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18 February 2003 | Volume 138 Issue 4 | Pages 361-364
On 23 and 24 October 2002, the National Institutes of Health (NIH) convened a Scientific Workshop on Menopausal Hormone Therapy. Dr. Ruth Kirschstein, Deputy Director, NIH, and Dr. Vivian Pinn, Director of the Office of Research on Women's Health, NIH, opened the conference, stating that the purposes of this scientific workshop were to place the WHI E + P clinical trial results and reasons for stopping the trial in the context of other federally funded studies (such as those evaluating the effect of HT on cognition and osteoporosis) and to help clinicians and their patients better understand the current information on the risks and benefits of short- and long-term use of combination HT.
The results from other combination HT trials were considered by the DSMBs of all NIH-funded clinical trials involving HT. Some of these studies were discontinued, and others were recommended for continuation. To provide the conference attendees with the necessary background about decision making in protecting participants in clinical trials, Dr. Diana Petitti of Kaiser Permanente in Southern California reviewed the purpose of a clinical trial and how DSMBs evaluate risks and benefits for study participants. CURRENT CLINICAL ISSUES
Menopausal Hormone Therapy: Summary of a Scientific Workshop
Although the primary reason for hormone therapy (HT) is to relieve the vasomotor symptoms of menopause, several observational studies have suggested that long-term HT protects against coronary heart disease and osteoporotic fractures. Thus, in the early 1990s, the National Institutes of Health implemented a large prevention study, the Women's Health Initiative (WHI), to determine whether long-term HT could prevent coronary heart disease (CHD) in postmenopausal women and to assess the overall benefits and risks of long-term HT. In studies of women 50 to 79 years of age, those who still had a uterus were randomly assigned to receive daily combination HT (0.625 mg of conjugated equine estrogen plus 2.5 mg of medroxyprogesterone [E + P] as Prempro, from Wyeth-Ayerst) or placebo; those who had had a hysterectomy received estrogen alone ([E-alone] as Premarin, also from Wyeth-Ayerst) or placebo. The combination HT trial was stopped in July 2002 after 5.2 years because the risks of E + P (increases in breast cancer, coronary heart disease, stroke, and pulmonary embolism) were considered to outweigh the benefits (reduction in hip fracture and colorectal cancer). The companion E-alone trial continues, with close monitoring by the data and safety monitoring board (DSMB). Participants in the E-alone trial were informed that risk for breast cancer had not increased at 5.2 years. Like participants in the E + P trial, participants receiving only E had been notified in 2000 and 2001 of increased risks for heart attack, stroke, and blood clots during the early years of the trial.
WHI: Results, Other Trials, and Ancillary Studies
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Dr. Marcia Stefanick, WHI Steering Committee Chair from Stanford University, summarized the cardiovascular studies that led to the WHI trials. These included the Postmenopausal Estrogen/Progestin Interventions (PEPI) trial, which compared the effects of E alone, and E plus many progestin regimens, on CHD risk factors (
The Writing Group for the PEPI TrialEffects of estrogen or estrogen/progestin regimens on heart disease risk factors in postmenopausal women. JAMA. 1995;273:199-208.
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The National Heart, Lung, and Blood Institute (NHLBI) has sponsored other studies to elucidate the effects of HT on cardiovascular disease, according to Dr. David Gordon from the NHLBI. For example, the Estrogen Replacement in Atherosclerosis (ERA) trial, involving 309 postmenopausal women with coronary artery disease, was published 2 years ago; the study showed no statistically significant differences in angiographic end points for women who received E + P, E-alone, or placebo (
Herrington DM, Reboussin DM, Brosnihan KB, Sharp PC, Shumaker SA, Snyder TE. Effects of estrogen replacement on the progression of coronary-artery atherosclerosis. N Engl J Med. 2000;343:522-9.
The National Institute of Child Health and Human Development (NICHD) supported the Women's Contraceptive and Reproductive Experiences Study, a cancer casecontrol study conducted in five U.S. metropolitan areas for women 35 to 64 years of age. According to Dr. Robert Spirtas of NICHD, one part of this retrospective study examined the association between breast cancer risk and use of postmenopausal HT. Continuous combined HT was associated with increased risk for breast cancer among women who had been using HT for 5 years or longer. For former users of HT, breast cancer risk did not increase. Estrogen-alone therapy was not associated with increased risk for breast cancer at any disease stage, regardless of the duration or recency of use (Obstet Gynecol. [In press]).
Dr. Joan McGowan of the National Institute of Arthritis and Musculoskeletal and Skin Diseases described two studies on alternative therapies for osteoporosis. One trial to determine whether HT exacerbates disease symptoms in women with systemic lupus erythematosus was discontinued at the recommendation of the DSMB. A second, measuring bone mineral density, was continued because it is using a low-dose regimen of combination HT. Alternative strategies for preventing and treating osteoporosis are available, and more are being studied.
The National Institute on Aging (NIA) is supporting research to study estrogen effects on cognition. According to Dr. Judith A. Salerno from the NIA, that research is based on epidemiologic and small clinical studies that indicate a decreased risk for Alzheimer disease and cognition deficits in women who used estrogen therapy. However, this finding has not been consistent; some clinical studies had serious methodologic limitations, and some biological studies pointed to mechanisms for a protective effect. Of 24 treatment studies conducted from 1976 to 2001, 6 showed positive effects, 11 were equivocal, and 7 showed no effect. One NIA clinical trial is investigating the relation between memory and use of an estradiol patch and the patch plus oral medroxyprogesterone, while another is studying the use of Premarin and Prempro in normal women who have a first-degree relative with cognitive disease. The respective DSMBs recommended that both studies be continued, with notification and re-consent of enrolled research participants.
Two ancillary studies within the WHI are studying the effects of hormones on cognitive impairment, according to Dr. Sally Shumaker of Wake Forest University. The WHI Memory Study examines all phases of dementia in women age 65 years and older. The WHI Study of Cognitive Aging (WHISCA) is assessing whether HT protects against age-associated memory and cognitive decline in women older than 65 years. The E + P arms of both studies were discontinued in June 2002, and results from these studies will be published in early 2003.
Assessing and Communicating Risks and Benefits
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Women who are most likely to benefit from combination HT are those at high risk for hip fracture, those who have previously had a vertebral fracture, or those at high risk for colon cancer. However, according to Dr. Grady, many of those women, including those with osteoporosis, will receive no net benefit from combination HT when the harms and benefits are calculated.
Although the WHI focused on prevention, not on symptom relief and other quality-of-life benefits, many members of the news media and the public did not understand that subtlety, according to Susan Dentzer from The NewsHour with Jim Lehrer on PBS. Although news stories were written in the context of prevention, the public was interested in stories related to quality of life and symptom relief. Neither the news organizations nor the public grasped the concepts of absolute risk and relative risk, and there was a tendency to focus mostly on sharp increases in relative risks, which were emphasized in press releases from the NIH and JAMA. Hence, the media emphasized one "side" of the story or the othereither the sharply increased relative risks or the lesser absolute risks. The differences between these two concepts are significant: Although the relative risk for breast cancer among women in the WHI study who used E + P increased 26% during the 5 years of the study, the absolute risk in an individual woman was small.
What women are really worrying about is disease risk versus the benefits of symptom relief and quality of life, according to Ms. Dentzer. Women also want more timely information about doses, drugs, supplements, and other therapies. This information is especially urgent since no other available therapeutic options are as effective in symptom relief as combination HT.
Future announcements of this type should be accompanied by more concerted efforts to brief the news media thoroughly, Ms. Dentzer recommended. Moreover, thoroughly briefing medical professional groups and clinicians before a major announcement would help them to provide more useful and timely information to their patients.
Food and Drug Administration Perspective
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Food and Drug Administration approvals of hormone products for treating menopausal symptoms are usually based on 3-month, placebo-controlled trials involving approximately 100 participants, with end points of clinical improvement of vasomotor or genitourinary tract symptoms. Approval for osteoporosis prevention is based on bone mineral density measurements in 2-year trials involving approximately 300 participants. Whereas several other types of products are approved by the FDA for increasing bone mass and preventing osteoporosis, no other FDA-approved products are available for treating menopausal symptoms.
Although the WHI risk findings regarding the E + P trial provide important information, it is not possible to extrapolate those findings and apply them to other doses and toxicities of related products, according to Dr. Woodcock. In the case of clinical trials evaluating preventive indications of products, such as the WHI's E + P trial, investigators carry a higher burden to prove a positive benefitrisk ratio. In this case, for example, it might be possible to improve that ratio by administering E + P to women with more recalcitrant menopausal symptoms or to women considered at especially high risk for osteoporosis. Meanwhile, the FDA believes that alternative hormonal treatments involving different doses and routes of administration are worth examining. The risks to users of such products can be communicated through product labels, patient education, and responsible advertising.
An Industry Perspective
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Therapeutic decisions on the use of HT should be individualized. The WHI data have helped to quantify selected risks, including coronary heart disease, venous thromboembolic disease, stroke, and breast and endometrial cancer. The quantifiable absolute risk for these events was low and would be expected to be even lower in a younger, newly menopausal population. Combination HT should be used for the shortest duration that is consistent with treatment goals and risks to the individual woman. Treatment should be re-evaluated periodically; these re-evaluations are especially important when longer therapy (particularly >5 years) is being considered.
Current Considerations for Use of Combination HT
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Treating Vasomotor Symptoms of Menopause
The ACOG and the North American Menopause Society both recommend that taking combination HT to manage vasomotor symptoms should be limited to the shortest duration consistent with treatment goals and benefits versus risks for individual women, taking into account issues of quality of life. Alternative delivery methods such as vaginal creams, vaginal tablets, or a vaginal ring can be effective and do not appreciably increase systemic estrogen levels. However, there are few data to assess the long-term benefitrisk ratios of these alternatives. The North American Menopause Society noted that WHI data cannot be extrapolated directly to symptomatic perimenopausal women or to women experiencing early menopause (40 to 50 years of age) or premature menopause (age < 40 years).
According to Dr. Lorraine Anne Fitzpatrick from the Mayo Clinic and Foundation, the following substances do not work very well, if at all, for treating vasomotor symptoms such as hot flashes: vitamin E, evening primrose, soy isoflavones, dong quai, red clover, naloxone, propranolol, ginseng, yam cream, and Chinese medicinal herbs. Clonidine and methyldopa can reduce the frequency of hot flashes but cause dizziness and dry mouth. Of the antidepressants, venlafaxine is the best studied and has demonstrated efficacy. Other agents being considered but not yet well studied include selective estrogen receptor modulators, selective serotonin reuptake inhibitors, mirtazapine, gabapentin, black cohosh, and chasteberry.
Other modalities for patients and their health care providers to investigate include meditation, acupuncture, hypnosis, biofeedback, and deep breathing exercises. Dr. Fitzpatrick advised women to keep a diary to assess hot-flash triggers; increase exercise; stop smoking; avoid spicy food, caffeine, and alcohol; wear layered clothing; and maintain a low ambient temperature when possible.
Long-Term Use of Combination HT
The participants at the meeting agreed that combination HT has no role in the prevention of cardiovascular disease. Women who are taking combination HT for this purpose should discontinue using the drug. As noted in the presentation of the recommendations from the U.S. Preventive Services Task Force, evidence is insufficient to recommend for or against the use of unopposed estrogen for prevention of chronic conditions in postmenopausal women who have undergone a hysterectomy.
Postmenopausal women who are taking E + P to reduce bone loss should seek advice from their health care providers. The American Society for Bone and Mineral Research recommended that if combination HT was being administered to prevent or treat osteoporosis, changing to another agent, such as a bisphosphonate, should be considered. Assessment of bone density and other risk factors for fracture should help guide such decision making. Accelerated "catch-up" bone loss may occur when HT is stopped, so bone density should be monitored for several years.
The apparent reduction in risk for colorectal cancer is not sufficiently robust to recommend combination HT for preventing colorectal cancer.
Implications for Future Research
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The risk for Alzheimer disease increases exponentially after age 65, and projections based on demographics suggest as much as a fivefold increase in the number of Americans with this disease by 2030. Observational studies suggest that postmenopausal women who receive estrogen have a 50% reduction in their risk for Alzheimer disease, according to Dr. Richard Hodes of the NIA, a finding supported by in vitro studies based on responses of neuronal cells to estrogen in cell culture. The NIA plans to explore these findings with a controlled clinical trial involving women at elevated risk for this disease, paying heed to their other estrogen-associated health risks.
The National Cancer Institute (NCI) is supporting several clinical trials exploring means to prevent breast cancer, including the WHI diet component, a tamoxifen trial, and a healthy lifestyle approach, according to Dr. Leslie Ford of the NCI. Although risk for colorectal cancer was reduced in women receiving combined HT in the WHI trial, the NCI does not consider that finding robust enough to outweigh other risks associated with such treatments.
The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) supports studies to evaluate alternative means for preserving bone mass, including nitric oxide, phytoestrogens, doxycycline, and outfitting individuals with hip protectors to prevent hip fractures. Dr. Stephen Katz, Director of the NIAMS, described investigations of several combination therapies, including low-dose estrogen hormones or combinations of parathyroid hormone with other bone-strengthening agents, as well as studies involving biophysical stimuli to strengthen bones.
Many Americans are using alternative therapies, according to Dr. Stephen Straus, Director of the National Center on Complementary and Alternative Medicine (NCCAM), even though many of these materials have not been proven safe or effective. The NCCAM is supporting several small-scale clinical trials to evaluate alternative materials, such as phytoestrogens, for health effects on women. Some of these studies will help to delineate quality-of-life issues for menopausal women and will also consider safety issues involving hormone-sensitive cancer.
There is a need to develop alternative HT dose levels, other routes of administering them, or other regimens for women using combination HT to alleviate vasomotor and genitourinary menopausal symptoms, according to Dr. Duane Alexander, Director of the National Institute of Child Health and Human Development.
An Important Take-Home Message for Women and Their Health Care Providers
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