Iron status at 1 and 6 years versus developmental scores at 6 years in a well-nourished affluent population

Aim: To examine the association between iron status at 1 and 6 years with development at 6 years. Methods: In a longitudinal study of children (n = 77), iron status was measured at 1 and 6 years and the Icelandic Developmental Inventory, which evaluates children's motor and verbal development, was filled in by mothers near the children's sixth birthday. Results: Children, iron-deficient at 1 year (n = 10), had lower fine motor development scores at 6 years than non-iron-deficient (n = 56) (46.7 ± 4.1 vs. 49.3 ± 2.0; p = 0.011). Fine motor scores were also lower in children with depleted iron stores at 1 year (n = 26) than non-iron-depleted children (n = 40) (48.0 ± 3.3 vs. 49.5 ± 1.8; p = 0.045). Multiple regression analyses, with iron status indices at 6 years, showed that mean corpuscular volume along with male gender predicted significantly positively for expression (adj. R ² = 0.15; p = 0.018; n = 73), while regression analyses, including iron status at 1 and 6 years, showed that haemoglobin at 6 years was positively associated with gross motor (adj. R² = 0.05; p = 0.038; n = 63). Conclusions: In an affluent society, iron deficiency and depleted iron stores at 1 year may contribute to worse fine motor developmental scores at 6 years, while low mean corpuscular volume and haemoglobin at 6 years might affect subsequent expression and gross motor scores negatively.