Limited research exists on the economic impact of respiratory syncytial virus lower respiratory infection (RSV LRI) among vulnerable infant populations. This study evaluated healthcare costs of full-term and late-preterm Medicaid infants with RSV LRI within 1 year of infection. Medicaid administrative claims were used to conduct a retrospective study of infants born 2003-2005. Full-term and late-preterm infants <1 year old were assigned to groups based on RSV LRI and unspecified bronchiolitis/pneumonia (UBP) diagnosis codes and stratified by setting of diagnosis. Infants without evidence of RSV LRI/UBP were selected as a comparison group. Economic and clinical outcomes were analyzed descriptively using propensity score weighting, and logged ordinary least squares models were used to examine relationship between RSV and costs incurred within 1 year of infection. RSV LRI and UBP infants, regardless of gestational age or healthcare setting, were more likely to experience respiratory diagnoses of wheezing and infantile asthma versus comparisons. Adjusted and weighted healthcare costs were significantly higher for all groups of RSV LRI and UBP infants relative to comparison infants (P < 0.001). Among late-preterm infants with inpatient and outpatient RSV, marginal costs compared with controls were $17,465 and $2,158, respectively. Costs for RSV LRI and UBP Medicaid infants are substantial. While much of the costs result from initial RSV episodes, higher post-episode costs and rates of respiratory events, procedures, and medications in RSV and UBP infants versus comparisons indicate long-term economic impact from infection and the impact is greater among late-preterm compared to full-term infants.
Copyright 2010 Wiley-Liss, Inc.