From December 2003/January 2004

A migraine is not just a headache

By GAIL ZIMMERMAN, Contributing Writer

Migraine is a disease, of which the pounding headaches are just one symptom. Migraine disease affects between 11 and 18 million Americans, mostly women, according to MAGNUM (Migraine Awareness Group: A National Understanding for Migraineurs). "Although statistics indicate that 18 percent of women and six and a half percent of men suffer nationally from migraine, that’s probably an underestimation," says Dr. Robert Shapiro, assistant professor of neurology at the University of Vermont, attending physician at Fletcher Allen Healthcare in Burlington, VT and consulting neurologist at Alice Hyde Hospital in Malone, NY.

Indeed, migraine disease is often misdiagnosed. According to MAGNUM, as many as 60 percent of men and 70 percent of women who suffer from migraine have never been diagnosed. "Migraine is a clinical diagnosis based on what the patient describes," explains Dr. William Pelton, general internist at Champlain Valley Physicians Hospital Medical Center in Plattsburgh.

Migraine pain is associated with vasodilation in the extra cerebral cranial blood vessels (expansion of the blood vessels), which is why the medication generally used to treat headaches can dilate the blood vessels, making migraine pain worse, according to MAGNUM. Migraine, a neurological disorder, is characterized by inflammation of the tissue surrounding the brain. "Migraine is a brain disorder that has variable symptoms that can affect many parts of the body. Although headache is the most common symptom, migraine can occur without headache," explains Shapiro. Associated symptoms may include nausea, vomiting, sensitivity to light, sound or smells, numbness, difficulty with speech or motor skills, vertigo (a false sense of movement), auras (visual disturbances moving across the visual field) and severe headache. The headache tends to be unilateral, affecting one side of the head and lasting from a couple of hours to a couple of days, and the throbbing pain associated with it may be mild, moderate or devastating, according to Pelton. "Migraine disorder is very personal, very individual. Each person who has it has a different experience with it. It doesn’t fit neatly into a box. Doctors need to be aware that patient descriptions will have these variabilities," Shapiro says.

There is no clear reason why one person has migraine disease and another doesn’t. "We’re not sure about the cause of migraines. We know migraine starts in sites deep in the brain, firing off inappropriate messages which spread across the brain," explains Pelton. Approximately four percent of adults experience chronic daily migraine headaches, which occur more than 15 days out of the month and last at least four hours at a time, according to Shapiro. A genetically based disease, the risk of a child developing migraine increases when one or both parents have it. "Probably anybody has the capacity to have a migraine under the right conditions," Shapiro says.

Hormonal factors play a role in migraine disease, which may explain why women are three times more likely to suffer from migraine. People with irregular meal times and those with sleep problems such as sleep apnea, narcolepsy or other conditions, which disrupt sleep significantly, are more prone to migraine, according to Shapiro. People with psychiatric disorders, especially depression and anxiety, those who suffer from asthma, seizure or stroke and those with fibromyalgia or chronic fatigue syndrome are also more likely to be migraine sufferers. "These medical conditions that are more likely to occur in patients with migraine give us clues to the causes of migraine," Shapiro explains. Migraine and epileptic seizure disorder are also interrelated, with migraine affecting up to 15 percent of people with epilepsy, according to MAGNUM.

Generally, there are three main types of migraine disease: migraine with aura, migraine without aura and hemiplegic migraine, which is very rare. "Hemiplegic migraine is characterized by a frank paralysis on one side of the body or a loss of strength on one side of the body during the migraine. It runs in families, but is very uncommon," Shapiro says.

Migraine with aura sufferers experience a gradual onset of visual aura before or during the headache. It may appear as spots , colors,

dots or flashes of light that move gradually across the field of vision, usually but not always affecting both eyes. Auras generally last less than 30minutes, but can last longer in some cases. It is also possible to experience migraine without headaches, according to Shapiro. "The headache is just one piece of the whole process of what happens. It occurs in most people who have migraine, but other symptoms can occur without headache. Other symptoms of migraine are often neglected because headache symptoms are what patients are most focused on," Shapiro adds. He advises people who experience visual auras in the absence of other symptoms to inform their physicians. "Visual auras by themselves almost always justify a closer look. If they are repetitive and predictable, there is a greater likelihood that they are migraines rather than something else," Shapiro says.

Migraine without aura is the most common type. In adults, migraine generally lasts four to 72 hours if left untreated. In children and adolescents, migraine typically lasts less than four hours. "Kids often don’t have attacks with commonly seen symptoms. Their symptoms are more unusual, and may include cyclical vomiting," Shapiro explains.

The onset of migraine often occurs in childhood. About 20 percent experience migraine before the age of 10, and 45 percent before the age of 20, according to MAGNUM. Until puberty, migraine is as prevalent among boys as it is among girls, but after puberty, prevalence among girls increases threefold. According to MAGNUM, clinical studies indicate that motion sickness affects 45 percent of children with migraine and sleepwalking affects 28 percent. Children are also more likely than adults to find relief from migraine by napping, Shapiro notes.

Often, people suffering from migraine experience a change in thinking patterns. "People don’t communicate or understand as well when experiencing a migraine. Patients have described it as having a cloud over them. The most disabling part of migraine might be invisible: this change in clarity of thinking," Shapiro says.

Certain conditions can trigger migraine to occur. Weather patterns affect migraine. According to MAGNUM, a drop in barometric pressure combined with the passing of a warm front, high temperature, humidity and often rain, can trigger a migraine attack. Wind from the southeast as well as extreme changes in barometric pressure have also been cited as migraine triggers. "Patients are often able to predict weather changes based on the onset of a migraine but we don’t really understand why," Shapiro says.

Menstruation can also trigger migraine, which appears to be associated with falling levels of estrogen. Bright light, chemical smells including colognes and gasoline, smoke, stress, lack of sleep, red wine, beer, peanut butter, foods that act as vasodilators such as fish, aged cheese, some chocolate and MSG. Caffeine may also trigger migraine, according to Shapiro. "About 85 percent of Americans consume caffeine daily. Fifty percent have more than the equivalent of three cups of coffee a day. The relationship between caffeine and migraine has not been fully explored yet, but it’s interesting that many of the medications used to treat migraine contain caffeine," Shapiro says.

Overuse of substances that relieve migraine can likely lower the threshold to trigger migraine attacks in the future. "When some medications are used as often as three times a week, patients may see a gradual shift from episodic migraine to chronic migraine, although it may take years for the disease to become chronic," Shapiro explains.

Although the identification of triggers can help patients predict the onset of an attack, allowing them to either avoid migraine or treat it more quickly, resulting in a shorter, less intensive attack, identifying triggers is not always easy to do. "It’s hard to nail down significant triggers, since migraine is so variable between individuals and even between attacks in the same individual," Shapiro adds.