Understanding Risk Factors Involved in Developing a Second Blood Clot.
The purpose of this study is to develop a way to predict which patients diagnosed with idiopathic blood clots can safely stop warfarin therapy after six months. We will use patient characteristics, blood test results and imaging test results to identify those patients who have the lowest risk of developing a new blood clot after warfarin is stopped.
Deep Vein Thrombosis
|Study Design:||Time Perspective: Prospective|
|Official Title:||REcurrent VEnous Thromboembolism Risk Stratification Evaluation A Study to Develop a Clinical Prediction Rule to Predict Low Recurrence Risk in Patients With Idiopathic Venous Thromboembolism.|
|Study Start Date:||October 2002|
|Estimated Study Completion Date:||September 2015|
The risk of recurrent VTE in patients with idiopathic VTE subsequent to three to six months of oral anticoagulant therapy remains high (5-27% per year). The risk of recurrent VTE, however, is not likely high enough to justify indefinite anticoagulation in all patients with a first idiopathic VTE due to the rate of major bleeding with oral anticoagulants (2-6% per year), the inconvenience and cost of oral anticoagulant therapy, monitoring of oral anticoagulant therapy (e.g. prescription costs, time off work to go for lab tests, parking etc) and the lifestyle limitations of oral anticoagulant therapy (avoidance of certain physical activities, dietary restrictions, avoidance of pregnancy). Further, as some have argued, perhaps all that anticoagulant therapy achieves is to delay recurrent VTE and, as a recent editorial suggested, a tailored approached is required to determine sub-groups who require lifelong anticoagulation. A means to stratify patients with idiopathic VTE to identify a group at low risk of recurrent VTE who could safely discontinue oral anticoagulants subsequent to six months of therapy would be a significant advance in the care of these patients.
|Canada, Nova Scotia|
|QE II Health Sciences Centre|
|Halifax, Nova Scotia, Canada, B3H 2Y9|
|London Health Sciences Centre|
|London, Ontario, Canada, N6A 4G5|
|The Ottawa Hospital|
|Ottawa, Ontario, Canada, K1Y 4E9|
|Montreal Jewish General Hospital|
|Montreal, Quebec, Canada, H3T 1E2|
|Hopital du Sacre Coeur|
|Montreal, Quebec, Canada, H4J 1C5|
|Montreal General Hospital|
|Montreal, Quebec, Canada, H3G 1A4|
|CHU de le Cavale Blanche|
|Principal Investigator:||Marc Rodger, MD MSc||OHRI|