Assessing mediation of behavioral and stress pathways in the association between neighborhood environments and obesity outcomes

Abstract

Although many studies have reported associations between characteristics of the neighborhood environment and obesity, little is understood about the pathways or mechanisms through which these associations operate. The purpose of this study was to examine possible behavioral and stress pathways hypothesized to mediate the association between neighborhood environments and obesity and whether pathways contribute to different obesity outcomes. Cross-sectional data were used from the 2012–2014 Women and Their Children's Health Study (WaTCH) in Louisiana (N = 909). Participants' neighborhoods, body mass index (BMI) and waist circumference (WC) were objectively measured. The causal inference approach to mediation analysis was used to obtain indirect estimates for self-reported measures of physical activity, low access to food, and depression. The mean BMI was 32.0 kg/m2 and the mean WC was 98.6 cm. The (adverse) neighborhood environment was significantly associated BMI (β = 0.17 kg/m2; 95% Confidence Interval (CI): 0.03, 0.31) and WC (β = 0.64; 95% CI: 0.34, 0.95, after adjusting for covariates. Neither depression, physical activity, nor low food access mediated those associations. Further research that investigates and uses better measures of the behavioral and stress pathways through which the neighborhood environment influences obesity is warranted. Keywords: Mediation analysis, Indirect effects, Body mass index, Waist circumference, Neighborhood environments