Iron status and developmental scores in 6-year-olds highlights ongoing need to tackle iron deficiency in infants

To investigate iron status and developmental scores at 6 years of age in a population with decreased prevalence of iron deficiency in infancy. Iron status at 6 years and tracking from 12 months were also studied.

Children (n = 143) born in Iceland in 2005 were followed up at the age of six. Motor and verbal development was assessed by a parental questionnaire, and iron status was assessed by Hb, MCV and serum ferritin (SF). Iron depletion was defined as SF <15 μg/L and deficiency as MCV <76 fL and SF <15 μg/L.

Iron depletion was observed in 5.6% of 6-year-olds, and 1.4% were iron deficient. Self-help (subset in motor development) differed by -4.14 (95% CI = -7.61, -0.67), between those iron depleted at 12 months (n = 6) and those nondepleted (n = 102), adjusted for maternal education. The combined motor developmental score seemed lower in iron depleted infants, although of borderline significance (p = 0.066). MCV concentration tracked from 12 months to 6 years (r = 0.31, p < 0.002), but Hb and SF did not.

Improved iron status at 12 months and 6 years has diminished the public health threat associated with iron depletion in the population studied, but iron depletion and development still associate weakly. Action to prevent iron depletion in infancy remains important.