Low testosterone level as a predictor of cardiovascular events in Japanese men with coronary risk factors

Testosterone and aging male, a perspective from a developing country

PURPOSE

Hypogonadism is associated with a wide range of physical and psychological symptoms that can affect the overall health of men. However, in a developing country, there are several imposing challenges in the diagnosis and treatment of hypogonadism, including a lack of awareness and understanding of the condition among healthcare providers and patients, limited resources and the high cost of treatment. This review aimed to examine the potential benefits and risks of testosterone replacement therapy (TRT) and provides a perspective of a developing country on the topic.

MATERIALS AND METHODS

A comprehensive literature review was conducted to gather relevant information on the impact of testosterone deficiency on ageing males and the effectiveness of TRT for treating hypogonadism. Published peer-reviewed articles were analyzed to evaluate the benefits and risks of TRT. Additionally, the unique challenges faced in the diagnosis and treatment of hypogonadism in a developing country were considered.

RESULTS

Testosterone replacement therapy has been shown to be an effective treatment for hypogonadism, particularly in symptomatic men with low testosterone levels. It offers potential benefits such as improvements in symptoms and overall quality of life. However, there are associated risks and side effects that need to be considered. In a developing country, challenges such as limited awareness and understanding of hypogonadism, resource constraints, and high treatment costs pose additional barriers to accessing TRT and comprehensive care.

CONCLUSION

In conclusion, TRT holds promise as a treatment for hypogonadism, but its implementation and accessibility face significant challenges in a developing country. Addressing these challenges, including raising awareness, allocating resources, and finding cost-effective solutions, is crucial for ensuring that men with hypogonadism in such settings receive appropriate diagnosis and treatment. Further research and efforts are needed to improve the management of hypogonadism in developing countries and optimize the potential benefits of TRT for affected individuals.

Major cardiovascular disease risk in men with testosterone deficiency (hypogonadism): appraisal of short, medium and long-term testosterone therapy - a narrative review

INTRODUCTION

Low testosterone (T) levels are associated with obesity, metabolic syndrome, type 2 diabetes mellitus and altered lipid profiles, thus contributing to increased cardiovascular disease risk. Hence T deficiency has a detrimental effect on men's vascular health, quality of life and increased mortality.

OBJECTIVES

This review aims to present summary of data in the contemporary clinical literature pertaining to the benefits of T therapy in clinical studies with varying durations on vascular health in men with T deficiency.

METHODS

A Medline search using PubMed and EMBASE was performed using the following key words: "testosterone deficiency," "testosterone therapy," major cardiovascular adverse events", "cardiovascular disease". Relevant studies were extracted, evaluated, and analyzed. We evaluated findings from clinical trials, observational studies and systematic reviews and meta-analyses to develop a comprehensive account of the critical role of T in maintaining vascular health.

RESULTS

Considerable evidence beginning with studies published in 1940s concomitant with findings from the utmost recent clinical studies suggests a clinical value of T therapy in maintaining vascular health and reducing cardiovascular mortality. The current scientific and clinical evidence demonstrates strong relationship between low circulating T levels and risk of cardiovascular disease and T therapy is deemed safe in men with hypogonadism when given in the physiological range with no apparent harm.

CONCLUSION

What emerges from the current clinical literature is that, irrespective of the length of study durations, testosterone therapy provides significant health benefits and reduces risk of cardiovascular disease. More important is that data from many observational and registry studies, demonstrated that longer durations of testosterone therapy were associated with greater health benefits and reduced cardiovascular risk. T therapy in men with T deficiency reduces the incidence of major adverse cardiovascular events attributed to improving overall metabolic function.

Relation between athletic club affiliation from school age and future serum free testosterone levels in Japan: A cross-sectional study

Background and Aims

Testosterone deficiency is often related to geriatric syndrome including erectile dysfunction, osteo-porosis, depression, cognitive impairment, cardiovascular diseases and frailty. Despite the existence of many studies on short-term exercise and serum testosterone levels, few research have focused on exercise habits from young age and testosterone values in middle-aged male. In this study, we investigated whether belonging to an athletic club from school age could predict serum-free testosterone (FT) levels.

Methods

The subjects were 1609 middle-aged male outpatients aged 40 years or older (median: 61 years, interquartile range: 54-69) who visited our hospital. Participants had their FT values measured in the morning hours during the period from December 2007 to June 2009. A questionnaire survey on exercise habits was conducted at the same time as the measurements. The exercise habit questionnaire was created based on whether the patients belonged to an athletic club in (a) elementary school, (b) junior high school, (c) high school, (d) college, (e) adult life, and (f) at the time of the test.

Results

There was only one positive response to the questionnaire among 456 patients (28% of total), followed by zero for 358 patients (22% of total). The number of patients with low-testosterone levels (FT < 8.5 pg/mL) according to the Japanese diagnostic criteria for late-onset of hypogonadism was 839 (52.1%). In multivariate analysis, it was shown that with low-testosterone levels (FT < 8.5 pg/mL), age (odds ratio [OR]: 1.065, 95% confidence interval [CI]: 1.052-1.079; p < 0.001), hypertension (OR: 3.489, 95% CI: 2.728-4.462; p < 0.001), type-2 diabetes (OR: 3.035, 95% CI: 2.296-4.01; p < 0.001), and dyslipidemia (OR: 2.039, 95% CI: 1.558-2.668; p < 0.001) were risk factors, and more than two positive responses to the questionnaire (OR: 0.886, 95% CI: 0.802-0.980; p = 0.018) were also a significant independent factor.

Conclusion

A sports club membership during school years may affect future testosterone levels.

Central androgen action reverses hypothalamic astrogliosis and atherogenic risk factors induced by orchiectomy and high-fat diet feeding in male mice

Hypogonadism in males confers elevated cardiovascular disease (CVD) risk by unknown mechanisms. Recent radiological evidence suggests that low testosterone (T) is associated with mediobasal hypothalamic (MBH) gliosis, a central nervous system (CNS) cellular response linked to metabolic dysfunction. To address mechanisms linking CNS androgen action to CVD risk, we generated a hypogonadal, hyperlipidemic mouse model with orchiectomy (ORX) combined with hepatic PCSK9 overexpression. After 4 wk of high-fat, high-sucrose diet (HFHS) consumption, despite equal body weights and glucose tolerance, androgen-deficient ORX mice had a more atherogenic lipid profile and increased liver and leukocyte inflammatory signaling compared with sham-operated control mice. Along with these early CVD risk indicators, ORX markedly amplified HFHS-induced astrogliosis in the MBH. Transcriptomic analysis further revealed that ORX and high-fat diet feeding induced upregulation of inflammatory pathways and downregulation of metabolic pathways in hypothalamic astrocytes. To interrogate the role of sex steroid signaling in the CNS in cardiometabolic risk and MBH inflammation, central infusion of T and dihydrotestosterone (DHT) was performed on ORX mice. Central DHT prevented MBH astrogliosis and reduced the liver inflammatory signaling and monocytosis induced by HFHS and ORX; T had a partial protective effect. Finally, a cross-sectional study in 41 adult men demonstrated a positive correlation between radiological evidence of MBH gliosis and plasma lipids. These findings demonstrate that T deficiency in combination with a Western-style diet promotes hypothalamic gliosis concomitant with increased atherogenic risk factors and provide supportive evidence for regulation of lipid metabolism and cardiometabolic risk determinants by the CNS action of sex steroids.NEW & NOTEWORTHY This study provides evidence that hypothalamic gliosis is a key early event through which androgen deficiency in combination with a Western-style diet might lead to cardiometabolic dysregulation in males. Furthermore, this work provides the first evidence in humans of a positive association between hypothalamic gliosis and LDL-cholesterol, advancing our knowledge of CNS influences on CVD risk progression.

Oxidative Stress and Inflammation Are Associated With Age-Related Endothelial Dysfunction in Men With Low Testosterone

CONTEXT

Vascular aging, including endothelial dysfunction secondary to oxidative stress and inflammation, increases the risk for age-associated cardiovascular disease (CVD). Low testosterone in middle-aged/older men is associated with increased CVD risk.

OBJECTIVE

We hypothesized that low testosterone contributes to age-associated endothelial dysfunction, related in part to greater oxidative stress and inflammation.

METHODS

This cross-sectional study included 58 healthy, nonsmoking men categorized as young (N = 20; age 29 ± 4 years; testosterone 500 ± 58 ng/dL), middle-aged/older with higher testosterone (N = 20; age 60 ± 6 years; testosterone 512 ± 115 ng/dL), and middle-aged/older lower testosterone (N = 18; age 59 ± 8 years; testosterone 269 ± 48 ng/dL). Brachial artery flow-mediated dilation (FMDBA) was measured during acute infusion of saline (control) and vitamin C (antioxidant). Markers of oxidative stress (total antioxidant status and oxidized low-density lipoprotein cholesterol), inflammation (interleukin [IL]-6 and C-reactive protein [CRP]), and androgen deficiency symptoms were also examined.

RESULTS

During saline, FMDBA was reduced in middle-aged/older compared with young, regardless of testosterone status (P < 0.001). FMDBA was reduced in middle-aged/older lower testosterone (3.7% ± 2.0%) compared with middle-aged/older higher testosterone (5.7% ± 2.2%; P = 0.021), independent of symptoms. Vitamin C increased FMDBA (to 5.3% ± 1.6%; P = 0.022) in middle-aged/older lower testosterone but had no effect in young (P = 0.992) or middle-aged/older higher testosterone (P = 0.250). FMDBA correlated with serum testosterone (r = 0.45; P < 0.001), IL-6 (r = -0.41; P = 0.002), and CRP (r = -0.28; P = 0.041).

CONCLUSION

Healthy middle-aged/older men with low testosterone appear to have greater age-associated endothelial dysfunction, related in part to greater oxidative stress and inflammation. These data suggest that low testosterone concentrations may contribute to accelerated vascular aging in men.

Low free testosterone level as a predictor of cardiovascular events in Japanese men with coronary risk factors

Aim: We investigated whether low plasma free testosterone (FT) levels could predict cardiovascular events (CVE) in Japanese men with coronary risk factors.Methods: Male patients with classical coronary risk factors who had undergone serum FT testing were enrolled. New incidences of CVE were retrospectively investigated among all eligible participants based on their medical records.Results: Overall, 466 male outpatients with coronary risk factors without a previous history of CVE were identified. Throughout the follow-up period (median = 92 months), 126 CVE occurred. The Kaplan-Meier survival analysis according to the tertiles of plasma FT levels revealed that patients with the lowest FT tertile (<6.5 pg/mL) had a higher likelihood of developing CVE than those with the highest tertile (>9.3 pg/mL) (p<.01). Multivariate analysis showed that increased frequency of CVE was observed with lower FT tertiles, independent of other coronary risk factors, with hazard ratios of 0.617 (95% CI, 0.389-0.976; p=.030) and 0.524 (95% CI, 0.309-0.887; p=.016) for the second and highest tertile relative to the lowest FT tertile, respectively.Conclusion: Among Japanese men with coronary risk factors, a lower FT level was a predictor for the development of cardiovascular diseases independent of other coronary risk factors and age.

Association Between Androgenic Alopecia and Coronary Artery Disease: A Cross-Sectional Study of Han Chinese Male Population

Purpose

This research aimed to investigate the correlation between androgenic alopecia (AGA) and coronary artery disease (CAD) and analyze its value in predicting the severity of coronary atherosclerosis in the Han Chinese male population.

Patients and Methods

A total of 402 Han Chinese male patients aged 28-75 years were enrolled and performed coronary angiography (CAG) after admission. According to the BASP classification, the participants were divided into mild, moderate and severe AGA. CAD was determined via CAG and defined as stenosis of ≥50% in at least one major coronary artery, and the Gensini score was calculated to evaluate the severity of coronary atherosclerosis.

Results

In this study, CAD status (P = 0.002), dyslipidemia status (P = 0.002), age (P = 0.003) and coronary atherosclerosis severity (P < 0.001) were different in patients with different levels of AGA. Multivariate logistic regression analysis revealed that severe AGA was independently correlated to CAD risk (OR, 2.111; 95% CI 1.152 to 3.870, P = 0.016), while the relative CAD risk of early-onset AGA was 2.292 (OR, 2.292; 95% CI 1.132 to 4.640, P = 0.021). AGA status (OR, 2.247; 95% CI 1.396 to 3.617, P = 0.001), severe AGA (OR, 2.360; 95% CI 1.506 to 3.699, P < 0.001) and early-onset AGA (OR, 3.474; 95% CI 2.069 to 5.832, P < 0.001) were all independently associated with the severity of coronary atherosclerosis. The area under the receiver operating characteristic (ROC) curve plotted using severe AGA was 0.601, which is predictive of severe coronary atherosclerosis. Moreover, the presence of severe AGA increases the risk of developing CAD associated with obesity (SI = 1.663, SIM = 1.222, AP = 0.289), diabetes (SI = 2.239, SIM = 1.149, AP = 0.503) and dyslipidemia (SI = 1.062, SIM = 0.646, AP = 0.045).

Conclusion

This study suggested that AGA is independently associated with CAD in a Han Chinese male population. AGA may be a simple and feasible method for screening CAD and indicative of the severity of coronary atherosclerosis.

The impact of rosuvastatin on hypothalamic-pituitary-testicular axis activity in metformin-treated and metformin-naïve men with low testosterone levels: a pilot study

Background

Intense statin therapy was found to impair testosterone production in men. Metformin administered to subjects with hypergonadotropic hypogonadism decreased gonadotropin production. The current study was aimed at investigating whether metformin treatment modulates the impact of high-dose rosuvastatin therapy on hypothalamic–pituitary–testicular axis activity in men.

Methods

The study included 43 very high cardiovascular risk men with late-onset hypogonadism, 20 of whom had been treated with metformin (1.7–3 g daily) for at least 6 months. In all subjects, unsuccessful initial statin treatment was replaced with rosuvastatin (20–40 mg daily). Plasma lipid levels, glucose homeostasis markers, as well as circulating levels of gonadotropins, testosterone, bioavailable testosterone, dehydroepiandrosterone-sulfate, prolactin, estradiol and creatinine were measured at the beginning of the study and 4 months later in 28 individuals in whom rosuvastatin reduced LDL cholesterol levels to below 70 mg/dL.

Results

There were no differences between treatment-induced changes in plasma lipids. In both study groups, rosuvastatin reduced total and bioavailable testosterone levels. However, only in metformin-naïve men, rosuvastatin increased LH and FSH levels and slightly impaired insulin sensitivity. The impact on gonadotropin concentrations correlated with treatment-induced decrease in testosterone levels. There were no significant differences between baseline and posttreatment values of dehydroepiandrosterone-sulfate, prolactin, estradiol and the glomerular filtration rate.

Conclusion

The obtained results suggest that metformin prevents the compensatory increase in gonadotrope function induced by intense statin therapy.

Association between vascular endothelial dysfunction and the inflammatory marker neopterin in patients with classic congenital adrenal hyperplasia

BACKGROUND AND AIMS

Patients with congenital adrenal hyperplasia (CAH) are at increased risk of cardiometabolic abnormalities. We aimed to evaluate vascular endothelial dysfunction and its association with serum neopterin (NP) levels in CAH patients.

METHODS

The study included 40 patients, with a mean age of 14.8 ± 2.6 years; 28 (70%) subjects were females. They were compared with 40 healthy controls matched in anthropometric evaluation and measurement of fasting lipids, glucose, insulin, homeostasis model assessment for insulin resistance [HOMA-IR], and serum NP levels (nmol/L). Vascular ultrasound was used to measure brachial artery flow-mediated dilation (FMD%) and carotid intima-media thickness (CA-IMT). According to the degree of control on medical treatment, patients were classified into poor (n = 12) and good (n = 28) control groups.

RESULTS

Compared to controls, CAH patients had lower brachial FMD% (4.60 ± 2.13 versus 9.31 ± 2.29, p = 0.001), similar CA-IMT (0.44 ± 0.08 versus 0.44 ± 0.06, p = nonsignificant) and higher NP (42.6 ± 11.6 versus 9.2 ± 3.8, p = 0.001). However, differences between poor and good control CAH patients were significant regarding FMD%, CA-IMT, and NP measurements. FMD% correlated significantly with NP (r = -0.54, p = 0.001), high-sensitivity CRP (r = -0.53, p = 0.001), HOMA-IR (r = -0.31, p = 0.01), CA-IMT (r = -0.22, p < 0.05), diastolic blood pressure (r = 0.32, p = 0.01) and systolic blood pressure (r = -0.022, p < 0.05). NP was the most significant independent predictor of FMD%, as determined by linear regression analysis (p = 0.001).

CONCLUSIONS

Our study showed that CAH patients had endothelial dysfunction, which is an early process of vascular affection. This was significantly associated with NP levels, suggesting a crucial role of inflammation in the pathogenesis of vascular damage. Further studies are needed to confirm our findings and to investigate the exact role of NP, as either protective or proatherothrombotic.

Regulatory Role of Sex Hormones in Cardiovascular Calcification

Sex differences in cardiovascular disease (CVD), including aortic stenosis, atherosclerosis and cardiovascular calcification, are well documented. High levels of testosterone, the primary male sex hormone, are associated with increased risk of cardiovascular calcification, whilst estrogen, the primary female sex hormone, is considered cardioprotective. Current understanding of sexual dimorphism in cardiovascular calcification is still very limited. This review assesses the evidence that the actions of sex hormones influence the development of cardiovascular calcification. We address the current question of whether sex hormones could play a role in the sexual dimorphism seen in cardiovascular calcification, by discussing potential mechanisms of actions of sex hormones and evidence in pre-clinical research. More advanced investigations and understanding of sex hormones in calcification could provide a better translational outcome for those suffering with cardiovascular calcification.

Functional state of the hypothalamus-pituitary-gonad axis in healthy men with various adaptation potential

The characterization of the functioning of the blood circulatory system of the organism in terms of its ability to adapt to environmental conditions includes the definition of adaptive potential (AP). The purpose of the study is to supplement the idea of adaptive potential in the aspect of its association with indicators of the hypothalamus-pituitary-gonadal system in healthy men living in the climatic conditions of the Arctic zone of the Russian Federation. The study involved 94 apparently healthy men. Serum hormone levels of the hypothalamus-pituitary-gonadal system were determined by enzyme-linked immunosorbent assay. Percent of men with satisfactory adaptation was 67%. Markers of increased tension in adaptive mechanisms include a decrease in values of testosterone, sex hormone -binding globulin, and testosterone / estradiol ratio. It has been shown that in individuals with a 4-th degree of adaptive potential, the activity of the pituitary-gonadal and the pituitary-adrenal cortex systems participating in the maintenance of the circulatory system is suppressed. That may be associated with a decrease in the reserves of hormone synthesis in these systems. An increase in the tension of the adaptive mechanisms of the circulatory system occurs with a decrease in the levels of anabolic hormones and a simultaneous increase in the level of estradiol as a compensatory reaction to maintain the function of the cardiovascular system. It is established that when moving northward beyond the border of the Arctic Circle an increase in the tension of the adaptive mechanisms of the circulatory system is noted for men living in extreme climatic conditions. The results of the study show a negative correlation of adaptive potential with the values of testosterone, sex hormone-binding globulin and the testosterone / estradiol ratio. The tension of the adaptive mechanisms of the blood circulatory system occurs with decreased sex hormones levels, which can be considered as a marker of disadaptation changes amid the risk of the ecological well-being of the population.

The impact of aerobic fitness on arterial stiffness and adrenal cortex hormones in middle-aged and older adults

An increase in arterial stiffness with advance aging is a risk for cardiovascular disease. Cardiovascular dysfunction is associated with the imbalance of adrenal cortex hormones, especially with the cortisol/dehydroepiandrosterone sulfate (DHEAs) ratio. However, the impact of aerobic fitness on arterial stiffness and cortisol/DHEAs ratio is unclear. The aim of this study was to investigate the relationship between aerobic fitness, arterial stiffness, and cortisol/DHEAs ratio. A total of 198 middle-aged and older adults (aged 50-79 years old) participated in this study. The aerobic fitness evaluated by peak oxygen consumption (VO_2peak), carotid-femoral pulse wave velocity (cfPWV) as an indicator of arterial stiffness, and serum cortisol and DHEAs and their ratio were measured. The subjects were divided into the lower (n = 100) and the higher (n = 98) aerobic fitness groups based on the median value of VO_2peak. There were no significant differences in serum cortisol and DHEAs concentration alone between the lower and higher fitness groups. However, the cortisol/DEHAs ratio and cfPWV in the higher fitness group was smaller than in the lower fitness group (p < 0.05). The cortisol/DHEAs ratio was significantly correlated with cfPWV (r = 0.159, p < 0.05). These findings suggest that the cortisol/DHEAs ratio is associated with aerobic fitness and arterial stiffness in middle-aged and older adults.

Recovery of serum testosterone following neoadjuvant androgen deprivation therapy in Japanese prostate cancer patients treated with low-dose rate brachytherapy

OBJECTIVE

To investigate the time course of total testosterone (TT) recovery after cessation of androgen deprivation therapy (ADT) in Japanese patients treated with brachytherapy.

METHODS

In total, 125 patients with prostate cancer received 6 months of neoadjuvant ADT (nADT) followed by low-dose rate (LDR) brachytherapy. TT was measured every 3 months after cessation of nADT, and some predictive factors affecting TT recovery were analyzed.

RESULTS

The cumulative incidence rates of TT recovery to normal levels (TT ≥ 3.0 ng/mL) after 12 and 24 months cessation were 49.6% and 81.6%, respectively. The median interval to recover to normal TT was 15 months. In multivariate analysis, the use of a gonadotropin-releasing hormone (GnRH) antagonist as nADT significantly earlier improved to recovery to normal TT level (p = 0.046). Conversely, higher body mass index (BMI) and hypertension significantly prolonged TT recovery to normal (p = 0.026 and p = 0.026, respectively).

CONCLUSIONS

Approximately one-fifth of patients still had low TT levels 2 years after the cessation of 6 months nADT before LDR brachytherapy. Use of a GnRH agonist, higher BMI, and hypertension were the predictive factors for slower TT recovery to normal TT levels after the cessation of nADT.

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.

Cysteine Sulfoxides Enhance Steroid Hormone Production via Activation of the Protein Kinase A Pathway in Testis-Derived I-10 Tumor Cells

Testosterone plays an important role in male sexual characteristics and maturation, and decreased testosterone levels increase the risk of several diseases. Recently, onion extract rich in cysteine sulfoxides, which are amino acids unique to onions, has been reported to alleviate age-related symptoms resulting from decreased testosterone levels in males. However, the mechanism underlying the suppression of low testosterone levels by cysteine sulfoxides has not been elucidated. In this study, we found that onion extract containing cysteine sulfoxides enhanced progesterone, a precursor of testosterone, in mouse testis-derived I-10 tumor cells. Furthermore, cysteine sulfoxides activated protein kinase A (PKA) and cyclic adenosine monophosphate response element-binding protein, which are key factors in steroidogenesis. These results suggest that cysteine sulfoxides enhance steroid hormone production via activation of the PKA signaling pathway.

Role of High Physical Fitness in Deterioration of Male Sexual Function in Japanese Adult Men

Male sexual function is regulated by vascular function and impaired vascular function is closely related with erectile dysfunction (ED). Vascular functions are positively influenced by physical fitness (i.e., aerobic capacity, muscle strength, and flexibility). The detailed associations between physical fitness and male sexual function remain poorly understood. The present study aimed to clarify the influence of physical fitness on male sexual function. In 177 adult men, peak oxygen consumption (VO_{2 peak}), handgrip strength (HGS), and sit and reach were measured as indices of physical fitness. Arterial stiffness and erectile function were assessed by carotid-femoral pulse wave velocity (cfPWV) and the International Index of Erectile Function 5 (IIEF5) questionnaire, respectively. IIEF5 score was significantly correlated with VO_{2 peak} ( r_s = 0.52), HGS ( r_s = 0.37), and cfPWV ( r_s = -0.44); and multivariate linear regression analyses showed that VO_{2 peak}, HGS, and cfPWV were significantly associated with IIEF5 score after considering confounders. The receiver operator characteristic curve analysis suggested that the cutoff values for predicting ED were 29.0 ml/min/kg for VO_{2 peak} and 39.3 kg for HGS. The IIEF5 score was the highest in the subjects with the values of both VO_{2 peak} and HGS were higher than their respective cutoff values, while the IIEF5 score was the lowest in the subjects with the values of both VO_{2 peak} and HGS were lower than their respective cutoff values. These results suggest that the maintenance of high aerobic capacity and muscular strength may offset deterioration of male sexual function.

Effectiveness of testosterone therapy in hypogonadal patients and its controversial adverse impact on the cardiovascular system

Testosterone is the major male hormone produced by testicles which are directly associated with man's appearance and secondary sexual developments. Androgen deficiency starts when the male hormonal level falls from its normal range though, in youngsters, the deficiency occurs due to disruption of the normal functioning of pituitary, hypothalamus glands, and testes. Thus, testosterone replacement therapy was already known for the treatment of androgen deficiency with lesser risks of producing cardiovascular problems. Since from previous years, the treatment threshold in the form of testosterone replacement therapy has effectively increased to that extent that it was prescribed for those conditions which it was considered as inappropriate. However, there are some research studies and clinical trials available that proposed the higher risk of inducing cardiovascular disease with the use of testosterone replacement therapy. Thus under the light of these results, the FDA has published the report of the increased risk of cardiovascular disease with the increased use of testosterone replacement therapy. Nevertheless, there is not a single trial available or designed that could evaluate the risk of cardiovascular events with the use of testosterone replacement therapy. As a result, the use of testosterone still questioned the cardiovascular safety of this replacement therapy. Thus, this literature outlines the distribution pattern of disease by investigating the data and link between serum testosterone level and the cardiovascular disease, also the prescription data of testosterone replacement therapy patients and their tendency of inducing cardiovascular disease, meta-analysis and the trials regarding testosterone replacement therapy and its connection with the risks of causing cardiovascular disease and lastly, the possible effects of testosterone replacement therapy on the cardiovascular system. This study aims to evaluate the available evidence regarding the use of testosterone replacement therapy when choosing it as a treatment plan for their patients.

Endogenous Testosterone Levels and the Risk of Incident Cardiovascular Events in Elderly Men: The MrOS Prospective Study

Context

Observational studies show discordant links between endogenous testosterone levels and cardiovascular diseases (CVD).

Objective

We assessed whether sex hormones and sex hormone–binding globulin (SHBG) are associated with CVD in community-dwelling elderly men.

Design, Setting and Participants

Prospective study of incident CVD among 552 men ≥ 65 years in the MrOS Sleep Study without prevalent CVD and no testosterone therapy at baseline.

Outcomes

Fasting serum levels of total testosterone and estradiol were measured using liquid chromatography-mass spectrometry, and SHBG by chemiluminescent substrate. The association of sex hormones and SHBG with incident coronary heart disease (CHD), cerebrovascular (stroke and transient ischemic attack) and peripheral arterial disease (PAD) events were assessed by quartile and per SD increase in proportional hazards models.

Results

After 7.4 years, 137 men (24.8%) had at least 1 CVD event: 90 CHD, 45 cerebrovascular and 26 PAD. The risk of incident CVD events was not associated with quartiles of baseline sex hormones or SHBG (all P ≥ 0.16). For +1 SD in total testosterone, the multivariate-adjusted hazard ratio was 1.04 (95% CI, 0.80-1.34) for CHD, 0.86 (0.60-1.25) for cerebrovascular, and 0.81 (0.52-1.26) for PAD events. When analyzed as continuous variables or comparing highest to low quartile, levels of bioavailable testosterone, total estradiol, testosterone/estradiol ratio and SHBG were not associated with CVD events.

Conclusions

In community-dwelling elderly men, endogenous levels of testosterone, estradiol, and SHBG were not associated with increased risk of CHD, cerebrovascular, or PAD events. These results are limited by the small number of events and should be explored in future studies.

Deterioration of sexual function is associated with central hemodynamics in adult Japanese men

Elevated aortic blood pressure is more strongly related to the onset of cardiovascular disease (CVD) than elevated brachial blood pressure. On the other hand, erectile dysfunction (ED) is a peripheral vascular disfunction and is also associated with CVD; however, the association between aortic blood pressure and ED has not yet been clarified. Therefore, we aimed to investigate the association between ED severity and aortic blood pressure in adult men. In 253 Japanese adult men (59 ± 16 years), aortic (estimated using a generalized transfer function) and peripheral hemodynamics were measured. Erectile function was assessed with a questionnaire (the International Index of Erectile Function 5: IIEF5), and participants were stratified into three groups based on the IIEF5 score (no ED, mild-to-moderate ED, and moderate-to-severe ED). Aortic systolic blood pressure (SBP) and pulse pressure (PP) were significantly higher in subjects with moderate-to-severe ED than in subjects with no ED or mild-to-moderate ED. In addition, the severity of ED was significantly associated with the time to reflection, augmentation pressure, and augmentation index. Multivariate linear regression analyses suggested that moderate-to-severe ED was significantly associated with aortic SBP and PP (β = 0.129; p = 0.047, β = 0.165; p = 0.013, respectively) but not brachial SBP or PP, after confounding factors were considered. These results suggest that moderate-to-severe ED is associated with elevated aortic blood pressure due to an earlier arrival of the reflected wave and is an independent predictor of elevated aortic blood pressure in Japanese men.

Clinical and Genetic Risk Factors for Adverse Metabolic Outcomes in North American Testicular Cancer Survivors

Background: Testicular cancer survivors (TCS) are at significantly increased risk for cardiovascular disease (CVD), with metabolic syndrome (MetS) an established risk factor. No study has addressed clinical and genetic MetS risk factors in North American TCS. Patients and Methods: TCS were aged <55 years at diagnosis and received first-line chemotherapy. Patients underwent physical examination, and had lipid panels, testosterone, and soluble cell adhesion molecule-1 (sICAM-1) evaluated. A single nucleotide polymorphism in rs523349 (5-α-reductase gene, SRD5A2), recently implicated in MetS risk, was genotyped. Using standard criteria, MetS was defined as ≥3 of the following: hypertension, abdominal obesity, hypertriglyceridemia, decreased high-density lipoprotein (HDL) cholesterol level, and diabetes. Matched controls were derived from the National Health and Nutrition Examination Survey. Results: We evaluated 486 TCS (median age, 38.1 years). TCS had a higher prevalence of hypertension versus controls (43.2% vs 30.7%; P<.001) but were less likely to have decreased HDL levels (23.7% vs 34.8%; P<.001) or abdominal obesity (28.2% vs 40.1%; P<.001). Overall MetS frequency was similar in TCS and controls (21.0% vs 22.4%; P=.59), did not differ by treatment (P=.20), and was not related to rs523349 (P=.61). For other CVD risk factors, TCS were significantly more likely to have elevated low-density lipoprotein (LDL) cholesterol levels (17.7% vs 9.3%; P<.001), total cholesterol levels (26.3% vs 11.1%; P<.001), and body mass index ≥25 kg/m² (75.1% vs 69.1%; P=.04). On multivariate analysis, age at evaluation (P<.001), testosterone level ≤3.0 ng/mL (odds ratio [OR], 2.06; P=.005), and elevated sICAM-1 level (OR_{highest vs lowest quartile}, 3.58; P=.001) were significantly associated with MetS. Conclusions and Recommendations: Metabolic abnormalities in TCS are characterized by hypertension and increased LDL and total cholesterol levels but lower rates of decreased HDL levels and abdominal obesity, signifying possible shifts in fat distribution and fat metabolism. These changes are accompanied by hypogonadism and inflammation. TCS have a high prevalence of CVD risk factors that may not be entirely captured by standard MetS criteria. Cancer treatment-associated MetS requires further characterization.

Testosterone and the Heart

The development of a subnormal level of testosterone (T) is not universal in ageing men, with 75% of men retaining normal levels. However, a substantial number of men do develop T deficiency (TD), with many of them carrying a portfolio of cardiovascular (CV) risk factors, including type 2 diabetes (T2D) and the metabolic syndrome. TD increases the risk of CV disease (CVD) and the risk of developing T2D and the metabolic syndrome. The key symptoms suggesting low T are sexual in nature, including erectile dysfunction (ED), loss of night-time erections and reduced libido. Many men with heart disease, if asked, admit to ED being present; a problem that is often compounded by drugs used to treat CVD. A large number of studies and meta-analyses have provided evidence of the link between TD and an increase in CVD and total mortality. Patients with chronic heart failure (CHF) who have TD have a poor prognosis and this is associated with more frequent admissions and increased mortality compared with those who do not have TD. Conversely, in men with symptoms and documented TD, T therapy has been shown to have beneficial effects, namely improvement in exercise capacity in patients with CHF, improvement of myocardial ischaemia and coronary artery disease. Reductions in BMI and waist circumference, and improvements in glycaemic control and lipid profiles, are observed in T-deficient men receiving T therapy. These effects might be expected to translate into benefits and there are more than 100 studies showing CV benefit or improved CV risk factors with T therapy. There are flawed retrospective and prescribing data studies that have suggested increased mortality in treated men, which has led to regulatory warnings, and one placebo-controlled study demonstrating an increase in coronary artery non-calcified and total plaque volumes in men treated with T, which is open for debate. Men with ED and TD who fail to respond to phosphodiesterase type 5 (PDE5) inhibitors can be salvaged by treating the TD. There are data to suggest that T and PDE5 inhibitors may act synergistically to reduce CV risk.

Prognostic value of total testosterone levels in patients with acute coronary syndromes

BACKGROUND

Endogenous testosterone levels decrease in men with aging. Controversies persist regarding the screening and treatment of low testosterone levels in patients with acute coronary syndromes (ACS).

METHODS AND RESULTS

Total serum testosterone levels were measured in 1054 men hospitalized for ACS that were part of a Swiss prospective cohort. Total testosterone levels were classified first in tertiles and using the cut-off of 300 ng/dL. Primary endpoint was all-cause mortality at one year. Cox regression models adjusting for the GRACE score (composite of age, heart rate systolic blood pressure, creatinine, cardiac arrest at admission, ST segment deviation, abnormal troponin enzyme and Killip classification), preexisting diabetes and inflammation (high-sensitivity C-reactive protein). A total of 430 men (40.8%) had total testosterone levels ≤300 ng/dL. Low total testosterone levels were correlated with lower high-density lipoprotein cholesterol and higher triglycerides, high-sensitivity C-reactive protein, high-sensitivity troponin T, N-terminal-pro B-type natriuretic peptide and glucose levels (all p < 0.01). Patients in the lowest testosterone tertile had a mortality rate at one-year of 5.4% compared with 2.9% in the highest tertile with an unadjusted hazard ratio of 1.92 (95% confidence interval 0.96-1.90, p = 0.095) and adjusted hazard ratio of 1.26 (95% confidence interval 0.57-2.78, p = 0.565). In an exploratory analysis, the highest mortality rate (10.3%) was observed in men aged >65 years old belonging to the lowest testosterone tertile.

CONCLUSION

In this large population of men with ACS, we found a prevalence of low total endogenous testosterone levels of almost 40%. However, low testosterone levels were not significantly associated with mortality after adjustment for high-risk confounders.

Clinical Significance of Low Blood Testosterone Concentration in Men as a Cardiovascular Risk Factor From the Perspective of Blood Rheology

Background

Recent clinical studies have indicated the importance of low blood testosterone concentration or whole blood passage time (WBPT) which reflects blood rheology as a cardiovascular risk factor. On the contrary, there are no reports regarding the association of blood testosterone concentrations and WBPT. This cross-sectional study aimed to elucidate the clinical significance of low blood testosterone concentration in men as a cardiovascular risk factor from the perspective of blood rheology using WBPT.

Methods

In total, 382 male patients with traditional cardiovascular risk factor and no history of cardiovascular disease (age (mean ± standard deviation (SD)), 64 ± 10 years) were enrolled. Serum total testosterone concentration (T-T) was measured as a marker of testosterone level in vivo, and WBPT was also measured using microchannel array flow analyzer as a commercial device. The relationship between T-T and WBPT was evaluated.

Results

There was a significantly negative correlation between T-T and WBPT (r = -0.45; P < 0.001). Furthermore, multiple regression analysis revealed that T-T (β = -0.25; P < 0.001) could be selected as an independent variable when WBPT was used as a subordinate factor. According to receiver operating characteristic curve analysis and the result of the previous report that determined WBPT of > 72.4 s as a risk for incidence of primary cardiovascular disease, T-T of < 551.4 ng/dL is the optimal cut-off point for discriminating high WBPT.

Conclusions

The study results showed that T-T is independently and inversely associated with WBPT in male patients with traditional cardiovascular risk factor and no history of cardiovascular disease. In addition, this study suggests that the incidence of primary cardiovascular events can be prevented by maintaining T-T at approximately ≥ 550 ng/dL from the perspective of blood rheology.

A long-term perspective on cardiovascular job stress research

This review provides perspectives on cardiovascular occupational stress research since the 1960s until now. The author argues for closer links between basic science and clinical follow‐up examinations of patients. In an excellent way urinary excretion of adrenaline and noradrenaline during wake hours mirrors day to day or week to week variations in sympathomedullary activity which could be related to variations in the patient's and cardiovascular and psychosocial situation. Modern methods for following variations over time in heart contractility should also be related to the patients' psychosocial situation. In addition the author argues for more extensive use of the increasing knowledge regarding regeneration and vagal activity in relation to variations in job conditions and development or prevention of cardiovascular disease.

Clinical Impact of Blood Testosterone Concentration on Cardio-Ankle Vascular Index in Female Patients With Type 2 Diabetes Mellitus

Background

Information regarding testosterone as a significant risk factor of cardiovascular disease (CVD) in female patients with type 2 diabetes mellitus (DM) is limited. However, some clinical studies reported the importance of cardio-ankle vascular index (CAVI) as a novel physiological marker of arterial function in type 2 DM. This cross-sectional study aimed to elucidate the clinical effects of blood testosterone concentration on CAVI in female patients with type 2 DM.

Methods

A total of 238 postmenopausal patients including 97 with a history of CVD with type 2 DM (age (mean ± standard deviation (SD)), 73 ± 9 years) were enrolled. CAVI was measured according to the standard technique, and serum total testosterone concentration (T-T) was also measured as a testosterone level marker in vivo. The relationship between CAVI and T-T was evaluated.

Results

CAVI is significantly higher (CVD vs. non-CVD: 10.2 ± 1.2 vs. 9.2 ± 1.0, P < 0.001), and log-T-T significantly lower (CVD vs. non-CVD: 1.2 ± 0.2 ng/dL vs. 1.5 ± 0.2 ng/dL, P < 0.001) in patients with CVD than those without CVD. CAVI was significantly negatively correlated with log-T-T (r = -0.41; P < 0.001). Furthermore, multiple regression analysis indicated that CVD (β = 0.23; P < 0.001) and log-T-T (β = -0.18; P < 0.01) were selected as independent subordinate variables for CAVI.

Conclusions

This study showed that T-T was independently inversely associated with CAVI, indicating that low testosterone concentration is a considerable risk factor for the progression of arterial dysfunction in female patients with type 2 DM.

Is a Previously or Currently Reduced Testosterone Level in Male Patients with Type 2 Diabetes Mellitus a Risk Factor for the Development of Coronary Artery Disease? A Systematic Review and Meta-analysis

INTRODUCTION

We aimed to systematically investigate the association between testosterone level and cardiovascular risk in male patients with type 2 diabetes mellitus (T2DM) by comparing male T2DM patients with low testosterone levels to male T2DM patients with normal testosterone levels at baseline in terms of the number of cases of coronary artery disease (CAD).

METHODS

Online databases were carefully searched for studies relating to testosterone, diabetes mellitus, and cardiovascular risk by using the search terms 'testosterone,' 'diabetes mellitus,' and 'coronary artery/cardiovascular disease.' The only endpoint in this analysis was CAD/atherosclerosis/coronary plaque/major adverse coronary event prior to or following testosterone reduction at baseline. The analytical parameters used in this analysis were the risk ratio (RR) with the 95% confidence interval (CI), as obtained using the RevMan 5.3 software.

RESULTS

3467 male patients with T2DM (1079 patients with a low testosterone level versus 2388 patients with a normal testosterone level) were included. The results of this analysis showed that when a random effects model was used, a higher risk of CAD/cardiovascular disease was observed in diabetic patients with a low testosterone level than in those with a normal testosterone level (RR 1.24, 95% CI 0.94-1.63; P = 0.13). However, the difference in risk was not statistically significant. Similarly, with a fixed effects model, a low testosterone level was associated with a higher CAD/cardiovascular risk of disease (RR 1.12, 95% CI 0.98-1.34; P = 0.08); in this case, the difference in risk between the T2DM patients with low and normal testosterone levels approached statistical significance.

CONCLUSION

A previously or currently reduced testosterone level was not found to be statistically significantly associated with a high risk of CAD/cardiovascular disease in male patients with T2DM. However, the difference in risk between the T2DM patients with low and normal testosterone levels was observed to approach statistical significance.

Sexual Function Is an Indicator of Central Arterial Stiffness and Arterial Stiffness Gradient in Japanese Adult Men

Background

As arterial stiffness increases in the absence of subjective symptoms, a personal indicator that reflects increased risk of cardiovascular disease is necessary. Penile erection is regulated by vascular function, and atherosclerosis affects the penile artery earlier than it affects the coronary and carotid arteries. Therefore, we hypothesized that deterioration of erectile function could be a marker of increased risk for cardiovascular disease. To test our hypothesis, we assessed erectile function and arterial stiffness in a cross‐sectional study.

Methods and Results

Carotid‐femoral pulse wave velocity (PWV), brachial‐ankle PWV, femoral‐ankle PWV, and arterial stiffness gradient (PWV ratio: carotid‐femoral PWV/femoral‐ankle PWV) were measured as indexes of central, systemic, and peripheral arterial stiffness and peripheral organ damage, respectively, in 317 adult men. In addition, erectile function was assessed by using the questionnaire International Index of Erectile Function 5 (a descending score indicates worsening of erectile function). The scores of male sexual function were inversely correlated with carotid‐femoral PWV (r_s=−0.41), brachial‐ankle PWV (r_s=−0.35), femoral‐ankle PWV (r_s=−0.19), and PWV ratio (r_s=−0.33). Furthermore, multivariate linear regression analyses revealed that International Index of Erectile Function 5 scores were significantly associated with carotid‐femoral PWV (β=−0.22) and PWV ratio (β=−0.25), but not with brachial‐ankle PWV and femoral‐ankle PWV.

Conclusions

Our results indicated that erectile function is independently associated with central arterial stiffness and peripheral organ damage. These findings suggest that male sexual function could be an easily identifiable and independent marker of increased central arterial stiffness and peripheral organ damage.

Cardiovascular benefits and risks of testosterone replacement therapy in older men with low testosterone

Many studies have shown that low testosterone (T) levels have been associated with increased risk for cardiovascular (CV) events, type 2 diabetes mellitus (T2DM), and strokes. In contrast, many other studies have demonstrated that normal T levels or the normalization of low T levels with testosterone replacement therapy (TRT) is associated with decreased incidence of CV events, T2DM, and strokes, besides improving sexual function and the quality of life. However, recent studies have indicated that TRT could lead to increased incidence of CV events and strokes. These latter studies have created a great controversy among physicians regarding these findings, who question the validity of their results. In order to get a better perspective on the current status of TRT in hypogonadal men, a focused Medline and EMBASE search of the English language literature was conducted between 2010 and 2017 using the terms hypogonadism, low Testosterone, cardiovascular disease, testosterone replacement therapy, benefits, risks, older men, mechanism of action, and 58 papers with pertinent information were selected and 48 papers were rejected. The selected papers will be discussed in this review. In conclusion, based on the current status of TRT, the majority of studies indicate that TRT is safe and is associated with prevention of CVD and strokes in hypogonadal men. However, the evidence is not uniform and the therefore, decision to administer TRT should be discussed with the patient till more definitive information becomes available.

The relationship between lipoprotein-associated phospholipase A2 with cardiovascular risk factors in testosterone deficiency

Objective

Lipoprotein-associated phospholipase A2 (Lp-PLA2) which is believed to play a role in atherosclerotic inflammatory process due to its function in hydrolysis of phospholipids and release of pro-inflammatory products, is considered as a novel biomarker for vascular risk. In this study we aimed to investigate the alterations in Lp-PLA2 and its relationship with other cardiovascular risk factors in patients with testosterone deficiency.

Material and methods

Forty hypogonadic male and 30 healthy male aged between 18-50 years were enrolled in this study. Height-weight, waist-to-hip circumference, body mass index (BMI) blood pressure, and body fat measurements were performed in all subjects. Blood glucose, albumin, total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, high sensitive C-reactive protein (hs-CRP), apo-A1, apo-B, fibrinogen, insulin, total testosterone, sex hormone binding globulin (SHBG), small dense low-density lipoprotein (sd-LDL), paraoxonase 1, oxidized low-density lipoprotein (ox-LDL) and Lp-PLA 2 values were measured. Free and bioavailable testosterone levels were calculated. Data management was carried out with the statistical program SAS Version 9.2. Statistical evaluations were performed using Analysis of Variance (ANOVA), Kruskal-Wallis test, Wilcoxon test, correlation analysis and chi-square analysis. P values <0.05 were considered statistically significant.

Results

In patients with hypogonadism, significant increase in Lp-PLA2 levels were accompanied with risk factors of atherosclerosis, such as increase in total cholesterol, apo-B, sd-LDL, weight, BMI, body fat percentage, and decrease in paraoxonase 1 levels. Although the differences were not significant, similarly ox-LDL, hs-CRP, triglyceride, LDL-cholesterol levels were found to be higher in patients with hypogonadism compared to the control group. The mean level of Lp-PLA2 was the highest when compared with the group of secondary hypogonadism with the lowest testosterone level.

Conlusion

Our study has demonstrated that the testosterone deficiency increases cardiovascular risk via its effects on lipid metabolism and Lp-PLA2 can be used to assess this risk.

A novel function of geranylgeraniol in regulating testosterone production

Isoprenoids play widely differing roles in various physiological processes in animals and plants. Geranylgeraniol (GGOH) is an isoprenoid found in plants, and is an important metabolic derivative in the isoprenoid/cholesterol synthesis pathway. Earlier studies focused on GGOH's ability to improve the side effects of bisphosphonate therapy by regulating the mevalonate pathway. More recently, the mevalonate pathway-independent effects of GGOH have been described, including anti-inflammatory, anti-tumorigenic, and neuroprotective activities. It is noteworthy that GGOH regulates the steroidogenesis pathway in testis-derived I-10 tumor cells. Testosterone is a hormone produced via steroidogenesis in testicles and plays a role in fetal development and the male reproductive system. GGOH enhanced testosterone and progesterone (its precursor) levels in I-10 cells by activating adenylate cyclase via cAMP/PKA signaling, without altering phosphodiesterase activity. These findings highlight the potential benefits of GGOH as a therapeutic agent for low testosterone levels, such as late-onset hypogonadism in men.

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.

Benefits and Health Implications of Testosterone Therapy in Men With Testosterone Deficiency

INTRODUCTION

Testosterone (T) deficiency (TD; hypogonadism) has deleterious effects on men's health; negatively affects glycometabolic and cardiometabolic functions, body composition, and bone mineral density; contributes to anemia and sexual dysfunction; and lowers quality of life. T therapy (TTh) has been used for the past 8 decades to treat TD, with positive effects on signs and symptoms of TD.

AIM

To summarize the health benefits of TTh in men with TD.

METHODS

A comprehensive literature search was carried out using PubMed, articles relevant to TTh were accessed and evaluated, and a comprehensive summary was synthesized.

MAIN OUTCOME MEASURES

Improvements in signs and symptoms of TD reported in observational studies, registries, clinical trials, and meta-analyses were reviewed and summarized.

RESULTS

A large body of evidence provides significant valuable information pertaining to the therapeutic value of TTh in men with TD. TTh in men with TD provides real health benefits for bone mineral density, anemia, sexual function, glycometabolic and cardiometabolic function, and improvements in body composition, anthropometric parameters, and quality of life.

CONCLUSION

TTh in the physiologic range for men with TD is a safe and effective therapeutic modality and imparts great benefits on men's health and quality of life. Traish AM. Benefits and Health Implications of Testosterone Therapy in Men With Testosterone Deficiency. Sex Med Rev 2018;6:86-105.

The biological and clinical advances of androgen receptor function in age-related diseases and cancer [Review]

Hormonal alterations with aging contribute to the pathogenesis of several diseases. Androgens mediate their effects predominantly through binding to the androgen receptor (AR), a member of the ligand-dependent nuclear receptor superfamily. By androgen treatment, AR is recruited to specific genomic loci dependent on tissue specific pioneer factors to regulate target gene expression. Recent studies have revealed the epigenetic modulation by AR-associated histone modifiers and the roles of non-coding RNAs in AR signaling. Androgens are male sex hormone to induce differentiation of the male reproductive system required for the establishment of adult sexual function. As shown by several reports using AR knockout mouse models, androgens also have anabolic functions in several tissues such as bone, muscle and central nervous systems. Notably, AR has a central role in prostate cancer progression. Prostate cancer is the most frequently diagnosed cancer in men. Androgen-deprivation therapy for cancer patients and decline of serum androgen with aging promote several diseases associated with aging and quality of life of older men such as osteoporosis, sarcopenia and dementia. Thus, androgen replacement therapy for treating late onset hypogonadism (LOH) or new epigenetic regulators have the potential to overcome the symptoms caused by the low androgen, although adverse effects for cardiovascular diseases have been reported. Given the increasing longevity and consequent rise of age-related diseases and prostate cancer patients, a more understanding of the AR actions in male health remains a high research priority.

Association of Testosterone Replacement Therapy and the Incidence of a Composite of Postoperative In-hospital Mortality and Cardiovascular Events in Men Undergoing Noncardiac Surgery

Background

Whether patients on testosterone replacement therapy undergoing noncardiac surgery have an increased risk of postoperative in-hospital mortality and cardiovascular events remains unknown. We therefore sought to identify the impact of testosterone replacement on the incidence of a composite of postoperative in-hospital mortality and cardiovascular events in men undergoing noncardiac surgery.

Methods

Data from male American Society of Anesthesiologists I through IV patients 40 yr or older who underwent noncardiac surgery between May 2005 and December 2015 at the Cleveland Clinic (Cleveland, Ohio) main campus were included. The primary exposure was preoperative testosterone use. The primary outcome was a composite of postoperative in-hospital mortality and cardiovascular events. We compared patients who received testosterone and those who did not using propensity score matching within surgical procedure matches.

Results

Among 49,273 patients who met inclusion and exclusion criteria, 947 patients on testosterone were matched to 4,598 nontestosterone patients. The incidence of in-hospital mortality was 1.3% in the testosterone group and 1.1% in the nontestosterone group, giving an odds ratio of 1.17 (99% CI, 0.51 to 2.68; P = 0.63). The incidence of myocardial infarction was 0.2% in the testosterone group and 0.6% in the nontestosterone group (odds ratio = 0.34; 99% CI, 0.05 to 2.28; P = 0.15). Similarly, no significant difference was found in stroke (testosterone vs. nontestosterone: 2.0% vs. 2.1%), pulmonary embolism (0.5% vs. 0.7%), or deep venous thrombosis (2.0% vs. 1.7%).

Conclusions

Preoperative testosterone is not associated with an increased incidence of a composite of postoperative in-hospital mortality and cardiovascular events.

Therapeutic Targeting of Cellular Stress to Prevent Cardiovascular Disease: A Review of the Evidence

The availability of effective drugs targeting the major risk factors of cardiovascular disease (CVD) has reduced morbidity and mortality. Cumulative relative risk of CVD events can be reduced by 75 % with a combination of aspirin, a β-adrenoceptor antagonist (β-blocker), an HMG-CoA reductase inhibitor (statin), and an angiotensin-converting enzyme inhibitor. The principal pharmacodynamics of these drugs cannot explain the entirety of their cardioprotective action, as other drugs with similar pharmacologic targets have not been associated with favorable clinical effects. This raises the possibility that the cardioprotective drugs have a unique pleiotropic activity that contributes to their clinical efficacy. Recent data suggest that reducing cellular stress such as oxidative, inflammatory, and endoplasmic reticulum stress, might be a common denominator of the drugs with proven efficacy in reducing CVD risk. In this communication, the evidence in favor of this hypothesis is discussed, and ongoing trials with therapeutic agents targeting cellular stresses are reviewed.

Lower urinary tract symptoms/benign prostatic hypertrophy and vascular function: Role of the nitric oxide-phosphodiesterase type 5-cyclic guanosine 3',5'-monophosphate pathway

It is well known that there is an association of lower urinary tract symptoms/benign prostatic hypertrophy with cardiovascular disease, suggesting that lower urinary tract symptoms/benign prostatic hypertrophy is a risk factor for cardiovascular events. Vascular function, including endothelial function and vascular smooth muscle function, is involved in the pathogenesis, maintenance and development of atherosclerosis, leading to cardiovascular events. Vascular dysfunction per se should also contribute to lower urinary tract symptoms/benign prostatic hypertrophy. Both lower urinary tract symptoms/benign prostatic hypertrophy and vascular dysfunction have cardiovascular risk factors, such as hypertension, dyslipidemia, diabetes mellitus, aging, obesity and smoking. Inactivation of the phosphodiesterase type 5-cyclic guanosine 3',5'-monophosphate-nitric oxide pathway causes lower urinary tract symptoms/benign prostatic hypertrophy through an enhancement of sympathetic nervous activity, endothelial dysfunction, increase in Rho-associated kinase activity and vasoconstriction, and decrease in blood flow of pelvic viscera. Both endogenous nitric oxide and exogenous nitric oxide act as vasodilators on vascular smooth muscle cells through an increase in the content of cyclic guanosine 3',5'-monophosphate, which is inactivated by phosphodiesterase type 5. In a clinical setting, phosphodiesterase type 5 inhibitors are widely used in patients with lower urinary tract symptoms/benign prostatic hypertrophy. Phosphodiesterase type 5 inhibitors might have beneficial effects on vascular function through not only inhibition of cyclic guanosine 3',5'-monophosphate degradation, but also increases in testosterone levels and nitric oxide bioavailability, increase in the number and improvement of the function of endothelial progenitor cells, and decrease in insulin resistance. In the present review, the relationships between lower urinary tract symptoms/benign prostatic hypertrophy, the phosphodiesterase type 5-nitric oxide-cyclic guanosine 3',5'-monophosphate pathway, vascular function and cardiovascular outcomes are examined.

Low testosterone and clinical outcomes in Chinese men with type 2 diabetes mellitus - Hong Kong Diabetes Registry

AIMS

To assess the implications of low testosterone on cardiovascular risk factors, metabolic syndrome (MES) and clinical outcomes in Chinese men with Type 2 Diabetes (T2D).

METHODS

A prospective cohort study carried out in a university hospital involving a consecutive cohort of 1239 Chinese men with T2D and a median disease duration of 9years followed up for 4.8years. Clinical characteristics, frequency of MES, serum total testosterone and clinical events were analyzed. Multivariate logistic regression was performed to examine the independent association of low testosterone with MES after adjustment for confounding covariates. Cox proportional hazards regression analysis was used to derive hazard ratio for clinical outcomes.

RESULTS

More men with low testosterone had cardiovascular-renal disease and MES than those with normal testosterone. The adjusted odds ratio (OR) of low testosterone for MES was 2.63 (95% Confidence Interval [CI] 1.56-4.61). After a median follow-up of 4.8years, the hazard ratio (HR) of low testosterone was 2.22 (95% CI 1.23-4.01) for incident non-prostate cancer. In a multivariate Cox-regression model, the HRs were attenuated but remained significant with adjustment for MES and renal parameters.

CONCLUSIONS

Chinese men with low testosterone had high prevalence of cardiovascular disease and MES with high incidence non-prostate cancer.

Testosterone as a marker of coronary artery disease severity in middle aged males

Historically, higher levels of serum testosterone were presumed deleterious to the cardiovascular system. In the last two decades, studies have suggested that low testosterone levels are associated with increased prevalence of risk factors for cardiovascular disease (CVD), including dyslipidemia and diabetes. This is a cross sectional study. The aim of our study was to determine the relationship between serum testosterone levels and angiographic severity of coronary artery disease (CAD). Serum testosterone levels were also correlated with flow mediated dilation of brachial artery (BAFMD) - an indicator of endothelial function. Consecutive male patients, aged 40-60 years, admitted for coronary angiography (CAG) with symptoms suggestive of CAD, were included in the study. Out of the 92 patients included in the study, 32 patients had normal coronaries and 60 had CAD on coronary angiography. Severity of CAD was determined by Gensini coronary score. The group with CAD had significantly lower levels of total serum testosterone (363±147.1 vs 532.09±150.5ng/dl, p<0.001), free testosterone (7.1215±3.012 vs 10.4419±2.75ng/dl, p<0.001) and bioavailable testosterone (166.17±64.810 vs 247.94±62.504ng/dl, p<0.001) when compared to controls. Adjusting for the traditional risk factors for CAD, a multiple linear regression analysis showed that low testosterone was an independent predictor of severity of CAD (β=-0.007, p<0.001). This study also showed that levels of total, free and bioavailable testosterone correlated positively with BAFMD %.

Geranylgeraniol enhances testosterone production via the cAMP/protein kinase A pathway in testis-derived I-10 tumor cells

Testosterone levels in men decrease with age; this decline has been linked to various diseases and can shorten life expectancy. Geranylgeraniol (GGOH) is an isoprenoid found in plants that plays an important role in several biological processes; however, its role in steroidogenesis is unknown. Here, we report that GGOH enhances the production of testosterone and its precursor progesterone in testis-derived I-10 tumor cells. GGOH induced protein kinase A (PKA) activity and increased cAMP levels and was found to regulate cAMP/PKA signaling by activating adenylate cyclase without altering phosphodiesterase activity. GGOH also stimulated mRNA and protein levels of steroidogenic acute regulatory protein, a downstream effector in the cAMP/PKA pathway. These results demonstrate that GGOH enhances steroidogenesis in testis-derived cells by modulating cAMP/PKA signaling. Our findings have potential applications for the development of therapeutics that increase testosterone levels in aging men.

Increased physical activity has a greater effect than reduced energy intake on lifestyle modification-induced increases in testosterone

Obesity has reached epidemic proportions worldwide. Obesity results in reduced serum testosterone levels, which causes many disorders in men. Lifestyle modifications (increased physical activity and calorie restriction) can increase serum testosterone levels. However, it is unknown whether increased physical activity or calorie restriction during lifestyle modifications has a greater effects on serum testosterone levels. Forty-one overweight and obese men completed a 12-week lifestyle modification program (aerobic exercise training and calorie restriction). We measured serum testosterone levels, the number of steps, and the total energy intake. We divided participants into two groups based on the median change in the number of steps (high or low physical activities) or that in calorie restriction (high or low calorie restrictions). After the program, serum testosterone levels were significantly increased. Serum testosterone levels in the high physical activity group were significantly higher than those in the low activity group. This effect was not observed between the groups based on calorie restriction levels. We found a significant positive correlation between the changes in serum testosterone levels and the number of steps. Our results suggested that an increase in physical activity greatly affected the increased serum testosterone levels in overweight and obese men during lifestyle modification.

Prognostic Value of Flow-Mediated Vasodilation in Brachial Artery and Fingertip Artery for Cardiovascular Events: A Systematic Review and Meta-Analysis

BACKGROUND

Endothelial dysfunction plays a pivotal role in cardiovascular disease progression, and is associated with adverse events. The purpose of this systematic review and meta-analysis was to investigate the prognostic magnitude of noninvasive peripheral endothelial function tests, brachial artery flow-mediated dilation (FMD), and reactive hyperemia--peripheral arterial tonometry (RH-PAT) for future cardiovascular events.

METHODS AND RESULTS

Databases of MEDLINE, EMBASE, and the Cochrane Library were systematically searched. Clinical studies reporting the predictive value of FMD or RH-PAT for cardiovascular events were identified. Two authors selected studies and extracted data independently. Pooled effects were calculated as risk ratio (RR) for continuous value of FMD and natural logarithm of RH-PAT index (Ln_RHI) using random-effects models. Thirty-five FMD studies of 17 280 participants and 6 RH-PAT studies of 1602 participants were included in the meta-analysis. Both endothelial function tests significantly predicted cardiovascular events (adjusted relative risk [95% CI]: 1% increase in FMD 0.88 [0.84-0.91], P<0.001, 0.1 increase in Ln_RHI 0.79 [0.71-0.87], P<0.001). There was significant heterogeneity in the magnitude of the association across studies. The magnitude of the prognostic value in cardiovascular disease subjects was comparable between these 2 methods; a 1 SD worsening in endothelial function was associated with doubled cardiovascular risk.

CONCLUSIONS

Noninvasive peripheral endothelial function tests, FMD and RH-PAT, significantly predicted cardiovascular events, with similar prognostic magnitude. Further research is required to determine whether the prognostic values of these 2 methods are independent of each other and whether an endothelial function-guided strategy can provide benefit in improving cardiovascular outcomes.

Testosterone Concentrations and Cardiovascular Autonomic Neuropathy in Men with Type 1 Diabetes in the Epidemiology of Diabetes Interventions and Complications Study (EDIC)

INTRODUCTION

Previous studies have reported that lower testosterone concentrations are associated with cardiovascular autonomic neuropathy (CAN), a risk factor for cardiovascular events. However, no studies have examined this relationship in men with type 1 diabetes, who are at high risk for CAN.

AIM

The aim of this study was to examine the associations between testosterone concentrations and measures of CAN in a large, well-characterized cohort of men with type 1 diabetes.

METHODS

We conducted an analysis of men in the Diabetes Control and Complications Trial (DCCT), a randomized trial of intensive glucose control, and its observational follow-up the Epidemiology of Diabetes Intervention and Complications (EDIC) Study. Testosterone was measured by liquid chromatography mass spectrometry in stored samples from EDIC follow-up years 10 and 17. Regression models were used to assess the cross-sectional relationships between testosterone and CAN measures.

MAIN OUTCOME MEASURES

The main CAN measure from EDIC follow-up year 17 was a standardized composite of R-R variation with paced breathing < 15, or R-R variation 15-20 combined with either a Valsalva ratio ≤ 1.5 or a decrease in diastolic blood pressure > 10 mm Hg upon standing. Continuous R-R variation and Valsalva ratio were secondary outcomes.

RESULTS

Lower total and bioavailable testosterone concentrations at follow-up years 10 and 17 were not associated with the presence of CAN at year 17. In analyses using Valsalva ratio as a continuous measure, higher total (P = 0.01) and bioavailable testosterone concentrations (P = 0.005) were associated with a higher (more favorable) Valsalva ratio after adjustment for covariates including age, body mass index, smoking status, hypertension, and glycemia.

CONCLUSIONS

Testosterone levels are not associated with CAN among men with type 1 diabetes. Although testosterone is associated with a higher Valsalva ratio, a more favorable indicator, the clinical significance of this association is not known.

A review of the relationships between endogenous sex steroids and incident ischemic stroke and coronary heart disease events

For decades, it has been recognized that men have a higher age-adjusted risk of ischemic cardiovascular (CVD) events compared to women, thus generating hypotheses that sex steroids contribute to CVD risk. Potential mechanisms include genomic and non-genomic effects of sex steroids as well as mediation through classic CVD risk factors and obesity. However, results from randomized studies suggest that sex steroid supplementation in men and women do not result in improved CVD outcomes and may increase CVD risk. In contrast, prospective observations from endogenous sex steroid studies, i.e. among participants not using sex steroids, have suggested the opposite relationship. We reviewed the findings of prospective observational studies in men (17 studies) and women (8 studies) that examined endogenous sex steroids and CVD risk. These studies suggested a lack of association or that lower levels of testosterone or dihydrotestosterone are associated with higher CVD risk in both men and women. Higher, rather than lower, estradiol levels were associated with higher CVD risk in women. There were several significant gaps in the literature. First, it is unclear whether more sensitive measures of sex steroid levels might detect significant differences. Second, there are few prospective studies in women. Similarly, no studies report outcomes for high-risk groups such as African-Americans and Hispanics. Finally, few studies report upon ischemic coronary disease as opposed to ischemic stroke separately, although relationships between sex steroids and CVD may vary by vascular bed. Future investigations need to examine high risk groups and to distinguish between subtypes of CVD.

Low testosterone in men predicts impaired arterial elasticity and microvascular function

BACKGROUND

A low testosterone level in men is associated with increased adiposity, insulin resistance, and dyslipidemia. Whether low testosterone level is associated with arterial stiffness and endothelial and microvascular dysfunction remains unknown and was investigated in this study.

METHODS

Serum testosterone was measured in 237 healthy men aged 50 years (SD 12). Endothelial and microvascular function were assessed as brachial artery flow-mediated dilation (FMD) and digital reactive hyperemia index (RHI), respectively. Arterial stiffness was evaluated by tonometry-derived pulse wave velocity (PWV) and central augmentation index (AIX).

RESULTS

Mean total testosterone level was 16.3 nmol/L (SD 6.11) and 25% of subjects had low levels (<12.0 nmol/L). Testosterone level correlated positively with RHI (r=0.24, p<0.001) and inversely with AIX (r=-0.14, p=0.033) but not with FMD or PWV, indicating impaired microvascular hyperemia and arterial elasticity with lower testosterone levels. After multivariate adjustment for the Framingham Risk Score and weight, testosterone level remained an independent predictor of RHI and AIX (β=0.23, -0.13; p=0.001, 0.04, respectively).

CONCLUSION

In men with few co-morbidities, lower serum testosterone level is associated with microvascular dysfunction and increased pulse wave reflections, mechanisms by which lower testosterone levels may confer increased cardiovascular risk. Whether normalization of low testosterone level improves vascular function needs further investigation.