Longitudinal cognitive assessment in healthy late preterm infants

Background: Longitudinal cognitive development in late preterm (LP) infants has not been Received 21 March 2011 previously evaluated, using structured assessments. Received in revised form Aim: To assess longitudinally cognitive development in a population of healthy LP infants 27 June 2011 from 12 months to preschool age. Accepted 19 July 2011 Methods: Sixty-two low-risk LP infants (33-36 weeks gestation) with normal or only minor findings on their cranial ultrasound scans were included in the study. They were assessed Keywords: at 12 and 18 months corrected age using the Bayley Scales of Infant Development II to Late preterm obtain the mental development index (MDI) and then at preschool age (mean age Cognitive outcome 62 7 months) using the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-R). Gender differences Results: The MDI scores obtained at both 12 and 18 months corrected age were within the WPPSI-R reported normative range. Using uncorrected ages, their scores were lower at both ages Longitudinal assessment than those obtained using CA (p < 0.01). Full-scale IQ scores within the reported normal range were obtained at 5 years using the WPPSI-R for all but 6 children. Females had significantly higher scores than males (p < 0.001) for the MDI at both 12 and 18 months corrected and uncorrected age. No gender differences were found at preschool age using the WPPSE-R. Conclusions: Our results suggest that over 90% of the low-risk late preterms reach an MDI and IQ at preschool age within normal range. (C) 2011 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.