New clues to the headache disorder are leading to potent treatments with fewer side-effects, says Jane E. Brody
Although my migraines were not nearly as bad as those that afflict many others, they took a toll on my work, family life and recreation. Atypically, they were not accompanied by nausea or neck pain, nor did I have to retreat to a dark, soundless room and lie motionless until they abated. But they were not just "bad headaches" - the pain was life-disrupting, forcing me to remain as still as possible.
Despite being the seventh leading cause of time spent disabled worldwide, migraine "has received relatively little attention as a major public health issue," Dr Andrew Charles, a California neurologist, wrote recently in The New England Journal of Medicine. It can begin in childhood, become more common in adolescence and peak in prevalence at ages 35 to 39. It afflicts two to three times more women than men, and one woman in 25 has chronic migraines on more than 15 days a month.
But while the focus has long been on head pain, migraines are not just that. They are a body-wide disorder that recent research has shown results from "an abnormal state of the nervous system involving multiple parts of the brain," said Charles, of the UCLA Goldberg Migraine Program at the David Geffen School of Medicine in Los Angeles. He hoped the journal article would educate practicing physicians, who learn little about migraines in med school.
Before it was possible to study brain function through a functional MRI or PET scan, migraines were thought to be caused by swollen, throbbing blood vessels in the scalp, usually affecting one side of the head. This classic migraine symptom prompted the use of medications that narrow blood vessels, drugs that help only some and are not safe for people with heart disease.
Traditional remedies help only a minority of sufferers. They range from over-the-counter acetaminophen and NSAIDs to prescribed triptans like Imitrex, inappropriately prescribed opioids, and ergots used as a nasal spray. All have side effects that limit how much can be used and how often.
Neurologists who specialise in migraine research and treatment now approach migraine as a brain-based disorder, with symptoms that can start a day or more before the onset of head pain and persist for hours or days after the pain subsides. Based on the new understanding, there are now potent and less disruptive treatments already available or awaiting approval, though cost will certainly limit their usefulness.
To be most effective, the new therapies may require patients to recognise and respond to the warning signs of a migraine in its prodromal phase - when symptoms like yawning, irritability, fatigue, food cravings and sensitivity to light and sound occur a day or two before the headache.
Even with current remedies, people typically wait until they have a full-blown headache to start treatment, which limits its effectiveness, Charles said. His advice: Learn to recognise your early, or prodromal, symptoms signaling the onset of an attack and start treatment right away.
Women - myself included - often develop migraines just before and during their menstrual period. By keeping a headache-and-menstrual-cycle calendar, I discovered I also got a migraine when I ovulated. I recalled that my migraines had been at their worst decades earlier when I was on birth control pills, and realised that estrogen withdrawal triggered them. By then, I was near menopause, but by "filling in" with oral estrogen at the appropriate times, I was could prevent the headaches.
Preventive therapy "should be considered if migraine occurs at least once per week or on four or more days per month," Charles wrote. Possible treatments include beta-blockers; anticonvulsant agents like topirimate and tricyclic antidepressants like imipramine and Botox.
Most exciting, however, are new brain-based remedies that have few if any side effects. They include hand-held or headband devices, like the Single-pulse TMS (for transcranial magnetic stimulation) and the Cefaly t-SNS (for transcutaneous supraorbital neurostimulation), that transmit magnetic or electrical energy to nerves through the skull to the brain.
Nearing federal approval is an exciting new class of drugs that directly target the peptides believed to trigger migraine attacks. They include monoclonal antibodies given by injection or through a vein, and CGRP antagonists taken by mouth.