Bleeding Risks With Aspirin Use for Primary Prevention in Adults: A Systematic Review for the U.S. Preventive Services Task Force
Related Experiment Video
Updated: Mar 22, 2026
Interventional Diagnostic Procedure: A Practical Guide for the Assessment of Coronary Vascular Function
Published on: March 15, 2022
Insights
Regular aspirin use for cardiovascular disease primary prevention significantly increases major gastrointestinal bleeding risk by 58% and hemorrhagic stroke risk by 27%. Individual patient assessment is crucial due to variable bleeding risks.
Area of Science:
- Cardiovascular Disease Prevention
- Gastrointestinal Bleeding
- Hemorrhagic Stroke Risk
Background:
- Balancing aspirin's risks and benefits is critical for primary prevention strategies.
- Assessing the safety of aspirin in cardiovascular disease (CVD) primary prevention is essential.
Purpose of the Study:
- To evaluate the risk of serious bleeding associated with regular aspirin use in primary prevention of cardiovascular disease.
- To quantify the increased risk of major gastrointestinal bleeding and hemorrhagic stroke.
Main Methods:
- Systematic review and meta-analysis of randomized controlled trials, cohort studies, and meta-analyses.
- Data sources included PubMed, MEDLINE, and Cochrane Central Register of Controlled Trials up to January 2015.
- Study quality was assessed, and data were extracted and verified by multiple investigators.
Main Results:
- Very-low-dose aspirin (≤100 mg) increased major gastrointestinal bleeding risk by 58% (OR, 1.58) and hemorrhagic stroke risk by 27% (OR, 1.27).
- Estimated excess major bleeding events were 1.39 per 1000 person-years for GI bleeding and 0.32 for hemorrhagic stroke.
- Bleeding risks may be higher in older individuals, men, and those with CVD risk factors.
Conclusions:
- The study had limited power to detect effects on hemorrhagic stroke.
- Harms beyond serious bleeding were not examined in this analysis.
- Individualized assessment of aspirin's bleeding risks and benefits is necessary for safe primary prevention.
Background:
The balance between potential aspirin-related risks and benefits is critical in primary prevention.
Purpose:
To evaluate the risk for serious bleeding with regular aspirin use in cardiovascular disease (CVD) primary prevention.
Data Sources:
PubMed, MEDLINE, Cochrane Central Register of Controlled Trials (2010 through 6 January 2015), and relevant references from other reviews.
Study Selection:
Randomized, controlled trials; cohort studies; and meta-analyses comparing aspirin with placebo or no treatment to prevent CVD or cancer in adults.
Data Extraction:
One investigator abstracted data, another checked for accuracy, and 2 assessed study quality.
Data Synthesis:
In CVD primary prevention studies, very-low-dose aspirin use (≤100 mg daily or every other day) increased major gastrointestinal (GI) bleeding risk by 58% (odds ratio [OR], 1.58 [95% CI, 1.29 to 1.95]) and hemorrhagic stroke risk by 27% (OR, 1.27 [CI, 0.96 to 1.68]). Projected excess bleeding events with aspirin depend on baseline assumptions. Estimated excess major bleeding events were 1.39 (CI, 0.70 to 2.28) for GI bleeding and 0.32 (CI, -0.05 to 0.82) for hemorrhagic stroke per 1000 person-years of aspirin exposure using baseline bleeding rates from a community-based observational sample. Such events could be greater among older persons, men, and those with CVD risk factors that also increase bleeding risk.
Limitations:
Power to detect effects on hemorrhagic stroke was limited. Harms other than serious bleeding were not examined.
Conclusion:
Consideration of the safety of primary prevention with aspirin requires an individualized assessment of aspirin's effects on bleeding risks and expected benefits because absolute bleeding risk may vary considerably by patient.
Primary Funding Source:
Agency for Healthcare Research and Quality.
Related Concept Videos
01:20Antiplatelet Drugs: Prostaglandin Synthesis, P2Y12 and Glycoprotein IIb/IIIa Inhibitors
Prostaglandin synthesis inhibitors, exemplified by the widely known aspirin, wield their power by irreversibly acetylating...
01:29Venous Thrombosis III: Interprofessional Care
01:30Venous Thrombosis IV: Nursing Management
01:24Disorders of Hemostasis
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
01:30Anticoagulant Drugs: Low-Molecular-Weight Heparins
01:18Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants
Warfarin, a prominent vitamin K antagonist family member, exerts its effect by inhibiting the enzyme VKORC1 (vitamin K epoxide reductase complex 1). By hindering this enzyme, warfarin...