Super-Sensitive Nerves Play Key Role in Migraine Pain
"Not all patients experience increases in skin sensitivity -- and for them existing pain medications are almost 100% effective at any point of the migraine," notes Burstein, vice chair of the anesthesia department at Beth Israel Deaconess Medical Center in Boston. "However, 79% of the patients in our study exhibited this skin sensitivity. These patients will benefit from currently available drugs only if they take them in the first hour after the onset of an attack. If they take them later it is much, much less effective because these drugs do not address the sensitization that develops in the spinal cord."
However, drugs that can prevent or reverse the chemical changes in the spinal cord would benefit these patients. "There are hundreds of ways to do that, and this is the kind of medicine that will eventually do the job," Burstein says. He and his Harvard University research team currently are looking for drugs that can do this without too many unwanted side effects.
Stephen Silberstein, MD, director of the Jefferson Headache Center in Philadelphia, calls the research a major advance in understanding migraines. Silberstein, who was not involved in the study, tells WebMD that the findings confirm something physicians long suspected.
"This is a very important paper because for a long time we have been hypothesizing what happens in people during a migraine attack -- we've been saying maybe it is sensitization, but nobody ever demonstrated it is true," he says. "It tells us why migraine sufferers suffer pain everywhere, why their hair hurts. It may give us better approaches for treatment."
Burstein and his colleagues performed a battery of skin sensitivity tests on patients referred to a pain center for migraines. They then asked the patients to return to the center when they had a migraine so the tests could be repeated.
"The patients all got my pager number and they paged me whenever they got migraines," Burstein remembers. "They would call at three, four, five o'clock in the morning, on Sunday, around the clock. We met them in the clinic four hours into the attack, in which they took no medication. Then all we had to do was subtract the results of the pain testing in the presence of a migraine from the results we got in the absence of the headache. It became obvious that they had changes in their skin sensitivity."