Perinatal factors associated with bubbly/cystic appearance in bronchopulmonary dysplasia: a nationwide, population-based cohort study in Japan

Bronchopulmonary dysplasia (BPD) remains one of the most serious morbidities associated with preterm birth. Previous study reported that bubbly/cystic appearance on chest X-rays in the neonatal period is the strongest determinant of impaired lung function at school age in BPD patients. To determine perinatal risk factors for bubbly/cystic appearance on chest X-rays in extremely premature infants with BPD exposed to histological chorioamnionitis histological chorioamnionitis (hCAM). Multicenter retrospective cohort study. We analyzed 1369 extremely premature infants with severe hCAM who were admitted to the neonatal intensive care units participating in the Neonatal Research Network, Japan (NRNJ) Neonatal research network Japan. Perinatal characteristics were compared and logistic regression analysis was performed for multivariate risk factor assessment. Infants with bubbly/cystic appearance on chest X-rays underwent longer duration of invasive mechanical ventilation and required inhaled nitric oxide and home oxygen therapy more frequently. Low gestational age (odds ratio 1.244; 95% confidence interval 1.139–1.359) and preterm premature rupture of membranes (odds ratio 1.507; 95% confidence interval 1.200–1.893) were significant risk factors. Low gestational age and preterm premature rupture of membranes were independent risk factors for bubbly/cystic appearance in extremely premature infants with BPD following exposure to severe hCAM.