Developmental Outcome of Very-Low-Birth-Weight Infants without Major Brain Injuries Based on Data from the Korean Neonatal Network: A Nationwide Cohort Study

Abstract

Purpose: As preterm infants have shown advances in survival rate, many very-low-birth-weight (VLBW) infants have shown developmental delay even without a major brain injury. Thus, the incidence of and risk factors associated with poor neurodevelopmental outcome should be evaluated. Methods: A multicenter nationwide prospective longitudinal cohort study of VLBW infants born in South Korea between 2013 and 2015 was conducted. Poor neurodevelopmental outcome was diagnosed if the Bayley Scales of Infant and Toddler Development (BSID)-III composite score was ≤85 (cognition, language, motor). We analyzed the associations of baseline neonatal characteristics, environmental characteristics and neonatal morbidities with poor neurodevelopmental outcome. Results: The study included 285 infants, of whom 34 (11.9%) exhibited cognition delay; 59 (20.7%), showed language delay and 32 (11.2%) showed motor delay. The mean gestational age and birth weight were 29 weeks and 1,130 g, respectively. Moderate and severe bronchopulmonary dysplasia (P=0.056) and intraventricular hemorrhage grade I (P=0.079) were marginally associated with cognition delay. Higher paternal educational level (P<0.05) was significantly associated with the language outcome. Birth weight (P<0.05) and head circumference at discharge (P<0.05) were the major predictors of motor delay. Conclusion: The population-based nationwide cohort study shows that approximately 20% of VLBW infants without major brain injury have developmental delay. Several factors that are not directly associated with major brain injury were significantly associated with poor neurodevelopmental outcome.