by Playfuls Staff |
19th December 2006
The results of a federally funded study to examine whether
black cohosh is an effective treatment for hot flashes and night sweats -
common symptoms of menopause - found that black cohosh was no better than [more]
a dummy pill.
The frequency and severity of symptoms declined by about
30 percent over 12 months regardless of whether women were taking black cohosh
or placebo.
Black cohosh, a perennial herb member of the buttercup
family, is the most widely used herbal remedy for hot flashes.
The Herbal Alternatives for Menopause Trial (HALT), was a
one-year, double-blind, randomized, controlled trial comparing the effects of
three formulations of black cohosh with hormone therapy and placebo for relief
of hot flashes and night sweats.
Researchers assigned 351 women aged 45 to 55 to one of
five groups:
* black cohosh
alone
* multi-herb
pill with black cohosh and nine other ingredients
* the multi-herb
pill plus counseling to increase intake of dietary soy
* hormone
therapy (estrogen with or without progestin)
* placebo (dummy
pill)
"About 80 percent of women who go through menopause
experience hot flashes," said Katherine M. Newton, PhD, Associate Director
for Research at Group Health in Seattle, and lead author of the study.
"Many women are looking for alternatives to hormone
therapy which is the most proven remedy for hot flashes, and many are using
alternative medicines," Newton
said. "The most commonly used alternative is black cohosh. But we found
that black cohosh was no better than placebo in treating hot flashes."
The study found that hormone therapy gave women most
relief, reducing symptoms by an average of about four symptoms per day more
than placebo.
Hormone therapy was included in the HALT study because it
is a well-known and proven treatment to reduce menopausal symptoms. The HALT
study began in 2001 and stopped the hormone therapy arm of the trial after the
Women's Health Initiative found in 2002 that estrogen plus progestin increased
risk for breast cancer, heart attacks, strokes and blood clots.
"Whether or not the black cohosh findings are bad
news for women depends on how you look at it," said Newton. "It's disappointing that we
didn't find black cohosh to be an effective remedy.
On the other hand, thousands of women, probably hundreds
of thousands of women, buy products that contain black cohosh to help relieve
their menopausal symptoms. Our study indicates that black cohosh is not a
promising remedy to treat their hot flashes."
The HALT study was funded by the National Institute on
Aging and the National
Center for Complementary
and Alternative Medicine. It is the most definitive study yet of the effects of
black cohosh. Previous studies have been small, short-term studies that were
inconclusive.
The study, "Treatment of Vasomotor Symptoms of
Menopause with Black Cohosh, Multibotanicals, Soy, Hormone Therapy, or
Placebo," and an accompanying editorial, " A Randomized Trial of
Alternative Medicines for Vasomotor Symptoms of Menopause," is published
in the Dec. 19, 2006, issue of Annals of Internal Medicine.
Editorial writers say the study is a "well-designed,
adequately powered RCT that makes an important contribution, albeit one that
will disappoint women who have been hoping for an effective, safe alternative
to estrogen."
The good news, the editorial writers say, is that women in
the placebo group experienced about a 30 percent reduction in severity and
frequency of symptoms during the 12-month follow-up period.
This means that many women will probably have fewer
symptoms within six to 12 months without any treatment at all.
