Direct oral anticoagulants in the treatment of acute venous thromboembolism: A systematic review and meta-analysis

Acute venous thromboembolism (VTE) is a common disease associated to significant morbidity and mortality.We systematically reviewed and meta-analysed clinical outcomes with direct oral anticoagulants (DOAC: dabigatran, rivaroxaban, apixaban or edoxaban) for treatment of acute VTE. We used MEDLINE and CENTRAL, clinical trials registers, conference proceedings, and websites of regulatory agencies to identify randomised clinical trials of DOAC compared with conventional treatment [parenteral anticoagulant followed by a vitamin K antagonist (VKA)] for acute VTE. Two investigators independently extracted data. Relative risk of recurrent VTE, bleeding events, deaths and a net clinical endpoint (composite of recurrent VTE, major bleeding, and death) were estimated using a random effect meta-analysis (RevMan software).Six trials including 27,127 patients were selected. The risk of recurrent VTE was similar with the DOAC and standard treatment (relative risk 0.91, 95% confidence interval 0.79 to 1.06). The DOAC reduced the risk of major bleeding in comparison with standard treatment (0.62, 0.45 to 0.85) (absolute risk difference, -0.6%; 95% confidence interval -1.0% to -0.3%), but there was heterogeneity across trials in the relative risk of bleeding. No between treatment differences were found in the relative risk of all-cause mortality (0.98, 0.84 to 1.14). The DOAC and conventional treatment differed on the net clinical endpoint (0.85, 0.75 to 0.97). Subgroup analyses in relevant subgroups (index pulmonary embolism, heparin lead-in, age, gender, renal function, presence of cancer), as well as sensitivity analyses, were consistent with the main analysis.The DOAC seem as effective as, and probably safer than standard treatment of acute VTE. The relative efficacy and safety of the DOAC was consistent across a wide range of patients.