What Causes Migraines?

The exact cause of migraines remains a mystery. However, several factors are associated with migraines.

A migraine is a complex disorder that involves episodes of recurrent and severe headaches. A migraine headache is usually on one side and may be associated with visual or sensory symptoms, collectively called aura. The aura may occur before, during or after a headache.

An episode of a migraine can be very painful, lasting for hours, making day-to-day activities difficult until the episode is resolved. Women are more likely to suffer from migraines than men.

Migraines are not felt the same way by everyone. The usual symptoms of a migraine are:

• A severe, throbbing headache that increases with movement.
• Pain is usually limited to one side of the head, around the forehead and around the eyes. However, it can be felt anywhere around the head or neck.
• Pain builds up between one to two hours, progressively increasing and becoming more diffuse.
• A migraine headache can last for four hours to three days.
• Nausea occurs in 80% of the cases.
• Almost half of the people with a migraine complain of vomiting.
• Loss of appetite.
• Light-headedness.
• Sensitivity or discomfort to light and sound.

The typical features of a migraine aura are:

• Aura can occur before, during or after the onset of a headache.
• An aura can also occur independently, with no relation to the headache.
• An aura usually builds up over five to 20 minutes and lasts less than an hour.
• Most commonly, visual symptoms occur during the aura. The person may report seeing flashes of light, colorful or bright shapes, shimmering spots, or loss of vision.
• Hearing various kinds of sound.
• Difficulty talking.
• Weakness or numbness of the face or one side of the body.

The exact cause of migraines remains a mystery. However, several factors are associated with migraines. Some of the factors are:

• Migraines happen due to changes in the blood supply to the brain accompanied by inflammation, according to the neurovascular theory.
• Migraines may be due to changes in the level of a chemical in the brain called serotonin. Low levels of serotonin cause the vessels that supply blood to the brain to swell up. This leads to pain and other symptoms of a migraine.
• Genes also play a role in causing migraines. Around 70% of migraine patients report their parents, grandparents or siblings suffer from migraines.
• The higher occurrence of migraines in women suggests the role of hormones in causing migraines.

Other factors causing migraine events are:

• Stress
• Excessive or insufficient sleep
• Medications (e.g., contraceptives)
• Smoking
• Exposure to bright or fluorescent lighting
• Strong odors (e.g., perfumes, colognes, petroleum distillates)
• Head injury
• Weather changes
• Motion sickness
• Cold stimulus (e.g., ice cream headaches)
• Lack of exercise
• Fasting or skipping meals
• Red wine
• Certain foods and food additives (e.g., caffeine, artificial sweeteners, monosodium glutamate (MSG), citrus fruits, aged cheese, meats with nitrites)

A migraine is a long-term condition that can interfere with day-to-day activities but is typically not otherwise dangerous to organs. However, some studies have shown that, although rare, migraines can cause strokes in people, especially in women. Patients are completely symptom-free between attacks. Patients with migraines have even reported being migraine-free for years.

The frequency and severity of migraine attacks tend to decline with age. Around one-third of migraine sufferers stop having migraine attacks after around 15 years.