Efficacy and Safety of Daily Iron Supplementation in Children: Lessons from Three Systematic Reviews and Meta-analyses of Randomized Controlled Trials

Abstract

Objectives: 47% of pre-school children and 25% of school-aged children are anaemic. Daily iron supplementation remains a key anaemia control intervention, but benefits and safety in children are debated. We systematically reviewed evidence for daily iron supplementation in 4-23m, 2-5y and 5-12y children. Methods: Separate searches and systematic-reviews/meta-analyses were performed for each age-group. Electronic databases and other sources were searched for randomized controlled trials comparing daily iron supplementation with control. Random-effects meta-analysis was used. Riskof-bias was estimated using the Cochrane tool. Results: For children 4-23m, 2-5y and 5-12y respectively we identified 9533, 9169 and 16501 citations, from which 35, 15 and 32 eligible studies were identified, of which 9, 0 and 4 were at low overall risk-of-bias. Iron improved haemoglobin and ferritin and, in 4-23 m and 5-12y, reduced anaemia and iron deficiency. In 5-12y, iron improved global cognitive scores (SMD 0.50 [0.11, 0.90], p = 0.01) and in anaemic children, IQ (MD 4.55 [0.16, 8.94], p = 0.04). In 2-5y, limited data