Bleeding pattern and endometrial changes during continuous combined hormone replacement therapy. The Ogen/Provera Study Group

Danshen enhanced the estrogenic effects of Qing E formula in ovariectomized rats

BACKGROUND

Menopause is characterized by a decrease in life quality due to the appearance of uncomfortable symptoms. Nowadays, Understanding menopause-associated pathophysiology and developing new strategies to improve the treatment of menopausal-associated symptoms is an important issue. Our study was to evaluate the synergistic effects of Danshen (salvia miltiorrhiza bunge) and the phytoestrogenic effects of 3 modified Qing E formulas, to explore a better formula for menopausal disorders.

METHODS

100 rats were randomized into 5 groups: Sham (Sham operation group), OVX (model group of ovariectomized rat), BDL (group with low concentration of Qing E Formula), BDH (group with high concentration of Qing E Formula) and BDD (group with high concentration of Qing E Formula Plus Danshen), receiving vehicle and extract of different modified Qing E formula respectively. The food intake, body weight, uterus weight, blood levels of triglycerides (TG), total cholesterol (TC) and cholesterol fractions were assessed. The mammary glands and uterus were morphologically analyzed. The bone density of tibias were measured by peripheral quantitative computed tomography (pQCT). Additionally, luciferase induction assays were performed in Hela cells with the mixtures derived from Qing E formula plus Danshen (BDD).

RESULTS

Qing E formula plus Danshen significantly increased the uterus wet weight, enhanced the thickness of uterine wall, endometrial epithelium and glandular epithelium, improved trabecular bone and total density evidently, reduced the levels of low density lipoprotein cholesterol (LDL-C) and TG, possessed notable estrogen receptor beta (ERβ) and estrogen receptor alpha (ERα) agonist activity.

CONCLUSION

Qing E formula plus Danshen exerted more evident estrogen-like effects, thus it has a potential therapeutic use to treat menopausal disorders.

Cyclopia extracts act as ERα antagonists and ERβ agonists, in vitro and in vivo

Hormone replacement therapy associated risks, and the concomitant reluctance of usage, has instigated the search for new generations of estrogen analogues that would maintain estrogen benefits without associated risks. Furthermore, if these analogues display chemo-preventative properties in breast and endometrial tissues it would be of great value. Both the selective estrogen receptor modulators as well as the selective estrogen receptor subtype modulators have been proposed as estrogen analogues with improved risk profiles. Phytoestrogen containing extracts of Cyclopia, an indigenous South African fynbos plant used to prepare Honeybush tea may serve as a source of new estrogen analogues. In this study three extracts, P104, SM6Met, and cup-of-tea, from two species of Cyclopia, C. genistoides and C. subternata, were evaluated for ER subtype specific agonism and antagonism both in transactivation and transrepression. For transactivation, the Cyclopia extracts displayed ERα antagonism and ERβ agonism when ER subtypes were expressed separately, however, when co-expressed only agonism was uniformly observed. In contrast, for transrepression, this uniform behavior was lost, with some extracts (P104) displaying uniform agonism, while others (SM6Met) displayed antagonism when subtypes were expressed separately and agonism when co-expressed. In addition, breast cancer cell proliferation assays indicate that extracts antagonize cell proliferation in the presence of estrogen at lower concentrations than that required for proliferation. Furthermore, lack of uterine growth and delayed vaginal opening in an immature rat uterotrophic model validates the ERα antagonism of extracts observed in vitro and supports the potential of the Cyclopia extracts as a source of estrogen analogues with a reduced risk profile.

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.

Hormone therapy in postmenopausal women and risk of endometrial hyperplasia

BACKGROUND

Declining 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 and/or carcinoma.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (searched January 2008), The Cochrane Library (Issue 1, 2008), MEDLINE (1966 to May 2008), EMBASE (1980 to May 2008), Current Contents (1993 to May 2008), Biological Abstracts (1969 to 2008), Social Sciences Index (1980 to May 2008), PsycINFO (1972 to May 2008) 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 and/or sequential estrogen-progestogen therapy with each other or placebo, administered over a minimum period of twelve 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 due to adverse events were also extracted.

DATA COLLECTION AND ANALYSIS

In this substantive update, forty five studies were included. Odds ratios 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 or 1.5 mg medroxyprogesterone acetate is not significantly different from placebo (1mg NETA: OR=0.04 (0 to 2.8); 1.5mg 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.

Comparing raloxifene with continuous combined estrogen-progestin therapy in postmenopausal women: Review of Euralox 1

OBJECTIVES

To review the main findings of the Euralox 1 study - a multicentre, randomised, double-blind study conducted in 1008 healthy postmenopausal women allocated to raloxifene (n = 495) or continuous combined estrogen-progestin therapy (ccEPT; n = 513) for 6 months -- and provide an overview of the risks and benefits of raloxifene and ccEPT.

METHODS

A review is provided of previously published findings on uterine safety (bleeding rates and changes in endometrial thickness and uterine volume), gynaecological adjudication, cardiovascular risk (lipids, fibrinogen), adverse events, compliance, treatment satisfaction and quality of life. New data on biochemical markers of bone turnover (serum N-telopeptides and C-terminal telopeptides of type I collagen; NTX and CTX) assessed before and after 6 months' treatment are presented.

RESULTS

Raloxifene caused less uterine bleeding than ccEPT and, unlike ccEPT, did not alter endometrial thickness or uterine volume. Serum CTX and NTX levels were reduced in both treatment groups, but the reduction was significantly greater with ccEPT. The two treatments had differential effects on lipids and fibrinogen levels; raloxifene had more favourable effects on serum HDL, the LDL/HDL ratio, and plasma fibrinogen. Raloxifene was associated with fewer adverse events or discontinuations, and this was associated with higher treatment satisfaction and better self-reported compliance.

CONCLUSIONS

The clinical risk-benefit profile of raloxifene derived from the intermediate endpoints of this study suggests that it may be a better alternative to ccEPT for preventing long-term postmenopausal health risks in healthy postmenopausal women who are not suffering from vasomotor symptoms.

Hormone replacement therapy (HRT) and endometrial morphology under consideration of the different molecular pathways in endometrial carcinogenesis

The majority of modern hormone replacement therapy (HRT) regimens contain estrogen and progestogens, given either in a cyclical or continuous manner. About 15% of the endometrial biopsies taken from women on sequential HRT show proliferative activity including atypical endometrial hyperplasia in up to 1% of the cases. The majority of biopsies from women under continuous combined HRT show an endometrial atrophy. About 2-3% of these women will present proliferative activity, usually without atypical hyperplasia. Contrary to breast cancer, an increased risk of endometrial cancer has not been reported in the WHI- and HERS-studies. However, endogenous factors, such as obesity, diabetes mellitus, the distribution of estrogen receptors alpha and beta and genetic polymorphisms for receptors and enzymes might alter the endometrial stimulation under different types of HRT. There should be a liberal indication for endometrial biopsies in Hereditary Non-Polyposis Colorectal Cancer (HNPCC). HNPCC-patients under HRT as well as for ultrasonographic evaluation of the endometrium. The risk of atypical hyperplasias or carcinoma under unopposed estrogen-therapy varies from 2 to 10%. So, this kind of HRT should not be used in non-hysterectomised women. As far as the risk of endometrial cancer under any kind of HRT is concerned, the different molecular pathways of endometrial carcinogenesis (type 1 and 2 cancers) should be taken into account. The use of tibolone leaves the endometrium unaffected.

Vaginal rings delivering progesterone and estradiol may be a new method of hormone replacement therapy

OBJECTIVE

To determine whether a low dose of P delivered together with E(2) from a vaginal ring on a continuous schedule can prevent endometrial proliferation and yield a bleeding pattern dominated by amenorrhea.

DESIGN

Longitudinal clinical study.

SETTING

Three university hospitals.

PATIENT(S)

Fifty-five women 45 to 75 years of age, not hysterectomized, with E(2) levels of <20 pg/mL and hot-flash incidence of two or more per day in the past week.

INTERVENTION(S)

A vaginal ring delivering approximately 150 microg/d of 17beta-E(2) and approximately 5 mg/d or approximately 9 mg/d of P used continuously for 4 and 6 months.

MAIN OUTCOME MEASURE(S)

Endometrial thickness, bleeding pattern, and hot flash incidence.

RESULT(S)

Endometrial proliferation was prevented by both P doses. Bleeding incidence decreased. In months 4, 5, and 6, 8 of 12 women had no bleeding. Incidence of hot flashes and night sweats decreased quickly and significantly.

CONCLUSION(S)

A vaginal ring delivering E(2) and a low dose of P merits further study as a method for long-term hormone replacement therapy.

Effect on endometrium of long term treatment with continuous combined oestrogen-progestogen replacement therapy: follow up study

OBJECTIVE

To determine effects of five years of treatment with an oral continuous combined regimen of 2 mg 17beta-oestradiol and 1 mg norethisterone acetate on endometrial histology in postmenopausal women.

DESIGN

Follow up study in postmenopausal women.

SETTING

31 menopause clinics in the United Kingdom.

PARTICIPANTS

534 postmenopausal women, all with an intact uterus, who had completed nine months of treatment with oral continuous combined 2 mg 17beta-oestradiol and 1 mg norethisterone acetate agreed to take part in a long term follow up study. Women were assigned to different groups on the basis of the treatment status immediately before entering the original study: 360 women had taken sequential oestrogen-progestogen hormone replacement therapy, 164 had taken no hormone replacement therapy, and 10 had taken unopposed oestrogen therapy.

METHODS

Endometrial aspiration specimens were taken before the women started the continuous combined regimen, after 9 and 24-36 months, and at the end of the five year treatment period or on withdrawal from the study.

MAIN OUTCOME MEASURE

Results of endometrial histology.

RESULTS

The duration of treatment with continuous combined hormone replacement therapy was 4.4 (range 1.1-5.9) years. Data on endometrial specimens were available for 526 women after nine months of treatment, 465 women after 24-36 months of treatment, and 398 women who completed the five years treatment (345 women) or were withdrawn between the two latter visits for biopsies (53 women). No cases of endometrial hyperplasia or malignancy were detected at biopsy; 69% of women had an endometrium classified as atrophic or unassessable on completion of the study or withdrawal from it. Before the continuous combined therapy was started, complex hyperplasia was detected in 21 women who had taken sequential hormone replacement therapy before the study and in one who had taken unopposed oestrogen. All of these women had normal results on histological examination of endometrial tissue after nine months of treatment with continuous combined hormone replacement therapy, and hyperplasia did not recur after up to five years of treatment.

CONCLUSIONS

Long term treatment (for up to five years) with continuous combined hormone replacement therapy containing oestradiol 2 mg and norethisterone 1 mg daily was associated with neither endometrial hyperplasia nor malignancy. In women who had complex hyperplasia during previous sequential or unopposed regimens, the endometrium returned to normal during treatment with continuous combined hormone replacement therapy. These findings provide reassurance about the long term safety of this continuous combined regimen in terms of the endometrium.

Medroxyprogesterone acetate does not antagonize estrogen-induced increases in endothelium-dependent vasodilation: potential clinical implications

OBJECTIVE

Determine the effect of combined 17beta-estradiol benzoate (E2) and medroxyprogesterone acetate (MPA) administration on endothelium-dependent vasorelaxation to acetylcholine (ACh).

DESIGN

Prospective, ex vivo study.

SETTING

Academic research laboratory.

ANIMAL(S)

Mature female rats.

INTERVENTION(S)

Ovariectomized rats received one of the following interventions daily for 3 days: [1] corn oil via IM injection, [2] E2 (20 microg/kg IM), or [3] E2 (20 microg/kg IM) and MPA (10 mg/kg IM).

MAIN OUTCOME MEASURE(S)

Basal release of nitric oxide (NO) and endothelium-dependent and endothelium-independent vasodilation from thoracic aortas obtained from each group.

RESULT(S)

Estradiol treatment potentiated the endothelium-dependent relaxation to ACh when compared with the control group. Administration of MPA with E2 did not antagonize the beneficial effect of E2 on endothelium-dependent relaxation. Estradiol treatment alone or in combination with MPA did not affect endothelium-independent vasodilation as compared with the case of the control group. Administration of E2 resulted in increased basal NO release (assessed indirectly by measuring the constrictor response to N(G)-nitro-L-arginine [methyl ester (L-NAME)]) when compared with the case of the control group, and the addition of MPA to E2 did not alter the effect of E2 on basal NO release.

CONCLUSION(S)

Estradiol potentiates endothelium-dependent relaxant responses and increases basal endothelial NO release. Medroxyprogesterone acetate does not antagonize these effects of E2.

Hormone replacement therapy and the endometrium

Modern hormone replacement therapy (HRT) regimens contain oestrogen and progestogen, given either in a cyclical or continuous combined manner. Most endometrial biopsies from women on sequential HRT show weak secretory features. Approximately 15% show proliferative activity, although this figure may be less if more than nine days of progestogen is given in each cycle. A small proportion will show an inactive or atrophic endometrium. Up to 50% of biopsies from women on continuous combined HRT contain minimal endometrial tissue for histopathological analysis: this correlates well with an atrophic endometrium with no appreciable pathology. Of the 50% with more substantial material, approximately one half will show endometrial atrophy, and one half will show weak secretory features. Proliferative, menstrual, and pseudodecidual changes are rare. Approximately 20% of women given unopposed oestrogen for one year develop endometrial hyperplasia. The relative risk of endometrial carcinoma is two to three. This is dramatically reduced by the addition of progestogen to the regimen, but cyclical progestogen as part of a sequential HRT regimen does not completely eliminate the risk of carcinoma. The prevalence of endometrial hyperplasia associated with sequential HRT is 5.4%, and that of atypical hyperplasia (endometrial intraepithelial neoplasia) is 0.7%. Continuous combined HRT is not associated with the development of hyperplasia or carcinoma, and may normalise the endometrium of women who have developed complex hyperplasia on sequential HRT. The probability of a histopathologist finding clinically relevant pathology in an endometrial biopsy specimen of a patient on HRT is low and is more likely to be a manifestation of pre-existing disease.

The endometrial response to sequential and continuous combined oestrogen-progestogen replacement therapy

OBJECTIVES

1. To determine the prevalence of endometrial hyperplasia in postmenopausal women taking standard proprietary regimens of sequential oestrogen/progestogen; 2. to determine the effects of nine months treatment with an oral continuous combined regimen of 2 mg 17beta-oestradiol and 1 mg norethisterone acetate (Kliofem [Kliogest outside the UK]; Novo Nordisk, Denmark) on endometrial histology in postmenopausal women.

DESIGN

An open, prospective study in postmenopausal women.

SETTING

Fifty-four menopause clinics in the UK.

PARTICIPANTS

2028 postmenopausal women: 1312 (Group A) taking sequential oestrogen-progestogen hormone replacement therapy (HRT), and 716 (Group B) not taking HRT, were recruited. In Group A, 388 women took preparations containing 10 days of progestogen, 921 had 12 days, and 3 had 13 days per cycle.

METHODS

Endometrial aspiration biopsies were taken towards the end of a three-month run-in period (Group A) or at study entry (Group B), before administration of the continuous combined HRT regimen. Biopsies were repeated at the end of the nine month treatment period.

MAIN OUTCOME MEASURE

Endometrial histology.

RESULTS

Initial endometrial biopsy data were available for 1106 women in Group A, who by the time of endometrial investigation had been taking HRT for a median duration of 2.56 years (5th to 95th centiles: 0.77 to 8.49 years). Data were available for 661 untreated women, who had no bleeding and had not taken HRT within the last year (Group B). Complex hyperplasia was found in 59 women (5.3%), and atypical hyperplasia in a further eight (0.7%) in Group A. In Group B there were no cases with complex hyperplasia, but one woman showed atypical hyperplasia (0.2%). At the end of the nine months of continuous combined therapy there was no case of hyperplasia among 1196 biopsies (upper 95% confidence limit of risk 0.31%) in women completing the study. Within this Group all of the women with complex hyperplasia arising during previous sequential HRT and who completed the study (n = 38) reverted to normal endometrial patterns. There was no case of endometrial carcinoma during the study.

CONCLUSIONS

Despite taking standard regimens of sequential HRT containing at least 10 days of progestogen, there was a 5.3% prevalence of complex endometrial hyperplasia, and a 0.7% prevalence of atypical hyperplasia. However, continuous combined HRT (Kliofem) containing daily progestogen is not associated with an increased risk of hyperplasia and will convert the endometrium to normal in those with complex hyperplasia arising during previous sequential HRT.

Hormonal replacement regimens and bleeding

Hormone replacement therapy may increase the quality of life of postmenopausal women. Any regimen need to offer long-term endometrial safety. It is a standard to consider the co-administration of a sequential progestogen when estrogen replacement should be initiated in non-hysterectomized women. It is almost impossible to decide which combination of an estrogen and a progestogen seems to be optimal as individual tolerance of HRT may very well limit acceptability despite metabolic benefits and proven endometrial safety of a given combination. Several combinations of oral and transdermal estradiol or conjugated equine estrogens, oral progestogens, transdermal norethisterone acetate and levonorgestrel, and intrauterine levonorgestrel may achieve endometrial safety. It is noteworthy that there is no uniform correlation between the timing of onset of bleeding induced by any sequential estrogen and progestogen replacement and a certain pattern of histology. Therefore, although it is likely, there is no absolute reassurance that regular bleeding on or after day 11 of progestogen administration rules out abnormal histopathology. Transvaginal sonography seems not to be of pivotal importance to screen asymptomatic women on replacement therapy for detection of serious abnormal endometrial findings such as hyperplasia and endometrial cancer. Continuous combined hormone replacement therapy or the use of tibolone may be an alternative in postmenopausal women, who do not want any uterine bleedings after menopause. However, spottings or bleedings most often occur at the beginning of treatment. Vaginal administration of estriol and estradiol for urogenital symptoms of estrogen deficiency may stimulate the endometrium unintentionally. Available data suggest that use of oral estriol may be associated with endometrial hyperplasia and endometrial carcinoma relatively more often compared to sequential HRT. Raloxifene, a benzothiophene derivative acting as a selective estrogen receptor modulator approved for prevention of vertebral osteoporosis, rarely causes uterine bleeding. There is no ideal therapy available to suit women looking for a permanently bleed-free hormonal replacement therapy today.

Menopausal symptom control and side-effects on continuous estrone sulfate and three doses of medroxyprogesterone acetate. Ogen/Provera Study Group

OBJECTIVES

To establish the optimum oral daily dose of micronized medroxyprogesterone acetate (MPA), given in combination with 1.25 mg of estrone sulfate for menopausal symptom control.

METHODS

This multicenter, randomized, double-blind study was conducted on 568 postmenopausal women who were randomized to take estrone sulfate 1.25 mg daily with 2.5, 5.0 or 10 mg of MPA daily for 2 years. The number of vasomotor symptoms and the severity of mood swings, lethargy, vaginal dryness and loss of libido as well as side-effects were recorded in a diary. Blood pressure and weight were recorded at each 3-month visit.

RESULTS

Vasomotor symptoms were reported by approximately 80% of subjects at month 1, 23% at month 3 but only 9% by month 24. Mood swings, lethargy and vaginal dryness improved rapidly in the initial 3 months of therapy. Decrease in libido had a slower response to therapy in all three treatment groups. Breast tenderness was the commonest side-effect with 22% of subjects complaining of this in the first 3 months of therapy, dropping to 13% by 6 months. Headache, depression, nausea, bloating and irritability showed a similar pattern of decline. There was no significant difference in the rate of decrease in menopausal symptoms or reported side-effects between the three treatment groups. There was a small but significant (p < 0.001) decrease in systolic and diastolic blood pressure over the study period.

CONCLUSIONS

All three treatment regimens provide adequate symptom control. Side-effects decreased markedly after the first 3 months, with no significant difference between the treatment groups.