Related Experiment Videos
Antiplatelet therapy and risk of stroke
C H Hennekens1, M A Jonas, J E Buring
1Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
Insights
Aspirin therapy significantly lowers risks for vascular events like stroke and heart attack in patients with existing cardiovascular disease. Current data is inconclusive for primary stroke prevention, and risks of hemorrhagic stroke must be considered.
Area of Science:
- Cardiovascular Medicine
- Neurology
- Pharmacology
Background:
- Occlusive vascular disease poses significant health risks.
- Antiplatelet therapy, particularly aspirin, is a cornerstone in managing cardiovascular disease.
- Understanding aspirin's efficacy and risks is crucial for patient care.
Purpose of the Study:
- To evaluate the effectiveness of antiplatelet therapy, specifically aspirin, in reducing vascular events.
- To compare aspirin's efficacy against other antiplatelet agents and different dosage regimens.
- To assess aspirin's role in both secondary and primary prevention of stroke.
Main Methods:
- Systematic review and meta-analysis of 25 randomized controlled trials.
- Analysis of antiplatelet therapy in patients with prior cardiovascular disease.
- Examination of outcomes including nonfatal stroke, nonfatal myocardial infarction, and vascular deaths.
Main Results:
- Antiplatelet therapy reduced nonfatal stroke by 27% and nonfatal myocardial infarction by 32%.
- Aspirin was not found to be less effective than other agents; lower doses (300 mg) were as effective as higher doses.
- Early aspirin initiation during myocardial infarction significantly reduced stroke and vascular death.
Conclusions:
- Aspirin is effective in reducing vascular events in patients with established cardiovascular disease.
- Evidence for aspirin's primary stroke prevention benefit is inconclusive.
- The potential benefit of aspirin for ischemic stroke must be balanced against the increased risk of hemorrhagic stroke.
Abstract:
Antiplatelet therapy, especially with aspirin, reduces the risks of occlusive vascular disease, including ischemic stroke. In an overview of 25 trials of antiplatelet therapy in patients with prior cardiovascular disease, antiplatelet treatment reduced subsequent nonfatal stroke by 27% (P = 0.0001), nonfatal myocardial infarction by 32% (P = 0.0001), and all vascular deaths by 15% (P = 0.0003), with no evidence that other antiplatelet agents were more effective than aspirin, or that higher aspirin doses (900 to 1500 mg daily) were more effective than 300 mg, the lowest daily dose tested. If begun during the acute phase of myocardial infarction, aspirin reduces nonfatal stroke by 46% (P < 0.01) and vascular deaths by 23% (P < 0.00001) after 5 weeks. In primary prevention, currently available data are inconclusive regarding the effect of aspirin therapy on stroke. However, any potential benefit on ischemic stroke must be weighed against the possibility that aspirin could increase the risk of the less common, but clinically more severe, strokes of hemorrhagic etiology.