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Hormone therapy in the postmenopausal years: considering benefits and risks in clinical practice

BACKGROUND

Menopausal symptoms can be very distressing and considerably affect a woman's personal and social life. It is becoming more and more evident that leaving bothersome symptoms untreated in midlife may lead to altered quality of life, reduced work productivity and, possibly, overall impaired health. Hormone therapy (HT) for the relief of menopausal symptoms has been the object of much controversy over the past two decades. At the beginning of the century, a shadow was cast on the use of HT owing to the concern for cardiovascular and cerebrovascular risks, and breast cancer, arising following publication of a large randomized placebo-controlled trial. Findings of a subanalysis of the trial data and extended follow-up studies, along with other more modern clinical trials and observational studies, have provided new evidence on the effects of HT.

OBJECTIVE AND RATIONALE

The goal of the following paper is to appraise the most significant clinical literature on the effects of hormones in postmenopausal women, and to report the benefits and risks of HT for the relief of menopausal symptoms.

SEARCH METHODS

A Pubmed search of clinical trials was performed using the following terms: estrogens, progestogens, bazedoxifene, tibolone, selective estrogen receptor modulators, tissue-selective estrogen complex, androgens, and menopause.

OUTCOMES

HT is an effective treatment for bothersome menopausal vasomotor symptoms, genitourinary syndrome, and prevention of osteoporotic fractures. Women should be made aware that there is a small increased risk of stroke that tends to persist over the years as well as breast cancer risk with long-term estrogen-progestin use. However, healthy women who begin HT soon after menopause will probably earn more benefit than harm from the treatment. HT can improve bothersome symptoms, all the while conferring offset benefits such as cardiovascular risk reduction, an increase in bone mineral density and a reduction in bone fracture risk. Moreover, a decrease in colorectal cancer risk is obtainable in women treated with estrogen-progestin therapy, and an overall but nonsignificant reduction in mortality has been observed in women treated with conjugated equine estrogens alone or combined with estrogen-progestin therapy. Where possible, transdermal routes of HT administration should be preferred as they have the least impact on coagulation. With combined treatment, natural progesterone should be favored as it is devoid of the antiapoptotic properties of other progestogens on breast cells. When beginning HT, low doses should be used and increased gradually until effective control of symptoms is achieved. Unless contraindications develop, patients may choose to continue HT as long as the benefits outweigh the risks. Regular reassessment of the woman's health status is mandatory. Women with premature menopause who begin HT before 50 years of age seem to have the most significant advantage in terms of longevity.

WIDER IMPLICATIONS

In women with bothersome menopausal symptoms, HT should be considered one of the mainstays of treatment. Clinical practitioners should tailor HT based on patient history, physical characteristics, and current health status so that benefits outweigh the risks.

Hormone therapy for postmenopausal osteoporosis management

Menopausal hormone therapy (MHT) has been used for prevention and treatment of postmenopausal osteoporosis for several decades. However, public concerns were raised over the safety of MHT after the initial report was published in 2002 by the Women's Health Initiative. We conducted a historical review on this subject, primarily focusing on level I evidence from randomized controlled trials, systematic reviews and meta-analyses, and summarized high-quality evidence on the efficacy and safety of MHT in management of postmenopausal osteoporosis. Clinical issues were also discussed on MHT initiation, identification of treatment candidates and treatment duration, as well as discontinuation of MHT.

Hormone therapy and breast cancer: risk communication and the 'perfect storm'

Many factors are considered when a woman estimates her personal risk of breast cancer. Common to most decisions are four separate influences that have convinced the public and many health-care providers that breast cancer is the greatest concern for menopausal women and that menopausal hormone therapy (MHT) is generally responsible. Historically there have been well-documented situations in which big pharma and doctors have not put patient interests first. Conflicting reports about the safety of MHT and the media imperative to always increase readership by presenting a compelling scary story have created an underlying distrust of science, doctors, and MHT. Numerical and statistical illiteracy in the general population creates a situation where lotteries succeed despite astronomical odds and the risks of medical interventions are exaggerated by their description using relative, rather than absolute, risks. Finally, mammographic overdiagnosis contributing to improved breast cancer survival has contributed to the 'popularity paradox' (more screening - more enthusiasm) especially among survivors and advocacy groups. As a result, worry about breast cancer has overshadowed concern about cardiovascular diseases as the major cause of death and disability in the later years. The ongoing challenge for clinicians dealing with menopausal women is to bridge the gap in risk perception with evidence-based common-sense advice.

Hormone-replacement therapy: current thinking

For several decades, the role of hormone-replacement therapy (HRT) has been debated. Early observational data on HRT showed many benefits, including a reduction in coronary heart disease (CHD) and mortality. More recently, randomized trials, including the Women's Health Initiative (WHI), studying mostly women many years after the the onset of menopause, showed no such benefit and, indeed, an increased risk of CHD and breast cancer, which led to an abrupt decrease in the use of HRT. Subsequent reanalyzes of data from the WHI with age stratification, newer randomized and observational data and several meta-analyses now consistently show reductions in CHD and mortality when HRT is initiated soon after menopause. HRT also significantly decreases the incidence of various symptoms of menopause and the risk of osteoporotic fractures, and improves quality of life. In younger healthy women (aged 50-60 years), the risk-benefit balance is positive for using HRT, with risks considered rare. As no validated primary prevention strategies are available for younger women (<60 years of age), other than lifestyle management, some consideration might be given to HRT as a prevention strategy as treatment can reduce CHD and all-cause mortality. Although HRT should be primarily oestrogen-based, no particular HRT regimen can be advocated.

Where are we 10 years after the Women's Health Initiative?

The media attention surrounding the publication of the initial results of WHI in 2002 led to fear and confusion regarding the use of hormonal therapy (HT) after menopause. This led to a dramatic reduction in prescriptions for HT in the United States and around the world. Although in 2002 it was stated that the results pertained to all women receiving HT, subsequent studies from the Women's Health Initiative (WHI) and others clearly showed that younger women and those close to menopause had a very beneficial risk-to-benefit ratio. Indeed, the results showed similar protective effects for coronary disease and a reduction in mortality that had been shown in earlier observational studies, which had also focused on younger symptomatic women. In younger women, the increased number of cases of venous thrombosis and ischemic stroke was low, rendering them "rare" events using World Health Organization nomenclature. Breast cancer rates were also low and were found to be decreased with estrogen alone. In women receiving estrogen and progestogen for the first time in the WHI, breast cancer rates did not increase significantly for 7 years. Other data suggest that other regimens and the use of other progestogens may also be safer. It has been argued that in the 10 years since WHI, many women have been denied HT, including those with severe symptoms, and that this has significantly disadvantaged a generation of women. Some reports have also suggested an increased rate of osteoporotic fractures since the WHI. Therefore, the question is posed as to whether we have now come full circle in our understanding of the use of HT in younger women. Although it is appropriate to treat women with symptoms at the onset of menopause, because there is no proven therapy for primary prevention, in some women the use of HT for this role may at least be entertained.