Extended Treatment of Venous Thromboembolism

Patients with provoked venous thromboembolism caused by transient risk factors can generally stop anticoagulation after 3 months of treatment. For patients with unprovoked venous thromboembolism, for which the risk of recurrence is as high as 40% at 5 years,1 it may be appropriate to consider a longer course of therapy. However, deciding how to balance the risks and benefits of extended anticoagulation is difficult. Warfarin has greater than 90% efficacy in preventing recurrences but carries an associated risk of major bleeding of 1 to 2% per year.2 Warfarin is also a burdensome long-term treatment, with many food and drug interactions . . .