Cross-Sectional Associations of Built and Social Neighborhood Environment Variables with Body Mass Index in a Large Sample of Urban Predominantly African American Children.

Background and
Objectives: Neighborhood environments may play a role in the development of child obesity by providing or limiting opportunities for children to be physically active and access healthy food near the home. This study quantifies associations between the neighborhood built and social environment and age- and sex- standardized body mass index (BMI) z-scores in a predominantly African American urban sample.
Methods: Electronic health record data from a pediatric integrated delivery system (N = 26,460 children, 6 to 19 years old in Philadelphia in 2014) were linked to eight built and social neighborhood environment characteristics. Generalized estimating equations were used to obtain adjusted associations between neighborhood features and age- and sex-adjusted BMI Z-score. Interactions between built and social exposures were examined, as well as effect modification by age, sex, neighborhood socioeconomic status, and population density.
Results: Of 26,460 children, 17% were overweight and 21% were obese. After adjustment for individual- and neighborhood-level confounders, higher neighborhood greenness and higher walkability were associated with lower BMI z-score [mean difference per standard deviation (SD): -0.069 (95% confidence interval: [-0.108 to -0.031] and -0.051 [-0.085, -0.017], respectively)]. Higher levels of neighborhood food and physical activity resources were associated with higher BMI z-score [mean difference per SD 0.031 (0.012 and 0.050)]. We observed no interaction between the built and social neighborhood measures.
Conclusion: Policies to promote walkability and greening of urban neighborhoods may contribute to preventing obesity in children.