Abstract
BACKGROUND: Hip or knee joint replacement (HJR or KJR) is linked to a short-term increased risk of venous thromboembolism (VTE), but evidence on long-term VTE risk beyond 1 year is limited. This study compared the 10-year VTE risk in HJR or KJR patients with the general population. METHODS: We conducted a prospective matched cohort study using the UK Biobank. A total of 18,984 HJR and 16,709 KJR patients were matched with controls by age, sex, VTE history, and cancer history via exposure density sampling. Flexible parametric models and piecewise Cox models were used to estimate time-varying hazard ratios (HRs) and 95% confidence intervals (CIs) for VTE over 10 years postsurgery. RESULTS: A total of 211,190 participants were included in the HJR cohort and 192,440 in the KJR cohort. The 10-year VTE risk was 6.2% (95% CI, 5.7%-6.7%) for HJR and 7.5% (95% CI, 7.0%-8.0%) for KJR. VTE risk peaked immediately postsurgery, declined gradually, but remained elevated throughout the 10-year follow-up. For HJR, the HR decreased from 24.10 (95% CI, 16.93-34.30) in the first 30 days to 1.49 (95% CI, 1.17-1.90) in years 8 to 10. For KJR, it decreased from 27.31 (95% CI, 19.67-37.92) to 1.32 (95% CI, 1.04-1.68) over the same period. CONCLUSION: VTE risk rises sharply after HJR or KJR and remains elevated for 10 years. Further studies should extend follow-up and collect detailed covariates related to VTE events to validate and characterize the potential long-term risk associated with HJR or KJR.