Objective: This article aims to compare respiratory syncytial virus (RSV) immunoprophylaxis (IP) use and RSV hospitalization rates (RSVH) in preterm and full-term infants without chronic lung disease of prematurity or congenital heart disease before and after the recommendation against RSV IP use in preterm infants born at 29 to 34 weeks' gestational age (wGA).
Study design: Infants in commercial and Medicaid claims databases were followed from birth through first year to assess RSV IP and RSVH, as a function of infant's age and wGA. RSV IP was based on pharmacy or outpatient medical claims for palivizumab. RSVH was based on inpatient medical claims with a diagnosis of RSV.
Results: Commercial and Medicaid infants 29 to 34 wGA represented 2.9 to 3.5% of all births. RSV IP use in infants 29 to 34 wGA decreased 62 to 95% (p < 0.01) in the 2014-2015 season relative to the 2013-2014 season. Compared with the 2013-2014 season, RSVH increased by 2.7-fold (p = 0.02) and 1.4-fold (p = 0.03) for infants aged <3 months and 29 to 34 wGA in the 2014-2015 season with commercial and Medicaid insurance, respectively. In the 2014-2015 season, RSVH for infants 29 to 34 wGA were two to seven times higher than full-term infants without high-risk conditions.
Conclusion: Following the 2014 RSV IP guidance change, RSV IP use declined and RSVH increased among infants born at 29 to 34 wGA and aged <3 months.
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.