Growth and cognition over eight years in three sites of the MAL-ED cohort study

The objective of this study was to examine if height at 2 years, 5 years, and 6-8 years of age was related to school-age cognitive development in low resource settings. Some studies report improved scores in those who catch up, while others found no improvement. We hypothesize that persistent stunting will be negatively associated with cognition and that children who experienced catch-up growth would show improved cognition.Follow-up anthropometry and cognitive assessments at 6-8 years were completed in the Brazil, South Africa, and Tanzania MAL-ED cohorts. Semantic and phonemic fluency and reasoning skills were assessed with the Developmental NEuroPSYchological test and Raven Coloured Matrices, respectively. Stunting at 2, 5, and 6-8 years was used to categorize growth into persistently stunted, early catch-up, late catch-up, and never stunted. Multivariable linear regression was used to estimate relationships between linear growth, stunting, and catch-up growth and 6-8-year-old cognition.Stunting prevalence decreased with each follow-up assessment from 40.1% at 2 years to 13.4% at 6-8 years. Height at each age was negatively associated with cognition (Semantic Fluency: 0.2 z-scores, 95% CI: 0.1, 0.3). Persistent stunting was associated with decreased cognitive scores at 6-8 years (Semantic Fluency: -0.4 z-scores, 95% CI: -0.8, -0.03). Children with catch-up growth, both early (Semantic Fluency: -0.4 z-scores, 95% CI: -0.6, -0.1) and late (Semantic Fluency: -0.4 z-scores, 95% CI: -0.8, -0.1), did not have improved scores compared to those persistently stuntedLinear growth at 2 years remains an important indicator of cognitive development in late childhood. Efforts to reduce early stunting may continue as catch-up growth is not always associated with improved cognitive functioning.