Association of Osteoporosis-related Healthcare Costs with the Use of Tenofovir Disoproxil Fumarate and Tenofovir Alafenamide in Chronic Hepatitis B Patients: a Population-based National Cohort Study in Korea

Long-term administration of tenofovir disoproxil fumarate (TDF) for chronic hepatitis B (CHB) may lead to bone mineral density loss. Tenofovir alafenamide (TAF) developed to address these concerns. This study aimed to investigate whether there is a significant difference in osteoporosis-related healthcare costs between CHB patients treated with TDF and TAF. This study is a retrospective cohort study using claims data from the Health Insurance Review and Assessment Service (HIRA) covering the entire population in Korea. The cohort included CHB patients treated with TDF or TAF from November 2017 to April 2022. We applied inverse probability of treatment weighting (IPTW) to balance baseline characteristics observed for one-year preceding prescription date. Osteoporosis-related costs per patient per year (PPPY) included all healthcare costs with an osteoporosis diagnosis code including outpatient and hospitalization costs. 7,172 and 3,837 patients were administered TDF and TAF respectively. After IPTW, TDF group had higher outpatient costs ($11.2) compared to TAF group ($6.1), but the difference was not statistically significant (p=0.1001). The total hospitalization cost was $24.6 in TDF group and $9.8 in TAF group, not statistically significant (p=0.1633). This largescale population-based study found no significant difference in osteoporosis-related healthcare costs between CHB patients treated with TDF and TAF.