Impact of Demographics and Social Determinants of Health on Hospitalization Costs in US Adults With Respiratory Syncytial Virus

OBJECTIVES: Characterize the impact of demographics and social determinants of health (SDOH) on healthcare expenditures among insured adults hospitalized with Respiratory Syncytial Virus (RSV).

METHODS: This retrospective study identified US adults aged ≥18 years with an RSV ICD-10 diagnosis between July 1, 2016, and June 30, 2019, stratified by RSV season using Inovalon’s closed claims database linked to SDOH characteristics from the Acxiom’s Market Indices data. Area-based SDOH data were identified via a ZIP9 code linkage. RSV episodes were defined as an index diagnosis date to a final claim date, with a new episode defined by at least a 90-day claim-free interval. Analysis focused on the first RSV episode of each season, demographics, and SDOH for RSV inpatient visits. The descriptive evaluation included length of stay (LOS), inpatient costs standardized to Medicare costs, and adjustment to 2022 values.

RESULTS: Across three RSV seasons, 5,757; 7,472; and 9,094 RSV patients were assessed, respectively, with an average age of 49 years and Charlson Comorbidity Index of 2.0. The distribution of payer type was 58% Commercial, 24% Medicaid, and 18% Medicare Advantage. RSV-related hospitalizations occurred in 10.4% (n=602), 15.8% (n=1,184), and 13.7% (n=1,246) of patients in each respective year. The average unadjusted RSV-related inpatient cost per episode was $11,523, $11,912, and $11,362, with mean LOS of 7.7, 8.3, and 8.2 days respectively. There were no statistically significant differences in RSV-related inpatient costs between the adult age groups of <60 and ≥60 years. The highest RSV-related inpatient costs were observed in males, Asians, or individuals residing in neighborhoods with SDOH designations as full primary care shortage areas, lower college attainment, or lower English proficiency.

CONCLUSIONS: Adults hospitalized with RSV incur 7-8 days stay with high episode costs. Certain sub-populations incur higher costs that may reflect healthcare disparities related to healthcare system navigation and other factors.