Cognitive outcome in late preterm babies

Abstract Background Late preterm babies are at risk for delayed cognitive outcome, but little attention has been paid on this issue. There has been a general assumption that this group of babies will have the same development as full-term babies. Objective To compare the cognitive development between late preterm babies and full-term babies. Methods A prospective cohort study was conducted at the Department of Child Health Medical School of Udayana University/Sanglah Hospital. Babies with 34 to 42 weeks of gestational age who were born in Sanglah Hospital between November 1st 2007 and December 31st 2008, were recruited to the study. Cognitive development of each baby was measured by Mullen Scale’s of Early Learning twice, at 7 days and 3 months of age. We used corrected age for late preterm babies and chronological age for fullterm babies. Results The incidence of under-average development for late preterm babies at three months corrected age was 47.8% compared to 4.1% among fullterm babies (P < 0.0001). The relative risk for under-average development among late preterm babies was 11.8 (95%CI 9.95 to 13.75). Multivariate analysis revealed late preterm influenced cognitive significantly with OR 17.01 (95%CI 1.15 to 32.87). Conclusions Cognitive outcome of late preterm babies was delayed compared to full-term babies. [Paediatr Indones. 2010;50:239-244]. Keywords: cognitive outcome, late preterm babies, Mullen Scale of Early Learni ng From the Department of Child Health, Medical School, Udayana University, Denpasar, Indonesia.1 From the Department of Child Health, Medical School, Gadjah Mada University, Yogyakarta, Indonesia.2 Reprint requests to: Ayu Setyorini MD, Department of Child Health, Medical School, Udayana University, Sanglah Hospital, Jl. Pulau Nias, Denpasar, Bali, Indonesia. Tel/Fax. 62-361-244034. E-mail: setyorini_ mestika@yahoo.com L ate preterm babies, who are born within 34 to < 37 weeks of gestational age (GA), are at risk for deterioration because of organ immaturation, medical intervention and its complications, and the effect of condition that cause the prematurity.1 One of the important effect of the deteriorations is delayed cognitive outcome of survived preterm babbies.2-7 Most of the studies on cognitive outcome of preterm babies were conducted on high risk preterm baby group.8-13 Only few studies were conducted on late preterm babies even though this subgroup constituted 70% of the survived preterm babies.14-16 This subgroup also had a little attention in the following observation because of general assumption that this group had a little risk to develop abnormally.17 Intervention for delayed development would have the best result, if conducted as early as possible. One study in Bali reported that stimulation for low birth weight infant already showed result at three