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Background: Despite 50 years since the passage of the Fair Housing Act of 1968, the majority of black Americans continue to live in highly segregated communities. Differing exposure to obesogenic environments in segregated neighborhoods may contribute to racial disparities in obesity prevalence.Methods: We used prospective data from the Coronary Artery Risk Development in Young Adults (CARDIA) study to examine associations between levels of neighborhood-level racial residential segregation and incident obesity in black men and women. Obesity, determined by measured anthropometry, and residential segregation, measured using the local Gi*statistic, were recorded at baseline and follow-up at years 7, 10, 15, 20, and 25. We used marginal structural survival models to account for time-dependent confounding and for loss to follow-up.Results: Black women living in highly segregated neighborhoods at the prior exam were 30% more likely to become obese during the follow-up period as compared with women living in neighborhoods with low levels of segregation after adjustment for sociodemographic and cardiovascular risk covariates (hazard ratio = 1.3 [95% confidence interval = 1.0, 1.7]). Cumulatively high exposure to segregation averaged across time points was associated with 50% higher hazard of obesity (hazard ratio = 1.5 [95% confidence interval = 1.0, 2.3]) among women. We observed few differences in obesity incidence among men by segregation levels.Conclusions: Fewer health-promoting resources, stressful neighborhood context, and social norms that are less stigmatizing of obesity may contribute to these findings, but more research on specific pathways leading from segregation to obesity is needed to understand differing patterns between men and women. [ABSTRACT FROM AUTHOR]

Background: Previous US population-based studies have found that body weight may be underestimated when self-reported. However, this research may not apply to all US Hispanics/Latinos, many of whom are immigrants with distinct cultural orientations to ideal body size. We assessed the data quality and accuracy of self-reported weight in a diverse, community-based, US sample of primarily foreign-born Hispanic/Latino adults.Methods: Using baseline data (2008-2011) from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), we described the difference between contemporaneous self-reported and measured current body weight (n = 16,119) and used multivariate adjusted models to establish whether the observed trends in misreporting in potential predictors of inaccuracy persisted after adjustment for other predictors. Last, we described the weighted percentage agreement in body mass classification using either self-reported or measured weight (n = 16,110).Results: Self-reported weight was well correlated with (r = 0.95) and on average 0.23 kg greater than measured weight. The range of this misreporting was large and several factors were associated with misreporting: age group, gender, body mass categories, nativity, study site by background, unit of self-report (kg or lb), and end-digit preference. The percentage agreement of body mass classification using self-reported versus measured weight was 86% and varied across prevalent health conditions.Conclusions: The direction of misreporting in self-reported weight, and thus the anticipated bias in obesity prevalence estimates based on self-reported weights, may differ in US Hispanic/Latinos from that found in prior studies. Future investigations using self-reported body weight in US Hispanic/Latinos should consider this information for bias analyses.See video abstract at, http://links.lww.com/EDE/B276. [ABSTRACT FROM AUTHOR]

Background: Although it is clear that there are short-term effects of sodium intake on blood pressure, little is known about the most relevant timing of sodium exposure for the onset of hypertension. This question can be addressed only in cohorts with repeated measures of sodium intake.Methods: Using up to seven measures of dietary sodium intake and blood pressure between 1991 and 2009, we compared the association of baseline, mean, and most recent sodium intake with incident hypertension, in 6578 adults enrolled in the China Health and Nutrition Survey (age 18 to 65 years and free of hypertension at baseline). We used survival methods that account for the interval-censored nature of this study and inverse-probability weights to generate adjusted survival curves and time-specific cumulative risk differences; hazard ratios were also estimated.Results: Baseline sodium intake was not associated with incident hypertension. For the mean and most recent measures, the probability of hypertension-free survival was the lowest among those with the highest sodium intake compared with all other intake groups across the entire follow-up. In addition, the most recent sodium intake had a positive dose-response association with incident hypertension (risk difference at 11 years of follow-up = 0.04 [95% confidence interval = 0.00 to 0.08], 0.06 [0.02 to 0.11], 0.18 [0.12 to 0.24], and 0.20 [0.12 to 0.27] for the second to fifth sodium-intake groups compared with the lowest group, respectively).Conclusion: We found that, among the various time frames, the most recent exposure to sodium was most strongly associated with incident hypertension. [ABSTRACT FROM AUTHOR]

Background: Previous studies on the relationship of neighborhood disadvantage with alcohol use or misuse have often controlled for individual characteristics on the causal pathway, such as income-thus potentially underestimating the relationship between disadvantage and alcohol consumption.Methods: We used data from the Coronary Artery Risk Development in Young Adults study of 5115 adults aged 18-30 years at baseline and interviewed 7 times between 1985 and 2006. We estimated marginal structural models using inverse probability-of-treatment and censoring weights to assess the association between point-in-time/cumulative exposure to neighborhood poverty (proportion of census tract residents living in poverty) and alcohol use/binging, after accounting for time-dependent confounders including income, education, and occupation.Results: The log-normal model was used to estimate treatment weights while accounting for highly-skewed continuous neighborhood poverty data. In the weighted model, a one-unit increase in neighborhood poverty at the prior examination was associated with a 86% increase in the odds of binging (OR = 1.86 [95% confidence interval = 1.14-3.03]); the estimate from a standard generalized-estimating-equations model controlling for baseline and time-varying covariates was 1.47 (0.96-2.25). The inverse probability-of-treatment and censoring weighted estimate of the relative increase in the number of weekly drinks in the past year associated with cumulative neighborhood poverty was 1.53 (1.02-2.27); the estimate from a standard model was 1.16 (0.83-1.62).Conclusions: Cumulative and point-in-time measures of neighborhood poverty are important predictors of alcohol consumption. Estimators that more closely approximate a causal effect of neighborhood poverty on alcohol provided a stronger estimate than estimators from traditional regression models. [ABSTRACT FROM AUTHOR]

Background: Cohort analyses suggesting that breast-feeding protects against being overweight have been criticized for inadequately controlling for confounding associated with the self-selection of feeding practices.Methods: Using nationally representative U.S. data from the National Longitudinal Study of Adolescent Health (1994-1996), we performed traditional cohort analyses (n = 11,998) using logistic regression to estimate the relation between breast-feeding and adolescent overweight (body mass index > or =85 percentile, based on year 2000 CDC growth charts), controlling for known potential confounders. Breast-feeding also was assessed in a subsample of 850 sibling pairs to account for unmeasured genetic and environmental factors.Results: Among girls in the full cohort, the odds of being overweight declined among those who had been breast-fed at least 9 months; odds ratios ranged from 0.90 (95% confidence interval = 0.74-1.09) for <3 months of breast-feeding to 0.78 (0.64-0.96) for > or =9 months. A similar effect was seen in boys, although these trends were less consistent. In contrast, an analysis of sibling pairs provided no evidence of breast-feeding effects on weight within discordant trends.Conclusion: Cohort data indicate that odds of being overweight decrease as breast-feeding duration increases, at least among girls. However, sibling analyses suggest that this relationship may not be causal but rather attributable to unmeasured confounding related to mothers' choice to breast-feed, or to other childhood risk factors for overweight. Our results illustrate the utility of sibling analyses in understanding the true effect of early life exposures (such as breast-feeding) on health outcomes over time, independent of confounding factors that may not be satisfactorily controlled using traditional prospective cohort methods. [ABSTRACT FROM AUTHOR]

Cohort analyses suggesting that breast-feeding protects against being overweight have been criticized for inadequately controlling for confounding associated with the self-selection of feeding practices.Using nationally representative U.S. data from the National Longitudinal Study of Adolescent Health (1994-1996), we performed traditional cohort analyses (n = 11,998) using logistic regression to estimate the relation between breast-feeding and adolescent overweight (body mass index ≥85 percentile, based on year 2000 CDC growth charts), controlling for known potential confounders. Breast-feeding also was assessed in a subsample of 850 sibling pairs to account for unmeasured genetic and environmental factors.Among girls in the full cohort, the odds of being overweight declined among those who had been breast-fed at least 9 months; odds ratios ranged from 0.90 (95% confidence interval = 0.74-1.09) for <3 months of breast-feeding to 0.78 (0.64-0.96) for ≥9 months. A similar effect was seen in boys, although these trends were less consistent. In contrast, an analysis of sibling pairs provided no evidence of breast-feeding effects on weight within discordant trends.Cohort data indicate that odds of being overweight decrease as breast-feeding duration increases, at least among girls. However, sibling analyses suggest that this relationship may not be causal but rather attributable to unmeasured confounding related to mothers’ choice to breast-feed, or to other childhood risk factors for overweight. Our results illustrate the utility of sibling analyses in understanding the true effect of early life exposures (such as breast-feeding) on health outcomes over time, independent of confounding factors that may not be satisfactorily controlled using traditional prospective cohort methods. [ABSTRACT FROM AUTHOR]