Relation of hemostatic risk factors to other risk factors for coronary heart disease and to sex hormones in men

Higher testosterone and testosterone/estradiol ratio in men are associated with decreased Pheno-/GrimAge and DNA-methylation based PAI1

Sex hormones are hypothesized to drive sex-specific health disparities. Here, we study the association between sex steroid hormones and DNA methylation-based (DNAm) biomarkers of age and mortality risk including Pheno Age Acceleration (AA), Grim AA, and DNAm-based estimators of Plasminogen Activator Inhibitor 1 (PAI1), and leptin concentrations. We pooled data from three population-based cohorts, the Framingham Heart Study Offspring Cohort, the Baltimore Longitudinal Study of Aging, and the InCHIANTI Study, including 1,062 postmenopausal women without hormone therapy and 1,612 men of European descent. Sex-stratified analyses using a linear mixed regression were performed, with a Benjamini-Hochberg (BH) adjustment for multiple testing. Sex Hormone Binding Globulin (SHBG) was associated with a decrease in DNAm PAI1 among men (per 1 standard deviation (SD): -478 pg/mL; 95%CI: -614 to -343; P:1e-11; BH-P: 1e-10), and women (-434 pg/mL; 95%CI: -589 to -279; P:1e-7; BH-P:2e-6). The testosterone/estradiol (TE) ratio was associated with a decrease in Pheno AA (-0.41 years; 95%CI: -0.70 to -0.12; P:0.01; BH-P: 0.04), and DNAm PAI1 (-351 pg/mL; 95%CI: -486 to -217; P:4e-7; BH-P:3e-6) among men. In men, testosterone was associated with a decrease in DNAm PAI1 (-481 pg/mL; 95%CI: -613 to -349; P:2e-12; BH-P:6e-11). SHBG was associated with lower DNAm PAI1 among men and women. Higher testosterone and testosterone/estradiol ratio were associated with lower DNAm PAI and a younger epigenetic age in men. A decrease in DNAm PAI1 is associated with lower mortality and morbidity risk indicating a potential protective effect of testosterone on lifespan and conceivably cardiovascular health via DNAm PAI1.

Higher testosterone and testosterone/estradiol ratio in men are associated with better epigenetic estimators of mortality risk

Introduction

Sex hormones are hypothesized to drive sex-specific health disparities. Here, we study the association between sex steroid hormones and DNA methylation-based (DNAm) biomarkers of age and mortality risk including Pheno Age Acceleration (AA), Grim AA, and DNAm-based estimators of Plasminogen Activator Inhibitor 1 (PAI1), and leptin concentrations.

Methods

We pooled data from three population-based cohorts, the Framingham Heart Study Offspring Cohort (FHS), the Baltimore Longitudinal Study of Aging (BLSA), and the InCHIANTI Study, including 1,062 postmenopausal women without hormone therapy and 1,612 men of European descent. Sex hormone concentrations were standardized with mean 0 and standard deviation of 1, for each study and sex separately. Sex-stratified analyses using a linear mixed regression were performed, with a Benjamini-Hochberg (BH) adjustment for multiple testing. Sensitivity analysis was performed excluding the previously used training-set for the development of Pheno and Grim age.

Results

Sex Hormone Binding Globulin (SHBG) is associated with a decrease in DNAm PAI1 among men (per 1 standard deviation (SD): -478 pg/mL; 95%CI: -614 to -343; P:1e-11; BH-P: 1e-10), and women (-434 pg/mL; 95%CI: -589 to -279; P:1e-7; BH-P:2e-6). The testosterone/estradiol (TE) ratio was associated with a decrease in Pheno AA (-0.41 years; 95%CI: -0.70 to -0.12; P:0.01; BH-P: 0.04), and DNAm PAI1 (-351 pg/mL; 95%CI: -486 to -217; P:4e-7; BH-P:3e-6) among men. In men, 1 SD increase in total testosterone was associated with a decrease in DNAm PAI1 (-481 pg/mL; 95%CI: -613 to -349; P:2e-12; BH-P:6e-11).

Conclusion

SHBG was associated with lower DNAm PAI1 among men and women. Higher testosterone and testosterone/estradiol ratio were associated with lower DNAm PAI and a younger epigenetic age in men. A decrease in DNAm PAI1 is associated with lower mortality and morbidity risk indicating a potential protective effect of testosterone on lifespan and conceivably cardiovascular health via DNAm PAI1.

Prospective Study of Endogenous Hormones and Incidence of Venous Thromboembolism: The Atherosclerosis Risk in Communities Study

Exogenous hormone treatments in women (oral contraceptives and hormone replacement therapy [HRT]) are established risk factors for venous thromboembolism (VTE), but less is known about associations between plasma levels of endogenous hormones and VTE risk. We examined the association of baseline dehydroepiandrosterone sulphate (DHEAS), testosterone and sex hormone-binding globulin (SHBG) with risk of future VTE in men and post-menopausal women in the Atherosclerosis Risk in Communities Study. Testosterone, DHEAS and SHBG were measured in plasma samples collected in 1996 to 1998. Cox proportional hazards models were used to estimate hazard ratios for incident VTE adjusting for age, race/ethnicity, body mass index, height, smoking, estimated glomerular filtration rate and C-reactive protein. All analyses were stratified by sex and by current HRT use in women. Among 3,051 non-HRT-using women, 1,414 HRT-using women and 3,925 men at risk at baseline, 184, 62 and 206 experienced incident VTE after a median follow-up of 17.6 years. Plasma hormones were not associated with incidence of VTE among men and non-HRT-using women, although lower plasma DHEAS, when modelled using quartiles or restricted cubic splines, was associated with higher risk of VTE among HRT-using women. This study does not support the existence of an important association between plasma concentrations of endogenous testosterone, DHEAS or SHBG with risk of VTE in middle-aged to older men or post-menopausal women not using HRT.

The Effect of Testosterone on Cardiovascular Disease

Cardiovascular disease is the leading cause of death in the United States. Testosterone is the principal male sex hormone and plays an important role in men’s health and well-being. Historically, testosterone was believed to adversely affect cardiovascular function. However, contemporary literature has refuted this traditional thinking; testosterone has been suggested to have a protective effect on cardiovascular function through its effects on the vascular system. Data from modern research indicate that hypogonadism is closely related to the development of various cardiovascular risk factors, including hyperlipidemia and insulin resistance. Several studies have demonstrated beneficial effects of testosterone supplementation therapy on reversing symptoms of hypogonadism and improving cardiovascular disease risk profiles. In this review, we perform a critical analysis on the association between testosterone and cardiovascular disease.

Androgen activity and markers of inflammation among men in NHANES III

OBJECTIVES

Inflammation contributes to chronic diseases. Lower serum testosterone among men is associated with less inflammation, yet immune defense is thought to trade-off against reproduction with androgens adversely affecting immune function. Anti-androgens are effective at castrate levels of serum testosterone, suggesting serum testosterone may not capture all androgen activity. The association of two androgen biomarkers with key markers of inflammation was examined.

METHODS

The adjusted association of serum testosterone and androstanediol glucuronide with C-reactive protein, white blood cell, granulocyte and lymphocyte count, fibrinogen, and hemoglobin, as a control outcome because testosterone administration raises hemoglobin, were examined in a nationally representative sample of 1,490 US men from the National Health and Nutrition Examination Survey III phase 1 (1988-1991) using multivariable linear regression.

RESULTS

Serum testosterone and androstanediol glucuronide were weakly correlated (0.13). Serum testosterone was associated with lower white blood cell count [-0.26 × 10(-9) per standard deviation, 95% confidence interval (CI) -0.37 to -0.14] and granulocyte count (-0.21 × 10(-9) , 95% CI -0.29 to -0.13) but not with hemoglobin (0.02 g/l, 95% CI -0.89 to 0.92), adjusted for age, education, race/ethnicity, smoking, and alcohol. Similarly adjusted, androstanediol glucuronide was not associated with white blood cell count (0.10 × 10(-9) , 95% CI -0.05 to -0.25), granulocyte count (0.12 × 10(-9) , 95% CI -0.02 to 0.25), or fibrinogen (0.05 g/l, 95% CI -0.004 to 0.11), but was with hemoglobin (0.70 g/l, 95% CI 0.07 to 1.32).

CONCLUSIONS

Different androgen biomarkers had different associations with inflammatory markers, highlighting the need to consider several androgen biomarkers. The possibility remains that androgens may generate inflammatory processes with implications for chronic diseases.

A J-shaped association between plasma testosterone and risk of ischemic arterial event in elderly men: the French 3C cohort study

OBJECTIVES

Low plasma testosterone is associated with increased mortality in men. However, the relation between testosterone and cardiovascular disease is uncertain. We assessed the association of plasma sex hormones with the incidence of ischemic arterial disease (IAD) in elderly men.

METHODS

We used data from the French Three-City prospective cohort study (3650 men aged >65 years). A case-cohort design was set up including a random sample of 495 men and 146 incident cases of first IAD event (112 coronary heart disease (CHD) and 34 strokes) after a 4-year follow-up. Plasma total and bioavailable testosterone, total estradiol and sex hormone-binding globulin (SHBG) were measured at baseline. Multivariate hazard ratios (HRs) and 95% confidence intervals for IAD were assessed using Cox model.

RESULTS

After adjustment for cardiovascular risk factors, a J-shaped association between plasma total testosterone and IAD risk was found (p<0.01). The HRs associated with the lowest and the highest total testosterone quintiles relative to the second quintile were 2.23 (95% CI: 1.02; 4.88) and 3.61 (95% CI: 1.55; 8.45) respectively. Additional analysis for CHD showed similar results (HR: 3.11, 95% CI: 1.27; 7.63 and HR: 4.75, 95% CI: 1.75; 12.92, respectively). Similar J-shaped association was observed between bioavailable testosterone and IAD risk (p=0.01). No significant association of estradiol and SHBG with IAD was found.

CONCLUSION

High and low plasma testosterone levels are associated with an increased risk of IAD in elderly men. Optimal range of plasma testosterone may confer cardiovascular protection and these results may have clinical implications in the management of testosterone deficiency.

Association between Relative Hypogonadism and Metabolic Syndrome in Newly Diagnosed Adult Male Patients with Impaired Glucose Tolerance or Type 2 Diabetes Mellitus

Sex steroid hormones are known to be important regulators of the lipid and glucose metabolism. Lower levels of testosterone (T) or sex hormone-binding globulin (SHBG) have been reported in men with type 2 diabetes. On the other hand, the relationship between relative hypogonadism and metabolic syndrome has not yet to be thoroughly studied. Ninety-eight Japanese adult (age 20-64) male patients with impaired glucose tolerance (IGT) or type 2 diabetes mellitus were divided into either an metabolic syndrome group (n = 42) or a non- metabolic syndrome (n = 56) group according to the definition of metabolic syndrome from WHO, or into three tertiles according to their sex hormone index level. The metabolic syndrome group had a significantly lower T/estradiol (E(2)) and SHBG level (p < 0.01). The age and subcutaneous fat surface area (SFA) were significantly different within the tertiles in SHBG and T/E(2). Logistic regression analyses were performed to investigate the association between the sex steroid hormone index level and the incidence of metabolic syndrome. Regarding the highest tertiles as a criterion, lower SHBG, T/E(2) or free T/E(2) had a higher odds ratio of prevalence of metabolic syndrome even after adjusting for age and SFA. Relative hypogonadism was strongly associated with the prevalence of metabolic syndrome in Japanese adult men who were newly diagnosed to have IGT or type 2 diabetes.

Plasma testosterone is associated with Framingham risk score

INTRODUCTION

The Framingham risk score predicts a patient's 10-year risk of developing cardiovascular disease. Many risk factors included in its calculation influence or are influenced by circulating testosterone. To investigate the possible association between testosterone and cardiovascular risk, as defined by the Framingham score, a Veterans Affairs (VA) database was analyzed.

METHODS

A retrospective chart review was performed. Inclusion criteria were male sex and age ≥ 20 years. Exclusion criteria included pre-existing cardiovascular disease, stroke, and diabetes. Data were collected on veterans who had total plasma testosterone checked in the year 2008.

RESULTS

The study included 1,479 patients (mean age 61 years). Framingham score was negatively associated with both total testosterone (p < 0.0001) and free testosterone (p = 0.0003). There was a positive association between total testosterone and high-density lipoprotein and negative associations between total testosterone and body mass index (BMI), total cholesterol, triglycerides, and blood pressure medication use. Free testosterone was positively associated with total cholesterol, low-density lipoprotein, and current smoking status and negatively associated with age, BMI, and blood pressure medication use. The BMI was not associated with Framingham score.

CONCLUSIONS

Lower plasma testosterone may suggest the presence of cardiovascular risk factors and potentially increased risk for heart disease.

Low plasma testosterone and elevated carotid intima-media thickness: importance of low-grade inflammation in elderly men

CONTEXT AND OBJECTIVE

An inverse correlation between plasma testosterone levels and carotid intima-media thickness (IMT) has been reported in men. We investigated whether this association could be mediated or modified by traditional cardiovascular risk factors as well as inflammatory status.

METHODS

In the Three-City population-based cohort study, 354 men aged 65 and over had available baseline data on hormones levels and carotid ultrasonography. Plasma concentrations of testosterone (total and bioavailable), estradiol and sex hormone-binding globulin (SHBG), together with cardiovascular risk factors were measured. IMT in plaque-free site and atherosclerotic plaques in the extracranial carotid arteries were determined using a standardized protocol. Multiple linear regression models were used to analyze this association and interaction study.

RESULTS

Analyses with and without adjustment for cardiovascular risk factors showed that carotid IMT was inversely and significantly correlated with total and bioavailable testosterone levels but not with SHBG and estradiol levels. This association depended on C-reactive protein (CRP) levels (p for interaction <0.05). Among men with low-grade inflammation (CRP ≥2 mg/L), mean IMT was higher in subjects with bioavailable testosterone ≤ 3.2 ng/mL than in those with bioavailable testosterone > 3.2 ng/mL (0.76 mm and 0.70 mm respectively, p < 0.01). By contrast, among men with CRP ≤ 2 mg/L, mean IMT was similar in both groups (0.72 mm and 0.71 mm respectively, p = 0.77). Similar results were found for total testosterone although not significant. No association was found between plasma hormones levels and atherosclerotic plaques.

CONCLUSION

In elderly men, low plasma testosterone is associated with elevated carotid intima-media thickness only in those with low-grade inflammation. Traditional risk factors have no mediator role.

Relationship between testosterone deficiency and cardiovascular risk and mortality in adult men

Classic male hypogonadism is associated with known adverse effects including decreased libido, erectile dysfunction, osteoporosis, and changes in body composition. Recently, we have come to appreciate that reduction in serum testosterone (T) levels resulting from aging or chronic disease or androgen deprivation therapy (ADT) have consequences similar to those seen in classic male hypogonadism which include increased fat mass, decreased lean body mass, decreased muscle strength, and sexual dysfunction. These data suggest that low T levels may represent a newly recognized cardiometabolic risk factor. Therefore, we carried out a careful review of the literature, focusing on major turning points of research and studies which gave more important and controversial contribution to the cardiovascular role of T. Observational studies and clinical trials investigating the relationship between T levels and cardiovascular disease and mortality were identified byMedline search. The results were synthesized, tabulated, and interpreted. The aim of this review is to discuss the association between low T levels and adverse metabolic profile such as insulin resistance, metabolic syndrome, and diabetes. We will also investigate the potential mechanisms by which male hypogonadism, especially age related or induced by ADT, may increase cardio-metabolic risk. Finally we will detail the emerging relationship between low T and mortality in men addressing also the reverse hypothesis that low T has a protective role by turning off T-dependent functions.

Markers of inflammation and hemodynamic measurements in obesity: Copenhagen City Heart Study

BACKGROUND

Low-grade chronic inflammation has been proposed to play a major role in the pathogenesis of hypertension. Low-grade chronic inflammation is also closely associated with obesity, an established causative factor in the development of hypertension. The purpose of this study was to investigate the relationship between two markers of inflammation, C-reactive protein (CRP) and fibrinogen, and blood pressure (BP) and other hemodynamic variables in obese subjects.

METHODS

From a large cardiovascular study based in the general population, we selected subjects with a body mass index (BMI) > or =30 kg/m2, free of major cardiovascular diseases, not taking BP-lowering or lipid-lowering drugs (n = 487; women = 51.1%; median (5th to 95th percentile) age = 62 years (36-80)). The cardiovascular study included measurements of traditional and new risk factors, including ankle brachial BP index, a measure of subclinical atherosclerosis. CRP was determined by a high-sensitive assay.

RESULTS

In partial Spearman rank correlation analysis, adjusted for age and sex, we found no significant relationships between either CRP or fibrinogen and systolic BP, diastolic BP, pulse pressure, or ankle brachial index (rho: -0.057 to 0.068; P > 0.13). However, fibrinogen and CRP were found to be significantly related to heart rate (rho: 0.127-0.169; P < 0.01).

CONCLUSIONS

In this study of generally healthy obese subjects from the general population, we found no significant relationships between markers of inflammation and systolic BP or diastolic BP, showing that obese subjects with higher levels of inflammatory markers do not have higher BP levels than their obese counterparts with lower levels of inflammatory markers.

Androgen deficiency as a predictor of metabolic syndrome in aging men: an opportunity for intervention?

The prevalence of metabolic syndrome is increasing globally and is an important risk factor for the development of cardiovascular disease. Longitudinal population studies have found that low testosterone status in men is a risk factor for the later development of metabolic syndrome. Men with metabolic syndrome and type 2 diabetes mellitus have a higher incidence of hypotestosteronaemia. Furthermore, in men, testosterone levels are inversely associated with the degree of carotid and aortic atherosclerosis. Early interventional, short-term studies have shown that testosterone replacement therapy has a beneficial effect on visceral obesity, insulin sensitivity, glycaemic control and lipid profiles in men with diagnosed hypogonadism with and without diabetes. The effect of testosterone therapy on atherogenesis in men is unknown; however, animal studies have shown that testosterone is atheroprotective and can ameliorate the degree of atherosclerosis. Testosterone is an arterial vasodilator and has been shown to improve myocardial ischaemia in men with coronary artery disease. This review discusses the role that testosterone may play in the pathogenesis of metabolic syndrome in men and also examines the potential role of testosterone replacement therapy in this condition.

Blood coagulation and fibrinolysis in male patients with hypogonadotropic hypogonadism: plasma factor V and factor X activities increase in hypogonadotropic hypogonadism

BACKGROUND AND OBJECTIVES

In men, androgens have both pro- and anti-thrombotic effects. Androgen deficiency in men is associated with an increased incidence of cardiovascular disease (CVD). However, the influence of hypogonadism on hemostasis is controversial. Little is known about hemostatic features of male patients with idiopathic hypogonadotropic hypogonadism (IHH). Thus, the aim of the present study was to evaluate the markers of endogenous coagulation and fibrinolysis, and to investigate the relationships between endogenous sex hormones and hemostatic parameters and serum lipid profile in men with IHH.

DESIGN AND METHODS

Seventeen patients with IHH and 20 age-matched healthy controls were included in the study. Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, factors (F) V, VII, VIII, IX, and X activities, von Willebrand factor (vWF), antithrombin III (AT III), protein C, protein S, tissue plasminogen activator (t-PA), and tissue plasminogen activator inhibitor (PAI-1), as well as common lipid variables, were measured. The relationships between serum sex hormones and these hemostatic parameters were examined.

RESULTS

Compared with the control subjects, platelet count, FV, FX, and protein C activities were significantly increased in patients with IHH (p<0.01, p<0.05, p<0.01, and p<0.05, respectively), whereas AT III was decreased (p<0.05). Fibrinogen, FVIII, vWF, t-PA, PAI-1, and the other coagulation/fibrinolysis parameters and lipid profile in patients with IHH were not different from the controls. In patients with IHH, we showed that serum LH level was negatively correlated with fibrinogen (r: -0.78, p<0.01) and protein C (r: -0.55, p<0.05) and positively correlated with t-PA (r: 0.53, p<0.05). Serum FSH levels inversely correlated with fibrinogen (r: -0.75, p<0.01).

INTERPRETATION AND CONCLUSIONS

We found some differences in the hemostatic parameters between the patients with IHH and healthy controls. Increased platelet count, FV and FX activities and decreased AT III levels in patients with IHH represent a potential hypercoagulable state, which might augment the risk for atherosclerotic and atherothrombotic complications. Therefore, IHH may be associated with an increased risk of CVD. However, sex hormones may play a role at different levels of the complex hemostatic system in patients with IHH.

Physiological testosterone stimulates tissue plasminogen activator and tissue factor pathway inhibitor and inhibits plasminogen activator inhibitor type 1 release in endothelial cells

There is a striking gender difference in atherosclerotic vascular disease. For decades, testosterone was considered detrimental to the cardiovascular system. Recent studies, however, have presented some alternative results. The aim of this study was to evaluate the effect of testosterone, using physiological and supraphysiological concentrations, on antigen and mRNA levels of tissue plasminogen activator (tPA), plasminogen activator inhibitor type 1 (PAI-1), and tissue factor pathway inhibitor (TFPI) released by human umbilical vein endothelial cells and to investigate the cellular mechanism. Cells within 2-3 passages were cultured in 25 cm(2) flasks or plated onto 96-well plates with a density of about 1 x 10(5) cells/mL as recommended. The cells were incubated in the presence or absence of testosterone (3, 30, 3 x 10(3), 3 x 10(4) nmol/L) for 48 h. Levels of tPA, PAI-1, and TFPI antigen were assayed with ELISA kits. Reverse transcriptase PCR was carried out to detect tPA, PAI-1, and TFPI mRNA levels. Cells were incubated in androgen-receptor antagonist (flutamide 10 micromol/L) or aromatase inhibitor (aminoglutethimide 50 micromol/L) for 3 h, and then the experiments were repeated. Testosterone at a physiologic concentration (30 nmol/L) increased the antigen levels of tPA and TFPI significantly (P < 0.05). However, tPA and TFPI levels were markedly reduced (P < 0.05) at a larger dose (3 x 10(4) nmol/L). On the other hand, PAI-1 antigen levels decreased significantly at the testosterone concentrations ranging from 3 to 3 x 10(4) nmol/L (P < 0.05). The change in the levels of tPA and TFPI were reflected in the corresponding change in mRNA levels. Flutamide attenuated the effect of testosterone at physiological concentration (30 nmol/L). The results demonstrated that testosterone at physiological concentrations may have a beneficial influence on the haemostatic system through enhancement of anticoagulant activity, resulting from stimulation of TFPI and tPA expression and inhibition of PAI-1 secretion by the endothelium.

Testosterone and atherosclerosis in aging men: purported association and clinical implications

Two of the strongest independent risk factors for coronary heart disease (CHD) are increasing age and male sex. Despite a wide variance in CHD mortality between countries, men are consistently twice as likely to die from CHD than their female counterparts. This sex difference has been attributed to a protective effect of female sex hormones, and a deleterious effect of male sex hormones, upon the cardiovascular system. However, little evidence suggests that testosterone exerts cardiovascular harm. In fact, serum levels of testosterone decline with age, and low testosterone is positively associated with other cardiovascular risk factors. Furthermore, testosterone exhibits a number of potential cardioprotective actions. For example, testosterone treatment is reported to reduce serum levels of the pro-inflammatory cytokines interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha, and to increase levels of the anti-inflammatory cytokine IL-10; to reduce vascular cell adhesion molecule (VCAM)-1 expression in aortic endothelial cells; to promote vascular smooth muscle and endothelial cell proliferation; to induce vasodilatation and to improve vascular reactivity, to reduce serum levels of the pro-thrombotic factors plasminogen activator inhibitor (PAI)-1 and fibrinogen; to reduce low-density lipoprotein-cholesterol (LDL-C); to improve insulin sensitivity; and to reduce body mass index and visceral fat mass. These actions of testosterone may confer cardiovascular benefit since testosterone therapy reduces atheroma formation in cholesterol-fed animal models, and reduces myocardial ischemia in men with CHD. Consequently, an alternative hypothesis is that an age-related decline in testosterone contributes to the atherosclerotic process. This is supported by recent findings, which suggest that as many as one in four men with CHD have serum levels of testosterone within the clinically hypogonadal range. Consequently, restoration of serum levels of testosterone via testosterone replacement therapy could offer cardiovascular, as well as other, clinical advantages to these individuals.

Cardiovascular issues in hypogonadism and testosterone therapy

A systematic literature search was conducted to investigate the cardiovascular issues related to hypogonadism and testosterone therapy. Vascular cells contain sex steroid hormone receptors. Testosterone can exert effects on the vascular wall, either by itself or through aromatization as estrogen. Hypogonadism is associated with central obesity; insulin resistance; low levels of high-density lipoprotein (HDL); high cholesterol levels; and high levels of low-density lipoprotein (LDL), triglycerides, fibrinogen, and plasminogen activator-1. Some observational studies show a correlation between low testosterone and cardiovascular disease (CVD), and others show no correlation. Interventional studies do not reveal a direct long-term relation between testosterone therapy and CVD. Short-term data suggest cardiovascular benefits of testosterone. Testosterone therapy has beneficial and deleterious effects on cardiovascular risk factors. It improves insulin sensitivity, central obesity, and lowers total cholesterol and LDL. In some studies, testosterone therapy has an HDL-lowering effect, and in other studies this effect is insignificant. This should not be assumed to be atherogenic because it might be related to reverse cholesterol transport and effects on the HDL(3) subfraction. The cardiovascular effects of testosterone therapy may be neutral to beneficial. There is no contraindication for testosterone therapy in men with CVD and diagnosed hypogonadism with or without erectile dysfunction. Caution should be exercised regarding occasional increases in hematocrit levels, especially in patients with congestive heart failure. Conversely, evidence does not support testosterone therapy in aging men for the purpose of cardiovascular benefit, despite claims to this effect. Further research on the cardiovascular benefits and risks of testosterone is strongly recommended.

The Metabolic Syndrome and Disturbances in Hormone Levels in Long-Term Survivors of Disseminated Testicular Cancer

Purpose

The metabolic syndrome may be an important risk factor for cardiovascular disease in long-term survivors of testicular cancer (TC). We investigated the associations between hormone levels and the metabolic syndrome in these men.

Patients and Methods

We included TC patients cured by orchidectomy and cisplatin-based chemotherapy, stage I TC patients after orchidectomy only, and healthy men of comparable age. Presence of the metabolic syndrome was determined using guidelines from the National Cholesterol Education Program Adult Treatment Panel III. Thyroid-stimulating hormone, follicle-stimulating hormone (FSH), inhibin B, luteinizing hormone (LH), total testosterone, sex-hormone–binding globulin, free testosterone, estradiol, dehydroepiandrosterone sulfate, and insulin-like growth factor 1 were determined in blood. Cortisol metabolite excretion was measured in urine.

Results

Eighty-six chemotherapy patients (median follow-up, 7 years) were compared with 44 stage I patients and 47 controls. LH and FSH were higher, and inhibin B and total and free testosterone were lower in chemotherapy patients than controls. Adrenal and thyroid hormone production were unaffected. Chemotherapy patients with the metabolic syndrome (n = 22; 26%) had a higher body mass index (BMI) pretreatment, a larger BMI increase during follow-up, lower total testosterone, and higher urinary cortisol metabolite excretion than those patients without the metabolic syndrome. BMI and insulin were associated with the metabolic syndrome, while total testosterone and urinary cortisol metabolite excretion were associated with BMI.

Conclusion

We found gonadal dysfunction, but normal adrenal and thyroid function. Through its association with BMI, testosterone may play a role in the development of the metabolic syndrome in long-term TC survivors.

The aging male: testosterone deficiency and testosterone replacement. An up-date

The significance of the age-related decline of androgens remains unclear in terms of cardiovascular risk, mood and cognition, and prostatic health. Although much research has been undertaken in this area and men's health has received still more attention in the latest years, there are no data based on randomized controlled clinical studies in aging men investigating the long-term effects of androgen replacement therapy on various aspects of the cardiovascular system, the immune system, body composition, and the brain. In men receiving long-term androgen replacement therapy, the safety aspects regarding the prostate are also an area of clinical importance. In this paper we present an up-dated review of the experimental and clinical evidence of androgen deficiency and androgen replacement therapy on carbohydrate metabolism, on coagulation and fibrinolysis, inflammatory effects, effects on lipoprotein metabolism, direct arterial effects, effects on body composition, effects on cognitive function and mood, and prostatic effects. The evidence clearly shows that data for the most part are conflicting, with only very few randomized studies available.

Relationships in men of sex hormones, insulin, adiposity, and risk factors for myocardial infarction

That sex hormones, insulin, and obesity all correlate with the constellation of risk factors for myocardial infarction (MI) that has come to be known as "syndrome X," the "insulin-resistance syndrome," or the "metabolic syndrome" suggests that any one or more of them could underlie and link the risk factors to form the constellation. That sex hormones, insulin, and obesity also correlate with each other complicates their identification as an underlying link. To compare the likelihood of each being a link, we measured and determined the interrelationships of sex hormones, insulin, adiposity variables, and risk factors for MI in 80 apparently healthy men. Of the adiposity variables, visceral adipose tissue (VAT) correlated more strongly with the risk factors for MI than did body mass index (BMI), total adipose tissue (TAT), subcutaneous adipose tissue (SCAT), waist-to-hip ratio (WHR), and waist circumference (W). Controlling for VAT eliminated all of the other adiposity correlations that had been significant. VAT, therefore, was used as the measure of adiposity for further data analysis. VAT correlated more strongly with risk factors for MI than did sex hormones and insulin, and most of the correlations of sex hormones and insulin with risk factors for MI lost statistical significance after controlling for VAT. Testosterone and the ratio of estradiol-to-testosterone (E/T) correlated with insulin; on controlling for VAT, only the E/T-insulin correlation remained significant (r =.38, P <.001) and on multiple linear regression analysis, insulin was associated with estradiol (P =.01) and testosterone (P =.04) independently of VAT and age. In conclusion, (1) VAT in men may largely explain the correlations of sex hormones, insulin, and obesity with the risk factors for MI measured, (2) VAT may be the principal factor in men, independently of other measures of adiposity, that links risk factors for MI to form the constellation, and (3) estradiol may play a more important role in the sex hormone-insulin relationship in men than has generally been considered.

Androgens and coronary artery disease

A significant and independent association between endogenous testosterone (T) levels and coronary events in men and women has not been confirmed in large prospective studies, although cross-sectional data have suggested coronary heart disease can be associated with low T in men. Hypoandrogenemia in men and hyperandrogenemia in women are associated with visceral obesity; insulin resistance; low high-density lipoprotein (HDL) cholesterol (HDL-C); and elevated triglycerides, low-density lipoprotein cholesterol, and plasminogen activator type 1. These gender differences and confounders render the precise role of endogenous T in atherosclerosis unclear. Observational studies do not support the hypothesis that dehydroepiandrosterone sulfate deficiency is a risk factor for coronary artery disease. The effects of exogenous T on cardiovascular mortality or morbidity have not been extensively investigated in prospective controlled studies; preliminary data suggest there may be short-term improvements in electrocardiographic changes in men with coronary artery disease. In the majority of animal experiments, exogenous T exerts either neutral or beneficial effects on the development of atherosclerosis. Exogenous androgens induce both apparently beneficial and deleterious effects on cardiovascular risk factors by decreasing serum levels of HDL-C, plasminogen activator type 1 (apparently deleterious), lipoprotein (a), fibrinogen, insulin, leptin, and visceral fat mass (apparently beneficial) in men as well as women. However, androgen-induced declines in circulating HDL-C should not automatically be assumed to be proatherogenic, because these declines may instead reflect accelerated reverse cholesterol transport. Supraphysiological concentrations of T stimulate vasorelaxation; but at physiological concentrations, beneficial, neutral, and detrimental effects on vascular reactivity have been observed. T exerts proatherogenic effects on macrophage function by facilitating the uptake of modified lipoproteins and an antiatherogenic effect by stimulating efflux of cellular cholesterol to HDL. In conclusion, the inconsistent data, which can only be partly explained by differences in dose and source of androgens, militate against a meaningful assessment of the net effect of T on atherosclerosis. Based on current evidence, the therapeutic use of T in men need not be restricted by concerns regarding cardiovascular side effects. Available data also do not justify the uncontrolled use of T or dehydroepiandrosterone for the prevention or treatment of coronary heart disease.

Cardiovascular effects of androgens

In the process of atherosclerosis sex steroids play a complex role in the vascular vessel wall system. Although a number of experimental studies have clearly documented an atheroprotective effect of estrogens, in recent clinical studies, estrogen replacement therapy has failed to reduce cardiovascular mortality. The effects of androgens on the cardiovascular system and cardiovascular diseases are even more controversial. Whereas in the past, androgens were mainly believed to exert adverse effects on the cardiovascular system, recent studies in men have documented a number of beneficial actions of testosterone in the arterial vascular system. Androgens affect lipid metabolism (e.g., LDL and HDL cholesterol, Lp(a)) and hemostasis (e.g., platelet aggregation and fibrinolytic activity). In addition, several other physiological and pathophysiological processes in the arterial vessel wall are influenced by androgens. Acute hemodynamic effects of testosterone on coronary vasomotion and stress-test-induced ischemia were reported. Additionally, recent animal and in vitro studies have further documented an inhibitory effect of androgens on neointimal plaque formation. This review discusses different and, in part, contradictory effects of androgens on the cardiovascular system including potential signal transduction pathways in androgen target cells.

Bio-available testosterone levels fall acutely following myocardial infarction in men: association with fibrinolytic factors

The effect of acute myocardial infarction on plasma levels of testosterone in men is unclear. No previous studies have evaluated the bio-available fraction of testosterone. Low plasma testosterone levels have been associated with several risk factors for myocardial infarction, including an unfavorable fibrinolytic profile. In a prospective, case control study, we examined changes in plasma levels of sex hormones, including bio-available testosterone, in patients with acute myocardial infarction and in control subjects. In addition, changes in hormone levels in patients were compared with alterations in the fibrinolytic profile. Thirty male patients admitted with chest pain were studied. Twenty two had acute myocardial infarction and eight had non-specific chest pain. Plasma levels of total and bio-available testosterone, 17beta-estradiol, sex hormone binding globulin and insulin were measured at baseline and throughout admission. In addition, fibrinolytic factors (plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (tPA) and fibrinogen) were measured in patients who received fibrinolysis. Height and weight, and the subsequent development of heart failure or myocardial dysfunction were also recorded. Patients had lower levels of bio-available testosterone (2.07 +/- 0.75 nmol/L vs. 5.3 +/- 1.7 nmol/L, p < 0.05) and higher levels of 17beta-estradiol (87.9 +/- 39.5 pmol/L vs. 48.1 +/- 18.4 pmol/L, p < 0.001) than controls. Total and bio-available testosterone levels fell acutely following myocardial infarction (11.9 +/- 3.8 nmol/L to 9.7 +/- 3.3 nmol/L, p < 0.05; 1.95 +/- 0.76 nmol/L to 1.55 +/- 0.67 nmol/L, p < 0.05). This reduction was associated with elevation of PAI-I activity and reduction of tPA activity, independent of changes in plasma insulin levels. Patients with lower baseline levels of testosterone and higher levels of 17beta-estradiol had a relatively pro-thrombotic fibrinolytic profile and increased risk of complications. In conclusion, total and bio-available levels of testosterone fall following acute myocardial infarction in men, in association with adverse changes in fibrinolytic profile. It is not clear whether this association represents a direct effect of testosterone on thrombotic tendency but warrants further investigation.

Erythrocyte damage and leukocyte activation in ischemic stroke

BACKGROUND

The traditional lipid risk factors can only predict some of the cardiovascular events. Our work has focused on new potential biological markers of risk, namely leukocyte activation and erythrocyte membrane damage, in ischemic stroke cases.

METHODS

Besides the traditional lipid profile, we evaluated the plasma levels of elastase and lactoferrin as markers of leukocyte activation, and membrane band 3 protein profile and membrane bound hemoglobin as markers of erythrocyte damage. Total and differential leukocyte counts and erythrocyte counts, hematocrit and hemoglobin concentrations were also evaluated. The lipid study included the evaluation of triglycerides, total cholesterol, high-density lipoprotein cholesterol (HDLc), low-density lipoprotein cholesterol (LDLc), apolipoprotein AI (Apo AI) and B (Apo B), and lipoprotein (a) (Lp(a)). The work was performed in a control group (n=29) with no history of cardiovascular events, presenting normal hematological and lipid values, and in a pathologic group (n=21) of ischemic stroke cases diagnosed by computed tomographic imaging.

RESULTS

We found that ischemic stroke was associated with significantly higher values of leukocytes, which seem to be activated, as shown by significant higher levels of elastase and lactoferrin. This activation seems to impose erythrocyte damage, as suggested by a significant increase in membrane bound hemoglobin and by a different band 3 profile.

CONCLUSIONS

Our data suggest that plasma levels of elastase and lactoferrin, together with levels of erythrocyte membrane bound hemoglobin and band 3 profile, could be used as powerful new markers of risk for cardiovascular events.

The genesis of atherosclerosis and risk factors: a review

Atherosclerosis constitutes the most common medical and surgical problem. This can be manifested clinically as stroke, coronary artery disease, or peripheral vascular disease. In the present review the microscopic appearance of the normal arterial wall, the definition of atherosclerosis and the five theories of atherogenesis are described. These are: the lipid theory, the hemodynamic theory, the fibrin incrustation theory, the nonspecific mesenchymal hypothesis and the response to injury hypothesis. Based on the above theories the sequence of events in atherogenesis is analyzed. The classification of the atherosclerotic lesions according to Stary (types I-VI) and their characteristics appear in a table. The epidemiology and the role of the following risk factors are presented in detail: age, sex, lipid abnormalities, cigarette smoking, hypertension, diabetes mellitus, physical inactivity, alcohol consumption, obesity, and hemostatic factors. In addition, less common genetically determined associations like homocystinuria, Tangier disease, Hutchinson-Gilford syndrome (progeria), Werner's syndrome, radiation induced atherosclerosis and the implications of Chlamydia pneumoniae on the arterial wall are discussed.

[Coagulant activity of factor VII (FVIIc) in the elderly with ischemic heart disease]

BACKGROUND

The coagulant activity of factor VII increases with age and is a risk factor in middle aged subjects. Its role in elderly people is still unknown. The aim of this study was to evaluate whether or not FVIIc is a risk factor in such population.

PATIENTS AND METHOD

STUDY DESIGN

cases and controls study. The group of cases consisted of 79 subjects fulfilling the following criteria: a) age between 65 and 85 years, and b) admission in the Valle de los Pedroches Hospital of Pozoblanco (Córdoba, Spain) due to a myocardial infarction and/or unstable angina, 2 or 6 months before their enrollment. The control group consisted of 81 subjects of similar age, chosen at random from the municipal registry, and excluding those with coronary heart disease. Factor VIIc was measured by conventional methods. Plasma samples were diluted with deficient plasma in FVIIc, and coagulation times were measured after adding thromboplastin and calcium. The measures were compared with a <<control>> plasma and the results were presented as a percentage.

RESULTS

There were no significant differences in the FVIIc between cases (118.3 [SD 22.2]) and controls (116.5 [24.4]; p = 0.630) in the total group. When classified according to their age, it was observed that within the group of more than 75 years old, cases had a higher FVIIc than controls (124.1 [18.2] vs 113.3 [23.5]; p < 0. 05). When the classification was carried out according to sex, male presented similar results than the total group. Bivariable analysis showed, in subjects with coronary diseases, that FVIIc was related to total cholesterol, cLDL, apoprotein B, body mass index, HbA1c, and age. Factors related to FVIIc in the multivariable analysis were basal glucose serum level, body mass index; cHDL was negatively related.

CONCLUSIONS

FVIIc is higher in very old subjects with coronary diseases so it may be a significant coronary risk factor in this age group.

Plasma fibrinogen and incident hypertension in the Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

Several cross-sectional studies have reported a positive association between plasma fibrinogen levels and prevalent hypertension. Other studies have reported a positive association between hypertension and whole-blood or plasma viscosity, to which fibrinogen contributes. To our knowledge, there has been no prospective study of fibrinogen and incident hypertension.

SUBJECTS AND METHODS

We measured plasma fibrinogen levels in a population-based cohort study of middle-aged adults and related it to the occurrence of incident hypertension (systolic blood pressure > or = 140 mmHg or diastolic blood pressure > or = 90 mmHg or use of antihypertensive medication) over 6 years.

RESULTS

There was a moderately strong positive association between fibrinogen levels and prevalent hypertension in both men and women, with the odds of hypertension elevated by 50% for the highest fibrinogen quartile versus the lowest. Among 7884 participants at risk, 1609 developed hypertension over 6 years. Adjusted for age, race, field center and baseline systolic blood pressure, the odds ratio of incident hypertension in relation to fibrinogen quartiles was 1.0, 1.07, 1.21 and 1.43 in men (P= 0.003 for trend) and 1.0, 0.92, 0.99 and 0.99 in women (P= 0.89 for trend). After adjustment for other risk factors, the odds ratios were 1.0, 1.03, 1.15 and 1.29 (P= 0.045 for trend) in men and remained nonsignificant in women.

CONCLUSIONS

Despite a moderately strong positive association between fibrinogen levels and prevalent hypertension in both sexes, there was only a weak positive association between fibrinogen levels and incident hypertension in men and no association in women. Whether an elevated fibrinogen level is a risk factor for, or a consequence of, hypertension remains unclear.

Effects of doxazosin and atenolol on atherothrombogenic risk profile in hypertensive middle-aged men

The alpha-blockers prazosin and doxazosin reduce hypertriglyceridemia (HTG) and increase serum levels of high-density lipoprotein (HDL)-cholesterol, whereas beta-blockers such as atenolol have the opposite effect. As HTG is associated with reduced fibrinolysis and hypercoagulability, we investigated the effects of doxazosin and atenolol on serum lipids and hemostatic factors in hypertensive men with an atherothrombogenic risk profile. The study was randomized and open, but blinded to investigator of biochemical results. Forty-five men (mean age, 44.5 years) with central obesity [median body-mass index (BMI), 28 kg/m2] and moderate hypertension [median diastolic blood pressure (DBP), 104.5 mm Hg] were treated with atenolol (n = 22) or doxazosin (n = 23) for 22 weeks, after which changes in between-group differences from baseline were estimated. After intervention, significant between-group differences in favor of doxazosin were found: lower triglycerides (p = 0.008) and higher HDL cholesterol (p = 0.036); furthermore, improvement of fibrinolysis: lower plasminogen activator inhibitor-1 (PAI-1) activity (p = 0.012), higher tissue plasminogen activator (tPA) activity after venous occlusion (VO); and higher levels of serum D-dimer, both unstimulated (p = 0.0016) and after VO (p = 0.0032). In addition, lower levels of serum testosterone were found in the atenolol group (p = 0.0016). A profile with reduced HTG, increased HDL cholesterol, and improved fibrinolysis was obtained with doxazosin when compared with atenolol. Furthermore, the observed decrease in serum testosterone on atenolol treatment would rather favor long-term treatment with doxazosin in this study population.

The 4G/5G polymorphism of the plasminogen activator inhibitor gene is associated with the time course of progression to acute coronary syndromes

The 4G allele of the plasminogen activator inhibitor (PAI-I) gene is associated with increased PAI-I levels. Increased PAI-I levels have been reported to be associated with atherothrombotic events. However, the significance of the 4G/5G polymorphism of the PAI-I gene in the pathogenesis of ischemic heart diseases has not been determined. We assessed the 4G/5G polymorphism of the PAI-I gene in 500 subjects including 148 normal controls, 23 subjects with normal coronary arteries, 28 subjects with a paradoxical acetylcholine response, 97 subjects with angina pectoris (AP) and 204 subjects with myocardial infarction (MI). We assessed the length of time between the first anginal pain and the onset of acute coronary syndromes (ACS) in the AP and MI subjects. Subjects who developed ACS within 2 months from the first anginal pain were categorized to have a rapid progression to ACS, and subjects who had had stable anginal pain more than 2 months were placed in the non-ACS group. Subjects in the ACS group were younger than those in non-ACS group (P = 0.012) The frequency of the 5G/5G genotype of the PAI-I gene was lower in the ACS (0.228) than in the non-ACS group (0.093) (P = 0.003). Multiple logistic analyses revealed that a younger age (P = 0.028, odds ratio = 1.03) and the (4G/5G + 4G/4G) genotype of the PAI-I gene (P = 0.008, odds ratio = 2.68) were associated with the ACS group. We also assessed plasma PAI-I antigen levels in 78 subjects. Plasma PAI-I antigen levels in the non-ACS group were significantly lower than those in the ACS group (P = 0.050). Multiple regression analyses revealed that plasma PAI-I levels were determined by plasma insulin (P < 0.001) and the genotype of the PAI-I gene (P = 0.019). Higher plasma insulin levels and the (4G/5G + 4G/4G) genotype of the PAI-I gene were associated with higher plasma PAI-I levels. The 4G/5G polymorphism of the PAI-I gene influenced not only plasma PAI-I antigen levels but also the time course of the progression to ACS in patients with coronary atherosclerosis.

Lower androgenicity is associated with higher plasma levels of prothrombotic factors irrespective of age, obesity, body fat distribution, and related metabolic parameters in men

The purpose of this study was to examine the relationships between androgenic status and plasma levels of both prothrombotic and antithrombotic factors in men, irrespective of obesity, body fat distribution, and metabolic parameters. Sixty-four apparently healthy men, 40 with a body mass index (BMI) greater than 25 kg/m2 (overweight and obese [OO]) and 24 non-obese controls with a BMI less than 25, were selected and evaluated for (1) plasma concentrations of plasminogen activator inhibitor-1 (PAI-1) antigen, PAI-1 activity, fibrinogen, von Willebrand factor (vWF) antigen, vWF activity, and factor VII (FVII) as the prothrombotic factors; (2) plasma levels of tissue plasminogen activator (TPA) antigen, protein C, and antithrombin III as the antithrombotic factors; (3) fasting plasma concentrations of insulin and glucose and the lipid pattern (triglycerides [TG] and total and high-density lipoprotein [HDL] cholesterol) as the metabolic parameters; and (4) free testosterone (FT), dehydroepiandrosterone sulfate (DHEAS), and sex hormone-binding globulin (SHBG) serum levels as the parameters of androgenicity. Body fat distribution was evaluated by the waist to hip ratio (WHR). In OO and non-obese subjects taken together, plasma levels of PAI-1 antigen, fibrinogen, and FVII were inversely associated with FT (r = .255, P < .05, r = -3.14, P < .05, and r = -.278, P < .05, respectively), and the negative relationships of both fibrinogen and FVII with FT were maintained after stepwise multiple regression analysis. Plasma concentrations of PAI-1 antigen and PAI-1 activity were also negatively correlated with SHBG (r = -.315, P < .05 and r = -.362, P < .01, respectively), and these associations held irrespective of the other parameters investigated. None of the antithrombotic and fibrinolytic factors were independently related to serum androgen levels. Subjects with a BMI higher than 25 kg/m2 had higher plasma concentrations of PAI-1 antigen, PAI-1 activity, and fibrinogen as compared with non-obese controls (P < .001, P < .001, and P < .01, respectively). In addition, in OO and control subjects as a whole, multiple stepwise regression analysis showed that the associations of BMI with PAI-1 activity, fibrinogen, vWF antigen, and vWF activity were independent of any other metabolic and hormonal parameters. Plasma concentrations of PAI-1 antigen, PAI-1 activity, and fibrinogen were also directly correlated with WHR in all subjects taken together, irrespective of the other parameters investigated. Evaluation of antithrombotic factors showed that OO subjects had higher TPA plasma concentrations than non-obese controls (P < .001), whereas protein C and antithrombin III did not differ in the two groups. TPA was also directly correlated with BMI (r = .415, P < .001) and WHR (r = .393, P < .001) in all subjects. The results of this study indicate that (1) men with lower FT serum levels have higher fibrinogen and FVII plasma concentrations, and those with lower SHBG serum levels also have higher levels of PAI-1 antigen and activity; (2) irrespective of other factors, obesity per se may account for higher concentrations of PAI-1, fibrinogen, and vWF; (3) plasma levels of PAI-1 (antigen and activity) and fibrinogen correlate independently with WHR; and (4) among the investigated antithrombotic factors (TPA antigen, protein C, antithrombin III), only TPA antigen plasma concentrations are higher in men with abdominal obesity. Thus, because of the increase in several prothrombotic factors, men with central obesity, particularly those with lower androgenicity, seem to be at greater risk for coronary heart disease (CHD). Apparently, this risk is not counteracted by a parallel increase in plasma concentrations of antithrombotic factors.

The relationship of natural androgens to coronary heart disease in males: a review

Published studies dealing with the relationship between circulating levels of testosterone and dehydroepiandrosterone (sulfate) (DHEA(S)) and coronary heart disease (CHD) in males, as well as corresponding experimental animal studies are reviewed. One randomized intervention study, eight prospective and 30 cross-sectional studies have evaluated this relationship. In the intervention study, testosterone undecanoate given orally significantly improved angina pectoris in 62 patients with CHD as compared to placebo. No significant association between serum testosterone and CHD was reported in the prospective studies, whereas those studies concerning DHEAS found either no or an inverse association with CHD. Of 30 cross-sectional studies, 18 reported reduced concentrations of testosterone (primarily), and/or DHEA(S) in CHD patients as compared to normals, 11 found similar circulating levels of these androgens in controls and patients with CHD, and one study found elevated levels of DHEA(S) in patients. Animal studies (six male rabbits and one in male chicks) suggest an anti-atherogenic effect of testosterone and DHEA. In conclusion, one intervention, eight cohort and several cross-sectional studies suggest either a neutral or a favourable effect of testosterone and DHEA(S) on CHD in males.

Altered erythrocyte membrane band 3 profile as a marker in patients at risk for cardiovascular disease

The aim of this study is to evaluate the correlation between a rise in blood neutrophil concentration and cellular and molecular changes of erythrocytes, among populations presenting an increased risk of cardiovascular disease (CVD). A population of men aged 20-65 years was used which included 22 post-myocardial infarction individuals (< 48 h), 24 survivors of myocardial infarction (> 3 months), 12 hypertensive individuals and 29 individuals presenting normal haematological values and normal lipid profile. The lipid profile parameters used to ascertain increased risk of CVD included triglycerides (TG), total cholesterol (Chol), high-density lipoprotein cholesterol (HDLc), low-density lipoproteins cholesterol (LDLc) and apolipoproteins A1 (Apo A1) and B (Apo B). The hematological parameters measured were concentration of total white blood cells (WBC) and of the several leukocyte types; concentration of red blood cells (RBC); hematocrit (Ht); hemoglobin concentration (Hb); mean cell volume (MCV); activity of erythrocyte glucose-6-phosphate dehydrogenase (G6PD); band 3, its aggregates and fragments in erythrocyte membranes, the percentage of membrane-bound hemoglobin (MBH), and the linkage of immunoglobulin G (IgG) to erythrocyte membrane. We found that the MBH and the band 3 profile is different in control as compared to pathological groups and that, as expected, the aggregation of band 3 promotes the linkage of IgG to the erythrocyte membrane. A negative correlation was shown between total neutrophils and both total RBCs and erythrocyte G6PD activity. We suggest that the erythrocyte, a cell that undergoes and accumulates oxidative and proteolytic damage along its life span, may provide a useful model of oxidative and proteolytic stress in CVD and that band 3 may represent a useful marker of that stress.

Fibrinolysis and atherosclerosis

The link between impaired fibrinolytic function and CHD has been reinforced considerably in the past couple of years. This has been achieved by a combination of epidemiological, clinical, cell biological and molecular biological studies. The molecular mechanisms for the identified associations between more established risk factors for atherosclerotic disease and impaired fibrinolytic function now need to be disentangled to promote the design of specific drugs that may pave the way for intervention. The possibility that some of the observed relations are epiphenomena should also not be disregarded. The concept of genotype-specific differences in the susceptibility of the individual to common metabolic disturbances needs to be examined in greater detail. Basic research on the role of fibrinolysis in atherosclerosis and its thrombotic complications should be given high priority, because the modulation of fibrinolytic function is likely to become an important approach to prevention.