Neighborhood social processes and birthweight disparities in Los Angeles County

Background: Previous research examining the role of neighborhoods in birthweight disparities by race/ethnicity have focused on structural characteristics such as neighborhood poverty. Neighborhood structural characteristics are hypothesized to operate through neighborhood social processes, but evidence to support the role of neighborhood social processes on birthweight is limited. Our analyses extend previous research through exploration of factors such as neighborhood collective efficacy (and its components, social cohesion and trust), disorder, reciprocated exchange, and intergenerational closure on birthweight. Methods: Individual-level information on birthweight and child and maternal characteristics came from geocoded Los Angeles County vital statistics records (2002–2006). Data on neighborhood structural characteristics came from the 2000 decennial census, and information on neighborhood social processes came from interviews and systematic social observations conducted for the 2000–2001 Los Angeles Family and Neighborhood Survey. Neighborhoods were defined as census tracts and linear models of birthweight were estimated using the generalized estimating equation approach to account for clustering. Results: We found important differences by race/ethnicity in the association between neighborhoods and birthweight. We observed positive effects of neighborhood median income on birthweight for non-Latino whites (p<.01) and Latinos (p<.05), but not blacks. For Latinos, the association of neighborhood income with birthweight is through collective efficacy (p<.01) and neighborhood disorder (p<.10); collective efficacy is associated with higher birthweight, while disorder is associated with lower birthweight. Conclusions: The association of neighborhood social processes with birthweight varies by race/ethnicity. Our results suggest potential new neighborhood interventions for improving birth outcomes, particularly among Latinos.