The researchers determined whether aspirin is associated with a mortality benefit in stable patients with known or suspected coronary disease. They also identified patient characteristics that predict the maximum absolute mortality benefit from aspirin.
The results of the study were published in this week's Journal of the American Medical Association.
A total of 6174 consecutive adult patients were enrolled in the prospective, non-randomized, cohort study, which was conducted between 1990 and 1998.
All individuals were undergoing stress echocardiography for evaluation of known or suspected coronary disease. Some 2310 (37%) subjects were taking aspirin.
Patients with significant valvular disease or documented contraindication to aspirin use, including peptic ulcer disease, renal insufficiency, and use of nonsteroidal anti-inflammatory drugs, were excluded.
During a median of 3.1 years of follow-up, 276 patients (4.5%) died.
| Greatest aspirin benefits in:|
- Known coronary artery disease
- Those with impaired exercise capacity
|Journal of the American Medical Association|
In a simple univariable analysis, there was found to be no association between aspirin use and mortality (4.5% vs 4.5%).
However, the researchers then adjusted for age, sex, standard cardiovascular risk factors, use of other medications, coronary disease history, ejection fraction, exercise capacity, heart rate recovery, and echocardiographic ischemia. They then found that aspirin use was associated with reduced mortality (hazard ratio [HR], 0.67).
In further analysis using matching by propensity score, 1351 patients who were taking aspirin were at lower risk for death than 1351 patients not using aspirin (4% vs 8%, respectively; HR, 0.53).
After adjusting for the propensity for using aspirin, as well as other possible confounders and interactions, aspirin use remained associated with a lower risk for death (adjusted HR, 0.56).
The investigators found that the patient characteristics associated with the most aspirin-related reductions in mortality were older age, known coronary artery disease, and impaired exercise capacity.
Dr Patricia A. Gum, of the Department of Cardiology, Cleveland Clinic Foundation, concluded on behalf of her colleagues, "Aspirin use among patients undergoing stress echocardiography was independently associated with reduced long-term all-cause mortality. This was particularly so among older patients, those with known coronary artery disease, and those with impaired exercise capacity."