Growth in early life and physical and intellectual development at school age: a cohort study

The association between growth during early life and subsequent cognitive development and physical outcomes are not widely known in low-resource settings. We examined the postnatal weight and height gain through early life and related these to nutritional status and intellectual development at age 7-9 years. Mothers had been enrolled into a RCT to evaluate the effect of prenatal micronutrients supplementation on birth weight. Their children born in 2004 had height and weight measured at 6, 12, 18 and 24 months of age and were followed up between October 2012 and September 2013 (at ages 7-9 years, N=650). Height-for-age, weight-for-age and BMI-for-age were used to describe nutritional status and the Wechsler intelligence scale for children (WISC-IV) was used to measure intellectual function. Multilevel linear and logistic modelling was used to estimate the association between growth on subsequent growth and intellectual function. After adjustment, weight gain during 6-12 months was associated with full-scale intelligence quotient (FSIQ), verbal comprehension index (VCI), working memory index (WMI) and perceptual reasoning index (PRI). Weight gain during early life was associated with subsequent nutritional status. For every 1 kg increase in weight during 0-6 months, the ORs for underweight, thinness and stunting at 7-9 years were 0.19 (95%CI: 0.09-0.37), 0.34 (95%CI: 0.19-0.59) and 0.40 (95%CI: 0.19-0.83) respectively. Weight gain during 6-12 months and 18-24 months was also associated with lower risk of being underweight. Weight gain during early life was associated with better growth outcomes and improved intellectual development in young school-aged children.