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

Management of unscheduled bleeding on HRT: A joint guideline on behalf of the British Menopause Society, Royal College Obstetricians and Gynaecologists, British Gynaecological Cancer Society, British Society for Gynaecological Endoscopy, Faculty of Sexual and Reproductive Health, Royal College of General Practitioners and Getting it Right First Time

Unscheduled bleeding on hormone replacement therapy (HRT) can affect up to 40% of users. In parallel with the increase in HRT prescribing in the UK, there has been an associated increase in referrals to the urgent suspicion of cancer pathway for unscheduled bleeding. On behalf of the British Menopause Society (BMS) an expert review panel was established, including primary and secondary care clinicians with expertise in the management of menopause, with representatives from key related organisations, including the Royal College of Obstetricians & Gynaecologists, the British Gynaecological Cancer Society, British Society for Gynaecological Endoscopy, Royal College of General Practitioners and Faculty of Sexual and Reproductive Health, and service development partners from NHS England and GIRFT (Getting it Right First Time). For each topic, a focused literature review was completed to develop evidence led recommendations, where available, which were ratified by consensus review within the panel and by guideline groups.

Effectiveness of Tibolone in Relieving Postmenopausal Symptoms for a Short-Term Period in Indian Women

Background

Tibolone is an alternative to conventional estrogen and progesterone in relieving post-menopausal symptoms in Indian women.

Material and Methods

A prospective short-term observational study was done at a tertiary care teaching hospital in New Delhi from November 2019 to September 2021. Fifty-three women, less than 60 years of age, presenting with moderate to severe intensity of menopausal symptoms as assessed by measuring menopausal rating score (MRS > 8) were enrolled and given Tibolone 2.5 mg daily for 3 months. Improvements in symptoms were seen at 1 month and 3 months. Side effects were also noted.

Results

Marked improvement was seen as reduction in scores of psychological, somatic and genitourinary symptoms was noted. The psychological symptoms reduced from 8.92 ± 1.959 to 2.905 ± 1.042, the somatic symptoms decreased from 8.33 ± 2.299 to 3.4 ± 1.167, and genitourinary symptoms decreased from 3.64 ± 1.42 to 2.150 ± 0.948 after 3 months of treatment with Tibolone. Only 3 patients (5.6%) experienced vaginal spotting with no major side effects.

Conclusions

Tibolone is a highly effective and well accepted drug to reduce moderate to severe menopausal symptoms, especially psychological symptoms including depression.

Endometrial cancer risk with menopausal hormone therapy: Health Insurance Database in South Korea-based cohort study

OBJECTIVE

To determine the risk of endometrial cancer according to the types of menopausal hormones used.

METHODS

This retrospective cohort study recruited postmenopausal women older than 40 years from 2003 to 2011, utilizing data from the Korean national health insurance system from 2002 to 2019. The menopausal hormone therapy (MHT) group consisted of women who had been prescribed MHT for greater than 6 months between 2003 and 2011. The non-MHT group consisted of women who had never used menopausal hormones between 2003 and 2011.

RESULTS

A non-MHT group of 1 000 550 women and a MHT group of 353 025 women were chosen. In comparison to never-users, the risk of endometrial cancer was not higher in women who reported last using tibolone (adjusted hazard ratio [aHR] 1.08, 95% confidence interval [CI] 0.96-1.2), combined estrogen plus progestin by the manufacturer (aHR 0.83, 0.72-0.96), combined estrogen plus progestin by the physician (aHR 0.88, 0.7-1.12), and transdermal estrogen (aHR 1.13, 0.36-3.52).

CONCLUSIONS

Tibolone, combined estrogen plus progestin by the physician, and transdermal estrogen do not affect the risk of endometrial cancer. The combination of estrogen plus progestin by the manufacturer decreases the risk of endometrial cancer.

[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.

Outcomes of endometrial assessment in women with unscheduled bleeding on hormone replacement therapy

Objective

This study correlates the transvaginal ultrasound findings with histopathology results in women who present with unscheduled bleeding on hormone replacement therapy.

Study design

Retrospective analysis of 469 consecutive cases with unscheduled bleeding on hormone replacement therapy (203 patients on sequential hormone replacement therapy (seq-HRT) and 266 patients on continuous combined hormone replacement therapy (con-HRT)).

Main outcome measures

Outcomes of endometrial assessment in women with unscheduled bleeding on hormone replacement therapy.

Results

Normal appearance of the endometrium on pelvic ultrasound was seen in 62% patients on seq-HRT and 43% of women on con-HRT. These women required no further assessment and were discharged. Histological assessment showed normal endometrial tissue in 22% of women on seq-HRT and 22% of con-HRT group. Benign endometrial polyps were noted in 8% of women on seq-HRT versus 18% of women on con-HRT. Hyperplasia without atypia was noted in 0.5% of woman on seq-HRT versus 0.4% of women on con-HRT while atypical hyperplasia/endometrial cancer was noted in 2% of women on seq-HRT versus 1% of women on con-HRT.

Conclusion

Women who present with unscheduled bleeding on hormone replacement therapy both on sequential and continuous combined regimens can be reassured that the risk of pathology is low.

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.

Hormone therapy in postmenopausal women and risk of endometrial hyperplasia

BACKGROUND

Reduced circulating estrogen levels around the time of the menopause can induce unacceptable symptoms that affect the health and well-being of women. Hormone therapy (both unopposed estrogen and estrogen/progestogen combinations) is an effective treatment for these symptoms, but is associated with risk of harms. Guidelines recommend that hormone therapy be given at the lowest effective dose and treatment should be reviewed regularly. The aim of this review is to identify the minimum dose(s) of progestogen required to be added to estrogen so that the rate of endometrial hyperplasia is not increased compared to placebo.

OBJECTIVES

The objective of this review is to assess which hormone therapy regimens provide effective protection against the development of endometrial hyperplasia or carcinoma.

SEARCH METHODS

We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (searched January 2012), The Cochrane Library (Issue 1, 2012), MEDLINE (1966 to January 2012), EMBASE (1980 to January 2012), Current Contents (1993 to May 2008), Biological Abstracts (1969 to 2008), Social Sciences Index (1980 to May 2008), PsycINFO (1972 to January 2012) and CINAHL (1982 to May 2008). Attempts were made to identify trials from citation lists of reviews and studies retrieved, and drug companies were contacted for unpublished data.

SELECTION CRITERIA

Randomised comparisons of unopposed estrogen therapy, combined continuous estrogen-progestogen therapy, sequential estrogen-progestogen therapy with each other or placebo, administered over a minimum period of 12 months. Incidence of endometrial hyperplasia/carcinoma assessed by a biopsy at the end of treatment was a required outcome. Data on adherence to therapy, rates of additional interventions, and withdrawals owing to adverse events were also extracted.

DATA COLLECTION AND ANALYSIS

In this update, 46 studies were included. Odds ratios (ORs) were calculated for dichotomous outcomes. The small numbers of studies in each comparison and the clinical heterogeneity precluded meta-analysis for many outcomes.

MAIN RESULTS

Unopposed estrogen is associated with increased risk of endometrial hyperplasia at all doses, and durations of therapy between one and three years. For women with a uterus the risk of endometrial hyperplasia with hormone therapy comprising low-dose estrogen continuously combined with a minimum of 1 mg norethisterone acetate (NETA) or 1.5 mg medroxyprogesterone acetate (MPA) is not significantly different from placebo at two years (1 mg NETA: OR 0.04; 95% confidence interval (CI) 0 to 2.8; 1.5 mg MPA: no hyperplasia events).

AUTHORS' CONCLUSIONS

Hormone therapy for postmenopausal women with an intact uterus should comprise both estrogen and progestogen to reduce the risk of endometrial hyperplasia.

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.

Endometrial cancer, types, prognosis, female hormones and antihormones

Endometrial cancer covers several different types, the most prevalent in the developed world being endometrioid adenocarcinoma, which is estrogen-dependent and has a better prognosis compared to the non-estrogen-dependent types, e.g. papillary serous adenocarcinoma and clear cell carcinomas. Prognosis is also dependent on tumor differentiation and stage, and treatment should be adjusted accordingly. In this paper, the different types of endometrial cancer, staging, prognosis, diagnosis, prevention, treatment and their relationship to estrogen and other female hormones are reviewed.

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.

The efficacy and tolerability of short-term low-dose estrogen-only add-back therapy during post-operative GnRH agonist treatment for endometriosis

OBJECTIVE

To evaluate the efficacy and tolerability of a low-dose estrogen-only regimen as a short-term add-back therapy during post-operative GnRH agonist (GnRHa) treatment of patients with endometriosis.

STUDY DESIGN

Retrospective cohort study. One hundred seventeen women of reproductive age who were treated with post-operative GnRHa after conservative laparoscopic surgery for endometrioma were eligible for this study. The patients were divided into two groups: group A (n = 56) received tibolone (2.5mg) between 2002 and 2004 and group B (n = 61) received estradiol valerate (1mg) between 2005 and 2007 as an add-back therapy for five months, beginning at the time of the second injection of a GnRHa. The incidence of hypoestrogenic symptoms and the degree of pelvic pain according to a verbal rating scale (VRS) scoring system, the incidence and patterns of uterine bleeding during add-back therapy, the endometrial thickness by ultrasonography two months after the last GnRHa treatment, and the serum CA-125 level were evaluated.

RESULTS

The incidence of uterine bleeding, hypoestrogenic symptoms such as hot flashes and sweating, and pelvic pain did not differ significantly between the two treatment groups. However, the endometrium was thicker in group A than group B (p = 0.022). In group B, the frequency of uterine bleeding was lower from the second month after starting add-back therapy than in group A, but without statistical significance (at the sixth month, p = 0.086).

CONCLUSION

The low-dose estrogen-only regimen was efficacious and tolerable as a short-term add-back therapy during post-operative GnRHa treatment after surgery for endometriosis.

Long-term postmenopausal hormone therapy and endometrial cancer

Estrogen-alone therapy (ET) or estrogen and progestin (EPT) as menopausal hormone therapy (HT) has been commonly used to alleviate menopausal symptoms. Treatments containing > or = 10 days per month of progestin are considered relatively safe with respect to endometrial cancer risk. However, the endometrial safety of long-term EPT regimens is uncertain. We conducted a case-control study of 311 invasive endometrial cancer cases and 570 controls nested within the California Teachers Study cohort. We used unconditional logistic regression to obtain odds ratios (OR) and 95% confidence intervals (95% CI) for the association between long-term HT use and endometrial cancer risk, and to assess the modifying effect of body mass index (BMI). Long-term (> or = 10 years) use of ET, sequential EPT with <10 days per month progestin, and continuous-combined EPT (> or = 25 days/month progestin) were all associated with an elevated risk of endometrial cancer (OR, 4.5; 95% CI, 2.5-8.1; OR, 4.4; 95% CI, 1.7-11.2; and OR, 2.1; 95% CI, 1.3-3.3, respectively; all P(trend) < 0.001). The risk associated with short-term use was elevated only for ET preparations. The association for continuous-combined EPT was confined to thinner women (BMI, <25 kg/m2; P(interaction) = 0.03). Among heavier women (BMI, > or = 25 kg/m2), use of continuous-combined EPT was associated with a statistically nonsignificant reduction in risk. These findings confirm that long-term use of ET, sequential EPT, or, among normal weight women, continuous-combined EPT is associated with increased risk of endometrial cancer.

Hormone replacement therapy and the endometrium

The life-expectancy for women has increased significantly in the 20th century, although the time of onset of menopause has not. Almost a third of a woman's life is now postmenopausal and therefore many postmenopausal women consider using hormone replacement therapy (HRT) to improve their quality of life. Most cases of endometrial carcinoma arise in postmenopausal women and this raises concern among patients and clinicians with regard to the safety of HRT in this age group. Whenever the use of HRT is considered, a careful consideration of the actual benefit in terms of symptom relief and quality of life must be balanced against the risks for each individual woman. This review discusses the effects of HRT on the endometrium and the evidence regarding HRT use and risk of endometrial cancer.

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.

Endometrial safety and bleeding with HRT: what's new?

There have been few additional published data concerning the effects of hormone replacement therapy (HRT) on the endometrium since December 2003. The Million Women Study has confirmed the known protective effect of progestogen with both sequential and continuous combined regimens, although also reporting an increased risk of endometrial cancer with tibolone. This finding has not been found in any other study previously or in the recently reported OPAL 3-year study. Bleeding during HRT remains an important issue for patient acceptability as well as physician concern about the implications. The incidence of bleeding is related to the dose of estrogen and the development of new low-dose therapies containing 0.5 mg oral estradiol, 0.3 mg oral conjugated equine estrogens or 14 microg estradiol daily by transdermal patch is associated with less bleeding and thus greater patient acceptability as well as minimal endometrial stimulation. Intrauterine delivery of progestogen is the most logical route of administration and provides a high level of progestogen directly to the endometrium, with good endometrial suppression and lower circulating levels than by other routes. The protective effect of progestogen on the endometrium has to be balanced against the apparent adverse effect on breast cancer risk.

Effects of tibolone and its metabolites on Angiopoietin-1, Tie-2 and tumor necrosis factor-alpha mRNA in Ishikawa cells. Implication for tibolone's effects on the endometrium

OBJECTIVE

To determine the effect of 17beta-estradiol, medroxyprogesterone acetate, tibolone and tibolone metabolites on Angiopoietin-1, Tie-2, and tumor necrosis factor-alpha in Ishikawa cells, in vitro. We hypothesized that differential effects on angiogenic factors or inflammatory cytokines by individual hormones may be related to the endometrial bleeding in postmenopausal women using hormone therapy.

DESIGN

Ishikawa cells were cultured to 80% confluence, in vitro. After 24h incubation in serum-free media, 1.0, 0.1 and 0.01 microM of 17beta-estradiol, medroxyprogesterone acetate, tibolone, 3alpha-hydroxytibolone, 3beta-hydroxytibolone, and Delta4-tibolone were added to the Ishikawa cells. The cells plus steroids were then incubated for a further 24h. Total RNA was extracted from control and treated Ishikawa cells. After reverse transcription, Angiopoietin-1, Tie-2, tumor necrosis factor-alpha, and beta-actin cDNAs were amplified in a polymerase chain reaction spiked with 33p-dCTP. Relative abundance of Angiopoietin-1, Tie-2, and tumor necrosis factor-alpha mRNA was measured by scintillation spectroscopy.

RESULTS

17Beta-estradiol and medroxyprogesterone acetate increased Angiopoietin-1 mRNA significantly higher than control, tibolone and tibolone hydroxy metabolites. Delta4-Tibolone at all concentrations tested did not increase Angiopoietin-1. None of the steroids tested at any concentration altered Tie-2 mRNA expression compared to control. 17Beta-Estradiol at 1.0 and 0.1 microM increased tumor necrosis factor-alpha mRNA significantly higher than control. Medroxyprogesterone acetate only at 1.0 microM increased tumor necrosis factor-alpha mRNA above control levels. Tibolone, 3alpha-hydroxytibolone, 3beta-hydroxytibolone, and Delta4-tibolone at every concentration had no effect on tumor necrosis factor-alpha mRNA abundance.

CONCLUSIONS

Delta4-Tibolone did not stimulate Angiopoietin-1, while the other steroids had differential effects greater than control. None of the steroids changed the expression of Tie-2 mRNA. Tumor necrosis factor-alpha was increased by 17beta-estradiol and by the highest concentration of medroxyprogesterone acetate. We interpret these results as supportive of our hypothesis that differential effects on angiogenic factors or inflammatory cytokines by individual steroids may be related to the clinical occurrence of endometrial bleeding in postmenopausal women using hormone therapy.