Long-term outcomes after severe childhood malnutrition in adolescents in Malawi (LOSCM): a prospective observational cohort study

Background: Research on long-term outcomes of severe childhood malnutrition is scarce. Existing evidence suggests potential associations with cardiometabolic disease and impaired cognition. We aimed to assess outcomes in adolescents who were exposed to severe childhood malnutrition compared with peers not exposed to severe childhood malnutrition.

Methods: In Long-term Outcomes after Severe Childhood Malnutrition (LOCSM), we followed up adolescents who had 15 years earlier received treatment for severe childhood malnutrition at Queen Elizabeth Central Hospital in Blantyre, Malawi. Adolescents with previous severe childhood malnutrition included in LOCSM had participated in an earlier follow-up study (ChroSAM) at 7 years after treatment for severe childhood malnutrition, where they were compared to siblings and age-matched children in the community without previous severe childhood malnutrition. We measured anthropometry, body composition, strength, glucose tolerance, cognition, behaviour, and mental health during follow-up visits between Sept 9, 2021, and July 22, 2022, comparing outcomes in adolescents exposed to previous severe childhood malnutrition with unexposed siblings and adolescents from the community assessed previously (for ChroSAM) and newly recruited during current follow-up. We used a linear regression model to adjust for age, sex, disability, HIV, and socioeconomic status. This study is registered with the International Standard Randomised Controlled Trial Number Registry (ISRCTN17238083).

Findings: We followed up 168 previously malnourished adolescents (median age 17·1 years [IQR 16·5 to 18·0]), alongside 123 siblings (18·2 years [15·0 to 20·5]), and 89 community adolescents (17·1 years [16·3 to 18·1]). Since last measured 8 years previously, mean height-for-age Z (HAZ) scores had improved in previously malnourished adolescents (difference 0·33 [95% CI 0·20 to 0·46]) and siblings (0·32 [0·09 to 0·55]), but not in community adolescents (difference -0·01 [-0·24 to 0·23]). Previously malnourished adolescents had sustained lower HAZ scores compared with siblings (adjusted difference -0·32 [-0·58 to -0·05]) and community adolescents (-0·21 [-0·52 to 0·10]). The adjusted difference in hand-grip strength between previously malnourished adolescents and community adolescents was -2·0 kg (-4·2 to 0·3). For child behaviour checklist internalising symptom scores, the adjusted difference for previously malnourished adolescents was 2·8 (0·0 to 5·5) compared with siblings and 2·1 (-0·1 to 4·3) compared with community adolescents. No evidence of differences between previously malnourished adolescents and unexposed groups were found in any of the other variables measured.

Interpretation: Catch-up growth into adolescence was modest compared with the rapid improvement seen in childhood, but provides optimism for ongoing recovery of height deficits. We found little evidence of heightened non-communicable disease risk in adolescents exposed to severe childhood malnutrition, although long-term health implications need to be monitored. Further investigation of associated home and environmental factors influencing long-term outcomes is needed to tailor preventive and treatment interventions.

Funding: The Wellcome Trust.