Table of Contents
Volume 2010, Article ID 540386, 9 pages
Clinical Study

Different Finite Durations of Anticoagulation and Outcomes following Idiopathic Venous Thromboembolism: A Meta-Analysis

1Department of Pulmonary/Critical Care/Sleep Medicine, Walter Reed Army Medical Center, Pulmonary/Sleep and Critical Care Service, 6900 Georgia Avenue NW, Washington, DC 20307, USA
2Department of Pulmonary/Critical Care Medicine, William Beaumont Army Medical Center, 5005 N. Piedras Street, El Paso, TX 79930, USA
3Department of Medicine, The Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd, Bethesda, MD 20814, USA

Received 4 October 2010; Accepted 15 November 2010

Academic Editor: Paolo Simioni

Copyright © 2010 Aaron B. Holley et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Introduction. Controversy remains over the optimal length of anticoagulation following idiopathic venous thromboembolism. We sought to determine if a longer, finite course of anticoagulation offered additional benefit over a short course in the initial treatment of the first episode of idiopathic venous thromboembolism. Data Extraction. Rates of deep venous thrombosis, pulmonary embolism, combined venous thromboembolism, major bleeding, and mortality were extracted from prospective trials enrolling patients with first time, idiopathic venous thromboembolism. Data was pooled using random effects meta-regression. Results. Ten trials, with a total of 3225 patients, met inclusion criteria. For each additional month of initial anticoagulation, once therapy was stopped, recurrent venous thromboembolism (0.03 (95% CI: −0.28 to 0.35); 𝑃 = . 2 4 ), mortality (−0.10 (95% CI: −0.24 to 0.04); 𝑃 = . 1 5 ), and major bleeding (−0.01 (95% CI: −0.05 to 0.02); 𝑃 = . 4 4 ) rates measured in percent per patient years, did not significantly change. Conclusions: Patients with an initial idiopathic venous thromboembolism should be treated with 3 to 6 months of secondary prophylaxis with vitamin K antagonists. At that time, a decision between continuing with indefinite therapy can be made, but there is no benefit to a longer (but finite) course of therapy.