Aspirin for venous thromboembolism prophylaxis after hip or knee arthroplasty: An updated meta-analysis of randomized controlled trials.

BACKGROUND: Patients who undergo knee or hip arthroplasty are at a significant risk of venous thromboembolism (VTE) development (pulmonary embolism and/or deep-vein thrombosis). Many different thromboprophylactic strategies have been used for the prevention of VTE in these patients with different outcomes. Therefore, our aim was to evaluate the efficacy and safety of aspirin prophylaxis when compared with placebo or anticoagulants in this population of patients.

METHODS: A comprehensive electronic database search was conducted for all randomized controlled trials (RCTs) comparing the clinical outcomes of aspirin versus placebo or anticoagulants for the prevention of VTE after knee or hip arthroplasty. The primary outcome was VTE incidence. Secondary outcomes included any bleeding, major bleeding and mortality. We calculated risk ratios (RRs) and 95% confidence intervals (CIs) using a random-effects model at the longest possible follow-up period.

RESULTS: We included 13 RCTs with a total of 20,115 patients with a mean age of 67.15 ± 9.54 and 24.39% males. Aspirin was found to be associated with a non-significantly reduced VTE events compared with other thromboprophylactic methods (RR 0.87; 95% CI: 0.61-1.23; P = 0.43). Compared with placebo, aspirin was associated with significant reduction of VTE (RR 0.65; 95% CI: 0.47-0.89; P = 0.008). There were no significant differences in the clinical outcomes between all groups with regard to mortality (RR 0.98; 95% CI: 0.86-1.11; P = 0.72), major bleeding events (RR 0.96; 95% CI: 0.50-1.84; P = 0.91), and any bleeding events (RR: 1.09; 95% CI: 0.82-1.44; P = 0.56).

CONCLUSION: Among patients who underwent knee or hip arthroplasty, aspirin prophylaxis was found to be associated with similar efficacy and safety outcomes when compared with anticoagulants. When compared with placebo, aspirin prophylaxis was associated with significantly reduced VTE and a comparable safety profile.