Metabolomics in plasma of Malawian children 7 years after surviving severe acute malnutrition : 'ChroSAM' a cohort study

Background: More children are now surviving severe acute malnutrition (SAM), but evidence suggests that early-life malnutrition is associated with increased risk of long-term cardio-metabolic disorders. To better understand potential mechanisms, we studied the metabolite profiles of children seven years after treatment for SAM. Methods: We followed-up children (n=352) treated for SAM in 2006-2007, at Queen Elizabeth Central Hospital, in Malawi. Using nuclear magnetic resonance spectroscopy, tandem mass spectrometry and enzyme-linked immunosorbent assay, we measured circulating metabolites in fasting blood in a subset of SAM survivors (n = 69, 9.6 +/- 1.6 years), siblings (n = 44, 10.5 +/- 2.7 years), and age and sex-matched community controls (n = 37, 9.4 +/- 1.8 years). Data were analysed using univariate and sparse partial least square (sPLS) methods. Differences associated with SAM survival, oedema status, and anthropometry were tested, adjusting for age, sex, HIV, and wealth index. Findings: Based on 194 measured metabolites, the profiles of SAM survivors were similar to those of siblings and community controls. IGF1, creatinine, and FGF21, had loading values >0.3 and ranked stably in the top 10 distinguishing metabolites, but did not differ between SAM survivors and controls with univariate analysis. Current stunting was associated with IGF1 (beta = 15.2, SE = 3.5, partial R-2 = 12%, p < 0.0001) and this relationship could be influenced by early childhood SAM(beta = 17.4, SE = 7.7, partial R-2 = 2.8%, p = 0.025). No metabolites were associated with oedema status, duration of hospital stay, anthropometry measured during hospitalization, nor with changes in anthropometry since hospitalization. Interpretation: In this group of survivors, SAM was not associated with longer-term global metabolic changes 7 years after treatment. However, SAM may influence the relationship between current stunting and IGF1. Further risk markers for NCDs in SAM survivors may only be revealed by direct metabolic challenge or later in life. (C) 2019 The Authors. Published by Elsevier B.V