Respiratory Syncytial Virus and All-Cause Bronchiolitis Hospitalizations among Preterm Infants Using the Pediatric Health Information System (PHIS).

Background In 2014, the American Academy of Pediatrics stopped recommending palivizumab to otherwise healthy 29-34 weeks' gestational age (wGA) infants aged <12 months at respiratory syncytial virus (RSV) season start. Here, we compare the burden of RSV hospitalizations (RSVH) and all-cause bronchiolitis hospitalizations (BH) before and after 2014 among otherwise healthy 29-34 wGA infants hospitalized at <= 6 months of age. Methods A historical, observational cohort study was conducted to evaluate RSVH and BH in 29-34 wGA infants during the 2010-2017 RSV seasons using encounter data from 51 United States children's hospitals that comprise the Pediatric Health Information System. Results The overall cohort included 67 570 RSVH out of 96 281 patients with BH. wGA was known for 22 937 RSVH and 33 289 BH. For 29-34 wGA infants, there were 8.7% and 14.2% RSVH before and after 2014, respectively (P < .0001). Intensive care unit admissions increased for RSVH (from 54.5% to 64.2%; P = .0002) and BH (from 46.7% to 54.5%; P = .0005) after controlling for sex, race, comorbidity, and cluster. The total cost of care increased for RSVH from $37 million to nearly $60 million. Conclusions RSVH, BH, and their severity increased among 29-34 wGA infants in the 3 RSV seasons following 2014. This historical, observational cohort study demonstrates that respiratory syncytial virus (RSV) hospitalizations and all-cause bronchiolitis hospitalizations and their severity increased among otherwise healthy 29-34 weeks' gestational age infants aged <6 months in the 2014-2017 vs 2010-2014 RSV seasons.