The impact of chorioamnionitis on neurodevelopmental outcomes at 3, 8 and 18 years in low-birthweight preterm infants

OBJECTIVE: To assess the long-term cognitive, behavioral and academic status of preterm children exposed to clinical chorioamnionitis. STUDY DESIGN: In total, 985 infants (<37 weeks and 2500 g at birth) were recruited in a multisite interventional research program. Of these, 43 case-infants were identified based on documented diagnosis of maternal clinical chorioamnionitis. Infants with chorioamnionitis were compared with the remainder of the cohort after controlling for maternal and infant variables. All infants underwent cognitive, behavioral and academic achievement assessments at 3, 8 and 18 years. Standardized cognitive and academic achievement scores were cutoff at 2 s.d.'s below the mean, behavioral scores were cutoff at a T-score >70 and examined with chi(2) statistics. Mean scores were evaluated using preliminary bivariate analysis and were followed by multiple regression models predicting child outcomes. RESULT: Overall, children with chorioamnionitis did not have lower scores on any assessment at any age. Children without chorioamnionitis performed significantly lower at 8 years on the Woodcock-Johnson reading subscore and the mean score of the Peabody Picture Vocabulary Test (PPVT). No significant difference persisted to 18-year follow-up. In logistic regression, chorioamnionitis independently predicted higher PPVT scores at 8 years, but not lower performance scores on the Woodcock-Johnson reading subscore. CONCLUSION: Clinical chorioamnionitis was not associated with adverse neurodevelopmental outcomes in this group of preterm infants <37 weeks and 2500 g.