In this condition factsheet:
The Facts on Migraine
In North America, more than 1 in 10 people have migraine headaches. Most migraine sufferers are women. Migraines usually appear between the ages of 10 and 40. After the age of 50, they tend to disappear, especially among women after menopause.
Causes of Migraine
Migraine is a complex disorder involving the brain and the blood vessels around the brain and head. The brain may become hyperactive in response to certain environmental triggers, such as light or smells, for reasons that are not known. This starts a series of chemical changes that irritate the pain sensing nerves around the head and cause blood vessels to expand and leak chemicals which further irritate the nerves.
While migraine does seem to run in families, a clear genetic cause has only been nailed down for one rare type of the disease called familial hemiplegic migraine.
Although we don't know the precise causes of migraine, we are aware of potential triggers – habits and circumstances that are associated with the onset of a migraine headache.
The number one trigger is hormonal changes. Two-thirds of women sufferers only get their headaches around the time of their period. Migraines in women are usually worse around puberty and they tend to disappear around menopause.
Another common migraine trigger involves food. The most common culprits are:
- alcohol, especially red wine and beer
- aged cheeses
- fermented, pickled, or marinated foods
- monosodium glutamate (MSG)
Other triggers include:
- changes in sleeping patterns
- changes in barometric pressure
Symptoms and Complications of Migraine
Migraine headaches are more severe and last longer than regular "tension" headaches. The pain is more localized, often concentrated over one eye. Severe headaches that affect only one side of the head are generally due to migraines. Migraine headaches are often associated with nausea and vomiting as well as hypersensitivity to light and noise. The headaches are often made worse by movement or bending over. As a result, migraine sufferers tend to lie still in a dark, quiet room and avoid any type of stimulation.
About 1 in 5 migraine sufferer experiences an "aura" just before the headache comes on. Auras are visual effects that can include flashes of light, lines with vivid colours, or double vision. Occasionally patients may feel weak or slur their words. These symptoms usually disappear after 15 to 30 minutes, only to be replaced by crushing pain and, in some cases, severe nausea.
Migraine headaches should not be confused with rebound headaches (also called medication overuse headaches). Rebound headaches can strike anyone who uses ASA* (acetylsalicylic acid) or other simple pain medications (such as acetaminophen or ibuprofen) for headache pain on more than 15 days a month. They can also occur for people who use narcotic pain relievers (e.g., codeine), medications containing more than one pain reliever, or "triptan" medications (e.g., almotriptan, rizatripan, sumatriptan) on more than 10 days a month. Sometimes these rebound headaches are called medication-induced headaches. The medicine works for a little while, but as it wears off, the pain comes back with a vengeance. If you turn to pain medications for relief, the vicious cycle often continues. The end result is a constant dull headache, affecting both sides of the head. It tends to worsen each time the pain medication wears off. If you think you might have rebound headaches, talk to your doctor about the best way to manage them.
A long-term study suggested that women with migraine have a higher risk of stroke. Migraine generally affects young people, and stroke is rare in this population. The relationship between migraine and stroke is still unclear and further studies are needed.