Postnatal acetaminophen exposure and neurodevelopmental outcomes at 18-21 months corrected gestational age in preterm infants <29 weeks gestation: a retrospective cohort study.

BACKGROUND: Studies have reported prenatal acetaminophen exposure is associated with abnormal neurodevelopment. There is limited and conflicting data on neurodevelopmental outcomes following postnatal acetaminophen exposure. Our objective was to investigate the neurodevelopmental outcomes of preterm infants < 29 weeks gestation postnatally exposed to acetaminophen. METHODS: Retrospective cohort study of infants born between 2008 and 2017 at a tertiary care perinatal center. Exclusion criteria included chromosomal disorders, major congenital abnormalities, and congenital infections. The primary outcome was a composite score of <85 on the cognitive, language, or motor components of the Bayley Scales of Infant and Toddler Development, 3rd edition, assessed at 18 to 21 months corrected gestational age. Multivariate logistic regression was used to assess confounders. RESULTS: Of the 945 infants included in the study, 120 were in the acetaminophen group. There was no difference in any of Bayley-III cognitive, language or motor composite scores of < 85 between the two groups for postnatal acetaminophen exposure, adjusted odds ratios (aORs) 1.03, 95% CI 0.60-1.78, or days of acetaminophen use, aORs 1.10, 95% CI 0.93-1.29. CONCLUSIONS: There was no difference in neurodevelopmental outcome between the acetaminophen exposed and non-exposed groups. Our results need validation in larger cohorts. IMPACT: Animal research and cohort studies have suggested that prenatal acetaminophen exposure may be associated with an elevated risk of neurobehavioral abnormalities. However, there is limited and conflicting research on the impact of postnatal acetaminophen on neurodevelopment. The results of this study suggest that postnatal acetaminophen does not negatively impact neurodevelopment at 18 to 21 months in preterm infants born at <29 weeks gestational age. While these results need validation in larger and more longitudinal studies, this study provides reassurance for the use of postnatal acetaminophen in extremely preterm infants.