Abstract
OBJECTIVE: This systematic review and meta-analysis aimed to evaluate the risk of all-cause mortality in patients with knee osteoarthritis (OA). DESIGN: Comprehensive searches were conducted in PubMed, Embase, and the Cochrane Library on September 01, 2024. The review included cohort studies reporting risk estimates of all-cause mortality in knee OA patients compared to those without knee OA. Using a random-effects model, the pooled hazard ratios (HRs) were calculated. Subgroup analyses were performed according to the classification of knee OA, including radiographic knee OA only, symptomatic knee OA only, and radiographic and symptomatic knee OA. RESULTS: A total of 15 cohort studies involving 1,023,799 participants were included in the systematic review, with 14 studies remaining for the meta-analysis. The meta-analysis revealed that knee OA patients had an increased risk of all-cause mortality compared to those without knee OA (pooled HR: 1.21; 95% confidence interval [CI]: 1.02, 1.45). Subgroup analyses indicated the mixed results, including radiographic knee OA only (pooled HR: 1.11; 95% CI: 0.97, 1.26), symptomatic knee OA only (pooled HR: 1.07; 95% CI: 0.80, 1.43), and radiographic and symptomatic knee OA (pooled HR: 1.58; 95% CI: 1.20, 2.07). CONCLUSIONS: This meta-analysis supports an association between knee OA and an increased risk of all-cause mortality, with a particularly pronounced risk observed in radiographic and symptomatic knee OA patients. Further research is needed to determine if OA at other sites also correlates with a higher risk of all-cause mortality.