The effect of the 2009 WIC food package change on childhood obesity varies by gender and initial weight status in Los Angeles County

摘要

Objective: To assess whether the effect of the 2009 women, infants, and children (WIC) food package change on obesity outcomes varies by initial weight status and gender.Methods: Using 2003 to 2016 data from Los Angeles County, we compared growth trajectories and obesity at age 4 years among children exposed to WIC after the food package change (n = 53 075) vs children exposed before (n = 53 075). Analyses were stratified by gender and initial weight status: low weight-for-height z-score (WHZ < 25th percentile), average WHZ (25th < WHZ < 75th percentile), and high WHZ (WHZ > 75th percentile). Within strata, children exposed to the new vs old packages were matched on sociodemographic characteristics and compared using growth models and Poisson regression.