Apixaban versus enoxaparin for thromboprophylaxis after total hip or knee arthroplasty: a meta-analysis of randomized controlled trials.

BACKGROUND: Enoxaparin is routinely used for prevention of venous thromboembolism (VTE) after total hip or knee arthroplasty. The purpose of this study was to compare the efficacy and safety of apixaban, a newly oral direct inhibitor of factor Xa versus enoxaparin. METHODS: We performed a meta-analysis of relevant randomized-controlled trials (RCTs) identified in PubMed, Cochrane Library, Embase China Biological Medical Literature database, Countries Journal full-text database, VIP database, and WanFang database. The primary efficacy outcome for our meta-analysis was all VTE and all-cause mortality. The secondary efficacy outcomes included major VTE, non-fatal pulmonary embolism, and mortality. The primary safety outcome was bleeding events, categorized as major, clinically relevant non-major, or minor events. RESULTS: Four RCTs, involving 14 065 patients, were included in our meta-analysis. Compared to enoxaparin, thromboprophylaxis with apixaban was associated with significantly fewer VTE and all-cause mortality (8346 patients, risk ratio (RR): 0.63, 95%CI 0.42 - 0.95) and similar incidence of bleeding events (major bleeding, 11 525 patients, RR 0.76, 95%CI 0.43 - 1.33; clinically relevant non-major bleeding, 11 525 patients, RR 0.83, 95%CI 0.69 - 1.01; and minor bleeding, 11 828 patients, RR 0.93, 95%CI 0.79 - 1.09). However, our meta-analysis revealed similar effects of apixaban with enoxaparin for thromboprophylaxis with regard to the secondary efficacy outcomes. CONCLUSIONS: Apixaban was more effective than recommended dose of enoxaparin and had a similar safety profile for thromboprophylaxis after hip and knee arthroplasty. But more evidence, especially well designed head-to-head RCTs, is needed to confirm the superior efficacy of apixaban.