Respiratory syncytial virus and premature infants born at 32 weeks' gestation or earlier - Hospitalization and economic implications of prophylaxis

Objectives: To assess the risk of hospitalization associated with respirato ry syncytial virus (RSV) and, to estimate the economic impact of RSV prophy laxis with either RSV immune globulin (RSV-Ig) or RSV monoclonal antibody ( palivizumab) on a cohort of preterm infants born at 32 weeks' gestation or earlier. Design: Historical cohort study. Setting: A 12-county neonatal network served by the regional center in Roch ester, NY. Participants: One thousand twenty-nine infants born at 32 weeks' gestation or earlier followed up until 1 year of corrected age. Main Outcome Measures: Rate of hospitalization with an RSV-associated illne ss; cost per hospitalization prevented resulting from either form of RSV pr ophylaxis. Results: The probability of hospitalization with an RSV-associated illness for infants born at 32 weeks' gestation or earlier was estimated at 11.2%. The incidence of RSV hospitalization increased with decreasing gestational age (13.9% vs 4.4% for infants born at less than or equal to 26 weeks' gest ation vs those born at 30-32 weeks' gestation). Infants requiring respirato ry support at 36 weeks of postconceptual age (PCA) or older had a higher ho spitalization rate (16.8% vs 6.2%), longer hospital stays, and higher hospi tal charges than infants requiring respiratory support at less than 36 week s of PCA. For infants requiring respiratory support at less than 36 weeks o f PCA, the incidence of RSV hospitalization still increased with decreasing gestational age (10.2% vs 4.3% for infants less than or equal to 26 weeks' gestation vs those 30-32 weeks' gestation). Analysis indicated that both f orms of RSV prophylaxis would increase the net cost of care for all groups. Palivizumab was more cost-effective than RSV-Ig for preventing RSV hospita lization among infants who required respiratory support at less than 36 wee ks of PCA, especially those born at 26 weeks' gestation or earlier. Overall , RSV-Ig was more cost-effective than palivizumab for infants requiring res piratory support at 36 weeks of PCA or older. Conclusions: This analysis suggests that available forms of RSV prophylaxis would increase the net cost of care not only for the entire cohort but for each of the subgroups studied. However, the RSV hospitalization rate and t he cost-effectiveness of prophylaxis varied markedly by subgroup.