Incidence of bronchopulmonary dysplasia in Korea.

A nationwide survey was conducted to determine the incidence of bronchopulmonary dysplasia (BPD) in Korea and the intercenter differences in survival and BPD rates among preterm infants. Questionnaires were sent to all registered neonatal intensive care units (NICUs). The questionnaires inquired about the survival and BPD rates of very low birth weight (VLBW, < 1,500 g) infants who had been admitted to each NICU from 2007 to 2008. BPD was defined as requiring oxygen at 36 weeks' postmenstrual age. Almost all level III NICUs replied. During the study period, 3,841 VLBW infants were born in the NICUs that responded to the survey. The survival rate was 81% and the BPD rate was 18%. Combined outcome of BPD or death rate was 37%. The BPD rate and combined outcome of BPD or death rate varied considerably from 5% to 50% and 11% to 73%, respectively across the centers. There was no significant correlation between the survival rate and the BPD rate across the centers. In conclusion, the incidence of BPD among VLBW infants in Korea during the study period was 18%, and a considerable intercenter difference in BPD rates was noted.