PFA-100-measured aspirin resistance linked to CV events

(HealthDay)—Aspirin resistance, measured using the Platelet Function Analyzer (PFA)-100 system, is associated with cardiovascular events in aspirin-treated patients, according to a study published online Oct. 21 in the Journal of Clinical Pharmacy and Therapeutics.

H.Y. Chen, M.D., from Taipei City Hospital in Taiwan, and P. Chou, Ph.D., from the Yang-Ming University School of Medicine in Taiwan, assessed aspirin resistance in 465 aspirin-treated patients from the outpatient department. Patients were followed for five years for hospitalization for any acute cardiovascular event.

The researchers found that 20 percent of the patients had aspirin resistance. There was a strong correlation for prior hospitalization history of cardiovascular events with aspirin resistance (P = 0.001). Cardiovascular events had developed in 11 patients with aspirin resistance (eight stroke and three myocardial infarction) and in nine patients without aspirin resistance (four stroke and five myocardial infarction) at the five-year follow-up (12.1 versus 2.4 percent; P < 0.001). A strong correlation was seen between aspirin resistance and cardiovascular events at the five-year follow-up in multivariate analysis (adjusted odds ratio, 4.28; 95 percent confidence interval, 1.64 to 11.2; P = 0.03).

"We posit that measuring aspirin resistance by PFA-100 may play a role in clinical cardiovascular prevention," the authors write.