D-dimer to Select Patients With First Unprovoked Venous Thromboembolism Who Can Have Anticoagulants Stopped at 3 Months

Study Overview
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Brief Summary
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The purpose of this study is to determine if the risk of recurrent venous thromboembolism (VTE) after stopping therapy is low and acceptable in patients with a first unprovoked proximal deep vein thrombosis (DVT) or pulmonary embolism (PE) who have completed 3 months of therapy and who have a negative D-dimer test on therapy and 1 month after stopping therapy.

Official Title
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A Cohort Study to Test That There is a Low Risk of Recurrent VTE in Patients With a First Episode of Unprovoked VTE Who Stop Anticoagulant Therapy After 3 Months of Treatment in Response to Negative D-dimer Testing

Conditions
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Deep Vein Thrombosis, Pulmonary Embolism

Intervention / Treatment
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* Other: Discontinue anticoagulant therapy (Negative d-dimer)
* Other: Continue on anticoagulant therapy (positive d-dimer)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Be >= 18 years of age Have had ONE episode of unprovoked proximal DVT and/or PE Have completed 3 uninterrupted months of warfarin therapy (target INR of 2.0-3.0) Exclusion Criteria: Another indication for long-term anticoagulation (e.g., atrial fibrillation) A high risk of bleeding as evidenced by any of the following: Age greater than 75 years Previous episode of major bleeding where the cause was not effectively treated Known chronic thrombocytopenia with a platelet count of less than 120,000 x 10^9 /L Known chronic renal impairment with a creatinine of more than 150 mumols /litre (1.7 mg/dl) Known chronic liver disease with a total bilirubin of more than 25 mumols /litre (1.5 mg/dl) Active peptic ulcer disease Poor compliance with, or control of, anticoagulant therapy during initial treatment Requires dual antiplatelet therapy (e.g. aspirin and clopidogrel) A vena caval filter Has had D-dimer testing performed within 2 months of potential enrollment other than for evaluation of suspected recurrent VTE that was not confirmed Has a life expectancy less than 5 years Is unable to attend follow-up visits because of geographic inaccessibility Is participating in a competing clinical investigation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: No Anticoagulant Therapy<br>No Anticoagulant Therapy | Other: Discontinue anticoagulant therapy (Negative d-dimer)<br>* Patients with negative d-dimer discontinue long-term anticoagulant therapy.<br>|
| Other: Anticoagulant Therapy<br>Continue on anticoagulant therapy | Other: Continue on anticoagulant therapy (positive d-dimer)<br>* Patients with positive d-dimer continue or re-start on anticoagulant therapy<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Suspected Recurrent DVT |  | up to 7 years | 
| Suspected (recurrent) pulmonary embolism |  | up to 7 years | 
| Bleeding |  | up to 7 years | 
| Death |  | up to 7 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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unprovoked deep vein thrombosis, unprovoked pulmonary embolism, anticoagulant therapy