Serum insulin-like growth factor 1 in young children with moderate acute malnutrition: secondary analysis of a randomized trial in Burkina Faso

Insulin-like growth factor 1 (IGF-1) is an important growth factor in childhood. We aimed to investigate the impact of food supplements for treatment of moderate acute malnutrition (MAM) on serum IGF-1 (sIGF-1). Secondary analysis of a randomized 2×2×3 factorial nutrition trial was performed. Children aged 6-23 months with MAM received 2093 kJ/day as lipid-based nutrient supplement (LNS) or corn-soy blend (CSB), containing either dehulled soy or soy isolate and different quantities of dried skimmed milk (0%, 20% or 50% of total protein) for 12 weeks. The trial was double-blind with regard to soy and milk, but not to matrix (LNS vs. CSB). sIGF-1 was measured at inclusion and after 12 weeks supplementation. Of 1609 children enrolled, 1455 (90%) had sIGF-1 measured at both time points. During supplementation sIGF-1 increased 6.7 (95%CI 6.1; 7.3) ng/ml compared with an expected age-dependent decrease of 0.3 (95%CI 0.2; 0.4) ng/ml. Children who received LNS vs. CSB had lower increase in sIGF-1 (-8%, 95%CI -12; -3). The effect of LNS was partly attenuated when sIGF-1 was corrected for inflammation. Children who received soy isolate compared with dehulled soy had higher increase in sIGF-1 (6%, 95%CI 1; 12). Milk content did not affect sIGF-1. Overall, sIGF-1 increased during supplementation. The lower increase with LNS vs. CSB was only partly explained by increased inflammation with LNS, and needs further investigation. Isolate vs. dehulled soy led to a higher increase which may be due to antinutrients in dehulled soy.