Effects of iron deficiency anemia on cognitive function in children.

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.