Cognitive function at 10 years of age in children who have required neonatal intensive care

To study cognitive function at 10y of age in a cohort of children who required neonatal intensive care within the Uppsala Neonatal Follow-up Study.

226 children, who were born in 1986-1989 and had required neonatal intensive care (NIC) and 72 full-term, healthy control children were enrolled in the study. NIC children were grouped according to gestational age (group I, 23-31 wk; subgroup IA, 23-27 wk; IB 28-31 wk; group II, 32-36 wk; group III, > 36 wk), with infants with congenital malformation (IWCM) included and excluded from the main groups. The Kaufman Assessment Battery for Children (K-ABC) was administered and results were analysed in relation to the K-ABC global scales: sequential, simultaneous, mental processing composite and achievement.

The great majority of children had well-developed cognitive function, reaching scores at an average level or above. When groups were compared, full-term children that required NIC (group III) showed lower scores than controls on all scales measured by the K-ABC. Preterm children from all the studied groups (groups IA, IB, II) showed poorer performance than controls in the simultaneous processing scale, and group IA scored lower than controls in the achievement scale. The incidence of major cognitive impairment (IQ < 70) was low in NIC children (< 5%), but children from group IA showed significant higher frequency of impairment in the simultaneous, mental processing composite and achievement scales. Children from group IA presented a high frequency of discrepancy between the K-ABC scales, with lower simultaneous and higher sequential scores. Analysis with IWCM excluded from the main groups revealed identical results.

Most children who needed neonatal intensive care had developed well their cognitive function at 10 y of age. The long-term effect of neonatal intensive care on cognitive function was more evident in extremely preterm infants (group IA), especially in tasks involving simultaneous ways of processing information.