Aspirin for Preventing the Recurrence of Venous Thromboembolism

About 20% of patients with venous thrombosis or embolism but no defined risk factors have a recurrence within the first 2 years after stopping anticoagulation therapy. These authors report that 100 mg of aspirin a day nearly halved the risk of recurrence, with no increase in bleeding. The risk of recurrence of venous thromboembolism persists for many years after anticoagulant treatment is withdrawn. 1 , 2 This risk is particularly high among patients with unprovoked venous thromboembolism, 2 about 20% of whom have a recurrence within 2 years after treatment with vitamin K antagonists has been discontinued. 3 – 6 Extending treatment with these agents reduces the risk of recurrence but is associated with an increased risk of bleeding, as well as the inconvenience and expense of laboratory monitoring and dose adjustments. 7 The role of aspirin in the primary prevention of venous thromboembolism has been evaluated in various clinical settings. 8 – 11 In . . .