By Linda Lowenthal, R.N., M.S.N.
Testosterone-Replacement Therapy: For Men Only?
The Sean Connery image: sexy, robust, twinkly-eyed. Quick-witted and fairly well preserved. Most older men wouldn't mind fitting this profile, and the medical community continues to develop ways to make it possible -- from Viagra to testosterone injections. But what about older women? Are they to be consigned to lives marked by weakness and fatigue, declining mental abilities, and a waning sex drive -- or are there better options?
There are indeed, and one of them is based on a biological fact that might surprise you. Testosterone -- the primary hormone in the male body -- plays an important role in the female body too. It affects a woman's sexual functioning, muscle strength, and overall energy levels, among other things. "Testosterone is a normal female hormone produced by the ovary and adrenal gland; in general, that has not been very well known in our society," explains Dr. Michelle McDermott, a board-certified endocrinologist and director of the Menopause Clinic, part of the Austin Diagnostic Clinic in Austin, Texas.
Dr. McDermott is currently involved in trials on testosterone-replacement therapy -- for women. "With the decline of the ovaries after menopause, a woman's testosterone production drops significantly," she explains. Her study and several others show that testosterone may help postmenopausal women retain their vitality -- between the sheets and elsewhere.
Redefining the role of ovaries
Dr. McDermott's current study focuses on older women who have had a hysterectomy that included removal of the ovaries. "These women have the greatest drop in testosterone levels -- they're an easy group to study," she explains. However, she says, "many women, even those who have natural menopause, may benefit from testosterone replacement."
Her comments are supported by a recent study at the University of California-San Diego School of Medicine that examined the histories and current testosterone levels of over 600 postmenopausal women. The results showed that around the time of menopause, testosterone levels dropped sharply in all women, with the strongest drop among those who had undergone a hysterectomy. Furthermore, it was found that in the years following menopause, production of testosterone -- in women who still had their ovaries -- gradually picked up again. In the women whose ovaries had been removed during their hysterectomy, testosterone levels remained at the lower levels.
In other words, the postmenopausal ovary shouldn't be regarded merely as a defunct egg-producing structure, but rather as an important source of testosterone in older women.
A promising treatment
Many postmenopausal women take some form of estrogen -- the primary female hormone -- yet few are currently offered testosterone. "This option just hasn't been discussed with very many of them," notes Dr. McDermott. Yet many women encounter problems that might be best addressed through testosterone therapy when estrogen alone proves inadequate:
Diminished sexual desire. "In my menopause practice, at least 50 percent of my patients express dissatisfaction with sexual function," says Dr. McDermott. Studies have indicated that a combination of testosterone and estrogen can boost sexual desire, the frequencies of fantasies, sexual arousal, orgasms, and overall sexual satisfaction more effectively than estrogen alone.
Fatigue and irritability. Numerous studies have noted an improvement in energy and favorable mood changes in some women after testosterone is added to their hormone therapy.
Bone loss. Both estrogen and testosterone help to prevent osteoporosis, the weakening of the bones that puts so many older women at high risk for fractures. In addition, testosterone seems to stimulate the growth of strong new bone.
Declining intellectual abilities. Older women with higher levels of testosterone tend to do better on verbal fluency tests.
Menopausal symptoms. For women whose hot flashes, night sweats, and mood changes are not adequately managed with estrogen replacement alone, the addition of testosterone can effect considerable improvement.
Testosterone is usually given in the form of pills, monthly injections, or pellets implanted under the skin -- all methods that have drawbacks. Trials are currently underway to test patient-applied skin patches and rub-on gels. Women interested in testosterone therapy should talk to their physician about a convenient method.
Early research noted that increasing the testosterone levels in a woman's body could lead to unfavorable changes in cholesterol (more of the "bad" kind, less of the "good"). Some women also developed acne, facial hair, and coarse voices. Female testosterone treatment therefore gained an unfavorable reputation, a perception that persists among many clinicians as well as the general public.
Most of these early studies, however, focused on women who were receiving well in excess of the necessary amounts of the hormone. Newer research indicates that these side effects usually do not appear when the dosages are adjusted downward.
Another false notion is that testosterone therapy for aging women is something new. Actually, research on the topic has been around since the 1940s. For example, at the McGill University Menopause Clinic, in Montreal, Canada, women who have had a hysterectomy with removal of the ovaries are routinely started on estrogen-testosterone combinations. The women are monitored closely and usually offered continuation of the therapy on an individual basis. More than 1,000 women have done well on this regimen, some for up to 30 years.
Researchers are continuing to study the relative benefits and risks to women interested in taking testosterone. The effects of long-term testosterone replacement, which may continue for decades after menopause, also need to be followed and evaluated.
As research grows, older women will be presented with aging options beyond simply following "nature's course" with grace and resignation. Dr. McDermott concludes that an "increasing awareness of the role of testosterone, as well as additional research, is certain to improve quality of life for postmenopausal women."
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Outside link: Article on testosterone therapy for women from the Journal of the American Medical Association
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