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

OBJECTIVE: Whether obesity is associated with childhood cognition is unknown. Given the sensitivity of the developing brain to environmental factors, we examined whether early-life weight status was associated with children’s cognition. METHODS: Using data from mother-child pairs enrolled in the HOME Study (2003–2006), we assessed children’s early-life weight status using weight-for-length/height standard deviation (SD) scores. We administered a battery of neuropsychological tests to assess cognition, executive function, and visual-spatial abilities at ages 5 and 8 years. Using linear mixed models, we estimated associations between early-life weight status and cognition. RESULTS: Among 233 children, 167 were lean (≤1SD) and 48 were non-lean (>1SD). After covariate adjustment, the results suggest that full-scale Intelligence Quotient (IQ) scores decreased with 1-unit increase in weight-for-height SD score (β=−1.4, CI: −3.0, 0.1). For individual component scores, with 1-unit increase in weight-for-height SD score, perceptual reasoning (β= −1.7, CI: −3.3, 0.0) and working memory (β: −2.4; CI: −4.4, −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 full-scale IQ scores.