Migraine accompanied by 'aura' linked to heart risk

CHICAGO, July 19 (Reuters) People who experience vision abnormalities before a migraine strikes are at double the risk of heart disease compared to people who do not get the debilitating headaches, a study said on Tuesday.

The ''aura'' that immediately precedes a migraine affects sufferers differently, with some combination of dizziness, flashes or spots of light, and temporary loss of vision.

Among the 28 million Americans, mostly women, who suffer migraines, fewer than one-third experience the aura beforehand that was linked in the study to the increased risk of heart attack or stroke.

Though the risk of stroke or heart problems was double among migraine suffers with aura, the problems can take a long time to appear and there are more significant risk factors such as smoking and high cholesterol, according to the five-year study of 5,125 women aged 45 or older.

''Absolute numbers mean only 18 additional cases per 10,000 women per year, so this is a rather low risk of experiencing cardiovascular disease if you have migraine with aura,'' said study author Dr. Tobias Kurth of Brigham and Women's Hospital in Boston, who published his findings in the Journal of the American Medical Association.

A common characteristic of people with cardiovascular disease and those who experience an aura before a migraine is an increased level of homocysteine in the body, an amino acid that assists in cell metabolism but which can damage the lining of blood vessels and enhance blood clotting.

Among migraine sufferers, homocysteine is only elevated in those who experience an aura, according to an accompanying editorial by Richard Lipton and Marcelo Bigal of the Albert Einstein College of Medicine.

Further investigations could look at whether medications to treat migraines might also help reduce patients' heart risk, they wrote.

REUTERS DKB RAI1032