Effects of anti-osteoporosis medications on total hip arthroplasty risks in osteoporotic patients with hip osteoarthritis in Taiwan: a nationwide cohort study

A Summary This nationwide cohort study examined the potential disease-modifying effect of anti-osteoporosis medication on hip osteoarthritis. The results revealed that the usage of anti-osteoporosis medication is not associated with decreased risk in undergoing total hip arthroplasty in patient with hip osteoarthritis. Purpose This study aimed to assess the association between use of anti-osteoporosis medications (AOMs) and the risk of undergoing total hip arthroplasty (THA) in patients with hip osteoarthritis (OA). Methods Using the 2008-2013 National Health Insurance Research Database, we identified patients who were first diagnosed as having hip OA. All identified patients were followed until THA, death of any cause, or December 31, 2013, whichever occurred first. All AOM exposures were divided into three categories: bisphosphonates use, non-bisphosphonates use, and no use of AOMs and assessed in a time-varying manners. The primary outcome was THA. The secondary outcome was the differences in the longitudinal utilization of NSAIDs between AOM users and non-users. Time-dependent Cox proportional hazards models were used to investigate the effect of AOM use on the risk of THA. Results We identified 35,870 patients who were first diagnosed as having hip OA and had no history of AOM use between 2009 and 2012. Among them, 3162 and 1667 patients had their first prescription of bisphosphonates and other non-bisphosphonates AOMs during the follow-up period. Mean age of bisphosphonates users, non-bisphosphonates users, and non-users was 75.62, 76.84, and 67.39 years, respectively. Bisphosphonates or non-bisphosphonates users did not show significant change when compared to non-users in terms of risk of undergoing THA [adjusted hazard ratio (aHR) 0.972, 95% confidence interval (CI) 0.743-1.273; aHR 0.926, 95% CI 0.672-1.277]. Conclusion Our results showed that the use of AOMs is not associated with decreased risk of THA in patients with hip OA.