Men who experience migraine headaches are more likely to suffer heart attacks, US scientists claim.
The study, conducted by staff at the Harvard Medical School and at Brigham and Women's hospital in Boston, drew its conclusions from a sample of more than 20,000 men without a previous history of heart disease studied over a 21-year period.
Major cardiovascular disease was experienced 8.5 times per 10,000 men per year for those without migraine problems, compared with 10.4 per cent for those who did suffer from migraines.
This "significantly increased" risk of cardiovascular disease and heart attacks could be caused by a number of factors, the study suggests.
It may be that migraines are a side-effect of a larger problem, as those with an increased body-mass index are more likely to suffer migraines and heart attacks.
Alternatively migraines may act as a marker of the increased risk by warning of the build-up of plaque on the arteries.
But the scientists sought to play down these alternative theories, insisting that "the increased risk of vascular events remained after controlling for major cardiovascular risk factors in the present data and other studies".
"In this large prospective cohort of apparently healthy middle-aged men, migraine was associated with increased risk of subsequent major cardiovascular disease, which was driven by increased risk of myocardial infarction [heart attacks]," the study concludes.
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