Migraines linked to brain lesions and increased risk of stroke in
women
by Drucilla DYESS
Migraine headaches affect approximately 17 percent of the
populationat sometime during their life, accounting for more than 1
billionpeople who suffer from the condition worldwide.
 American
and Europeanstudies have shown that 6-8 percent of men and 15-18 percent
of womenexperience migraine every year. The significantly higher rates
among women are hormonally driven. According to a new report published
in the Journal of the American Medical Association, women who experience
migraines accompanied by avisual disturbance known as an aura, have an
increased risk ofsustaining long-term microscopic damage to brain tissue
that isimportant to both coordination and the senses. In addition, a
secondstudy appearing in the journal Neurology revealed that women
whoexperience frequent migraines along with an aura, have a four
timesgreater likelihood of suffering a stroke in later years than
womenwithout migraines.
The finding supports previous studies that suggest an association
between migraines and stroke.A migraine headache is most commonly
experienced as a throbbing painthat is felt only on one side of the
head. These headaches are causedby abnormal brain activity that may be
triggered by stress, certain foods, environmental factors, or other
factors. The exact chain of events that set off migraines remains
unknown. Symptoms accompanying the head pain may include nausea,
vomiting and sensitivity to light. Although scientists once believed
that migraines were caused by changes in blood vessels within the brain,
most medical experts now believe the condition begins in the brain
itself and involves various nerve pathways and chemicals.
The changes affect blood flow in the brain and surrounding
tissues.Some migraine sufferers experience attacks accompanied by an
aura thatcauses vision disturbances such as arcs of sparkling light,
zigzaglines, blurry spots or loss of vision.In the first study, Lenore
Launer, a neuroepidemiologist at theNational Institute on Aging,
analyzed a registry of data on over 4,000people in Iceland in which
their health has been followed since 1967.Magnetic resonance imaging (MRI)
was performed on the Icelandic people25 years after the registry began
to document evidence of tiny brainlesions.
The researchers found that 23 percent of women having history of
migraines with aura had suffered microscopic brain damage, whereas only
15 percent of women with no history of migraines had evidence of the
brain lesions.
This led to the determination that the women in themigraine-with-aura
group were 1.5 times more likely to develop lesionsthan other women in
the registry.Launer acknowledged that the findings offer no proof of
migraine withaura directly causing brain damage, nor do they determine
what the risks of having the lesions might be. She says, "These look
like verytiny strokes, but we don't know what the functional
consequences of these lesions are." However, she noted that if a link
betweenmigraines and lesions is shown, the finding could disprove past
theories that migraines are short-lived headaches that have no
lastingeffects. Tobias Kurth, a neurologist and epidemiologist at INSERM,
the French national health and medical research agency in Paris, France
and colleagues, conducted the second study.
This group of researchersanalyzed data on over 27,000 U.S. women,
including more than 2,500 who suffered from migraines, and a total of
1,095 who also experienced auras. During the 12 years of the study,
those who had a history of experiencing auras once a week or more were
discovered to be fourtimes as likely to suffer a stroke than women who
had no migraines. Kurth pointed out that although the incidence of
stroke in women withmigraines with aura in the study was higher than
that of women who had no migraines, it was still very low at a risk of
only 3 percent.
He also noted that the study does not reveal whether migraines are
causally connected to strokes or vascular damage by any known biological
mechanism
- Health News
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