Effectiveness of weekly multiple micronutrients vs. two levels of iron supplements to improve anemia, micronutrient status and cognitive performance in Senegalese school children.

摘要

Children (n = 359) in three regions of Senegal received 30 mg iron + 200 ug folic acid (Fe30 + FA), 60 mg iron + 400 ug folic acid (Fe60 + FA), multiple micronutrients (including 30 mg iron, 200 ug folic acid) (MMN), or a placebo weekly for 17--20 weeks in school. Prevalence of malaria (49.3%), anemia (27.6%), intestinal parasites and Schistosome haematobium infection was high at baseline. Children with malaria had higher serum TfR (8.1 vs. 7.1 mg/L, P = 0.030) and ZPP in unwashed erythrocytes (68.1 vs. 59.9 umol/mol heme, P = 0.027), but similar ZPP concentrations in washed erythrocytes compared to those without malaria. Prevalence of iron deficiency, assessed by elevated ZPP (washed erythrocytes) and transferrin receptors (TfR) was 21--24% at baseline in children without malaria, was reduced by Iron60 + FA supplementation compared to placebo ( P = 0.025). Vitamin A deficiency, assessed by serum retinol binding protein, was prevalent at baseline (37.6%), but fell to 11% after MMN supplements (containing 800 ug retinol/tablet), compared to 29% in the placebo group ( P = 0.006). Marginal and severe folate deficiency (plasma folate 13.6 nmol/L) was 69% at baseline with fewer deficient cases in children with malaria (57.5 vs. 80.3%, P = 0.006). Plasma folate increased after Iron60 + FA supplements (3.4 vs. 2.6 nmol/L in placebo group, P = 0.018) and folate deficiency (13.6 nmol/L) was reduced by Iron60 + FA and Iron30 + FA supplements (P 0.001, P = 0.048 compared to the placebo). Elevated plasma vitamin B-12 concentrations (>681 pmol/L, the 95th percentile for U.S. children) were common (25.3%), but there were surprisingly few low values (148 pmol/L, 4.9%). Plasma vitamin B-12 was predicted by region (P = 0.049), body mass index Z score (P = 0.004) and giardia ( P = 0.037) in the total sample (n = 315) and also by serum albumin (P = 0.025) in a subgroup with liver function tests (n = 39). Elevated concentrations were predicted by region (P 0.001), poor general health (P = 0.003), female gender (P = 0.004) and infection with intestinal parasites ( P = 0.045) in the total sample. This research provides evidence of widespread micronutrient deficiencies, and of improvements in iron, vitamin A and folate status after short-term weekly supplementation of these children.