"This is the first controlled retrospective study to investigate the potential risk of suffering ischemic stroke shortly after discontinuing aspirin," said Patrik Michel, M.D., co-author of the study and director of the acute stroke unit at Lausanne University Hospital in Lausanne, Switzerland.
The results confirm and extend previous observations in stroke survivors who stopped taking aspirin.
Aspirin is the most often prescribed medication to prevent a recurrent stroke or heart attack, Michel said. This study reinforces the importance of compliance with aspirin therapy in patients with symptomatic atherosclerosis, including previous stroke. Patients and physicians should be aware of a possible increased risk of stroke when aspirin is stopped.
Researchers selected 309 patients who had a stroke or transient ischemic attack (TIA) and were on long-term aspirin therapy for secondary prevention of heart attack and stroke. They matched these patients with 309 control patients who had a stroke or TIA more than six months before and were also taking long-term aspirin therapy.
The average age of the entire study population was 71 years, and 62 percent were men. In each group about 69 percent had hypertension, 20 percent had diabetes, and 14 percent were smokers. In the study group, 52 percent had dyslipidemia compared to 58 percent in the control group (not statistically significant). In the study group, 36 percent had coronary heart disease compared to 18 percent in the control group (a statistically significant difference). Also, a similar number of patients in both groups were taking either a 100 mg or 300 mg dosage of aspirin.