Age trends in the level of serum testosterone and other hormones in middle-aged men: longitudinal results from the Massachusetts male aging study

Cardiovascular disease and androgens: a review

Globally, cardiovascular disease is the single largest cause of mortality. The differences in pattern of cardiovascular disease between the two genders have not been explained properly. The spotlight has largely been focused on estrogens but no conclusive evidence has proven its role in reducing the incidence of cardiovascular disease. Consequently, androgens have attracted significant interest in explaining the gender difference in cardiovascular disease. More studies in last two decades have increased our knowledge about the effects of androgens on cardiovascular disease progression. Evidence for age related fall in testosterone levels in males and increasing cardiovascular events with age had lead to the postulation of idea of 'andropause or male menopause'. Unfortunately, for the last few decades the androgens have been highlighted as agents of abuse among athletes all over the world. There have been multiple reports of their association with sudden cardiac death and adverse cardiovascular outcomes when abused. Contrastingly, there has been an increasing prescription use of testosterone supplementation in various conditions related to androgen deficiency state and for many other off-label indications. Human observational studies have mostly concluded that men with lower testosterone levels tend to have higher incidence of coronary artery disease. Emerging evidence supports that lower androgen levels predict poor cardiovascular risk profile. Role with supplementation of testosterone for cardiovascular disease is being studied in both primary and secondary prevention stages and its safety being evaluated. This is an appropriate time to review the role of androgens specifically from a cardiovascular standpoint.

Genetic risk factors for disordered eating in adolescent males and females

The etiologic role of genetic and environmental factors on disordered eating was examined in a sample of 15- to 17-year-old female-female, male-male, and opposite-sex twin pairs. Also assessed was whether a single factor is underlying 3 facets (body dissatisfaction, drive for thinness, bulimia) of disordered eating, including the possible importance of sex differences. Univariate model-fitting analyses indicated that genetic factors are more important for girls and environment more important for boys for body dissatisfaction and drive for thinness. A multivariate common factor analysis indicated that a single factor accounted for the association among these 3 facets of disordered eating in both sexes. However, only 50% of the genetic risk for this factor is shared between the sexes.

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.

Activational effects of sex hormones on cognition in men

BACKGROUND

Changing world demographic patterns, such as the increasing number of older people and the growing prevalence of cognitive impairment, present serious obstacles to preserving the quality of life and productivity of individuals. The severity of dementia varies from subclinical, mild cognitive impairment to neurodegenerative diseases such as Alzheimer's. In normally ageing men, these age-related cognitive declines are accompanied by gradual but marked decreases in androgen levels and changes in other hormone profiles. While developmental effects of sex hormones on cognition in the pre- and early postnatal period have been demonstrated, their activational effects in later life are still a focus of contemporary research. Although there is a plethora of published research on the topic, results have been inconsistent with different studies reporting positive, negative or no effects of sex hormones on various aspects of mental agility.

METHODS

This review summarizes the evidence supporting the biological plausibility of the activational effects of sex hormones upon cognition and describes the mechanisms of their actions. It offers a comprehensive summary of the studies of the effects of sex hormones on fluid intelligence in men utilizing elements from the Cochrane Collaboration Guidelines for Reviews. The results of both observational (cross-sectional and longitudinal) and interventional studies published to date are collated in table form and further discussed in the text. Factors contributing to the difficulties in understanding the effects of sex hormones on cognition are also examined.

CONCLUSIONS

Although there is convincing evidence that steroid sex hormones play an organizational role in brain development in men, the evidence for activational effects of sex hormones affecting cognition in healthy men throughout adult life remains inconsistent. To address this issue, a new multifactorial approach is proposed which takes into account the status of other elements of the sex hormones axis including receptors, enzymes and other hormones.

Salivary sex hormone measurement in a national, population-based study of older adults

OBJECTIVES

To describe the methods used for, correlates of cooperation with, and validity of in-home salivary specimens collected from older adults.

METHODS

Salivary specimens were collected between 2005 and 2006 during in-home interviews with a probability sample of 3,005 U.S. men and women, ages 57-85 years. Sex hormone levels were assessed by enzyme-linked immunoassay conducted at Salimetrics, LLC (State College, PA). Mean salivary sex hormone concentrations were compared by gender and in relation to medication use and health conditions.

RESULTS

Self-collected saliva specimens were provided by 2,722 (90.6%) individuals; 95.8% of these were adequate for analysis. Black participants were significantly less likely than individuals of other racial/ethnic groups to provide a salivary specimen; age, gender, education, and self-rated health were not associated with participation. Mean testosterone levels were higher in men compared with women, and estradiol levels were higher in women using estrogens. Salivary hormone measurements obtained in the National Social Life, Health, and Aging Project (NSHAP) and other studies are of similar magnitude.

CONCLUSION

NSHAP is the first large, population-based study of older adults to measure salivary estradiol, progesterone, dehydroepiandrosterone (DHEA), and, in women, testosterone. These data demonstrate a high cooperation rate with in-home salivary specimen collection from older adults and good validity of sex hormone measurements.

Demographic, physical and lifestyle factors associated with androgen status: the Florey Adelaide Male Ageing Study (FAMAS)

OBJECTIVE

Plasma androgen levels are inversely associated with health in men, the age-related decline of which may result from factors other than ageing per se. This study aimed to determine the effects of demographic, physical and lifestyle factors on age-related androgen status in men.

DESIGN

An observational survey of a regionally representative male population residing in the North West regions of Adelaide, Australia.

PARTICIPANTS

Study sample includes 1195 men aged 35-81 years with a response rate of 45.1%.

MEASUREMENTS

Plasma levels of total testosterone (TT), bioavailable testosterone (BT), SHBG, insulin-like peptide 3 (INSL3), and gonadotrophins were measured along with an extensive list of demographic, physical and lifestyle factors including body composition, muscle strength and biomarkers of chronic diseases, physical activity, nutrition and smoking behaviour.

RESULTS

Low TT was mostly associated with high abdominal fat and triglycerides and low muscle strength rather than ageing per se. Low BT was associated with increased age followed by high whole body fat percentage. BT and TT levels were higher in unmarried men and smokers. SHBG levels increased with age, but were also inversely associated with insulin and triglycerides. The Leydig cell specific factor INSL3 was the strongest biomarker associated with both TT and BT.

CONCLUSIONS

Factors associated with low androgen status variably include high body fat percentage, low muscle strength and biomarkers of the metabolic syndrome. Reducing exposure to factors that adversely affect androgen status may improve the general health of ageing men by mechanisms yet to be defined.

Changes in bone mineral density differ between gonadotrophin‐releasing hormone analogue‐ and surgically castrated men with prostate cancerA prospective, controlled, parallel‐group study

OBJECTIVE

The effects of surgical and medical castration on bone mineral density (BMD) were compared in men receiving castration therapy as a result of prostate cancer. A control group of men of similar age was also included in the study.

MATERIAL AND METHODS

A total of 28 men with prostatic cancer who had been selected to undergo medical or surgical castration and 10 healthy men with benign urological disorders were followed from baseline observations and BMD was assessed at 3, 6, 12 and 36 months. Serum hormone levels were also assessed.

RESULTS

Orchidectomy and treatment with gonadotrophin-releasing hormone (GnRH) analogues caused an expected rapid decrease in serum testosterone levels, with no difference between these two groups. The mean loss of BMD in the femoral neck measured by means of dual-energy X-ray absorptiometry in surgically castrated men and GnRH-treated men was 0.037 g/cm2 (4.53%; SEM 0.013 g/cm2; p = 0.010) and 0.027 g/cm2 (3.18%; SEM 0.014 g/cm2; p = 0.119), respectively at 12 months, while the controls gained 0.017 g/cm2 (1.26%; SEM 0.013 g/cm2; p = 0.195). In the heel, surgically castrated men lost 9.04% of BMD (p < 0.001), the GnRH-treated men lost 3.58% (p = NS) and the controls gained 1.26% (p = NS).

CONCLUSION

We found a more pronounced decrease in BMD in men with metastatic prostate cancer who were treated with surgical castration than in those who were treated with GnRH analogues.

Determination of testosterone in serum by liquid chromatography-tandem mass spectrometry

Commercial direct immunoassays for serum testosterone sometimes result in inaccuracies in samples from women and children, leading to misdiagnosis and inappropriate treatment. The diagnosis of male hypogonadism also requires an accurate testosterone assay method. We therefore developed a sensitive and specific stable-isotope dilution liquid chromatography-tandem mass spectrometric (LC-MS/MS) method for serum testosterone at the concentrations encountered in women and children. Testosterone was extracted with ether-ethyl acetate from 250 microL or 500 microL of serum. Instrumental analysis was performed on an API 2000 tandem mass spectrometer in the multiple-reaction monitoring (MRM) mode after separation on a reversed-phase column. The MRM transitions (m/z) were 289/97 for testosterone and 291/99 for d(2) testosterone. The calibration curves exhibited consistent linearity and repeatability in the range 0.2-100 nmol/L. Interassay CVs were 4.2-7.6 % at mean concentrations of testosterone of 3.3-45 nmol/L. Total measurement uncertainty (U, k = 2) was 12.9 % and 13.4 % at testosterone levels of 2.0 nmol/L and 20 nmol/L, respectively. The limit of detection was 0.05 nmol/L (signal-to-noise ratio = 3) and the overall method recovery of testosterone was 95 %. Correlation (r) with our in-house extraction RIA was 0.98 and with a commercial RIA 0.92. Reference intervals for adult males and females in age groups 18-30, 31-50, 51-70 and over 70 years were established. Sensitivity and specificity of the LC-MS/MS method offer advantages over immunoassay and make it suitable for use as a high-throughput assay in routine clinical laboratories. The high equipment costs are balanced by higher throughput together with shorter chromatographic run times.

Lower testosterone levels predict incident stroke and transient ischemic attack in older men

CONTEXT

Lower circulating testosterone concentrations are associated with metabolic syndrome, type 2 diabetes, carotid intima-media thickness, and aortic and lower limb arterial disease in men. However, it is unclear whether lower testosterone levels predict major cardiovascular events.

OBJECTIVE

We examined whether lower serum testosterone was an independently significant risk factor for symptomatic cerebrovascular events in older men.

DESIGN

This was a prospective observational study with median follow-up of 3.5 yr.

SETTING

Community-dwelling, stroke-free older men were studied.

PARTICIPANTS

A total of 3443 men at least 70 yr of age participated in the study.

MAIN OUTCOME MEASURES

Baseline serum total testosterone, SHBG, and LH were assayed. Free testosterone was calculated using mass action equations. Incident stroke or transient ischemic attack (TIA) was recorded.

RESULTS

A first stroke or TIA occurred in 119 men (3.5%). Total and free testosterone concentrations in the lowest quartiles (<11.7 nmol/liter and <222 pmol/liter) were associated with reduced event-free survival (P = 0.014 and P = 0.01, respectively). After adjustment including age, waist-hip ratio, waist circumference, smoking, hypertension, dyslipidemia, and medical comorbidity, lower total testosterone predicted increased incidence of stroke or TIA (hazard ratio = 1.99; 95% confidence interval, 1.33-2.99). Lower free testosterone was also associated (hazard ratio = 1.69; 95% confidence interval, 1.15-2.48), whereas SHBG and LH were not independently associated with incident stroke or TIA.

CONCLUSIONS

In older men, lower total testosterone levels predict increased incidence of stroke or TIA after adjusting for conventional risk factors for cardiovascular disease. Men with low-normal testosterone levels had increased risk. Further studies are warranted to determine whether interventions that raise circulating testosterone levels might prevent cerebrovascular disease in men.

Low body mass index and declining sex steroids explain most age-related bone loss in Brazilian men

SUMMARY

Osteoporosis in men is underestimated, but our data point to an increasing prevalence rate in those over 70 years old with body mass index (BMI) <25 kg/m(2), bioavailable testosterone <2.7 nmol/L, bioavailable estradiol <40 pmol/L, and high bone turnover, defined in this study as serum carboxyterminal cross-linked telopeptide of type I collagen (ICTP) >4.3 microg/L.

INTRODUCTION

The association of sex steroids and osteoporosis was evaluated in 104 men, aged 50-93 years old.

METHODS

Bone mineral density (BMD), bone turnover (ICTP), testosterone (T), and estradiol (E(2)) were measured; free and bioavailable hormones (free testosterone index [FTI], BioT, free estradiol index [FEI], and BioE(2)) were calculated from T, E(2), sex hormone-binding globulin (SHBG), and albumin. Nonparametric analysis and Poisson regression models were used.

RESULTS

Significant increases in SHBG and ICTP and decreases in femoral neck BMD, FTI, FEI, BioT, and BioE(2) were observed with each additional decade of age. Femoral neck BMD was inversely correlated with ICTP, and both were significantly associated with SHBG, FTI, BioT, FEI, and BioE. There was a direct and graded association between age and osteoporosis prevalence rate (OP PR; p = 0.028). Compared to participants less than 70 years old, the crude OP PR of those 80 years and older was 3.2 (95%CI = 1.4-7.3). Adjusting sequentially for BMI and bioavailable sex hormones attenuated the association between age and osteoporosis prevalence by 55% and 77%, respectively.

CONCLUSION

Our data support the view that low BMI and declining sex steroids explain most of the association between aging, increased bone turnover, and osteoporosis in men.

Protective actions of sex steroid hormones in Alzheimer's disease

Risk for Alzheimer's disease (AD) is associated with age-related loss of sex steroid hormones in both women and men. In post-menopausal women, the precipitous depletion of estrogens and progestogens is hypothesized to increase susceptibility to AD pathogenesis, a concept largely supported by epidemiological evidence but refuted by some clinical findings. Experimental evidence suggests that estrogens have numerous neuroprotective actions relevant to prevention of AD, in particular promotion of neuron viability and reduction of beta-amyloid accumulation, a critical factor in the initiation and progression of AD. Recent findings suggest neural responsiveness to estrogen can diminish with age, reducing neuroprotective actions of estrogen and, consequently, potentially limiting the utility of hormone therapies in aged women. In addition, estrogen neuroprotective actions are also modulated by progestogens. Specifically, continuous progestogen exposure is associated with inhibition of estrogen actions whereas cyclic delivery of progestogens may enhance neural benefits of estrogen. In recent years, emerging literature has begun to elucidate a parallel relationship of sex steroid hormones and AD risk in men. Normal age-related testosterone loss in men is associated with increased risk to several diseases including AD. Like estrogen, testosterone has been established as an endogenous neuroprotective factor that not only increases neuronal resilience against AD-related insults, but also reduces beta-amyloid accumulation. Androgen neuroprotective effects are mediated both directly by activation of androgen pathways and indirectly by aromatization to estradiol and initiation of protective estrogen signaling mechanisms. The successful use of hormone therapies in aging men and women to delay, prevent, and or treat AD will require additional research to optimize key parameters of hormone therapy and may benefit from the continuing development of selective estrogen and androgen receptor modulators.

The benefits and risks of testosterone replacement therapy: a review

Increased longevity and population aging will increase the number of men with late onset hypogonadism. It is a common condition, but often underdiagnosed and undertreated. The indication of testosterone-replacement therapy (TRT) treatment requires the presence of low testosterone level, and symptoms and signs of hypogonadism. Although controversy remains regarding indications for testosterone supplementation in aging men due to lack of large-scale, long-term studies assessing the benefits and risks of testosterone-replacement therapy in men, reports indicate that TRT may produce a wide range of benefits for men with hypogonadism that include improvement in libido and sexual function, bone density, muscle mass, body composition, mood, erythropoiesis, cognition, quality of life and cardiovascular disease. Perhaps the most controversial area is the issue of risk, especially possible stimulation of prostate cancer by testosterone, even though no evidence to support this risk exists. Other possible risks include worsening symptoms of benign prostatic hypertrophy, liver toxicity, hyperviscosity, erythrocytosis, worsening untreated sleep apnea or severe heart failure. Despite this controversy, testosterone supplementation in the United States has increased substantially over the past several years. The physician should discuss with the patient the potential benefits and risks of TRT. The purpose of this review is to discuss what is known and not known regarding the benefits and risks of TRT.

Androgens and Alzheimer's disease

PURPOSE OF REVIEW

To discuss the relationship between androgens, cognition and Alzheimer's disease.

RECENT FINDINGS

It has been found that low circulating levels of androgens are a risk factor for Alzheimer's disease. Decreased circulating androgens are also associated with declining cognitive performance, particularly in memory-related tasks. Conversely, androgen supplementation to hypogonadal men results in improved memory performance. It has therefore been hypothesized that androgen supplementation may be beneficial in Alzheimer's disease. In recent studies, animal models have been used to elucidate the molecular mechanism behind this relationship between androgens and Alzheimer's disease. These studies have shown that androgen depletion results in increased levels of beta amyloid and hyperphosphorylated tau, changes which are thought to be associated with subsequent neuronal death.

SUMMARY

Androgen depletion results in molecular changes associated with Alzheimer's disease. Further human trials are needed to determine whether androgen modulating therapy for Alzheimer's disease has clinical significance.

Age-related changes in sex steroid levels influence bone mineral density in healthy Indian men

SUMMARY

Age-related changes in sex steroid levels and its contribution to variations in rate of bone loss among men is unclear. Although, Bio-T and Bio-E(2) levels declined with age and depicted an association with BMD in healthy Indian men, Bio-E(2) was found to be an independent predictor of BMD.

INTRODUCTION

Ethnicity influences sex steroid levels, therefore, their role in pathogenesis of low bone mass needs to be established in various populations. We assessed the extent of changes in sex steroid levels with age and related these to bone mineral density (BMD) in healthy Indian men.

METHODS

Total testosterone (TT), estradiol (E(2)), sex hormone-binding globulin (SHBG), PTH, osteocalcin (OC), and c-terminal telopeptide (CTX) were measured in 330 men aged 20-55 years and correlated with BMD measured by DXA.

RESULTS

Both Bio-T (1% per year) and Bio-E(2) (0.8% per year) levels decreased significantly in ageing men, whereas TT (0.4% per year) and E(2) (0.3% per year) levels decreased only marginally with age. In contrast, SHBG (1.4% per year) and PTH (1% per year) levels increased significantly with age. Serum TT (r = 0.19, p = 0.01) and Bio-T (r = 0.2, p = 0.01) levels were associated positively with BMD at spine, whereas E(2) and Bio-E(2) levels were associated with BMD at spine [E (2) (r = 0.31, p < 0.0001); Bio-E(2) r = 0.37, p < 0.0001] and femur (E(2) r = 0.26, p = 0.001; Bio-E(2) r = 0.27, p = 0.001). Men in the lowest quartile of Bio-E(2) were associated with lower BMD and higher bone turnover.

CONCLUSIONS

Age-related decrease in bioavailable sex steroid levels is associated with BMD in healthy Indian men. Bio-E(2) was found to be an independent predictor of BMD.

Testosterone therapy in men

Androgens exert effects on virtually all bodily tissues, and have a multitude of physiological roles in health. Testosterone, the predominant androgen in men, when deficient (hypogonadism), leads to a multiplicity of symptoms and signs that are corrected with physiological substitution. The impact of hypogonadism depends on the age at which it occurs. In any case, when testosterone replacement is initiated close monitoring for efficacy and safety is advised. The relation of ageing, the metabolic syndrome, type 2 diabetes, obesity and survival with plasma testosterone has been closely examined in recent studies. However, the effect of testosterone replacement therapy on the above clinical states needs to be clarified in large long-term duration/outcome studies. Recent research has shed light on possible molecular testosterone targets. Based on those research outcomes, drugs targeting the androgen receptor, which spare androgenic effects and preserve anabolic tissue effects, called selective androgen receptor modulators (SARMS), are under clinical trials. The role of testosterone in regulating erectile function has been studied in animal models and critical tissue testosterone targets have been elucidated.

Salivary cortisol output before and after cognitive behavioural therapy for chronic fatigue syndrome

BACKGROUND

There is evidence that patients with chronic fatigue syndrome (CFS) have mild hypocortisolism. One theory about the aetiology of this hypocortisolism is that it occurs late in the course of CFS via factors such as inactivity, sleep disturbance, chronic stress and deconditioning. We aimed to determine whether therapy aimed at reversing these factors--cognitive behavioural therapy for CFS--could increase cortisol output in CFS.

METHODS

We measured diurnal salivary cortisol output between 0800 and 2000 h before and after 15 sessions (or 6 months) of CBT in 41 patients with CDC-defined CFS attending a specialist, tertiary outpatient clinic.

RESULTS

There was a significant clinical response to CBT, and a significant rise in salivary cortisol output after CBT.

LIMITATIONS

We were unable to control for the passage of time using a non-treated CFS group.

CONCLUSIONS

Hypocortisolism in CFS is potentially reversible by CBT. Given previous suggestions that lowered cortisol may be a maintaining factor in CFS, CBT offers a potential way to address this.

Prevalence of low male testosterone levels in primary care in Germany: cross-sectional results from the DETECT study

OBJECTIVE

Low testosterone levels in men occur with increasing age and are associated with increased morbidity, particularly metabolic syndrome, and mortality. As the prevalence of hypogonadal testosterone levels has not been assessed in the primary care setting in Europe, we aimed to investigate the prevalence of low testosterone levels in this setting, and the patient characteristics and comorbidities associated with this finding.

DESIGN

A cross-sectional, epidemiological study (the Diabetes Cardiovascular Risk-Evaluation: Targets and Essential Data for Commitment of Treatment (DETECT) study).

PATIENTS

A total of 2719 male primary care patients (age 58.7 +/- 13.4 years) were included.

MEASUREMENTS

Testosterone was measured in all patients. Information on diseases, risk conditions and treatments was documented by the primary care physicians. A large set of laboratory parameters was measured in a central laboratory. We calculated univariate and multivariate logistic regression models to assess the associations of low testosterone levels with different health and life style factors.

RESULTS

A total of 19.3% of all men had hypogonadism as defined by testosterone levels < 3.0 ng/ml. Stepwise logistic regression analysis revealed that obesity, metabolic syndrome, cancer, intake of six or more drugs, acute inflammation and nonsmoking were associated with hypogonadal testosterone levels. Higher age, liver diseases, and cancer were associated with very low testosterone levels (< 1.0 ng/ml).

CONCLUSIONS

Hypogonadal testosterone levels are common in primary care, particularly in patients with the above conditions.

Healthier lifestyle predicts higher circulating testosterone in older men: the Health In Men Study

OBJECTIVE

Circulating testosterone declines during male ageing, and low testosterone may predispose to ill health. We sought to determine whether greater participation in healthy behaviours predicted reduced risk of subsequent lower circulating testosterone in older men.

DESIGN

Cross-sectional analysis of a population-based follow-up study.

PARTICIPANTS

A total of 3453 men aged 65-83 years.

MEASUREMENTS

Lifestyle score, a tally of eight prudent health-related behaviours, was determined during 1996-99. Early morning sera collected in 2001-04 were assayed for total testosterone, SHBG and LH. Free testosterone was calculated using mass action equations.

RESULTS

Mean (+/- SD) time between collection of lifestyle data and blood sampling was 5.7 +/- 0.9 years. Lifestyle score correlated with subsequent total testosterone (r = 0.06, P < 0.001) and SHBG (r = 0.07, P < 0.001), but not free testosterone (r = 0.03, P = 0.08) or LH (r = -0.03, P = 0.12). In multivariate analyses, higher lifestyle scores (4 and above) predicted reduced risk of total testosterone and SHBG in the lowest quartile of values. For the highest category (>or= 7), odds ratio (95% CI) for total testosterone and SHBG in the lowest quartile were 0.37 (0.18-0.77) and 0.26 (0.13-0.54), respectively. Lower lifestyle scores including and excluding body mass index predicted higher risk of total testosterone and SHBG in the lowest quartiles.

CONCLUSIONS

In men > 65 years old, higher lifestyle score reflecting greater engagement in healthy behaviours predicts higher subsequent total testosterone and SHBG levels. This relationship appears cumulative and may reflect interaction between lifestyle and insulin sensitivity. Successfully promoting healthy behaviours in older men could ameliorate the age-related decline in circulating testosterone.

Age-related changes in hypothalamic androgen receptor and estrogen receptor alpha in male rats

The control of reproductive function involves actions of sex steroids upon their nuclear receptors in the hypothalamus and preoptic area (POA). Whether hypothalamic hormone receptors change their expression in aging male mammals has not been extensively pursued, although such changes may underlie functional losses in reproductive physiology occurring with aging. We performed a stereologic analysis of immunoreactive androgen receptor (AR) and estrogen receptor alpha (ERalpha) cells in three POA nuclei of male Sprague-Dawley rats (anteroventral periventricular nucleus [AVPV], median preoptic area [MePO], and medial preoptic nucleus [MPN]), at young (3 months), middle-aged (12 months), and old (20 months) ages. Serum testosterone and estradiol levels were assayed. Testosterone concentrations decreased significantly and progressively with aging. Estradiol concentrations were significantly higher in middle-aged than either young or old rats. Stereologic analyses of the POA demonstrated that AR-immunoreactive cell numbers and density in the AVPV, MePO, and MPN were significantly higher in old compared with young or middle-aged rats. No change in the total number or density of ERalpha-immunoreactive cells was detected with age, although when cells were subdivided by intensity of immunolabeling, the most heavily labeled ERalpha cells increased in number with aging in the AVPV and MePO, and in density in the AVPV. There are several interpretations to our finding of substantially increased AR cell numbers during aging, including a potential compensatory upregulation of the AR under diminished testosterone concentrations. These results provide further information about how the neural targets of steroid hormones change with advancing age.

Androgen deficiency: effects on body composition

Published data on the effects of androgen deficiency and testosterone administration on body composition in men and women are reviewed. In experimental paradigms, androgen deprivation decreases lean body mass and increases fat mass in men, and physiologic replacement reverses these abnormalities. The anabolic effects of testosterone administration on muscle in men are well-established, and current understanding of the underlying mechanisms are discussed. Randomized, placebo-controlled studies have been performed to investigate the effects of testosterone administration on body composition in a number of male hypogonadal states, including HIV-associated weight loss, supraphysiologic glucocorticoid administration, aging and obesity, with variable outcomes, and the results are reviewed. There are few data investigating the effects of hypoandrogenemia or androgen replacement on body composition in women, in whom endogenous testosterone levels are a fraction of those in men. A recent randomized, placebo-controlled study of physiologic testosterone replacement therapy in women with profound hypoandrogenemia due to hypopituitarism demonstrated an increase in skeletal muscle mass but no change in body fat. Further research is needed to establish the effects of endogenous androgens on the regulation of body composition in women.

Association between testosterone and estradiol and age-related decline in physical function in a diverse sample of men

OBJECTIVES

To examine the association between aging and physical function in men by testing a theoretically based model of aging, hormones, body composition, strength, and physical function with data obtained from men enrolled in the Boston Area Community Health/Bone (BACH/Bone) Survey.

DESIGN

Cross-sectional, observational survey.

SETTING

Population-based.

PARTICIPANTS

Eight hundred ten black, Hispanic, and white randomly selected men from the Boston area aged 30 to 79.

MEASUREMENTS

Testosterone, estradiol, sex hormone-binding globulin, lean and fat mass, grip strength, and summated index of physical function (derived from walk and chair stand tests).

RESULTS

Measures of grip strength and physical function declined strongly with age. For instance, 10 years of aging was associated with a 0.49-point difference (scale 0-7) in physical function. Age differences in total testosterone and estradiol concentrations were smaller than age differences in their free fractions. Weak or nonsignificant age-adjusted correlations were observed between hormones and measures of physical function, although path analysis revealed a positive association between testosterone and appendicular lean mass and a strong negative association between testosterone and total fat mass. Lean and fat mass, in turn, were strongly associated with grip strength and physical function, indicating the possibility that testosterone influences physical function via indirect associations with body composition.

CONCLUSION

The age-related decline in serum testosterone concentration in men has a weak association with physical strength and functional outcomes through its associations with lean and fat mass.

Type 2 diabetes-associated androgen alteration in patients with erectile dysfunction

Our objective was to assess the pattern of type-2 diabetes-associated androgen alteration in patients with erectile dysfunction (ED). A total of 127 diabetic male patients with ED were enrolled in this study. Erectile function was assessed using the International Index of Erectile Function (IIEF). At the time of assessment, patients were also interviewed and assessed for socio-demographic and medical history that includes duration and severity of diabetes mellitus (DM). Patients underwent routine laboratory investigations, in addition to total testosterone (T), dehydroepiandrosterone sulphate (DHEA-S) and insulin assessment. The mean age +/- SD was 53.8 +/- 9.3 years. Of patients 25.2% (n = 32/127), 6.3% (n = 8/127) and 31.5% (n = 40/127) had low total T, low DHEA-S and hyperinsulinaemia respectively. There were significant association between the increase in age and body mass index and the presence of low T level. Of the patients 37.5% (n = 12/32) with low T level had glycosylated haemoglobin (HbA1c) >7% while, 22.1% (n = 21/95) of the patients with normal T level had HbA1c >7% (p < 0.05). There were significant associations between the number of patients with low level of total T or DHEA-S and poor control of DM. Patients with low T level were two times more likely (56.3%, n = 18/32) to have severe ED than patients with normal T level (27.4%, n = 26/95) (p < 0.01). There were significant differences between the mean levels of total T or DHEA-S and poor control of DM. No significant associations were detected between hyperinsulinaemia and the level of fasting blood sugar, duration of DM, metabolic control of DM or ED severity. Patients with low T level were three times as likely to have hyperinsulinaemia as those patients with normal T level (p < 0.05). The current study clearly demonstrated that there were significant associations between low level of total T or DHEA-S and poor control of DM.

Decline of plasma 5alpha-dihydrotestosterone (DHT) levels upon testosterone administration to elderly men with subnormal plasma testosterone and high DHT levels

The study was performed to measure the impact of testosterone (T) administration on circulating levels of 5alpha-dihydrotestosterone (DHT). Group 1 (32 men; mean age 61 years; mean T 6.9 +/- 1.9 nmol l(-1)) were treated for 15 months with long-acting T undecanoate. Group 2 (23 men, mean age 60 years, mean T 7.6 +/- 2.0 nmol l(-1)) were treated for 9 months with T gel. Plasma T and DHT were measured before and after 9 months T administration. In the men treated with T undecanoate plasma T and DHT were also measured after 12 and 15 months. Before T administration, plasma DHT ranged from 0.39 to 1.76 nmol l(-1) (0.30-1.90 nmol l(-1)). Mean DHT declined upon T administration from 0.95 +/- 0.50 to 0.55 +/- 0.30 nmol l(-1) (P < 0.05). With an arbitrary cut-off at 0.60 nmol l(-1), all 21 values of DHT > 0.60 nmol l(-1) had fallen from 1.29 +/- 0.50 to 0.70 +/- 0.60 nmol l(-1) (P < 0.01). Below this cut-off point 13 values rose and 21 fell upon T administration. Below this cut-off point values on average declined from 0.39 +/- 0.12 to 0.30 +/- 0.14 nmol l(-1) (P < 0.05). The study revealed that in a cohort of elderly men with subnormal plasma T levels plasma DHT levels declined upon T administration when they were in the higher range of normal (>0.6 nmol l(-1)), with a profound shift of DHT/T ratios presumed to be an indicator of a reduced 5alpha-reductase activity. Below plasma DHT levels of 0.6 nmol l(-1), responses of plasma DHT to T administration varied.

Elevated Serum Estradiol/Testosterone Ratio in Men with Primary Varicose Veins Compared with a Healthy Control Group

The role of sex hormones in men with varicose veins remains unclear. Therefore, we set up a prospective pilot-study. In 34 men, venous blood was sampled during morning hours, for the determination of serum estradiol (E2), dehydroepiandrostendion, androstendion, and free testosterone (fT). Serum E2:fT ratio was calculated. The study protocol also included patient history, physical examination, color duplex ultrasound of both limbs, and assignment of CEAP clinical stage (C) classification. About 21 symptomatic varicose men (VM [C ≥ 2] mean age of 40.3/±6.9 years) and 13 healthy men (HM [C ≤ 1] mean age of 38.1/± 7.4 years) were analyzed. The serum E2:fT ratio (VM 2.83/± 0.79 and HM 2.32/±0.63) was significantly different ( P < .05) between the two groups. No major differences were seen on the serum levels of the sex hormones. In summary, our results demonstrate a changed serum E2:fT ratio among men with varicose veins compared to healthy men. By the fact of a small study sample, the interpretabillity of this result is limited.

Serum testosterone and bioavailable testosterone correlate with age and body size in hypogonadal men treated with testosterone undecanoate (1000 mg IM--Nebido)

OBJECTIVE

To investigate the loading regimen for intramuscular (IM) testosterone undecanoate (Nebido) to determine whether testosterone and bioavailable testosterone levels achieved correlate with age or body size of subjects studied.

DESIGN

Retrospective observational study of testosterone naïve patients and patients previously treated with an alternative testosterone therapy.

PATIENTS

51 hypogonadal men (35, 68.6% secondary hypogonadism). 8 (16%) had not previously received testosterone therapy.

MEASUREMENTS

Patients received an IM injection of Nebido (1000 mg) at baseline and a second injection after 6 weeks. Serum was assayed at baseline and 18 weeks after commencing Nebido for total testosterone (TT) and SHBG. Bioavailable testosterone was calculated (cBioT) using TT and SHBG. Measurements were taken for weight, body mass index (BMI) and body surface area (BSA).

RESULTS

Baseline TT (mean 11.5 nmol/l, range 0.3-54.8) increased by 50% after commencing Nebido (17.2 nmol/l (5.4-32.8), P = 0.0001). 75% of subjects had a TT within the reference range (8.0-25.0 nmol/l). Subjects with primary hypogonadism had a higher 18-week TT [20.9 nmol/l (9.8-32.8) vs. 15.5 (5.4-32.6), P = 0.02] and SHBG [39.2 nmol/l (11-82) vs. 25.7 (9.0-60.0), P = 0.003] although the cBioT was not significantly different [4.9 nmol/l (2.9-7.3) vs. 4.2 (2.0-7.9), P = 0.12]. The 18-week TT positively correlated with age (R = 0.36, P = 0.01) and negatively correlated with weight (R = -0.38, P = 0.006), BMI (R = -0.42, P = 0.002) and BSA (R =-0.38, P = 0.007). Similarly cBioT correlated with age (R = 0.28, P = 0.04), weight (R = -0.29, P = 0.03), BMI (R = -0.30, P = 0.03) and BSA (R = -0.27, P = 0.05). Age (t = 2.04, P = 0.05) and baseline testosterone (t = -9.26, P < 0.0001) were independent variables of the increase in TT at 18 weeks.

CONCLUSION

This starting regimen is simple and provides the majority of men with a TT within the reference range. Age and baseline TT are independent variables of the increase in TT with IM testosterone undecanoate. At week 18 age and body size correlated with the cBioT and TT and this may then be used to estimate dosing frequency for this therapy.

Correlates of low testosterone and symptomatic androgen deficiency in a population-based sample

CONTEXT

Risk factors for low testosterone and symptomatic androgen deficiency (AD) may be modifiable.

OBJECTIVE

Our objective was to examine demographic, anthropometric, and medical correlates of low testosterone and symptomatic AD.

DESIGN

Data were used from the Boston Area Community Health Survey, an epidemiological study conducted from 2002-2005.

SETTING

Data were obtained from a community-based random sample of racially and ethnically diverse men.

PATIENTS OR OTHER PARTICIPANTS

Data were available for 1822 men.

MAIN OUTCOME MEASURES

Multivariate logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for associations of covariates with 1) low testosterone and 2) symptomatic AD. The operational definition of low testosterone was serum total testosterone less than 300 ng/dl and free testosterone less than 5 ng/dl; symptomatic AD was defined as the additional presence of symptoms: any of low libido, erectile dysfunction, or osteoporosis or two or more of sleep disturbance, depressed mood, lethargy, or diminished physical performance.

RESULTS

Factors associated with low testosterone included age (OR = 1.36; 95% CI= 1.11-1.66, per decade), low per-capita income ($6000 or less per household member vs. more than $30,000; OR = 2.86; 95% CI = 1.39-5.87), and waist circumference (per 10-cm increase; OR = 1.75; 95% CI = 1.45-2.12). Only age (OR = 1.36; 95% CI = 1.04-1.77), waist circumference (OR = 1.88; 95% CI = 1.44-2.47), and health status (OR = 0.21; 95% CI = 0.05-0.92, excellent vs. fair/poor) were associated with our construct of symptomatic AD. Of all variables, waist circumference was the most important contributor in both models.

CONCLUSIONS

Waist circumference is a potentially modifiable risk factor for low testosterone and symptomatic AD. Manifestation of symptoms may be a consequence of generally poor health status.

Testosterone levels among men with spinal cord injury: relationship between time since injury and laboratory values

OBJECTIVES

The objectives of the present study were to determine the prevalence of low testosterone among a sample of men with spinal cord injury and to examine the relationship among testosterone, time since injury, and select laboratory values.

DESIGN

Participants were 102 men with spinal cord injury participating in inpatient or outpatient rehabilitation. Data included total serum testosterone level, demographic and injury information, and laboratory values.

RESULTS

Sixty percent of men with spinal cord injury had low testosterone levels. The median testosterone level for the entire sample was 220 ng/dl (normal reference range = 241-827 ng/dl). Low testosterone was significantly associated with less time since injury, lower hemoglobin, and higher prolactin in the univariate analyses at P < 0.05.

CONCLUSIONS

The results indicate that men with spinal cord injury are at risk for low serum testosterone. Testosterone levels were also related to time since injury and hemoglobin and prolactin levels. These findings suggest the need for changes to occur in clinical practice. Guidelines are needed for when and how often testosterone monitoring should be conducted. Future research should address the pathophysiology of low testosterone and the outcomes of testosterone treatment.

Testosterone therapy in hypogonadal men and potential prostate cancer risk: a systematic review

This paper provides a systematic review of the literature about prostate cancer risk associated with testosterone therapy for hypogonadism. A comprehensive search of MEDLINE, EMBASE and other resources was conducted to identify articles that highlight occurrences of prostate cancer in men receiving testosterone therapy for hypogonadism treatment. Articles that met study inclusion criteria were assessed for causality between testosterone treatment and prostate cancer, increased prostate-specific antigen or abnormal digital rectal examination findings. Of 197 articles relating to testosterone therapy, 44 met inclusion criteria: 11 placebo-controlled, randomized studies; 29 non-placebo-controlled studies of men with no prostate cancer history; and 4 studies of hypogonadal men with history of prostate cancer. Of studies that met inclusion criteria, none demonstrated that testosterone therapy for hypogonadism increased prostate cancer risk or increased Gleason grade of cancer detected in treated vs untreated men. Testosterone therapy did not have a consistent effect on prostate-specific antigen levels.

Inverse association of testosterone and the metabolic syndrome in men is consistent across race and ethnic groups

CONTEXT

Low sex hormone levels have been associated with the metabolic syndrome (MetS).

OBJECTIVES

Our objective was to determine whether the association between sex hormone levels and MetS varies by race/ethnicity among men and to investigate the relationship of sex hormones and individual components of MetS.

DESIGN

We conducted a population-based observational survey.

PARTICIPANTS

A multistage stratified design was used to recruit a random sample of 2301 racially/ethnically diverse men age 30-79 yr. Blood samples were obtained on 1899 men. Analyses were conducted on 1885 men with complete data on total testosterone (T), free T, and SHBG.

INTERVENTIONS

There were no interventions.

MAIN OUTCOME MEASURE

MetS was defined using a modification of the Adult Treatment Panel III guidelines. The association between MetS and sex hormone levels was assessed using odds ratios and 95% confidence intervals estimated using logistic regression models.

RESULTS

A strong inverse association was observed, in both bivariate and multivariate analyses, between hormone levels and MetS. The odds of MetS increased about two-fold with a 1 sd decrease in hormone levels. The association between sex hormones and MetS was statistically significant across racial/ethnic groups. Although the magnitude of this association was largest among White men, racial/ethnic differences were not statistically significant. The strength of the association of sex hormones with individual components of MetS varied; stronger associations were observed with waist circumference and dyslipidemia and more modest associations with diabetes and elevated blood sugar.

CONCLUSIONS

A robust, dose-response relationship between sex hormone levels and odds of the metabolic syndrome in men is consistent across racial/ethnic groups.

Hypogonadism is common in men with myopathies

BACKGROUND

Hypogonadism has been described in patients with myotonic muscular dystrophy type 1 but has not been evaluated in other myopathies.

METHODS

We measured total and free serum testosterone levels in 59 men with myotonic muscular dystrophy type 1 (N = 12), facioscapulohumeral muscular dystrophy (N = 11), dystrophinopathy (N = 12), metabolic myopathy (N = 7), and inclusion body myositis (N = 17) and compared these with the normal reference interval.

RESULTS

Thirty-two of the 59 (54%) participants had low total testosterone, 23 (39%) had low total and free values, and 5 (8%) had low free with normal total levels. There were no significant differences in the prevalence of hypogonadism between those with myotonic muscular dystrophy type 1 and the other groups even after considering age as a confounder.

CONCLUSIONS

Hypogonadism is common in men with myopathies, and with the importance of testosterone in the maintenance of muscle mass, treatment of hypogonadism should be considered.

Gender and the injured brain

Anesthesiologists are frequently confronted with patients who are at risk for neurological complications due to perioperative stroke or prior traumatic brain injury. In this review, we address the growing and fascinating body of data that suggests gender and sex steroids influence the pathophysiology of injury and outcome for these patients. Cerebral ischemia, traumatic brain injury, and epilepsy are reviewed in the context of potential sex differences in mechanisms and outcomes of brain injury and the role of estrogen, progesterone, and androgens in shaping these processes. Lastly, implications for current and future perioperative and intensive care are identified.

Serum testosterone levels correlate with haemoglobin in middle-aged and older men

BACKGROUND

Lower testosterone levels are associated with anaemia in older men and women. The relation between testosterone and haemoglobin (Hb) in younger and middle-aged men is less well defined. The aim of the study was to examine the association between testosterone and Hb levels in men spanning middle to older ages.

METHODS

A cross-sectional analysis of 492 men aged 30.7-94.5 years from the Busselton Health Survey, Western Australia, was carried out. Haemoglobin (Hb), early-morning serum total testosterone and sex hormone-binding globulin (SHBG) were measured. Free testosterone was calculated using mass action equations.

RESULTS

Haemoglobin correlated to total and free testosterone concentrations (r= 0.13, P= 0.003 and r= 0.20, P < 0.001, respectively). Hb and SHBG were inversely correlated (r=-0.14, P= 0.001). Hb increased across lowest to highest quartiles of total testosterone (P= 0.02) and free testosterone (P < 0.001), but not SHBG. After adjusting for age, waist circumference, smoking status, alcohol consumption, renal function and ferritin, total testosterone was associated with Hb (beta= 0.037, P= 0.003) as was free testosterone (beta= 2.32, P < 0.001), whereas SHBG was not associated.

CONCLUSION

Testosterone concentration modulates Hb levels in community-dwelling men across a wide age range. Further studies are needed to clarify implications of this association between testosterone and Hb in men.

Persistence of androgenic effects on the production of proinflammatory cytokines by circulating antigen-presenting cells after withdrawal of testosterone treatment in aging type 2 diabetic men with partial androgen deficiency

OBJECTIVE

To test the hypothesis that T treatment withdrawal could be associated with an enhancement of proinflammatory cytokine production by peripheral blood monocytes and dendritic cells.

DESIGN

A prospective intervention study.

SETTING

Tertiary university hospital.

PATIENT(S)

Thirteen type 2 diabetic men aged >55 years with partial androgen deficiency and eight age-matched healthy men (controls).

INTERVENTION(S)

Analyses were performed before and 12 months after T replacement therapy and the results compared with those obtained for the same patients after a 3-month T withdrawal period.

MAIN OUTCOME MEASURE(S)

Distribution of circulating T, B, and natural killer lymphocytes, monocytes, and CD33(hi) myeloid, CD16+, and plasmacytoid dendritic cell subsets. Spontaneous and stimulated ex vivo production of inflammatory cytokines (interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha) by circulating monocytes and dendritic cells, which represent the most potent antigen-presenting cells.

RESULT(S)

The reduction or complete abrogation of spontaneous ex vivo production of proinflammatory cytokines by monocytes and dendritic cells observed after 12 months of T replacement therapy was maintained 3 months after T withdrawal.

CONCLUSION(S)

These are the first results showing that exogenous T treatment deprivation is not associated with an immunologic enhancement of proinflammatory cytokine production by antigen-presenting cells.

The association of testosterone levels with overall sleep quality, sleep architecture, and sleep-disordered breathing

CONTEXT

Little is known about the association of low endogenous testosterone levels and abnormal sleep patterns in older men, although pharmacological doses of testosterone are associated with increased severity of sleep apnea and other sleep disturbances.

OBJECTIVE

The objective of the study was to examine the association between serum testosterone levels with objectively measured sleep characteristics.

DESIGN

This was a cohort study.

SETTING

Community-dwelling men aged 65 yr or older from six clinical centers in the United States participated in the study.

PARTICIPANTS AND MAIN OUTCOME MEASURES

A total of 1312 men had baseline total testosterone levels measured in 2000-2002, followed 3.4 yr later by 72-h (minimum) actigraphy and one-night in-home polysomnography to assess sleep duration, sleep fragmentation, and sleep apnea. Analyses were performed by quartile of total testosterone and categorically defined low vs. higher total testosterone (<250 ng/dl vs. > or =250 ng/dl). Lifestyle and body size were covariates.

RESULTS

Total testosterone levels were unrelated to age or duration of sleep. Men with lower testosterone levels had lower sleep efficiency, with increased nocturnal awakenings and less time in slow-wave sleep as well as a higher apnea-hypopnea index and more sleep time with O(2) saturation levels below 90%. Low testosterone levels were associated with overweight, and all significant associations were attenuated or absent after adjusting for body mass index or waist circumference. In a post hoc analysis in men with higher body mass index (>27 kg/m2), testosterone was significantly associated with more periods awake after sleep onset and lower sleep efficiency.

CONCLUSION

Low total testosterone levels are associated with less healthy sleep in older men. This association is largely explained by adiposity. Clinical trials are necessary to determine whether body weight acts directly or indirectly (via low testosterone) in the causal pathway for sleep-disordered breathing in older men.