Low testosterone is associated with decreased function and increased mortality risk: a preliminary study of men in a geriatric rehabilitation unit

Testosterone Deficiency as One of the Major Endocrine Disorders in Chronic Kidney Disease

Reduced testosterone concentration is nowadays thought to be one of the main endocrine disorders in chronic kidney disease (CKD). It is caused by the dysfunction of the hypothalamic-pituitary-gonadal axis. The role of testosterone is multifactorial. Testosterone is responsible not only for reproductive processes, but it is a hormone which increases bone and muscle mass, improves lipid profile, insulin sensitivity, erythropoiesis, reduces blood pressure, and ameliorates mood and perception. The implications of hypogonadism in CKD are infertility and loss of libido, reduction of muscle mass and strength, disorders in bone mineralization, the development of sarcopenia and protein energy wasting (PEW), progression of atherosclerosis, increased visceral adiposity, insulin resistance, and anaemia. Reduced testosterone serum concentrations in CKD are associated with increased mortality rate. Testosterone supplementation improves sexual functions, reduces the level of inflammatory markers and blood pressure, stimulates muscle protein synthesis, improves insulin sensitivity and lipid profile, and increases muscle mass, bone mineral density, and haemoglobin concentration. It positively affects mood and well-being. The modes of testosterone supplementation are intramuscular injections, subcutaneous pellets, and percutaneous methods—patches and gels. Successful kidney transplantation may improve gonadal function and testosterone production, however, half of men with low testosterone concentrations before kidney transplantation do not restore hormonal function.

Androgen-Regulated Cardiac Metabolism in Aging Men

The prevalence of cardiovascular mortality is higher in men than in age-matched premenopausal women. Gender differences are linked to circulating sex-related steroid hormone levels and their cardio-specific actions, which are critical factors involved in the prevalence and features of age-associated cardiovascular disease. In women, estrogens have been described as cardioprotective agents, while in men, testosterone is the main sex steroid hormone. The effects of testosterone as a metabolic regulator and cardioprotective agent in aging men are poorly understood. With advancing age, testosterone levels gradually decrease in men, an effect associated with increasing fat mass, decrease in lean body mass, dyslipidemia, insulin resistance and adjustment in energy substrate metabolism. Aging is associated with a decline in metabolism, characterized by modifications in cardiac function, excitation-contraction coupling, and lower efficacy to generate energy. Testosterone deficiency -as found in elderly men- rapidly becomes an epidemic condition, associated with prominent cardiometabolic disorders. Therefore, it is highly probable that senior men showing low testosterone levels will display symptoms of androgen deficiency, presenting an unfavorable metabolic profile and increased cardiovascular risk. Moreover, recent reports establish that testosterone replacement improves cardiomyocyte bioenergetics, increases glucose metabolism and reduces insulin resistance in elderly men. Thus, testosterone-related metabolic signaling and gene expression may constitute relevant therapeutic target for preventing, or treating, age- and gender-related cardiometabolic diseases in men. Here, we will discuss the impact of current evidence showing how cardiac metabolism is regulated by androgen levels in aging men.

Effects of testosterone on circadian rhythmicity in old mice

Serum testosterone concentration decreases with age in humans and rodents. Accordingly, old male mice show changes in locomotor activity rhythms: a lengthened free-running period and decreased activity levels among others. To investigate whether testosterone replacement improves the age-related decline in circadian rhythmicity, we examined the effects of testosterone on the circadian rhythms of wheel running activity in old male mice. Intact male C57BL/6J mice (18-22 months old) were subcutaneously implanted with silicone tubes packed with testosterone propionate (TP) or cholesterol. TP treatment significantly decreased the daily wheel running revolutions in a normal light/dark (LD) cycle and in constant darkness (DD), but did not affect the free-running period. The same experiment performed on young male gonadectomized mice (3-5 months old) demonstrated that TP treatment significantly increased activity levels in both LD and DD. These results suggest that testosterone replacement exacerbates the age-related decline in circadian rhythmicity.

Cortisol, Testosterone, and Prospective Risk for War-zone Stress-Evoked Depression

Introduction

The major challenges of efforts to reveal biological risk factors and biomarkers of depression include the complexity of underlying systems, interactions with other systems, and contextual factors governing their expression. Altered endocrine function is believed to be a central contributor to depressive illness, but across studies, evidence for a link between endocrine markers and depression has been mixed, inconclusive, or conditional in nature. In the present study, we evaluated basal testosterone (T), cortisol (C), and CO2 inhalation-stress-reactivity measures of these hormones (TR, CR) as pre-deployment moderators of the later impact of war-zone stressors on depression symptoms in-theater.

Materials and Methods

At pre-deployment, U.S. soldiers (N = 120) completed demographic, clinical and hormone measures, and during deployment, they completed monthly, web-based assessments of war-zone stressors and depression symptoms (N = 533 observations). Mixed effects models estimated the effects of the pre-deployment hormone profiles in moderating war-zone stressors' impact on in-theater depression. Models also tested whether hormonally linked risk for later stress-evoked depression depends on pre-existing depression.

Results

Controlling for pre-deployment depression, high T was protective; whereas TR had depressogenic effects that were amplified by pre-deployment depression. Further, high C was protective, but heightened CR was depressogenic, but only among those with elevated pre-deployment depression.

Conclusions

Findings highlight the importance of examining basal and reactivity measures of endocrine function, and use of prospective, longitudinal models to test hypothesized causal pathways associated with depression vulnerability in the war-zone. Results also suggest that pre-existing depression and cortisol may work in tandem to increase vulnerability for later stress-evoked depression in the war-zone.

Mechanisms Underlying Metabolic Syndrome-Related Sarcopenia and Possible Therapeutic Measures

Although there are several reviews that report the interrelationship between sarcopenia and obesity and insulin resistance, the relation between sarcopenia and the other signs that compose the metabolic syndrome (MetS) has not been extensively revised. Here, we review the mechanisms underlying MetS-related sarcopenia and discuss the possible therapeutic measures proposed. A vicious cycle between the loss of muscle and the accumulation of intramuscular fat might be associated with MetS via a complex interplay of factors including nutritional intake, physical activity, body fat, oxidative stress, proinflammatory cytokines, insulin resistance, hormonal changes, and mitochondrial dysfunction. The enormous differences in lipid storage capacities between the two genders and elevated amounts of endogenous fat having lipotoxic effects that lead to the loss of muscle mass are discussed. The important repercussions of MetS-related sarcopenia on other illnesses that lead to increased disability, morbidity, and mortality are also addressed. Additional research is needed to better understand the pathophysiology of MetS-related sarcopenia and its consequences. Although there is currently no consensus on the treatment, lifestyle changes including diet and power exercise seem to be the best options.

Testosterone therapy improves well being and psychological health

PURPOSE OF REVIEW

To ascertain whether testosterone therapy (TTh) improves psychological health and a sense of overall well being in a number of clinical domains.

RECENT FINDINGS

Recent work suggests small but durable and replicable improvements in the components of male health and well being.

SUMMARY

Symptomatic hypogonadism is frequently associated with decreased libido and fatigue that contributes to lowered overall quality-of-life and worsening psychological health. This manuscript will review the evidence behind the generalized benefits of TTh on overall male health as well as on depression and cognitive function in particular. Influence of TTh on body composition and its relationship to cardiovascular disease are also discussed in this overall context.

Testosterone Replacement, Muscle Strength, and Physical Function

Muscle strength and physical function decrease in older men, as do testosterone levels. Nonetheless, the effects of testosterone replacement therapy on muscle strength and physical function remain inconclusive and equivocal. We conducted a rapid systematic review, the results of which showed that testosterone replacement does not affect muscle strength (measured by hand grip strength and leg muscle strength), although it may increase physical function (measured by the 6-minute walk test, Physical Activity Scale for the Elderly score, and other physical performance tests). However, most of the studies were conducted in the United States or Europe and did not include participants from Asian or other ethnic backgrounds; therefore, further studies are needed to evaluate the effects of testosterone replacement in a broader population.

Testosterone and androstanediol glucuronide among men in NHANES III

Background

Most of the androgen replacement therapies were based on serum testosterone and without measurements of total androgen activities. Whether those with low testosterone also have low levels of androgen activity is largely unknown. We hence examined the association between testosterone and androstanediol glucuronide (AG), a reliable measure of androgen activity, in a nationally representative sample of US men.

Methods

Cross-sectional analysis was based on 1493 men from the Third National Health and Nutrition examination Survey (NHANES III) conducted from 1988 to 1991. Serum testosterone and AG were measured by immunoassay. Kernel density was used to estimate the average density of serum AG concentrations by quartiles of testosterone.

Results

Testosterone was weakly and positively correlated with AG (correlation coefficient = 0.18). The kernel density estimates show that the distributions are quite similar between the quartiles of testosterone. After adjustment for age, the distributions of AG in quartiles of testosterone did not change. The correlation between testosterone and AG was stronger in men with younger age, lower body mass index, non-smoking and good self-rated health and health status.

Conclusions

Serum testosterone is weakly correlated with total androgen activities, and the correlation is even weaker for those with poor self-rated health. Our results suggest that measurement of total androgen activity in addition to testosterone is necessary in clinical practice, especially before administration of androgen replacement therapy.

The Anxiolytic and Antidepressant-like Effects of Testosterone and Estrogen in Gonadectomized Male Rats

BACKGROUND

While the influence of testosterone levels on vulnerability to affective disorders is not straightforward, research suggests this hormone may confer some degree of resiliency in men. We recently demonstrated a role for the dentate gyrus in mediating testosterone's protective effects on depressive-like behavior in gonadectomized male rats. Here, testosterone may exert its effects through androgen receptor-mediated mechanisms or via local aromatization to estradiol.

METHODS

Gonadectomized male rats were implanted with a placebo, testosterone, or estradiol pellet, and subsequent protective anxiolytic- and antidepressant-like effects of testosterone and its aromatized metabolite, estradiol, were then investigated in the open field and sucrose preference tests, respectively. Moreover, their influence on gene expression in the hippocampus was analyzed by genome-wide complementary DNA microarray analysis. Finally, the contribution of testosterone's aromatization within the dentate gyrus was assessed by local infusion of the aromatase inhibitor fadrozole, whose efficacy was confirmed by liquid chromatography-tandem mass spectrometry.

RESULTS

Both hormones had antidepressant-like effects associated with a substantial overlap in transcriptional regulation, particularly in synaptic plasticity- and mitogen-activated protein kinase pathway-related genes. Further, chronic aromatase inhibition within the dentate gyrus blocked the protective effects of testosterone.

CONCLUSIONS

Both testosterone and estradiol exhibit anxiolytic- and antidepressant-like effects in gonadectomized male rats, while similarly regulating critical mediators of these behaviors, suggesting common underlying mechanisms. Accordingly, we demonstrated that testosterone's protective effects are mediated, in part, by its aromatization in the dentate gyrus. These findings thus provide further insight into a role for estradiol in mediating the protective anxiolytic- and antidepressant-like effects of testosterone.

Testosterone treatment of men with mild cognitive impairment and low testosterone levels

INTRODUCTION

This study investigated the effects of testosterone (T) treatment on cognition, mood, and quality of life in men with mild cognitive impairment (MCI) and low serum T levels.

METHODS

A total of 351 community-dwelling men were screened, and 37 men evidenced both MCI and low T of whom 27 agreed for further screening. Twenty-two met all the study inclusion/exclusion criteria and enrolled in a 6-month randomized, double-blind, placebo-controlled study.

RESULTS

Total T levels significantly increased in the T treatment group. No significant changes were observed in measures of cognition, mood, or quality of life other than improvement in 1 objective measure of verbal memory (P < .05) and decreased depression symptoms (P < .02) in the treatment group.

CONCLUSIONS

Testosterone treatment may modestly improve verbal memory and depression symptoms in men with both MCI and low T.

Beneficial effects of 2 years of administration of parenteral testosterone undecanoate on the metabolic syndrome and on non-alcoholic liver steatosis and C-reactive protein

BACKGROUND

Elderly men often show a concurrence of a decline of testosterone with attributes of the metabolic syndrome. This study tested the effects of normalization of testosterone.

MATERIALS AND METHODS

A total of 122 hypogonadal men (18-83 years, mean 59.6±8.0 years; n=11<45 years, n=25<55 years, n=53<65 years) were included in the study. Their baseline testosterone levels were between 0.14 and 4.51 ng/mL (n>4.90 ng/mL) and were treated with parenteral testosterone undecanoate for 2 years as the sole intervention (administration at 0 and 6 weeks, and thereafter every 12 weeks).

RESULTS

Plasma testosterone increased from 3.3±1.9 ng/mL to 4.1±1.5 ng/mL (p<0.01) at 3 months, and then stabilized at 6.8±1.3 ng/mL after the first 6 months. There was a remarkable progressive linear decline in body weight, body mass index, and waist circumference over the entire study period. Plasma cholesterol decreased significantly over the first 12 months, and then stabilized. Plasma glucose, triglycerides, low-density lipoprotein cholesterol, and C-reactive protein decreased significantly and high-density lipoprotein cholesterol increased significantly over the 24-month study period in a non-linear manner. There was a significant decrease in aspartate aminotransferase and alanine aminotransferase levels over the first 9 and 12 months, and then values leveled off. Changes in variables were largely correlated with changes in testosterone levels. At baseline, 47 out of 122 subjects fulfilled the metabolic syndrome criteria as defined by the National Cholesterol Education Program (2001); after 2 years of testosterone treatment, this number had declined to 11 out of 122 subjects.

CONCLUSION

With testosterone treatment over 2 years, the most significant improvement of the metabolic syndrome was noted over the first 12 months, but over the following 12 months further improvement was also observed. With regard to safety of testosterone administration to mainly elderly men, a number of safety measures were carried out.

Age, obesity and inflammation at baseline predict the effects of testosterone administration on the metabolic syndrome

BACKGROUND

Testosterone administration to hypogonadal men improves the metabolic syndrome. This study analyzed whether age, serum testosterone, body mass index/waist circumference, increment in testosterone values and C-reactive protein (CRP) predicted the outcome of testosterone administration.

MATERIALS AND METHODS

A total of 110 mainly elderly men, aged between 18 and 83 years (mean±SD=59.6±8.0) with baseline serum testosterone of 5.8-12.1 nmol/L (mean±SD=9.3±1.7) (n>14.0 nmol/L), received parenteral testosterone undecanoate whereupon serum testosterone normalized between 3 and 24 months.

RESULTS

(i) The lower the baseline testosterone, the stronger the decreases in waist size and triglycerides. (ii) The greater the increment in serum testosterone, the stronger the decreases in low-density lipoprotein (LDL) cholesterol, triglycerides and glucose. (iii) Older age was associated with stronger beneficial effects on waist size, glucose and all lipids, but a small negative effect on high-density lipoprotein cholesterol. (iv) Obese men and men with the largest waist circumference showed the strongest declines over 2 years in weight, waist circumference and body mass index (BMI), and also in total cholesterol, triglycerides and glucose. Baseline BMI predicted a stronger decline in LDL cholesterol, but a smaller decline in CRP levels. (v) Higher baseline CRP predicted larger declines in levels of triglycerides, glucose and CRP. (vi) In the multivariate model, age, BMI and CRP were independent predictors of the strongest benefit of testosterone treatment on the metabolic syndrome.

CONCLUSIONS

Older men, particularly when obese with chronic low-grade inflammation benefited most of normalizing their testosterone levels, preferably if they reached mid-normal reference values.

Testosterone, aging and survival: biomarker or deficiency

PURPOSE OF REVIEW

The purpose of this study is to review recent studies that examined the association of endogenous and exogenous testosterone and mortality in older men.

RECENT FINDINGS

Over the past several years, there has been a steep rise in testosterone prescriptions. The increased use of testosterone occurred in the context of several studies that reported an association between low serum testosterone and increased cardiovascular events and mortality. In contrast, recent studies have reported an association between testosterone treatment and adverse events. A testosterone treatment trial of mobility-impaired elderly men with prevalent cardiovascular disease was stopped due to increased cardiovascular events in the T-treated men and a meta-analysis reported increased cardiovascular events in T-treated men. In two recent large observational studies, testosterone treatment was associated with an increased risk for serious adverse cardiovascular events.

SUMMARY

Low testosterone is associated with mortality in multiple cohort studies; however, it is unclear if this is a causal association or due to low testosterone being a biomarker of poor health. Given recent reports of adverse outcomes associated with testosterone treatment, a conservative use of testosterone is warranted in men with cardiovascular disease who may be at greater risk for adverse outcomes.

Prevalence of low testosterone levels in men with type 2 diabetes mellitus: a cross-sectional study

Background:

A high prevalence of low serum testosterone (LST) in men with type 2 diabetes have been reported worldwide. The aim of this study was to determine the prevalence and associated factors of LST in men with type 2 diabetes.

Materials and Methods:

This was a cross-sectional study, conducted among 1,089 men (aged 30-70 years) with type 2 diabetes who consecutively attended a major diabetes center in Amman, Jordan, between August 2008 and February 2009. The patients’ demographic characteristics were collected using a prestructured questionnaire. Duration of diabetes, smoking habits, presence of retinopathy, neuropathy, and nephropathy were collected from the medical records. All participants were asked to complete the Androgen Deficiency in Ageing Male (ADAM) questionnaire. Venous blood sample was collected to test for total testosterone (TT), free testosterone (FT), sex hormone binding globulin (SHBG), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), serum lipids, and glycosylated hemoglobin (HbA1c). LST was defined as TT <3 ng/ml.

Results:

Overall, 36.5% of patients with diabetes had TT level <3 ng/ml and 29% had symptoms of androgen deficiency. Of those with serum testosterone level <3 ng/ml, 80.2% had symptoms of androgen deficiency, 16.9% had primary hypogonadism (HG), and 83.1% had secondary HG. Univariate analysis showed a significant relationship between age, income, education, body mass index (BMI), smoking, duration of diabetes, diabetic nephropathy, diabetic neuropathy, and HbA1c. Multivariate logistic regression analysis indicated age, income, BMI, and diabetic neuropathy as the independent risk factors of LST.

Conclusions:

The prevalence of LST among men with type 2 diabetes is high. Age, income, BMI, and diabetic neuropathy were found to be the independent risk factors for LST.

Gender differences in serum testosterone and cortisol in patients with major depressive disorder compared with controls

OBJECTIVE

Testosterone may have a role distinct from cortisol in the pathophysiology of depression. The hypothalamus-pituitary-adrenal (HPA) axis affects the functions of sex steroid hormones through interaction with corticotropin-releasing hormone (CRH) and gonadotropin-releasing hormone (GnRH). The objective of this study was to investigate differences in serum levels of testosterone and cortisol in male and female patients with major depressive disorder (MDD).

METHODS

Participants included 87 inpatients with MDD at Juntendo University Koshigaya Hospital. Serum levels of testosterone and cortisol were assessed at admission. Matched controls included 128 healthy individuals. Data from MDD patients and controls were compared separately for men and women. Correlations between serum hormone levels and scores on the Hamilton Rating Scale for Depression (HAM-D) of patients were assessed by sex. Effects of various factors on testosterone and cortisol were analyzed using multiple regression analysis.

RESULTS

In male patients with MDD, a significant negative correlation was seen between testosterone levels and the "retardation" score of HAM-D. However, serum testosterone levels were not significantly different in either male or female MDD patients compared with controls. Serum testosterone was negatively associated with the number of depressive episodes in male patients with MDD. Serum cortisol levels in female patients were significantly increased compared with female controls with no significant correlations between cortisol levels and HAM-D scores.

CONCLUSIONS

The negative correlation between the sub-score of the HAM-D and testosterone may be associated with the biological pathophysiology of male depression. Findings of serum cortisol levels in women may suggest distinct characteristics of these hormones in men and women with MDD.

Testosterone and insulin resistance in the metabolic syndrome and T2DM in men

Obesity, type 2 diabetes mellitus and the metabolic syndrome are major risk factors for cardiovascular disease. Studies have demonstrated an association between low levels of testosterone and the above insulin-resistant states, with a prevalence of hypogonadism of up to 50% in men with type 2 diabetes mellitus. Low levels of testosterone are also associated with an increased risk of all-cause and cardiovascular mortality. Hypogonadism and obesity share a bidirectional relationship as a result of the complex interplay between adipocytokines, proinflammatory cytokines and hypothalamic hormones that control the pituitary-testicular axis. Interventional studies have shown beneficial effects of testosterone on components of the metabolic syndrome, type 2 diabetes mellitus and other cardiovascular risk factors, including insulin resistance and high levels of cholesterol. Biochemical evidence indicates that testosterone is involved in promoting glucose utilization by stimulating glucose uptake, glycolysis and mitochondrial oxidative phosphorylation. Testosterone is also involved in lipid homeostasis in major insulin-responsive target tissues, such as liver, adipose tissue and skeletal muscle.

Effects of short-term testosterone administration on variables of the metabolic syndrome, in particular aldosterone

Abstract Background: The ATPIII criteria of the metabolic syndrome (MS) comprise impaired fasting glucose (>5.6 nmol/L), waist circumference >102 cm, hypertension (>130/85 mm Hg), high triglycerides (>1.7 nmol/L) and low HDL cholesterol (≤1.03 nmol/L). Aldosterone is currently recognized as a key factor in the pathogenesis of cardiovascular diseases and insulin resistance, linking hypertension to MS and obesity. Further, the MS is related to psychological functioning.

MATERIALS AND METHODS

Forty-two men older than 40 years with BMI >30 kg/m2, chronic heart failure (CHF) and serum testosterone (T) <12.0 nmol/L were recruited. Of these 42, 26 consented to T treatment and received two injections with T undecanoate 1000 mg. Biochemical variables relevant for the MS and also serum aldosterone were determined before and after injections; an echocardiography and Aging Males' Symptoms (AMS) scale were also utilized.

RESULTS AND CONCLUSIONS

After 24 weeks of testosterone administration, there were significant declines of insulin and homeostatic model assessment and of serum aldosterone, but no changes in blood pressure. Serum glucose declined but not significantly (p=0.073). There was a slight increase in LDL cholesterol and a decrease in triglycerides. Other variables of MS and other biochemical variables did not change. Echocardiographical variables did not change. The AMS showed improvements over the first 3 months after testosterone administration but, although sustained, there was no further improvement. Short-term testosterone administration over 24 weeks led to some improvements of variables of the MS, notably of aldosterone. Longer-term studies are needed to analyze whether the decrease in serum aldosterone will improve blood pressure and glycemic control.

Testosterone and cardiovascular disease in men

Despite regional variations in the prevalence of coronary artery disease (CAD), men are consistently more at risk of developing and dying from CAD than women, and the gender-specific effects of sex hormones are implicated in this inequality. This 'Perspectives' article reviews the current evidence regarding the cardiovascular effects of testosterone in men including an examination of the age-related decline in testosterone, the relationship between testosterone levels and coronary disease, coronary risk factors and mortality. We also review the vaso-active effects of testosterone, and discuss how these have been used in men with heart failure and angina. We discuss the 'cause' versus 'effect' controversy, regarding low testosterone levels in men with coronary heart disease, as well as concerns over the use of testosterone replacement therapy in middle aged and elderly men. The article concludes with a discussion regarding the future direction for work in this interesting area, including the relative merits of screening for, and treating hypogonadism with testosterone replacement therapy in men with heart disease.

The role of androgens and estrogens on healthy aging and longevity

Aging is associated with a loss of sex hormone in both men (andropause) and women (menopause). In men, reductions in testosterone can trigger declines in muscle mass, bone mass, and in physical function. In women, the impact of the loss of sex hormones, such as estradiol, on bone is well elucidated, but evidence is limited on whether the loss of estradiol negatively affects muscle mass and physical function. However, deficiencies in multiple anabolic hormones have been shown to predict health status and longevity in older persons. Thus, consideration should be given as to whether targeted hormone replacement therapies may prove effective at treating clinical conditions, such as age-related sarcopenia, cancer cachexia, and/or acute or chronic illnesses. If initiated carefully in the appropriate clinical population, hormone replacement therapies in men and women may prevent and reverse muscle and bone loss and functional declines and perhaps promote healthy aging and longevity.

Sex hormones and cause-specific mortality in the male veterans: the Vietnam Experience Study

BACKGROUND

Testosterone levels have been linked to life expectancy in men, less is known about the sex hormones follicular stimulating hormone and luteinizing hormone.

AIM

To examine the association of testosterone, follicular stimulating hormone, luteinizing hormone with mortality.

DESIGN

Prospective cohort analysis.

METHODS

Participants were 4255 Vietnam-era US army veterans with a mean age of 38.3 years. From military service files, telephone interviews and a medical examination, socio-demographic and health data were collected. Contemporary morning fasted hormone concentrations were determined. All-cause, cardiovascular, cancer, external and 'other' cause mortality was ascertained over the subsequent 15 years. Hazard ratios were calculated, first with adjustment for age and then, additionally, for a range of confounders.

RESULTS

Individuals within the highest tertiles of follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels were at increased risk of all-cause mortality following adjustment for a range of risk factors. However, with mutual adjustment, neither FSH nor LH significantly predicted mortality. Testosterone levels did not show an association with all-cause mortality, and none of the hormones were significantly associated with CVD, cancer, 'other' or external-cause mortality in fully adjusted models.

CONCLUSION

Greater FSH and LH levels are associated with all-cause mortality, but not independently of one another.

Clinical review: Endogenous testosterone and mortality in men: a systematic review and meta-analysis

CONTEXT

Low testosterone levels have been associated with outcomes that reduce survival in men.

OBJECTIVE

Our objective was to perform a systematic review and meta-analysis of published studies to evaluate the association between endogenous testosterone and mortality.

DATA SOURCES

Data sources included MEDLINE (1966 to December 2010), EMBASE (1988 to December 2010), and reference lists.

STUDY SELECTION

Eligible studies were published English-language observational studies of men that reported the association between endogenous testosterone and all-cause or cardiovascular disease (CVD) mortality. A two-stage process was used for study selection. 1) Working independently and in duplicate, reviewers screened a subset (10%) of abstracts. Results indicated 96% agreement, and thereafter, abstract screening was conducted in singlicate. 2) All full-text publications were reviewed independently and in duplicate for eligibility.

DATA EXTRACTION

Reviewers working independently and in duplicate determined methodological quality of studies and extracted descriptive, quality, and outcome data.

DATA SYNTHESIS

Of 820 studies identified, 21 were included in the systematic review, and 12 were eligible for meta-analysis [n = 11 studies of all-cause mortality (16,184 subjects); n = 7 studies of CVD mortality (11,831 subjects)]. Subject mean age and testosterone level were 61 yr and 487 ng/dl, respectively, and mean follow-up time was 9.7 yr. Between-study heterogeneity was observed among studies of all-cause (P < .001) and CVD mortality (P = 0.06), limiting the ability to provide valid summary estimates. Heterogeneity in all-cause mortality (higher relative risks) was observed in studies that included older subjects (P = 0.020), reported lower testosterone levels (P = 0.018), followed subjects for a shorter time period (P = 0.010), and sampled blood throughout the day (P = 0.030).

CONCLUSION

Low endogenous testosterone levels are associated with increased risk of all-cause and CVD death in community-based studies of men, but considerable between-study heterogeneity, which was related to study and subject characteristics, suggests that effects are driven by differences between cohorts (e.g. in underlying health status).

Testosterone is not associated with mortality in older African-American males

INTRODUCTION. Although testosterone and its association with disease progression and mortality is a widely studied topic, no studies have evaluated mortality risks related to testosterone levels in an older African-American population. The mechanisms for known racial differences in mortality risk for certain cancers and cardiovascular risk factors are largely unknown. Elucidating a mortality risk associated with testosterone levels may give insight into the elevated risk for certain diseases in African-Americans. METHODS AND RESULTS. Study data were derived from a cohort 622 African-Americans (age 80.05  ±  6.4, range 68-102) from Saint Louis, Missouri that includes 190 males (age 79.38  ±  6.2, range 70-102). The eligible sample for this report includes 56 of the 190 males (age 78.89  ±  6.9, range 70-102) who donated blood at baseline in 1992-1994 and subsequently tested for total testosterone and bioavailable testosterone. Covariates for adjusted analyses were lower body functional limitations, physician visits and comorbidities, also collected at baseline. Males' mean bioavailable testosterone levels (ng/dl) were 33.33  ±  24.4 (n above 70 ng/dl = 5) and mean total testosterone levels (ng/dl) were 246.63  ±  118.7 (n above 300 ng/dl = 20). Vital status was determined through 2002; 41 males (73%) were deceased and 15 were alive. Mortality did not differ among males with testosterone levels <300 versus 300+ (p = 0.42) or with bioavailable testosterone levels <70 versus > 70 (p  =  0.34). Total testosterone levels did not predict mortality when adjusted for age (Adjusted Hazard Ratio [AHR] = 0.998; 95% confidence interval [CI] 0.995-1.001; p = 0.28) or adjusted for age and other covariates (AHR  =  0.099; 95% CI 0.996, 1.002; p  =  0.35). Bioavailable testosterone levels did not predict mortality when adjusted for age (AHR  =  0.992; 95% CI .977-1.007; p  =  0.30) or when adjusted for age and other covariates (AHR 0.991; 95% CI .976-1.006; p  =  0.261). CONCLUSION. In older African-American males, total and bioavailable testosterone levels, with and without adjustment for covariates, are not independently associated with mortality risk.

Endocrinology of the aging male

The endocrinology of the aging male is complex, with multiple hormones along the hypothalamic-pituitary-testicular (HPT) axis interacting with one another in feedback. As men age, there is a small and progressive (not precipitous, as in women) decline in several sex hormones, in particular testosterone and dehydroepiandrosterone, and related increases in luteinizing hormone, follicle-stimulating hormone, and sex hormone-binding globulin. The importance of these changes is wide-ranging because of the ubiquitous role of sex hormones in male physiology. This chapter discusses the endocrinology of the aging male. We provide an overview of the regulation of the HPT axis with an emphasis on the changes that occur with aging and the measurement of gonadal steroids, including hormone pulsatility, within-subject and circadian variations. The difficulties of assessing the symptoms of late-onset hypogonadism are highlighted. There is a comprehensive discussion of the epidemiology of sex hormone changes, including their age associations, prevalence of symptomatic hypogonadism, secular changes, risk factors, and the association of sex hormones with outcomes.

The role of testosterone in the etiology and treatment of obesity, the metabolic syndrome, and diabetes mellitus type 2

Obesity has become a major health problem. Testosterone plays a significant role in obesity, glucose homeostasis, and lipid metabolism. The metabolic syndrome is a clustering of risk factors predisposing to diabetes mellitus type 2, atherosclerosis, and cardiovascular morbidity and mortality. The main components of the syndrome are visceral obesity, insulin resistance, glucose intolerance, raised blood pressure and dyslipidemia (elevated triglycerides, low levels of high-density lipoprotein cholesterol), and a proinflammatory and thrombogenic state. Cross-sectional epidemiological studies have reported a direct correlation between plasma testosterone and insulin sensitivity, and low testosterone levels are associated with an increased risk of type 2 diabetes mellitus, dramatically illustrated by androgen deprivation in men with prostate carcinoma. Lower total testosterone and sex hormone-binding globulin (SHBG) predict a higher incidence of the metabolic syndrome. Administration of testosterone to hypogonadal men reverses part of the unfavorable risk profile for the development of diabetes and atherosclerosis.

Effects of testosterone supplementation on markers of the metabolic syndrome and inflammation in hypogonadal men with the metabolic syndrome: the double-blinded placebo-controlled Moscow study

OBJECTIVE

Men with the metabolic syndrome (MetS) have low plasma testosterone (T) levels. The aim of this study was to establish whether the normalization of plasma T improves the features of the MetS.

DESIGN

A randomized, placebo-controlled, double-blinded, phase III trial of 184 men suffering from both the MetS and hypogonadism.

PATIENTS

One hundred and eighty-four men, aged 35-70, with the MetS and hypogonadism (baseline total T level <12·0 nm or calculated free T level <225 pm.), recruited in the outpatient andrology and urology clinic, Research Center for Endocrinology in Moscow, Russia.

INTERVENTION

Treatment for 30 weeks with either parenteral T undecanoate (n = 113; TU; 1000 mg IM) or placebo (n = 71), administered at baseline, and after 6 and 18 weeks. One hundred and five (92·9%) men receiving TU and 65 (91·5%) receiving placebo completed the trial.

MEASUREMENTS

Body weight, body mass index (BMI), waist circumference (WC), hip circumference, waist-to-hip ratio, insulin, leptin, glucose, cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, C-reactive protein (CRP), interleukin-1-beta (IL-1β), interleukin-6 (IL-6), interleukin-10 (IL-10) and tumour necrosis factor-alpha (TNF-α).

RESULTS

There were significant decreases in weight, BMI and WC in the TU vs placebo group. Levels of leptin and insulin also decreased, but there were no changes in serum glucose or lipid profile. Of the inflammatory markers, IL-1β, TNF-α and CRP decreased, while IL-6 and IL-10 did not change significantly.

CONCLUSIONS

Thirty weeks of T administration normalizing plasma T in hypogonadal men with the MetS improved some components of the MetS and a number of inflammatory markers.

Endogenous testosterone and mortality in male hemodialysis patients: is it the result of aging?

BACKGROUND AND OBJECTIVES

Low serum testosterone levels in hemodialysis (HD) patients have recently been associated with cardiovascular risk factors and increased mortality. To confirm this observation, we investigated the predictive role of serum total testosterone levels on mortality in a large group of male HD patients from Turkey.

DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS

A total of 420 prevalent male HD patients were sampled in March 2005 and followed up for all-cause mortality. Serum total testosterone levels were measured by ELISA at baseline and studied in relation to mortality and cardiovascular risk profile.

RESULTS

Mean testosterone level was 8.69 ± 4.10 (0.17 to 27.40) nmol/L. A large proportion of patients (66%) had testosterone deficiency (<10 nmol/L). In univariate analysis, serum testosterone levels were positively correlated with creatinine and inversely correlated with age, body mass index, and lipid parameters. During an average follow-up of 32 months, 104 (24.8%) patients died. The overall survival rate was significantly lower in patients within the low testosterone tertile (<6.8 nmol/L) compared with those within the high tertile (>10.1 nmol/L; 64 versus 81%; P = 0.004). A 1-nmol/L increase in serum testosterone level was associated with a 7% decrease in overall mortality (hazard ratio 0.93; 95% confidence interval 0.89 to 0.98; P = 0.01); however, this association was dependent on age and other risk factors in adjusted Cox regression analyses.

CONCLUSIONS

Testosterone deficiency is common in male HD patients. Although testosterone levels, per se, predicted mortality in this population, this association was largely dependent on age.

The role of testosterone in type 2 diabetes and metabolic syndrome in men

Over the last three decades, it has become apparent that testosterone plays a significant role in glucose homeostasis and lipid metabolism. The metabolic syndrome is a clustering of risk factors predisposing to diabetes mellitus type 2, atherosclerosis and cardiovascular morbidity and mortality. The main components of the syndrome are visceral obesity, insulin resistance, glucose intolerance, raised blood pressure and dyslipidemia (elevated triglycerides, low levels of high-density lipoprotein cholesterol), and a pro-inflammatory and thrombogenic state. Cross-sectional epidemiological studies have reported a direct correlation between plasma testosterone and insulin sensitivity, and low testosterone levels are associated with an increased risk of type 2 diabetes mellitus, dramatically illustrated by androgen deprivation in men with prostate carcinoma. Lower total testosterone and sex hormone-binding globulin (SHBG) predict a higher incidence of the metabolic syndrome. There is evidence that hypotestosteronemia should be an element in the definition of the metabolic syndrome since low levels of testosterone are associated with or predict the development of the metabolic syndrome and of diabetes mellitus. Administration of testosterone to hypogonadal men reverses part of the unfavorable risk profile for the development of diabetes and atherosclerosis. So far, studies on the effects of normalization of testosterone in hypogonadal men on glucose homeostasis are limited, but convincing, and if diabetes mellitus is viewed in the context of the metabolic syndrome, the present results of testosterone treatment are very encouraging.

Androgens, angiogenesis and cardiovascular regeneration

PURPOSE OF REVIEW

Striking sex differences exist not only in the incidence of cardiovascular disease, but also in the clinical outcomes. Although cardiovascular events occur earlier in men, in women, it appears they have poorer short-term and long-term outcomes following these events compared to men. Thus, intrinsic sex differences may exist not only in atherogenesis, but also with respect to cardiovascular adaptation/repair in response to ischemia and/or infarction. Angiogenesis, the growth of new blood vessels, is essential for organ development and is critical to cardiovascular repair/regeneration. Although the effect of estrogen on angiogenesis has been studied extensively, the role of androgens has remained largely unexplored.

RECENT FINDINGS

Multiple lines of evidence now suggest an important role for androgens in cardiovascular repair and regeneration. Studies suggest that androgens stimulate angiogenesis via vascular endothelial growth factor-related mechanisms and by the stimulation of erythropoietin production. Furthermore, endothelial progenitor cells, important in angiogenesis, appear to be hormonally regulated and an important target of androgen action.

SUMMARY

Given the age-related decline in androgens, the findings discussed here have implications for therapeutic angiogenesis and androgen replacement therapies in aging and hypogonadal men.

Androgens and male aging: Current evidence of safety and efficacy

Many signs of aging, such as sexual dysfunction, visceral obesity, impaired bone and muscle strength, bear a close resemblance to features of hypogonadism in younger men. The statistical decline of serum testosterone in aging men is solidly documented. It has been presumed that the above features of aging are related to the concurrent decline of androgens, and that correction of the lower-than-normal circulating levels of testosterone will lead to improvement of symptoms of aging. But in essence, the pivotal question whether the age-related decline of testosterone must be viewed as hypogonadism, in the best case reversed by testosterone treatment, has not been definitively resolved. Studies in elderly men with lower-than-normal testosterone report improvement of features of the metabolic syndrome, bone mineral density, of mood and of sexual functioning. But as yet there is no definitive proof of the beneficial effects of restoring testosterone levels to normal in elderly men on clinical parameters. Few of these studies meet as yet rigorous standards of scientific enquiry: double-blind, placebo-controlled design of the study. The above applies also to the assessment of safety of testosterone administration to elderly men. There is so far no convincing evidence that testosterone is a main factor in the development of prostate cancer in elderly men and guidelines for monitoring the development of prostate disease have been developed. It is of note that there are presently no long-term safety data with regard to the prostate. Polycythemia is another potential complication of testosterone treatment. It is dose dependent and can be managed with dose adjustment.

The relationship between testosterone deficiency and frailty in elderly men

The vulnerable health status usually preceding the onset of overt disability is often referred to as frailty. A stringent definition is elusive but it can be viewed as a physiological syndrome, characterized by decreased reserve and diminished resistance to stressors, resulting from a cumulative decline across multiple physiological systems and causing vulnerability to adverse outcomes. Elements of frailty are related to the neurological system, metabolism, joints, bones, and muscles. Sarcopenia seems to be the major determinant of frailty. Several components of the frailty syndrome are related to loss of physiological actions of testosterone (T). T and/or its aromatized metabolite, estradiol, are necessary for maintenance of bone mineral density. Furthermore, T stimulates erythrocyte formation. T has a profound effect on body composition. Androgens promote differentiation of mesenchymal pluripotent cells into the myogenic lineage and inhibit differentiation into the adipogenic lineage. Skeletal muscles of older men are as responsive to the anabolic effects of T as of younger men. Thus, although frailty is obviously a complex syndrome, some elements are androgen-associated and these can improve in men with subnormal T levels when treated with T. Evidence suggests that T treatment in frail elderly men with low T improves body composition, quality of life, and physical function, including increased axial bone mineral density and body composition. The data available to date strongly suggest a relationship between T-deficiency and frailty and warrant further basic and clinical investigations to extend these observations to the management of elderly men with frailty.

Position stand on androgen and human growth hormone use

Hoffman, JR, Kraemer, WJ, Bhasin, S, Storer, T, Ratamess, NA, Haff, GG, Willoughby, DS, and Rogol, AD. Position stand on Androgen and human growth hormone use. J Strength Cond Res 23(5): S1-S59, 2009-Perceived yet often misunderstood demands of a sport, overt benefits of anabolic drugs, and the inability to be offered any effective alternatives has fueled anabolic drug abuse despite any consequences. Motivational interactions with many situational demands including the desire for improved body image, sport performance, physical function, and body size influence and fuel such negative decisions. Positive countermeasures to deter the abuse of anabolic drugs are complex and yet unclear. Furthermore, anabolic drugs work and the optimized training and nutritional programs needed to cut into the magnitude of improvement mediated by drug abuse require more work, dedication, and preparation on the part of both athletes and coaches alike. Few shortcuts are available to the athlete who desires to train naturally. Historically, the NSCA has placed an emphasis on education to help athletes, coaches, and strength and conditioning professionals become more knowledgeable, highly skilled, and technically trained in their approach to exercise program design and implementation. Optimizing nutritional strategies are a vital interface to help cope with exercise and sport demands (). In addition, research-based supplements will also have to be acknowledged as a strategic set of tools (e.g., protein supplements before and after resistance exercise workout) that can be used in conjunction with optimized nutrition to allow more effective adaptation and recovery from exercise. Resistance exercise is the most effective anabolic form of exercise, and over the past 20 years, the research base for resistance exercise has just started to develop to a significant volume of work to help in the decision-making process in program design (). The interface with nutritional strategies has been less studied, yet may yield even greater benefits to the individual athlete in their attempt to train naturally. Nevertheless, these are the 2 domains that require the most attention when trying to optimize the physical adaptations to exercise training without drug use.Recent surveys indicate that the prevalence of androgen use among adolescents has decreased over the past 10-15 years (). The decrease in androgen use among these students may be attributed to several factors related to education and viable alternatives (i.e., sport supplements) to substitute for illegal drug use. Although success has been achieved in using peer pressure to educate high school athletes on behaviors designed to reduce the intent to use androgens (), it has not had the far-reaching effect desired. It would appear that using the people who have the greatest influence on adolescents (coaches and teachers) be the primary focus of the educational program. It becomes imperative that coaches provide realistic training goals for their athletes and understand the difference between normal physiological adaptation to training or that is pharmaceutically enhanced. Only through a stringent coaching certification program will academic institutions be ensured that coaches that they hire will have the minimal knowledge to provide support to their athletes in helping them make the correct choices regarding sport supplements and performance-enhancing drugs.The NSCA rejects the use of androgens and hGH or any performance-enhancing drugs on the basis of ethics, the ideals of fair play in competition, and concerns for the athlete's health. The NSCA has based this position stand on a critical analysis of the scientific literature evaluating the effects of androgens and human growth hormone on human physiology and performance. The use of anabolic drugs to enhance athletic performance has become a major concern for professional sport organizations, sport governing bodies, and the federal government. It is the belief of the NSCA that through education and research we can mitigate the abuse of androgens and hGH by athletes. Due to the diversity of testosterone-related drugs and molecules, the term androgens is believed to be a more appropriate term for anabolic steroids.

Low serum testosterone and estradiol predict mortality in elderly men

CONTEXT

Age-related reduction of serum testosterone may contribute to the signs and symptoms of aging, but previous studies report conflicting evidence about testosterone levels and male mortality. No large prospective cohort study has determined a possible association between serum estradiol and mortality in men.

OBJECTIVE

The main objective was to examine the association between serum testosterone and estradiol and all-cause mortality in elderly men.

DESIGN, SETTING, AND PARTICIPANTS

We used specific gas chromatography-mass spectrometry to analyze serum sex steroids at baseline in older men who participated in the prospective population-based MrOS Sweden cohort (n = 3014; mean age, 75 yr; range, 69-80 yr).

MAIN OUTCOME MEASURE

All-cause mortality by serum testosterone and estradiol levels.

RESULTS

During a mean follow-up period of 4.5 yr, 383 deaths occurred. In multivariate hazards regression models, low levels (within quartile 1 vs. quartiles 2-4) of both testosterone [hazard ratio (HR), 1.65; 95% confidence interval (CI), 1.29-2.12] and estradiol (HR, 1.54; 95% CI, 1.22-1.95) associated with mortality. A model including both hormones showed that both low testosterone (HR, 1.46; 95% CI, 1.11-1.92) and estradiol (HR, 1.33; 95% CI, 1.02-1.73) predicted mortality. Risk of death nearly doubled (HR, 1.96; 95% CI, 1.46-2.62) in subjects with low levels of both testosterone and estradiol compared with subjects within quartiles 2-4 of both hormones.

CONCLUSIONS

Elderly men with low serum testosterone and estradiol have increased risk of mortality, and subjects with low values of both testosterone and estradiol have the highest risk of mortality.

Assessing symptoms of hypogonadism by self-administered questionnaire: qualitative findings in patients and controls

BACKGROUND

Current screening instruments for hypogonadism lack adequate specificity and diagnostic accuracy. A new self-administered questionnaire of hypogonadism symptoms is being developed to address this need. The process for questionnaire development and results from the first (qualitative) phase are presented.

METHODS

Qualitative interviews were conducted based on a new conceptual model of hypogonadism and according to standards for questionnaire development. An item pool was generated from focus groups and in-depth interviews with two groups of hypogonadal patients, treated (N = 26) and untreated (N = 26), and age-equivalent controls (N = 28). Standardized scoring of the qualitative interviews was used to confirm conceptual domains in the model and to generate questionnaire items for further validation.

RESULTS

Key domains identified in both patients and controls included: (a) physical function; (b) bodily signs and symptoms; (c) sexual function and libido; (d) sleep function; (e) mood and affective function; (f) memory and cognitive function. The final domain is distress or bother associated with hypogonadism symptoms. This domain was only relevant to the patient groups.

CONCLUSIONS

The first stage in the design of a new hypogonadism screener has been completed. Seven domains were identified and draft items were developed in each domain according to current standards of patient-reported outcomes.

The role of testosterone in the metabolic syndrome: a review

Over the last three decades it has become apparent that testosterone plays a significant role in the maintenance of bone and muscle mass, in erythropoiesis, and in mental functions. But testosterone is also a key player in glucose homeostasis and lipid metabolism. The metabolic syndrome is a clustering of risk factors predisposing to late onset diabetes mellitus, atherosclerosis and cardiovascular morbidity and mortality. The main components of the syndrome are visceral obesity, glucose intolerance, raised blood pressure and dyslipidaemia (elevated triglycerides, low levels of high-density lipoprotein cholesterol),and a pro-inflammatory and thrombogenic state. Cross-sectional epidemiological studies have reported a direct correlation between plasma testosterone and insulin sensitivity, and low testosterone levels are associated with an increased risk of type 2 diabetes mellitus, dramatically illustrated by androgen deprivation in men with prostate carcinoma. Lower total testosterone and sex hormone-binding globulin(SHBG) predict a higher incidence of the metabolic syndrome. There is now evidence to argue that hypotestosteronaemia should be an element in the definition of the metabolic syndrome. Administration of testosterone to hypogonadal men reverses the unfavorable risk profile for the development of diabetes and atherosclerosis. Testosterone should be regarded as a pivotal hormone for men's health.

Low serum testosterone and mortality in older men

CONTEXT

Declining testosterone levels in elderly men are thought to underlie many of the symptoms and diseases of aging; however, studies demonstrating associations of low testosterone with clinical outcomes are few.

OBJECTIVE

The objective of the study was to examine the association of endogenous testosterone levels with mortality in older community-dwelling men.

DESIGN, SETTING, AND PARTICIPANTS

This was a prospective, population-based study of 794 men, aged 50-91 (median 73.6) yr who had serum testosterone measurements at baseline (1984-1987) and were followed for mortality through July 2004.

MAIN OUTCOME MEASURE

All-cause mortality by serum testosterone level was measured.

RESULTS

During an average 11.8-yr follow-up, 538 deaths occurred. Men whose total testosterone levels were in the lowest quartile (<241 ng/dl) were 40% [hazards ratio (HR) 1.40; 95% confidence interval (CI) 1.14-1.71] more likely to die than those with higher levels, independent of age, adiposity, and lifestyle. Additional adjustment for health status markers, lipids, lipoproteins, blood pressure, glycemia, adipocytokines, and estradiol levels had minimal effect on results. The low testosterone-mortality association was also independent of the metabolic syndrome, diabetes, and prevalent cardiovascular disease but was attenuated by adjustment for IL-6 and C-reactive protein. In cause-specific analyses, low testosterone predicted increased risk of cardiovascular (HR 1.38; 95% CI 1.02-1.85) and respiratory disease (HR 2.29; 95% CI 1.25-4.20) mortality but was not significantly related to cancer death (HR 1.34; 95% CI 0.89-2.00). Results were similar for bioavailable testosterone.

CONCLUSIONS

Testosterone insufficiency in older men is associated with increased risk of death over the following 20 yr, independent of multiple risk factors and several preexisting health conditions.