Changes in plasma lipoprotein and apolipoprotein composition in relation to oral versus percutaneous administration of estrogen alone or in cyclic association with utrogestan in menopausal women

Reappraising 21 years of the WHI study: Putting the findings in context for clinical practice

Menopausal hormone treatment (MHT) is recommended for the management of menopause symptoms. The Women's Health Initiative (WHI) placebo-controlled randomised study examined the effects of continuous combined or estrogen-only MHT on the risk of non-communicable diseases (NCDs) in post-menopausal women. The study was terminated prematurely after an interim analysis showed an increased risk of breast cancer diagnosis, which led to a rapid decrease in MHT use worldwide. Subsequently, limitations of the study design and its interpretation in the context of other clinical studies has contributed to a more nuanced appreciation of the risk-benefit profile of differing MHT regimens regarding risk associated with the class of progestogen prescribed, its pattern of prescription, duration of use and timing of initiation related to menopause onset. This review provides a contextual interpretation of the WHI placebo-controlled study and evaluates the impact of bioidentical MHT, with a focus on combined therapies containing micronised progesterone, on the risk of chronic NCDs in post-menopausal women.

Hormone Replacement Therapy after Pubertal Induction in Adolescents and Young Adults with Turner Syndrome: A Survey Study

INTRODUCTION

Turner syndrome (TS) is associated with primary ovarian insufficiency (POI) and most adolescents and young adults (AYA) with TS require treatment with hormone replacement therapy (HRT). International consensus guidelines are unclear on the optimal formulation and dosing for HRT after pubertal induction. This study assessed current HRT practice patterns of endocrinologists and gynecologists in North America.

METHODS

Email listserv members of the North American Society for Pediatric and Adolescent Gynecology (NASPAG) and the Pediatric Endocrine Society (PES) were invited to complete a 19-question survey to assess HRT treatment preferences for the management of POI after completion of pubertal induction in AYA with TS. Descriptive analysis and multinomial logistic regression to predict factors associated with preferred HRT are presented.

RESULTS

155 providers (79% pediatric endocrinology, 17% pediatric gynecology) completed the survey. Although 87% (135) reported confidence in prescribing HRT, only half (51%, 79) were aware of published guidelines. Factors significantly associated with preferred HRT included specialty (p = 0.032) and number of patients with TS seen every 3 months (p = 0.024). Gynecologists were 4 times less likely than endocrinologists to prefer hormonal contraceptives and 4 times more likely to favor transdermal estradiol dose of 100 μg/day as compared to lower doses.

CONCLUSION

Although most endocrinologists and gynecologists report confidence in prescribing HRT to AYA with TS after pubertal induction, there are clear differences in provider preferences based on specialty and higher volume of patients with TS in their practice. Additional studies on comparative effectiveness of the HRT regimens and evidence-based guidelines are necessary for AYA with TS.

Androgen therapy for women after menopause

Androgens are essential hormones in women. Yet, androgen therapy is understudied and underutilized despite showing improvement in postmenopausal hypoactive sexual desire disorder (HSDD) and the genitourinary syndrome of menopause (GSM). Additionally, regulatory concerns have left a significant gap in commercially available testosterone preparations, formulated specifically for women, in most countries. This has led to off-label use of male formulations and compounded therapies which are under-regulated. Beyond HSDD and GSM, testosterone likely influences the brain, breast, cardiovascular and musculoskeletal systems. These effects are not well studied, and therefore it is difficult to counsel patients on testosterone therapy when used for these endpoints. Ultimately, further study is needed to elucidate these effects, create a fuller picture of the risks and benefits, and encourage product development specifically designed for women.

Management of hypertriglyceridemia

Hypertriglyceridemia is one of the most common lipid abnormalities encountered in clinical practice. Many monogenic disorders causing severe hypertriglyceridemia have been identified, but in most patients triglyceride elevations result from a combination of multiple genetic variations with small effects and environmental factors. Common secondary causes include obesity, uncontrolled diabetes, alcohol misuse, and various commonly used drugs. Correcting these factors and optimizing lifestyle choices, including dietary modification, is important before starting drug treatment. The goal of drug treatment is to reduce the risk of pancreatitis in patients with severe hypertriglyceridemia and cardiovascular disease in those with moderate hypertriglyceridemia. This review discusses the various genetic and acquired causes of hypertriglyceridemia, as well as current management strategies. Evidence supporting the different drug and non-drug approaches to treating hypertriglyceridemia is examined, and an easy to adopt step-by-step management strategy is presented.

Evidence on the use of progesterone in menopausal hormone therapy

A need exists for a regulatory agency-approved hormone therapy (HT) with naturally occurring hormones combining progesterone (P4) and estradiol (E2), since no single product contains both endogenous hormones. Many women choose HT with P4 and millions of women around the world are using unapproved, poorly regulated compounded HT. The use of natural P4 in HT results, for the most part, in favorable outcomes without deleterious effects, as shown in clinical studies of postmenopausal women. Importantly, P4 used in HT prevents endometrial hyperplasia from estrogens while helping relieve vasomotor symptoms and improving quality-of-life measures. Additionally, risk of venous thromboembolism and breast cancer does not appear to increase with use of P4 plus estrogens as shown with synthetic progestins plus estrogens in large observations studies, and no detrimental effects of P4 in HT have been found on outcomes related to cardiovascular disease or cognition. A regulatory agency-approved HT with naturally occurring E2/P4 could be an option for the millions of women who desire a bioidentical product and/or are exposed to potential risks of inadequately studied and under-regulated compounded HT.

Benefits and risks during HRT: main safety issue breast cancer

To assess the benefits and risks during hormone replacement therapy (HRT) in postmenopausal women, the only placebo-controlled study testing clinical endpoints with high statistical power has been the Women's Health Initiative (WHI). Although this trial, conducted mainly in older high-risk women, might not reflect the practical conditions for the normal use of HRT, the WHI for the first time provides the main risks in relative as well as in absolute numbers, which are venous thromboembolism and breast cancer, and in older women also myocardial infarction and stroke. Proven benefits such as treatment of climacteric symptoms, reduction of osteoporotic fractures and decrease of colon cancer risk seem to be only important for younger women, because only with early start of HRT cardiovascular risks can be reduced. Reduction of cardiovascular risks can be achieved using transdermal HRT, which, however, was not tested in a placebo-controlled study design similar to that in the WHI. This review focuses on the results of the WHI, comparing different age groups, and in general especially on the main fear of women, risk of breast cancer, which has been defined as a special project between two universities, a close collaboration of a German and Chinese research group.

Menopausa e síndrome metabólica

A incidência de doença cardiovascular aumenta consideravelmente após a menopausa. Um dos motivos para o crescente risco cardiovascular parece ser determinado pela síndrome metabólica, da qual todos os componentes (obesidade visceral, dislipidemia, hipertensão arterial e distúrbio do metabolismo glicídico) se associam à maior incidência de coronariopatia. Após a menopausa, a síndrome metabólica é mais prevalente do que na pré-menopausa, podendo ter importante papel na ocorrência de infarto do miocárdio e outras morbidades ateroscleróticas e cardiovasculares. A obesidade, componente primordial da síndrome metabólica, se associa ainda ao aumento da incidência de câncer de mama, endométrio, intestino, esôfago e rim. O tratamento da síndrome metabólica se baseia na mudança de hábitos de vida e, quando necessário, no emprego de medicação dirigida aos seus componentes. Na presença de sintomas de síndrome do climatério, a terapia hormonal, quando indicada, concorrerá também para a melhora da síndrome metabólica.

Hormone-replacement therapy, dementia and stroke

Hormone-replacement therapy (HRT) has been used for more than 40 years to reduce perimenopausal symptoms. Estrogens may protect brain structures and functional systems affected by Alzheimer's disease, which suggests that maintaining high levels of hormones with HRT can protect against Alzheimer's disease. Moreover, high premenopausal estrogen concentrations are thought to be protective against stroke and, consequently, in the past, HRT was considered to be a potential protective agent against stroke. However, large clinical trials have failed to demonstrate a benefit from HRT on either cognitive performance or risk of dementia. In addition, although HRT has been associated with a reduction in the risk of heart disease in observational studies, results regarding stroke have been less clear. Recently, evidence has shown that HRT does not reduce but actually increases vascular risk. Here, the data from the most important studies are examined, concluding that HRT has no beneficial effect on dementia or stroke risk reduction in postmenopausal women.

Hormone replacement therapy in the geriatric patient: current state of the evidence and questions for the future. Estrogen, progesterone, testosterone, and thyroid hormone augmentation in geriatric clinical practice: part 1

This article presents an up-to-date review of the literature on hormone augmentation in the elderly to help primary care physicians better evaluate and utilize hormone replacement and optimization strategies to benefit their patients. The scientific literature suggests that hormone supplementation with estrogen, progesterone, testosterone, growth hormone, and thyroid hormone has the potential to improve quality of life and to prevent, or reverse, the many symptoms and conditions associated with aging, including fatigue, depression, weight gain,frailty, osteoporosis, loss of libido, and heart disease. Possible long-term side effects are also considered.

Hormonal replacement therapy (HRT) in postmenopause: a reappraisal

Hormone replacement therapy (HRT) is the most effective treatment currently available for vasomotor and urogenital symptoms and decreased libido. Because harmful effects were evidenced in some clinical trials, health authorities now consider that risk-benefit considerations do not favour the use of HRT for prevention of cardiovascular diseases and bone fractures in postmenopausal women. However, experimental and clinical studies indicate that adverse effects of HRT may largely depend on the estrogen and progesterone/progestin formulation, dosage, mode of administration, patient's age, associated diseases, and duration of treatment. All estrogen formulations and modes of administration have similar beneficial effects on vasomotor and urogenital symptoms and on bone structure. But cardiovascular and invasive breast cancer risks are higher with oral estrogen than with transdermal estradiol, and also higher with many progestin compounds than with micronized progesterone. The combination of transdermal estradiol+micronized progesterone appears to be effective and relatively safe if elementary precautions are taken, and seems to be presently the best choice for HRT in most postmenopausal women. In the author's--heterodox--opinion, HRT may also be a good therapeutic choice to prevent bone loss, since alternative medications, including raloxifene and bisphosphonates, may have dramatic harmful effects in some patients. It might also have beneficial effects on the development of coronary disease in young postmenopausal women. HRT requires careful adjustment to each individual patient and continuous monitoring of clinical evolution. In the future, this adjustment could benefit from genetic screening to maximize in each individual the ratio between positive and adverse effects.

A Review of Drospirenone for Safety and Tolerability and Effects on Endometrial Safety and Lipid Parameters Contrasted with Medroxyprogesterone Acetate, Levonorgestrel, and Micronized Progesterone

BACKGROUND

Drospirenone, a novel synthetic progestin, possesses characteristics more like natural progesterone than other synthetic progestins, such as medroxyprogesterone acetate and levonorgestrel. The antiandrogenic and antimineralocorticoid properties of drospirenone may, in the context of menopausal management, provide potential novel benefits in its effect on lipids and blood pressure while reducing the occurrence of water retention, acne vulgaris, and hirsutism.

METHODS

This review compares safety and tolerability data from clinical trials of drospirenone, medroxyprogesterone acetate, levonorgestrel, and micronized progesterone.

RESULTS

Results suggest that drospirenone possesses a generally well-accepted side effect profile and resembles comparator oral progestogens in conferring endometrial protection with no significant effect on weight. One study indicates that drospirenone may have a benign effect on lipid parameters, having been seen to significantly lower total cholesterol and lowdensity lipoprotein levels while maintaining high-density lipoprotein and triglyceride levels. Drospirenone also differs from the other progestogens in lowering blood pressure levels in hypertensive patients while having a mild blood pressure-lowering effect on nonhypertensive patients.

CONCLUSIONS

Among pharmacological options for menopause management, drospirenone may provide certain advantages over other progestogens in its effect on risk factors for cardiovascular disease and, thus, constitutes a useful addition to the menopausal armamentarium.

New evidence regarding hormone replacement therapies is urgently required

Controversies about the safety of different postmenopausal hormone therapies (HTs) started 30 years ago and reached a peak in 2003 after the publication of the results from the Women Health Initiative (WHI) trial and the Million Women Study (MWS) [Writing group for the women's health initiative investigations. Risks and benefits of estrogen plus progestin in healthy postmenopausal women. JAMA 2002;288:321-33; Million women study collaborators. Breast cancer and hormone-replacement therapy in the million women study. Lancet 2003;362:419-27]. The single HT formulation used in the WHI trial for non hysterectomized women-an association of oral conjugated equine estrogens (CEE-0.625 mg/day) and a synthetic progestin, medroxyprogesterone acetate (MPA-2.5 mg/day)-increases the risks of venous thromboembolism, cardiovascular disease, stroke and breast cancer. The MWS, an observational study, showed an increased breast cancer risk in users of estrogens combined with either medroxyprogesterone acetate (MPA), norethisterone, or norgestrel. It is unclear and questionable to what extent these results might be extrapolated to other HRT regimens, that differ in their doses, compositions and administration routes, and that were not assessed in the WHI trial and the MWS. Significant results were achieved with the publication of the WHI estrogen-only arm study [Anderson GL, Limacher M, Assaf AR, et al. Effects of conjugated equine estrogen in postmenopausal women with hysterectomy: the Women's Health Initiative randomized controlled trial. JAMA 2004;291:1701-1712] in which hormone therapy was reserved to women who had carried out hysterectomy. What emerged from this study will allow us to have some important argument to develop.

Effect of micronized progesterone on bone turnover in postmenopausal women on estrogen replacement therapy

PURPOSE

To determine whether daily oral micronized progesterone affects bone turnover, as estimated by serum and urine biochemical markers, in postmenopausal women on long-term estrogen replacement therapy (ERT).

METHODS

We recruited 14 women aged 65 or older to participate in a 9-week trial with micronized progesterone. Each woman had undergone a hysterectomy and was on unopposed ERT at time of study entry. Women received micronized progesterone 100 mg twice daily in the first week and then received 200 mg twice daily in weeks 2-9. We measured markers of bone turnover in serum and urine collected at baseline and at 3 weeks, 6 weeks, and 9 weeks on treatment. Markers of bone formation were serum bone alkaline phosphatase (BAP), N-terminal procollagen peptides (PINP), and osteocalcin (OC). Markers of bone resorption were urinary cross-linked N-terminal and C-terminal telopeptides of type I collagen. In addition, we measured serum progesterone, estradiol and sex hormone binding globulin, triglycerides, total cholesterol, and high-density lipoprotein (HDL)-cholesterol levels at baseline and at 9 weeks on treatment.

RESULTS

Mean serum progesterone levels increased from 1.6 +/- 1.1 to 15.2 +/- 3.9 ng/mL, which was within the luteal phase range (3-25 ng/mL). Crosslinked C-telopeptides of type I collagen and osteocalcin increased significantly (p < 0.05) with progesterone treatment, however, other bone markers did not change. Estradiol, estrone, and SHBG levels did not change with treatment. High-density lipoprotein-cholesterol levels decreased 19% (p < 0.001) at 9 weeks on treatment compared to baseline but total and low-density lipoprotein (LDL) cholesterol and triglycerides did not change with treatment.

CONCLUSION

In postmenopausal women on long-term estrogen replacement therapy, micronized progesterone (400 mg/d) increased one marker each of bone resorption and bone formation. Other sensitive markers of bone turnover did not change with treatment. Further, micronized progesterone decreased HDL-cholesterol in these women. Our data do not support a beneficial effect of micronized progesterone on bone or cardiovascular risk factors in postmenopausal women.

Effects of estradiol and estradiol sulfamate on the liver of ovariectomized or ovariectomized and hypophysectomized rats

This study was performed to evaluate and compare the effects of estradiol sulfamate (J995) and estradiol (E2) on the hepatic levels of the estrogen receptor (ER) and its mRNA, in ovariectomized (OVX) and OVX+hypophysectomized (OVXHX) female rats and to study the effects on the liver-derived serum compounds angiotensin I, triglycerides, high-density lipoprotein (HDL) and cholesterol. ER concentrations were determined using ligand-binding assay (LBA) and enzyme immuno assay (EIA), and the mRNA levels using solution hybridization. The rats were treated orally (p.o.) or subcutaneously (s.c.) for 7 days, with treatments initiated 14 days after surgery. No differences were found in ER mRNA levels between J995 and E2 treated rats. The s.c. administered estrogens increased ER levels in OVX rats. Addition of GH+DEX to OVXHX rats restored the ER to levels above those seen in intact rats, whereas simultaneous oral treatment with E2 significantly decreased ER levels again. The s.c. treatment with either J995 or E2 limited the increase caused by addition of GH+DEX. After oral treatment angiotensin I levels were increased by E2, but not by J995, while triglycerides, HDL and cholesterol levels were decreased by oral E2, J995 showing a similar pattern but was less effective. In summary, these results on hepatic ER levels and estrogen dependent compounds produced by the liver showed that J995 has a lower impact on the normal liver functions after oral treatment than E2. Thus, J995 is a very promising substance for development of oral estrogen treatment with reduced hepatic side effects.

Estradiol may limit lipid oxidation via Cpt 1 expression and hormonal mechanisms

OBJECTIVE

Evidence indicates that estrogen depresses hepatic lipid oxidation. We tested the hypothesis that estradiol (E(2)) treatment depresses transcription of carnitine palmitoyltransferase-1 (Cpt 1) mRNA and increases adiposity.

RESEARCH METHODS AND PROCEDURES

Six ovariectomized female rats were given a subcutaneous pellet of E(2) (5 mg/d), and six were given placebo. Rats were pair-fed by group for 18 days. Body composition was assessed chemically: mRNA for liver Cpt 1, adipose tissue uncoupling protein-2 (Ucp 2), and quadriceps Ucp 3 by Northern analysis; serum glucose, triglycerides (TGs), and free fatty acids by standard techniques; and serum insulin and glucagon by radioimmunoassay.

RESULTS

E(2)-treated rats lost more weight than placebo-treated rats (37.3 +/- 6.0 vs. 16.2 +/- 2.6 g, p < 0.01), but did not differ in final carcass composition (adjusted for eviscerated body mass). E(2)-treated rats had lower liver Cpt 1 (p < 0.001) and skeletal muscle Ucp 3 (p < 0.05) mRNA and lower concentrations of glucose, glucagon, and free fatty acids (p < 0.05). E(2)-treated rats tended to have higher insulin (p = -0.067) and TG (p = 0.097). TG tended to be correlated with Cpt 1 mRNA (r = -0.56 and p = 0.07).

DISCUSSION

These results suggest that, although E(2) is likely to suppress lipid oxidation and promote TG synthesis, these effects are not manifested in a relative increase in carcass adiposity after 18 days of treatment, at least under conditions of negative energy balance. The possible role of E(2)-mediated changes in insulin and glucagon secretion on hepatic substrate metabolism warrants further study.

Drug-Induced lipid changes: a review of the unintended effects of some commonly used drugs on serum lipid levels

Many drugs besides lipid-lowering drugs affect serum lipid levels in either a potentially harmful or beneficial way, and may therefore increase or decrease the risk of cardiovascular disease. Diuretics, beta-blocking agents, progestogens, combined oral contraceptives containing 'second generation' progestogens, danazol, immunosuppressive agents, protease inhibitors and enzyme-inducing anticonvulsants adversely affect the lipid profile. They increase total cholesterol, low density lipoprotein cholesterol and triglycerides by up to 40, 50 and 300%, respectively, and decrease high density lipoprotein cholesterol by a maximum of 50%. Conversely, alpha-blocking agents, estrogens, hormone replacement therapy, combined oral contraceptives containing 'third generation' progestogens, selective estrogen receptor modulators, growth hormone and valproic acid show mostly beneficial effects on the lipd profile. Some drugs, for example, isotretinoin, acitretin and antipsychotics, mainly elevate triglyceride levels. Adverse or beneficial effects on serum cholesterol levels do not always translate into a higher or lower, respectively, incidence of cardiovascular disease. because these drugs may influence cardiovascular risk through multiple pathways. In some cases, excessive cholesterol levels occur, for example, with protease inhibitor therapy, and several cases of pancreatitis attributable to drug-induced hypertriglyceridaemia have been reported. Some general guidelines on the management of drug-induced dyslipidaemia can be given. Replacement of the dyslipidaemia-inducing drug by an equivalent alternative therapy is preferred. However, such alternatives are often difficult to find. If there is no equivalent alternative and treatment with the dyslipidaemia-inducing drug must be initiated, monitoring of serum lipid levels is important. If drug use is expected to be long term, the existing guidelines for the management of dyslipidaemia in the general population can be applied to drug-induced dyslipidaemia. In cases of extreme hyperlipidaemia, medication use should be reassessed.

Effects of postmenopausal hormone replacement therapy on lipid, lipoprotein, and apolipoprotein (a) concentrations: analysis of studies published from 1974-2000

OBJECTIVE

To establish reference estimates of the effects of different hormone replacement therapy (HRT) regimens on lipid and lipoprotein levels.

DESIGN

Review and pooled analysis of prospective studies published up until the year 2000.

SETTING

Clinical trials centers, hospitals, menopause clinics.

PATIENT(S)

Healthy postmenopausal women.

INTERVENTION(S)

Estrogen alone, estrogen plus progestogen, tibolone, or raloxifene in the treatment of menopausal symptoms.

MAIN OUTCOME MEASURE(S)

Serum high- and low-density lipoprotein (HDL and LDL) cholesterol, total cholesterol, triglycerides, and lipoprotein (a).

RESULT(S)

Two-hundred forty-eight studies provided information on the effects of 42 different HRT regimens. All estrogen alone regimens raised HDL cholesterol and lowered LDL and total cholesterol. Oral estrogens raised triglycerides. Transdermal estradiol 17-beta lowered triglycerides. Progestogens had little effect on estrogen-induced reductions in LDL and total cholesterol. Estrogen-induced increases in HDL and triglycerides were opposed according to type of progestogen, in the order from least to greatest effect: dydrogesterone and medrogestone, progesterone, cyproterone acetate, medroxyprogesterone acetate, transdermal norethindrone acetate, norgestrel, and oral norethindrone acetate. Tibolone decreased HDL cholesterol and triglyceride levels. Raloxifene reduced LDL cholesterol levels. In 41 studies of 20 different formulations, HRT generally lowered lipoprotein (a).

CONCLUSION(S)

Route of estrogen administration and type of progestogen determined differential effects of HRT on lipid and lipoprotein levels. Future work will focus on the interpretation of the clinical significance of these changes.

Micronized progesterone: clinical indications and comparison with current treatments

OBJECTIVE

To integrate and evaluate the pharmacokinetic, endocrine, and clinical effects of micronized progesterone formulations.

DESIGN

Published articles concerning the pharmacokinetics of orally administered progesterone and the potential clinical uses of oral micronized progesterone were reviewed. Results concerning their use for secondary amenorrhea, premenopausal bleeding disorders, luteal phase dysfunction, termination of premature labor, hormone replacement therapy, and premenopausal syndrome are summarized. Critical issues to be resolved through ongoing preclinical and clinical research are highlighted.

RESULT(S)

Because of the enhanced bioavailability of oral micronized progesterone, the compound may be useful for a variety of therapeutic indications. Oral micronized progesterone is available in France, and a formulation recently has been approved in the United States for the treatment of secondary amenorrhea and postmenopausal hormone replacement therapy. A large body of evidence, including the Postmenopausal Estrogen/Progestin Interventions study, suggests that the use of a combination of estrogen and oral micronized progesterone is optimal for long-term hormone replacement therapy. There also are data indicating that oral micronized progesterone could be of potential use for the treatment of premenopausal bleeding disorders, luteal phase disorders, and premature labor.

CONCLUSION(S)

Oral micronized progesterone has widespread clinical potential, particularly for the treatment of secondary amenorrhea and dysfunctional premenopausal bleeding, and as a component of postmenopausal hormone replacement therapy.

The effect of percutaneous oestradiol on atheroma formation in ovariectomized cholesterol-fed rabbits

OBJECTIVE

The aim of this study was to examine the effect of percutaneous oestradiol on the lipid profile and on atheroma formation using an animal model.

METHODS

The study was of 12 weeks duration. Fifty sexually mature female New Zealand White rabbits were divided into five groups of equal size. Two groups acted as controls and received normal rabbit chow. Rabbits in one of these groups were ovariectomized. The remaining three groups were ovariectomized but received 1% cholesterol enriched rabbit chow. One of these cholesterol-fed groups received 0.3 mg/kg percutaneous oestradiol daily whilst another received 0.1 mg/kg oral oestradiol daily. Measurements of concentrations of total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and triglycerides (TG) were made at the beginning and end of the study. Aortic atheroma formation was measured using computerized image analysis of uptake of Sudan III staining.

RESULTS

After 12 weeks there were significant increases in the mean concentrations of TC in the three cholesterol-fed groups compared with controls (P < 0.001). Changes in HDL-C and TG concentrations were less consistent. The mean area of aortic atheroma formation was significantly less in both the percutaneous oestradiol group (4.9%) and the oral oestradiol group (8.6%) compared with the non-oestrogen-treated cholesterol-fed group (19.5%) (P < 0.001, < 0.01 respectively).

CONCLUSION

These results suggest that percutaneous oestradiol has a direct protective effect on atheroma formation independent of serum concentrations of total cholesterol.

Oral micronized progesterone

This review sought to examine the rationale for selecting an oral micronized progesterone formulation rather than a synthetic progestin for some of the main indications for progestogens. Unopposed estrogen use is associated with a high risk (relative risk, 2.1 to 5.7) of endometrial hyperplasia and adenocarcinoma, and it has been understood for some time that a progestogen must be added for at least 10 to 14 days per month to prevent these effects. However, the most commonly used synthetic progestins, norethisterone and medroxyprogesterone acetate, have been associated with metabolic and vascular side effects (eg, suppression of the vasodilating effect of estrogens) in both experimental and human controlled studies. All comparative studies to date conclude that the side effects of synthetic progestins can be minimized or eliminated through the use of natural progesterone, which is identical to the steroid produced by the corpus luteum. The inconvenience associated with the use of injectable, rectal, or vaginal formulations of natural progesterone can be circumvented by using orally administered micronized progesterone. The bioavailability of micronized progesterone is similar to that of other natural steroids, and interindividual and intraindividual variability of area under the curve is similar to that seen with synthetic progestins. A clear dose-ranging effect has been demonstrated, and long-term protection of the endometrium has been established. Micronized progesterone has been used widely in Europe since 1980 at dosages ranging from 300 mg/d (taken at bedtime) 10 days a month for women wishing regular monthly bleeding to 200 mg 14 days a month or 100 mg 25 days a month for women willing to remain amenorrheic. This therapy is well tolerated, with the only specific side effect being mild and transient drowsiness, an effect minimized by taking the drug at bedtime. The prospective, comparative Postmenopausal Estrogens/Progestin Intervention trial has recommended oral micronized progesterone as the first choice for opposing estrogen therapy in nonhysterectomized postmenopausal women.

Effects of oral combined hormone replacement therapy on plasma lipids and lipoproteins

Hormone replacement therapy has been shown to decrease the risk of coronary heart disease (CHD) in menopausal women. In this cross-sectional study, we addressed the following question: What effects would combined oral hormone replacement therapy have on plasma lipid and lipoprotein profiles independent of the other known CHD risk factors? We analyzed the plasma lipoproteins of two groups of menopausal women who were randomly selected from a large database of individuals. One group (n = 10) was not taking any hormone replacement therapy (NO HRT), while the second group (n = 8) was taking a daily dose of 0.625 mg conjugated estrogen and 2.5 mg medroxyprogesterone orally (PremPro, Wyeth-Ayerst, Philadelphia, PA) for at least 6 months (HRT). The two groups were not different in age, body weight, percent body fat, body mass index (BMI), waist to hip ratio, blood pressure, or insulin and glucose levels. High-density lipoprotein (HDL)-cholesterol was significantly higher (P < .05) in the HRT group. The total cholesterol (TC) to HDL-cholesterol ratio was significantly lower for HRT versus NO HRT (P < .05). Apolipoprotein (apo) A-1, the apo A-1/B ratio, and lecithin:cholesterol acyltransferase (LCAT) activity were significantly higher in HRT (P < .05). Lipoprotein subclass profiles measured by nuclear magnetic resonance (NMR) spectroscopy showed an increase in larger HDL subpopulations (H3 and H4) in HRT (P < .05), which are considered antiatherogenic. No differences were seen in the cholesterol concentration or size of low-density lipoprotein (LDL) subpopulations in HRT compared with NO HRT. These results indicate that the combined estrogen and progesterone treatment leads to beneficial effects on plasma lipoproteins. The beneficial effects include (1) increases in HDL-cholesterol and predominance of HDL2, (2) no adverse effects on LDL subpopulation distribution, and (3) increases in apo A-1 levels and LCAT activity, which indicate an improvement in reverse cholesterol transport.

Estradiol therapy combined with progesterone and endothelium-dependent vasodilation in postmenopausal women

BACKGROUND

Epidemiological studies indicate that estrogen replacement therapy decreases the risk of cardiovascular events in postmenopausal women. Estrogen may confer cardiovascular protection by improving endothelial function because it increases endothelium-dependent vasodilation. It is not known whether progesterone attenuates the beneficial effects of estrogen on endothelial function.

METHODS AND RESULTS

Seventeen postmenopausal women with mild hypercholesterolemia were enrolled in a placebo-controlled, crossover trial to evaluate the effect of transdermal estradiol, with and without vaginal micronized progesterone, on endothelium-dependent vasodilation in a peripheral conduit artery. Brachial artery diameter was measured with high-resolution B-mode ultrasonography. To assess endothelium-dependent vasodilation, brachial artery diameter was determined at baseline and after a flow stimulus induced by reactive hyperemia. To assess endothelium-independent vasodilation, brachial artery diameter was measured after administration of sublingual nitroglycerin. During estradiol therapy, reactive hyperemia caused an 11.1+/-1.0% change in brachial artery diameter compared with 4. 7+/-0.6% during placebo therapy (P<0.001). Progesterone did not significantly attenuate this improvement. During combined estrogen and progesterone therapy, flow-mediated vasodilation of the brachial artery was 9.6+/-0.8% (P=NS versus estradiol alone). Endothelium-independent vasodilation was not altered by estradiol therapy, either with or without progesterone, compared with placebo. There was a modest decrease in total and LDL cholesterol during treatment both with estradiol alone and when estradiol was combined with progesterone (all P<0.001 versus placebo). In a multivariate analysis that included serum estradiol, progesterone, total and LDL cholesterol concentrations, blood pressure, and heart rate, only the estradiol level was a significant predictor of endothelium-dependent vasodilation.

CONCLUSIONS

The addition of micronized progesterone does not attenuate the favorable effect of estradiol on endothelium-dependent vasodilation. The vasoprotective effect of hormone replacement therapy may extend beyond its beneficial actions on lipids.

Effects of hormone replacement therapy on the endometrium and lipid parameters: a review of randomized clinical trials, 1985 to 1995

The association between unopposed estrogen replacement therapy and endometrial hyperplasia and endometrial cancer in nonhysterectomized postmenopausal women is well known, and studies have suggested that the addition of progestin to the regimen reduces the risk of hyperplasia and cancer. The effect of estrogen plus progestin hormone replacement therapy on the lipid profile has also been extensively studied. To determine the extent of the effects of hormone replacement therapy on the endometrium and lipid parameters and to provide an overview of these studies, we reviewed 10 years of English language publications.

Metabolic changes induced by peroral oestrogen and transdermal oestradiol gel therapy

OBJECTIVE

To investigate changes in plasma lipid and lipoprotein levels induced by peroral oestrogen replacement and transdermal oestradiol gel therapy.

DESIGN

The effects of peroral oestradiol valerate tablets (2 mg) and placebo gel were compared with 1g transdermal oestradiol gel (1mg oestradiol) and placebo tablets in a randomised, double-blind, double-dummy study for 6 months.

SETTING

Department of Internal Medicine, University of Oulu and Oulu Deaconess Institute, Oulu, Finland.

POPULATION

Seventy-nine hysterectomised, postmenopausal women, 39 women in the peroral oestrogen group and 40 in the gel group.

MAIN OUTCOME MEASURES

Cholesterol and triglycerides in total plasma and in various lipoprotein fractions, and sex hormones.

RESULTS

In the peroral oestrogen group total and LDL cholesterol were decreased and HDL cholesterol and triglycerides were increased. In the oestradiol gel group plasma total, LDL and VLDL cholesterol and the ratio of LDL/HDL cholesterol were significantly decreased, but no change in HDL cholesterol and triglycerides was observed. Overall the decrease in LDL levels was correlated with the increase in oestrogen levels.

CONCLUSIONS

Both peroral and transdermal replacement therapy had beneficial effects on plasma lipids by lowering total and LDL cholesterol and LDL/HDL cholesterol ratio. These changes seem to be associated with changes in oestrogen levels.

Impact of combined hormone replacement therapy on serum lipid metabolism: new aspects

The objective of this study was to evaluate the impact of combined estrogen-progestogen therapy on low density lipoprotein (LDL) particle size (determined by the LDL cholesterol/apolipoprotein B ratio). The prospective study was carried out on 139 healthy Danish early postmenopausal women. The subjects were randomized to placebo or to 2 mg estradiol valerate equivalents, either sequentially combined with 75 micrograms levonorgestrel, 10 mg medroxyprogesterone acetate (MPA), or 150 micrograms desogestrel, or continuously combined with 1 mg cyproterone acetate. LDL particle size was calculated before treatment and at nine-well-defined times during the subsequent 84 days. LDL particle size was reduced by all four treatments. This change was statistically significant for estradiol valerate combined with levonorgestrel and MPA (6.2 +/- 2.7% and 5.6 +/- 2.1% (mean +/- SEM), respectively; p < 0.05 for both, placebo-corrected). Estradiol valerate combined with MPA induced cyclic (progestogen-minus estrogen-related values) decreases (-6.3 +/- 2.6%; p < 0.05), and with levonorgestrel there were cyclic increases (5.1 +/- 2.7%; p = 0.067) in LDL particle size (placebo-corrected). In conclusion, combined estrogen-progestogen therapy causes a decrease in LDL particle size. A cyclic variation in LDL cholesterol/apolipoprotein B ratio was observed during sequential treatment.

Long-term influence of different postmenopausal hormone replacement regimens on serum lipids and lipoprotein(a): a randomised study

OBJECTIVE

To assess the influence of three different postmenopausal hormone replacement therapies on levels of serum lipids and lipoprotein(a) [Lp(a)].

DESIGN

Open, randomised, controlled study.

PARTICIPANTS

One hundred and forty healthy, early postmenopausal women.

INTERVENTIONS

The women were randomised to receive continuous 17 beta-oestradiol, either orally (2 mg daily; n = 35) or transdermally (50 micrograms daily; n = 35), plus 10 mg dydrogesterone daily for 14 days of each 28-day cycle; or 2.5 mg tibolone daily (n = 35). Thirty-five untreated women acted as controls.

MAIN OUTCOME MEASURES

Fasting blood samples were analysed at baseline, 6, 12 and 24 months for low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol, very low density lipoprotein (VLDL), total cholesterol, triglycerides, lipoprotein(a)[Lp(a)], apolipoproteins A-1, A-2 and B, fibrinogen, and antithrombin factor III.

RESULTS

At 24 months oral oestradiol increased mean HDL cholesterol (7%; 95% CI 1-14), compared with no change in the transdermal group and a decrease of 26.8% in the tibolone group (95% CI 22.9-30.5); oral oestradiol decreased mean LDL cholesterol (11.8%; 95% CI 6.3-19), compared with no change in the tibolone group. Changes in apolipoprotein A-1 and B showed a similar pattern to HDL and LDL cholesterol, respectively. Oral oestradiol increased serum triglycerides (30%; 95% CI 18-42) after 24 months, compared with no change in the tibolone and transdermal oestradiol groups. Tibolone decreased serum Lp(a) by 36.6% after 24 months (95% CI 8.3-56.2), oral oestradiol decreased levels by 29.4% (95% CI 2-51.1), compared with no change in the transdermal oestradiol group.

CONCLUSIONS

Oral and to a lesser extent transdermal oestradiol when sequentially combined with dydrogesterone, showed a beneficial influence on serum lipids regarding the cardiovascular disease risk, which was not seen with tibolone. The significance of Lp(a) levels on cardiovascular disease risk remains to be determined.

Responses of HDL subclasses, Lp(A-I) and Lp(A-I:A-II) levels and lipolytic enzyme activities to continuous oral estrogen-progestin and transdermal estrogen with cyclic progestin regimens in postmenopausal women

Seventy postmenopausal women took part in the study. Subjects received either continuous oral 17 beta-estradiol 2 mg/day combined with norethisterone acetate 1 mg/day (E2/NETA, Kliogest) or transdermal treatment consisting of 28 day cycles with patches delivering 17 beta-estradiol 50 micrograms/day (Estraderm) combined with cyclic medroxyprogesterone acetate 10 mg/day (E2/MPA, Provera), on days 17-28. At baseline the serum lipid and lipoprotein concentrations, composition and concentrations of high density lipoprotein (HDL) subclasses, lipoprotein (Lp)(AI) and Lp(A-I:A-II) levels were comparable in the two groups. In the E2/NETA group, after 12 months hormone replacement therapy (HRT), the HDL2 cholesterol concentration decreased by 17% (P < 0.01) and the HDL3 cholesterol remained unchanged. The concentrations of HDL2b, HDL2a and HDL3a were reduced by 30, 26 and 15%, respectively, P < 0.001, and the cholesterol:triglyceride ratio decreased significantly in all HDL subclasses. Apolipoprotein (apo) A-I concentration decreased by 5% (P < 0.05), but apo A-II, Lp(A-I) and Lp(A-I:A-II) concentrations remained unchanged. In the E2/MPA group the HDL2 and HDL3 cholesterol levels were both reduced by 6% (P < 0.05) and the HDL3a, HDL3b and HDL3c concentrations decreased by 14, 12 and 17% during the E2/MPA phase compared with baseline (P < 0.01). No major changes in the composition of HDL subclasses occurred in the E2 MPA group during treatment. The apo A-I and Lp(A-I) levels were not changed, but apo A-II and Lp(A-I:A-II) concentrations decreased by 8 and 5%, P < 0.001 and P < 0.05, respectively. At 12 months the postheparin plasma hepatic lipase (HL) activity decreased only in the E2/NETA group (by 12%, P < 0.05). The cholesteryl ester transfer protein (CETP) activity was not affected by either HRT regimen. The results of our study show that the 2 HRT regimens have multiple effects on HDL particles and HRT induced changes in HDL are not associated with changes in activities of lipolytic enzymes or CETP.

Biologic effects of 17 alpha-dihydroequilin sulfate

OBJECTIVE

To determine the independent biologic effects of 17 alpha-dihydroequilin sulfate.

DESIGN

Prospective randomized study.

SETTING

University of Southern California Medical Center.

PATIENTS(S)

Twenty-one postmenopausal women, mean age 50 +/- 2 (+/-SEM) years, and mean body mass index 27 +/- 2.

INTERVENTION(S)

Women were randomized to receive daily oral doses of either 1.25 mg of estrone sulfate (E1S), 0.2 mg of 17 alpha-dihydroequilin sulfate, or a combination. Three blood and urine samples were obtained before and after 30 and 90 days of treatment.

RESULT(S)

After 30 and 90 days of treatment, E1S alone increased sex hormone-binding globulin (SHBG) levels significantly, 19.7% +/- 6.0% and 61.3% +/- 13.0%, whereas 17 alpha-dihydroequilin sulfate reduced SHBG levels, 20.8% +/- 68% and 12.4% +/- 7.5%, respectively. Nevertheless, the combination of E1S and 17 alpha-dihydroequilin sulfate significantly increased SHBG levels, 103% +/- 27.9% and 98.2% +/- 19.1%, compared with baseline at 30 and 90 days. Fewer changes were evident with corticosteroid-binding globulin (CBG). After 90 days of treatment, CBG levels significantly increased 30.9% +/- 5.5% with E1S, decreased by 7.2% +/- 5.0% with 17 alpha-dihydroequilin sulfate, and, with the combination, significantly increased by 10.5% +/- 2.4% compared with baseline. Changes in lipids and lipoproteins were more variable. However, high-density-lipoprotein cholesterol increased significantly with E1S at 30 and 90 days compared with baseline, 96.5% +/- 39% and 91.5% +/- 22.6%, and with the combination increased 66.4% +/- 13.3% and 79.2% +/- 24.4%, respectively. Fewer changes were evident with 17 alpha-dihydroequilin sulfate alone, decreasing 4.4% +/- 22% and 2.6% +/- 21.3%. Urinary ratios of bone collagen equivalents-creatinine and calcium-creatinine decreased in all three groups. However, the combination group resulted in a significantly greater percentage decrease in bone collagen equivalents-creatinine than with E1S alone.

CONCLUSIONS(S)

17 alpha-Dihydroequilin sulfate could modify some of the first-pass effects of conjugated equine estrogens and act synergistically with other conjugated equine estrogens to reduce bone resorption.

The menopause and hormone replacement therapy: lipids, lipoproteins, coagulation and fibrinolytic factors

OBJECTIVES

To review the recent literature concerning the effects of the menopause and hormone replacement therapy (HRT) on the plasma lipoprotein and hemostatic system, as well as on the interaction between these two coronary heart disease (CHD) risk factor systems. METHODS. Collection of information from relevant scientific journals, and by the use of Medline and Current Contents.

RESULTS

The mainly beneficial effects of unopposed oral estrogen replacement on the plasma lipoprotein pattern are preserved to different degrees after addition of progestin to the regimen. Nortestostorone-derived progestins tend to lower HDL cholesterol levels more than progesterone derivatives. The slight triglyceride-elevating effect on conjugated equine estrogens was in a large study not significantly counteracted by progesterone derivatives but can, according to other studies, be reversed by nortestosterone-derived progestins. A limited number of studies on transdermal administration of estradiol has suggested that the effects on plasma lipoproteins are smaller than during oral administration. There is no convincing evidence that currently used HRT regimens would significantly increase the risk of thrombosis. Nevertheless, the finding in some studies that plasma triglyceride elevations could in theory be associated with impaired fibrinolysis and enhanced coagulation merit further attention as some HRT regimens tend to increase plasma triglyceride levels. From a theoretical point of view, transdermal estrogen delivery would be preferable in women at risk for thrombosis, as they have less pronounced effects on liver functions, including production of hemostatic factors and very-low-density lipoprotein triglycerides.

CONCLUSIONS

While the numerous existing HRT regimens provide many alternative and useful possibilities, further studies are needed concerning (a) novel progestins with minimal HDL cholesterol lowering effects, (b) transdermal and other non-oral routes for HRT, (c) possible antioxidative properties of estrogen and (d) metabolic links between the lipoprotein and hemostatic risk factor systems.

The effect of percutaneous oestrogen replacement therapy on Lp(a) and other lipoproteins

OBJECTIVES

To determine the effect of percutaneous oestrogen replacement therapy on lipoprotein (a) and other plasma lipoproteins.

METHODS

Open longitudinal prospective study conducted at the hormone replacement clinic of the Prince of Wales Hospital, New Territories, Hong Kong. Thirty women who had undergone a total abdominal hysterectomy and bilateral salpingo-oophorectomy for benign gynaecological conditions were treated with 1.5 mg of percutaneous 17 beta-oestradiol gel applied daily for a period of 12 consecutive months. Measurements of plasma lipoproteins were made before the commencement of treatment and repeated at 6- and 12-month intervals.

RESULTS

There was a significant reduction in the concentrations of Lp(a) during the first 6 months of treatment, with median values falling from 7.87 mg dL-1 to 6.16 mg dL-1 (P = 0.004, 0-6 months). During the second 6 months, the median concentration increased to 9.38 mg dL-1, (P = 0.072, 6-12 months), which did not significantly differ from the baseline level (P = 0.545, 0-12 months). Significant reductions in the concentrations of apoprotein A-I (apo A-I), apoprotein B (apo B), high density lipoprotein cholesterol (HDL-C), and HDL3-C were also present after 6 months (P = 0.043, 0.049, 0.028, 0.013, respectively), but there were no differences between the baseline values of these lipoproteins and those at the completion of the study (P = 0.948, 0.244, 0.839, 0.117 respectively). Drug compliance was maintained throughout the study, with similar mean oestradiol concentrations at 6 and 12 months.

CONCLUSIONS

The percutaneous administration of 17 beta-oestradiol has variable short term effects on plasma lipoproteins which are not maintained over a longer duration of treatment. By avoiding the 'first pass' effect on the liver, this method of delivery does not appear to produce the sustained changes in lipoproteins seen with oral treatment.

Ovariectomy decreases plasma triglyceride levels in analbuminaemic rats by lowering hepatic triglyceride secretion

In mutant analbuminaemic rats (NAR), females demonstrate a more marked hypertriglyceridaemia than males. Ovariectomy decreases triglyceride levels in female NAR. We measured triglyceride secretion rates in vivo as well as the activity of acetyl CoA carboxylase (ACC) and fatty acid synthase (FAS) in hepatic cytosol obtained from female control Sprague-Dawley (SD) rats and NAR with or without ovariectomy. NAR were severely hyperlipidaemic, and triglyceride, cholesterol, apolipoprotein A-I and plasma protein concentrations levels were decreased (all P < 0.01) by ovariectomy. Only triglyceride levels were decreased by ovariectomy in the SD rats (P < 0.05). Oestradiol treatment in ovariectomized NAR restored plasma protein and triglyceride concentrations to levels similar to those observed in intact female NAR and caused a marked increase in plasma cholesterol. Ovariectomy in NAR reduced lipoprotein triglycerides and cholesterol in VLDL, IDL and LDL1, but had little effect on the triglyceride-cholesterol ratio of these particles. Both ACC and FAS activities were markedly increased in NAR vs. SD rats (P < 0.01). This increase was partially corrected by ovariectomy. There was no significant effect of ovariectomy on ACC or FAS activity in the SD rats. Triglyceride secretion rates were significantly increased in NAR vs. SD rats (135 +/- 10 vs. 103 +/- 12 nmol/min per 100 g body weight; P < 0.05). Ovariectomy markedly decreased triglyceride secretion rate in NAR to 69 +/- 6 (P < 0.01), but not in SD rats (92 +/- 8 nmol/min per 100 g body weight, NS). Oestradiol treatment in ovariectomized SD rats restored triglyceride levels but had no significant effect on triglyceride secretion rate (106 +/- 23 nmol/min per 100 g).(ABSTRACT TRUNCATED AT 250 WORDS)

Danazol and plasma lipoprotein metabolism

The potential long-term impact of danazol on coronary risk hinges on its effect on lipoprotein metabolism rather than its influence on total plasma lipids. Danazol may exert a regulatory influence on three key processes in lipoprotein metabolism: hepatic lipase activity; low-density lipoprotein receptor function; and lecithin:cholesterol acyl-transferase activity. Danazol decreases plasma fibrinogen and lipoprotein (a) levels, promotes fibrinolysis and causes a rise in plasminogen. Such changes are beneficial as they inhibit the process of thrombosis. Androgenic properties of danazol produce effects of plasma lipids and lipoproteins which oppose estrogen-induced changes. The usual recipients of danazol therapy are premenopausal females, in whom the absolute risk of ischemic heart disease is low. If the drug were shown to increase ischemic heart disease risk, detrimental factors must be weighted against its considerable and proven clinical benefits.

A prospective two-year study of progestin given alone in postmenopausal women: effect on lipid and metabolic parameters

OBJECTIVE

A controlled study was conducted to assess the long-term effect of a progestin with very low androgenic potency given alone on serum lipoprotein profile, serum renin substrate, sex hormone-binding globulin levels, and serum antithrombin III activity in early postmenopausal women.

STUDY DESIGN

Thirty-five early postmenopausal women who had not received any form of hormonal treatment after menopause were randomly assigned to a 2-year regimen of 500 micrograms of a progestin derived from 19-norprogesterone (promegestone) or a placebo for 21 days of a 28-day treatment cycle. Serum lipid and lipoprotein levels and other biochemical parameters were measured in the two groups, and differences were sought by statistical analysis.

RESULTS

After 2 years of treatment the women in the two groups showed no statistically significant variation from baseline values in the concentrations of any of the biochemical parameters studied.

CONCLUSIONS

The results show that a progestin with very low androgenic activity given alone has no influence on lipid profile and hepatic synthesis of several proteins in early postmenopausal women.

Phasic serum lipid excursions occur during cyclical oral conjugated oestrogens but not during transdermal oestradiol sequentially combined with oral medroxyprogesterone acetate

BACKGROUND AND OBJECTIVE

Recent data indicate that oral medroxyprogesterone acetate (MPA) has limited unfavourable, neutral or even favourable effects on serum lipid fractions when added to oestrogen replacement therapy. The purpose of this study was to evaluate the serum lipid fractions at the beginning and at the end of each phase of a sequentially combined replacement cycle comparing the oral and the transdermal routes of oestrogen administration.

DESIGN

Randomized study with a matched control group. Oral conjugated oestrogens (OCE, 0.625 mg) or transdermal oestradiol (TE 50 micrograms) was taken from day 1 to day 25 and MPA (5 mg) added on days 14 to 25. Serum lipids were evaluated on days 1, 14 and 25 of monthly replacement cycles.

PATIENTS

The early post-menopausal women in the control group (n = 11) and in the treatment groups (OCE/MPA, n = 15; TE/MPA, n = 17) were evaluated every 3 months for 12 months and every 6 months for another 12 months.

MEASUREMENTS

Serum levels of triglycerides (TG), cholesterol (C) fractions and apolipoproteins (Apo) and their respective ratios were measured at months 1, 3, 6, 9, 12, 18, 24. Menopausal symptoms and uterine bleedings were evaluated in parallel and an endometrial biopsy was performed at the end of the 12th and 24th months of treatment.

RESULTS

After 14 days of OCE, C, LDL-C, and Apo B were decreased and TG, HDL-C and Apo A1 were increased. The sequential addition of MPA accentuated the reduction of LDL-C and Apo B but attenuated the elevation of TG, HDL-C and Apo A1. These changes tended to revert toward baseline during the period free of medication. By contrast, at the end of 14 days of TE there was a non-significant reduction in TG and LDL components and a limited increase in HDL-C and Apo A1. During the subsequent addition of MPA there was no significant decrease in TG, LDL-C or Apo B but an elimination of the increase in HDL components. These combined changes resulted in a significant reduction in the LDL-C/HDL-C ratio and a significant elevation in the Apo A1/Apo B ratio only in the OCE/MPA group.

CONCLUSION

Overall, oral conjugated oestrogens induced favourable intragroup changes in cholesterol fractions whereas transdermal oestradiol maintained serum lipids at levels not different from baseline. The sequential addition of oral medroxyprogesterone acetate attenuated the beneficial elevation of HDL, did not affect the beneficial effect of oestrogens on ratios of cholesterol fractions and attenuated the unfavourable effect of oral conjugated oestrogens on triglycerides. The partial loss of beneficial effects on lipoproteins during cyclical interruption of hormone therapy would be an argument in favour of the evaluation of continuous regimens of oestrogen/progestagen replacement.

Effects of continuous low-dosage hormonal replacement therapy on lipoprotein metabolism in postmenopausal women

The effects on lipoprotein metabolism of female hormone replacement therapy (HRT) for 7 weeks with combined low dosages of a widely used oral progestin and estrogen combination, medroxyprogesterone acetate ([MPA] 2.5 mg/d) and conjugated equine estrogen ([CEE] 0.625 mg/d), were studied in six postmenopausal women. To investigate the mechanism of the reduction of low-density lipoprotein (LDL) cholesterol by HRT, the kinetics of very-low-density lipoprotein (VLDL) and LDL apolipoprotein (apo) B turnover were studied by injection of autologous 131I-labeled VLDL and 125I-labeled under control conditions and again in the fourth week of HRT. HRT induced (1) a 12% +/- 4% (P < .02) reduction of the cholesterol content of LDL of Sf 0-12, which was attributable to a 15% +/- 5% decrease in the mean ratio of cholesterol to apo B (1.3 +/- 0.1 v 1.5 +/- 0.1, P < .025), and (2) a 13% +/- 4% increase in the mean fractional catabolic rate (FCR) of LDL apo B (0.34 +/- 0.03 v 0.30 +/- 0.02 pools/d, respectively, P +/- .05). However, there were no significant changes in mean values for (1) pool size (42 +/- 4 v 43 +/- 3 mg/kg) or production rate (14 +/- 0.5 v 13 +/- 0.9 mg/kg/d, P > .1) of LDL apo B or (2) pool size (2.5 +/- 0.6 v 2.8 +/- 0.6 mg/kg), FCR (8.0 +/- 2.0 v 8.1 +/- 1.7 pools/d) or production rate (16 +/- 4 v 19 +/- 2 mg/kg/d, P > .4) [corrected] of VLDL apo B. HRT increased high-density lipoprotein (HDL) cholesterol concentration significantly (by 16% to 18%, P < .05), whereas the mean ratio of plasma total cholesterol to HDL cholesterol decreased by 19% +/- 3% (P < .005). HRT favorably influenced the overall plasma lipoprotein lipid vascular risk profile while significantly altering both the composition and fractional catabolism of LDL.

Endometrial hyperplasia: efficacy of a new treatment with a vaginal cream containing natural micronized progesterone

Seventy-eight premenopausal women affected by benign endometrial hyperplasia (60 simple and 18 complex) were treated from the 10th to the 25th day of the menstrual cycle with a vaginal cream containing 100 mg of natural micronized progesterone in polyethylene glycol base. The treatment lasted 3 months in 58 patients and 6 in the other 16 patients. Four patients were lost from the study. We observed a total of 67 complete regressions (90.5%) of which 58 (78.3%) occurred in the first 3 months and 9 (11.5%) after 6 months of treatment. Simple hyperplasia showed a significantly higher response to treatment in comparison with the complex type (P < 0.001). The most frequent endometrial pattern detected in the patients in whom hyperplasia regressed was of a secretive type. Recurrence of hyperplasia occurred in 1 out of 58 (1.72%) patients at the 3rd month and in 3 out of 49 (6.1%) patients at the 6th month after treatment. There were no significant differences between the two hystological groups in the percentage of recurrence. During treatment we observed a significant reduction of the amount, duration and frequency of the menstrual bleeding. Minimal side-effects were observed. In conclusion, for its effectiveness and safety, vaginal administration of natural micronized progesterone seems to be an interesting approach to benign endometrial hyperplasia, particularly indicated in women also affected by metabolic disorders.

Sex steroids and lipoprotein metabolism

Lipoprotein metabolism is involved in atherogenesis. Female sex-hormones have substantial effects on both lipoprotein metabolism and the vessel wall. Cholesterol, one of the major lipids in lipoproteins, is both the substrate for, and the target of, the steroidal sex hormones.

Relative value of transdermal and oral estrogen therapy in various clinical situations

OBJECTIVE

In this study, we reviewed the comparative effectiveness of transdermal and oral estrogen therapy in various groups of women.

DESIGN

On the basis of published data and personal clinical experience, we compiled recommendations for use of the various modes of estrogen replacement therapy.

MATERIAL AND METHODS

The use of injectable estrogen or implantable estrogen pellets can no longer be recommended because of their expense, inconvenience, and unphysiologic pattern of serum estrogen response. The two main estrogen preparations currently used in the United States--orally administered conjugated estrogens and transdermally administered estradiol--undergo different metabolism, and these processes are reflected in differing levels of circulating hormones and hepatic by-products, including blood clotting factors, binding proteins, renin substrate, and apolipoproteins, and in varied composition of the bile.

RESULTS

At least theoretically, transdermal estrogen therapy might be more beneficial than oral estrogen therapy for women who smoke cigarettes or who have migraine headaches, hypertriglyceridemia, hepatobiliary disorders, fibrocystic breast disease, or a history of thromboembolism. In contrast, women with hypercholesterolemia might respond better to oral than to transdermal estrogen therapy.

CONCLUSION

Additional properly designed clinical studies are necessary before these recommendations for estrogen replacement therapy can be validated or refuted.

Lack of demonstrated effect of nandrolone on serum lipids

Numerous prior studies of serum lipid levels during anabolic steroid (AS) use have uniformly demonstrated dramatic adverse lipid profiles (eg, average high-density lipoprotein [HDL] depression of 50%) during administration of 17 alpha-alkylated AS. In contrast, the existing studies of 17 beta-esterified AS have shown mild or absent lipid effects (eg, HDL depression 0% to 16%) with these agents. Thus, the potential effects on serum lipids of individual AS are an important clinical consideration. The present study was therefore designed to investigate the lipid effects of nandrolone, a 17 beta-esterified AS. Twenty-one men and three women had lipid profiles measured before and after administration of nandrolone decanoate 100 mg intramuscularly (IM) once a week for 6 weeks. No significant change was noted in HDL cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol, triglycerides, the total cholesterol to HDL-C ratio, or the LDL-C/HDL-C ratio from nandrolone treatment. Moreover, observed trends toward HDL-C depression (-2.00 +/- 8.83 mg/dL; values reported are for men only unless noted otherwise) and LDL elevation (+5.05 +/- 20.45 mg/dL) were small. In power analysis, HDL-C depressions of 6.3, 7.6, or 8.7 mg/dL during nandrolone were ruled out with powers of 80%, 95%, and 99%, respectively.

Dyslipoproteinemia in women and the elderly

Major risk factors predict coronary risk in both women and men. It is inadvisable and unwarranted to suggest that women be excluded from cholesterol screening. In fact, what evidence is available suggests that women, similar to men, benefit from cholesterol lowering. This is not an insignificant issue. Women, similar to men, die mostly of coronary atherosclerosis, although atherosclerotic death in women occurs 5 to 10 years later than in men. There are some risk factors that are unique in women. LDL-c levels may be less predictive of risk in women than in men; HDL-c levels may be more predictive. Triglycerides are a stronger predictor of risk in women than in men. Finally, diabetes is a major risk factor in women and almost eliminates the differences in risk seen in comparing nondiabetic men and women. Exogenous gonadal hormones, both in the form of OCs and HRT, have the potential to influence coronary risk in women. In premenopausal women, use of OCs is associated with increased risk of coronary disease in women who smoke, particularly in women older than age 35. In postmenopausal women, estrogen use is generally associated with protection against coronary disease. These results may be in part due to favorable effects on circulating lipoproteins but may as well be related to the protective effects of estrogen on the arterial wall. Definitive recommendations about the use of estrogen in postmenopausal women for the primary prevention of coronary disease await the completion of clinical trials of estrogen alone and in combination with progestins. Cholesterol and its lipoprotein subfractions continue to be predictors of both morbidity and mortality in older populations. The value of cholesterol-altering therapy in older individuals is not as well established in clinical trials as in middle-aged men. Nevertheless, there is good reason to believe that the results from both primary and secondary prevention studies in younger individuals can readily be extrapolated to older individuals. In particular, individuals with symptomatic coronary disease but a relatively good prognosis should be offered the same benefits from secondary prevention as younger individuals. Thus, although data are more limited in women and the elderly than in middle-aged men, there is good reason to believe that cholesterol interventions are likely to be effective, particularly in postmenopausal women and in older individuals with established coronary disease. To withhold therapy based simply on gender or chronologic age is a mistake.

Long-term hormone replacement treatment in menopause: new choices, old apprehensions, recent findings

In recent years there has been an increase in the use of parenteral oestradiol as an alternative to the conventional oral preparations used in hormone replacement treatment (HRT) in menopause, such as conjugated equine oestrogens (CEE). The latter have been subject in the past to apprehensions, partly due to misunderstanding and oversimplification but also in relation to problems that have arisen during the history of HRT, for example the increase in endometrial cancer risk deriving from the use of non-progestogen-opposed treatment. However, confidence in long-term HRT comes from the epidemiological findings, which refer mainly to the use of oral CEE unopposed by progestogen: a reduced risk of osteoporotic fractures and of cardiovascular disease, and a very limited risk of breast cancer. Oral oestrogens produce marked hepatocellular effects. These effects are, on the whole, favourable from the point of view of cardiovascular risk. In addition, it cannot be excluded that some hepatocellular effects of oral oestrogen, for example increased sex hormone binding globulin levels and reduced circulating insulin-like growth factor I activity, offer protection to the breast. As progestogen supplementation is needed in non-hysterectomized women, priority should be given to preparations, such as progesterone or dydrogesterone, that feature good endometrial activity without opposing oestrogen hepatocellular effects.

The role of reproductive hormones in vascular disease and hypertension

Review of pertinent research demonstrates a link between sex steroids and vascular disease. Evidence for this association includes: beneficial effect of estrogens on the blood lipids (elevation of high-density lipoproteins and lowering of low-density lipoproteins), adverse effect of high-dose synthetic estrogens on coagulation, vasodilating action of progesterone, and adverse effect of androgens and androgen-derived progestagens on lipoproteins. Natural steroids appear to differ in their impact from synthetic compounds; endogenous hormones from exogenous and parenterally administered preparations. Furthermore, steroids have different effects at different concentrations, doses, and ratios. Their actions also vary according to age, sex, pregnant or nonpregnant state, body weight, smoking, and other risk factors. In this article, the following areas will be considered in relation to the impact of sex steroids on cardiovascular phenomena and hypertension: menstrual cycle and its disturbances; amenorrhea and hyperandrogenism; pregnancy with its hyperdynamic state and a tendency to gestational hypertension; oral-contraception-induced, dose-related thromboembolic phenomena; menopause and estrogen deficiency states with increased incidence of atherogenesis; estrogen replacement therapy with its decrease in cardiovascular morbidity; other hormonal therapies which induce hypoestrogenism with its consequences. The evidence is emerging that hormonal modifications may be useful in the prevention of cardiovascular morbidity.

Effects of transdermal 17 beta-oestradiol combined with oral progestogen on lipids and lipoproteins in hypercholesterolaemic postmenopausal women

OBJECTIVES

The purpose of the study was to evaluate the effect of transdermal 17 beta-oestradiol with oral progestogen on the plasma levels of lipids, lipoproteins and apolipoproteins in hypercholesterolaemic postmenopausal women.

DESIGN

During 6 months of replacement therapy with transdermal 17 beta-oestradiol combined with oral progestogen, plasma lipids, lipoproteins and apolipoproteins after 3 and 6 months were measured and compared with pretreatment values by Student's t-test.

SETTING

From January 1992 until September 1992 patients were diagnosed and treated in an out-patient clinic of the Department of Endocrinology Medical Centre for Postgraduate Education, Warsaw.

SUBJECTS

The patients studied were 11 non-obese postmenopausal women with hypercholesterolaemia based on the World Health Organization criteria.

INTERVENTIONS

Venous blood samples were obtained before and 3 and 6 months after the beginning of cyclic replacement therapy with transdermal 17 beta-oestradiol (E2 100 micrograms day-1 combined with oral chlormadinone acetate (2 mg day-1 for 7 days in each cycle).

MAIN OUTCOME MEASURES

The antiatherogenic effect of transdermal oestrogen replacement therapy exerted by increased levels of high-density lipoprotein subfraction 2 cholesterol (HDL2-C) leading to the decrease of the total cholesterol level was anticipated.

RESULTS

After 6 months of the treatment the concentrations of HDL2 cholesterol (HDL2-C) increased from 0.45 +/- 0.07 mmol l-1 to 0.73 +/- 0.03 mol l-1 (P < 0.05) but the levels of HDL3 cholesterol (HDL3-C) decreased from 1.15 +/- 0.06 mmol l-1 to 0.89 +/- 0.07 mmol l-1 (P < 0.05). The concentrations of total cholesterol decreased from 6.9 +/- 0.13 mmol l-1 to 6.2 +/- 0.2 mmol l-1 (P < 0.05). No changes were observed in the plasma levels of total triglycerides, HDL cholesterol, low-density lipoprotein (LDL) cholesterol, very-low-density lipoprotein (VLDL) cholesterol, VLDL triglycerides, apolipoproteins A-I and B.

CONCLUSIONS

In hypercholesterolaemic postmenopausal women, transdermally administered 17 beta-oestradiol 100 micrograms daily in combination with oral chlormadinone acetate has a beneficial effect through raising the level of the antiatherogenic HDL2-C subfraction and decreasing the level of total cholesterol.

Response of plasma low density lipoprotein subfractions to oestrogen replacement therapy following surgical menopause

OBJECTIVE

Epidemiological studies suggest that postmenopausal oestrogen replacement reduces the incidence of cardiovascular disease. The purpose of this study was to establish the effects of oestrogen replacement therapy on subfractions of plasma low density lipoprotein in bilaterally oophorectomized women.

DESIGN

In a placebo controlled, double-blind study, patients were randomized on a two to one basis to receive either oestradiol valerate (2 mg/day) or placebo respectively for a period of 16 weeks.

PATIENTS

Seventeen women aged 28-51 years who had all had hysterectomy and bilateral oophorectomy at least 2 months before recruitment were assigned to either the active (n = 12) or placebo (n = 5) group.

MEASUREMENTS

Plasma lipids, lipoproteins, apolipoproteins and LDL subfractions were determined immediately before and after the treatment period. LDL subfractions were isolated directly from plasma by density gradient ultracentrifugation within 24 hours. Non-parametric statistical analysis was carried out within each group using Wilcoxon's signed rank test for matched pairs.

RESULTS

After 16 weeks of treatment, HDL cholesterol, apo A-I and HDL-2 were increased in the group receiving oestrogen (HDL cholesterol +12%, P < 0.01; apo A-I +14%, P < 0.01; HDL-2 +24% P < 0.01). While there were no significant changes in serum cholesterol, LDL cholesterol or triglycerides, the proportion and concentration of the least dense LDL-I subfraction was decreased significantly (-27%, P < 0.05). The LDL subfraction of intermediate density (LDL-II) was decreased in eight subjects, while small, dense LDL-III was unaffected. Overall, these changes resulted in an apparent shift in the distribution of LDL subfractions towards small, dense LDL-III, although there was no net increase in the latter.

CONCLUSION

In view of a similar and characteristic response of LDL subfractions to hypolipidaemic drugs that enhance the clearance of LDL via the LDL receptor, the present findings suggest that oestrogen promotes the preferential removal of LDL-I and II by activating LDL receptors. As this effect is normally associated with a reduction in the circulating level of LDL, it should not be regarded as an unfavourable response to oestrogen replacement therapy.