Disertasi

Optimized complementary feeding improves the effect of Iron supplementation on Micronutrient status, Gut microbiota and Growth of 12-23-month old Myanmar children: A Field Randomized Controlled Trial.

Children under 2-years of age are at high risk of micronutrient deficiencies especially iron deficiency (ID), partly due to poor complementary feeding practices. To improve feeding practices, local food-based complementary feeding recommendations (CFR) are needed. Iron supplementation is widely used to treat ID in developing countries; however, its potential effects on other micronutrients and growth are of concern. Iron fortification had shown negative impact on gut microbiota with increased growth of gut pathogens due to increased unabsorbed iron. It was assumed that iron supplementation may have similar impact on gut microbiota but has not yet been explored. On the other hand, if iron supplementation is given with optimized diet using CFRs, nutritional status of children would be improved with less adverse effects on other micronutrients status and growth. The study investigated the effect of iron supplementation; given with or without optimized diet; on micronutrient status, gut microbiota and growth of under 2-year Myanmar children. A randomizedcontrolled trial (NCT01758159) was conducted for 24 weeks among 12-23 month old children from Ayeyarwady, Myanmar. Optimized CFRs based on locally available foods were developed by Linear Programming approach. Randomization by village for CFRs or non-CFRs and by child (n=433) for iron supplements or placebo, created: 1.CFR+Fe (n=112); 2.CFR-alone (n=112); 3.Fe-alone (n=105); or 4.Placebo (n=104) groups. Mothers from CFR-groups received education on CFRs and children from Fe groups received 15mg Ferric NaEDTA daily. Serum for ferritin (SF), transferrinreceptor (sTfR), zinc, retinol-binding-protein (RBP), C-reactive protein and α-1 acid glycoprotein; stool for gut microbiota (Bifidobacteria, Lactobacilli, Enterobacteriaceae, E.coli, EPEC, EAEC and ETEC) were measured at baseline and endline. At baseline, 88.4% of children were anemic (Hb < 110g/L); after adjusting for infection, 74.4% had ID (SF < 12μg/L and/or sTfR > 8.3mg/L) 68.9% had irondeficiency-anemia (IDA) (Hb < 110g/L and ID), and 41.3% had low serum zinc status (serum zinc < 10.7µmol/L). Iron supplementation reduced anemia, ID and IDA whether or not it was given with optimized diet. However, iron supplementation increased the risk of low serum zinc and stunting when it is given without optimized diet. These adverse effects were not seen when iron supplementation was given with optimized diet. No significant difference was found in gut microbiota composition among groups. In conclusion, iron supplementation should be given together with optimized diet to reduce its adverse effect on other micronutrients status and growth to best improve nutritional status of these children.
Key words Complementary feeding recommendations, iron supplementation, iron deficiency anemia, zinc deficiency, gut microbiota, Myanmar.