Bronchopulmonary Dysplasia Definitions As Predictors of Early Childhood Pulmonary Function

To assess the clinical utility and predictive ability of three commonly used definitions of bronchopulmonary dysplasia (BPD) (2001 NHLBI, 2018 NICHD, 2019 NRN) in forecasting lung function outcomes in children with a history of prematurity and BPD.

A retrospective chart review of 138 children with a history of prematurity and BPD who were recruited from two outpatient clinics at large tertiary medical centers was performed. Each subject's lung disease was classified based on the three definitions of BPD. Regression analyses were performed to assess the association between lung function (FEV1%predicted, FVC %predicted) and BPD status, defined dichotomously and by severity. Additional analyses compared lung function outcomes by need for supplemental oxygen at hospital discharge and history of pulmonary hypertension.

None of the three definitions evaluated met the criteria for an ideal definition that can both identify individuals at risk for long-term pulmonary impairment and stratify disease severity in a clinically meaningful way. In dichotomized analysis (BPD vs. no BPD), both the 2018 NICHD and 2019 NRN definitions identified preterm-born individuals with significantly lower lung function parameters compared to preterm-born individuals without BPD whereas the 2001 NHLBI definition failed to distinguish between affected and unaffected individuals. A clear gradient of worsening lung function with increasing BPD severity was appreciated using the 2001 NHLBI criteria, highlighting an aspect of the definition's relative strength in stratifying long-term risk.

Newer definitions of BPD (2018 NICHD, 2019 NRN) more effectively identify children at risk for impaired pulmonary function than the older NHLBI definition. The association of supplemental oxygen requirement and diagnosis of pulmonary hypertension with lung function parameters suggests that there may be clinical indicators that are more predictive of long-term respiratory outcomes than the currently available definitions. There continues to be a need for significant refinement in the definition of BPD to improve its predictive value and guide long-term management strategies.