Objective: To examine the effects of iron deficiency anemia on cognitive function and intelligence in children.
Methods: Matched case-control study was carried out with 30 children (aged 6-12 years) with iron deficiency anemia (IDA) but without any chronic disease and with normal neuromotor development. The WISC-R intelligence test was performed before and after 4-6 months of iron/vitamin treatment (5 mg iron/kg/day as iron(III)-hydroxide polymaltose complex, IPC, and multivitamin preparation). Pre- and post-treatment IQ scores of the IDA group were evaluated and compared to the control group.
Results: Treatment and control groups were similar in terms of age and gender (mean age 9.1 +/- 1.9 years for IDA group, 8.8 +/- 1.5 years for controls, 37 % versus 40 % girls, respectively). Mean total IQ score of the IDA group was 12.9 points lower than that of the control group and this was statistically significant (p < 0.01). Although a highly significant increase of 4.8 points in total IQ was found after treatment with IPC in the IDA group (p < 0.01), post-treatment mean total IQ score of the IDA group was 8.2 points lower than that of the control group. However this difference of 8.2 points was not statistically significant (p > 0.05). There were significant differences in the subtests of WISC-R between the pre-treatment IDA group and the control group. A significant improvement was found especially in these subtests following treatment.
Conclusion: Iron deficiency anemia in children can affect long-term cognitive function. The WISC-R intelligence test subsets and pre- and post-treatment IQ scores of the IDA group were significantly differing from control group.