Purpose: To review the effectiveness of medical treatments for stroke prevention in patients at elevated risk for stroke.
Data Sources: English-language articles published after 1977 and indexed in MEDLINE under the following Medical Subject Heading terms: anticoagulants, aspirin, dipyridamole, ticlopidine, or sulfinpyrazone, combined with cerebrovascular disorders.
Study Selection: Randomized controlled trials of anticoagulant or platelet antiaggregant treatment reporting subsequent stroke and myocardial infarction, death, or complications in persons with asymptomatic carotid stenosis or bruit, transient ischemic attack (TIA), previous stroke, nonvalvular atrial fibrillation, or other vascular diseases.
Data Extraction: Of 900 articles identified, 33 were selected by two independent reviewers and abstracted for outcome events and person-years of follow-up.
Results: In patients with nonvalvular atrial fibrillation, warfarin is highly effective in reducing stroke and death but may result in more complications. Aspirin appears to be less effective and less risky than anticoagulation. In patients with TIA or minor stroke, both aspirin and ticlopidine reduce the risk for stroke. In patients who have had myocardial infarction, warfarin is effective but had high complication rates in the reviewed studies. Aspirin slightly reduces the risk for stroke.
Conclusions: Warfarin is strongly recommended for persons with nonvalvular atrial fibrillation who are older than 60 years or who have additional risk factors for stroke. Aspirin is recommended for persons at elevated risk for bleeding while receiving anticoagulants. For persons with TIA or minor stroke, aspirin should be used first. Patients who do not respond to or tolerate aspirin or who have had a major stroke are reasonable candidates for ticlopidine. For patients who have had myocardial infarction, aspirin is recommended for the prevention of secondary myocardial infarction but not of stroke.