the effects of exposure to intimate partner violence on adolescent violence and drug use.

    PubMed

    Fagan, Abigail A; Wright, Emily M

    2011-07-01

    This study investigated the long-term effects of exposure to intimate partner violence in the home on adolescent violence and drug use and gender differences in these relationships. Although the general relationship between exposure to IPV and negative outcomes for youth has been demonstrated in past research, gender differences in the effects of IPV on adolescents have been rarely assessed using longitudinal data. Longitudinal data was obtained from 1,315 adolescents and their primary caregivers participating in the Project on Human Development in Chicago Neighborhoods (PHDCN). The sample was 51% female and ethnically diverse (45% Hispanic, 37% African-American, and 14% Caucasian). Two waves of data were assessed to examine the effects of exposure to IPV, reported by caregivers when their children were aged 12 and 15, on violence and drug use, reported by adolescents 3 years later. Multivariate statistical models were employed to control for a range of child, parent, family, and neighborhood risk factors. Exposure to IPV did not significantly predict subsequent violence among males or females in multivariate analyses. IPV exposure was significantly related to the frequency of drug use for females but did not predict drug use among males. This gender difference was not statistically significant, however, which suggests more similarities than differences in the relationship between exposure to IPV and subsequent violence and drug use. This study supports prior research indicating that exposure to IPV can negatively impact adolescent development, but it suggests that these effects may be more likely to influence some outcomes (e.g., drug use) than others (e.g., interpersonal violence). The findings also emphasize the need for additional research examining the overall impact of IPV on adolescent problem behaviors and gender differences in these relationships, including longitudinal studies and investigations that control for a range of other important predictors. A better understanding of these relationships can help inform intervention efforts aimed at ensuring that adolescents living in violent households receive timely and appropriate services to help prevent the occurrence of future problem behaviors. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Rapid virological response of telaprevir and boceprevir in a Brazilian cohort of HCV genotype 1 patients: a multicenter longitudinal study.

    PubMed

    Borba, Helena Hl; Wiens, Astrid; Steimbach, Laiza M; Tonin, Fernanda S; Pedroso, Maria LA; Ivantes, Cláudia Ap; Fernandez-Llimos, Fernando; Pontarolo, Roberto

    2017-01-01

    Chronic hepatitis C is a major public health issue, but there is a gap in the literature regarding the effectiveness and safety of direct-acting antiviral agents in the Brazilian population. The main aim of this study was to describe the effectiveness of boceprevir and telaprevir in patients treated at public health care institutions in Brazil. A prospective longitudinal and multicenter study was conducted in five centers in the State of Paraná between September 2014 and June 2016. Data regarding effectiveness and safety were collected from medical records of patients treated with boceprevir or telaprevir. The effectiveness outcome comprised the rapid virological response (RVR). Multivariate analysis was performed to verify the influence of independent variables (ie, age, gender, baseline viral load) on RVR achievement. Data were collected from 117 patients with chronic hepatitis C virus (HCV) genotype 1 infection. Fifteen patients received treatment with boceprevir and 102 received telaprevir. The mean age was 51.6 years, 64.1% were male, 44.4% were infected with HCV subtype 1a, 62.4% had a high baseline viral load (≥800,000 IU/mL) and 33% were cirrhotic. Furthermore, 79.5% of patients achieved RVR (26.7% in the boceprevir group and 87.3% in the telaprevir group). Multivariate analysis demonstrated that the type of protease inhibitor (boceprevir or telaprevir) and the baseline viral load had an influence on the RVR rate (odds ratio [OR] =0.011; 95% confidence interval [CI]: 0.001-0.119; P <0.001/OR =13.004; 95% CI: 1.522-111.115; P =0.019, respectively). In this longitudinal multicenter cohort study conducted from the Brazilian perspective, differences were found in the RVR rates, favoring telaprevir over boceprevir for genotype 1 HCV-infected patients. In addition, the baseline viral load was associated with RVR achievement in both evaluated groups. As RVR is also reported in the literature as a predictor of the sustained virological response (SVR), further analyses of RVR as predictor of SVR outcomes should be further evaluated in Brazil.

  4. Longitudinal evaluation of milk type consumed and weight status in preschoolers.

    PubMed

    Scharf, Rebecca J; Demmer, Ryan T; DeBoer, Mark D

    2013-05-01

    To evaluate relationships between type of milk consumed and weight status among preschool children. Longitudinal cohort study. The Early Childhood Longitudinal Study, Birth Cohort, a representative sample of US children. 10 700 US children examined at age 2 and 4 years. Body mass index (BMI) z score and overweight/obese status as a function of milk type intake. The majority of children drank whole or 2% milk (87% at 2 years, 79.3% at 4 years). Across racial/ethnic and socio-economic status subgroups, 1%/skim milk drinkers had higher BMI z scores than 2%/whole milk drinkers. In multivariable analyses, increasing fat content in the type of milk consumed was inversely associated with BMI z score (p<0.0001). Compared to those drinking 2%/whole milk, 2- and 4-year-old children drinking 1%/skim milk had an increased adjusted odds of being overweight (age 2 OR 1.64, p<0.0001; age 4 OR 1.63, p<0.0001) or obese (age 2 OR 1.57, p<0.01; age 4 OR 1.64, p<0.0001). In longitudinal analysis, children drinking 1%/skim milk at both 2 and 4 years were more likely to become overweight/obese between these time points (adjusted OR 1.57, p<0.05). Consumption of 1%/skim milk is more common among overweight/obese preschoolers, potentially reflecting the choice of parents to give overweight/obese children low-fat milk to drink. Nevertheless, 1%/skim milk does not appear to restrain body weight gain between 2 and 4 years of age in this age range, emphasising a need for weight-targeted recommendations with a stronger evidence base.

  5. The Association of Health and Employment in Mature Women: A Longitudinal Study

    PubMed Central

    Byles, Julie

    2012-01-01

    Abstract Background Despite a reduction in income inequalities between men and women, there is still a large gap between income and retirement savings of Australian men and women. This is especially true for women who have health or disability problems. Mature age women are closest to retirement and, therefore, have less chance than younger women to build up enough retirement savings and may need to continue working to fund their older age. Continued workforce participation may be particularly difficult for women who are less healthy. Understanding which health problems lead to a decrease in workforce participation among mature age women is crucial. Therefore, this longitudinal study sought to identify which health problems are associated with employment among midage women over time. Methods Data were analyzed from the midage cohort of the Australian Longitudinal Study on Women's Health (ALSWH), which involved 14,200 midage women (aged 45–50 years in 1996). The women have been surveyed four additional times, in 1998, 2001, 2004, and 2007. Generalized estimating equations (GEE) were used to conduct nested multivariate longitudinal analyses. Results The percentages of women who were employed in the years 2001, 2004, and 2007 were 77%, 72%, and 68%, respectively. Results were adjusted for sociodemographic variables. Being employed decreased as physical and mental health deteriorated and with self-reported conditions: diabetes, high blood pressure, depression, anxiety, and other psychiatric conditions. Back pain, arthritis, cancer, obesity, and being a current smoker are associated with employment but not when quality of life is added to the model. Conclusions There were significant associations between health and employment. Understanding these relationships could inform policies and guidelines for preventing declines in employment in mature age women. PMID:22060315

  6. Drug Use Patterns and Continuous Enrollment in College:Results From a Longitudinal Study

    PubMed Central

    Arria, Amelia M.; Garnier-Dykstra, Laura M.; Caldeira, Kimberly M.; Vincent, Kathryn B.; Winick, Emily R.; O’Grady, Kevin E.

    2013-01-01

    Objective: Few longitudinal studies have examined the relationship between illicit drug use and academic outcomes among college students. This study characterized drug use patterns of a cohort of young adults who were originally enrolled as first-time, first-year college students in a longitudinal study. It evaluated the association between these drug use patterns and continuous enrollment during college, holding constant demographic characteristics, high school grade point average, fraternity/sorority involvement, personality/temperament characteristics, nicotine dependence, and alcohol use disorder. Method: Participants (n = 1,133; 47% male) were purposively selected from one university and interviewed annually for 4 years, beginning with their first year of college, regardless of continued college attendance. Enrollment data were culled from administrative records. Group-based trajectory analyses characterized 4-year longitudinal drug use patterns. Two grouping variables were derived based on (a) marijuana use frequency and (b) number of illicit drugs used other than marijuana. Seventy-one percent of the sample was continuously enrolled in the home institution during the first 4 years of study. Results: Multivariable logistic regression models demonstrated that infrequent, increasing, and chronic/heavy marijuana use patterns were significantly associated with discontinuous enrollment (adjusted odds ratio = 1.66, 1.74, and 1.99, respectively), compared with minimal use, holding constant covariates. In separate models, drug use other than marijuana also was significantly associated with discontinuous enrollment. Conclusions: Marijuana use and other illicit drug use are both associated with a decreased likelihood of continuous enrollment in college, independent of several other possible risk factors. These findings highlight the need for early intervention with illicit drug users to mitigate possible negative academic consequences. PMID:23200152

  7. Estimators for longitudinal latent exposure models: examining measurement model assumptions.

    PubMed

    Sánchez, Brisa N; Kim, Sehee; Sammel, Mary D

    2017-06-15

    Latent variable (LV) models are increasingly being used in environmental epidemiology as a way to summarize multiple environmental exposures and thus minimize statistical concerns that arise in multiple regression. LV models may be especially useful when multivariate exposures are collected repeatedly over time. LV models can accommodate a variety of assumptions but, at the same time, present the user with many choices for model specification particularly in the case of exposure data collected repeatedly over time. For instance, the user could assume conditional independence of observed exposure biomarkers given the latent exposure and, in the case of longitudinal latent exposure variables, time invariance of the measurement model. Choosing which assumptions to relax is not always straightforward. We were motivated by a study of prenatal lead exposure and mental development, where assumptions of the measurement model for the time-changing longitudinal exposure have appreciable impact on (maximum-likelihood) inferences about the health effects of lead exposure. Although we were not particularly interested in characterizing the change of the LV itself, imposing a longitudinal LV structure on the repeated multivariate exposure measures could result in high efficiency gains for the exposure-disease association. We examine the biases of maximum likelihood estimators when assumptions about the measurement model for the longitudinal latent exposure variable are violated. We adapt existing instrumental variable estimators to the case of longitudinal exposures and propose them as an alternative to estimate the health effects of a time-changing latent predictor. We show that instrumental variable estimators remain unbiased for a wide range of data generating models and have advantages in terms of mean squared error. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Novel Longitudinal and Propensity Score Matched Analysis of Hands-On Cooking and Nutrition Education versus Traditional Clinical Education among 627 Medical Students

    PubMed Central

    Monlezun, Dominique J.; Leong, Benjamin; Joo, Esther; Birkhead, Andrew G.; Sarris, Leah; Harlan, Timothy S.

    2015-01-01

    Background. Physicians are inadequately equipped to respond to the global obesity and nutrition-associated chronic disease epidemics. We investigated superiority of simulation-based medical education with deliberate practice (SBME-DP) hands-on cooking and nutrition elective in a medical school-based teaching kitchen versus traditional clinical education for medical students. Materials and Methods. A 59-question panel survey was distributed to an entire medical school twice annually from September 2012 to May 2014. Student diet and attitudes and competencies (DACs) counseling patients on nutrition were compared using conditional multivariate logistic regression, propensity score-weighted, and longitudinal panel analyses. Inverse-variance weighted meta-analysis (IVWM) was used for planned subgroup analysis by year and treatment estimates across the three methods. Results. Of the available 954 students, 65.72% (n = 627) unique students were followed to produce 963 responses. 11.32% (n = 109) of responses were from 84 subjects who participated in the elective. SBME-DP versus traditional education significantly improved fruit and vegetable diet (OR = 1.38, 95% CI: 1.07–1.79, p = 0.013) and attitudes (OR = 1.81, 95% CI: 1.40–2.35, p < 0.001) and competencies (OR = 1.72, 95% CI: 1.54–1.92, p < 0.001). Conclusions. This study reports for the first time superiority longitudinally for SBME-DP style nutrition education for medical students which has since expanded to 13 schools. PMID:26435851

  9. Dangerous dads? Ecological and longitudinal analyses of paternity leave and risk for child injury.

    PubMed

    Laflamme, Lucie; Månsdotter, Anna; Lundberg, Michael; Magnusson, Cecilia

    2012-11-01

    In 1974, Sweden became the first country to permit fathers to take paid parental leave. Other countries are currently following suit issuing similar laws. While this reform supports the principles of the United Nations convention of the right for children to be with both parents and enshrines the ethos of gender equality, there has been little systematic examination of its potential impact on child health. Instead, there is uninformed debate that fathers may expose their children to greater risks of injury than mothers. In this Swedish national study, the authors therefore assess whether fathers' parental leave can be regarded as a more serious risk factor for child injuries than that of mothers. Nationwide register-based ecological and longitudinal studies of hospitalisation due to injury (and intoxication) in early childhood, involving the Swedish population in 1973-2009 (ecological design), and children born in 1988 and 1989 (n=118 278) (longitudinal design). An increase in fathers' share of parental leave over time was parallelled by a downward trend in child injury rates (age 0-4 years). At the individual level, the crude incidence of child injury (age 0-2 years) was lower during paternity as compared with maternity leave. This association was, however, explained by parental socio-demographic characteristics (multivariate HR 0.96, 95% CI 0.74 to 1.2). There is no support for the notion that paternity leave increases the risk of child injury.

  10. Peripheral vascular damage in systemic lupus erythematosus: data from LUMINA, a large multi-ethnic U.S. cohort (LXIX).

    PubMed

    Burgos, P I; Vilá, L M; Reveille, J D; Alarcón, G S

    2009-12-01

    To determine the factors associated with peripheral vascular damage in systemic lupus erythematosus patients and its impact on survival from Lupus in Minorities, Nature versus Nurture, a longitudinal US multi-ethnic cohort. Peripheral vascular damage was defined by the Systemic Lupus International Collaborating Clinics Damage Index (SDI). Factors associated with peripheral vascular damage were examined by univariable and multi-variable logistic regression models and its impact on survival by a Cox multi-variable regression. Thirty-four (5.3%) of 637 patients (90% women, mean [SD] age 36.5 [12.6] [16-87] years) developed peripheral vascular damage. Age and the SDI (without peripheral vascular damage) were statistically significant (odds ratio [OR] = 1.05, 95% confidence interval [CI] 1.01-1.08; P = 0.0107 and OR = 1.30, 95% CI 0.09-1.56; P = 0.0043, respectively) in multi-variable analyses. Azathioprine, warfarin and statins were also statistically significant, and glucocorticoid use was borderline statistically significant (OR = 1.03, 95% CI 0.10-1.06; P = 0.0975). In the survival analysis, peripheral vascular damage was independently associated with a diminished survival (hazard ratio = 2.36; 95% CI 1.07-5.19; P = 0.0334). In short, age was independently associated with peripheral vascular damage, but so was the presence of damage in other organs (ocular, neuropsychiatric, renal, cardiovascular, pulmonary, musculoskeletal and integument) and some medications (probably reflecting more severe disease). Peripheral vascular damage also negatively affected survival.

  11. Psychological distress, depression, anxiety, and burnout among international humanitarian aid workers: a longitudinal study.

    PubMed

    Lopes Cardozo, Barbara; Gotway Crawford, Carol; Eriksson, Cynthia; Zhu, Julia; Sabin, Miriam; Ager, Alastair; Foy, David; Snider, Leslie; Scholte, Willem; Kaiser, Reinhard; Olff, Miranda; Rijnen, Bas; Simon, Winnifred

    2012-01-01

    International humanitarian aid workers providing care in emergencies are subjected to numerous chronic and traumatic stressors. To examine consequences of such experiences on aid workers' mental health and how the impact is influenced by moderating variables. We conducted a longitudinal study in a sample of international non-governmental organizations. Study outcomes included anxiety, depression, burnout, and life and job satisfaction. We performed bivariate regression analyses at three time points. We fitted generalized estimating equation multivariable regression models for the longitudinal analyses. Study participants from 19 NGOs were assessed at three time points: 212 participated at pre-deployment; 169 (80%) post-deployment; and 154 (73%) within 3-6 months after deployment. Prior to deployment, 12 (3.8%) participants reported anxiety symptoms, compared to 20 (11.8%) at post-deployment (p = 0.0027); 22 (10.4%) reported depression symptoms, compared to 33 (19.5%) at post-deployment (p = 0.0117) and 31 (20.1%) at follow-up (p = .00083). History of mental illness (adjusted odds ratio [AOR] 4.2; 95% confidence interval [CI] 1.45-12.50) contributed to an increased risk for anxiety. The experience of extraordinary stress was a contributor to increased risk for burnout depersonalization (AOR 1.5; 95% CI 1.17-1.83). Higher levels of chronic stress exposure during deployment were contributors to an increased risk for depression (AOR 1.1; 95% CI 1.02-1.20) comparing post- versus pre-deployment, and increased risk for burnout emotional exhaustion (AOR 1.1; 95% CI 1.04-1.19). Social support was associated with lower levels of depression (AOR 0.9; 95% CI 0.84-0.95), psychological distress (AOR = 0.9; [CI] 0.85-0.97), burnout lack of personal accomplishment (AOR 0.95; 95% CI 0.91-0.98), and greater life satisfaction (p = 0.0213). When recruiting and preparing aid workers for deployment, organizations should consider history of mental illness and take steps to decrease chronic stressors, and strengthen social support networks.

  12. The longitudinal relationship of sexual function and androgen status in older men: the Concord Health and Ageing in Men Project.

    PubMed

    Hsu, Benjumin; Cumming, Robert G; Blyth, Fiona M; Naganathan, Vasi; Le Couteur, David G; Seibel, Markus J; Waite, Louise M; Handelsman, David J

    2015-04-01

    It is unclear whether declining sexual function in older men is a cause or consequence of reduced androgen status. Longitudinal associations were examined between reproductive hormones and sexual function in older men. Men aged 70 years and older from the Concord Health and Ageing in Men Project study were assessed at baseline (n = 1705) and 2-year follow-up (n = 1367), with a total of 1226 men included in the final analyses. At both visits, serum testosterone (T), dihydrotestosterone (DHT), estradiol (E2), and estrone (E1) were measured by liquid chromatography-tandem mass spectrometry, and SHBG, LH, and FSH were measured by immunoassay. Sexual functions (erectile function, sexual activity, and sexual desire) were self-reported via standardized questions. In longitudinal analyses, although baseline hormones (T, DHT, E2, and E1) did not predict decline in sexual function, the decline in serum T (but not DHT, E2, or E1) over 2 years was strongly related to the change in sexual activity and desire (but not erectile function). For each 1-SD decrease in T from baseline to 2-year follow-up, there was a multivariate-adjusted odds ratio of 1.23 (95% confidence interval, 1.12-1.36) for an additional risk of further decline in sexual activity. However, the magnitude of the decrease in serum T was strikingly small (<10%). Similar associations were found for changes over 2 years in serum T and decline in sexual desire, but not for erectile function. We found a consistent association among older men followed over 2 years between the decline in sexual activity and desire, but not in erectile function, with a decrease in serum T. Although these observational findings cannot determine causality, the small magnitude of the decrease in serum T raises the hypothesis that reduced sexual function may reduce serum T rather than the reverse.

  13. Low health literacy predicts decline in physical function among older adults: findings from the LitCog cohort study

    PubMed Central

    Smith, Samuel G; O'Conor, Rachel; Curtis, Laura M; Waite, Katie; Deary, Ian J; Paasche-Orlow, Michael; Wolf, Michael S

    2015-01-01

    Background Limited health literacy is associated with worse physical function in cross-sectional studies. We aimed to determine if health literacy is a risk factor for decline in physical function among older adults. Methods A longitudinal cohort of 529 community-dwelling American adults aged 55–74 years were recruited from an academic general internal medicine clinic and federally qualified health centres in 2008–2011. Health literacy (Newest Vital Sign), age, gender, race, education, chronic conditions, body mass index, alcohol consumption, smoking status and exercise frequency were included in multivariable analyses. The 10-item PROMIS (Patient-Reported Outcomes Measurement Information System) physical function scale was assessed at baseline and follow-up (mean=3.2 years, SD=0.39). Results Nearly half of the sample (48.2%) had either marginal (25.5%) or low health literacy (22.7%). Average physical function at baseline was 83.2 (SD=16.6) of 100, and health literacy was associated with poorer baseline physical function in multivariable analysis (p=0.004). At follow-up, physical function declined to 81.9 (SD=17.3; p=0.006) and 20.5% experienced a meaningful decline (>0.5 SD of baseline score). In multivariable analyses, participants with marginal (OR 2.62; 95%CI 1.38 to 4.95; p=0.003) and low (OR 2.57; 95%CI 1.22 to 5.44; p=0.013) health literacy were more likely to experience meaningful decline in physical function than the adequate health literacy group. Entering cognitive abilities to these models did not substantially attenuate effect sizes. Health literacy attenuated the relationship between black race and decline in physical function by 32.6%. Conclusions Lower health literacy increases the risk of exhibiting faster physical decline over time among older adults. Strategies that reduce literacy disparities should be designed and evaluated. PMID:25573701

  14. Development of adolescents' peer crowd identification in relation to changes in problem behaviors.

    PubMed

    Doornwaard, Suzan M; Branje, Susan; Meeus, Wim H J; ter Bogt, Tom F M

    2012-09-01

    This 5-wave longitudinal study, which included 1,313 Dutch adolescents, examined the development of peer crowd identification in relation to changes in problem behaviors. Adolescents from 2 age cohorts annually reported their identification with 7 peer crowds and their levels of internalizing and externalizing problem behaviors. Univariate latent growth curve analyses revealed declines (i.e., "Hip Hoppers" and "Metal Heads") or declines followed by stabilization (i.e., "Nonconformists") in identification with nonconventional crowds and increases (i.e., "Elites" and "Brains") or declines followed by stabilization (i.e., "Normals" and "Jocks") in identification with conventional crowds. Multivariate latent growth curve analyses indicated that stronger and more persistent identifications with nonconventional crowds were generally associated with more problem behaviors throughout adolescence. In contrast, stronger and more persistent identifications with conventional crowds were generally associated with fewer problem behaviors throughout adolescence with the notable exception of Brains, who showed a mixed pattern. Though characterized by fewer externalizing problems, this group did report more anxiety problems. These findings and their implications are discussed. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  15. SOCR Motion Charts: An Efficient, Open-Source, Interactive and Dynamic Applet for Visualizing Longitudinal Multivariate Data

    PubMed Central

    Al-Aziz, Jameel; Christou, Nicolas; Dinov, Ivo D.

    2011-01-01

    The amount, complexity and provenance of data have dramatically increased in the past five years. Visualization of observed and simulated data is a critical component of any social, environmental, biomedical or scientific quest. Dynamic, exploratory and interactive visualization of multivariate data, without preprocessing by dimensionality reduction, remains a nearly insurmountable challenge. The Statistics Online Computational Resource (www.SOCR.ucla.edu) provides portable online aids for probability and statistics education, technology-based instruction and statistical computing. We have developed a new Java-based infrastructure, SOCR Motion Charts, for discovery-based exploratory analysis of multivariate data. This interactive data visualization tool enables the visualization of high-dimensional longitudinal data. SOCR Motion Charts allows mapping of ordinal, nominal and quantitative variables onto time, 2D axes, size, colors, glyphs and appearance characteristics, which facilitates the interactive display of multidimensional data. We validated this new visualization paradigm using several publicly available multivariate datasets including Ice-Thickness, Housing Prices, Consumer Price Index, and California Ozone Data. SOCR Motion Charts is designed using object-oriented programming, implemented as a Java Web-applet and is available to the entire community on the web at www.socr.ucla.edu/SOCR_MotionCharts. It can be used as an instructional tool for rendering and interrogating high-dimensional data in the classroom, as well as a research tool for exploratory data analysis. PMID:21479108

  16. Multivariate test power approximations for balanced linear mixed models in studies with missing data.

    PubMed

    Ringham, Brandy M; Kreidler, Sarah M; Muller, Keith E; Glueck, Deborah H

    2016-07-30

    Multilevel and longitudinal studies are frequently subject to missing data. For example, biomarker studies for oral cancer may involve multiple assays for each participant. Assays may fail, resulting in missing data values that can be assumed to be missing completely at random. Catellier and Muller proposed a data analytic technique to account for data missing at random in multilevel and longitudinal studies. They suggested modifying the degrees of freedom for both the Hotelling-Lawley trace F statistic and its null case reference distribution. We propose parallel adjustments to approximate power for this multivariate test in studies with missing data. The power approximations use a modified non-central F statistic, which is a function of (i) the expected number of complete cases, (ii) the expected number of non-missing pairs of responses, or (iii) the trimmed sample size, which is the planned sample size reduced by the anticipated proportion of missing data. The accuracy of the method is assessed by comparing the theoretical results to the Monte Carlo simulated power for the Catellier and Muller multivariate test. Over all experimental conditions, the closest approximation to the empirical power of the Catellier and Muller multivariate test is obtained by adjusting power calculations with the expected number of complete cases. The utility of the method is demonstrated with a multivariate power analysis for a hypothetical oral cancer biomarkers study. We describe how to implement the method using standard, commercially available software products and give example code. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  17. Comparative multivariate analyses of transient otoacoustic emissions and distorsion products in normal and impaired hearing.

    PubMed

    Stamate, Mirela Cristina; Todor, Nicolae; Cosgarea, Marcel

    2015-01-01

    The clinical utility of otoacoustic emissions as a noninvasive objective test of cochlear function has been long studied. Both transient otoacoustic emissions and distorsion products can be used to identify hearing loss, but to what extent they can be used as predictors for hearing loss is still debated. Most studies agree that multivariate analyses have better test performances than univariate analyses. The aim of the study was to determine transient otoacoustic emissions and distorsion products performance in identifying normal and impaired hearing loss, using the pure tone audiogram as a gold standard procedure and different multivariate statistical approaches. The study included 105 adult subjects with normal hearing and hearing loss who underwent the same test battery: pure-tone audiometry, tympanometry, otoacoustic emission tests. We chose to use the logistic regression as a multivariate statistical technique. Three logistic regression models were developed to characterize the relations between different risk factors (age, sex, tinnitus, demographic features, cochlear status defined by otoacoustic emissions) and hearing status defined by pure-tone audiometry. The multivariate analyses allow the calculation of the logistic score, which is a combination of the inputs, weighted by coefficients, calculated within the analyses. The accuracy of each model was assessed using receiver operating characteristics curve analysis. We used the logistic score to generate receivers operating curves and to estimate the areas under the curves in order to compare different multivariate analyses. We compared the performance of each otoacoustic emission (transient, distorsion product) using three different multivariate analyses for each ear, when multi-frequency gold standards were used. We demonstrated that all multivariate analyses provided high values of the area under the curve proving the performance of the otoacoustic emissions. Each otoacoustic emission test presented high values of area under the curve, suggesting that implementing a multivariate approach to evaluate the performances of each otoacoustic emission test would serve to increase the accuracy in identifying the normal and impaired ears. We encountered the highest area under the curve value for the combined multivariate analysis suggesting that both otoacoustic emission tests should be used in assessing hearing status. Our multivariate analyses revealed that age is a constant predictor factor of the auditory status for both ears, but the presence of tinnitus was the most important predictor for the hearing level, only for the left ear. Age presented similar coefficients, but tinnitus coefficients, by their high value, produced the highest variations of the logistic scores, only for the left ear group, thus increasing the risk of hearing loss. We did not find gender differences between ears for any otoacoustic emission tests, but studies still debate this question as the results are contradictory. Neither gender, nor environment origin had any predictive value for the hearing status, according to the results of our study. Like any other audiological test, using otoacoustic emissions to identify hearing loss is not without error. Even when applying multivariate analysis, perfect test performance is never achieved. Although most studies demonstrated the benefit of using the multivariate analysis, it has not been incorporated into clinical decisions maybe because of the idiosyncratic nature of multivariate solutions or because of the lack of the validation studies.

  18. Comparative multivariate analyses of transient otoacoustic emissions and distorsion products in normal and impaired hearing

    PubMed Central

    STAMATE, MIRELA CRISTINA; TODOR, NICOLAE; COSGAREA, MARCEL

    2015-01-01

    Background and aim The clinical utility of otoacoustic emissions as a noninvasive objective test of cochlear function has been long studied. Both transient otoacoustic emissions and distorsion products can be used to identify hearing loss, but to what extent they can be used as predictors for hearing loss is still debated. Most studies agree that multivariate analyses have better test performances than univariate analyses. The aim of the study was to determine transient otoacoustic emissions and distorsion products performance in identifying normal and impaired hearing loss, using the pure tone audiogram as a gold standard procedure and different multivariate statistical approaches. Methods The study included 105 adult subjects with normal hearing and hearing loss who underwent the same test battery: pure-tone audiometry, tympanometry, otoacoustic emission tests. We chose to use the logistic regression as a multivariate statistical technique. Three logistic regression models were developed to characterize the relations between different risk factors (age, sex, tinnitus, demographic features, cochlear status defined by otoacoustic emissions) and hearing status defined by pure-tone audiometry. The multivariate analyses allow the calculation of the logistic score, which is a combination of the inputs, weighted by coefficients, calculated within the analyses. The accuracy of each model was assessed using receiver operating characteristics curve analysis. We used the logistic score to generate receivers operating curves and to estimate the areas under the curves in order to compare different multivariate analyses. Results We compared the performance of each otoacoustic emission (transient, distorsion product) using three different multivariate analyses for each ear, when multi-frequency gold standards were used. We demonstrated that all multivariate analyses provided high values of the area under the curve proving the performance of the otoacoustic emissions. Each otoacoustic emission test presented high values of area under the curve, suggesting that implementing a multivariate approach to evaluate the performances of each otoacoustic emission test would serve to increase the accuracy in identifying the normal and impaired ears. We encountered the highest area under the curve value for the combined multivariate analysis suggesting that both otoacoustic emission tests should be used in assessing hearing status. Our multivariate analyses revealed that age is a constant predictor factor of the auditory status for both ears, but the presence of tinnitus was the most important predictor for the hearing level, only for the left ear. Age presented similar coefficients, but tinnitus coefficients, by their high value, produced the highest variations of the logistic scores, only for the left ear group, thus increasing the risk of hearing loss. We did not find gender differences between ears for any otoacoustic emission tests, but studies still debate this question as the results are contradictory. Neither gender, nor environment origin had any predictive value for the hearing status, according to the results of our study. Conclusion Like any other audiological test, using otoacoustic emissions to identify hearing loss is not without error. Even when applying multivariate analysis, perfect test performance is never achieved. Although most studies demonstrated the benefit of using the multivariate analysis, it has not been incorporated into clinical decisions maybe because of the idiosyncratic nature of multivariate solutions or because of the lack of the validation studies. PMID:26733749

  19. Volunteering is associated with increased survival in able-bodied participants of the English Longitudinal Study of Ageing.

    PubMed

    Rogers, Nina Trivedy; Demakakos, Panayotes; Taylor, Mark Steven; Steptoe, Andrew; Hamer, Mark; Shankar, Aparna

    2016-06-01

    Volunteering has been linked to reduced mortality in older adults, but the mechanisms explaining this effect remain unclear. This study investigated whether volunteering is associated with increased survival in participants of the English Longitudinal Study of Ageing and whether differences in survival are modified by functional disabilities. A multivariate Cox Proportional Hazards model was used to estimate the association of volunteering with survival over a period of 10.9 years in 10 324 participants, while controlling for selected confounders. To investigate effect modification by disability, the analyses were repeated in participants with and without self-reported functional disabilities. Volunteering was associated with a reduced probability of death from all causes in univariate analyses (HR=0.65, CI 0.58 to 0.73, p<0.0001), but adjustment for covariates rendered this association non-significant (HR=0.90, CI 0.79 to 1.01, p=0.07). Able-bodied volunteers had significantly increased survival compared with able-bodied non-volunteers (HR=0.81, 95% CI 0.69 to 0.95, p=0.009). There was no significant survival advantage among disabled volunteers, compared with disabled non-volunteers (HR=1.06, CI 0.88 to 1.29, p=0.53). Volunteering is associated with reduced mortality in older adults in England, but this effect appears to be limited to volunteers who report no disabilities. 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/

  20. Negative perceptions of ageing predict the onset and persistence of depression and anxiety: Findings from a prospective analysis of the Irish Longitudinal Study on Ageing (TILDA).

    PubMed

    Freeman, Aislinné Theresa; Santini, Ziggi Ivan; Tyrovolas, Stefanos; Rummel-Kluge, Christine; Haro, Josep Maria; Koyanagi, Ai

    2016-07-15

    Although there is a growing literature on the adverse health outcomes related with negative ageing perceptions, studies on their association with mental disorders such as depression and anxiety are scarce. Thus, the aim of the current study was to prospectively assess the association between negative ageing perceptions and incident/persistent depression and anxiety using nationally representative data from Ireland. Data from two consecutive waves of the Irish Longitudinal Study on Ageing (TILDA) were analysed. The analytical sample consisted of 6095 adults aged ≥50 years. Validated scales for negative ageing perceptions, depression, and anxiety were used. Multivariable logistic regression analyses were used to assess the association between negative ageing perceptions at baseline and the onset and persistence of depression and anxiety at two-year follow up. After adjusting for potential confounders, negative ageing perceptions at baseline predicted the new onset of depression and anxiety at follow-up. Among those with depression or anxiety at baseline, negative ageing perceptions also predicted the persistence of these conditions at follow-up. Baseline data on negative ageing perceptions were used for the analysis and it is possible that scores could have changed over time. Addressing negative perceptions towards ageing by developing interventions that activate positive ageing perceptions, and target societal attitudes by means of policy change, public campaigns, and community education programmes, may shift social perceptions and reduce the burden of depression and anxiety among the elderly. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  1. Smoking habits and leukocyte telomere length dynamics among older adults: Results from the ESTHER cohort.

    PubMed

    Müezzinler, Aysel; Mons, Ute; Dieffenbach, Aida Karina; Butterbach, Katja; Saum, Kai-Uwe; Schick, Matthias; Stammer, Hermann; Boukamp, Petra; Holleczek, Bernd; Stegmaier, Christa; Brenner, Hermann

    2015-10-01

    Leukocyte telomere length (LTL) shortens with age and short LTL has been associated with increased mortality and increased risk for some age-related outcomes. This study aims to analyse the associations of smoking habits with LTL and rate of LTL change per year in older adults. LTL was measured by quantitative PCR at baseline in 3600 older adults, who were enrolled in a population-based cohort study in Germany. For longitudinal analyses, measurements were repeated in blood samples obtained at 8-year follow-up from 1000 participants. Terminal Restriction Fragment analysis was additionally performed in a sub-sample to obtain absolute LTL in base pairs. Multivariate linear regression models were used to estimate associations of smoking habits with baseline LTL and changes in LTL over time. LTL was inversely associated with age (r=-0.090, p<0.0001). Women had longer LTL than men (p<0.0001). Smoking was inversely associated with LTL. On average, current smokers had 73 base pairs (BP) shorter LTL compared to never smokers. Smoking intensity and pack-years of smoking were also inversely associated with LTL, and a positive association was observed with years since smoking cessation. Slower LTL attrition rates were observed in ever smokers over 8years of follow-up. Our cross-sectional analysis supports suggestions that smoking might contribute to shortening of LTL but this relationship could not be shown longitudinally. The overall rather small effect sizes observed for smoking-related variables suggest that LTL reflects smoking-related health hazards only to a very limited extent. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Disease Activity and Damage are not Associated with Increased Levels of Fatigue in Systemic Lupus Erythematosus Patients from LUMINA LXVII, a Multiethnic Cohort

    PubMed Central

    Burgos, Paula I.; Alarcón, Graciela S.; McGwin, Gerald; Crews, Kendra Q.; Reveille, John D.; Vilá, Luis M.

    2009-01-01

    Objective To determine the factors associated with increased levels of fatigue over the course of the disease in systemic lupus erythematosus (SLE) patients from LUMINA (Lupus in Minorities: Nature versus Nurture), a longitudinal multiethnic cohort. Methods Patients with SLE (American College of Rheumatology revised and updated criteria), age ≥16 years, disease duration ≤ 5 years at entry into the cohort (T0), of Hispanic (Texan or Puerto Rican), African America or Caucasian ethnicity, were studied. The association between socioeconomic-demographic, health behaviors, behavioral and psychological, functional and clinical characteristics and fatigue was examined using generalized estimating equations to account for the longitudinal nature of the data. Results Five-hundred and fifteen patients (~91% female) contributed 2,609 visits to these analyses; there were: 93 (18.1%) Texan Hispanics, 101 (19.6%) Puerto Rican Hispanics, 169 (32.8%) African Americans, and 152 (29.5%) Caucasians; the patients mean (SD) age and follow up time were 37.2 (12.0) and 4.7 (3.2) years, respectively. Variables associated with increased levels of fatigue in the multivariable analyses were Caucasian ethnicity, the presence of constitutional symptoms(fever, weight loss), higher levels of pain, of abnormal illness-related behaviors and of helplessness (p’s between 0.0018 and <0.0001). Conclusions The presence of pain, abnormal illness-related behaviors, helplessness and constitutional manifestations were associated with increased levels of fatigue; however, lupus specific measures, such as disease activity and damage were not. Interventions aimed at decreasing fatigue need to take into account these findings. PMID:19714612

  3. Psychological and Relational Correlates of Intimate Partner Violence Profiles Among Pregnant Adolescent Couples

    PubMed Central

    Lewis, Jessica B.; Sullivan, Tami P.; Angley, Meghan; Callands, Tamora; Divney, Anna A.; Magriples, Urania; Gordon, Derrick M.; Kershaw, Trace S.

    2017-01-01

    We sought to identify relationship and individual psychological factors that related to four profiles of intimate partner violence (IPV) among pregnant adolescent couples: no IPV, male IPV victim only, female IPV victim only, mutual IPV, and how associations differ by sex. Using data from a longitudinal study of pregnant adolescents and partners (n = 291 couples), we used a multivariate profile analysis using multivariate analysis of covariance with between and within-subjects effects to compare IPV groups and sex on relationship and psychological factors. Analyses were conducted at the couple level, with IPV groups as a between-subjects couple level variable and sex as a within-subjects variable that allowed us to model and compare the outcomes of both partners while controlling for the correlated nature of the data. Analyses controlled for age, race, income, relationship duration, and gestational age. Among couples, 64% had no IPV; 23% male IPV victim only; 7% mutual IPV; 5% female IPV victim only. Relationship (F = 3.61, P < .001) and psychological (F = 3.17, P < .001) factors differed by IPV group, overall. Attachment anxiety, attachment avoidance, relationship equity, perceived partner infidelity, depression, stress, and hostility each differed by IPV profile (all P < .01). Attachment anxiety, equity, depression and stress had a significant IPV profile by sex interaction (all P < .05). Couples with mutual IPV had the least healthy relationship and psychological characteristics; couples with no IPV had the healthiest characteristics. Females in mutually violent relationships were at particularly high risk. Couple-level interventions focused on relational issues might protect young families from developing IPV behaviors. PMID:27135634

  4. The Association Between Prepregnancy Parental Support and Control and Adolescent Girls’ Pregnancy Resolution Decisions

    PubMed Central

    Madkour, Aubrey Spriggs; Xie, Yiqiong; Harville, Emily W.

    2013-01-01

    Purpose To examine the influence of prepregnancy parental support and control on adolescent girls’ pregnancy resolution decisions. Methods Data from the National Longitudinal Study of Adolescent Health were analyzed. Girls whose first pregnancy reported in wave IV occurred after wave I and before age 20 were included (n = 1,107). Participants self-reported pregnancy disposition (abortion, ectopic or tubal pregnancy, miscarriage, stillbirth, live birth) for each pregnancy; responses were dichotomized as abortion versus other. Girls’ perceptions of parental support and control were measured at wave I. Controls were included for wave I age, age at pregnancy, year at the end of pregnancy, race/ethnicity, and parent characteristics (i.e., education, religious affiliation, age at first marriage, and educational expectations). Weighted multivariable logistic regression models were performed. Results Approximately 18% of girls reporting a teen pregnancy reported having an abortion. In crude analyses, parental support was marginally negatively related to abortion (odds ratio [OR] =.83, p =.06) and parental control was significantly negatively related to abortion (OR = .78, p = .02). In multivariable analyses, higher parental control was significantly negatively related to abortion versus other pregnancy outcomes (adjusted OR .80, 95% confidence interval .66–.98). Perceived parental support was unassociated with pregnancy resolution decisions. The only other factor associated with abortion decisions was parent education: odds of choosing abortion versus other pregnancy outcomes were significantly higher for adolescent girls whose parents had a bachelor’s degree or greater versus those with lower educational attainment. Conclusions Pregnant adolescents with less educated parents or parents exercising greater control were less likely to have an abortion. PMID:23763966

  5. Intimate partner violence among economically disadvantaged young adult women: associations with adolescent risk-taking and pregnancy experiences.

    PubMed

    O'Donnell, Lydia; Agronick, Gail; Duran, Richard; Myint-U, Athi; Stueve, Ann

    2009-06-01

    Intimate partner violence negatively impacts the health of substantial proportions of young women in economically disadvantaged communities, where sexual initiation, aggressive behaviors, unintended pregnancies and childbearing are common among adolescents. It is therefore important to assess how adolescent risk behaviors and pregnancy experiences are linked to such violence during young adulthood. Data from 526 participants in the Reach for Health Longitudinal Study who were surveyed during middle school (in 1995-1996 and 1996-1997) and at ages 22-25 (in 2005-2007) provided information on adolescent risk behaviors and pregnancy experiences, as well as experiences of intimate partner violence during young adulthood. Bivariate and multivariate analyses were conducted to identify correlates of intimate partner violence involvement. As young adults, 29% of women reported having been victims of intimate partner violence in the past 12 months; 21% reported having perpetrated such violence. In multivariate analyses, victimization and perpetration in the last year are positively associated with aggressive behavior in middle school (odds ratios, 1.9 and 2.5, respectively), lifetime number of sex partners (1.3 for both) and having a history of unintended pregnancy or pregnancy problems (1.3 for both). Perpetration also is associated with early sexual initiation (0.5) and living with a partner (1.8). It is important to consider women's pregnancy histories in programs aimed at preventing the adverse outcomes of relationship violence and in screening for partner violence in sexual and reproductive health services. Early intervention may help women develop the skills needed for resolving conflicts with peers and partners.

  6. Associations of Social Support, Friends Only Known Through the Internet, and Health-Related Quality of Life with Internet Gaming Disorder in Adolescence.

    PubMed

    Wartberg, Lutz; Kriston, Levente; Kammerl, Rudolf

    2017-07-01

    Internet Gaming Disorder (IGD) has been included in the current edition of the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition (DSM-5). In the present study, the relationship among social support, friends only known through the Internet, health-related quality of life, and IGD in adolescence was explored for the first time. For this purpose, 1,095 adolescents aged from 12 to 14 years were surveyed with a standardized questionnaire concerning IGD, self-perceived social support, proportion of friends only known through the Internet, and health-related quality of life. The authors conducted unpaired t-tests, a chi-square test, as well as correlation and logistic regression analyses. According to the statistical analyses, adolescents with IGD reported lower self-perceived social support, more friends only known through the Internet, and a lower health-related quality of life compared with the group without IGD. Both in bivariate and multivariate logistic regression models, statistically significant associations between IGD and male gender, a higher proportion of friends only known through the Internet, and a lower health-related quality of life (multivariate model: Nagelkerke's R 2  = 0.37) were revealed. Lower self-perceived social support was related to IGD in the bivariate model only. In summary, quality of life and social aspects seem to be important factors for IGD in adolescence and therefore should be incorporated in further (longitudinal) studies. The findings of the present survey may provide starting points for the development of prevention and intervention programs for adolescents affected by IGD.

  7. Sexual functioning among early post-treatment breast cancer survivors.

    PubMed

    Avis, Nancy E; Johnson, Aimee; Canzona, Mollie Rose; Levine, Beverly J

    2018-02-17

    This study aims (1) to estimate percentages of partnered women who are sexually active over the first 2 years post-breast cancer diagnosis; (2) to identify factors related to sexual inactivity; and (3) to evaluate separately, among both sexually active and inactive survivors, the relation between sexual problems and treatment-related variables, symptoms, and psychosocial factors. Longitudinal observational study of breast cancer survivors recruited within 8 months of cancer diagnosis and followed for 18 months. The main outcome measures were (1) being sexually active/inactive in the past month and (2) sexual problems assessed with the four-item sexual problem domain of the Quality of Life in Adult Cancer Survivors (QLACS) scale. At baseline, 52.4% of women reported being sexually active in the past month. This percentage increased to 60.7% 18 months later. In multivariable repeated-measures analyses, age, past chemotherapy, depressive symptoms, and lower perceived attractiveness were related to inactivity. Sexually inactive women reported more problems on the QLACS than sexually active women. In stratified multivariable analyses, depressive symptoms were related to greater sexual problems for both sexually active and inactive women, as was vaginal dryness. Among the sexually active women, younger age at diagnosis, less illness intrusiveness, and lower perceived attractiveness were related to more problems. Research has shown that sexual functioning/sexual health are key aspects of quality of life for many cancer survivors, and are often not addressed by health care providers. Future studies should examine how such topics are handled by clinicians in their interactions with survivors.

  8. Cross-Sectional Analysis of Longitudinal Mediation Processes.

    PubMed

    O'Laughlin, Kristine D; Martin, Monica J; Ferrer, Emilio

    2018-01-01

    Statistical mediation analysis can help to identify and explain the mechanisms behind psychological processes. Examining a set of variables for mediation effects is a ubiquitous process in the social sciences literature; however, despite evidence suggesting that cross-sectional data can misrepresent the mediation of longitudinal processes, cross-sectional analyses continue to be used in this manner. Alternative longitudinal mediation models, including those rooted in a structural equation modeling framework (cross-lagged panel, latent growth curve, and latent difference score models) are currently available and may provide a better representation of mediation processes for longitudinal data. The purpose of this paper is twofold: first, we provide a comparison of cross-sectional and longitudinal mediation models; second, we advocate using models to evaluate mediation effects that capture the temporal sequence of the process under study. Two separate empirical examples are presented to illustrate differences in the conclusions drawn from cross-sectional and longitudinal mediation analyses. Findings from these examples yielded substantial differences in interpretations between the cross-sectional and longitudinal mediation models considered here. Based on these observations, researchers should use caution when attempting to use cross-sectional data in place of longitudinal data for mediation analyses.

  9. Advertisement and knowledge of tobacco products among Ellisras rural children aged 11 to 18 years: Ellisras Longitudinal study.

    PubMed

    Monyeki, Kotsedi D; Kemper, Han C G; Amusa, Lateef O; Motshwane, Marcus

    2013-08-02

    Tobacco products use is the leading cause of chronic diseases morbidity and mortality. This study explores an exposure to tobacco advertisements factors and knowledge, an association with snuff/pipe usage and cigarette smoking among Ellisras rural children aged between 11 to 18 years. A total of 1654 subjects (854 boys and 800 girls) who were part of the Ellisras Longitudinal Study completed the questionnaire. A significant (p < 0.05) number of boys (11.7%) compared to girls (8.8%) received free cigarettes from the members of the community. Bill boards were successful in advertising tobacco products among the Ellisras rural boys (17% boys and 12.8% for girls, p < 0.022). Multivariate analyses found significant association between cigarette smoking (OR = 1.7 95%CI 1.1-2.7 and Model 2 OR 1.6 95%CI 1.0-2.6 adjusted for age and gender) and advertisements of tobacco products on the TV screens, videos or movies. Exposure to tobacco products advertisements was high among Ellisras rural children. Though tobacco products legislation exists in South Africa, efforts should be taken by the health professionals to emphasize the danger of using tobacco products even among the illiterate. Teachers and parents should refrain from advertising tobacco products at schools and at homes.

  10. Predictors of workplace violence among ambulance personnel: a longitudinal study.

    PubMed

    van der Velden, Peter G; Bosmans, Mark W G; van der Meulen, Erik

    2016-04-01

    To examine predictors of repeated confrontations with workplace violence among ambulance personnel, the proportion of exposure to potentially traumatic events that are aggression-related and to what extent personnel was able to prevent escalations. Although previous research assessed the prevalences among this group, little is known about predictors, to what extent PTE's are WPV-related and their abilities to prevent escalations. A longitudinal study with a 6 months' time interval ( N  =   103). At T1 demographics, workplace violence and potentially traumatic events in the past year, mental health, personality, handling of rules, coping and social organizational stressors were assessed. Confrontations with aggression were also examined at T2. Multivariate logistic regression analyses showed that only problems with superiors independently predicted repeated verbal aggression and that only the (absence of the) ability to compromise very easily predicted repeatedly being on guard and repeatedly confronted with any form of aggression. Due to very low prevalences, we could not examine predictors of repeated confrontations with physical aggression ( N  =   5) and serious threat ( N  =   7). A large majority reported that in most workplace violence cases they could prevent further escalations. About 2% reported a potentially traumatic event in the year before T1 that was WPV related and perceived as very stressful.

  11. Patterns of Alcohol Use and Consequences Among Empirically Derived Sexual Minority Subgroups

    PubMed Central

    Talley, Amelia E.; Sher, Kenneth J.; Steinley, Douglas; Wood, Phillip K.; Littlefield, Andrew K.

    2012-01-01

    Objective: The current study develops an empirically determined classification of sexual orientation developmental patterns based on participants’ annual reports of self-identifications, sexual attractions, and sexual behaviors during the first 4 years of college. A secondary aim of the current work was to examine trajectories of alcohol involvement among identified subgroups. Method: Data were drawn from a subsample of a longitudinal study of incoming first-time college students at a large, public university (n = 2,068). Longitudinal latent class analysis was used to classify sexual minority participants into empirically derived subgroups based on three self-reported facets of sexual orientation. Multivariate repeated-measures analyses were conducted to examine how trajectories of alcohol involvement varied by sexual orientation class membership. Results: Four unique subclasses of sexual orientation developmental patterns were identified for males and females: one consistently exclusively heterosexual group and three sexual minority groups. Despite generally similar alcohol use patterns among subclasses, certain sexual minority subgroups reported elevated levels of alcohol-related negative consequences and maladaptive motivations for use throughout college compared with their exclusively heterosexual counterparts. Conclusions: Elevations in coping and conformity motivations for alcohol use were seen among those subgroups that also evidenced heightened negative alcohol-related consequences. Implications and limitations of the current work are discussed. PMID:22333337

  12. Longitudinal influences of neighbourhood built and social environment on children's weight status.

    PubMed

    Gose, Maria; Plachta-Danielzik, Sandra; Willié, Bianca; Johannsen, Maike; Landsberg, Beate; Müller, Manfred J

    2013-10-15

    The objective was to examine longitudinal 4-year-relationships between neighbourhood social environment and children's body mass index-standard deviation score (BMI-SDS) taking into account the built environment. Furthermore, we have analysed the influence of potential interactions between the social environment and family/social data on children's BMI-SDS. Between 2006-2008 and 2010-2012, anthropometric measurements were conducted among 485 children (age at baseline: 6.1 (5.8-6.4)). Socio-demographic characteristics and perception of residential environment were reported by parents. Geographic Information Systems were used to examine street length, number of food outlets and distance to the nearest playground and park/green space within an 800 m Euclidian buffer of each participant address point. Additional data on neighbourhood characteristics (e.g., traffic density, walkability, crime rates) were obtained from the State Capital of Kiel, Germany. In a multivariate model, walkability, street type, socioeconomic status of the district and perceived frequency of passing trucks/buses were associated with BMI-SDS over 4 years, but only neighbourhood SES had an effect on change in BMI-SDS. However, familial/social factors rather than neighbourhood environment (especially social environment) had an impact on children's BMI-SDS over 4 years. Thus, social inequalities in childhood overweight are only partially explained by social neighbourhood environment.

  13. Disordered eating and weight changes after deployment: longitudinal assessment of a large US military cohort.

    PubMed

    Jacobson, Isabel G; Smith, Tyler C; Smith, Besa; Keel, Pamela K; Amoroso, Paul J; Wells, Timothy S; Bathalon, Gaston P; Boyko, Edward J; Ryan, Margaret A K

    2009-02-15

    The effect of military deployments to combat environments on disordered eating and weight changes is unknown. Using longitudinal data from Millennium Cohort Study participants who completed baseline (2001-2003) and follow-up (2004-2006) questionnaires (n=48,378), the authors investigated new-onset disordered eating and weight changes in a large military cohort. Multivariable logistic regression was used to compare these outcomes among those who deployed and reported combat exposures, those who deployed but did not report combat exposures, and those who did not deploy in support of the wars in Iraq and Afghanistan. Deployment was not significantly associated with new-onset disordered eating in women or men, after adjustment for baseline demographic, military, and behavioral characteristics. However, in subgroup comparison analyses of deployers, deployed women reporting combat exposures were 1.78 times more likely to report new-onset disordered eating (95% confidence interval: 1.02, 3.11) and 2.35 times more likely to lose 10% or more of their body weight compared with women who deployed but did not report combat exposures (95% confidence interval: 1.17, 4.70). Despite no significant overall association between deployment and disordered eating and weight changes, deployed women reporting combat exposures represent a subgroup at higher risk for developing eating problems and weight loss.

  14. Motor impulsivity during childhood and adolescence: a longitudinal biometric analysis of the go/no-go task in 9- to 18-year-old twins.

    PubMed

    Bezdjian, Serena; Tuvblad, Catherine; Wang, Pan; Raine, Adrian; Baker, Laura A

    2014-11-01

    In the present study, we investigated genetic and environmental effects on motor impulsivity from childhood to late adolescence using a longitudinal sample of twins from ages 9 to 18 years. Motor impulsivity was assessed using errors of commission (no-go errors) in a visual go/no-go task at 4 time points: ages 9-10, 11-13, 14-15, and 16-18 years. Significant genetic and nonshared environmental effects on motor impulsivity were found at each of the 4 waves of assessment with genetic factors explaining 22%-41% of the variance within each of the 4 waves. Phenotypically, children's average performance improved across age (i.e., fewer no-go errors during later assessments). Multivariate biometric analyses revealed that common genetic factors influenced 12%-40% of the variance in motor impulsivity across development, whereas nonshared environmental factors common to all time points contributed to 2%-52% of the variance. Nonshared environmental influences specific to each time point also significantly influenced motor impulsivity. Overall, results demonstrated that although genetic factors were critical to motor impulsivity across development, both common and specific nonshared environmental factors played a strong role in the development of motor impulsivity across age. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  15. A retrospective, longitudinal study of factors associated with new antipsychotic medication use among recently admitted long-term care residents.

    PubMed

    Foebel, Andrea; Ballokova, Anna; Wellens, Nathalie I H; Fialova, Daniela; Milisen, Koen; Liperoti, Rosa; Hirdes, John P

    2015-10-19

    Use of antipsychotic (AP) medications is high and often inappropriate among institutionalized populations. Little is known about the correlates of new AP drug use following admission to long-term care (LTC) settings. This study investigated the frequency and correlates of new AP drug use among newly admitted LTC residents. This longitudinal, retrospective study used data from the interRAI - Nursing Home Minimum Data Set version 2.0 (MDS 2.0) instrument. Data about demographic, clinical and social characteristics, and medication use, were collected in Ontario, Canada, from 2003-2011 by trained nurses. Residents with complete admission and 3-6 month follow-up data were included (N = 47,768). Multivariate logistic regression analyses, stratified by gender, explored correlates of new AP drug use upon admission to LTC. New AP drug users comprised 7 % of the final cohort. Severe cognitive impairment, dementia, and motor agitation were significantly associated with new AP drug use among both sexes. Additionally, behavioural problems, conflicts with staff and reduced social engagement were strong correlates of new AP drug use. Social factors were as strongly associated with new AP drug use after LTC admission as clinical factors. Strategies to prevent the potential misuse of AP drugs upon LTC admission should consider the social determinants of such prescribing.

  16. Correlates of Suicidality: Investigation of a Representative Sample of Manitoba First Nations Adolescents

    PubMed Central

    Mota, Natalie; Elias, Brenda; Tefft, Bruce; Medved, Maria; Munro, Garry

    2012-01-01

    Objectives. We examined individual, friend or family, and community or tribe correlates of suicidality in a representative on-reserve sample of First Nations adolescents. Methods. Data came from the 2002–2003 Manitoba First Nations Regional Longitudinal Health Survey of Youth. Interviews were conducted with adolescents aged 12 to 17 years (n = 1125) from 23 First Nations communities in Manitoba. We used bivariate logistic regression analyses to examine the relationships between a range of factors and lifetime suicidality. We conducted sex-by-correlate interactions for each significant correlate at the bivariate level. A multivariate logistic regression analysis identified those correlates most strongly related to suicidality. Results. We found several variables to be associated with an increased likelihood of suicidality in the multivariate model, including being female, depressed mood, abuse or fear of abuse, a hospital stay, and substance use (adjusted odds ratio range = 2.43–11.73). Perceived community caring was protective against suicidality (adjusted odds ratio = 0.93; 95% confidence interval = 0.88, 0.97) in the same model. Conclusions. Results of this study may be important in informing First Nations and government policy related to the implementation of suicide prevention strategies in First Nations communities. PMID:22676500

  17. Biological and socio-cultural factors during the school years predicting women’s lifetime educational attainment

    PubMed Central

    Hendrick, C. Emily; Cohen, Alison K.; Deardorff, Julianna

    2015-01-01

    BACKGROUND Lifetime educational attainment is an important predictor of health and well-being for women in the United States. In the current study, we examine the roles of socio-cultural factors in youth and an understudied biological life event, pubertal timing, in predicting women’s lifetime educational attainment. METHODS Using data from the National Longitudinal Survey of Youth 1997 cohort (N = 3889), we conducted sequential multivariate linear regression analyses to investigate the influences of macro-level and family-level socio-cultural contextual factors in youth (region of country, urbanicity, race/ethnicity, year of birth, household composition, mother’s education, mother’s age at first birth) and early menarche, a marker of early pubertal development, on women’s educational attainment after age 24. RESULTS Pubertal timing and all socio-cultural factors in youth, other than year of birth, predicted women’s lifetime educational attainment in bivariate models. Family factors had the strongest associations. When family factors were added to multivariate models, geographic region in youth and pubertal timing were no longer significant. CONCLUSION Our findings provide additional evidence that family factors should be considered when developing comprehensive and inclusive interventions in childhood and adolescence to promote lifetime educational attainment among girls. PMID:26830508

  18. Association between periodontal flap surgery for periodontitis and vasculogenic erectile dysfunction in Koreans.

    PubMed

    Lee, Jae-Hong; Choi, Jung-Kyu; Kim, Sang-Hyun; Cho, Kyung-Hyun; Kim, Young-Taek; Choi, Seong-Ho; Jung, Ui-Won

    2017-04-01

    The National Health Insurance Service-National Sample Cohort and medical checkup data from 2002 to 2013 were used to evaluate the association between periodontal surgery for the treatment of periodontitis (PSTP) and vasculogenic erectile dysfunction (VED). Bivariate and multivariate logistic regression analyses were applied to a longitudinal retrospective database to assess the association between PSTP and VED while adjusting for the potential confounding effects of sociodemographic factors (age, household income, insurance status, health status, residence area, and smoking status) and comorbidities (diabetes mellitus, angina pectoris, cerebral infarction, and myocardial infarction). Among the 7,148 PSTP within the 268,296 recruited subjects, the overall prevalence of VED in PSTP was 1.43% (n=102). The bivariate analysis showed that VED was significantly related to PSTP (odds ratio [OR], 1.99; 95% confidence interval [CI], 1.38-2.06; P <0.001), and this was confirmed in the multivariate analysis after adjusting for sociodemographic factors and comorbidities (OR, 1.29; 95% CI, 1.06-1.58; P =0.002). Subjects with a history of periodontal flap surgery had a significantly higher risk of VED, after adjusting for potential confounding factors. Further studies are required to identify the key mechanisms underlying the association between severe periodontal disease and VED.

  19. Association between periodontal flap surgery for periodontitis and vasculogenic erectile dysfunction in Koreans

    PubMed Central

    2017-01-01

    Purpose The National Health Insurance Service-National Sample Cohort and medical checkup data from 2002 to 2013 were used to evaluate the association between periodontal surgery for the treatment of periodontitis (PSTP) and vasculogenic erectile dysfunction (VED). Methods Bivariate and multivariate logistic regression analyses were applied to a longitudinal retrospective database to assess the association between PSTP and VED while adjusting for the potential confounding effects of sociodemographic factors (age, household income, insurance status, health status, residence area, and smoking status) and comorbidities (diabetes mellitus, angina pectoris, cerebral infarction, and myocardial infarction). Results Among the 7,148 PSTP within the 268,296 recruited subjects, the overall prevalence of VED in PSTP was 1.43% (n=102). The bivariate analysis showed that VED was significantly related to PSTP (odds ratio [OR], 1.99; 95% confidence interval [CI], 1.38–2.06; P<0.001), and this was confirmed in the multivariate analysis after adjusting for sociodemographic factors and comorbidities (OR, 1.29; 95% CI, 1.06–1.58; P=0.002). Conclusions Subjects with a history of periodontal flap surgery had a significantly higher risk of VED, after adjusting for potential confounding factors. Further studies are required to identify the key mechanisms underlying the association between severe periodontal disease and VED. PMID:28462008

  20. Intakes of caffeine, coffee and tea and risk of amyotrophic lateral sclerosis: Results from five cohort studies.

    PubMed

    Fondell, Elinor; O'Reilly, É Ilis J; Fitzgerald, Kathryn C; Falcone, Guido J; Kolonel, Laurence N; Park, Yikyung; Gapstur, Susan M; Ascherio, Alberto

    2015-01-01

    Caffeine is thought to be neuroprotective by antagonizing the adenosine A2A receptors in the brain and thereby protecting motor neurons from excitotoxicity. We examined the association between consumption of caffeine, coffee and tea and risk of amyotrophic lateral sclerosis (ALS). Longitudinal analyses based on over 1,010,000 males and females in five large cohort studies (the Nurses' Health Study, the Health Professionals Follow-up Study, the Cancer Prevention Study II Nutrition Cohort, the Multiethnic Cohort Study, and the National Institutes of Health-AARP Diet and Health Study). Cohort-specific multivariable-adjusted risk ratios (RR) and 95% confidence intervals (CI) estimates of ALS incidence or death were estimated by Cox proportional hazards regression and pooled using random-effects models. Results showed that a total of 1279 cases of ALS were documented during a mean of 18 years of follow-up. Caffeine intake was not associated with ALS risk; the pooled multivariable-adjusted RR comparing the highest to the lowest quintile of intake was 0.96 (95% CI 0.81-1.16). Similarly, neither coffee nor tea was associated with ALS risk. In conclusion, the results of this large study do not support associations of caffeine or caffeinated beverages with ALS risk.

  1. Intakes of caffeine, coffee and tea and risk of Amyotrophic Lateral Sclerosis: Results from five cohort studies

    PubMed Central

    Fondell, Elinor; O'Reilly, Éilis J.; Fitzgerald, Kathryn C.; Falcone, Guido J.; Kolonel, Laurence N.; Park, Yikyung; Gapstur, Susan M.; Ascherio, Alberto

    2015-01-01

    Objective Caffeine is thought to be neuroprotective by antagonizing the adenosine A2A receptors in the brain and thereby protecting motor neurons from excitotoxicity. We examined the association between consumption of caffeine, coffee and tea and risk of Amyotrophic Lateral Sclerosis (ALS). Methods Longitudinal analyses based on over 1 010 000 men and women in 5 large cohort studies [the Nurses’ Health Study, the Health Professionals Follow-up Study, the Cancer Prevention Study II Nutrition Cohort, the Multiethnic Cohort Study, and the National Institutes of Health – AARP Diet and Health Study]. Cohort-specific multivariable-adjusted risk ratios (RR) and 95% confidence intervals (CI) estimates of ALS incidence or death was estimated by Cox proportional hazards regression and pooled using random-effects models. Results A total of 1279 cases of ALS were documented during a mean of 18 years of follow-up. Caffeine intake was not associated with ALS risk; the pooled multivariable-adjusted RR comparing the highest to the lowest quintile of intake was 0.96 (95% CI 0.81-1.16). Similarly, neither coffee nor tea was associated with ALS risk. Conclusion The results of this large study do not support associations of caffeine or caffeinated beverages with ALS risk. PMID:25822002

  2. Sampling effort affects multivariate comparisons of stream assemblages

    USGS Publications Warehouse

    Cao, Y.; Larsen, D.P.; Hughes, R.M.; Angermeier, P.L.; Patton, T.M.

    2002-01-01

    Multivariate analyses are used widely for determining patterns of assemblage structure, inferring species-environment relationships and assessing human impacts on ecosystems. The estimation of ecological patterns often depends on sampling effort, so the degree to which sampling effort affects the outcome of multivariate analyses is a concern. We examined the effect of sampling effort on site and group separation, which was measured using a mean similarity method. Two similarity measures, the Jaccard Coefficient and Bray-Curtis Index were investigated with 1 benthic macroinvertebrate and 2 fish data sets. Site separation was significantly improved with increased sampling effort because the similarity between replicate samples of a site increased more rapidly than between sites. Similarly, the faster increase in similarity between sites of the same group than between sites of different groups caused clearer separation between groups. The strength of site and group separation completely stabilized only when the mean similarity between replicates reached 1. These results are applicable to commonly used multivariate techniques such as cluster analysis and ordination because these multivariate techniques start with a similarity matrix. Completely stable outcomes of multivariate analyses are not feasible. Instead, we suggest 2 criteria for estimating the stability of multivariate analyses of assemblage data: 1) mean within-site similarity across all sites compared, indicating sample representativeness, and 2) the SD of within-site similarity across sites, measuring sample comparability.

  3. Adolescent precursors of adult borderline personality pathology in a high-risk community sample.

    PubMed

    Conway, Christopher C; Hammen, Constance; Brennan, Patricia A

    2015-06-01

    Longitudinal studies of the exact environmental conditions and personal attributes contributing to the development of borderline personality disorder (BPD) are rare. Furthermore, existing research typically examines risk factors in isolation, limiting our knowledge of the relative effect sizes of different risk factors and how they act in concert to bring about borderline personality pathology. The present study investigated the prospective effects of diverse acute and chronic stressors, proband psychopathology, and maternal psychopathology on BPD features in a high-risk community sample (N = 700) of youth followed from mid-adolescence to young adulthood. Multivariate analyses revealed significant effects of maternal externalizing disorder history, offspring internalizing disorder history, family stressors, and school-related stressors on BPD risk. Contrary to expectations, no interactions between chronically stressful environmental conditions and personal characteristics in predicting borderline personality features were detected. Implications of these findings for etiological theories of BPD and early screening efforts are discussed.

  4. Socio-emotional skills, behavior problems, and Spanish competence predict the acquisition of English among English language learners in poverty.

    PubMed

    Winsler, Adam; Kim, Yoon Kyong; Richard, Erin R

    2014-09-01

    This article analyzes the role that individual differences in children's cognitive, Spanish competence, and socio-emotional and behavioral skills play in predicting the concurrent and longitudinal acquisition of English among a large sample of ethnically diverse, low-income, Hispanic preschool children. Participants assessed at age 4 for language, cognitive, socio-emotional, and behavioral skills were followed through kindergarten. Multivariate analyses demonstrated that Spanish-speaking preschoolers with greater initiative, self-control, and attachment and fewer behavior problems at age 4 were more successful in obtaining English proficiency by the end of kindergarten compared to those initially weaker in these skills, even after controlling for cognitive/language skills and demographic variables. Also, greater facility in Spanish at age 4 predicted the attainment of English proficiency. Social and behavioral skills and proficiency in Spanish are valuable resources for low-income English language learners during their transition to school.

  5. [A Longitudinal Study on Labour Market Transitions and Sustainability of Employment After Further Training Measures in the Context of Vocational Rehabilitation].

    PubMed

    Reims, Nancy; Tophoven, Silke

    2018-06-01

    The study examines employment prospects of persons who participate in further and re-training measures in the context of vocational rehabilitation in the responsibility of the Federal Employment Agency (FEA). Using administrative data of the FEA (RehaPro), we focus on persons completing vocational rehabilitation between 2009 and 2012 (N=21,772). We employ event history analysis to present time and extent of employment transition and their sustainability. By using multivariate analyses, factors for taking up employment are identified. Within 500 days, 70 % of promoted persons gain contributed employment, often directly after rehabilitation. The median for employment duration within the observation period is 670 days. Further training measures are an important opportunity for the re-integration of persons with health limitations in the labour market. © Georg Thieme Verlag KG Stuttgart · New York.

  6. The Time Course of Knee Swelling Post Total Knee Arthroplasty and Its Associations with Quadriceps Strength and Gait Speed.

    PubMed

    Pua, Yong-Hao

    2015-07-01

    This study examines the time course of knee swelling post total knee arthroplasty (TKA) and its associations with quadriceps strength and gait speed. Eighty-five patients with unilateral TKA participated. Preoperatively and on post-operative days (PODs) 1, 4, 14, and 90, knee swelling was measured using bioimpedance spectrometry. Preoperatively and on PODs 14 and 90, quadriceps strength was measured using isokinetic dynamometry while fast gait speed was measured using the timed 10-meter walk. On POD1, knee swelling increased ~35% from preoperative levels after which, knee swelling reduced but remained at ~11% above preoperative levels on POD90. In longitudinal, multivariable analyses, knee swelling was associated with quadriceps weakness (P<0.01) and slower gait speed (P=0.03). Interventions to reduce post-TKA knee swelling may be indicated to improve quadriceps strength and gait speed. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Exploring the Academic Benefits of Friendship Ties for Latino Boys and Girls*

    PubMed

    Riegle-Crumb, Catherine; Callahan, Rebecca M

    2009-09-01

    OBJECTIVES: We examine how the racial/ethnic and generational status composition of Latino students' friendship groups is related to their academic achievement and whether there are differential effects by gender. METHODS: We use multivariate regression analyses to examine the effects of friends' characteristics on Latino students' end of high school grades, utilizing data from the Adolescent Health and Academic Achievement Study (AHAA), and its parent survey, the National Longitudinal Study of Adolescent Health (Add Health). RESULTS: For Latina girls, there are positive effects of having more friendship ties to third-plus-generation Latino peers in contrast to dominant culture peers; yet Latino boys benefit academically from ties to all co-ethnic peers. Having friends with higher parental education promotes achievement of both genders. CONCLUSION: Our results counter notions of a pervasive negative peer influence of minority youth and suggest that co-ethnic ties are an important source of social capital for Latino students' achievement.

  8. Social Class, Family Formation, and Delinquency in Early Adulthood

    PubMed Central

    Kuhl, Danielle C.; Chavez, Jorge M.; Swisher, Raymond R.; Wilczak, Andrew

    2015-01-01

    Recent research suggests increasing heterogeneity in the transition from adolescence to early adulthood. This study considers how this heterogeneity may influence delinquency between these two developmental periods. We focus on the role of family transitions, educational attainment, and employment in predicting risk of nonviolent delinquency and substance use, as well as disparities in transitions across socioeconomic status subgroups. Data are from the National Longitudinal Study of Adolescent to Adult Health (Add Health). We find that family and neighborhood advantage are negatively associated with transitions into marriage, cohabitation, and parenthood, yet positively associated with educational attainment. In addition, adolescent family and neighborhood advantage are associated with a continuation of delinquent behavior and substance use during early adulthood. In multivariate analyses, accounting for family transitions in early adulthood largely attenuates the relationship between neighborhood advantage in adolescence and delinquency in early adulthood. We conclude by discussing the implications of our findings for developmental criminology. PMID:27418713

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

    PubMed

    Ferrara, Christine Therese; Geyer, Susan Michelle; Liu, Yuk-Fun; Evans-Molina, Carmella; Libman, Ingrid M; Besser, Rachel; Becker, Dorothy J; Rodriguez, Henry; Moran, Antoinette; Gitelman, Stephen E; Redondo, Maria J

    2017-05-01

    We aimed to determine the effect of elevated BMI over time on the progression to type 1 diabetes in youth. We studied 1,117 children in the TrialNet Pathway to Prevention cohort (autoantibody-positive relatives of patients with type 1 diabetes). Longitudinally accumulated BMI above the 85th age- and sex-adjusted percentile generated a cumulative excess BMI (ceBMI) index. Recursive partitioning and multivariate analyses yielded sex- and age-specific ceBMI thresholds for greatest type 1 diabetes risk. Higher ceBMI conferred significantly greater risk of progressing to type 1 diabetes. The increased diabetes risk occurred at lower ceBMI values in children <12 years of age compared with older subjects and in females versus males. Elevated BMI is associated with increased risk of diabetes progression in pediatric autoantibody-positive relatives, but the effect varies by sex and age. © 2017 by the American Diabetes Association.

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

    PubMed Central

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

    2017-01-01

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

  11. Residual Strength Pressure Tests and Nonlinear Analyses of Stringer- and Frame-Stiffened Aluminum Fuselage Panels with Longitudinal Cracks

    NASA Technical Reports Server (NTRS)

    Young, Richard D.; Rouse, Marshall; Ambur, Damodar R.; Starnes, James H., Jr.

    1999-01-01

    The results of residual strength pressure tests and nonlinear analyses of stringer- and frame-stiffened aluminum fuselage panels with longitudinal cracks are presented. Two types of damage are considered: a longitudinal crack located midway between stringers, and a longitudinal crack adjacent to a stringer and along a row of fasteners in a lap joint that has multiple-site damage (MSD). In both cases, the longitudinal crack is centered on a severed frame. The panels are subjected to internal pressure plus axial tension loads. The axial tension loads are equivalent to a bulkhead pressure load. Nonlinear elastic-plastic residual strength analyses of the fuselage panels are conducted using a finite element program and the crack-tip-opening-angle (CTOA) fracture criterion. Predicted crack growth and residual strength results from nonlinear analyses of the stiffened fuselage panels are compared with experimental measurements and observations. Both the test and analysis results indicate that the presence of MSD affects crack growth stability and reduces the residual strength of stiffened fuselage shells with long cracks.

  12. Residual Strength Pressure Tests and Nonlinear Analyses of Stringer-and Frame-Stiffened Aluminum Fuselage Panels with Longitudinal Cracks

    NASA Technical Reports Server (NTRS)

    Young, Richard D.; Rouse, Marshall; Ambur, Damodar R.; Starnes, James H., Jr.

    1998-01-01

    The results of residual strength pressure tests and nonlinear analyses of stringer- and frame-stiffened aluminum fuselage panels with longitudinal cracks are presented. Two types of damage are considered: a longitudinal crack located midway between stringers, and a longitudinal crack adjacent to a stringer and along a row of fasteners in a lap joint that has multiple-site damage (MSD). In both cases, the longitudinal crack is centered on a severed frame. The panels are subjected to internal pressure plus axial tension loads. The axial tension loads are equivalent to a bulkhead pressure load. Nonlinear elastic-plastic residual strength analyses of the fuselage panels are conducted using a finite element program and the crack-tip-opening-angle (CTOA) fracture criterion. Predicted crack growth and residual strength results from nonlinear analyses of the stiffened fuselage panels are compared with experimental measurements and observations. Both the test and analysis results indicate that the presence of MSD affects crack growth stability and reduces the residual strength of stiffened fuselage shells with long cracks.

  13. Evaluating the Impact of CETA on Participant Earnings.

    ERIC Educational Resources Information Center

    Bryant, Edward C.; Rupp, Kalman

    1987-01-01

    Estimates of the Comprehensive Employment and Training Act's net impact on participant earnings, using Continuous Longitudinal Manpower Survey data, were compared to a similar sample from the Current Population Survey. The use of multivariate matching and weighting yielded acceptable results. (GDC)

  14. Associations between substance use, post-traumatic stress disorder and the perpetration of violence: A longitudinal investigation.

    PubMed

    Barrett, Emma L; Teesson, Maree; Mills, Katherine L

    2014-06-01

    Substance use disorder (SUD) and post-traumatic stress disorder (PTSD) commonly co-occur. This is of significant concern, given the increased risk for violence perpetration among individuals with this comorbidity. Limited research, however, has examined relationships between SUD, PTSD and violence among individuals longitudinally. Such an investigation is warranted given that substance use and PTSD symptoms can fluctuate over time. This study therefore aims to examine how changes in substance use and PTSD symptom severity are associated with the perpetration of violent crime over time among individuals with comorbid SUD and PTSD. One-hundred and two men and women who met criteria for SUD and PTSD were interviewed four times over a 9-month period. These interviews included measures of past-month violent crime perpetration, substance use and dependence, PTSD symptom severity, and depression and state anxiety symptoms. Generalised estimating equations (GEE) modelled associations between substance use, PTSD and violence. Increased substance use, more severe substance dependence and more severe PTSD symptomology were consistently associated with violent crime over time. Multivariate GEE analyses, however, revealed that the PTSD hyperarousal symptoms, specifically, were independently associated with violence over time. This longitudinal study found that PTSD hyperarousal symptoms were consistently associated with the perpetration of violent crime, further highlighting the potentiating role of PTSD hyperarousal in relation to violence among individuals with SUD. These findings indicate that interventions addressing hyperarousal symptoms have the potential to reduce the susceptibility for violence among individuals with this common comorbidity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Longitudinal Trajectories and Associated Baseline Predictors in Youths With Bipolar Spectrum Disorders

    PubMed Central

    Birmaher, Boris; Gill, Mary Kay; Axelson, David A.; Goldstein, Benjamin I.; Goldstein, Tina R.; Yu, Haifeng; Liao, Fangzi; Iyengar, Satish; Diler, Rasim S.; Strober, Michael; Hower, Heather; Yen, Shirley; Hunt, Jeffrey; Merranko, John A.; Ryan, Neal D.; Keller, Martin B.

    2014-01-01

    Objective The authors sought to identify and evaluate longitudinal mood trajectories and associated baseline predictors in youths with bipolar disorder. Method A total of 367 outpatient youths (mean age, 12.6 years) with bipolar disorder with at least 4 years of follow-up were included. After intake, participants were interviewed on average 10 times (SD=3.2) over a mean of 93 months (SD=8.3). Youths and parents were interviewed for psychopathology, functioning, treatment, and familial psychopathology and functioning. Results Latent class growth analysis showed four different longitudinal mood trajectories: “predominantly euthymic” (24.0%), “moderately euthymic” (34.6%), “ill with improving course” (19.1%), and “predominantly ill” (22.3%). Within each class, youths were euthymic on average 84.4%, 47.3%, 42.8%, and 11.5% of the follow-up time, respectively. Multivariate analyses showed that better course was associated with higher age at onset of mood symptoms, less lifetime family history of bipolar disorder and substance abuse, and less history at baseline of severe depression, manic symptoms, suicidality, subsyndromal mood episodes, and sexual abuse. Most of these factors were more noticeable in the “predominantly euthymic” class. The effects of age at onset were attenuated in youths with lower socioeconomic status, and the effects of depression severity were absent in those with the highest socioeconomic status. Conclusions A substantial proportion of youths with bipolar disorder, especially those with adolescent onset and the above-noted factors, appear to be euthymic over extended periods. Nonetheless, continued syndromal and subsyndromal mood symptoms in all four classes underscore the need to optimize treatment. PMID:24874203

  16. Project YOURLIFE (What Young People Think and Feel about Relationships, Love, Sexuality, and Related Risk Behavior): Cross-sectional and Longitudinal Protocol.

    PubMed

    Carlos, Silvia; Osorio, Alfonso; Calatrava, María; Lopez-Del Burgo, Cristina; Ruiz-Canela, Miguel; de Irala, Jokin

    2016-01-01

    Sexually transmitted infections and unplanned pregnancies affect adolescent sexual health and are serious public health concerns. They result from sexual intercourse in adolescence, which is usually associated with multiple partners, unprotected sex, and condom misuse. This behavior is related to socio-ecological factors that influence lifestyles. The YOURLIFE project aims to find out what young people think and feel about relationships, love, and sexuality, and to assess the associations between these thoughts and attitudes, adolescents' social factors, and sexual health. An international school-based study with a cross-sectional and optional subsequent longitudinal design. Three online questionnaires designed for adolescents aged 13/14, 15/16, and 17/18, respectively, will be used. A matching coding system will allow longitudinal follow-up when adolescents reply to follow-up surveys. Questionnaires will include questions related to sociodemographic data; information/communication technologies; leisure time; parental supervision; influences of parents/friends; information sources; messages perceived; and sexuality-related knowledge, attitudes, and opinions. The second and third questionnaires for participants aged 15/16 and 17/18 will also contain variables concerning sexual behavior. Schools will be able to use their results to tailor educational approaches targeting the needs of their students. Multivariate analyses will be performed using the larger international dataset. The YOURLIFE project will collect comprehensive information about the socio-ecological determinants of the sexual risk-taking of schooled adolescents worldwide. Effective preventive programs could be subsequently designed and tailored to the specific determinants of adolescents from different schools and settings, and also, when analyzed globally, to public health professionals.

  17. Risk factors for intimate partner violence in women in the Rakai Community Cohort Study, Uganda, from 2000 to 2009

    PubMed Central

    2013-01-01

    Background Intimate partner violence (IPV) is a significant public health problem. There is a lack of data on IPV risk factors from longitudinal studies and from low and middle income countries. Identifying risk factors is needed to inform the design of appropriate IPV interventions. Methods Data were from the Rakai Community Cohort Study annual surveys between 2000 and 2009. Female participants who had at least one sexual partner during this period and had data on IPV over the study period were included in analyses (N = 15081). Factors from childhood and early adulthood as well as contemporary factors were considered in separate models. Logistic regression was used to assess early risk factors for IPV during the study period. Longitudinal data analysis was used to assess contemporary risk factors in the past year for IPV in the current year, using a population-averaged multivariable logistic regression model. Results Risk factors for IPV from childhood and early adulthood included sexual abuse in childhood or adolescence, earlier age at first sex, lower levels of education, and forced first sex. Contemporary risk factors included younger age, being married, relationships of shorter duration, having a partner who is the same age or younger, alcohol use before sex by women and by their partners, and thinking that violence is acceptable. HIV infection and pregnancy were not associated with an increased odds of IPV. Conclusions Using longitudinal data, this study identified a number of risk factors for IPV. These findings are useful for the development of prevention strategies to prevent and mitigate IPV in women. PMID:23759123

  18. Factors promoting health-related quality of life in people with rheumatic diseases: a 12 month longitudinal study

    PubMed Central

    2011-01-01

    Background Rheumatic diseases have a significant adverse impact on the individual from physical, mental and social aspects, resulting in a low health-related quality of life (HRQL). There is a lack of longitudinal studies on HRQL in people with rheumatic diseases that focus on factors promoting HRQL instead of risk factors. The aim of this study was to investigate the associations between suggested health promoting factors at baseline and outcome in HRQL at a 12 month follow-up in people with rheumatic diseases. Methods A longitudinal cohort study was conducted in 185 individuals with rheumatic diseases with questionnaires one week and 12 months after rehabilitation in a Swedish rheumatology clinic. HRQL was assessed by SF-36 together with suggested health factors. The associations between SF-36 subscales and the health factors were analysed by multivariable logistic regressions. Results Factors predicting better outcome in HRQL in one or several SF-36 subscales were being younger or middle-aged, feeling painless, having good sleep structure, feeling rested after sleep, performing low effort of exercise more than twice per week, having strong sense of coherence (SOC), emotional support and practical assistance, higher educational level and work capacity. The most important factors were having strong SOC, feeling rested after sleep, having work capacity, being younger or middle-aged, and having good sleep structure. Conclusions This study identified several factors that promoted a good outcome in HRQL to people with rheumatic diseases. These health factors could be important to address in clinical work with rheumatic diseases in order to optimise treatment strategies. PMID:21599884

  19. Longitudinal and Cross-Sectional Analyses of Visual Field Progression in Participants of the Ocular Hypertension Treatment Study (OHTS)

    PubMed Central

    Chauhan, Balwantray C; Keltner, John L; Cello, Kim E; Johnson, Chris A; Anderson, Douglas R; Gordon, Mae O; Kass, Michael A

    2014-01-01

    Purpose Visual field progression can be determined by evaluating the visual field by serial examinations (longitudinal analysis), or by a change in classification derived from comparison to age-matched normal data in single examinations (cross-sectional analysis). We determined the agreement between these two approaches in data from the Ocular Hypertension Treatment Study (OHTS). Methods Visual field data from 3088 eyes of 1570 OHTS participants (median follow-up 7 yrs, 15 tests with static automated perimetry) were analysed. Longitudinal analyses were performed with change probability with total and pattern deviation, and cross-sectional analysis with Glaucoma Hemifield Test, Corrected Pattern Standard Deviation, and Mean Deviation. The rates of Mean Deviation and General Height change were compared to estimate the degree of diffuse loss in emerging glaucoma. Results The agreement on progression in longitudinal and cross-sectional analyses ranged from 50% to 61% and remained nearly constant across a wide range of criteria. In contrast, the agreement on absence of progression ranged from 97% to 99.7%, being highest for the stricter criteria. Analyses of pattern deviation were more conservative than total deviation, with a 3 to 5 times lesser incidence of progression. Most participants developing field loss had both diffuse and focal change. Conclusions Despite considerable overall agreement, between 40 to 50% of eyes identified as having progressed with either longitudinal or cross-sectional analyses were identified with only one of the analyses. Because diffuse change is part of early glaucomatous damage, pattern deviation analyses may underestimate progression in patients with ocular hypertension. PMID:21149774

  20. Late Fecal Incontinence After High-Dose Radiotherapy for Prostate Cancer: Better Prediction Using Longitudinal Definitions

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

    Fiorino, Claudio, E-mail: fiorino.claudio@hsr.it; Rancati, Tiziana; Fellin, Gianni

    2012-05-01

    Purpose: To model late fecal incontinence after high-dose prostate cancer radiotherapy (RT) in patients accrued in the AIROPROS (prostate working group of the Italian Association of Radiation Oncology) 0102 trial using different endpoint definitions. Methods and Materials: The self-reported questionnaires (before RT, 1 month after RT, and every 6 months for {<=}3 years after RT) of 586 patients were available. The peak incontinence (P{sub I}NC) and two longitudinal definitions (chronic incontinence [C{sub I}NC], defined as the persistence of Grade 1 or greater incontinence after any Grade 2-3 event; and mean incontinence score [M{sub I}NC], defined as the average score duringmore » the 3-year period after RT) were considered. The correlation between the clinical/dosimetric parameters (including rectal dose-volume histograms) and P{sub I}NC (Grade 2 or greater), C{sub I}NC, and M{sub I}NC of {>=}1 were investigated using multivariate logistic analyses. Receiver operating characteristic curves and the area under the curve were used to assess the predictive value of the different multivariate models. Results: Of the 586 patients, 36 with a Grade 1 or greater incontinence score before RT were not included in the present analysis. Of the 550 included patients, 197 (35.8%) had at least one control with a Grade 1 or greater incontinence score (M{sub I}NC >0). Of these 197 patients, 37 (6.7%), 22 (4.0%), and 17 (3.1%) were scored as having P{sub I}NC, M{sub I}NC {>=}1, and C{sub I}NC, respectively. On multivariate analysis, Grade 2 or greater acute incontinence was the only predictor of P{sub I}NC (odds ratio [OR], 5.9; p = .0009). Grade 3 acute incontinence was predictive of C{sub I}NC (OR, 9.4; p = .02), and percentage of the rectal volume receiving >40 Gy of {>=}80% was predictive of a M{sub I}NC of {>=}1 (OR, 3.8; p = .008) and of C{sub I}NC (OR, 3.6; p = .03). Previous bowel disease, previous abdominal/pelvic surgery, and the use of antihypertensive (protective factor) correlated highly with both C{sub I}NC and M{sub I}NC {>=}1. The predictive values of the models for C{sub I}NC (area under the curve, 0.83) and M{sub I}NC {>=}1 (area under the curve, 0.73) were greater than the ones for P{sub I}NC (area under the curve, 0.62) and more reliable (p = .0001-.0003 against p = .02). Nomograms for the two longitudinal definitions were derived. Conclusions: The longitudinal definitions of fecal incontinence (C{sub I}NC and M{sub I}NC {>=}1) were helpful in accounting for both the persistence and the severity of the incontinence. A significant fraction of peak events was consequential to acute incontinence, and a longer duration of symptoms mainly depended on the rectal dose bath (percentage of rectal volume receiving >40 Gy), and pretreatment clinical factors.« less

  1. Influence of parental factors on adolescents' transition to first sexual intercourse in Nairobi, Kenya: a longitudinal study.

    PubMed

    Okigbo, Chinelo C; Kabiru, Caroline W; Mumah, Joyce N; Mojola, Sanyu A; Beguy, Donatien

    2015-08-21

    Several studies have demonstrated a link between young people's sexual behavior and levels of parental monitoring, parent-child communication, and parental discipline in Western countries. However, little is known about this association in African settings, especially among young people living in high poverty settings such as urban slums. The objective of the study was to assess the influence of parental factors (monitoring, communication, and discipline) on the transition to first sexual intercourse among unmarried adolescents living in urban slums in Kenya. Longitudinal data collected from young people living in two slums in Nairobi, Kenya were used. The sample was restricted to unmarried adolescents aged 12-19 years at Wave 1 (weighted n = 1927). Parental factors at Wave 1 were used to predict adolescents' transition to first sexual intercourse by Wave 2. Relevant covariates including the adolescents' age, sex, residence, school enrollment, religiosity, delinquency, and peer models for risk behavior were controlled for. Multivariate logistic regression models were used to assess the associations of interest. All analyses were conducted using Stata version 13. Approximately 6% of our sample transitioned to first sexual intercourse within the one-year study period; there was no sex difference in the transition rate. In the multivariate analyses, male adolescents who reported communication with their mothers were less likely to transition to first sexual intercourse compared to those who did not (p < 0.05). This association persisted even after controlling for relevant covariates (OR: ≤0.33; p < 0.05). However, parental monitoring, discipline, and communication with their fathers did not predict transition to first sexual intercourse for male adolescents. For female adolescents, parental monitoring, discipline, and communication with fathers predicted transition to first sexual intercourse; however, only communication with fathers remained statistically significant after controlling for relevant covariates (OR: 0.30; 95% C.I.: 0.13-0.68). This study provides evidence that cross-gender communication with parents is associated with a delay in the onset of sexual intercourse among slum-dwelling adolescents. Targeted adolescent sexual and reproductive health programmatic interventions that include parents may have significant impacts on delaying sexual debut, and possibly reducing sexual risk behaviors, among young people in high-risk settings such as slums.

  2. Circulating CD4+CD28null and extra-thymic CD4+CD8+ double positive T cells are independently associated with disease damage in systemic lupus erythematosus patients.

    PubMed

    Ugarte-Gil, M F; Sánchez-Zúñiga, C; Gamboa-Cárdenas, R V; Aliaga-Zamudio, M; Zevallos, F; Tineo-Pozo, G; Cucho-Venegas, J M; Mosqueira-Riveros, A; Medina, M; Perich-Campos, R A; Alfaro-Lozano, J L; Rodriguez-Bellido, Z; Alarcón, G S; Pastor-Asurza, C A

    2016-03-01

    To determine whether circulating CD4+CD28null and extra-thymic CD4+CD8+ double positive (DP) T cells are independently associated with damage accrual in systemic lupus erythematosus (SLE) patients. This cross-sectional study was conducted between September 2013 and April 2014 in consecutive SLE patients from our Rheumatology Department. CD4+CD28null and CD4+CD8+ DP T-cell frequencies were analyzed by flow-cytometry. The association of damage (SLICC/ACR Damage Index, SDI) and CD4+CD28null and CD4+CD8+ DP T cells was examined by univariable and multivariable Poisson regression models, adjusting for possible confounders. All analyses were performed using SPSS 21.0. Patients' (n = 133) mean (SD) age at diagnosis was 35.5 (16.8) years, 124 (93.2%) were female; all were mestizo (mixed Caucasian and Amerindian ancestry). Disease duration was 7.4 (6.8) years. The SLE Disease Activity Index was 5.5 (4.2), and the SDI 0.9 (1.2). The percentages of CD4+CD28null and CD4+CD8+ DP T cells were 17.1 (14.4) and 0.4 (1.4), respectively. The percentage of CD4+CD28null and CD4+CD8+ DP T cells were positively associated with a higher SDI in both univariable (rate ratio (RR) 1.02, 95% confidence interval (CI): 1.01-1.03 and 1.17, 95% CI: 1.07-1.27, respectively; p < 0.001 for both) and multivariable analyses RR 1.02, 95% CI: 1.01-1.03, p = 0.001 for CD4+CD28null T cells and 1.28, 95% CI: 1.13-1.44, p < 0.001 for CD4+CD8+ DP T cells). Only the renal domain remained associated with CD4+CD28null in multivariable analyses (RR 1.023 (1.002-1.045); p = 0.034). In SLE patients, CD4+CD28null and CD4+CD8+ DP T cells are independently associated with disease damage. Longitudinal studies are warranted to determine the predictive value of these associations. © The Author(s) 2015.

  3. The contribution of early language development to children's emotional and behavioural functioning at 6 years: an analysis of data from the Children in Focus sample from the ALSPAC birth cohort.

    PubMed

    Clegg, Judy; Law, James; Rush, Robert; Peters, Tim J; Roulstone, Susan

    2015-01-01

    An association between children's early language development and their emotional and behavioural functioning is reported in the literature. The nature of the association remains unclear and it has not been established if such an association is found in a population-based cohort in addition to clinical populations. This study examines the reported association between language development and emotional and behavioural functioning in a population-based cohort. Data from 1,314 children in the Children in Focus (CiF) sample from the Avon Longitudinal Study of Parents and Children (ALSPAC) were analysed. Regression models identified the extent to which early language ability at 2 years of age and later language ability at 4 years of age is associated with emotional and behavioural functioning at 6 years while accounting for biological and social risk and adjusting for age and performance intelligence (PIQ). A series of univariable and multivariable analyses identified a strong influence of biological risk, social risk and early and later language ability to emotional and behavioural functioning. Interestingly, social risk dropped out of the multivariate analyses when age and PIQ were controlled for. Early expressive vocabulary at 2 years and receptive language at 4 years made a strong contribution to emotional and behavioural functioning at 6 years in addition to biological risk. The final model accounted for 11.6% of the variance in emotional and behavioural functioning at 6 years. The study identified that early language ability at 2 years, specifically expressive vocabulary and later receptive language at 4 years both made a moderate, but important contribution to emotional and behavioural functioning at 6 years of age. Although children's language development is important in understanding children's emotional and behavioural functioning, the study shows that it is one of many developmental factors involved. © 2014 The Authors. Journal of Child Psychology and Psychiatry. © 2014 Association for Child and Adolescent Mental Health.

  4. Impact of co-morbidities and patient characteristics on international normalized ratio control over time in patients with nonvalvular atrial fibrillation.

    PubMed

    Nelson, Winnie W; Choi, Jiyoon C; Vanderpoel, Julie; Damaraju, Chandrasekharra V; Wildgoose, Peter; Fields, Larry E; Schein, Jeffrey R

    2013-08-15

    This study determined the association between co-morbidities, including heart failure (HF) and time in therapeutic range (TTR), in patients with nonvalvular atrial fibrillation. Longitudinal patient-level anticoagulation management records collected from 2006 to 2010 were analyzed. Adult patients with nonvalvular atrial fibrillation who used warfarin for a 12-month period with no gap of >60 days between visits were identified. TTR <55% was defined as "lower" TTR. CHADS₂ score of ≥2 was defined as "higher" CHADS₂. Logistic regression analyses were conducted to determine the association between co-morbidities and TTR. A total of 23,425 patients met the study criteria. The mean age ± SD was 74.8 ± 9.7 years, with 84.8% aged ≥65 years. The most common co-morbidities were hypertension (41.7%), diabetes (24.1%), HF (11.7%), and previous stroke (11.1%). The mean TTR ± SD was 67.3 ± 14.4%, with 18.6% of patients in the lower TTR range. In multivariate analyses using age, gender, hypertension, diabetes, stroke, and region as covariates, HF (adjusted odds ratio [OR] 1.41, 95% confidence interval [CI] 1.28 to 1.56; p <0.001), diabetes (OR 1.28, 95% CI 1.19 to 1.38; p <0.001), and previous stroke (OR 1.15, 95% CI 1.04 to 1.27; p <0.001) were associated with lower TTR. In a second set of multivariate analyses using gender and region as covariates, a higher CHADS₂ score was associated with lower TTR (OR 1.11, 95% CI 1.04 to 1.18; p <0.001). In conclusion, HF was associated with the greatest likelihood of a lower TTR, followed by diabetes, then stroke. Anticoagulation control may be more challenging for patients with these conditions. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Using empirical Bayes predictors from generalized linear mixed models to test and visualize associations among longitudinal outcomes.

    PubMed

    Mikulich-Gilbertson, Susan K; Wagner, Brandie D; Grunwald, Gary K; Riggs, Paula D; Zerbe, Gary O

    2018-01-01

    Medical research is often designed to investigate changes in a collection of response variables that are measured repeatedly on the same subjects. The multivariate generalized linear mixed model (MGLMM) can be used to evaluate random coefficient associations (e.g. simple correlations, partial regression coefficients) among outcomes that may be non-normal and differently distributed by specifying a multivariate normal distribution for their random effects and then evaluating the latent relationship between them. Empirical Bayes predictors are readily available for each subject from any mixed model and are observable and hence, plotable. Here, we evaluate whether second-stage association analyses of empirical Bayes predictors from a MGLMM, provide a good approximation and visual representation of these latent association analyses using medical examples and simulations. Additionally, we compare these results with association analyses of empirical Bayes predictors generated from separate mixed models for each outcome, a procedure that could circumvent computational problems that arise when the dimension of the joint covariance matrix of random effects is large and prohibits estimation of latent associations. As has been shown in other analytic contexts, the p-values for all second-stage coefficients that were determined by naively assuming normality of empirical Bayes predictors provide a good approximation to p-values determined via permutation analysis. Analyzing outcomes that are interrelated with separate models in the first stage and then associating the resulting empirical Bayes predictors in a second stage results in different mean and covariance parameter estimates from the maximum likelihood estimates generated by a MGLMM. The potential for erroneous inference from using results from these separate models increases as the magnitude of the association among the outcomes increases. Thus if computable, scatterplots of the conditionally independent empirical Bayes predictors from a MGLMM are always preferable to scatterplots of empirical Bayes predictors generated by separate models, unless the true association between outcomes is zero.

  6. The Decoding Toolbox (TDT): a versatile software package for multivariate analyses of functional imaging data

    PubMed Central

    Hebart, Martin N.; Görgen, Kai; Haynes, John-Dylan

    2015-01-01

    The multivariate analysis of brain signals has recently sparked a great amount of interest, yet accessible and versatile tools to carry out decoding analyses are scarce. Here we introduce The Decoding Toolbox (TDT) which represents a user-friendly, powerful and flexible package for multivariate analysis of functional brain imaging data. TDT is written in Matlab and equipped with an interface to the widely used brain data analysis package SPM. The toolbox allows running fast whole-brain analyses, region-of-interest analyses and searchlight analyses, using machine learning classifiers, pattern correlation analysis, or representational similarity analysis. It offers automatic creation and visualization of diverse cross-validation schemes, feature scaling, nested parameter selection, a variety of feature selection methods, multiclass capabilities, and pattern reconstruction from classifier weights. While basic users can implement a generic analysis in one line of code, advanced users can extend the toolbox to their needs or exploit the structure to combine it with external high-performance classification toolboxes. The toolbox comes with an example data set which can be used to try out the various analysis methods. Taken together, TDT offers a promising option for researchers who want to employ multivariate analyses of brain activity patterns. PMID:25610393

  7. Scalable Joint Models for Reliable Uncertainty-Aware Event Prediction.

    PubMed

    Soleimani, Hossein; Hensman, James; Saria, Suchi

    2017-08-21

    Missing data and noisy observations pose significant challenges for reliably predicting events from irregularly sampled multivariate time series (longitudinal) data. Imputation methods, which are typically used for completing the data prior to event prediction, lack a principled mechanism to account for the uncertainty due to missingness. Alternatively, state-of-the-art joint modeling techniques can be used for jointly modeling the longitudinal and event data and compute event probabilities conditioned on the longitudinal observations. These approaches, however, make strong parametric assumptions and do not easily scale to multivariate signals with many observations. Our proposed approach consists of several key innovations. First, we develop a flexible and scalable joint model based upon sparse multiple-output Gaussian processes. Unlike state-of-the-art joint models, the proposed model can explain highly challenging structure including non-Gaussian noise while scaling to large data. Second, we derive an optimal policy for predicting events using the distribution of the event occurrence estimated by the joint model. The derived policy trades-off the cost of a delayed detection versus incorrect assessments and abstains from making decisions when the estimated event probability does not satisfy the derived confidence criteria. Experiments on a large dataset show that the proposed framework significantly outperforms state-of-the-art techniques in event prediction.

  8. Poor working conditions and work stress among Canadian sex workers.

    PubMed

    Duff, P; Sou, J; Chapman, J; Dobrer, S; Braschel, M; Goldenberg, S; Shannon, K

    2017-10-01

    While sex work is often considered the world's oldest profession, there remains a dearth of research on work stress among sex workers (SWs) in occupational health epidemiological literature. A better understanding of the drivers of work stress among SWs is needed to inform sex work policy, workplace models and standards. To examine the factors that influence work stress among SWs in Metro Vancouver. Analyses drew from a longitudinal cohort of SWs, known as An Evaluation of Sex Workers' Health Access (AESHA) (2010-14). A modified standardized 'work stress' scale, multivariable linear regression with generalized estimating equations was used to longitudinally examine the factors associated with work stress. In multivariable analysis, poor working conditions were associated with increased work stress and included workplace physical/sexual violence (β = 0.18; 95% confidence interval (CI) 0.06, 0.29), displacement due to police (β = 0.26; 95% CI 0.14, 0.38), working in public spaces (β = 0.73; 95% CI 0.61, 0.84). Older (β = -0.02; 95% CI -0.03, -0.01) and Indigenous SWs experienced lower work stress (β = -0.25; 95% CI -0.43, -0.08), whereas non-injection (β = 0.32; 95% CI 0.14, 0.49) and injection drug users (β = 0.17; 95% CI 0.03, 0.31) had higher work stress. Vancouver-based SWs' work stress was largely shaped by poor work conditions, such as violence, policing, lack of safe workspaces. There is a need to move away from criminalized approaches which shape unsafe work conditions and increase work stress for SWs. Policies that promote SWs' access to the same occupational health, safety and human rights standards as workers in other labour sectors are also needed. © The Author 2017. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  9. How Do We Match Instructional Effectiveness with Learning Curves?

    ERIC Educational Resources Information Center

    Branum-Martin, Lee; Mehta, Paras D.; Taylor, W. Patrick; Carlson, Coleen D.; Lei, Xiaoxuan; Hunter, C. Vincent; Francis, David J.

    2015-01-01

    In order to examine the effectiveness of instruction, the authors confront formidable statistical problems, including multivariate structure of classroom observations, longitudinal dependence of both classroom observations and student outcomes. As the authors begin to examine instruction, classroom observations involve multiple variables for which…

  10. Cancer and heart attack survivors' expectations of employment status: results from the English Longitudinal Study of Ageing.

    PubMed

    Duijts, Saskia F A; van der Beek, Allard J; Bleiker, Eveline M A; Smith, Lee; Wardle, Jane

    2017-08-07

    Sociodemographic, health- and work-related factors have been found to influence return to work in cancer survivors. It is feasible though that behavioural factors, such as expectation of being at work, could also affect work-related outcomes. Therefore, the effect of earlier identified factors and expectation of being at work on future employment status in cancer survivors was explored. To assess the degree to which these factors specifically concern cancer survivors, a comparison with heart attack survivors was made. Data from the English Longitudinal Study of Ageing were used. Cancer and heart attack survivors of working age in the UK were included and followed up for 2 years. Baseline characteristics of both cancer and heart attack survivors were compared regarding employment status. Univariate and multivariate regression analyses were performed in survivors at work, and the interaction between independent variables and diagnose group was assessed. In cancer survivors at work (N = 159), alcohol consumption, participating in moderate or vigorous sport activities, general health and participation were univariate associated with employment status at two-year follow-up. Only fair general health (compared to very good general health) remained statistically significant in the multivariate model (OR 0.31; 95% CI 0.13-0.76; p = 0.010). In heart attack survivors at work (N = 78), gender, general health and expectation of being at work were univariate associated with employment status at follow-up. Female gender (OR 0.03; 95% CI 0.00-0.57; p = 0.018) and high expectation of being at work (OR 10.68; 95% CI 1.23-93.92; p = 0.033) remained significant in the multivariate model. The influence of gender (p = 0.066) and general health (p = 0.020) regarding employment status was found to differ significantly between cancer and heart attack survivors. When predicting future employment status in cancer survivors in the UK, general health is the most relevant factor to consider. While expectation of being at work did not show any significant influence in cancer survivors, in heart attack survivors, it should not be disregarded though, when developing interventions to affect their employment status. Future research should focus on more specific measures for expectation, and additional behavioural factors, such as self-efficacy, and their effect on employment status.

  11. On Models for Binomial Data with Random Numbers of Trials

    PubMed Central

    Comulada, W. Scott; Weiss, Robert E.

    2010-01-01

    Summary A binomial outcome is a count s of the number of successes out of the total number of independent trials n = s + f, where f is a count of the failures. The n are random variables not fixed by design in many studies. Joint modeling of (s, f) can provide additional insight into the science and into the probability π of success that cannot be directly incorporated by the logistic regression model. Observations where n = 0 are excluded from the binomial analysis yet may be important to understanding how π is influenced by covariates. Correlation between s and f may exist and be of direct interest. We propose Bayesian multivariate Poisson models for the bivariate response (s, f), correlated through random effects. We extend our models to the analysis of longitudinal and multivariate longitudinal binomial outcomes. Our methodology was motivated by two disparate examples, one from teratology and one from an HIV tertiary intervention study. PMID:17688514

  12. Activation and Self-Efficacy in a Randomized Trial of a Depression Self-Care Intervention.

    PubMed

    McCusker, Jane; Lambert, Sylvie D; Cole, Martin G; Ciampi, Antonio; Strumpf, Erin; Freeman, Ellen E; Belzile, Eric

    2016-12-01

    In a sample of primary care participants with chronic physical conditions and comorbid depressive symptoms: to describe the cross-sectional and longitudinal associations of activation and self-efficacy with demographic, physical and mental health status, health behaviors, depression self-care, health care utilization, and use of self-care tools; and to examine the effects of a depression self-care coaching intervention on these two outcomes. Design/Study Setting. A secondary analysis of activation and self-efficacy data collected as part of a randomized trial to compare the effects of a telephone-based coached depression self-care intervention with a noncoached intervention. Activation (Patient Activation Measure) was measured at baseline and 6 months. Depression self-care self-efficacy was assessed at baseline, at 3 months, and at 6 months. In multivariable cross-sectional analyses (n = 215), activation and/or self-efficacy were associated with language, birthplace, better physical and mental health, individual exercise, specialist visits, and antidepressant nonuse. In longitudinal analyses (n = 158), an increase in activation was associated with increased medication adherence; an increase in self-efficacy was associated with use of cognitive self-care strategies and increases in social and solitary activities. There were significant improvements from baseline to 6 months in activation and self-efficacy scores both among coached and noncoached groups. The self-care coaching intervention did not affect 6-month activation or self-efficacy but was associated with quicker improvement in self-efficacy. Overall, the results for activation and self-efficacy were similar, although self-efficacy correlated more consistently than activation with depression-specific behaviors and was responsive to a depression self-care coaching intervention. © 2016 Society for Public Health Education.

  13. Increased Airway Wall Thickness is Associated with Adverse Longitudinal First-Second Forced Expiratory Volume Trajectories of Former World Trade Center workers.

    PubMed

    de la Hoz, Rafael E; Liu, Xiaoyu; Doucette, John T; Reeves, Anthony P; Bienenfeld, Laura A; Wisnivesky, Juan P; Celedón, Juan C; Lynch, David A; San José Estépar, Raúl

    2018-05-24

    Occupational exposures at the WTC site after September 11, 2001 have been associated with several presumably inflammatory lower airway diseases. In this study, we describe the trajectories of expiratory air flow decline, identify subgroups with adverse progression, and investigate the association of a quantitative computed tomography (QCT) imaging measurement of airway wall thickness, and other risk factors for adverse progression. We examined the trajectories of expiratory air flow decline in a group of 799 former WTC workers and volunteers with QCT-measured (with two independent systems) wall area percent (WAP) and at least 3 periodic spirometries. We calculated individual regression lines for first-second forced expiratory volume (FEV 1 ), identified subjects with rapidly declining and increasing ("gainers"), and compared them to subjects with normal and "stable" FEV 1 decline. We used multivariate logistic regression to model decliner vs. stable trajectories. The mean longitudinal FEV 1 slopes for the entire study population, and its stable, decliner, and gainer subgroups were, respectively, - 35.8, - 8, - 157.6, and + 173.62 ml/year. WAP was associated with "decliner" status (OR adj 1.08, 95% CI 1.02, 1.14, per 5% increment) compared to stable. Age, weight gain, baseline FEV 1 percent predicted, bronchodilator response, and pre-WTC occupational exposures were also significantly associated with accelerated FEV 1 decline. Analyses of gainers vs. stable subgroup showed WAP as a significant predictor in unadjusted but not consistently in adjusted analyses. The apparent normal age-related rate of FEV 1 decline results from averaging widely divergent trajectories. WAP is significantly associated with accelerated air flow decline in WTC workers.

  14. Umbilical cord PUFA are determined by maternal and child fatty acid desaturase (FADS) genetic variants in the Avon Longitudinal Study of Parents and Children (ALSPAC)

    PubMed Central

    Lattka, Eva; Koletzko, Berthold; Zeilinger, Sonja; Hibbeln, Joseph R.; Klopp, Norman; Ring, Susan M.; Steer, Colin D.

    2012-01-01

    Fetal supply with long-chain PUFA (LC-PUFA) during pregnancy is important for brain growth and visual and cognitive development and is provided by materno–fetal placental transfer. We recently showed that maternal fatty acid desaturase (FADS) genotypes modulate the amounts of LC-PUFA in maternal blood. Whether FADS genotypes influence the amounts of umbilical cord fatty acids has not been investigated until now. The aim of the present study was to investigate the influence of maternal and child FADS genotypes on the amounts of LC-PUFA in umbilical cord venous plasma as an indicator of fetal fatty acid supply during pregnancy. A total of eleven cord plasma n-6 and n-3 fatty acids were analysed for association with seventeen FADS gene cluster SNP in over 2000 mothers and children from the Avon Longitudinal Study of Parents and Children. In a multivariable analysis, the maternal genotype effect was adjusted for the child genotype and vice versa to estimate which of the two has the stronger influence on cord plasma fatty acids. Both maternal and child FADS genotypes and haplotypes influenced amounts of cord plasma LC-PUFA and fatty acid ratios. Specifically, most analysed maternal SNP were associated with cord plasma levels of the precursor n-6 PUFA, whereas the child genotypes were mainly associated with more highly desaturated n-6 LC-PUFA. This first study on FADS genotypes and cord fatty acids suggests that fetal LC-PUFA status is determined to some extent by fetal fatty acid conversion. Associations of particular haplotypes suggest specific effects of SNP rs498793 and rs968567 on fatty acid metabolism. PMID:22877655

  15. C-reactive protein in atherosclerosis - A risk marker but not a causal factor? A 13-year population-based longitudinal study: The Tromsø study.

    PubMed

    Eltoft, Agnethe; Arntzen, Kjell Arne; Hansen, John-Bjarne; Wilsgaard, Tom; Mathiesen, Ellisiv B; Johnsen, Stein Harald

    2017-08-01

    CRP predicts cardiovascular disease (CVD) in large epidemiologic studies. The aim of the present study was to elucidate the role of CRP in atherosclerosis formation and progression in a prospective population-based study. 6503 middle-aged subjects from The Tromsø study had serum CRP, carotid ultrasound and complete covariate data collected at baseline in 1994. Of these, 4730 and 2917 attended follow-up surveys with repeated assessments in 2001 and 2007, respectively. The cross-sectional associations between CRP and subclinical carotid atherosclerosis, and the longitudinal associations between baseline CRP and novel plaque formation and plaque progression were assessed in generalized estimating equations and linear mixed models stratified by sex. At baseline, traditional risk factors and plaque prevalence increased by CRP risk categories (<1 mg/L, 1-3 mg/L, and >3 mg/L) in both sexes. In cross-sectional analyses, multivariable-adjusted CRP was associated with plaque prevalence and total plaque area (TPA) in men and women. Age-adjusted baseline CRP >3 mg/L compared to CRP <1 mg/L predicted novel plaque formation (OR 1.44, CI 1.08-1.92) and TPA progression (β = 0.0.029 (CI, 0.003-0.056)) in men, but not in women. In neither men nor women was baseline CRP a predictor of TPA-progression or novel plaque formation when adjusted for traditional risk factors. CRP was associated with plaque presence and TPA in cross-sectional analyses, but was not an independent predictor of novel plaque formation or plaque progression. Our findings suggest that CRP may link to CVD by other mechanisms than promoting formation and progression of atherosclerotic plaques. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Umbilical cord PUFA are determined by maternal and child fatty acid desaturase (FADS) genetic variants in the Avon Longitudinal Study of Parents and Children (ALSPAC).

    PubMed

    Lattka, Eva; Koletzko, Berthold; Zeilinger, Sonja; Hibbeln, Joseph R; Klopp, Norman; Ring, Susan M; Steer, Colin D

    2013-04-14

    Fetal supply with long-chain PUFA (LC-PUFA) during pregnancy is important for brain growth and visual and cognitive development and is provided by materno-fetal placental transfer. We recently showed that maternal fatty acid desaturase (FADS) genotypes modulate the amounts of LC-PUFA in maternal blood. Whether FADS genotypes influence the amounts of umbilical cord fatty acids has not been investigated until now. The aim of the present study was to investigate the influence of maternal and child FADS genotypes on the amounts of LC-PUFA in umbilical cord venous plasma as an indicator of fetal fatty acid supply during pregnancy. A total of eleven cord plasma n-6 and n-3 fatty acids were analysed for association with seventeen FADS gene cluster SNP in over 2000 mothers and children from the Avon Longitudinal Study of Parents and Children. In a multivariable analysis, the maternal genotype effect was adjusted for the child genotype and vice versa to estimate which of the two has the stronger influence on cord plasma fatty acids. Both maternal and child FADS genotypes and haplotypes influenced amounts of cord plasma LC-PUFA and fatty acid ratios. Specifically, most analysed maternal SNP were associated with cord plasma levels of the precursor n-6 PUFA, whereas the child genotypes were mainly associated with more highly desaturated n-6 LC-PUFA. This first study on FADS genotypes and cord fatty acids suggests that fetal LC-PUFA status is determined to some extent by fetal fatty acid conversion. Associations of particular haplotypes suggest specific effects of SNP rs498793 and rs968567 on fatty acid metabolism.

  17. Poverty and Child Development: A Longitudinal Study of the Impact of the Earned Income Tax Credit.

    PubMed

    Hamad, Rita; Rehkopf, David H

    2016-05-01

    Although adverse socioeconomic conditions are correlated with worse child health and development, the effects of poverty-alleviation policies are less understood. We examined the associations of the Earned Income Tax Credit (EITC) on child development and used an instrumental variable approach to estimate the potential impacts of income. We used data from the US National Longitudinal Survey of Youth (n = 8,186) during 1986-2000 to examine effects on the Behavioral Problems Index (BPI) and Home Observation Measurement of the Environment inventory (HOME) scores. We conducted 2 analyses. In the first, we used multivariate linear regressions with child-level fixed effects to examine the association of EITC payment size with BPI and HOME scores; in the second, we used EITC payment size as an instrument to estimate the associations of income with BPI and HOME scores. In linear regression models, higher EITC payments were associated with improved short-term BPI scores (per $1,000, β = -0.57; P = 0.04). In instrumental variable analyses, higher income was associated with improved short-term BPI scores (per $1,000, β = -0.47; P = 0.01) and medium-term HOME scores (per $1,000, β = 0.64; P = 0.02). Our results suggest that both EITC benefits and higher income are associated with modest but meaningful improvements in child development. These findings provide valuable information for health researchers and policymakers for improving child health and development. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Patient Navigation Improves Subsequent Breast Cancer Screening After a Noncancerous Result: Evidence from the Patient Navigation in Medically Underserved Areas Study.

    PubMed

    Molina, Yamile; Kim, Sage J; Berrios, Nerida; Glassgow, Anne Elizabeth; San Miguel, Yazmin; Darnell, Julie S; Pauls, Heather; Vijayasiri, Ganga; Warnecke, Richard B; Calhoun, Elizabeth A

    2018-03-01

    Past efforts to assess patient navigation on cancer screening utilization have focused on one-time uptake, which may not be sufficient in the long term. This is partially due to limited resources for in-person, longitudinal patient navigation. We examine the effectiveness of a low-intensity phone- and mail-based navigation on multiple screening episodes with a focus on screening uptake after receiving noncancerous results during a previous screening episode. The is a secondary analysis of patients who participated in a randomized controlled patient navigation trial in Chicago. Participants include women referred for a screening mammogram, aged 50-74 years, and with a history of benign/normal screening results. Navigation services focused on identification of barriers and intervention via shared decision-making processes. A multivariable logistic regression intent-to-treat model was used to examine differences in odds of obtaining a screening mammogram within 2 years of the initial mammogram (yes/no) between navigated and non-navigated women. Sensitivity analyses were conducted to explore patterns across subsets of participants (e.g., navigated women successfully contacted before the initial appointment; women receiving care at Hospital C). The final sample included 2,536 women (741 navigated, 1,795 non-navigated). Navigated women exhibited greater odds of obtaining subsequent screenings relative to women in the standard care group in adjusted models and analyses including women who received navigation before the initial appointment. Our findings suggest that low-intensity navigation services can improve follow-up screening among women who receive a noncancerous result. Further investigation is needed to confirm navigation's impacts on longitudinal screening.

  19. Changes in Health and Fitness in Firefighter Recruits: An Observational Cohort Study.

    PubMed

    Cornell, David J; Gnacinski, Stacy L; Meyer, Barbara B; Ebersole, Kyle T

    2017-11-01

    To observe longitudinal changes in health and fitness among firefighter recruits. Body composition, aerobic capacity, muscular power, muscular strength, and muscular endurance measures were longitudinally collected among 27 male firefighter recruits (mean ± SD, age = 29.9 ± 4.1 yr; height, 179.8 ± 4.6 cm; body mass, 87.2 ± 9.7 kg) at the beginning (W1) and end (W14) of their firefighter training academy, as well as at the end of their probationary period (W38). Repeated-measures multivariate analyses of variance (RM MANOVA) identified significant changes across time among measures of body composition (F10,17 = 30.390, Λ = 0.053, P < 0.001), aerobic capacity (F6,21 = 55.111, Λ = 0.060, P < 0.001), muscular power (F8,17 = 2.785, Λ = 0.433, P = 0.036), muscular strength (F6,20 = 34.908, Λ = 0.087, P < 0.001), and muscular endurance (F4,23 = 25.983, Λ = 0.181, P < 0.001). Follow-up post hoc analyses indicated that all measures, except muscular power, significantly improved from W1 to W14 (P < 0.05). However, significant decrements in many of these measures were also observed from W14 to W38 (P < 0.05). The results of the current study suggest that measures of health and fitness among firefighter recruits significantly improved throughout the firefighter training academy (W1 to W14). However, many of these positive physiological adaptations are lost before these recruits finish their probationary period as active-duty firefighters (W14 to W38). These results highlight the importance of developing exercise programming that is designed for the active-duty firefighter cohort population to maintain the beneficial adaptations in health and fitness previously created during the firefighter training academy.

  20. A longitudinal examination of US teen childbearing and smoking risk.

    PubMed

    Mollborn, Stefanie; Woo, Juhee; Rogers, Richard G

    2018-01-01

    Teenage motherhood and smoking have important health implications for youth in the United States and globally, but the link between teen childbearing and subsequent smoking is inadequately understood. The selection of disadvantaged young women into early childbearing and smoking may explain higher smoking levels among teen mothers, but teen motherhood may also shape subsequent smoking through compromised maternal depression or socioeconomic status, and race/ethnicity may condition these processes. This study examines the relationship between US teen childbearing and subsequent daily smoking, accounting for prior smoking and selection processes related to social disadvantage. Analyses investigate whether socioeconomic status and depression in young adulthood explained any relationship between teen childbearing and daily smoking, as well as examining racial/ethnic heterogeneity in these processes. Multivariate binary logistic regression analyses employ the National Longitudinal Study of Adolescent to Adult Health (Add Health; N = 7,529). The highest daily smoking prevalence occurred among non-Hispanic White teen mothers, with lower prevalence among Hispanic and non-Hispanic Black teen mothers. Compared to other women, teenage mothers are 2.5 times as likely to smoke daily in young adulthood. Their greater likelihood of daily smoking is due in part to selection and is also mediated by socioeconomic status in ways that differ by race/ethnicity. The findings suggest that preventing teen pregnancy or ameliorating its socioeconomic consequences may decrease daily smoking in this vulnerable population. Reducing teen smoking, especially during pregnancy, could improve teen, maternal, and infant health and thereby increase US health and longevity. This study provides new, nationally representative information about selection, mediation, and heterogeneity processes in the relationship between teen childbearing and subsequent smoking.

  1. A longitudinal examination of US teen childbearing and smoking risk

    PubMed Central

    Mollborn, Stefanie; Woo, Juhee; Rogers, Richard G.

    2018-01-01

    BACKGROUND Teenage motherhood and smoking have important health implications for youth in the United States and globally, but the link between teen childbearing and subsequent smoking is inadequately understood. The selection of disadvantaged young women into early childbearing and smoking may explain higher smoking levels among teen mothers, but teen motherhood may also shape subsequent smoking through compromised maternal depression or socioeconomic status, and race/ethnicity may condition these processes. OBJECTIVE This study examines the relationship between US teen childbearing and subsequent daily smoking, accounting for prior smoking and selection processes related to social disadvantage. Analyses investigate whether socioeconomic status and depression in young adulthood explained any relationship between teen childbearing and daily smoking, as well as examining racial/ethnic heterogeneity in these processes. METHODS Multivariate binary logistic regression analyses employ the National Longitudinal Study of Adolescent to Adult Health (Add Health; N = 7,529). RESULTS The highest daily smoking prevalence occurred among non-Hispanic White teen mothers, with lower prevalence among Hispanic and non-Hispanic Black teen mothers. Compared to other women, teenage mothers are 2.5 times as likely to smoke daily in young adulthood. Their greater likelihood of daily smoking is due in part to selection and is also mediated by socioeconomic status in ways that differ by race/ethnicity. CONCLUSIONS The findings suggest that preventing teen pregnancy or ameliorating its socioeconomic consequences may decrease daily smoking in this vulnerable population. Reducing teen smoking, especially during pregnancy, could improve teen, maternal, and infant health and thereby increase US health and longevity. CONTRIBUTION This study provides new, nationally representative information about selection, mediation, and heterogeneity processes in the relationship between teen childbearing and subsequent smoking. PMID:29618943

  2. Gamma-glutamyltransferase, fatty liver index and hepatic insulin resistance are associated with incident hypertension in two longitudinal studies.

    PubMed

    Bonnet, Fabrice; Gastaldelli, Amalia; Pihan-Le Bars, Florence; Natali, Andrea; Roussel, Ronan; Petrie, John; Tichet, Jean; Marre, Michel; Fromenty, Bernard; Balkau, Beverley

    2017-03-01

    We hypothesized that liver markers and the fatty liver index (FLI) are predictive of incident hypertension and that hepatic insulin resistance plays a role. The association between liver markers and incident hypertension was analysed in two longitudinal studies of normotensive individuals, 2565 from the 9-year data from an epidemiological study on the insulin resistance cohort and the 321 from the 3-year 'Relationship between Insulin Sensitivity and Cardiovascular disease' cohort who had a measure of endogenous glucose production. The FLI is calculated from BMI, waist circumference, triglycerides and gamma-glutamyltransferase (GGT) and the hepatic insulin resistance index from endogenous glucose production and fasting insulin. The incidence of hypertension increased across the quartiles groups of both baseline GGT and alanine aminotransferase. After adjustment for sex, age, waist circumference, fasting glucose, smoking and alcohol intake, only GGT was significantly related with incident hypertension [standardized odds ratio: 1.21; 95% confidence interval (1.10-1.34); P = 0.0001]. The change in GGT levels over the follow-up was also related with an increased risk of hypertension, independently of changes in body weight. FLI analysed as a continuous value, or FLI at least 60 at baseline were predictive of incident hypertension in the multivariable model. In the RISC cohort, the hepatic insulin resistance index was positively related with the risk of 3-year incident hypertension [standardized odds ratio: 1.54 (1.07-2.22); P = 0.02]. Baseline GGT and FLI, as well as an increase in GGT over time, were associated with the risk of incident hypertension. Enhanced hepatic insulin resistance predicted the onset of hypertension and may be a link between liver markers and hypertension.

  3. Admissions to inpatient care facilities in the last year of life of community-dwelling older people in Europe.

    PubMed

    Overbeek, Anouk; Van den Block, Lieve; Korfage, Ida J; Penders, Yolanda W H; van der Heide, Agnes; Rietjens, Judith A C

    2017-10-01

    In the last year of life, many older people rather avoid admissions to inpatient care facilities. We describe and compare such admissions in the last year of life of 5092 community-dwelling older people in 15 European countries (+Israel). Proxy-respondents of the older people, who participated in the longitudinal SHARE study, reported on admissions to inpatient care facilities (hospital, nursing home or hospice) during the last year of their life. Multivariable regression analyses assessed associations between hospitalizations and personal/contextual characteristics. The proportion of people who had been admitted at least once to an inpatient care facility in the last year of life ranged from 54% (France) to 76% (Austria, Israel, Slovenia). Admissions mostly concerned hospitalizations. Multivariable analyses showed that especially Austrians, Israelis and Poles had higher chances of being hospitalized. Further, hospitalizations were more likely for those being ill for 6 months or more (OR:1.67, CI:1.39-2.01), and less likely for persons aged 80+ (OR:0.54, CI:0.39-0.74; compared with 48-65 years), females (OR:0.74, CI:0.63-0.89) and those dying of cardiovascular diseases (OR:0.66, CI:0.51-0.86; compared with those dying of cancer). Although healthcare policies increasingly stress the importance that people reside at home as long as possible, admissions to inpatient care facilities in the last year of life are relatively common across all countries. Furthermore, we found a striking variation concerning the proportion of admissions across countries which cannot only be explained by patient needs. It suggests that such admissions are at least partly driven by system-level or cultural factors. © The Author 2017. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

  4. High-intensity cannabis use associated with lower plasma human immunodeficiency virus-1 RNA viral load among recently infected people who use injection drugs.

    PubMed

    Milloy, M-J; Marshall, Brandon; Kerr, Thomas; Richardson, Lindsey; Hogg, Robert; Guillemi, Silvia; Montaner, Julio S G; Wood, Evan

    2015-03-01

    Cannabis use is common among people who are living with human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS). While there is growing pre-clinical evidence of the immunomodulatory and anti-viral effects of cannabinoids, their possible effects on HIV disease parameters in humans are largely unknown. Thus, we sought to investigate the possible effects of cannabis use on plasma HIV-1 RNA viral loads (pVLs) among recently seroconverted illicit drug users. We used data from two linked longitudinal observational cohorts of people who use injection drugs. Using multivariable linear mixed-effects modelling, we analysed the relationship between pVL and high-intensity cannabis use among participants who seroconverted following recruitment. Between May 1996 and March 2012, 88 individuals seroconverted after recruitment and were included in these analyses. Median pVL in the first 365 days among all seroconverters was 4.66 log10 c mL(-1) . In a multivariable model, at least daily cannabis use was associated with 0.51 log10 c mL(-1) lower pVL (β = -0.51, standard error = 0.170, P value = 0.003). Consistent with the findings from recent in vitro and in vivo studies, including one conducted among lentiviral-infected primates, we observed a strong association between cannabis use and lower pVL following seroconversion among illicit drug-using participants. Our findings support the further investigation of the immunomodulatory or antiviral effects of cannabinoids among individuals living with HIV/AIDS. © 2014 Australasian Professional Society on Alcohol and other Drugs.

  5. Psychological and relational correlates of intimate partner violence profiles among pregnant adolescent couples.

    PubMed

    Lewis, Jessica B; Sullivan, Tami P; Angley, Meghan; Callands, Tamora; Divney, Anna A; Magriples, Urania; Gordon, Derrick M; Kershaw, Trace S

    2017-01-01

    We sought to identify relationship and individual psychological factors that related to four profiles of intimate partner violence (IPV) among pregnant adolescent couples: no IPV, male IPV victim only, female IPV victim only, mutual IPV, and how associations differ by sex. Using data from a longitudinal study of pregnant adolescents and partners (n = 291 couples), we used a multivariate profile analysis using multivariate analysis of covariance with between and within-subjects effects to compare IPV groups and sex on relationship and psychological factors. Analyses were conducted at the couple level, with IPV groups as a between-subjects couple level variable and sex as a within-subjects variable that allowed us to model and compare the outcomes of both partners while controlling for the correlated nature of the data. Analyses controlled for age, race, income, relationship duration, and gestational age. Among couples, 64% had no IPV; 23% male IPV victim only; 7% mutual IPV; 5% female IPV victim only. Relationship (F = 3.61, P < .001) and psychological (F = 3.17, P < .001) factors differed by IPV group, overall. Attachment anxiety, attachment avoidance, relationship equity, perceived partner infidelity, depression, stress, and hostility each differed by IPV profile (all P < .01). Attachment anxiety, equity, depression and stress had a significant IPV profile by sex interaction (all P < .05). Couples with mutual IPV had the least healthy relationship and psychological characteristics; couples with no IPV had the healthiest characteristics. Females in mutually violent relationships were at particularly high risk. Couple-level interventions focused on relational issues might protect young families from developing IPV behaviors. Aggr. Behav. 43:26-36, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  6. Childhood internalizing and externalizing problems predict the onset of clinical panic attacks over adolescence: the TRAILS study.

    PubMed

    Mathyssek, Christina M; Olino, Thomas M; Verhulst, Frank C; van Oort, Floor V A

    2012-01-01

    Panic attacks are a source of individual suffering and are an independent risk factor for later psychopathology. However, much less is known about risk factors for the development of panic attacks, particularly during adolescence when the incidence of panic attacks increases dramatically. We examined whether internalizing and externalizing problems in childhood predict the onset of panic attacks in adolescence. This study is part of the TRacking Adolescents' Individual Lives Survey (TRAILS), a Dutch longitudinal population cohort study (N = 1,584). Internalizing and Externalizing Problems were collected using the Youth Self-Report (YSR) and the parent-report Child Behavior Checklist (CBCL) at baseline (age 10-12). At age 18-20, DSM-IV defined panic attacks since baseline were assessed with the Composite International Diagnostic Interview (CIDI). We investigated whether early adolescent Internalizing and Externalizing Problems predicted panic attacks between ages 10-20 years, using survival analysis in univariate and multivariate models. There were N = 314 (19.8%) cases who experienced at least one DSM-IV defined panic attack during adolescence and N = 18 (1.2%) who developed panic disorder during adolescence. In univariate analyses, CBCL Total Problems, Internalizing Problems and three of the eight syndrome scales predicted panic attack onset, while on the YSR all broad-band problem scales and each narrow-band syndrome scale predicted panic attack onset. In multivariate analyses, CBCL Social Problems (HR 1.19, p<.05), and YSR Thought Problems (HR 1.15, p<.05) and Social Problems (HR 1.26, p<.01) predicted panic attack onset. Risk indicators of panic attack include the wide range of internalizing and externalizing problems. Yet, when adjusted for co-occurring problem behaviors, Social Problems were the most consistent risk factor for panic attack onsets in adolescence.

  7. Biphasic decline in renal function after radical cystectomy with urinary diversion.

    PubMed

    Makino, Katsuhiro; Nakagawa, Tohru; Kanatani, Atsushi; Kawai, Taketo; Taguchi, Satoru; Otsuka, Masafumi; Matsumoto, Akihiko; Miyazaki, Hideyo; Fujimura, Tetsuya; Fukuhara, Hiroshi; Kume, Haruki; Homma, Yukio

    2017-04-01

    We evaluated short- and long-term renal function in patients after radical cystectomy with urinary diversion and identified risk factors for the deterioration of renal function. This retrospective study comprised 91 patients who underwent radical cystectomy and urinary diversion for bladder cancer and survived ≥3 years after surgery. The estimated glomerular filtration rate (eGFR) was calculated, and longitudinal changes of eGFR were assessed. Deterioration in renal function in early and late postoperative years was defined as a ≥25 % decrease in the eGFR from preoperative to postoperative year one, and a reduction in the eGFR of >1 mL/min/1.73 m 2 annually in subsequent years, respectively. Univariate and multivariate logistic regression analyses were used to evaluate its association with clinicopathologic features. The median follow-up period after surgery was 7 years (range 3-26). The mean eGFR decreased from preoperative 65.1 to 58.9 mL/min/1.73 m 2 1 year after the surgery, followed by a continuous decline of ~1.0 mL/min/1.73 m 2 per year thereafter. Multivariate analyses identified ureteroenteric stricture as the sole risk factor associated with early renal function deterioration [odds ratio (OR) 4.22, p = 0.037]. Diabetes mellitus (OR 8.24, p = 0.015) and episodes of pyelonephritis (OR 4.89, p = 0.038) were independently associated with the gradual decline in the late postoperative period. In cystectomy patients with urinary diversion, the rapid deterioration of renal function observed during the first year after surgery and the gradual but continuous decline in function thereafter were found to be associated with different risk factors.

  8. Association of sleep apnea and sleep duration with peripheral artery disease: The Multi-Ethic Study of Atherosclerosis (MESA)

    PubMed Central

    Nagayoshi, Mako; Lutsey, Pamela L.; Benkeser, David; Wassel, Christina L.; Folsom, Aaron R.; Shahar, Eyal; Iso, Hiroyasu; Allison, Matthew A.; Criqui, Michael H.; Redline, Susan

    2016-01-01

    Background and aims Numerous biological pathways linking sleep disturbances to atherosclerosis have been identified, such as insulin resistance, inflammation, hypertension, and endothelial dysfunction. Yet, the association of sleep apnea and sleep duration with peripheral artery disease (PAD) is not well characterized. Methods We evaluated the cross-sectional association between objectively measured sleep and prevalent PAD in 1,844 participants (mean age 68 years) who in 2010–2013 had in-home polysomnography, 7-day wrist actigraphy and ankle-brachial index (ABI) measurements. We also evaluated the relation between self-reported diagnosed sleep apnea and PAD incidence in 5,365 participants followed from 2000 to 2012. PAD was defined as ABI<0.90. Results In cross-sectional analyses, severe sleep apnea [apnea-hypopnea index (AHI) ≥30 vs. AHI <5] was associated with greater prevalent PAD only among black participants [multivariate adjusted prevalence ratio (95% CI): 2.29 (1.07–4.89); p-interaction = 0.05]. Short and long sleep duration was also associated with a 2-fold higher prevalence of PAD as compared with those who slept 7h/night, in the full sample. In longitudinal analyses, participants with self-reported diagnosed sleep apnea were at higher risk of incident PAD [multivariable adjusted hazard ratio (95% CI): 1.93 (1.05–3.53)], with no evidence of interaction by race/ethnicity. Conclusions These findings support a significant association between sleep apnea and prevalent and incident PAD, with evidence for stronger associations with objectively measured sleep apnea and cross sectional PAD in blacks. In addition, short and long sleep duration was associated with PAD. These results identify sleep disturbances as a potential risk factor for PAD. PMID:27423537

  9. Quantitative genetics of age at reproduction in wild swans: Support for antagonistic pleiotropy models of senescence

    PubMed Central

    Charmantier, Anne; Perrins, Christopher; McCleery, Robin H.; Sheldon, Ben C.

    2006-01-01

    Why do individuals stop reproducing after a certain age, and how is this age determined? The antagonistic pleiotropy theory for the evolution of senescence predicts that increased early-life performance should be accompanied by earlier (or faster) senescence. Hence, an individual that has started to breed early should also lose its reproductive capacities early. We investigate here the relationship between age at first reproduction (AFR) and age at last reproduction (ALR) in a free-ranging mute swan (Cygnus olor) population monitored for 36 years. Using multivariate analyses on the longitudinal data, we show that both traits are strongly selected in opposite directions. Analysis of the phenotypic covariance between these characters shows that individuals vary in their inherent quality, such that some individuals have earlier AFR and later ALR than expected. Quantitative genetic pedigree analyses show that both traits possess additive genetic variance but also that AFR and ALR are positively genetically correlated. Hence, although both traits display heritable variation and are under opposing directional selection, their evolution is constrained by a strong evolutionary tradeoff. These results are consistent with the theory that increased early-life performance comes with faster senescence because of genetic tradeoffs. PMID:16618935

  10. Personality Traits as Prospective Predictors of Suicide Attempts

    PubMed Central

    Yen, Shirley; Shea, M. Tracie; Sanislow, Charles A.; Skodol, Andrew E.; Grilo, Carlos M.; Edelen, Maria Orlando; Stout, Robert L.; Morey, Leslie C.; Zanarini, Mary C.; Markowitz, John C.; McGlashan, Thomas H.; Daversa, Maria T.; Gunderson, John G.

    2009-01-01

    OBJECTIVE To examine higher order personality factors of negative affectivity (NA) and disinhibition (DIS), as well as lower order facets of impulsivity, as prospective predictors of suicide attempts in a predominantly personality disordered (PD) sample. METHOD Data were analyzed from 701 participants of the Collaborative Longitudinal Personality Disorders Study (CLPS) with available follow-up data for up to 7 years. Cox proportional hazards regression analyses was used to examine NA and DIS, and facets of impulsivity (e.g., urgency, lack of perseverance, lack of premeditation, and sensation seeking), as prospective predictors of suicide attempts. RESULTS NA, DIS, and all facets of impulsivity except for sensation seeking were significant in univariate analyses. In multivariate models which included sex, childhood sexual abuse (CSA), course of major depressive disorder (MDD) and substance use disorders (SUD), only NA and lack of premeditation remained significant in predicting suicide attempts. Disinhibition and the remaining impulsivity facets were not significant. CONCLUSION Negative affectivity emerged as a stronger and more robust predictor of suicide attempts than disinhibition and impulsivity, and warrants greater attention in suicide risk assessment. Distinguishing between facets of impulsivity is important for clinical risk assessment. PMID:19298413

  11. Multivariate Models for Normal and Binary Responses in Intervention Studies

    ERIC Educational Resources Information Center

    Pituch, Keenan A.; Whittaker, Tiffany A.; Chang, Wanchen

    2016-01-01

    Use of multivariate analysis (e.g., multivariate analysis of variance) is common when normally distributed outcomes are collected in intervention research. However, when mixed responses--a set of normal and binary outcomes--are collected, standard multivariate analyses are no longer suitable. While mixed responses are often obtained in…

  12. Low back pain and limitations of daily living in Asia: longitudinal findings in the Thai cohort study.

    PubMed

    Yiengprugsawan, Vasoontara; Hoy, Damian; Buchbinder, Rachelle; Bain, Chris; Seubsman, Sam-Ang; Sleigh, Adrian C

    2017-01-19

    Low back pain (LBP) is a major cause of disability throughout the world. However, longitudinal evidence to relate low back pain and functional limitations is mostly confined to Western countries. In this study, we investigate the associations between low back pain and functional limitations in a prospective cohort of Thai adults. We analysed information from the Thai Cohort Study of adult Open University adults which included 42,785 participants in both 2009 and 2013, with the majority aged 30 to 65 years and residing nationwide. We used multivariate logistic regression to explore the longitudinal associations between LBP in 2009 and 2013 ('never': no LBP in 2009 or 2013; 'reverting': LBP in 2009 but not in 2013; 'incident': no LBP in 2009 but LBP in 2013; and 'chronic': reporting LBP at both time points) and the outcome of functional limitations relating to Activities of Daily Living (ADL) in 2013. Low back pain was common with 30% of cohort members reporting low back pain in both 2009 and 2013 ('chronic LBP'). The 'chronic LBP' group was more likely than the 'never' back pain group to report functional limitations in 2013: adjusted odds ratios 1.60 [95% Confidence Interval: 1.38-1.85] for difficulties getting dressed; 1.98 [1.71-2.30] for walking; 2.02 [1.71-2.39] for climbing stairs; and 3.80 [3.38-4.27] for bending/kneeling. Those with 'incident LBP' or 'reverting LBP' both had increased odds of functional limitations in 2013 but the odds were not generally as high. Our nationwide data from Thailand suggests that LBP is a frequent public health problem among economically productive age groups with adverse effects on the activities of daily living. This study adds to the limited longitudinal evidence on the substantial impact of low back pain in Southeast Asia.

  13. Clinical Implications of a Dimensional Approach: The Normal:Abnormal Spectrum of Early Irritability.

    PubMed

    Wakschlag, Lauren S; Estabrook, Ryne; Petitclerc, Amelie; Henry, David; Burns, James L; Perlman, Susan B; Voss, Joel L; Pine, Daniel S; Leibenluft, Ellen; Briggs-Gowan, Margaret L

    2015-08-01

    The importance of dimensional approaches is widely recognized, but an empirical base for clinical application is lacking. This is particularly true for irritability, a dimensional phenotype that cuts across many areas of psychopathology and manifests early in life. We examine longitudinal, dimensional patterns of irritability and their clinical import in early childhood. Irritability was assessed longitudinally over an average of 16 months in a clinically enriched, diverse community sample of preschoolers (N = 497; mean = 4.2 years; SD = 0.8). Using the Temper Loss scale of the Multidimensional Assessment Profile of Disruptive Behavior (MAP-DB) as a developmentally sensitive indicator of early childhood irritability, we examined its convergent/divergent, clinical, and incremental predictive validity, and modeled its linear and nonlinear associations with clinical risk. The Temper Loss scale demonstrated convergent and divergent validity to child and maternal factors. In multivariate analyses, Temper Loss predicted mood (separation anxiety disorder [SAD], generalized anxiety disorder [GAD], and depression/dysthymia), disruptive (oppositional defiant disorder [ODD], attention-deficit/hyperactivity disorder [ADHD], and conduct disorder [CD]) symptoms. Preschoolers with even mildly elevated Temper Loss scale scores showed substantially increased risk of symptoms and disorders. For ODD, GAD, SAD, and depression, increases in Temper Loss scale scores at the higher end of the dimension had a greater impact on symptoms relative to increases at the lower end. Temper Loss scale scores also showed incremental validity over DSM-IV disorders in predicting subsequent impairment. Finally, accounting for the substantial heterogeneity in longitudinal patterns of Temper Loss significantly improved prediction of mood and disruptive symptoms. Dimensional, longitudinal characterization of irritability informs clinical prediction. A vital next step will be empirically generating parameters for the incorporation of dimensional information into clinical decision-making with reasonable certainty. Copyright © 2015 American Academy of Child and Adolescent Psychiatry. All rights reserved.

  14. HbA1c, diabetes and cognitive decline: the English Longitudinal Study of Ageing.

    PubMed

    Zheng, Fanfan; Yan, Li; Yang, Zhenchun; Zhong, Baoliang; Xie, Wuxiang

    2018-04-01

    The aim of the study was to evaluate longitudinal associations between HbA 1c levels, diabetes status and subsequent cognitive decline over a 10 year follow-up period. Data from wave 2 (2004-2005) to wave 7 (2014-2015) of the English Longitudinal Study of Ageing (ELSA) were analysed. Cognitive function was assessed at baseline (wave 2) and reassessed every 2 years at waves 3-7. Linear mixed models were used to evaluate longitudinal associations. The study comprised 5189 participants (55.1% women, mean age 65.6 ± 9.4 years) with baseline HbA 1c levels ranging from 15.9 to 126.3 mmol/mol (3.6-13.7%). The mean follow-up duration was 8.1 ± 2.8 years and the mean number of cognitive assessments was 4.9 ± 1.5. A 1 mmol/mol increment in HbA 1c was significantly associated with an increased rate of decline in global cognitive z scores (-0.0009 SD/year, 95% CI -0.0014, -0.0003), memory z scores (-0.0005 SD/year, 95% CI -0.0009, -0.0001) and executive function z scores (-0.0008 SD/year, 95% CI -0.0013, -0.0004) after adjustment for baseline age, sex, total cholesterol, HDL-cholesterol, triacylglycerol, high-sensitivity C-reactive protein, BMI, education, marital status, depressive symptoms, current smoking, alcohol consumption, hypertension, CHD, stroke, chronic lung disease and cancer. Compared with participants with normoglycaemia, the multivariable-adjusted rate of global cognitive decline associated with prediabetes and diabetes was increased by -0.012 SD/year (95% CI -0.022, -0.002) and -0.031 SD/year (95% CI -0.046, -0.015), respectively (p for trend <0.001). Similarly, memory, executive function and orientation z scores showed an increased rate of cognitive decline with diabetes. Significant longitudinal associations between HbA 1c levels, diabetes status and long-term cognitive decline were observed in this study. Future studies are required to determine the effects of maintaining optimal glucose control on the rate of cognitive decline in people with diabetes.

  15. Motion Predicts Clinical Callus Formation

    PubMed Central

    Elkins, Jacob; Marsh, J. Lawrence; Lujan, Trevor; Peindl, Richard; Kellam, James; Anderson, Donald D.; Lack, William

    2016-01-01

    Background: Mechanotransduction is theorized to influence fracture-healing, but optimal fracture-site motion is poorly defined. We hypothesized that three-dimensional (3-D) fracture-site motion as estimated by finite element (FE) analysis would influence callus formation for a clinical series of supracondylar femoral fractures treated with locking-plate fixation. Methods: Construct-specific FE modeling simulated 3-D fracture-site motion for sixty-six supracondylar femoral fractures (OTA/AO classification of 33A or 33C) treated at a single institution. Construct stiffness and directional motion through the fracture were investigated to assess the validity of construct stiffness as a surrogate measure of 3-D motion at the fracture site. Callus formation was assessed radiographically for all patients at six, twelve, and twenty-four weeks postoperatively. Univariate and multivariate linear regression analyses examined the effects of longitudinal motion, shear (transverse motion), open fracture, smoking, and diabetes on callus formation. Construct types were compared to determine whether their 3-D motion profile was associated with callus formation. Results: Shear disproportionately increased relative to longitudinal motion with increasing bridge span, which was not predicted by our assessment of construct stiffness alone. Callus formation was not associated with open fracture, smoking, or diabetes at six, twelve, or twenty-four weeks. However, callus formation was associated with 3-D fracture-site motion at twelve and twenty-four weeks. Longitudinal motion promoted callus formation at twelve and twenty-four weeks (p = 0.017 for both). Shear inhibited callus formation at twelve and twenty-four weeks (p = 0.017 and p = 0.022, respectively). Titanium constructs with a short bridge span demonstrated greater longitudinal motion with less shear than did the other constructs, and this was associated with greater callus formation (p < 0.001). Conclusions: In this study of supracondylar femoral fractures treated with locking-plate fixation, longitudinal motion promoted callus formation, while shear inhibited callus formation. Construct stiffness was found to be a poor surrogate of fracture-site motion. Future implant design and operative fixation strategies should seek to optimize 3-D fracture-site motion rather than rely on surrogate measures such as axial stiffness. PMID:26888675

  16. Multiple Indicator Stationary Time Series Models.

    ERIC Educational Resources Information Center

    Sivo, Stephen A.

    2001-01-01

    Discusses the propriety and practical advantages of specifying multivariate time series models in the context of structural equation modeling for time series and longitudinal panel data. For time series data, the multiple indicator model specification improves on classical time series analysis. For panel data, the multiple indicator model…

  17. A Computer Interview for Multivariate Monitoring of Psychiatric Outcome.

    ERIC Educational Resources Information Center

    Stevenson, John F.; And Others

    Application of computer technology to psychiatric outcome measurement offers the promise of coping with increasing demands for extensive patient interviews repeated longitudinally. Described is the development of a cost-effective multi-dimensional tracking device to monitor psychiatric functioning, building on a previous local computer interview…

  18. Systems and Cascades in Cognitive Development and Academic Achievement

    ERIC Educational Resources Information Center

    Bornstein, Marc H.; Hahn, Chun-Shin; Wolke, Dieter

    2013-01-01

    A large-scale ("N" = 552) controlled multivariate prospective 14-year longitudinal study of a developmental cascade embedded in a developmental system showed that information-processing efficiency in infancy (4 months), general mental development in toddlerhood (18 months), behavior difficulties in early childhood (36 months),…

  19. Multilingualism and fMRI: Longitudinal Study of Second Language Acquisition

    PubMed Central

    Andrews, Edna; Frigau, Luca; Voyvodic-Casabo, Clara; Voyvodic, James; Wright, John

    2013-01-01

    BOLD fMRI is often used for the study of human language. However, there are still very few attempts to conduct longitudinal fMRI studies in the study of language acquisition by measuring auditory comprehension and reading. The following paper is the first in a series concerning a unique longitudinal study devoted to the analysis of bi- and multilingual subjects who are: (1) already proficient in at least two languages; or (2) are acquiring Russian as a second/third language. The focus of the current analysis is to present data from the auditory sections of a set of three scans acquired from April, 2011 through April, 2012 on a five-person subject pool who are learning Russian during the study. All subjects were scanned using the same protocol for auditory comprehension on the same General Electric LX 3T Signa scanner in Duke University Hospital. Using a multivariate analysis of covariance (MANCOVA) for statistical analysis, proficiency measurements are shown to correlate significantly with scan results in the Russian conditions over time. The importance of both the left and right hemispheres in language processing is discussed. Special attention is devoted to the importance of contextualizing imaging data with corresponding behavioral and empirical testing data using a multivariate analysis of variance. This is the only study to date that includes: (1) longitudinal fMRI data with subject-based proficiency and behavioral data acquired in the same time frame; and (2) statistical modeling that demonstrates the importance of covariate language proficiency data for understanding imaging results of language acquisition. PMID:24961428

  20. Multilingualism and fMRI: Longitudinal Study of Second Language Acquisition.

    PubMed

    Andrews, Edna; Frigau, Luca; Voyvodic-Casabo, Clara; Voyvodic, James; Wright, John

    2013-05-28

    BOLD fMRI is often used for the study of human language. However, there are still very few attempts to conduct longitudinal fMRI studies in the study of language acquisition by measuring auditory comprehension and reading. The following paper is the first in a series concerning a unique longitudinal study devoted to the analysis of bi- and multilingual subjects who are: (1) already proficient in at least two languages; or (2) are acquiring Russian as a second/third language. The focus of the current analysis is to present data from the auditory sections of a set of three scans acquired from April, 2011 through April, 2012 on a five-person subject pool who are learning Russian during the study. All subjects were scanned using the same protocol for auditory comprehension on the same General Electric LX 3T Signa scanner in Duke University Hospital. Using a multivariate analysis of covariance (MANCOVA) for statistical analysis, proficiency measurements are shown to correlate significantly with scan results in the Russian conditions over time. The importance of both the left and right hemispheres in language processing is discussed. Special attention is devoted to the importance of contextualizing imaging data with corresponding behavioral and empirical testing data using a multivariate analysis of variance. This is the only study to date that includes: (1) longitudinal fMRI data with subject-based proficiency and behavioral data acquired in the same time frame; and (2) statistical modeling that demonstrates the importance of covariate language proficiency data for understanding imaging results of language acquisition.

  1. Exhaled breath condensate adenosine tracks lung function changes in cystic fibrosis

    PubMed Central

    Olsen, Bonnie M.; Lin, Feng-Chang; Fine, Jason; Boucher, Richard C.

    2013-01-01

    Measurement of exhaled breath condensate (EBC) biomarkers offers a noninvasive means to assess airway disease, but the ability of EBC biomarkers to track longitudinal changes in disease severity remains unproven. EBC was collected from pediatric patients with cystic fibrosis (CF) during regular clinic visits over 1 yr. EBC biomarkers urea, adenosine (Ado), and phenylalanine (Phe) were measured by mass spectrometry, and biomarker ratios were used to control for variable dilution of airway secretions. EBC biomarker ratios were assessed relative to lung function in longitudinal, multivariate models and compared with sputum inflammatory markers and quality of life assessment (CFQ-R). EBC was successfully analyzed from 51 subjects during 184 visits (3.6 ± 0.9 visits per subject). EBC Ado/urea ratio was reproducible in duplicate samples (r = 0.62, P < 0.01, n = 20) and correlated with sputum neutrophil elastase (β = 2.5, P < 0.05). EBC Ado/urea correlated with the percentage predicted of forced expiratory volume in 1 s in longitudinal, multivariate models (β = −2.9, P < 0.01); EBC Ado/Phe performed similarly (β = −2.1, P < 0.05). In contrast, IL-8 and elastase measured in spontaneously expectorated sputum (n = 57 samples from 25 subjects) and the CFQ-R respiratory scale (n = 90 tests from 47 subjects) were not significantly correlated with lung function. EBC was readily collected in a clinic setting from a wide range of subjects. EBC Ado tracked longitudinal changes in lung function in CF, with results similar to or better than established measures. PMID:23355385

  2. Longitudinal association between time-varying social isolation and psychological distress after the Great East Japan Earthquake.

    PubMed

    Sone, Toshimasa; Nakaya, Naoki; Sugawara, Yumi; Tomata, Yasutake; Watanabe, Takashi; Tsuji, Ichiro

    2016-03-01

    The association between social isolation and psychological distress among disaster survivors is inconclusive. In addition, because these previous studies were cross-sectional in design, the longitudinal association between time-varying social isolation and psychological distress was not clear. The present study examined the longitudinal association between social isolation and psychological distress after the Great East Japan Earthquake. We analyzed longitudinal data for 959 adults who had responded to the self-report questionnaires about Lubben Social Network Scale-6 (LSNS-6) and K6 in both a community-based baseline survey (2011) and a follow-up survey (2014) after the disaster. Participants were categorized into four groups according to changes in the presence of social isolation (<12/30 of LSNS-6) at two time points (2011 and 2014): "remained socially isolated", "became not socially isolated", "remained not socially isolated", and "became socially isolated". We defined a K6 score of ≥ 10/24 as indicating the presence of psychological distress. We used multiple logistic regression analysis to estimate the adjusted odds ratios (ORs) and 95% confidence intervals (CIs) to indicate how the change in social isolation was related to changes in psychological distress over 3 years. Among the participants who had not shown psychological distress at the baseline, the rates of deterioration of psychological distress were significantly lower in participants who "became not socially isolated" (multivariate OR = 0.26, 95% CI = 0.08-0.70) and "remained not socially isolated" (multivariate OR = 0.49, 95% CI = 0.27-0.91), compared with participants who "remained socially isolated". Among the participants who had psychological distress at the baseline, the rate of improvement of psychological distress was significantly higher in participants who "remained not socially isolated" (multivariate OR = 2.61, 95% CI = 1.08-6.44). The present findings suggest that prevention of social isolation may be an effective public health strategy for preventing psychological distress after a natural disaster. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Period of residence in prefabricated temporary housing and psychological distress after the Great East Japan Earthquake: a longitudinal study

    PubMed Central

    Tanji, Fumiya; Tomata, Yasutake; Sekiguchi, Takuya; Tsuji, Ichiro

    2018-01-01

    Objectives Previous studies have reported that displacement from one’s own home after a natural disaster is associated with a higher degree of psychological distress. The present study investigated the longitudinal association between the period of residence in prefabricated temporary housing and psychological distress after the Great East Japan Earthquake. Design, setting and participants We conducted a longitudinal observation of 284 adults (aged ≥18 years) who had lived in prefabricated temporary housing in Miyagi, Northeastern Japan. The period of residence in prefabricated temporary housing was classified into three categories: <3, 3–4 and >4 years (ie, still living in prefabricated temporary housing). Outcomes The Kessler 6-item Psychological Distress Scale (K6) was assessed in both a baseline survey (2011) and a follow-up survey (2016). Higher psychological distress was defined by a K6 score of ≥5. We used Firth’s penalised likelihood method in the multivariate logistic regression model to estimate the adjusted ORs and 95% CIs. Results Among the total participants, the proportion of individuals with higher psychological distress at the follow-up survey was significantly higher in the >4 years category (multivariate OR=4.00, 95% CI 1.67 to 10.16) than in the <3 years category. Among participants who had a lower degree of psychological distress at the baseline, the proportion of those whose psychological distress deteriorated was significantly higher in the >4 years category (multivariate OR=4.87, 95% CI 1.26 to 20.28) than in the <3 years category. On the other hand, among the participants who had a higher degree of psychological distress at the baseline, the proportion of those whose psychological distress ameliorated was significantly lower in the >4 years category (multivariate OR=0.26, 95% CI 0.06 to 0.85) than in the <3 years category. Conclusions The proportion of individuals with more severe psychological distress was higher among participants who had lived in prefabricated temporary housing for a long period. PMID:29730612

  4. Secondary Analysis of National Longitudinal Transition Study 2 Data

    ERIC Educational Resources Information Center

    Hicks, Tyler A.; Knollman, Greg A.

    2015-01-01

    This review examines published secondary analyses of National Longitudinal Transition Study 2 (NLTS2) data, with a primary focus upon statistical objectives, paradigms, inferences, and methods. Its primary purpose was to determine which statistical techniques have been common in secondary analyses of NLTS2 data. The review begins with an…

  5. Psychological Distress, Depression, Anxiety, and Burnout among International Humanitarian Aid Workers: A Longitudinal Study

    PubMed Central

    Lopes Cardozo, Barbara; Gotway Crawford, Carol; Eriksson, Cynthia; Zhu, Julia; Sabin, Miriam; Ager, Alastair; Foy, David; Snider, Leslie; Scholte, Willem; Kaiser, Reinhard; Olff, Miranda; Rijnen, Bas; Simon, Winnifred

    2012-01-01

    Background International humanitarian aid workers providing care in emergencies are subjected to numerous chronic and traumatic stressors. Objectives To examine consequences of such experiences on aid workers' mental health and how the impact is influenced by moderating variables. Methodology We conducted a longitudinal study in a sample of international non-governmental organizations. Study outcomes included anxiety, depression, burnout, and life and job satisfaction. We performed bivariate regression analyses at three time points. We fitted generalized estimating equation multivariable regression models for the longitudinal analyses. Results Study participants from 19 NGOs were assessed at three time points: 212 participated at pre-deployment; 169 (80%) post-deployment; and 154 (73%) within 3–6 months after deployment. Prior to deployment, 12 (3.8%) participants reported anxiety symptoms, compared to 20 (11.8%) at post-deployment (p = 0·0027); 22 (10.4%) reported depression symptoms, compared to 33 (19.5%) at post-deployment (p = 0·0117) and 31 (20.1%) at follow-up (p = .00083). History of mental illness (adjusted odds ratio [AOR] 4.2; 95% confidence interval [CI] 1·45–12·50) contributed to an increased risk for anxiety. The experience of extraordinary stress was a contributor to increased risk for burnout depersonalization (AOR 1.5; 95% CI 1.17–1.83). Higher levels of chronic stress exposure during deployment were contributors to an increased risk for depression (AOR 1·1; 95% CI 1·02–1.20) comparing post- versus pre-deployment, and increased risk for burnout emotional exhaustion (AOR 1.1; 95% CI 1.04–1.19). Social support was associated with lower levels of depression (AOR 0·9; 95% CI 0·84–0·95), psychological distress (AOR = 0.9; [CI] 0.85–0.97), burnout lack of personal accomplishment (AOR 0·95; 95% CI 0·91–0·98), and greater life satisfaction (p = 0.0213). Conclusions When recruiting and preparing aid workers for deployment, organizations should consider history of mental illness and take steps to decrease chronic stressors, and strengthen social support networks. PMID:22984592

  6. Association of consumption of fried food away from home with body mass index and diet quality in older children and adolescents.

    PubMed

    Taveras, Elsie M; Berkey, Catherine S; Rifas-Shiman, Sheryl L; Ludwig, David S; Rockett, Helaine R H; Field, Alison E; Colditz, Graham A; Gillman, Matthew W

    2005-10-01

    Rates of overweight have increased dramatically among children in the United States. Although an increase in consumption of food prepared away from home has paralleled overweight trends, few data exist relating food prepared away from home to change in BMI in children. The goals of this study were to (1) examine the cross-sectional and longitudinal associations between consumption of fried foods away from home (FFA) and BMI and (2) examine the cross-sectional associations between intake of FFA and several measures of diet quality. We studied a cohort of 7745 girls and 6610 boys, aged 9 to 14 years, at baseline in 1996. We obtained BMI from self-reported height and weight, measures of diet quality from a food frequency questionnaire, and weekly servings of FFA during the previous year. We performed linear regression analyses to assess the longitudinal associations between change in consumption of FFA on change in BMI, using data from three 1-year periods from 1996 through 1999. We also related consumption of FFA with intake of selected foods and nutrients at baseline. In cross-sectional analyses, adjusting for potential confounders, mean (SE) BMI was 19.1 (0.13) among children who ate FFA "never or <1/week," 19.2 (0.13) among those who responded "1 to 3 times/week," and 19.3 (0.18) among those who responded "4 to 7 times/week." In longitudinal multivariate models, increasing (over 1 year) consumption of FFA "never or <1/week" to "4 to 7/week" was associated with increasing BMI (beta = 0.21 kg/m2; 95% confidence interval: 0.03-0.39) compared with those with low consumption of FFA at baseline and 1 year later. At baseline, frequency of eating FFA was associated with greater intakes of total energy, sugar-sweetened beverages, and trans fat, as well as lower consumption of low-fat dairy foods and fruits and vegetables. These data suggest that older children who consume greater quantities of FFA are heavier, have greater total energy intakes, and have poorer diet quality. Furthermore, increasing consumption of FFA over time may lead to excess weight gain.

  7. Academic Performance of Language-Minority Students and All-Day Kindergarten: A Longitudinal Study

    ERIC Educational Resources Information Center

    Chang, Mido

    2012-01-01

    This longitudinal study examined the effect of all-day kindergarten programs on the academic achievement of students from racial language minority and low socioeconomic class. The study employed a series of 3-level longitudinal multilevel analyses using a nationally representative database, the Early Childhood Longitudinal Study (ECLS). The study…

  8. Longitudinal Association Between Human Parechovirus Central Nervous System Infection And Gross-motor Neurodevelopment in Young Children.

    PubMed

    van Hinsbergh, Ted M T; Elbers, Roy G; van Furth, Marceline A M; Obihara, Charlie C C

    2018-03-27

    A paucity of studies investigated the association between human parechovirus (HPeV) central nervous system (CNS) infection and motor and neurocognitive development of children. This study describes the gross-motor function (GMF) in young children during 24 months after HPeV-CNS-infection compared with children in whom no pathogen was detected. GMF of children was assessed with alberta infant motor scale, bayley scales of infant and toddler development or movement assessment battery for children. We conducted multivariate analyses and adjusted for age at onset, maternal education and time from infection. Of 91 included children, aged at onset <24 months, 11 had HPeV-CNS-infection and in 47 no pathogen was detected. Nineteen children were excluded due to the presence of other infection, preterm birth or genetic disorder and in 14 children parents refused to consent for participation. We found no longitudinal association between HPeV-CNS-infection and GMF (β = -0.53; 95%CI =-1.18 to 0.07; P = 0.11). At 6 months, children with HPeV-CNS-infection had suspect GMF delay compared with the non-pathogen group (mean difference = 1.12; 95%CI =-1.96 to -0.30; P = 0.03). This difference disappeared during 24 months follow-up and, after adjustment for age at onset, both groups scored within the normal range for age. Maternal education and time from infection did not have any meaningful influence. We found no longitudinal association between HPeV-CNS-infection and GMF during the first 24 months follow-up. Children with HPeV-CNS-infection showed a suspect GMF delay at 6 months follow-up. This normalized during 24 month follow-up.

  9. Knee Osteoarthritis and Risk of Hypertension: A Longitudinal Cohort Study.

    PubMed

    Veronese, Nicola; Stubbs, Brendon; Solmi, Marco; Smith, Toby O; Noale, Marianna; Schofield, Patricia; Maggi, Stefania

    2018-02-01

    Although previous research has indicated an association between osteoarthritis (OA) and cardiovascular disease, it remains unclear whether people with OA are at greater risk of developing hypertension. The aim of this study was to answer this uncertainity. We used the data of the Osteoarthritis Initiative, an ongoing public and private longitudinal study including people at higher risk of OA or having knee OA. Knee OA was defined through radiological and clinical assessment. Incident hypertension was defined as a systolic blood pressure ≥140 mmHg and/or a diastolic value ≥90 mmHg. Multivariate Cox's regression analyses were constructed considering the presence of knee OA as the exposure and incident hypertension as the outcome during a 96-month follow-up interval. A total of 3558 people with normative blood pressure values at baseline were analyzed (1930 OA/1628 controls). Incidence of hypertension within the follow-up interval was significantly higher in people with knee OA than in those without (60/[1000 person-years] vs. 55/[1000 person-years]; p < 0.0001). After adjusting for 13 confounders, people with knee OA had a 13% higher chance of developing hypertension (hazard ratio = 1.13; 95% confidence interval: 1.01-1.26; p = 0.03). Propensity score analysis did not alter these conclusions. In conclusion, this is the first longitudinal data analysis to demonstrate that people with knee OA have a higher chance of developing hypertension than those without OA. Our data suggest that monitoring blood pressure and prescribing health promotion interventions may be warranted among people with OA to mitigate the potential onset and adverse consequences of hypertension.

  10. Risk of malignancy with systemic psoriasis treatment in the Psoriasis Longitudinal Assessment Registry.

    PubMed

    Fiorentino, David; Ho, Vincent; Lebwohl, Mark G; Leite, Luiz; Hopkins, Lori; Galindo, Claudia; Goyal, Kavitha; Langholff, Wayne; Fakharzadeh, Steven; Srivastava, Bhaskar; Langley, Richard G

    2017-11-01

    The effect of systemic therapy on malignancy risk among patients with psoriasis is not fully understood. Evaluate the impact of systemic treatment on malignancy risk among patients with psoriasis in the Psoriasis Longitudinal Assessment and Registry (PSOLAR). Nested case-control analyses were performed among patients with no history of malignancy. Cases were defined as first malignancy (other than nonmelanoma skin cancer) in the Psoriasis Longitudinal Assessment and Registry, and controls were matched by age, sex, geographic region, and time on registry. Study therapies included methotrexate, ustekinumab, and tumor necrosis factor-α (TNF-α) inhibitors. Exposure was defined as 1 or more doses of study therapy within 12 months of malignancy onset and further stratified by duration of therapy. Multivariate conditional logistic regression, adjusted for potential confounders, was used to estimate odds ratios of malignancies associated with therapy. Among 12,090 patients, 252 malignancy cases were identified and 1008 controls were matched. Treatment with methotrexate or ustekinumab for more than 0 months to less than 3 months, 3 months to less than 12 months, or 12 months or longer was not associated with increased malignancy risk versus no exposure. Longer-term (≥12 months) (odds ratio, 1.54; 95% confidence interval, 1.10-2.15; P = .01), but not shorter-term treatment, with a TNF-α inhibitor was associated with increased malignancy risk. Cases and controls could belong to 1 or more therapy categories. Long-term (≥12 months) treatment with a TNF-α inhibitor, but not methotrexate and ustekinumab, may increase risk for malignancy in patients with psoriasis. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  11. Early childhood trajectories of separation anxiety: Bearing on mental health, academic achievement, and physical health from mid-childhood to preadolescence.

    PubMed

    Battaglia, Marco; Garon-Carrier, Gabrielle; Côté, Sylvana M; Dionne, Ginette; Touchette, Evelyne; Vitaro, Frank; Tremblay, Richard E; Boivin, Michel

    2017-10-01

    Separation anxiety disorder is the most prevalent childhood anxiety condition, but no study assessed children for separation anxiety at preschool age and followed them longitudinally and directly until mid-childhood/early adolescence. Multi-informant (children, teachers, family), multipoint (at age 8, 10, 12, 13) assessments of 1,290 children of the Quebec Longitudinal Study of Child Development, who had been categorized between age 1.5 and 6 into four specific separation anxiety trajectories (1, low-persistent; 2, low-increasing; 3, high-decreasing, and the less common: 4, high-increasing) by growth mixture modeling. Participants in the high-increasing trajectory were compared to participants in the other three trajectories for: (a) child's internalizing and externalizing problem behavior; (b) physical health; (c) academic achievement; (d) maternal anxiety. Multivariate analyses of variance/covariance at separate time points showed the high-increasing trajectory mostly associated with: (a) higher internalizing, but not externalizing, behavior; (b) worse academic achievement (most consistently by comparisons to the normative low-persistent trajectory; (c) higher rates of maternal panic/agoraphobic anxiety; (d) worse physical health (most consistently by comparisons to the low-persistent trajectory). The high-increasing trajectory had twofold to threefold higher incidences of physical illnesses than the normative low-persistent group; this was specific for headaches at age 12 years, chronic asthma at age 10 and 13, and having received asthma-related medication during the past 12 months. High-increasing separation anxiety in preschool maintains longitudinal relationships to independent health and academic outcomes, at least until preadolescence. This knowledge can inform the deployment of clinical resources at the earlier signs of the more impairing manifestations. © 2017 Wiley Periodicals, Inc.

  12. Body mass index gain between ages 20-40 years and lifestyle characteristics of men at ages 40-60 years: The Adventist Health Study-2

    PubMed Central

    Japas, Claudio; Knutsen, Synnøve; Dehom, Salem; Dos Santos, Hildemar; Tonstad, Serena

    2014-01-01

    Background Obesity increases risk of premature disease, and may be associated with unfavorable lifestyle changes that add to risk. This study analyzed the association of midlife BMI change with current lifestyle patterns among multiethnic men. Methods Men aged 40-60 years (n=9864) retrospectively reported body weight between ages 20-40 years and current dietary, TV, physical activity and sleep practices in the Adventist Health Study II, a study of church-goers in the US and Canada. In multivariate logistic regression analysis, odds ratios for BMI gain were calculated for each lifestyle practice controlling for sociodemographic and other lifestyle factors and current BMI. Results Men with median or higher BMI gain (2.79 kg/m2) between ages 20-40 years were more likely to consume a non-vegetarian diet, and engage in excessive TV watching and little physical activity and had a shorter sleep duration compared to men with BMI gain below the median (all p<0.001). In multivariate logistic analysis current BMI was significantly associated with all lifestyle factors in multivariate analyses (all p≤0.005). BMI gain was associated with lower odds of vegetarian diet (odds ratio [OR] 0.939; 95% confidence interval [CI] 0.921-0.957) and of physical activity ≥150 minutes/week (OR 0.979, 95% CI 0.960-0.999). Conclusions These findings imply that diet and less physical activity are associated with both gained and attained BMI, while inactivity (TV watching) and short sleep duration correlated only with attained BMI. Unhealthy lifestyle may add risk to that associated with BMI. Longitudinal and intervention studies are needed to infer causal relationships. PMID:25434910

  13. Sick of our loans: Student borrowing and the mental health of young adults in the United States.

    PubMed

    Walsemann, Katrina M; Gee, Gilbert C; Gentile, Danielle

    2015-01-01

    Student loans are increasingly important and commonplace, especially among recent cohorts of young adults in the United States. These loans facilitate the acquisition of human capital in the form of education, but may also lead to stress and worries related to repayment. This study investigated two questions: 1) what is the association between the cumulative amount of student loans borrowed over the course of schooling and psychological functioning when individuals are 25-31 years old; and 2) what is the association between annual student loan borrowing and psychological functioning among currently enrolled college students? We also examined whether these relationships varied by parental wealth, college enrollment history (e.g. 2-year versus 4-year college), and educational attainment (for cumulative student loans only). We analyzed data from the National Longitudinal Survey of Youth 1997 (NLSY97), a nationally representative sample of young adults in the United States. Analyses employed multivariate linear regression and within-person fixed-effects models. Student loans were associated with poorer psychological functioning, adjusting for covariates, in both the multivariate linear regression and the within-person fixed effects models. This association varied by level of parental wealth in the multivariate linear regression models only, and did not vary by college enrollment history or educational attainment. The present findings raise novel questions for further research regarding student loan debt and the possible spillover effects on other life circumstances, such as occupational trajectories and health inequities. The study of student loans is even more timely and significant given the ongoing rise in the costs of higher education. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Association of Low-Grade Albuminuria with Adverse Cardiac Mechanics: Findings from the HyperGEN Study

    PubMed Central

    Katz, Daniel H.; Selvaraj, Senthil; Aguilar, Frank G.; Martinez, Eva E.; Beussink, Lauren; Kim, Kwang-Youn A.; Peng, Jie; Sha, Jin; Irvin, Marguerite R.; Eckfeldt, John H.; Turner, Stephen T.; Freedman, Barry I.; Arnett, Donna K.; Shah, Sanjiv J.

    2013-01-01

    Introduction Albuminuria is a marker of endothelial dysfunction and has been associated with adverse cardiovascular outcomes. The reasons for this association are unclear, but may be due to the relationship between endothelial dysfunction and intrinsic myocardial dysfunction. Methods and Results In the HyperGEN study, a population- and family-based study of hypertension, we examined the relationship between urine albumin-to-creatinine ratio (UACR) and cardiac mechanics (N=1894, all of whom had normal left ventricular ejection fraction and wall motion). We performed speckle-tracking echocardiographic analysis to quantify global longitudinal, circumferential, and radial strain (GLS, GCS, and GRS, respectively), and early diastolic (e′) tissue velocities. We used E/e′ ratio as a marker of increased LV filling pressures. We used multivariable-adjusted linear mixed effect models to determine independent associations between UACR and cardiac mechanics. The mean age was 50±14 years, 59% were female, and 46% were African-American. Comorbidities were increasingly prevalent among higher UACR quartiles. Albuminuria was associated with GLS, GCS, GRS, e′ velocity, and E/e′ ratio on unadjusted analyses. After adjustment for covariates, UACR was independently associated with lower absolute GLS (multivariable-adjusted mean GLS [95% CI] for UACR Quartile 1 = 15.3 [15.0–15.5]% vs. UACR Q4 = 14.6 [14.3–14.9]%, P for trend <0.001) and increased E/e′ ratio (Q1 = 25.3 [23.5–27.1] vs. Q4 = 29.0 [27.0–31.0], P= 0.003). The association between UACR and GLS was present even in participants with UACR < 30 mg/g (P<0.001 after multivariable adjustment). Conclusions Albuminuria, even at low levels, is associated with adverse cardiac mechanics and higher E/e′ ratio. PMID:24077169

  15. Dynamics of Volunteering in Older Europeans

    ERIC Educational Resources Information Center

    Hank, Karsten; Erlinghagen, Marcel

    2010-01-01

    Purpose: To investigate the dynamics of volunteering in the population aged 50 years or older across 11 Continental European countries. Design and Methods: Using longitudinal data from the first 2 waves of the Survey of Health, Ageing and Retirement in Europe, we run multivariate regressions on a set of binary-dependent variables indicating…

  16. Advertisement and knowledge of tobacco products among Ellisras rural children aged 11 to 18 years: Ellisras Longitudinal study

    PubMed Central

    2013-01-01

    Background Tobacco products use is the leading cause of chronic diseases morbidity and mortality. This study explores an exposure to tobacco advertisements factors and knowledge, an association with snuff/pipe usage and cigarette smoking among Ellisras rural children aged between 11 to 18 years. Methods A total of 1654 subjects (854 boys and 800 girls) who were part of the Ellisras Longitudinal Study completed the questionnaire. Results A significant (p < 0.05) number of boys (11.7%) compared to girls (8.8%) received free cigarettes from the members of the community. Bill boards were successful in advertising tobacco products among the Ellisras rural boys (17% boys and 12.8% for girls, p < 0.022). Multivariate analyses found significant association between cigarette smoking (OR = 1.7 95%CI 1.1-2.7 and Model 2 OR 1.6 95%CI 1.0-2.6 adjusted for age and gender) and advertisements of tobacco products on the TV screens, videos or movies. Conclusions Exposure to tobacco products advertisements was high among Ellisras rural children. Though tobacco products legislation exists in South Africa, efforts should be taken by the health professionals to emphasize the danger of using tobacco products even among the illiterate. Teachers and parents should refrain from advertising tobacco products at schools and at homes. PMID:23914793

  17. Trends in antibiotic resistance over time among pathogens from Canadian hospitals: results of the CANWARD study 2007-11.

    PubMed

    Lagacé-Wiens, Philippe R S; Adam, Heather J; Low, Donald E; Blondeau, Joseph M; Baxter, Melanie R; Denisuik, Andrew J; Nichol, Kimberly A; Walkty, Andrew; Karlowsky, James A; Mulvey, Michael R; Hoban, Daryl J; Zhanel, George G

    2013-05-01

    Antimicrobial resistance patterns change over time and longitudinal surveillance studies provide insight into these trends. We sought to describe the important trends in antimicrobial resistance in key pathogens across Canada to provide useful information to clinicians, policy makers and industry, to assist in optimizing antimicrobial therapy, formulary choices and drug development. We analysed longitudinal data from the CANWARD study using a multivariate regression model to control for possible effects of patient demographics on resistance, in order to assess the impact of time on antimicrobial resistance independent of other measured variables. We identified several key trends in common pathogens. In particular, we observed a statistically significant increase in the proportion of Escherichia coli isolates that were resistant to extended-spectrum cephalosporins and fluoroquinolones, an increase in the proportion of Klebsiella pneumoniae isolates that were resistant to extended-spectrum cephalosporins, a reduction in the proportion of Staphylococcus aureus that were methicillin, clindamycin and trimethoprim/sulfamethoxazole resistant, and a reduction in the proportion of Pseudomonas aeruginosa that were fluoroquinolone and gentamicin resistant. Although some of these trends, such as the dramatic increase in fluoroquinolone and cephalosporin resistance in E. coli, can be attributed to the emergence and global spread of resistant clones (e.g. ST131 E. coli), others remain unexplained. However, recognizing these trends remains important to guide changes in empirical antimicrobial therapy and drug development.

  18. Understanding the Role of Conscientiousness in Healthy Aging: Where Does the Brain Come In?

    PubMed Central

    Patrick, Christopher J.

    2014-01-01

    In reviewing this impressive series of articles, I was struck by two points in particular: (1) the fact that the empirically-oriented articles focused on analyses of data from very large samples, with the two papers by Friedman and colleagues highlighting an approach to merging existing datasets through use of “metric bridges” in order to address key questions not addressable through one dataset alone, and (2) the fact that the articles as a whole included limited mention of neuroscientific (i.e., brain research) concepts, methods, and findings. One likely reason for the lack of reference to brain-oriented work is the persisting gap between smaller-N lab-experimental and larger-N multivariate-correlational approaches to psychological research. As a strategy for addressing this gap and bringing a distinct neuroscientific component to the National Institute on Aging’s conscientiousness and health initiative, I suggest that the metric bridging approach highlighted by Friedman and colleagues could be used to connect existing large-scale datasets containing both neurophysiological variables and measures of individual difference constructs to other datasets containing richer arrays of non-physiological variables—including data from longitudinal or twin studies focusing on personality and health-related outcomes (e.g., Terman Life Cycle study and Hawaii longitudinal studies, as described in the article by Kern et al.). PMID:24773108

  19. The child protection and juvenile justice nexus in Australia: A longitudinal examination of the relationship between maltreatment and offending.

    PubMed

    Malvaso, Catia G; Delfabbro, Paul H; Day, Andrew

    2017-02-01

    There is convincing evidence that many young people who are in the justice system have had contact with child protection services and that victims of childhood maltreatment are at increased risk of subsequent youth justice involvement. In Australia, however, there have been few longitudinal studies that have examined these associations and relatively less is known in this area. This study examines the overlap between the child protection and youth justice involvement in South Australia, and determines how substantiated maltreatment and variations in these experiences (e.g., the type, timing and recurrence of maltreatment) relate to criminal convictions as a youth. The results show that although the majority of child-protection involved youth do not become convicted offenders, the odds of subsequent convictions are significantly greater both for those with notifications and substantiated maltreatment and for those who had been placed in out-of-home care. Multivariate analyses revealed that the strongest predictors for receiving a conviction among maltreated youth were: male gender, Aboriginal and Torres Strait Islander ethnicity, experiences of physical abuse and emotional abuse, a greater number of substantiations (recurrence), experiencing maltreatment that commenced in childhood and continued into adolescence, and placement in out-of-home care. The mechanisms through which maltreatment might be linked with behavior are then considered, along with directions for future research in this area. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Longitudinal Influences of Neighbourhood Built and Social Environment on Children’s Weight Status

    PubMed Central

    Gose, Maria; Plachta-Danielzik, Sandra; Willié, Bianca; Johannsen, Maike; Landsberg, Beate; Müller, Manfred J.

    2013-01-01

    The objective was to examine longitudinal 4-year-relationships between neighbourhood social environment and children’s body mass index-standard deviation score (BMI-SDS) taking into account the built environment. Furthermore, we have analysed the influence of potential interactions between the social environment and family/social data on children’s BMI-SDS. Between 2006–2008 and 2010–2012, anthropometric measurements were conducted among 485 children (age at baseline: 6.1 (5.8–6.4)). Socio-demographic characteristics and perception of residential environment were reported by parents. Geographic Information Systems were used to examine street length, number of food outlets and distance to the nearest playground and park/green space within an 800 m Euclidian buffer of each participant address point. Additional data on neighbourhood characteristics (e.g., traffic density, walkability, crime rates) were obtained from the State Capital of Kiel, Germany. In a multivariate model, walkability, street type, socioeconomic status of the district and perceived frequency of passing trucks/busses were associated with BMI-SDS over 4 years, but only neighbourhood SES had an effect on change in BMI-SDS. However, familial/social factors rather than neighbourhood environment (especially social environment) had an impact on children’s BMI-SDS over 4 years. Thus, social inequalities in childhood overweight are only partially explained by social neighbourhood environment. PMID:24132135

  1. Clinical associations of anti-Smith antibodies in PROFILE: a multi-ethnic lupus cohort.

    PubMed

    Arroyo-Ávila, Mariangelí; Santiago-Casas, Yesenia; McGwin, Gerald; Cantor, Ryan S; Petri, Michelle; Ramsey-Goldman, Rosalind; Reveille, John D; Kimberly, Robert P; Alarcón, Graciela S; Vilá, Luis M; Brown, Elizabeth E

    2015-07-01

    The aim of this study was to determine the association of anti-Sm antibodies with clinical manifestations, comorbidities, and disease damage in a large multi-ethnic SLE cohort. SLE patients (per American College of Rheumatology criteria), age ≥16 years, disease duration ≤10 years at enrollment, and defined ethnicity (African American, Hispanic or Caucasian), from a longitudinal US cohort were studied. Socioeconomic-demographic features, cumulative clinical manifestations, comorbidities, and disease damage (as per the Systemic Lupus International Collaborating Clinics Damage Index [SDI]) were determined. The association of anti-Sm antibodies with clinical features was examined using multivariable logistic regression analyses adjusting for age, gender, ethnicity, disease duration, level of education, health insurance, and smoking. A total of 2322 SLE patients were studied. The mean (standard deviation, SD) age at diagnosis was 34.4 (12.8) years and the mean (SD) disease duration was 9.0 (7.9) years; 2127 (91.6%) were women. Anti-Sm antibodies were present in 579 (24.9%) patients. In the multivariable analysis, anti-Sm antibodies were significantly associated with serositis, renal involvement, psychosis, vasculitis, Raynaud's phenomenon, hemolytic anemia, leukopenia, lymphopenia, and arterial hypertension. No significant association was found for damage accrual. In this cohort of SLE patients, anti-Sm antibodies were associated with several clinical features including serious manifestations such as renal, neurologic, and hematologic disorders as well as vasculitis.

  2. Satisfaction with care: a study of parents of children with congenital heart disease and parents of children with other diseases.

    PubMed

    Lawoko, Stephen; Soares, Joaquim J F

    2004-03-01

    We compared parents of children with congenital heart disease (PCCHD, n=1092) with parents of children with other diseases (PCOD, n=112) regarding satisfaction with their children's care (SCC). We also examined the association between parental/patient characteristics and SCC. The parents completed a questionnaire about such areas as satisfaction with care, children's health status, and financial situation. The design was cross-sectional and data were gathered over 20 consecutive days. The univariate and multivariate analyses showed that PCCHD were more satisfied with their children's medical care and waiting period for treatment of their ill children than PCOD, although the difference was only modest. Furthermore, mothers were less satisfied with staff attitudes than fathers, with the lowest satisfaction among mothers of children with CHD. However, the multivariate analysis indicated that less satisfaction with care was more associated with decreasing child age, unemployment, financial burden of disease, social isolation and psychological distress than with children's diseases, their severity and parental gender. We corroborated some previous findings and may have provided new insights regarding determinants of SCC among parents. Interventions to improve SCC may need to address issues of parental psychological distress, socialization, and financial burden of illness. Possible ways of achieving this are discussed. Finally, research in a longitudinal format is needed to further scrutinize determinants of parental SCC.

  3. Aboriginal Street-involved Youth Experience Elevated Risk of Incarceration

    PubMed Central

    Barker, Brittany; Alfred, Gerald Taiaiake; Fleming, Kim; Nguyen, Paul; Wood, Evan; Kerr, Thomas; DeBeck, Kora

    2015-01-01

    Objectives Past research has identified risk factors associated with incarceration among adult Aboriginal populations; however, less is known about incarceration among street-involved Aboriginal youth. Therefore, we undertook this study to longitudinally investigate recent reports of incarceration among a prospective cohort of street-involved youth in Vancouver, Canada. Study Design Prospective cohort study. Methods Data were collected from a cohort of street-involved, drug-using youth from September 2005 to May 2013. Multivariate generalized estimating equation analyses were employed to examine the potential relationship between Aboriginal ancestry and recent incarceration. Results Among our sample of 1050 youth, 248 (24%) reported being of aboriginal ancestry, and 378 (36%) reported being incarcerated in the previous six months at some point during the study period. In multivariate analysis controlling for a range of potential confounders including drug use patterns and other risk factors, Aboriginal ancestry remained significantly associated with recent incarceration (adjusted odds ratio [AOR]=1.44; 95% confidence interval [CI]: 1.12–1.86). Conclusions Even after adjusting for drug use patterns and other risk factors associated with incarceration, this study found that Aboriginal street-involved youth were still significantly more likely to be incarcerated than their non-Aboriginal peers. Given the established harms associated with incarceration these findings underscore the pressing need for systematic reform including culturally appropriate interventions to prevent Aboriginal youth from becoming involved with the criminal justice system. PMID:26390949

  4. Designs and Methods in School Improvement Research: A Systematic Review

    ERIC Educational Resources Information Center

    Feldhoff, Tobias; Radisch, Falk; Bischof, Linda Marie

    2016-01-01

    Purpose: The purpose of this paper is to focus on challenges faced by longitudinal quantitative analyses of school improvement processes and offers a systematic literature review of current papers that use longitudinal analyses. In this context, the authors assessed designs and methods that are used to analyze the relation between school…

  5. Use of Multivariate Linkage Analysis for Dissection of a Complex Cognitive Trait

    PubMed Central

    Marlow, Angela J.; Fisher, Simon E.; Francks, Clyde; MacPhie, I. Laurence; Cherny, Stacey S.; Richardson, Alex J.; Talcott, Joel B.; Stein, John F.; Monaco, Anthony P.; Cardon, Lon R.

    2003-01-01

    Replication of linkage results for complex traits has been exceedingly difficult, owing in part to the inability to measure the precise underlying phenotype, small sample sizes, genetic heterogeneity, and statistical methods employed in analysis. Often, in any particular study, multiple correlated traits have been collected, yet these have been analyzed independently or, at most, in bivariate analyses. Theoretical arguments suggest that full multivariate analysis of all available traits should offer more power to detect linkage; however, this has not yet been evaluated on a genomewide scale. Here, we conduct multivariate genomewide analyses of quantitative-trait loci that influence reading- and language-related measures in families affected with developmental dyslexia. The results of these analyses are substantially clearer than those of previous univariate analyses of the same data set, helping to resolve a number of key issues. These outcomes highlight the relevance of multivariate analysis for complex disorders for dissection of linkage results in correlated traits. The approach employed here may aid positional cloning of susceptibility genes in a wide spectrum of complex traits. PMID:12587094

  6. Longitudinal patterns of semantic and episodic memory in frontotemporal lobar degeneration and Alzheimer's disease.

    PubMed

    Xie, Sharon X; Libon, David J; Wang, Xingmei; Massimo, Lauren; Moore, Peachie; Vesely, Luisa; Khan, Alea; Chatterjee, Anjan; Coslett, H Branch; Hurtig, Howard I; Liang, Tsao-Wei; Grossman, Murray

    2010-03-01

    The longitudinal assessment of episodic and semantic memory was obtained from 236 patients diagnosed with Alzheimer's disease (AD, n = 128) and with frontotemporal lobar degeneration (FTLD, n = 108), including patients with a social comportment/dysexecutive (SOC/EXEC) disorder, progressive nonfluent aphasia (PNFA), semantic dementia (SemD), and corticobasal syndrome (CBS). At the initial assessment, AD patients obtained a lower score on the delayed free recall test than other patients. Longitudinal analyses for delayed free recall found converging performance, with all patients reaching the same level of impairment as AD patients. On the initial evaluation for delayed recognition, AD patients also obtained lower scores than other groups. Longitudinal analyses for delayed recognition test performance found that AD patients consistently produced lower scores than other groups and no convergence between AD and other dementia groups was seen. For semantic memory, there were no initial between-group differences. However, longitudinal analyses for semantic memory revealed group differences over illness duration, with worse performance for SemD versus AD, PNFA, SOC/EXEC, and CBS patients. These data suggest the presence of specific longitudinal patterns of impairment for episodic and semantic memory in AD and FTLD patients suggesting that all forms of dementia do not necessarily converge into a single phenotype.

  7. Risk factors for low receptive vocabulary abilities in the preschool and early school years in the longitudinal study of Australian children.

    PubMed

    Christensen, Daniel; Zubrick, Stephen R; Lawrence, David; Mitrou, Francis; Taylor, Catherine L

    2014-01-01

    Receptive vocabulary development is a component of the human language system that emerges in the first year of life and is characterised by onward expansion throughout life. Beginning in infancy, children's receptive vocabulary knowledge builds the foundation for oral language and reading skills. The foundations for success at school are built early, hence the public health policy focus on reducing developmental inequalities before children start formal school. The underlying assumption is that children's development is stable, and therefore predictable, over time. This study investigated this assumption in relation to children's receptive vocabulary ability. We investigated the extent to which low receptive vocabulary ability at 4 years was associated with low receptive vocabulary ability at 8 years, and the predictive utility of a multivariate model that included child, maternal and family risk factors measured at 4 years. The study sample comprised 3,847 children from the first nationally representative Longitudinal Study of Australian Children (LSAC). Multivariate logistic regression was used to investigate risks for low receptive vocabulary ability from 4-8 years and sensitivity-specificity analysis was used to examine the predictive utility of the multivariate model. In the multivariate model, substantial risk factors for receptive vocabulary delay from 4-8 years, in order of descending magnitude, were low receptive vocabulary ability at 4 years, low maternal education, and low school readiness. Moderate risk factors, in order of descending magnitude, were low maternal parenting consistency, socio-economic area disadvantage, low temperamental persistence, and NESB status. The following risk factors were not significant: One or more siblings, low family income, not reading to the child, high maternal work hours, and Aboriginal or Torres Strait Islander ethnicity. The results of the sensitivity-specificity analysis showed that a well-fitted multivariate model featuring risks of substantive magnitude does not do particularly well in predicting low receptive vocabulary ability from 4-8 years.

  8. Genetic and Environmental Influences on Language Ability in Older Adults: Findings from the Older Australian Twins Study.

    PubMed

    Lee, T; Thalamuthu, A; Henry, J D; Trollor, J N; Ames, D; Wright, M J; Sachdev, P S

    2018-05-01

    We used a sub-sample from the Older Australian Twins Study to estimate the heritability of performance on three tests of language ability: Boston Naming Test (BNT), Letter/Phonemic Fluency (FAS) and Category/Semantic Fluency (CFT) Tests. After adjusting for age, sex, education, mood, and global cognition (GC), heritability estimates obtained for the three tests were 0.35, 0.59, and 0.20, respectively. Multivariate analyses showed that the genetic correlation were high for BNT and CFT (0.61), but low for BNT and FAS (0.17), and for FAS and CFT (0.28). Genetic modelling with Cholesky decomposition indicated that the covariation between the three measures could be explained by a common genetic factor. Environmental correlations between the language ability measures were low, and there were considerable specific environmental influences for each measure. Future longitudinal studies with language performance and neuroimaging data can further our understanding of genetic and environmental factors involved in the process of cognitive aging.

  9. Characteristics of Child Maltreatment and Adolescent Marijuana Use: A Prospective Study.

    PubMed

    Dubowitz, Howard; Thompson, Richard; Arria, Amelia M; English, Diana; Metzger, Richard; Kotch, Jonathan B

    2016-02-01

    There has been increasing acceptance of marijuana use in the United States in recent years, and rates among adolescents have risen. At the same time, marijuana use during adolescence has been linked to an array of health and social problems. Maltreated children are at risk for marijuana use, but the relationships among characteristics of maltreatment and marijuana use are unclear. In this article, we examine how the type and the extent of maltreatment are related to the level of adolescent marijuana use. Data analyses were conducted on a subsample of maltreated adolescents (n = 702) from the Longitudinal Studies of Child Abuse and Neglect project. Approximately half the sample had used marijuana, and maltreatment was associated with its use. Multivariate regression models showed that being male, extensive maltreatment, and peer marijuana use were associated with heavy use of marijuana. These findings suggest the importance of comprehensively assessing children's maltreatment experiences and their peers' drug use to help prevent or address possible marijuana use in these high-risk adolescents. © The Author(s) 2015.

  10. Work stress, sleep deficiency and predicted 10-year cardiometabolic risk in a female patient care worker population

    PubMed Central

    Jacobsen, Henrik Børsting; Reme, Silje Endresen; Sembajwe, Grace; Hopcia, Karen; Stiles, Tore C.; Sorensen, Glorian; Porter, James H.; Marino, Miguel; Buxton, Orfeu M.

    2014-01-01

    Objectives The aim of this study was to investigate the longitudinal effect of work-related stress, sleep deficiency and physical activity on 10-year cardiometabolic risk among an all-female worker population. Methods Data on patient care workers (n=99) was collected two years apart. Baseline measures included: job stress, physical activity, night work and sleep deficiency. Biomarkers and objective measurements were used to estimate 10-year cardiometabolic risk at follow-up. Significant associations (P<0.05) from baseline analyses were used to build a multivariable linear regression model. Results The participants were mostly white nurses with a mean age of 41 years. Adjusted linear regression showed that having sleep maintenance problems, a different occupation than nurse, and/or not exercising at recommended levels at baseline increased the 10-year cardiometabolic risk at follow-up. Conclusions In female workers prone to work-related stress and sleep deficiency, maintaining sleep and exercise patterns had a strong impact on modifiable 10-year cardiometabolic risk. PMID:24809311

  11. Characteristics of Child Maltreatment and Adolescent Marijuana Use: A Prospective Study

    PubMed Central

    Dubowitz, Howard; Thompson, Richard; Arria, Amelia M.; English, Diana; Metzger, Richard; Kotch, Jonathan B.

    2015-01-01

    There has been increasing acceptance of marijuana use in the US in recent years, and rates among adolescents have risen. At the same time, marijuana use during adolescence has been linked to an array of health and social problems. Maltreated children are at risk for marijuana use, but the relationships among characteristics of maltreatment and marijuana use are unclear. In this paper we examine how the type and the extent of maltreatment are related to the level of adolescent marijuana use. Data analyses were conducted on a subsample of maltreated adolescents (n = 702) from the Longitudinal Studies of Child Abuse and Neglect (LONGSCAN) project. Approximately half the sample had used marijuana, and maltreatment was associated with its use. Multivariate regression models showed that being male, extensive maltreatment, and peer marijuana use were associated with Heavy Use of marijuana. These findings suggest the importance of comprehensively assessing children’s maltreatment experiences and their peers’ drug use to help prevent or address possible marijuana use in these high-risk adolescents. PMID:26715532

  12. Do adult emotional and behavioural outcomes vary as a function of diverse childhood experiences of the public care system?

    PubMed

    Dregan, A; Brown, J; Armstrong, D

    2011-10-01

    Longitudinal data from the 1970 British Cohort Study were used to examine the long-term adult outcomes of those who, as children, were placed in public care. Multivariate logistic estimation models were used to determine whether public care and placement patterns were associated with adult psychosocial outcomes. Seven emotional and behavioural outcomes measured at age 30 years were considered: depression, life dissatisfaction, self-efficacy, alcohol problems, smoking, drug abuse, and criminal convictions. The analyses revealed a significant association between public care status and adult maladjustment on depression [odds ratio (OR) 1.74], life dissatisfaction (OR 1.45), low self-efficacy (OR 1.95), smoking (OR 1.70) and criminal convictions (OR 2.13). Overall, the present study findings suggest that there are enduring influences of a childhood admission to public care on emotional and behavioural adjustment from birth to adulthood. Some of the associations with childhood public care were relatively strong, particularly with respect to depression, self-efficacy and criminal convictions.

  13. Work stress, sleep deficiency, and predicted 10-year cardiometabolic risk in a female patient care worker population.

    PubMed

    Jacobsen, Henrik B; Reme, Silje E; Sembajwe, Grace; Hopcia, Karen; Stiles, Tore C; Sorensen, Glorian; Porter, James H; Marino, Miguel; Buxton, Orfeu M

    2014-08-01

    The aim of this study was to investigate the longitudinal effect of work-related stress, sleep deficiency, and physical activity on 10-year cardiometabolic risk among an all-female worker population. Data on patient care workers (n=99) was collected 2 years apart. Baseline measures included: job stress, physical activity, night work, and sleep deficiency. Biomarkers and objective measurements were used to estimate 10-year cardiometabolic risk at follow-up. Significant associations (P<0.05) from baseline analyses were used to build a multivariable linear regression model. The participants were mostly white nurses with a mean age of 41 years. Adjusted linear regression showed that having sleep maintenance problems, a different occupation than nurse, and/or not exercising at recommended levels at baseline increased the 10-year cardiometabolic risk at follow-up. In female workers prone to work-related stress and sleep deficiency, maintaining sleep and exercise patterns had a strong impact on modifiable 10-year cardiometabolic risk. © 2014 Wiley Periodicals, Inc.

  14. The Multivariate Roles of Family Instability and Interparental Conflict in Predicting Children's Representations of Insecurity in the Family System and Early School Adjustment Problems.

    PubMed

    Coe, Jesse L; Davies, Patrick T; Sturge-Apple, Melissa L

    2017-02-01

    This study examined the moderating role of family instability in relations involving destructive interparental conflict, children's internal representations of insecurity in the family system, and their early school maladjustment. Two hundred forty-three preschool children (M age = 4.60 years; 56 % girls) and their families participated in this multi-method (i.e., observations, structured interview, surveys) multi-informant (i.e., observer, parent, teacher), longitudinal study. Findings indicated that the mediational role of children's insecure family representations in the pathway between destructive interparental conflict and children's adjustment problems varied significantly depending on the level of family instability. Interparental conflict was specifically associated with insecure family representations only under conditions of low family instability. In supporting the role of family instability as a vulnerable-stable risk factor, follow up analyses revealed that children's concerns about security in the family were uniformly high under conditions of heightened instability regardless of their level of exposure to interparental conflict.

  15. The contribution of work engagement to self-perceived health, work ability, and sickness absence beyond health behaviors and work-related factors.

    PubMed

    Rongen, Anne; Robroek, Suzan J W; Schaufeli, Wilmar; Burdorf, Alex

    2014-08-01

    To investigate whether work engagement influences self-perceived health, work ability, and sickness absence beyond health behaviors and work-related characteristics. Employees of two organizations participated in a 6-month longitudinal study (n = 733). Using questionnaires, information was collected on health behaviors, work-related characteristics, and work engagement at baseline, and self-perceived health, work ability, and sickness absence at 6-month follow-up. Associations between baseline and follow-up variables were studied using multivariate and multinomial logistic regression analyses and changes in R2 were calculated. Low work engagement was related with low work ability (odds ratio: 3.68; 95% confidence interval: 2.15 to 6.30) and long-term sickness absence (odds ratio: 1.84; 95% confidence interval: 1.04 to 3.27). Work engagement increased the explained variance in work ability and sickness absence with 4.1% and 0.5%, respectively. Work engagement contributes to work ability beyond known health behaviors and work-related characteristics.

  16. PREVALENCE AND PSYCHOSOCIAL CORRELATES OF ALCOHOL-RELATED SEXUAL ASSAULT AMONG UNIVERSITY STUDENTS

    PubMed Central

    Howard, Donna E.; Griffin, Melinda A.; Boekeloo, Bradley O.

    2009-01-01

    This study examined the psychosocial correlates of alcohol-related sexual assault. Undergraduate students (N = 551) were recruited to complete a web-based survey. The outcome was a composite of 2 items: “experienced an unwanted sexual advance” or “was the victim of sexual assault or date rape” as a result of another’s alcohol use. The predictors were substance use, other alcohol-related interpersonal violence victimization, and alcohol-related protective behaviors. Multivariate logistic regression analyses were conducted. Females reported higher prevalence of alcohol-related sexual assault than did males (20.4% vs. 6.6%). Females who reported binge drinking (OR = 7.74) and other alcohol-related interpersonal violence (OR = 5.03) were more likely to report alcohol-related sexual assault whereas only other alcohol-related interpersonal violence was associated with alcohol-related sexual assault (OR = 43.75) among males. The findings suggest that alcohol-related sexual assault is associated with other risk factors that deserve further attention through longitudinal research and intervention efforts. PMID:19149143

  17. Prevalence and psychosocial correlates of alcohol-related sexual assault among university students.

    PubMed

    Howard, Donna E; Griffin, Melinda A; Boekeloo, Bradley O

    2008-01-01

    This study examined the psychosocial correlates of alcohol-related sexual assault. Undergraduate students (N = 551) were recruited to complete a web-based survey. The outcome was a composite of 2 items: "experienced an unwanted sexual advance" or "was the victim of sexual assault or date rape" as a result of another's alcohol use. The predictors were substance use, other alcohol-related interpersonal violence victimization, and alcohol-related protective behaviors. Multivariate logistic regression analyses were conducted. Females reported higher prevalence of alcohol-related sexual assault than did males (20.4% vs. 6.6%). Females who reported binge drinking (OR = 7.74) and other alcohol-related interpersonal violence (OR = 5.03) were more likely to report alcohol-related sexual assault whereas only other alcohol-related interpersonal violence was associated with alcohol-related sexual assault (OR = 43.75) among males. The findings suggest that alcohol-related sexual assault is associated with other risk factors that deserve further attention through longitudinal research and intervention efforts.

  18. Contingency Management Voucher Redemption as an Indicator of Delayed Gratification

    PubMed Central

    Fletcher, Jesse B.; Dierst-Davies, Rhodri; Reback, Cathy J.

    2014-01-01

    This prospective analysis tested whether frequency of voucher redemptions during a contingency management (CM) substance use intervention was significantly associated with participants’ ongoing substance use. Homeless, substance-dependent men who have sex with men (N=131) were randomized into either a “full” or “lite” voucher-based CM intervention. All participants earned vouchers for attendance and participation; participants in the CM-full condition also received vouchers for substance abstinence and enactment of prosocial and/or health-promoting behaviors. Multivariate longitudinal negative binomial regression analyses (n = 118) assessed the association between substance use during the intervention and frequency of voucher redemptions. Participants who used methamphetamine (IRR = 0.66; 95% CI=0.44–0.99) and/or opiates (IRR=0.60; 95% CI=0.40–0.99) during the intervention exhibited less time between voucher redemptions than individuals who achieved abstinence from these substances. Voucher redemption logs can be cost-effective and unobtrusive tools for measuring study participants’ tendency to delay gratification. PMID:24674235

  19. Kidney function changes with aging in adults: comparison between cross-sectional and longitudinal data analyses in renal function assessment.

    PubMed

    Chung, Sang M; Lee, David J; Hand, Austin; Young, Philip; Vaidyanathan, Jayabharathi; Sahajwalla, Chandrahas

    2015-12-01

    The study evaluated whether the renal function decline rate per year with age in adults varies based on two primary statistical analyses: cross-section (CS), using one observation per subject, and longitudinal (LT), using multiple observations per subject over time. A total of 16628 records (3946 subjects; age range 30-92 years) of creatinine clearance and relevant demographic data were used. On average, four samples per subject were collected for up to 2364 days (mean: 793 days). A simple linear regression and random coefficient models were selected for CS and LT analyses, respectively. The renal function decline rates per year were 1.33 and 0.95 ml/min/year for CS and LT analyses, respectively, and were slower when the repeated individual measurements were considered. The study confirms that rates are different based on statistical analyses, and that a statistically robust longitudinal model with a proper sampling design provides reliable individual as well as population estimates of the renal function decline rates per year with age in adults. In conclusion, our findings indicated that one should be cautious in interpreting the renal function decline rate with aging information because its estimation was highly dependent on the statistical analyses. From our analyses, a population longitudinal analysis (e.g. random coefficient model) is recommended if individualization is critical, such as a dose adjustment based on renal function during a chronic therapy. Copyright © 2015 John Wiley & Sons, Ltd.

  20. "Speaking Volumes": A Longitudinal Study of Lexical and Grammatical Growth between 17 and 42 Months

    ERIC Educational Resources Information Center

    Labrell, Florence; van Geert, Paul; Declercq, Christelle; Baltazart, Véronique; Caillies, Stéphanie; Olivier, Marie; Le Sourn-Bissaoui, Sandrine

    2014-01-01

    Dynamic analyses of language growth tell us how vocabulary and grammar develop and how the two might be intertwined. Analyses of growth curves between 17 and 42 months, based on longitudinal data for 34 children, revealed interesting patterns of vocabulary and grammatical developments. They showed that these patterns were nonlinear, but with…

  1. The intervals method: a new approach to analyse finite element outputs using multivariate statistics

    PubMed Central

    De Esteban-Trivigno, Soledad; Püschel, Thomas A.; Fortuny, Josep

    2017-01-01

    Background In this paper, we propose a new method, named the intervals’ method, to analyse data from finite element models in a comparative multivariate framework. As a case study, several armadillo mandibles are analysed, showing that the proposed method is useful to distinguish and characterise biomechanical differences related to diet/ecomorphology. Methods The intervals’ method consists of generating a set of variables, each one defined by an interval of stress values. Each variable is expressed as a percentage of the area of the mandible occupied by those stress values. Afterwards these newly generated variables can be analysed using multivariate methods. Results Applying this novel method to the biological case study of whether armadillo mandibles differ according to dietary groups, we show that the intervals’ method is a powerful tool to characterize biomechanical performance and how this relates to different diets. This allows us to positively discriminate between specialist and generalist species. Discussion We show that the proposed approach is a useful methodology not affected by the characteristics of the finite element mesh. Additionally, the positive discriminating results obtained when analysing a difficult case study suggest that the proposed method could be a very useful tool for comparative studies in finite element analysis using multivariate statistical approaches. PMID:29043107

  2. Computational neuroanatomy using brain deformations: From brain parcellation to multivariate pattern analysis and machine learning.

    PubMed

    Davatzikos, Christos

    2016-10-01

    The past 20 years have seen a mushrooming growth of the field of computational neuroanatomy. Much of this work has been enabled by the development and refinement of powerful, high-dimensional image warping methods, which have enabled detailed brain parcellation, voxel-based morphometric analyses, and multivariate pattern analyses using machine learning approaches. The evolution of these 3 types of analyses over the years has overcome many challenges. We present the evolution of our work in these 3 directions, which largely follows the evolution of this field. We discuss the progression from single-atlas, single-registration brain parcellation work to current ensemble-based parcellation; from relatively basic mass-univariate t-tests to optimized regional pattern analyses combining deformations and residuals; and from basic application of support vector machines to generative-discriminative formulations of multivariate pattern analyses, and to methods dealing with heterogeneity of neuroanatomical patterns. We conclude with discussion of some of the future directions and challenges. Copyright © 2016. Published by Elsevier B.V.

  3. Computational neuroanatomy using brain deformations: From brain parcellation to multivariate pattern analysis and machine learning

    PubMed Central

    Davatzikos, Christos

    2017-01-01

    The past 20 years have seen a mushrooming growth of the field of computational neuroanatomy. Much of this work has been enabled by the development and refinement of powerful, high-dimensional image warping methods, which have enabled detailed brain parcellation, voxel-based morphometric analyses, and multivariate pattern analyses using machine learning approaches. The evolution of these 3 types of analyses over the years has overcome many challenges. We present the evolution of our work in these 3 directions, which largely follows the evolution of this field. We discuss the progression from single-atlas, single-registration brain parcellation work to current ensemble-based parcellation; from relatively basic mass-univariate t-tests to optimized regional pattern analyses combining deformations and residuals; and from basic application of support vector machines to generative-discriminative formulations of multivariate pattern analyses, and to methods dealing with heterogeneity of neuroanatomical patterns. We conclude with discussion of some of the future directions and challenges. PMID:27514582

  4. Multivariate meta-analysis using individual participant data

    PubMed Central

    Riley, R. D.; Price, M. J.; Jackson, D.; Wardle, M.; Gueyffier, F.; Wang, J.; Staessen, J. A.; White, I. R.

    2016-01-01

    When combining results across related studies, a multivariate meta-analysis allows the joint synthesis of correlated effect estimates from multiple outcomes. Joint synthesis can improve efficiency over separate univariate syntheses, may reduce selective outcome reporting biases, and enables joint inferences across the outcomes. A common issue is that within-study correlations needed to fit the multivariate model are unknown from published reports. However, provision of individual participant data (IPD) allows them to be calculated directly. Here, we illustrate how to use IPD to estimate within-study correlations, using a joint linear regression for multiple continuous outcomes and bootstrapping methods for binary, survival and mixed outcomes. In a meta-analysis of 10 hypertension trials, we then show how these methods enable multivariate meta-analysis to address novel clinical questions about continuous, survival and binary outcomes; treatment–covariate interactions; adjusted risk/prognostic factor effects; longitudinal data; prognostic and multiparameter models; and multiple treatment comparisons. Both frequentist and Bayesian approaches are applied, with example software code provided to derive within-study correlations and to fit the models. PMID:26099484

  5. On the Power of Multivariate Latent Growth Curve Models to Detect Correlated Change

    ERIC Educational Resources Information Center

    Hertzog, Christopher; Lindenberger, Ulman; Ghisletta, Paolo; Oertzen, Timo von

    2006-01-01

    We evaluated the statistical power of single-indicator latent growth curve models (LGCMs) to detect correlated change between two variables (covariance of slopes) as a function of sample size, number of longitudinal measurement occasions, and reliability (measurement error variance). Power approximations following the method of Satorra and Saris…

  6. Social-Psychological and Educational Outcomes Associated with Peer Victimization among Korean Adolescents

    ERIC Educational Resources Information Center

    Cho, Rosa Minhyo; Choi, Jaesung

    2017-01-01

    This study examines the effects of peer victimization by verbal, physical, and relational bullying on Korean adolescents' self-worth, disconnect to peers, school engagement, and academic achievement. A two-year longitudinal survey on 3,266 sixth-graders attending school in Seoul, Korea was used. Multivariate regression results controlling for…

  7. Factors Associated with Participation in Employment for High School Leavers with Autism

    ERIC Educational Resources Information Center

    Chiang, Hsu-Min; Cheung, Ying Kuen; Li, Huacheng; Tsai, Luke Y.

    2013-01-01

    This study aimed to identify the factors associated with participation in employment for high school leavers with autism. A secondary data analysis of the National Longitudinal Transition Study 2 (NLTS2) data was performed. Potential factors were assessed using a weighted multivariate logistic regression. This study found that annual household…

  8. Developmental Patterns in Marital Satisfaction: Another Look at Covenant Marriage

    ERIC Educational Resources Information Center

    DeMaris, Alfred; Sanchez, Laura A.; Krivickas, Kristi

    2012-01-01

    This study investigated differences in the trajectory of marital satisfaction in the first 7 years between couples in covenant versus standard marriages. The authors analyzed data on 707 Louisiana marriages from the Marriage Matters Panel Survey of Newlywed Couples, 1998-2004, using multivariate longitudinal growth modeling. When the sample was…

  9. Longitudinal associations of lifestyle factors and weight status with insulin resistance (HOMA-IR) in preadolescent children: the large prospective cohort study IDEFICS.

    PubMed

    Peplies, Jenny; Börnhorst, Claudia; Günther, Kathrin; Fraterman, Arno; Russo, Paola; Veidebaum, Toomas; Tornaritis, Michael; De Henauw, Stefaan; Marild, Staffan; Molnar, Dénes; Moreno, Luis A; Ahrens, Wolfgang

    2016-09-02

    This study investigates prospective associations of anthropometrical and lifestyle indices with insulin resistance (IR) in European children from the IDEFICS cohort. Insulin resistance (IR) is a growing concern in childhood obesity and a central aspect of the metabolic syndrome (MS). It most likely represents the link between obesity and type 2 diabetes. This longitudinal study included 3348 preadolescent children aged 3 to 10.9 years from 8 European countries who were observed from 2007/2008 to 2009/2010. The main outcome measure in the present analysis is HOMA-IR (homeostasis model assessment as a common proxy indicator to quantify IR) at follow-up and in its longitudinal development. Anthropometrical measures and lifestyle indices, including objectively determined physical activity, were considered, among others factors, as determinants of IR. Prospective associations between IR at follow-up and anthropometrical and lifestyle indices were estimated by logistic regression models. Country-specific prevalence rates of IR in the IDEFICS cohort of European children showed a positive trend with weight category. Prospective multivariate analyses showed the strongest positive associations of IR with BMI z-score (OR = 2.6 for unit change from the mean, 95 % CI 2.1-3.1) and z-score of waist circumference (OR = 2.2 for unit change from the mean, 95 % CI 1.9-2.6), which were analysed in separate models, but also for sex (OR = 2.2 for girls vs. boys, 95 % CI 1.5-3.1 up to OR 2.5, 95 % CI 1.8-3.6 depending on the model), audio-visual media time (OR = 1.2 for an additional hour per day, 95 % CI 1.0-1.4 in both models) and an inverse association of objectively determined physical activity (OR = 0.5 for 3(rd) compared to 1(st) quartile, 95 % CI 0.3-0.9 in both models). A longitudinal reduction of HOMA-IR was accompanied with a parallel decline in BMI. This study is, to our knowledge, the first prospective study on IR in a preadolescent children's population. It supports the common hypothesis that overweight and obesity are the main determinants of IR. Our data also indicate that physical inactivity and a sedentary lifestyle are likewise associated with the development of IR, independent of weight status. The promotion of physical activity should thus be considered as an equal option to dietary intervention for the treatment of IR in the paediatric practice.

  10. Multi-country health surveys: are the analyses misleading?

    PubMed

    Masood, Mohd; Reidpath, Daniel D

    2014-05-01

    The aim of this paper was to review the types of approaches currently utilized in the analysis of multi-country survey data, specifically focusing on design and modeling issues with a focus on analyses of significant multi-country surveys published in 2010. A systematic search strategy was used to identify the 10 multi-country surveys and the articles published from them in 2010. The surveys were selected to reflect diverse topics and foci; and provide an insight into analytic approaches across research themes. The search identified 159 articles appropriate for full text review and data extraction. The analyses adopted in the multi-country surveys can be broadly classified as: univariate/bivariate analyses, and multivariate/multivariable analyses. Multivariate/multivariable analyses may be further divided into design- and model-based analyses. Of the 159 articles reviewed, 129 articles used model-based analysis, 30 articles used design-based analyses. Similar patterns could be seen in all the individual surveys. While there is general agreement among survey statisticians that complex surveys are most appropriately analyzed using design-based analyses, most researchers continued to use the more common model-based approaches. Recent developments in design-based multi-level analysis may be one approach to include all the survey design characteristics. This is a relatively new area, however, and there remains statistical, as well as applied analytic research required. An important limitation of this study relates to the selection of the surveys used and the choice of year for the analysis, i.e., year 2010 only. There is, however, no strong reason to believe that analytic strategies have changed radically in the past few years, and 2010 provides a credible snapshot of current practice.

  11. Borrowing of strength and study weights in multivariate and network meta-analysis.

    PubMed

    Jackson, Dan; White, Ian R; Price, Malcolm; Copas, John; Riley, Richard D

    2017-12-01

    Multivariate and network meta-analysis have the potential for the estimated mean of one effect to borrow strength from the data on other effects of interest. The extent of this borrowing of strength is usually assessed informally. We present new mathematical definitions of 'borrowing of strength'. Our main proposal is based on a decomposition of the score statistic, which we show can be interpreted as comparing the precision of estimates from the multivariate and univariate models. Our definition of borrowing of strength therefore emulates the usual informal assessment. We also derive a method for calculating study weights, which we embed into the same framework as our borrowing of strength statistics, so that percentage study weights can accompany the results from multivariate and network meta-analyses as they do in conventional univariate meta-analyses. Our proposals are illustrated using three meta-analyses involving correlated effects for multiple outcomes, multiple risk factor associations and multiple treatments (network meta-analysis).

  12. Borrowing of strength and study weights in multivariate and network meta-analysis

    PubMed Central

    Jackson, Dan; White, Ian R; Price, Malcolm; Copas, John; Riley, Richard D

    2016-01-01

    Multivariate and network meta-analysis have the potential for the estimated mean of one effect to borrow strength from the data on other effects of interest. The extent of this borrowing of strength is usually assessed informally. We present new mathematical definitions of ‘borrowing of strength’. Our main proposal is based on a decomposition of the score statistic, which we show can be interpreted as comparing the precision of estimates from the multivariate and univariate models. Our definition of borrowing of strength therefore emulates the usual informal assessment. We also derive a method for calculating study weights, which we embed into the same framework as our borrowing of strength statistics, so that percentage study weights can accompany the results from multivariate and network meta-analyses as they do in conventional univariate meta-analyses. Our proposals are illustrated using three meta-analyses involving correlated effects for multiple outcomes, multiple risk factor associations and multiple treatments (network meta-analysis). PMID:26546254

  13. Joint Models of Longitudinal and Time-to-Event Data with More Than One Event Time Outcome: A Review.

    PubMed

    Hickey, Graeme L; Philipson, Pete; Jorgensen, Andrea; Kolamunnage-Dona, Ruwanthi

    2018-01-31

    Methodological development and clinical application of joint models of longitudinal and time-to-event outcomes have grown substantially over the past two decades. However, much of this research has concentrated on a single longitudinal outcome and a single event time outcome. In clinical and public health research, patients who are followed up over time may often experience multiple, recurrent, or a succession of clinical events. Models that utilise such multivariate event time outcomes are quite valuable in clinical decision-making. We comprehensively review the literature for implementation of joint models involving more than a single event time per subject. We consider the distributional and modelling assumptions, including the association structure, estimation approaches, software implementations, and clinical applications. Research into this area is proving highly promising, but to-date remains in its infancy.

  14. Frequency Doubling Technology Perimetry and Changes in Quality of Life of Glaucoma Patients: A Longitudinal Study.

    PubMed

    Abe, Ricardo Y; Gracitelli, Carolina P B; Diniz-Filho, Alberto; Zangwill, Linda M; Weinreb, Robert N; Medeiros, Felipe A

    2015-07-01

    To evaluate the relationship between rates of change on frequency doubling technology (FDT) perimetry and longitudinal changes in quality of life (QoL) of glaucoma patients. Prospective observational cohort study. One hundred fifty-two subjects (127 glaucoma and 25 healthy) were followed for an average of 3.2 ± 1.1 years. All subjects were evaluated with National Eye Institute Visual Function Questionnaire (NEI VFQ-25), FDT, and standard automated perimetry (SAP). Glaucoma patients had a median of 3 NEI VFQ-25, 8 FDT, and 8 SAP tests during follow-up. Mean sensitivities of the integrated binocular visual fields were estimated for FDT and SAP and used to calculate rates of change. A joint longitudinal multivariable mixed model was used to investigate the association between change in binocular mean sensitivities and change in NEI VFQ-25 Rasch-calibrated scores. There was a statistically significant correlation between change in binocular mean sensitivity for FDT and change in NEI VFQ-25 scores during follow-up in the glaucoma group. In multivariable analysis with the confounding factors, each 1 dB/year change in binocular FDT mean sensitivity corresponded to a change of 0.8 units per year in the NEI VFQ-25 scores (P = .001). For binocular SAP mean sensitivity, each 1 dB/year change was associated with 2.4 units per year change in NEI VFQ-25 scores (P < .001). The multivariable model containing baseline and rate of change information from SAP had stronger ability to predict change in NEI VFQ-25 scores compared to the equivalent model for FDT (R(2) of 50% and 30%, respectively; P = .001). SAP performed significantly better than FDT in predicting change in NEI VFQ-25 scores in our population, suggesting that it may still be the preferable perimetric technique for predicting risk of disability from the disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Self-Concept Clarity in Adolescents and Parents: A Six-Wave Longitudinal and Multi-Informant Study on Development and Intergenerational Transmission.

    PubMed

    Crocetti, Elisabetta; Rubini, Monica; Branje, Susan; Koot, Hans M; Meeus, Wim

    2016-10-01

    The purpose of this study was twofold: (a) to disentangle patterns of change and stability in self-concept clarity (SCC) in adolescents and in their parents and (b) to examine processes of intergenerational transmission of SCC in families with adolescents. Participants were 497 Dutch families including the father (baseline Mage  = 46.74), the mother (baseline Mage  = 44.41), and their adolescent child (56.9% males; baseline Mage  = 13.03). Each family member completed the SCC scale for six waves, with a one-year interval between each wave. Latent growth curve analyses indicated that adolescent boys reported higher SCC than girls. Furthermore, fathers and mothers reported higher SCC than their children, and it increased over time. Indices of SCC rank-order stability were high and increased from T1 to T2, T2 to T3, etc., for each family member, especially for adolescents. Multivariate latent growth curve analyses and cross-lagged models highlighted a unidirectional transmission process, with fathers' and mothers' SCC influencing adolescents' SCC. This result was not moderated by adolescent gender. These findings indicate that self-concept clarity is transmitted from parents to children. © 2015 Wiley Periodicals, Inc.

  16. Dog Ownership, Physical Activity, and Health-Related Quality of Life in Veterinary Students: A Cross-Sectional Study.

    PubMed

    Corrigan, Virginia K; Pierce, Bess J; Hosig, Kathy

    The primary objective of this cross-sectional study was to examine the relationship between dog ownership and physical activity in veterinary students. The secondary objective was to gain an understanding of veterinary students' health-related quality of life (HRQOL), and whether dog ownership and/or physical activity were associated with HRQOL measures. Veterinary students were invited to complete surveys between September and November 2015. The primary outcome for multivariate analyses was self-reported physical activity. Bivariate analyses and descriptive statistics were performed to assess student HRQOL. The survey response rate was 33% (152/460). Self-efficacy to exercise (p<.001, OR 2.24, 95% CI 1.46-3.44) and dog ownership (p=.01, OR 3.38, 95% CI 1.31-8.71) independently predicted meeting physical activity guidelines when controlling for other variables. About two thirds of respondents met physical activity guidelines. Veterinary students had significantly worse self-reported mental health scores when compared to both national and state averages. Neither dog ownership nor meeting physical activity guidelines were significantly associated with measures of HRQOL. The poor mental health status of veterinary students remains a significant issue for the profession to address. Longitudinal studies are needed that examine the relationship between physical activity and mental health outcomes in this population.

  17. Risk and protective factors associated with speech and language impairment in a nationally representative sample of 4- to 5-year-old children.

    PubMed

    Harrison, Linda J; McLeod, Sharynne

    2010-04-01

    To determine risk and protective factors for speech and language impairment in early childhood. Data are presented for a nationally representative sample of 4,983 children participating in the Longitudinal Study of Australian Children (described in McLeod & Harrison, 2009). Thirty-one child, parent, family, and community factors previously reported as being predictors of speech and language impairment were tested as predictors of (a) parent-rated expressive speech/language concern and (b) receptive language concern, (c) use of speech-language pathology services, and (d) low receptive vocabulary. Bivariate logistic regression analyses confirmed 29 of the identified factors. However, when tested concurrently with other predictors in multivariate analyses, only 19 remained significant: 9 for 2-4 outcomes and 10 for 1 outcome. Consistent risk factors were being male, having ongoing hearing problems, and having a more reactive temperament. Protective factors were having a more persistent and sociable temperament and higher levels of maternal well-being. Results differed by outcome for having an older sibling, parents speaking a language other than English, and parental support for children's learning at home. Identification of children requiring speech and language assessment requires consideration of the context of family life as well as biological and psychosocial factors intrinsic to the child.

  18. Pretest-Posttest-Posttest Multilevel IRT Modeling of Competence Growth of Students in Higher Education in Germany

    ERIC Educational Resources Information Center

    Schmidt, Susanne; Zlatkin-Troitschanskaia, Olga; Fox, Jean-Paul

    2016-01-01

    Longitudinal research in higher education faces several challenges. Appropriate methods of analyzing competence growth of students are needed to deal with those challenges and thereby obtain valid results. In this article, a pretest-posttest-posttest multivariate multilevel IRT model for repeated measures is introduced which is designed to address…

  19. Long-Term Stability of Core Language Skill in Children with Contrasting Language Skills

    ERIC Educational Resources Information Center

    Bornstein, Marc H.; Hahn, Chun-Shin; Putnick, Diane L.

    2016-01-01

    This 4-wave longitudinal study evaluated stability of core language skill in 421 European American and African American children, half of whom were identified as low (n = 201) and half of whom were average-to-high (n = 220) in later language skill. Structural equation modeling supported loadings of multivariate age-appropriate multisource measures…

  20. Are Adolescent Substance Users Less Satisfied with Life as Young Adults and if so, Why?

    ERIC Educational Resources Information Center

    Bogart, Laura M.; Collins, Rebecca L.; Ellickson, Phyllis L.; Klein, David J.

    2007-01-01

    The present study investigated whether adolescent cigarette, alcohol, marijuana, and hard drug use predicts life satisfaction in young adulthood. Survey data were used from a longitudinal cohort of 2376 adolescents at ages 18 and 29, originally recruited from California and Oregon middle schools at age 13. Results of multivariate models indicated…

  1. Embodiment Feels Better: Girls' Body Objectification and Well-Being across Adolescence

    ERIC Educational Resources Information Center

    Impett, Emily A.; Henson, James M.; Breines, Juliana G.; Schooler, Deborah; Tolman, Deborah L.

    2011-01-01

    In a five-year longitudinal study, we investigated the role of body objectification in shaping girls' self-esteem and depressive symptoms over the course of adolescence. Multivariate Latent Growth Curve Modeling (MLGM) was used to test the association between body objectification and both self-esteem and depressive symptoms with data from 587…

  2. Studying the Relationship between Children's Self-Control and Academic Achievement: An Application of Second-Order Growth Curve Model Analysis.

    ERIC Educational Resources Information Center

    Kim, Sooyeon; Murry, Velma McBride; Brody, Gene H.

    The functional relationships between developmental change in children's self-control and academic achievement were examined using longitudinal family data. Multivariate latent growth models (LGM) were specified to determine whether the rate of growth in academic achievement changes as a function of developmental change in self-control. Data came…

  3. The College Application Gauntlet: A Systematic Analysis of the Steps to Four-Year College Enrollment

    ERIC Educational Resources Information Center

    Klasik, Daniel

    2012-01-01

    Few studies have examined the steps to college enrollment between college aspiration and college enrollment and how these steps might present a barrier to four-year college enrollment. This study used data from the Education Longitudinal Study: 2002 and employed a multivariate random effects logistic framework to examine the completion of nine…

  4. The Roles of Victim and Offender Substance Use in Sexual Assault Outcomes

    ERIC Educational Resources Information Center

    Brecklin, Leanne R.; Ullman, Sarah E.

    2010-01-01

    The impact of victim and offender preassault substance use on the outcomes of sexual assault incidents was analyzed. Nine hundred and seventy female sexual assault victims were identified from the first wave of a longitudinal study based on a convenience sampling strategy. Multivariate models showed that victim injury was more likely in assaults…

  5. Career Adaptability Development in Adolescence: Multiple Predictors and Effect on Sense of Power and Life Satisfaction

    ERIC Educational Resources Information Center

    Hirschi, Andreas

    2009-01-01

    This longitudinal panel study investigated predictors of career adaptability development and its effect on development of sense of power and experience of life satisfaction among 330 Swiss eighth graders. A multivariate measure of career adaptability consisting of career choice readiness, planning, exploration, and confidence was applied. Based on…

  6. Mental and Motor Growth Patterns and Growth Velocity of Indian Babies. (Longitudinal Growth of Indian Children). Research Report No. 4.

    ERIC Educational Resources Information Center

    Phatak, Pramila; And Others

    This study reports various aspects of the analyses carried out on the longitudinal data reported in a previous study (PS 007 345) for determining the general growth patterns and growth velocity of mental and motor development. Preliminary analyses focused on the selection of the growth curve, its evaluation in the 208 individual cases, and the…

  7. Attention deficit hyperactivity disorder and personality characteristics in older adults in the general Dutch population.

    PubMed

    Michielsen, Marieke; Comijs, Hannie C; Semeijn, Evert J; Beekman, Aartjan T F; Deeg, Dorly J H; Kooij, J J Sandra

    2014-12-01

    The authors wanted to examine the association between attention deficit hyperactivity disorder (ADHD) and personality characteristics and the potential mediating role of these characteristics in the relationship between ADHD and depression in older adults in the general Dutch population. Data from the Longitudinal Aging Study Amsterdam in 2008/2009 were used in a cross-sectional design on 231 participants with and without ADHD aged 60-94 years. Questionnaires assessing self-esteem, self-efficacy, mastery, neuroticism, and social inadequacy were administered. ADHD was measured by means of ADHD diagnosis and level of ADHD symptoms. Linear regression analyses were performed to assess the association between ADHD (symptoms) and personality characteristics. Single and multivariate mediation analyses were performed to examine the mediating role of personality characteristics in the relationship between ADHD (symptoms) and depressive symptoms. ADHD was significantly negatively associated with sense of mastery (B = -2.44, t = -3.14, df = 228, p = 0.002), self-esteem (B = -1.16, t = -2.27, df = 228, p = 0.02), and self-efficacy (B = -2.33, t = -2.02, df = 228, p = 0.045) and positively associated with neuroticism (B = 0.99, t = 4.90, df = 228, p <0.001) and social inadequacy (B = 0.65, t = 3.32, df = 229, p = 0.001). In the single mediation analyses, all personality characteristics were mediators in the relationship between ADHD symptoms and depressive symptoms. In the multivariate analysis only mastery and self-esteem were mediators. Older adults with ADHD reported lower self-esteem and sense of mastery and higher levels of neuroticism and social inadequacy than older adults without ADHD. Mastery and self-esteem partly explained the association between ADHD and depressive symptoms in old age. The results implicate that in treatment clinicians should pay attention to the personality characteristics of older adults with ADHD. Copyright © 2014 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

  8. Motivations to eat healthily in older Dutch adults--a cross sectional study.

    PubMed

    Dijkstra, S Coosje; Neter, Judith E; Brouwer, Ingeborg A; Huisman, Martijn; Visser, Marjolein

    2014-11-18

    To influence dietary behaviors, more insight in food choice motivations is necessary. This study identified what motivations older adults have to eat healthily and investigated to what extent these motivations are particular to specific subgroups according to socio-economic position and other demographic, lifestyle and health characteristics. We used data from 1,050 older Dutch adults who participated in the Longitudinal Aging Study Amsterdam (65-80 years, independently living, normal cognitive status). Motivations to eat healthily and characteristics were measured with a self-reported questionnaire. We used logistic regression analyses to estimate odds ratios (OR) and 95% CI for the association between subgroups and motivations to eat healthily. The most reported motivations to eat healthily were: "feeling fit" (51.7%), "current health" (49.7%) and "body weight" (39.2%). Multivariate analyses showed that older adults with chronic diseases (≥2 vs. no chronic disease OR: 4.41, 95% CI: 2.31-8.44) and a poor self-rated health (poor vs. good OR: 2.31, 95% CI: 1.22-3.73) were more likely to report "current disease" as a motivation to eat healthily. Groups from lower socio-economic positions were less likely to report "to prevent diseases" (low income vs. high OR: 0.52, 95% CI: 0.32-0.86, low education vs. high OR: 0.43, 95% CI: 0.27-0.70) and older adults with obesity were less likely to report "current health" (obese vs. normal weight OR: 0.47, 95% CI: 0.32-0.69) as motivations to eat healthily. Multivariate analyses showed that the presence of a disease in older adults is an important motivation for them to eat healthily, which might indicate that older adults with health problems are aware of the link between their disease and nutrition. Older adults from lower socio-economic positions or those with obesity require a specific approach because disease prevention seems to be of lesser importance for these groups, even though a healthy diet could improve their health. Future research should investigate the reasons behind the motives of low socio-economic position and obese older adults.

  9. Sample size calculations for case-control studies

    Cancer.gov

    This R package can be used to calculate the required samples size for unconditional multivariate analyses of unmatched case-control studies. The sample sizes are for a scalar exposure effect, such as binary, ordinal or continuous exposures. The sample sizes can also be computed for scalar interaction effects. The analyses account for the effects of potential confounder variables that are also included in the multivariate logistic model.

  10. A Semiparametric Approach to Simultaneous Covariance Estimation for Bivariate Sparse Longitudinal Data

    PubMed Central

    Das, Kiranmoy; Daniels, Michael J.

    2014-01-01

    Summary Estimation of the covariance structure for irregular sparse longitudinal data has been studied by many authors in recent years but typically using fully parametric specifications. In addition, when data are collected from several groups over time, it is known that assuming the same or completely different covariance matrices over groups can lead to loss of efficiency and/or bias. Nonparametric approaches have been proposed for estimating the covariance matrix for regular univariate longitudinal data by sharing information across the groups under study. For the irregular case, with longitudinal measurements that are bivariate or multivariate, modeling becomes more difficult. In this article, to model bivariate sparse longitudinal data from several groups, we propose a flexible covariance structure via a novel matrix stick-breaking process for the residual covariance structure and a Dirichlet process mixture of normals for the random effects. Simulation studies are performed to investigate the effectiveness of the proposed approach over more traditional approaches. We also analyze a subset of Framingham Heart Study data to examine how the blood pressure trajectories and covariance structures differ for the patients from different BMI groups (high, medium and low) at baseline. PMID:24400941

  11. Impact of videogame play on the brain's microstructural properties: cross-sectional and longitudinal analyses.

    PubMed

    Takeuchi, H; Taki, Y; Hashizume, H; Asano, K; Asano, M; Sassa, Y; Yokota, S; Kotozaki, Y; Nouchi, R; Kawashima, R

    2016-12-01

    Videogame play (VGP) has been associated with numerous preferred and non-preferred effects. However, the effects of VGP on the development of microstructural properties in children, particularly those associated with negative psychological consequences of VGP, have not been identified to date. The purpose of this study was to investigate this issue through cross-sectional and longitudinal prospective analyses. In the present study of humans, we used the diffusion tensor imaging mean diffusivity (MD) measurement to measure microstructural properties and examined cross-sectional correlations with the amount of VGP in 114 boys and 126 girls. We also assessed correlations between the amount of VGP and longitudinal changes in MD that developed after 3.0±0.3 (s.d.) years in 95 boys and 94 girls. After correcting for confounding factors, we found that the amount of VGP was associated with increased MD in the left middle, inferior and orbital frontal cortex; left pallidum; left putamen; left hippocampus; left caudate; right putamen; right insula; and thalamus in both cross-sectional and longitudinal analyses. Regardless of intelligence quotient type, higher MD in the areas of the left thalamus, left hippocampus, left putamen, left insula and left Heschl gyrus was associated with lower intelligence. We also confirmed an association between the amount of VGP and decreased verbal intelligence in both cross-sectional and longitudinal analyses. In conclusion, increased VGP is directly or indirectly associated with delayed development of the microstructure in extensive brain regions and verbal intelligence.

  12. Impact of videogame play on the brain's microstructural properties: cross-sectional and longitudinal analyses

    PubMed Central

    Takeuchi, H; Taki, Y; Hashizume, H; Asano, K; Asano, M; Sassa, Y; Yokota, S; Kotozaki, Y; Nouchi, R; Kawashima, R

    2016-01-01

    Videogame play (VGP) has been associated with numerous preferred and non-preferred effects. However, the effects of VGP on the development of microstructural properties in children, particularly those associated with negative psychological consequences of VGP, have not been identified to date. The purpose of this study was to investigate this issue through cross-sectional and longitudinal prospective analyses. In the present study of humans, we used the diffusion tensor imaging mean diffusivity (MD) measurement to measure microstructural properties and examined cross-sectional correlations with the amount of VGP in 114 boys and 126 girls. We also assessed correlations between the amount of VGP and longitudinal changes in MD that developed after 3.0±0.3 (s.d.) years in 95 boys and 94 girls. After correcting for confounding factors, we found that the amount of VGP was associated with increased MD in the left middle, inferior and orbital frontal cortex; left pallidum; left putamen; left hippocampus; left caudate; right putamen; right insula; and thalamus in both cross-sectional and longitudinal analyses. Regardless of intelligence quotient type, higher MD in the areas of the left thalamus, left hippocampus, left putamen, left insula and left Heschl gyrus was associated with lower intelligence. We also confirmed an association between the amount of VGP and decreased verbal intelligence in both cross-sectional and longitudinal analyses. In conclusion, increased VGP is directly or indirectly associated with delayed development of the microstructure in extensive brain regions and verbal intelligence. PMID:26728566

  13. Seismic Design of a Single Bored Tunnel: Longitudinal Deformations and Seismic Joints

    NASA Astrophysics Data System (ADS)

    Oh, J.; Moon, T.

    2018-03-01

    The large diameter bored tunnel passing through rock and alluvial deposits subjected to seismic loading is analyzed for estimating longitudinal deformations and member forces on the segmental tunnel liners. The project site has challenges including high hydrostatic pressure, variable ground profile and high seismic loading. To ensure the safety of segmental tunnel liner from the seismic demands, the performance-based two-level design earthquake approach, Functional Evaluation Earthquake and Safety Evaluation Earthquake, has been adopted. The longitudinal tunnel and ground response seismic analyses are performed using a three-dimensional quasi-static linear elastic and nonlinear elastic discrete beam-spring elements to represent segmental liner and ground spring, respectively. Three components (longitudinal, transverse and vertical) of free-field ground displacement-time histories evaluated from site response analyses considering wave passage effects have been applied at the end support of the strain-compatible ground springs. The result of the longitudinal seismic analyses suggests that seismic joint for the mitigation measure requiring the design deflection capacity of 5-7.5 cm is to be furnished at the transition zone between hard and soft ground condition where the maximum member forces on the segmental liner (i.e., axial, shear forces and bending moments) are induced. The paper illustrates how detailed numerical analyses can be practically applied to evaluate the axial and curvature deformations along the tunnel alignment under difficult ground conditions and to provide the seismic joints at proper locations to effectively reduce the seismic demands below the allowable levels.

  14. Early Childhood Memory and Attention as Predictors of Academic Growth Trajectories

    ERIC Educational Resources Information Center

    Stipek, Deborah; Valentino, Rachel A.

    2015-01-01

    Longitudinal data from the children of the National Longitudinal Survey of Youth (NLSY) were used to assess how well measures of short-term and working memory and attention in early childhood predicted longitudinal growth trajectories in mathematics and reading comprehension. Analyses also examined whether changes in memory and attention were more…

  15. Reducing Bias Due to Systematic Attrition in Longitudinal Studies: The Benefits of Multiple Imputation

    ERIC Educational Resources Information Center

    Asendorpf, Jens B.; van de Schoot, Rens; Denissen, Jaap J. A.; Hutteman, Roos

    2014-01-01

    Most longitudinal studies are plagued by drop-out related to variables at earlier assessments (systematic attrition). Although systematic attrition is often analysed in longitudinal studies, surprisingly few researchers attempt to reduce biases due to systematic attrition, even though this is possible and nowadays technically easy. This is…

  16. Mental health selection and income support dynamics: multiple spell discrete-time survival analyses of welfare receipt.

    PubMed

    Kiely, Kim M; Butterworth, Peter

    2014-04-01

    The higher occurrence of common psychiatric disorders among welfare recipients has been attributed to health selection, social causation and underlying vulnerability. The aims of this study were to test for the selection effects of mental health problems on entry and re-entry to working-age welfare payments in respect to single parenthood, unemployment and disability. Nationally representative longitudinal data were drawn from the Household Income and Labour Dynamics in Australia survey. Multiple spell discrete-time survival analyses were conducted using multinomial logistic regression models to test if pre-existing mental health problems predicted transitions to welfare. Analyses were stratified by sex and multivariate adjusted for mental health problems, father's occupation, socioeconomic position, marital status, employment history, smoking status and alcohol consumption, physical function and financial hardship. All covariates were modelled as either lagged effects or when a respondent was first observed to be at risk of income support. Mental health problems were associated with increased risk of entry and re-entry to disability, unemployment and single parenting payments for women, and disability and unemployment payments for men. These associations were attenuated but remained significant after adjusting for contemporaneous risk factors. Although we do not control for reciprocal causation, our findings are consistent with a health selection hypothesis and indicate that mental illness may be a contributing factor to later receipt of different types of welfare payments. We argue that mental health warrants consideration in the design and targeting of social and economic policies.

  17. Understanding the role of conscientiousness in healthy aging: where does the brain come in?

    PubMed

    Patrick, Christopher J

    2014-05-01

    In reviewing this impressive series of articles, I was struck by 2 points in particular: (a) the fact that the empirically oriented articles focused on analyses of data from very large samples, with the articles by Friedman, Kern, Hampson, and Duckworth (2014) and Kern, Hampson, Goldbert, and Friedman (2014) highlighting an approach to merging existing data sets through use of "metric bridges" to address key questions not addressable through 1 data set alone, and (b) the fact that the articles as a whole included limited mention of neuroscientific (i.e., brain research) concepts, methods, and findings. One likely reason for the lack of reference to brain-oriented work is the persisting gap between smaller sample size lab-experimental and larger sample size multivariate-correlational approaches to psychological research. As a strategy for addressing this gap and bringing a distinct neuroscientific component to the National Institute on Aging's conscientiousness and health initiative, I suggest that the metric bridging approach highlighted by Friedman and colleagues could be used to connect existing large-scale data sets containing both neurophysiological variables and measures of individual difference constructs to other data sets containing richer arrays of nonphysiological variables-including data from longitudinal or twin studies focusing on personality and health-related outcomes (e.g., Terman Life Cycle study and Hawaii longitudinal studies, as described in the article by Kern et al., 2014). (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  18. Quality of life of nursing-home residents with dementia subject to surveillance technology versus physical restraints: an explorative study.

    PubMed

    Te Boekhorst, S; Depla, M F I A; Francke, A L; Twisk, J W R; Zwijsen, S A; Hertogh, C M P M

    2013-04-01

    As physical restraints should only be used in exceptional cases, there is an urgent need for alternatives to restraint use. Surveillance technology could be such an alternative. This study explored whether nursing-home residents with dementia subjected to surveillance technology had better quality of life scores for mood, behavioral and societal dimensions than residents with physical restraints. Quality of life was assessed longitudinally, with three measurements in six psychogeriatric nursing homes of residents with surveillance technology (n = 170) and residents with physical restraints (n = 22). QUALIDEM subscales were used to measure five dimensions of quality of life. Multilevel longitudinal univariate and multivariate regression techniques were used to analyze the data. Because physical restraints were almost exclusively used in residents with low activities of daily living (ADL) independency (18 of the 22), we restricted the regression analyses to residents with a Barthel Index score ≤ 5 (overall n = 53). Univariate results showed that highly ADL-dependent residents with surveillance technology had significantly more positive affect than highly ADL-dependent residents with physical restraints. However, this difference proved to be no longer significant after adjustment for the confounders: age, sex and stage of dementia. Quality of life of highly ADL-dependent nursing-home residents with dementia seems to be unrelated to the use of surveillance technology as opposed to physical restraints. Copyright © 2012 John Wiley & Sons, Ltd.

  19. Science-related Aspirations Across the Primary-Secondary Divide: Evidence from two surveys in England

    NASA Astrophysics Data System (ADS)

    DeWitt, Jennifer; Archer, Louise; Osborne, Jonathan

    2014-07-01

    Students' engagement with science and the numbers pursuing further study of science continue to be a concern among policy-makers, particularly in Western countries. Previous research reflects that most children have positive attitudes to science at age 10 but that, by age 14, attitudes towards and interest in further pursuit of science have declined. The Science Aspirations and Career Choice (ASPIRES) project, a 5-year longitudinal study, seeks to trace and track changes in students' interest in science and in scientific careers over the key period of ages 10-14. Building on an initial survey (consisting primarily of Likert-type items) of over 9,000 children in their last year of primary school, we explore shifts in attitudes and aspirations in science as reflected in a second survey of students from this cohort (over 5,600 students), completed when children were in their second year of secondary school (ages 12-13). Survey findings are supplemented by longitudinal interview data from 85 children. Contrary to previous research, descriptive, multivariate and multi-level modelling (MLM) analyses of the data indicate that the majority of our sample enjoy school science in secondary school and hold positive views of scientists. However, as with the primary school data, these positive attitudes also continue not to translate into an interest in 'being' a scientist. Attention is drawn to the importance of families and student experiences of school science in helping to explain this gap.

  20. Adolescent Executive Dysfunction in Daily Life: Relationships to Risks, Brain Structure and Substance Use

    PubMed Central

    Clark, Duncan B.; Chung, Tammy; Martin, Christopher S.; Hasler, Brant P.; Fitzgerald, Douglas H.; Luna, Beatriz; Brown, Sandra A.; Tapert, Susan F.; Brumback, Ty; Cummins, Kevin; Pfefferbaum, Adolf; Sullivan, Edith V.; Pohl, Kilian M.; Colrain, Ian M.; Baker, Fiona C.; De Bellis, Michael D.; Nooner, Kate B.; Nagel, Bonnie J.

    2017-01-01

    During adolescence, problems reflecting cognitive, behavioral and affective dysregulation, such as inattention and emotional dyscontrol, have been observed to be associated with substance use disorder (SUD) risks and outcomes. Prior studies have typically been with small samples, and have typically not included comprehensive measurement of executive dysfunction domains. The relationships of executive dysfunction in daily life with performance based testing of cognitive skills and structural brain characteristics, thought to be the basis for executive functioning, have not been definitively determined. The aims of this study were to determine the relationships between executive dysfunction in daily life, measured by the Behavior Rating Inventory of Executive Function (BRIEF), cognitive skills and structural brain characteristics, and SUD risks, including a global SUD risk indicator, sleep quality, and risky alcohol and cannabis use. In addition to bivariate relationships, multivariate models were tested. The subjects (n = 817; ages 12 through 21) were participants in the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) study. The results indicated that executive dysfunction was significantly related to SUD risks, poor sleep quality, risky alcohol use and cannabis use, and was not significantly related to cognitive skills or structural brain characteristics. In multivariate models, the relationship between poor sleep quality and risky substance use was mediated by executive dysfunction. While these cross-sectional relationships need to be further examined in longitudinal analyses, the results suggest that poor sleep quality and executive dysfunction may be viable preventive intervention targets to reduce adolescent substance use. PMID:29180956

  1. Unique Influences of Adolescent Antecedents on Adult Borderline Personality Disorder Features

    PubMed Central

    Stepp, Stephanie D.; Olino, Thomas M.; Klein, Daniel N.; Seeley, John R.; Lewinsohn, Peter M.

    2013-01-01

    There is a dearth of prospective information regarding adolescent precursors of borderline personality disorder (BPD). This study aims to determine the unique associations between early maladaptive family functioning, parental psychiatric diagnoses, proband early-onset psychiatric diagnosis and BPD symptoms in adulthood using an existing longitudinal study. Participants were randomly selected from nine high schools in western Oregon. A total of 1,709 students (ages 14-18 years) completed two assessments during adolescence. All adolescents with a history of a depressive disorder (n = 360) or a history of non-mood disorders (n = 284), and a random sample of adolescents with no history of psychopathology (n = 457) were invited to participate in a third and fourth evaluation when participants were on average 24 years and 30 years, respectively. Biological parents were interviewed at the third assessment. The multivariate model with all early risk factors found that maternal-child discord (p < .05), maternal BPD (p < .05), paternal Substance Use Disorder (SUD) (p < .05), and proband depression (p < .05), SUD (p < .001), and suicidality (p < .05) were associated with later BPD symptoms. Maternal SUD and proband anxiety, Conduct Disorder/Oppositional Defiant Disorder, and Attention Deficit Hyperactivity Disorder were also associated with proband BPD symptoms in univariate analyses, but were no longer significant when the other risk factors were included in the model. Multivariate assessment models are needed to identify unique risk factors for Borderline Personality Disorder. This will enhance the efficiency of screening efforts for early detection of risk. PMID:23397935

  2. Cardiorespiratory Fitness and Highly Sensitive Cardiac Troponin Levels in a Preventive Medicine Cohort.

    PubMed

    DeFina, Laura F; Willis, Benjamin L; Radford, Nina B; Christenson, Robert H; deFilippi, Christopher R; de Lemos, James A

    2016-11-28

    Cardiorespiratory fitness (CRF) and highly sensitive cardiac troponin T (hs-cTnT) are associated with risk of all-cause and cardiovascular mortality as well as incident heart failure. A link of low CRF to subclinical cardiac injury may explain this association. We hypothesized that CRF would be inversely associated with hs-cTnT measured in healthy adults over age 50. We evaluated 2498 participants (24.7% female, mean age 58.7 years) from the Cooper Center Longitudinal Study between August 2008 and January 2012. Plasma specimens obtained shortly before CRF estimates by Balke treadmill testing were used for hs-cTnT assays. CRF was grouped into low CRF (category 1), moderate CRF (categories 2-3), and high CRF (categories 4-5). Multivariable logistic regression was used to estimate the association of CRF with hs-cTnT. The prevalence of measurable hs-cTnT (≥3 ng/L) was 78.5%. In multivariable analyses, low-fit individuals were significantly more likely than high-fit individuals to have elevated hs-cTnT (≥14 ng/L) (odds ratio 2.47, 95% CI 1.10-5.36). In healthy older adults, CRF is inversely associated with hs-cTnT level adjusted for other risk factors. Prospective studies are needed to evaluate whether improving CRF is effective in preventing subclinical cardiac injury. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  3. Biodemographic Modeling of the Links Between Fertility Motivation and Fertility Outcomes in the NLSY79

    PubMed Central

    MILLER, WARREN B.; BARD, DAVID E.; PASTA, DAVID J.; RODGERS, JOSEPH LEE

    2010-01-01

    In spite of long-held beliefs that traits related to reproductive success tend to become fixed by evolution with little or no genetic variation, there is now considerable evidence that the natural variation of fertility within populations is genetically influenced and that a portion of that influence is related to the motivational precursors to fertility. We conduct a two-stage analysis to examine these inferences in a time-ordered multivariate context. First, using data from the National Longitudinal Survey of Youth, 1979, and LISREL analysis, we develop a structural equation model in which five hypothesized motivational precursors to fertility, measured in 1979–1982, predict both a child-timing and a child-number outcome, measured in 2002. Second, having chosen two time-ordered sequences of six variables from the SEM to represent our phenotypic models, we use Mx to conduct both univariate and multivariate behavioral genetic analyses with the selected variables. Our results indicate that one or more genes acting within a gene network have additive effects that operate through child-number desires to affect both the timing of the next child born and the final number of children born, that one or more genes acting through a separate network may have additive effects operating through gender role attitudes to produce downstream effects on the two fertility outcomes, and that no genetic variance is associated with either child-timing intentions or educational intentions. PMID:20608103

  4. Salivary Telomere Length and Lung Function in Adolescents Born Very Preterm: A Prospective Multicenter Study.

    PubMed

    Hadchouel, Alice; Marchand-Martin, Laetitia; Franco-Montoya, Marie-Laure; Peaudecerf, Laetitia; Ancel, Pierre-Yves; Delacourt, Christophe

    2015-01-01

    Preterm birth is associated with abnormal respiratory functions throughout life. The mechanisms underlying these long-term consequences are still unclear. Shortening of telomeres was associated with many conditions, such as chronic obstructive pulmonary disease. We aimed to search for an association between telomere length and lung function in adolescents born preterm. Lung function and telomere length were measured in 236 adolescents born preterm and 38 born full-term from the longitudinal EPIPAGE cohort. Associations between telomere length and spirometric indices were tested in univariate and multivariate models accounting for confounding factors in the study population. Airflows were significantly lower in adolescents born preterm than controls; forced expiratory volume in one second was 12% lower in the extremely preterm born group than controls (p<0.001). Lower birth weight, bronchopulmonary dysplasia and postnatal sepsis were significantly associated with lower airflow values. Gender was the only factor that was significantly associated with telomere length. Telomere length correlated with forced expiratory flow 25-75 in the extremely preterm adolescent group in univariate and multivariate analyses (p = 0.01 and p = 0.02, respectively). We evidenced an association between telomere length and abnormal airflow in a population of adolescents born extremely preterm. There was no evident association with perinatal events. This suggests other involved factors, such as a continuing airway oxidative stress leading to persistent inflammation and altered lung function, ultimately increasing susceptibility to chronic obstructive pulmonary disease.

  5. Relationship Between Urban Sprawl and Weight of United States Youth

    PubMed Central

    Ewing, Reid; Brownson, Ross C.; Berrigan, David

    2007-01-01

    Background Among United States youth there is an obesity epidemic with potential lifelong health implications. To date, relationships between the built environment and body mass index (BMI) have not been evaluated for youth, and have not been evaluated longitudinally. Objective To determine if urban sprawl is associated with BMI for U.S. youth. Method Using data from the 1997 National Longitudinal Survey of Youth (NLSY97), both cross-sectional and longitudinal analyses were conducted. Hierarchical modeling was used to relate characteristics of individuals, households, and places to BMI. Individual and household data were extracted from the NLSY97. The independent variable of interest was the county sprawl index, which was derived with principal components analyses from census and other data. Results In a cross-sectional analysis, the likelihood of U.S. adolescents (aged 12–17 years) being overweight or at risk of overweight (≥85th percentile relative to the Centers for Disease Control [CDC] growth charts) was associated with county sprawl (p=0.022). In another cross-sectional analysis, after controlling for sociodemographic and behavioral covariates, the likelihood of young adults (aged 18–23 years) being obese was also associated with county sprawl (p=0.048). By contrast, in longitudinal analyses, BMI growth curves for individual youth over the 7 years of NLSY97, and BMI changes for individual youth who moved between counties, were not related to county sprawl (although coefficient signs were as expected). Conclusions Cross-sectional analyses suggest that urban form is associated with overweight among U.S. youth. The strength of these relationships proved comparable to those previously reported for adults. Longitudinal analyses show no such relationship. It is unclear why these approaches give different results, but sample sizes, latent effects, and confounders may contribute. PMID:17169708

  6. Relationship between urban sprawl and weight of United States youth.

    PubMed

    Ewing, Reid; Brownson, Ross C; Berrigan, David

    2006-12-01

    Among United States youth there is an obesity epidemic with potential life-long health implications. To date, relationships between the built environment and body mass index (BMI) have not been evaluated for youth, and have not been evaluated longitudinally. To determine if urban sprawl is associated with BMI for U.S. youth. Using data from the 1997 National Longitudinal Survey of Youth (NLSY97), both cross-sectional and longitudinal analyses were conducted. Hierarchical modeling was used to relate characteristics of individuals, households, and places to BMI. Individual and household data were extracted from the NLSY97. The independent variable of interest was the county sprawl index, which was derived with principal components analyses from census and other data. In a cross-sectional analysis, the likelihood of U.S. adolescents (aged 12-17 years) being overweight or at risk of overweight (> or =85th percentile relative to the Centers for Disease Control growth charts) was associated with county sprawl (p=0.022). In another cross-sectional analysis, after controlling for sociodemographic and behavioral covariates, the likelihood of young adults (aged 18-23 years) being obese was also associated with county sprawl (p=0.048). By contrast, in longitudinal analyses, BMI growth curves for individual youth over the 7 years of NLSY97, and BMI changes for individual youth who moved between counties, were not related to county sprawl (although coefficient signs were as expected). Cross-sectional analyses suggest that urban form is associated with being overweight among U.S. youth. The strength of these relationships proved comparable to those previously reported for adults. Longitudinal analyses show no such relationship. It is unclear why these approaches give different results, but sample sizes, latent effects, and confounders may contribute.

  7. Mediator and moderator effects in developmental and behavioral pediatric research.

    PubMed

    Rose, Brigid M; Holmbeck, Grayson N; Coakley, Rachael Millstein; Franks, Elizabeth A

    2004-02-01

    The terms mediation and moderation are defined and clarified with particular emphasis on the role of mediational and moderational analyses in developmental and behavioral pediatric research. The article highlights the applicability of mediational and moderational analyses to longitudinal, intervention, and risk and protective factor research, and it provides basic information about how these analyses might be conducted. Also included is a discussion of various ways that both mediator and moderator variables can be incorporated into a single model. The article concludes with extended examples of both types of analyses using a longitudinal pediatric study for illustration. The article provides recommendations for applying mediational and moderational research in clinical practice.

  8. The association between modifiable well-being risks and productivity: a longitudinal study in pooled employer sample.

    PubMed

    Shi, Yuyan; Sears, Lindsay E; Coberley, Carter R; Pope, James E

    2013-04-01

    To examine the longitudinal relationship between modifiable well-being risks and productivity. A total of 19,121 employees from five employers participated in baseline and follow-up well-being assessment surveys. Multivariate regressions assessed whether changes in absenteeism, presenteeism, and job performance were associated with changes in 19 modifiable well-being risks. Over time, a 5% reduction in total count of well-being risks was significantly associated with 0.74% decrease in absenteeism, 2.38% decrease in presenteeism, and 0.24% increase in performance. High blood pressure, recurring pain, unhealthy diet, inadequate exercise, poor emotional health, poor supervisor relationship, not utilizing strengths doing job, and organization unsupportive of well-being had greater independent contributions in explaining productivity impairment. The often-ignored well-being risks such as work-related and financial health risks provided incremental explanation of longitudinal productivity variations beyond traditional measures of health-related risks.

  9. High-Intensity Cannabis Use And HIV Clinical Outcomes Among HIV-Positive People Who Use Illicit Drugs in Vancouver, Canada

    PubMed Central

    Lake, Stephanie; Kerr, Thomas; Capler, Rielle; Shoveller, Jeannie; Montaner, Julio; Milloy, M-J

    2017-01-01

    Background Reforms to the legal status of medical and non-medical cannabis are underway in many jurisdictions, including Canada, as are renewed efforts to scale-up HIV treatment-as-prevention (TasP) initiatives. It has been suggested that high-intensity cannabis use may be associated with sub-optimal HIV treatment outcomes. Thus, using data from a setting with a community-wide treatment-as-prevention (TasP) initiative coinciding with increasing access to medical cannabis, we sought to investigate the possible impact of high-intensity cannabis use on HIV clinical outcomes. Methods Data was derived from the ACCESS study, a prospective cohort of HIV-positive people who use illicit drugs (PWUD) in Vancouver, Canada. Cohort data was confidentially linked to comprehensive clinical profiles, including records of all antiretroviral therapy (ART) dispensations and longitudinal plasma HIV-1 RNA viral load (VL) monitoring. We used generalized estimating equations (GEEs) to estimate the longitudinal bivariable and multivariable relationships between at least daily cannabis use and two key clinical outcomes: overall engagement in ART care, and achieving a non-detectable VL among ART-exposed participants. Results Between December 2005 and June 2015, 874 HIV-positive PWUD (304 [35%] non-male) were included in this study. In total, 788 (90%) were engaged in HIV care at least once over the study period, of whom 670 (85%) achieved non-detectable VL at least once. In multivariable analyses, ≥ daily cannabis use did not predict lower odds of ART care (Adjusted Odds Ratio [AOR]: 1.02, 95% confidence interval [CI]: 0.77–1.36) or VL non-detectability among ART-exposed (AOR: 0.96, 95% CI: 0.75–1.21). Conclusion Our results showed no statistically significant impact of daily cannabis use on the likelihood of ART care or VL non-detectability among ART-exposed HIV-positive PWUD. These findings are reassuring in light of the impending legalization of cannabis in Canada and ongoing efforts to expand TasP initiatives. PMID:28336000

  10. The Combined Quantification and Interpretation of Multiple Quantitative Magnetic Resonance Imaging Metrics Enlightens Longitudinal Changes Compatible with Brain Repair in Relapsing-Remitting Multiple Sclerosis Patients.

    PubMed

    Bonnier, Guillaume; Maréchal, Benedicte; Fartaria, Mário João; Falkowskiy, Pavel; Marques, José P; Simioni, Samanta; Schluep, Myriam; Du Pasquier, Renaud; Thiran, Jean-Philippe; Krueger, Gunnar; Granziera, Cristina

    2017-01-01

    Quantitative and semi-quantitative MRI (qMRI) metrics provide complementary specificity and differential sensitivity to pathological brain changes compatible with brain inflammation, degeneration, and repair. Moreover, advanced magnetic resonance imaging (MRI) metrics with overlapping elements amplify the true tissue-related information and limit measurement noise. In this work, we combined multiple advanced MRI parameters to assess focal and diffuse brain changes over 2 years in a group of early-stage relapsing-remitting MS patients. Thirty relapsing-remitting MS patients with less than 5 years disease duration and nine healthy subjects underwent 3T MRI at baseline and after 2 years including T1, T2, T2* relaxometry, and magnetization transfer imaging. To assess longitudinal changes in normal-appearing (NA) tissue and lesions, we used analyses of variance and Bonferroni correction for multiple comparisons. Multivariate linear regression was used to assess the correlation between clinical outcome and multiparametric MRI changes in lesions and NA tissue. In patients, we measured a significant longitudinal decrease of mean T2 relaxation times in NA white matter ( p  = 0.005) and a decrease of T1 relaxation times in the pallidum ( p  < 0.05), which are compatible with edema reabsorption and/or iron deposition. No longitudinal changes in qMRI metrics were observed in controls. In MS lesions, we measured a decrease in T1 relaxation time ( p -value < 2.2e-16) and a significant increase in MTR ( p -value < 1e-6), suggesting repair mechanisms, such as remyelination, increased axonal density, and/or a gliosis. Last, the evolution of advanced MRI metrics-and not changes in lesions or brain volume-were correlated to motor and cognitive tests scores evolution (Adj- R 2  > 0.4, p  < 0.05). In summary, the combination of multiple advanced MRI provided evidence of changes compatible with focal and diffuse brain repair at early MS stages as suggested by histopathological studies.

  11. Exploring Structural Dynamics within and between Sensory and Intellectual Functioning in Old and Very Old Age: Longitudinal Evidence from the Berlin Aging Study

    ERIC Educational Resources Information Center

    Ghisletta, Paolo; Lindenberger, Ulman

    2005-01-01

    Cross-sectional and longitudinal analyses of age-heterogeneous samples have revealed correlational links between and within intellectual, sensory, and sensorimotor domains. Due to basic limitations of cross-sectional designs and a reluctance to disentangle antecedent-consequent relations in longitudinal designs, the functional significance and…

  12. The impact of parent-child interaction on brain structures: cross-sectional and longitudinal analyses.

    PubMed

    Takeuchi, Hikaru; Taki, Yasuyuki; Hashizume, Hiroshi; Asano, Kohei; Asano, Michiko; Sassa, Yuko; Yokota, Susumu; Kotozaki, Yuka; Nouchi, Rui; Kawashima, Ryuta

    2015-02-04

    There is a vast amount of evidence from psychological studies that the amount of parent-child interaction affects the development of children's verbal skills and knowledge. However, despite the vast amount of literature, brain structural development associated with the amount of parent-child interaction has never been investigated. In the present human study, we used voxel-based morphometry to measure regional gray matter density (rGMD) and examined cross-sectional correlations between the amount of time spent with parents and rGMD among 127 boys and 135 girls. We also assessed correlations between the amount of time spent with parents and longitudinal changes that occurred a few years later among 106 boys and 102 girls. After correcting for confounding factors, we found negative effects of spending time with parents on rGMD in areas in the bilateral superior temporal gyrus (STG) via cross-sectional analyses as well as in the contingent areas of the right STG. We also confirmed positive effects of spending time with parents on the Verbal Comprehension score in cross-sectional and longitudinal analyses. rGMD in partly overlapping or contingent areas of the right STG was negatively correlated with age and the Verbal Comprehension score in cross-sectional analyses. Subsequent analyses revealed verbal parent-child interactions have similar effects on Verbal Comprehension scores and rGMD in the right STG in both cross-sectional and longitudinal analyses. These findings indicate that parent-child interactions affect the right STG, which may be associated with verbal skills. Copyright © 2015 the authors 0270-6474/15/352233-13$15.00/0.

  13. Nursing and midwifery students' perceptions of spirituality, spiritual care, and spiritual care competency: A prospective, longitudinal, correlational European study.

    PubMed

    Ross, Linda; McSherry, Wilfred; Giske, Tove; van Leeuwen, René; Schep-Akkerman, Annemiek; Koslander, Tiburtius; Hall, Jenny; Steenfeldt, Vibeke Østergaard; Jarvis, Paul

    2018-08-01

    Nurses and midwives care for people at some of the most vulnerable moments of their lives, so it is essential that they have the skills to give care which is compassionate, dignified, holistic and person-centred. Holistic care includes spiritual care which is concerned with helping people whose beliefs, values and sense of meaning, purpose and connection is challenged by birth, illness or death. Spiritual care is expected of nurses/midwives but they feel least prepared for this part of their role. How nursing and midwifery students can be prepared for spiritual care is the focus of this study. 1. To describe undergraduate nursing and midwifery student's perceptions of spirituality/spiritual care, their perceived competence in giving spiritual care and how these perceptions change over time. 2. To explore factors contributing to development of spiritual care competency. Prospective, longitudinal, multinational, correlational survey design. A convenience sample of 2193 undergraduate nursing and midwifery students (69% response rate, dropping to 33%) enrolled at 21 universities in eight countries completed questionnaires capturing demographic data (purpose designed questionnaire) and measuring perception of spirituality/spiritual care (SSCRS), spiritual care competency (SCCS), spiritual wellbeing (JAREL) and spiritual attitude and involvement (SAIL) on 4 occasions (start of course n = 2193, year 2 n = 1182, year 3 n = 736, end of course n = 595) between 2011 and 2015. Data were analysed using descriptive, bivariate and multivariate analyses as appropriate. Perceived competency increased significantly over the course of students' study which they attributed to caring for patients, events in their own lives and teaching/discussion in university. Two factors were significantly correlated with perceived spiritual care competency: perception of spirituality/spiritual care, where a broad view was preferable, and personal spirituality, where high spiritual wellbeing (JAREL) and spiritual attitude and involvement (SAIL) scores were preferable. We have provided the first international evidence that perceived spiritual care competence is developed in undergraduate nursing and midwifery students and that students' perceptions of spirituality and personal spirituality contribute to that development. Implications for teaching and learning and student selection are discussed. The study is limited by attrition which is common in longitudinal research. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Longitudinal study examining the neurotoxicity of occupational exposure to aluminium-containing welding fumes.

    PubMed

    Buchta, M; Kiesswetter, E; Otto, A; Schaller, K H; Seeber, A; Hilla, W; Windorfer, K; Stork, J; Kuhlmann, A; Gefeller, O; Letzel, S

    2003-09-01

    The neurotoxicity of occupational exposure to aluminium (Al)-containing welding fumes has been discussed with controversial results. The aim of the longitudinal study was to examine a group of Al welders for significant central nervous changes in comparison with a non-exposed cohort. A group of 98 Al welders (mean age 37 years) in the car-body construction industry, with a median of 6 years of occupational exposure to Al welding fumes, and an education-matched, gender-matched, age-matched control group of 50 car-production workers (mean age 36 years) at the same plant, were included in this longitudinal study. Two cross-sectional studies were done in 1999 and 2001. In the second cross-sectional study 97 welders and 50 controls could be examined. The examination programme consisted, for example, of a standardised anamnesis, focussing on occupational history, education, illnesses, medication, accidents and current alcohol consumption, a physical examination that included neurological status, and the assessment of Al concentration in plasma and urine. The neurobehavioral methods included a symptom questionnaire, modified Q16, and computerised and non-computerised tests: psychomotor performance (steadiness, line tracing, aiming, tapping), verbal intelligence (WST), simple reaction time, digit span, block design (HAWIE), symbol-digit substitution, digit span, switching attention (European neurobehavioral evaluation system, EURO-NES), and standard progressive matrices. The data were analysed by multivariate analysis of covariance (MANCOVA) for repeated measurements with covariates age, education, and carbohydrate-deficient transferrin in plasma (CDT). RESULTS. The median Al urine concentration (mean preshift/postshift) was 52.4 microg/g creatinine (2001) and 57.6 microg/g creatinine (1999). Median respirable air dust was 0.67 mg/m(3) (2001) and 0.47 mg/m(3) (1999). Welders and controls did not report significantly more symptoms in the modified Q16. Furthermore, no significant differences in psychomotor performance and other neurobehavioral tasks, except for reaction time, were seen between welders and non-welders. Regression analyses reveal a significant relationship between reaction time and Al excretion in urine that was confounded by other factors. At present the outcome for reaction time has to be interpreted as a single result. However, as the modified Q16 questionnaire and the rest of the psychomotor performance showed no significant changes, the next cross-sectional study, in 2003, will provide further information on which a final conclusion can be based.

  15. Dietary inflammatory index and telomere length in subjects with a high cardiovascular disease risk from the PREDIMED-NAVARRA study: cross-sectional and longitudinal analyses over 5 y1

    PubMed Central

    García-Calzón, Sonia; Zalba, Guillermo; Ruiz-Canela, Miguel; Shivappa, Nitin; Hébert, James R; Martínez, J Alfredo; Fitó, Montserrat; Gómez-Gracia, Enrique; Martínez-González, Miguel A; Marti, Amelia

    2015-01-01

    Background: Dietary factors can affect telomere length (TL), a biomarker of aging, through oxidation and inflammation-related mechanisms. A Dietary Inflammatory Index (DII) could help to understand the effect of the inflammatory potential of the diet on telomere shortening. Objective: This study aimed to determine the association of the DII with TL and to examine whether diet-associated inflammation could modify the telomere attrition rate after a 5-y follow-up of a Mediterranean dietary intervention. Design: This was a prospective study of 520 participants at high cardiovascular disease risk (mean ± SD age: 67.0 ± 6.0 y, 45% males) from the PREDIMED-NAVARRA (PREvención con DIeta MEDiterránea-NAVARRA) trial. Leukocyte TL was measured by quantitative real-time polymerase chain reaction at baseline and after 5 y of follow-up. The DII was calculated from self-reported data by using a validated 137-item food-frequency questionnaire. Results: Longer telomeres at baseline were found in participants who had a more anti-inflammatory diet (lowest DII score) (P-trend = 0.012). Longitudinal analyses further showed that a greater anti-inflammatory potential of the diet (i.e., a decrease in the DII) could significantly slow down the rate of telomere shortening. Moreover, the multivariable-adjusted OR for short telomeres (z score ≤20th percentile) was 1.80 (95% CI: 1.03, 3.17) in a comparison between the highest (proinflammatory) and the lowest (anti-inflammatory) DII tertiles. Similarly, a greater DII (greatest proinflammatory values) after a 5-y follow-up was associated with almost a 2-fold higher risk of accelerated telomere attrition compared with the highest decrease in DII (greatest anti-inflammatory values) during this period (P-trend = 0.025). Conclusions: This study showed both cross-sectional and longitudinal associations between the inflammatory potential of the diet and telomere shortening in subjects with a high cardiovascular disease risk. Our findings are consistent with, but do not show, a beneficial effect of adherence to an anti-inflammatory diet on aging and health by slowing down telomere shortening. These results suggest that diet might play a key role as a determinant of TL through proinflammatory or anti-inflammatory mechanisms. This trial was registered at controlled-trials.com as ISRCTN35739639. PMID:26354530

  16. Dietary inflammatory index and telomere length in subjects with a high cardiovascular disease risk from the PREDIMED-NAVARRA study: cross-sectional and longitudinal analyses over 5 y.

    PubMed

    García-Calzón, Sonia; Zalba, Guillermo; Ruiz-Canela, Miguel; Shivappa, Nitin; Hébert, James R; Martínez, J Alfredo; Fitó, Montserrat; Gómez-Gracia, Enrique; Martínez-González, Miguel A; Marti, Amelia

    2015-10-01

    Dietary factors can affect telomere length (TL), a biomarker of aging, through oxidation and inflammation-related mechanisms. A Dietary Inflammatory Index (DII) could help to understand the effect of the inflammatory potential of the diet on telomere shortening. This study aimed to determine the association of the DII with TL and to examine whether diet-associated inflammation could modify the telomere attrition rate after a 5-y follow-up of a Mediterranean dietary intervention. This was a prospective study of 520 participants at high cardiovascular disease risk (mean ± SD age: 67.0 ± 6.0 y, 45% males) from the PREDIMED-NAVARRA (PREvención con DIeta MEDiterránea-NAVARRA) trial. Leukocyte TL was measured by quantitative real-time polymerase chain reaction at baseline and after 5 y of follow-up. The DII was calculated from self-reported data by using a validated 137-item food-frequency questionnaire. Longer telomeres at baseline were found in participants who had a more anti-inflammatory diet (lowest DII score) (P-trend = 0.012). Longitudinal analyses further showed that a greater anti-inflammatory potential of the diet (i.e., a decrease in the DII) could significantly slow down the rate of telomere shortening. Moreover, the multivariable-adjusted OR for short telomeres (z score ≤20th percentile) was 1.80 (95% CI: 1.03, 3.17) in a comparison between the highest (proinflammatory) and the lowest (anti-inflammatory) DII tertiles. Similarly, a greater DII (greatest proinflammatory values) after a 5-y follow-up was associated with almost a 2-fold higher risk of accelerated telomere attrition compared with the highest decrease in DII (greatest anti-inflammatory values) during this period (P-trend = 0.025). This study showed both cross-sectional and longitudinal associations between the inflammatory potential of the diet and telomere shortening in subjects with a high cardiovascular disease risk. Our findings are consistent with, but do not show, a beneficial effect of adherence to an anti-inflammatory diet on aging and health by slowing down telomere shortening. These results suggest that diet might play a key role as a determinant of TL through proinflammatory or anti-inflammatory mechanisms. This trial was registered at controlled-trials.com as ISRCTN35739639. © 2015 American Society for Nutrition.

  17. Multivariate meta-analysis using individual participant data.

    PubMed

    Riley, R D; Price, M J; Jackson, D; Wardle, M; Gueyffier, F; Wang, J; Staessen, J A; White, I R

    2015-06-01

    When combining results across related studies, a multivariate meta-analysis allows the joint synthesis of correlated effect estimates from multiple outcomes. Joint synthesis can improve efficiency over separate univariate syntheses, may reduce selective outcome reporting biases, and enables joint inferences across the outcomes. A common issue is that within-study correlations needed to fit the multivariate model are unknown from published reports. However, provision of individual participant data (IPD) allows them to be calculated directly. Here, we illustrate how to use IPD to estimate within-study correlations, using a joint linear regression for multiple continuous outcomes and bootstrapping methods for binary, survival and mixed outcomes. In a meta-analysis of 10 hypertension trials, we then show how these methods enable multivariate meta-analysis to address novel clinical questions about continuous, survival and binary outcomes; treatment-covariate interactions; adjusted risk/prognostic factor effects; longitudinal data; prognostic and multiparameter models; and multiple treatment comparisons. Both frequentist and Bayesian approaches are applied, with example software code provided to derive within-study correlations and to fit the models. © 2014 The Authors. Research Synthesis Methods published by John Wiley & Sons, Ltd.

  18. Long-Term Athletic Development in Youth Alpine Ski Racing: The Effect of Physical Fitness, Ski Racing Technique, Anthropometrics and Biological Maturity Status on Injuries

    PubMed Central

    Müller, Lisa; Hildebrandt, Carolin; Müller, Erich; Fink, Christian; Raschner, Christian

    2017-01-01

    Alpine ski racing is known to be a sport with a high risk of injuries. Because most studies have focused mainly on top-level athletes and on traumatic injuries, limited research exists about injury risk factors among youth ski racers. The aim of this study was to determine the intrinsic risk factors (anthropometrics, biological maturity, physical fitness, racing technique) for injury among youth alpine ski racers. Study participants were 81 youth ski racers attending a ski boarding school (50 males, 31 females; 9–14 years). A prospective longitudinal cohort design was used to monitor sports-related risk factors over two seasons and traumatic (TI) and overuse injuries (OI). At the beginning of the study, anthropometric characteristics (body height, body weight, sitting height, body mass index); biological maturity [status age at peak height velocity (APHV)]; physical performance parameters related to jump coordination, maximal leg and core strength, explosive and reactive strength, balance and endurance; and ski racing technique were assessed. Z score transformations normalized the age groups. Multivariate binary logistic regression (dependent variable: injury yes/no) and multivariate linear regression analyses (dependent variable: injury severity in total days of absence from training) were calculated. T-tests and multivariate analyses of variance were used to reveal differences between injured and non-injured athletes and between injury severity groups. The level of significance was set to p < 0.05. Relatively low rates of injuries were reported for both traumatic (0.63 TI/athlete) and overuse injuries (0.21 OI/athlete). Athletes with higher body weight, body height, and sitting height; lower APHV values; better core flexion strength; smaller core flexion:extension strength ratio; shorter drop jump contact time; and higher drop jump reactive strength index were at a lower injury risk or more vulnerable for fewer days of absence from training. However, significant differences between injured and non-injured athletes were only observed with respect to the drop jump reactive strength index. Regular documentation of anthropometric characteristics, biological maturity and physical fitness parameters is crucial to help to prevent injury in youth ski racing. The present findings suggest that neuromuscular training should be incorporated into the training regimen of youth ski racers to prevent injuries. PMID:28912731

  19. Long-Term Athletic Development in Youth Alpine Ski Racing: The Effect of Physical Fitness, Ski Racing Technique, Anthropometrics and Biological Maturity Status on Injuries.

    PubMed

    Müller, Lisa; Hildebrandt, Carolin; Müller, Erich; Fink, Christian; Raschner, Christian

    2017-01-01

    Alpine ski racing is known to be a sport with a high risk of injuries. Because most studies have focused mainly on top-level athletes and on traumatic injuries, limited research exists about injury risk factors among youth ski racers. The aim of this study was to determine the intrinsic risk factors (anthropometrics, biological maturity, physical fitness, racing technique) for injury among youth alpine ski racers. Study participants were 81 youth ski racers attending a ski boarding school (50 males, 31 females; 9-14 years). A prospective longitudinal cohort design was used to monitor sports-related risk factors over two seasons and traumatic (TI) and overuse injuries (OI). At the beginning of the study, anthropometric characteristics (body height, body weight, sitting height, body mass index); biological maturity [status age at peak height velocity (APHV)]; physical performance parameters related to jump coordination, maximal leg and core strength, explosive and reactive strength, balance and endurance; and ski racing technique were assessed. Z score transformations normalized the age groups. Multivariate binary logistic regression (dependent variable: injury yes/no) and multivariate linear regression analyses (dependent variable: injury severity in total days of absence from training) were calculated. T -tests and multivariate analyses of variance were used to reveal differences between injured and non-injured athletes and between injury severity groups. The level of significance was set to p < 0.05. Relatively low rates of injuries were reported for both traumatic (0.63 TI/athlete) and overuse injuries (0.21 OI/athlete). Athletes with higher body weight, body height, and sitting height; lower APHV values; better core flexion strength; smaller core flexion:extension strength ratio; shorter drop jump contact time; and higher drop jump reactive strength index were at a lower injury risk or more vulnerable for fewer days of absence from training. However, significant differences between injured and non-injured athletes were only observed with respect to the drop jump reactive strength index. Regular documentation of anthropometric characteristics, biological maturity and physical fitness parameters is crucial to help to prevent injury in youth ski racing. The present findings suggest that neuromuscular training should be incorporated into the training regimen of youth ski racers to prevent injuries.

  20. Differential Responsiveness to Cigarette Price by Education and Income among Adult Urban Chinese Smokers

    PubMed Central

    Huang, Jidong; Zheng, Rong; Chaloupka, Frank J.; Fong, Geoffrey T.; Jiang, Yuan

    2015-01-01

    Background There are few studies that examine the impact of tobacco tax and price policies in China. In addition, very little is known about the differential responses to tax and price increases based on socioeconomic status in China. Objective The goal of this study is to estimate the conditional cigarette consumption price elasticity among adult urban smokers in China using individual level longitudinal survey data. We also examine the differential responses to cigarette price increases among groups with different income and/or educational levels. Methods Multivariate analyses using the general estimating equations (GEE) method were conducted to estimate the conditional cigarette demand price elasticity using data from the International Tobacco Control (ITC) China Survey, a longitudinal survey of adult smokers in seven cities in China. The first three waves of the ITC China Survey data were used in this analysis. Analyses based on subsample by education and income were conducted. Findings Our results show that overall conditional cigarette demand price elasticity ranges from −0.12 to −0.14, implying a 10% increase in cigarette price would result in a reduction in cigarette consumption among adult urban Chinese smokers by 1.2% to 1.4%. No differential responses to cigarette price increase were found across education levels. The price elasticity estimates do not differ between high income smokers and medium income smokers. However, cigarette consumption among low income smokers did not seem to decrease after a price increase, at least among those who continued to smoke. Conclusion Relative to many other low- and middle-income countries, cigarette consumption among Chinese adult smokers is not very sensitive to changes in cigarette prices. The total impact of cigarette price increase would be larger if its impact on smoking initiation and cessation, as well as the price-reducing behaviors such as brand switching and trading down, were taken into account. PMID:25855640

  1. Association Between Global Longitudinal Strain and Cardiovascular Events in Patients With Left Bundle Branch Block Assessed Using Two-Dimensional Speckle-Tracking Echocardiography.

    PubMed

    Hwang, In-Chang; Cho, Goo-Yeong; Yoon, Yeonyee E; Park, Jin Joo

    2018-01-01

    The prognostic value of left ventricular (LV) global strain and twist in patients with left bundle branch block (LBBB) is not fully investigated. The aim of this study was to investigate the association between myocardial strain and twist and cardiovascular events in patients with LBBB, as assessed using two-dimensional speckle-tracking echocardiography. A total of 269 patients with LBBB (mean age, 69.5 ± 10.9 years; 46.8% men) were retrospectively identified. Using speckle-tracking, LV global longitudinal strain (GLS), global circumferential strain, and twist were measured. Association between LV global function and a composite of cardiovascular mortality and hospitalization for heart failure was compared with clinical risk factors, LV ejection fraction (LVEF), and other echocardiographic parameters. During a median of 27.5 months (interquartile range, 12.8-43.9 months), the composite end point occurred in 55 patients (20.4%). In univariate analyses, diabetes mellitus, chronic kidney disease, ischemic etiology of LBBB, dilated left atrium, reduced LVEF, dilated left ventricle, and impaired LV global strain (GLS > -12.2%, global circumferential strain > -11.8%, and twist < 6.5°) showed associations with the composite end point. In multivariate analyses, GLS was significantly associated with the composite end point (adjusted hazard ratio, 4.697; 95% CI, 1.344-16.413; P = .015), whereas global circumferential strain, twist, and LVEF were not. GLS showed an additive association with poor prognosis over clinical risk factors and other echocardiographic parameters, including LVEF. Patients with preserved LVEFs (≥40%) but impaired GLS (>-12.2%) had a larger number of clinical events than those with impaired LVEFs but preserved GLS. Among patients with LBBB, GLS can provide better risk stratification than LVEF or other echocardiographic parameters. Copyright © 2017 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

  2. Advancing Concussion Assessment in Pediatrics (A-CAP): a prospective, concurrent cohort, longitudinal study of mild traumatic brain injury in children: study protocol

    PubMed Central

    Beauchamp, Miriam; Craig, William; Doan, Quynh; Zemek, Roger; Bjornson, Bruce H; Gravel, Jocelyn; Mikrogianakis, Angelo; Goodyear, Bradley; Abdeen, Nishard; Beaulieu, Christian; Dehaes, Mathieu; Deschenes, Sylvain; Harris, Ashley; Lebel, Catherine; Lamont, Ryan; Williamson, Tyler; Barlow, Karen Maria; Bernier, Francois; Brooks, Brian L; Emery, Carolyn; Freedman, Stephen B; Kowalski, Kristina; Mrklas, Kelly; Tomfohr-Madsen, Lianne; Schneider, Kathryn J

    2017-01-01

    Introduction Paediatric mild traumatic brain injury (mTBI) is a public health burden. Clinicians urgently need evidence-based guidance to manage mTBI, but gold standards for diagnosing and predicting the outcomes of mTBI are lacking. The objective of the Advancing Concussion Assessment in Pediatrics (A-CAP) study is to assess a broad pool of neurobiological and psychosocial markers to examine associations with postinjury outcomes in a large sample of children with either mTBI or orthopaedic injury (OI), with the goal of improving the diagnosis and prognostication of outcomes of paediatric mTBI. Methods and analysis A-CAP is a prospective, longitudinal cohort study of children aged 8.00–16.99 years with either mTBI or OI, recruited during acute emergency department (ED) visits at five sites from the Pediatric Emergency Research Canada network. Injury information is collected in the ED; follow-up assessments at 10 days and 3 and 6 months postinjury measure a variety of neurobiological and psychosocial markers, covariates/confounders and outcomes. Weekly postconcussive symptom ratings are obtained electronically. Recruitment began in September 2016 and will occur for approximately 24 months. Analyses will test the major hypotheses that neurobiological and psychosocial markers can: (1) differentiate mTBI from OI and (2) predict outcomes of mTBI. Models initially will focus within domains (eg, genes, imaging biomarkers, psychosocial markers), followed by multivariable modelling across domains. The planned sample size (700 mTBI, 300 OI) provides adequate statistical power and allows for internal cross-validation of some analyses. Ethics and dissemination The ethics boards at all participating institutions have approved the study and all participants and their parents will provide informed consent or assent. Dissemination will follow an integrated knowledge translation plan, with study findings presented at scientific conferences and in multiple manuscripts in peer-reviewed journals. PMID:28710227

  3. Universal Coverage without Universal Access: Institutional Barriers to Health Care among Women Sex Workers in Vancouver, Canada.

    PubMed

    Socías, M Eugenia; Shoveller, Jean; Bean, Chili; Nguyen, Paul; Montaner, Julio; Shannon, Kate

    2016-01-01

    Access to health care is a crucial determinant of health. Yet, even within settings that purport to provide universal health coverage (UHC), sex workers' experiences reveal systematic, institutionally ingrained barriers to appropriate quality health care. The aim of this study was to assess prevalence and correlates of institutional barriers to care among sex workers in a setting with UHC. Data was drawn from an ongoing community-based, prospective cohort of women sex workers in Vancouver, Canada (An Evaluation of Sex Workers' Health Access). Multivariable logistic regression analyses, using generalized estimating equations (GEE), were employed to longitudinally investigate correlates of institutional barriers to care over a 44-month follow-up period (January 2010-August 2013). In total, 723 sex workers were included, contributing to 2506 observations. Over the study period, 509 (70.4%) women reported one or more institutional barriers to care. The most commonly reported institutional barriers to care were long wait times (54.6%), limited hours of operation (36.5%), and perceived disrespect by health care providers (26.1%). In multivariable GEE analyses, recent partner- (adjusted odds ratio [AOR] = 1.46, % 95% Confidence Interval [CI] 1.10-1.94), workplace- (AOR = 1.31, 95% CI 1.05-1.63), and community-level violence (AOR = 1.41, 95% CI 1.04-1.92), as well as other markers of vulnerability, such as self-identification as a gender/sexual minority (AOR = 1.32, 95% CI 1.03-1.69), a mental illness diagnosis (AOR = 1.66, 95% CI 1.34-2.06), and lack of provincial health insurance card (AOR = 3.47, 95% CI 1.59-7.57) emerged as independent correlates of institutional barriers to health services. Despite Canada's UHC, women sex workers in Vancouver face high prevalence of institutional barriers to care, with highest burden among most marginalized women. These findings underscore the need to explore new models of care, alongside broader policy changes to fulfill sex workers' health and human rights.

  4. Oncologic relevance of magnetic resonance imaging-detected threatened mesorectal fascia for patients with mid or low rectal cancer: A longitudinal analysis before and after long-course, concurrent chemoradiotherapy.

    PubMed

    Son, Il Tae; Kim, Young Hoon; Lee, Kyoung Ho; Kang, Sung Il; Kim, Duck-Woo; Shin, Eun; Lee, Keun-Wook; Ahn, Soyeon; Kim, Jae-Sung; Kang, Sung-Bum

    2017-07-01

    The oncologic importance of threatened mesorectal fascia detected with magnetic resonance imaging is obscured by the heterogeneity of preoperative treatments. We evaluated the oncologic relevance of threatened mesorectal fascia detected with consecutive magnetic resonance imaging performed before and after long-course, concurrent chemoradiotherapy (LCRT) for mid or low rectal cancer. We evaluated 196 patients who underwent total mesorectal excision with LCRT. Threatened mesorectal fascia was defined as a shortest distance from tumor to mesorectal fascia of ≤ 1 mm on magnetic resonance imaging. Multivariate analyses for disease-free survival using magnetic resonance imaging-based parameters were conducted with a Cox proportional hazard model before and after LCRT, respectively. The pathologic positivity of the circumferential resection margin was greater for threatened mesorectal fascia than for clear mesorectal fascia (pre-LCRT, 14.8% vs 3.0%, P = .004; post-LCRT, 15.4% vs 4.5%, P = .025). At a median follow-up of 68 months, 3-year disease-free survival was worse for threatened mesorectal fascia than for clear mesorectal fascia (pre-LCRT, 77.0% vs 88.1%, P = .023; post-LCRT, 76.9% vs 86.6%, P = .029). On multivariate analyses, threatened mesorectal fascia on pre-LCRT magnetic resonance imaging was an independent factor for poor disease-free survival (hazard ratio = 2.153, 95% confidence interval, 1.07-4.32, P = .031), whereas threatened mesorectal fascia on post-LCRT magnetic resonance imaging was not (hazard ratio = 1.689, 95% confidence interval, 0.77-3.66, P = .189). This study confirms that magnetic resonance imaging-detected threatened mesorectal fascia predicts poor oncologic outcomes for mid or low rectal cancer and shows that the diagnostic performance of pre-LCRT magnetic resonance imaging is different from that of post-LCRT magnetic resonance imaging. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Childhood Internalizing and Externalizing Problems Predict the Onset of Clinical Panic Attacks over Adolescence: The TRAILS Study

    PubMed Central

    Mathyssek, Christina M.; Olino, Thomas M.; Verhulst, Frank C.; van Oort, Floor V. A.

    2012-01-01

    Background Panic attacks are a source of individual suffering and are an independent risk factor for later psychopathology. However, much less is known about risk factors for the development of panic attacks, particularly during adolescence when the incidence of panic attacks increases dramatically. We examined whether internalizing and externalizing problems in childhood predict the onset of panic attacks in adolescence. Method This study is part of the TRacking Adolescents’ Individual Lives Survey (TRAILS), a Dutch longitudinal population cohort study (N = 1,584). Internalizing and Externalizing Problems were collected using the Youth Self-Report (YSR) and the parent-report Child Behavior Checklist (CBCL) at baseline (age 10–12). At age 18–20, DSM-IV defined panic attacks since baseline were assessed with the Composite International Diagnostic Interview (CIDI). We investigated whether early adolescent Internalizing and Externalizing Problems predicted panic attacks between ages 10–20 years, using survival analysis in univariate and multivariate models. Results There were N = 314 (19.8%) cases who experienced at least one DSM-IV defined panic attack during adolescence and N = 18 (1.2%) who developed panic disorder during adolescence. In univariate analyses, CBCL Total Problems, Internalizing Problems and three of the eight syndrome scales predicted panic attack onset, while on the YSR all broad-band problem scales and each narrow-band syndrome scale predicted panic attack onset. In multivariate analyses, CBCL Social Problems (HR 1.19, p<.05), and YSR Thought Problems (HR 1.15, p<.05) and Social Problems (HR 1.26, p<.01) predicted panic attack onset. Conclusion Risk indicators of panic attack include the wide range of internalizing and externalizing problems. Yet, when adjusted for co-occurring problem behaviors, Social Problems were the most consistent risk factor for panic attack onsets in adolescence. PMID:23251576

  6. Patient expectations and experiences of multiple sclerosis interferon β-1a treatment: a longitudinal, observational study in routine UK clinical practice

    PubMed Central

    Syed, Mehmood; Rog, David; Parkes, Laura; Shepherd, Gillian L

    2014-01-01

    Background Premature discontinuation and poor treatment adherence are problems in chronic conditions, such as multiple sclerosis in which patients must take long-term treatment in order to receive maximum benefit from their medication. The Assessing needs In Multiple Sclerosis (AIMS) study explored factors related to premature treatment discontinuation and patients’ experiences of subcutaneous (sc) interferon (IFN) β-1a treatment in the UK. Methods A questionnaire-based survey was integrated into the Bupa Home Healthcare patient-support program, which delivers sc IFN β-1a to patients in their home. Data were collected via patient questionnaires incorporated into routine clinical care and administered upon registration of a new patient by the coordinator, following initial delivery of treatment, prior to each delivery during therapy and at the end of treatment. Univariate and multivariate analyses were performed to identify factors associated with premature discontinuation. Results Data were collected from 2,390 patients (1,267 new; 1,123 existing) from 59 UK prescribing centers (November 2006–April 2011). Following the first delivery of sc IFN β-1a, 94% (1,149/1,225) of patients had received training, and 73% (818/1,120) reported that they had no concerns. In total, 24% of new patients discontinued therapy by the end of the study. In the univariate model, none of the candidate variables tested were significant predictors of treatment discontinuation. The strongest predictors of discontinuation in multivariate analyses were lack of information prior to starting treatment and patients feeling unwell on treatment and geographic region (P<0.05 for each variable). Conclusion This study suggests that patients feeling well on treatment and provision of high-quality information are the main determinants of persistence with sc IFN β-1a therapy. A package of care that targets these issues should therefore be considered when initiating sc IFN β-1a therapy. PMID:24570582

  7. Follicle-stimulating hormone and bioavailable estradiol are less important than weight and race in determining bone density in younger postmenopausal women

    PubMed Central

    Preisser, J. S.; Hammett-Stabler, C. A.; Renner, J. B.; Rubin, J.

    2011-01-01

    Summary The association between follicle-stimulating hormone (FSH) and bone density was tested in 111 postmenopausal women aged 50–64 years. In the multivariable analysis, weight and race were important determinants of bone mineral density. FSH, bioavailable estradiol, and other hormonal variables did not show statistically significant associations with bone density at any site. Introduction FSH has been associated with bone density loss in animal models and longitudinal studies of women. Most of these analyses have not considered the effect of weight or race. Methods We tested the association between FSH and bone density in younger postmenopausal women, adjusting for patient-related factors. In 111 postmenopausal women aged 50–64 years, areal bone mineral density (BMD) was measured at the lumbar spine, femoral neck, total hip, and distal radius using dual-energy X-ray absorptiometry, and volumetric BMD was measured at the distal radius using peripheral quantitative computed tomography (pQCT). Height, weight, osteoporosis risk factors, and serum hormonal factors were assessed. Results FSH inversely correlated with weight, bioavailable estradiol, areal BMD at the lumbar spine and hip, and volumetric BMD at the ultradistal radius. In the multivariable analysis, no hormonal variable showed a statistically significant association with areal BMD at any site. Weight was independently associated with BMD at all central sites (p<0.001), but not with BMD or pQCT measures at the distal radius. Race was independently associated with areal BMD at all sites (p≤0.008) and with cortical area at the 33% distal radius (p=0.004). Conclusions Correlations between FSH and bioavailable estradiol and BMD did not persist after adjustment for weight and race in younger postmenopausal women. Weight and race were more important determinants of bone density and should be included in analyses of hormonal influences on bone. PMID:21125395

  8. Dynamic GSCA (Generalized Structured Component Analysis) with Applications to the Analysis of Effective Connectivity in Functional Neuroimaging Data

    ERIC Educational Resources Information Center

    Jung, Kwanghee; Takane, Yoshio; Hwang, Heungsun; Woodward, Todd S.

    2012-01-01

    We propose a new method of structural equation modeling (SEM) for longitudinal and time series data, named Dynamic GSCA (Generalized Structured Component Analysis). The proposed method extends the original GSCA by incorporating a multivariate autoregressive model to account for the dynamic nature of data taken over time. Dynamic GSCA also…

  9. The Developmental Association between Eating Disorders Symptoms and Symptoms of Depression and Anxiety in Juvenile Twin Girls

    ERIC Educational Resources Information Center

    Silberg, Judy L.; Bulik, Cynthia M.

    2005-01-01

    Objective: We investigated the role of genetic and environmental factors in the developmental association among symptoms of eating disorders, depression, and anxiety syndromes in 8-13-year-old and 14-17-year-old twin girls. Methods: Multivariate genetic models were fitted to child-reported longitudinal symptom data gathered from clinical interview…

  10. Does Learning to Read Improve Intelligence? A Longitudinal Multivariate Analysis in Identical Twins from Age 7 to 16

    ERIC Educational Resources Information Center

    Ritchie, Stuart J.; Bates, Timothy C.; Plomin, Robert

    2015-01-01

    Evidence from twin studies points to substantial environmental influences on intelligence, but the specifics of this influence are unclear. This study examined one developmental process that potentially causes intelligence differences: learning to read. In 1,890 twin pairs tested at 7, 9, 10, 12, and 16 years, a cross-lagged…

  11. Discrepancies between School Grades and Test Scores at Individual and School Level: Effects of Gender and Family Background

    ERIC Educational Resources Information Center

    Lekholm, Alli Klapp; Cliffordson, Christina

    2008-01-01

    The purpose of the study was to use multivariate multilevel techniques to investigate whether it was possible to separate different dimensions in grades that relate to subject-matter achievement and to other factors. Data were derived from The Gothenburg Educational Longitudinal Database (GOLD), and the subjects were 99,070 ninth-grade students…

  12. The Role of Personal Attributes and Social Support Factors on Passive Behaviour in Classroom among Secondary School Students: A Prospective Study

    ERIC Educational Resources Information Center

    Murberg, Terje A.

    2010-01-01

    The present study prospectively explored the effects of personal attributes (self-esteem and introversion) and social support factors on passive behaviour in the classroom in a sample of 259 (132 females, 127 males) students in two secondary schools. In the longitudinal multivariate analysis, the student's perceived passive behaviour in the…

  13. A novel statistical approach shows evidence for multi-system physiological dysregulation during aging.

    PubMed

    Cohen, Alan A; Milot, Emmanuel; Yong, Jian; Seplaki, Christopher L; Fülöp, Tamàs; Bandeen-Roche, Karen; Fried, Linda P

    2013-03-01

    Previous studies have identified many biomarkers that are associated with aging and related outcomes, but the relevance of these markers for underlying processes and their relationship to hypothesized systemic dysregulation is not clear. We address this gap by presenting a novel method for measuring dysregulation via the joint distribution of multiple biomarkers and assessing associations of dysregulation with age and mortality. Using longitudinal data from the Women's Health and Aging Study, we selected a 14-marker subset from 63 blood measures: those that diverged from the baseline population mean with age. For the 14 markers and all combinatorial sub-subsets we calculated a multivariate distance called the Mahalanobis distance (MHBD) for all observations, indicating how "strange" each individual's biomarker profile was relative to the baseline population mean. In most models, MHBD correlated positively with age, MHBD increased within individuals over time, and higher MHBD predicted higher risk of subsequent mortality. Predictive power increased as more variables were incorporated into the calculation of MHBD. Biomarkers from multiple systems were implicated. These results support hypotheses of simultaneous dysregulation in multiple systems and confirm the need for longitudinal, multivariate approaches to understanding biomarkers in aging. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  14. Longitudinal Consistency in Self-Reported Age of First Vaginal Intercourse Among Young Adults

    PubMed Central

    Goldberg, Shoshana K.; Haydon, Abigail A.; Herring, Amy H.; Halpern, Carolyn T.

    2014-01-01

    We examined consistency in self-reports of age at first vaginal sex among 9,399 male and female respondents who participated in Waves III and IV (separated by approximately 7 years) of the National Longitudinal Study of Adolescent Health (Add Health). Respondents were coded as consistent if they reported an age at first vaginal intercourse at Wave IV that was within 1 year of the age they reported at Wave III. Sociodemographic, behavioral, and cognitive predictors of consistency were examined using bivariate and multivariate logistic regression. Overall, 85.43% of respondents were able to provide consistent reports. Among both males and females, consistency was associated with age, years since first vaginal intercourse, race/ethnicity, and lifetime number of other-sex partners in final multivariate models. Respondents who were older and had more recently had their first sexual experience were more likely to be consistent. For females only, those who reported a history of non-parental, physically forced sex were less likely to be consistent. Most young adults consistently report age at first vaginal intercourse, supporting the credibility of retrospective self-reports about salient sexual events such as timing of first vaginal intercourse. PMID:23237101

  15. Patterns and Predictors of Language and Literacy Abilities 4-10 Years in the Longitudinal Study of Australian Children.

    PubMed

    Zubrick, Stephen R; Taylor, Catherine L; Christensen, Daniel

    2015-01-01

    Oral language is the foundation of literacy. Naturally, policies and practices to promote children's literacy begin in early childhood and have a strong focus on developing children's oral language, especially for children with known risk factors for low language ability. The underlying assumption is that children's progress along the oral to literate continuum is stable and predictable, such that low language ability foretells low literacy ability. This study investigated patterns and predictors of children's oral language and literacy abilities at 4, 6, 8 and 10 years. The study sample comprised 2,316 to 2,792 children from the first nationally representative Longitudinal Study of Australian Children (LSAC). Six developmental patterns were observed, a stable middle-high pattern, a stable low pattern, an improving pattern, a declining pattern, a fluctuating low pattern, and a fluctuating middle-high pattern. Most children (69%) fit a stable middle-high pattern. By contrast, less than 1% of children fit a stable low pattern. These results challenged the view that children's progress along the oral to literate continuum is stable and predictable. Multivariate logistic regression was used to investigate risks for low literacy ability at 10 years and sensitivity-specificity analysis was used to examine the predictive utility of the multivariate model. Predictors were modelled as risk variables with the lowest level of risk as the reference category. In the multivariate model, substantial risks for low literacy ability at 10 years, in order of descending magnitude, were: low school readiness, Aboriginal and/or Torres Strait Islander status and low language ability at 8 years. Moderate risks were high temperamental reactivity, low language ability at 4 years, and low language ability at 6 years. The following risk factors were not statistically significant in the multivariate model: Low maternal consistency, low family income, health care card, child not read to at home, maternal smoking, maternal education, family structure, temperamental persistence, and socio-economic area disadvantage. The results of the sensitivity-specificity analysis showed that a well-fitted multivariate model featuring risks of substantive magnitude did not do particularly well in predicting low literacy ability at 10 years.

  16. Longitudinal data analyses using linear mixed models in SPSS: concepts, procedures and illustrations.

    PubMed

    Shek, Daniel T L; Ma, Cecilia M S

    2011-01-05

    Although different methods are available for the analyses of longitudinal data, analyses based on generalized linear models (GLM) are criticized as violating the assumption of independence of observations. Alternatively, linear mixed models (LMM) are commonly used to understand changes in human behavior over time. In this paper, the basic concepts surrounding LMM (or hierarchical linear models) are outlined. Although SPSS is a statistical analyses package commonly used by researchers, documentation on LMM procedures in SPSS is not thorough or user friendly. With reference to this limitation, the related procedures for performing analyses based on LMM in SPSS are described. To demonstrate the application of LMM analyses in SPSS, findings based on six waves of data collected in the Project P.A.T.H.S. (Positive Adolescent Training through Holistic Social Programmes) in Hong Kong are presented.

  17. Longitudinal Data Analyses Using Linear Mixed Models in SPSS: Concepts, Procedures and Illustrations

    PubMed Central

    Shek, Daniel T. L.; Ma, Cecilia M. S.

    2011-01-01

    Although different methods are available for the analyses of longitudinal data, analyses based on generalized linear models (GLM) are criticized as violating the assumption of independence of observations. Alternatively, linear mixed models (LMM) are commonly used to understand changes in human behavior over time. In this paper, the basic concepts surrounding LMM (or hierarchical linear models) are outlined. Although SPSS is a statistical analyses package commonly used by researchers, documentation on LMM procedures in SPSS is not thorough or user friendly. With reference to this limitation, the related procedures for performing analyses based on LMM in SPSS are described. To demonstrate the application of LMM analyses in SPSS, findings based on six waves of data collected in the Project P.A.T.H.S. (Positive Adolescent Training through Holistic Social Programmes) in Hong Kong are presented. PMID:21218263

  18. "Old Age and Loneliness: Cross-Sectional and Longitudinal Analyses in the Tampere Longitudinal Study on Aging"

    ERIC Educational Resources Information Center

    Jylha, Marja

    2004-01-01

    The purpose of this study was to examine whether older age is associated with increasing loneliness in people aged 60 and over. Data came from TamELSA, a population-based prospective longitudinal study in Tampere, Finland. The followup time was 20 years. Loneliness was measured by a single question--"Do you feel lonely?"--with the…

  19. MULTIVARIATE ANALYSES (CONONICAL CORRELATION AND PARTIAL LEAST SQUARE, PLS) TO MODEL AND ASSESS THE ASSOCIATION OF LANDSCAPE METRICS TO SURFACE WATER CHEMICAL AND BIOLOGICAL PROPERTIES USING SAVANNAH RIVER BASIN DATA.

    EPA Science Inventory

    Many multivariate methods are used in describing and predicting relation; each has its unique usage of categorical and non-categorical data. In multivariate analysis of variance (MANOVA), many response variables (y's) are related to many independent variables that are categorical...

  20. Victimization Mediates the Longitudinal Association Between Depressive Symptoms and Violent Behaviors in Adolescence.

    PubMed

    Yu, Rongqin; Branje, Susan; Meeus, Wim; Koot, Hans M; van Lier, Pol; Fazel, Seena

    2018-05-01

    Despite evidence of a positive link between depressive symptoms and violent behaviors, the pathways underlying this longitudinal association remain unknown. Depressive symptoms might drive and reinforce victimization which in turn could increase risk of individuals becoming violent towards others. Thus, we tested whether victimization mediated the link between depressive symptoms and violent behaviors using a 6-year longitudinal study of a community sample of adolescents. The sample included 682 Dutch adolescents (54% boys) from an ongoing longitudinal study RADAR (Research on Adolescent Development and Relationships). From ages 13 to 18 years, depressive symptoms, victimization experiences, and violent behaviors were annually assessed. We conducted longitudinal mediation analyses to test pathways to violence in adolescents with depressive symptoms. Longitudinal analyses revealed that victimization mediated the association between depressive symptoms and violent behaviors from early to late adolescence. As part of this, we found that adolescents' depressive symptoms predicted victimization, and this victimization increased risk of subsequent violent behaviors. In conclusion, links between depressive symptoms and violent behaviors are potentially important to understand adolescent development. Decreasing the occurence of victimization is likely to be an important target for the prevention of violent behaviors in adolescents with depressive symptoms.

  1. Poverty, Depression, or Lost in Translation? Ethnic and Language Variation in Patient-Reported Outcomes in Rheumatoid Arthritis.

    PubMed

    Katz, Patricia P; Barton, Jennifer; Trupin, Laura; Schmajuk, Gabriela; Yazdany, Jinoos; Ruiz, Pedro J; Yelin, Edward

    2016-05-01

    Despite advances in therapies, disparities in outcomes have been documented for rheumatoid arthritis (RA) patients for both ethnicity and English language proficiency. The goals of these analyses were to compare differences in RA patient-reported outcomes, by both self-identification of ethnicity and English language proficiency, and to identify factors that might explain differences among groups. Data were collected through structured telephone interviews of a longitudinal cohort with physician-diagnosed RA (n = 438); only women were included (n = 335). Three groups were defined based on self-reported ethnicity and English proficiency: white/English (n = 219), Hispanic/English (n = 39), and Hispanic/Spanish (n = 77). Outcomes examined were patient-reported physical functioning, pain, and presence of moderate or severe fatigue. Multivariate regression analyses compared outcomes among groups, adjusting for sociodemographic characteristics, health and disease factors, and depression. Hispanic/Spanish women had worse function, pain, and fatigue than either English-proficient group. Depression was associated with all outcomes (P < 0.0001), and accounted for greater differentials in scores than ethnicity/language proficiency. In interaction analyses, differences between women who were and were not depressed were greater for Hispanic/English than for Hispanic/Spanish. Nondepressed Hispanic/Spanish scores were significantly worse than nondepressed Hispanic/English, i.e., the impact of depression was less for Hispanic/Spanish women because both depressed and nondepressed women in this group reported worse outcomes. After adjustment for sociodemographic factors and depression, language remained significantly associated with outcomes. Disparities in patient-reported outcomes may be driven less by ethnicity than by sociodemographic or psychological factors. Measurement instruments that are not culturally appropriate and equivalent may also hamper meaningful analyses of disparities. © 2016, American College of Rheumatology.

  2. Mediators of the relation between war experiences and suicidal ideation among former child soldiers in Northern Uganda: the WAYS study.

    PubMed

    Amone-P'Olak, Kennedy; Lekhutlile, Tlholego Molemane; Meiser-Stedman, Richard; Ovuga, Emilio

    2014-09-24

    Globally, suicide is a public health burden especially in the aftermath of war. Understanding the processes that define the path from previous war experiences (WE) to current suicidal ideation (SI) is crucial for defining opportunities for interventions. We assessed the extent to which different types of previous WE predict current SI and whether post-war hardships and depression mediate the relations between WE and SI among former child soldiers (FCS) in Northern Uganda. We performed cross-sectional analyses with a sample of 539 FCS (61% male) participating in an on-going longitudinal study. The influence of various types of previous WE on current SI and mediation by post-war hardships and depression were assessed by regression analyses. The following types of war experiences: "witnessing violence", "direct personal harm", "deaths", "Involvement in hostilities", "sexual abuse" and "general war experiences" significantly predicted current SI in a univariable analyses whereas "direct personal harm", "involvement in hostilities", and "sexual abuse" independently predicted current SI in a multivariable analyses. General WE were linked to SI (β = 0.18 (95% CI 0.10 to 0.25)) through post-war hardships (accounting for 69% of the variance in their relationship) and through depression/anxiety (β = 0.17 (95% CI 0.12 to 0.22)) accounting for 65% of the variance in their relationship. The direct relationship between previous WE and current SI reduced but remained marginally significant (β = .08, CI: (.01, .17) for depression/anxiety but not for post-war hardships (β = .09, CI: (-.03, .20). Types of WE should be examined when assessing risks for SI. Interventions to reduce SI should aim to alleviate post-war hardships and treat depression/anxiety.

  3. Socio-economic marginalization and plasma HIV-1 RNA non-detectability among individuals who use illicit drugs in a Canadian setting

    PubMed Central

    RICHARDSON, Lindsey A.; KERR, Thomas H.; DOBRER, Sabina; PUSKAS, Cathy M.; GUILLEMI, Silvia A.; MONTANER, Julio S. G.; WOOD, Evan; MILLOY, M-J. S.

    2015-01-01

    Objective Given that people who use illicit drugs (PWUD) often engage in prohibited income generation to support their basic needs, we sought to examine the role of these activities in shaping antiretroviral therapy (ART) adherence and plasma HIV RNA-1 viral load suppression among HIV-infected PWUD. Design Longitudinal analyses among HIV-positive, ART exposed PWUD in the AIDS Care Cohort to evaluate Exposure to Survival Services prospective cohort study (2005–2013). Methods Generalized linear mixed effects and mediation analyses examined the relationship between prohibited income generation (e.g. sex work, drug dealing, theft, street-based income) and virologic suppression (plasma viral load ≤ 50 copies/mL plasma) adjusting for adherence and potential confounders. Results Among 687 HIV-infected PWUD, 391 (56.9%) individuals reported prohibited income generation activity during the study period. In multivariate analyses, prohibited income generation remained independently and negatively associated with virologic suppression (adjusted odds ratio: 0.68, 95% confidence interval: 0.52–0.88) following adjustment for hypothesized confounders, including high-intensity drug use, ART adherence and homelessness. While partially mediated by ART adherence, the relationship between prohibited income generation and virologic suppression was maintained in mediation analyses (Sobel statistic = −1.95, p=0.05). Conclusions Involvement in prohibited income generation decreases the likelihood of virologic suppression directly and indirectly through its negative association with ART adherence. These findings suggest that linkages between socio-economic marginalization, the criminalization of illicit drug use and insufficient employment opportunities may produce barriers to access and retention in care. Programmatic and policy interventions that decrease socio-economic vulnerability may therefore reduce HIV-related morbidity, mortality and onward transmission. PMID:26558546

  4. Does psychedelic drug use reduce risk of suicidality? Evidence from a longitudinal community-based cohort of marginalised women in a Canadian setting

    PubMed Central

    Argento, Elena; Strathdee, Steffanie A; Tupper, Kenneth; Braschel, Melissa; Wood, Evan; Shannon, Kate

    2017-01-01

    Objective This study aimed to longitudinally investigate whether ever having used a psychedelic drug can have a protective effect on incidence of suicidality among marginalised women. Design Longitudinal community-based cohort study. Setting Data were drawn from a prospective, community-based cohort of marginalised women in Metro Vancouver, Canada. Participants 766 women completed the baseline questionnaire between January 2010 and August 2014. Participants who did not report suicidality at baseline and who completed at least one follow-up visit were included. Main outcome measure Extended Cox regression was used to model predictors of new suicidality (suicide ideation or attempts) over 54-month follow-up. Results Nearly half (46%; n=355) of participants reported prior suicidality and were thus excluded from the present analyses. Of 290 women eligible at baseline, 11% (n=31) reported recent suicidality during follow-up, with an incidence density of 4.42 per 100 person-years (95% CI 3.10 to 6.30). In multivariable analysis, reported lifetime psychedelic drug use was associated with a 60% reduced hazard for suicidality (adjusted HR (AHR) 0.40; 95% CI 0.17 to 0.94). Crystal methamphetamine use (AHR 3.25; 95% CI 1.47 to 7.21) and childhood abuse (AHR 3.54; 95% CI 1.49 to 8.40) remained independent predictors of suicidality. Conclusion The high rate of suicidality identified in this study is of major concern. Alongside emerging evidence on the potential of psychedelic-assisted therapy to treat some mental illness and addiction issues, our findings demonstrate that naturalistic psychedelic drug use is independently associated with reduced suicidality, while other illicit drug use and childhood trauma predispose women to suicidality. While observational, this study supports calls for further investigation of the therapeutic utility of psychedelic drugs in treating poor mental health and promoting mental wellness. PMID:28939573

  5. Left ventricular myocardial velocities and deformation indexes in top-level athletes.

    PubMed

    D'Andrea, Antonello; Cocchia, Rosangela; Riegler, Lucia; Scarafile, Raffaella; Salerno, Gemma; Gravino, Rita; Golia, Enrica; Pezzullo, Enrica; Citro, Rodolfo; Limongelli, Giuseppe; Pacileo, Giuseppe; Cuomo, Sergio; Caso, Pio; Russo, Maria Giovanna; Bossone, Eduardo; Calabrò, Raffaele

    2010-12-01

    The aim of this study was to define the range of left ventricular (LV) velocities and deformation indexes in highly trained athletes, analyzing potential differences induced by different long-term training protocols. Standard echocardiography, pulsed-wave tissue Doppler echocardiography, and two-dimensional strain echocardiography of the interventricular septum and lateral wall were performed in 370 endurance athletes and 280 power athletes. Using pulsed-wave tissue Doppler, the following parameters of myocardial function were assessed: systolic peak velocities (S(m)), early (E(m)) and late (A(m)) diastolic velocities, and the E(m)/A(m) ratio. By two-dimensional strain echocardiography, peaks of regional systolic strain and LV global longitudinal strain were calculated. LV mass index and ejection fraction did not significantly differ between the two groups. However, power athletes showed an increased sum of wall thicknesses (P < .01) and relative wall thickness, while LV stroke volume and LV end-diastolic diameter (P < .001) were greater in endurance athletes. By pulsed-wave tissue Doppler analysis, E(m) and E(m)/A(m) at both the septal and lateral wall levels were higher in endurance athletes. By two-dimensional strain echocardiography, myocardial deformation indexes were comparable between the two groups. E(m)/A(m) ratios ≥ 1 were found in the overall population, while 90 % of athletes had an E(m) ≥ 16 cm/sec, S(m) ≥ 10 cm/sec, and global longitudinal strain ≤ -16%. Multivariate analyses evidenced independent positive association between Em peak velocity and LV end-diastolic volume (P < .001) and an independent correlation of global longitudinal strain with the sum of LV wall thicknesses (P < .005). This study describes the full spectrum of systolic and diastolic myocardial velocities and deformation indexes in a large population of competitive athletes. Copyright © 2010 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.

  6. Individual and social determinants of multiple chronic disease behavioral risk factors among youth.

    PubMed

    Alamian, Arsham; Paradis, Gilles

    2012-03-22

    Behavioral risk factors are known to co-occur among youth, and to increase risks of chronic diseases morbidity and mortality later in life. However, little is known about determinants of multiple chronic disease behavioral risk factors, particularly among youth. Previous studies have been cross-sectional and carried out without a sound theoretical framework. Using longitudinal data (n = 1135) from Cycle 4 (2000-2001), Cycle 5 (2002-2003) and Cycle 6 (2004-2005) of the National Longitudinal Survey of Children and Youth, a nationally representative sample of Canadian children who are followed biennially, the present study examines the influence of a set of conceptually-related individual/social distal variables (variables situated at an intermediate distance from behaviors), and individual/social ultimate variables (variables situated at an utmost distance from behaviors) on the rate of occurrence of multiple behavioral risk factors (physical inactivity, sedentary behavior, tobacco smoking, alcohol drinking, and high body mass index) in a sample of children aged 10-11 years at baseline. Multiple behavioral risk factors were assessed using a multiple risk factor score. All statistical analyses were performed using SAS, version 9.1, and SUDAAN, version 9.01. Multivariate longitudinal Poisson models showed that social distal variables including parental/peer smoking and peer drinking (Log-likelihood ratio (LLR) = 187.86, degrees of freedom (DF) = 8, p < .001), as well as individual distal variables including low self-esteem (LLR = 76.94, DF = 4, p < .001) increased the rate of occurrence of multiple behavioral risk factors. Individual ultimate variables including age, sex, and anxiety (LLR = 9.34, DF = 3, p < .05), as well as social ultimate variables including family socioeconomic status, and family structure (LLR = 10.93, DF = 5, p = .05) contributed minimally to the rate of co-occurrence of behavioral risk factors. The results suggest targeting individual/social distal variables in prevention programs of multiple chronic disease behavioral risk factors among youth.

  7. Parental History of Premature Cardiovascular Disease, Estimated GFR, and Rate of Estimated GFR Decline: Results From the Aerobics Center Longitudinal Study

    PubMed Central

    Huang, Xiaoyan; Sui, Xuemei; Ruiz, Jonatan R.; Hirth, Victor; Ortega, Francisco B.; Blair, Steven N.; Carrero, Juan J.

    2015-01-01

    Background Despite cardiovascular disease (CVD) and chronic kidney disease (CKD) sharing similar etiologies and interplay, it remains unknown if a broader relationship between these diseases exists across generations. We investigated the association between parental CVD history and estimated glomerular filtration rate (eGFR) in the community. Study Design Cross-sectional and longitudinal analyses. Setting & Participants A total of 13,241 community-based adults with serum creatinine measurement and follow-up visits (from 1 to 8 visits, approximately 2 years apart) from the Aerobics Center Longitudinal Study. Predictors Premature parental CVD history (before age of 50 years). Outcomes eGFR, decreased eGFR (<60 mL/min/1.73m2), and rate of eGFR decline. Measurements Information of parental history was collected by protocol-standardized questionnaires. eGFR was assessed with serum creatinine. Results A total of 3,339 (25.2%) participants reported a history of parental CVD. Individuals with parental CVD had significantly lower eGFR compared with those without parental CVD (69.4 ± 12.9 vs. 74.8 ± 14.2 mL/min/1.73m2; P<0.001). After multivariable adjustment, parental CVD was independently associated with higher odds of having decreased eGFR (adjusted OR, 1.68; 95% CI, 1.52–1.86). Random-coefficient models showed that individuals with parental CVD had a faster decline in eGFR compared with those without parental CVD (sex- and ethnicity-adjusted annual change of −0.47 vs. −0.41 mL/min/1.73 m2; P=0.06). Limitations Approximately 70% of the participants did not attend a second examination. Conclusions Parental history of CVD was associated with lower baseline eGFR, higher odds of decreased eGFR, and a nominally faster rate of eGFR decline in the offspring. Such findings may imply previously unrecognized cross-generational links between both diseases and be of support in community screening programs. PMID:25600488

  8. Nitrates in drinking water and methemoglobin levels in pregnancy: a longitudinal study.

    PubMed

    Manassaram, Deana M; Backer, Lorraine C; Messing, Rita; Fleming, Lora E; Luke, Barbara; Monteilh, Carolyn P

    2010-10-14

    Private water systems are more likely to have nitrate levels above the maximum contaminant level (MCL). Pregnant women are considered vulnerable to the effects of exposure to high levels of nitrates in drinking water due to their altered physiological states. The level of methemoglobin in the blood is the biomarker often used in research for assessing exposure to nitrates. The objective of this study was to assess methemoglobin levels and examine how various factors affected methemoglobin levels during pregnancy. We also examined whether differences in water use practices existed among pregnant women based on household drinking water source of private vs. public supply. A longitudinal study of 357 pregnant women was conducted. Longitudinal regression models were used to examine changes and predictors of the change in methemoglobin levels over the period of gestation. Pregnant women showed a decrease in methemoglobin levels with increasing gestation although <1% had levels above the physiologic normal of 2% methemoglobin, regardless of the source of their drinking water. The multivariable analyses did not show a statistically significant association between methemoglobin levels and the estimated nitrate intake from tap water among pregnant women around 36 weeks gestation (β = 0.046, p = 0.986). Four women had tap water nitrate levels above the MCL of 10 mg/L. At enrollment, a greater proportion of women who reported using water treatment devices were private wells users (66%) compared to public system users (46%) (p < 0.0001). Also, a greater proportion of private well users (27%) compared to public system users (13%) were using devices capable of removing nitrate from water (p < 0.0001). Pregnant women potentially exposed to nitrate levels primarily below the MCL for drinking water were unlikely to show methemoglobin levels above the physiologic normal. Water use practices such as the use of treatment devices to remove nitrates varied according to water source and should be considered in the assessment of exposure to nitrates in future studies.

  9. Nitrates in drinking water and methemoglobin levels in pregnancy: a longitudinal study

    PubMed Central

    2010-01-01

    Background Private water systems are more likely to have nitrate levels above the maximum contaminant level (MCL). Pregnant women are considered vulnerable to the effects of exposure to high levels of nitrates in drinking water due to their altered physiological states. The level of methemoglobin in the blood is the biomarker often used in research for assessing exposure to nitrates. The objective of this study was to assess methemoglobin levels and examine how various factors affected methemoglobin levels during pregnancy. We also examined whether differences in water use practices existed among pregnant women based on household drinking water source of private vs. public supply. Methods A longitudinal study of 357 pregnant women was conducted. Longitudinal regression models were used to examine changes and predictors of the change in methemoglobin levels over the period of gestation. Results Pregnant women showed a decrease in methemoglobin levels with increasing gestation although <1% had levels above the physiologic normal of 2% methemoglobin, regardless of the source of their drinking water. The multivariable analyses did not show a statistically significant association between methemoglobin levels and the estimated nitrate intake from tap water among pregnant women around 36 weeks gestation (β = 0.046, p = 0.986). Four women had tap water nitrate levels above the MCL of 10 mg/L. At enrollment, a greater proportion of women who reported using water treatment devices were private wells users (66%) compared to public system users (46%) (p < 0.0001). Also, a greater proportion of private well users (27%) compared to public system users (13%) were using devices capable of removing nitrate from water (p < 0.0001). Conclusion Pregnant women potentially exposed to nitrate levels primarily below the MCL for drinking water were unlikely to show methemoglobin levels above the physiologic normal. Water use practices such as the use of treatment devices to remove nitrates varied according to water source and should be considered in the assessment of exposure to nitrates in future studies. PMID:20946657

  10. Semiparametric Estimation of the Impacts of Longitudinal Interventions on Adolescent Obesity using Targeted Maximum-Likelihood: Accessible Estimation with the ltmle Package

    PubMed Central

    Decker, Anna L.; Hubbard, Alan; Crespi, Catherine M.; Seto, Edmund Y.W.; Wang, May C.

    2015-01-01

    While child and adolescent obesity is a serious public health concern, few studies have utilized parameters based on the causal inference literature to examine the potential impacts of early intervention. The purpose of this analysis was to estimate the causal effects of early interventions to improve physical activity and diet during adolescence on body mass index (BMI), a measure of adiposity, using improved techniques. The most widespread statistical method in studies of child and adolescent obesity is multi-variable regression, with the parameter of interest being the coefficient on the variable of interest. This approach does not appropriately adjust for time-dependent confounding, and the modeling assumptions may not always be met. An alternative parameter to estimate is one motivated by the causal inference literature, which can be interpreted as the mean change in the outcome under interventions to set the exposure of interest. The underlying data-generating distribution, upon which the estimator is based, can be estimated via a parametric or semi-parametric approach. Using data from the National Heart, Lung, and Blood Institute Growth and Health Study, a 10-year prospective cohort study of adolescent girls, we estimated the longitudinal impact of physical activity and diet interventions on 10-year BMI z-scores via a parameter motivated by the causal inference literature, using both parametric and semi-parametric estimation approaches. The parameters of interest were estimated with a recently released R package, ltmle, for estimating means based upon general longitudinal treatment regimes. We found that early, sustained intervention on total calories had a greater impact than a physical activity intervention or non-sustained interventions. Multivariable linear regression yielded inflated effect estimates compared to estimates based on targeted maximum-likelihood estimation and data-adaptive super learning. Our analysis demonstrates that sophisticated, optimal semiparametric estimation of longitudinal treatment-specific means via ltmle provides an incredibly powerful, yet easy-to-use tool, removing impediments for putting theory into practice. PMID:26046009

  11. The influence of unmet supportive care needs on anxiety and depression during cancer treatment and beyond: a longitudinal study of survivors of haematological cancers.

    PubMed

    Oberoi, Devesh; White, Victoria M; Seymour, John F; Miles Prince, H; Harrison, Simon; Jefford, Michael; Winship, Ingrid; Hill, David; Bolton, Damien; Kay, Anne; Millar, Jeremy; Doo, Nicole Wong; Giles, Graham

    2017-11-01

    This paper aims to examine the cross-sectional and longitudinal associations between patient-reported unmet needs and anxiety and depression for survivors of diffuse large B cell lymphoma (DLBCL) and multiple myeloma (MM). In a longitudinal study design, self-reported data were collected through telephone interviews at two time points approximately 7 (T1) and 15 (T2) months post-diagnosis. The sample was recruited through the population-based Victorian Cancer Registry. At T1 and T2, the study outcomes, anxiety and depression, were assessed using the Hospital Anxiety and Depression Scale (HADS) and unmet needs were measured using the Supportive Care Needs Survey (SCNS-SF34). Questions related to social/family problems, relationship problems and financial problems were also asked. A three-step multivariable hierarchical logistic regression analysis examined the relative role of T1 anxiety and depression, T1 and T2 unmet needs and other psychosocial factors with T2 anxiety and depression. Both cross-sectional and longitudinal associations were observed between unmet needs and psychological distress. T2 anxiety was associated with T1 anxiety (OR 4.75, 95% CI 1.86-11.09), T2 psychological needs (OR 1.68, 95% CI 1.34-2.11) and with T1 social problems (OR 2.33, 95% CI 1.03-5.05) in multivariate analysis. T2 depression was associated with both T1 (OR 1.28, 95% CI 1.06-1.57) and T2 psychological needs (OR 1.35, 95% CI 1.06-1.70), T2 physical needs (OR 1.89, 95% CI 1.27-2.81) and T1 depression (OR 4.52, 95% CI 1.88-10.86). Unmet needs that manifest following diagnosis and treatment may persist into early survivorship and contribute to psychological distress. Addressing these needs during treatment may diminish the risk of current and future anxiety and depression.

  12. MGAS: a powerful tool for multivariate gene-based genome-wide association analysis.

    PubMed

    Van der Sluis, Sophie; Dolan, Conor V; Li, Jiang; Song, Youqiang; Sham, Pak; Posthuma, Danielle; Li, Miao-Xin

    2015-04-01

    Standard genome-wide association studies, testing the association between one phenotype and a large number of single nucleotide polymorphisms (SNPs), are limited in two ways: (i) traits are often multivariate, and analysis of composite scores entails loss in statistical power and (ii) gene-based analyses may be preferred, e.g. to decrease the multiple testing problem. Here we present a new method, multivariate gene-based association test by extended Simes procedure (MGAS), that allows gene-based testing of multivariate phenotypes in unrelated individuals. Through extensive simulation, we show that under most trait-generating genotype-phenotype models MGAS has superior statistical power to detect associated genes compared with gene-based analyses of univariate phenotypic composite scores (i.e. GATES, multiple regression), and multivariate analysis of variance (MANOVA). Re-analysis of metabolic data revealed 32 False Discovery Rate controlled genome-wide significant genes, and 12 regions harboring multiple genes; of these 44 regions, 30 were not reported in the original analysis. MGAS allows researchers to conduct their multivariate gene-based analyses efficiently, and without the loss of power that is often associated with an incorrectly specified genotype-phenotype models. MGAS is freely available in KGG v3.0 (http://statgenpro.psychiatry.hku.hk/limx/kgg/download.php). Access to the metabolic dataset can be requested at dbGaP (https://dbgap.ncbi.nlm.nih.gov/). The R-simulation code is available from http://ctglab.nl/people/sophie_van_der_sluis. Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press.

  13. Comparison of efficiency of distance measurement methodologies in mango (Mangifera indica) progenies based on physicochemical descriptors.

    PubMed

    Alves, E O S; Cerqueira-Silva, C B M; Souza, A M; Santos, C A F; Lima Neto, F P; Corrêa, R X

    2012-03-14

    We investigated seven distance measures in a set of observations of physicochemical variables of mango (Mangifera indica) submitted to multivariate analyses (distance, projection and grouping). To estimate the distance measurements, five mango progeny (total of 25 genotypes) were analyzed, using six fruit physicochemical descriptors (fruit weight, equatorial diameter, longitudinal diameter, total soluble solids in °Brix, total titratable acidity, and pH). The distance measurements were compared by the Spearman correlation test, projection in two-dimensional space and grouping efficiency. The Spearman correlation coefficients between the seven distance measurements were, except for the Mahalanobis' generalized distance (0.41 ≤ rs ≤ 0.63), high and significant (rs ≥ 0.91; P < 0.001). Regardless of the origin of the distance matrix, the unweighted pair group method with arithmetic mean grouping method proved to be the most adequate. The various distance measurements and grouping methods gave different values for distortion (-116.5 ≤ D ≤ 74.5), cophenetic correlation (0.26 ≤ rc ≤ 0.76) and stress (-1.9 ≤ S ≤ 58.9). Choice of distance measurement and analysis methods influence the.

  14. The Multivariate Roles of Family Instability and Interparental Conflict in Predicting Children’s Representations of Insecurity in the Family System and Early School Adjustment Problems

    PubMed Central

    Coe, Jesse L.; Davies, Patrick T.; Sturge-Apple, Melissa L.

    2016-01-01

    This study examined the moderating role of family instability in relations involving destructive interparental conflict, children’s internal representations of insecurity in the family system, and their early school maladjustment. Two hundred forty-three preschool children (M age = 4.60 years; 56% girls) and their families participated in this multi-method (i.e., observations, structured interview, surveys) multi-informant (i.e., observer, parent, teacher), longitudinal study. Findings indicated that the mediational role of children’s insecure family representations in the pathway between destructive interparental conflict and children’s adjustment problems varied significantly depending on the level of family instability. Interparental conflict was specifically associated with insecure family representations only under conditions of low family instability. In supporting the role of family instability as a vulnerable-stable risk factor, follow up analyses revealed that children’s concerns about security in the family were uniformly high under conditions of heightened instability regardless of their level of exposure to interparental conflict. PMID:27146062

  15. Autonomous motivation is associated with the maintenance stage of behaviour change in people with affective disorders.

    PubMed

    Vancampfort, Davy; Moens, Herman; Madou, Tomas; De Backer, Tanja; Vallons, Veerle; Bruyninx, Peter; Vanheuverzwijn, Sarah; Mota, Cindy Teixeira; Soundy, Andy; Probst, Michel

    2016-06-30

    The present study examined whether in people with affective disorders motives for adopting and maintaining physical activity recommendations (as formulated by the self-determination theory) differed across the stages of behaviour change (identified by the transtheoretical model). A total of 165 (105♀) persons (45.6±14.2years) with affective disorders [major depressive disorder (n=96) or bipolar disorder (n=69)] completed the Behavioural Regulation in Exercise Questionnaire-2 and the Patient-centred Assessment and Counselling for Exercise questionnaire. Discriminant and multivariate analyses demonstrated that persons with affective disorders at the early stages of change have less autonomous and more controlled physical activity motives than those at the later stages. Our results suggest that autonomous motivation may have an important role to play in the maintenance of health recommendations in persons with affective disorders. Longitudinal and intervention studies should be designed in people with affective disorders to identify the causal pathways between motives for maintaining health recommendations, effective changes in health behaviour and physical and mental health outcomes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Housing tenure as a focus for reducing inequalities in the home safety environment: evidence from Growing Up in New Zealand.

    PubMed

    Berry, Sarah; Carr, Polly Atatoa; Kool, Bridget; Mohal, Jatender; Morton, Susan; Grant, Cameron

    2017-10-01

    To determine whether specific demographic characteristics are associated with the presence or absence of household safety strategies. This study was conducted within Growing Up in New Zealand, a contemporary longitudinal study of New Zealand (NZ) children. Multivariable analyses were used to examine the maternal (self-prioritised ethnicity, education, age, self-reported health) and household (area-level deprivation, tenure, crowding, residential mobility, dwelling type) determinants of household safety strategies being present in the homes of young children. In comparison to family-owned homes, privately owned rental homes were less likely (OR=0.78; 95%CI 0.65-0.92), and government-owned rental homes were more likely (OR=1.74, 95%CI 1.25-2.41) to have eight or more household safety strategies present. Living in a privately owned rental home in NZ exposes children to an environment where there are fewer household safety strategies in place. Implications for public health: Housing tenure provides a clear target focus for improving the household safety environment for NZ children. © 2017 The Authors.

  17. Social relationships, loneliness, and mental health among older men and women in Ireland: A prospective community-based study.

    PubMed

    Santini, Ziggi Ivan; Fiori, Katherine Leigh; Feeney, Joanne; Tyrovolas, Stefanos; Haro, Josep Maria; Koyanagi, Ai

    2016-11-01

    Data is lacking on the association of interpersonal stressors and social isolation with mental disorders and the mediating role of loneliness. Thus, we examined this association prospectively using community-based data. Data on 6105 adults aged ≥50 years from the Irish Longitudinal Study on Ageing (TILDA) was analyzed. Mental health outcomes were assessed 2 years after baseline. Depressive and anxiety symptoms were evaluated with validated scales. Multivariable linear regression and mediation analyses were conducted. Higher levels of spousal support, less strain from spouse and better social network integration were protective against depressive symptoms in men. Social support from friends and children was protective against depressive symptoms in both genders. Higher levels of social strain from children were positively associated with depressive symptoms in women. Loneliness was a significant mediator in the majority of these associations. Interventions aimed at increasing relationship quality and strengthening existing social network structures, with a specific focus on reducing feelings of loneliness, may be beneficial in the prevention of depressive symptoms among older adults. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Non-linear relationship between maternal work hours and child body weight: Evidence from the Western Australian Pregnancy Cohort (Raine) Study.

    PubMed

    Li, Jianghong; Akaliyski, Plamen; Schäfer, Jakob; Kendall, Garth; Oddy, Wendy H; Stanley, Fiona; Strazdins, Lyndall

    2017-08-01

    Using longitudinal data from the Western Australia Pregnancy Cohort (Raine) Study and both random-effects and fixed-effects models, this study examined the connection between maternal work hours and child overweight or obesity. Following children in two-parent families from early childhood to early adolescence, multivariate analyses revealed a non-linear and developmentally dynamic relationship. Among preschool children (ages 2 to 5), we found lower likelihood of child overweight and obesity when mothers worked 24 h or less per week, compared to when mothers worked 35 or more hours. This effect was stronger in low-to-medium income families. For older children (ages 8 to 14), compared to working 35-40 h a week, working shorter hours (1-24, 25-34) or longer hours (41 or more) was both associated with increases in child overweight and obesity. These non-linear effects were more pronounced in low-to-medium income families, particularly when fathers also worked long hours. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Workplace changes associated with a reduction in musculoskeletal symptoms in office workers.

    PubMed

    Nelson, N A; Silverstein, B A

    1998-06-01

    The purpose of this study was to identify factors associated with reductions observed in musculoskeletal symptoms when office workers were moved to a new building. A questionnaire including items regarding symptoms and aspects of the work environment was administered to 577 office workers before and after they were moved from nine buildings to a single new facility in 1992. Employees working in two reference buildings, where they remained throughout the study period, were also surveyed. Two musculoskeletal outcomes, hand/arm and neck/shoulder/back, were selected for study. In matched multivariate analyses, the reduction in hand/arm symptoms from 1992 to 1993 was associated with improved satisfaction with the physical workstation (odds ratio [OR] = 2.0); the reduction in neck/shoulder/back symptoms was associated with improved chair comfort (OR = 1.8), fewer housekeeping responsibilities (OR = 3.6), female gender (OR = 1.8), and low pay range (OR = 1.7). Longitudinal results suggested that changes in workstations resulted in decreased symptoms. Results of this investigation might be used to develop workplace changes that result in reductions of musculoskeletal disorders.

  20. Use of Highly Active Antiretroviral Therapy in a Cohort of HIV-Seropositive Women

    PubMed Central

    Cook, Judith A.; Cohen, Mardge H.; Grey, Dennis; Kirstein, Lynn; Burke, Jane; Anastos, Kathryn; Palacio, Herminia; Richardson, Jean; Wilson, Tracey E.; Young, Mary

    2002-01-01

    Objectives. This study examined longitudinal trends in use of highly active antiretroviral therapy (HAART) among a cohort of HIV-positive participants in the Women's Interagency HIV Study. Methods. Beginning in 1994, 1690 HIV-positive women reported detailed information about their use of antiretroviral therapy at 6-month study visits. Multivariate logistic and Cox regression analyses were used to estimate the likelihood of antiretroviral therapy and HAART use among women with study visits preceding and following HAART availability. Results. Before the availability of HAART, the cohort's likelihood of any antiretroviral therapy use was associated with clinical indicators (CD4 count, viral load, symptom presence) as well as behavioral factors (abstaining from drug and alcohol use, participating in clinical trials). After HAART became commercially available, newly emerging predictors included college education, private insurance, absence of injection drug use history, and not being African American. Conclusions. After the penetration of HAART into this cohort, additional differences emerged between HAART users and nonusers. These findings can inform public health efforts to enhance women's access to the most effective types of therapy. PMID:11772767

  1. Physical and mental health disparities among young children of Asian immigrants.

    PubMed

    Huang, Keng-Yen; Calzada, Esther; Cheng, Sabrina; Brotman, Laurie Miller

    2012-02-01

    To examine physical and mental health functioning among Asian-American children of US-born and immigrant parents. We used data from the Early Childhood Longitudinal Study-Kindergarten Class of 1998-1999 base-year public data file. The sample was restricted to 7726 Asian and US-born white children. Asian subgroups were created based on parents' country of birth. Child physical and mental health was assessed based on multiple sources of data and measures. Analyses included multivariate linear and logistic regression. After adjusting for demographic and contextual differences, disparities were found for physical and mental health indicators. Children of foreign-born Asian families (from east, southeast, and south Asia) were at greater risk for poor physical health, internalizing problems, and inadequate interpersonal relationships compared with children of US-born white families. There is little support for the "model minority" myth with regard to physical and mental health. Evidence of physical and mental health disparities among young Asian-American children and differing risk based on region of origin of immigrant parents suggests the need for culturally informed prevention efforts during early childhood. Copyright © 2012 Mosby, Inc. All rights reserved.

  2. Wealth and Its Associations with Enteric Parasitic Infections in a Low-Income Community in Peru: Use of Principal Component Analysis

    PubMed Central

    Nundy, Shantanu; Gilman, Robert H.; Xiao, Lihua; Cabrera, Lilia; Cama, Rosa; Ortega, Ynes R.; Kahn, Geoffrey; Cama, Vitaliano A.

    2011-01-01

    The association of wealth and infections with Giardia, Cryptosporidium, Cyclospora, and microsporidia were examined in a longitudinal cohort conducted in Peru from 2001 to 2006. Data from 492 participants were daily clinical manifestations, weekly copro-parasitological diagnosis, and housing characteristics and assets owned (48 variables), and these data were used to construct a global wealth index using principal component analysis. Data were analyzed using continuous and categorical (wealth tertiles) models. Participant's mean age was 3.43 years (range = 0–12 years), with average follow-up of 993 days. Univariate and multivariate analyses identified significant associations between wealth and infections with Giardia and microsporidia. Participants with greater wealth indexes were associated with protection against Giardia (P < 0.001) and persistent Giardia infections (> 14 days). For microsporidia, greater wealth was protective (P = 0.066 continuous and P = 0.042 by tertiles). Contrarily, infections with Cryptosporidium and Cyclospora were independent of wealth. Thus, subtle differences in wealth may affect the frequency of specific parasitic infections within low-income communities. PMID:21212198

  3. Life resources and personal goals in old age.

    PubMed

    Saajanaho, Milla; Rantakokko, Merja; Portegijs, Erja; Törmäkangas, Timo; Eronen, Johanna; Tsai, Li-Tang; Jylhä, Marja; Rantanen, Taina

    2016-09-01

    It has been theorized that life resources influence goal engagement. The aim of the present study was to examine whether personal characteristics, and socio-economic, social and health resources are associated with personal goal content in old age. The participants were 824 community-dwelling people aged 75-90 from the Life-Space Mobility in Old Age project. Personal goals were elicited using a revised version of the Personal Project Analysis in a structured interview. Cross-sectional bi- and multivariate analyses using logistic regression modelling were conducted. The results showed that the most commonly reported goals were health maintenance related. People with better health resources were more likely to report goals related to leisure-time, social and physical activities and less likely to report goals related to recovery of health. Those with poor social resources were at risk for having no personal goals in their lives. The results are in line with theorizing on the influence of life resources on goal setting in old age. Further longitudinal studies are needed on whether resource loss precedes goal modification, and how goal setting strategies influence both mental and physical well-being in old age.

  4. Studies to determine the effectiveness of longitudinal channelizing devices in work zones.

    DOT National Transportation Integrated Search

    2011-01-01

    This report describes the methodology and results of analyses performed to determine whether the following longitudinal : channelizing device (LCD) applications improve the traffic safety and operations of work zones relative to the use of standard :...

  5. Disentangling the Effects of Violent Victimization, Violent Behavior, and Gun Carrying for Minority Inner-City Youth Living in Extreme Poverty

    ERIC Educational Resources Information Center

    Spano, Richard; Bolland, John

    2013-01-01

    Two waves of longitudinal data were used to examine the sequencing between violent victimization, violent behavior, and gun carrying in a high-poverty sample of African American youth. Multivariate logistic regression results indicated that violent victimization T1 and violent behavior T1 increased the likelihood of initiation of gun carrying T2…

  6. Assessing the Effectiveness of a School-Based Dental Clinic on the Oral Health of Children Who Lack Access to Dental Care: A Program Evaluation

    ERIC Educational Resources Information Center

    Carpino, Rachel; Walker, Mary P.; Liu, Ying; Simmer-Beck, Melanie

    2017-01-01

    This program evaluation examines the effectiveness of a school-based dental clinic. A repeated-measures design was used to longitudinally examine secondary data from participants (N = 293). Encounter intensity was developed to normalize data. Multivariate analysis of variance and Kruskal-Wallis test were used to investigate the effect of encounter…

  7. Causal diagrams and multivariate analysis II: precision work.

    PubMed

    Jupiter, Daniel C

    2014-01-01

    In this Investigators' Corner, I continue my discussion of when and why we researchers should include variables in multivariate regression. My examination focuses on studies comparing treatment groups and situations for which we can either exclude variables from multivariate analyses or include them for reasons of precision. Copyright © 2014 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  8. Eating disorders: predictors of change in the quality of life of caregivers.

    PubMed

    Las Hayas, Carlota; Padierna, Jesús Ángel; Bilbao, Amaia; Martín, Josune; Muñoz, Pedro; Quintana, Jose María

    2014-03-30

    Eating disorders (EDs) have a strong impact on the quality of life (QoL) of caregivers. This study explores the longitudinal changes in the QoL of ED caregivers at 1 (T1; n=109) and 2 years (T2; n=32) follow-up, and identifies predictors of improvement at 1-year follow-up. ED outpatients also completed a battery of tests at T1 (n=69) and T2 (n=11). Multivariate hierarchical linear mixed models were used, in which the caregivers' 1-year changes in QoL, anxiety and depression scores were analysed as the dependent variables. Predictor variables were the caregivers' perception of burden, perception of the severity of the patient's ED, kinship data, and the ED person's scores on QoL, anxiety depression and ED symptoms. Higher scores in mental health and low perception of burden at baseline predicted improved caregiver QoL at 1-year follow-up. The caregivers' QoL improved if the perception of burden decreased over time and if depression of the patient improved. The results suggest that interventions directed to reduce the caregivers' perception of burden and to improve the mental health of the ED patients would lead to improved caregiver QoL. The high attrition rate at T2 made prediction analyses unviable. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  9. Sport activities differentiating match-play improvement in elite youth footballers - a 2-year longitudinal study.

    PubMed

    Güllich, Arne; Kovar, Peter; Zart, Sebastian; Reimann, Ansgar

    2017-02-01

    This study examined contributions of different types of sport activities to the development of elite youth soccer performance. Match-play performance of 44 German male players was assessed by expert coaches twice, 24 months apart (age 11.1-13.1 years), based on videotaped 5v5 matches. Player pairs were matched by identical age and initial performance at t 1 . Each player was assigned to a group of either "Strong" or "Weak Responders" based on a higher or lower subsequent performance improvement at t 2 within each pair (mean Δperformance 29% vs. 7%). A questionnaire recorded current and earlier amounts of organised practice/training and non-organised sporting play, in soccer and other sports, respectively. Group comparison revealed that "Strong Responders" accumulated more non-organised soccer play and organised practice/training in other sports, but not more organised soccer practice/training. Subsequent multivariate analyses (multiple linear regression analyses (MLR)) highlighted that higher resultant match-play performance at t 2 was accounted for R 2 adj  = 0.65 by performance at t 1 , together with more non-organised soccer play and organised engagement in other sports, respectively, and greater current, but less earlier volume of organised soccer. The findings suggest that variable early sporting experience facilitates subsequent soccer performance development in German elite youth footballers.

  10. Physical activity and depression: a large cross-sectional, population-based study across 36 low- and middle-income countries.

    PubMed

    Stubbs, B; Koyanagi, A; Schuch, F B; Firth, J; Rosenbaum, S; Veronese, N; Solmi, M; Mugisha, J; Vancampfort, D

    2016-12-01

    Physical activity (PA) is good for health, yet several small-scale studies have suggested that depression is associated with low PA. A paucity of nationally representative studies investigating this relationship exists, particularly in low- and middle-income countries (LMICs). This study explored the global association of PA with depression and its mediating factors. Participants from 36 LMICs from the World Health Survey were included. Multivariable logistic regression analyses were undertaken exploring the relationship between PA and depression. Across 178 867 people (mean ± SD age = 36.2 ± 13.5 years; 49.9% male), the prevalence of depression and the prevalence of low PA were 6.6% and 16.8% respectively. The prevalence of low PA was significantly higher among those with depression vs. no depression (26.0% vs. 15.8%, P < 0.0001). In the adjusted model, depression was associated with higher odds for low PA (OR = 1.42; 95% CI = 1.24-1.63). Mediation analyses demonstrated that low PA among people with depression was explained by mobility limitations (40.3%), pain and discomfort (35.8%), disruptions in sleep and energy (25.2%), cognition (19.4%) and vision (10.9%). Individuals with depression engage in lower levels of PA in LMICs. Future longitudinal research is warranted to better understand the relationships observed. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. The source and impact of appearance teasing: an examination by sex and weight status among early adolescents from the Czech Republic.

    PubMed

    Almenara, Carlos A; Ježek, Stanislav

    2015-03-01

    Some adolescents are victims of negative appearance-related feedback, and this may have lasting adverse effects on their self-evaluation. The aim of this study was to examine the frequency and impact of appearance teasing across sex and weight status. The participants were 570 Czech adolescents (47.9% girls) evaluated at age 13 during the European Longitudinal Study of Pregnancy and Childhood. Instruments used were body mass index and an adapted version of the Physical Experiences Survey that measures appearance teasing sources (parents, peers, among others), body part teased, and the impact of teasing. Chi-square test and multivariate analyses of variance were conducted to compare groups by sex and weight status. Logistic regression was then used for adjusted analyses. Girls were more likely to report appearance teasing than boys. Overweight adolescents, both girls and boys, were more likely to be teased than non-overweight adolescents. Overweight adolescents compared with non-overweight adolescents reported higher levels of impact of body-related teasing. Czech adolescents continue to adopt the societal standards of Western countries, stigmatizing overweight peers. This may affect more obese adolescents. Future research has to evaluate different sources of appearance-related teasing. Interventions in schools are suitable for the reduction of appearance-related prejudices. © 2015, American School Health Association.

  12. Social Information Processing Mechanisms and Victimization: A Literature Review.

    PubMed

    van Reemst, Lisa; Fischer, Tamar F C; Zwirs, Barbara W C

    2016-01-01

    The aim of the current literature review, which is based on 64 empirical studies, was to assess to what extent mechanisms of the Social Information Processing (SIP) model of Crick and Dodge (1994) are related to victimization. The reviewed studies have provided support for the relation between victimization and several social information processing mechanisms, especially the interpretation of cues and self-efficacy (as part of the response decision). The relationship between victimization and other mechanisms, such as the response generation, was only studied in a few articles. Until now research has often focused on just one step of the model, instead of attempting to measure the associations between multiple mechanisms and victimization in multivariate analyses. Such analyses would be interesting to gain more insight into the SIP model and its relationship with victimization. The few available longitudinal studies show that mechanisms both predict victimization (internal locus of control, negative self-evaluations and less assertive response selection) and are predicted by victimization (hostile attribution of intent and negative evaluations of others). Associations between victimization and SIP mechanisms vary across different types and severity of victimization (stronger in personal and severe victimization), and different populations (stronger among young victims). Practice could focus on these stronger associations and the interpretation of cues. More research is needed however, to investigate whether intervention programs that address SIP mechanisms are suitable for victimization and all relevant populations. © The Author(s) 2014.

  13. Joint models for longitudinal and time-to-event data: a review of reporting quality with a view to meta-analysis.

    PubMed

    Sudell, Maria; Kolamunnage-Dona, Ruwanthi; Tudur-Smith, Catrin

    2016-12-05

    Joint models for longitudinal and time-to-event data are commonly used to simultaneously analyse correlated data in single study cases. Synthesis of evidence from multiple studies using meta-analysis is a natural next step but its feasibility depends heavily on the standard of reporting of joint models in the medical literature. During this review we aim to assess the current standard of reporting of joint models applied in the literature, and to determine whether current reporting standards would allow or hinder future aggregate data meta-analyses of model results. We undertook a literature review of non-methodological studies that involved joint modelling of longitudinal and time-to-event medical data. Study characteristics were extracted and an assessment of whether separate meta-analyses for longitudinal, time-to-event and association parameters were possible was made. The 65 studies identified used a wide range of joint modelling methods in a selection of software. Identified studies concerned a variety of disease areas. The majority of studies reported adequate information to conduct a meta-analysis (67.7% for longitudinal parameter aggregate data meta-analysis, 69.2% for time-to-event parameter aggregate data meta-analysis, 76.9% for association parameter aggregate data meta-analysis). In some cases model structure was difficult to ascertain from the published reports. Whilst extraction of sufficient information to permit meta-analyses was possible in a majority of cases, the standard of reporting of joint models should be maintained and improved. Recommendations for future practice include clear statement of model structure, of values of estimated parameters, of software used and of statistical methods applied.

  14. A survey of variable selection methods in two Chinese epidemiology journals

    PubMed Central

    2010-01-01

    Background Although much has been written on developing better procedures for variable selection, there is little research on how it is practiced in actual studies. This review surveys the variable selection methods reported in two high-ranking Chinese epidemiology journals. Methods Articles published in 2004, 2006, and 2008 in the Chinese Journal of Epidemiology and the Chinese Journal of Preventive Medicine were reviewed. Five categories of methods were identified whereby variables were selected using: A - bivariate analyses; B - multivariable analysis; e.g. stepwise or individual significance testing of model coefficients; C - first bivariate analyses, followed by multivariable analysis; D - bivariate analyses or multivariable analysis; and E - other criteria like prior knowledge or personal judgment. Results Among the 287 articles that reported using variable selection methods, 6%, 26%, 30%, 21%, and 17% were in categories A through E, respectively. One hundred sixty-three studies selected variables using bivariate analyses, 80% (130/163) via multiple significance testing at the 5% alpha-level. Of the 219 multivariable analyses, 97 (44%) used stepwise procedures, 89 (41%) tested individual regression coefficients, but 33 (15%) did not mention how variables were selected. Sixty percent (58/97) of the stepwise routines also did not specify the algorithm and/or significance levels. Conclusions The variable selection methods reported in the two journals were limited in variety, and details were often missing. Many studies still relied on problematic techniques like stepwise procedures and/or multiple testing of bivariate associations at the 0.05 alpha-level. These deficiencies should be rectified to safeguard the scientific validity of articles published in Chinese epidemiology journals. PMID:20920252

  15. Recent im/migration to Canada linked to unmet health needs among sex workers in Vancouver, Canada: Findings of a longitudinal study

    PubMed Central

    Sou, Julie; Goldenberg, Shira M.; Duff, Putu; Nguyen, Paul; Shoveller, Jean; Shannon, Kate

    2017-01-01

    Despite universal health care in Canada, sex workers (SW) and im/migrants experience suboptimal health care access. In this analysis, we examined the correlates of unmet health needs among SWs in Metro Vancouver over time. Data from a longitudinal cohort of women SWs (AESHA) was used. Of 742 SWs, 25.5% reported unmet health needs at least once over the 4-year study period. In multivariable logistic regression using generalized estimating equations, recent im/migration had the strongest impact on unmet health needs; long-term im/migration, policing, and trauma were also important determinants. Legal and social supports to promote im/migrant SWs’ access to health care are recommended. PMID:28300492

  16. Modeling the High Speed Research Cycle 2B Longitudinal Aerodynamic Database Using Multivariate Orthogonal Functions

    NASA Technical Reports Server (NTRS)

    Morelli, E. A.; Proffitt, M. S.

    1999-01-01

    The data for longitudinal non-dimensional, aerodynamic coefficients in the High Speed Research Cycle 2B aerodynamic database were modeled using polynomial expressions identified with an orthogonal function modeling technique. The discrepancy between the tabular aerodynamic data and the polynomial models was tested and shown to be less than 15 percent for drag, lift, and pitching moment coefficients over the entire flight envelope. Most of this discrepancy was traced to smoothing local measurement noise and to the omission of mass case 5 data in the modeling process. A simulation check case showed that the polynomial models provided a compact and accurate representation of the nonlinear aerodynamic dependencies contained in the HSR Cycle 2B tabular aerodynamic database.

  17. Lung cancer incidence and survival among HIV-infected and uninfected women and men.

    PubMed

    Hessol, Nancy A; Martínez-Maza, Otoniel; Levine, Alexandra M; Morris, Alison; Margolick, Joseph B; Cohen, Mardge H; Jacobson, Lisa P; Seaberg, Eric C

    2015-06-19

    To determine the lung cancer incidence and survival time among HIV-infected and uninfected women and men. Two longitudinal studies of HIV infection in the United States. Data from 2549 women in the Women's Interagency HIV Study (WIHS) and 4274 men in the Multicenter AIDS Cohort Study (MACS), all with a history of cigarette smoking, were analyzed. Lung cancer incidence rates and incidence rate ratios were calculated using Poisson regression analyses. Survival time was assessed using Kaplan-Meier and Cox proportional-hazard analyses. Thirty-seven women and 23 men developed lung cancer (46 HIV-infected and 14 HIV-uninfected) during study follow-up. In multivariable analyses, the factors that were found to be independently associated with a higher lung cancer incidence rate ratios were older age, less education, 10 or more pack-years of smoking, and a prior diagnosis of AIDS pneumonia (vs. HIV-uninfected women). In an adjusted Cox model that allowed different hazard functions for each cohort, a history of injection drug use was associated with shorter survival, and a lung cancer diagnosis after 2001 was associated with longer survival. In an adjusted Cox model restricted to HIV-infected participants, nadir CD4 lymphocyte cell count less than 200 was associated with shorter survival time. Our data suggest that pulmonary damage and inflammation associated with HIV infection may be causative for the increased risk of lung cancer. Encouraging and assisting younger HIV-infected smokers to quit and to sustain cessation of smoking is imperative to reduce the lung cancer burden in this population.

  18. National Longitudinal Study of the High School Class of 1972: A Summary of the Merged Findings from Analyses by RTI of the First Follow-Up and Preceding Data. RTI Concept Paper No. CP-22-75-07.

    ERIC Educational Resources Information Center

    Research Triangle Inst., Durham, NC. Center for Educational Research and Evaluation.

    An overview of the National Longitudinal Study of the High School Class of 1972 (NLS) is provided. Section one describes the research design for the base-year and first through third followup surveys. Section two summarizes findings from data analyses of the first followup and base-year, completed before September 1975. The findings are presented…

  19. Longitudinal relationship of parental hypertension with body mass index, blood pressure, and cardiovascular reactivity in children.

    PubMed

    Li, Rongling; Alpert, Bruce S; Walker, Sammie S; Somes, Grant W

    2007-05-01

    To investigate whether parental hypertension (HTN) affects children's body mass index (BMI) and cardiovascular reactivity (CVR) over time. A longitudinal study of 315 students (black: 23 females, 19 males; white: 142 females, 131 males) was conducted in the public schools of Obion County, Tennessee, between 1987 and 1992. BMI and BMI z scores were calculated. The CVR task was a series of video games (taking approximately 10 minutes to play) given to the same students in their third-, fourth-, fifth-, seventh-, and eighth-grade years. CVR was defined as the change in blood pressure (delta_BP) or heart rate (delta_HR) between before playing and while playing the video game. Positive parental history of HTN (27.6%) was defined as at least 1 parent with HTN. Multivariable regression analyses were performed to estimate the effects of parental HTN on children's BMI and CVR over time. Children with parental HTN had significant higher BMI, BMI z score, and R_BP than did children without parental HTN (BMI: 21.6 vs 19.9, P = .001; BMI z score: 1.6 vs 1.1, P = .003; R_SBP: 112.6 vs 110.4 mm Hg, P = .01; R_DBP 62.7 vs 60.6 mm Hg, P = .003) after adjustment for covariates. Increased CVR was observed in children with parental HTN compared with children without parental HTN but was statistically significant only for SBP (delta_SBP: 17.2 vs 14.9 mm Hg; P = .01) after adjustment for covariates. Parental HTN independently predicted children's BMI, BMI z score, resting BP, and BP reactivity.

  20. Predictors of six month change in the voice handicap index in a treatment seeking population

    PubMed Central

    Moore, Jaime; Greenberg, Caprice

    2016-01-01

    Objective To evaluate predictors of longitudinal change in patient-perceived voice impact as determined by the Voice Handicap Index (VHI). Study Design Prospective, survey study. Methods Patients consented to the UW Voice and Swallow Clinics Outcomes Database with voice, breathing and/or cough concerns with a baseline clinic visit from November 2012 to January 2014 were eligible for the study. VHI was sent to patients six months post-clinic visit to determine change in voice handicap from baseline. General health was screened using the SF-12v2 survey, using physical component (PCS) and mental component summary (MCS) scores. Predictor variables included – treatment (medical and/or behavioral), dysphonia sub-diagnosis, GRBAS rating, age, sex, socioeconomic factors, smoking history, and comorbidity score. Results Two-hundred thirty-seven patients met study criteria and were followed longitudinally. Eighty-two patients returned six month surveys. VHI was significantly correlated with MCS scores. Patients with a higher grade in baseline GRBAS score were more likely to receive voice intervention (p = .04). Six-month improvement in VHI score was associated with both higher initial VHI score and higher education level in both univariate (p < .01, p = .04) and multivariate analyses (p < .01, p = .02). Voice treatment (medical and/or behavioral) was not a significant factor for improvement in VHI. Conclusions Our results suggest it is important to consider baseline self-perceived voice impact measures and education level in setting expectations for voice treatment. Future studies examining the relationship between treatment patterns and voice-related patient outcomes are warranted. PMID:26952321

  1. Internet use and cancer-preventive behaviors in older adults: findings from a longitudinal cohort study.

    PubMed

    Xavier, Andre Junqueira; d'Orsi, Eleonora; Wardle, Jane; Demakakos, Panayotes; Smith, Samuel G; von Wagner, Christian

    2013-11-01

    The Internet is a key provider of health information, but little is known about its associations with cancer-preventive behaviors. This study investigated the associations between Internet use and cancer-preventive behaviors among older adults. Data were taken from Waves 1 to 5 (2002-2011) of the English Longitudinal Study of Aging, a cohort study of men and women 50 years or older in England, United Kingdom. Internet use was recorded at each wave. Breast and colorectal screening, fruit and vegetable consumption, physical activity, and smoking were recorded at Wave 5. Social, cognitive, and physical function variables recorded at Wave 1 were analyzed as predictors of Internet use and included as covariates in analyses linking Internet use to behavior. Of 5,943 respondents, 41.4% did not report any Internet use, 38.3% reported using it in one to three waves ("intermittent users"), and 20.3% used it in all waves ("consistent users"). Internet use was higher in younger, male, White, wealthier, more educated respondents, and those without physical limitations. Multivariable analysis showed that consistent users were more likely than "never users" to report CRC screening, weekly moderate/vigorous physical activity, and five or more daily servings of fruit and vegetables, and less likely to report smoking. There was no significant association between Internet use and breast screening. Internet use showed a quantitative association with cancer-preventive behaviors even after controlling for various social, cognitive, and physical correlates of Internet use. Promoting Internet use among older adults from all backgrounds could contribute to improving cancer outcomes and reducing inequalities. ©2013 AACR.

  2. Attachment to Conventional Institutions and Adolescent Rapid Repeat Pregnancy: A Longitudinal National Study Among Adolescents in the United States.

    PubMed

    Reese, Bianka M; Halpern, Carolyn T

    2017-01-01

    Introduction There is limited research on rapid repeat pregnancies (RRP) among adolescents, especially using nationally representative samples. We examine distal factors-school, family, peers, and public/private religious ties-and their associations with RRP among adolescent mothers. Methods Guided by social development theory, we conducted multivariate logistic regression analyses, adjusted for sociodemographic characteristics, to examine associations between RRP and attachment to school, family, peers, and religion among 1158 female respondents from the National Longitudinal Study of Adolescent to Adult Health (Add Health) who reported at least one live birth before age 20. Results Attachments to conventional institutions were associated with lower likelihood of RRP. Adolescent mothers who had a stronger relationship with their parents had reduced odds of RRP (adjusted odds ratio [aOR] 0.83, 95 % CI 0.71-0.99). Increased odds of RRP were associated with anticipating fewer negative social consequences of sex (aOR 1.18, 95 % CI 1.02-1.35), never praying (versus praying daily; aOR 1.47, 95 % CI 1.10-1.96), and never participating in church-related youth activities (versus participating once a week; 1.04, 95 % CI 1.01-1.07). Discussion After an adolescent birth, social support from family, peers, and the community can benefit young mothers. Private aspects of religiosity may be especially important. Understanding the processes by which these distal factors are linked to the likelihood of RRP is needed to create multifaceted intervention programs that provide diverse methods of support customized to specific circumstances of adolescent mothers.

  3. Attachment to Conventional Institutions and Adolescent Rapid Repeat Pregnancy: A Longitudinal National Study among Adolescents in the United States

    PubMed Central

    Reese, Bianka M.; Halpern, Carolyn T.

    2016-01-01

    Introduction There is limited research on rapid repeat pregnancies (RRP) among adolescents, especially using nationally representative samples. We examine distal factors—school, family, peers, and public/private religious ties—and their associations with RRP among adolescent mothers. Methods Guided by social development theory, we conducted multivariate logistic regression analyses, adjusted for sociodemographic characteristics, to examine associations between RRP and attachment to school, family, peers, and religion among 1,158 female respondents from the National Longitudinal Study of Adolescent to Adult Health (Add Health) who reported at least one live birth before age 20. Results Attachments to conventional institutions were associated with lower likelihood of RRP. Adolescent mothers who had a stronger relationship with their parents had reduced odds of RRP (adjusted odds ratio [aOR] 0.83, 95% CI 0.71-0.99). Increased odds of RRP were associated with anticipating fewer negative social consequences of sex (aOR 1.18, 95% CI 1.02-1.35), never praying (versus praying daily; aOR 1.47, 95% CI 1.10-1.96), and never participating in church-related youth activities (versus participating once a week; 1.04, 95% CI 1.01-1.07). Discussion After an adolescent birth, social support from family, peers, and the community can benefit young mothers. Private aspects of religiosity may be especially important. Understanding the processes by which these distal factors are linked to the likelihood of RRP is needed to create multifaceted intervention programs that provide diverse methods of support customized to specific circumstances of adolescent mothers. PMID:27475827

  4. The Association Between Familial Homelessness, Aggression, and Victimization Among Children.

    PubMed

    Jetelina, Katelyn K; Reingle Gonzalez, Jennifer M; Cuccaro, Paula M; Peskin, Melissa F; Elliott, Marc N; Coker, Tumaini R; Mrug, Sylvie; Davies, Susan L; Schuster, Mark A

    2016-12-01

    The purpose of this study was to evaluate the relationship between the number of periods children were exposed to familial homelessness and childhood aggression and victimization. Survey data were obtained from 4,297 fifth-grade children and their caregivers in three U.S. cities. Children and primary caregivers were surveyed longitudinally in 7th and 10th grades. Family homelessness, measured at each wave as unstable housing, was self-reported by the caregiver. Children were categorized into four mutually exclusive groups: victim only, aggressor only, victim-aggressor, and neither victim nor aggressor at each time point using validated measures. Multinomial, multilevel mixed models were used to evaluate the relationship among periods of homelessness and longitudinal victimization, aggression, and victim aggression compared to children who were nonvictims and nonaggressors. Results suggest that children who experienced family homelessness were more likely than domiciled children to report aggression and victim aggression but not victimization only. Multivariate analyses suggested that even brief periods of homelessness were positively associated with aggression and victim aggression (relative to neither) compared to children who were never homeless. Furthermore, childhood victimization and victim aggression significantly decreased from 5th grade to 10th grade while aggression significantly increased in 10th grade. Children who experienced family homelessness for brief periods of time were significantly more likely to be a victim-aggressor or aggressor compared to those who were never homeless. Prevention efforts should target housing security and other important factors that may reduce children's likelihood of aggression and associated victimization. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  5. Importance of early weight changes to predict long-term weight gain during psychotropic drug treatment.

    PubMed

    Vandenberghe, Frederik; Gholam-Rezaee, Mehdi; Saigí-Morgui, Núria; Delacrétaz, Aurélie; Choong, Eva; Solida-Tozzi, Alessandra; Kolly, Stéphane; Thonney, Jacques; Gallo, Sylfa Fassassi; Hedjal, Ahmed; Ambresin, Anne-Emmanuelle; von Gunten, Armin; Conus, Philippe; Eap, Chin B

    2015-11-01

    Psychotropic drugs can induce substantial weight gain, particularly during the first 6 months of treatment. The authors aimed to determine the potential predictive power of an early weight gain after the introduction of weight gain-inducing psychotropic drugs on long-term weight gain. Data were obtained from a 1-year longitudinal study ongoing since 2007 including 351 psychiatric (ICD-10) patients, with metabolic parameters monitored (baseline and/or 1, 3, 6, 9, 12 months) and with compliance ascertained. International Diabetes Federation and World Health Organization definitions were used to define metabolic syndrome and obesity, respectively. Prevalences of metabolic syndrome and obesity were 22% and 17%, respectively, at baseline and 32% and 24% after 1 year. Receiver operating characteristic analyses indicated that an early weight gain > 5% after a period of 1 month is the best predictor for important long-term weight gain (≥ 15% after 3 months: sensitivity, 67%; specificity, 88%; ≥ 20% after 12 months: sensitivity, 47%; specificity, 89%). This analysis identified most patients (97% for 3 months, 93% for 12 months) who had weight gain ≤ 5% after 1 month as continuing to have a moderate weight gain after 3 and 12 months. Its predictive power was confirmed by fitting a longitudinal multivariate model (difference between groups in 1 year of 6.4% weight increase as compared to baseline, P = .0001). Following prescription of weight gain-inducing psychotropic drugs, a 5% threshold for weight gain after 1 month should raise clinician concerns about weight-controlling strategies. © Copyright 2015 Physicians Postgraduate Press, Inc.

  6. The association between socioeconomic status and disability after stroke: findings from the Adherence eValuation After Ischemic stroke Longitudinal (AVAIL) registry.

    PubMed

    Bettger, Janet Prvu; Zhao, Xin; Bushnell, Cheryl; Zimmer, Louise; Pan, Wenqin; Williams, Linda S; Peterson, Eric D

    2014-03-26

    Stroke is the leading cause of disability among adults in the United States. The association of patients' pre-event socioeconomic status (SES) with post-stroke disability is not well understood. We examined the association of three indicators of SES--educational attainment, working status, and perceived adequacy of household income--with disability 3-months following an acute ischemic stroke. We conducted retrospective analyses of a prospective cohort of 1965 ischemic stroke patients who survived to 3 months in the Adherence eValuation After Ischemic stroke--Longitudinal (AVAIL) study. Multivariable logistic regression was used to examine the relationship of level of education, pre-stroke work status, and perceived adequacy of household income with disability (defined as a modified Rankin Scale of 3-5 indicating activities of daily living limitations or constant care required). Overall, 58% of AVAIL stroke patients had a high school or less education, 61% were not working, and 27% perceived their household income as inadequate prior to their stroke. Thirty five percent of patients were disabled at 3-months. After adjusting for demographic and clinical factors, stroke survivors who were unemployed or homemakers, disabled and not-working, retired, less educated, or reported to have inadequate income prior to their stroke had a significantly higher odds of post-stroke disability. In this cohort of stroke survivors, socioeconomic status was associated with disability following acute ischemic stroke. The results may have implications for public health and health service interventions targeting stroke survivors at risk of poor outcomes.

  7. Factors Associated with the Persistence of Bullying Victimization From 10th grade to 13th Grade: A Longitudinal Study.

    PubMed

    Lien, Lars; Welander-Vatn, Audun

    2013-01-01

    Bullying among adolescents represents a major public health challenge. The aim of this study was to map the stability of bullying victimization across the transitional phase from lower to upper secondary school, and to describe the sociodemographic, academic and health-related characteristics of those bullied during the transition. 3674 Norwegian adolescents were followed longitudinally from the age of 15/16 until the age of 18/19, answering questionnaires about health, academic achievements, life events, lifestyle and sociodemography. The 337 participants reporting exposure to bullying victimization at age 15/16 were the target group, as we made comparisons between those reporting victimization only at the age of 15/16 (n=289) with the participants for whom the bullying had continued into later adolescence (n = 48). 14% of those victimized at age 15/16, reported continuation of bullying victimization into upper secondary school. These adolescents were significantly more likely to report having divorced parents, low parental educational level, poor self-perceived economy, muscle and skeletal pain, symptoms of mental distress, lower school marks in Norwegian and higher body-mass index (BMI) when group differences at age 18/19 were assessed through basic inferential statistical tests. However, the multivariate logistic regression analyses only revealed statistically significantly increased adjusted odds ratios for the variables mental distress and school-marks in Norwegian. The persistence of exposure to bullying from 10th grade to 13th grade is associated with mental health complaints and poor school performance. Preventive measures to take care of students being continuously bullied should be in place in secondary schools.

  8. Relationship of Office and Ambulatory Blood Pressure With Left Ventricular Global Longitudinal Strain.

    PubMed

    Sera, Fusako; Jin, Zhezhen; Russo, Cesare; Lee, Edward S; Schwartz, Joseph E; Rundek, Tatjana; Elkind, Mitchell S V; Homma, Shunichi; Sacco, Ralph L; Di Tullio, Marco R

    2016-11-01

    Left ventricular (LV) global longitudinal strain (GLS) is an early indicator of subclinical cardiac dysfunction, even when LV ejection fraction (LVEF) is normal, and is an independent predictor of cardiovascular events. Ambulatory blood pressure (BP) is a better predictor of cardiovascular events, including heart failure, than office BP. We investigated the association of office and ambulatory BP measurements with subclinical LV systolic dysfunction in a community-based cohort with normal LVEF. Two-dimensional speckle-tracking echocardiography and 24-hour ambulatory BP monitoring were performed in 577 participants (mean age 70±9 years; 60% women) with LVEF ≥50% from the Cardiovascular Abnormalities and Brain Lesions (CABL) study. Univariable and multivariable linear regression analyses were used to assess the associations of BP measures with GLS. Higher ambulatory and office BP values were consistently associated with impaired GLS. After adjustment for pertinent covariates (age, sex, race/ethnicity, body mass index, diabetes mellitus, coronary artery disease, LV mass index, and antihypertensive medication), office diastolic BP and ambulatory systolic and diastolic BPs (24-hour, daytime and nighttime) were independently associated with GLS (P = 0.003 for office DBP, P ≤ 0.001 for all ambulatory BPs). When ambulatory and office BP values were included in the same model, all ambulatory BP measures remained significantly associated with GLS (all P < 0.01), whereas office BP values were not. Ambulatory BP values are significantly associated with impaired GLS and the association is stronger than for office BP. Ambulatory BP monitoring might have a role in the risk stratification of hypertensive patients for early LV dysfunction.

  9. The relationship between childhood weight, dental caries and eating practices in children aged 4-8 years in Australia, 2004-2008.

    PubMed

    Hooley, M; Skouteris, H; Millar, L

    2012-12-01

    The association between overweight/obesity and dental caries in children is contentious with studies variously reporting positive or negative associations between the two conditions. Since 1995, Australia has experienced a rise in the prevalence of both conditions in its children. This study investigated the association between child weight, diet and dental problems in a nationally representative sample. Data from 4149 children (51.5% male) participating in the Longitudinal Study of Australian Children (LSAC) were used. The LSAC is a longitudinal study collecting data from a large representative cohort of Australian children; data from the first three waves were included with children aged 4-5 years, 6-7 years, and 8-9 years. Multivariate cross-sectional and prospective analyses were conducted to determine the relationships between child weight, diet and dental problems. Overweight/obesity was associated with sweet drink consumption and dental problems associated with consumption of fatty foods and sweet drinks. Underweight was associated with dental problems cross-sectionally, but both underweight and overweight at age 6-7 years predicted dental problems at age 8-9 years. Dental caries and body weight are influenced by diet. Overweight children may be consuming less fatty food but appear to be consuming more sweet drinks than normal-weight children, which can lead to both increased weight and dental caries. Dietary interventions designed to reduce the development of dental caries may also reduce the development and maintenance of overweight. © 2012 The Authors. Pediatric Obesity © 2012 International Association for the Study of Obesity.

  10. The Effect of Patient and Surgical Characteristics on Renal Function After Partial Nephrectomy.

    PubMed

    Winer, Andrew G; Zabor, Emily C; Vacchio, Michael J; Hakimi, A Ari; Russo, Paul; Coleman, Jonathan A; Jaimes, Edgar A

    2018-06-01

    The purpose of the study was to identify patient and disease characteristics that have an adverse effect on renal function after partial nephrectomy. We conducted a retrospective review of 387 patients who underwent partial nephrectomy for renal tumors between 2006 and 2014. A line plot with a locally weighted scatterplot smoothing was generated to visually assess renal function over time. Univariable and multivariable longitudinal regression analyses incorporated a random intercept and slope to evaluate the association between patient and disease characteristics with renal function after surgery. Median age was 60 years and most patients were male (255 patients [65.9%]) and white (343 patients [88.6%]). In univariable analysis, advanced age at surgery, larger tumor size, male sex, longer ischemia time, history of smoking, and hypertension were significantly associated with lower preoperative estimated glomerular filtration rate (eGFR). In multivariable analysis, independent predictors of reduced renal function after surgery included advanced age, lower preoperative eGFR, and longer ischemia time. Length of time from surgery was strongly associated with improvement in renal function among all patients. Independent predictors of postoperative decline in renal function include advanced age, lower preoperative eGFR, and longer ischemia time. A substantial number of subjects had recovery in renal function over time after surgery, which continued past the 12-month mark. These findings suggest that patients who undergo partial nephrectomy can experience long-term improvement in renal function. This improvement is most pronounced among younger patients with higher preoperative eGFR. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Rap Music Use, Perceived Peer Behavior, and Sexual Initiation Among Ethnic Minority Youth.

    PubMed

    Johnson-Baker, Kimberly A; Markham, Christine; Baumler, Elizabeth; Swain, Honora; Emery, Susan

    2016-03-01

    Research shows that rap music use is associated with risky sexual behavior in ethnic minority youth; however, it is unknown whether rap music use impacts sexual initiation specifically and, if so, which factors mediate this impact. Thus, we investigated the longitudinal relationship between hours spent listening to rap music in seventh grade and sexual initiation in ninth grade. We also examined the role of perceived peer sexual behavior as a potential mediator of this relationship. We analyzed data from students (n = 443) enrolled in a school-based randomized controlled trial of a sexual health education curriculum collected at baseline and at 18-month follow-up. Rap music use and perceived peer sexual behavior were assessed in seventh grade, whereas sexual initiation was assessed in ninth grade. Univariate, multivariate, and mediation analyses were conducted. At baseline, rap music use was significantly associated with race/ethnicity, parental music rules, and sexual behavior, but not with gender or parental education. Rap music use was a significant predictor of sexual initiation on univariate analysis but not multivariate analysis. Mediation analysis showed that the association between hours spent listening to rap music and sexual initiation was significantly mediated by perceived peer sexual behavior. Rap music use in early adolescence significantly impacts sexual initiation in late adolescence, partially mediated by perceived peer sexual behavior. More research is needed to understand how rap music influences perceptions of peer sexual behavior, which, in turn, influence early sexual initiation. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  12. Gender, childhood and adult socioeconomic inequalities in functional disability among Chinese older adults.

    PubMed

    Zhong, Yaqin; Wang, Jian; Nicholas, Stephen

    2017-09-02

    Gender difference and life-course socioeconomic inequalities in functional disability may exist among older adults. However, the association is less well understood among Chinese older population. The objective is to provide empirical evidences on this issue by exploring the association between gender, childhood and adult socioeconomic inequalities in functional disability. Data from the 2013 wave of the China Health and Retirement Longitudinal Study (CHARLS) was utilized. Functional disability was assessed by the activities of daily living (ADL) and instrumental activities of daily living (IADL). Childhood socioeconomic status (SES) was measured by birthplace, father's education and occupation. Adult SES was measured in terms of education and household income. Multivariate logistic regressions were conducted to assess the association between gender, childhood and adult SES and functional disability. Based on a sample of 18,448 older adults aged 45 years old and above, our results showed that the prevalence of ADL and IADL disability was higher among women than men, but gender difference disappeared after adult SES and adult health were controlled. Harsh conditions during childhood were associated with functional disability but in multivariate analyses only father's education was associated with IADL disability (OR for no education = 1.198; 95% CI = 1.062-1.353). Current SES such as higher education and good economic situation are protective factors of functional disability. Childhood and adult SES were both related to functional disability among older adults. Our findings highlight the need for policies and programs aimed at decreasing social inequalities during childhood and early adulthood, which could reduce socioeconomic inequalities in functional disability in later life.

  13. An exploratory factor analysis of nutritional biomarkers associated with major depression in pregnancy

    PubMed Central

    Bodnar, Lisa M.; Wisner, Katherine L.; Luther, James F.; Powers, Robert W.; Evans, Rhobert W.; Gallaher, Marcia J.; Newby, P.K.

    2011-01-01

    Objective Major depressive disorder (MDD) during pregnancy increases the risk of adverse maternal and infant outcomes. Maternal nutritional status may be a modifiable risk factor for antenatal depression. We evaluated the association between patterns in mid-pregnancy nutritional biomarkers and MDD. Design Prospective cohort study Setting Pittsburgh, Pennsylvania, USA Subjects Women who enrolled at ≤20 weeks gestation had a diagnosis of MDD made with the Structured Clinical Interview for DSM-IV at 20-, 30-, and 36-week study visits. A total of 135 women contributed 345 person-visits. Non-fasting blood drawn at enrollment was assayed for red cell essential fatty acids, plasma folate, homocysteine, and ascorbic acid; serum 25-hydroxyvitamin D, retinol, vitamin E, carotenoids, ferritin, and soluble transferrin receptors. Nutritional biomarkers were entered into principal components analysis. Results Three factors emerged: Factor 1, Essential Fatty Acids; Factor 2, Micronutrients; and Factor 3, Carotenoids. MDD was prevalent in 21.5% of women. In longitudinal multivariable logistic models, there was no association between the Essential Fatty Acid or Micronutrient patterns and MDD either before or after adjustment for employment, education, or prepregnancy BMI. In unadjusted analysis, women with Carotenoid factor scores in the middle and upper tertiles were 60% less likely than women in the bottom tertile to have MDD during pregnancy, but after adjustment for confounders, the associations were no longer statistically significant. Conclusions While meaningful patterns were derived using nutritional biomarkers, significant associations with MDD were not observed in multivariable adjusted analyses. Larger, more diverse samples are needed to understand nutrition-depression relationships during pregnancy. PMID:22152590

  14. Psychosocial work conditions, social participation and social capital: a causal pathway investigated in a longitudinal study.

    PubMed

    Lindström, Martin

    2006-01-01

    Social capital is often claimed to be promoted by stable social structures such as low migration rates between neighbourhoods and social networks that remain stable over time. However, stable social structures may also inhibit the formation of social capital in the form of social networks and social participation. One example is psychosocial conditions at work, which may be determined by characteristics such as demand and control in the work situation. The study examines the active workforce subpopulation within the Swedish Malmö Shoulder Neck Study. A total of 7836 individuals aged 45-69 years, were interviewed at baseline between 1992 and 1994, and at a 1-year follow-up. Four groups of baseline psychosocial work conditions categories defined by the Karasek-Theorell model (jobstrain, passive, active, relaxed) were analysed according to 13 different social participation items during the past year reported at the 1-year follow-up. Odds ratios and 95% confidence intervals with the jobstrain group as a reference were estimated. A multivariate logistic regression model was used to assess differences in different aspects of social participation between the four psychosocial work conditions groups. The results show that the respondents within the active category in particular but also the relaxed category, have significantly higher participation in many of the 13 social participation items, even after multivariate adjustments. The results strongly suggest that psychosocial work conditions may be an important determinant of social capital measured as social participation, a finding of immediate public health relevance because of the well known positive association between social participation and health-related behaviours.

  15. An exploratory factor analysis of nutritional biomarkers associated with major depression in pregnancy.

    PubMed

    Bodnar, Lisa M; Wisner, Katherine L; Luther, James F; Powers, Robert W; Evans, Rhobert W; Gallaher, Marcia J; Newby, P K

    2012-06-01

    Major depressive disorder (MDD) during pregnancy increases the risk of adverse maternal and infant outcomes. Maternal nutritional status may be a modifiable risk factor for antenatal depression. We evaluated the association between patterns in mid-pregnancy nutritional biomarkers and MDD. Prospective cohort study. Pittsburgh, Pennsylvania, USA. Women who enrolled at ≤20 weeks' gestation and had a diagnosis of MDD made with the Structured Clinical Interview for DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th edition) at 20-, 30- and 36-week study visits. A total of 135 women contributed 345 person-visits. Non-fasting blood drawn at enrolment was assayed for red cell essential fatty acids, plasma folate, homocysteine and ascorbic acid; serum 25-hydroxyvitamin D, retinol, vitamin E, carotenoids, ferritin and soluble transferrin receptors. Nutritional biomarkers were entered into principal components analysis. Three factors emerged: Factor 1, Essential Fatty Acids; Factor 2, Micronutrients; and Factor 3, Carotenoids. MDD was prevalent in 21·5 % of women. In longitudinal multivariable logistic models, there was no association between the Essential Fatty Acids or Micronutrients pattern and MDD either before or after adjustment for employment, education or pre-pregnancy BMI. In unadjusted analysis, women with factor scores for Carotenoids in the middle and upper tertiles were 60 % less likely than women in the bottom tertile to have MDD during pregnancy, but after adjustment for confounders the associations were no longer statistically significant. While meaningful patterns were derived using nutritional biomarkers, significant associations with MDD were not observed in multivariable adjusted analyses. Larger, more diverse samples are needed to understand nutrition-depression relationships during pregnancy.

  16. Longitudinal relationships between antiretroviral treatment adherence and discrimination due to HIV-serostatus, race, and sexual orientation among African-American men with HIV.

    PubMed

    Bogart, Laura M; Wagner, Glenn J; Galvan, Frank H; Klein, David J

    2010-10-01

    African-Americans show worse HIV disease outcomes compared to Whites. Health disparities may be aggravated by discrimination, which is associated with worse health and maladaptive health behaviors. We examined longitudinal effects of discrimination on antiretroviral treatment adherence among 152 HIV-positive Black men who have sex with men. We measured adherence and discrimination due to HIV-serostatus, race/ethnicity, and sexual orientation at baseline and monthly for 6 months. Hierarchical repeated-measures models tested longitudinal effects of each discrimination type on adherence. Over 6 months, participants took 60% of prescribed medications on average; substantial percentages experienced discrimination (HIV-serostatus, 38%; race/ethnicity, 40%; and sexual orientation, 33%). Greater discrimination due to all three characteristics was significantly bivariately associated with lower adherence (all p's < 0.05). In the multivariate model, only racial discrimination was significant (p < 0.05). Efforts to improve HIV treatment adherence should consider the context of multiple stigmas, especially racism.

  17. Measurement of Temperament in Infancy.

    ERIC Educational Resources Information Center

    Rothbart, Mary Klevjord

    1981-01-01

    Describes the development of a parent-report to assess infant temperament and presents longitudinal findings. Scales were developed to measure activity level, soothability, fear, distress to limitations, smiling/laughter, and duration of orienting. Longitudinal analyses showed that stability in some scales was age-related. (Author/DB)

  18. Multiple Hypothesis Testing for Experimental Gingivitis Based on Wilcoxon Signed Rank Statistics

    PubMed Central

    Preisser, John S.; Sen, Pranab K.; Offenbacher, Steven

    2011-01-01

    Dental research often involves repeated multivariate outcomes on a small number of subjects for which there is interest in identifying outcomes that exhibit change in their levels over time as well as to characterize the nature of that change. In particular, periodontal research often involves the analysis of molecular mediators of inflammation for which multivariate parametric methods are highly sensitive to outliers and deviations from Gaussian assumptions. In such settings, nonparametric methods may be favored over parametric ones. Additionally, there is a need for statistical methods that control an overall error rate for multiple hypothesis testing. We review univariate and multivariate nonparametric hypothesis tests and apply them to longitudinal data to assess changes over time in 31 biomarkers measured from the gingival crevicular fluid in 22 subjects whereby gingivitis was induced by temporarily withholding tooth brushing. To identify biomarkers that can be induced to change, multivariate Wilcoxon signed rank tests for a set of four summary measures based upon area under the curve are applied for each biomarker and compared to their univariate counterparts. Multiple hypothesis testing methods with choice of control of the false discovery rate or strong control of the family-wise error rate are examined. PMID:21984957

  19. Sex Hormones and Sleep in Men and Women From the General Population: A Cross-Sectional Observational Study.

    PubMed

    Kische, Hanna; Ewert, Ralf; Fietze, Ingo; Gross, Stefan; Wallaschofski, Henri; Völzke, Henry; Dörr, Marcus; Nauck, Matthias; Obst, Anne; Stubbe, Beate; Penzel, Thomas; Haring, Robin

    2016-11-01

    Associations between sex hormones and sleep habits originate mainly from small and selected patient-based samples. We examined data from a population-based sample with various sleep characteristics and the major part of sex hormones measured by mass spectrometry. We used data from 204 men and 213 women of the cross-sectional Study of Health in Pomerania-TREND. Associations of total T (TT) and free T, androstenedione (ASD), estrone, estradiol (E2), dehydroepiandrosterone-sulphate, SHBG, and E2 to TT ratio with sleep measures (including total sleep time, sleep efficiency, wake after sleep onset, apnea-hypopnea index [AHI], Insomnia Severity Index, Epworth Sleepiness Scale, and Pittsburgh Sleep Quality Index) were assessed by sex-specific multivariable regression models. In men, age-adjusted associations of TT (odds ratio 0.62; 95% confidence interval (CI) 0.46-0.83), free T, and SHBG with AHI were rendered nonsignificant after multivariable adjustment. In multivariable analyses, ASD was associated with Epworth Sleepiness Scale (β-coefficient per SD increase in ASD: -0.71; 95% CI: -1.18 to -0.25). In women, multivariable analyses showed positive associations of dehydroepiandrosterone-sulphate with wake after sleep onset (β-coefficient: .16; 95% CI 0.03-0.28) and of E2 and E2 to TT ratio with Epworth Sleepiness Scale. Additionally, free T and SHBG were associated with AHI in multivariable models among premenopausal women. The present cross-sectional, population-based study observed sex-specific associations of androgens, E2, and SHBG with sleep apnea and daytime sleepiness. However, multivariable-adjusted analyses confirmed the impact of body composition and health-related lifestyle on the association between sex hormones and sleep.

  20. Analysis of longitudinal data from animals where some data are missing in SPSS

    PubMed Central

    Duricki, DA; Soleman, S; Moon, LDF

    2017-01-01

    Testing of therapies for disease or injury often involves analysis of longitudinal data from animals. Modern analytical methods have advantages over conventional methods (particularly where some data are missing) yet are not used widely by pre-clinical researchers. We provide here an easy to use protocol for analysing longitudinal data from animals and present a click-by-click guide for performing suitable analyses using the statistical package SPSS. We guide readers through analysis of a real-life data set obtained when testing a therapy for brain injury (stroke) in elderly rats. We show that repeated measures analysis of covariance failed to detect a treatment effect when a few data points were missing (due to animal drop-out) whereas analysis using an alternative method detected a beneficial effect of treatment; specifically, we demonstrate the superiority of linear models (with various covariance structures) analysed using Restricted Maximum Likelihood estimation (to include all available data). This protocol takes two hours to follow. PMID:27196723

  1. Developmental Origins of Low Mathematics Performance and Normal Variation in Twins from 7 to 9 Years

    PubMed Central

    Haworth, Claire M. A.; Kovas, Yulia; Petrill, Stephen A.; Plomin, Robert

    2009-01-01

    A previous publication reported the etiology of mathematics performance in 7-year-old twins (Oliver et al., 2004). As part of the same longitudinal study we investigated low mathematics performance and normal variation in a representative United Kingdom sample of 1713 same-sex 9-year-old twins based on teacher-assessed National Curriculum standards. Univariate individual differences and DeFries-Fulker extremes analyses were performed. Similar to our results at 7 years, all mathematics scores at 9 years showed high heritability (.62–.75) and low shared environmental estimates (.00–.11) for both the low performance group and the full sample. Longitudinal analyses were performed from 7 to 9 years. These longitudinal analyses indicated strong genetic continuity from 7 to 9 years for both low performance and mathematics in the normal range. We conclude that, despite the considerable differences in mathematics curricula from 7 to 9 years, the same genetic effects largely operate at the two ages. PMID:17539370

  2. Developmental origins of low mathematics performance and normal variation in twins from 7 to 9 years.

    PubMed

    Haworth, Claire M A; Kovas, Yulia; Petrill, Stephen A; Plomin, Robert

    2007-02-01

    A previous publication reported the etiology of mathematics performance in 7-year-old twins (Oliver et al., 2004). As part of the same longitudinal study we investigated low mathematics performance and normal variation in a representative United Kingdom sample of 1713 same-sex 9-year-old twins based on teacher-assessed National Curriculum standards. Univariate individual differences and DeFries-Fulker extremes analyses were performed. Similar to our results at 7 years, all mathematics scores at 9 years showed high heritability (.62-.75) and low shared environmental estimates (.00-.11) for both the low performance group and the full sample. Longitudinal analyses were performed from 7 to 9 years. These longitudinal analyses indicated strong genetic continuity from 7 to 9 years for both low performance and mathematics in the normal range. We conclude that, despite the considerable differences in mathematics curricula from 7 to 9 years, the same genetic effects largely operate at the two ages.

  3. Using a Multivariate Multilevel Polytomous Item Response Theory Model to Study Parallel Processes of Change: The Dynamic Association between Adolescents' Social Isolation and Engagement with Delinquent Peers in the National Youth Survey

    ERIC Educational Resources Information Center

    Hsieh, Chueh-An; von Eye, Alexander A.; Maier, Kimberly S.

    2010-01-01

    The application of multidimensional item response theory models to repeated observations has demonstrated great promise in developmental research. It allows researchers to take into consideration both the characteristics of item response and measurement error in longitudinal trajectory analysis, which improves the reliability and validity of the…

  4. Multivariate generalized hidden Markov regression models with random covariates: Physical exercise in an elderly population.

    PubMed

    Punzo, Antonio; Ingrassia, Salvatore; Maruotti, Antonello

    2018-04-22

    A time-varying latent variable model is proposed to jointly analyze multivariate mixed-support longitudinal data. The proposal can be viewed as an extension of hidden Markov regression models with fixed covariates (HMRMFCs), which is the state of the art for modelling longitudinal data, with a special focus on the underlying clustering structure. HMRMFCs are inadequate for applications in which a clustering structure can be identified in the distribution of the covariates, as the clustering is independent from the covariates distribution. Here, hidden Markov regression models with random covariates are introduced by explicitly specifying state-specific distributions for the covariates, with the aim of improving the recovering of the clusters in the data with respect to a fixed covariates paradigm. The hidden Markov regression models with random covariates class is defined focusing on the exponential family, in a generalized linear model framework. Model identifiability conditions are sketched, an expectation-maximization algorithm is outlined for parameter estimation, and various implementation and operational issues are discussed. Properties of the estimators of the regression coefficients, as well as of the hidden path parameters, are evaluated through simulation experiments and compared with those of HMRMFCs. The method is applied to physical activity data. Copyright © 2018 John Wiley & Sons, Ltd.

  5. Life satisfaction and bone mineral density among postmenopausal women: cross-sectional and longitudinal associations.

    PubMed

    Rauma, Päivi H; Koivumaa-Honkanen, Heli; Williams, Lana J; Tuppurainen, Marjo T; Kröger, Heikki P; Honkanen, Risto J

    2014-01-01

    The purpose of this study was to determine whether and how global life satisfaction is associated with bone mineral density (BMD) and bone loss. A total of 2167 women from a cohort of Finnish women born in 1932 to 1941 were included in the cross-sectional and 1147 women in the 10-year longitudinal part of the present study. Participants responded to a postal enquiry and underwent femoral BMD densitometry in 1999 (baseline) and 2009 (follow-up). During the follow-up, their life satisfaction was repeatedly measured using a four-item scale. Self-reported data on health, life-style, and medication were used to adjust the multivariate linear regression models. Mean (standard deviation) femoral BMD decreased over the 10-year follow-up from 880 (125) to 846 (122) mg/cm. In the multivariate model, life satisfaction (p = .028) and its improvement (p = .001) predicted reduced bone loss, whereas hospitalization due to depression predicted increased bone loss (B = -0.523 annual % change, standard error = 0.212, p = .014). These effects were independent of each other. Easily assessed global life satisfaction should be taken into account when effects of aging and prevention of osteoporosis as well as health promotion in postmenopausal women are considered.

  6. Analysis of longitudinal multivariate outcome data from couples cohort studies: application to HPV transmission dynamics

    PubMed Central

    Kong, Xiangrong; Wang, Mei-Cheng; Gray, Ronald

    2014-01-01

    We consider a specific situation of correlated data where multiple outcomes are repeatedly measured on each member of a couple. Such multivariate longitudinal data from couples may exhibit multi-faceted correlations which can be further complicated if there are polygamous partnerships. An example is data from cohort studies on human papillomavirus (HPV) transmission dynamics in heterosexual couples. HPV is a common sexually transmitted disease with 14 known oncogenic types causing anogenital cancers. The binary outcomes on the multiple types measured in couples over time may introduce inter-type, intra-couple, and temporal correlations. Simple analysis using generalized estimating equations or random effects models lacks interpretability and cannot fully utilize the available information. We developed a hybrid modeling strategy using Markov transition models together with pairwise composite likelihood for analyzing such data. The method can be used to identify risk factors associated with HPV transmission and persistence, estimate difference in risks between male-to-female and female-to-male HPV transmission, compare type-specific transmission risks within couples, and characterize the inter-type and intra-couple associations. Applying the method to HPV couple data collected in a Ugandan male circumcision (MC) trial, we assessed the effect of MC and the role of gender on risks of HPV transmission and persistence. PMID:26195849

  7. Differential and Long-Term Language Impact on Math

    ERIC Educational Resources Information Center

    Chen, Fang; Chalhoub-Deville, Micheline

    2016-01-01

    Literature provides consistent evidence that there is a strong relationship between language proficiency and math achievement. However, research results show conflicts supporting either an increasing or a decreasing longitudinal relationship between the two. This study explored a longitudinal data and adopted quantile regression analyses to…

  8. mvMapper: statistical and geographical data exploration and visualization of multivariate analysis of population structure

    USDA-ARS?s Scientific Manuscript database

    Characterizing population genetic structure across geographic space is a fundamental challenge in population genetics. Multivariate statistical analyses are powerful tools for summarizing genetic variability, but geographic information and accompanying metadata is not always easily integrated into t...

  9. The Relationship Between Job Satisfaction and Productivity-Related Costs: A Longitudinal Analysis.

    PubMed

    Arnold, Amélie E; Coffeng, Jennifer K; Boot, Cécile R L; van der Beek, Allard J; van Tulder, Maurits W; Nieboer, Dagmar; van Dongen, Johanna M

    2016-09-01

    The aim of this study was to examine the longitudinal relationship between job satisfaction and total productivity-related costs, and between job satisfaction and absenteeism and presenteeism costs separately. A secondary aim was to explore whether these relationships differed across job types. Linear generalized estimating equation analyses were used to explore the longitudinal relationships. To explore whether the relationships differed across job types, stratified analyses were performed. A significant relationship was found between job satisfaction and total productivity-related costs [β = &OV0556;-273; 95% confidence interval (95% CI): -407 to -200] and between job satisfaction and presenteeism costs (β = &OV0556;-276; 95% CI: -367 to -235), but not between job satisfaction and absenteeism costs. These relationships differed across job types. Higher levels of job satisfaction were longitudinally related to lower total productivity-related costs and presenteeism costs, but not to lower absenteeism costs. These relationships seem to differ across job types.

  10. Longitudinal long-period dynamics of aerospace craft

    NASA Technical Reports Server (NTRS)

    Berry, Donald T.

    1988-01-01

    Linear analyses are performed to examine the generic aspects of aerospace vehicle longitudinal long-period or trajectory modes of motion. The influence of Mach number, dynamic pressure, thrust-to-drag ratio, and propulsion system thrust laws on the longitudinal trajectory modes is presented in terms of phugoid frequency and damping and height mode stability. The results of these analyses are compared to flying qualities requirements where possible, and potential deficiencies in both the vehicle and the criteria are noted. A preliminary look at possible augmentation schemes to improve potential deficiencies is also presented. Interpretation of the practical consequences of the results is aided by typical time histories. Results indicate that propulsion system characteristics are the dominant influence on the longitudinal long-period flight dynamics of hypersonic aerospace craft. However, straightforward augmentation systems demonstrated the potential to accommodate these influences if the effects are included in the design process. These efforts may be hampered by a lack of design criteria for hypersonic aircraft.

  11. Multivariate analysis of prognostic factors for idiopathic sudden sensorineural hearing loss treated with adjuvant hyperbaric oxygen therapy.

    PubMed

    Xie, Shaobing; Qiang, Qingfen; Mei, Lingyun; He, Chufeng; Feng, Yong; Sun, Hong; Wu, Xuewen

    2018-01-01

    The objective of this study is to evaluate possible prognostic factors of idiopathic sudden sensorineural hearing loss (ISSNHL) treated with adjuvant hyperbaric oxygen therapy (HBOT) using univariate and multivariate analyses. From January 2008 to October 2016, records of 178 ISSNHL patients treated with auxiliary hyperbaric oxygen therapy were reviewed to assess hearing recovery and evaluate associated prognostic factors (gender, age, localization, initial hearing threshold, presence of tinnitus, vertigo, ear fullness, hypertension, diabetes, onset of HBOT, number of HBOT, and audiogram), by using univariate and multivariate analyses. The overall recovery rate was 37.1%, including complete recovery (19.7%) and partial recovery (17.4%). According to multivariate analysis, later onset of HBOT and higher initial hearing threshold were associated with a poor prognosis in ISSNHL patients treated with HBOT. HBOT is a safe and beneficial adjuvant therapy for ISSNHL patients. 20 sessions of HBOT is possibly enough to show its therapeutic effect. Earlier HBOT onset and lower initial hearing threshold is associated with favorable hearing recovery.

  12. Genetic Overlap Between Schizophrenia and Developmental Psychopathology: Longitudinal and Multivariate Polygenic Risk Prediction of Common Psychiatric Traits During Development.

    PubMed

    Nivard, Michel G; Gage, Suzanne H; Hottenga, Jouke J; van Beijsterveldt, Catharina E M; Abdellaoui, Abdel; Bartels, Meike; Baselmans, Bart M L; Ligthart, Lannie; Pourcain, Beate St; Boomsma, Dorret I; Munafò, Marcus R; Middeldorp, Christel M

    2017-10-21

    Several nonpsychotic psychiatric disorders in childhood and adolescence can precede the onset of schizophrenia, but the etiology of this relationship remains unclear. We investigated to what extent the association between schizophrenia and psychiatric disorders in childhood is explained by correlated genetic risk factors. Polygenic risk scores (PRS), reflecting an individual's genetic risk for schizophrenia, were constructed for 2588 children from the Netherlands Twin Register (NTR) and 6127 from the Avon Longitudinal Study of Parents And Children (ALSPAC). The associations between schizophrenia PRS and measures of anxiety, depression, attention deficit hyperactivity disorder (ADHD), and oppositional defiant disorder/conduct disorder (ODD/CD) were estimated at age 7, 10, 12/13, and 15 years in the 2 cohorts. Results were then meta-analyzed, and a meta-regression analysis was performed to test differences in effects sizes over, age and disorders. Schizophrenia PRS were associated with childhood and adolescent psychopathology. Meta-regression analysis showed differences in the associations over disorders, with the strongest association with childhood and adolescent depression and a weaker association for ODD/CD at age 7. The associations increased with age and this increase was steepest for ADHD and ODD/CD. Genetic correlations varied between 0.10 and 0.25. By optimally using longitudinal data across diagnoses in a multivariate meta-analysis this study sheds light on the development of childhood disorders into severe adult psychiatric disorders. The results are consistent with a common genetic etiology of schizophrenia and developmental psychopathology as well as with a stronger shared genetic etiology between schizophrenia and adolescent onset psychopathology. © The Author 2017. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com

  13. Longitudinal change instead of baseline testosterone predicts depressive symptoms.

    PubMed

    Kische, Hanna; Pieper, Lars; Venz, John; Klotsche, Jens; März, Winfried; Koch-Gromus, Uwe; Pittrow, David; Lehnert, Hendrik; Silber, Sigmund; Stalla, G K; Zeiher, Andreas M; Wittchen, Hans-Ulrich; Haring, Robin

    2018-03-01

    The association between total testosterone (T) and depression mostly relies on single sex hormone assessment and remains inconclusive. Thus, we investigated the comparative predictive performance of baseline T and change in T with development of depressive symptoms and incident depressive episodes. We used data from 6493 primary care patients (2653 men and 3840 women) of the DETECT study (Diabetes Cardiovascular Risk-Evaluation: Targets and Essential Data for Commitment of Treatment), including four-year follow-up, repeated immunoassay-based measurement of serum T and depressive symptoms assessed by the Depression Screening Questionnaire (DSQ). Cross-sectional and longitudinal associations of baseline T and one-year change in T with prevalent and incident depression were investigated using age- and multivariable-adjusted regression models. Baseline T showed no association with prevalent or incident depressive symptoms and episodes in both sexes. In men, a positive change in T (higher T at one-year follow-up compared to baseline) was associated with a lower burden of depressive symptoms (β-coefficient per unit change in T: -0.17; 95% CI: -0.31 to -0.04) and lower risk of incident depressive symptoms (odds ratio per unit change in T: 0.84; 95% CI: 0.72-0.98) at four-year follow-up. In women, the association of T change with incident depressive episodes was rendered non-significant after multivariable adjustment. The present study observed a sex-specific inverse association of T change, but not baseline T, with increased depressive symptom burden in men. Future studies should assess longitudinal changes in sex hormone status as predictor of adverse health outcomes related to low T. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Sexual, marital, and general life functioning in couples coping with colorectal cancer: a dyadic study across time.

    PubMed

    Traa, Marjan J; Braeken, Johan; De Vries, Jolanda; Roukema, Jan A; Slooter, Gerrit D; Crolla, Rogier M P H; Borremans, Monique P M; Den Oudsten, Brenda L

    2015-09-01

    This study evaluated the following: (a) levels of sexual, marital, and general life functioning for both patients and partners; (b) interdependence between both members of the couple; and (c) longitudinal change in sexual, marital, and general life functioning and longitudinal stress-spillover effects in these three domains from a dyadic perspective. Couples (n = 102) completed the Maudsley Marital Questionnaire preoperatively and 3 and 6 months postoperatively. Mean scores were compared with norm scores. A multivariate general linear model and a multivariate latent difference score - structural equation modeling (LDS-SEM), which took into account actor and partner effects, were evaluated. Patients and partners reported lower sexual, mostly similar marital, and higher general life functioning compared with norm scores. Moderate to high within-dyad associations were found. The LDS-SEM model mostly showed actor effects. Yet the longitudinal change in the partners' sexual functioning was determined not only by their own preoperative sexual functioning but also by that of the patient. Preoperative sexual functioning did not spill over to the other two domains for patients and partners, whereas the patients' preoperative general life functioning influenced postoperative change in marital and sexual functioning. Health care professionals should examine potential sexual problems but have to be aware that these problems may not spill over to the marital and general life domains. In contrast, low functioning in the general life domain may spill over to the marital and sexual domains. The interdependence between patients and partners implies that a couple-based perspective (e.g., couple-based interventions/therapies) to coping with cancer is needed. Copyright © 2015 John Wiley & Sons, Ltd.

  15. Multivariate quantum memory as controllable delayed multi-port beamsplitter

    NASA Astrophysics Data System (ADS)

    Vetlugin, A. N.; Sokolov, I. V.

    2016-03-01

    The addressability of parallel spatially multimode quantum memory for light allows one to control independent collective spin waves within the same cold atomic ensemble. Generally speaking, there are transverse and longitudinal degrees of freedom of the memory that one can address by a proper choice of the pump (control) field spatial pattern. Here we concentrate on the mutual evolution and transformation of quantum states of the longitudinal modes of collective spin coherence in the cavity-based memory scheme. We assume that these modes are coherently controlled by the pump waves of the on-demand transverse profile, that is, by the superpositions of waves propagating in the directions close to orthogonal to the cavity axis. By the write-in, this allows one to couple a time sequence of the incoming quantized signals to a given set of superpositions of orthogonal spin waves. By the readout, one can retrieve quantum states of the collective spin waves that are controllable superpositions of the initial ones and are coupled on demand to the output signal sequence. In a general case, the memory is able to operate as a controllable delayed multi-port beamsplitter, capable of transformation of the delays, the durations and time shapes of signals in the sequence. We elaborate the theory of such light-matter interface for the spatially multivariate cavity-based off-resonant Raman-type quantum memory. Since, in order to speed up the manipulation of complex signals in multivariate memories, it might be of interest to store relatively short light pulses of a given time shape, we also address some issues of the cavity-based memory operation beyond the bad cavity limit.

  16. Longitudinal analyses of the DNA methylome in deployed military servicemen identify susceptibility loci for post-traumatic stress disorder.

    PubMed

    Rutten, B P F; Vermetten, E; Vinkers, C H; Ursini, G; Daskalakis, N P; Pishva, E; de Nijs, L; Houtepen, L C; Eijssen, L; Jaffe, A E; Kenis, G; Viechtbauer, W; van den Hove, D; Schraut, K G; Lesch, K-P; Kleinman, J E; Hyde, T M; Weinberger, D R; Schalkwyk, L; Lunnon, K; Mill, J; Cohen, H; Yehuda, R; Baker, D G; Maihofer, A X; Nievergelt, C M; Geuze, E; Boks, M P M

    2018-05-01

    In order to determine the impact of the epigenetic response to traumatic stress on post-traumatic stress disorder (PTSD), this study examined longitudinal changes of genome-wide blood DNA methylation profiles in relation to the development of PTSD symptoms in two prospective military cohorts (one discovery and one replication data set). In the first cohort consisting of male Dutch military servicemen (n=93), the emergence of PTSD symptoms over a deployment period to a combat zone was significantly associated with alterations in DNA methylation levels at 17 genomic positions and 12 genomic regions. Evidence for mediation of the relation between combat trauma and PTSD symptoms by longitudinal changes in DNA methylation was observed at several positions and regions. Bioinformatic analyses of the reported associations identified significant enrichment in several pathways relevant for symptoms of PTSD. Targeted analyses of the significant findings from the discovery sample in an independent prospective cohort of male US marines (n=98) replicated the observed relation between decreases in DNA methylation levels and PTSD symptoms at genomic regions in ZFP57, RNF39 and HIST1H2APS2. Together, our study pinpoints three novel genomic regions where longitudinal decreases in DNA methylation across the period of exposure to combat trauma marks susceptibility for PTSD.

  17. Longitudinal association of hemostatic factors with risk for cancers of the breast, colorectum, and lung among postmenopausal women.

    PubMed

    Kabat, Geoffrey C; Salazar, Christian R; Zaslavsky, Oleg; Lane, Dorothy S; Rohan, Thomas E

    2016-09-01

    The aim of this study was to examine whether hemostatic factors associated with coagulation and inflammation pathways are associated with cancer risk in postmenopausal women. We used data from the Women's Health Initiative study to examine the association of plasma fibrinogen levels, factor VII antigen activity, and factor VII concentration measured at baseline and during follow-up with the risk for cancers of the breast, colorectum, and lung. Among 5287 women who were followed up for a median of 11.4 years, 275 cases of breast cancer, 102 cases of colorectal cancer, and 90 cases of lung cancer were identified. Cox proportional hazards models were used to estimate hazard ratios and 95% confidence intervals for the association of hemostatic factors with each cancer. Hemostatic factors were not associated with breast cancer in either baseline or longitudinal analyses. Baseline hemostatic factors showed weak associations with colorectal cancer; however, no association was seen in longitudinal analyses. Fibrinogen was positively associated with lung cancer in both baseline and longitudinal analyses; the association was seen only in never and former smokers, not in current smokers. We found no evidence of an association between hemostatic factors and breast or colorectal cancer in postmenopausal women. The positive association of fibrinogen levels with lung cancer requires confirmation in larger studies.

  18. Linkage Analysis of a Model Quantitative Trait in Humans: Finger Ridge Count Shows Significant Multivariate Linkage to 5q14.1

    PubMed Central

    Medland, Sarah E; Loesch, Danuta Z; Mdzewski, Bogdan; Zhu, Gu; Montgomery, Grant W; Martin, Nicholas G

    2007-01-01

    The finger ridge count (a measure of pattern size) is one of the most heritable complex traits studied in humans and has been considered a model human polygenic trait in quantitative genetic analysis. Here, we report the results of the first genome-wide linkage scan for finger ridge count in a sample of 2,114 offspring from 922 nuclear families. Both univariate linkage to the absolute ridge count (a sum of all the ridge counts on all ten fingers), and multivariate linkage analyses of the counts on individual fingers, were conducted. The multivariate analyses yielded significant linkage to 5q14.1 (Logarithm of odds [LOD] = 3.34, pointwise-empirical p-value = 0.00025) that was predominantly driven by linkage to the ring, index, and middle fingers. The strongest univariate linkage was to 1q42.2 (LOD = 2.04, point-wise p-value = 0.002, genome-wide p-value = 0.29). In summary, the combination of univariate and multivariate results was more informative than simple univariate analyses alone. Patterns of quantitative trait loci factor loadings consistent with developmental fields were observed, and the simple pleiotropic model underlying the absolute ridge count was not sufficient to characterize the interrelationships between the ridge counts of individual fingers. PMID:17907812

  19. Euclidean distance and Kolmogorov-Smirnov analyses of multi-day auditory event-related potentials: a longitudinal stability study

    NASA Astrophysics Data System (ADS)

    Durato, M. V.; Albano, A. M.; Rapp, P. E.; Nawang, S. A.

    2015-06-01

    The validity of ERPs as indices of stable neurophysiological traits is partially dependent on their stability over time. Previous studies on ERP stability, however, have reported diverse stability estimates despite using the same component scoring methods. This present study explores a novel approach in investigating the longitudinal stability of average ERPs—that is, by treating the ERP waveform as a time series and then applying Euclidean Distance and Kolmogorov-Smirnov analyses to evaluate the similarity or dissimilarity between the ERP time series of different sessions or run pairs. Nonlinear dynamical analysis show that in the absence of a change in medical condition, the average ERPs of healthy human adults are highly longitudinally stable—as evaluated by both the Euclidean distance and the Kolmogorov-Smirnov test.

  20. Mode of Delivery and Long-Term Health-Related Quality-of-Life Outcomes: A Prospective Population-Based Study.

    PubMed

    Petrou, Stavros; Kim, Sung Wook; McParland, Penny; Boyle, Elaine M

    2017-06-01

    Relatively little is known about the effects of mode of delivery on long-term health-related quality-of-life outcomes. Furthermore, no previous study has expressed these outcomes in preference-based (utility) metrics. The study population comprised 2,161 mothers recruited from a prospective population-based study in the East Midlands of England encompassing live births and stillbirths between 32 +0 and 36 +6 weeks' gestation and a sample of term-born controls. Perinatal data were extracted from the mothers' maternity records. Health-related quality-of-life outcomes were assessed at 12 months postpartum, using the EuroQol Five Dimensions (EQ-5D) measure with responses to the EQ-5D descriptive system converted into health utility scores. Descriptive statistics and multivariable analyses were used to estimate the relationship between the mode of delivery and health-related quality-of-life outcomes. The overall health-related quality-of-life profile of the women in the study cohort mirrored that of the English adult population as revealed by national health surveys. A significantly higher proportion of women delivering by cesarean delivery reported some, moderate, severe, or extreme pain or discomfort at 12 months postpartum than women undergoing spontaneous vaginal delivery. Multivariable analyses, using the Ordinary Least Squares estimator revealed that, after controlling for maternal sociodemographic characteristics, cesarean delivery without maternal or fetal compromise was associated with a significant EQ-5D utility decrement in comparison to spontaneous vaginal delivery among all women (-0.026; p = 0.038) and among mothers of term-born infants (-0.062; p < 0.001). Among mothers of term-born infants, this result was replicated in models that controlled for all maternal and infant characteristics (utility decrement of -0.061; p < 0.001). The results were confirmed by sensitivity analyses that varied the categorization of the main exposure variable (mode of delivery) and the econometric strategy. Among mothers of term-born infants, cesarean delivery without maternal or fetal compromise is associated with poorer long-term health-related quality of life in comparison to spontaneous vaginal delivery. Further longitudinal studies are needed to understand the magnitude, trajectory, and underpinning mechanisms of health-related quality-of-life outcomes following different modes of delivery. © 2016 Wiley Periodicals, Inc.

  1. LIFESPAN: A tool for the computer-aided design of longitudinal studies

    PubMed Central

    Brandmaier, Andreas M.; von Oertzen, Timo; Ghisletta, Paolo; Hertzog, Christopher; Lindenberger, Ulman

    2015-01-01

    Researchers planning a longitudinal study typically search, more or less informally, a multivariate space of possible study designs that include dimensions such as the hypothesized true variance in change, indicator reliability, the number and spacing of measurement occasions, total study time, and sample size. The main search goal is to select a research design that best addresses the guiding questions and hypotheses of the planned study while heeding applicable external conditions and constraints, including time, money, feasibility, and ethical considerations. Because longitudinal study selection ultimately requires optimization under constraints, it is amenable to the general operating principles of optimization in computer-aided design. Based on power equivalence theory (MacCallum et al., 2010; von Oertzen, 2010), we propose a computational framework to promote more systematic searches within the study design space. Starting with an initial design, the proposed framework generates a set of alternative models with equal statistical power to detect hypothesized effects, and delineates trade-off relations among relevant parameters, such as total study time and the number of measurement occasions. We present LIFESPAN (Longitudinal Interactive Front End Study Planner), which implements this framework. LIFESPAN boosts the efficiency, breadth, and precision of the search for optimal longitudinal designs. Its initial version, which is freely available at http://www.brandmaier.de/lifespan, is geared toward the power to detect variance in change as specified in a linear latent growth curve model. PMID:25852596

  2. Problem Behaviours, Traditional Bullying and Cyberbullying among Adolescents: Longitudinal Analyses

    ERIC Educational Resources Information Center

    Lester, Leanne; Cross, Donna; Shaw, Therese

    2012-01-01

    Problem Behaviour Theory suggests that young people's problem behaviours tend to cluster. This study examined the relationship between traditional bullying, cyberbullying and engagement in problem behaviours using longitudinal data from approximately 1500 students. Levels of traditional victimisation and perpetration at the beginning of secondary…

  3. Patterns and Predictors of Language and Literacy Abilities 4-10 Years in the Longitudinal Study of Australian Children

    PubMed Central

    Zubrick, Stephen R.; Taylor, Catherine L.; Christensen, Daniel

    2015-01-01

    Aims Oral language is the foundation of literacy. Naturally, policies and practices to promote children’s literacy begin in early childhood and have a strong focus on developing children’s oral language, especially for children with known risk factors for low language ability. The underlying assumption is that children’s progress along the oral to literate continuum is stable and predictable, such that low language ability foretells low literacy ability. This study investigated patterns and predictors of children’s oral language and literacy abilities at 4, 6, 8 and 10 years. The study sample comprised 2,316 to 2,792 children from the first nationally representative Longitudinal Study of Australian Children (LSAC). Six developmental patterns were observed, a stable middle-high pattern, a stable low pattern, an improving pattern, a declining pattern, a fluctuating low pattern, and a fluctuating middle-high pattern. Most children (69%) fit a stable middle-high pattern. By contrast, less than 1% of children fit a stable low pattern. These results challenged the view that children’s progress along the oral to literate continuum is stable and predictable. Findings Multivariate logistic regression was used to investigate risks for low literacy ability at 10 years and sensitivity-specificity analysis was used to examine the predictive utility of the multivariate model. Predictors were modelled as risk variables with the lowest level of risk as the reference category. In the multivariate model, substantial risks for low literacy ability at 10 years, in order of descending magnitude, were: low school readiness, Aboriginal and/or Torres Strait Islander status and low language ability at 8 years. Moderate risks were high temperamental reactivity, low language ability at 4 years, and low language ability at 6 years. The following risk factors were not statistically significant in the multivariate model: Low maternal consistency, low family income, health care card, child not read to at home, maternal smoking, maternal education, family structure, temperamental persistence, and socio-economic area disadvantage. The results of the sensitivity-specificity analysis showed that a well-fitted multivariate model featuring risks of substantive magnitude did not do particularly well in predicting low literacy ability at 10 years. PMID:26352436

  4. Vehicle longitudinal velocity estimation during the braking process using unknown input Kalman filter

    NASA Astrophysics Data System (ADS)

    Moaveni, Bijan; Khosravi Roqaye Abad, Mahdi; Nasiri, Sayyad

    2015-10-01

    In this paper, vehicle longitudinal velocity during the braking process is estimated by measuring the wheels speed. Here, a new algorithm based on the unknown input Kalman filter is developed to estimate the vehicle longitudinal velocity with a minimum mean square error and without using the value of braking torque in the estimation procedure. The stability and convergence of the filter are analysed and proved. Effectiveness of the method is shown by designing a real experiment and comparing the estimation result with actual longitudinal velocity computing from a three-axis accelerometer output.

  5. Microcracking, microcrack-induced delamination, and longitudinal splitting of advanced composite structures

    NASA Technical Reports Server (NTRS)

    Nairn, John A.

    1992-01-01

    A combined analytical and experimental study was conducted to analyze microcracking, microcrack-induced delamination, and longitudinal splitting in polymer matrix composites. Strain energy release rates, calculated by a variational analysis, were used in a failure criterion to predict microcracking. Predictions and test results were compared for static, fatigue, and cyclic thermal loading. The longitudinal splitting analysis accounted for the effects of fiber bridging. Test data are analyzed and compared for longitudinal splitting and delamination under mixed-mode loading. This study emphasizes the importance of using fracture mechanics analyses to understand the complex failure processes that govern composite strength and life.

  6. Factors associated with repeated refusal to participate in longitudinal population-based HIV surveillance in rural South Africa: an observational study, regression analyses

    PubMed Central

    Giordano, Katie; McGrath, Nuala; Snow, Rachel; Harlow, Siobán; Newell, Marie-Louise

    2014-01-01

    Background For many estimation purposes, individuals who repeatedly refuse to participate in longitudinal HIV surveillance pose a bigger threat to valid inferences than individuals who participate at least occasionally. We investigate the determinants of repeated refusal to consent to HIV testing in a population-based longitudinal surveillance in rural South Africa. Methods We used data from two years (2005 & 2006) of the annual HIV surveillance conducted by the Africa Centre for Health and Population Studies, linking the HIV surveillance data to demographic and socioeconomic data. The outcome for the analysis was “repeated refusal”. Demographic variables included sex, age, highest educational attainment, and place of residence. We also included a measure of wealth and the variable “ever had sex”. To compare the association of each variable with the outcome, unadjusted odds ratios and standard errors were estimated. Multivariable logistic regression was used to estimate adjusted odds ratios and their standard errors. Data were analyzed using STATA 10.0. Results Of 15,557 eligible individuals, 46% refused to test for HIV in both rounds. Males were significantly more likely than females to repeatedly refuse testing. Holding all other variables constant, individuals in the middle age groups were more likely to repeatedly refuse testing compared with younger and older age groups. The odds of repeated refusal increased with increasing level of education and relative wealth. People living in urban areas were significantly more likely to repeatedly refuse an HIV test than people living in peri-urban or rural areas. Compared to those who had ever had sex, both males and females who had not yet had sex were significantly more likely to refuse to participate. Conclusions The likelihood of repeated refusal to test for HIV in this longitudinal surveillance increases with education, wealth, urbanization, and primary sexual abstinence. Since the factors determining repeated HIV testing refusal are likely associated with HIV status, it is critical that selection effects are controlled for in the analysis of HIV surveillance data. Interventions to increase consent to HIV testing should consider targeting the relatively well educated and wealthy, people in urban areas, and individuals who have not yet sexually debuted. PMID:25621095

  7. Recent im/migration to Canada linked to unmet health needs among sex workers in Vancouver, Canada: Findings of a longitudinal study.

    PubMed

    Sou, Julie; Goldenberg, Shira M; Duff, Putu; Nguyen, Paul; Shoveller, Jean; Shannon, Kate

    2017-05-01

    Despite universal health care in Canada, sex workers (SWs) and im/migrants experience suboptimal health care access. In this analysis, we examined the correlates of unmet health needs among SWs in Metro Vancouver over time. Data from a longitudinal cohort of women SWs (An Evaluation of Sex Workers Health Access [AESHA]) were used. Of 742 SWs, 25.5% reported unmet health needs at least once over the 4-year study period. In multivariable logistic regression using generalized estimating equations, recent im/migration had the strongest impact on unmet health needs; long-term im/migration, policing, and trauma were also important determinants. Legal and social supports to promote im/migrant SWs' access to health care are recommended.

  8. Longitudinal trajectories of self-system processes and depressive symptoms among maltreated and nonmaltreated children

    PubMed Central

    Kim, Jungmeen; Cicchetti, Dante

    2006-01-01

    This study used latent growth modeling to investigate longitudinal relationships between self-system processes and depressive symptoms among maltreated (n=142) and nonmaltreated children (n=109) aged 6–11 years. On average, self-esteem and self-agency increased and depressive symptoms decreased over time. Multivariate growth modeling indicated that, regardless of gender, physical abuse was negatively related to initial levels of self-esteem, and physical abuse and physical neglect were positively associated with initial levels of depressive symptoms. Emotional maltreatment was predictive of changes in self-esteem and changes in depressive symptoms. Initial levels of self-esteem were negatively associated with initial levels of depressive symptoms. The findings contribute to enhancing our understanding of the developmental processes whereby early maltreatment experiences are linked to later maladjustment. PMID:16686792

  9. Reconfigurable multivariable control law for commercial airplane using a direct digital output feedback design

    NASA Technical Reports Server (NTRS)

    Ostroff, A. J.; Hueschen, R. M.

    1984-01-01

    The ability of a pilot to reconfigure the control surfaces on an airplane after a failure, allowing the airplane to recover to a safe condition for landing, becomes more difficult with increasing airplane complexity. Techniques are needed to stabilize and control the airplane immediately after a failure, allowing the pilot time to make longer range decisions. This paper shows a design of a discrete multivariable control law using four controls for the longitudinal channel of a B-737. Single control element failures are allowed in three of the four controls. The four controls design and failure cases are analyzed by means of a digital airplane simulation, with regard to tracking capability and ability to overcome severe windshear and turbulence during the aproach and landing phase of flight.

  10. Lumbar Muscle Cross-Sectional Areas Do Not Predict Clinical Outcomes in Adults With Spinal Stenosis: A Longitudinal Study.

    PubMed

    Gellhorn, Alfred C; Suri, Pradeep; Rundell, Sean D; Olafsen, Nathan; Carlson, M Jake; Johnson, Steve; Fry, Adrielle; Annaswamy, Thiru M; Gilligan, Christopher; Comstock, Bryan; Heagerty, Patrick; Friedly, Janna; Jarvik, Jeffrey G

    2017-06-01

    Minimal longitudinal data exist regarding the role of lumbar musculature in predicting back pain and function. In cross-sectional study designs, there is often atrophy of the segmental multifidus muscle in subjects with low back pain compared with matched controls. However, the cross-sectional design of these studies prevents drawing conclusions regarding whether lumbar muscle characteristics predict or modify future back pain or function. The primary objective of this study is to determine whether the cross-sectional area (CSA) of lumbar muscles predict functional status or back pain at 6- or 12-month follow-up in older adults with spinal degeneration. The secondary objective is to evaluate whether these muscle characteristics improve outcome prediction above and beyond the prognostic information conferred by demographic and psychosocial variables. Secondary analysis of a randomized controlled trial. A total of 209 adults aged 50 years and older with clinical and radiographic spinal stenosis from the Lumbar Epidural steroid injection for Spinal Stenosis (LESS) trial. Using baseline magnetic resonance images, we calculated CSAs of the lumbar multifidus, psoas, and quadratus lumborum muscles using a standardized protocol by manually tracing the borders of each of the muscles. The relationship between lumbar muscle CSAs and baseline measures was assessed with Pearson or Spearman correlation coefficients. The relationship between lumbar muscle characteristics and 6- and 12-month Roland Morris Disability Questionnaire (RDQ) and back pain Numeric Rating Scale (NRS) responses was further evaluated with multivariate linear regression. A hierarchical approach to the regression was performed: a basic model with factors of conceptual importance including age, gender, BMI, and baseline RDQ score formed the first step. The second and third steps evaluated whether psychosocial variables or muscle measures conferred additional prognostic information to the basic model. Function as measured by the RDQ and back pain as measured by the NRS at 6- and 12-month follow-up. Lumbar muscle CSA was not a significant predictor of 6- or 12-month RDQ or pain score in multivariate analyses. Cross-sectional areas of lumbar muscles do not predict function or pain at medium- and long-term follow-up in adults with lumbar spinal stenosis. III. Copyright © 2017 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  11. Early Cognitive Profiles of Emergent Readers: A Longitudinal Study

    ERIC Educational Resources Information Center

    Brunswick, Nicola; Martin, G. Neil; Rippon, Georgina

    2012-01-01

    This longitudinal study examined the contribution of phonological awareness, phonological memory, and visuospatial ability to reading development in 142 English-speaking children from the start of kindergarten to the middle of Grade 2. Partial cross-lagged analyses revealed significant relationships between early performance on block design and…

  12. Conducting Three-Level Longitudinal Analyses

    ERIC Educational Resources Information Center

    Peugh, James L.; Heck, Ronald H.

    2017-01-01

    Researchers in the field of early adolescence interested in quantifying the environmental influences on a response variable of interest over time would use cluster sampling (i.e., obtaining repeated measures from students nested within classrooms and/or schools) to obtain the needed sample size. The resulting longitudinal data would be nested at…

  13. Family Racial Socialization and Ecological Competence: Longitudinal Assessments of African-American Transracial Adoptees.

    ERIC Educational Resources Information Center

    DeBerry, Kimberly M.; And Others

    1996-01-01

    Examined family racial socialization and ecological competence during childhood and adolescence in a sample of 88 African-American transracial adoptees and their families. Longitudinal path analyses indicated that Eurocentric reference group orientation (RGO) increased over time while Africentric RGO declined for the adoptees, and maladjustment…

  14. The Merits of Using Longitudinal Mediation

    ERIC Educational Resources Information Center

    Jose, Paul E.

    2016-01-01

    Many of the mediation analyses reported in the literature are based on concurrent or single-occasion data sets. The 2 overarching themes of the present article are: Results of concurrent mediations are inherently ambiguous, and researchers would be wise to conduct mediations on longitudinal data sets instead. An example included here demonstrates…

  15. Commentary: Mediation Analysis, Causal Process, and Cross-Sectional Data

    ERIC Educational Resources Information Center

    Shrout, Patrick E.

    2011-01-01

    Maxwell, Cole, and Mitchell (2011) extended the work of Maxwell and Cole (2007), which raised important questions about whether mediation analyses based on cross-sectional data can shed light on longitudinal mediation process. The latest article considers longitudinal processes that can only be partially explained by an intervening variable, and…

  16. Associations between residential traffic noise exposure and smoking habits and alcohol consumption-A population-based study.

    PubMed

    Roswall, Nina; Christensen, Jeppe Schultz; Bidstrup, Pernille Envold; Raaschou-Nielsen, Ole; Jensen, Steen Solvang; Tjønneland, Anne; Sørensen, Mette

    2018-05-01

    Traffic noise stresses and disturbs sleep. It has been associated with various diseases, and has recently also been associated with lifestyle. Hence, the association between traffic noise and disease could partly operate via a pathway of lifestyle habits, including smoking and alcohol intake. We investigated associations between modelled residential traffic noise and smoking habits and alcohol consumption. In a cohort of 57,053 participants, we performed cross-sectional analyses using data from a baseline questionnaire (1993-97), and longitudinal analyses of change between baseline and follow-up (2000-02). Smoking status (never, former, current) and intensity (tobacco, g/day) and alcohol consumption (g/day) was self-reported at baseline and follow-up. Address history from 1987-2002 for all participants were found in national registries, and road traffic and railway noise was modelled 1 and 5 years before enrolment, and from baseline to follow-up. Analyses were performed using logistic and linear regression, and adjusted for demographics, socioeconomic variables, leisure-time sports, and noise from the opposite source (road/railway). Road traffic noise exposure 5 years before baseline was positively associated with alcohol consumption (adjusted difference per 10 dB: 1.38 g/day, 95% confidence interval (CI): 1.10-1.65), smoking intensity (adjusted difference per 10 dB: 0.40 g/day, 95% CI: 0.19-0.61), and odds for being a current vs. never/former smoker at baseline (odds ratio (OR): 1.14; 95% CI: 1.10-1.17). In longitudinal analyses, we found no association between road traffic noise and change in smoking and alcohol habits. Railway noise was not associated with smoking habits and alcohol consumption, neither in cross-sectional nor in longitudinal analyses. The study suggests that long-term exposure to residential road traffic is associated with smoking habits and alcohol consumption, albeit only in cross-sectional, but not in longitudinal analyses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. A Multivariate Genome-Wide Association Analysis of 10 LDL Subfractions, and Their Response to Statin Treatment, in 1868 Caucasians

    PubMed Central

    Shim, Heejung; Chasman, Daniel I.; Smith, Joshua D.; Mora, Samia; Ridker, Paul M.; Nickerson, Deborah A.; Krauss, Ronald M.; Stephens, Matthew

    2015-01-01

    We conducted a genome-wide association analysis of 7 subfractions of low density lipoproteins (LDLs) and 3 subfractions of intermediate density lipoproteins (IDLs) measured by gradient gel electrophoresis, and their response to statin treatment, in 1868 individuals of European ancestry from the Pharmacogenomics and Risk of Cardiovascular Disease study. Our analyses identified four previously-implicated loci (SORT1, APOE, LPA, and CETP) as containing variants that are very strongly associated with lipoprotein subfractions (log10Bayes Factor > 15). Subsequent conditional analyses suggest that three of these (APOE, LPA and CETP) likely harbor multiple independently associated SNPs. Further, while different variants typically showed different characteristic patterns of association with combinations of subfractions, the two SNPs in CETP show strikingly similar patterns - both in our original data and in a replication cohort - consistent with a common underlying molecular mechanism. Notably, the CETP variants are very strongly associated with LDL subfractions, despite showing no association with total LDLs in our study, illustrating the potential value of the more detailed phenotypic measurements. In contrast with these strong subfraction associations, genetic association analysis of subfraction response to statins showed much weaker signals (none exceeding log10Bayes Factor of 6). However, two SNPs (in APOE and LPA) previously-reported to be associated with LDL statin response do show some modest evidence for association in our data, and the subfraction response proles at the LPA SNP are consistent with the LPA association, with response likely being due primarily to resistance of Lp(a) particles to statin therapy. An additional important feature of our analysis is that, unlike most previous analyses of multiple related phenotypes, we analyzed the subfractions jointly, rather than one at a time. Comparisons of our multivariate analyses with standard univariate analyses demonstrate that multivariate analyses can substantially increase power to detect associations. Software implementing our multivariate analysis methods is available at http://stephenslab.uchicago.edu/software.html. PMID:25898129

  18. The Relationships between Perceived Parenting Style, Learning Motivation, Friendship Satisfaction, and the Addictive Use of Smartphones with Elementary School Students of South Korea: Using Multivariate Latent Growth Modeling

    ERIC Educational Resources Information Center

    Bae, Sung Man

    2015-01-01

    We examined how perceived parenting style, friendship satisfaction, and academic motivation influence the addictive use of smartphones longitudinally. We utilized the panel data (from 2010-2012) of Korean children and youth panel survey of the National Youth Policy Institute. Data were collected from 2,376 individuals in the first year (boys:…

  19. Prediction of coefficients of thermal expansion for unidirectional composites

    NASA Technical Reports Server (NTRS)

    Bowles, David E.; Tompkins, Stephen S.

    1989-01-01

    Several analyses for predicting the longitudinal, alpha(1), and transverse, alpha(2), coefficients of thermal expansion of unidirectional composites were compared with each other, and with experimental data on different graphite fiber reinforced resin, metal, and ceramic matrix composites. Analytical and numerical analyses that accurately accounted for Poisson restraining effects in the transverse direction were in consistently better agreement with experimental data for alpha(2), than the less rigorous analyses. All of the analyses predicted similar values of alpha(1), and were in good agreement with the experimental data. A sensitivity analysis was conducted to determine the relative influence of constituent properties on the predicted values of alpha(1), and alpha(2). As would be expected, the prediction of alpha(1) was most sensitive to longitudinal fiber properties and the prediction of alpha(2) was most sensitive to matrix properties.

  20. Multivariate evaluation of the effectiveness of treatment efficacy of cypermethrin against sea lice (Lepeophtheirus salmonis) in Atlantic salmon (Salmo salar)

    PubMed Central

    2013-01-01

    Background The sea louse Lepeophtheirus salmonis is the most important ectoparasite of farmed Atlantic salmon (Salmo salar) in Norwegian aquaculture. Control of sea lice is primarily dependent on the use of delousing chemotherapeutants, which are both expensive and toxic to other wildlife. The method most commonly used for monitoring treatment effectiveness relies on measuring the percentage reduction in the mobile stages of Lepeophtheirus salmonis only. However, this does not account for changes in the other sea lice stages and may result in misleading or incomplete interpretation regarding the effectiveness of treatment. With the aim of improving the evaluation of delousing treatments, we explored multivariate analyses of bath treatments using the topical pyrethroid, cypermethrin, in salmon pens at five Norwegian production sites. Results Conventional univariate analysis indicated reductions of over 90% in mobile stages at all sites. In contrast, multivariate analyses indicated differing treatment effectiveness between sites (p-value < 0.01) based on changes in the proportion and abundance of the chalimus and PAAM (pre-adult and adult males) stages. Low water temperatures and shortened intervals between sampling after treatment may account for the differences in the composition of chalimus and PAAM stage groups following treatment. Using multivariate analysis, such factors could be separated from those which were attributable to inadequate treatment or chemotherapeutant failure. Conclusions Multivariate analyses for evaluation of treatment effectiveness against multiple life cycle stages of L. salmonis yield additional information beyond that derivable from univariate methods. This can aid in the identification of causes of apparent treatment failure in salmon aquaculture. PMID:24354936

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