Effects of tibolone and continuous combined hormone replacement therapy on bleeding rates, quality of life and tolerability in postmenopausal women

Nonestrogen Therapies for Treatment of Genitourinary Syndrome of Menopause: A Systematic Review

OBJECTIVE

To systematically review the literature and provide clinical practice guidelines regarding various nonestrogen therapies for treatment of genitourinary syndrome of menopause (GSM).

DATA SOURCES

MEDLINE, EMBASE, ClinicalTrials.gov , and Cochrane databases were searched from inception to July 2021. We included comparative and noncomparative studies. Interventions and comparators were limited to seven products that are commercially available and currently in use (vaginal dehydroepiandrosterone [DHEA], ospemifene, laser or energy-based therapies, polycarbophil-based vaginal moisturizer, Tibolone, vaginal hyaluronic acid, testosterone). Topical estrogen, placebo, other nonestrogen products, as well as no treatment were considered as comparators.

METHODS OF STUDY SELECTION

We double-screened 9,131 abstracts and identified 136 studies that met our criteria. Studies were assessed for quality and strength of evidence by the systematic review group.

TABULATION, INTEGRATION, AND RESULTS

Information regarding the participants, details on the intervention and comparator and outcomes were extracted from the eligible studies. Alternative therapies were similar or superior to estrogen or placebo with minimal increase in adverse events. Dose response was noted with vaginal DHEA and testosterone. Vaginal DHEA, ospemifene, erbium and fractional carbon dioxide (CO 2 ) laser, polycarbophil-based vaginal moisturizer, tibolone, hyaluronic acid, and testosterone all improved subjective and objective signs of atrophy. Vaginal DHEA, ospemifene, tibolone, fractional CO 2 laser, polycarbophil-based vaginal moisturizer, and testosterone improved sexual function.

CONCLUSION

Most nonestrogen therapies are effective treatments for the various symptoms of GSM. There are insufficient data to compare nonestrogen options to each other.

[Menopause hormone treatment in practice. Postmenopausal women management: CNGOF and GEMVi clinical practice guidelines]

Menopause Hormonal Treatment (MHT) was initially developed to correct the climacteric symptoms induced by postmenopausal estrogen deficiency. In non-hysterectomized women, MHT combines estrogens and a progestogen, the latter opposing the negative impact of estrogen on endometrial proliferation. In France, and contrary to the USA and Northern European countries, MHT mainly combines 17β-estradiol, which is the physiological estrogen produced by the ovary, and progesterone or its derivative, dihydrogesterone. France has been a pioneer in the development of cutaneous administration routes (gel or transdermal patch) for estradiol, allowing better metabolic tolerance and a reduction of the risk of venous thromboembolism compared to the oral route. The choice of the doses as well as the treatment regimen is underpinned by tolerance as well as acceptance and compliance. The risk of breast cancer, which is one of the main risks of MHT, is higher with estro-progestogen combinations than with estrogens alone ; the preferential use of progesterone or dihydrogesterone being likely to limit the excess risk of breast cancer associated with MHT at least for duration of treatment of less than 5 to 7 years. The question of the optimal duration of MHT remains an issue and must take into account the initial indication of treatment as well as the benefit-risk balance, which is specific to each woman. Continuation of MHT is conditioned by the benefit-risk balance, which must be evaluated regularly, but also by the evolution of symptoms when MHT is stopped as well as menopause-related health risks or induced by MHT. After stopping MHT, it is necessary to maintain a medical follow-up to be adapted to the clinical situation of each woman and in particular, her cardiovascular and gynecological risk factors.

Tibolone as Hormonal Therapy and Neuroprotective Agent

Tibolone (TIB), a selective tissue estrogenic activity regulator (STEAR) in clinical use by postmenopausal women, activates hormonal receptors in a tissue-specific manner. Estrogenic activity is present mostly in the brain, vagina, and bone, while the inactive forms predominate in the endometrium and breast. Conflicting literature on TIB's actions has been observed. While it has benefits for vasomotor symptoms, bone demineralization, and sexual health, a higher relative risk of hormone-sensitive cancer has been reported. In the brain, TIB can improve mood and cognition, neuroinflammation, and reactive gliosis. This review aims to discuss the systemic effects of TIB on peri- and post-menopausal women and its role in the brain. We suggest that TIB is a hormonal therapy with promising neuroprotective properties.

Psychometric evaluation of electronic diaries assessing side-effects of hormone therapy

OBJECTIVES

Postmenopausal women (PMW) can experience side-effects (breast pain/tenderness and vaginal spotting/bleeding) associated with estrogen plus progestin therapies (EPTs). To assess these outcomes, the Breast Pain and Tenderness Daily Diary (BPT-DD) and the Vaginal Bleeding and Spotting Daily Diary (VBS-DD) were developed for electronic completion (eDiaries). This study evaluated the psychometric properties of the eDiaries.

METHODS

The eDiaries were completed daily for 28 days by 202 PMW experiencing breast pain/tenderness and/or vaginal spotting/bleeding while on EPTs. Confirmatory factor analysis (CFA) investigated the BPT-DD structure. Response distributions, test-retest reliability (intraclass correlation coefficient [ICC]), internal consistency (BPT-DD only), and construct validity (via known groups and convergent validity analyses) were assessed.

RESULTS

Completion rates were high: over 90% of women missed <3 daily entries. CFA supported the BPT-DD unidimensional structure (Bentler's Comparative Fit Index >0.98). BPT-DD inter-item correlations (r = 0.77-0.89) and internal consistency (Cronbach's alpha = 0.95-0.97) were high and good test-retest reliability was demonstrated (ICC ≥ 0.70). The eDiaries correlated moderately (>0.40), in a logical pattern with other instruments, supporting convergent validity. Known-groups analyses indicated both measures demonstrated significant differences between patients of differing severity (p < 0.001).

CONCLUSION

The study provides evidence of strong psychometric properties for the BPT-DD and VBS-DD to assess breast pain/tenderness and spotting/bleeding in PMW.

Short-term and long-term effects of tibolone in postmenopausal women

BACKGROUND

Tibolone is a synthetic steroid used for the treatment of menopausal symptoms, on the basis of short-term data suggesting its efficacy. We considered the balance between the benefits and risks of tibolone.

OBJECTIVES

To evaluate the effectiveness and safety of tibolone for treatment of postmenopausal and perimenopausal women.

SEARCH METHODS

In October 2015, we searched the Gynaecology and Fertility Group (CGF) Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase and PsycINFO (from inception), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) and clinicaltrials.gov. We checked the reference lists in articles retrieved.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing tibolone versus placebo, oestrogens and/or combined hormone therapy (HT) in postmenopausal and perimenopausal women.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures of The Cochrane Collaboration. Primary outcomes were vasomotor symptoms, unscheduled vaginal bleeding and long-term adverse events. We evaluated safety outcomes and bleeding in studies including women either with or without menopausal symptoms.

MAIN RESULTS

We included 46 RCTs (19,976 women). Most RCTs evaluated tibolone for treating menopausal vasomotor symptoms. Some had other objectives, such as assessment of bleeding patterns, endometrial safety, bone health, sexuality and safety in women with a history of breast cancer. Two included women with uterine leiomyoma or lupus erythematosus. Tibolone versus placebo Vasomotor symptomsTibolone was more effective than placebo (standard mean difference (SMD) -0.99, 95% confidence interval (CI) -1.10 to -0.89; seven RCTs; 1657 women; moderate-quality evidence), but removing trials at high risk of attrition bias attenuated this effect (SMD -0.61, 95% CI -0.73 to -0.49; odds ratio (OR) 0.33, 85% CI 0.27 to 0.41). This suggests that if 67% of women taking placebo experience vasomotor symptoms, between 35% and 45% of women taking tibolone will do so. Unscheduled bleedingTibolone was associated with greater likelihood of bleeding (OR 2.79, 95% CI 2.10 to 3.70; nine RCTs; 7814 women; I2 = 43%; moderate-quality evidence). This suggests that if 18% of women taking placebo experience unscheduled bleeding, between 31% and 44% of women taking tibolone will do so. Long-term adverse eventsMost of the studies reporting these outcomes provided follow-up of two to three years (range three months to three years). Breast cancerWe found no evidence of differences between groups among women with no history of breast cancer (OR 0.52, 95% CI 0.21 to 1.25; four RCTs; 5500 women; I2= 17%; very low-quality evidence). Among women with a history of breast cancer, tibolone was associated with increased risk (OR 1.5, 95% CI 1.21 to 1.85; two RCTs; 3165 women; moderate-quality evidence). Cerebrovascular eventsWe found no conclusive evidence of differences between groups in cerebrovascular events (OR 1.74, 95% CI 0.99 to 3.04; four RCTs; 7930 women; I2 = 0%; very low-quality evidence). We obtained most data from a single RCT (n = 4506) of osteoporotic women aged 60 to 85 years, which was stopped prematurely for increased risk of stroke. Other outcomesEvidence on other outcomes was of low or very low quality, with no clear evidence of any differences between the groups. Effect estimates were as follows:• Endometrial cancer: OR 2.04, 95% CI 0.79 to 5.24; nine RCTs; 8504 women; I2 = 0%.• Cardiovascular events: OR 1.38, 95% CI 0.84 to 2.27; four RCTs; 8401 women; I2 = 0%.• Venous thromboembolic events: OR 0.85, 95% CI 0.37 to 1.97; 9176 women; I2 = 0%.• Mortality from any cause: OR 1.06, 95% CI 0.79 to 1.41; four RCTs; 8242 women; I2 = 0%. Tibolone versus combined HT Vasomotor symptomsCombined HT was more effective than tibolone (SMD 0.17, 95% CI 0.06 to 0.28; OR 1.36, 95% CI 1.11 to 1.66; nine studies; 1336 women; moderate-quality evidence). This result was robust to a sensitivity analysis that excluded trials with high risk of attrition bias, suggesting a slightly greater disadvantage of tibolone (SMD 0.25, 95% CI 0.09 to 0.41; OR 1.57, 95% CI 1.18 to 2.10). This suggests that if 7% of women taking combined HT experience vasomotor symptoms, between 8% and 14% of women taking tibolone will do so. Unscheduled bleedingTibolone was associated with a lower rate of bleeding (OR 0.32, 95% CI 0.24 to 0.41; 16 RCTs; 6438 women; I2 = 72%; moderate-quality evidence). This suggests that if 47% of women taking combined HT experience unscheduled bleeding, between 18% and 27% of women taking tibolone will do so. Long-term adverse eventsMost studies reporting these outcomes provided follow-up of two to three years (range three months to three years). Evidence was of very low quality, with no clear evidence of any differences between the groups. Effect estimates were as follows:• Endometrial cancer: OR 1.47, 95% CI 0.23 to 9.33; five RCTs; 3689 women; I2 = 0%.• Breast cancer: OR 1.69, 95% CI 0.78 to 3.67; five RCTs; 4835 women; I2 = 0%.• Venous thromboembolic events: OR 0.44, 95% CI 0.09 to 2.14; four RCTs; 4529 women; I2 = 0%.• Cardiovascular events: OR 0.63, 95% CI 0.24 to 1.66; two RCTs; 3794 women; I2 = 0%.• Cerebrovascular events: OR 0.76, 95% CI 0.16 to 3.66; four RCTs; 4562 women; I2 = 0%.• Mortality from any cause: only one event reported (two RCTs; 970 women).

AUTHORS' CONCLUSIONS

Moderate-quality evidence suggests that tibolone is more effective than placebo but less effective than HT in reducing menopausal vasomotor symptoms, and that tibolone is associated with a higher rate of unscheduled bleeding than placebo but with a lower rate than HT.Compared with placebo, tibolone increases recurrent breast cancer rates in women with a history of breast cancer, and may increase stroke rates in women over 60 years of age. No evidence indicates that tibolone increases the risk of other long-term adverse events, or that it differs from HT with respect to long-term safety.Much of the evidence was of low or very low quality. Limitations included high risk of bias and imprecision. Most studies were financed by drug manufacturers or failed to disclose their funding source.

Qualitative cross-cultural exploration of breast symptoms and impacts associated with hormonal treatments for menopausal symptoms to inform the development of new patient-reported measurement tools

To explore cross-cultural experiences of women taking estrogen plus progestin therapies (EPT) and develop a symptom-based electronic diary and impact questionnaire for EPT-related breast symptoms. (1) Concept elicitation interviews were conducted with women in the US (n=14), Italy (n=15), Mexico (n=15) and China (n=15) to explore breast symptoms associated with EPT. Patients completed the Breast Sensitivity Questionnaire (BSQ) to evaluate understanding and comprehensiveness. (2) Based on concept elicitation, a 6-item eDiary (Breast Pain/Tenderness Daily Diary - BPT-DD) was generated and the BSQ modified forming the 18-item Breast Sensations Impact Questionnaire (BSIQ). (3) The measures were pilot-tested and then cognitively debriefed with US women receiving EPT. All qualitative data was subject to thematic analysis. Concept elicitation identified breast pain/tenderness, swollen breasts and sensitivity to contact as important symptoms, impacting women's emotional well-being, relationships with family/friends, social life, sleep, ability to move freely, contact, clothing and sexual activity. Experiences were relatively consistent across the country samples. Based on pilot testing and cognitive debriefing, the BPT-DD was reduced to 4 items (and renamed the Breast Pain Daily Diary - BP-DD) and the BSIQ was reduced to 13 items due to conceptual redundancy. Women taking EPT in the US, China, Mexico and Italy reported breast sensations that have a detrimental impact on quality of life. Two new measures were developed to assess the severity and impact of breast pain specific to EPT. This work highlights that EPT-related symptoms should be part of treatment decision-making, and treatments with less burdensome side effects are needed.

Safety and efficacy of tibolone and menopausal transition: a randomized, double-blind placebo-controlled trial

OBJECTIVE

To evaluate the efficacy, safety and tolerability of Tibolone use during the menopausal transition (MT).

METHODS

Sixty-five healthy women aged 40-55 years (48.5 ± 3.5 years) were recruited for a randomized, double-blind controlled trial. Thirty participants were recruited to receive oral Tibolone 2.5 mg/day - Tibolone Group (TG), and 35 participants were assigned to the Placebo Group (PG), which received one capsule of lactose/day. Both groups were treated for 12 consecutive weeks. The Blatt-Kupperman Menopausal Index (KMI) and the Greene Climacteric Scale (GCS) were used. The glycaemic and lipid profiles, biochemical measures of hepatic function and endometrial thickness were measured for safety. A daily registry of complaints related to the treatment was maintained, and anthropometric measures were obtained to assess tolerability.

RESULTS

A total of 57 women completed the study. After 12 weeks of Tibolone use, the total score and percentage of the KMI and GCS were significantly decreased compared to baseline, which reflected the efficacy of the treatment of climacteric symptoms. The improvement in blood biochemistry, endometrial atrophy and maintenance of the anthropometrical measures reflected the safety of Tibolone use. The absence of serious side effects demonstrated good tolerability for Tibolone use.

CONCLUSIONS

The results showed good efficacy, tolerability and safety of Tibolone use during the MT.

Short and long term effects of tibolone in postmenopausal women

BACKGROUND

Tibolone is an option available for the treatment of menopausal symptoms, based on short-term data on its efficacy. However, there is a need to consider the balance between the benefits and risks of tibolone as there are concerns about breast and endometrial cancer as well as stroke.

OBJECTIVES

To evaluate the effectiveness and safety of tibolone in treating postmenopausal women.

SEARCH METHODS

We searched the Cochrane Menstrual Disorders and Subfertility Group (MDSG) Specialised Register (19 April 2011), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, 2nd Quarter), MEDLINE (from inception to 19 April 2011), EMBASE (1980 to week 3 April 2011), PsycINFO (1806 to week 3 April 2011), Clinical Trials.gov (30 April 2011). Individual researchers and the current manufacturer of tibolone were contacted to identify unpublished and ongoing trials.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compared tibolone versus placebo, estrogens or combined hormone replacement therapy (HT) by assessing the percentage of women with menopausal symptoms, the severity of those symptoms and the occurrence of safety outcomes in postmenopausal women.

DATA COLLECTION AND ANALYSIS

Four review authors independently extracted information from the articles, resolving discrepancies by consensus. All outcomes studied were dichotomous. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using the random-effects model. Heterogeneity of studies was taken into account before deciding to combine the data.

MAIN RESULTS

When compared to placebo, tibolone was more effective in relieving the frequency of vasomotor symptoms (two RCTs, n = 847; OR 0.42, 95% CI 0.25 to 0.69), although only the 2.5 mg/day dose of tibolone was significantly better than placebo; but with increased vaginal bleeding (seven RCTs, n = 7462; OR 2.75, 95% CI 1.99 to 3.80). When compared to equipotent doses of combined HT, tibolone reduced vaginal bleeding (15 RCTs, n = 6342; OR 0.32, 95% CI 0.24 to 0.42) but was less effective in relieving the frequency of vasomotor symptoms (two RCTs, n = 545; OR 4.16, 95% CI 1.50 to 11.58).As for long term safety, two major RCTs of tibolone versus placebo provided the most relevant data. An RCT of 3098 women with breast cancer and menopausal symptoms was halted after 3.1 years because of increased tumour recurrence (OR 1.50; 95% CI 1.21 to 1.85). However, in another RCT that selected osteoporotic women with negative mammograms (n = 4506) tibolone was associated with a reduction in breast cancer compared to placebo after 2.8 years (OR 0.32, 95% CI 0.13 to 0.79) although the trial was not specifically designed to assess that outcome and the number of overall events was low. In the same RCT, an excess risk of stroke was observed (OR 2.18, 95% CI 1.12 to 4.21). There was no clear evidence of a tibolone effect on endometrial cancer compared with placebo given the low number of events (seven RCTs, n = 8152; OR 1.98, 95% CI 0.73 to 5.32).There was no evidence of a difference in long term safety between tibolone and combined HT.

AUTHORS' CONCLUSIONS

Tibolone, used at the daily dose of 2.5 mg, may be less effective than combined HT in alleviating menopausal symptoms although it reduced the incidence of vaginal bleeding. There was evidence that treatment with combined HT was more effective in managing menopausal symptoms than was tibolone. Available data on the long term safety of tibolone is concerning given the increase in the risk of breast cancer in women who had already suffered from breast cancer in the past and in a separate trial the increase in the risk of stroke in women whose mean age was over 60 years. Similar concerns may exist for estroprogestins but their overall benefit-risk profile is better known and is more directly related to women with menopausal symptoms.

Breast tenderness and breast cancer risk in the estrogen plus progestin and estrogen-alone women's health initiative clinical trials

The associations between breast tenderness during use of conjugated equine estrogen (CEE) therapy with or without medroxyprogesterone (MPA) therapy and subsequent breast cancer risk are unknown. We analyzed data from the Women's Health Initiative Estrogen plus Progestin (N = 16,608, 5.6 years intervention) and estrogen-alone (N = 10,739, 6.8 years intervention) clinical trials until trial close-out (Spring 2005). At baseline and annually, participants underwent mammography and clinical breast exam. Self-reported breast tenderness was assessed at baseline and 12 months. Invasive breast cancer was confirmed by medical record review. The risk of new-onset breast tenderness after 12 months was significantly higher among women assigned to active therapy than placebo (CEE-alone vs. placebo risk ratio [RR] 2.15, 95% confidence interval [CI] 1.97-2.35; CEE + MPA vs. placebo RR 3.07, 95% CI 2.85-3.30). CEE + MPA doubled the risk of invasive breast cancer among women with baseline breast tenderness (hazard ratio [HR] 2.16, 95% CI 1.29-3.74), but had a smaller effect among women without baseline breast tenderness (HR 1.17; 95% CI 0.97-1.41). New-onset breast tenderness was associated with a higher risk of breast cancer among women assigned to CEE + MPA (HR 1.33, 95% CI 1.02-1.72, P = 0.03), but not among women assigned to CEE-alone (HR 0.98, 95% CI 0.62-1.53). New-onset breast tenderness during use of CEE + MPA was associated with increased subsequent breast cancer risk. The association of CEE + MPA therapy with increased breast cancer risk was especially pronounced among women with baseline breast tenderness.

Breast tenderness after initiation of conjugated equine estrogens and mammographic density change

We examined the association between new-onset breast tenderness and change in mammographic density after initiation of conjugated equine estrogens (CEE). We analyzed baseline, year 1 and 2 data from 695 participants of the Women's Health Initiative Estrogen + Progestin (daily CEE 0.625 mg + medroxyprogesterone acetate 2.5 mg [MPA] or placebo) and Estrogen-Alone (CEE 0.625 mg or placebo) trials who participated in the Mammogram Density Ancillary Study. Using multivariable repeated measures models, we analyzed the association between new-onset breast tenderness (i.e. absence of baseline tenderness and presence of tenderness at year 1 follow-up) and change from baseline in percent mammographic density. Active therapy increased the odds of new-onset breast tenderness (CEE + MPA vs. placebo risk ratio [RR] 3.01, 95% confidence interval [95% CI] 1.96-4.62; CEE vs. placebo RR 1.70, 95% CI 1.14-2.53). Among women assigned to CEE + MPA, mean increase in mammographic density was greater among participants reporting new-onset of breast tenderness than among participants without new-onset breast tenderness (11.3 vs. 3.9% at year 1, 9.4 vs. 3.2% at year 2, P < 0.001). Among women assigned to CEE alone, increase in mammographic density at year 1 follow-up was not significantly different in women with new-onset breast tenderness compared to women without new-onset breast tenderness (2.4 vs. 0.6% at year 1, 2.2 vs. 1.0% at year 2, P = 0.30). The new-onset of breast tenderness after initiation of CEE + MPA, but not CEE alone, is associated with greater increases in mammographic density.

Tibolone in postmenopausal women: a review based on recent randomised controlled clinical trials

AIM

To critically discuss the use of tibolone (T), in light of a series of very recent double-blind placebo (PL) controlled trials (LISA, LIFT, OPAL, THEBES, LIBERATE) conducted worldwide in a large number of postmenopausal women (PMW).

METHODS

The most relevant publications on T therapy in PMW were considered with emphasis on menopausal symptoms, quality of life, sexuality, bone, cardiovascular system (CVS) and oncologic risk.

RESULTS

T significantly relieves climacteric symptoms and improves mood and sexual well-being (LISA). T is as effective as estrogen-progestin therapy in preventing bone loss and reducing the relative risk of vertebral and non-vertebral fractures (LIFT). By using surrogate endpoints of the individual risks for the CVS, studies show mixed results, but a favourable effect on acute miocardial infarction and thromboembolism has been documented (THEBES, LIFT, OPAL). Although findings about endometrial and colon cancer are reassuring, conclusive data on breast cancer risk with T are not available and an increased risk of recurrence in women with previous breast cancer emerged (LIBERATE).

CONCLUSIONS

T is effective in treating menopausal syndrome with a good tolerability profile. In spite of some unsolved issues in term of safety, T is still a good treatment option for early PMW.

Updated clinical recommendations for the use of tibolone in Asian women

Tibolone, which is indicated for the relief of climacteric symptoms and the prevention of osteoporosis in postmenopausal women, has a tissue-specific mode of action different to that of conventional hormone replacement therapy (HRT). A large proportion of Asian postmenopausal women experience symptoms that most frequently include musculoskeletal pain, insomnia, forgetfulness, hot flushes and sexual dysfunction, and there is a need to address their specific requirements. Recent studies show that, in comparison to HRT, tibolone is as effective in alleviating menopausal symptoms and preventing bone loss, has a greater positive effect on sexual dysfunction and is associated with less vaginal bleeding, but it is rarely mentioned in guidelines for menopausal treatment. Levels of awareness amongst women about treatments for menopausal symptoms vary between Asian countries but, even in countries where awareness is high, HRT usage is much lower than in the West. To provide a practical approach to the use of tibolone in Asian postmenopausal women, a panel of experts in the management of menopause from 11 Asia Pacific countries has developed recommendations for its use, based on the evidence from clinical studies published since 2005. However, as much of the clinical data reviewed are from international studies, the recommendations and the treatment algorithm presented here are widely applicable.

Chinese medicinal herbs in relieving perimenopausal depression: a randomized, controlled trial

OBJECTIVE

To explore the effects of GengNianLe (GNL, also called perimenopausal depression relieving formula), a defined formula of Chinese medicinal herbs in relieving perimenopausal depression in Chinese women.

METHODS

Between September 2004 and April 2008, 47 Chinese women were randomized into a GNL group (n = 21) and a control group which received tibolone (n = 26) using a randomization chart. Depression was rated with the 24-item Hamilton Depression Scale (HAMD). The serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E(2)) were detected before and after the treatment.

RESULTS

After 12 weeks of treatment, HAMD scores in both groups decreased significantly (p < 0.05) with no significant difference between the groups (p > 0.05). The levels of FSH decreased significantly and the level of E(2) increased significantly in both groups, and they changed more in the control group. No side-effect of treatment was reported in either group during treatment.

CONCLUSIONS

The Chinese medicinal formula GNL showed promise in relieving perimenopausal depression and merits further study.

Bazedoxifene/conjugated estrogens and quality of life in postmenopausal women

OBJECTIVE

To assess the effects of bazedoxifene/conjugated estrogens (BZA/CE) on sleep parameters and health-related quality of life (HR-QOL).

METHODS

This was a 12-week, multicenter, double-blind, placebo-controlled phase 3 study. Postmenopausal women with an intact uterus and experiencing >or=7 moderate-to-severe hot flushes daily were randomized to BZA 20 mg/CE 0.45 mg, BZA 20 mg/CE 0.625 mg, or placebo. In these secondary efficacy analyses, the Medical Outcomes Study (MOS) sleep scale and Menopause-Specific Quality of Life (MENQOL) questionnaires and the Menopause Symptoms Treatment Satisfaction Questionnaire (MS-TSQ) evaluated measures of sleep, menopausal symptoms, and satisfaction with treatment, respectively.

RESULTS

A total of 318 subjects (mean age, 53.4 years) received >or=1 dose of study drug. At Week 12, BZA 20 mg/CE 0.45 and 0.625 mg showed significant improvements over placebo in the MOS sleep scale for time to fall asleep, sleep adequacy, sleep disturbance, and sleep problems indexes I and II (P<0.001). A reduction in hot flush frequency was significantly associated with improvement in sleep parameters (P<0.05) based on linear regression and responder analyses. Both BZA/CE doses showed significantly greater improvements over placebo in vasomotor function and total MENQOL score (P<0.001). Results of the MS-TSQ showed that subjects treated with BZA/CE versus placebo reported significantly greater overall satisfaction with treatment (P<0.05), as well as greater satisfaction with sleep quality, ability to control hot flushes during the day and night, effect on mood/emotions, and tolerability.

CONCLUSION

Symptomatic postmenopausal women treated with BZA/CE experienced significant improvements in sleep parameters and overall HR-QOL.

Clinical effects of tibolone in postmenopausal women after 5 years of tamoxifen therapy for breast cancer

OBJECTIVES

This observational, prospective, open, non-randomized study was designed to assess the safety and efficacy of tibolone for the treatment of climacteric symptoms in women with a history of breast cancer.

METHODS

A total of 156 women who had been treated for breast cancer and had received tamoxifen for 5 years participated in the study. One month after stopping tamoxifen, 52 women started taking tibolone while the rest served as untreated controls (n = 104). They were followed up (mean duration 61 months) for climacteric symptoms, cancer recurrence rate, breast density, endometrial thickness and adverse events.

RESULTS

There was no difference in cancer recurrence rate between the two groups. Breast density was not affected. Tibolone treatment alleviated climacteric symptoms and positively affected sexual problems. Endometrial thickness was not adversely affected by treatment and there was a low incidence of adverse events.

CONCLUSIONS

Tibolone was effective in the treatment of climacteric symptoms and well tolerated in a group of 52 women with a history of breast cancer. The cancer recurrence rate in the tibolone group was comparable to that of untreated controls. It should be noted that the limitations of the study design and the small number of events preclude any definitive conclusions about the effects of tibolone on breast cancer recurrence in general clinical practice. There were no breast-related adverse effects, and overall safety and tolerance were similar to those of the general population of postmenopausal women treated with tibolone.

Tibolone: the way to beat many a postmenopausal ailments

OBJECTIVE

The effects of tibolone on climacteric symptoms, osteoporosis, cardiovascular disease, breasts and the endometrium are summarised, and its role in clinical practice is reviewed in this article.

BACKGROUND

Tibolone has tissue-specific effects on receptors and enzymes that influence the synthesis and metabolism of endogenous sexual steroid hormones.

METHODS

This evaluation was based on the findings from several randomised studies, which addressed the basic and clinical research on tibolone.

RESULTS/CONCLUSION

Clinical trials prove that tibolone is effective in the treatment of the menopausal symptoms and for the postponement and calming of symptoms accompanying age-related diseases. The findings of basic researchers that tibolone affects the metabolism of every cell, including malignant cells, opened a door to a whole new domain of research that has a promising future.

Economic impact of Tibolone compared with Continuous-Combined Hormone Replacement Therapy in the management of climacteric symptoms in postmenopausal women

BACKGROUND

Deciding whether to treat postmenopausal women suffering from climacteric symptoms with Continuous Combined Hormone Replacement Therapy (CCHRT) has become increasingly difficult after the release of the Women's Health Initiative results. As a result, development of alternatives to CCHRT is required. Tibolone, which is a synthetic steroid that has estrogenic, progestogenic and androgenic properties, is reported to be a promising alternative. It has been used in Europe, in the same indication as CCHRT, for approximately 20 years but is not yet available in Canada.

OBJECTIVE

We carried out a cost-utility analysis comparing a 3-year-treatment course with Tibolone 2.5mg and conjugated equine estrogens (CEE)/medroxyprogesterone acetate (MPA) (0.625 mg/2.5 mg) in the management of postmenopausal women with climacteric symptoms.

METHODS

A Markov model, considering persistence, vaginal bleeding and climacteric symptoms, was elaborated to compare the different options in terms of cost and Quality Adjusted Life Years (QALYs), according to a public third-party payer perspective.

RESULTS

Compared with CEE/MPA, Tibolone led to an increase in cost (dollars 485 for Tibolone versus dollars 232 for CEE/MPA) and a slight increase in QALYs (2.08 for Tibolone versus 2.05 for CEE/MPA). Consequently, the incremental cost per QALY gained ratio was dollars 9198.

CONCLUSION

According to the results, Tibolone seems to be a cost-effective alternative to CEE/MPA. However, those results should be interpreted with caution insofar as the difference in terms of QALY is clinically difficult to value and taking into account the limited data on Tibolone's long-term innocuity.

Effects of tibolone and raloxifene on health-related quality of life and sexual function

OBJECTIVES

Study to compare the effects of tibolone and raloxifene on health-related quality of life, sexuality and vaginal atrophy.

METHODS

A double-blind, randomized study was conducted in 308 osteopenic, but otherwise healthy, postmenopausal women (mean age 66 years) who received tibolone 1.25mg/day or raloxifene 60 mg/day for 2 years. Health-related quality of life was assessed by the women's health questionnaire (WHQ), sexual function by the McCoy female sexuality questionnaire (MFSQ) and vaginal atrophy by assessing the karyopycnotic index (KI) and vaginal maturation (VM).

RESULTS

At week 104, the tibolone group showed a trend towards an improved health-related quality of life (HRQoL) mean score in eight out of nine WHQ domains. HRQoL scores approximated values for premenopausal women, being pre-defined as "clinically relevant". The raloxifene group showed a trend to a diminished HRQoL mean score from baseline to week 104. No difference could be assessed between the tibolone and raloxifene group in mean total score and separate domains' scores of the MFSQ, except for the vaginal lubrication domain (p=0.037). The increase in KI and VM was statistically significantly greater with tibolone than with raloxifene (for both KI and VM p<0.0001). Tibolone and raloxifene were equally well tolerated.

CONCLUSIONS

In older postmenopausal women, tibolone treatment showed a trend towards an improvement in quality of life and sexuality when compared to raloxifene.

Endometrial effects of tibolone

BACKGROUND AND OBJECTIVES

The Tibolone Histology of the Endometrium and Breast Endpoints Study is a multicenter, randomized, double-blind study designed to address the conflicting reports in the literature about the endometrial safety of tibolone (1.25 or 2.5 mg/d). Tibolone was compared with continuous combined conjugated equine estrogen (CEE) plus medroxyprogesterone acetate (MPA) (0.625 + 2.5 mg/d).

METHODS

Subjects were randomized in a 1:1:2 ratio to tibolone 1.25 mg/d, 2.5 mg/d, and CEE/MPA, respectively. The one-sided 95% confidence interval (CI) has been evaluated for the incidence of abnormal endometrial histology (hyperplasia or carcinoma) and hyperplasia and carcinoma separately for each of the two treatment groups and the treatment groups combined after 1 and 2 yr of treatment with tibolone, compared with CEE/MPA.

RESULTS

A total of 3240 women were randomized, with 3224 receiving at least one dose of study medication. The incidence and upper one-sided 95% CI for the incidence of abnormal endometrium (hyperplasia or carcinoma), and hyperplasia and carcinoma separately, were calculated at end point, yr 1, and yr 2. The incidence (upper one-sided 95% CI) of abnormal endometrium at end point was 0.0 (0.5), 0.0 (0.4), and 0.2 (0.5) in the tibolone 1.25 mg, 2.5 mg, and CEE/MPA groups, respectively. During the entire treatment period, amenorrhea was reported more frequently with tibolone 1.25 mg (78.7%) and 2.5 mg (71.4%) than CEE/MPA (44.9%).

CONCLUSION

The Tibolone Histology of the Endometrium and Breast Endpoints Study results confirm previous findings that tibolone does not induce endometrial hyperplasia or carcinoma in postmenopausal women, and it is associated with a better vaginal bleeding profile than CEE/MPA.

The effect of tibolone versus 17β-estradiol on climacteric symptoms in women with surgical menopause: A randomized, cross-over study

OBJECTIVE

To compare the effectiveness of tibolone and 17beta-estradiol on climacteric symptoms, in a randomized, single-blind, cross-over study in surgically menopausal women.

MATERIAL AND METHODS

Forty surgically menopausal women were divided randomly into two groups. Group A received treatment with tibolone for 6 months, while group B received 17beta-estradiol. After 3 weeks washout period, treatment protocols were exchanged for another 6 months. The climacteric symptoms were assessed with Greene Climacteric Scale at baseline, during washout and after the treatments. Statistical analysis was done with the Wilcoxon's Sign Rank test.

RESULTS

Both treatments significantly improved the scores of all subscales with respect to baseline. However, the improvement in psychological, somatic and sexual subscales were significantly superior in the tibolone group compared with 17beta-estradiol group. Both treatments showed comparable improvements in the relief of vasomotor symptoms.

CONCLUSION

Our findings suggest that tibolone may improve mood, libido and somatic symptoms in surgically menopausal women to a greater extent than estrogen therapy alone.

Effects of tibolone and continuous combined conjugated equine estrogen/medroxyprogesterone acetate on the endometrium and vaginal bleeding: results of the OPAL study

OBJECTIVES

The primary objective of the Osteoporosis Prevention and Arterial effects of tiboLone study was to compare the effect of tibolone and placebo on the progression of the common carotid artery intima-medial thickness; the common carotid artery intima-medial thickness and bone data will be presented elsewhere. A secondary objective was to assess the effects of tibolone (2.5 mg), continuous combined conjugated equine estrogen/medroxyprogesterone acetate [0.625/2.5 mg], and placebo on the endometrium and vaginal bleeding; these results are the subject of this report.

STUDY DESIGN

This 3-year, three-arm, international, randomized, double-blind, parallel group, placebo-controlled clinical trial enrolled 866 postmenopausal women (aged 45-79 years). The endometrium was assessed by annual transvaginal ultrasound scans and end-of-study biopsies (United States/United Kingdom centers only). Vaginal bleeding was recorded in daily diaries.

RESULTS

Endometrial thickness measured by transvaginal ultrasound scan increased slightly during the first year with tibolone and conjugated equine estrogen/medroxyprogesterone acetate, without any further progression. After 3 years, there were no significant differences between the tibolone, conjugated equine estrogen/medroxyprogesterone acetate, and placebo groups in the incidence of proliferation (1.4%, 4.8%, and 0%, respectively), endometrial hyperplasia (0% in all groups), or cancer (1, 0, and 1 case, respectively). During the first 3 months, bleeding/spotting rates were greater with conjugated equine estrogen/medroxyprogesterone acetate (48%) than with tibolone (18%; P < .001) or placebo (3%; P < .001). During 3 years of treatment, the incidence of bleeding/spotting was 66%, 48%, and 23% for conjugated equine estrogen/medroxyprogesterone acetate, tibolone, and placebo, respectively. The mean number of bleeding/spotting days was greater in the conjugated equine estrogen/medroxyprogesterone acetate than the tibolone or placebo groups (61, 28, and 7 days, respectively; P = .023 vs tibolone; P < .0001 vs placebo). The mean number of bleeding/spotting episodes was also greater in the conjugated equine estrogen/medroxyprogesterone acetate group (13 episodes) compared with the tibolone group (six episodes; P < .001) and placebo group (four episodes; P < .001). Vaginal bleeding was more commonly reported as an adverse event with conjugated equine estrogen/medroxyprogesterone acetate than tibolone (26.4% vs 10.8%, P < .0001) and as the reason for premature discontinuation (9% vs 2%, P = .001).

CONCLUSION

Compared with conjugated equine estrogen/medroxyprogesterone acetate, tibolone has a better tolerability profile with respect to vaginal bleeding but with a similar endometrial safety. These results reinforce the endometrial safety profile of tibolone.

Lack of aromatisation of the 3-keto-4-ene metabolite of tibolone to an estrogenic derivative

Tibolone is used for the treatment of climacteric symptoms in postmenopausal women. It is metabolised in a tissue-specific manner so that while some metabolites exert estrogenic effects on bone and the CNS, others are thought to protect the breast and endometrium from estrogenic stimulation. Tibolone is a 7alpha-methyl derivative of 19-norethynodrel. Since the introduction of synthetic progestagens for therapeutic use there has been considerable controversy as to whether they can undergo aromatisation to give rise to the potent estrogen, ethinylestradiol. In this study, we examined whether the delta-4-ene (7alpha-methyl norethisterone) metabolite of tibolone, which has a similar delta-4-ene A-ring structure to that of the estrone precursor, androstenedione, could undergo aromatisation to the potent estrogen, 7alpha-methyl ethinylestradiol. For these studies, JEG-3 choriocarcinoma cells were employed as they have a very high level of aromatase activity. TLC and HPLC procedures were developed to separate phenolic from non-phenolic compounds and were initially used to confirm that JEG-3 cells readily aromatised androstenedione to estrogens (up to 74%). The aromatisation of androstenedione to estrogens by these cells could be completely blocked with the potent aromatase inhibitor letrozole. When [(3)H] 7alpha-methyl norethisterone was incubated with JEG-3 cells no evidence for its conversion to [(3)H] 7alpha-ethinylestradiol was obtained. Radioactivity detected on the TLC plate or HPLC fractions where standard 7alpha-methyl ethinylestradiol was located, revealed that similar levels were present when 7alpha-methyl norethisterone was incubated with culture medium alone or with JEG-3 cells in the absence or presence of letrozole. From these investigations, it is concluded that 7alpha-methyl norethisterone does not undergo aromatisation to an estrogenic derivative.

Therapeutic effects of progestins, androgens, and tibolone for menopausal symptoms

Therapeutic strategies using progestins, androgens, and synthetic steroids such as tibolone are based on the understanding that estrogen, progesterone, and androgen receptors are localized to reproductive target tissues, brain, and bone. Unfortunately, these sex steroid receptors are widely distributed and localized to other tissues, often resulting in unintended effects. Progestins at high doses have been shown to be effective at reducing hot flashes by approximately 80% to 90%. Side effects include weight gain, mastalgia, fluid retention, vaginal discharge, and dry mouth. Dehydroepiandrosterone (DHEA), an adrenal-derived androgen, can be considered a prohormone that is peripherally converted to more potent androgens and estrogens. In studies with small numbers of subjects, DHEA has been reported to reduce vasomotor symptoms, increase sexual arousal, and improve cognitive performance. With regard to use of other androgens, there are no current testosterone preparations approved by the US Food and Drug Administration (FDA) for use in menopausal women. In phase 3 trials, a testosterone transdermal matrix patch has been shown to be effective in treatment of hypoactive sexual desire disorder in menopausal women on estrogen therapy. Tibolone, a synthetic steroid with estrogenic, androgenic, and progestational properties has been shown to be effective in the treatment of vasomotor symptoms and in preserving bone density, and it may provide positive effects on sexual function. The beneficial effects of these compounds in the menopausal woman for treatment of vasomotor symptoms, general well-being, cognitive deficits, bone loss, mood disorders, and sexual function are discussed. The overall clinical trial evidence for benefits and side effects also is presented.

Where are we with postmenopausal hormone therapy in 2005?

Recently, two large randomized placebo-controlled studies on long-term postmenopausal hormone replacement therapy, the Heart and Estrogen/progestin Replacement Study (HERS) and the Women's Health Initiative (WHI), have raise a lot of controversies, especially on the cardiovascular aspects. We briefly review these two trials and discuss what we know and do not know about postmenopausal hormone therapy, including the evidence on novel choices such as raloxifene and tibolone.

A randomized, placebo-controlled trial on the effects of soy protein containing isoflavones on quality of life in postmenopausal women

OBJECTIVE

Postmenopausal estrogen decline is implicated in several age-related physical and psychological changes in women, including decreases in perceived quality of life (QoL). A number of trials with hormone therapy showed beneficial effects of the intervention on parameters of quality of life. However, because of known or suspected serious side-effects of conventional hormone therapy there is a need for alternatives.

DESIGN

We conducted a double-blind randomized placebo-controlled trial with soy protein, containing 52 mg genistein, 41 mg daidzein, and 6 mg glycitein (aglycone weights), or milk protein (placebo) daily for 1 year. For this trial, we recruited 202 postmenopausal women aged 60 to 75 years.

RESULTS

At baseline and at final visit, participants filled in the Short Form of 36 questions (SF-36), the Questionnaire on Life Satisfaction Modules (QLS(M)), and the Geriatric Depression Scale (GDS). For the placebo group scores on all dimensions of the SF-36 and the QLS(M) decreased during the intervention year, except for the dimension "role limitations caused by physical problems." The soy group showed increases on two dimensions of the SF-36 ("social functioning" and "role limitations caused by physical problems") and on one dimension of the QLS(M). There were however no statistically significant differences in changes of scores between the two intervention groups. For the GDS similarly, no significant differences were found between the groups.

CONCLUSIONS

In conclusion, the findings in this randomized trial do not support the presence of a marked effect of soy protein substitution on quality of life (health status, life satisfaction, and depression) in elderly postmenopausal women.

Tibolone: Clinical recommendations and practical guidelines

An international multidisciplinary panel of experts in the management of the menopause met at the 4th Amsterdam Menopause Symposium in October 2004 to determine the specific place of tibolone, a synthetic steroid with a unique clinical profile, within the wide range of currently available postmenopausal therapy options. The consensus was that tibolone is a valuable treatment option for women with climacteric complaints. As well as relieving vasomotor symptoms, tibolone has positive effects on sexual well-being and mood, and improves vaginal atrophy and urogenital symptoms. Prevention of bone loss with tibolone is comparable to that seen with estrogen therapy (ET) and estrogen/progestogen therapy (EPT). As tibolone rarely causes endometrial proliferation, no additional progestogen is required. It also has good tolerability, being associated with a low incidence of vaginal bleeding and of breast pain. Tibolone does not increase mammographic density. Absolute numbers of women at increased risk for breast cancer are estimated to be low or absent with both tibolone and ET, and the risk with tibolone should be significantly lower than that with EPT. Tibolone might therefore be preferable to EPT in certain women who have not been hysterectomised. Based on the evidence available, the panel proposed a number of subgroups of postmenopausal women with vasomotor symptoms in whom tibolone might have added value; these included women with sexual dysfunction, mood disorders, fibroids and urogenital complaints, as well as those with breast tenderness or high mammographic breast density with EPT use.

Tibolone relieves climacteric symptoms in highly symptomatic women with at least seven hot flushes and sweats per day

OBJECTIVE

To establish the potency of four dose levels of tibolone, a tissue selective estrogenic activity regulator (STEAR), to relieve climacteric symptoms in a subgroup of highly symptomatic women experiencing a minimum of seven hot flushes and sweats per day.

METHODS

In a group of 770 women receiving tibolone 0.625, 1.25, 2.5 or 5.0 mg or placebo for 12 weeks, a total of 317 women experienced at least seven hot flushes and sweats per day. Frequency and intensity of climacteric symptoms were assessed at baseline and after 4, 8 and 12 weeks of treatment. Vaginal bleeding/spotting was studied using diary cards. Occurrence of adverse events was determined by active questioning.

RESULTS

Tibolone induced a decrease in the frequency and intensity of climacteric symptoms, leading to statistically significant differences compared to placebo for dose levels of 1.25 mg and higher. The incidence of vaginal bleeding/spotting and of drug-related adverse events was similar in all tibolone dose groups, except for the 5.0 mg group, where the incidence was about twice as high. Dropout rate due to insufficient therapeutic effect is substantially higher in the 0.625 and 1.25 mg group (about 10%) compared to the 2.5 and 5.0 mg group (about 1%). These results are consistent with what occurred in the total study population published previously.

CONCLUSION

The effects of tibolone in highly symptomatic women experiencing at least seven hot flushes and sweats per day do not differ much from that in the total study population. A daily dose of 2.5 mg is the optimal dose for both the total study population and the subgroup of highly symptomatic women. However, in order to optimise individual treatment, the 1.25 mg dose might also be taken into consideration.

The effect of tibolone in postmenopausal women receiving tamoxifen after surgery for breast cancer: a randomised, double-blind, placebo-controlled trial

OBJECTIVE

To assess the effects of tibolone on climacteric symptoms, endometrium and serum lipid/lipoproteins in postmenopausal women receiving tamoxifen after surgery for breast cancer.

DESIGN

Double-blind, randomised, placebo-controlled, multicentre pilot study.

SETTING

Hospital outpatient clinic.

SAMPLE

Seventy postmenopausal women receiving tamoxifen following surgery for early breast cancer.

METHODS

Women received 20 mg/day oral tamoxifen plus either 2.5 mg/day oral tibolone or placebo for 12 months.

MAIN OUTCOME MEASURES

Frequency and severity of hot flushes (diary cards); intensity of hot flushes and sweats (Landgren scale); interference of hot flushes and sweats with normal life; frequency and intensity of other climacteric symptoms; endometrial thickness and histology; vaginal bleeding; breast cancer recurrence and serum lipid/lipoproteins.

RESULTS

Daily card data showed no change in the daily number of hot flushes with either tibolone or placebo (P= 0.219) after three months. There was a significant reduction in the severity of flushes with tibolone compared with placebo (-0.4 vs 0.2, P= 0.031). The Landgren scale showed a mean change in the number of hot flushes of -0.6 with tibolone and +1.1 with placebo after 12 months (P= 0.022). Endometrial biopsies were normal and vaginal bleeding was similar in both groups. A significant decrease in triglycerides (-23% vs 1.4%) and HDL (-12% vs 19%) was seen with tibolone compared with placebo after 12 months.

CONCLUSIONS

Tibolone prevented an increase in hot flushes in postmenopausal women given tamoxifen following surgery for breast cancer without untoward effects on the endometrium. Beneficial effects on serum lipid profile were noted.

In vivo and in vitro estrogenic and progestagenic actions of Tibolone

Estrogen and progestin combination in hormone replacement therapy (HRT) increases the incidence of breast cancer, but decreases the endometrial cancer risk of unopposed estrogen. Therefore, a SERM such as Tibolone, that delivers the beneficial, but not the adverse side effects, of steroid hormones would be clinically advantageous. However, data from the Million Women Study suggests that Tibolone increases the risk of both breast and endometrial cancer. Herein, we assessed the estrogenic and progestagenic actions of Tibolone using transvaginal sonography studies and an in vitro model of breast (ZR-75, MCF7) and endometrial cancer (Ishikawa). The known cancer associated proteins (ER, EGFR, STATS, tissue factor and Bcl-xL) were selected for study. Transvaginal sonography demonstrated that postmenopausal women treated with Tibolone displayed a thinner endometrium than in the late proliferative phase, but had a phenotype characteristic of the secretory phase, thus demonstrating the estrogenic and progestagenic actions of this SERM. In vitro, Tibolone acted as an estrogen in downregulating ER and upregulating Bcl-xL, yet as progesterone, increasing STAT5 and tissue factor in breast cancer cells. The increase in tissue factor by Tibolone correlated with its coagulative potential. Interestingly, EGFR was up-regulated by progesterone in the breast and by estrogen in endometrial cells, while Tibolone increased protein levels in both cell types. In conclusion, this study further demonstrates the estrogenic and progestagenic nature of Tibolone. The pattern of regulation of known oncogenes in cells of breast and endometrial origin dictates caution and vigilance in the prescription of Tibolone and subsequent patient monitoring.

Postmenopausal hormone therapy: impact on menopause-related symptoms, chronic disease and quality of life

Quality of life in climacteric and postmenopausal women is often compromised. This overview addresses the many factors that may interfere with health and well-being in such women. Hormonal changes during the menopausal transition, finally resulting in estrogen deficiency, play a pivotal role in the incidence of climacteric symptoms and also in the development of chronic diseases. Such symptoms and diseases can contribute to impaired quality of life in climacteric and postmenopausal women. Postmenopausal hormone therapy (PHT) is the treatment of first choice to alleviate symptoms of estrogen deficiency. Besides effectively relieving climacteric symptoms and complaints, PHT can also protect against some chronic diseases, such as osteoporosis and colorectal cancer. Presently, available PHTs vary widely in type, estrogen and progestogen dosage, and route and duration of administration. Furthermore, the number of alternatives to treat climacteric symptoms, and/or to prevent chronic diseases, has increased. Therefore, doctors involved in the care of climacteric women in the 21st century are much more able to meet the specific needs of individual patients and improve health and quality of life.

Postmenopausal hormone therapy before and after breast cancer: clinical experiences

Conventional oestrogen-based hormone therapy (HT) increases the incidence of breast pain and tenderness, mammographic density and the risk of breast cancer. Combined oestrogen plus progestogen therapy (EPT) increases the risk of breast cancer to a greater degree than oestrogen alone (ET). Attention must therefore be focused on identifying women at risk of breast cancer or on producing a HT that has fewer breast side effects. Randomised controlled trials have shown that while EPT induces breast tenderness or pain in up to 50% of women and increases mammographic density in up to 70% during the first year of treatment, only about as many as one-tenth women report breast tenderness or pain with tibolone and increases in mammographic density are rare, occurring with a similar incidence as seen in untreated controls. Many women with breast cancer suffer vasomotor symptoms rather than risk recurrence with conventional HT. However, in a small randomised controlled trial in women with early breast cancer undergoing adjuvant tamoxifen treatment, tibolone reduced hot flushes, night sweats and improved quality of life compared with placebo.

Tissue-selectivity: the mechanism of action of tibolone

Tibolone is effective in preventing bone loss and treating climacteric symptoms, without stimulating the endometrium. The effects on bone, brain and vagina can be accurately explained by the oestrogenic activity of tibolone, but oestrogenic activity is not expressed in the endometrium. Tibolone behaves differently from oestrogen plus progestogen combinations on the breast. Therefore, tibolone can be characterised as a selective oestrogen activity regulator. The objective of this review is to characterise the typical properties of tibolone in order to explain its tissue-selective action. Tibolone is rapidly converted into three major metabolites: 3 alpha- and 3 beta-hydroxy-tibolone, which have oestrogenic effects, and the Delta(4)-isomer, which has progestogenic and androgenic effects. The 3-hydroxy metabolites are present in the circulation, predominantly in their inactive sulphated form. The tissue-selective effects of tibolone are the result of metabolism, enzyme regulation and receptor activation that vary in different tissues. The bone preserving effects are the result of oestradiol receptor activation, whilst other steroid receptors, notably the progesterone and androgen receptor, are not involved. Breast tissue of monkeys is not stimulated, as occurs with oestrogen plus progestogen, because tibolone and its metabolites inhibit sulphatase and 17 beta-hydroxysteroid dehydrogenase (HSD) type I and stimulate sulphotransferase and 17 beta-HSD type II, the combined effects of which prevent conversion to active oestrogens. In addition, tibolone affects cellular homeostasis in the breast by inhibiting proliferation and stimulating apoptosis. Tibolone does not stimulate the endometrium because of the action of the highly stable progestogenic metabolite (Delta(4)-isomer) in combination with an effect on the sulphatase (inhibition)-sulphotransferase (stimulation) system. The oestrogenic metabolites of tibolone have direct favourable effects on the cardiovascular system and, in in vivo models, tibolone has shown no adverse consequences. In conclusion, tibolone shows oestrogenic effects in brain, vagina and bone and has direct oestrogenic effects on the cardiovascular system. In the endometrium, the progestogenic activity of the Delta(4)-metabolite and the effect on oestrogen-inactivating enzymes prevent oestrogenic stimulation. The mammary gland is not stimulated in currently used animal models. Tibolone appears to regulate estrogenic activity in the various tissues by influencing the availability of estrogenic compounds for the estradiol receptor in a tissue-selective manner.

A comparative review of the risks and benefits of hormone replacement therapy regimens

The Women's Health Initiative (a large, randomized, placebo-controlled trial) investigated the effect of conjugated equine estrogens combined with medroxyprogesterone acetate on specific potential long-term benefits and risks. A review of the clinical studies that have investigated different types and regimens of estrogens combined with progestins was conducted to assess how applicable the results of the Women's Health Initiative are to hormone replacement therapy regimens in general. The studies that were reviewed were limited to randomized clinical trials and observational studies that have been published over the last 15 years (1987-2002) and to meta-analyses and reviews that may have included the literature before 1987. The increased risks for venous thromboembolism, stroke, coronary heart disease, and breast cancer that were identified in the Women's Health Initiative trial have also been reported with postmenopausal hormone therapies that contain a variety of estrogen and progestin products. The beneficial effects that were noted in the Women's Health Initiative, with respect to reductions in fractures and colorectal cancer, have not been evaluated in large, randomized controlled trials that use different estrogen/progestin combinations; however, observational trials that used a variety of estrogen or hormone replacement therapy products and randomized clinical studies that evaluated bone mineral density (an excellent predictor of fracture risk) with different estrogen/hormone replacement therapy regimens would suggest that results would be similar to those found in the Women's Health Initiative. Although the relief of menopausal symptoms, the primary reason women seek treatment, was not included in the overall benefit/risk analysis of the Women's Health Initiative, numerous trials suggest that all therapies are effective. Overall, these data indicate that the benefit/risk analysis that was reported in the Women's Health Initiative can be generalized to all postmenopausal hormone replacement therapy products.

Tibolone: A Unique Version of Hormone Replacement Therapy

OBJECTIVE

To review the pharmacology, pharmacokinetics, efficacy, and safety of tibolone in the treatment of menopausal symptoms and the prevention of osteoporosis.

DATA SOURCES

Information was obtained from a MEDLINE search (1966–July 2003) and from Organon International. The bibliographies of reviewed literature were searched for additional studies.

STUDY SELECTION AND DATA EXTRACTION

Studies and review articles evaluating tibolone were evaluated. Since tibolone has been available for many years in Europe and has an extensive literature base, this review emphasizes information from studies published after 1995.

DATA SYNTHESIS

Tibolone possesses estrogenic activity and is effective for treating the symptoms and osteoporosis associated with menopause. While the impact of tibolone on the risk of breast cancer or cardiovascular and thromboembolic events is not well defined, its unique pharmacologic profile may provide a safer alternative to traditional hormone replacement therapy. Although widely used for many years in other countries, tibolone has not been approved for use in the US.

CONCLUSIONS

Results of recent trials have led to questions regarding the safety of established hormone replacement therapies in peri- and postmenopausal women. Tibolone appears to be an attractive alternative to these traditional regimens. Additional studies will determine whether the promise of increased safety with tibolone will be realized.

Tibolone and risk of endometrial polyps: a prospective, comparative study with hormone therapy

OBJECTIVE

To assess the incidence of endometrial polyps during postmenopausal replacement therapy with tibolone, using an appropriate control group.

DESIGN

A total of 485 postmenopausal women were included in this open, prospective, comparative study for a duration of 36 months. Of this group, 249 women received 2.5 mg/day of tibolone and 244 women served as controls, receiving continuous-combined estrogen-progestogen therapy (HT). Transvaginal ultrasound, hysteroscopy, and directed biopsies were performed before treatment was initiated and at the end of the study.

RESULTS

Two hundred twenty-one of the women receiving tibolone and 203 receiving continuous-combined HT completed the study. Endometrial polyps were detected in 74 women (33.4%) from the tibolone group and in 22 women (10.8%) from the HT group (P < 0.01). The vaginal bleeding rate did not differ between the groups. The frequency of atrophic polyps was significantly higher in the tibolone group (P < 0.01). No difference was found in the size of the polyps.

CONCLUSIONS

Tibolone increases by threefold the risk for endometrial polyps.

Pros and cons of existing treatment modalities in osteoporosis: a comparison between tibolone, SERMs and estrogen (+/-progestogen) treatments

Tibolone, selective estrogen receptor modulators (SERMs) like tamoxifen and raloxifene, and estrogen (+/-progestogen) treatments prevent bone loss in postmenopausal women. They exert their effects on bone via the estrogen receptor (ER) and the increase in bone mass is due to resorption inhibition. The effect of SERMs on bone mineral density is less than that with the other treatments, but the SERM raloxifene still has a positive effect on vertebral fractures. In contrast to tibolone and estrogens (+/-progestogen), SERMs do not treat climacteric complaints, whilst estrogen plus progestogen treatments cause a high incidence of bleeding. Estrogen plus progestogen combinations have compromising effects on the breast. Tibolone and SERMs do not stimulate the breast or endometrium. Unlike SERMs, tibolone does not possess antagonistic biological effects via the ER in these tissues. Estrogenic stimulation in these tissues is prevented by local metabolism and inhibition of steroid metabolizing enzymes by tibolone and its metabolites. SERMs and estrogen (+/-progestogen) treatments increase the risk of venous thromboembolism (VTE), whilst estrogen (+/-progestogen) combinations have unwanted effects on cardiovascular events. So far, no detrimental effects of tibolone have been observed with respect to VTE or cardiovascular events. The clinical profile of tibolone therefore has advantages over those of other treatment modalities. It is also clear that tibolone is a unique compound with a specific mode of action and that it belongs to a separate class of compounds that can best be described as selective, tissue estrogenic activity regulators (STEARs).