Abstract 11532: Bleeding Likelihood of Apixaban in Primary VTE Prophylaxis: A Meta-Analysis
Introduction: The American College of Physician recommends pharmacologic prophylaxis with heparin or a related drug for venous thromboembolism (VTE) in hospitalized patients unless the assessed risk for bleeding outweighs benefits. Apixaban is an orally active, selective, and direct inhibitor of factor Xa, approved for VTE prevention outside United States. The purpose of this meta-analysis was to compare the efficacy and safety of apixaban versus enoxaparin.
Hypothesis: The rate of bleeding events in patients receiving apixaban is lower than those receiving LMWH for VTE prophylaxis.
Methods: We performed a comprehensive search in PubMed, Cochrane Library, MEDLINE, EMBASE, and abstracts presented at national meetings. Two reviewers abstracted all the information and a tie breaker resolved discrepancies. We used R (R Meta package v 0.8-2) for analysis. The odds ratio (OR) with 95% confidence intervals (CI) were calculated using random effect model by DerSimonian and Liard.
Results: We reviewed a total of 406 abstracts of which 148 studies were selected for full review. We abstracted for analysis 5 studies involving 12,867 patients (apixaban, n=6,448; LMWH, n=6,419). VTE prophylaxis was given after total knee replacement in 3 studies, total hip replacement in 1 study, and to acutely ill medical patients in 1 study. Heterogeneity among the studies precluded a pooled analysis of bleeding likelihood; however, apixaban was associated with lower bleeding events than LMWH when used after total knee replacement (OR=0.55, 95% CI 0.31-0.95;I2=0; p=0.58). Based on pooled estimate across the studies, apixaban was not better than LMWH in preventing pulmonary embolism (OR=1.19, 95% CI 0.51-2.76; I2=38.8%; p=0.16).
Conclusion: In the setting of total knee replacement, apixaban is associated with a lower incidence of bleeding. The superiority of apixaban in primary prevention of PE is not yet proven.
- © 2013 by American Heart Association, Inc.