- OTTAWA -- Migraines can kill
people's brain tissue and leave permanent physical changes there, say Dutch
and American doctors who want the overpowering headaches redefined as a
progressive brain disease.
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- The discovery that people with migraines have more of
these dead or altered areas than migraine-free people has surprised the
researchers, who thought the headaches left no scars.
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- "It changes the common perception that migraines
are trivial problems with transient symptoms," says Dr. Lenore Launer,
a lead author of the study and neurologist at the U.S. National Institute
on Aging. "Right now people feel there's an attack, and you endure
it or treat it, and then it's over."
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- Now she says migraines must be re-defined as a chronic
problem that can leave lasting effects beyond pain.
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- The migraines cause two kinds of damage, though only
in a minority of sufferers -- a little more than 10 per cent.
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- In some people they cause infarctions -- areas where
a small blood clot blocks a blood vessel, killing the brain tissue around
it.
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- The other brain changes are more of a mystery, an effect
known for years as an "unidentified bright object" among people
who did MRI scans of the brain, because it shows up on the scan as a bright
area. It's now called a white matter lesion.
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- "It's something not normal," Launer says, but
it's tough to define. It's an effect covering a spread-out area, not a
clearly defined point. It's probably caused by a lack of nutrients to cells
in that area of the brain, or perhaps by inflammation, or even edema --
a buildup of fluid.
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- "In fact these are not innocuous," she adds.
"They're thought in older people to make them subject to cognitive
impairment, and also to some physical impairment -- walking speed, for
instance. People with these may not be able to walk as fast."
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- Women who suffered migraines once a month or more were
2 1/2 times more likely to have these lesions than women without migraines.
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- The other kind of damage is an "infarction,"
where a small area of the brain dies after its blood supply is cut off,
usually by a clot in a blood vessel.
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- There were 60 such dead areas found in 31 of the patients,
mainly migraine sufferers, Launer said. They ranged in size from two millimetres
wide to a little more than two centimetres. This damage was seven times
more common in people with migraines than in other people, and 13 times
more common among those with "aura" migraines, those that include
visual disturbances.
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- However, a series of psychological tests found the people
with these dead brain areas didn't appear to suffer any loss of ability
to think or move their bodies. She hopes to examine that question more
deeply.
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- Both effects happen more often in women, the researchers
say, and especially in women who suffer from "aura" migraines.
As well, the damage was most common in people who have migraines at least
once a month.
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- The damage showed up in MRI scans of the brains of 435
Dutch men and women aged 30 to 60. About two-thirds of the group suffered
from migraines while the rest, who never had migraines, were studied for
comparison.
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- While there's no new treatment available as a result
of this study, Launer says future doctors may change the way they treat
migraine sufferers because they know of the long-term physical damage.
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- © The Vancouver Sun 2004
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- http://www.canada.com/vancouver/vancouversun/news/story.htm
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