Impact of testosterone replacement therapy on thromboembolism, heart disease and obstructive sleep apnoea in men

Chronic intermittent hypoxia-induced hypertension: the impact of sex hormones

Obstructive sleep apnea, a common form of sleep-disordered breathing, is characterized by intermittent cessations of breathing that reduce blood oxygen levels and contribute to the development of hypertension. Hypertension is a major complication of obstructive sleep apnea that elevates the risk of end-organ damage. Premenopausal women have a lower prevalence of obstructive sleep apnea and cardiovascular disease than men and postmenopausal women, suggesting that sex hormones play a role in the pathophysiology of sleep apnea-related hypertension. The lack of protection in men and postmenopausal women implicates estrogen and progesterone as protective agents but testosterone as a permissive agent in sleep apnea-induced hypertension. A better understanding of how sex hormones contribute to the pathophysiology of sleep apnea-induced hypertension is important for future research and possible hormone-based interventions. The effect of sex on the pathophysiology of sleep apnea and associated intermittent hypoxia-induced hypertension is of important consideration in the screening, diagnosis, and treatment of the disease and its cardiovascular complications. This review summarizes our current understanding of the impact of sex hormones on blood pressure regulation in sleep apnea with a focus on sex differences.

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.

The complex relation between obstructive sleep apnoea syndrome, hypogonadism and testosterone replacement therapy

Obstructive sleep apnoea syndrome (OSAS) is an under-recognized medical disease. The main risk factors for OSAS are male sex, older age, obesity, and metabolic syndrome, that are also associated with male hypogonadism (MH). Therefore, obesity has been classically identified as the most evident link between OSAS and MH. However, OSAS is per se linked to the development of MH by a combined effect of hypoxia, increased night-time awakenings, reduced sleep efficiency and fragmented sleep. Similarly, MH might represent a risk factor for OSAS, mainly related to sleep disturbances that are frequently associated with low testosterone. Data on testosterone replacement therapy (TRT) in patients with OSAS are limited. Nevertheless, TRT is generally contraindicated by guidelines in the presence of untreated or severe OSAS. TRT might in fact worse OSAS symptoms in different ways. Furthermore, OSAS has been proposed to be a risk factor for secondary polycythaemia and TRT might exacerbate polycythaemia. Therefore, TRT in hypogonadal men affected by untreated OSAS or severe OSAS should be considered with caution and in a personalised way. Nevertheless, the type and dosage of TRT should be considered, as short-term high-dose TRT might worsen OSAS, whereas long-term lower doses could eventually determine a clinical improvement of symptoms of OSAS. Here we reviewed the data on the association between OSAS, MH and TRT, including the opportunity of assessment of patients who develop signs and symptoms of OSAS during TRT by polysomnography.

Involvement of p38 MAPK in Leydig cell aging and age-related decline in testosterone

Introduction

Age-related decline in testosterone is associated with Leydig cell aging with impaired testosterone synthesis in aging. Obesity accelerates the age-related decline in testosterone. However, the mechanisms underlying the Leydig cell aging and the effects of obesity on Leydig cell aging remain unclear.

Method

Natural aging mice and diet-induced obese mice were used to assess the process of testicular Leydig cell senescence with age or obesity. Bioinformatic analysis of the young and aged human testes was used to explore key genes related Leydig cell aging. Leydig cell-specific p38 MAPK knockout (p38LCKO) mice were used to further analyze the roles of p38 MAPK in Leydig cell aging. The levels of testosterone and steroidogenic enzymes, activity of p38 MAPK, aging status of Leydig cells, and oxidative stress and inflammation of testes or Leydig cells were detected by ELISA, immunoblotting, immunofluorescence, and senescence-associated β-galactosidase (SA-β-Gal) staining analysis, respectively.

Result

The serum testosterone level was significantly reduced in aged mice compared with young mice. In the testis of aged mice, the reduced mRNA and protein levels of LHCGR, SRB1, StAR, CYP11A1, and CYP17A1 and the elevated oxidative stress and inflammation were observed. KEGG analysis showed that MAPK pathway was changed in aged Leydig cells, and immunoblotting displayed that p38 MAPK was activated in aged Leydig cells. The intensity of SA-β-Gal staining on Leydig cells and the number of p21-postive Leydig cells in aged mice were more than those of young mice. Similar to aged mice, the testosterone-related indexes decreased, and the age-related indexes increased in the testicular Leydig cells of high fat diet (HFD) mice. Aged p38LCKO mice had higher levels of testosterone and steroidogenic enzymes than those of age-matched wild-type (WT) littermates, with reduced the intensity of SA-β-Gal staining and the expression of p21 protein.

Conclusion

Our study suggested that obesity was an important risk factor for Leydig cell aging. p38 MAPK was involved in Leydig cell aging induced by age and obesity. The inhibition of p38 MAPK could delay Leydig cell aging and alleviate decline in testosterone.

Gender identity and transition: relationships with sleep disorders in US youth

STUDY OBJECTIVES

Transgender or gender-nonconforming (TGNC) identity is associated with higher burden of sleep disorders relative to cisgender identity. However, the role of gender-affirming therapy (GAT) in sleep disorders is poorly understood. This study examined relationships between TGNC identity, transition, and sleep disorders among TGNC and cisgender youth.

METHODS

This retrospective cross-sectional study utilized a large US-based administrative claims database (deidentified Optum Clinformatics Data Mart Database) to identify youth aged 12-25 years who obtained a diagnosis of TGNC identity and those who pursued GAT. Descriptive statistics estimated distributions of demographic and health characteristics by gender identity. Unadjusted and age-adjusted logistic regression models were used to examine associations between TGNC identity, GAT, and sleep disorders.

RESULTS

This study included 1,216,044 youth, of which 2,603 (0.2%) were identified as TGNC. Among the 1,387 TGNC who pursued GAT, 868 and 519 were identified as transmasculine and transfeminine, respectively. Adjusted analysis showed increased odds of insomnia (odds ratio = 5.4, 95% confidence interval 4.7, 6.2), sleep apnea (odds ratio = 3.0, 95% confidence interval 2.3, 4.0), and other sleep disorders (odds ratio = 3.1, 95% confidence interval 2.5, 3.9) in TGNC relative to cisgender youth. Decreased odds of any sleep disorder were observed in the TGNC youth on GAT (odds ratio = 0.5, 95% confidence interval 0.4, 0.7) relative to those not on GAT.

CONCLUSIONS

This study demonstrated a high burden of sleep disorders in TGNC youth in comparison to cisgender. However, GAT may confer a protective effect on sleep disorders among TGNC youth. Longitudinal assessments of sleep disorders prior to and post-GAT are needed to uncover their temporal relationships.

CITATION

Gavidia R, Whitney DG, Hershner S, Selkie EM, Tauman R, Dunietz GL. Gender identity and transition: relationships with sleep disorders in US youth. J Clin Sleep Med. 2022;18(11):2553-2559.

Obesity and male infertility: multifaceted reproductive disruption

Background

The global prevalence of obesity has soared to a concerning height in the past few decades. Interestingly, the global decline in semen quality is a parallel occurrence that urges researchers to evaluate if obesity is among the most essential causatives of male infertility or subfertility.

Main body

Obesity may alter the synchronized working of the reproductive-endocrine milieu, mainly the hypothalamic-pituitary-gonadal (HPG) axis along with its crosstalks with other reproductive hormones. Obesity-mediated impairment in semen parameters may include several intermediate factors, which include physical factors, essentially increased scrotal temperature due to heavy adipose tissue deposits, and systemic inflammation and oxidative stress (OS) initiated by various adipose tissue-derived pro-inflammatory mediators. Obesity, via its multifaceted mechanisms, may modulate sperm genetic and epigenetic conformation, which severely disrupt sperm functions. Paternal obesity reportedly has significant adverse effects upon the outcome of assisted reproductive techniques (ARTs) and the overall health of offspring. Given the complexity of the underlying mechanisms and rapid emergence of new evidence-based hypotheses, the concept of obesity-mediated male infertility needs timely updates and pristine understanding.

Conclusions

The present review comprehensively explains the possible obesity-mediated mechanisms, especially via physical factors, OS induction, endocrine modulation, immune alterations, and genetic and epigenetic changes, which may culminate in perturbed spermatogenesis, disrupted sperm DNA integrity, compromised sperm functions, and diminished semen quality, leading to impaired male reproductive functions.

Sleep Disorders in Patients With Craniopharyngioma: A Physiopathological and Practical Update

Sleep disorders (SDs) represent an important issue in patients with craniopharyngioma (CP). Nearly 70% of these patients complain of sleep-wake cycle alterations and/or excessive diurnal somnolence due to sleep-related breathing disorders, such as obstructive sleep apnea (OSA) and/or central hypersomnia, including secondary narcolepsy. SDs may severely reduce quality of life, increase disease-related cardiorespiratory and cardiovascular morbidity, and finally play a major role in increased long-term mortality reported on patients with CP. A major risk factor for SDs is represented by the hypothalamic syndrome, which may develop because of direct hypothalamic damage by the tumor itself and/or complications of the treatments, neurosurgery and/or radiotherapy, and typically includes permanent neuroendocrine dysfunctions, morbid obesity, and secondary metabolic disorders. Despite increasing attention to SDs in the general population, and in particular to OSA as a risk factor for cardio-metabolic diseases and excessive daytime somnolence, sleep evaluation is still not routinely proposed to patients with CP. Hence, SDs are often underdiagnosed and undertreated. The aim of this paper is to update current knowledge of the pathogenesis and prevalence of SDs in patients with CP and propose practical algorithms for their evaluation and management in clinical practice. Particular attention is paid to screening and diagnostic tools for appropriate characterization of SDs, identification of risk factors, and potential role of hypothalamic sparing surgery in the prevention of morbid obesity and SDs. Available tools in sleep medicine, including lifestyle interventions, drugs, and respiratory devices, are discussed, as well as the importance of optimal hormone replacement and metabolic interventions. Current limits in the diagnosis and treatment of SDs in patients with CP and possible future avenues for research agenda are also considered.

Risk for Venous Thromboembolism in Transgender Patients Undergoing Cross-Sex Hormone Treatment: A Systematic Review

BACKGROUND

Feminizing and masculinizing hormone treatments are established components of management in transgender patients. Exogenous hormones have been associated with hemostatic effects, which are well-studied in cis-gender individuals on hormone replacement therapy (HRT). Unfortunately, comprehensive understanding of their effects on venous thromboembolism (VTE) risk in the transgender population is lacking.

AIM

This manuscript aims to identify the risk of VTE among transgender individuals undergoing cross-sex hormone therapy.

METHODS

A Systematic review of the literature was performed in March 2020 for studies reporting VTE rates in transgender patients undergoing hormone treatment and rates in cis-gender patients on HRT. Data regarding demographics, hormone therapy, and VTE incidence were collected and pooled for analysis.

OUTCOME

The primary outcome of interest was the development of a VTE event in association with concurrent hormone administration.

RESULTS

Overall, 22 studies were included with 11 reporting VTE rates among transgender patients, 6 in cis-female patients, and 5 in cis-male patients. Data from 9,180 transgender patients (6,068 assigned male at birth [AMAB] and 3,112 assigned female at birth [AFAB]) undergoing hormone treatment and 103,713 cis-gender patients (18,748 female and 84,965 male) undergoing HRT were pooled. The incidence of VTE was higher in AMAB patients compared to AFAB patients (42.8 vs 10.8 VTE per 10,000 patient years; P = .02). The rate of VTE incidences in AMAB patients appears similar or higher than the rate demonstrated in cis-females on HRT. VTE incidence in AFAB patients, however, is similar to the published rates in cis-males on HRT.

CLINICAL IMPLICATIONS

AMAB patients on hormone therapy have higher VTE rates than AFAB patients. AMAB and AFAB patients may have similar VTE incidence to cis-female and cis-male patients on hormone replacement therapy, respectively.

STRENGTHS & LIMITATIONS

This is the first study to aggregate and quantify the development of VTE events in association with hormone therapy in transgender patients. It places these values in the context of rates published in more widely studied populations. It is limited by its retrospective data and heterogenic data.

CONCLUSION

Surgical planning regarding perioperative and postoperative VTE prophylaxis or cessation of hormone therapy should take into account each patient's Caprini risk assessment and the nature of each intervention. Kotamarti VS, Greige N, Heiman AJ, et al. Risk for Venous Thromboembolism in Transgender Patients Undergoing Cross-Sex Hormone Treatment: A Systematic Review. J Sex Med 2021;18:1280-1291.

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

BACKGROUND

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

OBJECTIVES

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSION

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

Testosterone replacement therapy and the risk of venous thromboembolism: A systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

The cardiovascular safety of testosterone replacement therapy (TRT) is controversial. While several studies have investigated the association between TRT and the risk of arterial thrombosis, limited information is available regarding its risk of venous thromboembolism (VTE). We aimed to compare the risk of VTE in men randomized to TRT versus placebo or active-comparator in a systematic review.

METHODS

We searched Medline, EMBASE, CINAHL, CENTRAL, and clinical trial registries to identify randomized controlled trials (RCTs) comparing TRT to placebo in men aged ≥18 years. We assessed study quality using the Cochrane Risk of Bias assessment tool and the overall quality of evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. Data were pooled across RCTs using random-effects models.

RESULTS

A total of 13 RCTs (n = 5050) were included in our meta-analysis. In all, 2636 men were randomized to testosterone, and 2414 men to placebo. Sample sizes ranged from 101 to 790 men, and TRT duration from 3 to 36 months. Five studies had a high risk of bias, largely driven by unclear randomization and outcome assessment. When data were pooled across RCTs, testosterone therapy was not associated with VTE compared with placebo (RR: 1.03, 95% CI: 0.49-2.14; I²: 0%; low-quality evidence). Similar estimates were obtained for deep vein thrombosis and pulmonary embolism outcomes.

CONCLUSIONS

Our systematic review suggests that TRT is not associated with an increased risk of VTE. However, estimates were accompanied by a wide 95% CIs, and a clinically important increased risk cannot be ruled out.

Controversies in Testosterone Therapy

INTRODUCTION

Testosterone prescriptions have increased dramatically in recent years, largely because of changes in expert guidelines. Concerns have been raised that testosterone therapy (TTh) may be associated with an increased incidence of conditions such as cardiovascular (CV) disease, thromboembolic events, obstructive sleep apnea (OSA), benign prostatic hyperplasia (BPH), and prostate cancer (PCa) and also may be a beneficial therapy in the management of prediabetes. As such, considerable debate remains regarding which hypogonadal populations are appropriate candidates for TTh.

OBJECTIVES

This systematic review aims to affirm or refute, using the most current evidence, the published concerns surrounding TTh and its potential increased risk of conditions such as CV disease, thromboembolic events, OSA, urolithiasis, BPH, and PCa, as well as its role as a potential tool for managing prediabetes.

METHODS

A systematic review of literature surrounding TTh and its impact on increasing risk for the adverse conditions mentioned previously was performed. 62 publications were selected for inclusion based on their relevance to the effects and risks of TTh. Evidence is current through December 2019.

RESULTS

Evidence demonstrates that positive associations exist between TTh and OSA, erythrocytosis, as well as urolithiasis. TTh may potentially be used to treat hypogonadal men with prediabetes. While low testosterone is positively correlated with adverse CV events, TTh in hypogonadal men either has no effect or decreases such risk. TTh is likely not associated with increased risk of PCa incidence or recurrence.

CONCLUSIONS

Despite historical beliefs that TTh increases the risk of CV disease, thromboembolic events, BPH, and PCa, recent evidence suggests that TTh conveys less risk than previously perceived. While caution should continue to be exercised, evidence suggests that TTh is a reasonable treatment option in many hypogonadal men who were previously excluded from TTh based on risk factors and prior health histories. Twitchell DK, Pastuszak AW, Khera M. Controversies in Testosterone Therapy. Sex Med Rev 2021;9:149-159.

Obstructive Sleep Apnea and Testosterone Therapy

INTRODUCTION

There is persistent speculation that testosterone therapy (TTh) may induce worsening of obstructive sleep apnea (OSA). As both the incidence of OSA and the use of TTh grow more prevalent, it is important to review the current evidence that supports or refutes this relationship.

OBJECTIVES

To review the current literature regarding the relationship between TTh and OSA.

METHODS

A literature search was conducted to identify relevant studies. Search terms included "obstructive sleep apnea" and "testosterone replacement therapy." Titles and abstracts were reviewed for relevance. References from identified articles were searched and included, if appropriate.

RESULTS

The association between TTh and OSA was initially described in a 1978 case report of an individual with worsened nighttime apneas during testosterone administration, a trend seen again in subsequent small case series. In the 1990s, a large retrospective analysis and the first randomized controlled trial on the subject revealed no increased incidence of OSA in individuals on TTh. A randomized controlled trial conducted in 2012 provided a possible explanation to the previously reported discrepancies, describing a time-limited effect, wherein measures of OSA were elevated at seven weeks but were not significantly different at 18 weeks after initiation of TTh. A recent cohort study demonstrated an incidence of OSA in individuals on TTh of 16.5% compared with 12.7% in controls. TTh is thought to affect OSA in several ways. Theories that the anabolic effects of testosterone may decrease airway patency or that testosterone alters sleep architecture have been largely disproven. More likely, testosterone plays a role in altering neural response pathways to hypoxemia.

CONCLUSIONS

TTh likely plays a small role in exacerbating or inducing changes in OSA that may be time limited in nature. Clinicians may choose to exercise caution in prescribing TTh to individuals suffering from severe OSA. Payne K, Lipshultz LI, Hotaling JM, et al. Obstructive Sleep Apnea and Testosterone Therapy. J Sex Med 2021;9:296-303.

Obstructive Sleep Apnea Is Associated With Polycythemia in Hypogonadal Men on Testosterone Replacement Therapy

BACKGROUND

Polycythemia (erythrocytosis) is a known side effect of testosterone (T) replacement therapy (TRT) and appears to correlate with maximum T levels. There is also a well-established association between obstructive sleep apnea (OSA) and the development of polycythemia, which confers additional long-term cardiovascular morbidity. Synergy between TRT and OSA in the development of polycythemia remains poorly understood.

AIM

The objective of this study was to retrospectively assess the relationship of OSA and secondary polycythemia in hypogonadal men receiving TRT.

METHODS

We performed a retrospective chart review of all men treated by a single provider from 2015 to 2019 for the diagnosis of hypogonadism. Patients who developed a hematocrit of 52% or greater were classified as having polycythemia. OSA was identified via clinical documentation or use of nocturnal continuous positive airway pressure. Demographics, laboratory values, treatment details, and comorbidities were recorded. Data were reported as mean ± SD for parametric variables and median [interquartile range] for non-parametric values.

OUTCOME

The primary outcome of this study was the association between OSA and polycythemia in hypogonadal men on TRT.

RESULTS

474 men were included in this study. 62/474 (13.1%) men met the criteria for the diagnosis of polycythemia with a median hematocrit of 53.6 [interquartile range 52.6, 55.5]. Univariate analysis demonstrated a strong positive association between polycythemia and the concomitant diagnosis of OSA in hypogonadal men (P = .002). Even after correcting for age, body mass index (BMI), and peak T levels in the multivariate analysis (P = .01), this relationship remained significant with an odds ratio of 2.09 [95% CI 1.17, 3.76]. 37 men on TRT with polycythemia and OSA were included in the final cohort with a mean age of 59.2 ± 11.4 years, mean BMI of 32.4 ± 6.0, and median time from TRT initiation to polycythemia diagnosis of 3 years. All patients diagnosed with OSA were prescribed continuous positive airway pressure with poor compliance noted in 52.8% of men. 37.8% were managed via phlebotomy and 59.5% were managed via dose de-escalation of TRT. In hypogonadal men on TRT with polycythemia, BMI was the only risk factor strongly associated with OSA (P = .013).

CLINICAL TRANSLATION

In hypogonadal men (particularly those with elevated BMI) on TRT who develop secondary polycythemia, a diagnosis of OSA should be strongly considered.

STRENGTHS & LIMITATIONS

This is a single provider retrospective study and further studies are needed to assess generalizability.

CONCLUSIONS

In this retrospective single-center cohort, the development of polycythemia in hypogonadal men on TRT was associated with an increased prevalence of OSA. Lundy SD, Parekh NV, Shoskes DA. Obstructive Sleep Apnea Is Associated With Polycythemia in Hypogonadal Men on Testosterone Replacement Therapy. J Sex Med 2020;17:1297-1303.

The role of bioidentical hormone replacement therapy in anti-aging medicine: a review of the literature

The changes in skin and overall appearance that occur with increasing age can be partly attributed to declining hormone levels. While hormonal deficiencies are most commonly associated with postmenopausal females, males are also subject to age-related testosterone decline and may benefit from replacement of deficient hormones. However, great disparities exist between the recommendations of scientific societies and actual use of hormone supplements in aging patients. The purpose of this literature review is to discuss the role of hormones in the aging process of the skin, explain the safety profile of hormone replacement therapy, specifically discussing the superiority of bioidentical hormones, and highlight the benefits of hormone replacement in anti-aging of the skin. In summary, this literature review suggests that hormone replacement with bioidentical hormones is a safe and effective way to prevent skin aging.

Systemic effects of the hormonal treatment of male hypogonadism with preliminary indications for the management of COVID-19 patients

Male hypogonadism, defined as an inadequate production of testosterone (T), is associated with a greater morbidity and mortality. Epidemiological studies identified T deficiency as a risk factor for cardiovascular disease. Also, low serum T levels impact on glucose homeostasis through a worse glucose uptake, utilization, and disposal, and the general negative impact on metabolism. The aim of this review is to provide a comprehensive and updated overview of the effects of T replacement therapy on metabolic and cardiovascular systems and prostate tissue in patients with hypogonadism, including molecular mechanisms through which T exerts its actions. Furthermore, recent findings on novel coronavirus disease (COVID-19) epidemiology have shown a greater mortality in male compared with female patients and a role of T in promoting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection of the host cells has been demonstrated. Hence, the secondary aim of this review is to provide preliminary indications on the management in patients with COVID-19.

A Mechanistic and Pathophysiological Approach for Stroke Associated with Drugs of Abuse

Drugs of abuse are associated with stroke, especially in young individuals. The major classes of drugs linked to stroke are cocaine, amphetamines, heroin, morphine, cannabis, and new synthetic cannabinoids, along with androgenic anabolic steroids (AASs). Both ischemic and hemorrhagic stroke have been reported due to drug abuse. Several common mechanisms have been identified, such as arrhythmias and cardioembolism, hypoxia, vascular toxicity, vascular spasm and effects on the thrombotic mechanism, as causes for ischemic stroke. For hemorrhagic stroke, acute hypertension, aneurysm formation/rupture and angiitis-like changes have been implicated. In AAS abuse, the effect of blood pressure is rather substance specific, whereas increased erythropoiesis usually leads to thromboembolism. Transient vasospasm, caused by synthetic cannabinoids, could lead to ischemic stroke. Opiates often cause infective endocarditis, resulting in ischemic stroke and hypereosinophilia accompanied by pyogenic arthritis, provoking hemorrhagic stroke. Genetic variants are linked to increased risk for stroke in cocaine abuse. The fact that case reports on cannabis-induced stroke usually refer to the young population is very alarming.

Association of genetically predicted testosterone with thromboembolism, heart failure, and myocardial infarction: mendelian randomisation study in UK Biobank

OBJECTIVE

To determine whether endogenous testosterone has a causal role in thromboembolism, heart failure, and myocardial infarction.

DESIGN

Two sample mendelian randomisation study using genetic variants as instrumental variables, randomly allocated at conception, to infer causality as additional randomised evidence.

SETTING

Reduction by Dutasteride of Prostate Cancer Events (REDUCE) randomised controlled trial, UK Biobank, and CARDIoGRAMplusC4D 1000 Genomes based genome wide association study.

PARTICIPANTS

3225 men of European ancestry aged 50-75 in REDUCE; 392 038 white British men and women aged 40-69 from the UK Biobank; and 171 875 participants of about 77% European descent, from CARDIoGRAMplusC4D 1000 Genomes based study for validation.

MAIN OUTCOME MEASURES

Thromboembolism, heart failure, and myocardial infarction based on self reports, hospital episodes, and death.

RESULTS

Of the UK Biobank participants, 13 691 had thromboembolism (6208 men, 7483 women), 1688 had heart failure (1186, 502), and 12 882 had myocardial infarction (10 136, 2746). In men, endogenous testosterone genetically predicted by variants in the JMJD1C gene region was positively associated with thromboembolism (odds ratio per unit increase in log transformed testosterone (nmol/L) 2.09, 95% confidence interval 1.27 to 3.46) and heart failure (7.81, 2.56 to 23.8), but not myocardial infarction (1.17, 0.78 to 1.75). Associations were less obvious in women. In the validation study, genetically predicted testosterone (based on JMJD1C gene region variants) was positively associated with myocardial infarction (1.37, 1.03 to 1.82). No excess heterogeneity was observed among genetic variants in their associations with the outcomes. However, testosterone genetically predicted by potentially pleiotropic variants in the SHBG gene region had no association with the outcomes.

CONCLUSIONS

Endogenous testosterone was positively associated with thromboembolism, heart failure, and myocardial infarction in men. Rates of these conditions are higher in men than women. Endogenous testosterone can be controlled with existing treatments and could be a modifiable risk factor for thromboembolism and heart failure.

Obesity, Male Reproductive Function and Bariatric Surgery

Overweight and obesity are associated with several chronic complications, such as type 2 diabetes, arterial hypertension and atherosclerotic cardiovascular diseases, with relevant consequences for patients and public health systems. Reproductive function abnormalities, such as obesity-related secondary hypogonadism, erectile dysfunction and infertility, represent other abnormalities negatively affecting the quality of life of men suffering from obesity but, despite their high prevalence, these are often understated because of a general lack of awareness in clinical practice. Obesity and gonadal function are closely related, with obesity being associated with hypogonadism that is reversed by body weight reduction thus ameliorating reproductive and sexual health. Clinical studies specifically evaluating the impact of non-surgical weight loss on testosterone levels sometimes showed conflicting results, whereas extensive literature has demonstrated that weight loss after bariatric surgery is correlated with an increase in testosterone levels greater than that obtained with only lifestyle interventions, suggesting the role of surgery also for the treatment of hypogonadism in obese male. However, studies concerning the consequences of bariatric surgery on overall reproductive function in the male, including also sexual activity and fertility, are limited and data regarding long-term effects are lacking. Here we present a brief review summarizing the evidence regarding the interplay between obesity and reproductive abnormalities in the obese male, together with the role of bariatric surgery for the treatment of these complications, describing both the positive effects and the limitations of this procedure.

Activity-Based Physical Rehabilitation with Adjuvant Testosterone to Promote Neuromuscular Recovery after Spinal Cord Injury

Neuromuscular impairment and reduced musculoskeletal integrity are hallmarks of spinal cord injury (SCI) that hinder locomotor recovery. These impairments are precipitated by the neurological insult and resulting disuse, which has stimulated interest in activity-based physical rehabilitation therapies (ABTs) that promote neuromuscular plasticity after SCI. However, ABT efficacy declines as SCI severity increases. Additionally, many men with SCI exhibit low testosterone, which may exacerbate neuromusculoskeletal impairment. Incorporating testosterone adjuvant to ABTs may improve musculoskeletal recovery and neuroplasticity because androgens attenuate muscle loss and the slow-to-fast muscle fiber-type transition after SCI, in a manner independent from mechanical strain, and promote motoneuron survival. These neuromusculoskeletal benefits are promising, although testosterone alone produces only limited functional improvement in rodent SCI models. In this review, we discuss the (1) molecular deficits underlying muscle loss after SCI; (2) independent influences of testosterone and locomotor training on neuromuscular function and musculoskeletal integrity post-SCI; (3) hormonal and molecular mechanisms underlying the therapeutic efficacy of these strategies; and (4) evidence supporting a multimodal strategy involving ABT with adjuvant testosterone, as a potential means to promote more comprehensive neuromusculoskeletal recovery than either strategy alone.