Neonatal respiratory dysfunction and neuropsychological performance at the preschool age: A study of very preterm infants with bronchopulmonary dysplasia.

Abstract

The neuropsychological outcome of chronic lung disease (CLD) in the very preterm (VP) infant may be determined by a process involving chronic hypoxia, with superimposed acute hypoxic episodes, in the developing brain. We wished to study the differences in quality of outcome between VP preschoolers with and without history of the most common form of CLD in the preterm infant, bronchopulmonary dysplasia (BPD). We also examined the strength of association between BPD severity and neuropsychological outcome, with degree of severity defined according to the National Institute of Child Health and Human Development (NICHD) National Heart, Lung and Blood Institute (NHLBI) Workshop categorical ranking scheme (Jobe & Bancalari, 2001) or in accord with dimensional views of severity of respiratory illness. We evaluated the intellectual, language, and motor outcomes of 156, predominantly middle-class preschoolers with history of VP birth, with (n = 80) or without (n = 76) BPD. We used supplemental oxygen requirement or need for mechanical ventilation as indirect indexes of respiratory dysfunction. Following adjustment for potentially confounding sociodemographic variables and perinatal medical risk factors, we found no group differences in neuropsychological outcome based on categorical ranking of BPD severity. However, continuous measures of BPD severity accounted for a unique portion of the variance in fine motor performance (η²p = .05), while patent ductus arteriosus, a risk marker or antecedent of BPD, explained a unique portion of the variance in both receptive language (η²p = .048), and gross motor (η²p = .061) function. A significant, yet circumscribed, association was demonstrated between neonatal hypoxic risk, in the VP infant, and neuropsychological outcome assessed in the preschool years.