People who have migraines are twice as likely to have a stroke as others, researchers say.
Experts in Canada and the US looked at 14 studies that had shown a link to quantify the exact risk involved.
Migraines roughly doubled the stroke risk, while migraines with ‘auras’ more so than those without interruptions to the sufferers’ vision.
Women with migraines who were on the oral contraceptive pill appeared to be at particular risk, reserach found.
The increased risk of stroke is probably down to the reduced blood flow to the brain which usually occurs in a migraine, the researchers believe.
The studies looked at by Dr Ali Samii, neurologist at the University of Washington, and his colleagues, suggest the risk of stroke for migraine sufferers is 2.16 times that for non-sufferers.