An international team measured the effects of iron supplementation and anthelmintic treatment on iron status, anemia, growth, morbidity, and development of preschool children in Zanzibar, Tanzania.
A total of 614 children, aged 6-59 months, were included in the double-blind, placebo-controlled trial.
Development of language and motor skills, assessed by parental interview before and after treatment in age-appropriate subgroups, were measured.
Before intervention, anemia was prevalent and severe, and geohelminth infections were prevalent and light. Plasmodium falciparum infection was nearly universal.
| Iron supplementation only improved motor development in children with severe anemia.
| British Medical Journal |
Iron supplementation significantly improved iron status, but not hemoglobin status. It also improved language development by 0.8 points on the 20-point scale.
In addition, iron supplementation improved motor development. However, this effect was modified by baseline hemoglobin concentrations and was apparent only in children with baseline hemoglobin concentrations less than 90 g/l.
In children with a baseline hemoglobin concentration of 68 g/l (one standard deviation below the mean value), iron treatment increased scores by 1.1 points on the 18-point motor scale.
The researchers found that mebendazole significantly reduced the number and severity of infections caused by Ascaris lumbricoides and Trichuris trichiura, but not by hookworms.
Mebendazole increased development scores by 0.4 points on the motor scale and 0.3 points on the language scale.
Rebecca J. Stoltzfus, of Johns Hopkins University, Baltimore, Maryland, USA, said on behalf of her colleagues, "Iron supplementation improved motor and language development of preschool children in rural Africa.
"The effects of iron on motor development were limited to children with more severe anemia."
"Mebendazole had a positive effect on motor and language development, but this was not statistically significant," she concluded.