Effects of testosterone replacement in hypogonadal men

Muscle mass has a greater impact on serum creatinine levels in older males than in females

Background and aims

We analyzed the effects of age and sex on the relationship between muscle mass and serum creatinine levels in an apparently healthy population, including older adults.

Materials and methods

We retrospectively evaluated 1,502 individuals from the Korea National Health and Nutrition Examination Survey (KNHANES) and 4,586 individuals from the Health Check (HC) groups. We utilized data from the KNHANES and HC groups on serum creatinine levels and skeletal muscle mass index (SMI), determined using dual X-ray absorptiometry or bioelectric impedance analysis.

Results

A significant negative correlation between SMI and age was observed in both the KNHANES and HC groups in males but not in females. In males, serum creatinine levels showed a significant negative correlation with age in both the KNHANES (r = -0.522, P < 0.0001) and HC groups (r = -0.451, P < 0.0001). In females, there was no significant correlation between serum creatinine levels and age in the KNHANES (r = -0.016, P = 0.5985) and HC group (r = -0.011, P = 0.5618).

Conclusions

Serum creatinine levels decrease more significantly in older males than in older females due to sex-specific muscle mass decline.

Bone health in ageing men

Osteoporosis does not only affect postmenopausal women, but also ageing men. The burden of disease is projected to increase with higher life expectancy both in females and males. Importantly, osteoporotic men remain more often undiagnosed and untreated compared to women. Sex steroid deficiency is associated with bone loss and increased fracture risk, and circulating sex steroid levels have been shown to be associated both with bone mineral density and fracture risk in elderly men. However, in contrast to postmenopausal osteoporosis, the contribution of relatively small decrease of circulating sex steroid concentrations in the ageing male to the development of osteoporosis and related fractures, is probably only minor. In this review we provide several clinical and preclinical arguments in favor of a 'bone threshold' for occurrence of hypogonadal osteoporosis, corresponding to a grade of sex steroid deficiency that in general will not occur in many elderly men. Testosterone replacement therapy has been shown to increase bone mineral density in men, however data in osteoporotic ageing males are scarce, and evidence on fracture risk reduction is lacking. We conclude that testosterone replacement therapy should not be used as a sole bone-specific treatment in osteoporotic elderly men.

The non-modifiable factors age, gender, and genetics influence resistance exercise

Muscle mass and force are key for movement, life quality, and health. It is well established that resistance exercise is a potent anabolic stimulus increasing muscle mass and force. The response of a physiological system to resistance exercise is composed of non-modifiable (i.e., age, gender, genetics) and modifiable factors (i.e., exercise, nutrition, training status, etc.). Both factors are integrated by systemic responses (i.e., molecular signaling, genetic responses, protein metabolism, etc.), consequently resulting in functional and physiological adaptations. Herein, we discuss the influence of non-modifiable factors on resistance exercise: age, gender, and genetics. A solid understanding of the role of non-modifiable factors might help to adjust training regimes towards optimal muscle mass maintenance and health.

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.

Microsurgical Management of Male Infertility: Compelling Evidence That Collaboration with Qualified Male Reproductive Urologists Enhances Assisted Reproductive Technology (ART) Outcomes

A male factor plays a significant role in a couple's reproductive success. Today, advances in reproductive technology, such as intracytoplasmic sperm injection (ICSI), have allowed it to be possible for just a single sperm to fertilize an egg, thus, overcoming many of the traditional barriers to male fertility, such as a low sperm count, impaired motility, and abnormal morphology. Given these advances in reproductive technology, it has been questioned whether a reproductive urologist is needed for the evaluation and treatment of infertile and subfertile men. In this review, we aim to provide compelling evidence that collaboration between reproductive endocrinologists and reproductive urologists is essential for optimizing a couple's fertility outcomes, as well as for improving the health of infertile men and providing cost-effective care.

Transwoman Elite Athletes: Their Extra Percentage Relative to Female Physiology

There is increasing debate as to whether transwoman athletes should be included in the elite female competition. Most elite sports are divided into male and female divisions because of the greater athletic performance displayed by males. Without the sex division, females would have little chance of winning because males are faster, stronger, and have greater endurance capacity. Male physiology underpins their better athletic performance including increased muscle mass and strength, stronger bones, different skeletal structure, better adapted cardiorespiratory systems, and early developmental effects on brain networks that wires males to be inherently more competitive and aggressive. Testosterone secreted before birth, postnatally, and then after puberty is the major factor that drives these physiological sex differences, and as adults, testosterone levels are ten to fifteen times higher in males than females. The non-overlapping ranges of testosterone between the sexes has led sports regulators, such as the International Olympic Committee, to use 10 nmol/L testosterone as a sole physiological parameter to divide the male and female sporting divisions. Using testosterone levels as a basis for separating female and male elite athletes is arguably flawed. Male physiology cannot be reformatted by estrogen therapy in transwoman athletes because testosterone has driven permanent effects through early life exposure. This descriptive critical review discusses the inherent male physiological advantages that lead to superior athletic performance and then addresses how estrogen therapy fails to create a female-like physiology in the male. Ultimately, the former male physiology of transwoman athletes provides them with a physiological advantage over the cis-female athlete.

Testosterone supplementation and bone parameters: a systematic review and meta-analysis study

BACKGROUND

The role of testosterone (T) replacement therapy (TRT) in subjects with late onset hypogonadism is still the object of an intense debate.

METHODS

All observational studies and placebo-controlled or -uncontrolled randomized trials (RCTs) comparing the effect of TRT on different bone parameters were considered.

RESULTS

Out of 349 articles, 36 were considered, including 3103 individuals with a mean trial duration of 66.6 weeks. TRT improves areal bone mineral density (aBMD) at the spine and femoral neck levels in observational studies, whereas placebo-controlled RTCs showed a positive effect of TRT only at lumber spine and when trials included only hypogonadal patients at baseline (total testosterone < 12 nM). The effects on aBMD were more evident in subjects with lower T levels at baseline and increased as a function of trial duration and a higher prevalence of diabetic subjects. Either T or estradiol increase at endpoint contributed to aBMD improvement. TRT was associated with a significant reduction of bone resorption markers in observational but not in controlled studies.

CONCLUSION

TRT is able to inhibit bone resorption and increase bone mass, particularly at the lumbar spine level and when the duration is long enough to allow the anabolic effect of T and estrogens on bone metabolism to take place.

Testosterone therapy in children and adolescents: to whom, how, when?

Male production of testosterone is crucial for the development of a wide range of functions. External and internal genitalia formation, secondary sexual characteristics, spermatogenesis, growth velocity, bone mass density, psychosocial maturation, and metabolic and cardiovascular profiles are closely dependent on testosterone exposure. Disorders in androgen production can present during all life-stages, including childhood and adolescence, and testosterone therapy (TT) is in many cases the only treatment that can correct the underlying deficit. TT is controversial in the pediatric population as hypoandrogenism is difficult to classify and diagnose in these age groups, and standardized protocols of treatment and monitorization are still lacking. In pediatric patients, hypogonadism can be central, primary, or a combination of both. Testosterone preparations are typically designed for adults' TT, and providers need to be aware of the advantages and disadvantages of these formulations, especially cognizant of supratherapeutic dosing. Monitoring of testosterone levels in boys on TT should be tailored to the individual patient and based on the anticipated duration of therapy. Although clinical consensus is lacking, an approximation of the current challenges and common practices in pediatric hypoandrogenism could help elucidate the broad spectrum of pathologies that lie behind this single hormone deficiency with wide-ranging implications.

Effect of testosterone treatment on the trabecular bone score in older men with low serum testosterone

The trabecular bone score (TBS) is an indirect measure of vertebral bone microarchitecture. Our objective was to examine the effect of testosterone treatment on TBS. One hundred and ninety-seven hypogonadal men were randomized to testosterone or placebo. After 12 months, there was no difference in the changes in TBS by randomized group.

INTRODUCTION

In the Bone Trial of the Testosterone Trials, testosterone treatment increased trabecular volumetric bone mineral density (vBMD) and increased estimated bone strength as determined by finite element analysis. The trabecular bone score (TBS) is an indirect measure of vertebral bone microarchitecture. TBS predicts fracture independent of lumbar spine areal (a) BMD. The objective of this study was to examine the effect of testosterone treatment on TBS compared to its effects on vBMD and aBMD.

METHODS

Two hundred and eleven men were enrolled in the Bone Trial of the Testosterone Trials. Of these, 197 men had 2 repeat TBS and vBMD measurements; 105 men were allocated to receive testosterone, and 92 men to placebo for 1 year. TBS, aBMD, and vBMD were assessed at baseline and month 12.

RESULTS

There was no difference in the percent change in TBS by randomized group: 1.6% (95% confidence intervals (CI) 0.2-3.9) in the testosterone group and 1.4% (95% CI -0.2, 3.1) in the placebo group. In contrast, vBMD increased by 6% (95% CI 4.5-7.5) in the testosterone group compared to 0.4% (95% CI -1.65-0.88) in the placebo groups.

CONCLUSIONS

TBS is not clinically useful in monitoring the 1-year effect of testosterone treatment on bone structure in older hypogonadal men.

Hypogonadism in Adult Males with Prader-Willi Syndrome-Clinical Recommendations Based on a Dutch Cohort Study, Review of the Literature and an International Expert Panel Discussion

Prader-Willi syndrome (PWS) is a complex genetic syndrome characterized by hyperphagia, intellectual disability, hypotonia and hypothalamic dysfunction. Adults with PWS often have hormone deficiencies, hypogonadism being the most common. Untreated male hypogonadism can aggravate PWS-related health issues including muscle weakness, obesity, osteoporosis, and fatigue. Therefore, timely diagnosis and treatment of male hypogonadism is important. In this article, we share our experience with hypogonadism and its treatment in adult males with PWS and present a review of the literature. In order to report the prevalence and type of hypogonadism, treatment regimen and behavioral issues, we retrospectively collected data on medical interviews, physical examinations, biochemical measurements and testosterone replacement therapy (TRT) in 57 Dutch men with PWS. Fifty-six (98%) of the patients had either primary, central or combined hypogonadism. Untreated hypogonadism was associated with higher body mass index and lower hemoglobin concentrations. TRT was complicated by behavioral challenges in one third of the patients. Undertreatment was common and normal serum testosterone levels were achieved in only 30% of the patients. Based on the Dutch cohort data, review of the literature and an international expert panel discussion, we provide a practical algorithm for TRT in adult males with PWS in order to prevent undertreatment and related adverse health outcomes.

JATENZO®: Challenges in the development of oral testosterone

Testosterone therapy (TT) for the treatment of testosterone deficiency (TD) can be administered via several routes of administration. Due to a variety of concerns such as hepatotoxicity, an oral formulation has long been absent in the United States. Recently, JATENZO® (testosterone undecanoate) oral capsules was approved by the US FDA as an oral option for men suffering from TD. In this article, we will discuss the history and challenges in the development of a viable oral formulation of exogeneous TT and examine how JATENZO® addresses these concerns.

Hepatocyte Small Heterodimer Partner Mediates Sex-Specific Effects on Triglyceride Metabolism via Androgen Receptor in Male Mice

Mechanisms of sex differences in hypertriglyceridemia remain poorly understood. Small heterodimer partner (SHP) is a nuclear receptor that regulates bile acid, glucose, and lipid metabolism. SHP also regulates transcriptional activity of sex hormone receptors and may mediate sex differences in triglyceride (TG) metabolism. Here, we test the hypothesis that hepatic SHP mediates sex differences in TG metabolism using hepatocyte-specific SHP knockout mice. Plasma TGs in wild-type males were higher than in wild-type females and hepatic deletion of SHP lowered plasma TGs in males but not in females, suggesting hepatic SHP mediates plasma TG metabolism in a sex-specific manner. Additionally, hepatic deletion of SHP failed to lower plasma TGs in gonadectomized male mice or in males with knockdown of the liver androgen receptor, suggesting hepatic SHP modifies plasma TG via an androgen receptor pathway. Furthermore, the TG lowering effect of hepatic deletion of SHP was caused by increased clearance of postprandial TG and accompanied with decreased plasma levels of ApoC1, an inhibitor of lipoprotein lipase activity. These data support a role for hepatic SHP in mediating sex-specific effects on plasma TG metabolism through androgen receptor signaling. Understanding how hepatic SHP regulates TG clearance may lead to novel approaches to lower plasma TGs and mitigate cardiovascular disease risk.

Recent Update on the Molecular Mechanisms of Gonadal Steroids Action in Adipose Tissue

The gonadal steroids, including androgens, estrogens and progestogens, are involved in the control of body fat distribution in humans. Nevertheless, not only the size and localization of the fat depots depend on the sex steroids levels, but they can also highly affect the functioning of adipose tissue. Namely, the gonadocorticoids can directly influence insulin signaling, lipid metabolism, fatty acid uptake and adipokine production. They may also alter energy balance and glucose homeostasis in adipocytes in an indirect way, e.g., by changing the expression level of aquaglyceroporins. This work presents the recent advances in understanding the molecular mechanism of how the gonadal steroids influence the functioning of adipose tissue leading to a set of detrimental metabolic consequences. Special attention is given here to highlighting the sexual dimorphism of adipocyte functioning in terms of health and disease. Particularly, we discuss the molecular background of metabolic disturbances occurring in consequence of hormonal imbalance which is characteristic of some common endocrinopathies such as the polycystic ovary syndrome. From this perspective, we highlight the potential drug targets and the active substances which can be used in personalized sex-specific management of metabolic diseases, in accord with the patient's hormonal status.

Correlation Between Testosterone Replacement Treatment and Lower Urinary Tract Symptoms

Lower urinary tract symptoms (LUTS) are a cluster of voiding symptoms, such as weak stream, hesitancy, intermittency, urinary frequency, urgency, and nocturia. LUTS are frequent in elderly men and it considered the ultimate clinical symptoms of benign prostatic hyperplasia. With aging, male hypogonadism is increased which is defined as decreased ability of the testes to produce sperm and sex steroids because of a pituitary/hypothalamic, or testicular deficiency. In academic andrology associations, the term "male hypogonadism" is commonly used to categorize testosterone deficiency. Testosterone deficiency syndrome (TDS) is defined as a decrease in serum testosterone accompanied by symptoms such as libido decrease, depressive disorder, erectile dysfunction, and fatigue. Although the mechanism about testosterone-replacement therapy (TRT) effects on men with hypogonadism is not yet identified, TRT has been shown to effectively relieve the symptoms of TDS as well as LUTS by several studies. Although the present review demonstrates the effectiveness and safety of TRT in men with TDS by prior studies, future large scale of clinical trials should be conducted to present more high-quality evidence to clinicians and patients.

Heat Induces Oxidative Stress: Reproductive Organ Weights and Serum Metabolite Profile, Testes Structure, and Function Impairment in Male Cavy (Cavia porcellus)

The present study was designed to evaluate the effects of heat that induces oxidative stress on reproduction organ weight and serum biochemical, testes structure, and function in male guinea pig (Cavia porcellus). Forty-eight male guinea pigs with an average weight of 330.56 ± 23.62 g, aged 3–4 months, were distributed into four groups of 12 animals each. One group (control) was maintained to ambient temperature (20–25°C), while other groups (Groups 2–4) were exposed daily for 6 h, to 32 ± 1°C, 39±1°C, and 46 ± 1°C, respectively. All animals were sacrificed after 60 days' exposure and their reproductive characteristics values were determined. Results revealed a significant decrease (p < 0.05) of the weight of testes, epididymis, vas deferens, and accessory glands in cavies exposed to the highest temperature investigated (46 ± 1°C), compared to the control animals. There was a significant (p < 0.05) reduction of serum testosterone and LH levels in all heat stress-exposed groups (≥46 ± 1°C) when compared to the control group. Heat stress significantly (p < 0.05) decreased sperm mobility, sperm count, and testicular antioxidant enzymes, while increasing testicular malondialdehyde content. However, the serum level of HSP-40 increased in the animals exposed to 39 ± 1°C and decreased when the cavies were exposed to 46 ± 1°C. In conclusion, exposure to heat-induced oxidative stress results in impairment of reproduction organ weight and serum biochemical, testes structure, and function in male cavies.

Management of refractory ascites attenuates muscle mass reduction and improves survival in patients with decompensated cirrhosis

BACKGROUND

This study investigated time-course changes in skeletal muscle volume per year with tolvaptan in patients with refractory ascites that was unresponsive to loop diuretics and aldosterone antagonists.

METHODS

This retrospective study included 42 patients who received tolvaptan for refractory ascites and/or hepatic edema and underwent computed tomography (CT) before and ≥ 3 months after initiating tolvaptan. The time-course changes in skeletal muscle index per year [ΔSMI (%)] was calculated as follows: ΔSMI (%) = (SMI at final CT scan - SMI at initial CT scan)/SMI at initial CT scan × 100/years between CT scans.

RESULTS

Eligible patients were 23 men and 19 women of median age of 71 years (range 21-94 years). The median follow-up period was 22.7 (range 3.5-54.6) months. ΔSMI (%) was significantly higher in the responders group than in the nonresponder group. Multivariate analysis showed the response to tolvaptan was an independent and significant factor associated with an increase in muscle mass [odds ratio (OR) 20.364; 95% CI 2.327-178.97; P = 0.006]. Overall survival with tolvaptan was significantly higher in the responder group than in the nonresponder group. Multivariate analysis showed that the response to tolvaptan treatment was a significant contributor to good prognosis (OR 3.884; 95% CI 1.264-11.931; P = 0.018). A significant negative correlation was observed between the dosage of furosemide and ΔSMI (%) (P = 0.014).

CONCLUSIONS

Treatment of refractory ascites with tolvaptan may attenuate the progression of sarcopenia and improve the prognosis in patients with decompensated cirrhosis.

Hypogonadism, Type-2 Diabetes Mellitus, and Bone Health: A Narrative Review

One of the complications from chronic hyperglycemia and insulin resistance due to type 2 diabetes mellitus (T2DM) on the hypothalamic-pituitary-gonadal axis in men is the high prevalence of hypogonadotropic hypogonadism (HH). Both T2DM and hypogonadism are associated with impaired bone health and increased fracture risk but whether the combination results in even worse bone disease than either one alone is not well-studied. It is possible that having both conditions predisposes men to an even greater risk for fracture than either one alone. Given the common occurrence of HH or hypogonadism in general in T2DM, a significant number of men could be at risk. To date, there is very little information on the bone health men with both hypogonadism and T2DM. Insulin resistance, which is the primary defect in T2DM, is associated with low testosterone (T) levels in men and may play a role in the bidirectional relationship between these two conditions, which together may portend a worse outcome for bone. The present manuscript aims to review the available evidences on the effect of the combination of hypogonadism and T2DM on bone health and metabolic profile, highlights the possible metabolic role of the skeleton, and examines the pathways involved in the interplay between bone, insulin resistance, and gonadal steroids.

Testosterone replacement in young male cancer survivors: A 6-month double-blind randomised placebo-controlled trial

BACKGROUND

Young male cancer survivors have lower testosterone levels, higher fat mass, and worse quality of life (QoL) than age-matched healthy controls. Low testosterone in cancer survivors can be due to orchidectomy or effects of chemotherapy and radiotherapy. We have undertaken a double-blind, placebo-controlled, 6-month trial of testosterone replacement in young male cancer survivors with borderline low testosterone (7-12 nmol/l).

METHODS AND FINDINGS

This was a multicentre United Kingdom study conducted in secondary care hospital outpatients. Male survivors of testicular cancer, lymphoma, and leukaemia aged 25-50 years with morning total serum testosterone 7-12 nmol/l were recruited. A total of 136 men were randomised between July 2012 and February 2015 (42.6% aged 25-37 years, 57.4% 38-50 years, 88% testicular cancer, 10% lymphoma, matched for body mass index [BMI]). Participants were randomised 1:1 to receive testosterone (Tostran 2% gel) or placebo for 26 weeks. A dose titration was performed after 2 weeks. The coprimary end points were trunk fat mass and SF36 Physical Functioning score (SF36-PF) at 26 weeks by intention to treat. At 26 weeks, testosterone treatment compared with placebo was associated with decreased trunk fat mass (-0.9 kg, 95% CI -1.6 to -0.3, p = 0.0073), decreased whole-body fat mass (-1.8 kg, 95% CI -2.9 to -0.7, p = 0.0016), and increased lean body mass (1.5 kg, 95% CI 0.9-2.1, p < 0.001). Decrease in fat mass was greatest in those with a high truncal fat mass at baseline. There was no treatment effect on SF36-PF or any other QoL scores. Testosterone treatment was well tolerated. The limitations of our study were as follows: a relatively short duration of treatment, only three cancer groups included, and no hard end point data such as cardiovascular events.

CONCLUSIONS

In young male cancer survivors with low-normal morning total serum testosterone, replacement with testosterone is associated with an improvement in body composition.

TRIAL REGISTRATION

ISRCTN: 70274195, EudraCT: 2011-000677-31.

Sex hormones, aging and cardiometabolic syndrome

It is well documented that the metabolic syndrome predisposes patients to increased cardiovascular risk. Emerging data indicates that cardiovascular risk conferred by metabolic syndrome is highly dependent on sex and sex hormone status throughout the lifetime. Both male and female sex hormones, as well as sex chromosomes themselves, contribute to the development of obesity and intervene in the control of insulin homeostasis and blood pressure. Furthermore, men and women develop age-associated cardiometabolic risk in a sex-specific fashion in association with changes in these sex hormonal levels. Therefore, the current notion of the metabolic syndrome as a sex-independent diagnosis is antiquated, and novel studies and clinical trials utilizing these known sex differences in the development of metabolic dysregulation and cardiometabolic risk are warranted.

Testosterone and Dehydroepiandrosterone Treatment in Ageing Men: Are We All Set?

Although demographic statistics show that populations around the world are rapidly ageing, this rising life expectancy is accompanied by an increase in the number of people living with age-related chronic conditions, such as frailty, cognitive decline, depression, or sexual dysfunction. In men, a progressive decline in androgens occurs with increasing age, and low androgen levels are associated with age-related chronic conditions. However, androgen administration studies are inconclusive, showing differing results according to the androgen used (testosterone [T], dehydroepiandrosterone [DHEA]), the group of men examined (younger vs. older; eugonadal vs. hypogonadal) and the conditions studied (frailty, cognitive decline, depression, sexual dysfunction). In this review, the current state for the use of T and DHEA therapy in men for the age-related conditions is examined. Due to the progressive age-related decline in androgens leading to a higher rate of older men having low androgen levels, the effects of androgen treatment in elderly males will be of particular interest in this review. Dose-response relationships, the role of potential moderators, and the androgen treatment-related risk for adverse events will be discussed. Studies have suggested that T treatment - more so than DHEA treatment - may be an effective therapy against age-related chronic conditions in men with low T levels; especially older men. Such conditions include frailty, depression, or sexual dysfunction. However, T treatment does not emerge as an effective therapy against cognitive decline. Nevertheless, more high-quality, randomised controlled trials using T treatment for age-related chronic conditions are necessary if further conclusions are to be made.

Glucocorticoid-induced osteoporosis: 2019 concise clinical review

Glucocorticoids remain widely used for many medical conditions, and fractures are the most serious common adverse event related to long-term glucocorticoid use. Glucocorticoid-induced osteoporosis (GIOP) develops in a time- and dose-dependent manner, but even at low doses, an increased risk of fragility fracture may be observed even within the first month of treatment. GIOP is mediated by multiple pathophysiologic mechanisms resulting in an inhibition of bone formation and an increase in bone resorption. The clinical assessment of GIOP has potential pitfalls since dual-energy X-ray absorptiometry (DXA) may underestimate the risk of fracture in patients treated with glucocorticoids. Many national organizations have developed guidelines for assessing fracture risk and treating patients with, or at risk for, GIOP. These groups advocate both antiresorptive agents and bone-forming agents based predominately on their efficacy in improving bone mineral density. Oral bisphosphonates are generally the first-line therapy for GIOP in most patients due to their proven efficacy, good safety, and low cost. For those patients at greater risk of fracture, teriparatide should be considered earlier, based on its ability to significantly reduce vertebral fractures when compared with alendronate. GIOP remains a major public health concern that is at least partially preventable with current and potential future therapeutic options.

Obesity and Hypogonadism-A Narrative Review Highlighting the Need for High-Quality Data in Adolescents

The prevalence of obesity continues to rise in adult and pediatric populations throughout the world. Obesity has a direct impact on all organ systems, including the reproductive system. This review summarizes current knowledge about the effects of obesity on the male reproductive system across age, highlighting the need for more data in children and adolescents. Male hypogonadism is commonly seen in patients with obesity and affects the onset, duration, and progression of puberty. Different pathophysiologic mechanisms include increased peripheral conversion of testosterone to estrone and increased inflammation due to increased fat, both of which lead to suppression of the hypothalamic-pituitary-gonadotropin (HPG) axis and delayed development of secondary sexual characteristics in adolescent males. Evaluation of the HPG axis in obesity includes a thorough history to exclude other causes of hypogonadism and syndromic associations. Evaluation should also include investigating the complications of low testosterone, including increased visceral fat, decreased bone density, cardiovascular disease risk, and impaired mood and cognition, among others. The mainstay of treatment is weight reduction, but medications such as testosterone and clomiphene citrate used in adults, remain scarcely used in adolescents. Male hypogonadism associated with obesity is common and providers who care for adolescents and young adults with obesity should be aware of its impact and management.

Testosterone Replacement in Men with Age-Related Low Testosterone: What Did We Learn From The Testosterone Trials?

The T Trials were a coordinated set of seven double-blind, placebo-controlled trials to assess efficacy and safety of testosterone versus placebo gel treatment for one year in 788 older men 65 years or older with hypogonadism who had self-reported and objective impairment of sexual and physical function and/or vitality and an average of two morning serum testosterone concentrations < 275 ng/dL. Testosterone dose was adjusted to the mid-normal range for young men. Compared to placebo, testosterone treatment moderately improved sexual function, hemoglobin concentration and corrected anemia, and slightly improved walking distance, vitality, mood and depressive symptoms and bone density and strength, but did not improve cognitive function. Testosterone treatment slightly increased non-calcified and total plaque volume; while concerning, the clinical significance of this finding is not clear. Testosterone treatment also increased PSA levels and referral for urological evaluation, and caused erythrocytosis in some men. The T Trials provided definitive evidence for short-term clinically meaningful, albeit modest benefits and risks of testosterone treatment in older men with unequivocal age-related hypogonadism. Larger and longer-term placebo-controlled clinical trials are needed to assess the long-term benefits and risks of testosterone treatment on clinical outcomes such as frailty, depression, fractures, prostate cancer and cardiovascular events.

Effect of Testosterone Use on Bone Mineral Density in HIV-Infected Men

HIV-infected men have increased rates of osteoporosis and fracture compared to HIV-uninfected men. Testosterone use among HIV-infected men is common. In HIV-uninfected men, testosterone increases bone mineral density (BMD), but its effects have not been evaluated in HIV-infected men. In a substudy of Multicenter AIDS Cohort Study (MACS), the Bone Strength Substudy (BOSS) enrolled 202 HIV-infected and 201 HIV-uninfected men aged between 50 and 69 years. Study participants underwent dual-energy X-ray absorptiometry (DXA) at the lumbar spine (LS), total hip (TH), and femoral neck (FN) and detailed assessment of osteoporosis risk factors. We used multivariable linear regression to determine associations and 95% confidence intervals (CIs) between self-reported testosterone use and T-scores at the LS, TH, and FN after adjustment for demographics, behavioral covariates, comorbidities, and other traditional osteoporosis risk factors. HIV-infected men reported more frequent testosterone use (22% vs. 4%; p < .001) and had lower median BMD T-score at TH than HIV-uninfected men (0.0 vs. 0.3; p = .045) but similar T-scores at LS and FN. In the overall study population, testosterone use was associated with significantly greater BMD T-score at LS (0.68; 95% CI: 0.22-1.13). In HIV-infected men with virologic suppression, testosterone was significantly associated with higher BMD T-score at LS (0.95; 95% CI: 0.36-1.54) and TH (0.45; 95% CI: 0.04-0.86). Current testosterone use is common in HIV-infected men and was associated with higher BMD, compared to those not taking testosterone. Testosterone's role in reducing fracture risk in HIV-infected men should be investigated.

Metabolic Disorders and Male Hypogonadotropic Hypogonadism

Several studies highlight that testosterone deficiency is associated with, and predicts, an increased risk of developing metabolic disorders, and, on the other hand, is highly prevalent in obesity, metabolic syndrome and type-2 diabetes mellitus. Models of gonadotropin releasing hormone deficiency, and androgen deprivation therapy in patients with prostate cancer, suggest that hypogonadotropic hypogonadism might contribute to the onset or worsening of metabolic conditions, by increasing visceral adiposity and insulin resistance. Nevertheless, in functional hypogonadism, as well as in late onset hypogonadism, the relationship between hypogonadotropic hypogonadism and metabolic disorders is bidirectional, and a vicious circle between the two components has been documented. The mechanisms underlying the crosstalk between testosterone deficiency and metabolic disorders include increased visceral adipose tissue and insulin resistance, leading to development of metabolic disorders, which in turn contribute to a further reduction of testosterone levels. The decrease in testosterone levels might be determined by insulin resistance-mediated and, possibly, pro-inflammatory cytokine-mediated decrease of sex hormone binding globulin, resulting in a temporary increased free testosterone available for aromatization to estradiol in visceral adipose tissue, followed by a subsequent decrease in free testosterone levels, due to the excess of visceral adipose tissue and aromatization; by a direct inhibitory effect of increased leptin levels on Leydig cells; and by a reduced gonadotropin secretion induced by estradiol, inflammatory mediators, leptin resistance, and insulin resistance, with the ultimate determination of a substantial hypogonadotropic hypogonadism. The majority of studies focusing on the effects of testosterone replacement therapy on metabolic profile reported a beneficial effect of testosterone on body weight, waist circumference, body mass index, body composition, cholesterol levels, and glycemic control. Consistently, several interventional studies demonstrated that correction of metabolic disorders, in particular with compounds displaying a greater impact on body weight and insulin resistance, improved testosterone levels. The aim of the current review is to provide a comprehensive overview on the relationship between hypogonadotropic hypogonadism and metabolism, by clarifying the independent role of testosterone deficiency in the pathogenesis of metabolic disorders, and by describing the relative role of testosterone deficiency and metabolic impairment, in the context of the bidirectional relationship between hypogonadism and metabolic diseases documented in functional hypogonadotropic hypogonadism. These aspects will be assessed by describing metabolic profile in men with hypogonadotropic hypogonadism, and androgenic status in men with metabolic disorders; afterwards, the reciprocal effects of testosterone replacement therapy and corrective interventions on metabolic derangements will be reported.

Sex Differences in Presentation but Not in Outcome for ACTH-Dependent Cushing's Syndrome

Background: Sex differences in clinical picture of ACTH-dependent Cushing's syndrome are controversial, except for the known higher prevalence in females. We compared a broad range of potential differences to enable a more accurate understanding of the clinical picture of sex-specific ACTH-dependent Cushing's syndrome. Methods: Cohort study including consecutive patients with ACTH-dependent Cushing's syndrome from Leiden and Berlin diagnosed between 2000 and 2016. We compared clinical presentation, biochemical parameters, diagnostic tests, surgical outcome, and comorbidities between men and women. Results: We included 130 patients: 37 males and 93 females. With similar cortisol concentrations, ACTH concentrations were higher in males than females at time of diagnosis (median: 116 vs. 57 ng/L). The prevalence of osteoporosis was higher in males than in females (48.6 vs. 25.0%), persisting after surgery, with more vertebral fractures (16.2 vs. 5.4%) before surgery. Males showed more anemia (75.9 vs. 36.8%) after surgery. There were no differences in etiology, pituitary tumor size, diagnostic and therapeutic strategy, or surgical outcome between sexes. Conclusions: Based on this study, males and females with ACTH-dependent Cushing's syndrome present different clinical patterns. However, these differences do not justify different diagnostic strategies or treatment based on sex, considering the similar surgical outcome. Clinicians should be alert to diagnose accompanying osteoporosis (with fractures) in male patients with ACTH-dependent Cushing's syndrome.

Body composition changes with testosterone replacement therapy following spinal cord injury and aging: A mini review

Context Hypogonadism is a male clinical condition in which the body does not produce enough testosterone. Testosterone plays a key role in maintaining body composition, bone mineral density, sexual function, mood, erythropoiesis, cognition and quality of life. Hypogonadism can occur due to several underlying pathologies during aging and in men with physical disabilities, such as spinal cord injury (SCI). This condition is often under diagnosed and as a result, symptoms undertreated. Methods In this mini-review, we propose that testosterone replacement therapy (TRT) may be a viable strategy to improve lean body mass (LBM) and fat mass (FM) in men with SCI. Evidence Synthesis Supplementing the limited data from SCI cohorts with consistent findings from studies in non-disabled aging men, we present evidence that, relative to placebo, transdermal TRT can increase LBM and reduce FM over 3-36 months. The impact of TRT on bone mineral density and metabolism is also discussed, with particular relevance for persons with SCI. Moreover, the risks of TRT remain controversial and pertinent safety considerations related to transdermal administration are outlined. Conclusion Further research is necessary to help develop clinical guidelines for the specific dose and duration of TRT in persons with SCI. Therefore, we call for more high-quality randomized controlled trials to examine the efficacy and safety of TRT in this population, which experiences an increased risk of cardiometabolic diseases as a result of deleterious body composition changes after injury.

Circulating Testosterone as the Hormonal Basis of Sex Differences in Athletic Performance

Elite athletic competitions have separate male and female events due to men's physical advantages in strength, speed, and endurance so that a protected female category with objective entry criteria is required. Prior to puberty, there is no sex difference in circulating testosterone concentrations or athletic performance, but from puberty onward a clear sex difference in athletic performance emerges as circulating testosterone concentrations rise in men because testes produce 30 times more testosterone than before puberty with circulating testosterone exceeding 15-fold that of women at any age. There is a wide sex difference in circulating testosterone concentrations and a reproducible dose-response relationship between circulating testosterone and muscle mass and strength as well as circulating hemoglobin in both men and women. These dichotomies largely account for the sex differences in muscle mass and strength and circulating hemoglobin levels that result in at least an 8% to 12% ergogenic advantage in men. Suppression of elevated circulating testosterone of hyperandrogenic athletes results in negative effects on performance, which are reversed when suppression ceases. Based on the nonoverlapping, bimodal distribution of circulating testosterone concentration (measured by liquid chromatography-mass spectrometry)-and making an allowance for women with mild hyperandrogenism, notably women with polycystic ovary syndrome (who are overrepresented in elite athletics)-the appropriate eligibility criterion for female athletic events should be a circulating testosterone of <5.0 nmol/L. This would include all women other than those with untreated hyperandrogenic disorders of sexual development and noncompliant male-to-female transgender as well as testosterone-treated female-to-male transgender or androgen dopers.

Lessons From the Testosterone Trials

The Testosterone Trials (TTrials) were a coordinated set of seven placebo-controlled, double-blind trials in 788 men with a mean age of 72 years to determine the efficacy of increasing the testosterone levels of older men with low testosterone. Testosterone treatment increased the median testosterone level from unequivocally low at baseline to midnormal for young men after 3 months and maintained that level until month 12. In the Sexual Function Trial, testosterone increased sexual activity, sexual desire, and erectile function. In the Physical Function Trial, testosterone did not increase the distance walked in 6 minutes in men whose walk speed was slow; however, in all TTrial participants, testosterone did increase the distance walked. In the Vitality Trial, testosterone did not increase energy but slightly improved mood and depressive symptoms. In the Cognitive Function Trial, testosterone did not improve cognitive function. In the Anemia Trial, testosterone increased hemoglobin in both men who had anemia of a known cause and in men with unexplained anemia. In the Bone Trial, testosterone increased volumetric bone mineral density and the estimated strength of the spine and hip. In the Cardiovascular Trial, testosterone increased the coronary artery noncalcified plaque volume as assessed using computed tomographic angiography. Although testosterone was not associated with more cardiovascular or prostate adverse events than placebo, a trial of a much larger number of men for a much longer period would be necessary to determine whether testosterone increases cardiovascular or prostate risk.

Therapist-Assisted Progressive Resistance Training, Protein Supplements, and Testosterone Injections in Frail Older Men with Testosterone Deficiency: Protocol for a Randomized Placebo-Controlled Trial

BACKGROUND

Fall accidents are a major cause of mortality among the elderly and the leading cause of traumatic brain injury. After a fall, many elderly people never completely recover and need help in coping with everyday life. Due to the increasing older population in the world, injuries, disabilities, and deaths caused by falls are a growing worldwide problem. Muscle weakness leads to greatly increased risk of falling, decreased quality of life, and decline in functional capacity. Muscle mass and muscle power decrease about 40% from age 20 to 80 years, and the level of testosterone decreases with age and leads to impaired muscle mass. In addition, 20% of men older than 60 years-and 50% older than 80 years-have low levels of testosterone. Treatments after a fall are significant financial burdens on health and social care, and it is important to find treatments that can enhance function in the elderly people.

OBJECTIVE

The purpose of this study is to investigate whether testosterone and progressive resistance training alone or combined can improve muscle strength and reduce the risk of falls in older men. Additionally, we will examine whether such treatments can improve quality of life, functional capacity, including sexual function, and counteract depression.

METHODS

This is a randomized placebo-controlled, double-blind trial in which frail older men with testosterone deficiency are treated with testosterone supplemental therapy and therapist-assisted progressive resistance training for 20 weeks, with the possibility to continue treatment for 1 year. Four study arms of 48 participants each are provided based on factorial assignment to testosterone supplemental therapy and progressive resistance training. The 4 groups are as follows: controls given placebo injections without physical exercise for 20 weeks, testosterone-alone group given testosterone injections without physical exercise for 20 weeks, training-alone group given placebo injections for 20 weeks combined with 16 weeks of progressive strength training, and combination group given testosterone injections for 20 weeks combined with 16 weeks of progressive strength training. Performance in the 30-second chair stand test to measure improvement of general strength, balance, and power in lower extremities is the primary endpoint. Secondary endpoints comprising tests of cognition, muscle strength, and quality of life are applied before and after the training.

RESULTS

Funding was provided in October 2016. Results are expected to be available in 2020. Sample size was calculated to 152 participants divided into 4 equal-sized groups. Due to age, difficulty in transport, and the time-consuming intervention, up to 25% dropouts are expected; thus, we aim to include at least 192 participants.

CONCLUSIONS

This investigation will evaluate the efficacy of testosterone supplemental therapy alone or combined with progressive resistance training. Additionally, improvements in quality of life and cognition are explored.

TRIAL REGISTRATION

Clinicaltrials.gov NCT02873559; https://clinicaltrials.gov/ct2/show/NCT02873559 (Archived by WebCite at http://www.webcitation.org/6x0BhU2p3).

Trials of testosterone replacement reporting cardiovascular adverse events

The numbers of testosterone prescriptions written have increased several-fold worldwide, but the incidence of pathological hypogonadism due to hypothalamic, pituitary, and testicular disease has remained unchanged. Most of these prescriptions are being dispensed to middle-aged and older men who have experienced age-related decline in serum testosterone levels; a subset of the population in which benefits of testosterone replacement is at best, modest. Recently, some randomized controlled trials have reported increased cardiovascular events in men (mainly older men and those with prevalent cardiovascular disease) with testosterone use, and a few recent meta-analyses have confirmed these findings. In this review, we discuss trials of testosterone therapy that have reported higher cardiovascular events, relevant trials that have not reported increased cardiovascular events and large trials that have focused on cardiovascular risk (mainly atherosclerosis progression) as their main outcome. We also review findings from meta-analyses that have evaluated cardiovascular events in various testosterone trials. Finally, we discuss some potential mechanisms by which testosterone use might result in an increased cardiovascular risk. As none of the trials conducted to date were adequately powered to evaluate cardiovascular events, no firm conclusions can be drawn regarding the cardiovascular safety of testosterone therapy at this time. In the interim, we hope that this review will help practitioners make informed decisions regarding the care of their patients.

Episode-like pulse testosterone supplementation induces tumor senescence and growth arrest down-modulating androgen receptor through modulation of p-ERK1/2, pARser81 and CDK1 signaling: biological implications for men treated with testosterone replacement therapy

Despite the growing body of knowledge showing that testosterone (T) may not significantly affect tumor progression in hypogonadal patients treated for prostate cancer (Pca), the use of this hormone in this population still remains controversial. The effects of continuous or pulsed T stimulation were tested in vitro and in vivo on androgen-sensitive Pca cell lines in order to assess the differential biological properties of these two treatment modalities. Pulsed T treatment resulted in a greater inhibition than continuous T supplementation of tumor growth in vitro and in vivo. The effects of pulsed T treatment on tumor growth inhibition, G0/G1 cell cycle arrest, and tumor senescence was more pronounced than those obtained upon continuous T treatments. Mechanistic studies revealed that G0/G1 arrest and tumor senescence upon pulsed T treatment were associated with a marked decrease in cyclin D1, c-Myc and SKp2, CDK4 and p-Rb levels and upregulation of p27 and p-ERK1/2. Pulsed, but not continuous, T supplementation decreased the expression levels of AR, p-AR^ser81 and CDK1 in both cellular models. The in vitro results were confirmed in an in vivo xenografts, providing evidence of a greater inhibitory activity of pulsed supraphysiological T supplementation than continuous treatment, both in terms of tumor volume and decreased AR, p-AR^ser81, PSA and CDK1 staining. The rapid cycling from hypogonadal to physiological or supra-physiological T intraprostatic concentrations results in cytostatic and senescence effects in preclinical models of androgen-sensitive Pca. Our preclinical evidence provides relevant new insights in the biology of Pca response to pulsed T supplementation.

A randomized double-blind study of testosterone replacement therapy or placebo in testicular cancer survivors with mild Leydig cell insufficiency (Einstein-intervention)

BACKGROUND

Elevated serum levels of luteinizing hormone and slightly decreased serum levels of testosterone (mild Leydig cell insufficiency) is a common hormonal disturbance in testicular cancer (TC) survivors. A number of studies have shown that low serum levels of testosterone is associated with low grade inflammation and increased risk of metabolic syndrome. However, so far, no studies have evaluated whether testosterone substitution improves metabolic dysfunction in TC survivors with mild Leydig cell insufficiency.

METHODS/DESIGN

This is a single-center, randomized, double-blind, placebo-controlled study, designed to evaluate the effect of testosterone replacement therapy in TC survivors with mild Leydig cell insufficiency. Seventy subjects will be randomized to receive either testosterone replacement therapy or placebo. The subjects will be invited for an information meeting where informed consent will be obtained. Afterwards, a 52-weeks treatment period begins in which study participants will receive a daily dose of transdermal testosterone or placebo. Dose adjustment will be made three times during the initial 8 weeks of the study to a maximal daily dose of 40 mg of testosterone in the intervention arm. Evaluation of primary and secondary endpoints will be performed at baseline, 26 weeks post-randomization, at the end of treatment (52 weeks) and 3 months after completion of treatment (week 64).

DISCUSSION

This study is the first to investigate the effect of testosterone substitution in testicular cancer survivors with mild Leydig cell insufficiency. If positive, it may change the clinical handling of testicular cancer survivors with borderline low levels of testosterone.

TRIAL REGISTRATION

ClinicalTrials.gov : NCT02991209 (November 25, 2016).

Testosterone deficiency in adults and corresponding treatment patterns across the globe

The global prevalence of testosterone deficiency (TD) ranges from 10–40%. The actual diagnosis of TD is controversial, as a wide range of total testosterone (TT) thresholds are used for diagnosis (200–400 ng/dL), and physicians differ in their emphasis placed on clinical symptoms. There are also significant global differences in the prescription patterns of testosterone replacement therapy (TRT). In the United States, prescription of TRT is significantly higher than the rest of the world, increasing 3-fold over the last 10 years and more so in eugonadal men. The majority of treating physicians emphasizes clinical symptomology of TD over laboratory values, and up to one-fourth of their patients do not even have serum testosterone levels. There are significant inter-physician differences in willingness to prescribe TRT in the setting of prostate cancer. Data is scarce on testosterone prescribing patterns in Africa, Asia, and the Middle East. More literature is needed to better characterize how physicians from different regions diagnose TD.

Effect of Testosterone Treatment on Volumetric Bone Density and Strength in Older Men With Low Testosterone: A Controlled Clinical Trial

IMPORTANCE

As men age, they experience decreased serum testosterone concentrations, decreased bone mineral density (BMD), and increased risk of fracture.

OBJECTIVE

To determine whether testosterone treatment of older men with low testosterone increases volumetric BMD (vBMD) and estimated bone strength.

DESIGN, SETTING, AND PARTICIPANTS

Placebo-controlled, double-blind trial with treatment allocation by minimization at 9 US academic medical centers of men 65 years or older with 2 testosterone concentrations averaging less than 275 ng/L participating in the Testosterone Trials from December 2011 to June 2014. The analysis was a modified intent-to-treat comparison of treatment groups by multivariable linear regression adjusted for balancing factors as required by minimization.

INTERVENTIONS

Testosterone gel, adjusted to maintain the testosterone level within the normal range for young men, or placebo gel for 1 year.

MAIN OUTCOMES AND MEASURES

Spine and hip vBMD was determined by quantitative computed tomography at baseline and 12 months. Bone strength was estimated by finite element analysis of quantitative computed tomography data. Areal BMD was assessed by dual energy x-ray absorptiometry at baseline and 12 months.

RESULTS

There were 211 participants (mean [SD] age, 72.3 [5.9] years; 86% white; mean [SD] body mass index, 31.2 [3.4]). Testosterone treatment was associated with significantly greater increases than placebo in mean spine trabecular vBMD (7.5%; 95% CI, 4.8% to 10.3% vs 0.8%; 95% CI, -1.9% to 3.4%; treatment effect, 6.8%; 95% CI, 4.8%-8.7%; P < .001), spine peripheral vBMD, hip trabecular and peripheral vBMD, and mean estimated strength of spine trabecular bone (10.8%; 95% CI, 7.4% to 14.3% vs 2.4%; 95% CI, -1.0% to 5.7%; treatment effect, 8.5%; 95% CI, 6.0%-10.9%; P < .001), spine peripheral bone, and hip trabecular and peripheral bone. The estimated strength increases were greater in trabecular than peripheral bone and greater in the spine than hip. Testosterone treatment increased spine areal BMD but less than vBMD.

CONCLUSIONS AND RELEVANCE

Testosterone treatment for 1 year of older men with low testosterone significantly increased vBMD and estimated bone strength, more in trabecular than peripheral bone and more in the spine than hip. A larger, longer trial could determine whether this treatment also reduces fracture risk.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00799617.

Association of Testosterone Levels With Anemia in Older Men: A Controlled Clinical Trial

IMPORTANCE

In one-third of older men with anemia, no recognized cause can be found.

OBJECTIVE

To determine if testosterone treatment of men 65 years or older with unequivocally low testosterone levels and unexplained anemia would increase their hemoglobin concentration.

DESIGN, SETTING, AND PARTICIPANTS

A double-blinded, placebo-controlled trial with treatment allocation by minimization using 788 men 65 years or older who have average testosterone levels of less than 275 ng/dL. Of 788 participants, 126 were anemic (hemoglobin ≤12.7 g/dL), 62 of whom had no known cause. The trial was conducted in 12 academic medical centers in the United States from June 2010 to June 2014.

INTERVENTIONS

Testosterone gel, the dose adjusted to maintain the testosterone levels normal for young men, or placebo gel for 12 months.

MAIN OUTCOMES AND MEASURES

The percent of men with unexplained anemia whose hemoglobin levels increased by 1.0 g/dL or more in response to testosterone compared with placebo. The statistical analysis was intent-to-treat by a logistic mixed effects model adjusted for balancing factors.

RESULTS

The men had a mean age of 74.8 years and body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared) of 30.7; 84.9% were white. Testosterone treatment resulted in a greater percentage of men with unexplained anemia whose month 12 hemoglobin levels had increased by 1.0 g/dL or more over baseline (54%) than did placebo (15%) (adjusted OR, 31.5; 95% CI, 3.7-277.8; P = .002) and a greater percentage of men who at month 12 were no longer anemic (58.3%) compared with placebo (22.2%) (adjusted OR, 17.0; 95% CI, 2.8-104.0; P = .002). Testosterone treatment also resulted in a greater percentage of men with anemia of known cause whose month 12 hemoglobin levels had increased by 1.0 g/dL or more (52%) than did placebo (19%) (adjusted OR, 8.2; 95% CI, 2.1-31.9; P = .003). Testosterone treatment resulted in a hemoglobin concentration of more than 17.5 g/dL in 6 men who had not been anemic at baseline.

CONCLUSIONS AND RELEVANCE

Among older men with low testosterone levels, testosterone treatment significantly increased the hemoglobin levels of those with unexplained anemia as well as those with anemia from known causes. These increases may be of clinical value, as suggested by the magnitude of the changes and the correction of anemia in most men, but the overall health benefits remain to be established. Measurement of testosterone levels might be considered in men 65 years or older who have unexplained anemia and symptoms of low testosterone levels.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00799617.

Effect of Testosterone Treatment on Adipokines and Gut Hormones in Obese Men on a Hypocaloric Diet

Context

In obese men with lowered testosterone levels, testosterone treatment augments diet-associated loss of body fat.

Objective

We hypothesized that testosterone treatment modulates circulating concentrations of hormonal mediators of fat mass and energy homeostasis in obese men undergoing a weight loss program.

Design

Prespecified secondary analysis of a randomized, double-blind, placebo-controlled trial.

Setting

Tertiary referral center.

Participants

Obese men (body mass index ≥30 kg/m²) with a repeated total testosterone level ≤12 nmol/L.

Intervention

One hundred participants mean age 53 years (interquartile range 47 to 60 years) receiving 10 weeks of a very low-energy diet followed by 46 weeks of weight maintenance were randomly assigned at baseline to 56 weeks of intramuscular testosterone undecanoate (cases, n = 49) or matching placebo (controls, n = 51). Eighty-two men completed the study.

Main outcomes

Between-group differences in leptin, adiponectin, ghrelin, glucagon like peptide-1, gastric inhibitory polypeptide, peptide YY, pancreatic polypeptide, and amylin levels.

Results

At study end, compared with controls, cases had greater reductions in leptin [mean adjusted difference (MAD), -3.6 ng/mL (95% CI, -5.3 to -1.9); P < 0.001]. The change in leptin levels between cases and controls was dependent on baseline fat mass, as the between-group difference progressively increased with increasing fat mass [MAD, -0.26 ng/mL (95% CI, -0.31 to -0.26); P = 0.001 per 1 kg of baseline fat mass]. Weight loss-associated changes in other hormones persisted during the weight maintenance phase but were not modified by testosterone treatment.

Conclusions

Testosterone treatment led to reductions in leptin beyond those achieved by diet-associated weight loss. Testosterone treatment may reduce leptin resistance in obese men.

Combined Effects of Androgen and Growth Hormone on Osteoblast Marker Expression in Mouse C2C12 and MC3T3-E1 Cells Induced by Bone Morphogenetic Protein

Osteoblasts undergo differentiation in response to various factors, including growth factors and steroids. Bone mass is diminished in androgen- and/or growth hormone (GH)-deficient patients. However the functional relationship between androgen and GH, and their combined effects on bone metabolism, remains unclear. Here we investigated the mutual effects of androgen and GH on osteoblastic marker expression using mouse myoblastic C2C12 and osteoblast-like MC3T3-E1 cells. Combined treatment with dihydrotestosterone (DHT) and GH enhanced BMP-2-induced expression of Runx2, ALP, and osteocalcin mRNA, compared with the individual treatments in C2C12 cells. Co-treatment with DHT and GH activated Smad1/5/8 phosphorylation, Id-1 transcription, and ALP activity induced by BMP-2 in C2C12 cells but not in MC3T3-E1 cells. The insulin-like growth factor (IGF-I) mRNA level was amplified by GH and BMP-2 treatment and was restored by co-treatment with DHT in C2C12 cells. The mRNA level of the IGF-I receptor was not significantly altered by GH or DHT, while it was increased by IGF-I. In addition, IGF-I treatment increased collagen-1 mRNA expression, whereas blockage of endogenous IGF-I activity using an anti-IGF-I antibody failed to suppress the effect of GH and DHT on BMP-2-induced Runx2 expression in C2C12 cells, suggesting that endogenous IGF-I was not substantially involved in the underlying GH actions. On the other hand, androgen receptor and GH receptor mRNA expression was suppressed by BMP-2 in both cell lines, implying the existence of a feedback action. Collectively the results showed that the combined effects of androgen and GH facilitated BMP-2-induced osteoblast differentiation at an early stage by upregulating BMP receptor signaling.

Testosterone replacement therapy and voiding dysfunction

Testosterone replacement therapy (TRT) represents an increasing popular treatment option for men with late-onset hypogonadism (LOH). Because of unsubstantiated beliefs of testosterone’s effect on the prostate, the FDA has recently placed a warning on testosterone products, stating that TRT may worsen benign prostatic hyperplasia (BPH). Within this review article we have demonstrated the current understanding of the physiology of testosterone and its relationship with prostatic and lower urinary tract physiology. The current evidence suggests that not only does TRT not worsen lower urinary tract symptoms (LUTS), but that hypogonadism itself is an important risk factor for LUTS/BPH.

Effects of long-term androgen replacement therapy on the physical and mental statuses of aging males with late-onset hypogonadism: a multicenter randomized controlled trial in Japan (EARTH Study)

Androgen replacement therapy (ART) efficacy on late-onset hypogonadism (LOH) has been widely investigated in Western countries; however, it remains controversial whether ART can improve health and prolong active lifestyles. We prospectively assessed long-term ART effects on the physical and mental statuses of aging men with LOH in Japan. The primary endpoint was health-related quality of life assessed by questionnaires. Secondary endpoints included glycemic control, lipid parameters, blood pressure, waist circumference, body composition, muscular strength, International Prostate Symptom Scores (IPSS), International Index of Erectile Function-5 (IIEF-5) scores, and serum prostate-specific antigen levels. Of the 1637 eligible volunteers, 334 patients > 40 years with LOH were randomly assigned to either the ART (n = 169) or control groups (n = 165). Fifty-two weeks after the initial treatment, ART significantly affected the role physical subdomain of the short form-36 health survey (SF-36) scale (P = 0.0318). ART was also associated with significant decreases in waist circumstance (P = 0.002) and serum triglyceride (TG) (P = 0.013) and with significant increases in whole-body and leg muscle mass volumes (P = 0.071 and 0.0108, respectively), serum hemoglobin (P < 0.001), IPSS voiding subscore (P = 0.0418), and the second question on IIEF-5 (P = 0.0049). There was no significant difference between the groups in terms of severe adverse events. In conclusion, in patients with LOH, long-term ART exerted beneficial effects on Role Physical subdomain of the SF-36 scale, serum TG, waist circumstance, muscle mass volume, voiding subscore of IPSS, and the second question of IIEF-5. We hope our study will contribute to the future development of this area.

Testosterone Treatment and Sexual Function in Older Men With Low Testosterone Levels

CONTEXT

The Testosterone Trials are a coordinated set of seven trials to determine the efficacy of T in symptomatic men ≥65 years old with unequivocally low T levels. Initial results of the Sexual Function Trial showed that T improved sexual activity, sexual desire, and erectile function.

OBJECTIVE

To assess the responsiveness of specific sexual activities to T treatment; to relate hormone changes to changes in sexual function; and to determine predictive baseline characteristics and T threshold for sexual outcomes.

DESIGN

A placebo-controlled trial.

SETTING

Twelve academic medical centers in the United States.

PARTICIPANTS

A total of 470 men ≥65 years of age with low libido, average T <275 ng/dL, and a partner willing to have sexual intercourse at least twice a month.

METHODS

Men were assigned to take T gel or placebo for 1 year. Sexual function was assessed by three questionnaires every 3 months: the Psychosexual Daily Questionnaire, the Derogatis Interview for Sexual Function, and the International Index of Erectile Function.

RESULTS

Compared with placebo, T administration significantly improved 10 of 12 measures of sexual activity. Incremental increases in total and free T and estradiol levels were associated with improvements in sexual activity and desire, but not erectile function. No threshold T level was observed for any outcome, and none of the 27 baseline characteristics predicted responsiveness to T.

CONCLUSIONS

In older men with low libido and low T levels, improvements in sexual desire and activity in response to T treatment were related to the magnitude of increases in T and estradiol levels, but there was no clear evidence of a threshold effect.

Effects of Transdermal Testosterone Gel or an Aromatase Inhibitor on Prostate Volume in Older Men

CONTEXT

T replacement is being increasingly offered to older men with age-related low T; hence, monitoring prostate health is important during T therapy. Data suggest that estrogens have an independent effect on the prostate and some effects of T on the prostate might be mediated via its aromatization to estradiol. Although some studies have assessed the effects of T replacement on prostate volume, the differential effects of T and estradiol have not been delineated.

OBJECTIVE

The objective of the study was to investigate the relative effects of T and estradiol on prostate volume in older men with low T.

PARTICIPANTS

Thirty-one men, 65 years old or older with total T less than 350 ng/dL (measured by mass spectrometry) participated in the study.

INTERVENTION

The intervention included randomization to 5 g transdermal T gel (TT), 1 mg oral aromatase inhibitor (AI), or placebo daily for 12 months.

MAIN OUTCOME MEASURES

The primary outcome was prostate volume measured by transrectal ultrasound at baseline and 12 months. Secondary outcomes included prostate-specific antigen levels and lower urinary tract symptoms score.

RESULTS

Serum T levels increased in both intervention groups; estradiol levels increased in the TT group, whereas it decreased in the AI group. At 12 months, prostate volume significantly increased (4.5 ± 1.76 cc, P < .05) only in the TT group. Increase in prostate-specific antigen levels were seen in both intervention groups at 6 months (P < .01 and P < .001). The lower urinary tract symptoms score increased only in the TT group (P < .05).

CONCLUSIONS

The tropic effects of T on the prostate are mediated via its aromatization to estradiol. Administration of AI for 12 months to older men was not detrimental to the prostate.

Comparison of the Effects of Testosterone Gels, Injections, and Pellets on Serum Hormones, Erythrocytosis, Lipids, and Prostate-Specific Antigen

Introduction

Numerous testosterone (T) formulations are available, each with differing effects on serum parameters.

Aim

The aim of this study was to compare the long-term effects of topical, injectable, and implantable pellet T formulations in hypogonadal men.

Methods

Retrospective review of hypogonadal men treated with a single T formulation was performed: 47 men on T gels, 57 on injectable T, and 74 on T pellets were identified. Total T (TT), calculated free T (FT), estradiol (E), hemoglobin (Hgb), hematocrit (Hct), prostate-specific antigen (PSA), total cholesterol (Tchol), triglycerides (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) cholesterol were evaluated at baseline and every 3–6 months for 3 years. Serum parameters were compared using a mixed model linear regression for repeated measures.

Main Outcome Measures

Effects of topical, injectable, and pellet T formulations on serum hormone levels, Hgb, Hct, lipid parameters and PSA.

Results

Men in the injectable T group were younger (42.5 ± 12.3 years) than in the gel (54.1 ± 9.8 years) or pellet groups (53.8 ± 13.0 years), and baseline FT, Hgb, and Hct were higher in the injectable T group than in gel or pellet groups. Increases in TT and FT were observed throughout follow-up in all groups. Increases in E were observed at in all T groups and throughout follow-up in injectable and gel groups. No PSA increases were observed. Erythrocytosis (Hct > 50%) was more common with injectable T (66.7%) than with T gels (12.8%) or pellets (35.1%, P < 0.0001). Transient changes in cholesterol, TG, and LDL were observed, and no significant changes were seen in HDL for any group.

Conclusions

All T formulations increase serum T and FT. More significant increases in E occur with injectable T and T gels. Changes in Hgb and Hct are most significant with injectable T, and effects on lipids are variable and inconsistent. Selection of T formulations must account for individual patient preferences and the effects of each formulation.

Recommendations on the diagnosis, treatment and monitoring of hypogonadism in men

Hypogonadism or Testosterone Deficiency (TD) in adult men as defined by low levels of serum testosterone accompanied by characteristic symptoms and/or signs as detailed further on can be found in long-recognized clinical entities such as Klinefelter syndrome, Kallmann syndrome, pituitary or testicular disorders, as well as in men with idiopathic, metabolic or iatrogenic conditions that result in testosterone deficiency. These recommendations do not encompass the full range of pathologies leading to hypogonadism (testosterone deficiency), but instead focus on the clinical spectrum of hypogonadism related to metabolic and idiopathic disorders that contribute to the majority of cases that occur in adult men.

Association of sex hormones with sexual function, vitality, and physical function of symptomatic older men with low testosterone levels at baseline in the testosterone trials

CONTEXT

The prevalence of sexual dysfunction, low vitality, and poor physical function increases with aging, as does the prevalence of low total and free testosterone (TT and FT) levels. However, the relationship between sex hormones and age-related alterations in older men is not clear.

OBJECTIVE

To test the hypotheses that baseline serum TT, FT, estradiol (E2), and sex hormone-binding globulin (SHBG) levels are independently associated with sexual function, vitality, and physical function in older symptomatic men with low testosterone levels participating in the Testosterone Trials (TTrials).

DESIGN

Cross-sectional study of baseline measures in the TTrials.

SETTING

The study was conducted at 12 sites in the United States.

PARTICIPANTS

The 788 TTrials participants were ≥ 65 years and had evidence of sexual dysfunction, diminished vitality, and/or mobility disability, and an average of two TT < 275 ng/dL.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Question 4 of Psychosocial Daily Questionnaire (PDQ-Q4), the FACIT-Fatigue Scale, and the 6-minute walk test.

RESULTS

Baseline serum TT and FT, but not E2 or SHBG levels had small, but statistically significant associations with validated measures of sexual desire, erectile function, and sexual activity. None of these hormones was significantly associated within or across trials with FACIT-Fatigue, PHQ-9 Depression or Physical Function-10 scores, or gait speed.

CONCLUSIONS

FT and TT levels were consistently, independently, and positively associated, albeit to a small degree, with measures of sexual desire, erectile function, and sexual activity, but not with measures of vitality or physical function in symptomatic older men with low T who qualified for the TTrials.

The Role of the Multiple Hormonal Dysregulation in the Onset of "Anemia of Aging": Focus on Testosterone, IGF-1, and Thyroid Hormones

Anemia is a multifactorial condition whose prevalence increases in both sexes after the fifth decade of life. It is a highly represented phenomenon in older adults and in one-third of cases is "unexplained." Ageing process is also characterized by a "multiple hormonal dysregulation" with disruption in gonadal, adrenal, and somatotropic axes. Experimental studies suggest that anabolic hormones such as testosterone, IGF-1, and thyroid hormones are able to increase erythroid mass, erythropoietin synthesis, and iron bioavailability, underlining a potential role of multiple hormonal changes in the anemia of aging. Epidemiological data more consistently support an association between lower testosterone and anemia in adult-older individuals. Low IGF-1 has been especially associated with anemia in the pediatric population and in a wide range of disorders. There is also evidence of an association between thyroid hormones and abnormalities in hematological parameters under overt thyroid and euthyroid conditions, with limited data on subclinical statuses. Although RCTs have shown beneficial effects, stronger for testosterone and the GH-IGF-1 axis and less evident for thyroid hormones, in improving different hematological parameters, there is no clear evidence for the usefulness of hormonal treatment in improving anemia in older subjects. Thus, more clinical and research efforts are needed to investigate the hormonal contribution to anemia in the older individuals.

Human androgen deficiency: insights gained from androgen receptor knockout mouse models

The mechanism of androgen action is complex. Recently, significant advances have been made into our understanding of how androgens act via the androgen receptor (AR) through the use of genetically modified mouse models. A number of global and tissue-specific AR knockout (ARKO) models have been generated using the Cre-loxP system which allows tissue- and/or cell-specific deletion. These ARKO models have examined a number of sites of androgen action including the cardiovascular system, the immune and hemopoetic system, bone, muscle, adipose tissue, the prostate and the brain. This review focuses on the insights that have been gained into human androgen deficiency through the use of ARKO mouse models at each of these sites of action, and highlights the strengths and limitations of these Cre-loxP mouse models that should be considered to ensure accurate interpretation of the phenotype.

The impact of drug reimbursement policy on rates of testosterone replacement therapy among older men

Background

Despite a lack of data describing the long-term efficacy and safety of testosterone replacement therapy (TRT), prescribing of testosterone to older men has increased with the availability of topical formulations. The magnitude of this increase and the impact of formulary restrictions on testosterone prescribing are poorly characterized.

Methods

We conducted a time series analysis using the linked health administrative records of men aged 66 years or older in Ontario, Canada between January 1, 1997 and March 31, 2012. We used interventional autoregressive integrated moving average models to examine the impact of a restrictive drug reimbursement policy on testosterone prescribing and examined the demographic profile of men initiating testosterone in the final 2 years of the study period.

Results

A total of 28,477 men were dispensed testosterone over the study period. Overall testosterone prescribing declined 27.9% in the 6 months following the implementation of the restriction policy (9.5 to 6.9 men per 1000 eligible; p<0.01). However, the overall decrease was temporary and testosterone use exceeded pre-policy levels by the end of the study period (11.0 men per 1000 eligible), largely driven by prescriptions for topical testosterone (4.8 men per 1000 eligible). Only 6.3% of men who initiated testosterone had a documented diagnosis of hypogonadism, the main criteria for TRT reimbursement according to the new policy.

Conclusion

Government-imposed restrictions did not influence long-term prescribing of testosterone to older men. By 2012, approximately 1 in every 90 men aged 66 or older was being treated with TRT, most with topical formulations.