Should infants be screened for anaemia? A prospective study investigating the relation between haemoglobin at 8, 12, and 18 months and development at 18 months

Abstract

Aims - To investigate the relation between haemoglobin in children followed longitudinally from 8 to 18 months, and developmental outcome at 18 months. Methods - The Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC) is a longitudinal survey of a geographically defined population of children born in 1991-92. In a randomly selected subsample, blood samples were assayed for Hb at 8, 12, and 18 months; a developmental assessment was carried out at 18 months on 1141 children using the Griffiths Scales of Mental Development. Results - There was a strong quadratic association between Hb at 8 months and performance on the locomotor subscale at 18 months. Average scores increased with increasing Hb up to 95 g/l; there was little additional developmental benefit in Hb levels beyond 95 g/l. Infants with Hb <95 g/l at 8 months of age scored on average 6 points lower on the locomotor subscale than infants with Hb ≥ 95 g/l; infants with Hb <90 g/l at 8 months scored 12 points lower on the locomotor subscale than children with Hb ≥ 90 g/l. Conclusions - Low Hb concentrations (≤ 95 g/l) in 8 month old children are associated with impaired motor development at 18 months. This cut off point corresponds to the 5th centile of Hb at 8 months. The results indicate that if there is an adverse effect of low Hb on developmental outcome, screening may be more effective at 8 months or earlier, rather than after this age. We propose to examine the importance of infant anaemia in relation to more accurate and detailed long term outcomes as the children get older.