Abstract: ［Abstract］ Objective〖HTSS〗〓To evaluate the efficacy and safety of nonvitamin K antagonist oral anticoagulants in treating venous thromboembolism.
〖HTH〗〖WTHZ〗Methods〖HTSS〗〓Data of randomized controlled trials and multicenter controlled studies about nonvitamin K antagonist oral anticoagulants versus vitamin K antagonists for treating venous thromboembolism were searched from PubMed, Cochrane Library and EMbase until June 2017, and data were analyzed by RevMan 5.3 software.
〖HTH〗〖WTHZ〗Results〖HTSS〗〓A total of 29 879 patients were included in 7 studies, Metaanalysis showed that: ① Compared with traditional vitamin K antagonists, the new oral nonvitamin K antagonist anticoagulants could significantly reduce major bleeding events （OR=0.61， 95%CI=0.50-0.75，P＜0.01） and fatal bleeding events(OR=0.37, 95%CI=0.17-0.81, P=0.01). ②nonvitamin K antagonist oral anticoagulants could not reduce the incidence of recurrent venous thromboembolism or venous thromboembolismrelated death(OR=0.94, 95%CI=0.81-0.18, P=0.38)or allcause mortality（OR=0.97，95%CI=0.83-1.13，P=0.70）compared with vitamin K antagonists. ③The results of adverse events can not be combined and analyzed，the safety superiority of nonvitamin K antagonist oral anticoagulants needs to be further evaluated.
〖HTH〗〖WTHZ〗Conclusion〖HTSS〗〓The efficacy of nonvitamin K antagonist oral anticoagulants in treating venous thromboembolism is no less than that of traditional vitamin K antagonists, and the former could reduce bleeding events significantly though their safety superiority needs to be further evaluated.

Key words: venous thromboembolism； anticoagulants; , Metaanalysis