The mechanisms of thrombotic risk induced by hormone replacement therapy

Risk of cardiovascular events following intermittent and continuous androgen deprivation therapy in patients with nonmetastatic prostate cancer

BACKGROUND

Intermittent androgen deprivation therapy (iADT) alleviates some side effects of continuous (c) ADT in patients with prostate cancer (PC), but its relative impact on ADT-associated comorbidities is uncertain. We assessed real-world use of iADT and cADT and associated risk of cardiovascular and endocrine/metabolic events in patients with nonmetastatic (nm) PC.

METHODS

This retrospective longitudinal cohort study included patients with nmPC initiating systemic ADT with gonadotropin-releasing hormone agonists (goserelin, histrelin, leuprolide, and triptorelin) or antagonists (degarelix) in the US Surveillance, Epidemiology and End Results-Medicare database (2010-2017), who had ≥ 36 months of continuous insurance coverage, unless death occurred, and did not receive chemotherapy or next-generation hormonal therapies during follow-up (through 2019). Risk of major adverse cardiovascular events (MACE [myocardial infarction, stroke, cardiomyopathy/heart failure, pulmonary embolism, ischemic heart disease, all-cause mortality]) and endocrine/metabolic events (diabetes, hypercholesterolemia, bone fractures, and osteoporosis) were examined between cohorts. Inverse probability of treatment-weighted Cox regression models estimated adjusted hazard ratios (HRs) of the outcomes.

RESULTS

Of 10,655 eligible patients, 2,095 (19.7%) received iADT and 8,560 (80.3%) cADT. Median follow-up was 43.9 and 48.4 months and median ADT duration (excluding iADT gaps) was 22.0 and 13.5 months for the iADT and cADT cohorts, respectively. Patients receiving cADT had a lower risk of MACE vs. iADT (HR 0.90; 95% confidence interval [CI] 0.83-0.96). No difference in risk of endocrine/metabolic events was observed (HR 0.97; 95% CI 0.92-1.03). Subgroup analysis found that the difference in MACE was maintained in patients with a history of cardiovascular disease (HR 0.90; 95% CI 0.83-0.98) and eliminated in patients without (HR 0.94; 95% CI 0.82-1.08).

CONCLUSIONS

Patients with nmPC who received cADT had a lower risk of MACE and similar risk of endocrine/metabolic events vs. those who received iADT. Further research assessing both regimens is needed to inform treatment decisions.

Intermittent versus continuous androgen deprivation therapy for advanced prostate cancer

Androgen deprivation therapy (ADT) is still a mainstay of treatment for advanced prostate cancer. Continuous ADT causes considerable patient morbidity including sexual dysfunction, poor mood and physical capacity, changes in body composition and health-care-related costs. Intermittent ADT has been used as an approach to ADT monotherapy to limit morbidity by enabling cyclical recovery of serum testosterone levels. To date, a number of well-performed randomized controlled trials and meta-analyses have demonstrated statistically insignificant differences in oncological outcomes between intermittent and continuous ADT monotherapy. Sexual outcomes, morbidity profiles and cost-savings favour intermittent therapy in most randomized trials, but the benefit for clinical practice is unclear. Despite the growing body of evidence, the optimal administration regime for ADT has not been clearly established and incorporation of adjunctive upfront treatments such as chemotherapy and novel anti-androgen agents has further hampered progress. Recommendations by authoritative urological and oncological societies regarding the use of intermittent ADT are limited. The potential benefits of reduced morbidity for a particular patient must be considered in light of the possible oncological outcomes. Although the oncological changes associated with intermittent ADT are controversial, intermittent ADT does seem to provide symptomatic benefit in patients compared with continuous ADT. However, careful selection of suitable patients is crucial.

Mechanisms of Sex Disparities in Cardiovascular Function and Remodeling

Epidemiological studies demonstrate disparities between men and women in cardiovascular disease prevalence, clinical symptoms, treatments, and outcomes. Enrollment of women in clinical trials is lower than men, and experimental studies investigating molecular mechanisms and efficacy of certain therapeutics in cardiovascular disease have been primarily conducted in male animals. These practices bias data interpretation and limit the implication of research findings in female clinical populations. This review will focus on the biological origins of sex differences in cardiovascular physiology, health, and disease, with an emphasis on the sex hormones, estrogen and testosterone. First, we will briefly discuss epidemiological evidence of sex disparities in cardiovascular disease prevalence and clinical manifestation. Second, we will describe studies suggesting sexual dimorphism in normal cardiovascular function from fetal life to older age. Third, we will summarize and critically discuss the current literature regarding the molecular mechanisms underlying the effects of estrogens and androgens on cardiac and vascular physiology and the contribution of these hormones to sex differences in cardiovascular disease. Fourth, we will present cardiovascular disease risk factors that are positively associated with the female sex, and thus, contributing to increased cardiovascular risk in women. We conclude that inclusion of both men and women in the investigation of the role of estrogens and androgens in cardiovascular physiology will advance our understanding of the mechanisms underlying sex differences in cardiovascular disease. In addition, investigating the role of sex-specific factors in the development of cardiovascular disease will reduce sex and gender disparities in the treatment and diagnosis of cardiovascular disease. © 2019 American Physiological Society. Compr Physiol 9:375-411, 2019.

RETRACTED: In vivo and in vitro antithrombus activities of depolymerized holothurian polysaccharides

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of authors. The authors have recently found a serious mistake in Table 1 of the article, where the molecular ratio of different monosaccharides is inconsistent with their previously published work. This error flaws the paper and so the authors wish it to be retracted to avoid misunderstanding and misinterpretation of their research work. The authors apologise for any concern or confusion that might have resulted in publishing this article.

Sex-specific vitamin D effects on blood coagulation among overweight adults

BACKGROUND

Overweight adults are at increased risk for cardiovascular disease and vitamin D deficiency, whereas an important feature to vitamin D physiology is its sex dependence. The aim of this study was to examine whether vitamin D status improvement exerts a sexually dimorphic effect on serum proteins associated with cardiovascular risk among overweight adults.

MATERIALS AND METHODS

Unprocessed serum from age- and BMI-matched men (n = 26) and premenopausal women (n = 24) with vitamin D deficiency and after they achieved sufficiency through a 12-month nutritional intervention was analysed using our previously published depletion-free quantitative proteomics method. Key findings were verified with ELISA. Differentially expressed proteins were subjected to in silico bioinformatics assessment using principal component analysis, hierarchical clustering and Metacore^™ pathway analysis. All mass spectrometry proteomic data are available via ProteomeXchange (identifier: PXD003663).

RESULTS

A total of 282 proteins were differentially expressed after the intervention between men and women (P-value ≤ 0·05), in which the blood coagulation pathway was significantly enriched. In agreement with the proteomics findings, ELISA measurements showed vitamin K-dependent protein C, von Willebrand factor, fibrinogen gamma chain and multimerin-1 proteins, of relevance to blood coagulation, to be differentially affected (P-value ≤ 0·05) between sexes after vitamin D status correction.

CONCLUSIONS

This study identified novel protein-level molecular indicators on the sexually dimorphic effect of vitamin D status correction associated with blood coagulation among overweight adults. These sex-mediated vitamin D effects should be factored in the design and interpretation of vitamin D observational and interventional studies testing cardiometabolic outcomes.

Adverse Health Events Following Intermittent and Continuous Androgen Deprivation in Patients With Metastatic Prostate Cancer

IMPORTANCE

Although intermittent androgen-deprivation therapy (ADT) has not been associated with better overall survival in prostate cancer (PC), it has the potential for lower adverse effects. To our knowledge, the incidence of long-term adverse health events has not been reported.

OBJECTIVE

To examine long-term late events in elderly patients randomized to intermittent or continuous ADT to determine whether late cardiovascular and endocrine events would be lower in patients treated with intermittent ADT.

DESIGN, SETTING, AND PARTICIPANTS

This was a secondary analysis of a multicenter clinical trial using linkage between patient data from S9346, a randomized SWOG trial of intermittent vs continuous ADT in men with metastatic PC, and corresponding Medicare claims.

EXPOSURE

Intermittent or continuous ADT.

MAIN OUTCOMES AND MEASURES

The main outcome was to identify long-term adverse health events by treatment arm. Patients were classified as having an adverse health event if they had any hospital claim--or at least 2 physician or outpatient claims at least 30 days apart--for any of the following diagnoses: ischemic and thrombotic events, endocrine events, sexual dysfunction, dementia, and depression. To incorporate time from beginning of observation through evidence of an event, we determined the cumulative incidence of each event. Competing risks Cox regression was used, adjusting for covariates.

RESULTS

In total, 1134 eligible US-based male patients with metastatic PC were randomized to continuous vs intermittent ADT in the S9346 trial. A total of 636 of trial participants (56%) had at least 1 year of continuous Medicare parts A and B coverage and no health maintenance organization participation. The median age was 71.3 years. The most common long-term events were hypercholesterolemia (31%) and osteoporosis (19%). The 10-year cumulative incidence of ischemic and thrombotic events differed by arm; 24% for continuous and 33%for intermittent ADT (hazard ratio, 0.69; P = .02). There were no statistically significant differences by arm in any other adverse health events.

CONCLUSIONS AND RELEVANCE

Contrary to our hypothesis that intermittent ADT would reduce long-term health-related events compared with continuous ADT, we found that older men assigned to intermittent ADT had no apparent reduction in bone, endocrine, or cognitive events and an increased incidence of ischemic and thrombotic events.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00002651.

A meta-analysis of cardiovascular events in intermittent androgen-deprivation therapy versus continuous androgen-deprivation therapy for prostate cancer patients

BACKGROUND

Androgen-deprivation therapy (ADT) is the standard treatment for advanced and recurrent prostate cancer but it has been shown to cause adverse effects on the cardiovascular system. Intermittent androgen deprivation has been studied as an alternative therapy. To conduct a meta-analysis comparing the incidence of cardiovascular events in patients with prostate cancer receiving intermittent (IADT) versus continuous ADT (CADT).

METHODS

We searched Cochrane CENTRAL, PubMed/Medline, Embase, Web of Science, The National Cancer Institute Clinical Trials and The Clinical Trials Register of Trials Central, and Google Scholar from inception of each database through February 2016. References from published guidelines, reviews and other relevant articles were also considered. We selected randomized clinical trials comparing IADT versus CADT in patients with prostate cancer that reported data on cardiovascular events. Two reviewers performed the study selection, data abstraction and risk of bias assessment. We calculated risk ratios with the Mantel-Haenszel method, using random effect models. We assessed heterogeneity using I² index. The primary outcome was incidence of cardiovascular events. Secondary outcomes were thromboembolic events and cardiovascular-related mortality.

RESULTS

Out of 106 references, we included seven articles from six trials (4810 patients) published between 2009 and 2015. We observed no significant difference between intermittent versus continuous androgen deprivation with respect to cardiovascular events (risk ratio (RR): 0.95; confidence interval (CI) 95%=0.83-1.08; seven trials, 4810 patients) and thromboembolic events (RR: 1.05; CI 95%=0.85-1.30; three trials, 1816 patients). There was marginally significant difference with respect to cardiovascular-related mortality (RR: 0.85; CI 95%=0.71-1.00; five trials, 4170 patients).

CONCLUSIONS

Compared with CADT, IADT shows no difference in terms of cardiovascular events and thromboembolic events. However, there was an association between lower cardiovascular-related mortality and intermittent androgen deprivation.

Coronary Heart Disease in Postmenopausal Women with Type II Diabetes Mellitus and the Impact of Estrogen Replacement Therapy: A Narrative Review

Coronary heart disease is the main cause of death in postmenopausal women (PMW); moreover its mortality exceeds those for breast cancer in women at all ages. Type II diabetes mellitus is a major cardiovascular risk factor and there is some evidence that the risk conferred by diabetes is greater in women than in men. It was established that the deficiency of endogenous estrogens promotes the atherosclerosis process. However, the impact of estrogen replacement therapy (ERT) on cardiovascular prevention remains controversial. Some authors strongly recommend it, whereas others revealed a concerning trend toward harm. This review tries to underlines the different components of cardiovascular risk in diabetic PMW and to define the place of ERT.

How I manage venous thromboembolism risk in hospitalized medical patients

Venous thromboembolism is a significant cause of illness and death worldwide. Large bodies of evidence support the heightened risk status of hospitalized medical patients, and that prophylactic measures significantly reduce the risk of thrombosis, yet these patients often fail to receive adequate prophylactic therapy. This failure may be accounted for by a lack of awareness of the relevant indications, poorly designed implementation systems, and clinical concerns over the side effects of anticoagulant medications. This article briefly summarizes our understanding of the clinical factors relevant to the evaluation of venous thromboembolism risk in hospitalized medical patients. We describe our approach to the use of thromboprophylaxis, through which we aim to minimize the disease burden of this under-recognized and preventable pathology.

Arzoxifene versus raloxifene: effect on bone and safety parameters in postmenopausal women with osteoporosis

Arzoxifene increased bone mineral density and decreased bone turnover to a significantly greater extent than raloxifene. The hot flush incidence was lower with arzoxifene than raloxifene.

INTRODUCTION

To assess the effect of arzoxifene versus raloxifene on change in lumbar spine (LS) bone mineral density (BMD) in postmenopausal women with osteoporosis.

METHODS

In this 12-month study (NEXT trial), participants were randomly assigned to arzoxifene 20 mg/day (N = 158) or raloxifene 60 mg/day (N = 162). All received daily calcium and vitamin D. Change in LS BMD was assessed by DXA. Secondary objectives included assessment of femoral neck (FN) and total hip BMD, serum bone turnover markers, and safety.

RESULTS

Treatment groups were similar at baseline (mean age 63 years, mean LS BMD T-score -2.9). At 12 months, the increase in LS BMD with arzoxifene was greater than with raloxifene (+2.75% vs. +1.66%), as was FN and total hip BMD (P < 0.05). For LS and FN, this effect was also evident at 6 months. Arzoxifene reduced bone turnover to a greater extent than raloxifene at 3, 6, and 12 months (P < 0.05). The proportion of women reporting ≥ 1 adverse event did not differ between treatment groups, nor did vaginal bleeding. No cases of endometrial polyps, hyperplasia, or cancer were reported. Nasopharyngitis and bronchitis were reported more frequently with arzoxifene versus raloxifene (10.1% vs. 2.5%, and 5.1% vs. 0%, respectively) and new/worsening hot flushes were reported less frequently with arzoxifene (7.0% vs. 16.7%) (P < 0.05).

CONCLUSIONS

Arzoxifene increased BMD and suppressed bone turnover to a greater extent than raloxifene and resulted in a lower incidence of new/worsening hot flushes. Based on subsequent findings from a fracture outcome study, this difference did not translate into improved fracture efficacy.

Postmenopausal Hormone Therapy and Risk of Idiopathic Venous Thromboembolism

Objective— Oral estrogen therapy increases venous thromboembolism risk among postmenopausal women. Although recent data showed transdermal estrogens may be safe with respect to thrombotic risk, the impact of the route of estrogen administration and concomitant progestogens is not fully established.

Methods and Results— We used data from the E3N French prospective cohort of women born between 1925 and 1950 and biennially followed by questionnaires from 1990. Study population consisted of 80 308 postmenopausal women (average follow-up: 10.1 years) including 549 documented idiopathic first venous thromboembolism. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox proportional models. Compared to never-users, past-users of hormone therapy had no increased thrombotic risk (HR=1.1; 95% CI: 0.8 to 1.5). Oral not transdermal estrogens were associated with increased thrombotic risk (HR=1.7; 95% CI: 1.1 to 2.8 and HR=1.1; 95% CI: 0.8 to 1.8; homogeneity: P =0.01). The thrombotic risk significantly differed by concomitant progestogens type (homogeneity: P <0.01): there was no significant association with progesterone, pregnanes, and nortestosterones (HR=0.9; 95% CI: 0.6 to 1.5, HR=1.3; 95% CI: 0.9 to 2.0 and HR=1.4; 95% CI: 0.7 to 2.4). However, norpregnanes were associated with increased thrombotic risk (HR=1.8; 95% CI: 1.2 to 2.7).

Conclusions— In this large study, we found that route of estrogen administration and concomitant progestogens type are 2 important determinants of thrombotic risk among postmenopausal women using hormone therapy. Transdermal estrogens alone or combined with progesterone might be safe with respect to thrombotic risk.

Low-dose oral combination of 17β-estradiol and norethisterone acetate in postmenopausal women decreases factor VII, fibrinogen, antithrombin and plasminogen activator inhibitor-1

OBJECTIVE

Controversies still persist concerning hormone replacement therapy (HRT) and its effects upon blood coagulation and fibrinolysis. This study was carried out to evaluate possible effects of continuously administered low-dose 17beta-estradiol (E2) and norethisterone acetate (NETA) on coagulation and fibrinolytic factors.

METHODS

We conducted a randomized double-blind, placebo-controlled, 1-year study in 120 healthy postmenopausal women. The three groups consisted of a placebo group (n = 40), a group receiving oral continuous combined E2 1 mg and NETA 0.25 mg (n = 40) and a group receiving oral continuous combined E2 1 mg and NETA 0.5 mg (n = 40).

RESULTS

The two low doses of E2-NETA induced significantly lower plasma levels of factor VII, fibrinogen, antithrombin and plasminogen activator inhibitor-1 (PAI-1), compared with placebo treatmen

CONCLUSIONS

Low-dose E2 (1 mg) in combination with NETA resulted in favorable changes of factor VII activity and fibrinogen, compared with placebo. The lower plasma levels of PAI-1 may lead to increased fibrinolytic activity. These findings suggest a decreased risk of developing coronary heart disease. Antithrombin activity was also reduced, which may increase the risk of developing venous thromboembolism. The clinical significance of the lower levels of these factors remains to be clarified.

Hormone therapy and venous thromboembolism among postmenopausal women: impact of the route of estrogen administration and progestogens: the ESTHER study

BACKGROUND

Oral estrogen therapy increases the risk of venous thromboembolism (VTE) in postmenopausal women. Transdermal estrogen may be safer. However, currently available data have limited the ability to investigate the wide variety of types of progestogen.

METHODS AND RESULTS

We performed a multicenter case-control study of VTE among postmenopausal women 45 to 70 years of age between 1999 and 2005 in France. We recruited 271 consecutive cases with a first documented episode of idiopathic VTE (208 hospital cases, 63 outpatient cases) and 610 controls (426 hospital controls, 184 community controls) matched for center, age, and admission date. After adjustment for potential confounding factors, odds ratios (ORs) for VTE in current users of oral and transdermal estrogen compared with nonusers were 4.2 (95% CI, 1.5 to 11.6) and 0.9 (95% CI, 0.4 to 2.1), respectively. There was no significant association of VTE with micronized progesterone and pregnane derivatives (OR, 0.7; 95% CI, 0.3 to 1.9 and OR, 0.9; 95% CI, 0.4 to 2.3, respectively). In contrast, norpregnane derivatives were associated with a 4-fold-increased VTE risk (OR, 3.9; 95% CI, 1.5 to 10.0).

CONCLUSIONS

Oral but not transdermal estrogen is associated with an increased VTE risk. In addition, our data suggest that norpregnane derivatives may be thrombogenic, whereas micronized progesterone and pregnane derivatives appear safe with respect to thrombotic risk. If confirmed, these findings could benefit women in the management of their menopausal symptoms with respect to the VTE risk associated with oral estrogen and use of progestogens.

The pathway-selective estrogen receptor ligand WAY-169916 displays differential activity in ischemia-reperfusion injury models

We previously reported on the development of a pathway-selective estrogen receptor (ER) ligand, WAY-169916, that has ER-dependent antiinflammatory activity and is devoid of classic ER transcriptional activity. In the current study, WAY-169916 and 17beta-estradiol (17beta-E2) were evaluated for protective activity in models of cardiac ischemia-reperfusion injury. In rats subjected to cardiac ischemia-reperfusion injury by occlusion of the left coronary artery, infarct size relative to the area at risk in the left ventricle was significantly attenuated by a single dose of 17beta-E2 (20 microg/kg, SC), and WAY-169916 administered SC (10 mg/kg) or IV (1 mg/kg) during the ischemia phase. In isolated hearts perfused on a Langendorff apparatus and subjected to global ischemia and reperfusion, 17beta-E2 and WAY-169916 both had direct cardioprotective activity when perfused at 1 microM but their effects varied between different end points. Perfusion with 17beta-E2 only improved recovery of left ventricle-developed pressure. Perfusion with WAY-169916 attenuated the elevation in perfusion pressure, diastolic pressure, and release of creatine kinase after ischemia. In contrast to 17alpha-ethinylestradiol, WAY-169916 had no classic estrogen effects on uterine weight or total serum cholesterol in rats treated for 4 days. The data demonstrate that the pathway-selective ER ligand WAY-169916 displays differential activity in vivo on different cardiovascular end points.

Less Effect of Intranasal Than Oral Hormone Therapy on Factors Associated With Venous Thrombosis Risk in Healthy Postmenopausal Women

Objective— To compare the effects of intranasal and oral administration of 17β-estradiol (E 2 ) and norethisterone(acetate) [NET(A)] in healthy postmenopausal women on activated protein C (APC) resistance and other hemostatic parameters associated with venous thrombosis.

Methods and Results— In this 2-center, randomized, double-blind, 1-year trial, 90 postmenopausal women (56.6±4.7 years of age) received daily either an intranasal spray with 175 μg/275 μg E 2 /NET (n=47) or 1 mg/0.5 mg oral E 2 /NETA (n=43). Normalized APC sensitivity ratios (nAPCsr) were determined with a thrombin generation-based APC resistance test. After 1 year, the increase in nAPCsr was smaller in the intranasal than in the oral group: 11% (95% CI, 1% to 22%) versus 53% (95% CI, 37% to 72%). Overall, the decrease in antithrombin and increase in prothrombin fragment 1+2 (F1+2) were smaller and the decrease in free protein S larger in the intranasal compared with the oral group after 1 year. In both groups, the decreases in protein C and prothrombin, and the increase in d -dimer were similar.

Conclusion— Compared with oral E 2 /NETA therapy, intranasal administration of E 2 /NET had less effect on APC resistance and on a number of other parameters associated with venous thrombosis. This observation suggests the possibility of a lower venous thrombosis risk for intranasal E 2 /NET compared with oral therapy.

[Effects of transdermic estrogen therapy, isolated or in association with micronized progesterone, on clotting factors in overweight or normal postmenopausal women]

To evaluate HRT action over hemostasis we treated 45 postmenopausal women, divided in: Group 1 (N= 22, hysterectomized) and Group 2 (N= 23, with uterus), at the average age of 51.6 years and average BMI of 27.1 kg/m(2), with no significant difference in the base-line, with 17beta-oestradiol, 50 mcg/day, transdermic and continuous (group 1) associated to micronized progesterone 200 mg 12 days per month (group 2). The average of 2 samples of TAP, PTT, fibrinogen and platelet number was measured monthly during 3 months. For the total sample, there was a PTT shortening along treatment, from the second evaluation on (p= 0.006). Fibrinogen in Group 2 was significantly higher than in Group 1, from the second evaluation on (p= 0.0005). Patients with BMI > 25 presented a greater TAP shortening (p= 0.040) and a smaller fibrinogen drop (p= 0.033) than patients with BMI < 25. Prothrombotic effects predominated, especially in overweight women and in those who used progesterone.

Benefits and risks of sex hormone replacement in postmenopausal women

Because cardiovascular disease (CVD), which is far less common in young women than in men, but increases in prevalence in the postmenopausal years to that of men, estrogen repletion therapy (ERT) or combined hormone replacement therapy (HRT), has been widely used to protect against development of both CVD and osteoporosis, and possibly to delay or prevent cognitive loss or Alzheimer's disease (AD). To test the validity of favorable findings in many small-scale studies, and in clinical practice, a large-scale trial: the Women's Health Initiative (WHI) was undertaken by the National Institutes of Health (NIH), a trial that was prematurely ended because of increased CVD complications, despite some lessening of hip fractures. This paper suggests that the customary high intake of calcium (Ca)-advised to protect against osteoporosis, and the marginal magnesium (Mg) intake in the USA, might well be contributory to the adverse CV effects, that were all thromboembolic in nature. The procoagulant effect of estrogen is intensified by Ca; Mg-which counteracts many steps in the coagulation cascade and inhibits platelet aggregation and adhesion-is commonly consumed in sub-optimal amounts. The high American dietary Ca/Mg ratio might also be contributory to the WHI failure to confirm ERT's favorable mental effects. Discussed are mechanisms by which Mg enhances estrogen's central nervous system protective effects. Mg's improvement of cerebral blood flow, which improves brain metabolism, can also enhance removal of the beta amyloid peptide, accumulation of which is implicated in AD.

Differential effects of estrogens and progestins on the anticoagulant tissue factor pathway inhibitor in the rat

Oral contraceptives (OC) and postmenopausal hormone therapy (HT) modulate plasma levels of proteins that regulate blood coagulation. It remains unclear whether the progestin component contributes to these changes. The present study was designed to determine whether progestins modulate two essential plasma anticoagulants, antithrombin (AT) and tissue factor pathway inhibitor (TFPI), in an animal model. Ovariectomized rats were treated orally with three progestins, norethindrone acetate (NETA), trimegestone (TMG), or drospirenone (DSP), either alone or combined with 17alpha-ethyinylestradiol (EE). Plasma AT levels were unchanged. However, TFPI activity was reduced by EE alone (10-100 microg/kg/day) in a dose-dependent manner; NETA (3 or 10 mg/kg/day) reduced TFPI by approximately 40 or approximately 80%, respectively, while TMG and DSP had no effect. NETA and EE effects were blocked by co-administration of ICI-182,780, an estrogen receptor antagonist, suggesting that both responses were likely estrogen receptor-mediated. Reduced TFPI after NETA or EE treatment was not accompanied by changes in TFPI mRNA levels in tissues that express TFPI, but there was a positive correlation between plasma TFPI and total cholesterol. Sex hormone effects on TFPI in this model and as reported in women may help to shift the coagulation balance to a more prothrombotic state. Progestins such as TMG and DSP that lack estrogenic activity could potentially have an improved clinical profile.

Patients' and clinicians' attitudes after the Women's Health Initiative study

OBJECTIVE

To assess the effect of the publication of the Women's Health Initiative (WHI) study on patients' and physicians' attitudes in relation to hormone therapy (HT).

DESIGN

A survey focused on the degree of knowledge and on the reactions to the WHI study was administered to 600 women allocated in two groups according to their socioeconomic status, high (HSES) or low (LSES). Additionally, 283 physicians were surveyed to determine their attitudes regarding HT after the publication of the WHI study. The rates of HT prescription before and after publication of the study were compared.

RESULTS

Among patients, HT use and knowledge of the WHI study were less common among women of lower socioeconomic status (LSES 16.7% v HSES 47.3%, and LSES 15.7% v HSES 67.3%; P < 0.0001). Of the women in the LSES group who were HT users and had knowledge on the subject of the WHI study (n = 30), 56.7% contacted their physicians and 6.6% abandoned HT. These rates were similar for women in the HSES group. Among physicians, 97.2% of physicians referred to being aware of the WHI study, and 64.7% modified their clinical approach. The main changes were that 21.5% applied more rigorous risk/benefit assessment, 20.1% lowered hormone dosage, 18.8% decreased continuous-combined therapy use, 12.1% shortened the duration of HT, 7.7% abandoned medroxyprogesterone or conjugated estrogen use, and 5.0% increased the use of transdermal estrogens, tibolone, or other alternatives. As for prescriptions, after the publication of the WHI study, there was an 8.6% drop in the rate of HT prescriptions. This decrease was more pronounced for prescriptions based on conjugated equine estrogen and medroxyprogesterone acetate. In contrast, prescription of transdermal estrogens and tibolone increased 5.2% and 16%, respectively.

CONCLUSIONS

There was a significant change in physicians' and patients' attitudes toward HT after publication of the WHI study.

Raloxifene, conjugated oestrogen and endothelial function in postmenopausal women

OBJECTIVES

To study the long-term effects of raloxifene, a potential designer oestrogen, and oestrogen monotherapy on endothelial function in healthy postmenopausal women.

DESIGN

A 2-year double-blind, randomized and placebo-controlled study in an Academic Medical Center. Fifty-six hysterectomized but otherwise healthy postmenopausal women randomly received raloxifene hydrochloride 60 mg day-1 (n = 15) or 150 mg day-1 (n = 13), conjugated equine oestrogen (CEE) 0.625 mg day-1 (n = 15), or placebo (n = 13).

MAIN OUTCOME MEASURES

Endothelial function as estimated from brachial artery flow-mediated, endothelium-dependent vasodilation and nitroglycerine-induced endothelium-independent vasodilation, and plasma levels of the endothelium-derived regulatory proteins, von Willebrand factor (vWF) and endothelin (ET).

RESULTS

Raloxifene 60 mg did not significantly affect endothelial function. As compared with placebo, at 6 months of therapy, raloxifene 150 mg and CEE were associated with a mean increase in vWF of 25.5% point (95% CI 3.6-47.3) and 26.6% point (95% CI 6.9-46.3), respectively. At 24 months of therapy, raloxifene 150 mg was associated with a mean decrease in ET of 0.96 pg mL-1 (95% CI -1.57 to -0.36). Raloxifene nor CEE significantly affected endothelium-dependent and/or -independent vasodilation.

CONCLUSIONS

Our results suggest that long-term therapy with raloxifene or oral CEE does not affect endothelium-dependent vasodilation in healthy postmenopausal women. Raloxifene 150 mg day-1 might have both positive and negative effects on endothelium. The clinical significance of these findings remains to be investigated.