For whom is daily aspirin (acetylsalicylic acid) recommended?

Daily Aspirin Recommendations

Daily aspirin (75-100 mg) is strongly recommended for secondary prevention in patients with established cardiovascular disease, including those with previous myocardial infarction, stroke, transient ischemic attack, or other atherosclerotic cardiovascular disease, but is generally not recommended for primary prevention except in specific high-risk populations. 1, 2

Secondary Prevention Indications

• Aspirin 75-100 mg daily is recommended for all patients with previous myocardial infarction or revascularization 1
• Aspirin is recommended for patients with previous stroke or transient ischemic attack 1, 2
• Aspirin provides benefit in patients with stable or unstable angina, peripheral arterial disease, and those who undergo coronary artery bypass grafting or angioplasty 2, 3
• For patients with documented aspirin allergy, clopidogrel 75 mg daily is recommended as an alternative 1, 2
• Dual antiplatelet therapy (aspirin plus P2Y12 inhibitor) is recommended for at least 1 year following acute coronary syndrome 1, 2

Primary Prevention Indications

• Aspirin is not routinely recommended for primary prevention in most individuals due to bleeding risks that may offset cardiovascular benefits 1
• Aspirin may be considered in adults with diabetes who have a 10-year cardiovascular risk >10% and are not at increased bleeding risk 1
• For diabetes patients, aspirin may be considered in men >50 years and women >60 years with at least one additional major cardiovascular risk factor (smoking, hypertension, dyslipidemia, albuminuria, or family history of premature cardiovascular disease) 1
• Aspirin should not be recommended for primary prevention in adults with diabetes who are at low risk (men <50 years and women <60 years with no additional risk factors) 1
• Aspirin is contraindicated in patients <21 years due to risk of Reye syndrome 1

Dosing Considerations

• For long-term prevention, daily doses of 75-100 mg are recommended 1, 2
• In acute settings (myocardial infarction, stroke), a loading dose of 160-325 mg is recommended, followed by daily maintenance doses of 75-100 mg 1, 4
• Lower doses (75-100 mg) are preferred over higher doses to minimize bleeding risk while maintaining efficacy 2, 5

Risk-Benefit Assessment

• The main adverse effect of aspirin is increased gastrointestinal bleeding risk (approximately 2-4 per 1,000 middle-aged persons and 4-12 per 1,000 older persons given aspirin for 5 years) 1, 2
• Risk factors for increased bleeding include age >70 years, uncontrolled hypertension, concomitant use of NSAIDs or anticoagulants, and history of gastrointestinal bleeding 1, 2
• For adults with cardiovascular risk >1% per year, the number of cardiovascular events prevented will be approximately equal to or greater than the number of bleeding events induced 1, 2
• In secondary prevention, the benefits of aspirin substantially outweigh the bleeding risks 1, 6

Special Considerations

• Proton pump inhibitors may be used to decrease the risk of recurrent aspirin-related gastrointestinal bleeding, but routine use for primary prevention of bleeding is not clearly cost-effective 1
• Aspirin resistance may occur in some patients, particularly those with diabetes, but evidence is insufficient to recommend higher doses empirically 1, 5
• Aspirin should be used as an adjunct to, not a replacement for, management of other cardiovascular risk factors 3, 6