Does Migraine With Aura Have An Increased Risk Of Stroke?
Does Migraine With Aura Have An Increased Risk Of Stroke?
Migraine is a genetic, inherited condition involving the brain, the trigeminal nerve, and cranial blood vessels which consists of symptoms of episodic headache with intervening periods of normal health.
Twenty-five % of women have migraine at age 42 and six % of men at age 37.
The three most painful human medical conditions are childbirth, kidney stone, and migraine headache. Migraine is the fifth most common disabling medical condition and the tenth most common cause for a visit to the emergency room. For women migraine is their most common chronic medical problem, more prevalent than heart disease, hypertension, diabetes, or arthritis.
Migraine without aura (previously known as common migraine), has attacks that are usually severe, one-sided, throbbing, and associated with nausea, vomiting, or sensitivity to light, sound, or movement. The pain of a migraine is above 5 on a 5-10 scale. Many patients say to me in my office that their headaches are a “twenty” when asked about a 1-10 scale.
When untreated, these attacks typically last 4-72 hours. A combination of features is required for the diagnosis, but not all features are present in every attack or in every patient. These symptoms distinguish migraine from tension-type headache, the most common type of headache. Tension Type Headache is 70 % of headache and relates to the anxiety disorders, while migraine is 30 % of headache.
Tension Type Headache is usually bilateral, described as “tight or pressure” and may only be mild or moderate. It should be less than 5 on a 1-10 pain scale. Any severe and recurrent headache is most likely to be a form of migraine and to be responsive to anti-migraine therapy.
Migraine with aura (MA), present in 15 percent of migraine patients, attacks are usually preceded or accompanied by transient focal neurologic symptoms, which are usually visual; such patients have migraine with aura (previously known as classic migraine). MA used to be called “classic migraine.” Transient migraine aura visual symptoms may be positive, such as seeing black and white or colored zig-zag shaped images that flash and move or negative such as seeing a blank spot (scotoma) or only half of things.
Non-visual aura symptoms may be numbness spreading from fingers to hand to cheek, or trouble talking. The difficulty talking is called aphasia and may be blocked speech, or trouble naming things.
The aura symptoms characteristically come 30 minutes before the headache starts, although some persons have the aura in the middle or the end of the headache. At least one aura symptom develops gradually over 5 minutes and/or different aura symptoms occur in succession over 5 minutes. Each symptom lasts 5 or 60 minutes.
In a recent large, population-based study, 64 percent of patients with migraine had only migraine without aura, 18 percent had only migraine with aura, and 13 percent had both types of migraine (the remaining 5% had aura without headache).
Does Migraine With Aura Have An Increased Risk Of Stroke? Yes, all research studies reveal an increased risk of stroke for migraine with aura. The risk is highest in women less than 45 years old who smoke cigarettes and are on estrogen based birth control pills.
Since World War II there have been 2 large data centers studying stroke and heart disease. One of them is at the Mayo Clinic in Rochester, Minnesota and the other is in Framingham, Massachusets where the studies are performed at Harvard Medical School. Every doctor has learned to respect Framingham data and Framingham data reveals a 6 % risk of stroke in MA patients.
What kind of strokes occur with migraine with aura?
The usual type of stroke that occurs with migraine without aura is an “ischemic stroke,” as opposed to a hemorrhagic stroke. Ischemia means “lack of blood” either from a closed artery, called a “thrombus” or from a small blood clot, called an, “embolus.”
Thrombosis. An example of a thrombosed artery would be blockage of the left carotid artery in the neck, which leads from the heart to the brain. Then with closure of the left carotid artery, part of the left brain will be deprived of blood and will be ischemic and cause an infarct (dead brain tissue). This would be called a cerebral infarct.
Emboli. Emboli are usually formed in the heart in patients who have atrial fibrillation, an irregular heart beat where the top part of the heart, the atrium, doesn’t contract. This allows blood to sludge and form a clot which then drops down into the lower part of the heart, the ventricle. Then the ventricle contracts and shoots the clot into the brain. Severe, large strokes can occur from atrial fibrillation.
Hemorrhage. Hemorrhagic strokes are rarer with migraine and are usually more severe and deadly than ischemic strokes. Hemorrhage comes when arterial blood at high pressure, being pumped by the heart, is released into the brain through a defect in the arterial wall.
Why does cigarette smoking have an increased risk of stroke for migraine with aura persons? Cigarette smoking is a terrible health risk habit. Nicotine is a very addictive drug and almost as addictive as cocaine. Also, the cigarette smoke and burned ash byproducts produce cancer and lead to an increased risk of the development of atherosclerosis.
Athero means “fat” and sclerosis means “hard.” The American Heart Association has strongly declared that cigarette smoking worsens atherosclerosis and increases the risk of stroke and heart attack. Cigarette smoking is listed as a risk factor for stroke.
Why do estrogen based birth control pills increase the stroke rate for women with migraine with aura? The worst combination of stroke risk factors are a woman with migraine with aura, who is aged less than 45 years old, who takes an estrogen based birth control pill, and who smokes.
Estrogen based birth control pills aggravate stroke in MA patients by increasing their blood pressure and making blood hypercoaguable (more likely to clot).
Estrogen based birth control pills also may aggravate or drive migraine attacks, cause abortion, and increase the risk of breast cancer.
Are there other reasons for stroke with migraine with aura? Yes, migraine with aura is also associated with:
Patent foramen ovale
Arterial dissection of cervical arteries
Reports of polymorphism
Decreased resistance to activated protein C
Protein S deficiency
Antibodyphospholipid antibody syndromes
This is a large group of rare associated conditions which migraine with aura and stroke share. Migrainous infarction is the occurrence of a CAT scan or MRI scan proven acute stroke that occurs during a migraine with aura attack.
Patent foramen ovale is a controversial relationship between migraine with aura and a small hole in the heart left over in some persons from the circulation their heart had with their mother in her womb. It has been studied extensively as to whether surgical closure would be helpful and the result is to not do surgery for this condition.
Rarely migraine with and without aura are associated with a tear in the inside of the carotid artery, a condition called arterial dissection. Dissection can result from unusual neck positions such as turning the head far to one side. It can occur during chiropractic neck manipulation.
What can be done to prevent stroke in persons with migraine with aura? All are called to follow the American Heart Association’s recommended lifestyle:
1.Genetic link to atherosclerosis. All that can be done here is to be aware of familial risk factors for atherosclerosis and work on treating or avoiding them.
2.Exercise aerobically 3-4 days a week for 20-30 minutes. Aerobic exercise increases the heart rate. Good examples of aerobic exercise are jogging, swimming, stationary bicycle, rowing, Jane Fonda type group exercise, and an elliptical machine.
5.Lower cholesterol and lipids.
7. Maintain a reasonable weight.
8.And for migraine with aura patients, don’t take estrogen-based birth control pills.
Good luck with this.
Britt Talley Daniel MD