Migraine and Stroke

Patients with migraines who develop auras may have symptoms similar to a stroke.

Migraines and strokes can share similar neurological symptoms, yet they require very different responses. Migraines often improve with rest and pain management, whereas strokes demand immediate medical intervention to prevent permanent brain damage.

Patients with a history of migraines usually recognize a familiar pattern of their symptoms. They need to be aware of changes to that pattern and symptoms.

A migraine consists of a constellation of neurological signs—most notably an intense, pulsating headache that often strikes one side of the head. This condition is a neurologic disorder in which external factors, such as stress or insufficient rest, trigger a wave of neuronal activity (known as cortical spreading depression) in the brain, leading to severe pain and other accompanying symptoms.

The pain typically throbs and may be confined to one hemisphere, though it can spread to both sides. It is frequently accompanied by nausea, vomiting, and heightened sensitivity to light and noise. During an attack, most sufferers become incapacitated and seek refuge in a dark, quiet space until the pain subsides, which can take anywhere from a few hours to several days.

Importantly, migraine is more than just an intense headache; it's a clinical diagnosis based on a specific pattern of symptoms.

Aura describes sensory disturbances that occur just before or during the onset of a migraine headache and last no more than an hour. There may be changes in vision, smell, taste, and speech, among other symptoms. The aura symptoms may be unilateral (uni=one + lateral=side) affecting one side of the body, or bilateral (bi=both + lateral=side). Sometimes patients can experience the aura without the headache.

Examples of aura symptoms include the following:

• Visual disturbances are most common. The patient may notice flickering lights, bright zigzag lines, shimmering stars or spots, or crescent-shaped blind spots (scotomas). There can even be temporary partial loss of vision.
• Sensory changes may include pins and needles tingling paresthesia (para=irregular + aesthesia=sensation). Often, they may start in the hand, spread up the arm, and then may affect the face, especially the nose and mouth on the same side of the body.
• Speech difficulties are a classic symptom that is often described, but they are less common than vision or sensation changes.
• Other less common auras include muscle weakness on one side of the body, vertigo, and changes in sense of smell.

A key feature distinguishing aura from other conditions, like a stroke, is that the symptoms of aura increase or build up over several minutes, usually at least 5 minutes, and can spread or change location. The visual disturbance expands from the center of the visual field outward, or the numbness and tingling marches up the arm.

A stroke (cerebrovascular accident or CVA) is a sudden interruption of blood flow to a specific region of the brain, which immediately deprives tissue of oxygen and other essential nutrients, resulting in rapid brain cell death within minutes.

There are two main types of stroke:

• Ischemic strokes are caused by a blood clot blocking a brain artery, preventing blood flow to part of the brain. The clot can form at the site of the blockage (thrombus), or it can travel to the brain from another part of the body (embolus). In patients with atrial fibrillation, a blood clot can form in the heart and embolize to the brain to cause a stroke. Narrowed carotid arteries in the neck are also places where clots can form and then travel to the brain.
• Hemorrhagic strokes describe strokes where there is bleeding into brain tissue caused by the rupture of a weakened blood vessel, leading to bleeding into or around the brain tissue. Common reasons for brain bleeding include uncontrolled high blood pressure, abnormal or weakened blood vessels (aneurysms, arteriovenous malformations), or blood clotting issues including the use of prescription blood thinners.

Both types of stroke result in an immediate loss of blood supply to part of the brain, and that causes sudden loss of function in the specific area of the brain that is damaged.

Common symptoms include weakness or paralysis often on one side of the body, severe confusion, difficulty speaking or understanding speech, sudden decrease or loss of vision, and loss of coordination or balance. Patients with hemorrhagic stroke with bleeding in the brain usually develop an abrupt onset, intense headache.

In migraine patients who have not experienced a previous migraine aura, it may appear as if they are suffering a stroke.

Strokes are medical emergencies, and it is reasonable to activate emergency medical services and seek medical help.

Brain cells die rapidly without oxygen. Stroke is a medical emergency, and immediate treatment is crucial to minimize permanent brain damage that may result in disability or death. Time to treatment is often measured in minutes.

The term "brain attack" is used to describe a stroke so that people who understand heart attack will respond with the same urgency.

Patients with migraines who develop auras may have symptoms similar to a stroke.

Unless the patient knows with certainty that they are having their "regular" migraine, it is reasonable to seek emergency care immediately if concern for a stroke exists.

Migraines with aura do not directly cause strokes, but they are an independent risk factor for ischemic stroke. This usually occurs in women under the age of 45. The use of tobacco products and oral contraceptives may increase the risk.

It is thought that a very long-lasting aura, in association with cortical spreading depression (the mechanism of migraines), leaves part of the brain with prolonged decreased blood supply that results in a stroke.

Stroke and migraine with aura partially share pathways in how they develop and cause their symptoms. They both involve abnormal nerve and artery interactions, cortical spreading depression (CSD), and endothelial dysfunction (blood vessel wall abnormalities), though they each have different final mechanisms to produce their symptoms. Migraine patients at highest risk for stroke are those who also have the risk factors of high blood pressure, high cholesterol, diabetes, smoking, and obesity.

Migraine triggers and causes

Researchers are continuing to learn about the cause of migraine headache. The pathway to develop a migraine headache is thought to be as follows:

• The patient who develops migraines is already sensitized, perhaps by genetic predisposition, since migraines often run in families.
• A trigger like stress, lack of sleep, or hormonal changes of serotonin levels in the brain causes development of cortical spreading depression (CSD), or an electrical slow wave that may temporarily shut down brain cells.
• This is brain silencing or an aura that in some patients leads to sensory changes like visual changes or one-sided weakness.
• CSD causes inflammation and irritation of the trigeminovascular system. The trigeminal nerve carries pain signals, and the blood vessels are located in the protective layers that line the brain.
• The inflamed trigeminal nerve releases the chemical CGRP (calcitonin gene-related peptide), which causes blood vessels to swell and to leak, resulting in the throbbing headache associated with symptoms of nausea, vomiting, and light sensitivity.
• The swollen vessels may continue to irritate the nerve, causing a vicious cycle, releasing more CGRP, more swelling and pain, and causing a headache that persists.

The top migraine triggers include the following:

• Stress increases some brain chemicals irritating nerves
• Hormone changes in women
• Not eating
• Weather changes
• Sleep disturbances affect serotonin levels in the brain
• Bright or flickering lights may overstimulate the brain causing CSD
• Alcohol
• Food

Stroke causes

A stroke or CVA is a sudden interruption of blood flow to a specific region of the brain, which immediately deprives tissue of oxygen and other essential nutrients, resulting in rapid brain cell death within minutes. It is either ischemic, caused by a blood clot blocking an artery in the brain, or hemorrhagic, where there is bleeding within the brain tissue.

BEFAST is the acronym used to remember when to worry about a stroke:

• B - Balance: Sudden loss of balance or coordination
• E - Eyes: Sudden blurred, double, or loss of vision in one or both eyes
• F - Face: Sudden drooping on one side of the face, difficulty smiling, or trouble speaking
• A - Arm: Sudden weakness or numbness in one arm
• S - Speech: Sudden difficulty speaking, slurred speech, or trouble understanding speech
• T - Time: There is only a short period of time where treatment may be offered to try and reverse the symptoms of a stroke. Call 911 immediately if these symptoms are present and there is concern for stroke