Risk of recurrent coronary events in relation to use and recent initiation of postmenopausal hormone therapy

Use of MHT in women with cardiovascular disease: a systematic review and meta-analysis

This systematic review assesses the effect of menopausal hormone therapy (MHT) on cardiovascular outcomes and risk factors in postmenopausal women with cardiovascular disease (CVD). The Medline, Embase and Cochrane databases were searched from inception to December 2022 for randomized controlled trials (RCTs) and observational studies using methodology from a previous Cochrane review. Quality assessment used the Cochrane risk of bias tool and Newcastle-Ottawa scale, respectively. From 5647 studies identified, 29 (23 RCTs and six observational studies) were included. Most studies were conducted in North America or Europe and investigated oral estrogens. Participants were older with varying frequency of cardiac risk factors and underlying CVD. No significant difference was observed between MHT users and controls regarding primary outcomes of non-fatal myocardial infarction, cardiovascular death or stroke. No difference in frequency of angina, heart failure and transient ischemic attacks was observed. Inconsistent effects of MHT on angiographic progression were seen and varied with glycemic status. Estradiol had a positive effect on flow-mediated dilatation. Limited studies identified differing effects of MHT on cardiac risk factors, varying with estrogen preparation. This study confirms no benefit of MHT for secondary CVD prevention, highlighting evidence limitations and the importance of shared decision-making when managing menopausal symptoms in women with CVD.

Increased longevity in older users of postmenopausal estrogen therapy: the Leisure World Cohort Study

OBJECTIVE

To examine the effect of postmenopausal estrogen therapy (ET), including duration and recency of use, on all-cause mortality in older women.

DESIGN

As part of a prospective cohort study of residents of a California retirement community begun in the early 1980s, Leisure World Cohort women (median age, 73 y) completed a postal health survey including details on ET use and were followed up for 22 years (1981-2003). Age- and multivariate-adjusted risk ratios (RR) and 95% CIs were calculated using proportional hazard regression.

RESULTS

Of the 8,801 women, 6,626 died during follow-up (median age, 88 y). ET users had an age-adjusted mortality rate of 52.9 per 1,000 person-years compared with 56.5 among lifetime nonusers (RR = 0.91; 95% CI, 0.87-0.96). Risk of death decreased with both increasing duration of ET and decreasing years since last use (P for trend < 0.001). The risk was lowest among long-term (≥15 y) users (RR = 0.83; 95% CI, 0.74-0.93 for 15-19 y and RR = 0.87; 95% CI, 0.80-0.94 for 201 y). For long-term users, the age-adjusted mortality rate was 50.4 per 1,000 person-years. Lower-dose users (≤0.625 mg) had a slightly better survival rate than higher-dose users (RR = 0.84; 95% CI, 0.78-0.91 vs RR = 0.91; 95% CI, 0.83-0.97). Risk did not differ by route of administration (P = 0.56). Further adjustment for potential confounders had little effect on the observed RRs for ET.

CONCLUSION

Long-term ET is associated with lower all-cause mortality in older women.

Decreased mortality risk due to first acute coronary syndrome in women with postmenopausal hormone therapy use

OBJECTIVES

The role of postmenopausal hormone therapy (HT) in the incidence of acute coronary syndrome (ACS) has been studied extensively, but less is known of the impact of HT on the mortality risk due to an ACS.

STUDY DESIGN AND MAIN OUTCOME MEASURES

We extracted from a population-based ACS register, FINAMI, 7258 postmenopausal women with the first ACS. These data were combined with HT use data from the National Drug Reimbursement Register; 625 patients (9%) had used various HT regimens. The death risks due to ACS before admission to hospital, 2-28, or 29-365days after the incident ACS were compared between HT users and non-users with logistic regression analyses.

RESULTS

In all follow-up time points, the ACS death risks in HT ever-users were smaller compared to non-users. Of women with HT ever use, 42% died within one year as compared with 52% of non-users (OR 0.62, p<0.001). Most deaths (84%) occurred within 28days after the ACS, and in this group 36% of women with ever use of HT (OR 0.73, p=0.002) and 30% of women with ≥5year HT use (OR 0.54, p<0.001) died as compared to 43% of the non-users. Age ≤60 or >60 years at the HT initiation was accompanied with similar reductions in ACS mortality risk.

CONCLUSIONS

Postmenopausal HT use is accompanied with reduced mortality risk after primary ACS.

Astragalin, a Flavonoid from Morus alba (Mulberry) Increases Endogenous Estrogen and Progesterone by Inhibiting Ovarian Granulosa Cell Apoptosis in an Aged Rat Model of Menopause

BACKGROUND

To determine the mechanism by which the flavonoid glycoside astragalin (AST) reduces ovarian failure in an aged rat model of menopause.

METHODS

The in vivo effect of AST on granulosa cell (GC) apoptosis in aged female rats was determined using flow cytometry. In vitro, the effects of AST on cultured GCs were investigated using the MTT proliferation assay and western blot assays.

RESULTS

Aged rats had significantly higher GC apoptosis as compared with young female rats. Treatment of aged rats with AST (all three doses; p < 0.01) or Progynova (p < 0.01) significantly reduced GC apoptosis as compared with the aged controls. The proportions of total apoptotic GCs was 25.70%, 86.65%, 47.04%, 27.02%, 42.09% and 56.42% in the normal, aged, 17β-estradiol (E₂), high dose AST, medium dose AST, and low dose AST-treated groups, respectively. Significant increases of serum E₂ and P₄ levels, as well as altered levels of serum follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels. In cultured rat GCs, AST stimulated GC proliferation, E₂ and progesterone (P₄) secretion, reduced apoptosis, reduced the level of the pro-apoptotic protein Bcl-2 (p < 0.01), but had no effect on BAX.

CONCLUSIONS

AST enhanced ovarian function in aged female rats by increasing E₂ and P₄ levels, and reducing ovarian GC apoptosis via a mechanism involving Bcl-2. These data demonstrate a new pharmacological activity for AST, as well as a novel mechanism of action, and further suggest that AST may be a new therapeutic agent for the management of menopausal symptoms.

Differences in the lipid profile and hormone replacement therapy use in Korean postmenopausal women: the Korea National Health and Nutrition Examination Survey (KNHANES) 2010-2012

Purpose

Hormonal changes after menopause can cause dyslipidemia by the cessation of endogenous estrogen. We analyzed the lipid profile of the Korean healthy menopausal women according to the use of hormone replacement therapy (HRT).

Methods

Data obtained from the Korea National Health and Nutrition Examination Survey (KNHANES) 2010–2012 were analyzed. The study included 428 healthy postmenopausal women with HRT (HRT group) and 1804 healthy postmenopausal women without HRT (NHRT group).

Results

After adjustment for confounding factors, total cholesterol (TC) and low-density lipoprotein (LDL) were lower in the HRT group than in the NHRT group (TC: 200.1 ± 2.0 vs. 204.9 ± 1.1, P = 0.04; LDL: 120.3 ± 1.0 vs. 124.5 ± 1.0 mg/ml, P = 0.033). Triglycerides (TG) were lower in the HRT group than in the NHRT group [106.8, (95 % CI 99.8–114.3) vs. 115.1 (95 % CI 111.8–118.5), P = 0.04]. Non-high-density lipoprotein (HDL) was lower in the HRT group than in the NHRT group (145.4 ± 1.9 vs. 151.2 ± 1.0 mg/ml, P = 0.008). Patients with HRT were lower in the LDL cholesterol level (OR 0.601, 95 % CI 0.397–0.917, P = 0.018), the total cholesterol to high-density lipoprotein ratio (OR 0.787, 95 % CI 0.617–0.997, P = 0.016), and the non-HDL level (OR 0.68, 95 % CI 0.509–0.907, P = 0.009).

Conclusion

The results of this study suggest that the use of HRT may have a positive effect on dyslipidemia in postmenopausal women.

Post-myocardial infarction hormone therapy revisited

Current guidelines recommend that postmenopausal hormone therapy should not be used in the setting of secondary prevention of coronary heart disease, and that it should be stopped when an acute coronary event occurs. Reviewing the available data on the issue of discontinuation of therapy in post-myocardial infarction patients shows that the basis for this recommendation is not so solid and clear-cut. In fact, the few relevant studies concluded that cessation of hormone therapy carried no benefit, and perhaps even caused some adverse cardiac events, when compared to women who continued with treatment after they suffered a coronary event. The following article uses a recently published study as an opportunity to review this topic. Based on the literature, my personal view is that long-term hormone users should not automatically withhold therapy post-myocardial infarction, but careful individual evaluation and consideration should precede any decision.

Pharmacological investigations of the unique herbal formula Menoprogen in rats: estrogenic activity and mechanism

The present study aimed to evaluate the pharmacological effects of Menoprogen in the management of menopausal symptoms for aged female rats. Menoprogen was supplemented to a group of elderly female rats for 8 weeks. Subsequently, histopathological examinations were conducted in the isolated uterine and ovary tissues and pituitary glands of the rats. Serum levels of estradiol (E(2)), progesterone (P), follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were determined. The ultrastructure of the rat ovarian granulocytes was analyzed. The histopathological examinations revealed no statistical difference in the quantity of follicles in the ovary and of acidophil and basophil cells in the anterior pituitary gland of the Menoprogen-fed rats versus healthy normal rats. Moreover, the cellular morphogenesis was in a healthy state for the Menoprogen-fed rats. Menoprogen significantly increased the levels of serum E(2) and P but reduced FSH and LH levels. The electron microscopic analysis showed that Menoprogen significantly retarded apoptosis of the ovarian granulocytes of the rats. Further investigation of Menoprogen for the alternative treatment of menopausal symptoms is warranted.

Postmenopausal hormone therapy: new questions and the case for new clinical trials

Observational studies suggest that postmenopausal hormone therapy (HT) prevents coronary heart disease, whereas randomized clinical trials have not confirmed a cardioprotective effect. Although observational studies may have overestimated the coronary benefit conferred by postmenopausal hormone use, there are other plausible explanations for the apparent discrepancy between previous results and the less favorable findings from clinical trials such as the large Women's Health Initiative. There is now a critical mass of data to support the hypothesis that age or time since menopause may importantly influence the benefit-risk ratio associated with HT, especially with respect to cardiovascular outcomes, and that the method of administration, dose, and formulation of exogenous hormones may also be relevant. Although the weight of the evidence indicates that older women and those with subclinical or overt coronary heart disease should not take HT, estrogen remains the most effective treatment currently available for vasomotor symptoms, and its effects on the development of coronary disease in newly postmenopausal women remain unclear. Moreover, effects of HT on quality of life and cognitive function in recently postmenopausal women merit further study. These unresolved clinical issues provide the rationale for the design of the Kronos Early Estrogen Prevention Study, a 5-year randomized trial that will evaluate the effectiveness of low-dose oral estrogen and transdermal estradiol in preventing progression of atherosclerosis in recently postmenopausal women.

Increased longevity in older users of postmenopausal estrogen therapy: the Leisure World Cohort Study

OBJECTIVE

To examine the effect of postmenopausal estrogen therapy (ET), including duration and recency of use, on all-cause mortality in older women.

DESIGN

As part of a prospective cohort study of residents of a California retirement community begun in the early 1980s, Leisure World Cohort women (median age, 73 y) completed a postal health survey including details on ET use and were followed up for 22 years (1981-2003). Age- and multivariate-adjusted risk ratios (RR) and 95% CIs were calculated using proportional hazard regression.

RESULTS

Of the 8,801 women, 6,626 died during follow-up (median age, 88 y). ET users had an age-adjusted mortality rate of 52.9 per 1,000 person-years compared with 56.5 among lifetime nonusers (RR = 0.91; 95% CI, 0.87-0.96). Risk of death decreased with both increasing duration of ET and decreasing years since last use (P for trend <0.001). The risk was lowest among long-term (> or =15 y) users (RR = 0.83; 95% CI, 0.74-0.93 for 15-19 y and RR = 0.87; 95% CI, 0.80-0.94 for 20+ y). For long-term users, the age-adjusted mortality rate was 50.4 per 1,000 person-years. Lower-dose users (< or =0.625 mg) had a slightly better survival rate than higher-dose users (RR = 0.84; 95% CI, 0.78-0.91 vs RR = 0.91; 95% CI, 0.83-0.97). Risk did not differ by route of administration (P = 0.56). Further adjustment for potential confounders had little effect on the observed RRs for ET.

CONCLUSION

Long-term ET is associated with lower all-cause mortality in older women.

Chronic Treatment with Physiological Doses of Estradiol Affects the GH-IGF-1 Axis and Fat Metabolism in Young and Middle-aged Ovariectomized Rats

Estrogen deficiency may be partly responsible for the metabolic syndrome and the condition may be reversible with hormone replacement therapy. However, after the heart and estrogen/progestin replacement study and the women's health initiative study the prospect of HRT on CVD has changed dramatically. As the pituitary and the liver are targets for estrogen action we assessed the effect of ovariectomy (OVX) and long-term (3 months) estradiol (E2) treatment by means of subcutaneously (s.c.) implanted silastic capsules on pituitary and liver function in young and middle-aged female rats. Our results demonstrate that triglyceride serum levels increased, whereas insulin-like growth factor-1 (IGF-1), high density lipoprotein cholesterol (HDL), and glucose levels decreased during the transition from young to middle-age. E2 treatment increased dose-independently growth hormone (GH) secretion. IGF-1 levels were increased upon OVX in middle-aged rats and the high dose of E2 decreased IGF-1 concentrations in both age groups. Cholesterol concentrations increased after OVX and were attenuated by E2 administration in middle-aged rats. Both, low density lipoprotein cholesterol (LDL) and HDL levels raised after castration and both parameters decreased in response to E2 in young and middle-aged rats. Glucose serum concentrations decreased after E2 treatment in all animals. Taken together, our results clearly demonstrate that the pituitary and the liver metabolism of middle-aged rats remain susceptible to the influence of OVX and E2 treatment.

Comparison of effects of pravastatin and hormone therapy on soluble P-selectin and platelet P-selectin expression in postmenopausal hypercholesterolemic women

OBJECTIVE

Recent trials have suggested an adverse early effect on cardiovascular risk of hormone therapy (HT) in postmenopausal women, an effect which could be due to an increase in arterial thrombosis via platelet activation. We examined the effect of HT on platelet surface expression of P-selectin, a marker of platelet activation, and plasma levels of soluble P-selectin, also believed to be a marker of platelet activation, and compared these effects with pravastatin, a drug proven to reduce cardiovascular events and reported to decrease both platelet and soluble P-selectin.

METHODS

Surface expression of platelet P-selectin, soluble P-selectin and fasting lipids were measured at baseline and 6 months in a randomized, double-blind study of postmenopausal hypercholesterolemic women comparing low-dose combined HT (1mg estradiol + 0.5 mg norethisterone acetate; n = 26) with pravastatin (n = 24).

RESULTS

After adjusting for baseline levels, HT and pravastatin produced similar reductions in soluble P-selectin (p < 0.0001 for both). The percentage of platelets expressing P-selectin was also reduced by pravastatin (p = 0.025), but there was a trend to an increase in platelet P-selectin expression with HT (p = 0.13), and a significant difference between pravastatin and HT in the changes in platelet P-selectin (p < 0.002). No relationship was evident between changes in soluble or platelet P-selectin and changes in lipids with either treatment.

CONCLUSIONS

In postmenopausal hypercholesterolemic women, both pravastatin and HT reduced soluble P-selectin levels, but only pravastatin reduced P-selectin expression on the surface of platelets. An implication of these findings is that the reduction in soluble P-selectin by HT may occur by a non-platelet related mechanism.

Coronary heart disease in menopausal women: implications of primary and secondary prevention trials of hormones

In direct contrast to the observational studies, both primary and secondary prevention trials of female reproductive hormones have found no benefit for coronary heart disease (CHD). Basic science studies have elucidated several mechanisms by which estrogen may improve coronary arterial physiology and prevent pathology, but have also found mechanisms by which estrogen might increase coagulation or inflammation, or might trigger coronary events in advanced lesions. Animal studies suggest that hormones may retard early atherosclerosis, while both animal studies and human angiographic trials are conclusive that hormones do not retard progression of raised lesions. Hormone use in the primary prevention observational studies would mostly have started at the age of menopause, in women whose arteries on average would be closer to normal than those of women in the clinical trials. One hypothesis worthy of further study is that estrogen may have a beneficial effect in normal or near-normal arteries, but the opposite effect in the presence of established atherosclerosis. However, at the average age of menopause, a substantial proportion of women has raised lesions, and a smaller proportion already has advanced lesions. Also, the apparent benefit of hormone use was found in secondary prevention observational studies, i.e., in women with compromised arteries. It is likely that uncorrected biases in the observational studies lead to an overestimation of any benefit of hormone use. On the other hand, endogenous estradiol may be responsible for the later onset of coronary disease in women compared to men; if so, then the appropriate test of the estrogen hypothesis would employ transdermal estradiol in a young population of menopausal women. Hormones are not indicated for the prevention of CHD, particularly in the light of the increased risk for stroke and venous thrombosis. Their use for other indications (menopausal symptoms, osteoporosis) needs to be tempered by the risk for cardiovascular disease (CVD).

Bridging advanced glycation end product, receptor for advanced glycation end product and nitric oxide with hormonal replacement/estrogen therapy in healthy versus diabetic postmenopausal women: A perspective

Cardiovascular diseases (CVD) are the most significant cause of death in postmenopausal women. The loss of estrogen biosynthesis with advanced age is suggested as one of the major causes of higher CVD in postmenopausal women. While some studies show beneficial effects of estrogen therapy (ET)/hormonal replacement therapy (HRT) in the cardiovascular system of healthy postmenopausal women, similar studies in diabetic counterparts contradict these findings. In particular, ET/HRT in diabetic postmenopausal women results in a seemingly detrimental effect on the cardiovascular system. In this review, the comparative role of estrogens is discussed in the context of CVD in both healthy and diabetic postmenopausal women in regard to the synthesis or expression of proinflammatory molecules like advanced glycation end products (AGEs), receptor for advanced glycation end products (RAGEs), inducible nitric oxide synthases (iNOS) and the anti-inflammatory endothelial nitric oxide synthases (eNOS). The interaction of AGE-RAGE signaling with molecular nitric oxide (NO) may determine the level of reactive oxygen species (ROS) and influence the overall redox status of the vascular microenvironment that may further determine the ultimate outcome of the effects of estrogens on the CVD in healthy versus diabetic women.

Menopausal Hormone Therapy

BACKGROUND

Although estrogen has been clinically available for more than 6 decades, women have been confused by different opinions regarding the risks and benefits of menopausal hormone therapy (HT), estrogen therapy (ET), and estrogen-progestin therapy (EPT). The publication of recent randomized controlled trials (RCTs), notably, the Heart and Estrogen Replacement Study (HERS), Women's Health Initiative (WHI), and Women's Health Initiative Memory Study (WHIMS), has intensified the risk versus benefit controversy and prompted this review.

OBJECTIVE

We provide a systematic, comprehensive, and critical review of selected literature that addresses the basic and clinical aspects of menopausal HT.

RESULTS

Solid, consistent evidence based on observational, epidemiologic, and randomized controlled trials underpins the efficacy of menopausal HT for its regulatory agency-approved indications: vasomotor symptoms, vulvovaginal atrophy symptoms, and osteoporosis-related fracture prevention. ET and EPT increase the risk for venous thromboembolism, although the absolute number of events and the risk are both small. Though there is a small increase in the number of breast cancers in women who have used menopausal HT for more than 10 years, the biological meaning of this observation (cause versus unmasking versus chance) is unresolved. Most evidence shows that menopausal HT does not affect breast cancer recurrence and that overall longevity is higher in breast cancer survivors who select menopausal HT. Strong basic science and clinical observational evidence show a benefit of menopausal HT in the cardiovascular and central nervous systems. Data from recent RCTs that included predominantly overweight women aged between 63 and 71 years have been reported to show more harm than benefit; the rush to generalize these studies to all women and all menopausal HT regimens is unjustified.

CONCLUSION

Menopausal HT improves vasomotor symptoms and vulvovaginal atrophy symptoms and prevents osteoporosis-related fracture. Menopausal HT increases the likelihood of venous thromboembolism, but other harms such as breast cancer require further controlled studies. A clinical benefit of menopausal HT for cardiovascular or central nervous system disease prevention is unproven. RCTs of menopausal HT in newly menopausal women, or in women less than 3 years from menopause, are urgently needed to investigate the prevention of cardiovascular and central nervous system aging diseases.

The absolute risk of recurrent myocardial infarction is similar amongst both sexes: MONICA Iceland Study 1981-1999

BACKGROUND

To do a gender comparison of absolute risk of recurrent myocardial infarction (MI).

DESIGN

Registration of all first and second MI amongst Icelandic males and females 1981-1999.

METHODS

The whole of Icelandic population, 40-74 years of age.

RESULTS

The mean recurrence rate (second attack) for men was 45.7/1000 MI survivors/year and for women 39.0/1000 per year. The male/female (M/F) ratio was 1.17, 95% confidence interval 1.00-1.37, P = 0.05 and did not change significantly with age. The M/F ratio for first MI in comparison was two to seven, lowest in the oldest group. The recurrence rate decreased significantly and similarly in both sexes during the observation period.

CONCLUSION

The absolute risk of MI is closely similar amongst both sexes and has decreased similarly suggesting that the same kind of secondary intervention is effective amongst both sexes in a general population.

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

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

Do lipid profiles of postmenopausal women under oral hormone replacement therapy remain stable or reveal a multiphasic course in time?

The object of this study was to compare the effects of oral conjugated estrogen (CEE) alone, CEE plus medroxyprogesterone acetate (MPA) and tibolone on lipid profiles, and investigate whether these effects change in time. Plasma lipid levels were studied for CEE (n = 49), CEE + MPA (n = 50) and tibolone (n = 51). Mean per cent changes at certain intervals were compared with their previous intervals for each therapy. Paired t-test was used for statistical analysis. CEE alone had raised high-density lipoprotein (HDL) and triglyceride levels and lowered total cholesterol and low-density lipoprotein (LDL) levels at the end of the 2-year study period. Addition of MPA to the CEE regimen weakened the effect on HDL and triglyceride, augmented the decrease in total cholesterol and did not affect LDL. The tibolone group revealed similar but more prominent effects in total cholesterol and LDL levels. HDL and triglyceride levels were significantly below baseline in the first 6 months, but HDL changes vanished and triglyceride levels remained decreased at the end of 2 years. These data did not support a correlation between lipid levels and the biphasic incidence of cardiac events that were observed in the Heart and Estrogen/progestin Replacement Study (HERS), but revealed period-dependent changes in the tibolone group.

HRT and heart disease: problems and prospects

The divergent findings of hormone replacement therapy (HRT) from observational and randomized clinical studies are summarized and reasons for the different results are postulated. Chronic use of HRT since menopause has no harmful effects on CHD event rate, while the initiation of therapy after a recent cardiovascular event causes an early increase in recurrent CHD events. Once endothelial dysfunction and atherosclerotic disease has developed, the starting of HRT promotes plaque instability, vascular inflammation and prothrombotic effects. The timing of HRT use since menopause is therefore crucial in the effectiveness and safety of HRT on the vascular system.

The Osteoporosis Prevention and Arterial effects of tiboLone (OPAL) study: design and baseline characteristics

The Osteoporosis Prevention and Arterial effects of tiboLone (OPAL) trial is a three-arm, randomized, placebo-controlled, double-blind study to determine the effect of tibolone 2.5 mg (Org OD 14) and continuous combined conjugated equine estrogens plus medroxyprogesterone acetate (0.625 mg/2.5 mg respectively) on progression of intima-media thickness of the carotid arteries and bone mineral density of the lumbar vertebrae and proximal femur in postmenopausal women. A total of 866 healthy postmenopausal women were recruited in six U.S. centers and five European centers. Duplicate carotid ultrasound examinations of the common carotid artery, the carotid bifurcation, and the internal carotid artery were performed at baseline. Single measurements of bone mineral density of the lumbar vertebrae and proximal femur were obtained at baseline. After randomization, ultrasound examinations were repeated every 6 months for 36 months following baseline, with a duplicate examination at the end of the study. Bone mineral density was measured every 12 months throughout the trial. The primary outcome is change in mean common carotid intima-media thickness (CIMT), defined as the average of the intima-media thickness measurements performed circumferentially at predefined angles for the near and far wall of 10-mm segments of the right and left distal common carotid arteries. Unique new features of the OPAL study are the specifically developed OPAL ultrasound protocol, yielding highly reproducible CIMT measurements, and the use of two experienced core laboratories for CIMT readings (one in the United States and one in Europe) with one common quality assurance and control program. The OPAL study is a large, placebo-controlled trial evaluating the effects of tibolone, as well as one of the first large randomized studies to determine the effects of continuous combined estrogen-progestin therapy on carotid atherosclerosis in healthy postmenopausal women. The OPAL study results are expected to complement other studies on atherosclerosis progression in healthy postmenopausal women.

The role of estrogen in cardiovascular disease

Cardiovascular disease is the number one cause of death among women, accounting for nearly 50% of female deaths. Statistics show that women on average develop cardiovascular disease 10 to 15 years later in life than men, and that the risk may increase after menopause. This observation has led to much speculation as to what physiological change(s) associated with menopause is responsible for the higher risk of atherosclerosis. Estrogen, with its potential as a cardioprotective agent and as an immunomodulator of the inflammatory response in atherosclerosis, has received the most attention. Understanding the mechanisms that lead to these differences may allow beneficial therapeutic intervention to enhance this effect in females and evoke this protection in males. This review will do the following: (1) characterize mechanisms of atherosclerosis, (2) explore the role of estrogen-replacement therapy, (3) define the effect of gender on inflammation, (4) compare and contrast the effects of estrogen and testosterone on endothelial functional, and (5) suggest mechanistic based therapeutic opportunities.

[Hormonal replacement therapy and cardiovascular risk: contra-indication or non-indication?]

In the field of cardiovascular risk and treatment of menopause, only one instruction can be currently given to the prescribers: caution. Since the publication of heart and estrogen/progestin replacement study, the dogma of the cardioprotection induced by hormonal replacement therapy began to crumble. This paradigm had set up with observational studies, which for the majority had neglected in their retrospective analysis the socio-economic factor. Since shock caused by HERS, nine randomized studies are accumulated. All are negative, except for EPAT. At present, all confirms the prophetic recommendation of J.E. Rossow, in 1996: "Putting the brakes on the bandwagon". The last guidelines formally prohibit HRT in coronary women or with the aim of primary prevention of chronic conditions in healthy postmenopausal women.

Estrogen therapy and risk of cardiovascular events among women with type 2 diabetes

OBJECTIVE

To evaluate the association between estrogen therapy and cardiovascular disease risk among women with type 2 diabetes.

RESEARCH DESIGN AND METHODS

A retrospective, case-cohort study was conducted among 6017 women aged 45-80 years with type 2 diabetes from 1 January 1986 to 31 December 1992 at the Group Health Cooperative in Washington state. Cardiovascular outcomes, including nonfatal myocardial infarction (n = 215), coronary revascularization (n = 253), and cardiovascular deaths (n = 229), were ascertained through 31 December 1998. Use of estrogen and progestin was derived from automated pharmacy records and modeled as a time-dependent variable. Median follow-up was 6.8 years. Multivariable-adjusted relative risk (RR) and 95% CI were calculated using Cox proportional hazard models for case-cohort analyses.

RESULTS

Current use of estrogen with (RR 0.43, 95% CI 0.22-0.85) or without (0.48, 0.30-0.78) progestin was associated with a decreased risk of cardiovascular events compared with never having used estrogen. Risk of cardiovascular events associated with a first episode of estrogen use (with or without progestin) of <25 months' duration (1.12, 0.49-2.54), first episode of use >or=25 months' duration (0.32, 0.06-1.70), and current use that was not the first episode of use (0.42, 0.42-0.67) indicated that recent initiation was not associated with an increase or decrease in risk.

CONCLUSIONS

These results show an association of estrogen therapy, with or without progestin, with decreased risk of cardiovascular events among women with type 2 diabetes. This association should be further investigated in large randomized, controlled trials.

Drug Therapy for Prevention of Recurrent Myocardial Infarction

OBJECTIVE

To provide an evidence-based overview of drug treatment for long-term secondary prevention of myocardial infarction (MI).

DATA SOURCES

We conducted searches of MEDLINE (1966-August 2002), the Cochrane Controlled Trial Register, and the reference list of each identified study.

STUDY SELECTION/DATA EXTRACTION

Trials and meta-analyses were included using the following criteria: (1) randomized trials, (2) description of identification procedure, inclusion criteria, outcome measures, and statistical methods, (3) confirmed MIs, (4) treatment continued for at least 1 month, and (5) all-cause mortality as primary outcome; other events as secondary outcomes. All authors interpreted the results from trials that met the inclusion criteria.

DATA SYNTHESIS

In randomized clinical trials, low-dose aspirin, high-intensity oral anticoagulants, beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, and statins decreased the risk of mortality and reinfarction after MI. Randomized clinical trials using calcium-channel blockers, antiarrhythmics, and hormone replacement therapy did not show benefits in patients with prior MI. Effects of the combined use of aspirin or oral anticoagulants with beta-blockers or ACE inhibitors plus statins must be derived from subgroup analysis of trials, but seem to be beneficial.

CONCLUSIONS

The use of at least aspirin or an oral anticoagulant, a beta-blocker or an ACE inhibitor, plus a statin should be incorporated in the treatment routine. Clopidogrel treatment might be an alternative to aspirin. Standard addition of a beta-blocker to ACE inhibitor-treated patients without reduced left-ventricular ejection fraction seems to be untimely.

Genetic variants of coagulation factor XIII, postmenopausal estrogen therapy, and risk of nonfatal myocardial infarction

We hypothesized that possession of either of 2 functional coagulation factor XIII polymorphisms, one within subunit A (Val34Leu) and one within subunit B (His95Arg), might modulate the prothrombotic effects of estrogen and help to explain the variation in incidence of arterial thrombotic events among postmenopausal women using hormone replacement therapy. In a population-based case-control study of 955 postmenopausal women, we assessed the associations of factor XIII genotypes and their interactions with estrogen therapy on risk of nonfatal myocardial infarction (MI). The presence of the factor XIIIA Leu34 allele was associated with a reduced risk of MI (odds ratio [OR] = 0.70, 95% confidence interval [95% CI] = 0.51-0.95). The presence of the factor XIIIB Arg95 allele had little association with MI risk. Neither factor XIII polymorphism alone significantly modified the association between the risk of MI and current estrogen use. In exploratory analyses, however, there was a significant factor XIII subunit gene-gene interaction. Compared to women homozygous for both common factor XIII alleles, the Arg95 variant was associated with a reduced risk of MI in the presence of the Leu34 variant (OR = 0.36, 95% CI = 0.17-0.75) but not in the absence of the Leu34 variant (OR = 1.11, 95% CI = 0.69-1.79). Moreover, among women who had at least 2 copies of the variant factor XIII alleles and were current estrogen users, the risk of MI was reduced by 70% relative to estrogen nonusers with fewer than 2 factor XIII variant alleles (P value for interaction =.03). If confirmed, these findings may permit a better assessment of the cardiovascular risks and benefits associated with postmenopausal estrogen therapy.

Hormone Replacement Therapy for Primary and Secondary Prevention of Heart Disease

Cardiovascular disease is the leading cause of death in women. In pooled analysis, observational studies have shown a 50% reduction in death and myocardial infarction among users of hormone replacement therapy (HRT) for the primary and secondary prevention of cardiovascular disease. The first randomized trial of HRT for secondary prevention of heart disease found no benefit to therapy (Heart and Estrogen/progestin Replacement Study ). Even after 6.8 years of follow-up, there was still no cardiovascular benefit from the use of HRT (HERS II). HRT was associated with a 50% increased risk of heart attacks within the first year as well as an increased risk of deep venous thrombosis (DVT) and pulmonary embolism (PE) (relative risk 2.89) and gallbladder disease (RR 1.38). The Estrogen Replacement and Atherosclerosis trial found no evidence that HRT slowed the progression of subclinical angiographic disease either. This was despite a favorable effect on high-density lipoprotein and low-density lipoprotein. The first randomized trial of HRT for the primary prevention of heart disease found no overall benefit (Women's Health Initiative). The combination of estrogen and progestin resulted in a 29% increase in heart attacks, 41% increase in stroke, a doubling of thrombotic events (DVT and PE), as well as a 26% increase in breast cancer. The risk for thrombotic events was greatest in the first year whereas the risk of breast cancer increased progressively with duration of therapy. HRT is no longer recommended for the primary or secondary prevention of cardiovascular disease or stroke. It may still be considered for short-term relief of menopausal symptoms in women without high-risk conditions, but alternatives exist.

Selective modulation of postmenopausal women: cutting the Gordian knot of hormone replacement therapy with breast carcinoma

BACKGROUND

Hormone replacement therapy (HRT) has proven and presumable benefits for women desiring postmenopausal health preservation. Among HRT-associated risks, the fear of breast carcinoma intimidates women and physicians contemplating hormonal treatment and limits long-term compliance. Identifying effective alternative medications that are not associated with breast carcinoma or that even may prevent its development would be a major advance.

METHODS

This article discusses the clinical perspective of HRT and selective estrogen receptor modulators (SERMs) in light of the molecular and cellular mechanisms of estrogen and progesterone action on the breast. Emphasis is placed on the potential of selective receptor modulation as the future of postmenopausal treatment.

RESULTS

Current epidemiologic evidence suggests that HRT is associated with a small but substantial increase in the risk of breast carcinoma, and combined estrogen-progesterone regimens further increase this hazard. Ample biologic data support this clinical association and propose multiple molecular mechanisms for the effects of estrogen and progesterone on breast cells. SERMs are a novel class of drugs that demonstrate estrogen agonistic and antagonistic actions in a tissue specific manner. SERMs act by binding the estrogen receptor and selectively modulating its effect on gene transcription at target tissues.

CONCLUSIONS

SERMs offer an alternative to HRT that can successfully circumvent the intimidating side-effect of breast carcinoma. Further insight into the molecular mechanisms of SERM action may enable the development of agents with improved target-tissue selectivity. Identifying selective modulators with unique pharmacologic properties would facilitate the creation of individualized treatment for the postmenopausal woman according to her particular predisposition for menopause-related morbidities and her overall clinical profile.

Oestrogen therapy for prevention of reinfarction in postmenopausal women: a randomised placebo controlled trial

BACKGROUND

Results of observational studies suggest that hormone replacement therapy (HRT) could reduce the risk of coronary heart disease (CHD), but those of randomised trials do not indicate a lower risk in women who use oestrogen plus progestagen. The aim of this study was to ascertain whether or not unopposed oestrogen reduces the risk of further cardiac events in postmenopausal women who survive a first myocardial infarction.

METHODS

The study was a randomised, blinded, placebo controlled, secondary prevention trial of postmenopausal women, age 50-69 years (n=1017) who had survived a first myocardial infarction. Individuals were recruited from 35 hospitals in England and Wales. Women received either one tablet of oestradiol valerate (2 mg; n=513) or placebo (n=504), daily for 2 years. Primary outcomes were reinfarction or cardiac death, and all-cause mortality. Analyses were by intention-to-treat. Secondary outcomes were uterine bleeding, endometrial cancer, stroke or other embolic events, and fractures.

FINDINGS

Frequency of reinfarction or cardiac death did not differ between treatment groups at 24 months (rate ratio 0.99, 95% CI 0.70-1.41, p=0.97). Similarly, the reduction in all-cause mortality between those who took oestrogen and those on placebo was not significant (0.79, 0.50-1.27, p=0.34). The relative risk of any death (0.56, 0.23-1.33) and cardiac death (0.33, 0.11-1.01) was lowest at 3 months post-recruitment.

INTERPRETATION

Oestradiol valerate does not reduce the overall risk of further cardiac events in postmenopausal women who have survived a myocardial infarction.

Evaluating participants' use of a hormone replacement therapy decision-making intervention

BACKGROUND

Associations between optimal use of a tailored decision-aid and levels of accuracy of perceived breast cancer risk, confidence in decision-making, and satisfaction with decisions about HRT were evaluated in a randomized intervention trial with a community sample of women aged 45-54.

METHODS

Data are from 289 women randomized to receive a computer-tailored three-step decision-aid.

RESULTS

Forty-seven percent of participants reported optimal use of the intervention materials. African American women and those with low confidence in decision-making were less likely to use the intervention optimally than white women and those with higher confidence (P<0.05). Optimal use of the decision-aid was associated with increased accuracy of perceived risk and confidence to make a decision.

DISCUSSION

When used optimally, self-directed decision-aids can improve women's ability to make decisions about HRT. Additional refinement of these aids is needed. For some subgroups of women, adjuncts such as telephone counseling also might be considered.

Hormone replacement therapy: short-term versus long-term use

Midwives manage health care of women throughout the life cycle including prescribing hormone replacement therapy (HRT). This article presents a history of research on the use of HRT, as well as risks and benefits. Older research on the effects of HRT on heart disease, osteoporosis, and breast cancer is included. The results and recommendations of the Women's Health Initiative are examined.

Pathophysiology and treatment of hot flashes

Hot flashes affect about three fourths of postmenopausal women and are one of the most common health problems in this demographic group. Dysfunction of central thermoregulatory centers caused by changes in estrogen levels at the time of menopause has long been postulated to be the cause of hot flashes. Treatment should begin with a careful patient history, with specific attention to the frequency and severity of hot flashes and their effect on the individual's function. For mild symptoms that do not interfere with sleep or daily function, behavioral changes in conjunction with vitamin E (800 IU/d) use is a reasonable initial approach. For more severe symptoms, the next step is to determine whether there is a contraindication or a personal reservation to estrogen replacement therapy. For women who are able and willing to use estrogen, it will successfully relieve symptoms by about 80% to 90%. In patients with a history of breast or uterine cancer, treatment with the progestational agent megesterol acetate appears to be a safe alternative that also decreases hot flashes by approximately 80%. For women unwilling or unable to use hormone therapy, one of the newer antidepressant agents can be prescribed. Venlafaxine decreases hot flashes by about 60%. Gabapentin is another drug that appears promising as therapy for women unable or unwilling to use estrogen, and the results of ongoing trials to determine its efficacy are eagerly awaited. The use of clonidine, methyldopa, and belladonna should be discouraged because of their modest efficacy and adverse effects.

Hormone replacement therapy and its relationship to lipid and glucose metabolism in diabetic and nondiabetic postmenopausal women: results from the Third National Health and Nutrition Examination Survey (NHANES III)

OBJECTIVE

Among postmenopausal women, those with diabetes experience more cardiovascular diseases than those without diabetes. We examine the relationship of hormone replacement therapy (HRT) with indicators of lipid and glucose metabolism using a national sample of diabetic and nondiabetic postmenopausal women.

RESEARCH DESIGN AND METHODS

We used data from the Third National Health and Nutrition Examination Survey, conducted from 1988 to 1994. A total of 2,786 postmenopausal women aged 40-74 years participated in an oral glucose tolerance test, had blood drawn for lipid assessment, and responded to HRT questions.

RESULTS

Our results show that postmenopausal women with diabetes had increased dyslipidemia compared with nondiabetic women. Among diabetic women, current users of HRT had significant different lipid and glucose control levels than never users of HRT for the following variables: total cholesterol (225 vs. 241 mg/dl), non-HDL (169 vs. 188 mg/dl), apoA (171 vs. 147 mg/dl), fibrinogen (306 vs. 342 mg/dl), glucose (112 vs. 154 mg/dl), insulin (16.81 vs. 22.6 uU/ml), and GHb (6.03 vs. 7.13 mg/dl).

CONCLUSIONS

Diabetic and nondiabetic postmenopausal women currently taking HRT had better lipoprotein profile than never or previous users of HRT. Diabetic women currently taking HRT had better glycemic control than never or previous users of HRT.

Risk factors indicating recurrent myocardial infarction after recovery from acute myocardial infarction

Little is known of the risk factors of recurrent myocardial infarction (MI) among Japanese patients who have survived their first MI. The risk factors for the second MI were studied in 808 of 1,042 consecutive patients who recovered from an acute MI in Iwakuni National Hospital. Multivariate logistic regression analysis revealed that only 3 of 21 variables measured were closely related with the recurrence of MI during a follow-up period of 3.2 +/- 4.3 years: (1) transient atrial fibrillation (relative risk (RR) 3.16), (2) previous cerebrovascular accident (RR 3.05), and (3) dyslipidemia (RR 2.19). Of the parameters of dyslipidemia, a low ratio of high-density lipoprotein-cholesterol (HDL-C) to low-density lipoprotein-cholesterol (LDL-C) alone indicated subsequent MI. None of age, gender, location of the infarction, hypertension, diabetes mellitus, pulmonary congestion (Killip's class > or = 2), peak serum creatine kinase activity, serum total-cholesterol, HDL- and LDL-cholesterol levels, nor smoking habit on admission was a statistically significant predictor for the second MI. The result suggests that more intensive treatment is needed for patients with the 3 risk factors.

Postmenopausal hormone replacement therapy and atherosclerosis

The role of postmenopausal hormone replacement therapy (HRT) in the prevention of cardiovascular disease (CVD) has evolved since estrogen was first proposed to be vasoprotective. The discovery of novel molecular signaling pathways involving the estrogen receptor in vascular cells and the elucidation of numerous biologic mechanisms have suggested that HRT may exert its potentially beneficial or adverse cardiovascular effects through multiple mechanisms. Estrogen has genomic, as well as rapid nongenomic, effects that alter vasodilation, coagulation, inflammation, and the vascular injury response, some of which may have potentially beneficial or adverse cardiovascular consequences. Current guidelines do not support the use of HRT in the secondary prevention of CVD, and recent results of primary prevention trials show evidence of increased early cardiovascular risk and no overall health benefit with combination estrogen-progestin treatment. The role of estrogen alone in the primary prevention of CVD awaits the results of ongoing trials. The key to the use of estrogen replacement therapy for the prevention of CVD may be to target therapy before atherosclerosis is evident, and to identify women with genetic susceptibility who may be at increased risk for an adverse outcome associated with therapy.

Hormone therapy and the cardiovascular system

The cardiovascular effects of female sex steroids have many faces and are very complex. To make this situation even more complicated different disease situations, different target organs and different therapeutic regimens may exhibit different effects of estrogens and progestines. Furthermore, the interpretation of population studies may be problematic by itself, in view of so many confounders and biases involved and methodological flaws that sometimes are discovered only post-hoc. It seems, therefore, that in such a complicated situation making definite conclusions and guidelines is almost an impossible task. My suggestion to clinicians is to try and follow the main stream of clinical data, looking at the general picture rather than the small details, and try to individualize therapy in order to maximize the benefits and minimize the adverse reactions and risks. This article discusses the current knowledge on hormone replacement therapy (HRT) and the cardiovascular system. It is not an overview, because my intention was not to pump in as much data as possible. Rather, the article presents current ideas and trends in this field to be used by people who practice menopause medicine for their own clinical decisions.

The metabolic syndrome in long-term cancer survivors, an important target for secondary preventive measures

With increasing numbers of cancer survivors, attention has been drawn to long-term complications of curative cancer treatment, including a range of metabolic disorders. These metabolic disorders often resemble the components of the so-called metabolic syndrome, or syndrome X, which is an important risk factor for the development of cardiovascular disease. The mechanisms behind the development of metabolic disorders in cancer survivors have not been fully elucidated. However, association studies in the general population have demonstrated correlations between the components of the metabolic syndrome on the one hand and hormonal deficiencies, hypomagnesaemia, and endothelial dysfunction on the other. These latter disorders are regularly reported following curative cancer treatment and could, therefore, be important aetiologic factors in the development of the metabolic syndrome in cancer survivors. This review discusses data on the associations between the metabolic syndrome and treatment-related complications in cancer survivors and possibilities for preventive measures.

Effects of hormone replacement therapy on blood platelets

BACKGROUND

Hormone replacement therapy (HRT) increases the risk of cardiovascular morbidity in postmenopausal women under certain circumstances. Part of this effect may be the result of the influence of HRT on blood platelets. We studied the effect of short-term oral hormone replacement therapy (unopposed oestradiol or sequentially combined oestradiol and trimegestone or dydrogesterone) on platelet activation parameters in healthy postmenopausal women.

DESIGN

We designed a prospective, randomised, placebo-controlled 12-week study. Sixty healthy, normotensive, nonhysterectomised, postmenopausal women received daily micronised oestradiol (E2) 2 mg (n = 16), or 2 mg E2 daily sequentially combined with either trimegestone 0.5 mg daily (n = 14) or dydrogesterone 10 mg daily (n = 14), or placebo (n = 16). Data on platelet activation were collected at baseline and after 12 weeks of treatment using flow cytometry.

RESULTS

Twelve weeks of treatment with combined HRT was associated with an increase in platelet activation parameters P-selectin and glycoprotein 53 (by 17% and 14%, respectively, P = 0.04 vs. the placebo group for both comparisons), suggesting alpha granule and lysosome degranulation. E2 replacement therapy was associated with an increase in P-selectin labelling by 22% (P = 0.04 vs. the placebo group).

CONCLUSION

Short-term treatment with oestradiol or combined HRT increases the amount of circulating activated platelets as measured by flow cytometry. This could be a mechanism by which short-term HRT might increase the risk of thrombosis.

Factor V Leiden, hormone replacement therapy, and risk of venous thromboembolic events in women with coronary disease

Oral contraceptive use in women with factor V Leiden is associated with increased rates of venous thromboembolic events (VTEs). However, the effects of hormone replacement therapy (HRT) in postmenopausal women with factor V Leiden are not known. A nested case-control study was conducted among women with established coronary disease enrolled in 2 randomized clinical trials of HRT, the Heart and Estrogen/Progestin Replacement Study (HERS) and the Estrogen Replacement and Atherosclerosis (ERA) trial. The Leiden mutation was present in 8 (16.7%) of 48 cases with VTE compared with only 7 (6.3%) of 112 controls (odds ratio [OR](Leiden) 3.3, 95% CI 1.1 to 9.8; P=0.03). In women without the factor V Leiden mutation, risk associated with HRT use was significantly increased (OR(HRT) 3.7, 95% CI 1.4 to 9.4; P<0.01). On the other hand, in women with the factor V Leiden mutation, the estimated risk associated with HRT was increased nearly 6-fold, although the CIs were wide and included unity (OR(HRT) 5.7, 95% CI 0.6 to 53.9; P=0.13). The OR for women with the Leiden mutation who were also assigned to HRT compared with wild-type women assigned to placebo was 14.1 (95% CI 2.7 to 72.4, P=0.0015). In women with the factor V Leiden mutation who were treated with HRT, the estimated absolute incidence of VTE was 15.4 of 1000 per year compared with 2.0 of 1000 per year in women without the mutation who were taking a placebo (P=0.0015). On the basis of these data, in women with coronary disease, the estimated number needed to screen for factor V Leiden to avoid an HRT-associated VTE during 5 years of treatment is 376. If factor V Leiden genotyping becomes less expensive, it could be cost effective to screen for the presence of the mutation before instituting HRT in women with coronary disease.

Update on cardiovascular disease in post-menopausal women

Cardiovascular disease (CVD), and in particular coronary artery heart disease (CAHD), is the leading cause of morbidity and mortality in women. Until recently, most of our knowledge about the pathophysiology of CVD in women - and, subsequently, management guidelines - were based on studies conducted mostly in men. While similar mechanisms operate to induce CVD in women and men, gender-related differences exist in the anatomy and physiology of the myocardium, and sex hormones modify the course of disease in women. Women, more than men, have their initial manifestation of CAHD as angina pectoris; are likely to be referred for diagnostic tests at a more advanced stage of disease, and are less likely than men to have corrective invasive procedures. The overall morbidity and mortality following the initial ischaemic heart event is worse in women, and the case fatality rate is greater in women than in men. Also, the relative impact of impaired vasoreactivity of the coronary artery, increased viscosity of the blood and dysregulation of automaticity and arrhythmia, is greater in women than in men. The most effective means of decreasing the impact of CVD on women's health is by an active approach from childhood to proper principles of healthcare in order to modify the contribution of specific risk factors. The latter include obesity, abnormal plasma lipid profile, hypertension, diabetes mellitus, cigarette smoking, sedentary lifestyle, increased blood viscosity, augmented platelet aggregability, stress and autonomic imbalance. The use of lipid-lowering drugs has not been adequately studied in women but reports from studies conducted mostly in men do predict an advantage also to women. Oestrogen deficiency after spontaneous or medically induced menopause is an important risk factor for CVD and CAHD. Observational and mechanistic data suggest a role for oestrogen replacement after menopause for primary, and possibly secondary, prevention of CVD. However, two recent prospective trials suggest that treatment de novo with hormone replacement of older post-menopausal women after an acute coronary event may not confer cardiovascular protection and may increase the risk of thromboembolic disease. Results of ongoing long-term studies may determine the beneficial role of hormone replacement versus potential risks involved with this treatment.

Coronary Heart Disease in Women: Hormone Replacement Therapy

For both primary and secondary prevention of coronary heart disease (CHD), it is prudent to use strategies that are of proven benefit and that do not harm patients. In all women, these strategies include lifestyle approaches such as smoking avoidance, proper nutrition, and regular exercise. Lipid-lowering and blood pressure control with pharmacotherapy are indicated in women who do not meet target lipid or blood pressure levels with lifestyle interventions. For women with CHD, aspirin, beta-blockers, and angiotensin-converting enzyme inhibitors should be considered. Widespread under-use of established preventive therapies has been documented in women. These interventions should be emphasized in clinical practice. For secondary prevention of CHD in women, the American Heart Association (AHA) recommends against initiating hormone replacement therapy (HRT) based on studies that have shown no benefit and early harm. For patients with CHD already on HRT, the decision to continue or stop HRT should be based on established noncoronary benefits and risks and patient preference. There are insufficient data to suggest that HRT should be initiated for the sole purpose of primary prevention of CHD. Because the new AHA guidelines recommend placing significant weight on the noncardiac benefits and risks of HRT, it is important to become familiar with these noncardiac effects. It is also important to understand the evidence supporting the AHA's decision to recommend placing relatively less weight on the cardiac effects of HRT.

Estradiol-intranasal: a review of its use in the management of menopause

Estradiol-intranasal is a nasal spray formulation containing an aqueous solution of 17beta-estradiol that has a unique pulse-like pharmacokinetic profile. In a well designed, placebo-controlled trial estradiol-intranasal 200 to 400 microg/day significantly reduced the incidence and severity of climacteric symptoms in women with moderate to severe menopausal symptoms after 4 and 12 weeks' treatment. The efficacy of estradiol-intranasal 300 microg/day was similar to that of oral estradiol 2 mg/day in this and another double-blind placebo-controlled trial. This equivalent efficacy was maintained in a subgroup of women with initially severe symptoms, and in smokers. Reductions in the incidence of atrophic vaginal mucosa and genitourinary symptoms and increases in the karyopyknotic index achieved with estradiol-intranasal 300 microg/day were also similar to those observed with oral estradiol 2 mg/day. Assessments of the effects of estradiol-intranasal on the complications of menopause (increased risk of cardiovascular disease and osteoporosis) are ongoing; however, estradiol-intranasal (sequentially combined with a progestogen) produced significant beneficial effects on some lipid parameters and on markers of bone resorption and formation, and bone mineral density in postmenopausal women. Estradiol-intranasal had no significant effects on serum levels of most of the assessed haemostatic factors, or on angiotensinogen or insulin levels. Estradiol-intranasal 100 to 600 microg/day was generally well tolerated in clinical trials and most adverse events were mild to moderate. The most commonly reported events were nasal symptoms and mastalgia. There was no evidence of endometrial hyperplasia with up to 1 year's treatment with estradiol-intranasal 300 microg/day combined with a progestogen. The incidence of mastalgia and withdrawal or breakthrough bleeding was lower with estradiol-intranasal 300 microg/day than with oral estradiol 2 mg/day (both administered with a progestogen) in one trial. In another trial, the incidence of mastalgia was lower with estradiol-intranasal 300 microg/day than with estradiol transdermal 50 microg (both administered with a progestogen). However, the overall incidence of adverse events was similar between the two treatments in this trial.

CONCLUSIONS

Estradiol-intranasal 200 to 400 microg/day (optimal initiating dose 300 microg/day) reduces the incidence and severity of menopausal climacteric symptoms and has a good tolerability profile. Thus, evidence to date suggests that estradiol-intranasal is a useful treatment option for menopausal symptoms.

Effect of estrogen on endothelial function and angiogenesis

Animal studies evaluating gender difference, the effects of gonadectomy and estrogen replacement and clinical studies in post-menopausal women with and without estrogen replacement therapy (ERT) proved that estrogen exerts significant benefits on the cardiovascular system. Since effects on the plasma lipoprotein profile is responsible for only approximately 25-40% of the cardiovascular protection exerted by estrogens, it is postulated that direct effects of estrogen on the vascular wall must play an important role. Indeed, experimental and clinical evidence accumulated over the past decade, and reviewed briefly here, indicate that at least a part of cardiovascular benefits of 17 beta-estradiol can be attributed to the direct effect of the ovarian sex steroid hormone on vascular endothelial cells. Maintenance and upregulation of endothelial nitric oxide production and suppression of EDCF generation by 17 beta-estradiol may play an important role in preventing or reversing endothelial dysfunction, associated with atherosclerosis, hypertension and other cardiovascular diseases. Stimulation of angiogenesis (especially collateral vessel formation in ischemic tissues) by the ovarian steroid hormone could be beneficial in coronary artery disease, peripheral vascular disease, cerebral ischemia (stroke) and congestive heart failure. Despite these indisputable beneficial effects, several key questions remain to be answered in the future, including the better understanding of the apparently opposite effects of estrogen on prevention of cardiovascular disease vs. treatment of existing disease.

Hormone replacement therapy: the benefits in tailoring the regimen and dose

Despite the clear benefits of long-term hormone replacement therapy (HRT), the majority of patients tend to undergo short-term treatment. The cyclical bleedings induced by the sequential progestogen administration are often unacceptable namely in the elderly postmenopausal women. At the standard doses HRT preparations can also induce annoying hormone-related side effects, both in sequential and continuous combined regimens. Lower HRT schedules are reported to be highly effective in the relief of climacteric symptoms, inducing minimal endometrial stimulation with high rates of amenorrhea. Continuous administration of low doses of progestins is safe for endometrium protection and minimizes progestin-related side effects. Indeed, it has been demonstrated that low dose HRT can prevent the increase in bone turnover and the consequent bone loss in postmenopausal women. The choice of lower HRT dosages can also be useful for the number of potential disadvantages of standard HRT doses, mainly for long-term treatments. Low dose regimens should be considered as a starting dose to minimize the occurrence of side effects, improving compliance and, therefore, HRT effects on the prevention of long-term consequences of estrogen deprivation.