Patients with migraine with aura (MWA) have a higher risk of stroke, according to a new review of the current research, which also suggests that a subset of auras may be induced by ischemia.
While migraines have not been shown to cause stroke, MWA is associated with multiple stroke risk factors, such as hypertension, hyperlipidemia, diabetes mellitus, cigarette smoking, atrial fibrillation, and patent foramen ovale. Women are 3 times as likely as men to have migraine, and high levels of estrogen increase the risk of migraine with aura (MWA), venous thromboembolism (VTE), and of stroke.
In women, MWA is also associated with biomarkers of endothelial activation, hormonal contraceptive use, pregnancy, and VTE. This suggests that a subset of auras may be secondary, that is, induced by ischemia related to microemboli or in situ thrombosis. Researchers at the Department of Neurology, University of Toledo College of Medicine and Life Sciences, reviewed the epidemiological evidence of the migraine-stroke relationship as well as the evidence for arterial, thrombophilic, and cardiac mechanisms to explain this connection. They also put forth the latest evidence for the diagnostic evaluation and treatment of MWA in the journal Headache.
MWA-associated ischemic stroke is more common in young (<45 years old) women with high frequency of migraine attacks, hormonal contraception use, and with pregnancy and preeclampsia. There is also increasing evidence that cardioembolism, often in conjunction with thrombophilia, plays a prominent role in MWA-associated cerebral infarction.
The common factors associated with MWA and with MWA-associated stroke suggest that patients with secondary, ischemia-induced aura may be at elevated risk of stroke. The researchers recommend a diagnostic evaluation of MWA that mirrors the evaluation of transient ischemic attack, given that prophylactic treatment targeting the ischemic origin of secondary aura may prevent migraine as well as stroke.