The lessons on migraine headaches leave some people wanting to learn more.

Medicines for treating migraine pain or preventing migraine attacks are improving all the time. But a series of small studies has opened new debate on whether migraine may be more than just a painful experience, at least for some patients.

Migraine, some researchers say, is triggering ischemic mini-strokes (small blood blockages in the brain) for certain sufferers. This, doctors suggest, means migraine may add up to a chronic progressive disease, each attack pointing toward an eventual critical mass.

Migraine is considered a vascular headache because it is associated with changes in the size of the arteries in and outside of the brain.

The purported link between migraine and apparent mini-strokes is particularly pronounced for victims whose attacks coincide with an aura spots or lines before their eyes though patients without aura are not always immune. Interestingly, this same aura phenomenon was observed in another study linking migraine attacks with chest pain mimicking that of a heart attack.

The chest pain, however, was not a sign of heart disease. Nor did the mini-strokes cause the classic symptoms of a stroke. They were what doctors call sub clinical real, as confirmed by sensitive MRI scans but without overt effects. What worries the neurologists is that the minor brain damage caused by enough of these sub clinical migraine-triggered events might accumulate over time to result in serious trouble.

Migraine should be conceptualized not just as an episodic disorder but as a chronic-episodic and sometimes chronic progressive disorder, wrote Drs. Richard B. Lipton and Jullie Pan of the Albert Einstein College of Medicine in New York City in an editorial in the Journal of the American Medical Association.

Under this paradigm, they added, the goals of treatment may shift. Instead of merely relieving pain and restoring patients’ ability to function, there could also be a need to prevent migraine disease progression. Researchers don’t believe that all migraineurs are at risk of these mini-strokes, and they are trying to pinpoint the subgroup that is most sensitive for special attention.

The Einstein team was commenting on a Dutch study in the medical journal that looked at 60 brain infarcts detected in 31 migraneurs. The study concluded that patients with migraine in the general population are at increased risk of these sub clinical mini-strokes, particularly lesions located in the posterior cerebellum.

Patients with migraine with aura and a high attack frequency were at greatest risk. In addition, women, but not men, with migraine with and without aura were at increased risk of deep white matter lesions, and this risk also increased with the frequency of each attack.

White matter damage is probably the result of even brief blood blockages, temporary low blood sugar, hypoglycemia, energy deprivation, oxidative stress, or platelet clumping.

Whether this all boils down to a significant finding is not yet clear. Why only women and not men should be at increased risk for white matter lesions is not known, but this finding is consistent with women being at increased risk for stroke, the Dutch authors wrote.

Meanwhile, a subsequent analysis of 14 studies in the medical literature found that the risk of ischemic stroke was more than twice as great for migraineurs as it was for people who don’t have migraine. And if it turns out that reducing the frequency of migraine attacks is a viable approach to preventing the accumulation of brain damage, there is always surgery.

In the January 2005 issue of Plastic and Reconstructive Surgery, a study found that patients can be injected with Botox to determine which muscles in their forehead or back of their head triggered their migraines. Once the muscles are pinpointed, they can be surgically removed.

The surgery eliminated migraines in 35 percent of the patients and reduced the frequency, intensity or duration of migraines in 92 percent.

SOURCES: January 2005 Plastic and Reconstructive Surgery; Jan. 28, 2004, Journal of the American Medical Association; Dec. 30, 2004 British Medical Journal