Do Migraines Lead to Brain Damage?

Jan. 27, 2004 -- For the more than 20 million Americans who suffer from migraine headaches, the debilitating pain can cause missed workdays and lost social opportunities. But many may be surprised to learn that experts now fear migraines may also cause something far worse — brain damage.

A new study in today's Journal of the American Medical Association finds frequent migraines are associated with an increased likelihood of brain lesions. And while it is not yet known if the lesions cause further health problems, doctors say it is more evidence migraines should not be treated as simple, episodic headaches, but rather a chronic condition similar to asthma or epilepsy.

"I had no idea there might be lesions," says Debra Dolce of Crystal Lake, Ill., who has been receiving migraine treatment for more than 15 years. Keith Karasek, a migraine patient at the Diamond Headache Clinic in Chicago, Ill., concurs. "No, I haven't [heard about the lesions], and I am surprised. I will go in next week and ask [my doctor] about this."

Migraines occur when blood vessels in the brain constrict, causing pain and diminishing oxygen supply to surrounding tissue. While some kinds of migraines seem to be genetically linked, the base cause of migraines remains something of a mystery. The current theory is that migraine sufferers have a more sensitive nervous system than ordinary people do.

"We already know that migraineurs' brains tend to be different," explains Robert Kaniecki, director of the Headache Center and assistant professor of neurology at the University of Pittsburgh, Pa. "They are at increased risk for stroke and they tend to have abnormal MRIs [magnetic resonance image brain scans]."

But viewing migraines as a chronic disorder rather than an episodic one means shifting the focus of treatment from treating outbreaks of migraine with pain medication to preventing the headaches from ever occurring. Doctors hope that reducing the frequency of the migraines will reduce the damage to the brain.

Notes Dr. Joel R. Saper, director of the Michigan Head Pain and Neurological Institute in Ann Arbor: "You might have a patient who says, 'I can live with three headaches per week.' This study, if validated, means maybe they shouldn't."

More Headaches Mean More Lesions

The study examined 295 migraine patients, 161 of whom experienced migraines with aura. Auras are slight shifts in neurological function that occur just before the onset of a migraine. The sufferer may see expanding geometric shapes, feel a numb or tingling sensation or have difficulty with speech.

Doctors in the study performed MRIs on migraine patients and checked for the presence of what are called white-matter lesions and blockages of blood to the brain.

They found migraine sufferers without aura were seven times more likely to have lesions in the back of their brains as normal controls; migraine sufferers with auras were nearly 14 times more likely to have the lesions.

Frequency of migraine may contribute to the lesions. People who experienced migraines more than once a month were almost 16 times more likely to have lesions.

"If we say that progressive changes are occurring in the brain from recurring and repetitive attacks … then there's a greater burden on preventing those attacks," explains Saper.

At the time of the study, the lesions did not appear to be interfering with the subject's health or cognitive function. But more research is needed to know whether the lesions do have negative impact on health, and whether they are in fact caused by migraine attacks.

Taking Migraines Seriously

While doctors are realizing the seriousness of migraine, not all migraine sufferers are aware of the implications of their disorder. Nearly 50 percent of the migraine patients in the current study had not even been diagnosed as having migraines. Most simply believe they're suffering a headache.

Notes Kaniecki, "This study will be great to take to patients and say, 'Here's why you should take your medication and watch your diet and exercise.' … We've gotten very good at turning off migraines … The tryptan drugs (such as Imitrex) have been revolutionary."

"I treat migraine aggressively now," says Lisa Thorn, a primary care physician in West Sand Lake, N.Y., "But if the brain damage theory is proven, I think I could convince more patients to use prophylactic medication. Most sufferers do not want to take something every day … but might reconsider if they know their brain function long-term is affected."

Other doctors are leery of suggesting more drugs. Jeff Susman, primary care physician and the director of academic medicine at the University of Cincinnati, Ohio, believes the current study supports an aggressive approach to treating migraine, but he adds, "The challenge is to separate pharma hype from reality."

Is There a Cure? No, Say Some

Preventing migraines remains more problematic. Doctors use calcium channel blockers, beta blockers (like those used to treat heart problems) and anti-seizure medication to try to "quiet" the overactive nervous system.

Explains Saper, "There is a range, and treatment must be individualized. What gives one person 70 percent reduction in headaches may only provide a 20 percent reduction for another."

But Kaniecki acknowledges: "My theory is that there is no cure for migraines. I think the nervous system of a migraine sufferer represents a kind of variation in the population that is not going to be eliminated."

Still, doctors agree prevention of migraines is optimal both for increasing the sufferer's quality of life and possibly averting brain damage. "The more [headaches] you have, the more you get," Saper notes. Doctors are optimistic studies like this one will help provide the knowledge to break the migraine cycle.