Hormone replacement therapy in healthy postmenopausal women: a randomized, placebo-controlled study of effects on coagulation and fibrinolytic factors

To clot, or not to clot: The dilemma of hormone treatment options for menopause

Untreated menopause may have serious health implications, but treatments can have dangerous side effects. We evaluate menopausal symptoms as well as available treatments -the routes of administration and their effect on blood coagulation. Menopausal females may experience hot flushes, vulva- and vaginal atrophy and osteoporosis. Many treatments are available to relieve these symptoms such as Conjugated Equine Estrogen and bioidentical hormones. The routes of administration include oral and transdermal. Hormones that are administered orally undergo a hepatic first pass metabolism. The by-products have a lower efficacy and possibly enhanced side effects. Furthermore, hormone treatments influence the coagulation cascade through coagulation factors or their regulators. Increased coagulation poses a risk for venous thromboembolism. Currently a definite conclusion on whether the side effects from hormone treatments exceed the risk of untreated menopause cannot be made. However, a more individualised approach to hormone treatments may be the most feasible solution to this dilemma.

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.

Hormone therapy and hemostasis among postmenopausal women: a review

OBJECTIVE

Postmenopausal hormone therapy (HT), which consists of exogenous estrogens with or without combined progestogens, remains the most effective treatment of climacteric symptoms. Depending on its characteristics, it may nevertheless increase the risk of venous thromboembolism, and its effects on hemostasis have been studied for several decades. The aim of this review was to summarize current knowledge on the effects of HT on hemostasis, taking into account the route of estrogen administration, the daily dose and chemical structure of estrogens, and the pharmacologic class of progestogens.

METHODS

Data from randomized controlled trials that included a control group (either placebo or no treatment) were selected, and analysis was conducted on different generations of biomarkers.

RESULTS

Overall, studies showed a hemostasis imbalance among oral estrogen users with a decrease in coagulation inhibitors and an increase in markers of activation coagulation, leading to global enhanced thrombin generation. By contrast, transdermal estrogen use was associated with less change in hemostasis variables and did not activate coagulation and fibrinolysis. No clear difference in HT effects on hemostasis was highlighted between daily doses of estrogens, between estrogen compounds, and between pharmacologic classes of progestogens.

CONCLUSIONS

Changes in hemostasis are in accordance with clinical results showing an increased thrombotic risk with oral--but not transdermal--estrogen use.

Ovariectomy differential influence on some hemostatic markers of mice and rats

Rodent ovariectomy is an experimental method to eliminate the main source of sexual steroids. This work explored for the first time the ovariectomy temporal changes induced in the hemostatic coagulation markers: prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin time (TT), and fibrinogen concentration (FIB) along with uterine weight on adult female CD1 mice and Wistar rats. Uterine weight (Uw) was assessed before ovariectomy (control), and 1, 3, 5, 7, 9, 16, and 21 days after surgery. PT, aPTT, TT and FIB were estimated the same days, using reported standard techniques. Ovariectomy decreased Uw, since day 1; and from day 10 to 21 reached the lowest values for both species. After day 1, mice hemostatic parameters changed (PT +10%, P<0.05; aPTT +53%, P<0.05; TT −24%, P<0.05; FIB +67%, P<0.05). Rats showed significant changes only in TT and FIB (TT −13%, P<0.001; FIB +65%, P<0.001). Neither mice PT, aPTT and TT, recovered control values after 21 days. In the rats from day 5 to 16 aPTT diminished (18–23%, P<0.05) recovering to control values on day 21, TT after 9 days and PT on day 16. In both species, FIB returned to its control values after 9 days. Ovariectomy differentially altered the PT hemostatic parameter of mice and rats indicating a non-equivalence among both species behaviour for experimental studies of blood coagulation.

Nanostructured transdermal hormone replacement therapy for relieving menopausal symptoms: a confocal Raman spectroscopy study

OBJECTIVE

To determine the safety and efficacy of a transdermal nanostructured formulation of progesterone (10%) combined with estriol (0.1%) + estradiol (0.25%) for relieving postmenopausal symptoms.

METHODS

A total of 66 postmenopausal Brazilian women with climacteric symptoms of natural menopause received transdermal nanostructured formulations of progesterone and estrogens in the forearm daily for 60 months to mimic the normal ovarian secretory pattern. Confocal Raman spectroscopy of hormones in skin layers was performed. Clinical parameters, serum concentrations of estradiol and follicle-stimulating hormone, blood pressure, BI-RADS classification from bilateral mammography, and symptomatic relief were compared between baseline and 60 months post-treatment. Clinicaltrials.gov: NCT02033512.

RESULTS

An improvement in climacteric symptoms was reported in 92.5% of women evaluated before and after 60 months of treatment. The serum concentrations of estradiol and follicle-stimulating hormone changed significantly (p<0.05) after treatment; the values of serum follicle-stimulating hormone decreased after 60 months from 82.04±4.9 to 57.12±4.1 IU/mL. A bilateral mammography assessment of the breasts revealed normal results in all women. No adverse health-related events were attributed to this hormone replacement therapy protocol.

CONCLUSION

The nanostructured formulation is safe and effective in re-establishing optimal serum levels of estradiol and follicle-stimulating hormone and relieving the symptoms of menopause. This transdermal hormone replacement therapy may alleviate climacteric symptoms in postmenopausal women.

Can von Willebrand disease be investigated on combined hormonal contraceptives?

STUDY OBJECTIVE

To review the medical literature and determine whether testing for von Willebrand disease can be performed in adolescents using combined hormonal contraceptives (CHC).

DESIGN

Literature review where Embase and Medline were searched using the key words "von Willebrand factor," "von Willebrand disease," "contraceptive agents," and "menorrhagia." Articles were included in the review if they were controlled trials comparing a current form of CHC versus a control group and testing for von Willebrand factor was performed and reported.

MAIN OUTCOME MEASURES

Impact of combined hormonal contraceptives on von Willebrand factor antigen. Secondary outcomes included effects on Factor VIII and von Willebrand factor activity known as the Ristocetin cofactor.

RESULTS

Seven articles met inclusion criteria. All seven assessed VWF Ag with CHC use; six of the seven demonstrated no change and one, Gevers Leuven, demonstrated a significant decrease after CHC use. Three studies measured Factor VIII and showed no significant change with use. One study by Kadir assessed the Ristocetin cofactor and also failed to demonstrate change on CHC.

CONCLUSION

From the literature it appears that adolescents, assessed for menorrhagia and already on combined hormonal contraceptives, can be tested for von Willebrand disease if this diagnosis is suspected by the physician. By allowing adolescents to remain on combined hormonal contraceptives during testing, one avoids the risk of recurrent and severe menorrhagia which could result in admission and transfusion.

The differential effect of estrogen, estrogen–progestin and tibolone on coagulation inhibitors in postmenopausal women

OBJECTIVES

Hormone therapy increases the risk of venous thromboembolism, possibly through a negative effect on coagulation inhibitors. The aim of the study was to assess the effect of conjugated equine estrogens alone or in combination with medroxyprogesterone acetate, low-dose 17beta-estradiol combined with norethisterone acetate and tibolone on inhibitors of coagulation.

METHODS

Two hundred and sixteen postmenopausal women received orally either conjugated equine estrogens 0.625 mg (CEE, n=24) or tibolone 2.5 mg (n=24) or CEE+medroxyprogesterone acetate 5 mg (CEE/MPA, n=34) or 17beta-estradiol 1 mg+norethisterone acetate 0.5 mg (E2/NETA, n=66) or no therapy (control, n=68) for 12 months. Plasma antithrombin, protein C and total protein S were measured at baseline and at 12 months.

RESULTS

CEE, CEE/MPA and E2/NETA treatment were associated with a significant decrease in antithrombin levels (CEE: baseline 235.6+/-47.6 mg/l, follow-up 221.3+/-48.3 mg/l, p=0.0001; CEE/MPA: baseline 251.1+/-38.6 mg/l, follow-up 225.0+/-42.6 mg/l, p=0.009; E2/NETA: baseline 257.1+/-59.4 mg/l, follow-up 227.1+/-50.4 mg/l, p=0.007; tibolone: baseline 252.6+/-62.4 mg/l, follow-up 261.9+/-59.1 mg/l, p=0.39). Protein C decreased significantly in the CEE and CEE/MPA groups (CEE: baseline 3.64+/-1.17 mg/l, follow-up 2.48+/-1.47 mg/l, p=0.004; CEE/MPA: baseline 3.24+/-1.23 mg/l, follow-up 2.61+/-1.38 mg/l, p=0.001; E2/NETA: baseline 3.24+/-1.10 mg/l, follow-up, 3.15+/-1.11 mg/l, p=0.08; tibolone: baseline 3.26+/-1.25 mg/l, follow-up 3.09+/-1.32 mg/l, p=0.37). Protein S decreased significantly only in the CEE/MPA group (CEE: baseline 19.4+/-2.76 mg/l, follow-up 18.0+/-2.45 mg/l, p=0.56; CEE/MPA: baseline 18.4+/-3.42 mg/l, follow-up 14.5+/-3.43 mg/l, p=0.005; E2/NETA: baseline 19.0+/-3.11 mg/l, follow-up 19.5+/-3.43 mg/l, p=0.18; tibolone: baseline 18.5+/-3.09 mg/l, follow-up 18.0+/-4.09 mg/l, p=0.32).

CONCLUSIONS

Estrogen and estrogen-progestin therapy are associated with a reduction in coagulation inhibitors, the extent of which depends on the regimen administered. Tibolone appears to have no effect on inhibitors of coagulation.

Lipid biomarkers, hormone therapy and the risk of venous thromboembolism in women

BACKGROUND

Published reports of a relationship between lipids and incident venous thromboembolism (VTE) are conflicting.

OBJECTIVES

To clarify the relationship between lipids and VTE risk in healthy women, including potential effect modification by hormone therapy (HT).

PATIENTS/METHODS

Among 27 081 initially healthy women followed prospectively for incident VTE, we measured a full panel of lipid biomarkers, including total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides and apolipoproteins A-I (apo A-I) and B(100).

RESULTS

During a median follow-up of 11.4 years, VTE occurred in 355 women. We observed no relationship between any of the lipids and VTE risk. However, when unprovoked VTE was considered separately (n=161), both HDL-C and apo A-I were positively associated with risk. Fully adjusted hazard ratios (HR) and 95% confidence intervals (CI) for extreme tertiles of HDL-C and apo A-I were 1.75 (1.13-2.73) and 1.70 (1.10-2.62), respectively. After stratifying by HT use, this relationship was present only among HT users; the HRs for unprovoked VTE for extreme tertiles of HDL-C and apo A-I were 3.58 (1.69-7.58) and 2.88 (1.29-6.42) among users, but only 0.79 (0.39-1.62) and 0.89 (0.50-1.57) among non-users. The interactions were statistically significant (each Pinteraction<0.05).

CONCLUSIONS

We observed little evidence that lipid levels predict risk of incident VTE among non-users of HT. High levels of HDL-C and apo A-I associate with unprovoked VTE risk among HT users. This observation likely reflects prothrombotic effects of HT that are concomitant with HDL-C and apo A-I levels, rather than direct effects of those lipids.

Effect of estrogen-progestin hormonal replacement therapy on blood coagulation and fibrinolysis in postmenopausal women

OBJECTIVE

To evaluate antithrombin III (AT), thrombin (Fragment 1+2 [F1+2] and thrombin-antithrombin [TAT]) generation markers, as well as other coagulation parameters, such as prothrombin time, partial activated thromboplastin time, thrombin time, fibrinogen, euglobulin lysis time, and platelet count, in postmenopausal women after hormonal therapy.

STUDY DESIGN

Forty-five patients who received either 0.625 mg/day unopposed oral conjugated equine estrogen (CEE), 0.625 mg/day oral CEE plus medroxyprogesterone acetate (MP), or 50 microg/day transdermal 17beta-estradiol plus MP, were included. Tests were performed before (T0) and after 3 (T3), 6 (T6) and 12 (T12) months of treatment. AT was determined by an amidolytic method, whereas F1+2 and TAT complex were measured by ELISA.

RESULTS

There was a significant reduction in the AT level of patients who received oral CEE plus MP at T3. There was no AT reduction in patients taking either oral CEE alone or transdermal 17beta-estradiol plus MP. F1+2 increased in all patients, but it reached statistical significance only in patients receiving transdermal 17beta-estradiol MP at T3.

CONCLUSIONS

The CEE associated with MP treatment may reduce AT levels, whereas unopposed CEE or transdermal 17beta-estradiol plus MP does not change AT. These changes might not be clinically relevant in the general population; however, hormonal replacement therapy may increase the risk of thrombosis in women with congenital or acquired thrombophilia.

Pharmacologic Interventions for the Management of Critical Bleeding

Hospital pharmacists are often consulted for their knowledge about coagulation and therapeutic interventions for the management of critical bleeding. Many pharmacotherapies are available for this purpose, both systemic and topical, and others are in development. These agents and their mechanisms of action are reviewed, and perspectives are provided regarding their use in various clinical settings. Also provided are associated precautions to promote safe use. Current controversies surrounding pharmacotherapeutic agents used to control serious bleeding (e.g., in various types of surgery, trauma, obstetrics, and intracranial hemorrhage) are also discussed.

Changes in Hemostatic Variables Induced by Estrogen Replacement Therapy: Comparison of Transdermal and Oral Administration in a Crossover-Designed Study

AIM

The purpose of this study was to determine the changes of biochemical risk factors for thromboembolisms using different administration routes of early estrogen replacement therapy.

METHODS

In a 12-week prospective, randomized crossover trial, estradiol was administered orally (2 mg daily) or transdermally (0.05 mg daily). Forty-five healthy early postmenopausal women were included into the study within 12 weeks after hysterectomy and oophorectomy. Forty-one women (age 49 +/- 6 years) completed the study, and their data were analyzed. The hemocoagulation parameters were determined prior to beginning of the study and at the end of each treatment period, separated by a 1-week washout period.

RESULTS

After oral therapy, the average tissue factor pathway inhibitor levels decreased statistically significantly (p < 0.0001) from 87.5 +/- 39.1 to 68 +/- 37.49 ng/ml. The plaminogen activator inhibitor-1 levels also decreased statistically significantly (p = 0.001) after the oral estrogen therapy from 11.39 +/- 12.02 to 5.0 +/- 5.27 IU/l. These changes were also significant when compared with the nonsignificant changes after the transdermal therapy. No significant changes occurred in the levels of D-dimers. After both treatment methods, the antithrombin III and fibrinogen levels decreased, but within their physiological ranges.

CONCLUSIONS

Oral administration of estrogen statistically significantly reduced the tissue factor pathway inhibitor and plasminogen activator inhibitor-1 levels when compared with the transdermal route. These changes cannot be unambiguously considered risky, and the zero change of D-dimers suggests that there was no activation of the coagulation cascade. We consider the neutral effect of the transdermal therapy more beneficial.

Evidence-based treatment recommendations for uremic bleeding

Uremic bleeding syndrome is a recognized consequence of renal failure and can result in clinically significant sequelae. Although the pathophysiology of the condition has yet to be fully elucidated, it is believed to be multifactorial. This article is a review of both the normal hemostatic and homeostatic mechanisms that operate within the body to prevent unnecessary bleeding, as well as an in-depth discussion of the dysfunctional components that contribute to the complications associated with uremic bleeding syndrome. As a result of the multifactorial nature of this syndrome, prevention and treatment options can include one or a combination of the following: dialysis, erythropoietin, cryoprecipitate, desmopressin, and conjugated estrogens. Here, these treatment options are compared with regard to their mechanism of action, and onset and duration of efficacy. An extensive review of the clinical trials that have evaluated each treatment is also presented. Lastly, we have created an evidence-based treatment algorithm to help guide clinicians through most clinical scenarios, and answered common questions related to the management of uremic bleeding.

Menopause, estrogens, and endothelial dysfunction: current concepts

Menopause is defined as the permanent cessation of menses. Cardiovascular disease is the leading cause of death among postmenopausal women in developed countries. The disparity between the incidence of cardiovascular disease among women in pre- and postmenopause has been ascribed to the actions of endogenous estrogen on the cardiovascular system and, particularly, on the vascular endothelium. The endothelium plays an important role in cardiovascular homeostasis, either through the vascular tonus and its regulation, or through coagulation and the inflammatory response. Endothelial dysfunction is implicated in the genesis of atherosclerosis and other chronic disorders, such as diabetes mellitus and hypertension. The pharmacological use of estrogen exerts influence on the circulating levels of markers of vascular tonus, and inflammation, as well as prothrombotic, and fibrinolytic markers, but the impact of these changes on the atherosclerotic disease is still uncertain.

Meta-analysis: effect of hormone-replacement therapy on components of the metabolic syndrome in postmenopausal women

AIM

To quantify the effects of hormone-replacement therapy (HRT) on components of the metabolic syndrome in postmenopausal women.

METHODS

Comprehensive searches of electronic databases were performed from April 1966 to October 2004. We included randomized controlled trials that were of at least 8 weeks duration and evaluated the effect of HRT on metabolic, inflammatory or thrombotic components. Insulin resistance was calculated by homeostasis model assessment (HOMA-IR). Subgroup analysis evaluated the effects for transdermal and oral treatment and for diabetic and non-diabetic women.

RESULTS

Pooled results of 107 trials showed that HRT reduced abdominal fat [-6.8% (CI, -11.8 to -1.9%)], HOMA-IR [-12.9% (CI, -17.1 to -8.6%)] and new-onset diabetes [relative risk 0.7 (CI, 0.6-0.9)] in women without diabetes. In women with diabetes, HRT reduced fasting glucose [-11.5% (CI, -18.0 to -5.1%)] and HOMA-IR [-35.8% (CI, -51.7 to -19.8%)]. HRT also reduced low-density lipoprotein/high-density lipoprotein cholesterol ratio [-15.7% (CI, -18.0 to -13.5%)], lipoprotein(a) [Lp(a)] [-25.0% [CI, -32.9 to -17.1%)], mean blood pressure [-1.7% (CI, -2.9 to -0.5%)], E-selectin [-17.3% (CI, -22.4 to -12.1%)], fibrinogen [-5.5% (CI, -7.8 to -3.2%)] and plasminogen activator inhibitor-1 [-25.1% (CI, -33.6 to -15.5%)]. Oral agents produced larger beneficial effects than transdermal agents, but increased C-reactive protein (CRP) [37.6% (CI, 17.4-61.3%)] and decreased protein S [-8.6% CI, -13.1 to -4.1%)], while transdermal agents had no effect.

CONCLUSIONS

HRT reduces abdominal obesity, insulin resistance, new-onset diabetes, lipids, blood pressure, adhesion molecules and procoagulant factors in women without diabetes and reduced insulin resistance and fasting glucose in women with diabetes. Oral agents adversely affected CRP and protein S, while transdermal agents had no effects.

The differential association of conjugated equine estrogen and esterified estrogen with activated protein C resistance in postmenopausal women

OBJECTIVES

Clinical trials have demonstrated that oral conjugated equine estrogen (CEE) therapy with or without medroxyprogesterone (MPA) increases venous thrombotic risk but this safety issue has not been investigated for other oral estrogens. Based on observational study findings that esterified estrogen (EE) was not associated with venous thrombotic risk whereas CEE was, we hypothesized that CEE users would be more resistant to activated protein C (APC), a prothrombotic phenotype, than EE users.

METHODS

We conducted an observational, cross-sectional study of postmenopausal women 30-89 years old who were controls in a case-control study of venous thrombosis. Use of CEE, EE, and MPA at the time of phlebotomy was determined using computerized pharmacy records. APC resistance was measured in plasma by the endogenous thrombin potential normalized APC sensitivity ratio. Adjusted mean APC resistance values were compared across estrogen type and CEE:EE ratios are presented.

RESULTS

There were 119 CEE and 92 EE users at the time of phlebotomy. Compared with EE users, CEE users had APC resistance measures that were 52% higher (1.52; 95% confidence intervals: 1.07-2.17) in adjusted analyses. Restricting to modal dose users (0.625 mg) and stratifying by MPA use did not materially change associations.

CONCLUSIONS

CEE use was associated with higher levels of APC resistance when compared with EE use in postmenopausal women. These findings might provide an explanation for the higher risk of venous thromboembolism previously observed with CEE compared with EE use and, if replicated, may have safety implications for women when choosing an estrogen for symptom relief.

Effects of Transdermal Estrogen Replacement Therapy on Cardiovascular Risk Factors

The prevalence of hypertension and cardiovascular disease increases dramatically after menopause in women, implicating estrogen as having a protective role in the cardiovascular system. However, recent large clinical trials have failed to show cardiovascular benefit, and have even demonstrated possible harmful effects, of opposed and unopposed estrogen in postmenopausal women. While these findings have led to a revision of guidelines such that they discourage the use of estrogen for primary or secondary prevention of heart disease in postmenopausal women, many investigators have attributed the negative results in clinical trials to several flaws in study design, including the older age of study participants and the initiation of estrogen late after menopause.Because almost all clinical trials use oral estrogen as the primary form of hormone supplementation, another question that has arisen is the importance of the route of estrogen administration with regards to the cardiovascular outcomes. During oral estrogen administration, the concentration of estradiol in the liver sinusoids is four to five times higher than that in the systemic circulation. This supraphysiologic concentration of estrogen in the liver can modulate the expression of many hepatic-derived proteins, which are not observed in premenopausal women. In contrast, transdermal estrogen delivers the hormone directly into the systemic circulation and, thus, avoids the first-pass hepatic effect.Although oral estrogen exerts a more favorable influence than transdermal estrogen on traditional cardiovascular risk factors such as high- and low-density lipoprotein-cholesterol levels, recent studies have indicated that oral estrogen adversely influences many emerging risk factors in ways that are not seen with transdermal estrogen. Oral estrogen significantly increases levels of acute-phase proteins such as C-reactive protein and serum amyloid A; procoagulant factors such as prothrombin fragments 1+2; and several key enzymes involved in plaque disruption, while transdermal estrogen does not have these adverse effects.Whether the advantages of transdermal estrogen with regards to these risk factors will translate into improved clinical outcomes remains to be determined. Two ongoing clinical trials, KEEPS (Kronos Early Estrogen Prevention Study) and ELITE (Early versus Late Intervention Trial with Estradiol) are likely to provide invaluable information regarding the role of oral versus transdermal estrogen in younger postmenopausal women.

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.

Does body mass index, smoking, lipoprotein levels, surgically induced menopause, hormone replacement therapy, years since menopause, or age affect hemostasis in postmenopausal women?

BACKGROUND

Controversy still exists as to the relative importance of menopausal status and lifestyle factors for the risk of coronary heart disease in women.

OBJECTIVE

The purpose of this study was to assess the influence of body mass index (BMI), smoking,lipoprotein levels, surgically induced menopause, hormone replacement therapy (HRT), years since menopause, and age on hemostasis in apparently healthy postmenopausal women.

METHODS

Lipoproteins (total cholesterol [TC], low-density lipoprotein cholesterol, high-density lipoprotein cholesterol [HDL-C], triglycerides [TG]), and hemostatic factors (fibrinogen, von Willebrand factor antigen [vWFag], coagulation factors VIIag [FVIlag] and VIIa [FVIIa], plasminogen activator inhibitor 1 [PAI-1]) were each measured once. A forward, stepwise, multiple regression analysis was used to assess variations in hemostatic parameters.

RESULTS

A group of 292 healthy Stockholm women recruited from the census register participated in the Stockholm Female Coronary Risk Study as controls. Of these women, 260 participated in the present study. BMI, smoking, lipoprotein levels, surgically induced menopause, and years since menopause (1-5 y) were found to be associated with a 31% increase in fibrinogen levels. A 7% increase in FVIIa levels was attributed to TC, BMI, and HRT. Years since menopause (1-15 y), TG, TC, BMI, and HRT were associated with an increase of up to 26% in FVIIag levels. A 9% increase in vWFag correlated with HDL-C and years since menopause (1-10, 11-14, and > or =15 y). BMI and TG explained a 21% and 3% increase, respectively, in PAI-1 levels. Neither the use of HRT nor years since menopause had any influence on hemostasis.

CONCLUSION

BMI, high levels of TC and TG, and low HDL-C levels appear to be more important than hormonal status in their impact on hemostatic variables in healthy postmenopausal women.

Short-term effects of estrogen, tamoxifen and raloxifene on hemostasis: a randomized-controlled study and review of the literature

INTRODUCTION

Estrogen therapy (ET), tamoxifen and raloxifene are associated with a two- to three-fold increased risk of venous thrombosis (VT); however, the mechanisms by which each drug increases venous thrombosis propensity are not fully understood. The objectives of this investigation were to compare the effects of these three treatments on hemostasis in a head to head randomized placebo-controlled trial.

PATIENTS/METHODS

Ninety-four postmenopausal women were assigned to receive oral estrogen (conjugated equine estrogen [CEE] 0.625 mg, n=23), tamoxifen 20 mg (n=24), raloxifene 60 mg (n=24) or placebo (n=23) daily for 6 months. Blood samples were analyzed for procoagulant factors (prothrombin, factors VII [fVII], VIII [fVIII], IX [fIX] and XI [fXI], D-dimer and von Willebrand factor [vWf]), anticoagulant factors (antithrombin [AT], total and free protein S, protein C and activated protein C [APC] resistance) and fibrinolytic factors (thrombin activatable fibrinolysis inhibitor [TAFI] and plasminogen activator inhibitor-1 [PAI-1]), at baseline and at 6 months of treatment.

RESULTS

Estrogen increased factor VII and D-dimer, and decreased antithrombin, total and free protein S and PAI-1. Changes with tamoxifen were distinct from estrogen with increases in factors VIII, IX, vWf and free protein S, and decreases in AT, total protein S, protein C and plasminogen activator inhibitor-1. Raloxifene produced similar effects as tamoxifen, but did not increase factor IX or decrease protein C.

CONCLUSIONS

Estrogen, tamoxifen and raloxifene affected hemostasis favoring procoagulation and impairing anticoagulation. The biochemical effects of the selective estrogen receptor modulators (SERMs) were distinct from those of estrogen and differed only subtly from each other.

Hormone replacement therapy and cardiovascular disease: increased risks of venous thromboembolism and stroke, and no protection from coronary heart disease

Hormone replacement therapy (HRT) was increasingly promoted over the last 40 years to improve quality of life, and to reduce the risks of osteoporotic fractures and coronary heart disease (CHD). In recent years, observational studies, randomized trials and systematic reviews of such trials have shown that HRT does not reduce, but actually increases cardiovascular risk. HRT increases the relative risks of venous thromboembolism (twofold), and of fatal or disabling stroke (by 50%); whilst increasing the early risk of myocardial infarction and having no protective effect against CHD on longer term use. Possible mechanisms for these increased cardiovascular risks include down-regulation of several inhibitory pathways of blood coagulation, resulting in increased coagulation activation, which promotes venous and arterial thrombosis. The implications for prescription are discussed, as are lessons for future evaluation of health care interventions.

Positive impact of hormone replacement therapy on the fibrinolytic system: a long-term randomized controlled study in healthy postmenopausal women

BACKGROUND

The mechanisms by which postmenopausal hormone replacement therapy (HRT) may influence risk of cardiovascular disease are still unclear. Impaired fibrinolytic function is associated with an enhanced risk of cardiovascular disease and therefore the effect of HRT on fibrinolysis may be of importance.

OBJECTIVES

To investigate the prolonged effect of HRT on the fibrinolytic system and to determine whether two common polymorphisms in the plasminogen activator inhibitor-1 (PAI-1) and tissue-type plasminogen activator (t-PA) genes modulate this effect.

METHODS

Healthy postmenopausal women (n = 248) were randomized to HRT (n = 122) or no substitution (n = 126) 5 years prior to investigation.

RESULTS

Significantly higher values of t-PA activity and lower values of PAI-1 activity and PAI-1 antigen were found in the HRT group compared with the control group. This effect was independent of smoking and without influence from the two common polymorphisms PAI-1 -675(4G/5G) and t-PA intron8ins311. Furthermore, no difference between opposed estrogen (with norethisterone acetate as the gestagen component) and unopposed estrogen therapy was found. Both an intention-to-treat and a per-protocol analysis were performed and similar results were obtained.

CONCLUSIONS

Long-term treatment with HRT in healthy postmenopausal women was found to be associated with a beneficial fibrinolytic profile. This effect was found independent of smoking status, opposed and unopposed estrogen therapy had equal effect, and no influence of the two common polymorphisms PAI-1-675(4G/5G) and t-PA intron8ins311 was found. This effect of HRT on fibrinolytic capacity may be one of the beneficial effects of HRT in relation to cardiovascular diseases.

Differential effects of oral and transdermal estrogen/progesterone regimens on sensitivity to activated protein C among postmenopausal women: a randomized trial

OBJECTIVE

Activated protein C (APC) resistance not related to the factor V Leiden mutation is a risk factor for venous thrombosis. Oral estrogen replacement therapy (ERT) has been reported to induce APC resistance. Little is known about the effect of transdermal estrogen.

METHODS AND RESULTS

We enrolled 196 postmenopausal women who were randomly allocated to receive either 1 mg 17beta-estradiol orally (n=63) or 50 microg 17beta-estradiol transdermally per day (n=68), both associated with 100 mg progesterone daily or placebo (n=65) for 6 months. An activated partial thromboplastin time (APTT)-based test and the effect of APC on thrombin potential (ETP) were used. Oral ERT induced an ETP-based APC resistance compared with both placebo (P=0.006) and transdermal ERT (P<0.001), but there was no significant effect of transdermal ERT compared with placebo (P=0.191). There was no significant effect of ERT on the APTT-based APC sensitivity ratio. Prothrombin fragment 1+2 plasma levels were significantly higher after 6 months of treatment in women allocated to oral ERT compared with those on placebo and transdermal ERT and were positively and significantly correlated with changes in ETP-based APC sensitivity ratio.

CONCLUSIONS

Our data show that oral, unlike transdermal, estrogen induces APC resistance and activates blood coagulation. These results emphasize the importance of the route of estrogen administration.

Hormone replacement therapy and hypercoagulability. Results from the Prospective Collaborative Danish Climacteric Study

OBJECTIVE

To assess the influence of a variety of HRT regimens on the haemostatic balance using markers of fibrin turnover and inhibitors of coagulation.

DESIGN

An open randomised study allocating women to either a control group or five different HRT treatment groups.

SETTING

Gentofte Hospital, Hellerup, and Rigshospitalet, Copenhagen, Denmark.

POPULATION

One hundred and forty-nine postmenopausal women without previous venous thromboembolic disease.

METHODS

Prothrombin fragment 1+2 (F(1+2)), fibrin degradation products, antithrombin, protein C, total protein S and activated protein C-normalised ratio were measured at baseline and after 6 and 12 months of HRT in six groups of healthy postmenopausal women: (A). no HRT (reference group), (B). continuous oestradiol valerate (E(2)V) plus cyproterone acetate, (C). cyclic E(2)V plus cyproterone acetate, (D). continuous combined oestrogen (E(2)) plus norethindrone acetate, (E). E(2) combined with local delivery of levonorgestrel and (F). E(2)V plus medroxyprogesterone. HRT-induced changes in the concentration of inhibitors of coagulation and markers of fibrin turnover during 12 months of treatment.

RESULTS

Significant decreases of antithrombin and protein S were found in all treatment groups, of protein C in Groups C, D, E and F and of activated protein C-normalised ratio in Groups E and F. Fibrin degradation products increased after three months of treatment, whereas F(1+2) was persistently increased after three months in Group F. The cumulative response of antithrombin was significantly lower in Groups D, E and F than in the reference group. The cumulative response of protein S and activated protein C-normalised ratio was lower, whereas that of F(1+2) was significantly higher in Group F than in the reference group.

CONCLUSION

HRT reduces the inhibitory potential of coagulation significantly. The effect is related to the type of E(2)/progestin combination administered, but seems to be oestrogen-derived as the most pronounced effect is found with only quarterly progestin intake. Such procoagulant activity of HRT may well translate into clinical manifestations in thrombosis-prone individuals.

Effect of oral and transdermal estrogen replacement therapy on hemostatic variables associated with venous thrombosis: a randomized, placebo-controlled study in postmenopausal women

OBJECTIVE

The purpose of this study was to investigate whether the effect of transdermal estrogen therapy in postmenopausal women differs from that of oral therapy with regard to resistance to activated protein C (APC), an important risk factor for venous thrombosis, and levels of related proteins, such as protein S, protein C, and prothrombin.

METHODS AND RESULTS

In a randomized, double-blind, placebo-controlled study, 152 healthy hysterectomized postmenopausal women received daily either placebo (n=49), transdermal 17beta-estradiol (E2) 50 microg (tE2 group, n=33), oral E2 1 mg (oE2 group, n=37), or oral E2 1 mg combined with gestodene 25 microg (oE2+G group, n=33) for 13 28-day treatment cycles, followed by 4 cycles of placebo for each group. Plasma samples were collected at baseline and in cycles 4, 13, and 17. In cycle 13, significant increases versus baseline and placebo were found in normalized APC sensitivity ratios (nAPCsr) in all treated groups (tE2, +26.9%; oE2, +102.7%; oE2+G, +69.9%). Increases in nAPCsr were significantly higher in the oral treatment groups than in the tE2 group. In addition, compared with baseline and placebo, after 13 cycles, decreases were observed in total protein S (tE2, -4.1%; oE2, -7.9%; oE2+G, -5.8%), free protein S (tE2, -7.1%; oE2, -8.4%; oE2+G, -5.2%), and protein C in the oE2+G group (-6.4%), but these changes did not explain the increase in nAPCsr. Changes in prothrombin were small and also did not affect the nAPCsr.

CONCLUSIONS

Increases were observed in resistance to APC, which were more pronounced in the oral treatment groups than in the transdermal group. The increase in resistance to APC was not explained by changes in protein S, protein C, or prothrombin and may contribute to the increased incidence of venous thrombosis in users of hormone replacement therapy.

Hormone therapy and venous thromboembolism

Convincing data from randomized trials and observational studies have demonstrated a two- to threefold increased risk of venous thromboembolism (VTE) with the use of hormone replacement therapy (HRT) in post-menopausal women. This risk is highest in the first year of use, but an increased risk persists after the first year if HRT use is ongoing. The risk of VTE is increased for oral oestrogen alone, oral oestrogen combined with progestin and probably for transdermal HRT. There is an increase in both idiopathic and non-idiopathic VTE with HRT. Early evidence suggests an interaction of HRT with thrombophilic states such as the factor V Leiden mutation, resulting in a synergistic increase in the risk of VTE. There is also an increased risk of VTE with raloxifene and tamoxifen, but the effects of low-dose HRT and tibolone on VTE risk are less clear.

Hormone replacement therapy and risk of cardiovascular disease: implications of the results of the Women's Health Initiative

The higher rates of coronary heart disease (CHD), stroke, and venous thrombosis among women taking estrogen and progesterone (E+P) compared with placebo in the Women's Health Initiative clinical trial have important implications for women's health. Previous studies in both men and women have shown that estrogen therapy lowers low-density lipoprotein cholesterol and raises high-density lipoprotein cholesterol. The changes in these lipoproteins should be associated with at least a 30% decline in CHD risk. Estrogens increased very-low-density lipoprotein (VLDL) triglyceride levels and C-reactive protein. There is evidence that estrogens increase thrombin generation and fibrinolysis. The increase in VLDL triglycerides may enhance thrombotic risk as well as higher levels of atherogenic lipoproteins, such as dense low-density lipoprotein. Genetic variations in estrogen receptors and thrombosis or fibrinolysis may also be important in risks associated with E+P therapy. The increased risk of CHD and stroke with E+P therapy may be attributable to rise in VLDL triglycerides and thrombosis.

Influence of socioeconomic status and job control on plasma fibrinogen responses to acute mental stress

OBJECTIVE

An elevation in plasma fibrinogen may be one of the pathways through which low socioeconomic status increases cardiovascular disease risk. This study assessed the influence of socioeconomic status, job control, and social isolation on fibrinogen responses to acute stress.

METHODS

The study was conducted with 125 white men and 96 white women aged 47 to 58 years, drawn from the Whitehall II cohort. Socioeconomic status was indexed by grade of employment, with 82 high, 75 intermediate, and 64 low grade participants. Plasma fibrinogen and hematocrit were assessed at baseline, immediately after performance of color-word and mirror tracing tasks, and 45 minutes later.

RESULTS

Plasma fibrinogen increased from baseline to stress (from 2.85 +/- 0.57 to 2.92 +/- 0.58 g/liter), remaining elevated 45 minutes after stress (2.89 +/- 0.58 g/liter, p <.001). Fibrinogen concentration was greater in the low than in the high or intermediate employment grade groups, independently of sex, age, body mass index, smoking status, and hematocrit. Fibrinogen responses to acute stress did not differ across employment grades. Women had higher fibrinogen levels than men, but this pattern was abolished in women taking hormone replacement therapy. Men experiencing low job control showed greater fibrinogen responses to acute stress than did those with high job control (p =.003). Fibrinogen levels were greater in socially isolated individuals, but social isolation did not affect responses to acute stress.

CONCLUSIONS

Socioeconomic status and acute stress had independent effects on the plasma fibrinogen level. Low job control may influence cardiovascular disease risk in men partly through provoking greater fibrinogen stress responses.

Oral conjugated equine estrogen increases plasma von Willebrand factor in postmenopausal women

OBJECTIVES

We sought to test whether one month of daily oral conjugated equine estrogen (CEE) or transdermal estradiol alters hemostatic factors in postmenopausal subjects.

BACKGROUND

Estrogen replacement therapy and hormonal replacement therapy (HRT) effect an early increase in cardiovascular events in postmenopausal women. Circulating plasma von Willebrand factor (vWF) antigen is a marker of generalized endothelial dysfunction and atherothrombosis.

METHODS

Thirty-eight healthy postmenopausal women (average 59 +/- 7 years) were randomized to receive daily oral CEE, 0.625 mg (n = 21); transdermal estradiol, 0.1 mg/day (n = 7); or oral placebo (n = 10) for one month. Blood samples were collected at baseline and after two weeks and four weeks of therapy for measurement of circulating plasma hormones, lipid concentrations, and hemostatic factors.

RESULTS

Oral CEE decreased total cholesterol (p < 0.01) and low-density lipoprotein cholesterol (p < 0.01), although it increased both triglycerides (p < 0.05) and high-density lipoprotein cholesterol (p < 0.01). Transdermal estradiol had no significant effect on lipids. Plasminogen activator inhibitor-1 antigen declined in both oral CEE and transdermal estradiol users, but did not achieve statistical significance. Fibrin D-dimer antigen did not vary significantly in any group. However, oral CEE users had a significant increase in vWF from baseline to four weeks (p < 0.03) and a decrease in tissue-type plasminogen activator antigen from baseline to four weeks (p < 0.004), which was significantly different from the change observed in the transdermal estradiol group (p < 0.05).

CONCLUSIONS

These data suggest that the oral CEE-mediated increase in plasma vWF may have clinical relevance given the early atherothrombotic effects of HRT in postmenopausal women.

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.