Healthcare resource utilization and costs in the 12 months following hospitalization for respiratory syncytial virus or unspecified bronchiolitis among infants

Aims: To examine healthcare resource utilization (HRU) and costs within 12 months after hospitalization for respiratory syncytial virus (RSVH) or unspecified bronchiolitis (UBH) in infants. Materials and methods: Infants born July 1, 2009-June 30, 2015 were identified in the MarketScan Medicaid and Commercial databases and were assigned to one of three cohorts: RSVH (with/without UBH), UBH, or comparator (no RSVH or UBH). Each infant was identified as pre-term (5 groups) or term (2 groups) based on weeks gestational age (wGA). Index dates were the first admission dates for RSVH or UBH infants and were randomly assigned to comparator infants based on time from birth to index in the RSVH cohort. HRU, all-cause costs, and incremental cost differences between hospitalized and comparator infants were assessed over 12 months post-index with and without the index hospitalization. Results were propensity score weighted to balance pre-index characteristics across hospitalization cohorts. Results: This study identified 15,872 RSVH infants, 6,081 UBH infants, and 986,087 comparator infants in the Medicaid population and 5,755 RSVH infants, 1,888 UBH infants, and 696,302 comparator infants in the commercial population. HRU in follow-up was greater for RSVH and UBH infants relative to comparator infants in both populations, including hospitalizations (commercial: 7.4%, 11.0%, 1.7%; Medicaid: 12.3%, 15.3%, 3.2%) and emergency department visits (commercial: 33.0%, 33.3%, 17.2%; Medicaid: 65.8%, 68.5%, 51.4%). HRU was highest among RSVH and UBH infants born at <29 wGA. Hospitalized infants had numerically higher follow-up costs than comparator infants, with incremental differences reaching $19,896 among Medicaid UBH infants and $37,417 among commercial RSVH infants. Limitations: RSV/UB may be miscoded in claims data. Conclusions: Infants hospitalized for RSV or UB largely had greater subsequent HRU and costs in the first year after index hospitalization than comparator infants. Absolute and incremental follow-up costs relative to comparator infants were highest among infants <29 wGA.