Iron Suplementation Starting at 12 Months of Age and Developmental Outcomes: Who Benefits?

Abstract

Objectives: Iron deficiency has been linked with reduced developmental outcomes in children, however results are varied. This study aims to investigate the benefit of iron supplementation on developmental outcomes in under-two year old children. Methods: A randomized, double-blinded controlled trial was conducted in Lombok, West Nusa Tenggara Province, Indonesia (ClinicalTrials.gov Identifier: NCT01504633). Two groups (n=44/group) of 12-17 mo children were compared: Placebo and Fe-group (16mg elemental iron/day). Indicators of sub-clinical inflammation (CRP, AGP), iron status (serum ferritin/SF, transferin receptor/sTfR, body iron store/BIS), hemoglobin and development (using BSID II as mental/MDI, psychomotor/PDI and behavior/BRS scores) were assessed at baseline and after 24-week supplementation (endline). Results: Both groups were comparable at baseline (92% anemia, 66% iron deficiency/ID, 62% IDA). Hemoglobin and iron status indicators were significantly higher at endline in Fe-group, also there were significant decrease in prevalence of anemia, ID and IDA (p<0.001). However there is no difference in MDI, PDI and BRS scores between placebo and Fe-group at the endline nor change of these scores.  When stratified by ID and anemia at baseline, iron supplementation can only prevent significant decrease in MDI in the initially non-anemic subjects. Conclusions: Within the regime of iron dosage used in this study (equivalent to 2mg/kg.day) iron supplementation improved hemoglobin and iron status indicators but did not benefit developmental outcomes.  Iron intervention delivered for children <12mo may be too late due to prolonged deficiency.  Further studies when iron intervention is started at earlier age or even prenatally are needed.