Premium
Comparison of 1 month with 3 months of anticoagulation for a first episode of venous thromboembolism associated with a transient risk factor
Author(s) -
Kearon C.,
Ginsberg J. S.,
Anderson D. R.,
Kovacs M. J.,
Wells P.,
Julian J. A.,
Mackin B.,
Demers C.,
Douketis J.,
Turpie A. G.,
Van Nguyen P.,
Green D.,
Kassis J.,
Kahn S. R.,
Solymoss S.,
Desjardins L.,
Geerts W.,
Johnston M.,
Weitz J. I.,
Hirsh J.,
Gent M.
Publication year - 2004
Publication title -
journal of thrombosis and haemostasis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.947
H-Index - 178
eISSN - 1538-7836
pISSN - 1538-7933
DOI - 10.1046/j.1538-7836.2004.00698.x
Subject(s) - medicine , warfarin , discontinuation , risk factor , venous thromboembolism , placebo , anticoagulant , surgery , confidence interval , incidence (geometry) , absolute risk reduction , anesthesia , thrombosis , atrial fibrillation , physics , alternative medicine , pathology , optics
Summary. Background : The risk of recurrence is lower after treatment of an episode of venous thromboembolism associated with a transient risk factor, such as recent surgery, than after an episode associated with a permanent, or no, risk factor. Retrospective analyses suggest that 1 month of anticoagulation is adequate for patients whose venous thromboembolic event was provoked by a transient risk factor. Methods : In this double‐blind study, patients who had completed 1 month of anticoagulant therapy for a first episode of venous thromboembolism provoked by a transient risk factor were randomly assigned to continue warfarin or to placebo for an additional 2 months. Our goal was to determine if the duration of treatment could be reduced without increasing the rate of recurrent venous thromboembolism during 11 months of follow‐up. Results : Of 84 patients assigned to placebo, five (6.0%) had recurrent venous thromboembolism, compared with three of 81 (3.7%) assigned to warfarin, resulting in an absolute risk difference of 2.3%[95% confidence interval (CI) − 5.2, 10.0]. The incidence of recurrent venous thromboembolism after discontinuation of warfarin was 6.8% per patient‐year in those who received warfarin for 1 month and 3.2% per patient‐year in those who received warfarin for 3 months (rate difference of 3.6% per patient‐year; 95% CI − 3.8, 11.0). There were no major bleeds in either group. Conclusion : Duration of anticoagulant therapy for venous thromboembolism provoked by a transient risk factor should not be reduced from 3 months to 1 month as this is likely to increase recurrent venous thromboembolism without achieving a clinically important decrease in bleeding.