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Hormone Therapy: The Answers Are In

Few things are more upsetting than having to revise your beliefs, especially when your own physician may have encouraged those beliefs, and an array of experts cited scientific evidence to back them up. In July the Women's Health Initiative, the best study so far of hormone replacement therapy (HRT) in healthy women, showed that the treatment actually increases the risks of heart disease and breast cancer, outweighing any protection against fractures and colon cancer. True, the study showed that if taken for less than four or five years, hormone therapy is a reasonably safe way to deal with menopausal symptoms. But this is a far more modest benefit, overall, than most women had been led to expect.

Now women are asking, "What should I do?" and "Have I done myself real damage in taking this stuff?" The answer to the first question is complicated; the answer to the second is probably no.

How we got here

About two out of five postmenopausal American women are on hormones, or were until last summer—a trend that began its upward trajectory some 30 years ago. Hormone therapy comes in two types: estrogen alone (ERT) or the combination of estrogen and progestin, known as HRT. The idea that taking estrogen after menopause helps protect women against osteoporosis has been well established. And there's logic to the idea that it should also protect against cardiovascular disease. Numerous studies have found benefits. And hormone therapy can counteract unpleasant (and occasionally unbearable) menopausal symptoms, such as hot flashes, vaginal dryness, night sweats, and mood swings.

There are many other reasons why hormone therapy has been so popular—optimism being only one of them. There were claims (totally unfounded) that it would keep a woman "forever feminine" and "forever young." The companies that made the hormones helped promote such notions, and journalists quickly joined the parade. Understandably, women want to stay healthy into old age, especially now that it's reasonable to expect to live 30 or more years past menopause. Doctors were (and are) eager for medications that will help.

All along, however, there were questions. ERT was shown to promote cancer of the uterus, but it turned out that this effect could be countered by adding progestin to the pill—hence HRT. (Estrogen by itself was reserved only for women who had had hysterectomies.) Whether HRT raised the risk of breast cancer was another troubling problem. Many doctors were reluctant to prescribe HRT for women at high risk for breast cancer. But as a way to reduce the risk of cardiovascular disease and bone loss, ERT and HRT continued to look promising.

Yet, until now, one thing was always missing: a large-scale, well-designed clinical trial that tested the safety and effectiveness of hormone therapy as a way to prevent disease in healthy women. No matter how carefully conducted, all the studies had been observational. That is, they followed groups of women taking hormones and recorded outcomes—a valuable kind of research, but never definitive. For example, women who took HRT tended to lead healthier lives, and maybe this, rather than HRT, is what benefited their hearts. At last, the National Institutes of Health began the needed clinical trial, called the Women's Health Initiative. In part of this study, women were randomly assigned to take HRT (Prempro, the most popular form) or a placebo. The trial was to have lasted eight and a half years, but was terminated after a little more than five years to protect the participants from further risk, specifically the rising risk of breast cancer.

What the study found

The news is not as terrible as some reports have claimed. At least we know some things for sure now. Women and their doctors have long known or strongly suspected that hormone therapy increases the risk of breast cancer. What's new is the increased risk of cardiovascular disease—though in recent years there had been studies suggesting that this would turn out to be the case.

Here are the main findings:

• During the five years, women on HRT had slightly more heart attacks, stroke, and blood clots. But the increase in risk was very small. And there were no extra deaths.

• HRT taken for more than four years slightly increased the risk of breast cancer.

• Though HRT helped prevent fractures, the effect was small and would last only as long as you take the hormones.

• Women on HRT had a slightly lower incidence of colon cancer.

What to do

• If you are a healthy postmenopausal woman who is taking HRT solely to prevent chronic disease, it makes sense to stop. But talk with your doctor. You may need advice about whether to quit abruptly or to taper off. Get professional advice about ways to stay healthy without HRT. A healthy diet, regular exercise, and refraining from smoking are of major importance. See Wellness Letter, July 2000, for advice on lowering your risk for cardiovascular disease, and April 2001 for information about how to maintain strong bones.

• If a bone-density test shows that you need a drug to ward off osteoporosis, bisphosphonates such as Fosamax and Actonel are good alternatives. Other options include raloxifene (Evista) and calcitonin (a hormonal nasal spray). Remember, though, that the long-term safety of bisphosphonates, raloxifene, and calcitonin has not yet been determined.

• A colonoscopy and other tests can prevent or cure colon cancer by detecting polyps early.

• An annual mammogram remains the most reliable way to detect breast cancer in time to cure it.

• If you are treating severe menopausal symptoms with HRT, that's fine, at least for less than four or five years. But take it only as long as is necessary. As with any drug therapy, you'll need to check with your doctor and re-evaluate at regular intervals.

• Turning away from HRT, many women are likely to try untested alternative treatments, such as soy supplements, isoflavones, black cohosh, oil of evening primrose, and flaxseed oil, especially for menopausal symptoms. Remember that far less is known about such supplements than about hormones. If HRT is risky, plant hormones may be risky, too. Studies of black cohosh have so far shown no benefits. Beware of jumping on another bandwagon. (We'll discuss these and other alternatives in an upcoming issue.)

• If vaginal dryness is your chief menopausal symptom, there are good nonhormonal, nonprescription lubricants such as Replens and Astroglide, as well as estrogen creams, which are only minimally absorbed into your body.

• If you have had a hysterectomy and are taking ERT, there's no evidence indicating that you should stop. The Women's Health Initiative is continuing to investigate ERT, but so far has not produced any alarming evidence. If you have concerns, it's a good idea to discuss them with your physician.