May 06, 2016
Annals of Internal Medicine
TAKE-HOME MESSAGE
- The authors of this systematic review evaluated the risk of severe bleeding associated with the use of aspirin for the primary prevention of cardiovascular disease (CVD). The use of low-dose aspirin was associated with a 58% increased risk of major gastrointestinal bleeding and a 27% increased risk of hemorrhagic stroke. The risk of bleeding events could be significantly higher in older patients, male patients, and patients with increased bleeding risk due to CVD risk factors.
- Patients require an individualized risk assessment to evaluate the potential risks and benefits of aspirin use before initiating primary preventive therapy.
Abstract
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.