AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY POSITION STATEMENT ON THE ASSOCIATION OF TESTOSTERONE AND CARDIOVASCULAR RISK

EMAS position statement: Testosterone replacement therapy in older men

INTRODUCTION

Late-onset hypogonadism is the clinical entity characterised by low testosterone concentrations associated with clinical symptoms in the absence of organic disease in ageing men. It has been associated with metabolic syndrome, reduced bone mineral density, and increased cardiovascular morbidity and mortality risk. Although testosterone replacement therapy (TRT) reverses most of these conditions in young hypogonadal men, the risk/benefit ratio of TRT in older men is debatable.

AIM

To update the 2015 EMAS statement on TRT in older men with new research on late-onset hypogonadism and TRT.

MATERIALS AND METHODS

Literature review and consensus of expert opinion.

SUMMARY RECOMMENDATIONS

TRT should be offered only to symptomatic older men with confirmed low testosterone concentrations after explaining the uncertainties regarding the long-term safety of this treatment. TRT may be offered to men with severe hypogonadism and erectile dysfunction to improve sexual desire, erectile, and orgasmic function. It should also be considered in hypogonadal men with severe insulin resistance or pre-diabetes mellitus. TRT may also be considered, in combination with proven treatment strategies, for osteoporosis, or for selected patients with persistent mild depressive symptoms and/or low self-perceived quality of life, combined with standard medical care for each condition. TRT is contraindicated in hypogonadal men actively seeking fertility treatment. Due to a lack of data, TRT should not be routinely used in older men to improve exercise capacity/physical function, improve cognitive function, or prevent cognitive decline. TRT must be avoided in older, frail men with known breast cancer or untreated prostate cancer and all men who have had myocardial infarction or stroke within the last four months, and those with severe or decompensated heart failure. The quality of evidence regarding patients with previous prostate cancer or cardiovascular disease is too low to draw definitive conclusions. Any limits on duration of use are arbitrary, and treatment should continue for as long as the man feels the benefits outweigh the risks for him, and decisions must be made on an individual basis. Withdrawal should be considered when hypogonadism is reversed after the resolution of underlying disorder. Short-acting transdermal preparations should be preferred for TRT initiation in older men, but injectable forms may be considered subsequently. Older men on TRT should be monitored at 3, 6, and 12 months after initiation and at least yearly thereafter, or earlier and more frequently if indicated. Evaluation should include assessment of the clinical response, and measurement of total testosterone, haematocrit, and prostate-specific antigen (PSA) concentrations. Bone density and/or quality should also be assessed. Obese and overweight patients should be encouraged to undergo lifestyle modifications, including exercise and weight loss, to increase endogenous testosterone.

Oral administration of VDAC1-derived small molecule peptides increases circulating testosterone levels in male rats

Cholesterol is the precursor of all steroid hormones, and the entry of cholesterol into the mitochondria is the rate-limiting step of steroidogenesis. Voltage-dependent anion channel (VDAC1) is an outer mitochondrial protein part of a multiprotein complex that imports cholesterol. We previously reported that intratesticular administration of a 25 amino acid peptide blocking the interaction between 14-3-3ϵ with VDAC1 increased circulating levels of testosterone. This fusion peptide was composed of a HIV-1 transactivator of transcription (TAT) protein transduction domain cell-penetrating peptide, a glycine linker, and amino acids 159-172 of VDAC1 (TV159-172). Here, we describe the development of a family of small molecules that increase circulating testosterone levels after an oral administration. We first characterized an animal model where TV159-172 was delivered subcutaneously. This subcutaneous model allowed us to study the interactions between TV159-172 and the hypothalamus-pituitary-gonadal axis (HPG) and identify the biologically active core of TV159-172. The core consisted of the tetrapeptide RVTQ, which we used as a platform to design synthetic peptide derivatives that can be administered orally. We developed a second animal model to test various derivatives of RVTQ and found 11 active compounds. Dose-response experiments identified 4 synthetic peptides that robustly increased androgen levels in a specific manner. We selected RdVTQ as the leading VDAC1-core derivative and profiled the response across the lifespan of Brown-Norway rats. In summary, we present the development of a new class of therapeutics that act within the HPG axis to increase testosterone levels specifically. This new class of small molecules self-regulates, preventing abuse.

Trends in testosterone prescription amongst medical specialties: a 5-year CMS data analysis

Testosterone Therapy (TTh) trends have changed as a result of clinical research and market forces over the past several years. Understanding the trends or preferences regarding testosterone prescriptions remains unknown. Our objective was to assess both regional and national trends in TTh prescriptions amongst medical specialties within the United States between 2013 and 2017. Publicly available data from the Center for Medicare and Medicaid Services (CMS) Part D Prescriber database with regards to TTh prescriptions across a 5-year span (January 1, 2013-December 31, 2017) were analyzed. TTh therapies were consolidated into four categories: Topical, Oral, Injection and Pellet. Statistical analysis utilizing R 4.0.2 was performed on the resulting data. Trends in prescription modality claim count and cost were plotted over the study period while statistical analysis evaluated associations between TTh modality and medical specialist. We found that Endocrinologists and Urologists prescribed topical testosterone more than all other specialties (60.4% and 53.5%, respectively), while Family and Internal medicine physicians were more likely to prescribe injections (59.82% and 50.69%, respectively). Oral and pellet testosterone were rarely prescribed across all specialties. In conclusion, the wide variation in modalities of testosterone prescriptions illustrates an opportunity for treatment guidelines to be streamlined across all specialists to improve patient outcomes.

How Would You Manage This Male Patient With Hypogonadism? : Grand Rounds Discussion From Beth Israel Deaconess Medical Center

Male hypogonadism is defined as an abnormally low serum testosterone concentration or sperm count. As men age, often in the context of obesity and other comorbid conditions, serum testosterone levels may decrease. Normalizing serum testosterone levels in male adults with hypogonadism may improve symptoms related to androgen deficiency, but controversies exist regarding the long-term benefits and risks of hormone supplementation in this setting. In 2020, the American College of Physicians published a clinical guideline for the use of testosterone supplementation in adult men based on a systematic review of available evidence. Among their recommendations were that clinicians discuss whether to initiate testosterone treatment in men with age-related low testosterone with sexual dysfunction who want to improve sexual function and not initiate testosterone treatment in men with age-related low testosterone to improve energy, vitality, physical function, or cognition. Here, two clinicians with expertise in this area, one a generalist and the other an endocrinologist, debate the management of a patient with sexual symptoms and a low serum testosterone level. They discuss the diagnosis of male hypogonadism, the indications for testosterone therapy, its potential benefits and risks, how it should be monitored, and how long it should be continued.

Advances in stem cell research for the treatment of primary hypogonadism

In Leydig cell dysfunction, cells respond weakly to stimulation by pituitary luteinizing hormone, and, therefore, produce less testosterone, leading to primary hypogonadism. The most widely used treatment for primary hypogonadism is testosterone replacement therapy (TRT). However, TRT causes infertility and has been associated with other adverse effects, such as causing erythrocytosis and gynaecomastia, worsening obstructive sleep apnoea and increasing cardiovascular morbidity and mortality risks. Stem-cell-based therapy that re-establishes testosterone-producing cell lineages in the body has, therefore, become a promising prospect for treating primary hypogonadism. Over the past two decades, substantial advances have been made in the identification of Leydig cell sources for use in transplantation surgery, including the artificial induction of Leydig-like cells from different types of stem cells, for example, stem Leydig cells, mesenchymal stem cells, and pluripotent stem cells (PSCs). PSC-derived Leydig-like cells have already provided a powerful in vitro model to study the molecular mechanisms underlying Leydig cell differentiation and could be used to treat men with primary hypogonadism in a more specific and personalized approach.

Efficacy of testosterone replacement therapy for treating metabolic disturbances in late-onset hypogonadism: a systematic review and meta-analysis

PURPOSE

Late onset hypogonadism (LOH) is an age-dependent reduction of testosterone associated with alterations of metabolic profile, including glucose control, insulin sensitivity, and lipid profile. The purpose of this study was to investigate the efficacy of testosterone replacement therapy (TRT) for treating metabolic disturbances through a meta-analysis of randomized clinical trials (RCTs).

METHODS

A systematic review of literature published from 1964 to November, 2019 was performed using the PubMed/Medline, Embase, and Cochrane databases. Among the 1562 articles screened, 17 articles were selected for qualitative analysis and 16 articles (n = 1373) were included for data synthesis following the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). Criteria for final inclusion were RCTs.

RESULTS

Sixteen studies were finally included (TRT group, n = 709; placebo group, n = 664). Among the metabolic markers, HbA1C [Mean difference (MD) = - 0.172, 95% CI - 0.329, - 0.015], HOMA IR (MD = - 0.514, 95% CI - 0.863, - 0.165), serum insulin (MD = - 12.622, 95% CI - 19.660, - 5.585), and leptin (MD = - 2.381, 95% CI - 2.952, - 1.810) showed significant improvement after TRT versus placebo. Among the lipid profiles, total cholesterol showed significant improvement (MD = - 0.433, 95% CI - 0.761, - 0.105) after TRT. However, HDL showed a decrease (MD = - 0.069, 95% CI - 0.121, - 0.018) after TRT. Among anthropometric markers, waist circumference showed significant improvement (MD = - 0.1640, 95% CI - 2.857, - 0.423).

CONCLUSION

This study demonstrated greater improvement in metabolic profiles for patients given TRT versus placebo. Further well-designed trials are needed to verify our findings and further elucidate effects of TRT on lipid profiles. This systematic review demonstrates that TRT can exert a net beneficial effect on metabolic profiles.

Diagnosis and Management of Testosterone Deficiency in men: A review of the European and American Urology Associations

Ambiguous data on both terminology, diagnostics, and treatment of testosterone deficiency in men prompted us to attempt a critical analysis of existing knowledge on this subject. Current guidelines of both American and European Association of Urology (AUA, EUA) define testosterone therapy as effective and safe. However, media reports and some scientific reports indicating negative effects of the abovementioned therapy arouse aversion to its use by doctors and potential patients for fear of developing prostate cancer or cardiovascular incidents. The peak of scepticism about testosterone therapy was observed after the publication in 2013 and 2014, respectively, two retrospective data analysis on this topic, which resulted in the discontinuation of therapy in many patients with long histories of benefits from testosterone therapy. In addition, in many men with indications for testosterone therapy, this treatment was not used for fear of patient safety. However, the latest data on these concerns do not confirm any negative effects. More than 100 recently published scientific studies have shown the beneficial effects of testosterone therapy on many aspects of health. The American Society of Clinical Endocrinologists (AACE) and the American College of Endocrinology (ACE) have jointly developed their own literature assessment, stating that there is no convincing evidence that testosterone therapy increases the risk of cardiovascular incidents. The same conclusions can be drawn from the current EAU and AUA guidelines.

Leydig cell aging: Molecular mechanisms and treatments

Late-onset hypogonadism, resulting from deficiency in serum testosterone (T), affects the health and quality of life of millions of aging men. T is synthesized by Leydig cells (LCs) in response to luteinizing hormone (LH). LH binds LC plasma membrane receptors, inducing the formation of a supramolecular complex of cytosolic and mitochondrial proteins, the Steroidogenic InteracTomE (SITE). SITE proteins are involved in targeting cholesterol to CYP11A1 in the mitochondria, the first enzyme of the steroidogenic cascade. Cholesterol translocation is the rate-determining step in T formation. With aging, LC defects occur that include changes in SITE, an increasingly oxidative intracellular environment, and reduced androgen formation and serum T levels. T replacement therapy (TRT) will restore T levels, but reported side effects make it desirable to develop additional strategies for increasing T. One approach is to target LC protein-protein interactions and thus increase T production by the hypofunctional Leydig cells themselves.

Neutral effect of exenatide on serum testosterone in men with type 2 diabetes mellitus: A prospective cohort

BACKGROUND

Endogenous testosterone increases with weight loss from diet, exercise, and bariatric surgery. However, little is known about testosterone levels after weight loss from medication.

OBJECTIVES

Uncover the effects of Glucagon-Like Peptide-1 receptor agonist (GLP-1 RA) therapy on serum testosterone.

MATERIAL AND METHODS

Prospective cohort study of men starting GLP-1 RA therapy for type 2 diabetes mellitus.

RESULTS

51 men lost 2.27 kg (p = 0.00162) and their HbA1c values improved by 0.7% (p = 0.000503) after 6 months of GLP-1 RA therapy. There was no significant change in testosterone for the group as a whole. However, in subgroup analyses, there was a significant difference in total testosterone change between men starting with baseline total testosterone <320 ng/dL (238.5 ± 56.5 ng/dL to 272.2 ± 82.3 ng/dL) compared to higher values (438 ± 98.2 ng/dL to 412 ± 141.2 ng/dL) (p = 0.0172);free testosterone increased if the baseline total testosterone was <320 ng/dL (55.2 ± 12.8 pg/mL to 57.2 ± 17.6 pg/mL) and decreased if >320 ng/dL (74.7 ± 16.3 pg/mL to 64.2 ± 17.7 pg/mL) (p = 0.00807). Additionally, there were significant differences in testosterone change between men with HbA1c improvements ≥1% (351.6 ± 123.9 ng/dL to 394.4 ± 136.5 ng/dL) compared to men with HbA1c changes <1% (331.8 ± 128.6 ng/dL to 316.1 ± 126.2 ng/dL) (p = 0.0413).

CONCLUSION

GLP-1 RA therapy improves weight and HbA1c without adverse effects on testosterone. Those starting with lower testosterone values or attaining greater improvement in HbA1c may see additional benefits.

Mechanisms underlying the metabolic actions of testosterone in humans: A narrative review

The role of testosterone in improving sexual symptoms in men with hypogonadism is well known. However, recent studies indicate that testosterone plays an important role in several metabolic functions in males. Multiple PubMed searches were conducted with the use of the terms testosterone, insulin sensitivity, obesity, type 2 diabetes, anaemia, bone density, osteoporosis, fat mass, lean mass and body composition. This narrative review is focused on detailing the mechanisms that underlie the metabolic aspects of testosterone therapy in humans. Testosterone enhances insulin sensitivity in obese men with hypogonadism by decreasing fat mass, increasing lean mass, decreasing free fatty acids and suppressing inflammation. At a cellular level, testosterone increases the expression of insulin receptor β subunit, insulin receptor substrate-1, protein kinase B and glucose transporter type 4 in adipose tissue and adenosine 5'-monophosphate-activated protein kinase expression and activity in skeletal muscle. Observational studies show that long-term therapy with testosterone prevents progression from prediabetes to diabetes and improves HbA1c. Testosterone increases skeletal muscle satellite cell activator, fibroblast growth factor-2 and decreases expression of the muscle growth suppressors, myostatin and myogenic regulatory factor 4. Testosterone increases haematocrit by suppressing hepcidin and increasing expression of ferroportin along with that of transferrin receptor and plasma transferrin concentrations. Testosterone also increases serum osteocalcin concentrations, which may account for its anabolic actions on bone. In conclusion, testosterone exerts a series of potent metabolic effects, which include insulin sensitization, maintenance and growth of the skeletal muscle, suppression of adipose tissue growth and maintenance of erythropoiesis and haematocrit.

Hypogonadism and metabolic syndrome: review and update

PURPOSE OF REVIEW

The prevalence of metabolic syndrome and hypogonadism continues to rise in the United States and around the world. These two conditions are inexorably linked, and understanding their relationship with each other is key to treating men with either of these conditions.

RECENT FINDINGS

Testosterone has been shown to be a key regulator in the maintenance of metabolic homeostasis. A large volume of research has found that testosterone deficiency is closely linked to metabolic syndrome through complex physiologic mechanisms of endothelial dysfunction, inflammation, and glucose metabolism.

SUMMARY

Interventions through lifestyle modification and testosterone replacement in hypogonadal men may reduce the morbidity and mortality risks associated with metabolic syndrome.

Testosterone deficiency in men infected with COVID ‐19

As our understanding of the SARS‐CoV‐2 virus develops, recent research has highlighted the potential role of testosterone in the severity of illness. Here, the authors explain the role of testosterone in men infected with COVID‐19.

Why does COVID-19 kill more elderly men than women? Is there a role for testosterone?

Background

Recent epidemiological data indicate that there may be a gender predisposition to COVID‐19, with men predisposed to being most severely affected, and older men accounting for most deaths.

Objectives

Provide a review of the research literature, propose hypotheses, and therapies based on the potential link between testosterone (T) and COVID‐19 induced mortality in elderly men.

Materials and Methods

A search of publications in academic electronic databases, and government and public health organization web sites on T, aging, inflammation, severe acute respiratory syndrome (SARS) due to coronavirus (CoV) 2 (SARS‐CoV‐2) infection, and COVID‐19 disease state and outcomes was performed.

Results

The link between T, the immune system, and male aging is well‐established, as is the progressive decline in T levels with aging. In women, T levels drop before menopause and variably increase with advanced age. Elevated IL‐6 is a characteristic biomarker of patients infected with COVID‐19 and has been linked to the development of the acute respiratory distress syndrome (ARDS). Thus far, half of the admitted COVID‐19 patients developed ARDS, half of these patients died, and elderly male patients have been more likely to develop ARDS and die. Low T is associated with ARDS. These data suggest that low T levels may exacerbate the severity of COVID‐19 infection in elderly men. It may also stand to reason that normal T levels may offer some protection against COVID‐19. SARS‐CoV‐2 binds to the angiotensin‐converting enzyme 2, present in high levels in the testis.

Conclusion

At present, it is not known whether low T levels in aging hypogonadal males create a permissive environment for severe responses to COVID‐19 infection or if the virus inhibits androgen formation. Given the preponderance of COVID‐19 related mortality in elderly males, additional testing for gonadal function and treatment with T may be merited.

Testosterone replacement therapy and the risk of adverse cardiovascular outcomes and mortality

Background

The risk of adverse cardiovascular events and mortality associated with testosterone replacement therapy is controversial. The purpose of this report was to evaluate the effect of testosterone replacement therapy (TRT) in men with secondary hypogonadism on the risk of myocardial infarction (MI), stroke (CVA) or all-cause mortality.

Methods

A retrospective cohort study was conducted using the Cleveland Clinic’s electronic health record. Men ≥40 years of age, with at least two testosterone levels < 220 ng/dL, with one level obtained between 7 am and 10 am, were identified. Men with primary hypogonadism, secondary hypogonadism related to overt hypothalamic pituitary pathology, human immunodeficiency virus infection, metastatic cancer, and select contraindications to TRT, were excluded. Men exposed to TRT were matched to controls that were not exposed. A survival analysis was performed on the composite outcome of MI, CVA, or all-cause mortality.

Results

One hundred sixty-five patients exposed to TRT (treatment group) were matched with 210 not exposed to TRT (comparison group). The prevalence of established cardiovascular disease (CVD) was 20.0% in the treatment group vs. 17.1% in the comparison group (P = 0.478). The median [interquartile range (IQR)] age (years) and BMI (kg/m²) were 55 (49, 62) and 35.6 (32.1, 40.1) in the treatment group, and 55 (49, 61.7) and 36.3 (32.1, 40.8) in the comparison group, respectively. There were 12 (7.3%) events observed in the treatment group, and 16 (7.6%) in the comparison group. The median time (years) to the composite event was 2.1 (IQR 0.9, 4.6) and 1.8 (IQR 0.6, 3.4) for treatment and comparison groups, respectively. No difference in the risk of the combined cardiovascular endpoint was observed between the treatment group vs the comparison group, hazard ratio (HR) 0.81 (95% Confidence Interval [CI]: 0.38–1.71; P = 0.57).

Conclusion

In hypogonadal men with a modest prevalence of established CVD, TRT was not observed to confer a protective or adverse effect on the risk of MI, CVA or all-cause mortality.

Metabolic Effects of Testosterone Therapy in Men with Type 2 Diabetes and Metabolic Syndrome

INTRODUCTION

Up to 40% of men with type 2 diabetes (T2DM) and metabolic syndrome (MetS) have hypogonadotrophic hypogonadism (HH). Men with HH are at increased risk of cardiovascular (CV) and all-cause mortality, as well as of the development of incident T2DM.

AIM

To review the current literature on the metabolic effects of testosterone therapy (TTh) in men with T2DM and MetS.

METHODS

We searched MEDLINE, Embase, and Cochrane Reviews for articles on T2DM, HH, testosterone deficiency, and CV and all-cause mortality published between May 2005 and July 2018, yielding 1817 articles, including 54 clinical trials and 32 randomized controlled trials (RCTs).

MAIN OUTCOME MEASURES

The main outcomes were glycemic control, insulin resistance, lipid profile, and metabolic markers associated with increased CV risk.

RESULTS

RCTs of TTh suggest significant benefits for sexual function, quality of life, glycemic control, insulin sensitivity, anemia, bone density, and fat and lean muscle mass that might be expected to translate into reduced long-term morbidity and mortality. Several longitudinal and observational studies suggest long-term sustained improvements in metabolic parameters and a trend toward reduced CV and all-cause mortality, especially in men at increased CV risk, such as those with T2DM and MetS. The greatest benefit is seen in those men treated with TTh to target levels and for longer durations.

CONCLUSION

Meta-analyses of RCTs, rather than providing clarification, may have further confused the issue by including underpowered studies of inadequate duration, multiple therapy regimens, some obsolete or withdrawn, and built-in bias in terms of studies included or excluded from analysis. Hackett G. Metabolic Effects of Testosterone Therapy in Men with Type 2 Diabetes and Metabolic Syndrome. Sex Med Rev 2019;7:476-490.

Male and Female Hypogonadism

Hypogonadism is a clinical syndrome that results in hormone deficiency in men and women. Primary hypogonadism is caused by gonadal (testicular or ovarian) failure. Secondary hypogonadism is the result of a dysfunction within the hypothalamus and/or pituitary. Diagnosis of hypogonadism requires a comprehensive health history, evaluation of the signs and symptoms, complete physical examination, as well as laboratory and diagnostic testing for both sexes. Hormone replacement is the hallmark of hypogonadism treatment. Restoring and/or maintaining quality of life is a major consideration in the management of patients with hypogonadism.

Effects of testosterone and progressive resistance exercise on vascular function in older men

The cardiovascular effects of testosterone (T) are controversial. Low T has been associated with accelerated vascular aging, characterized by large elastic artery stiffening (decreased compliance), intimal-medial thickening (IMT), and endothelial dysfunction. Endurance exercise improves vascular function, but resistance training may increase arterial stiffness. We sought to determine whether T supplementation improved markers of vascular aging in men with low-normal T and whether T supplementation prevented arterial stiffness with resistance exercise. We studied 160 community-dwelling older men (66 ± 5 yr) with low-normal baseline total T levels (200-350 ng/dl). Participants were randomized to transdermal T gel targeting either a lower (400-550 ng/dl) or higher (600-1,000 ng/dl) T range or to placebo gel and to either progressive resistance training (PRT) or to no exercise for 12 mo. Carotid artery stiffness (arterial compliance) and carotid IMT were measured at baseline, 6 mo, and 12 mo. Endothelial function (brachial artery flow-mediated dilation) was measured in a subset (n = 86). Changes in carotid artery compliance, IMT, and endothelial function with either the lower or higher range of T supplementation were not different from placebo at 6 or 12 mo. There were no differences between PRT and no PRT groups, alone or with T supplementation, in changes in any of the vascular measures at either time point. Supplementation of T and PRT in older men with low-normal levels do not appear to improve or harm vascular function.NEW & NOTEWORTHY Increased promotion and prescription of testosterone (T) to aging men has raised concerns about potential adverse cardiovascular effects. We show that in older men with T levels in the low-normal range, 12 mo of T supplementation with or without resistance exercise did not improve or harm vascular function.

Testosterone replacement therapy: For whom, when and how?

The finding of low circulating testosterone level in men is relatively frequent. The symptoms of hypogonadism are very frequent in the aging men. However, the diagnosis of hypogonadism is often neglected and the opportunity to replace low testosterone in older men is highly debated. The aim of this narrative review is to summarize the steps necessary to formulate a proper diagnosis and to guide toward an individualized treatment. While universally recognized the need to treat the young adults with known causes of pituitary or testicular failure, there are controversies on the cost-benefit of treating testosterone deficiency in older men. Discrepancies among the several available guidelines do not help to clarify the scenario, however, the recent larger clinical trials have shed some light on the fact that testosterone treatment carries some benefit, that is not free from risks. We provide an updated review of the diagnostic hallmarks, the several treatment modalities, with their advantages and disadvantages, and how to individualize and monitor treatment in order to maximize the benefits and minimize the risks. The treatment of male hypogonadism can no longer be downgraded and must become part of the cultural baggage of the endocrinologist.

Type 2 Diabetes and Testosterone Therapy

A third of men with type 2 diabetes (T2DM) have hypogonadotrophic hypogonadism (HH) and associated increased risk of cardiovascular and all-cause mortality. Men with HH are at increased risk of developing incident T2DM. We conducted MEDLINE, EMBASE, and COCHRANE reviews on T2DM, HH, testosterone deficiency, cardiovascular and all-cause mortality from May 2005 to October 2017, yielding 1,714 articles, 52 clinical trials and 32 randomized controlled trials (RCT). Studies with testosterone therapy suggest significant benefits in sexual function, quality of life, glycaemic control, anaemia, bone density, fat, and lean muscle mass. Meta-analyses of RCT, rather than providing clarification, have further confused the issue by including under-powered studies of inadequate duration, multiple regimes, some discontinued, and inbuilt bias in terms of studies included or excluded from analysis.

Hypogonadotropic Hypogonadism in Men With Diabesity

One-third of men with obesity or type 2 diabetes have subnormal free testosterone concentrations. The lower free testosterone concentrations are observed in obese men at all ages, including adolescents at completion of puberty. The gonadotropin concentrations in these males are inappropriately normal; thus, these patients have hypogonadotropic hypogonadism (HH). The causative mechanism of diabesity-induced HH is yet to be defined but is likely multifactorial. Decreased insulin and leptin signaling in the central nervous system are probably significant contributors. Contrary to popular belief, estrogen concentrations are lower in men with HH. Men with diabesity and HH have more fat mass and are more insulin resistant than eugonadal men. In addition, they have a high prevalence of anemia and higher mortality rates than eugonadal men. Testosterone replacement therapy results in a loss of fat mass, gain in lean mass, and increase in insulin sensitivity in men with diabesity and HH. This is accompanied by an increase in insulin-signaling genes in adipose tissue and a reduction in inflammatory mediators that interfere with insulin signaling. There is also an improvement in sexual symptoms, anemia, LDL cholesterol, and lipoprotein (a). However, testosterone therapy does not consistently affect HbA_1c in men with diabetes. The effect of testosterone replacement on cardiovascular events or mortality in men with diabesity is not known and remains to be studied in prospective trials.

Role of androgens in energy metabolism affecting on body composition, metabolic syndrome, type 2 diabetes, cardiovascular disease, and longevity: lessons from a meta-analysis and rodent studies

Testosterone is a sex hormone produced by testicular Leydig cells in males. Blood testosterone concentrations increase at three time-periods in male life-fetal, neonatal (which can be separated into newborn and infant periods), and pubertal stages. After peaking in the early 20s, the blood bioactive testosterone level declines by 1-2% each year. It is increasingly apparent that a low testosterone level impairs general physical and mental health in men. Here, this review summarizes recent systematic reviews and meta-analyses of epidemiological studies in males (including cross-sectional, longitudinal, and androgen deprivation studies, and randomized controlled testosterone replacement trials) in relation to testosterone and obesity,  body composition, metabolic syndrome, type 2 diabetes, cardiovascular disease, and longevity. Furthermore, underlying mechanisms are discussed using data from rodent studies involving castration or androgen receptor knockout. This review provides an update understanding of the role of testosterone in energy metabolism. Abbreviations AR: androgen receptor; CV: cardiovascular; FDA: US Food and Drug Administration; HFD: high-fat diet; KO: knockout; MetS: metabolic syndrome; RCT: randomized controlled trial; SHBG: sex hormone binding globulin; SRMA: systematic review and meta-analysis; TRT: testosterone replacement therapy; T2DM:type 2 diabetes mellitus.

GONADOPENIA AND AGING IN MEN

OBJECTIVE

The decrease in testosterone levels that occurs with aging has become an important clinical issue both due to the growth of the geriatric population and patient interest in testosterone therapy. The decision to assess for testosterone deficiency and the ability to determine whether the benefits exceed the risks require a comprehensive evaluation of the aging patient. This article is part of a series of papers focused on the endocrinology of aging. This review addresses common issues needed for clinical decision making, including how to interpret test results, differential diagnosis, potential impact of testosterone treatment on insulin resistance and cardiovascular disease, and options for therapy.

METHODS

Papers reviewed were identified through literature searches conducted on PubMed.

RESULTS

Assessment of testosterone levels in the geriatric male requires an understanding of the limitations of the assay that is used, the symptoms associated with low testosterone, the impact of comorbid conditions on levels, and risks of therapy. Successful treatment requires setting realistic expectations of the benefits of replacement therapy.

CONCLUSION

While the prevalence of low testosterone concentrations is increased with aging, the common comorbidities such as obesity and diabetes may contribute to changes in testosterone levels. Clinical trial evidence shows modest benefit for treatment of low testosterone in the presence of symptoms. Assessment of the geriatric male should include evaluation of their testosterone level in the context of their functional status and comorbidities.

ABBREVIATIONS

CDC = Centers for Disease Control and Prevention; CI = confidence interval; CVD = cardiovascular disease; DXA = dual-energy X-ray absorptiometry; EMAS = European Male Aging Study; FDA = U.S. Food and Drug Administration; FHS = Framingham Heart Study; HDL = high-density lipoprotein; HOMA-IR = homeostasis model assessment of insulin resistance; LH = luteinizing hormone; OR = odds ratio; PSA = prostate-specific antigen; SHBG = sex hormone-binding globulin; T2DM = type 2 diabetes mellitus; vBMD = volumetric bone mineral density.

[Androgens and cardiovascular risk: A series of case report in the French and Canadian pharmacovigilance databases]

INTRODUCTION

Age-related androgenic deficiency (DALA) is a pathology that is increasingly cited in recent publications. The cardiovascular risk of testosterone is debated: present for the FDA, absent for the European Medicines Agency in 2015. Our objective was to analyze the association between androgens and vascular pathologies in adverse reactions reported in pharmacovigilance databases.

MATERIAL AND METHOD

We conducted a retrospective case series study of the French and Canadian pharmacovigilance databases for the period 2005-2015. Cases were defined as the association of the occurrence of a cardiovascular event (myocardial infarction or stroke) and the presence of testosterone in the treatment of patients.

RESULTS

Of the 10 years analyzed, 12 French cases and 6 Canadian cases (representing 13 MIs and 5 strokes) were recorded in men aged 55 years on average. All were doubtful: differential diagnoses were possible (2.4 confounding conditions on average per patient) and overall cardiovascular risk was high for the majority of cases.

CONCLUSION

Our study shows a very low report of cardiovascular effects under testosterone, all doubtful. Pending further studies, it seems reasonable to consider the cardiovascular risk of patients who are candidates for hormone therapy for age-related androgen deficiency.

LEVEL OF EVIDENCE

3.

Testosterone and Cardiovascular Health

There is an ongoing debate in the medical community regarding the effects of testosterone on cardiovascular (CV) health. For decades, there has been conflicting evidence regarding the association of endogenous testosterone levels and CV disease (CVD) events that has resulted in much debate and confusion among health care providers and patients alike. Testosterone therapy has become increasingly widespread, and after the emergence of studies that reported increased CVD events in patients receiving testosterone therapy, the US Food and Drug Administration (FDA) released a warning statement about testosterone and its potential risk regarding CV health. Some of these studies were later found to be critically flawed, and some experts, including the American Association of Clinical Endocrinologists and an expert panel regarding testosterone deficiency and its treatment, reported that some of the FDA statements regarding testosterone therapy were lacking scientific evidence. This article summarizes the current evidence regarding the relationship between testosterone (endogenous and supplemental) and CV health. A literature review was conducted via search using PubMed and specific journal databases, including the New England Journal of Medicine and the Journal of the American College of Cardiology. Key search terms included testosterone and cardiovascular health, coronary artery disease, heart failure, androgen deprivation therapy, intima-media thickness, and adrenal androgens. Initial study selection was limited to publications within the past 10 years (January 1, 2007, through December 31, 2016); however, key publications outside of this time frame were selected if they provided important quantitative data or historical perspectives for the review of this topic. The search was further supplemented by reviewing references in selected articles.

Practical Use of Pharmacotherapy for Obesity

Obesity management requires a multidisciplinary approach, as there are many factors that contribute to the development of obesity, as well as the preservation of excess weight once it has been gained. Diet, exercise, and behavior modification are key components of treatment. In addition to lifestyle changes, weight gain secondary to medications is an important modifiable risk factor. Even after appropriate lifestyle modification, and medication adjustments (where possible) to avoid agents that can contribute to weight gain, many patients are still unable to achieve clinically meaningful weight loss. Pharmacotherapy for obesity management can fill an important role for these patients. This article will review medications that can lead to weight gain and potential alternatives, currently approved anti-obesity medications and best practices to individualize the selection process, and the use of testosterone in men with hypogonadism and obesity.

Metabolic endotoxaemia related inflammation is associated with hypogonadism in overweight men

BACKGROUND

Obesity is associated with both impaired testosterone production and a chronic state of low grade inflammation. Previously it was believed that this inflammation was mediated by a decline in the immunosuppressive action of testosterone. However, more recently an alternative hypothesis (GELDING theory) has suggested that inflammation originating from the passage of intestinal bacteria into the circulation (metabolic endotoxaemia) may actually be the cause of impaired testicular function in obese men. The aim of this study is to investigate if metabolic endotoxaemia, as quantified by serum Lipopolysaccharide Binding Protein (LBP), is associated with impaired testicular endocrine function.

METHODS

A total of 50 men aged between 21 and 50 years (mean 35.1 ± 6.8 years) were assessed for adiposity (BMI, waist circumference and % body fat using bio-impedance), inflammatory status (serum CRP, IL-1β, IL-6, TNFα and LBP) and testicular endocrine function (serum testosterone, estradiol, AMH, LH and FSH). Statistical analysis was performed using Pearson correlation analysis, with log transformation of data where appropriate, and multi-variate regression.

RESULTS

Overall increasing adiposity (% body fat) was positively associated with metabolic endotoxaemia (LBP, r = 0.366, p = 0.009) and inflammation (CRP r = 0.531, p < 0.001; IL-6 r = 0.463, p = 0.001), while also being negatively correlated with serum testosterone (r = -0.403, p = 0.004). Serum testosterone levels were significantly negatively correlated with inflammation (CRP r = -0.471, p = 0.001; IL-6 r = -0.516, p < 0.001) and endotoxaemia (LBP) after adjusting for serum LH levels (p = -0.317, p = 0.03). Furthermore, serum IL-6 was negatively associated with AMH levels (r = -0.324, p = 0.023), with a negative trend between LBP and AMH also approaching significance (r = -0.267, p = 0.064).

CONCLUSIONS

Obesity and its associated metabolic endotoxaemia helps initiate a pro-inflammatory state characterised by raised serum IL-6 levels, which in turn is correlated with impairment of both Leydig (testosterone) and Sertoli cell function (AMH). These results open up the potential for new treatments of obesity related male hypogonadism that focus on preventing the endotoxaemia associated chronic inflammatory state.

UK policy statements on testosterone deficiency

To address widespread media and scientific concerns over the appropriate treatment of TDS with Testosterone Therapy (T Therapy), the Executive Committee of the British Society for Sexual Medicine developed eight consensus statements, based on current scientific evidence to address these controversial issues. These statements were in no-way designed to replace the published evidence-based guidelines on the subject developed by various professional organisations, but to provide specific answers to several current controversial issues. This review examined evidence from Medline, EMBASE and Cochrane searches on HG, T Therapy and cardiovascular safety from May 2005 to May 2015, which revealed 1714 articles, with 52 clinical trials and 32 placebo-controlled randomised controlled trials. The task force developed the following eight key statements.

Long-Term Testosterone Therapy Improves Cardiometabolic Function and Reduces Risk of Cardiovascular Disease in Men with Hypogonadism: A Real-Life Observational Registry Study Setting Comparing Treated and Untreated (Control) Groups

Objectives:

In the absence of large, prospective, placebo-controlled studies of longer duration, substantial evidence regarding the safety and risk of testosterone (T) therapy (TTh) with regard to cardiovascular (CV) outcomes can only be gleaned from observational studies. To date, there are limited studies comparing the effects of long-term TTh in men with hypogonadism who were treated or remained untreated with T, for obvious reasons. We have established a registry to assess the long-term effectiveness and safety of T in men in a urological setting. Here, we sought to compare the effects of T on a host of parameters considered to contribute to CV risk in treated and untreated men with hypogonadism (control group).

Patients and Methods:

Observational, prospective, cumulative registry study in 656 men (age: 60.7 ± 7.2 years) with total T levels ≤12.1 nmol/L and symptoms of hypogonadism. In the treatment group, men (n = 360) received parenteral T undecanoate (TU) 1000 mg/12 weeks following an initial 6-week interval for up to 10 years. Men (n = 296) who had opted against TTh served as controls. Median follow-up in both groups was 7 years. Measurements were taken at least twice a year, and 8-year data were analyzed. Mean changes over time between the 2 groups were compared by means of a mixed-effects model for repeated measures, with a random effect for intercept and fixed effects for time, group, and their interaction. To account for baseline differences between the 2 groups, changes were adjusted for age, weight, waist circumference, fasting glucose, blood pressure, and lipids.

Results:

There were 2 deaths in the T-treated group, none was related to CV events. There were 21 deaths in the untreated (control) group, 19 of which were related to CV events. The incidence of death in 10 patient-years was 0.1145 in the control group (95% confidence interval [CI]: 0.0746-0.1756; P < .000) and 0.0092 in the T-treated group (95% CI: 0.0023-0.0368; P < .000); the estimated difference between groups was 0.0804 (95% CI: 0.0189-0.3431; P < .001). The estimated reduction in mortality for the T-group was between 66% and 92%. There were also 30 nonfatal strokes and 26 nonfatal myocardial infarctions in the control group and none in the T-treated group.

Conclusion:

Long-term TU was well tolerated with excellent adherence suggesting a high level of patient satisfaction. Mortality related to CV disease was significantly reduced in the T-group.

Treatment of Hypogonadism: Current and Future Therapies

The treatment of hypogonadism in men is of great interest to both patients and providers. There are a number of testosterone formulations currently available and several additional formulations under development. In addition, there are some lesser-used alternative therapies for the management of male hypogonadism, which may have advantages for certain patient groups. The future of hypogonadism therapy may lie in the development of selective androgen receptor modulators that allow the benefits of androgens whilst minimizing unwanted side effects.

Improvement of endothelial function following initiation of testosterone replacement therapy

Background

Isolated recent studies have suggested an increased risk of heart attack as early as 3 months following testosterone replacement therapy (TRT). Such a rapid risk increase would likely require rapid deterioration of arterial endothelial function. Our goal was to assess arterial endothelial function in hypogonadal men prior to and at least 3 months after initiation of TRT.

Methods

Adult men were consented if they had symptoms of hypogonadism, a total testosterone <350 ng/dL, and planned to begin TRT. Endothelial function was non-invasively assessed using the EndoPAT-2000 machine. We measured the augmentation index (AI) (normal <3%), a measure of arterial stiffness and reactive hyperemia index (RHI), a measure of endothelial vasodilation (normal >1.69). Prior studies suggest that a 10% level of day-to-day test variability is expected. Endothelial function was reassessed at the next clinic visit, between 3 and 6 months if the patients were compliant with therapy. Changes in continuous variables were assessed with the paired t test.

Results

Twenty-three patients were consented with a mean age of 52.7 years (range, 34–68 years) and starting testosterone 196.9 ng/dL (range, 35–339 ng/dL). There was a history of diabetes in four, hypertension in ten and coronary artery disease in five. Mean RHI was 1.67±0.37 (70% were abnormal) and mean AI was 2.57%±14.0% (39% were abnormal). There were no cardiac events. At follow-up 20 patients were compliant with therapy and retested. Mean testosterone increased from 203 to 511 (P<0.0001). Mean RHI improved from 1.70 to 2.14 (P=0.01). Mean AI improved from 2.9% to −1.75% (P=0.01). In four men RHI worsened but in each case less than the 10% error of the test. No man had worsened AI.

Conclusions

Men with symptomatic hypogonadism often have abnormal arterial endothelial function. Following TRT, endothelial function either remains unchanged or improves.

The consensus recommendations of a group of international experts on the fundamental concepts related to the issues of testosterone deficiency and its treatment

Conference on the development of the international expert consensus to address frequently asked questions related to a medical condition of testosterone deficiency (TD, male hypogonadism) and testosterone therapy was held in Prague (Czech Republic) on October 1, 2015. The included experts were representatives from a variety of medical specialties, including urology, endocrinology, diabetology, internal medicine, as well as representatives of basic medical sciences. An international team of experts came to the following conclusions: TD - an important medical condition that affects the health and well-being of men; TD symptoms is a consequence of low testosterone levels, regardless of whether background etiology installed; TD consequences are global; care must be taken in an attempt to use any uniform threshold levels of testosterone for a decision on the appointment of testosterone therapy; a person does not have any reason to refrain from appointing testosterone therapy only on the basis of age; the existing evidence does not suggest increasing the prostate cancer or cardiovascular disease risk during testosterone therapy; there is evidence conserning the feasibility of a major research initiative to explore possible cardioprotective beneficial effects of testosterone therapy in men with metabolic disorders, including diabetes.

Low Testosterone in Men with Cardiovascular Disease or Risk Factors: To Treat or Not To Treat?

OPINION STATEMENT

Current evidence supports the use of testosterone replacement in men with the clinical-biochemical syndrome of hypogonadism, defined as low testosterone serum levels and symptoms such as fatigue, exercise intolerance, erectile dysfunction, low libido, or depression. Although the evidence consistently shows that hypogonadism is associated with elevated cardiovascular risk, evidence is mixed regarding whether testosterone (T) replacement provides cardiovascular (CV) benefit or harm. For a man with symptomatic hypogonadism in the setting of CV disease, clinical heart failure, and/or traditional CV risk factors (hypertension, diabetes, and hyperlipidemia), a balanced approach would be to counsel him that overall, the evidence should not dissuade him from utilizing T replacement for non-cardiac symptom relief but that more data are needed before a definitive recommendation can be made about T replacement for CV benefit. The preponderance of available evidence, reviewed in this article, suggests that T replacement, at appropriate doses and with monitored response, is likely to be safe for men with CV disease or CV risk factors and may even reduce major adverse cardiovascular events (MACE). The 2015 American Association of Clinical Endocrinologists and American College of Endocrinology position statement supports this stance and calls for improved prospective data. There is a clear need for a large, prospective randomized trial evaluating the impact of T replacement on MACE, for men both with and without CV disease or CV risk factors. Clinicians should be aware that all men who elect to take T replacement therapy require regular follow-up with the prescribing physician to include both clinical assessment and surveillance laboratory assessment of total T level, complete blood count, and prostate specific antigen.

Aging of the endocrine system and its potential impact on sarcopenia

Sarcopenia, occurring as a primary consequence of aging, is a progressive generalized decline of skeletal muscle mass, strength and function. The pathophysiology of sarcopenia is complex and multifactorial. One major cause of muscle mass and strength loss with aging appears to be the alteration in hormonal networks involved in the inflammatory processes, muscle regeneration and protein synthesis. This review describes the recent findings concerning the role of the aging on the endocrine system in the development of sarcopenia. We also report the benefits and safety of hormone replacement therapy in elderly subjects and discuss future perspectives in the therapy and prevention of skeletal muscle aging.

Testosterone treatment is not associated with increased risk of adverse cardiovascular events: results from the Registry of Hypogonadism in Men (RHYME)

AIMS

The aim of this study was to assess cardiovascular (CV) safety of testosterone replacement therapy (TRT) in a large, diverse cohort of European men with hypogonadism (HG).

METHODS

The Registry of Hypogonadism in Men (RHYME) was designed as a multi-national, longitudinal disease registry of men diagnosed with hypogonadism (HG) at 25 clinical sites in six European countries. Data collection included a complete medical history, physical examination, blood sampling and patient questionnaires at multiple study visits over 2-3 years. Independent adjudication was performed on all mortalities and CV outcomes.

RESULTS

Of 999 patients enrolled with clinically diagnosed HG, 750 (75%) initiated some form of TRT. Registry participants, including both treated and untreated patients, contributed 23 900 person-months (99.6% of the targeted) follow-up time. A total of 55 reported CV events occurred in 41 patients. Overall, five patients died of CV-related causes (3 on TRT, 2 untreated) and none of the deaths were adjudicated as treatment-related. The overall CV incidence rate was 1522 per 100 000 person-years. CV event rates for men receiving TRT were not statistically different from untreated men (P=.70). Regardless of treatment assignment, CV event rates were higher in older men and in those with increased CV risk factors or a prior history of CV events.

CONCLUSIONS

Age and prior CV history, not TRT use, were predictors of new-onset CV events in this multi-national, prospective hypogonadism registry.

Pharmacologic Therapy in Men's Health: Hypogonadism, Erectile Dysfunction, and Benign Prostatic Hyperplasia

This article reviews current pharmacologic treatment options for 3 common men's health concerns: hypogonadism, erectile dysfunction (ED), and benign prostatic hyperplasia (BPH). Specific topics addressed include: management of male hypogonadism using testosterone replacement therapy, use of oral phosphodiesterase inhibitors as first-line therapy for men with ED and the utility of intraurethral and intrapenile alprostadil injections for patients who do not respond to oral medications, and the role of alpha1-adrenergic antagonists, 5-alpha-reductase inhibitors, anticholinergic agents, and herbal therapies in the management of BPH.

Fundamental Concepts Regarding Testosterone Deficiency and Treatment: International Expert Consensus Resolutions

To address widespread concerns regarding the medical condition of testosterone (T) deficiency (TD) (male hypogonadism) and its treatment with T therapy, an international expert consensus conference was convened in Prague, Czech Republic, on October 1, 2015. Experts included a broad range of medical specialties including urology, endocrinology, diabetology, internal medicine, and basic science research. A representative from the European Medicines Agency participated in a nonvoting capacity. Nine resolutions were debated, with unanimous approval: (1) TD is a well-established, clinically significant medical condition that negatively affects male sexuality, reproduction, general health, and quality of life; (2) symptoms and signs of TD occur as a result of low levels of T and may benefit from treatment regardless of whether there is an identified underlying etiology; (3) TD is a global public health concern; (4) T therapy for men with TD is effective, rational, and evidence based; (5) there is no T concentration threshold that reliably distinguishes those who will respond to treatment from those who will not; (6) there is no scientific basis for any age-specific recommendations against the use of T therapy in men; (7) the evidence does not support increased risks of cardiovascular events with T therapy; (8) the evidence does not support increased risk of prostate cancer with T therapy; and (9) the evidence supports a major research initiative to explore possible benefits of T therapy for cardiometabolic disease, including diabetes. These resolutions may be considered points of agreement by a broad range of experts based on the best available scientific evidence.

Testosterone Replacement Therapy: The Emperor's New Clothes

The mean age of the world population has steadily increased in the last decades, as a result of increased life expectancy and reduced birth rate. Global aging has led to a greater worldwide cost for healthcare: hormonal alterations contribute to the pathogenesis of several conditions and might cause a significant reduction in the perceived sense of well-being. Menopause is archetypal of hormonal alterations occurring during aging: in males, sex hormones do not decrease abruptly, yet testosterone levels decrease steadily and continuously during aging, ultimately resulting in late-onset hypogonadism. Treatment of this condition might mitigate most symptoms; however, testosterone replacement therapy (TRT) should be prescribed only in selected patients and it should not be considered as an antiaging treatment. In recent years, different authors have questioned health risks associated with testosterone treatment; while position statements from many scientific societies seem to be reassuring, the Food and Drug Administration has issued a warning in regard to the possible side effects of this therapy. We aim to review recent controversies and discoveries in regard to TRT.

Survival and cardiovascular events in men treated with testosterone replacement therapy: an intention-to-treat observational cohort study

BACKGROUND

Conflicting evidence exists for the association between testosterone replacement therapy and mortality and cardiovascular events. The US Food and Drug Administration recently cautioned that testosterone replacement therapy might increase risk of heart attack and stroke, based on evidence from studies with short treatment duration and follow-up. No previous study has assessed the effect of duration of testosterone treatment on these outcomes. We aimed to assess the association between long-term use of testosterone replacement therapy and mortality, cardiovascular events, and prostate cancer diagnoses, using a time-varying exposure analysis.

METHODS

We did a population-based matched cohort study of men aged 66 years or older newly treated with testosterone replacement therapy and controls matched for age, region of residence, comorbidity, diabetes status, and index year from 2007-12 in Ontario, Canada, using data from the Ontario Drug Benefit database, the Canadian Institute for Health Information (CIHI) Discharge Abstract Database, the CIHI National Ambulatory Care Reporting System, the Ontario Health Insurance Plan database, the Ontario Myocardial Infarction Database, the Ontario Diabetes Database, the Ontario Cancer Registry, and the Registered Persons database. We assessed the association between cumulative testosterone replacement therapy exposure and mortality, cardiovascular events, and prostate cancer using marginal models with a time-varying testosterone exposure.

FINDINGS

We included 10 311 men treated with testosterone replacement therapy and 28 029 controls between Jan 1, 2007, and June 30, 2012. Over a median follow-up of 5·3 years (IQR 3·6-7·5) in the testosterone replacement therapy group and 5·1 years (3·4-7·4) in the control group, patients treated with testosterone replacement therapy had lower mortality than did controls (hazard ratio [HR] 0·88, 95% CI 0·84-0·93). Patients in the lowest tertile of testosterone exposure had increased risk of mortality (HR 1·11, 95% CI 1·03-1·20) and cardiovascular events (HR 1·26, 95% CI 1·09-1·46) compared with controls. By contrast, those in the highest tertile of testosterone exposure had decreased risk of mortality (HR 0·67, 95% CI 0·62-0·73) and cardiovascular events (HR 0·84, 95% CI 0·72-0·98), with a significant trend across tertiles (p<0·0001). Risk of prostate cancer diagnosis was decreased for those with the highest tertile of exposure (HR 0·60, 95% CI 0·45-0·80) compared with controls, but not for those with the shortest exposure.

INTERPRETATION

Long-term exposure to testosterone replacement therapy was associated with reduced risks of mortality, cardiovascular events, and prostate cancer. However, testosterone replacement therapy increased the risk of mortality and cardiovascular events with short durations of therapy. In view of the limitations of observational data and the potential for selection bias, these results warrant confirmation in a randomised trial.

FUNDING

Physicians' Services Incorporated Foundation and Ajmera Family Chair in Urologic Oncology.

Testosterone deficiency in the aging male

Treatment for hypogonadism is on the rise, particularly in the aging population. Yet treatment in this population represents a unique challenge to clinicians. The physiology of normal aging is complex and often shares the same, often vague, symptoms of hypogonadism. In older men, a highly prevalent burden of comorbid medical conditions and polypharmacy complicates the differentiation of signs and symptoms of hypogonadism from those of normal aging, yet this differentiation is essential to the diagnosis of hypogonadism. Even in older patients with unequivocally symptomatic hypogonadism, the clinician must navigate the potential benefits and risks of treatment that are not clearly defined in older men. More recently, a greater awareness of the potential risks associated with treatment in older men, particularly in regard to cardiovascular risk and mortality, have been appreciated with recent changes in the US Food and Drug Administration recommendations for use of testosterone in aging men. The aim of this review is to provide a framework for the clinician evaluating testosterone deficiency in older men in order to identify correctly and treat clinically significant hypogonadism in this unique population while minimizing treatment-associated harm.

The "Choosing Wisely" initiative to reduce low value care: has endocrinology been wise enough?

The challenges of practicing medicine manifest at multiple levels from the clinician-patient interaction to society. Among these are excess health care costs related to overuse and use of low-value care, services which do not provide benefits worth the cost. Physicians have a role as stewards of finite resources. The Choosing Wisely initiative seeks to address this issue and involves multiple professional societies. We describe the recommendations of the Endocrine Society and others as they apply to the practicing endocrinologist.

Testosterone Replacement Therapy and Cardiovascular Risk: A Review

Recent reports in the scientific and lay press have suggested that testosterone (T) replacement therapy (TRT) is likely to increase cardiovascular (CV) risk. In a final report released in 2015, the Food and Drug Administration (FDA) cautioned that prescribing T products is approved only for men who have low T levels due to primary or secondary hypogonadism resulting from problems within the testis, pituitary, or hypothalamus (e.g., genetic problems or damage from surgery, chemotherapy, or infection). In this report, the FDA emphasized that the benefits and safety of T medications have not been established for the treatment of low T levels due to aging, even if a man's symptoms seem to be related to low T. In this paper, we reviewed the available evidence on the association between TRT and CV risk. In particular, data from randomized controlled studies and information derived from observational and pharmacoepidemiological investigations were scrutinized. The data meta-analyzed here do not support any causal role between TRT and adverse CV events. This is especially true when hypogonadism is properly diagnosed and replacement therapy is correctly performed. Elevated hematocrit represents the most common adverse event related to TRT. Hence, it is important to monitor hematocrit at regular intervals in T-treated subjects in order to avoid potentially serious adverse events.