Effects of long-term testosterone therapy on patients with "diabesity": results of observational studies of pooled analyses in obese hypogonadal men with type 2 diabetes

Exogenous Testosterone, Aging, and Changes in Behavioral Response of Gonadally Intact Male Mice

This study tested the hypothesis that aging significantly affects the influence of exogenous testosterone on neurobehavior in gonadally intact male mice. Groups of prepubertal and aged male mice received daily vehicle or testosterone propionate (TP; 2.5 or 5.0 mg/kg intraperitoneal [i.p.]) for 21 days. Behaviors were assessed on days 1 and 21. Weight gain was significant in prepubertal mice. Locomotion and rearing increased in prepubertal mice after first dose and decreased after last dose of TP. Rearing was suppressed in aged mice throughout. Suppression of grooming occurred in both age groups at day 21. Significant increase in working memory in both age groups was seen in the radial-arm maze (at specific doses) and in prepubertal mice in the Y-maze. Elevated plus maze test showed mixed anxiolytic/anxiogenic effects. Aged mice had higher serum testosterone. In conclusion, age is an important determinant for the influence of exogenous testosterone on behavior in gonadally intact male mice.

Serum testosterone, testosterone replacement therapy and all-cause mortality in men with type 2 diabetes: retrospective consideration of the impact of PDE5 inhibitors and statins

BACKGROUND

Low testosterone levels occur in over 40% of men with type 2 diabetes mellitus (T2DM) and have been associated with increased mortality. Testosterone replacement together with statins and phosphodiesterase 5 inhibitors (PDE5I) are widely used in men with T2DM.

PURPOSE

To determine the impact of testosterone and testosterone replacement therapy (TRT) on mortality and assess the independence of this effect by adjusting statistical models for statin and PDE5I use.

METHODS

We studied 857 men with T2DM screened from five primary care practices during April 2007-April 2009. Of the 857 men, 175/637 men with serum total testosterone ≤ 12 nmol/l or free testosterone (FT) ≤ 0.25 nmol/l received TU for a mean of 3.8 ± 1.2 (SD) years. PDE5I and statins were prescribed to 175/857 and 662/857 men respectively. All-cause mortality was the primary end-point. Cox regression models were used to compare survival in the three testosterone level/treatment groups, the analysis adjusted for age, statin and PDE5I use, BMI, blood pressure and lipids.

RESULTS

Compared with the Low T/untreated group, mortality in the Normal T/untreated (HR: 0.62, CI: 0.41-0.94) or Low T/treated (HR: 0.38, CI: 0.16-0.90) groups was significantly reduced. PDE5I use was significantly associated with reduced mortality (HR: 0.21, CI: 0.066-0.68). After repeating the Cox regression in the 682 men not given a PDE5I, mortality in the Normal T/untreated and Low T/treated groups was significantly lower than that in the reference Low T/untreated group. Mortality in the PDE5I/treated was significantly reduced compared with the PDE5I/untreated group (OR: 0.06, CI: 0.009-0.47).

CONCLUSIONS

Testosterone replacement therapy is independently associated with reduced mortality in men with T2DM. PDE5I use, included as a confounding factor, was associated with decreased mortality in all patients and, those not on TRT, suggesting independence of effect. The impact of PDE5I treatment on mortality (both HR and OR < 0.25) needs confirmation by independent studies.

THERAPY OF ENDOCRINE DISEASE: Testosterone supplementation and body composition: results from a meta-analysis study

OBJECTIVE

The role of testosterone (T) in regulating body composition is conflicting. Thus, our goal is to meta-analyse the effects of T supplementation (TS) on body composition and metabolic outcomes.

METHODS

All randomized controlled trials (RCTs) comparing the effect of TS on different endpoints were considered.

RESULTS

Overall, 59 trials were included in the study enrolling 3029 and 2049 patients in TS and control groups respectively. TS was associated with any significant modification in body weight, waist circumference and BMI. Conversely, TS was associated with a significant reduction in fat and with an increase in lean mass as well as with a reduction of fasting glycaemia and insulin resistance. The effect on fasting glycaemia was even higher in younger individuals and in those with metabolic diseases. When only RCTs enrolling hypogonadal (total T <12  mol/l) subjects were considered, a reduction of total cholesterol as well as triglyceride (TGs) levels were also detected. Conversely, an improvement in HDL cholesterol levels as well as in both systolic and diastolic blood pressure was not observed.

CONCLUSION

Our data suggest that TS is able to improve body composition and glycometabolic profile particularly in younger subjects and in those with metabolic disturbances. Specifically designed studies are urgently needed to confirm this point.

Effects of continuous long-term testosterone therapy (TTh) on anthropometric, endocrine and metabolic parameters for up to 10 years in 115 hypogonadal elderly men: real-life experience from an observational registry study

Subnormal levels of testosterone are associated with significant negative health consequences, with higher risks of all-cause and cardiovascular mortality. The numbers of studies reporting on the benefits of normalisation of testosterone is increasing but longer-term data on (elderly) men receiving testosterone treatment are almost nonexistent. In this single-centre, cumulative, prospective, registry study, 115 hypogonadal men (mean age 59.05 years) received injections with testosterone undecanoate in 12-week intervals for up to 10 years. Waist circumference, body weight and mean BMI dropped progressively with statistical significance versus previous year for 7 years and, respectively, 8 years for weight and body mass index. Similarly, fasting glucose displayed a significant decrease after the first year continuing to decrease thereafter. A decline in HbA1c , from 6.4% to 5.6% (mean <6%), was observed from year 2 on, together with a decrease in the ratio of triglycerides:high-density lipoprotein (HDL), a surrogate marker of insulin resistance, with an increase in HDL levels. The total cholesterol:HDL ratio and non-HDL cholesterol declined significantly. A decrease was also observed in systolic and diastolic blood pressure, with a decrease in levels of the inflammation marker C-reactive protein. No major adverse cardiovascular events were observed throughout the study.

Prevalence, Pathophysiology, and Management of Androgen Deficiency in Men with Metabolic Syndrome, Type 2 Diabetes Mellitus, or Both

The prevalence of type 2 diabetes mellitus (T2DM) and metabolic syndrome (MetS) has increased in the United States over the past 40 years. These conditions, long linked with many cardiovascular complications, have recently been linked with androgen or testosterone deficiency in men. Several pathophysiologic hypotheses exist regarding this association, with the most widely reported a relationship to obesity and insulin resistance. Several randomized trials have confirmed that when testosterone replacement therapy is given to patients with T2DM, MetS, or both, metabolic parameters such as waist circumference, hemoglobin A1c , and systolic blood pressure are significantly reduced by up to 11 cm, 1.9%, and 23 mm Hg, respectively. This has not, however, resulted in improved cardiovascular outcomes, as evidenced in studies that found increased rates of cardiovascular events following testosterone replacement therapy. In this review, we summarize the relevant literature regarding the pathophysiology and management of androgen deficiency in men with T2DM, MetS, or both.

Diagnosing hypogonadism and treating decisions in different parts of the world: shifts in patterns between 2006 and 2015

AIM

Variations in diagnosing and treating testosterone (T) deficiency between different regions of the world were analyzed in 2006, and repeated in 2010. At present, the changes since 2006 were analyzed.

METHODS

About 731 physicians were interviewed in Europe, South Africa, Central and South America regarding factors determining: (1) prescription of T or withholding T, (2) factors in the long-term use of T and the role of T formulations therein, (3) awareness of the wider spectrum of action of T (cardiometabolic disease) (4) reimbursement of T and its impact on (continued) use and (5) best strategies for information on T for physicians.

RESULTS

Total T was a key factor in identifying hypogonadism, but for >80% of physicians, clinical symptoms were weighed during diagnosis. Once diagnosed, >85% received T treatment, but the treatment compliance was problematic. Of these patients, 36% decided not to start or continue the treatment.

CONCLUSION

More hypogonadal men are treated than before, but ∼20% goes unidentified. Physicians have a greater awareness that T deficiency can be an element in cardiovascular and metabolic disease, but more education of physicians on diagnosis and treatment of hypogonadism are needed. Problems with reimbursement of T are barriers in the prescription of T and its use by patients.

Insulin Resistance and Inflammation in Hypogonadotropic Hypogonadism and Their Reduction After Testosterone Replacement in Men With Type 2 Diabetes

OBJECTIVE

One-third of men with type 2 diabetes have hypogonadotropic hypogonadism (HH). We conducted a randomized placebo-controlled trial to evaluate the effect of testosterone replacement on insulin resistance in men with type 2 diabetes and HH.

RESEARCH DESIGN AND METHODS

A total of 94 men with type 2 diabetes were recruited into the study; 50 men were eugonadal, while 44 men had HH. Insulin sensitivity was calculated from the glucose infusion rate (GIR) during hyperinsulinemic-euglycemic clamp. Lean body mass and fat mass were measured by DEXA and MRI. Subcutaneous fat samples were taken to assess insulin signaling genes. Men with HH were randomized to receive intramuscular testosterone (250 mg) or placebo (1 mL saline) every 2 weeks for 24 weeks.

RESULTS

Men with HH had higher subcutaneous and visceral fat mass than eugonadal men. GIR was 36% lower in men with HH. GIR increased by 32% after 24 weeks of testosterone therapy but did not change after placebo (P = 0.03 for comparison). There was a decrease in subcutaneous fat mass (-3.3 kg) and increase in lean mass (3.4 kg) after testosterone treatment (P < 0.01) compared with placebo. Visceral and hepatic fat did not change. The expression of insulin signaling genes (IR-β, IRS-1, AKT-2, and GLUT4) in adipose tissue was significantly lower in men with HH and was upregulated after testosterone treatment. Testosterone treatment also caused a significant fall in circulating concentrations of free fatty acids, C-reactive protein, interleukin-1β, tumor necrosis factor-α, and leptin (P < 0.05 for all).

CONCLUSIONS

Testosterone treatment in men with type 2 diabetes and HH increases insulin sensitivity, increases lean mass, and decreases subcutaneous fat.

The Relationships between Anabolic Hormones and Body Composition in Middle-Aged and Elderly Men with Prediabetes: A Cross-Sectional Study

The influence of anabolic hormones and body composition in men with prediabetes (PD) is unknown. In a cross-sectional study we investigated the relationships between total testosterone (TT), calculated free testosterone (cFT), dehydroepiandrosterone sulfate (DHEAS), and insulin-like growth factor 1 (IGF-1) and body composition assessed using dual-energy X-ray absorptiometry (DXA) method in 84 patients with PD (40-80 years) and 56 men in control group. Patients with PD had lower TT, cFT, and DHEAS levels but similar IGF-1 levels in both groups. Patients with PD presented the higher total and abdominal fat as well as the lower total and abdominal lean than control (p < 0.02, p < 0.01, p < 0.05, and p < 0.02, resp.). We observed negative relationship between TT and total fat (p = 0.014) and positive with abdominal lean mass (p = 0.034), while cFT was negatively associated with abdominal (p = 0.02), trunk (p = 0.024), and leg fat (p = 0.037) and positively associated with total (p = 0.022) and trunk lean (p = 0.024). DHEAS were negatively associated with total fat (p = 0.045), and IGF-1 were positively associated with abdominal (p = 0.003) and leg lean (p = 0.015). In conclusion, the lowered anabolic hormones are involved in body composition rearrangement in men with PD. Further studies are needed to establish whether the androgen replacement therapy would be beneficial in men with PD.

An update on the role of testosterone replacement therapy in the management of hypogonadism

While US testosterone prescriptions have tripled in the last decade with lower trends in Europe, debate continues over the risks, benefits and appropriate use of testosterone replacement therapy (TRT). Some authors blame advertising and the availability of more convenient formulations whilst other have pointed out that the routine testing of men with erectile dysfunction (a significant marker of cardiovascular risk) and those with diabetes would inevitably increase the diagnosis of hypogonadism and lead to an increase in totally appropriate prescribing. They commented that this was merely an appropriate correction of previous underdiagnosis and undertreatment by adherence to evidence-based guidelines. Urologists and primary care physicians are the most frequent initiators of TRT, usually for erectile dysfunction. Benefits are clearly established for sexual function, increase in lean muscle mass and strength, mood and cognitive function, with possible reduction in frailty and osteoporosis. There remains no evidence that TRT is associated with increased risk of prostate cancer or symptomatic benign prostatic hyperplasia, yet the decision to initiate and continue therapy is often decided by urologists. The cardiovascular issues associated with TRT have been clarified by recent studies showing clearly that therapy associated with clear rise in testosterone levels are associated with reduced mortality. Studies reporting to show increased risk have been subject to flawed designs with inadequate baseline diagnosis and follow-up testing. Effectively they have compared nontreated patients with undertreated or on-compliant subjects involving a range of different therapy regimens. Recent evidence suggests long acting injections may be associated with decreased cardiovascular risk but the transdermal route may be associated with potentially relatively greater risk because of conversion to dihydrotestosterone by the effect of 5α reductase in skin. The multiple effects of TRT may add up to a considerable benefit to the patient that might be underestimated by the physician primarily concerned with his own specialty. This paper will attempt to identify who should be treated, and how they should be treated safely to achieve best outcomes, based on a comprehensive MEDLINE and EMBASE and Cochrane searches on hypogonadism, TRT and cardiovascular safety from May 2005 to May 2015. This revealed 1714 papers with 52 clinical trials and 32 placebo-controlled randomized, controlled trials.

Testosterone and metabolic syndrome

Controversies surround the usefulness of identifying patients with the metabolic syndrome (MetS). Many of the components are accepted risk factors for cardiovascular disease (CVD). Although the MetS as defined includes many men with insulin resistance, insulin resistance is not universal. The low total testosterone (TT) and sex hormone binding globulin (SHBG) levels in these men are best explained by the hyperinsulinism and increased inflammatory cytokines that accompany obesity and increased waist circumference. It is informative that low SHBG levels predict future development of the MetS. Evidence is strong relating low TT levels to CVD in men with and without the MetS; however, the relationship may not be causal. The recommendations of the International Diabetes Federation for managing the MetS include cardiovascular risk assessment, lifestyle changes in diet, exercise, weight reduction and treatment of individual components of the MetS. Unfortunately, it is uncommon to see patients with the MetS lose and maintain a 10% weight loss. Recent reports showing testosterone treatment induced dramatic changes in weight, waist circumference, insulin sensitivity, hemoglobin A1c levels and improvements in each of the components of the MetS are intriguing. While some observational studies have reported that testosterone replacement therapy increases cardiovascular events, the Food and Drug Administration in the United States has reviewed these reports and found them to be seriously flawed. Large, randomized, placebo-controlled trials are needed to provide more definitive data regarding the efficacy and safety of this treatment in middle and older men with the MetS and low TT levels.

Horizons in the Pharmacotherapy of Obesity

Obesity drugs have had a chequered history. In the recent past, only the low efficacy, pancreatic lipase inhibitor orlistat was available worldwide and it was little used. The 5HT2C agonist, lorcaserin, and two combinations of old drugs have been approved in the United States but not in Europe. The diabetes drug liraglutide has been approved in both the US and Europe and seems likely to be most widely accepted. In view of regulators' caution in approving obesity drugs, some (like beloranib) may initially be progressed for niche obesity markets. New drug targets have been identified in brown adipose tissue with the aim of not only activating thermogenesis but also increasing the capacity for thermogenesis in this tissue. Attempts are being made to match the efficacy of bariatric surgery by mimicking multiple gut hormones. Unapproved pharmacotherapies are tempting for some patients. Others remain optimistic about more conventional routes to pharmacotherapy.

Effects of testosterone treatment on glucose metabolism and symptoms in men with type 2 diabetes and the metabolic syndrome: a systematic review and meta-analysis of randomized controlled clinical trials

CONTEXT

The effects of testosterone treatment on glucose metabolism and other outcomes in men with type 2 diabetes (T2D) and/or the metabolic syndrome are controversial.

OBJECTIVE

To perform a systematic review and meta-analysis of placebo-controlled double-blind randomized controlled clinical trials (RCT) of testosterone treatment in men with T2D and/or the metabolic syndrome.

DATA SOURCES

A systematic search of RCTs was conducted using Medline, Embase and the Cochrane Register of controlled trials from inception to July 2014 followed by a manual review of the literature.

STUDY SELECTION

Eligible studies were published placebo-controlled double-blind RCTs published in English.

DATA EXTRACTION

Two reviewers independently selected studies, determined study quality and extracted outcome and descriptive data.

DATA SYNTHESIS

Of the 112 identified studies, seven RCTs including 833 men were eligible for the meta-analysis. In studies using a simple linear equation to calculate the homeostatic model assessment of insulin resistance (HOMA1), testosterone treatment modestly improved insulin resistance, compared to placebo, pooled mean difference (MD) -1·58 [-2·25, -0·91], P < 0·001. The treatment effect was nonsignificant for RCTs using a more stringent computer-based equation (HOMA2), MD -0·19 [-0·86, 0·49], P = 0·58). Testosterone treatment did not improve glycaemic (HbA1c) control, MD -0·15 [-0·39, 0·10], P = 0·25, or constitutional symptoms, Aging Male Symptom score, MD -2·49 [-5·81, 0·83], P = 0·14).

CONCLUSIONS

This meta-analysis does not support the routine use of testosterone treatment in men with T2D and/or the metabolic syndrome without classical hypogonadism. Additional studies are needed to determine whether hormonal interventions are warranted in selected men with T2D and/or the metabolic syndrome.

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 .

Effects of long-term treatment with testosterone on weight and waist size in 411 hypogonadal men with obesity classes I-III: observational data from two registry studies

BACKGROUND/OBJECTIVES

Long-term testosterone replacement therapy (TRT) up to 5 years has been shown to produce progressive and sustainable weight loss (WL) in hypogonadal men. This study investigated effects of long-term TRT up to 8 years in hypogonadal men with different obesity classes.

SUBJECTS/METHODS

From two independent observational registries we identified a total of 411 obese, hypogonadal men receiving TRT in urological clinics. The effects of TRT on anthropometric as well as metabolic parameters were studied for a maximum duration of 8 years, mean follow-up: 6 years. All men received long-acting injections of testosterone undecanoate in 3-monthly intervals.

RESULTS

In all three classes of obesity, T therapy produced significant WL, decrease in waist circumference (WC) and body mass index (BMI). In patients with class I obesity, mean weight decreased from 102.6±6.4 to 84.1±4.9 kg, change from baseline: -17.4±0.5 kg and -16.8±0.4%. WC in this group of patients decreased from 106.8±7.4 to 95.1±5.3 cm, change from baseline: -10.6±0.3 cm. BMI decreased from 32.69±1.4 to 27.07±1.57, change from baseline: -5.52±0.15 kg m(-2). In patients with class II obesity, weight decreased from 116.8±6.9 to 91.3±6.3 kg, change from baseline: -25.3±0.5 kg and -21.5±0.4%. WC decreased from 113.5±7.5 to 100.0±5.4 cm, change from baseline: -13.9±0.4 cm. BMI decreased from 37.32±1.45 to 29.49±1.71, change from baseline: -8.15±0.17 kg m(-2). In patients with class III obesity, weight decreased from 129.0±5.6 to 98.9±4.8 kg, change from baseline: -30.5±0.7 kg and -23.6±0.5%. WC decreased from 118.5±5.6 to 103.8±4.9 cm, change from baseline: -14.3±0.4 cm. BMI decreased from 41.93±1.48 to 32.46±1.59, change from baseline -9.96±0.29 kg m(-2).

CONCLUSIONS

Testosterone therapy appears to be an effective approach to achieve sustained WL in obese hypogonadal men irrespective of severity of obesity. Based on these findings we suggest that T therapy offers safe and effective treatment strategy of obesity in hypogonadal men.

Testosterone and obesity

Testosterone is a key hormone in the pathology of metabolic diseases such as obesity. Low testosterone levels are associated with increased fat mass (particularly central adiposity) and reduced lean mass in males. These morphological features are linked to metabolic dysfunction, and testosterone deficiency is associated with energy imbalance, impaired glucose control, reduced insulin sensitivity and dyslipidaemia. A bidirectional relationship between testosterone and obesity underpins this association indicated by the hypogonadal-obesity cycle and evidence weight loss can lead to increased testosterone levels. Androgenic effects on enzymatic pathways of fatty acid metabolism, glucose control and energy utilization are apparent and often tissue specific with differential effects noted in different regional fat depots, muscle and liver to potentially explain the mechanisms of testosterone action. Testosterone replacement therapy demonstrates beneficial effects on measures of obesity that are partially explained by both direct metabolic actions on adipose and muscle and also potentially by increasing motivation, vigour and energy allowing obese individuals to engage in more active lifestyles. The degree of these beneficial effects may be dependent on the treatment modality with longer term administration often achieving greater improvements. Testosterone replacement may therefore potentially be an effective adjunctive treatment for weight management in obese men with concomitant hypogonadism.

Aspects of androgen replacement therapy for the treatment of hypogonadism in men with diabetes and metabolic syndrome

The article presents the results of studies of efficacy and safety of androgen therapy for hypogonadism, metabolic syndrome and type 2diabetes mellitus in men. In the study was used testosterone undecanoate therapy which causes reduction of obesity, a decrease in theseverity of the other components of the metabolic syndrome, improving glycemic profile without significant side effects. Nevertheless,this therapy requires monitoring and management for risk factors.

Association of sex hormones with carotid artery distensibility in men and postmenopausal women: multi-ethnic study of atherosclerosis

The decline in carotid distensibility with age is steeper in women than in men, however, the correlates of this sex difference are not known. We examined the association of bioavailable testosterone, estradiol, dehydroepiandrosterone, and sex hormone-binding globulin, in 2783 postmenopausal women and 2987 men aged 45 to 84 years at the Multi-Ethnic Study of Atherosclerosis baseline examination. Carotid artery lumen diameters by ultrasound and brachial artery blood pressures were measured at systole and diastole. Regression models to determine the association of carotid distensibility coefficient and lumen diameter with sex-specific quartiles of sex hormones were adjusted for age, race, height, weight, diabetes mellitus, current smoking, antihypertensive medication use, total and high-density lipoprotein cholesterol levels, and hormone replacement therapy in women. A higher DC indicates a more distensible vessel. In women, higher dehydroepiandrosterone (P=0.008) and lower sex hormone-binding globulin (P=0.039) were associated with lower distensibility; higher dehydroepiandrosterone and lower estradiol were associated with smaller carotid diameters. In men, higher Bio-T (P=0.009) and lower estradiol (P=0.007) were associated with greater distensibility and also with smaller diameters (P=0.012 and 0.002, respectively). An androgenic internal milieu is associated with lesser carotid distensibility and diameter remodeling in women, but the opposite is true for men. Higher levels of estradiol are associated with smaller carotid diameters in both the sexes. Future longitudinal and experimental studies are needed to reveal the mechanism and clinical consequences of these associations.

Recommendations on the diagnosis, treatment and monitoring of hypogonadism in men

Hypogonadism or Testosterone Deficiency (TD) in adult men as defined by low levels of serum testosterone accompanied by characteristic symptoms and/or signs as detailed further on can be found in long-recognized clinical entities such as Klinefelter syndrome, Kallmann syndrome, pituitary or testicular disorders, as well as in men with idiopathic, metabolic or iatrogenic conditions that result in testosterone deficiency. These recommendations do not encompass the full range of pathologies leading to hypogonadism (testosterone deficiency), but instead focus on the clinical spectrum of hypogonadism related to metabolic and idiopathic disorders that contribute to the majority of cases that occur in adult men.

Late-onset hypogonadism among old and middle-aged males with prediabetes in Polish population

OBJECTIVES

Around 40% of diabetic men have lowered testosterone and symptoms of hypogonadism but the prevalence of hypogonadism among prediabetic men is unknown. The aim of this study was to investigate the prevalence of late-onset hypogonadism (LOH) in population of Polish men with prediabetes.

METHODS

This study was performed in 196 prediabetic men and in 184 normoglycemic, control group. Prediabetes was defined as impaired fasting glucose, impaired glucose tolerance and/or HbA1c 5.7-6.4%. LOH was defined as low libido, diminished frequency of morning erections and erectile dysfunctions in men with total testosterone <12 nmol/l.

RESULTS

Total testosterone (TT) level in prediabetes group was 11.78 ± 1.76 and 16.37 ± 1.6 nmol/l in control group (p < 0.001). LOH was diagnosed in 30% prediabetic men and in 13.6% control men. There were negative relationships between calculated free testosterone (cFT) and HbA1c (r = -0.3856; p < 0.005). In prediabetic group, TT and cFT levels were lower in patients with impaired glucose tolerance than impaired fasting glucose (p < 0.05 and p < 0.02, respectively). We showed inverse relationships between IIEF-5 score and cFT (r = -0.414, p < 0.005) and between IIEF-5 and HbA1c (r = -0.395, p < 0.002).

CONCLUSIONS

In population of Polish men with prediabetes we observed high prevalence of LOH. Routine testosterone screening should be performed in all prediabetic men.

Testosterone therapy and cardiovascular risk: advances and controversies

Two recent studies raised new concerns regarding cardiovascular (CV) risks with testosterone (T) therapy. This article reviews those studies as well as the extensive literature on T and CV risks. A MEDLINE search was performed for the years 1940 to August 2014 using the following key words: testosterone, androgens, human, male, cardiovascular, stroke, cerebrovascular accident, myocardial infarction, heart attack, death, and mortality. The weight and direction of evidence was evaluated and level of evidence (LOE) assigned. Only 4 articles were identified that suggested increased CV risks with T prescriptions: 2 retrospective analyses with serious methodological limitations, 1 placebo-controlled trial with few major adverse cardiac events, and 1 meta-analysis that included questionable studies and events. In contrast, several dozen studies have reported a beneficial effect of normal T levels on CV risks and mortality. Mortality and incident coronary artery disease are inversely associated with serum T concentrations (LOE IIa), as is severity of coronary artery disease (LOE IIa). Testosterone therapy is associated with reduced obesity, fat mass, and waist circumference (LOE Ib) and also improves glycemic control (LOE IIa). Mortality was reduced with T therapy in 2 retrospective studies. Several RCTs in men with coronary artery disease or heart failure reported improved function in men who received T compared with placebo. The largest meta-analysis to date revealed no increase in CV risks in men who received T and reduced CV risk among those with metabolic disease. In summary, there is no convincing evidence of increased CV risks with T therapy. On the contrary, there appears to be a strong beneficial relationship between normal T and CV health that has not yet been widely appreciated.

Effects of long-term testosterone replacement therapy, with a temporary intermission, on glycemic control of nine hypogonadal men with type 1 diabetes mellitus - a series of case reports

Type 2 diabetes mellitus (T2DM) is often associated with obesity and subnormal serum testosterone (T) levels. Until 5 years ago there was no indication that men with type 1 diabetes mellitus (T1DM) had subnormal serum T. But recent studies indicate that about 10% of men with T1DM suffer from hypogonadism, as a rule aged men and men with obesity. While hypogonadal men with T2DM benefit from normalization of their serum T, this has not been investigated in men with T1DM. Nine men with T1DM, erectile dysfunction and hypogonadism (total testosterone ≤ 12 nmol/L) received testosterone replacement therapy (TRT). In seven men TRT was intermitted: one man with prostate malignancy and six men because of problems of reimbursement. Incidentally, this provided an opportunity to monitor the effects of withdrawal and of the reinstatement of TRT. In all men, glycemic control (serum glucose and HbA1c), weight, waist circumference, lipid profiles and erectile function improved upon TRT. The seven men whose TRT was intermitted showed a deterioration which improved again upon reinstatement of TRT. The data suggest that aging and obese men with T1DM might have subnormal T levels and that their glycemic control, lipid profiles and erectile function might benefit from TRT.

Testosterone Replacement and Cardiovascular Safety: No Straight and Narrow!

The past decade has seen a tremendous increase in the number of men treated for hypogonadism with the expectation of symptomatic benefit. However, the long-term cardiovascular safety of testosterone replacement remains unknown because retrospective studies of testosterone replacement have been inconsistent, and definitive, prospective, randomized studies are lacking. The purpose of this review is to critically appraise the studies on testosterone replacement and cardiovascular outcomes.

Hormonal determinants of erectile dysfunction and lower urinary tract symptoms in middle-aged and elderly men with prediabetes

OBJECTIVES

Erectile dysfunction (ED) and lower urinary tract symptoms (LUTS) are common in diabetic men. The aim of this study was to investigate hormonal determinants, the prevalence and severity of ED and LUTS in middle-aged and elderly men with prediabetes (PD).

METHODS

We investigated 176 men with PD and 184 healthy peers. PD was defined according American Diabetes Association. ED according IIEF scale and LUTS according IPSS scale were assessed. Total testosterone (TT), calculated free testosterone (cFT), dehydroepiandrosterone sulfate (DHEAS) and insulin-like growth factor 1 (IGF-1) were measured.

RESULTS

The prevalence of ED in patients with PD was higher than in control group (30 versus 24%) as well as the prevalence and severity of ED and LUTS in elderly (60-80 years) and middle-aged (40-59 years) men with PD was higher than in healthy peers. In middle-aged pre-diabetic men, the more severe LUTS symptoms were associated with low TT and DHEAS, while in elderly men with low cFT and DHEAS. The higher prevalence of ED in middle-aged men with PD was associated with cFT and DHEAS, while in elderly pre-diabetic men with TT and IGF-1.

CONCLUSIONS

The prevalence and severity of LUTS and ED symptoms were higher in pre-diabetic men than in healthy peers. Hormonal determinants of these symptoms are different in middle-aged and elderly patients with PD.

Testosterone and weight loss: the evidence

PURPOSE OF REVIEW

The purpose of this article is to examine the contemporary data linking testosterone therapy in overweight and obese men with testosterone deficiency to increased lean body mass, decreased fat mass, improvement in overall body composition and sustained weight loss. This is of paramount importance because testosterone therapy in obese men with testosterone deficiency represents a novel and a timely therapeutic strategy for managing obesity in men with testosterone deficiency.

RECENT FINDINGS

Long-term testosterone therapy in men with testosterone deficiency produces significant and sustained weight loss, marked reduction in waist circumference and BMI and improvement in body composition. Further, testosterone therapy ameliorates components of the metabolic syndrome. The aforementioned improvements are attributed to improved mitochondrial function, increased energy utilization, increased motivation and vigor resulting in improved cardio-metabolic function and enhanced physical activity.

SUMMARY

The implication of testosterone therapy in management of obesity in men with testosterone deficiency is of paramount clinical significance, as it produces sustained weight loss without recidivism. On the contrary, alternative therapeutic approaches other than bariatric surgery failed to produce significant and sustained outcome and exhibit a high rate of recidivism. These findings represent strong foundations for testosterone therapy in obese men with testosterone deficiency and should spur clinical research for better understanding of usefulness of testosterone therapy in treatment of underlying pathophysiological conditions of obesity.