Predicting Bleeding Risk on Anticoagulant Therapy for Venous Thromboembolism

Venous Thromboembolism Clinical Trial

Official title:

Development and Validation of Clinical Prediction Rules for Bleeding for Patients on Anticoagulant Therapy for Venous Thromboembolism

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00788736
• Other study ID #: OHREB 2008270-01H
• Secondary ID: MOP130388
• Status: Completed
• Phase: N/A
• First received: November 10, 2008
• Last updated: October 25, 2016
• Start date: September 2008
• Est. completion date: October 2016

Study information

• Verified date: October 2016
• Source: Ottawa Hospital Research Institute
• Contact: n/a
• Is FDA regulated: No
• Health authority: Canada: Ethics Review Committee
• Study type: Observational

Clinical Trial Summary

The main objective of the study is to develop or validate a clinical prediction rule for major bleeding in patients on oral anticoagulant therapy who have been safely anticoagulated without bleeding or venous thromboembolism (VTE) recurrence for at least 3 months since diagnosis and are being considered for long-term oral anticoagulant therapy.

Description:

Oral anticoagulant therapy for patients who are at risk of developing blood clotting problems is used by between 400,000-600,000 Canadians annually. The use of this drug represents the most common cause of patient adverse medical outcomes due to medical errors. Furthermore, many patients have adverse outcomes using these drugs because physicians are not able to predict which patients are likely to have bleeding outcomes. Much effort has gone into developing ways to predict which patients are at risk of clotting but almost no work has gone into ways of predicting which patients would be at high risk of bleeding. This information is required to balance off the risk-benefits and to enable physicians and patients to understand the risks and benefits of taking these medications. Our study will develop a tool that can be used to predict bleeding risk in patients taking oral anticoagulant therapy. It will enable more informed decision making by both physicians and patients and will result in better control of the use of these drugs. In addition, patients who are at risk for being difficult to accurately dose on oral anticoagulants will be identified through our study.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 2537
• Est. completion date: October 2016
• Est. primary completion date: September 2016
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• >=18 years old

• provoked or unprovoked venous thromboembolism

• objectively confirmed venous thromboembolism

• treated with an oral anticoagulant(vitamin K antagonist or new oral anticoagulant) for at least 3 months with plans to continue long-term

• if taking a vitamin K antagonist; INR target is between 2.0-3.0

• if taking a vitamin K antagonist; must have taken it for the last 3 consecutive weeks (minimum)

Exclusion Criteria:

• major bleeding while taking oral anticoagulants

• active bleeding at study enrollment

• active cancer - current or at the time of VTE diagnosis

• unable to provide written informed consent

• refusal to provide written informed consent

Study Design

Observational Model: Cohort, Time Perspective: Prospective

Related Conditions & MeSH terms

• Hemorrhage
• Thromboembolism
• Venous Thromboembolism

Locations

Country	Name	City	State
Canada	Queen Elizabeth II Health Sciences Centre	Halifax	Nova Scotia
Canada	Hamilton General Hospital	Hamilton	Ontario
Canada	Hamilton Health Sciences	Hamilton	Ontario
Canada	London Health Sciences Centre	London	Ontario
Canada	Hopital du Sacre Coeur de Montreal	Montreal	Quebec
Canada	Montreal General Hospital	Montreal	Quebec
Canada	Sir Mortimer B Davis Jewish General Hospital	Montreal	Quebec
Canada	St. Mary's Hospital Centre	Montreal	Quebec
Canada	Ottawa Hospital Research Institute	Ottawa	Ontario
United Kingdom	Oxford Haemophilia and Thrombosis Centre, Churchill Hospital	Oxford
United States	Lahey Clinic	Burlington	Massachusetts
United States	Henry Ford Health System	Detroit	Michigan

Sponsors (3)

Lead Sponsor	Collaborator
Ottawa Hospital Research Institute	Canadian Institutes of Health Research (CIHR), Heart and Stroke Foundation of Ontario

Countries where clinical trial is conducted

United States,  Canada,  United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Major bleeding (International Society on Thrombosis and Haemostasis(ISTH) criteria)		ongoing for 3-7 years with follow-up phone calls at 6-month intervals	Yes
Secondary	Clinically relevant non-major bleeding (International Society on Thrombosis and Haemostasis(ISTH) criteria)		ongoing for 3-7 years with follow-up phone calls at 6-month intervals	Yes
Secondary	recurrent venous thromboembolism		ongoing for 3-7 years with follow-up phone calls at 6-month intervals	Yes
Secondary	death (all causes)		ongoing for 3-7 years with follow-up phone calls at 6-month intervals	Yes