Health and Economic Burden of Severe Respiratory Syncytial Virus Infections Among Older Adults in Japan: A Retrospective Administrative Database Study

Respiratory syncytial virus (RSV) is a leading cause of acute respiratory illness and severe outcomes in older adults. This retrospective cohort study investigated the health and economic burden of medically attended RSV infections among adults ≥ 60 years in Japan. Data were collected between 1 September 2008 and 31 August 2021 from the Medical Data Vision (MDV) hospital-based claims database and the insurance-based JMDC database. We investigated RSV-related complications during the first episode. Healthcare resource utilization (HCRU) and medical costs were compared between baseline (pre-event: 30-day average costs during the 365 days before RSV diagnosis) and post-event (30 days after RSV diagnosis); differences were explored using paired sample t -tests ( p < 0.05). A total of 178 cases identified between 2009 and 2019 were included in the study, 144 were from the MDV database (mean age 74 years) and 34 from the JMDC database (mean age 64 years). RSV-related complications were recorded in 61.1% and 55.9% of the MDV and JMDC cohorts, respectively. HCRU in the MDV cohort increased significantly from pre- to post-event (average number of outpatient visits per case: 1.21 to 2.07; average number of hospitalizations per case: 0.07 to 0.37), resulting in significant additional medical costs of ¥196,231 ( p < 0.001). Medically attended RSV infections were associated with substantial short-term increases in HCRU and total medical costs among older adults in Japan. These findings may help inform prevention strategies for severe RSV disease.