Construction of Wave IV dbGaP GWAS Sample Weight

This document provides a brief overview of the steps in constructing GWAS sample weights. It also reports results of some statistical analysis using the constructed weights. The total number of GWAS sample (N=9,975) who were actually assayed and number of those (N=12,234) who consented to be archived and assayed are different. When the proportions of subjects who have consented and who have actually been assayed are different for certain Add Health post-stratification domains, this might cause problems if we simply use grand sample weights for GWAS sample (Bethlehem 2002). We thus developed weights for this special sample

Early Sex Work Initiation and Violence against Female Sex Workers in Mombasa, Kenya

Between 20 and 40 % of female sex workers (FSWs) began sex work before age 18. Little is known concerning whether early initiation of sex work impacts later experiences in adulthood, including violence victimization. This paper examines the relationship between early initiation of sex work and violence victimization during adulthood. The sample included 816 FSWs in Mombasa, Kenya, recruited from HIV prevention drop-in centers who were 18 years or older and moderate-risk drinkers. Early initiation was defined as beginning sex work at 17 or younger. Logistic regression modeled recent violence as a function of early initiation, adjusting for drop-in center, age, education, HIV status, supporting others, and childhood abuse. Twenty percent of the sample reported early initiation of sex work. Although both early initiators and other FSWs reported commonly experiencing recent violence, early initiators were significantly more likely to experience recent physical and sexual violence and verbal abuse from paying partners. Early initiation was not associated with physical or sexual violence from non-paying partners. Many FSWs begin sex work before age 18. Effective interventions focused on preventing this are needed. In addition, interventions are needed to prevent violence against all FSWs, in particular, those who initiated sex work during childhood or adolescence

Early sex work initiation and condom use among alcohol-using female sex workers in Mombasa, Kenya: a cross-sectional analysis

Early initiation of sex work is prevalent among female sex workers (FSWs) worldwide. The objectives of this study were to investigate if early initiation of sex work was associated with: (1) consistent condom use, (2) condom negotiation self-efficacy or (3) condom use norms among alcohol-using FSWs in Mombasa, Kenya

Gender inequality and the risk of HIV among married couples in North India

This study investigated the distribution and determinants of HIV risks among married couples in North India. Gender inequality emerged as a potential driver of HIV risks in this region. Data collection took place in 2003 in a probability survey of 3,385 couples living in India’s most populous state – Uttar Pradesh – and Uttaranchal. Couples’ analyses utilizing generalized estimating equations showed that compared with husbands, wives were less knowledgeable about HIV (OR=0.31, 95% CI= 0.27–0.36), more likely to consider themselves at risk for infection (OR=6.86, 95% CI= 4.65–10.13), and less likely to feel that a wife had the right to refuse sex with her husband (OR=0.50, 95% CI= 0.44–0.58). The proportion of husbands reporting non-marital sex in the past year was 7.1% and transactional sex in the past year, 2.2%. Among their wives, 73.4% were unaware of their husbands’ non-marital sexual behaviors and only 28.9% of husbands reported condom use during their last non-marital sexual encounter. Logistic regression analyses showed that husbands’ alcohol use, husbands’ mobility, and urban residence were positively associated with husbands’ non-marital sexual behaviors adjusting for other covariates. The data demonstrate that HIV prevention programs among couples in North India should consider both sexual risks and gender inequalities which potentially fuel HIV spread in this region

The Impact of Differences in Methodology and Population Characteristics on the Prevalence of Hypertension in US Adults in 1976-1980 and 1999-2002

Results from the National Health and Nutrition Examination Survey (NHANES) indicate that hypertension prevalence declined by 9% points from 34% in 1976–1980 to 25% in 1999–2002 in adults 20–74 years. The purpose of this study was to estimate the impact on hypertension prevalence of measurement error and selected risk factors

Un análisis multinivel de población y deforestación en el Parque Nacional Sierra de Lacandón (Petén, Guatemala)

Este estudio examina los factores demográficos asociados con la deforestación en el Parque Nacional Sierra de Lacandón (PNSL), Guatemala, utilizando un análisis de regresión multinivel. Más del 10% del PNSL ha sido deforestado desde mediados de la década de 1980, a causa del crecimiento demográfico de la población campesina y su subsiguiente manejo de la tierra. Utilizando un análisis de regresión múltiple de dos niveles, este estudio examina datos demográficos y otras características de los hogares para explicar variaciones en el bosque roturado entre 241 fincas agrícolas en ocho comunidades en el PNSL. Esta metodología, novedosa en el estudio de uso del suelo en los trópicos, toma en cuenta la variación espacial entre comunidades, así como entre hogares. Al usar modelos de multinivel, se puede llegar a resultados mejores sobre los impactos de los factores, tanto a nivel de comunidad como a nivel de hogar sobre la deforestación, con implicaciones más adecuadas para políticas de desarrollo.Aquest estudi examina els factors demogràfics associats amb la desforestació al Parc Nacional Sierra de Lacandon (PNSL), Guatemala, mitjançant una anàlisi de regressió multinivell. Més del 10 % del PNSL ha estat desforestat des de la meitat de la dècada de 1980, com a conseqüència del creixement demogràfic i les pràctiques de gestió agrícola. Utilitzant una anàlisi de regressió múltiple de dos nivells, aquest estudi examina dades demogràfiques i unes altres característiques de les llars per explicar variacions en el bosc artigat entre 241 finques agrícoles en vuit comunitats al PNSL. Aquesta metodologia té en compte la variació especial entre comunitats i entre llars, i abans no havia estat mai aplicada als tròpics. El model de regressió multinivell pot ajudar a explicar millor els impactes de factors propis de les comunitats i de les llars en la desforestació, per tant, pot contribuir a millorar les polítiques de desenvolupament.Cette étude a examiné les facteurs démographiques associés au phénomène de déforestation du Parc National Sierra de Lacandón (PNSL, Guatemala) en utilisant une analyse de régression multi-niveau. Depuis le milieu des années 1980, plus de 10 % du PNSL a été déboisé par la croissance démographique de la population rurale, son besoin en surface et l'utilisation variée de la terre. En utilisant une analyse de régression multiple de deux niveaux, cette étude examine des données démographiques et plusieurs caractéristiques liées aux exploitations, dans le but d'expliquer les variations dans le parc défriché entre 241 propriétés agricoles dans huit communautés du PNSL. Cette méthodologie, nouvelle dans l'étude de l'usage du sol dans les tropiques, prend en compte la variation spatiale entre des communautés ainsi que des exploitations. En utilisant ces modèles de multi-niveaux, on peut arriver à de meilleurs résultats concernant les impacts des facteurs au niveau des communautés et des exploitations concernant la déforestation, avec des résultats plus adapatées pour les politiques de développement.The paper examines depopulation factors associated with deforestation in the Natural park of the Sierra de Lacandón (PNSL), using multi-level regresión analysis. More than 10 percent of the park area has been deforested since the mid 1980s because of rural population growth and agricultural practices. By means of a two-level regression analysis the study use dem ographic and other household data to explain variations in deforested land in 241 agricultural estates in 8 communities of the PNSL. The methodology, not applied before in the tropics, takes into account spatial variations between communities and households. Multilvel regression allows for better results on the impacts of socioeconomic factors on deforestation, both at the community and at the household levels with important implications for development policies

Association of Adolescent Obesity With Risk of Severe Obesity in Adulthood

Although the prevalence of obesity has increased in recent years, individuals who are obese early in life have not been followed over time to determine whether they develop severe obesity in adulthood, thus limiting effective interventions to reduce severe obesity incidence and its potentially life-threatening associated conditions

Socioeconomic Status, Medicaid Coverage, Clinical Comorbidity, and Rehospitalization or Death After an Incident Heart Failure Hospitalization: Atherosclerosis Risk in Communities Cohort (1987 to 2004)

Among heart failure (HF) patients, early readmission or death and repeat hospitalizations may be indicators of poor disease management or more severe disease

Serostatus disclosure to sexual partners among people living with HIV: Examining the roles of partner characteristics and stigma

HIV serostatus disclosure among people living with HIV/AIDS (PLWHA) is an important component of preventing HIV transmission to sexual partners. Due to barriers like stigma, however, many PLWHA do not disclose their serostatus to all sexual partners. This study explored differences in HIV serostatus disclosure based on sexual behavior subgroup [men who have sex with men (MSM), heterosexual men, and women], characteristics of the sexual relationship (relationship type and HIV serostatus of partner), and perceived stigma. We examined disclosure in a sample of 341 PLWHA: 138 MSM, 87 heterosexual men, and 116 heterosexual women who were enrolled in SafeTalk, a randomized, controlled trial of a safer sex intervention. We found that, overall, 79% of participants disclosed their HIV status to all sexual partners in the past 3 months. However, we found important differences in disclosure by subgroup and relationship characteristics. Heterosexual men and women were more likely to disclose their HIV status than MSM (86%, 85%, and 69%, respectively). Additionally, disclosure was more likely among participants with only primary partners than those with only casual or both casual and primary partners (92%, 54%, and 62%, respectively). Participants with only HIV-positive partners were also more likely to disclose than those with only HIV-negative partners, unknown serostatus partners, or partners of mixed serostatus (96%, 85%, 40%, and 60%, respectively). Finally, people who perceived more HIV-related stigma were less likely to disclose their HIV serostatus to partners, regardless of subgroup or relationship characteristics. These findings suggest that interventions to help PLWHA disclose, particularly to serodiscordant casual partners, are needed and will likely benefit from inclusion of stigma reduction components