Impact of the definition of bronchopulmonary dysplasia on neurodevelopmental outcomes

Understanding the short and long-term pulmonary and neurologic outcomes of neonates with bronchopulmonary dysplasia (BPD) is important in neonatal care for low-birth-weight infants. Different criteria for BPD may have different associations with long-term outcomes. Currently, two criteria for diagnosing BPD have been proposed by the NIH (2001) and NRN (2019) for preterm infants at a postmenstrual age (PMA) of 36 weeks. We investigated which BPD definition best predicts long-term outcomes. Korean nationwide data for preterm infants born between 24(+0) and < 32(+0) weeks gestation from January 2013 to December 2015 were collected. For long-term outcomes, severity based on the NRN criteria was significantly related to neurodevelopmental impairment (NDI) in a univariate analysis after other risk factors were controlled. For the admission rate for respiratory disorder, grade 3 BPD of the NRN criteria had the highest specificity (96%), negative predictive value (86%), and accuracy (83%). For predicting NDI at the 18–24 month follow-up, grade 3 BPD of the NRN criteria had the best specificity (98%), positive (64%) and negative (79%) predictive values, and accuracy (78%) while NIH severe BPD had the highest sensitivity (60%). The NRN definition was more strongly associated with poor 2-year developmental outcomes. BPD diagnosed by NRN definitions might better identify infants at high risk for NDI.