Women over 45 who experience visual symptoms known as 'aura' prior to the onset of a migraine headache are more likely to suffer from cardiovascular problems, new research has found.

An aura can appear about 10 to 30 minutes prior to onset of the characteristically excruciating migraine headache. It may take the form of bright lights shimmering around objects. Some people see zig-zag lines or wavy images. Parts of objects may vanish and then reappear. Some sufferers even experience temporary blindness.

Low Risk of Death Overall

Researchers at Brigham and Women's Hospital, led by Dr. Tobias Kurth, evaluated data on 28,000 women, all aged over 45, from the Women's Health Study. They found that those who experienced migraines with aura were at roughly twice the risk of having a heart attack or major cardiovascular disease, and twice as likely to experience ischemic stroke, as those who never had migraines.

The women who had migraines without aura were at no higher risk than those who never had migraines.

While the results suggest that women who have aura migraines should be extra vigilant about maintaining healthy blood pressure and cholesterol levels, the researchers emphasized that the overall risk of death in the study was low -- only 130 women out of 28,000 died in a 10-year period.

Migraines are much more common in women than in men, affecting about one in every six women, versus one in every 15 men. Although the most common symptom is a debilitating headache, some migraine sufferers also experience nausea, vomiting, and sensitivity to light or noise.

The researchers could not explain the apparent link between migraines with aura and heart risk, but they hypothesized that it might be genetic.

Potential Conflicts of Interest?

The study may bring on another headache for the journal that published it.

According to press reports, Dr. Kurth and the other five authors of the study have all received research funds from companies that make treatments for migraines or heart problems or have worked as consultants for such firms. They did not report their financial ties to JAMA, however, which recently enacted a tougher policy about the need for such disclosures.

After the connections were uncovered by The Associated Press, the authors reportedly responded that they did not believe they were relevant to the study, because they were not suggesting or endorsing any form of treatment as a result of their findings.

"We'll get killed [in the media]," JAMA editor in chief Dr. Catherine DeAngelis was quoted as saying.