Serum iron deficiency was associated with lower cognitive development in the children of the Santal tribe of West Bengal.

Abstract

Poor cognitive scores and low serum iron have been reported among chronically undernourished children from the Santal tribe, West Bengal. Our aim was to investigate the association between iron status and non-verbal cognitive development. We randomly selected 170 children (52.9% boys) aged 5-12years from the Purulia district of West Bengal during 2007-2008 and assessed their iron status: haemoglobin concentration, serum concentration of iron, ferritin, transferrin, total iron-binding capacity and transferrin saturation. Their non-verbal cognitive development was assessed using the Raven's Coloured Progressive Matrices. The haemoglobin concentration, serum iron, serum ferritin and transferrin saturation levels of the 27 children with an intellectual deficit and the 32 who had a below average intelligence quotient (IQ) were significantly lower (P<.05) than the 65 children with an average IQ. A large number of boys (55.6%) and girls (41.7%) who have an intellectual deficit had stage III iron depletion. The cognitive scores of children with stage II and III iron depletion were significantly lower (P<.05) than those with a normal IQ. The iron depletion stage was associated with the severity of non-verbal cognitive impairment and serum ferritin appeared to be a sensitive biomarker for predicting non-verbal cognitive development.