Trends in epidemiology and outcomes of respiratory distress syndrome in the United States

Background: The management practices of Respiratory Distress Syndrome (RDS) in the newborn have changed over time. We examine the trends in the epidemiology, resource utilization, and outcomes (mortality and bronchopulmonary dysplasia [BPD]) of RDS in preterm neonates ≤34 weeks gestational age (GA) in the United States. Methods: In this retrospective serial cross-sectional study, we used ICD-9 codes to classify preterm infants GA ≤34 weeks between 2003 and 2014 from the National Inpatient Sample as having RDS or not. Trends in the prevalence of infants defined as RDS by ICD-9 code (ICD9-RDS), length of stay, BPD, and mortality were analyzed using Cochran-Armitage and Jonckheere-Terpstra tests and multivariable logistic regression. Results: Of 1 526 186 preterm live births with GA ≤34 weeks, 554 409 had ICD9-RDS (260 cases per 1000 live births) with the prevalence increasing from 170 to 361 (P _trend < 0.001) and associated decrease in all-cause mortality (7.6% to 6.1%; P _trend < 0.001) from 2003 to 2014. Increased utilization of non-invasive mechanical ventilation (NIMV) (69.5% to 74.3%; P _trend < 0.001) was associated with decreased invasive mechanical ventilation (IMV) use >96 h (60.4 to 56.6%; P _trend < 0.001). Exclusive NIMV use increased from 16.8% to 29.1% (P _trend < 0.0001). BPD incidence decreased from 14% to 12.5% (P _trend < 0.001). LOS increased from 32 days to 38 days (P _trend < 0.001) and cost increased from $49,521 to $55,394 (P _trend < 0.001). Conclusion: From 2003 to 2014, the assigned ICD9-RDS diagnosis, and utilization of NIMV increased and mortality among infants assigned the ICD9-RDS diagnosis decreased. With higher survival, hospital cost increased incrementally, indicating the importance of ongoing analysis of appropriate reimbursement for the care provided at tertiary centers for preterm infants.