Acute undernutrition and child development in low- and middle-income countries: a meta-analysis

Abstract

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 acute undernutrition in childhood with development outcomes in low- and middle-income countries (LMIC). 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), mid-upper 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 socio-emotional 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 outcomes. 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) as compared to non-SAM children. 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) and 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.