(HealthDay News) – Age is a significant factor in determining aspirin response in patients with stable coronary artery disease (CAD), according to a study published in the July 15 issue of The American Journal of Cardiology.
Mordehay Vaturi, MD, from Tel-Aviv University in Israel, and colleagues recruited 583 patients with stable CAD who had been treated with aspirin 75–325mg/day for at least one week. Patients were grouped by age: <75 years (438 patients) and patients aged ≥75 years (145). The VerifyNow Aspirin Test was used to determine response, and resistance was defined as ≥500 or 550 aspirin reaction units (ARU).
The researchers found that younger and older patients had similar baseline clinical profiles, including relative doses of aspirin therapy. In patients ≥75 years, the mean VerifyNow Aspirin Test score was significantly higher (450±54 vs. 434±53 ARU. Age remained a significant predictor of the VerifyNow score after adjusting for other variables. When the 500-ARU cut-off was used, aspirin resistance was higher in older patients (19 vs. 11%), but there was no difference when the 550-ARU cut-off was used (7 vs. 5%).
“In conclusion, aspirin response differs significantly by age in patients with stable CAD,” the authors write.