Insulin-like growth factor 1 (IGF-1) is an important growth factor in childhood. We aimed to investigate the impact of food supplements for the treatment of moderate acute malnutrition (MAM) on serum IGF-1 (sIGF-1). Secondary analysis of a randomised 2 × 2 × 3 factorial nutrition trial was performed. Children aged 6–23 months with MAM received 2093 kJ/d as lipid-based nutrient supplement (LNS) or corn soy blend (CSB), containing either dehulled soya or soya 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 soya and milk but not to matrix (LNS v. CSB). sIGF-1 was measured at inclusion and after 12 weeks of 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 v. CSB had a 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 soya isolate compared with dehulled soya had a 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 v. CSB was only partly explained by increased inflammation with LNS and needs further investigation. Isolate v. dehulled soya led to a higher increase which may be due to antinutrients in dehulled soya.
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.
BACKGROUND
Serum insulin-like growth factor 1 (sIGF-1) is an important growth factor in childhood. However, studies on sIGF-1 among children from low-income countries are few, and the role of body composition is unknown.
OBJECTIVES
To assess the associations of anthropometry, body composition, inflammation, and breastfeeding with sIGF-1 among children with moderate acute malnutrition (MAM).
METHODS
A cross-sectional study based on admission data from 6 to 23-mo-old children with MAM participating in a nutrition intervention trial (Treatfood) in Burkina Faso. Linear regression analysis was used to identify correlates of sIGF-1.
RESULTS
Among 1546 children, the median (IQR) sIGF-1 was 12 (8.2-18.3) ng/mL. sIGF-1 was highest at 6 mo, with a nadir ∼10-11 mo, and higher in girls than boys. Length-for-age z score (LAZ), weight-for-length z score (WLZ), and midupper arm circumference were positively associated with sIGF-1 (P ≤ 0.001). Fat-free mass (FFM) was also positively associated, as sIGF-1 increased 1.5 (95% CI: 0.5, 2.5) ng/mL for each 1-kg increase in FFM. However, the association disappeared after adjustment for height. Elevated serum C-reactive protein and α1-acid glycoprotein were negatively associated with sIGF-1 (P ≤ 0.001), as was fever (P < 0.001) but not a positive malaria test per se (P = 0.15). Children never breastfed had lower sIGF-1 (-5.1; 95% CI: -9.8, -0.3).
CONCLUSIONS
LAZ and WLZ were positively and inflammation negatively associated with sIGF-1. As all children were moderately malnourished and many had inflammation, this probably explains the very low median sIGF-1. The association of FFM with sIGF-1 was fully explained by height. There was a marked age pattern, with a nadir in late infancy, confirming findings from smaller studies from well-nourished populations. There is a need for prospective studies to disentangle the role of sIGF-1 in growth and health. This trial was registered at https://www.isrctn.com as ISRCTN42569496.