Pulmonary Surfactant Replacement Therapy for Respiratory Distress Syndrome in Neonates: a Nationwide Epidemiological Study in Korea

BACKGROUND: Pulmonary surfactant (PS) replacement therapy, as a safe and effective treatment for respiratory distress syndrome (RDS) may have further increased with the extended insurance coverage since 2011 in Korea. Thus, this study aimed to investigate the epidemiologic data of PS replacement therapy for RDS in Korea and to analyze the complications associated with RDS. METHODS: We included 19,442 infants who were treated with PS and diagnosed with RDS (International Classification of Diseases-10 codes: P22.0) between 2014 and 2018 from the Health Insurance Review and Assessment database. Birth certificate data from Statistics Korea were used to estimate the incidence of RDS. RESULTS: The average incidence of RDS within the study period was 0.99% among live births. Repeated doses of PS were administered to 1,688 infants (8.7%), ranging from 2 doses in 929 infants (4.8%) to 9 doses in 1 infant (0.01%). The incidence of RDS in term infants markedly increased over 5 years from 0.2% to 0.34%. The incidence was similarly increased among the preterm infants. The RDS mortality rate was 6.3% and showed a decreasing trend according to year. The mortality rate was significantly higher in the lower gestational age group. A decreasing trend was observed in the incidence of the complications, such as patent ductus arteriosus, intraventricular hemorrhage, and bronchopulmonary dysplasia, except for pneumothorax in term infants. The complications were also higher in the lower gestational age group and the lower birth weight group. However, pneumothorax was the most frequent complication in the term infant group and in infants with birth weight ≥ 2,500 g. CONCLUSION: Advancements in neonatal care and extended insurance coverage have increased the use of PS replacement therapy for RDS. This, in turn, decreased neonatal mortality and the incidence of the associated complications. The appropriate therapeutic strategy for RDS should be decided according to the gestational age and lung pathology.