More bronchopulmonary dysplasia with improved survival in extremely preterm infants

초록

Objective Although advances in neonatal intensive care have significantly reduced mortality in preterm infants, the incidence of bronchopulmonary dysplasia (BPD) is increasing. This study evaluated mortality, BPD, and the combined incidence of BPD or mortality among extremely preterm infants in Korea. Methods We analyzed extremely preterm infants with gestational ages of 23-27 weeks, born between January 1, 2014, and December 31, 2021, using data from the Korean Neonatal Network, a large nationwide cohort of preterm infants in Korea. BPD was diagnosed at 36 weeks' postmenstrual age based on the 2019 Neonatal Research Network definition. Trends in mortality, BPD incidence, and associated risk factors were assessed from 2014 to 2021. Results The mean gestational age was 25.7 ± 1.2 weeks, and the mean birth weight was 870.7 ± 194.2 grams. The incidence of BPD among survivors increased from 51.2% in 2014 to 62.7% in 2021 (P < 0.001), while mortality decreased from 28.3% to 19.5% (P < 0.001). The combined incidence of BPD or mortality also increased, from 63.6% in 2014 to 66.9% in 2021 (P = 0.006). Although the duration of invasive ventilation, the incidence of endotracheal intubation at birth, and intubation for surfactant administration decreased, the duration of non-invasive ventilation and ventilatory support increased. Conclusion Although the mortality decreased, the incidence of BPD and the combined incidence of BPD or mortality increased, likely due to the longer duration of ventilatory support. This suggests a trade-off between improved survival and an increased incidence of BPD among survivors.