Effects of iron supplementation of LBW infants on cognition and behavior at 3 years

• OBJECTIVE: Low birth weight (LBW) infants are at increased risk of cognitive and behavioral problems and at risk for iron deficiency, which is associated with impaired neurodevelopment. We hypothesized that iron supplementation of LBW infants would improve cognitive scores and reduce behavioral problems. METHODS: In a randomized controlled trial, 285 marginally LBW (2000-2500 g) infants received 0, 1, or 2 mg/kg/day of iron supplements from 6 weeks to 6 months of age. At 3.5 years of age, these infants and 95 normal birth weight controls were assessed with a psychometric test (Wechsler Preschool and Primary Scale of Intelligence) and a questionnaire of behavioral problems (Child Behavior Checklist; CBCL). RESULTS: There were no significant differences in IQ between the LBW groups or LBW infants versus controls. Mean (SD) full-scale IQ was 105.2 (14.5), 104.2 (14.7), and 104.5 (12.7) in the placebo, 1 mg, and 2 mg groups, respectively (P = .924). However, for behavioral problems, there was a significant effect of intervention. The prevalence of children with CBCL scores above the US subclinical cutoff was 12.7%, 2.9%, and 2.7% in the placebo, 1-mg, and 2-mg groups, respectively (P = .027), compared with 3.2% in controls. Relative risk (95% confidence interval) for CBCL score above cutoff in placebo-treated children versus supplemented was 4.5 (1.4-14.2). CONCLUSIONS: Early iron supplementation of marginally LBW infants does not affect cognitive functions at 3.5 years of age but significantly reduces the prevalence of behavioral problems. The study suggests a causal relation between infant iron deficiency and later behavioral problems.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Pediatrik (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Pediatrics (hsv//eng)

Keyword

behavioral problems

children

cognitive score

iron

infant

iron deficiency

iron deficiency anemia

low birth weight

neurodevelopment

preterm

randomized controlled trial

small for gestational age

Publication and Content Type

ref (subject category)

art (subject category)