Effects of dehydroepiandrosterone replacement on vascular function in primary and secondary adrenal insufficiency: a randomized crossover trial

Androgen deficiency in hypopituitary women: its consequences and management

Women with hypopituitarism have various degrees of androgen deficiency, which is marked among those with combined hypogonadotrophic hypogonadism and secondary adrenal insufficiency. The consequences of androgen deficiency and the effects of androgen replacement therapy have not been fully elucidated. While an impact of androgen deficiency on outcomes such as bone mineral density, quality of life, and sexual function is plausible, the available evidence is limited. There is currently no consensus on the definition of androgen deficiency in women and it is still controversial whether androgen substitution should be used in women with hypopituitarism and coexisting androgen deficiency. Some studies suggest beneficial clinical effects of androgen replacement but data on long-term benefits and risk are not available. Transdermal testosterone replacement therapy in hypopituitary women has shown some positive effects on bone metabolism and body composition. Studies of treatment with oral dehydroepiandrosterone have yielded mixed results, with some studies suggesting improvements in quality of life and sexual function. Further research is required to elucidate the impact of androgen deficiency and its replacement treatment on long-term outcomes in women with hypopituitarism. The lack of transdermal androgens for replacement in this patient population and limited outcome data limit its use. A cautious and personalized treatment approach in the clinical management of androgen deficiency in women with hypopituitarism is recommended while awaiting more efficacy and safety data.

Low serum dehydroepiandrosterone levels are associated with diabetic retinopathy in patients with type 2 diabetes mellitus

AIMS

This cross-sectional study assessed the association of serum dehydroepiandrosterone levels with the risk of diabetic retinopathy in patients with type 2 diabetes mellitus in China.

MATERIALS AND METHODS

Patients with type 2 diabetes mellitus were included in a multivariate logistic regression analysis to assess the association of dehydroepiandrosterone with diabetic retinopathy after adjusting for confounding factors. A restricted cubic spline was also used to model the association of serum dehydroepiandrosterone level with the risk of diabetic retinopathy and to describe the overall dose-response correlation. Additionally, an interaction test was conducted in the multivariate logistic regression analysis to compare the effects of dehydroepiandrosterone on diabetic retinopathy among age, sex, obesity status, hypertension, dyslipidemia, and glycosylated hemoglobin level subgroups.

RESULTS

In total, 1,519 patients were included in the final analysis. Low serum dehydroepiandrosterone was significantly associated with diabetic retinopathy in patients with type 2 diabetes mellitus after adjustment for confounding factors (odds ratio [quartile 4 vs quartile 1]: 0.51; 95% confidence interval: 0.32-0.81; P = 0.012 for the trend). Additionally, the restricted cubic spline indicated that the odds of diabetic retinopathy decreased linearly as the dehydroepiandrosterone concentration increased (P-overall = 0.044; P-nonlinear = 0.364). Finally, the subgroup analyses showed that the dehydroepiandrosterone level stably affected diabetic retinopathy (all P for interaction >0.05).

CONCLUSIONS

Low serum dehydroepiandrosterone levels were significantly associated with diabetic retinopathy in patients with type 2 diabetes mellitus, suggesting that dehydroepiandrosterone contributes to the pathogenesis of diabetic retinopathy.

Central adrenal insufficiency: who, when, and how? From the evidence to the controversies - an exploratory review

Central adrenal insufficiency (CAI) is a life-threatening disorder. This occurs when ACTH production is insufficient, leading to low cortisol levels. Since corticosteroids are crucial to many metabolic responses under organic stress and inflammatory conditions, CAI recognition and prompt treatment are vital. However, the diagnosis of CAI is challenging. This is not only because its clinical presentation is usually oligosymptomatic, but also because the CAI laboratory investigation presents many pitfalls. Thus, the clarification of when to use each test could be helpful in many contexts. The CAI challenge is also involved in treatment: Several formulations of synthetic steroids exist, followed by the lack of a biomarker for glucocorticoid replacement. This review aims to access all available literature to synthesize important topics about who should investigate CAI, when it should be suspected, and how CAI must be treated.

Low Serum Dehydroepiandrosterone Is Associated With Diabetic Kidney Disease in Men With Type 2 Diabetes Mellitus

Background

The associations of dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) with diabetic kidney disease (DKD) remained unclear. Thus, this cross-sectional study aimed to explore the associations of DHEA and DHEAS with the risk of DKD in patients with T2DM.

Methods

The information of 1251 patients with T2DM were included in this study. Serum DHEA and DHEAS were quantified using liquid chromatography-tandem mass spectrometry assays. Multivariate logistic regression analyses were used to assess the associations of DHEA and DHEAS with DKD as well as high urine albumin to creatinine ratio (ACR).

Results

In men with T2DM, the risk of DKD decreased with an increasing DHEA concentration after adjustment for traditional risk factors; the fully adjusted OR (95% CI) for tertile3 vs tertile1 was 0.37 (0.19-0.70; P = 0.010 for trend). Similarly, when taking high ACR as the outcome, low DHEA levels were still significantly associated with increased odds of high ACR (OR, 0.37; 95% CI, 0.19-0.72 for tertile3 vs tertile1; P = 0.012 for trend). The restricted cubic spline showed that the risk of DKD gradually decreased with the increment of serum DHEA levels (P-overall = 0.007; P-nonlinear = 0.161). DHEAS was not independently associated with the risk of DKD in men. In contrast, no significant relationships were found between DHEA and DHEAS and the risk of DKD in women (all P > 0.05).

Conclusions

In men with T2DM, low serum DHEA levels were independently related to the risk of DKD after adjustment for traditional risk factors. Our finding highlights the potential role of DHEA in the development of DKD in men with T2DM.

The role for long-term use of dehydroepiandrosterone in adrenal insufficiency

PURPOSE OF REVIEW

Dehydroepiandrosterone (DHEA) is an androgen produced by the zona reticularis of the adrenal gland. Patients with adrenal insufficiency will have a deficiency of DHEA. Unlike glucocorticoid and mineralocorticoid replacement, DHEA supplementation is not considered essential for life and is therefore not routinely replaced in adrenal failure. DHEA deficiency is associated with morbidity, including adverse impacts on metabolic function, quality of life and sexuality in multiple studies. The role for replacement, however, remains unclear.

RECENT FINDINGS

The benefits of DHEA supplementation have been definitively demonstrated in a number of historical studies of patients with primary and secondary adrenal insufficiency. Beneficial impacts on quality of life, body composition, bone health and metabolic markers have been demonstrated. However, published data are inconsistent; controversies persist around the exact role of DHEA replacement and around which patient cohorts are most likely to benefit. There is also a paucity of recent randomized controlled trials in the medical literature to inform on optimal dose and duration of DHEA replacement in adrenal failure.

SUMMARY

Here, we review the evidence for DHEA supplementation in patients with adrenal insufficiency. We highlight knowledge gaps in the medical literature and areas that should be prioritized for future research endeavours.

Low Serum Dehydroepiandrosterone and Dehydroepiandrosterone Sulfate Are Associated With Coronary Heart Disease in Men With Type 2 Diabetes Mellitus

AIMS

Sex hormones play an important role in the pathogenesis of cardiovascular disease (CVD). This cross-sectional study aimed to explore the associations of dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) with coronary heart disease (CHD) and stroke in middle-aged and elderly patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

A total of 995 patients with T2DM were included in the study analysis. Serum levels of DHEA and DHEAS were quantified using liquid chromatography-tandem mass spectrometry. Binary logistic regression analyses were performed to assess the associations of DHEA and DHEAS with CHD and stroke. Receiver operating characteristic (ROC) curve analysis was performed to determine the optimal DHEA and DHEAS cutoff values for the detection of CHD in men with T2DM.

RESULTS

In men with T2DM, after adjustment for potential confounders in model 3, the risk of CHD decreased with an increasing serum DHEA level [odds ratio (OR) = 0.38, quartile 4 vs. quartile 1; 95% confidence interval (CI) = 0.16-0.90; p = 0.037 for trend). Consistently, when considered as a continuous variable, this association remained significant in the fully adjusted model (OR = 0.59, 95% CI = 0.40-0.87, p < 0.05). When taken as a continuous variable in model 3, serum DHEAS level was also inversely related to the risk of CHD among men (OR = 0.56, 95% CI = 0.38-0.82, p < 0.05). Similarly, this relationship remained statistically significant when DHEAS was categorized into quartiles (OR = 0.27, quartile 4 vs. quartile 1; 95% CI = 0.11-0.67; p = 0.018 for trend). ROC curve analyses revealed that the optimal cutoff values to detect CHD in men with T2DM were 6.43 nmol/L for DHEA and 3.54 μmol/L for DHEAS. In contrast, no significant associations were found between DHEA and DHEAS on the one hand and stroke on the other in men and women with T2DM (all p > 0.05).

CONCLUSIONS

Serum DHEA and DHEAS were significantly and negatively associated with CHD in middle-aged and elderly men with T2DM. This study suggests potential roles of DHEA and DHEAS in CHD pathogenesis.

Sex-Specific Risk of Cardiovascular Disease in Autoimmune Addison Disease-A Population-Based Cohort Study

CONTEXT

Little is known of cardiovascular disease (CVD) in autoimmune Addison disease (AAD). Inadequate glucocorticoid replacement might potentially increase CVD risk.

OBJECTIVE

To examine CVD in AAD in subgroups of ischemic heart disease (IHD) and cerebrovascular disease (CeVD) and investigate the effects of glucocorticoid and mineralocorticoid dosing.

DESIGN, SETTING, AND PATIENTS

In this cohort-control study, we used Swedish health registries from 1964 to 2013 to identify 1500 subjects with AAD and 13,758 matched controls. Incident CVD was analyzed from 2006 to 2013. Adjusted hazard ratios (aHRs) were calculated using Cox proportional hazard models. Glucocorticoid and mineralocorticoid doses were stratified to examine dose-related risks.

RESULTS

During 8807 person-years (PY), 94 events of first CVD (10.7/1000 PY) in patients with AAD occurred compared with 563 events during 80,163 PY (7.0/1000 PY) in controls. IHD was significantly more common in women (aHR, 2.15; 95% CI, 1.49 to 3.10) but not men (aHR, 1.16; 95% CI, 0.75 to 1.78) with AAD compared with controls. No increase in CeVD risk was detected (aHR, 0.88; 95% CI, 0.56 to 1.37, women; aHR, 0.88; 95% CI 0.53 to 1.50, men). CVD was associated with greater glucocorticoid and mineralocorticoid replacement doses in women but not men.

CONCLUSION

The risk of IHD but not CeVD is increased in AAD, especially in women. The risk of CVD independently correlated with greater glucocorticoid and mineralocorticoid replacement doses in women. Our data suggest that close monitoring and early treatment of risk factors for CVD, among women in particular, might be warranted.

Androgens and cardiovascular disease in women and men

Cardiovascular disease is the leading cause of death in both women and men. Its pathogenesis is multifactorial, with sex hormones playing an important role. Androgens have both direct and indirect effects on the vasculature. This review summarizes evidence on the association of both endogenous and exogenous androgens with subclinical and overt cardiovascular disease in women and men. Concerning women, both high and low levels of endogenous androgens have been associated with cardiovascular disease, while other studies have reported no association. Adiposity, impaired glucose metabolism, dyslipidemia and estrogen levels may mediate the observed associations. Regarding testosterone therapy in women, there have been no large prospective studies on cardiovascular outcomes. Concerning men, most studies indicate that low levels of circulating testosterone are associated with increased rates of cardiovascular disease in the general population; the causality, however, of this association remains to be proven. Testosterone replacement therapy in men with symptoms of hypogonadism and low serum testosterone merits caution with regard to cardiovascular safety, as evidence is still conflicting.

Effects of DHEA on metabolic and endocrine functions of adipose tissue

Dehydroepiandrosterone (DHEA) and its sulfate ester, DHEAS, are the major circulating adrenal steroids and serve as substrates for sex hormone biosynthesis. DHEA is effectively taken up by adipose tissue, where the concentrations of free DHEA are four to ten times higher than those found in the circulation. DHEA reduces adipose tissue mass and inhibits the proliferation and differentiation of adipocytes; it may also protect against obesity by lowering the activity of stearoyl-CoA desaturase 1 in fat cells. Recent studies demonstrate that DHEA stimulates triacylglycerol hydrolysis in adipose tissue by increasing the expression and activity of adipose triglyceride lipase and hormone-sensitive lipase, the key enzymes of lipolysis. DHEA has been shown to modulate insulin signaling pathways, enhance glucose uptake in adipocytes, and increase insulin sensitivity in patients with DHEA deficiency or abnormal glucose tolerance. Additionally, by suppressing the activity of 11β-hydroxysteroid dehydrogenase 1 in adipocytes, DHEA may promote intra-adipose inactivation of cortisol to cortisone. Several studies have demonstrated that DHEA may also regulate the expression and secretion of adipokines such as leptin, adiponectin, and resistin. The effects of DHEA on adipokine expression in adipose tissue are depot-specific, with visceral fat being the most responsive. The mechanisms underlying DHEA actions in adipose tissue are still unclear; however, they involve nuclear receptors such as androgen receptor and peroxisome proliferator-activated receptors γ and α. Because clinical trials investigating the effects of DHEA failed to yield consistent results, further studies are needed to clarify the role of DHEA in the regulation of human adipose tissue physiology.

Genetics of androgen metabolism in women with infertility and hypoandrogenism

Hypoandrogenism in women with low functional ovarian reserve (LFOR, defined as an abnormally low number of small growing follicles) adversely affects fertility. The androgen precursor dehydroepiandrosterone (DHEA) is increasingly used to supplement treatment protocols in women with LFOR undergoing in vitro fertilization. Due to differences in androgen metabolism, however, responses to DHEA supplementation vary between patients. In addition to overall declines in steroidogenic capacity with advancing age, genetic factors, which result in altered expression or enzymatic function of key steroidogenic proteins or their upstream regulators, might further exacerbate variations in the conversion of DHEA to testosterone. In this Review, we discuss in vitro studies and animal models of polymorphisms and gene mutations that affect the conversion of DHEA to testosterone and attempt to elucidate how these variations affect female hormone profiles. We also discuss treatment options that modulate levels of testosterone by targeting the expression of steroidogenic genes. Common variants in genes encoding DHEA sulphotransferase, aromatase, steroid 5α-reductase, androgen receptor, sex-hormone binding globulin, fragile X mental retardation protein and breast cancer type 1 susceptibility protein have been implicated in androgen metabolism and, therefore, can affect levels of androgens in women. Short of screening for all potential genetic variants, hormonal assessments of patients with low testosterone levels after DHEA supplementation facilitate identification of underlying genetic defects. The genetic predisposition of patients can then be used to design individualized fertility treatments.

Association of sex hormones with carotid artery distensibility in men and postmenopausal women: multi-ethnic study of atherosclerosis

The decline in carotid distensibility with age is steeper in women than in men, however, the correlates of this sex difference are not known. We examined the association of bioavailable testosterone, estradiol, dehydroepiandrosterone, and sex hormone-binding globulin, in 2783 postmenopausal women and 2987 men aged 45 to 84 years at the Multi-Ethnic Study of Atherosclerosis baseline examination. Carotid artery lumen diameters by ultrasound and brachial artery blood pressures were measured at systole and diastole. Regression models to determine the association of carotid distensibility coefficient and lumen diameter with sex-specific quartiles of sex hormones were adjusted for age, race, height, weight, diabetes mellitus, current smoking, antihypertensive medication use, total and high-density lipoprotein cholesterol levels, and hormone replacement therapy in women. A higher DC indicates a more distensible vessel. In women, higher dehydroepiandrosterone (P=0.008) and lower sex hormone-binding globulin (P=0.039) were associated with lower distensibility; higher dehydroepiandrosterone and lower estradiol were associated with smaller carotid diameters. In men, higher Bio-T (P=0.009) and lower estradiol (P=0.007) were associated with greater distensibility and also with smaller diameters (P=0.012 and 0.002, respectively). An androgenic internal milieu is associated with lesser carotid distensibility and diameter remodeling in women, but the opposite is true for men. Higher levels of estradiol are associated with smaller carotid diameters in both the sexes. Future longitudinal and experimental studies are needed to reveal the mechanism and clinical consequences of these associations.

Steroid replacement in primary adrenal failure does not appear to affect circulating adipokines

Despite continuous efforts for an optimal steroid replacement, recent observations suggest increased cardiometabolic risk and related mortality in primary adrenal insufficiency (PAI). Adipokines are peptides from the adipose tissue, markers of cardiometabolic dysfunction. This study was aimed to evaluate serum levels of adipokines: leptin, adiponectin, and resistin in PAI during conventional steroid substitution. The analysis comprised 63 patients (mean age 42.7 ± 14.1 years) and 63 healthy controls. Serum adipokines, lipid profile, and plasma glucose were assessed in both cohorts. ACTH, serum insulin, HOMA-IR, DHEA-S, cortisol and 24 h urinary free cortisol were determined in PAI. Body mass composition was analyzed by Dual-Energy X-ray Absorptiometry. Mean BMI in the control group was 24.1 ± 3.9 kg/m(2) and 23.7 ± 3.9 kg/m(2) in the PAI cohort. Serum leptin and adiponectin levels were similar in both groups, whereas resistin appeared significantly lower among affected subjects (p = 0.0002). Its levels were weakly correlated with HOMA-IR (p = 0.048). Leptin was independently correlated with fasting insulin, HOMA-IR, BMI, and body fat (p < 0.001). At the multiple regression analysis only weight (p = 0.017), total and HDL cholesterol (p < 0.001) appeared significant predictors of adiponectin level. No adipokine correlations with serum cortisol or daily hydrocortisone dose were found. Patients receiving DHEA substitution displayed lower leptin and adiponectin levels (p < 0.05). In conclusion, our study did not provide evidence of an adverse adipokine profile in patients with PAI under conventional glucocorticoid replacement. Serum adipokines in treated PAI follow similar correlations to those reported in healthy subjects. Further prospective studies are warranted to verify and explain plausible excess of cardiovascular mortality in PAI.

Is DHEA replacement beneficial in chronic adrenal failure?

Although dehydroepiandrosterone (DHEA) and its sulphate ester dehydroepiandrosterone sulphate (DHEAS) are the most abundant steroid hormones in the human circulation, its exact physiological role is not yet fully understood. In patients with adrenal insufficiency, secretion of DHEA is impaired, leading to decreased circulating DHEA and DHEAS levels, and to androgen deficiency in women. Replacement of DHEA in patients with adrenal insufficiency positively influence mood, sexuality and subjective health status. These effects are generally moderate and show high inter-individual variability. Limited evidence exists for immunomodulatory effects of DHEA. Although an increase of IGF-I levels has been documented, relevant effects on body composition, metabolic or cardiovascular parameters has not been observed in patients with adrenal insufficiency receiving DHEA. Larger-scale phase III studies are still lacking; therefore, initiation of DHEA replacement is decided on an individual basis, focussing on those patients with impaired well-being associated with signs and symptoms of androgen deficiency.

DHEA and mortality: what is the nature of the association?

Although very little is known about the importance of dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEA-S) in human physiology and pathophysiology, emerging observations imply pivotal roles of DHEA/-S. One such observation is the association between serum DHEA/-S levels and mortality risk. In this review, we focus on the literature addressing DHEA/-S and mortality with the aim to describe and discuss patterns and potential underlying mechanisms. Although the literature reports somewhat inconsistent results, we conclude that several larger population-based studies support an association between low DHEA/-S and risk of death, at least in elderly men. In women, the association may not be present; alternatively, there may be a U-shaped association. In men, most available evidence suggests an association with cardiovascular (CV) mortality rather than cancer mortality. Further, there are biologically plausible mechanisms for an effect of DHEA/-S on the development of CV disease. On the other hand, there is also strong evidence supporting that any disease may lower DHEA/-S. Thus, the cause-effect relation of this association is less clear. Future studies may employ a mendelian randomization approach using genetic determinants of DHEA-S levels as predictors of clinical outcomes, to delineate the true nature of the association between DHEA/-S and mortality.

A review of age-related dehydroepiandrosterone decline and its association with well-known geriatric syndromes: is treatment beneficial?

Dehydroepiandrosterone (DHEA) and its sulfate ester are the most abundant steroids in humans. DHEA levels fall with age in men and women, reaching values sometimes as low as 10%-20% of those encountered in young individuals. This age-related decrease suggests an "adrenopause" phenomenon. Studies point toward several potential roles of DHEA, mainly through its hormonal end products, making this decline clinically relevant. Unfortunately, even if positive effects of DHEA on muscle, bone, cardiovascular disease, and sexual function seem rather robust, extremely few studies are large enough and/or long enough for conclusions regarding its effects on aging. Moreover, because it has been publically presented as a "fountain of youth" equivalent, over-the-counter preparations lacking pharmacokinetic and pharmacodynamic data are widely used worldwide. Conceptually, supplementing a pre-hormone is extremely interesting, because it would permit the human organism to adequately use it throughout long periods, increasing or decreasing end products according to his needs. Nevertheless, data on the safety profile of long-term DHEA supplementation are still lacking. In this article, we examine the potential relation between low DHEA levels and well-known age-related diseases, such as sarcopenia, osteoporosis, dementia, sexual disorders, and cardiovascular disease. We also review risks and benefits of existing protocols of DHEA supplementation.

Cardiovascular risk factors in patients with Addison's disease: a comparative study of South African and Swedish patients

BACKGROUND

Patients with Addison's disease (AD) in Scandinavia have an increased risk for premature death due to cardiovascular disease (CVD). Serum lipids are important risk factors for CVD and vascular mortality. Replacement doses of hydrocortisone have historically been higher in Sweden than South Africa. The primary aim was to study the lipid profiles in a large group of patients with AD with the hypothesis that the lipid profile in patients in Sweden would be worse than in South Africa.

METHODS

In a cross-sectional study, 110 patients with AD (55 from South Africa, 55 from Sweden) matched for age, gender, ethnicity and BMI were studied. Anthropometric measures, blood pressure, lipids, highly sensitive C-reactive protein (hs-CRP) and adiponectin were studied.

RESULTS

All patients were Caucasian and the majority were women N = 36 (65.5%). Mean (standard deviation; SD) ages of the Swedish and South African patients were 52.9 (13.0) and 52.6 (14.4) years and BMI 25.3 (3.2) and 25.8 (4.1) kg/m2, respectively. The mean total daily hydrocortisone dose was greater in the Swedish patients than the South African patients, [33.0 (8.1) versus 24.3 (8.0) mg; p<0.0001]. South African patients had higher median (interquartilerange; IQR) triglycerides (TG) [1.59 (1.1-2.46) versus 0.96 (0.74-1.6) mmol/l; p<0.001], total cholesterol (TC) [6.02(1.50) versus 5.13 (0.87) mmol/l; p<0.001], LDL-C [4.43 (1.44) versus 2.75 (0.80) mmol/l; p<0.001] and median hs-CRP [2.15 (0.93-5.45) versus 0.99 (0.57-2.10) mg/L; p<0.003] and lower HDL-C [0.80 (0.40) versus 1.86 (0.46) mmol/l; p<0.001] than the Swedish patients. Approximately 20% of the patients in both cohorts had hypertension and diabetes mellitus.

CONCLUSIONS

South African patients with AD have worse lipid profiles and higher hs-CRP compared to their matched Swedish patients, despite lower doses of hydrocortisone. It is uncertain at this time whether these are due to genetic or environmental factors.

Ablation of the androgen receptor gene modulates atrial electrophysiology and arrhythmogenesis with calcium protein dysregulation

Androgen deficiency is important in the pathophysiology of atrial fibrillation. Androgen regulates cardiac electrophysiology and calcium (Ca(2+)) homeostasis. The purpose of this study is to evaluate whether androgen receptor knockout (ARKO) can modulate atrial electrophysiology and arrhythmogenesis with modulation of Ca(2+) homeostasis proteins. We used conventional microelectrodes to study the action potential (AP) in left atrium (LA) tissues prepared from wild-type (WT) and ARKO mice (aged 6-10 months) before and after the administration of isoproterenol, hypocalcemic/hypercalcemic solutions, and ouabain. Echocardiography and Western blots were used to evaluate the cardiac function and expression levels of ionic channel proteins in WT and ARKO LAs. ARKO LAs had larger LA diameter with decreased LA fractional shortening than did WT LAs. In the current study, we found that ARKO LAs had a lower negative resting membrane potential and a greater 90% AP duration (APD) than did WT LAs. Isoproterenol increased the incidence and amplitude of delayed afterdepolarizations (DADs) in ARKO LAs but not in WT LAs. Hypocalcemic solutions prolonged APD in WT and ARKO LAs but increased DAD amplitude only in ARKO LAs. Hypercalcemic solutions shortened APD in ARKO LAs but not in WT LAs. Ouabain increased DAD amplitude in ARKO LAs but not in WT LAs. ARKO LAs expressed higher amounts of Ca(2+)/calmodulin-dependent protein kinase II, Na(+)/Ca(2+) exchanger, and phosphorylated phospholamban (Ser-16/Thr-17 site) and less Cav1.2, Kir2.1, Kir3.1, and Kv7.1 than WT LAs. These observations indicate that ARKO alters atrial electrophysiology with increased atrial arrhythmogenesis.

Dehydroepiandrosterone replacement therapy in older adults improves indices of arterial stiffness

Serum dehydroepiandrosterone (DHEA) concentrations decrease approximately 80% between ages 25 and 75 year. Aging also results in an increase in arterial stiffness, which is an independent predictor of cardiovascular disease (CVD) risk and mortality. Therefore, it is conceivable that DHEA replacement in older adults could reduce arterial stiffness. We sought to determine whether DHEA replacement therapy in older adults reduces carotid augmentation index (AI) and carotid-femoral pulse wave velocity (PWV) as indices of arterial stiffness. A randomized, double-blind trial was conducted to study the effects of 50 mg day(-1) DHEA replacement on AI (n = 92) and PWV (n = 51) in women and men aged 65-75 year. Inflammatory cytokines and sex hormones were measured in fasting serum. AI decreased in the DHEA group, but not in the placebo group (difference between groups, -6 ± 2 AI units, P = 0.002). Pulse wave velocity also decreased (difference between groups, -3.5 ± 1.0 m s(-1), P = 0.001); however, after adjusting for baseline values, the between-group comparison became nonsignificant (P = 0.20). The reductions in AI and PWV were accompanied by decreases in inflammatory cytokines (tumor necrosis factor α and IL-6, P < 0.05) and correlated with increases in serum DHEAS (r = -0.31 and -0.37, respectively, P < 0.05). The reductions in AI also correlated with free testosterone index (r = -0.23, P = 0.03). In conclusion, DHEA replacement in elderly men and women improves indices of arterial stiffness. Arterial stiffness increases with age and is an independent risk factor for CVD. Therefore, the improvements observed in this study suggest that DHEA replacement might partly reverse arterial aging and reduce CVD risk.

Effects of dehydroepiandrosterone sulphate (DHEAS) replacement on insulin action and quality of life in hypopituitary females: a double-blind, placebo-controlled study

OBJECTIVE

Addition of dehydroepiandrosterone sulphate (DHEAS) to standard pituitary replacement may improve quality of life and glucose metabolism. Conflicting results from the previous work probably relate to differences in populations studied and assessment techniques used. We examined the effects of DHEAS on insulin action and the quality of life in female patients with hypopituitary hypoadrenalism.

DESIGN

Randomized, double-blind, placebo-controlled, crossover design was used. Patients received either DHEAS 50 mg daily or placebo for 12 weeks.

PATIENTS

Fourteen hypopituitary females on stable standard replacement therapy and with low DHEAS were enrolled.

MEASUREMENTS

Insulin action by euglycaemic hyperinsulinaemic clamp and extensive quality of life parameters were assessed after each treatment.

RESULTS

Serum DHEAS (DHEAS 5·4 ± 0·8 vs placebo <0·8 ± 0·0 μm; P < 0·001) and androstenedione (DHEAS 4·1 ± 0·8 vs placebo 1·3 ± 0·2 nm; P < 0·05) rose to within the normal range after DHEAS 50 mg daily. There were no differences between treatments in testosterone, sex hormone-binding globulin (SHBG) or IGF-1. Quality of life measures were unchanged after DHEAS. There were no differences between treatments in fasting glucose, serum insulin, HbA1c or in insulin action (glucose infusion rates required to maintain euglycaemia; DHEAS 21·9 ± 2·5 vs placebo 24·5 ± 2·1 μmol/kg/min; P = 0·4). Triglyceride concentrations were lower following DHEAS (DHEAS 1·24 ± 0·18 vs placebo 1·41 ± 0·19 mm; P < 0·05) but other lipid parameters remained unchanged.

CONCLUSION

There were no differences compared with placebo in quality of life or insulin action after DHEAS replacement therapy for 12 weeks. These results do not provide evidence for the addition of DHEAS to standard hypopituitary replacement therapy.

Decreased serum adrenal androgen dehydroepiandrosterone sulfate and mortality in hemodialysis patients

BACKGROUND

Endocrine and metabolic abnormalities may affect the survival of hemodialysis patients. Serum dehydroepiandrosterone sulfate (DHEA-S), an adrenal androgen with anabolic properties, is known to be lowered in ill patients and predicts poor outcome in the general population and in those with cardiac disease. The aims of this study were to examine a possible change in the DHEA-S level in dialysis patients and its association with survival in this population.

METHODS

This was an observational cohort study in 494 prevalent hemodialysis patients (313 men and 181 women) in urban area of Osaka, Japan. The main exposure was the baseline DHEA-S level in December 2004 and the key outcome was all-cause mortality during the subsequent 5 years. Also, DHEA-S levels were compared between the hemodialysis patients and 122 matched healthy controls.

RESULTS

The median (inter-quartile range) DHEA-S levels were 771 (447-1351) and 414 (280-659) ng/mL for male and female dialysis patients, respectively, and these values were significantly lower by 40-53% than the healthy control levels. Among the hemodialysis patients, DHEA-S was lower in women, those with older age, pre-existing cardiovascular disease, lower serum albumin and higher C-reactive protein. During the follow-up, we recorded 101 deaths. A low DHEA-S level was a significant predictor of all-cause mortality independent of potential confounders in male, but not in female, hemodialysis patients.

CONCLUSIONS

The serum DHEA-S level is decreased in hemodialysis patients and associated with mortality in men. These results support the growing observational evidence that uremia-induced endocrine alterations including decreased sex hormones may be linked to adverse clinical outcomes.

Pharmacological modulation of arterial stiffness

Arterial stiffness has emerged as an important marker of cardiovascular risk in various populations and reflects the cumulative effect of cardiovascular risk factors on large arteries, which in turn is modulated by genetic background. Arterial stiffness is determined by the composition of the arterial wall and the arrangement of these components, and can be studied in humans non-invasively. Age and distending pressure are two major factors influencing large artery stiffness. Change in arterial stiffness with drugs is an important endpoint in clinical trials, although evidence for arterial stiffness as a therapeutic target still needs to be confirmed. Drugs that independently affect arterial stiffness include antihypertensive drugs, mostly blockers of the renin-angiotensin-aldosterone system, hormone replacement therapy and some antidiabetic drugs such as glitazones. While the quest continues for 'de-stiffening drugs', so far only advanced glycation endproduct cross-link breakers have shown promise.

Dehydroepiandrosterone sulfate and postmenopausal women

PURPOSE OF REVIEW

Levels of dehydroepiandrosterone (DHEA) are known to decline with age. In an era of increasing use of supplements to better life, the benefits of DHEA in the aging female population are controversial. The goal of this article is to critically review published studies to determine if there is a role for DHEA supplementation in postmenopausal women.

RECENT FINDINGS

Daily administration of oral DHEA achieves serum concentrations similar to those of women in their 20s. Several observational studies have shown that lower DHEA levels are associated with increased cardiovascular risk in women; however, interventional trials show no improvement in atherosclerosis or cardiovascular risk factors, and a lowering of HDL cholesterol levels. DHEA supplementation modestly increases bone mineral density in conjunction with adjuvant therapies and improves cognition in those with mild-to-moderate cognitive impairment, but does not affect cognition in unimpaired women. Use of intravaginal DHEA, but not oral DHEA, alleviates vaginal atrophy and improves sexual function in postmenopausal women.

SUMMARY

On the basis of current evidence, there is no role for oral DHEA supplementation in healthy, postmenopausal women. Where benefits have been shown, long-term studies are needed to confirm these benefits and verify the safety profile of DHEA.

Adrenal insufficiency: etiology, diagnosis and treatment

PURPOSE OF REVIEW

Adrenal insufficiency, first codified in 1855 by Thomas Addison, remains relevant in 2010 because of its lethal nature.

RECENT FINDINGS

Reports illuminate features of adrenal insufficiency cause, diagnosis and treatment, and the role of glucocorticoids in critical illness.

SUMMARY

Progress has been made in identifying human leukocyte antigen and major histocompatability complex alleles that predispose to the development of adrenal insufficiency in patients with antibodies to 21-hydroxylase, but their role in clinical care is not established. Reports of HIV-associated infections and medication-induced hypocortisolism are reminders that autoimmune adrenal destruction does not underlie all cases. The diagnosis is adequately established by the 250 microg adrenocortocotropin hormone stimulation test in most patients; the 1 microg test carries the risk of misdiagnosis of healthy individuals as adrenally insufficient. Glucocorticoids provide life-saving treatment, but long-term quality of life is impaired, perhaps because therapy is not given in a physiologic way. The current recommended total daily dose is lower than that often prescribed. Dehydroepiandrosterone replacement may be useful in pubertal girls with hypopituitarism, but not in adults. Supraphysiologic hydrocortisone doses may aid in the reversal of septic shock independent of underlying adrenal function.

Dehydroepiandrosterone (DHEA) treatment in vitro inhibits adipogenesis in human omental but not subcutaneous adipose tissue

Dehydroepiandrosterone (DHEA), a precursor sex steroid, circulates in sulphated form (DHEAS). Serum DHEAS concentrations are inversely correlated with metabolic syndrome components and in vivo/in vitro studies suggest a role in modulating adipose mass. To investigate further, we assessed the in vitro biological effect of DHEA in white (3T3-L1) and brown (PAZ6) preadipocyte cell lines and human primary preadipocytes. DHEA (from 10(-8)M) caused concentration-dependent proliferation inhibition of 3T3-L1 and PAZ6 preadipocytes. Cell cycle analysis demonstrated unaltered apoptosis but indicated blockade at G1/S or G2/M in 3T3-L1 and PAZ6, respectively. Preadipocyte cell-line adipogenesis was not affected. In human primary subcutaneous and omental preadipocytes, DHEA significantly inhibited proliferation from 10(-8)M. DHEA 10(-7)M had opposing effects on adipogenesis in the two fat depots. Subcutaneous preadipocyte differentiation was unaffected or increased whereas omental preadipocytes showed significantly reduced adipogenesis. We conclude that DHEA exerts fat depot-specific differences which modulate body composition by limiting omental fat production.

Metformin reduces arterial stiffness and improves endothelial function in young women with polycystic ovary syndrome: a randomized, placebo-controlled, crossover trial

CONTEXT

Patients with polycystic ovary syndrome (PCOS) have an increased prevalence of insulin resistance and display subclinical evidence of early cardiovascular disease. Metformin improves insulin sensitivity and circulating markers of cardiovascular risk in patients with PCOS, but it is unclear whether this translates into improvements in vascular function.

OBJECTIVE

Our objective was to evaluate the effects of metformin on arterial stiffness and endothelial function in women with PCOS.

DESIGN AND INTERVENTION

Thirty women with PCOS were assigned to consecutive 12-wk treatment periods of metformin or placebo in a randomized, double-blind, crossover design separated by an 8-wk washout.

MAIN OUTCOME MEASURES

The primary outcome measures were assessments of arterial stiffness [augmentation index (AIx), central blood pressure, and brachial and aortic pulse wave velocity (PWV)] and endothelial function. Anthropometry, testosterone, and metabolic biochemistry (lipids, homeostasis model of assessment for insulin resistance, high-sensitivity C-reactive protein, adiponectin, and plasminogen activator inhibitor-1) were also assessed.

RESULTS

Metformin improved AIx [-6.1%; 95% confidence interval (CI) for the difference -8.5 to -3.5%; P < 0.001], aortic PWV (-0.76 m/sec; 95% CI for the difference -1.12 to -0.4 m/sec; P < 0.001), brachial PWV (-0.73 m/sec; 95% CI for the difference -1.09 to -0.38; P < 0.001), central blood pressure (P < 0.001), and endothelium-dependent (AIx after albuterol; P = 0.003) and endothelium-independent (AIx after nitroglycerin; P < 0.001) vascular responses. Metformin also reduced weight (P < 0.001), waist circumference (P < 0.001), and triglycerides (P = 0.004) and increased adiponectin (P = 0.001) but did not affect testosterone or other metabolic measures.

CONCLUSIONS

Short-term metformin therapy improves arterial stiffness and endothelial function in young women with PCOS.