Acute Undernutrition and Child Development in Low- and Middle-Income Countries: A Meta-analysis

Context The association between linear growth faltering and child development outcomes is generally well recognized; however, the relationship between metrics of acute undernutrition and development has received less attention. Objectives We aimed to quantify the association between metrics of acute undernutrition in childhood with development outcomes in low- and middle-income countries (LMICs). Methods We conducted a systematic literature review of observational studies that assessed the association between metrics of acute undernutrition, including body mass index-for-age z score (BMIZ), midupper arm circumference (MUAC), weight-for-height/-length z score (WHZ/WLZ), wasting (WHZ/WLZ −2), and severe acute malnutrition (SAM) among children under 5 years of age with cognitive, motor, language, and socioemotional development assessed to 19 years of age. We estimated the pooled correlation and standardized mean difference (SMD) for cross-sectional and longitudinal studies. Results A total of 113 studies from 40 LMICs were identified. Metrics of acute undernutrition were associated with lower cognitive and motor development scores. In longitudinal studies that reported multivariable-adjusted estimates for the cognitive domain, SAM was associated with −1.06 SD lower scores (95% CI: −1.41, −0.72) compared with children without SAM. SAM was also associated with lower motor scores in longitudinal studies with unadjusted estimates (SMD: −0.42; 95% CI: −0.68, −0.15). In longitudinal studies with multivariable estimates, wasting was associated with lower motor scores (SMD: −0.30; 95% CI: −0.54, −0.06), but there was no association with language (SMD: −0.08; 95% CI: −0.24, 0.07) or prosocial development scores (SMD: −0.18; 95% CI: −0.38, 0.02). Conclusion Metrics of acute undernutrition in childhood were consistently associated with lower development scores, and the magnitude appeared stronger for children with SAM or wasting.