emerging medicine
By Katherine Osos
Drug Resistant
New research investigates the effectiveness of aspirin use in women with migraine.
FOR SEVERAL DECADES, older adults have been popping daily low-dose aspirin to ward off heart attack and stroke. Because migraineurs with aura are twice as likely to experience one of these vascular events, it’ s logical to assume aspirin should be one of their prevention staples. Recent research, however, may prove otherwise.
Although aspirin is the cornerstone of cost-effective treatment for reducing the risk of heart attack in men and stroke in women, the vascular benefits of aspirin for people with migraine are unknown. In a study being conducted at Swedish Medical Center and The University of Washington in Seattle, researchers funded by the National Headache Foundation are investigating the effectiveness of aspirin on platelet function in women with migraine.
“ Our short-term objective with this study is to determine the prevalence of aspirin resistance in women with migraine,” says Jill Jesurum, PhD, principal investigator of the study.“ Our long-term objective is to contribute to the development of guidelines for heart attack and stroke prevention in migraine. There are currently no published guidelines on this.”
Because the U. S. Preventive Services Task Force recommends against the use of aspirin for the primary prevention of stroke in women less than age 55, specialized guidelines are necessary for migraineurs.“ Even cardiovascular specialists do not see the need of aspirin for prevention in women under 55,” says Cindy Fuller, PhD, the study’ s director.“ But most migraineurs are premenopausal, so how do you reduce the risk in this group?”
Aspirin is often used to stop blood platelets from forming clots, which can cause heart attack or stroke. Aspirin resistance means the drug isn’ t able to adequately inhibit platelet function and prevent the formation of clots, increasing a person’ s chance of a cardiovascular event.
Jesurum and her team are curious whether migraineurs are even more susceptible to aspirin resistance due to platelet irregularities associated with migraine and frequent use of nonsteroidal antiinflammatory drugs, which interfere with aspirin’ s effect. Although the mechanism is not understood, aspirin therapy for cardiovascular disease is four times more likely to be ineffective in women. Because the majority of migraineurs are women, it stands to reason that there may be a high incidence of aspirin resistance in the migraine population.
According to Jesurum, most medical providers do not test for aspirin resistance before prescribing the drug. They simply assume it is working as intended.
Jesurum says she is particularly concerned about the subsets of migraineurs who may have even higher risks for heart attack or stroke, such as those who experience migraine with aura and use tobacco or oral contraceptives, and those who have a patent foramen ovale, an incomplete closure of the upper heart chambers.
The team’ s preliminary research, the Response to Aspirin in Migraine Study( RAM), evaluated 50 episodic migraineurs who took 325 mg of aspirin for 14 to 21 consecutive days and found that 8 % of them had aspirin resistance. This is significantly higher than published reports that fewer than 1 % of nonmigraineurs and 3.2 % of people with cardiovascular disease have aspirin resistance to 325 mg. All of the migraineurs who were found to have aspirin resis-
16 HEAD WISE | Volume 1, Issue 1 • 2011