Long-term risk of venous thrombosis after stopping anticoagulants for a first unprovoked event: A multi-national cohort. Issue 143 (July 2016)

• Record Type: Journal Article
• Authors: Rodger, Marc A.; Scarvelis, Dimitri; Kahn, Susan R.; Wells, Philip S.; Anderson, David A.; Chagnon, Isabelle; Le Gal, Grégoire; Gandara, Esteban; Solymoss, Susan; Sabri, Elham; Kovacs, Judy; Kovacs, Michael J.
• Is Part Of: Thrombosis research. Issue 143(2016)
• Page Start: 152
• Page End: 158
• Publication Date: 2016-07
• Subjects: Venous thrombosis -- anticoagulants -- therapy -- prognosis -- risk factors; Thrombosis -- Periodicals; 616.135
• DOI: 10.1016/j.thromres.2016.03.028
• Languages: English
• ISSNs: 0049-3848

Abstract

Abstract: Background: Choosing short-term (3-6 months) or indefinite anticoagulation after a first unprovoked venous thromboembolic event (VTE) is a common and difficult clinical decision. The long-term absolute risk of recurrent VTE after a first unprovoked VTE, in all patients and sub-groups, is not well established, hindering decision making. Methods: We conducted a multi-center multi-national prospective cohort study in first unprovoked VTE patients to establish the long-term risk of recurrent VTE after short-term anticoagulation in first unprovoked VTE patients (and sub-groups).We followed patients for symptomatic suspected VTE off of OAT. Suspected recurrent VTE was investigated with reference to baseline imaging and then independently and blindly adjudicated. Findings: We recruited 663 participants between October, 2001 and March 2006 with the last follow-up in April 2014. During a mean 5.0 years of follow-up, 165/663 suspected VTE (in 408 patients) were adjudicated as recurrent VTE resulting in an annualized risk of recurrent VTE of 5.0% (95% CI: 4.2-5.8%) with a cumulative risk of 29.6% at 8 years. Men had a 7.6% (95% CI: 6.3-9.2%) annual risk of recurrent VTE. High risk women (2 or more HERDOO2 points; see text) had an annual risk of recurrent VTE of 5.9% (95% CI: 4.2-8.1%). Low risk women (1 or 0 HERDOO2 points) had 1.1% (95% CI: 0.6-2.0%) annual risk of recurrent VTE with a cumulative risk of 8.7% at 8 years. Interpretation: Men and high risk women with unprovoked VTE should be considered for long-term anticoagulant therapy given a high risk of recurrent VTE after long-term follow-up. Women with a low HERDOO2 score may be able to safely discontinue anticoagulants. Funding: This study was funded by the Canadian Institutes of Health Research (Grant # MOP 64319) and Heart and Stroke Foundation of Ontario (Grant # NA 6771). Registered atwww.clinicaltrials.gov identifier: NCT00261014 Highlights: The long-term risk of recurrent VTE in unprovoked venous thrombosis patients is poorly studied. We showed in a multi-national prospective cohort study with long-term follow-up that the risk of recurrent VTE is high but not high enough to clearly guide anticoagulant decision making. Men and women with a HERDOO2 score > 1 are at high risk of recurrent venous thrombosis over long-term follow-up The "Men continue and HERDOO2" rule must be prospectively validated before being used clinically