LAUSR

OBJECTIVE To compare rates of hospitalizations for respiratory illnesses in preterm and full-term children for four years before and after the 2014 update to the American Academy of Pediatrics (AAP) respiratory syncytial (RSV) immunoprophylaxis guidance, which restricted eligibility among infants born at 29-34 weeks in the first winter and all preterm infants in the second winter after neonatal discharge. METHODS We conducted pre-post and interrupted time series analyses on claims data from a commercial national managed care plan. We compared the number of RSV and all respiratory hospital admissions in the first and second RSV seasons after neonatal discharge among a cohort of preterm children, regardless of palivizumab status, in the four years before and after implementation of the 2014 palivizumab eligibility change. A full-term group was included for reference. RESULTS The cohort included 821 early preterm (EP) <29 weeks, 4,790 moderate preterm (MP) 29-34 weeks, and 130,782 full-term (FT) children. Palivizumab use after the policy update decreased among MP children in the first and second RSV seasons after neonatal discharge, without any change in the odds of hospitalization with RSV or respiratory illness. For the EP group there was no change in the rate of palivizumab or the odds of hospitalization with RSV or respiratory illness after the policy update. For the FT group there was a slight decrease in odds of hospitalization post-2014 after the policy update. Interrupted time series did not reveal any secular trends over time in hospitalization rates among preterm children. Following the policy change there were cost savings for MP children in the first and second RSV seasons, when accounting for cost of hospitalizations and cost of palivizumab. CONCLUSIONS Hospitalizations for RSV or respiratory illness did not increase and cost savings were obtained after implementation of the 2014 AAP palivizumab prophylaxis policy.