Summary: While iron supplements help improve symptoms of anemia in young children, they have no impact on growth, cognitive function, behavior or development.
A study in rural Bangladesh has concluded that preventive iron treatment has no impact on young children’s development.
Iron supplements are administered to young children worldwide to prevent anaemia, in line with global guidelines.
Led by WEHI Associate Professor Sant-Rayn Pasricha, in collaboration with Dr Jena Hamadani from the International Center for Diarrheal Diseases Research Bangladesh and Professor Beverley-Ann Biggs from the Doherty Institute, and published in the New England Journal of Medicine, the study measured the impact of iron supplements on child cognitive function, behaviour and development.
Supplements show no impact on development
Iron was provided to eight-month-old children, as both iron drops and home fortification packets (multiple micronutrient powders), and neither intervention improved child development, although both improved anaemia.
The study measured children’s cognitive, language and motor development, as well as behaviour, and growth, including height and weight, and found iron supplements had no impact on any of these areas of development.
Associate Professor Pasricha said the research could lead to major changes in global nutrition policy.
“We have been administering iron supplements to young children worldwide for decades in the belief that it had a positive impact on their development, without proper evidence it was actually beneficial,” he said.
“What we have demonstrated, is that while iron supplements improved anaemia in children, these interventions had no impact on growth, cognitive function, behaviour or development.”
“This has implications for how we treat iron deficiency and anaemia in babies and young children worldwide.”
Guiding future global health policy
Associate Professor Pasricha said anaemia in young children has long been linked with poor health outcomes and developmental delays.
“This led to policies of universal distribution of iron interventions to children, based on the assumption that iron would reverse poor child development,” he said. “Our rigorous study shows this is not the case.”
The study also evaluated adverse side effects in children who took the iron supplements preventatively.
Dr Hamadani said for some of these children the supplements may do more harm than good.
“In children taking iron supplements who did not have anaemia, they may actually have had increased presentations to clinics due to episodes of diarrhoea, possibly indicating iron interventions were doing more harm than good,” she said.
The World Health Organization (WHO) recommends iron supplements are given to all young children in low and middle-income countries where anaemia is common.
“We need to carefully reconsider the use of these interventions based on this study,” Associate Professor Pasricha said.
“It also puts into question the need to screen otherwise healthy, asymptomatic children for anaemia.”
Professor Biggs said she expected the findings to inform future global health policy guidelines about the use of iron interventions in young children.
“This study may also help inform guidelines for the treatment and prevention of anaemia in Indigenous populations in Australia,” she said.
Funding: This work was made possible with funding from the Australian National Health and Medical Research Council, the Government of Bangladesh, Global Affairs Canada, the Swedish International Development Cooperation Agency and the Victorian Government, with support from the Foreign, Commonwealth and Development Office in the United Kingdom.
About this neurodevelopment research news
Author: Samantha Robin
Contact: Samantha Robin – WEHI
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Original Research: Closed access.
“Benefits and Risks of Universal Iron Interventions in Infants” by Sant-Rayn Pasricha et al. NEJM
Benefits and Risks of Universal Iron Interventions in Infants
Universal provision of iron supplements (drops or syrup) or multiple micronutrient powders to young children in low-to-middle-income countries where anemia is prevalent is recommended by the World Health Organization and widely implemented. The functional benefits and safety of these interventions are unclear.
We conducted a three-group, double-blind, double-dummy, individually randomized, placebo-controlled trial to assess the immediate and medium-term benefits and risks of 3 months of daily supplementation with iron syrup or iron-containing multiple micronutrient powders, as compared with placebo, in 8-month-old children in rural Bangladesh.
The primary outcome was cognitive development, as assessed by the cognitive composite score on the Bayley Scales of Infant and Toddler Development, third edition, immediately after completion of the assigned 3-month regimen; scores range from 55 to 145, with higher scores indicating better cognitive performance.
Secondary outcomes included the cognitive composite score at 9 months after completion of the assigned regimen; behavioral, language, and motor development, as well as growth and hematologic markers, immediately after completion and at 9 months after completion; and safety.
We randomly assigned 3300 infants to receive iron syrup (1101 infants), multiple micronutrient powders (1099), or placebo (1100) daily. After completion of the assigned 3-month regimen, no apparent effect on the cognitive composite score was observed with iron syrup as compared with placebo (mean between-group difference in change in score from baseline, −0.30 points; 95% confidence interval [CI], −1.08 to 0.48) or with multiple micronutrient powders as compared with placebo (mean between-group difference in change in score from baseline, 0.23 points; 95% CI, −0.55 to 1.00).
No apparent effect on any other developmental or growth outcome was observed immediately after completion of the assigned regimen or at 9 months after completion.
At 9 months after completion of the assigned regimen, the prevalences of anemia, iron deficiency, and iron deficiency anemia increased in all three trial groups but remained lower among the children who received iron syrup or multiple micronutrient powders than among those who received placebo. The risk of serious adverse events and incidence of symptoms of infection were similar in the three trial groups.
In this trial involving infants in Bangladesh, 3 months of daily supplementation with iron syrup or multiple micronutrient powders did not appear to have an effect on child development or other functional outcomes as compared with placebo.
(Funded by the National Health and Medical Research Council of Australia; BRISC Australian New Zealand Clinical Trials Registry number, ACTRN12617000660381. opens in new tab.)