QUESTIONS ABOUT HORMONE REPLACEMENT
© 1997 by Ralph W. Moss, Ph.D.
One of the hottest controversies in medicine concerns hormone replacement therapy (HRT) for menopausal women. For most gynecologists, HRT treatment is a virtual panacea. Frequently, menopausal women are given free samples of the drugs, along with a stern warning on what will happen to them if they do not take such supplements. The benefits are said to be relief of hot flashes, night sweats, vaginal dryness, aging skin, as well as a lower rates of osteoporosis, colon cancer, heart disease, and mental deterioration.
To many doctors, HRT is a virtual religion, one of the really bright spots in contemporary medicine, with its promise of forestalling the scourge of old age. They hold out the promise of prolonged youthfulness and sexiness to middle-aged women, and insist that they start taking HRT at the onset of menopause and continue with it for the rest of their lives. Is it any wonder that these are among the most profitable drugs in history?
In America, the drug of choice is Prempro, manufactured by Wyeth-Ayerst's Ayerst Laboratories, Inc. Each peach-colored Prempro tablet contains 0.625 mg of conjugated estrogens and 2.5 mg of another synthetic hormone, medroxyprogesterone acetate (MPA). The progesterone-like hormone is added because of the cancer-risk of unalloyed estrogen. One tablet is usually taken daily.
Holistically oriented doctors have generally been skeptical of the product, believing that it is not safe. Many feel that similar benefits can be derived from more natural agents. Soy products, for instance, seem able to relieve most menopausal symptoms. Dr. Margaret Lock did a study of the menopause in different countries. She points out that there are no words for "hot flashes" in Japanese (Lock, M., et al. Maturitas 1988;10:317-332). The Japanese diet, with high intake of soy, seems to relieve any such symptoms. The same seems to be true in China.
DANGERS OF MPA?
Now a study at the Oregon Regional Primate Research Center in Beaverton, OR raises questions about the safety and efficacy of Prempro-type products. A team, led by Kent Hermsmeyer, removed the ovaries from 30 rhesus monkeys, to simulate menopause. They then gave estrogen supplements daily to 18 of these monkeys. Six also got natural progesterone, while 6 more also received the synthetic MPA.
After 4 weeks, the researchers injected all the animals with chemicals that are released by blood platelets. This injection simulated a heart attack. The monkeys that received just estrogen or that received estrogen plus the natural progesterone all recovered normal blood flow, without drug treatment. However, those animals that were treated with the Prempro-like product suffered an unrelenting constriction of their coronary artery, cutting off the blood flow. Unless they were treated within minutes, they would have died, said Dr. Hermsmeyer. This was the same outcome as animals that received no hormone therapy at all.
The results were printed in the March 1997 issue of Nature Medicine and the March 1, 1997 issue of the Journal of the American College of Cardiology.
J. Koudy Williams of Wake Forest University's Bowman Gray School of Medicine concurs. His own experiments show that MPA can "obliterate the beneficial effects of estrogen [therapy] on the progression of coronary artery atherosclerosis."
In London, England, Peter Collins of the National Heart and Lung Institute reproduced some of these effects in women with coronary artery disease. First he put then on two hormone replacement therapies for several weeks. One group received estrogen plus natural progesterone. The other received estrogen plus MPA. Then Dr. Collins had the women exercise on a treadmill until they experienced reduced blood flow to the heart. The women who were receiving the natural product could exercise longer than those who were receiving the MPA-containing drug.
As far as MPA is concerned, Dr. Collins told Science News, "there's enough data accumulated to give us pause." In terms of heart disease protection, "it's worse than no treatment at all."