A systematic and meta-analysis published in the British Medical Journal finds that migraine with aura is associated with a twofold increased risk of stroke. Migraine with aura involves pain preceded or accompanied by temporary visual or sensory disturbances.
Migraine is a common, chronic disorder that affects up to 20% of the population, and women are affected up to four times more often than men with up to one third of migraine sufferers also experiencing aura.
There has long been suspected a connection between migraine and vascular events such as stroke. For this study researchers searched electronic databases and reference lists for case-control and cohort studies investigating the association between any migraine or specific migraine subtypes and cardiovascular disease. They analyzed the results of nine studies on the association between migraine, with and without aura, and cardiovascular disease. Differences in study design and quality were taken into account to minimize bias.
The study showed that migraine with aura is associated with a twofold increased risk of ischemic stroke. Further risk factors for stroke among patients with migraine are being a woman, being young, being a smoker, and using estrogen containing contraceptives. The risk was highest among young women with migraine with aura who smoke and use estrogen containing contraceptives. There was no association between migraine and heart attack or death due to cardiovascular disease.
In light of these findings, the authors recommend that young women who have migraine with aura should be strongly advised to stop smoking, and methods of birth control other than estrogen containing contraceptives should be considered. They also call for additional research to investigate the association between migraine and cardiovascular disease in more detail.
The absolute risk of stroke for most migraine patients is low, so a doubling of risk is not cause for panic, explains Elizabeth Loder from Brigham and Women’s Hospital, Boston, in an accompanying editorial. However, at a population level, this risk deserves attention because the prevalence of migraine is so high. She suggests that patients who have migraine with aura should be followed closely and treated aggressively for modifiable cardiovascular risk factors.
References:
1. Markus Schürks, et al. Migraine and cardiovascular disease: systematic review and meta-analysis. BMJ 2009;339:b3914, doi: 10.1136/bmj.b3914.
