Outcomes of testosterone therapy in men with testosterone deficiency (TD): part II

[Practical recommendations for the management of testosterone deficiency]

OBJECTIVES

The Francophone Society of Sexual Medicine (SFMS) and the Andrology and Sexual Medicine Committee (CAMS) of the French Association of Urology (AFU) have brought together a panel of experts to develop French recommendations for the management of testosterone deficiency (TD).

METHODS

Systematic review of the literature between 01/2000 and 07/2019. Use of the method of recommendations for clinical practice (RPC) and the AGREE II grid.

RESULTS

TD is defined as the association of clinical signs and symptoms suggestive of TD with a decrease in testosterone levels or serum androgen activity. Diagnosis requires a T lower than the reference values in young men on 2 successive assays. Sexual disorders are often at the forefront, and concern the whole male sexual function (desire, arousal, pleasure and orgasm). The most evocative symptoms are: decrease in sexual desire, disappearance of nocturnal erections, fatigue, loss of muscle strength. Overweight, depressed mood, anxiety, irritability and malaise are also frequently found. TD is more common in cases of metabolic, cardiovascular, chronic, andrological diseases, and in cases of corticosteroid, opioid, antipsychotic, anticonvulsant, antiretroviral, or cancer treatment. Since SHBG is frequently abnormal, we recommend that free or bioavailable T is preferred over total T. The treatment of TD requires a prior clinical (DRE, breast examination) and biological (PSA, CBC) assessment. Contraindications to T treatment are: progressive prostate or breast cancer, severe heart failure or recent cardiovascular event, polycytemia, complicated BPH, paternity project. It is possible in cases of sleep apnea syndrome, psychiatric history, stable heart disease, prostate cancer under active surveillance and after one year of complete remission of a low or intermediate risk localized prostate cancer treated in a curative manner. It includes long-term testosterone supplementation and life-style counseling. Treatment is monitored at 3, 6, 12 months and annually thereafter. It is clinical (annual DRE) and biological (total T, PSA, CBC), the most frequent side effect being polyglobulia.

CONCLUSION

These recommendations should help improve the management of TD.

Metabolic effects of cross-sex hormone therapy in transgender individuals in Taiwan

BACKGROUND

Transgender individuals often require gender-affirming interventions, such as endogenous sex hormone inhibition or gender-affirming hormone therapy (HT), while there is discordance between their body and gender identity. However, a recent study found that the incidence of cardiovascular events is higher in transgender patients receiving cross-sex HT. The aim of this study was to investigate the metabolic effects of an altered sex hormone profile.

METHODS

This retrospective study, conducted in a referral center in Northern Taiwan, analyzed metabolic changes over time in 65 trans masculine and 45 trans feminine persons. The transgender individuals were examined at 4 time points: before the gender affirming HT, as well as 3, 6, and 12 months following treatment.

RESULTS

Compared with baseline measurements, the trans masculine patients showed significant increases in body mass index (BMI) (22.6 ± 0.3 vs 23.3 ± 0.4 kg/m2; p < 0.001; t = 3M), low-density lipoprotein cholesterol (124.3 ± 3.7 vs 131.3 ± 3.9 mg/dL; p = 0.03; t = 12M), creatinine (0.75 ± 0.01 vs 0.83 ± 0.14 mg/dL; p < 0.001; t = 12M), and hemoglobin (13.5 ± 0.7 vs 15.2 ± 0.2 g/dL; p < 0.001; t = 12M), as well as decreased high-density lipoprotein cholesterol (57 ± 2.1 vs 51 ± 2.0 mg/dL; p < 0.001; t = 12M). The trans feminine patients had reduced low-density lipoprotein cholesterol (104.2 ± 3.2 vs 100.8 ± 3.5 mg/dL; p = 0.05; t = 3M), hemoglobin (14.0 ± 0.1 vs 13.5 ± 0.1 g/dL; p = 0.008; t = 12M), and creatinine (0.82 ± 0.01 vs 0.79 ± 0.14 mg/dL; p < 0.001; t = 3M) compared with baseline data. In addition, most of these metabolic effects persisted during the follow-up period.

CONCLUSION

This observational, retrospective study revealed that gender-affirming HT increased the relative cardiovascular risk in trans masculine individuals.

A National Analysis of Temporal Changes in Prescribing of Testosterone Replacement Therapy Considering Methods of Delivery and Government Regulation

Purpose

Testosterone replacement therapy (TRT) is commonly used for various causes of androgen deficiency and subsidized by the Pharmaceutical Benefits Scheme (PBS) in Australia when appropriate. In response to a sharp increase in the prescribing of subsidized TRT, the Australian government instituted new, stricter prescription criteria in April 2015. We aim to demonstrate longitudinal changes in the prescription patterns of subsidized TRT over time.

Materials and Methods

The publicly available PBS database was accessed for TRT prescription data between 1992–2018. Population estimate data was collected from the Australian Bureau of Statistics for population-adjustment. Data analysis was performed according to class and specific formulation of TRT. Total and population-adjusted trends were considered, as was indexation to 2015 when restrictions were implemented.

Results

Longitudinal trends in subsidized TRT prescription demonstrated a progressive overall increase since 2000, according to total prescriptions and population-adjusted estimates, with greater use of topical formulations (gel, patch, cream/spray) and injections. Since 2015, a 37% decline in total population-adjusted prescriptions was observed (1,399–883 per 100,000 persons). Since 2015, relatively increased use of injections (50%) and 1% gel (30%) comprise the majority of contemporary TRT. Annual financial burden due to TRT was $AU16,768 per 100,000 persons prior to 2000 (mean cost 1992–2000), increasing to $AU112,539 in 2018 (due to use of injections). The rate of change in costs slowed after the restrictions were introduced in 2015.

Conclusions

The restrictions in subsidized TRT eligibility enforced by the PBS have reduced overall TRT prescriptions and slowed the cumulative financial burden.

Short-term effect of pharmacologically induced alterations in testosterone levels on common blood biomarkers in a controlled healthy human model

Testosterone deficiency in males is associated with serious comorbidities such as cardiovascular disease, diabetes type two, and also an increased risk of premature death. The pathogenetic mechanism behind this association, however, has not yet been clarified and is potentially bidirectional. The aim of this clinical trial was to gain insight into the short-term effect of changes in testosterone on blood analytes in healthy young men. Thirty healthy young male volunteers were recruited and monitored in our designed human model. Blood sampling was performed prior to and 3 weeks after pharmacological castration with a gonadotropin-releasing hormone antagonist. Subsequently, testosterone replacement with 1000 mg testosterone undecanoate was given and additional blood samples were collected 2 weeks later. The alterations in the levels of 37 routine biomarkers were statistically analysed. Eight biomarkers changed significantly in a similar manner as testosterone between the time points (e.g. prostate specific antigen, creatinine and magnesium), whereas seven other markers changed in the inverse manner as testosterone, including sexual hormone-binding globulin, urea, aspartate aminotransferase and alanine aminotransferase. Most of our results were supported by data from other studies. The designed controlled human model yielded changes in known biomarkers suggesting that low testosterone has a negative effect on health in young healthy men.

A cross-sectional survey of adrenal steroid hormones among overweight/obese boys according to puberty stage

BACKGROUND

Obesity is associated with many chronic diseases including cortisol rhythm disorder and low testosterone. Furthermore, studies on obese children are quite limited and no concordance results have been obtained, especially for boys in puberty. Moreover, the sample sizes of previous studies were small, and were not representative.

METHODS

We conducted a cross-sectional survey including 1148 boys aged 6-14 years, they were divided into overweight/obesity (OW/OB) group and normal weight (NW) group. Puberty status was assessed according to Tanner scale and testicular volume. Serum levels of pregnenolone, 17-OH progesterone, corticosterone, dehydroepiandrosterone (DHEA), and androstenedione were detected by LC-MS. Serum free testosterone and sex hormone-binding globulin (SHBG) levels were measured by chemiluminescence immunoassay.

RESULTS

The 17-OH progesterone, DHEA, androstenedione and free testosterone levels of OW/OB boys at prepubertal stage or at the age 6 = < 10 years group were higher than those of the NW boys (all the P values were < 0.01). Furthermore, androstenedione and free testosterone levels were lower in OW/OB boys at late puberty, and the trend continued at the post pubertal stage for FT (P < 0.01-0.05). DHEA, androstenedione, and FT levels persisted to be higher at the 10~ < 12 years in OW/OB boys but not for 17-OH progesterone. FT level was lower in the OW/OB group at the 12~ < 15 years group. The SHBG levels in the OW/OB boys were lower than those in the NW ones at the 6~12 years group, and prepubertal to early pubertal stage.

CONCLUSIONS

Premature adrenarche is more likely in OW/OB boys. More attention should be given to the lower androgen levels of OW/OB boys at late pubertal and post pubertal stages.

The complex association between metabolic syndrome and male hypogonadism

BACKGROUND

The complex association between metabolic syndrome (MetS) and male hypogonadism is well established. A number of observational studies show that low testosterone is associated with insulin resistance and an increased risk for diabetes mellitus and MetS in men.

AIMS

To elucidate the association between MetS and male hypogonadism, present epidemiological data on the co-existence of the two comorbidities, enlighten the underlying pathophysiology and appraise the effects of testosterone supplementation therapy (TTh) and lifestyle modifications on MetS and body composition in men.

MATERIALS AND METHODS

Systematic search to PubMed and Medline databases for publications reporting data on association between MetS and male hypogonadism.

RESULTS

Both MetS and male hypogonadism have a high prevalence in the general population and are frequently co-existing e.g. in males with diabetes. Accumulating evidence from animal and human studies suggests that MetS is involved in the pathogenesis of hypogonadism in males as well as the other way around. On the other hand, there is evidence for a favorable effect of testosterone supplementation in testosterone deficient men with MetS and/or diabetes mellitus.

CONCLUSIONS

Studies with superior methodological characteristics are needed in order to establish a role for testosterone supplementation in men with MetS and/or diabetes mellitus.

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.

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

Objectives:

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

Patients and Methods:

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

Results:

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

Conclusion:

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

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

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

Gonadal function is associated with cardiometabolic health in pre-pubertal boys with Klinefelter syndrome

The most common sex chromosome aneuploidy, Klinefelter syndrome (KS), is associated with primary gonadal failure and increased morbidity and mortality from cardiometabolic disorders in adulthood. Children with KS also have a high prevalence of metabolic syndrome (MetS) features. To assess the relationship of gonadal and cardiometabolic function in children with KS, we evaluated serum hormones [gonadotropins, inhibin B (INHB), anti-mullerian hormone (AMH), total testosterone (TT)], and features of MetS (waist circumference, fasting lipid panel, fasting blood glucose (FBG), and blood pressure) in 93 pre-pubertal boys with KS age 4-12 years (mean 7.7 ± 2.5 years). The cohort was grouped by age and tanner stage, and biomarkers were compared to normal ranges. A total of 80% of this pre-pubertal cohort had ≥1 feature of metabolic syndrome (MetS) and 11% had ≥3 features of MetS. Risk of MetS was independent of age and body mass index. Sertoli cell dysfunction was common with 18% having an INHB below the normal range. A low INHB was associated with higher FBG, triglycerides, LDL, and lower HDL (p < 0.05). An INHB <50 ng/dL yielded a sensitivity of 83% and a specificity of 79% for having ≥3 features of MetS. INHB and AMH positively correlated with each other (p < 0.001), and high AMH was protective of MetS. TT was below the lower limit of normal in 49% of subjects, with mean values significantly lower than expected (3.3 ng/dL vs. 4.9 ng/dL, p < 0.0001), however, no convincing relationship between TT and MetS was seen. In conclusion, gonadal and cardiometabolic dysfunction are prevalent in pre-pubertal boys with KS. Although the relationship of testosterone deficiency and MetS is well-known, this study is the first to report an association between impaired Sertoli cell function and cardiometabolic risk.

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

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

Effects of Tribulus terrestris saponins on exercise performance in overtraining rats and the underlying mechanisms

The objective of this study was to determine the effects of Tribulus terrestris L. (TT) saponins on exercise performance and the underlying mechanisms. A rat overtraining model was established and animals were treated with TT extracts (120 mg/kg body mass) 30 min before each training session. Serum levels of testosterone and corticosterone and levels of androgen receptor (AR) and insulin growth factor-1 receptor (IGF-1R) in the liver, gastrocnemius, and soleus were determined by ELISA and Western blot. Treatment of rats with TT saponins significantly improved the performance of the overtraining rats, reflected by the extension of time to exhaustion, with a concomitant increase in body mass, relative mass, and protein levels of gastrocnemius. Overtraining alone induced a significant decrease in the serum level of testosterone. In contrast, treatment with TT saponins dramatically increased the serum level of testosterone in overtraining rats to about 150% of control and 216% of overtraining groups, respectively. In addition, TT saponins resulted in a further significant increase in AR in gastrocnemius and significantly suppressed the overtraining-induced increase in IGF-1R in the liver. These results indicated that TT saponins increased performance, body mass, and gastrocnemius mass of rats undergoing overtraining, which might be attributed to the changes in androgen-AR axis and IGF-1R signaling.

Testosterone Replacement Therapy: The Emperor's New Clothes

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

METABOLIC EFFECTS OF HORMONE THERAPY IN TRANSGENDER PATIENTS

OBJECTIVE

Transgender patients may seek hormone therapy to induce physical changes to simulate their expressed or experienced gender. However, many providers are uncomfortable prescribing transgender hormones due to fears over safety. The goal of this study was to determine if transgender hormone therapy with estrogen and spironolactone for male-to-female (MtF) patients or with testosterone for female-to-male (FtM) patients had adverse anthropomorphic or metabolic effects.

METHODS

This retrospective chart review study analyzed changes over time for 33 MtF and 19 FtM endocrine clinic patients at an academic endocrine practice with follow-up for up to 18 months after hormone initiation.

RESULTS

Compared to baseline labs obtained prior to the initiation of hormone therapy, significant changes for the MtF cohort included an increase in high-density lipoprotein (HDL) and decrease in creatinine; however, triglycerides did not show a statistically significant change. In the FtM cohort, there were significant increases in body mass index, creatinine, hemoglobin, and hematocrit. Although statistically significant, these changes were minimal for both cohorts.

CONCLUSION

In our practice, hormone therapy was found to be safe in this retrospective study.

METABOLIC EFFECTS OF HORMONE THERAPY IN TRANSGENDER PATIENTS

OBJECTIVE

Transgender patients may seek hormone therapy to induce physical changes to simulate their expressed or experienced gender. However, many providers are uncomfortable prescribing transgender hormones due to fears over safety. The goal of this study was to determine if transgender hormone therapy with estrogen and spironolactone for male-to-female (MtF) patients or with testosterone for female-to-male (FtM) patients had adverse anthropomorphic or metabolic effects.

METHODS

This retrospective chart review study analyzed changes over time for 33 MtF and 19 FtM endocrine clinic patients at an academic endocrine practice with follow-up for up to 18 months after hormone initiation.

RESULTS

Compared to baseline labs obtained prior to the initiation of hormone therapy, significant changes for the MtF cohort included an increase in high-density lipoprotein (HDL) and decrease in creatinine; however, triglycerides did not show a statistically significant change. In the FtM cohort, there were significant increases in body mass index, creatinine, hemoglobin, and hematocrit. Although statistically significant, these changes were minimal for both cohorts.

CONCLUSION

In our practice, hormone therapy was found to be safe in this retrospective study.

The complex and multifactorial relationship between testosterone deficiency (TD), obesity and vascular disease

Testosterone deficiency (TD) is a well-established and recognized medical condition that contributes to several co-morbidities, including metabolic syndrome, visceral obesity and cardiovascular disease (CVD). More importantly, obesity is thought to contribute to TD. This complex bidirectional interplay between TD and obesity promotes a vicious cycle, which further contributes to the adverse effects of TD and obesity and may increase the risk of CVD. Testosterone (T) therapy for men with TD has been shown to be safe and effective in ameliorating the components of the metabolic syndrome (Met S) and in contributiong to increased lean body mass and reduced fat mass and therefore contributes to weight loss. We believe that appropriate T therapy in obese men with TD is a novel medical approach to manage obesity in men with TD. Indeed, other measures of lifestyle and behavioral changes can be used to augment but not fully replace this effective therapeutic approach. It should be noted that concerns regarding the safety of T therapy remain widely unsubstantiated and considerable evidence exists supporting the benefits of T therapy. Thus, it is paramount that clinicians managing obese men with TD be made aware of this novel approach to treatment of obesity. In this review, we discuss the relationship between TD and obesity and highlight the contemporary advancement in management of obesity with pharmacological and surgical approaches, as well as utilization of T therapy and how this intervention may evolve as a novel approach to treatment of obesity in men with TD .

Cardiovascular risks and elevation of serum DHT vary by route of testosterone administration: a systematic review and meta-analysis

BACKGROUND

Potential cardiovascular (CV) risks of testosterone replacement therapy (TRT) are currently a topic of intense interest. However, no studies have addressed CV risk as a function of the route of administration of TRT.

METHODS

Two meta-analyses were conducted, one of CV adverse events (AEs) in 35 randomized controlled trials (RCTs) of TRT lasting 12 weeks or more, and one of 32 studies reporting the effect of TRT on serum testosterone and dihydrotestosterone (DHT).

RESULTS

CV risks of TRT: Of 2,313 studies identified, 35 were eligible and included 3,703 mostly older men who experienced 218 CV-related AEs. No significant risk for CV AEs was present when all TRT administration routes were grouped (relative risk (RR) = 1.28, 95% confidence interval (CI): 0.76 to 2.13, P = 0.34). When analyzed separately, oral TRT produced significant CV risk (RR = 2.20, 95% CI: 1.45 to 3.55, P = 0.015), while neither intramuscular (RR = 0.66, 95% CI: 0.28 to 1.56, P = 0.32) nor transdermal (gel or patch) TRT (RR = 1.27, 95% CI: 0.62 to 2.62, P = 0.48) significantly altered CV risk. Serum testosterone/DHT following TRT: Of 419 studies identified, 32 were eligible which included 1,152 men receiving TRT. No significant difference in the elevation of serum testosterone was present between intramuscular or transdermal TRT. However, transdermal TRT elevated serum DHT (5.46-fold, 95% CI: 4.51 to 6.60) to a greater magnitude than intramuscular TRT (2.20-fold, 95% CI: 1.74 to 2.77).

CONCLUSIONS

Oral TRT produces significant CV risk. While no significant effects on CV risk were observed with either injected or transdermal TRT, the point estimates suggest that further research is needed to establish whether administration by these routes is protective or detrimental, respectively. Differences in the degree to which serum DHT is elevated may underlie the varying CV risk by TRT administration route, as elevated serum dihydrotestosterone has been shown to be associated with CV risk in observational studies.

Adverse health effects of testosterone deficiency (TD) in men

Testosterone and its metabolite, 5α-dihydrotestosterone are critical metabolic and vascular hormones, which regulate a host of biochemical pathways including carbohydrate, lipid and protein metabolism and modulate vascular function. Testosterone deficiency (TD) is a well-recognized medical condition with important health implications. TD is associated with a number of co-morbidities including increased body weight, adiposity and increased waist circumference, insulin resistance (IR) and type 2 diabetes mellitus (T2DM), hypertension, inflammation, atherosclerosis and cardiovascular disease, erectile dysfunction (ED) and increased incidence of mortality. In this review, we summarize the data in the literature on the prevalence of TD and its association with the various co-morbidities and suggest that T therapy is necessary to improve health outcomes in men with TD.