Prediction of Neurodevelopmental and Sensory Outcome at 5 Years in Norwegian Children Born Extremely Preterm

Abstract

OBJECTIVE: To examine the prevalence of neurodevelopmental disability and the predictive value of pre-, peri-, and postnatal data on neurologic, sensory, cognitive, and motor function in children born extremely preterm. METHODS: This was a prospective observational study of all infants born in Norway between 1999 and 2000 with gestational ages between 22 and 27 weeks or birth weights between 500 and 999 g. Cognitive function was assessed with the Wechsler Preschool and Primary Scale of Intelligence–Revised, motor function with the Movement Assessment Battery for Children, and severity of cerebral palsy with the Gross Motor Function Classification for Cerebral Palsy. Disabilities were described as mild, moderate, or severe. RESULTS: Of 371 eligible children, 306 (82%) were examined at a mean (SD) age of 5 years and 10 (4) months. For gestational age less than 28 weeks (n = 239), 26 (11%) children had cerebral palsy alone (n = 21) or in combination with blindness (n = 3) or deafness (n = 2); 1 was blind and 1 was deaf. Of the remaining children, the mean full-scale IQ was 94 ± 15, and significant predictors were (values given as the difference in IQ points [95% confidence intervals]) high maternal education (9.6 [5.7–13.4]), preeclampsia (−7.7 [−12.7 to −2.7]), and retinopathy of prematurity higher than grade 2 (−17.5 [−27.1 to −8.0]). Movement Assessment Battery for Children scores were positively associated with gestational age and prenatal steroids and negatively associated with being small for gestational age, male gender, and having retinopathy of prematurity. Moderate to severe neurodevelopmental disability was more common for gestational ages 25 weeks or less (28 of 87 children) than for 26 to 27 weeks (12 of 152 children; P < .001) and 28 weeks or more (7 of 67 children; P = .001). CONCLUSIONS: The outcome was poorer for children with gestational ages of 25 weeks or less compared with those with gestational ages between 26 and 27 weeks. For those without cerebral palsy, blindness, or deafness, however, gestational age had a limited association with cognitive and motor function.