Reduced dose direct oral anticoagulants in the extended treatment of venous thromboembolism: a systematic review and meta-analysis.
J Thromb Haemost. 2018 May 17;:
Authors: Vasanthamohan L, Boonyawat K, Chai-Adisakopha C, Crowther M
BACKGROUND: Extended duration anticoagulation is beneficial for preventing recurrent venous thromboembolism (VTE). Reduced dose direct oral anticoagulants (DOACs) may be preferable if they preserve efficacy and cause less bleeding. We conducted a systematic review and meta-analysis of trials comparing reduced dose DOACs with full dose DOACs and aspirin or placebo in the extended phase of VTE treatment.
METHODS: A literature search was conducted using the MEDLINE, EMBASE and CINAHL databases supplemented by hand-searching. 1399 titles were screened, with data from accepted studies extracted by two independent reviewers. Major outcomes analyzed included recurrent VTE as well as events of major and clinically relevant nonmajor bleeding, using risk ratios (RR) and 95% confidence intervals (CI).
RESULTS: Two trials met pre-specified inclusion criteria. Data from 5847 patients was analyzed for efficacy outcomes and from 5842 patients for safety outcomes. Reduced dose DOACs were as effective as full dose treatment for preventing recurrent VTE at one year (RR 1.12 [95% CI 0.67-1.87]), and more effective than aspirin or placebo (RR 0.26 [95% CI 0.14-0.46]). Major or clinically relevant nonmajor bleeding events were similar between reduced dose DOACs and aspirin or placebo (RR 1.19 [95% CI 0.81-1.77]). There was a trend towards less bleeding when reduced and full dose DOACs were compared (RR 0.74 [95% CI 0.52-1.05]).
CONCLUSIONS: Extended duration treatment of VTE with reduced dose DOAC may be as efficacious as full dose treatment, with rates of major bleeding similar to treatment with aspirin or placebo, but further long-term studies are needed. This article is protected by copyright. All rights reserved.
PMID: 29772108 [PubMed - as supplied by publisher]