“We feel your pain.” More than half of neurologists, and three-quarters of headache specialists, can say that quite literally to their patients who suffer from migraine, according to a new study in Neurology (2003;61:1271–1272).
While noting that the lifetime prevalence of migraines in the US has been pegged at 25 percent for women and 8 percent for men, the study of 220 neurologists found a lifetime prevalence of 62.8 percent for female neurologists and 46.6 percent for male neurologists. Among headache specialists, the lifetime prevalence stood at 81.5 percent for women and 71.9 percent for men.
One-year prevalence of migraine in the general population has been reported at 18 percent for women and 6 percent for men. By contrast, the new survey found the one-year prevalence for neurologists to be 58.1 percent for women and 34.7 percent for men. Among headache specialists, the one-year prevalence was 74.1 percent for women and 59 percent for men.
While confirming the long-held suspicions of many, the survey of neurologists nonetheless evoked a great deal of puzzlement. “It's a great study, which has attracted a lot of attention,” said Sheena Aurora, MD, a neurologist and headache specialist at Swedish Hospital in Seattle, WA. “We just don't know what to make of it.”
IS IT A PLACEBO EFFECT?
“Maybe there is a ‘tip of the iceberg’ effect where neurologists correctly identify migraine of a mild or idiosyncratic nature that would not have been diagnosed or ascertained in the general population,” speculated neuroepidemiologist Lorene Nelson, PhD, Associate Professor of Health Research and Policy at Stanford University.
The lead author of the study, Randolph W. Evans, MD, Chief of Neurology at Park Plaza Hospital in Houston, TX, said he could offer no definite explanation for the findings. “The published study reviews several possible explanations, discarding some, favoring others.”
The most obvious theory – sampling bias – seemed unlikely, the researchers concluded, due to their methodology. Rather than using the conventional approach of mailing or faxing the survey, Dr. Evans and his co-authors administered theirs in person at nine regional continuing education courses on headaches offered by the Neurology Ambassador Program, a program jointly sponsored by the AAN and the American Headache Society; 79.5 percent of attendees completed the survey.
COMPARING WITH NON-NEUROLOGISTS
In addition, to check for the possibility of selection bias – that those interested in headaches would be more likely to suffer migraine – the researchers also handed out a short form of the survey to the neurologists attending a neurology meeting in Texas having nothing to do with headaches, and found migraine prevalence rates nearly identical to those seen in the Neurology Ambassador Program sample.
“It is well designed given the types of study populations available to them to do a study like this,” commented Dr. Nelson. “The fact that they found amazingly similar findings between the two groups makes it seem more credible. They are a careful group of investigators.”
Co-author Stephen D. Silberstein, MD, is Professor of Neurology and Director of the Jefferson Headache Clinic at Thomas Jefferson University School of Medicine in Philadelphia, PA, and co-author Richard B. Lipton, MD, is Professor in the Departments of Neurology, Epidemiology, and Population Health at Albert Einstein College of Medicine in the Bronx, NY.
The study authors speculated that neurologists are simply better than the general population at self-diagnosing their own migraines. If this were the case, the prevalence estimates for migraine seen in the general community might be artificially low.
Alan Leviton, MD, a neuroepidemiologist at Harvard Medical School, agrees. “My colleagues tend to accept the axiom that the more experienced the clinician, the more likely she or he is to consider that migraine is under-diagnosed among people with recurring headaches,” he said.
The problem with that theory, however, is that “because all neurologists should be able to recognize their own migraines, this would not account for the higher rate of migraine among headache specialists vs neurologists,” the study noted.
A HISTORY OF MIGRAINE
Most of the experts interviewed here believe that neurologists in general, and headache specialists in particular, self-select the field because of a prior personal history. “I have been known to tell residents that they cannot be neurologists unless they have migraine,” Dr. Leviton quipped.
Such was the case for the well-known author and neurologist Oliver Sacks, MD, who wrote a letter in response to the study in the January 27th Neurology (2004;62:342). “For myself,” Dr. Sacks wrote, “with a personal history of classical migraines (and, more often, isolated visual ones) going back to childhood, the extraordinary phenomena of the aura (which for me included transient or partial achromatopsia, akinetopsia, as well as visual agnosias, alexias, etc), excited an interest in the brain, and especially in visual processing, at an early age. These migraines were certainly one of the reasons I was attracted to neurology, why I chose migraine as the subject of my first book, and why I devoted a large part of this book to illustrating the varied presentations of visual auras in my patients.”
A personal history of migraine also brought Dr. Evans into the field. “I've had them at least since I was a teenager,” he said. “Over the years I've had some really severe migraines. When I was a resident, I'd get one after being up all night on call. It probably subconsciously played a role in my interest in headaches.”
But a problem with the self-selection theory is that respondents whose migraine began before starting neurology residency were asked the following: “Was your personal history of migraine a significant factor in deciding upon your specialty?” At the Neurology Ambassador Programs, most reported that there was no effect at all: female neurologists, 91.3 percent; male neurologists, 92 percent; female headache specialists, 81 percent; male headache specialists, 76.5 percent.
Dr. Nelson took those answers with a grain of salt. “I'm not sure that self-selection isn't a possible explanation,” she said. “Scientists and physicians want to appear to be as objective as possible. Some may have had it as an unconscious reason. Certainly to me it seems perfectly understandable that if you have a condition that you might be more interested in learning more about it.”
Whatever the cause, Dr. Evans and others expressed no doubt that the findings were accurate. “I don't think you'll get any arguments that the study is a fairly accurate picture of neurologists and migraines,” he said. “If you just ask for a show of hands at a meeting, about half of neurologists will raise their hands.”
Dr. Aurora said she had a similar experience when she has given lectures on headaches to an audience of neurologists.
Much as they may feel migraine sufferers' pain, however, neurologists might nevertheless feel less sympathy than one might expect for those patients who moan and groan too much about it, Dr. Evans said.
“Sometimes I'm less sympathetic because the patient is going on and on, complaining about how terribly they feel about having a migraine once a month, and I'm sitting there having a terrible migraine myself,” he said. “I think it's true of doctors in general that they're more stoic and likely to persevere. Our study found that neurologists rarely, if ever, miss work due to migraine.”
ARTICLE IN BRIEF
- ✓ A study in the January 27th issue of Neurology reported that migraine is highly prevalent among neurologists and headache specialists.
- ✓ Several neuroepidemiologists and other experts commented that a personal history of migraine might prompt neurologists to pursue the specialty.