Psychosocial stimulation benefits development in nonanemic children but not in anemic, iron-deficient children

Young children with iron deficiency anemia (IDA) usually have poor development, but there is limited information on their response to psychosocial intervention. We aimed to compare the effects of psychosocial stimulation on the development of children with IDA and children who were neither anemic nor iron deficient (NANI). NANI (n = 209) and IDA (n = 225) children, aged 6-24 mo, from 30 Bangladeshi villages were enrolled in the study. The villages were then randomized to stimulation or control, and all children with IDA received 30 mg iron daily for 6 mo. Stimulation comprised 9 mo weekly play sessions at home. We assessed children's development at baseline and after 9 mo by using the Psychomotor Development Index (PDI) and the Mental Development Index (MDI) of the Bayley Scales of Infant Development-II, and rated their behavior during the test. When we controlled for socioeconomic background, the IDA and NANI groups did not differ in their Bayley scores and behavior at baseline. After 9 mo, the IDA group had improved in iron status compared with baseline but had lower PDI scores and were less responsive to the examiner than the NANI group. Random-effects multilevel regressions of the final Bayley scores of the IDA and NANI groups showed that stimulation improved children's MDI [B ± SE = 5.7 ± 1.9 (95% CI: 2.0, 9.4), P = 0.003], and the interaction between iron status and stimulation showed a suggestive trend (P = 0.10), indicating that children with IDA and NANI responded differently to stimulation, with the NANI group improving more than the IDA group. In addition to iron treatment, children with IDA may require more intense or longer interventions than NANI children.