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.

Conflict of interest statement

Competing financial interests: The authors declared no conflict of interest.

© 2018 The Obesity Society.

Figures

Figure 1

Adjusted Restricted Cubic Polynomial Spline of Weight-For-Height Z-Scores and Children’s Full-Scale IQ, Perceptual Reasoning Index, Working Memory Index, and Processing Speed Index at 5 or 8 Years of Age a aAdjusted for continuous variables maternal age, BMI, IQ, child’s birthweight, age at outcome measurement, and maternal cotinine concentration (mean of log10-transformed cotinine concentrations during 16 and 26 weeks of pregnancy); and categorical variables maternal education (high school graduate or less, tech school or some college, college graduate or above), marital status (married, unmarried), length of breastfeeding (0 month, ≤6 months, >6 months), child’s sex (Male, Female), race (non-Hispanic White, non-Hispanic Black, other).

Figure 2

Adjusted Restricted Cubic Polynomial Spline of Weight-For-Height Z-Scores and Children’s Hit Reaction Time T-score at 5 or 8 Years of Age a aAdjusted for continuous variables maternal age, BMI, IQ, child’s birthweight, age at outcome measurement, and maternal cotinine concentration (mean of log10-transformed cotinine concentrations during 16 and 26 weeks of pregnancy); and categorical variables maternal education (high school graduate or less, tech school or some college, college graduate or above), marital status (married, unmarried), length of breastfeeding (0 month, ≤6 months, >6 months), child’s sex (Male, Female), race (non-Hispanic White, non-Hispanic Black, other).