Migraine a risk factor for stroke?

WE USED to think that migraine is a bothersome but otherwise benign type of headache. Recent data suggest that it may not really be as harmless as it was believed to be.

Two weeks ago, I joined around 20 Filipino heart specialists who attended an international congress on the treatment of hypertension and its complications like stroke and heart attack in Milan, Italy. One interesting topic discussed was the link between migraine and stroke. An expert reported an accumulating evidence suggesting that migraine might be a risk factor for cardiovascular disease or, more specifically, stroke.

Dr. Enrico Agabiti-Rosei from the University of Brescia in Italy, presented the findings of their published study, which showed that patients with both hypertension and migraine headaches had a higher probability of a history of stroke than patients with high BP but no migraine.

Clinically rare

“The prevalence of hypertension and migraine comorbidity is clinically rare, but doctors should pay attention when they see this, because it might help identify patients at risk of an event. Migraine might be considered as a factor to be included in the score for risk of stroke,” Dr. Rosei proposed.

He recommended that when a physician sees a young patient with hypertension, he should find out if there is migraine as well, since when the two medical problems occur together, “it’s very important to make an appropriate screening of cardiovascular risk factors, because what a doctor can do is try to reduce as much as possible these risk factors that are correctable by treatment—this includes not only hypertension but also high cholesterol, diabetes and so on.”

According to Dr. Rosei, migraine could be associated with a malfunction of the arteries, referred to by doctors as endothelial dysfunction. This is the initial step that leads to the progressing narrowing of arteries hampering the circulation. So when one presents with both hypertension and migraine, this should be a red flag to the physician to be a little more aggressive in treating that patient because of the increased risk of stroke. And these usually are relatively young patients in their 40s.

Initial warning symptom

In a previous research work, it was suggested that migraine with initial warning symptoms called “aura” compared to migraine without aura has shown the greatest link with cardiovascular problems including stroke.

In their study, Dr. Rosei and his colleagues included 2,973 patients with hypertension, migraine, or both. Of the group, 517 or 17 percent suffered from hypertension-migraine combination, while 1,271 or 43 percent had hypertension only, and 1,185 or 40 percent were noted to have migraine only.

According to Dr. Rosei, in those with both conditions, the onset of complications including stroke occurred at about 45 years of age, with migraine starting significantly later than in the migraine-only group, and hypertension significantly earlier than in the hypertension-only group. Blood pressure control was also more problematic in those with both conditions, requiring more drugs at higher dosages to bring down the BP. A positive family history for both migraine and hypertension was also noted in this group of  patients with migraine and hypertension together.

Dr. Rosei presented that the migraine plus hypertension group had a higher risk for stroke, compared with those with hypertension only, and those with migraine alone. In the age range of 40 to 49 years, the risk of stroke was five-fold greater compared to those with hypertension alone.

The exact cause of migraine is not fully understood, but it’s believed to be due to hormonal factors, i.e. substances being naturally produced in the brain. Hyperproduction of these substances leads to swelling of the blood vessels in the brain. The inflamed vessels press on nearby nerves, hence the throbbing headache.

Avoiding ‘triggers’

Migraine sufferers are advised to avoid “triggers” which could provoke an attack and these include:

Sleep disturbances, either lack of or too much of it;

Hunger, especially when meals are skipped;

Bright lights, loud noises, or strong odors;

Stress and anxiety;

Alcohol;

Too much caffeine and its sudden withdrawal;

Seasoning such as monosodium glutamate (MSG);

Foods with tyramine, such as aged cheeses, smoked fish and Chianti wine;

Low-calorie sweeteners containing aspartame.

So for migraine sufferers, it would be best to check the BP regularly, quit smoking for those who smoke, and maintain a health-promoting lifestyle. This is one’s best bet to neutralize the relatively increased risk of developing a stroke at a later date.