Warfarin Versus Aspirin Recurrent Stroke Study

Sponsor

Columbia University (Other)

Overall Status

Completed

CT.gov ID

NCT00027066

Collaborator

National Institute of Neurological Disorders and Stroke (NINDS) (NIH)

2,206

Enrollment

Location

Arms

101

Duration (Months)

21.8

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The goal of this study is to compare aspirin to warfarin for the prevention of recurrent stroke.

Condition or Disease	Intervention/Treatment	Phase
Stroke	Drug: Active Aspirin Drug: Active Warfarin Drug: Aspirin placebo Drug: Warfarin placebo	Phase 3

Detailed Description

This study compared aspirin to warfarin to determine optimal therapy for the prevention of recurrent stroke. Both drugs slow clotting of the blood. Blood clots are involved in the final stages of the most common type of stroke due to blockage of the vessels that supply oxygen-rich blood to the brain. Aspirin affects the blood platelets, while warfarin inhibits circulating clotting proteins in the blood. Numerous previous studies have proven that use of aspirin reduces recurrent stroke by about 25 percent. Part of the controversy about aspirin versus warfarin for stroke prevention has been the thinking among clinicians that warfarin may be a better blood thinner than aspirin to prevent almost all forms of stroke, but that it has greater side effects, increased risk of hemorrhage, and higher costs due to the need for blood tests to monitor the treatment effect for patients.

To make the aspirin and warfarin arms of the study as unbiased as possible, the investigators matched both groups of patients for primary stroke severity, age, gender, education, and race/ethnicity. The two groups were also matched for stroke risk factors, including hypertension, diabetes, cardiac disease, smoking, alcohol consumption, and physical activity. The investigators used an aspirin dose of 325 mg/day and a warfarin dose specifically tailored to each individual patient.

This study found that aspirin works as well as warfarin in helping to prevent recurrent strokes in most patients.

Study Design

Study Type:

Interventional

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

Double (Participant, Investigator)

Primary Purpose:

Prevention

Official Title:

A Comparison of Warfarin and Aspirin for the Prevention of Recurrent Ischemic Stroke

Study Start Date :

Jun 1, 1993

Actual Primary Completion Date :

Jun 1, 2000

Actual Study Completion Date :

Nov 1, 2001

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: Active Warfarin and Aspirin Placebo One 2 mg scored tablet daily of Warfarin and one 325 mg tablet daily of aspirin placebo.	Drug: Active Warfarin 2mg scored tablet daily Drug: Aspirin placebo 325mg aspirin placebo pill
Active Comparator: Active Aspirin and Warfarin Placebo One 325 mg tablet daily of aspirin and one 2 mg scored tablet daily of Warfarin placebo.	Drug: Active Aspirin 325mg tablet daily Drug: Warfarin placebo 2mg scored placebo tablet

Arm

Intervention/Treatment

Active Comparator: Active Warfarin and Aspirin Placebo

One 2 mg scored tablet daily of Warfarin and one 325 mg tablet daily of aspirin placebo.

Drug: Active Warfarin

2mg scored tablet daily

Drug: Aspirin placebo

325mg aspirin placebo pill

Active Comparator: Active Aspirin and Warfarin Placebo

One 325 mg tablet daily of aspirin and one 2 mg scored tablet daily of Warfarin placebo.

Drug: Active Aspirin

325mg tablet daily

Drug: Warfarin placebo

2mg scored placebo tablet

Outcome Measures

Primary Outcome Measures

Eligibility Criteria

Criteria

Ages Eligible for Study:

30 Years to 85 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion:

Acceptable candidates for warfarin therapy
Had an ischemic stroke within the previous 30 days
Had scores of 3 or more on the Glasgow Outcome Scale

Exclusion:

Base-line INR above the normal range (more than 1.4)
History of stroke due to a procedure or that was attributed to high-grade carotid stenosis for which surgery was planned
History of stroke associated with an inferred cardioembolic source