The Impact of Early Iron Supplementation on Neurodevelopmental Outcomes in Infants: A Meta-analysis
DOI:
https://doi.org/10.54361/LJMR.19.2.46Keywords:
Iron Supplementation, Neurodevelopment, Infants, Meta-analysisAbstract
Background: Iron deficiency during the critical window of early life can adversely affect long-term brain development. This systematic review and meta-analysis aimed to quantitatively evaluate the impact of early iron supplementation on neurodevelopmental outcomes in infants to inform clinical practice. Material and Methods: We systematically searched PubMed, Cochrane, and Embase databases from inception to May 2025. We selected randomized controlled trials (RCTs) evaluating iron supplementation in infants aged 0–24 months that reported neurodevelopmental outcomes. The primary outcome measured was the Mental Development Index (MDI), while secondary outcomes included iron status parameters and behavioral assessments. We assessed risk of bias using the Cochrane tool and evaluated the overall quality of evidence using GRADE criteria. Results: Fourteen studies met the inclusion criteria for qualitative synthesis; eight studies (n=561 infants) were eligible for meta-analysis. Iron supplementation was associated with significant improvements in MDI scores (Mean Difference [MD] 2.27; 95% CI: 1.43 to 3.12; I²=18%). Subgroup analyses revealed substantially greater benefits in preterm and low birth weight infants (MD 3.1; 95% CI: 1.8 to 4.4) compared to term infants (MD 1.2; 95% CI: 0.3 to 2.1). Interventions starting earlier (0–3 months) showed greater neurodevelopmental benefits than those starting later (4–6 months). Additionally, supplementation significantly reduced externalizing behavioral problems (Risk Ratio [RR] 0.36; 95% CI: 0.17 to 0.76) and improved hemoglobin levels (MD 0.42 g/dL). Adverse events were rare, with only constipation showing a significant increase (RR 1.23; 95% CI: 1.02 to 1.49). Conclusion: Early iron supplementation positively impacts neurodevelopmental outcomes, with the most pronounced benefits observed in high-risk groups such as preterm and low birth weight infants. Crucially, the timing of supplementation appears vital, with earlier intervention yielding superior cognitive results. These findings strongly support current recommendations for iron supplementation in infancy, specifically prioritizing at-risk populations.
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Copyright (c) 2025 Nouri Mumash, Ahmed S. Mikeal, Mohammed M. Makhzom3, Ibrahim M. Altaib, Ebtihaj S. Durman, Asmaa M. Aqoub, Abdulnasir J. Yunus, Jamal A. Bilrrahal (Author)
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