Neighborhood contributions to racial and ethnic disparities in obesity among New York City adults

Objectives: We assessed neighborhood confounding on racial/ethnic obesity disparities among adults in New York City after accounting for complex sampling, and how much neighborhood factors (walkability, percentage Black or Hispanic, poverty) contributed to this effect. Methods: We combined New York City Community Health Survey 2002-2004 data with Census 2000 zip code-level data. We estimated odds ratios (ORs) for obesity with 2 sets of regression analyses. First, we used the method incorporating the conditional pseudolikelihood into complex sample adjustment. Second, we compared ORs for race/ethnicity from a conventional multilevel model for each neighborhood factor with those from a hybrid fixed-effect model. Results: The weighted estimate for obesity for Blacks versus Whites (OR = 1.8; 95% confidence interval = 1.6, 2.0) was attenuated when we controlled neighborhood confounding (OR = 1.4; 95% confidence interval = 1.2, 1.6; first analysis). Percentage of Blacks in the neighborhood made a large contribution whereas the walkability contribution was minimal (second analysis). Conclusions: Percentage of Blacks in New York City neighborhoods explained a large portion of the disparity in obesity between Blacks and Whites. The study highlights the importance of estimating valid neighborhood effects for public health surveillance and intervention.