|
Estrogen
Does Not
Prevent Recurrent Strokes
Excerpt
By
Amy Norton, Reuters Health
NEW YORK (Reuters Health)
- Despite some past evidence that hormone replacement might lower
stroke risk in older women, new research shows that estrogen therapy
does not protect women from recurrent strokes and may instead
carry some risks.
The findings add to growing evidence that hormone replacement
therapy does not have the cardiovascular benefits doctors once
believed.
In a study of 664 postmenopausal women who had recently suffered
strokes, researchers found that estrogen replacement therapy (ERT)
did not reduce their rate of further strokes. What's more, when
they did suffer strokes, women on ERT were slightly more likely
than non-users to die or have neurological damage.
These findings show that older women should not go on ERT solely
for the prevention of recurrent strokes, according to Dr. Catherine
M. Viscoli and colleagues at the Yale University School of Medicine
in New Haven, Connecticut. Their report is published in the October
25th issue of The New England Journal of Medicine.
The women in the study had all suffered strokes within the previous
3 months. As for women with more ``remote strokes'' who are already
on hormones, they ``would probably be wise to have a careful discussion
with their doctors'' about whether to stay on the therapy, Dr.
Walter N. Kernan, a co-author on the study, told Reuters Health.
Many doctors have long thought hormone replacement therapy might
help protect women's cardiovascular health, warding off heart
disease and, possibly, stroke. But recent research has questioned
that reasoning.
In July, the American Heart Association issued guidelines stating
that women should not receive hormone replacement for the sole
purpose of preventing recurrent heart attacks. This came after
several studies suggested the combination therapy of estrogen
and progestin actually raises the risk of recurrent heart attack,
at least temporarily.
The fact that the proposed cardiovascular benefits of hormone
replacement have not panned out in recent studies is ''really
surprising,'' Viscoli said in an interview.
There have been some strong reasons to believe in the idea, including
studies showing hormone users had lower rates of death from cardiovascular
causes and the fact that hormone replacement can improve women's
cholesterol levels.
But the current evidence on hormones and stroke risk looks negative,
according to Viscoli. She noted that a large, ongoing trial called
the Women's Health Initiative is looking at whether hormone replacement
can help prevent the onset of cardiovascular disease. But so far,
the early results have shown a slightly increased risk of strokes
and heart attacks.
Currently, the only well-established benefits of hormone replacement
are in reducing menopause symptoms, such as hot flashes, and in
preserving bone mass.
In the current study, Viscoli and her colleagues followed women
who had had either an ischemic stroke or a ``mini-stroke'' known
as a transient ischemic attack. An ischemic stroke occurs when
blood flow to the brain is obstructed, and is the most common
type of stroke.
Some of the women took a daily dose of oral estrogen, while the
rest took an inactive placebo. After an average of nearly 3 years,
the researchers found no difference in the risk of nonfatal stroke
between the two groups.
Only a small number of women suffered fatal strokes, but there
were 12 deaths in the ERT group, compared with 4 in the placebo
group. Women on estrogen were also slightly more likely to show
neurological impairment after suffering a stroke.
The researchers conclude that the results ``add to the evolving
body of evidence from clinical trials that do not show a benefit
of estrogen for women with established vascular disease.''
SOURCE: The New England Journal of Medicine 2001;345:1243-1249.
Reference
Source 89
For more information on how to prevent other diseases, use
PreventDisease.com's "Quick
Prevention Resources".
|