Testosterone Replacement Therapy and Cardiovascular Risk: A Review

Evaluating the impact of testosterone replacement therapy on carotid atherosclerosis: a systematic review and meta-analysis

Aim: This meta-analysis investigates the association between testosterone replacement therapy [TRT] and carotid artery atherosclerosis. Methods: 3 databases were searched for studies up to June 2023 per the PRISMA guidelines. The eligibility criteria comprised RCTs and observational studies involving hypogonadal males receiving exogenous testosterone, in which CIMT was assessed. CAA was the primary outcome, whereas secondary outcomes included HDL, LDL, CRP, total cholesterol and total testosterone. The statistical analysis was performed using Review Manager. Results: Statistical analysis revealed no association between TRT and assessed outcomes. There was a significant increase in total testosterone levels, depicting indirect anti-atherosclerotic effects of TRT. Conclusion: Meta-analysis shows no relation between TRT and CIMT or other markers, allowing its safe usage for hypogonadal males.

Testosterone Replacement Therapy in Relation With Cardiovascular Disease in Cisgender Women and Transgender People

AIMS

This study aimed to investigate the association of testosterone replacement therapy (TTh) with risk of cardiovascular disease (CVD), and CVD-specific outcomes, in cisgender women and transgender population, and to determine whether this association varies by menopausal status.

METHODS

In 25 796 cisgender women and 1580 transgender people (≥30 years old) who were enrolled in the Optum's deidentified Clinformatics Data Mart Database (2007-2021), we identified 6288 pre- and postmenopausal cisgender women and 262 transgender people diagnosed with incident composite of CVD (coronary artery disease [CAD], congestive heart failure, stroke, and myocardial infarction). Prediagnostic prescription of TTh was ascertained for this analysis. Multivariable adjusted Cox proportional hazards models were used to examine the independent association of TTh with incident CVD.

RESULTS

We found a 24% increased risk of CVD (hazard ratio [HR] = 1.24; 95% CI, 1.15-1.34), 26% risk of CAD (HR = 1.26; 95% CI, 1.14-1.39), and a 29% risk of stroke (HR = 1.29; 95% CI, 1.14-1.45) after comparing cisgender women who used TTh with nonusers. Stratification by age group showed similar effects of TTh on CVD, CAD, and stroke. Among transgender people, TTh did not increase the risk of composite CVD, including by age stratification.

CONCLUSION

Use of TTh increased the risk of CVD, CAD, and stroke among cisgender women but not among transgender people. TTh is becoming more widely accepted in women, and it is the main medical treatment for transgender males. Therefore, use of TTh should be further investigated for the prevention of CVD.

Developments and challenges for new and emergent preparations for male hypogonadism treatment

INTRODUCTION

The specific role of testosterone (T) replacement therapy in patients with late onset hypogonadism is still conflicting. Several available preparations have been developed to restore either fertility and normal testosterone (T) levels (secondary hypogonadism) or just T levels (primary hypogonadism).

AREAS COVERED

Advantages and limitations related to available new treatments will be discussed in detail. In addition, possible news related to preparations in the pipeline will be discussed.

EXPERT OPINION

The selection of a specific T preparation should be adequately discussed with each subject. Transdermal T preparations are those that can preserve, after a unique morning administration, the circadian rhythmicity of T secretion. Conversely, short-acting preparations (such as oral or intranasal) need two- or three-times daily administration, potentially reducing patient compliance. Long acting T preparations, such as injectable T undecanoate have the advantage of bimestrial or trimestral administration, reducing the required number of administrations. The use of non-steroidal selective androgen receptor modulators (SARM), a heterogeneous class of compounds selectively acting on androgen receptor targets, remains investigational due to the lack of the full spectrum of T's action and the possible risk of side effects, despite their potential use in the treatment of muscle wasting and osteoporosis.

Novel androgen therapies including selective androgen receptor modulators

Male hypogonadism is associated with reduced quality of life and the development of co-morbidities including obesity, diabetes mellitus, and dyslipidaemia. The mainstay of treatment for male hypogonadism is testosterone replacement therapy (TRT). However, TRT has recognised side effects including impaired spermatogenesis and there are concerns regarding its use in men with concurrent cardiovascular disease. Thus, there has been an impetus to develop novel androgen therapies for treating male hypogonadism to mitigate the side effects of TRT. This review will discuss the benefits and adverse effects of TRT, and novel therapies including nasal testosterone, aromatase inhibitors, selective oestrogen receptor modulators, and selective androgen receptor modulators.

Testosterone protects cardiomyocytes against hydrogen peroxide-induced aging by upregulating IGF1 and SIRT1 pathways

Objective

To investigate the role of IGF1 and SIRT1 pathways in protection of hydrogen peroxide (H2O2)-induced aging in H9c2 rat cardiomyocyte cells by testosterone.

Methods

The cells were treated with testosterone or up- or down-regulated for the IGF1 and SIRT1 genes and assessed for apoptosis, aging and expression of relevant genes.

Results

Aging was induced and the expression of SIRT1 and IGF1 was down-regulated after H2O2 treatment in H9c2 cells. The aging was attenuated in a dose-dependent manner after the cells were exposed to testosterone. Down-regulation of SIRT1 and IGF1expression was offset in the H2O2-treated cells co-treated with testosterone. Up- or down-regulation of IGF1 significantly reduced or increased senescence-associated beta-galactosidase (SA-β-gal) cells and the ROS level, respectively. In addition, SIRT1 expression was regulated by IGF1 expression. Down- or up-regulation of SIRT1 significantly decreased or increased the IGF1 levels, respectively. Furthermore, after IGF1 and SIRT1 knockdown, testosterone did not protect the cells from senescence. Testosterone, and overexpression of IGF1 and SIRT1 also up-regulated the expression of the fetal genes SERCA2 and MYH6 and down-regulated the expression of the ACTA1 and MYH7 genes.

Conclusions

Our data indicate that testosterone can attenuate cardiomyocyte aging induced by H2O2 and up-regulate SIRT1 and IGF1. The IGF1and SIRT1 pathway may be new targets to treat heart aging and heart failure.

Morbidity and mortality in men: Role of androgens

In this narrative review we provide an overview of the current literature on male hypogonadism and related comorbidities, also depicting the role of testosterone therapy (TTh) in the various settings. Male hypogonadism has been associated with major comorbidities such as type 2 diabetes mellitus, obesity and cardiovascular diseases, promoting a vicious cycle that may lead to further hypogonadism. The biological underpinnings of this association are currently under investigations, but clearly emerges the relevance of the hypothalamic-pituitary-gonadal axis. Hypogonadism has also been associated with increased risk of mortality. As such, TTh has the potential to oppose these patterns and improve cardiovascular and metabolic health in hypogonadal men. Clinical and observational data suggest that in males with hypogonadism, TTh, together with lifestyle changes and diabetes medications, may improve glycemia, reduce risk of progression to diabetes and provides positive effects on cardiovascular risk. Conversely, available data does not fully support any increased risk of prostate cancer in men under TTh. Of clinical relevance, a possible harmful role of hypogonadal status in men with COVID-19 eventually emerged.

Testosterone deficiency and the risk of anemia: A propensity score-matched analysis

OBJECTIVE

There are little data on the endogenous testosterone effect on hemoglobin or hematocrit. Moreover, these data are limited by a cross-sectional study design, a small participant number, and no adjustment for confounding factors. Therefore, the present study was conducted to address the aforementioned limitations of previous studies using a large dataset and propensity score matched analysis.

MATERIALS AND METHODS

Men who underwent health check-up were analyzed. Participants were divided into two groups using the cut-off testosterone value of 3.5 or 3.0 ng/ml according to a previous definition of testosterone deficiency. Using the cutoff testosterone value of 3.5 ng/ml, 966 cases (testosterone levels <3.5 ng/ml) and 7402 controls (testosterone level ≥3.5 ng/ml) were included, but following propensity score matching, there were 966 cases and 1932 controls. Using the cutoff testosterone value of 3.0 ng/ml, 444 cases (testosterone levels <3.0 ng/ml) and 7924 controls (testosterone level ≥3.0 ng/ml) were included, but following propensity score matching, there were 444 cases and 888 controls.

RESULTS

After matching, the groups were evenly distributed with respect to age, body mass index, estimated glomerular filtration rate, hypertension, and diabetes in both data sets. After matching, the mean Hb and Hct were significantly lower and the incidence of anemia was significantly greater in the case compared to the control in both data sets. The relative risk of anemia in the case was 2.4 compared to the control in both data sets.

CONCLUSION

Screening for anemia in patients with testosterone deficiency would be needed and vice versa.

Energy Metabolism Focused Analysis of Sexual Dimorphism in Biological Aging and Hypothesized Sex-specificity in Sirtuin Dependency

The process of biological aging or senescence refers to the gradual loss of homeostasis and subsequent loss of function - leading to higher chances of mortality. Many mechanisms and driving forces have been suggested to facilitate the evolution of a molecular circuit acting as a trade-off between survival and proliferation, resulting in senescence. A major observation on biological aging and longevity in humans and model organisms is the prevalence of significant sexual divergence in the onset, mechanisms and effects of aging associated processes. In the current account, we describe possible mechanisms by which aging, sex and reproduction are evolutionarily intertwined in order to maintain systemic energy homeostasis. We also interrogate existing literature on the sexual dimorphism of genetic, cellular, metabolic, endocrine and epigenetic processes driving cellular and systemic aging. Subsequently, based on available evidence, we propose a hypothetic model of sex-limited decoupling of female longevity from sirtuins, a major family of regulator proteins of the survival-proliferation trade-off. We also provide necessary considerations to be made in order to test the hypothesis and explore the physiological and therapeutic implications of this decoupling event in male and female longevity after reaching reproductive maturity. HYPOTHESIS STATEMENT: Sirtuins provide survival benefits in a sex-nonspecific manner but the dependency on sirtuins in driving metabolic networks after reaching reproductive maturity is evolutionarily decoupled from female longevity.

The Role of testosterone treatment in patients with metabolic disorders

INTRODUCTION

The specific role of testosterone [T] replacement therapy [TRT] on glycometabolic profile and body composition, particularly in patients with metabolic syndrome [MetS] and/or type 2 diabetes mellitus [T2DM], is still the object of an intense debate.

AREAS COVERED

To discuss available evidence on the association between T and metabolic diseases and on the possible effect of T administration on metabolic disorder-associated hypogonadism. Both preclinical and clinical data have been considered. In addition, a meta-analysis of the available placebo and non-placebo-controlled randomized clinical trials [RCTs] investigating the effects of TRT in T2DM or MetS in several outcomes has been also performed.

EXPERT OPINION

Data derived from preclinical and clinical studies suggest that T administration, by reducing fat mass, can improve body composition and ameliorate some aspects of glucose metabolism. The effects of TRT on sexual function in patients with established metabolic derangements are inconsistent, whereas better results were observed in preclinical conditions or in patients with newly diagnosed T2DM.

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.

Reflections on the T Trials

BACKGROUND

This manuscript is a review and discussion of the published results of the T Trials.

OBJECTIVE

To re-examine the efficacy of testosterone replacement of hypogonadal men >65 years of age in the T Trials.

MATERIALS AND METHODS

The T Trials were a complex collection of seven double blind, placebo-controlled trials of the efficacy of testosterone as replacement therapy for older men with unequivocal hypogonadism. There were three main trials (sexual function; physical function; vitality) and four sub-trials (cognition; bone; anemia; and cardiovascular). All subjects participated in the main trials while more selective inclusion/exclusion criteria existed for the sub-trials. Subjects were excluded for perceived higher risk of prostate cancer and recent myocardial or cerebral vascular events.

RESULTS

The previously published results are reviewed here as seen in the context of this special issue on late-onset hypogonadism. In the T Trials, positive benefits were seen in the sexual function, bone, and anemia trials with small but significant benefits in the vitality trial. No benefit was seen in the cognition trial, partial benefit in physical function, and a negative benefit outcome seen in the cardiovascular trial. The later trial was underpowered and the results were described as exploratory. Adverse events were relatively uncommon in the 12-month treatment phase and additional 12-month post-treatment phase. The most frequent adverse effect ascribed to testosterone was erythrocytosis.

CONCLUSIONS

The T Trials studied the efficacy of testosterone replacement therapy on 788 men with low testosterone and symptoms of hypogonadism. The studies demonstrated benefits in four trials (sexual function, vitality, bone, and anemia); partial benefit in the physical function trial; no effect in the cognition trial; and a negative effect in the exploratory cardiovascular trial. The T Trials were not designed to assess long-term risks of testosterone in men.

Therapeutic Phlebotomy for Testosterone-Induced Polycythemia

OBJECTIVES

To evaluate therapeutic phlebotomy (TP) requests for testosterone replacement therapy (TRT) and to highlight the impact to a blood center (BC) or service that provides TP for individuals on TRT.

METHODS

Review of TP requests for individuals on TRT at our BC over a 3-year period from 2014 through 2016, as well as the total number of TP collections.

RESULTS

Total TPs during 2014, 2015, and 2016 were 475, 500, and 569, respectively. Annual TP collections for patients on TRT were 193, 212, and 239, respectively. TRT patients with TP orders increased 71.4% during this period. After discontinuation of TP services for TRT at our BC, 32% continued to donate as volunteer blood donors at our BC.

CONCLUSIONS

Our BC observed increased TP requests for patients on TRT from 2014 through 2016. Our findings suggest that individuals on TRT may be presenting to BCs as volunteer blood donors to avoid charges for TP.

Approaches to male hypogonadism in primary care

Evidence suggests that providers are not adhering to current testosterone replacement therapy guidelines when treating male hypogonadism. Understanding the diagnosis and management of this condition is further complicated by conflicting recommendations among available guidelines. NPs must select and follow the best guideline recommendations available to optimally treat male hypogonadism.

Evidence suggests that providers are not adhering to current testosterone replacement therapy guidelines when treating male hypogonadism. Understanding diagnosis and management is further complicated by conflicting recommendations among available guidelines. NPs must select and follow the best guideline recommendations available to optimally treat this condition.

Investigating the basis of sexual dysfunction during late-onset hypogonadism

Late-onset hypogonadism (LOH) is the term used to describe the decline in serum testosterone levels associated with increasing age in men above 40 years. A number of symptoms are attributed to LOH, but the most common association is that of sexual dysfunction. LOH has recently come under greater scrutiny with the widespread use of testosterone therapy, and concerns regarding the efficacy and safety of testosterone replacement therapy have been raised. In particular, the cardiovascular safety and the beneficial effects of testosterone replacement therapy on general health have been questioned. This review will give an overview of the current evidence for the relationship of LOH and male sexual dysfunction.

To T or not to T: Differences in Testosterone Use and Discontinuation by HIV Serostatus among Men who Have Sex with Men

OBJECTIVES

The aim of the study was to characterize contemporary patterns and correlates of testosterone therapy (TTh) use and discontinuation by HIV serostatus among men in the Multicenter AIDS Cohort Study (MACS).

METHODS

Self-reported testosterone use data were collected semiannually from 2400 (1286 HIV-infected and 1114 HIV-uninfected) men who have sex with men. Multivariable Poisson regression was used to estimate prevalence ratios for TTh use and predictors of TTh discontinuation (2012-2015).

RESULTS

Use was higher among HIV-infected compared with HIV-uninfected men in all age strata, with an age-adjusted prevalence of 17% vs. 5%, respectively (adjusted prevalence ratio 3.7; P < 0.001). Correlates of use in the multivariable model were similar by HIV serostatus: white race, the Los Angeles (LA) site, more than one recent sexual partner, non-smoking status, and higher American Heart Association/American College of Cardiology (AHA/ACC) cardiovascular disease (CVD) risk score category (approximately 70% of testosterone users were in the high-risk category). Compared with HIV-uninfected men, HIV-infected men more frequently reported building muscle mass as a motivation for testosterone use. The TTh discontinuation rate was 20.9/100 person-years [95% confidence interval (CI) 17.3, 25.0/100 person-years]. Relative to HIV-uninfected men, HIV-infected men were half as likely to discontinue (adjusted incidence rate ratio 0.4; P < 0.001). Discontinuation was 40% higher in the period after the US Food and Drug Administration (FDA) safety communication for testosterone in 2014, independent of co-factors (P = 0.06).

CONCLUSIONS

Given the high prevalence of both TTh use and CVD risk among HIV-infected men, the benefits and risks of TTh should be examined in future studies of aging HIV-infected men and monitored routinely in clinical practice.

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.

Transdermal Testosterone in Female Hypoactive Sexual Desire Disorder: A Rapid Qualitative Systematic Review Using Grading of Recommendations Assessment, Development and Evaluation

Female hypoactive sexual desire disorder (HSDD) is a multifactorial sexual dysfunction disorder characterized by a decrease in sexual desire and personal distress. HSDD occurs in naturally occurring postmenopausal women or secondary to oophorectomy. Multiple studies have assessed the use of transdermal testosterone (TDT) as a management option for patients with HSDD. Our aim is to assess published studies using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework for the quality of evidence regarding testosterone use as a short- and long-term therapy for HSDD. We implemented this qualitative systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. We set a GRADE score of 4 (high evidence) as a cutoff point for the quality measure of published studies assessing the use of TDT in HSDD. The outcomes of interest were the efficacy of TDT on the total number of satisfying sexual activity, number of orgasms, sexual desire and distress level in patients with HSDD. These outcomes were evaluated through Sexual Activity Log (SAL), Profile of Female Sexual Function (PFSF), and Personal Distress Scale (PDS) evaluation tools. Five randomized controlled trials were identified to meet the inclusion criteria. The selected studies were of high evidence based on the GRADE score as two of the studies scored 4 points, the other two studies scored 5 points and one study scored 6 points. All of the high quality selected studies had similar outcomes suggesting high effectiveness for the use of 300 µg/d TDT with or without estrogen for the management of HSDD with minimal side effects. One study showed a trend for higher risk of breast cancer in long-term use (0.37%). The use of 300 µg/d of TDT in surgical and natural menopause is an effective plan to manage HSDD in the short- and long-term. Although side effects are minimal, further prospective research is needed to assess the more severe side effects such as breast cancer in the long-term use of TDT.

The safety of available treatments of male hypogonadism in organic and functional hypogonadism

INTRODUCTION

In the case of primary male hypogonadism (HG), only testosterone (T) replacement therapy (TRT) is possible whereas when the problem is secondary to a pituitary or hypothalamus alteration both T production and fertility can be, theoretically, restored. We here systematically reviewed and discussed the advantages and limits of medications formally approved for the treatment of HG.

AREAS COVERED

Data derived from available meta-analyses of placebo controlled randomized trials (RCTs) were considered and analyzed. Gonadotropins are well-toleratedand their use is mainly limited by higher costs and a more cumbersome treatment schedule than TRT. Available RCTs on TRT suggest that cardiovascular (CV) and venous thromboembolism risk is not a major issue and that prostate safety is guaranteed. The risk of increased hematocrit is mainly limited to the use of short terminjectable preparations.

EXPERT OPINION

In the last few years the concept of 'organic' irreversible HG and 'functional' or age- and comorbidity-related HG has been introduced. This definition is not evidence-based. The majority of RCTs enrolled patients with 'functional' HG. Considering the significant improvement in body composition, glucose metabolism and sexual activity, TRT should not be limited to 'organic' HG, but also offered for 'functional'.

Effect of testosterone supplementation on nitroso-redox imbalance, cardiac metabolism markers, and S100 proteins expression in the heart of castrated male rats

The aim of this study was to investigate the effects of castration and testosterone supplementation on nitroso-redox status, cardiac metabolism markers, and S100 proteins expression in the heart of male rats. 50 male Wistar rats were randomized into five groups with ten animals each: group 1: control intact (CON); group 2: sham operated (Sh-O); group 3: sesame oil-treated rats (S-oil); group 4: gonadoectomized (GDX); and group 5: gonadoectomized rats treated with testosterone (GDX-T) for 8 weeks. Our results showed myofibrillar weaving, apoptosis, inflammation, and fibrosis (as reflected by increased activity of MMP 9 and MMP 2) in the heart of gonadoectomized rats. Testosterone supplementation restored the normal structure of the heart. In addition, a state of nitroso-redox imbalance was observed in the heart of castrated rats with increased NO (425.1 ± 322.8 vs. 208 ± 67.06, p ˂ 0.05) and MDA (33.18 ± 9.45 vs. 22.04 ± 7.13, p ˂ 0.05) and decreased GSH levels (0.71 ± 0.13 vs. 1.09 ± 0.19, p = 0.001). Testosterone treatment leads to a re-establish of only NO levels (425.1 ± 322.8 vs. 210.4 ± 114.3, p > 0.05). Markers of cardiac metabolism showed an enhancement of LDH activity (12725 ± 4604 vs. 5381 ± 3122, p ˂ 0.05) in the heart of castrated rats. This was inversed by testosterone replacement (12725 ± 4604 vs. 5781 ± 5187, p ˂ 0.05). Furthermore, castration induced heart's accumulation of triglycerides (37.24 ± 6.17 vs. 27.88 ± 6.47, p ˂ 0.05) and total cholesterol (61.44 ± 3.59 vs. 54.11 ± 7.55, p ˂ 0.05), which were significantly reduced by testosterone supplementation (29.03 ± 2.47 vs. 37.24 ± 6.17, p ˂ 0.05) and (47.9 ± 4.15 vs. 61.44 ± 3.59, p ˂ 0.001). Cardiomyocytes of castrated rats showed a decreased immunoexpression of S100 proteins compared to control animals. A restoration of S100 proteins immunostaining in cardiomyocyte cytoplasm was observed after testosterone supplementation. These findings confirm the deleterious effects of testosterone deficiency on cardiac function and highlight the involvement of nitric oxide, metalloproteinases 2 and 9, and S100 proteins.

Testosterone replacement therapy and the risk of stroke in men: A systematic review

In recent years, questions have been raised regarding the cardiovascular safety of testosterone replacement therapy (TRT). The objective of this study was to systematically review the available evidence on TRT safety in men, specifically with respect to the risk of stroke. We identified publications from MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials up to May 2017. Articles eligible for review included observational studies evaluating TRT and the risk of stroke among men aged 18 or older. Randomized controlled trials (RCTs) comparing testosterone to placebo in men were also eligible, provided stroke was identified as an adverse event. Among seven cohort studies of hypogonadal men, one study reported that TRT was associated with a significant decrease in the risk of ischemic stroke (hazard ratio (HR) 0.64; 95% confidence interval (CI) 0.52-0.80). Another reported a similar decrease in risk (HR 0.64; 95% CI 0.43-0.96) among treated men who achieved normalized levels of testosterone. Limitations in study design, including immortal time bias and residual confounding, may have influenced both of these results. The remaining observational studies did not report measures of association to estimate the independent risk of stroke associated with TRT. Among eight RCTs, a low frequency of stroke events (<5) was observed across both testosterone and control groups, thus precluding any definitive conclusions. Based on these findings, the association between TRT and the risk of stroke in men remains unclear, and further large and methodologically robust studies are needed to establish this relationship.

Testosterone treatment and cardiovascular and venous thromboembolism risk: what is 'new'?

In men, testosterone (T) production declines as a function of ageing. Late-onset hypogonadism (LOH) is the most commonly used term to indicate this age-related condition. In LOH, the relative clinical significance and the potential benefit of testosterone treatment (TTh) are still the subject of strong criticisms in the scientific community. The debate is further complicated by the recent position statement of the US Food and Drug Administration (FDA) emphasizing that, in LOH, the benefits and safety of TTh have not been fully established. Hence, the FDA required a labeling change to inform patients about a possible increased cardiovascular (CV) risk of TTh. Similar considerations were previously released by the FDA and by Health Canada concerning a TTh-related venous thromboembolism (VTE) risk. In this review, we will summarize the available evidence concerning a possible link among TTh and CV and VTE risks. For this purpose, data derived from epidemiological studies analyzing relationships between the aforementioned risks and endogenous T levels will be analyzed. In addition, evidence deriving from interventional studies including pharmacoepidemiological and placebo-controlled randomized controlled trials (RCTs) will be examined. Our analysis shows that available data do not support an increased CV risk related to TTh. Similar considerations can be drawn for the relationship between TTh and VTE. The previously reported cases of TTh-related VTE were frequently related to a previously undiagnosed thrombophilia-hypofibrinolysis status. Hence, an anamnestic screening for thrombophilia before starting TTh is recommended, just as it is for the use of oral contraceptives.

Testosterone Replacement Therapy: Long-Term Safety and Efficacy

Recent position statements and guidelines have raised the distinction between a true and false, age-related hypogonadism (HG) or late-onset hypogonadism (LOH). The former is the consequence of congenital or acquired “organic” damage of the brain centers or of the testis. The latter is mainly secondary to age-related comorbidities and does not require testosterone (T) therapy (TTh). In addition, concerns related to cardiovascular (CV) safety have further increased the scepticism related to TTh. In this paper, we reviewed the available evidence supporting the efficacy of TTh in non-organic HG and its long term safety. A large amount of evidence has documented that sexual symptoms are the most specific correlates of T deficiency. TTh is able to improve all aspects of sexual function independent of the pathogenetic origin of the disease supporting the scientific demonstration that LOH does exist according to an “ex-juvantibus” criterion. Although the presence of metabolic derangements could mitigate the efficacy of TTh on erectile dysfunction, the positive effect of TTh on body composition and insulin sensitivity might counterbalance the lower efficacy. CV safety concerns related to TTh are essentially based on a limited number of observational and randomized controlled trials which present important methodological flaws. When HG is properly diagnosed and TTh correctly performed no CV and prostate risk have been documented.

Gaps in Patient Knowledge About Risks and Benefits of Testosterone Replacement Therapy

OBJECTIVE

To assess patient knowledge of the symptoms of testosterone deficiency, and the benefits and risks associated with testosterone replacement therapy (TRT).

METHODS

An anonymous, 10-question multiple choice survey was administered to consecutive patients presenting for urologic evaluation at an academic medical center, from December 2015 to April 2016. The survey included questions about perceived symptoms of testosterone deficiency, perceived benefits and risks associated with TRT, whether respondents had a diagnosis of testosterone deficiency, and whether they were interested in receiving TRT.

RESULTS

The survey response rate was 88% (97/110). The median age group was 41-50 years. Although 43% of all respondents reported an interest in TRT, only half of them had a clinical diagnosis of hypogonadism. The most commonly reported symptoms of low testosterone were "low energy" (54%), "decreased libido" (51%), "weak erections" (52%), and "decreased strength" (42%). Of the perceived benefits of TRT, the most commonly reported were "improved sexual function" (54%), "increased energy" (53%), and "feeling better" (51%). Half of the respondents were unsure of the risks of TRT. Of the respondents, 16%, 10%, and 8% acknowledged the association between TRT and heart attack, TRT and stroke, and TRT and blood clots, respectively.

CONCLUSION

There is disproportionate knowledge about the benefits vs the risks associated with TRT among patients. Although 43% of the respondents were interested in receiving TRT, half of the respondents were unsure of the associated risks. These findings indicate an ongoing need for patient education regarding TRT.

Testosterone replacement therapy and the heart: friend, foe or bystander?

The role of testosterone therapy (TTh) in cardiovascular disease (CVD) outcomes is still controversial, and it seems will remain inconclusive for the moment. An extensive body of literature has investigated the association of endogenous testosterone and use of TTh with CVD events including several meta-analyses. In some instances, a number of studies reported beneficial effects of TTh on CVD events and in other instances the body of literature reported detrimental effects or no effects at all. Yet, no review article has scrutinized this body of literature using the magnitude of associations and statistical significance reported from this relationship. We critically reviewed the previous and emerging body of literature that investigated the association of endogenous testosterone and use of TTh with CVD events (only fatal and nonfatal). These studies were divided into three groups, “beneficial (friendly use)”, “detrimental (foe)” and “no effects at all (bystander)”, based on their magnitude of associations and statistical significance from original research studies and meta-analyses of epidemiological studies and of randomized controlled trials (RCT’s). In this review article, the studies reporting a significant association of high levels of testosterone with a reduced risk of CVD events in original prospective studies and meta-analyses of cross-sectional and prospective studies seems to be more consistent. However, the number of meta-analyses of RCT’s does not provide a clear picture after we divided it into the beneficial, detrimental or no effects all groups using their magnitudes of association and statistical significance. From this review, we suggest that we need a study or number of studies that have the adequate power, epidemiological, and clinical data to provide a definitive conclusion on whether the effect of TTh on the natural history of CVD is real or not.

A Comparison of Secondary Polycythemia in Hypogonadal Men Treated with Clomiphene Citrate versus Testosterone Replacement: A Multi-Institutional Study

PURPOSE

We evaluated the relative prevalence of secondary polycythemia in hypogonadal men treated with clomiphene citrate or testosterone replacement therapy.

MATERIALS AND METHODS

In this retrospective, multi-institutional study, we included 188 men who received clomiphene citrate and 175 who received testosterone replacement therapy with symptomatic hypogonadism. The overall prevalence and ORs of secondary polycythemia for clomiphene citrate treatment vs testosterone replacement were primarily measured, as were baseline characteristics. Subset analysis included polycythemia rates for different types of testosterone replacement therapy.

RESULTS

Overall, men on testosterone replacement therapy were older than clomiphene citrate treated men (age 51.5 vs 38 years). Men on testosterone replacement had longer treatment duration than clomiphene citrate treated men (19.6 vs 9.2 months). For testosterone replacement therapy and clomiphene citrate the mean change in hematocrit was 3.0% and 0.6%, and the mean change in serum testosterone was 333.1 and 367.6 ng/dl, respectively. The prevalence of polycythemia in men on testosterone replacement was 11.2% vs 1.7% in men on clomiphene citrate (p = 0.0003). This significance remained on logistic regression after correcting for age, site, smoking history and pretreatment hematocrit.

CONCLUSIONS

The prevalence of polycythemia in men treated with clomiphene citrate was markedly lower than that in men on testosterone replacement therapy. The improvement in absolute serum testosterone levels was similar to that in men on testosterone replacement. There is no significant risk of polycythemia in men treated with clomiphene citrate for hypogonadism.

Testosterone Replacement-Freedom From Symptoms or Hormonal Shackles?

INTRODUCTION

The question of whether to initiate men on testosterone replacement therapy (TRT) and for how long remains a relevant question to be answered.

AIM

To determine when to start patients on TRT, determine the benefits of TRT, and whether starting patients on TRT condemns them to a lifetime of hormonal replacement.

METHODS

A literature review of relevant publications in PubMed was used.

MAIN OUTCOME MEASURES

Main outcome measures were evidence for initiating TRT, benefits of TRT, pathophysiology of TRT, and evidence for duration of TRT.

RESULTS

Although the exact threshold of serum testosterone levels that define hypogonadism is still strongly debated, the presence of symptoms associated with low levels of testosterone can be considered to help make the diagnosis. Although the proper duration of TRT has yet to be established, maintenance of symptom improvement after discontinuing TRT has been observed, which is a promising result. Studies also have shown a return to hormonal baseline after discontinuation of TRT.

CONCLUSION

It has been established that patients with testosterone deficiency benefit from TRT. Preliminary evidence seems to show that men who are initiated on TRT are not condemned to a lifetime of hormonal therapy, although many men might choose to continue treatment because of improvement in their symptoms.

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.