Persons with epilepsy are more than twice as likely to develop migraine headaches as those without the disorder, according to a report published in a recent issue of Neurology.
Researchers from Columbia's School of Public Health and the Albert Einstein College of Medicine evaluated 1,947 patients with epilepsy over the age of 18, as well as 1,423 relatives of the patients, as part of the largest-ever study on the relationship between migraine and epilepsy. Results showed that more than 20 percent of people with epilepsy have migraines, compared to 11 percent of the general population. Migraine risk was highest in patients with epilepsy due to head trauma, but was significantly higher in every subgroup of epilepsy defined by seizure type, origin of the disease, age at onset and family history of epilepsy.
Because migraine is a more common condition than epilepsy, the risk of epilepsy patients developing migraine is much higher than the risk of migraine patients developing epilepsy.
"We were surprised by the strength and consistency of the relationship between migraine and epilepsy," says Ruth Ottman, associate professor of epidemiology at Columbia and lead researcher of the study. "These results indicate that risk of migraine is consistently elevated for epilepsy patients at every age and for people with all types of seizures."
According to the Neurology article, clinicians treating patients with epilepsy or migraine should be sensitive to the symptoms and familiar with the diagnostic practices for both disorders. Among the epilepsy patients who were diagnosed as having migraines on the basis of their self-reported symptoms, only 44 percent reported having been diagnosed with migraine by a physician.
"The underdiagnosis of migraine was astonishing, considering all patients in the study already were being treated by a physician for epilepsy," says Ottman. "Migraine may be overlooked because epilepsy is viewed as a more serious disorder."
"The results of this study have important implications for the treatment of migraine and epilepsy," says study co-author Richard Lipton, associate professor of neurology at Einstein. "In patients with migraine, a history of epilepsy should be sought before anti-depressants or anti-nausea drugs are prescribed as these may lower seizure thresholds. But some drugs such as Depakote work as treatments for both migraine and epilepsy, creating a therapeutic 'two-fer.'"
Migraine and epilepsy are the most common disorders that lead to neurologic consultation in the United States. A strong relationship between them has long been suspected but never before systemically demonstrated.
An estimated 23 million Americans suffer from migraine. About 11 percent have moderate to severe disabling migraine headaches that may last anywhere from a few hours to a number of days. Recurrent, pulsating pain on one or both sides of the head characterizes migraine headache, which usually is accompanied by one or more associated symptoms such as nausea, vomiting and an increased sensitivity to noise and/or bright light.
Epilepsy is a disorder of the brain brought on by recurrent, excessive, abnormal discharge of neurons. The disorder is characterized by sudden, brief attacks of altered consciousness, motor activity, sensory phenomena or inappropriate behavior. An estimated 2.5 million people in the United States have the disease.