Menopausal hormone therapy and breast cancer: what is the evidence from randomized trials?

A Contemporary View of Menopausal Hormone Therapy

Enthusiasm for the use of hormones to ameliorate symptoms of perimenopause and menopause has waxed and waned over the years. Both treatment for symptoms and training of women's health care practitioners in the management of menopause have sharply declined since publication of the Women's Health Initiative initial results in 2002. Findings from that trial, which treated a population of older, asymptomatic patients, have been extrapolated over the past 21 years to all estrogen products, all menopausal women, and all delivery mechanisms. Our patients deserve a more nuanced, individualized approach. Conjugated equine estrogens and medroxyprogesterone acetate are no longer the predominant medications or medications of choice available for management of menopausal symptoms. All hormones are not equivalent any more than all antiseizure medications or all antihypertensives are equivalent; they have different pharmacodynamics, duration of action, and affinity for receptors, among other things, all of which translate to different risks and benefits. Consideration of treatment with the right formulation, at the right dose and time, and for the right patient will allow us to recommend safe, effective, and appropriate treatment for people with menopausal symptoms.

A review of mathematical modeling of bone remodeling from a systems biology perspective

Bone remodeling is an essential, delicately balanced physiological process of coordinated activity of bone cells that remove and deposit new bone tissue in the adult skeleton. Due to the complex nature of this process, many mathematical models of bone remodeling have been developed. Each of these models has unique features, but they have underlying patterns. In this review, the authors highlight the important aspects frequently found in mathematical models for bone remodeling and discuss how and why these aspects are included when considering the physiology of the bone basic multicellular unit, which is the term used for the collection of cells responsible for bone remodeling. The review also emphasizes the view of bone remodeling from a systems biology perspective. Understanding the systemic mechanisms involved in remodeling will help provide information on bone pathology associated with aging, endocrine disorders, cancers, and inflammatory conditions and enhance systems pharmacology. Furthermore, some features of the bone remodeling cycle and interactions with other organ systems that have not yet been modeled mathematically are discussed as promising future directions in the field.

The impact of medroxyprogesterone acetate on lipid profiles in Women: A time and dose-response meta-analysis of randomized controlled trials

BACKGROUND

The effect of MPA on the lipid profile and CVD risk is still controversial; hence, this comprehensive dose-response meta-analysis of randomized controlled trials was conducted to assess the effect of MPA on lipid profiles in women.

METHODS

A comprehensive search was conducted in the following databases: Web of Science, Scopus, PubMed/Medline, and Embase, up to October 20, 2023. A random-effects meta-analysis approach based on the DerSimonian and Laird method was used to compute the combined estimates of the intervention's impact on the lipid profile.

RESULTS

35 eligible studies with 58 arms were included in our meta-analyses analysis. Combined effect sizes suggested a significant effect of MPA on total cholesterol (TC) levels (WMD: -3.43 mg/dL, 95 % CI: -5.38 to -1.48, p < 0.001), HDL-C levels (WMD: -3.34 mg/dL, 95 % CI: -3.77 to -2.91, p < 0.001), and triglyceride (TG) levels (WMD: -9.13 mg/dL, 95 % CI: -10.92 to -7.33, p < 0.001). The subgroup meta-analysis revealed a more substantial reduction in TC in studies with dosages > 2.5 mg/day (WMD: -4.10 mg/dL), mean participant age lower than 60 years (WMD: -3.80 mg/dL), mean BMI lower than 25 kg/m2 (WMD: -5.61 mg/dL), duration of intervention of 12 months or more (WMD: -3.98 mg/dL), and when the baseline TC value was equal to or greater than 200 mg/dL (WMD: -4.13 mg/dL).

CONCLUSIONS

The current meta-analysis showed a statistically significant decrease in TC, TG, and HDL-C levels and a non-significant increase in LDL-C levels after MPA administration in women.

Pregnancy-associated risk factors for future cardiovascular disease - early prevention strategies warranted

We summarize convincing evidence that future cardiovascular disease (CVD) risk increases one-fold to four-fold for women with a history of pregnancy complicated by hypertensive disorders, gestational diabetes, fetal growth restriction, placental abruption and preterm birth. A concomitant occurrence of two or more complications in the same pregnancy further potentiates the risk. These women should be informed of their future CVD risks during the postpartum check-up taking place after delivery, and also, if needed, treated, for example, for persisting high blood pressure. In these women with high blood pressure, check-up should take place within 7-10 days, and if severe hypertension, within 72 h. Women without diagnostic signs and symptoms should be examined for the first time 1-2 years postpartum and then at intervals of 2-3 years for a complete CVD risk profile including clinical and laboratory assessments. Women should be informed for future CVD risks and their effective prevention with healthy lifestyle factors. Combined oral contraceptives should be avoided or used with caution. If laboratory or other clinical findings indicate, then vigorous treatments consisting of non-medical and medical (antihypertensives, statins, antidiabetic and anti-obesity therapies) interventions should be initiated early with liberal indications and with ambitious therapeutic goals. Low-dose aspirin and menopausal hormone therapy should be used in selected cases. Active control and treatment policies of these women with pregnancy-related risks will likely result in decreases of CVD occurrence in later life.

Menopausal hormone therapy and coronary heart disease: the roller-coaster history

In the USA it is estimated that more than one million women become menopausal each year. Coronary heart disease (CHD) is the leading cause of mortality in menopausal woman globally. The majority of perimenopausal to postmenopausal women experience bothersome symptoms including hot flashes, night sweats, mood liability, sleep disturbances, irregular bleeding and sexual dysfunction. While menopausal hormone therapy (HT) effectively treats most of these symptoms, use of HT has become confusing, especially related to CHD risk. Despite years of observational and retrospective studies supporting a CHD benefit and improved survival among HT users, the Heart and Estrogen/Progestin Replacement Study (HERS) and the Women's Health Initiative (WHI) raised doubts about this long-held premise. The timing hypothesis has since emerged and states that when HT is initiated in younger women, soon after menopause onset, there may be cardiovascular benefit. The following review discusses the roller-coaster history of HT use as it pertains to CHD in postmenopausal women. Studies that highlight HT's CHD benefit are reviewed and provide reassurance that HT utilized in appropriately selected younger postmenopausal women close to the onset of menopause is safe from a cardiovascular perspective, in line with consensus recommendations.

'Tis but a scratch: a critical review of the Women's Health Initiative evidence associating menopausal hormone therapy with the risk of breast cancer

ABSTRACT

Use of menopausal hormone therapy (HT) fell precipitously after 2002, largely as a result of the Women's Health Initiative's report claiming that the combination of conjugated equine estrogen (CEE) and medroxyprogesterone acetate increased breast cancer risk and did not improve quality of life. More recently, Women's Health Initiative (WHI) publications acknowledge HT as the most effective treatment for managing menopausal vasomotor symptoms and report that CEE alone reduces the risk of breast cancer by 23% while reducing breast cancer death by 40%. Their sole remaining concern is a small increase in breast cancer incidence with CEE and medroxyprogesterone acetate (1 per 1,000 women per year) but with no increased risk of breast cancer mortality. This article closely examines evidence that calls even this claim of breast cancer risk into serious question, including the WHI's reporting of nonsignificant results as if they were meaningful, a misinterpretation of its own data, and the misleading assertion that the WHI's findings have reduced the incidence of breast cancer in the United States. A generation of women has been deprived of HT largely as a result of this widely publicized misinterpretation of the data. This article attempts to rectify this misunderstanding, with the goal of helping patients and physicians make informed joint decisions about the use of HT.

Progesterone from ovulatory menstrual cycles is an important cause of breast cancer

Many factors, including reproductive hormones, have been linked to a woman's risk of developing breast cancer (BC). We reviewed the literature regarding the relationship between ovulatory menstrual cycles (MCs) and BC risk. Physiological variations in the frequency of MCs and interference with MCs through genetic variations, pathological conditions and or pharmaceutical interventions revealed a strong link between BC risk and the lifetime number of MCs. A substantial reduction in BC risk is observed in situations without MCs. In genetic or transgender situations with normal female breasts and estrogens, but no progesterone (P4), the incidence of BC is very low, suggesting an essential role of P4. During the MC, P4 has a strong proliferative effect on normal breast epithelium, whereas estradiol (E2) has only a minimal effect. The origin of BC has been strongly linked to proliferation associated DNA replication errors, and the repeated stimulation of the breast epithelium by P4 with each MC is likely to impact the epithelial mutational burden. Long-lived cells, such as stem cells, present in the breast epithelium, can carry mutations forward for an extended period of time, and studies show that breast tumors tend to take decades to develop before detection. We therefore postulate that P4 is an important factor in a woman's lifetime risk of developing BC, and that breast tumors arising during hormonal contraception or after menopause, with or without menopausal hormone therapy, are the consequence of the outgrowth of pre-existing neoplastic lesions, eventually stimulated by estrogens and some progestins.

The Women's Health Initiative randomized trials of menopausal hormone therapy and breast cancer: findings in context

IMPORTANCE AND OBJECTIVE

The menopausal hormone therapy (MHT) association with breast cancer has been controversial for more than 40 years. Most recently, findings from cohort studies have been discordant compared with those from the Women's Health Initiative (WHI) randomized trials. In cohort studies, both estrogen therapy and estrogen plus progestin were associated with higher breast cancer incidence. In contrast, in the WHI randomized trials, findings for estrogen plus progestin are concordant with cohort study reports, whereas estrogen therapy significantly reduced breast cancer incidence. In addition, concerns have been raised regarding the WHI findings from both trials. In this report, we briefly summarize findings for MHT on breast cancer from cohort studies and the WHI randomized trials. The report focus is addressing, point-by-point, concerns raised regarding the WHI findings.

METHODS

For cohort studies, we relied on the latest findings from (1) the meta-analysis of the Collaborative Group on Hormonal Factors in Breast Cancer and (2) the Million Women's Study. To identify commentaries and editorials, "Menopause" and "Climacteric" were searched from 2002 to present; PubMed and Google Scholar were searched for commentaries, editorials, and breast cancer, MHT, estrogen, conjugated equine estrogen, estradiol, "hormone replacement therapy," and "HRT."

DISCUSSION AND CONCLUSIONS

Thirty commentaries challenging WHI findings were identified. All were reviewed, and issues needing response were identified. Findings from the meta-analysis from the Collaborative Group on Hormonal Factors in Breast Cancer and the Million Women Study were summarized and compared with finding in the two WHI randomized trials evaluating estrogen therapy and estrogen plus progestin. Based on the randomized clinical trials, estrogen therapy, for women with prior hysterectomy, decreases breast cancer incidence and mortality. In contrast, estrogen plus progestin increases breast cancer incidence, which persists through two decades. Women considering estrogen plus progestin use for vasomotor symptoms should understand the breast cancer risk.

Effect of the use of prediagnosis hormones on breast cancer prognosis: MCC-Spain study

OBJECTIVE

To extend knowledge about the long-term use of hormones in hormone therapy or oral contraception as prognostic factors in breast cancer.

METHODS

The MCC-Spain project is a cohort of 1,685 women with incident breast cancer recruited in Spain. Recruitment was carried out between 2007 and 2010, and the follow-up finished in December 2017. The impact of hormone therapy or oral contraception on breast cancer prognosis was analyzed considering year of birth and menopausal status (1,095 women [65%] were postmenopausal). Hazard ratios (HRs) were estimated using Cox regression models. Death by any cause was considered as the event, and hormone therapy or oral contraception were analyzed as regressors.

RESULTS

Oral contraception use for less than 5 years shows an HR of 1.10 (95% CI, 0.75 to 1.62), whereas use for 5 or more years shows an HR of 1.46 (95% CI, 0.95 to 2.25), with a P trend of 0.01, showing a dose-dependent response. Regarding hormone therapy and restricting the analysis to postmenopausal women born between1940 and 1959, where most hormone therapy (consumption) is concentrated, the results did not show any trend.

CONCLUSION

Concerning oral contraception use, our results demonstrate that their use is related to poor prognosis in breast cancer. However, research in this field is limited and controversial, indicating the need for more research in this area. Regarding hormone therapy consumption, our results indicate no association with better prognosis, which contradicts what has previously been published.

Therapeutic roles of plants for 15 hypothesised causal bases of Alzheimer's disease

Alzheimer's disease (AD) is progressive and ultimately fatal, with current drugs failing to reverse and cure it. This study aimed to find plant species which may provide therapeutic bioactivities targeted to causal agents proposed to be driving AD. A novel toolkit methodology was employed, whereby clinical symptoms were translated into categories recognized in ethnomedicine. These categories were applied to find plant species with therapeutic effects, mined from ethnomedical surveys. Survey locations were mapped to assess how this data is at risk. Bioactivities were found of therapeutic relevance to 15 hypothesised causal bases for AD. 107 species with an ethnological report of memory improvement demonstrated therapeutic activity for all these 15 causal bases. The majority of the surveys were found to reside within biodiversity hotspots (centres of high biodiversity under threat), with loss of traditional knowledge the most common threat. Our findings suggest that the documented plants provide a large resource of AD therapeutic potential. In demonstrating bioactivities targeted to these causal bases, such plants may have the capacity to reduce or reverse AD, with promise as drug leads to target multiple AD hallmarks. However, there is a need to preserve ethnomedical knowledge, and the habitats on which this knowledge depends.

Menopausal Hormone Therapy and Breast Cancer

ABSTRACT

Associations of estrogen-alone and estrogen plus progestin with breast cancer incidence and related mortality are reviewed from observational studies (The Collaborative Group on Hormonal Factors in Breast Cancer and The Million Women Study, 2019) and the Women's Health Initiative's (2020) two randomized trials evaluating conjugated equine estrogen alone, for women with prior hysterectomy or with medroxyprogesterone acetate. Findings are generally concordant for estrogen plus progestin use with both observational and randomized studies reporting higher breast cancer incidence. Findings are discordant for estrogen-alone use where, in the WHI randomized trial, a lower incidence and lower breast cancer mortality was seen. In contrast, in the observational studies, estrogen-alone use was associated with higher breast cancer incidence and higher breast cancer mortality. Although these discordant findings are difficult to fully reconcile, we conclude with a discussion of public health implications of the available evidence on menopausal hormone therapy and breast cancer.

Menopausal Hormone Replacement Therapy and Reduction of All-Cause Mortality and Cardiovascular Disease: It Is About Time and Timing

ABSTRACT

The totality of evidence indicates menopausal hormone replacement therapy (HRT) effects are determined by timing of initiation according to age and/or time since menopause, underlying health of target tissue, and duration of therapy. Initiated in women at younger than 60 years and/or at or near menopause, HRT significantly reduces all-cause mortality and cardiovascular disease (CVD), whereas other primary CVD prevention therapies such as lipid-lowering fail to do so. The magnitude and type of HRT-associated risks, including breast cancer, stroke, and venous thromboembolism, are rare (<10 events/10,000 women), not unique to HRT, and comparable with other medications. Hormone replacement therapy is a sex-specific and time-dependent primary CVD prevention therapy that concomitantly reduces all-cause mortality, as well as other aging-related diseases with an excellent risk profile. Keeping in mind that prevention strategies must be personalized, health care providers and patients can use cumulated HRT data in making clinical decisions concerning chronic disease prevention including CVD and mortality reduction.

Hypogonadism in Women with Prader-Willi Syndrome-Clinical Recommendations Based on a Dutch Cohort Study, Review of the Literature and an International Expert Panel Discussion

Prader-Willi syndrome (PWS) is a rare neuroendocrine genetic syndrome. Characteristics of PWS include hyperphagia, hypotonia, and intellectual disability. Pituitary hormone deficiencies, caused by hypothalamic dysfunction, are common and hypogonadism is the most prevalent. Untreated hypogonadism can cause osteoporosis, which is already an important issue in PWS. Therefore, timely detection and treatment of hypogonadism is crucial. To increase understanding and prevent undertreatment, we (1) performed a cohort study in the Dutch PWS population, (2) thoroughly reviewed the literature on female hypogonadism in PWS and (3) provide clinical recommendations on behalf of an international expert panel. For the cohort study, we retrospectively collected results of a systematic health screening in 64 female adults with PWS, which included a medical questionnaire, medical file search, medical interview, physical examination and biochemical measurements. Our data show that hypogonadism is frequent in females with PWS (94%), but is often undiagnosed and untreated. This could be related to unfamiliarity with the syndrome, fear of behavioral changes, hygienic concerns, or drug interactions. To prevent underdiagnosis and undertreatment, we provide practical recommendations for the screening and treatment of hypogonadism in females with PWS.

Hormone Therapy in Menopause: Concepts, Controversies, and Approach to Treatment

Hormone therapy (HT) is an effective treatment for menopausal symptoms, including vasomotor symptoms and genitourinary syndrome of menopause. Randomized trials also demonstrate positive effects on bone health, and age-stratified analyses indicate more favorable effects on coronary heart disease and all-cause mortality in younger women (close proximity to menopause) than in women more than a decade past menopause. In the absence of contraindications or other major comorbidities, recently menopausal women with moderate or severe symptoms are appropriate candidates for HT. The Women's Health Initiative (WHI) hormone therapy trials-estrogen and progestin trial and the estrogen-alone trial-clarified the benefits and risks of HT, including how the results differed by age. A key lesson from the WHI trials, which was unfortunately lost in the posttrial cacophony, was that the risk:benefit ratio and safety profile of HT differed markedly by clinical characteristics of the participants, especially age, time since menopause, and comorbidity status. In the present review of the WHI and other recent HT trials, we aim to provide readers with an improved understanding of the importance of the timing of HT initiation, type and route of administration, and of patient-specific considerations that should be weighed when prescribing HT.

Identifying women with increased risk of breast cancer and implementing risk-reducing strategies and supplemental imaging

Breast cancer (BC) is the second most common cancer in women, affecting 1 in 8 women in the United States (12.5%) in their lifetime. However, some women have a higher lifetime risk of BC because of genetic and lifestyle factors, mammographic breast density, and reproductive and hormonal factors. Because BC risk is variable, screening and prevention strategies should be individualized after considering patient-specific risk factors. Thus, health care professionals need to be able to assess risk profiles, identify high-risk women, and individualize screening and prevention strategies through a shared decision-making process. In this article, we review the risk factors for BC, risk-assessment models that identify high-risk patients, and preventive medications and lifestyle modifications that may decrease risk. We also discuss the benefits and limitations of various supplemental screening methods.

Postmenopausal Hormone Therapy-Local and Systemic: A Pharmacologic Perspective

Every woman, if she lives long enough, will transition into menopause, and as the US population ages, women will be spending more time in a postmenopausal state than before. For postmenopausal women, the decision to initiate menopausal hormone therapy should be individualized. A thorough evaluation of the patient's cardiovascular, venous thromboembolic, cancer, and fracture risk should be considered along with the woman's quality of life. Hormone therapy exerts its therapeutic effects on vasomotor symptoms, the skeleton, and the genitourinary system independent of age since menopause and these benefits are lost once hormone therapy is stopped. Here we review the pharmacologic properties dose, formulation, mode of administration, timing of initiation, and duration of hormonal therapies in regard to optimizing benefit and minimizing risk to the patient. This discussion will focus on the effects of common hormonal therapies including estrogen (local and systemic), progesterone, estrogen receptor agonist/antagonist, and local dehydroepiandrosterone and include a brief review of compounded bioidentical hormone therapy.

Carotid Atherosclerosis Progression in Postmenopausal Women Receiving a Mixed Phytoestrogen Regimen: Plausible Parallels with Kronos Early Estrogen Replacement Study

This randomized double-blinded, placebo-controlled clinical trial evaluated the progression of intima-media thickness of common carotid artery (cIMT) and the effect of phytoestrogen therapy on atherosclerosis development in early and late postmenopausal women. The 2-year cIMT progression was evaluated in 315 early postmenopausal women aged 40-55 years and in 231 late postmenopausal women aged 60-69 years free of cardiovascular disease. B-mode ultrasound was done at baseline and after 12 and 24 months of follow-up. The study revealed no significant changes in the rate of cIMT progression in 315 early postmenopausal women. By contrast, a statistically significant difference in the rate of atherosclerosis development was observed in late postmenopausal women treated with phytoestrogens compared to placebo (p = 0.008). The rate of cIMT progression in the placebo group was 0.019 mm/year led to a significant increase of cIMT during the observation period (p = 0.012), while the rate of cIMT progression in phytoestrogen late postmenopausal recipients was 0.011 mm/year, and total change did not reach statistical significance during the follow-up period (p = 0.101). These results suggest that late postmenopausal women can be a suitable cohort for trials assessing the anti-atherosclerosis effects of phytoestrogen preparations. In particular, the beneficial effect of phytoestrogens on cIMT progression was demonstrated in late postmenopausal women.

Hierarchies of evidence applied to lifestyle Medicine (HEALM): introduction of a strength-of-evidence approach based on a methodological systematic review

BACKGROUND

Current methods for assessing strength of evidence prioritize the contributions of randomized controlled trials (RCTs). The objective of this study was to characterize strength of evidence (SOE) tools in recent use, identify their application to lifestyle interventions for improved longevity, vitality, or successful aging, and to assess implications of the findings.

METHODS

The search strategy was created in PubMed and modified as needed for four additional databases: Embase, AnthropologyPlus, PsycINFO, and Ageline, supplemented by manual searching. Systematic reviews and meta-analyses of intervention trials or observational studies relevant to lifestyle intervention were included if they used a specified SOE tool. Data was collected for each SOE tool. Conditions necessary for assigning the highest SOE grading and treatment of prospective cohort studies within each SOE rating framework were summarized. The expert panel convened to discuss the implications of findings for assessing evidence in the domain of lifestyle medicine.

RESULTS AND CONCLUSIONS

A total of 15 unique tools were identified. Ten were tools developed and used by governmental agencies or other equivalent professional bodies and were applicable in a variety of settings. Of these 10, four require consistent results from RCTs of high quality to award the highest rating of evidence. Most SOE tools include prospective cohort studies only to note their secondary contribution to overall SOE as compared to RCTs. We developed a new construct, Hierarchies of Evidence Applied to Lifestyle Medicine (HEALM), to illustrate the feasibility of a tool based on the specific contributions of diverse research methods to understanding lifetime effects of health behaviors. Assessment of evidence relevant to lifestyle medicine requires a potential adaptation of SOE approaches when outcomes and/or exposures obviate exclusive or preferential reliance on RCTs. This systematic review was registered with the International Prospective Register of Systematic Reviews, PROSPERO [CRD42018082148].