HealthDay News — Patients who are resistant to aspirin may be at risk for larger, more severe strokes, research being presented at the annual meeting of the American Academy of Neurology, to be held from April 18 to 25 in Washington, D.C, suggests.

“The concept of ‘resistance’ to aspirin has been controversial, and the testing of resistance varies across the different studies,” noted the Mi Sun Oh, MD, of the department of neurology at the Hallym University College of Medicine in Seoul, South Korea, and colleagues in a press release from the American Academy of Neurology (AAN).

To investigate the efficacy of aspirin in patients at risk for stroke, the investigators followed 310 patients who had an ischemic stroke and been taking aspirin for at least seven days before the first stroke symptoms.

Of the patients, 27.7% (n=86) were resistant to aspirin. The median stroke severity score was four, with scores ranging from three to 11, in the aspirin-resistant group. For patients who responded to aspirin, the average stroke severity score was three, with scores ranging from one to six.

“Eventually we may be able to identify people who are likely to be resistant to aspirin and give them higher doses or different drugs to prevent blood clots,” said Oh.

“However, we need better ways to identify people with aspirin resistance before any changes can be made. For now, people who are taking low-dose aspirin to prevent blood clotting and stroke should continue to do so.”