Menopausal status associated with increased inhibition of blood coagulation

Impact of Sex on Outcomes With Femoral Artery Closure Devices Versus Manual Compression in Patients Undergoing Percutaneous Coronary Intervention

Background and Aims

Femoral artery access is widely used despite recent increase in radial access for percutaneous coronary interventions (PCI). Femoral artery closure devices are used to shorten vascular closure time and reduce bleeding. We sought to examine sex-based outcomes of femoral artery vascular closure devices (VCD) in patients undergoing PCI.

Methods

We identified patients who had undergone PCI (n = 11,415) in the Indiana University Health Multicenter Cardiac Cath registry using femoral artery access. Clinical outcomes were compared between VCD and manual compression and analyzed according to sex. Patients with cardiogenic shock and left ventricular support devices were excluded.

Results

The use of any vascular closure device as compared to femoral artery manual compression was associated with a reduction in 72-h bleeding events (adjusted odds ratio [OR]: 0.64; 95% confidence interval [CI]: 0.46-0.87). With manual compression, women had higher rates of 72-h bleeding as compared to men (4.5% vs. 1.6%, p < 0.001). Women demonstrated greater absolute risk reduction in 72-h bleeding events with use of VCD as compared to men (2.8% vs. 0.8%, p < 0.001). For women, VCD were associated with lower risk of access site bleeding (OR: 0.43; 95% CI: 0.24-0.8), hematoma (OR: 0.36; 95% CI: 0.2-0.63), and vascular complications (OR: 0.25, 95% CI: 0.09-0.72). Use of VCD was associated with lower risk of in-hospital death (adjusted OR: 0.4; 95% CI: 0.28-0.58; p < 0.001) in multivariable regression analysis.

Conclusion

Women derive more benefit from use of femoral artery VCD during PCI than men with greater reduction in bleeding rates, access site hematoma, and vascular complications.

Hemostatic Factors and Ischemic Heart Disease Risk Among Postmenopausal Women

The following is a review of (largely) epidemiologic evidence on whether changes in plasma hemostatic concentrations occur with menopause and with postmenopausal hormone therapy which may have an impact on risk of ischemic heart disease. To date, only plasma fibrinogen has been positively associated with long-term risk of disease among women; however, data are sparse. Taken together, the evidence supports an impact of endogenous sex hormone levels on thrombotic potential and points to a modest increase in a number of plasma hemostatic factor levels at menopause. Results of studies of estrogen therapy are somewhat conflicting. Observational findings suggest that, except for possibly the Factor VII level, estrogen therapy may prevent the menopause-related rise in plasma hemostatic factors. In contrast, controlled experiments have found increased markers of thrombin generation with use of common formulations of estrogen therapy. The hemostatic effects found with oral preparations do not appear to occur with transdermal forms of estrogen although data are limited. Overall, the evidence shows menopause to have an impact on plasma levels of hemostatic factors which appears to be modified by use of oral estrogen. Whether these alterations in plasma levels have an impact on risk of ischemic heart disease among postmenopausal women remains to be demonstrated.

Transdermal estrogen replacement therapy: beneficial effects on hemostatic risk factors for cardiovascular disease

OBJECTIVES

To assess the effect of estrogen replacement therapy on hemostatic risk factors for cardiovascular disease (CVD) in postmenopausal women during 2 years of treatment.

METHODS

In an open prospective study, patients (n = 42) were investigated before and during 2 years of treatment, and compared to an untreated postmenopausal control group (n = 18) followed during the same period, healthy premenopausal women (n = 20) being included as a reference group for premenopausal values. The patients underwent treatment with transdermal 17 beta-estradiol (E2) (50 micrograms/24 h), oral medroxyprogesterone acetate (5 mg/day) being added for 12 days every second month.

RESULTS

After 2 years of treatment there was a significant increase in t-PA antigen (P = 0.01) and a significant decrease in F VII antigen (P = 0.01). PAI-1 antigen concentrations decreased slightly. Fibrinogen concentrations were already significantly decreased at 3-month follow-up (P = 0.01), and were still low after 2 years. By contrast, at 2-year follow-up the postmenopausal control group manifested significant increases in F VII and PAI-1 antigen and slight increases in fibrinogen, which resulted in significant differences between patients and controls. Regression analysis showed the increase in the serum estradiol concentrations to be inversely correlated to the decreases in the plasma concentrations of F VII antigen (r = -0.34, P = 0.001) and fibrinogen (r = -0.35, P = 0.001). There were no changes in AT III or protein C in any group.

CONCLUSIONS

The increase in serum estradiol concentrations due to replacement therapy did not adversely affect the studied components of the fibrinolytic and protein C defense system against thrombosis, and resulted in beneficial decreases in F VII antigen and fibrinogen. These findings may help to explain the beneficial effects of estrogen replacement therapy in terms of protection from cardiovascular disease.

Estrogen induction and contact phase activation of human factor XII

This paper reviews data reported in the literature and results of our experiments on the transcriptional control of Factor XII by estrogens and on the activation of Factor XII in the plasma. Coagulation Factor XII (Hageman factor, FXII) is a serine protease secreted by the liver and activated by negative charged surfaces to play roles in fibrinolysis, coagulation, and inflammation. Multiple effects on hemostasis involving these processes via Hageman factor have been reported in relation to estrogen therapy. The nucleotide sequence of 3,174 base pair (bp) DNA at the 5' end of the Factor XII gene indicates that the Factor XII promoter is typical of TATA-less, liver-specific, and serine protease-type eukaryotic genes involved in clotting. In addition the Factor XII promoter contains at position -44/-31 a palindrome similar, but not identical, to an estrogen-responsive element (ERE) together with four hemisite EREs between positions -1314 and -608. These promoter regions may underlie the mechanism by which estrogens enhance Factor XII concentrations in plasma. In vivo, a 6-fold stimulation of FXII gene transcription by 17 beta-estradiol was observed in ovariectomized rats. In vitro a 230-bp promoter fragment of Factor XII (-181/+49) confers a strong 17 beta-estradiol responsiveness onto a chlorampenicol acetyltransferase reporter when transiently co-transfected with the human estrogen receptor. The domain structure of Factor XII allows identification of those parts of the protein with particular functions. cDNA constructs, in which sequences coding for selected domains were deleted, were used to produce recombinant deleted Factor XII proteins in a vacinia virus expression system. To identify the domain(s) responsible for contact phase activation, these recombinant proteins were tested for their capacity to bind to negatively charged substrates, to become activated by kallikrein, and to sustain blood clotting and amidolytic activity. In addition to the N-terminal domain, the growth factor and kringle domains and, to a lesser extent, the polyproline region also interact with negatively charged surfaces and presumably thus contribute to activation.

The regulation of plasminogen activators and plasminogen activator inhibitor type 1 in endothelial cells by sex hormones

OBJECTIVE

The purpose of this study was to assess the effect of 17 beta-estradiol, progesterone, and testosterone on secretion of plasminogen activators and plasminogen activator inhibitor type 1 by cultured endothelial cells.

STUDY DESIGN

Bovine aortic endothelial cells were cultured in medium that contained 17 beta-estradiol, progesterone, or testosterone at various concentrations (10(-13) to 10(-6) mol/L). Plasminogen activator activity in culture medium in the presence of cells was assayed after a 36-hour incubation using chromogenic substrate and iodine 125-labeled fibrin plate assays. Plasminogen activator inhibitor type 1 antigen was detected in conditioned media of bovine aortic endothelial cells by Western blotting analysis.

RESULTS

All three steroid hormones exhibited biphasic dose-response effects, characterized by stimulation of plasminogen activator secretion at lower concentrations and inhibition of plasminogen activator secretion at higher concentrations. A significant stimulatory effect on plasminogen activator secretion (74% over control) was observed at a 17 beta-estradiol concentration of 10(-12) mol/L (p < 0.03). At higher concentrations of 17 beta-estradiol, progesterone, and testosterone, inhibition of plasminogen activator secretion was observed (p < 0.05). Decreased levels of plasminogen activator inhibitor type 1 antigen were detected in supernatants treated with either 17 beta-estradiol or progesterone at a concentration of 10(-12) mol/L and were maximal at 10(-7) mol/L 17 beta-estradiol, progesterone, and testosterone.

CONCLUSION

The secretion of plasminogen activators and plasminogen activator inhibitor type 1 is regulated in a biphasic dose-dependent manner by sex hormones in bovine aortic endothelial cells.

The effect of two regimens of hormone replacement therapy on the haemostatic profile in postmenopausal women

The effect of two different regimens of hormone replacement therapy on coagulation and fibrinolysis was measured in 30 women taking Tibolone (Livial) and 30 taking oestradiol valerate, sequentially combined with cyproterone acetate (Climen). Blood samples were taken before the beginning of the medication, then six and twelve months afterwards. The Livial group showed a rise of fibrinolytic activity as measured by the alpha 2-antiplasmin-plasmin complexes. Tissue plasminogen activator antigen and plasminogen activator inhibitor-1 decreased simultaneously. No effect was seen in the coagulation variables. In the Climen group no significant alterations were noticed, either in the coagulation or in the fibrinolysis variables. In the direct comparison of both substances only factor VII appeared to be significantly higher in the Climen group after six months and one year of treatment.

Dyslipoproteinemia in women and the elderly

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

Effect of transdermal oestradiol on the haemostatic balance of menopausal women

OBJECTIVE

To determine the effect of transdermal oestrogen replacement therapy on the haemostatic balance of menopausal women.

DESIGN

Open, parallel group, prospective study.

SETTING

Three hospital-based menopause clinics.

SUBJECTS

Fifty-two postmenopausal women receiving transdermal hormone replacement therapy (Estrapak 50) for 6 months. Comparison group of 48 untreated postmenopausal women studied in parallel.

MAIN OUTCOME MEASURES

Changes in platelet number, plasma concentrations of coagulation factors and their natural inhibitors, fibrinolytic activity, and rheological parameters.

RESULTS

Estrapak 50 had no significant thrombophilic effect on any of the outcome measures.

CONCLUSION

The haemostatic balance and thus the risk of thrombosis would not appear to be upset by this dose of transdermal oestrogen.

The effect of oestrogen on the female cardiovascular system

OBJECTIVE

To review the present state of knowledge regarding the effect of oestrogen on the female cardiovascular system (e.g. atherosclerosis, myocardial infarction, hypertension and thrombosis).

DATA SOURCES

Over 100 articles (most published over the last 10 years) were reviewed. They included epidemiological, biochemical, physiological, animal and clinical studies which related to the effect oestrogens have on the cardiovascular system of postmenopausal women. These data contained a wide cross-section of results and outcomes and each study was summarised to provide the most relevant information. Where a particular study provided an opinion or result at variance with the majority opinion, that study has been discussed in greater detail.

STUDY SELECTION

All published papers which appeared to be relevant to an understanding of the clinical implications of oestrogen replacement therapy and its impact on the female cardiovascular system were included in this analysis. Some papers which appeared to repeat data and results previously published were not included.

DATA SYNTHESIS

The overwhelming eight of evidence from this literature review supports the concept that oestrogen reduces the risk of atherosclerosis and myocardial infarction. It also confirms that postmenopausal "natural" oestrogen is a vasodilating agent which will lead to a fall in blood pressure and an improvement in blood flow and the pulsatility index. Although oral oestrogen did appear to increase thrombogenic activity, there was no clinical evidence that "natural" oestrogen taken after the menopause increased the risk of venous thrombosis.

CONCLUSIONS

The consensus of the published data is that oestrogen conveys a highly protective effect on the cardiovascular system of postmenopausal women. There will be a reduction of up to 50% in myocardial infarction and stroke, a reduction in the incidence of hypertension and an improvement in blood flow. Some of the data suggest that even for women who have suffered from an infarct, their long-term survival is enhanced by oestrogen therapy. The medical myth that oestrogen has a deleterious effect on the cardiovascular system of women is finally laid to rest.

Hemostatic factors according to menopausal status and use of hormone replacement therapy

The rise in cardiovascular disease (CVD) risk after menopause may be reduced by hormone replacement therapy (HRT) although the mechanism is unclear. Because little is known about the potential role of hemostatic factors, fibrinogen level and other coagulation parameters were measured in a study on the change in CVD risk factors through the climacteric (the Healthy Women Study). Of 239 subjects measured to date, 32 taking aspirin or other medications thought to alter coagulation were excluded from analyses. Results (adjusted for age and obesity) showed that women taking HRT had lower plasma concentrations of fibrinogen and higher levels of plasminogen and factor VIIc than did postmenopausal subjects not taking HRT. Pre- as compared with postmenopausal women had lower plasma levels of fibrinogen, factor VIIc, and antithrombin III. Adjusting for cigarette smoking did not change the findings. Thus, among women aged 49 to 55, selected hemostatic measures varied (within normal ranges) by menopausal status and were altered by HRT. These findings generally support a hypothesis of hemostatic change contributing to the increase of CVD after menopause. The fact that subjects taking HRT showed no increase in fibrinogen relative to premenopausal women is consistent with an observed decreased risk of CVD among women taking HRT, while the implication of an elevation in factor VIIc among these women is uncertain.

Lipids, clotting factors, and diabetes: endogenous risk factors for cardiovascular disease

Theories of intimal injury leading to plaque formation include platelet adhesion and production of growth factors, hypercholesterolemia, smooth muscle cell proliferation, macrophage activity, defective utilization of low-density lipoproteins via deficient receptors, and deficiency in cellular lysosomal enzymes. High levels of low-density lipoproteins and intermediate-density lipoproteins, as well as their apoproteins, are strong risk factors for cardiovascular disease. The lowering of the cholesterol level has been shown to produce significant regression of atherosclerotic lesions. Data also suggest an interaction between lipids and platelets, although the role of coagulation disorders as an independent risk factor for atherosclerosis is difficult to assess. Although much of the data are controversial, there is evidence that platelet survival time is a strong predictor of severe vessel damage. In addition, some studies have reported decreased activity of antithrombin III with coronary artery disease, and there appears to be a direct correlation between fibrinogen and cholesterol levels. Finally, diabetes mellitus (both types I and II) is a significant independent risk factor for atherosclerosis. The risk is not related to the severity or duration of diabetes, and it appears to be greater in women than in men.