OBJECTIVES: The volume of Total Hip Arthroplasty (THA) procedures for patients with hip diseases has increased in Japan in the past decades, thus adding to the strained national socio-economic environment. However, nationwide information about patient epidemiology, medical resource utilization and cost for THA in Japan is still incomplete, because of inherent limitations of the databases analyzed. This study seeks to identify the epidemiology and economic burden of THA through evaluating a population-based claims database against published literature.

METHODS: A retrospective cohort analysis of the Japan Medical Data Center payer-based insurance claim database (JMDC) included 2783 patients ≥ 18 years old with THA (standardized procedure name=arthroplasty (hip)) between January 2009 and March 2018. For the 394 patients with more than one THA, the first procedure was selected as the index procedure for analysis. Baseline demographics, clinical characteristics, length of stay (LOS), and healthcare costs were extracted from the database. Descriptive statistics were calculated to assess the endpoints.

RESULTS: Mean (SD) age in the cohort was 56.9 (7.99) years and 23.9% of patients were male. 86% patients had a diagnosis of osteoarthritis, and the second most common diagnosis was osteonecrosis for 12.5% of patients. Mean (SD) LOS for the index hospitalization was 15.8 (7.37) days, mean (SD) total cost for the index hospitalization was ¥1,927,205 (389,375).

CONCLUSIONS: A review of relevant literature shows a range of LOS between 28.6 and 58.7 days, and total cost between ¥2,170,000 and ¥2,632,000. Despite differences in patient populations and large variabilities in data, cost of care observed was consistent with the literature. As expected, the JMDC database showed younger (34.3% patients ≥60 years old) patients undergoing THA, and shorter LOS. JMDC provides another reliable datasource, with existing literature, to better inform health policy decision-making, adding to our overall understanding of the epidemiology and economic burden of THA in Japan.