Impacts of Segregation and Community SES on Child Growth Trajectories

Objectives: This study aimed to determine if and to what extent segregation and socioeconomic status (SES) were associated with growth trajectories during early childhood and to evaluate if these associations were moderated by fetal growth or duration of gestation.

Methods: Individual level data were from the Early Childhood Longitudinal Study, Birth Cohort (n=6,650). Community level data were from the RAND Center for Population Health and Health Disparities data. Lagged polynomial growth curve modeling and spline modeling were used to capture the impacts of segregation and community SES on body mass index (BMI) percentile or obesity risk trajectories after adjusting for other covariates. The robustness of the results were evaluated by using alternative definitions of segregation or SES, and fitting alternative modeling with generalized estimating equation.

Results: Significant interactions between segregation and child growth were found. On average BMI percentile of Hispanic was higher than that of non-Hispanic (NH) White (b=0.19, s.e.=0.06, p<0.001). For Hispanic children, increasing levels of community segregation were associated with lower BMI percentiles (b=0.05, s.e.=0.02, p<0.001) at 24 and 48 months. BMI percentile of NH-African American was similar with that of White (b=0.06, s.e.=0.06, p<0.28).  In contrast, for non-Hispanic African American children, increasing levels of segregation were associated with higher BMI percentiles (b=-0.10, s.e.=0.04, p<0.02) at 24 and 48 months. No effect was found in SES.

Discussion: The mechanisms the way segregation affected child growth may require further studies. This study suggested analytic approach that reduces the impact of potential threats to validity in neighborhood studies.