Impact of Early-Life Weight Status on Cognitive Abilities in Children

Abstract

Objective: Whether obesity is associated with childhood cognition is unknown. Given the sensitivity of the developing brain to environmental factors, this study examined whether early-life weight status was associated with children's cognition. Methods: Using data from mother–child pairs enrolled in the Health Outcomes and Measures of the Environment (HOME) Study (2003–2006), children's early-life weight status was assessed using weight-for-length/height standard deviation (SD) scores. A battery of neuropsychological tests was administered to assess cognition, executive function, and visual-spatial abilities at ages 5 and 8 years. Using linear mixed models, associations between early-life weight status and cognition were estimated. Results: Among 233 children, 167 were lean (≤1 SD) and 48 were nonlean (>1 SD). After covariate adjustment, the results suggest that full-scale intelligence quotient scores decreased with a 1-unit increase in weight-for-height SD score (β = –1.4, 95% CI: –3.0 to 0.1). For individual component scores, with a 1-unit increase in weight-for-height SD score, perceptual reasoning (β = –1.7, 95% CI: –3.3 to 0.0) and working memory (β: –2.4, CI: –4.4 to –0.4) scores decreased. Weight status was generally not associated with other cognition measures. Conclusions: Within this cohort of typically developing children, early-life weight status was inversely associated with children's perceptual reasoning and working memory scores and possibly with full-scale intelligent quotient scores.