Abrupt decrease in serum testosterone levels after an oral glucose load in men: implications for screening for hypogonadism

Standardising the biochemical confirmation of adult male hypogonadism: A joint position statement by the Society for Endocrinology and Association of Clinical Biochemistry and Laboratory Medicine

BACKGROUND

Inter-assay variation between different immunoassays and different mass spectrometry methods hampers the biochemical confirmation of male hypogonadism. Furthermore, some laboratories utilise assay manufacturer reference ranges that do not necessarily mirror assay performance characteristics, with the lower limit of normality ranging from 4.9 nmol/L to 11 nmol/L. The quality of the normative data underlying commercial immunoassay reference ranges is uncertain.

DESIGN

A working group reviewed published evidence and agreed upon standardised reporting guidance to augment total testosterone reports.

RESULTS

Evidence-based guidance on appropriate blood sampling, clinical action limits, and other major factors likely to affect the interpretation of results are provided.

CONCLUSIONS

This article aims to improve the quality of the interpretation of testosterone results by non-specialist clinicians. It also discusses approaches for assay harmonisation which have been successful in some but not all healthcare systems.

Male hypogonadism: pathogenesis, diagnosis, and management

Organic male hypogonadism due to irreversible hypothalamic-pituitary-testicular (HPT) pathology is easily diagnosed and treated with testosterone-replacement therapy. However, controversy surrounds the global practice of prescribing testosterone to symptomatic men with low testosterone and non-gonadal factors reducing health status, such as obesity, type 2 diabetes, and ageing (ie, functional hypogonadism), but without identifiable HPT axis pathology. Health optimisation remains the gold-standard management strategy. Nevertheless, in the last decade large clinical trials and an individual patient data meta-analysis of smaller clinical trials confirmed that testosterone therapy induces modest, yet statistically significant, improvements in sexual function without increasing short-term to medium-term cardiovascular or prostate cancer risks in men with functional hypogonadism. Although testosterone improves bone mineral density and insulin sensitivity in these men, trials from the last decade suggest insufficient evidence to determine the safety and effectiveness of use of this hormone for the prevention of fractures or type 2 diabetes. This Review discusses the pathogenesis and diagnosis of male hypogonadism and appraises the evidence underpinning the management of this condition.

Salivary testosterone changes during oral glucose tolerance tests in overweight and obese men - Postprandial or circadian variation?

BACKGROUND

Serum total testosterone (T) decreases postprandially. Postprandial salivary testosterone (SalT) responses, however, have not been studied. We report on the effect of glucose ingestion on fasting SalT concentrations.

OBJECTIVE

To investigate the effect of oral glucose ingestion on fasting SalT.

METHODS

Salivary and blood samples were collected between 09.00 and 09.30 and 2 hours after a 75g oral glucose load in 32 men with mean (standard deviation) age of 52 (5.7) years and body mass index of 32.6 (5.56) kg/m2. Free T and bioavailable testosterone (BAT) were calculated using the Vermeulen equation.

RESULTS

Two hours following oral glucose, there was a decrease in fasting mean (standard deviation) SalT [178.2 (56.6) versus 146.0 (42.2) pmol/L; P = .0003], serum cortisol [332 (105.0) versus 239 (75.3) nmol/L; P = <0.0001], prolactin [193 (75.0) versus 127 (55.9) mIU/L; P = <0.0001] and TSH [1.60 (0.801) versus 1.16 (0.584) mIU/L; P = <0.0001]. Plasma glucose increased [6.2 (0.72) versus 8.1 (3.71) mmol/L; P = .0029]. Serum total T, SHBG, albumin, Free T, BAT, gonadotrophins and FT4 remained unchanged.

CONCLUSIONS

SalT decreased postprandially. A concomitant decrease in serum cortisol, prolactin and TSH reflecting diurnal variation offers an alternative explanation for the decrease in SalT independent of food consumption. Further studies are required to determine whether morning temporal changes in SalT are related to food consumption or circadian rhythm or both.

Glucose ingestion does not lower testosterone concentrations in men on testosterone therapy

Oral calorie intake causes an acute and transient decline in serum testosterone concentrations. It is not known whether this decline occurs in men on testosterone therapy. In this study, we evaluated the change in testosterone concentrations following oral glucose ingestion in hypogonadal men before and after treatment with testosterone therapy. This is a secondary analysis of samples previously collected from a study of hypogonadal men with type 2 diabetes who received testosterone therapy. Study participants (n = 14) ingested 75 grams of oral glucose, and blood samples were collected over 2 h. The test was repeated after 23 weeks of intramuscular testosterone therapy. The mean age and body mass index of study volunteers were 53 ± 8 years and 38 ± 7 kg/m2, respectively. Following glucose intake, testosterone concentrations fell significantly prior to testosterone therapy (week 0, p = 0.04). The nadir of testosterone concentration was at 1 h, followed by recovery to baseline by 2 h. In contrast, there was no change in testosterone concentrations at week 23. The change in serum testosterone concentrations at 60 min was significantly more at week 0 than week 23 (-11 ± 10% vs 0 ± 16%, p = 0.05). We conclude that oral glucose intake has no impact on testosterone concentrations in men on testosterone therapy. Endocrinology societies should consider clarifying in their recommendations that fasting testosterone concentrations are required for the diagnosis of hypogonadism, but not for monitoring testosterone therapy.

Quantifying the variability in the assessment of reproductive hormone levels

OBJECTIVE

To quantify how representative a single measure of reproductive hormone level is of the daily hormonal profile using data from detailed hormonal sampling in the saline placebo-treated arm conducted over several hours.

DESIGN

Retrospective analysis of data from previous interventional research studies evaluating reproductive hormones.

SETTING

Clinical Research Facility at a tertiary reproductive endocrinology centre at Imperial College Hospital NHS Foundation Trust.

PATIENTS

Overall, 266 individuals, including healthy men and women (n = 142) and those with reproductive disorders and states (n = 124 [11 with functional hypothalamic amenorrhoea, 6 with polycystic ovary syndrome, 62 women and 32 men with hypoactive sexual desire disorder, and 13 postmenopausal women]), were included in the analysis.

INTERVENTIONS

Data from 266 individuals who had undergone detailed hormonal sampling in the saline placebo-treated arms of previous research studies was used to quantify the variability in reproductive hormones because of pulsatile secretion, diurnal variation, and feeding using coefficient of variation (CV) and entropy.

MAIN OUTCOME MEASURES

The ability of a single measure of reproductive hormone level to quantify the variability in reproductive hormone levels because of pulsatile secretion, diurnal variation, and nutrient intake.

RESULTS

The initial morning value of reproductive hormone levels was typically higher than the mean value throughout the day (percentage decrease from initial morning measure to daily mean: luteinizing hormone level 18.4%, follicle-stimulating hormone level 9.7%, testosterone level 9.2%, and estradiol level 2.1%). Luteinizing hormone level was the most variable (CV 28%), followed by sex-steroid hormone levels (testosterone level 12% and estradiol level 13%), whereas follicle-stimulating hormone level was the least variable reproductive hormone (CV 8%). In healthy men, testosterone levels fell between 9:00 am and 5:00 pm by 14.9% (95% confidence interval 4.2, 25.5%), although morning levels correlated with (and could be predicted from) late afternoon levels in the same individual (r2 = 0.53, P<.0001). Testosterone levels were reduced more after a mixed meal (by 34.3%) than during ad libitum feeding (9.5%), after an oral glucose load (6.0%), or an intravenous glucose load (7.4%).

CONCLUSION

Quantification of the variability of a single measure of reproductive hormone levels informs the reliability of reproductive hormone assessment.

Sex steroids and androgen biomarkers in the healthy man study: within-person variability and impact of fasting

OBJECTIVE

Serum testosterone measurements in clinical practice mostly utilize "direct" (non-extraction) immunoassays which have method-specific bias due to steroid cross-reactivity and nonspecific matrix artifacts. Although more accurate, sensitive, and specific liquid chromatography-mass spectrometry (LCMS) dominates in clinical research, the within-person variability of serum testosterone in healthy men using LCMS measurement is not reported.

DESIGN

Longitudinal multi-sampling observational study of men in excellent health over 3 months.

METHODS

Elite healthy men (n = 325) over 40 years of age in excellent, asymptomatic health provided 9 blood samples over 3 months with serum testosterone, dihydrotestosterone (DHT), estradiol (E2), and estrone (E1) measured by validated LCMS with conventional biochemical and anthropometric variables.

RESULTS

Quantitative estimates of within-person variability within day and between day, week, month, and quarter were stable other than an increase due to fasting. The androgen biomarkers most sensitive to age and testosterone among widely used biochemical and anthropometric variables in middle-aged and older men were identified.

CONCLUSIONS

This study provides estimates of variability in serum testosterone and the best androgen biomarkers that may prove useful for future studies of androgen action in male ageing.

Adult Male Hypogonadism: A Laboratory Medicine Perspective on Its Diagnosis and Management

Testosterone (T), the principal androgen secreted by the testes, plays an essential role in male health. Male hypogonadism is diagnosed based on a combination of associated clinical signs and symptoms and laboratory confirmation of low circulating T levels. In this review, we have highlighted factors, both biological and analytical, that introduce variation into the measurement of serum T concentrations in men; these need to be considered when requesting T levels and interpreting results. There is an ongoing need for analytical standardisation of T assays and harmonisation of pre- and post-analytical laboratory practices, particularly in relation to the laboratory reference intervals provided to clinicians. Further, there is a need to share with service users the most up-to-date and evidence-based action thresholds for serum T as recommended in the literature. Estimation of free testosterone may be helpful. Causes of secondary hypogonadism should be considered. A comprehensive approach is required in the management of male hypogonadism, including lifestyle modification as well as medication where appropriate. The goal of treatment is the resolution of symptoms as well as the optimisation of metabolic, cardiovascular, and bone health. The advice of an endocrinologist should be sought when there is doubt about the cause and appropriate management of the hypogonadism.

Factors predicting normalization of reproductive hormones after cessation of anabolic-androgenic steroids in men: a single center retrospective study

OBJECTIVE

Symptomatic hypogonadism discourages men from stopping anabolic-androgenic steroids (AAS). Some men illicitly take drugs temporarily stimulating endogenous testosterone following AAS cessation (post-cycle therapy; PCT) to lessen hypogonadal symptoms. We investigated whether prior PCT use was associated with the normalization of reproductive hormones following AAS cessation.

METHODS

Retrospective analysis of 641 men attending a clinic between 2015-2022 for a single, nonfasting, random blood test <36 months following AAS cessation, with or without PCT. Normalized reproductive hormones (ie, a combination of reference range serum luteinizing hormone, follicle-stimulating hormone, and total testosterone levels) were the surrogate marker of biochemical recovery.

RESULTS

Normalization of reproductive hormones was achieved in 48.2% of men. PCT use was associated with faster biochemical recovery (13.0 (IQR8.0-19.0) weeks, PCT; 26.0 (IQR10.5-52) weeks, no-PCT; P < .001). Odds of biochemical recovery during multivariable analysis were: (1) higher with PCT (OR3.80) vs no-PCT (P = .001), in men stopping AAS ≤3 months previously; (2) reduced when 2 (OR0.55), 3 (OR0.46), or 4 (OR0.25) AAS were administered vs 1 drug (P = .009); (3) lower with AAS >6 vs ≤3 months previously (OR0.34, P = .01); (4) higher with last reported AAS >3 months (OR 5.68) vs ≤3 months (P = .001). PCT use was not associated with biochemical recovery in men stopping AAS >3 months previously.

CONCLUSION

Without evidence-based withdrawal protocols, men commonly try avoiding post-AAS hypogonadism with PCT, which is illicit, ill-defined, and not recommended. Only half of men had complete biochemical testicular recovery after stopping AAS. The surprising association of self-reported PCT use with short-term biochemical recovery from AAS-induced hypogonadism warrants further investigation.

Effects of the low-carb organic Mediterranean diet on testosterone levels and sperm DNA fragmentation

The causes of male infertility can vary. Lifestyles, environmental factors, stressful conditions, and socio-economic conditions are significant factors. Diet plays a crucial role in improving a man's reproductive capacity. The appropriate diet should be diverse and ensure the intake of all the necessary nutrients to enhance sperm quality. The Mediterranean diet, which includes high amounts of vegetables and fruits rich in detoxifying and antioxidant substances, as well as polyphenols, flavonoids, carotenoids, and microelements, especially when consumed with organic foods and a lower carbohydrate regimen, are the key aspects addressed in this study. The objective of this research was to modify the diets of 50 subfertile men by providing them with a specific nutritional plan. This plan included consuming 80% organic foods, introducing whole grains and low glycemic load options, eliminating refined carbohydrates, consuming green leafy vegetables and red fruits daily, reducing or eliminating dairy products, consuming primarily grass-fed meat and wild caught seafood, eliminating saturated fats in favor of healthy fats like olive oil, avocado, and nuts. After three months of adhering to the low-carb food plan, testosterone levels significantly increased, while sperm DNA fragmentation decreased in a subgroup of individuals who reduced their carbohydrate intake by 35%.

The British Society for Sexual Medicine Guidelines on Male Adult Testosterone Deficiency, with Statements for Practice

Testosterone deficiency (TD) is an increasingly common problem with significant health implications, but its diagnosis and management can be challenging. A multi-disciplinary panel from BSSM reviewed the available literature on TD and provide evidence-based statements for clinical practice. Evidence was derived from Medline, EMBASE and Cochrane searches on hypogonadism, testosterone therapy (T Therapy) and cardiovascular safety from May 2017 to September 2022. This revealed 1,714 articles, including 52 clinical trials and 32 placebo-controlled randomised controlled trials. A total of twenty-five statements are provided, relating to five key areas: screening, diagnosis, initiating T Therapy, benefits and risks of T Therapy, and follow-up. Seven statements are supported by level 1 evidence, eight by level 2, five by level 3, and five by level 4. Recent studies have demonstrated that low levels of testosterone in men are associated with increased risk of incident type 2 diabetes mellitus, worse outcomes in chronic kidney disease and COVID 19 infection with increased all-cause mortality, along with significant quality of life implications. These guidelines should help practitioners to effectively diagnose and manage primary and age-related TD.

Fasting Versus Non-Fasting Total Testosterone Levels in Women During the Childbearing Period

Background Total testosterone in men should be measured in the fasting state early in the morning with at least two samples according to guidelines. For women, no such a recommendation is available despite the importance of testosterone in this demographic. The aim of this study is to evaluate the effect of fasting versus non-fasting state on the total testosterone levels in women during the reproductive period. Methods This study was conducted at Faiha Specialized Diabetes, Endocrine and Metabolism Center in Basrah, (Southern Iraq) between January 2022 to November 2022. The total enrolled women were 109; their age was 18-45 years. The presentation was for different complaints; 56 presented for medical consultation with 45 apparently healthy women accompanying the patients as well as eight volunteering female doctors. Testosterone levels were measured by electrochemiluminescence immunoassays using the Roche Cobas e411 platform (Roche Holding, Basel, Switzerland). Two samples were collected from each woman; one was fasting and another was non-fasting the following day, and all samples were taken before 10 am. Results  For all of the participants, the mean ± SD fasting was significantly higher as compared to the non-fasting testosterone (27.39±18.8 ng/dL and 24.47±18.6 ng/dL respectively, p-value 0.01). The mean fasting testosterone level was also significantly higher in the apparently healthy group, (p-value 0.01). In women who presented with hirsutism, menstrual irregularities and or hair fall, no difference was seen in the testosterone levels between fasting and non-fasting states (p-value 0.4).  Conclusion In the apparently healthy women of childbearing age, serum testosterone levels were higher in the fasting versus the non-fasting states. In women who presented with complaints of hirsutism, menstrual irregularities, and or hair fall, the serum testosterone levels were not affected by the fasting states.

Diagnosis of hypogonadism in ageing men

To make the diagnosis of hypogonadism in an ageing man, in absence of rare organic cause often referred to as functional or late onset hypogonadism (LOH), he should present with a clinical syndrome suggestive of androgen deficiency and have consistently low serum testosterone (T) levels. This does not differ from the diagnosis of any other form of hypogonadism. Particular to LOH diagnostic are uncertainties surrounding this entity: signs and symptoms of androgen deficiency (including sexual symptoms) are nonspecific in older men; clinical significance of only moderately low T levels is uncertain; comorbidity plays a substantial role with potential for reversibility; the place of T therapy in these men is debatable. This context demands for a pragmatic, but appropriately conservative approach to diagnosis. Evaluation should be stepwise with clinical evaluation, if suggestive for androgen deficiency, followed by measurement of a fasting morning serum T, if unequivocally low to be confirmed in a separate morning sample by a second low T or, if initial T borderline low or in presence of factors known to affect SHBG, by a low calculated free T level. All other (free) T results make hypogonadism an unlikely cause of the patient's symptoms. In the absence of consensus cut-off levels for total and free T in the published clinical guidelines for diagnosis of hypogonadism, it seems appropriate in the context of LOH to use stringent criteria indicating a convincingly low serum T. The approach to the diagnosis of LOH is not fundamentally different from that of other forms of hypogonadism but should put extra weight on prioritizing the shunning of overdiagnosis above the risk of underdiagnosis.

Functional hypogonadism among patients with obesity, diabetes, and metabolic syndrome

Testosterone deficiency, defined as low total testosterone combined with physical, cognitive, and sexual signs and/or symptoms, is a common finding in adult men. Functional hypogonadism (FH) is defined as borderline low testosterone (T) secondary to aging and/or comorbid conditions such as diabetes, obesity, and/or metabolic syndrome. The relationship between FH and metabolic disorders is multifactorial and bidirectional, and associated with a disruption of the hypothalamic-pituitary-gonadal axis. Resolution of FH requires the correct diagnosis and treatment of the underlying condition(s) with lifestyle modifications considered first-line therapy. Normalization of T levels through dietary modifications such as caloric restriction and restructuring of macronutrients have recently been explored. Exercise and sleep quality have been associated with T levels, and patients should be encouraged to practice resistance training and sleep seven to nine hours per night. Supplementation with vitamin D and Trigonella foenum-graecum may also be considered when optimizing T levels. Ultimately, treatment of FH requires a multidisciplinary approach and personalized patient care.

Improving the accuracy of fatty liver index to reflect liver fat content with predictive regression modelling

Background

The fatty liver index (FLI) is frequently used as a non-invasive clinical marker for research, prognostic and diagnostic purposes. It is also used to stratify individuals with hepatic steatosis such as non-alcoholic fatty liver disease (NAFLD), and to detect the presence of type 2 diabetes or cardiovascular disease. The FLI is calculated using a combination of anthropometric and blood biochemical variables; however, it reportedly excludes 8.5-16.7% of individuals with NAFLD. Moreover, the FLI cannot quantitatively predict liver fat, which might otherwise render an improved diagnosis and assessment of fatty liver, particularly in longitudinal studies. We propose FLI+ using predictive regression modelling, an improved index reflecting liver fat content that integrates 12 routinely-measured variables, including the original FLI.

Methods and findings

We evaluated FLI+ on a dataset from the UK Biobank containing 28,796 individual estimates of proton density fat fraction derived from magnetic resonance imaging across normal to severe levels and interpolated to align with the original FLI range. The results obtained for FLI+ outperform the original FLI by delivering a lower mean absolute error by approximately 47%, a lower standard deviation by approximately 20%, and an increased adjusted R² statistic by approximately 49%, reflecting a more accurate representation of liver fat content.

Conclusions

Our proposed model predicting FLI+ has the potential to improve diagnosis and provide a more accurate stratification than FLI between absent, mild, moderate and severe levels of hepatic steatosis.

Accurate measurement of total and free testosterone levels for the diagnosis of androgen disorders

The circulating concentrations of total and free testosterone vary substantially in people over time due to biologic factors as well as due to measurement variation. Accurate measurement of total and free testosterone is essential for making the diagnosis of androgen disorders. Total testosterone should ideally be measured in a fasting state in the morning using a reliable assay, such as liquid chromatography tandem mass spectrometry, in a laboratory that is certified by an accuracy-based benchmark. Free testosterone levels should be measured in men in whom alterations in binding protein concentrations are suspected or in whom total testosterone levels are only slightly above or slightly below the lower limit of the normal male range for testosterone.

Nutrients and pheromones promote insulin release to inhibit courtship drive

Food and reproduction are the fundamental needs for all animals. However, the neural mechanisms that orchestrate nutrient intake and sexual behaviors are not well understood. Here, we find that sugar feeding immediately suppresses sexual drive of male Drosophila, a regulation mediated by insulin that acts on insulin receptors on the courtship-promoting P1 neurons. The same pathway was co-opted by anaphrodisiac pheromones to suppress sexual hyperactivity to suboptimal mates. Activated by repulsive pheromones, male-specific PPK23 neurons on the leg tarsus release crustacean cardioactive peptide (CCAP) that acts on CCAP receptor on the insulin-producing cells in the brain to trigger insulin release, which then inhibits P1 neurons. Our results reveal how male flies avoid promiscuity by balancing the weight between aphrodisiac and anaphrodisiac inputs from multiple peripheral sensory pathways and nutritional states. Such a regulation enables male animals to make an appropriate mating decision under fluctuating feeding conditions.

Accurate Measurement and Harmonized Reference Ranges for Total and Free Testosterone Levels

Diagnosing testosterone deficiency requires accurate and precise measurement of total testosterone levels by an accurate method, such as liquid chromatography-tandem mass spectrometry in a laboratory certified by an accuracy-based program (eg, Centers for Disease Control and Prevention's Hormone Standardization (HoST) Program), and, if needed, free testosterone level. Free testosterone level should ideally be measured by equilibrium dialysis method. Testosterone levels should be measured in 2 or more fasting samples obtained in the morning. Harmonized reference ranges for total testosterone can be applied to laboratories that certified by the HoST Program.

Diagnosis and Evaluation of Hypogonadism

A systematic approach to diagnose hypogonadism initially establishes the presence of symptoms/signs of testosterone deficiency, considers other potential causes of manifestations, and excludes conditions that transiently suppress testosterone. Hypogonadism is confirmed by measuring fasting serum total testosterone in the morning on at least 2 separate days, or free testosterone by equilibrium dialysis or calculated free testosterone in men with conditions that alter sex hormone-binding globulin or serum total testosterone near lower limit of normal. To guide management, further evaluation is performed to identify the specific cause of hypogonadism and whether it is potentially reversible or an irreversible pathologic disorder.

Testosterone, Diabetes Risk, and Diabetes Prevention in Men

Middle-aged and older men with lower testosterone concentrations are more likely to have or to develop metabolic syndrome and type 2 diabetes. Central adiposity is a risk factor for metabolic syndrome and diabetes and predisposes to lower testosterone concentrations. Conversely, testosterone treatment reduces fat mass and insulin resistance. In a randomized controlled trial of 1007 men with either impaired glucose tolerance or newly diagnosed type 2 diabetes, 2 years of testosterone treatment on a background of lifestyle intervention reduced the risk of type 2 diabetes by 40%; this demonstrates the potential utility for testosterone pharmacotherapy to prevent diabetes in men.

Recommendations on the diagnosis, treatment and monitoring of testosterone deficiency in men

The relative proportional increase of the elderly population within many countries will become one of the most significant social transformations of the twenty-first century and, for the first time in history, persons aged 65 or above outnumbered children under five years of age globally. One in four persons living in Europe and Northern America will be aged 65 or over. One of the goals of ISSAM is to raise awareness of the special health needs of older men. Since a significant number of aging men will eventually become testosterone deficient, the Hypogonadism panel of ISSAM updates its guidelines.

Optimizing the Diagnostic Accuracy and Treatment Decisions in Men with Testosterone Deficiency

OBJECTIVE

This narrative review offers a guideline-based approach to optimizing the diagnostic evaluation and treatment decision-making in men being evaluated for testosterone deficiency.

METHODS

A narrative review RESULTS: Testosterone deficiency is a clinical syndrome that results from the inability of the testes to produce normal amounts of testosterone, and is characterized by a constellation of symptoms and signs associated with consistently low testosterone concentrations. The diagnosis of testosterone deficiency is made by ascertainment of symptoms and signs; measurement of total and, if indicated, free testosterone levels, in early morning fasting samples on 2 or more days; measurement of LH and FSH to distinguish primary from secondary hypogonadism; and additional evaluation to ascertain the cause of testosterone deficiency. Non-specificity of symptoms and signs; variations in testosterone levels over time; inaccuracy in the measurement of total and free testosterone levels; variations in binding protein concentrations; and the suboptimal reference ranges contribute to diagnostic inaccuracy. Testosterone treatment is indicated for men with symptomatic testosterone deficiency. Testosterone treatment should be avoided in men with prostate or breast cancer, erythrocytosis, thrombophilia, increased risk of prostate cancer or severe lower urinary tract symptoms without prior urological evaluation, recent major adverse cardiovascular event, uncontrolled heart failure or severe untreated sleep apnea. Testosterone replacement therapy should be accompanied by a standardized monitoring plan.

CONCLUSION

The shared decision to treat should be guided by consideration of the burden of symptoms, potential benefits and risks, patient's values, and the cost and burden of long-term treatment and monitoring.

Is a fasting testosterone level really necessary for the determination of androgen status in men?

BACKGROUND

As circulating testosterone may be suppressed in the post-prandial state, it has been recommended that measurements are carried out with the patient fasted.

OBJECTIVES

In this regard, we assessed the effect of fasting/non-fasting status on total testosterone (T) levels in men.

MATERIALS AND METHODS

Data was collected in a single UK Hospital in men with two serum T requests taken within a 6-month period of each other and sampled at a time of day ≤ 2 h apart. Three groups were established, with T levels compared via signed-rank test in men with both a fasting and non-fasting sample (Group 1; n = 69), and in men with paired non-fasting (Group 2; n = 126) and paired fasting (Group 3; n = 18) samples. The differences in T levels between the paired samples was compared between the three groups using the rank-sum test and also via multiple regression analysis with the groups factorised.

RESULTS

Median (Interquartile Range, IQR) age did not vary significantly between Groups 1, 2 and 3 at 49 (38-56), 51.5 (42-60) and 51.5 (40-59) years, respectively. No significant difference (p = 0.89) was found between the T levels in Group 1 with non-fasting (median (IQR) T = 11.1 (9.3-13.6) nmol/L) versus fasting samples T = 10.8 (8.9-14.1) nmol/L). Paired T levels did not significantly differ in each of the other two groups (2 and 3). There was no significant association between the differences in paired T levels between the three groups, even when the model was adjusted for age and time, with Group 1 (as reference) versus Group 2 (p = 0.79) and versus Group 3 (p = 0.63).

DISCUSSION

We found no significant differences between fasting and non-fasting T levels. A definitive confirmatory study is required to determine whether fasting status is necessary to diagnose hypogonadism.

CONCLUSION

Non-requirement of fasting status when checking testosterone levels would remove a major hurdle in the diagnosis of hypogonadism.

Testosterone therapy with Testopel® and the Esoterix Laboratory assay: A CASE study

We present a patient receiving Testopel® implants whose serum testosterone levels, as measured by a CDC certified assay, were accurately predicted by a multi-compartmental model. This is the first time a model has predicted measured serum testosterone levels within 4% of values calculated. To our knowledge, it was also the first time a pharmacokinetic model allowed patient targeted serum levels (peak/trough/average) to be reached within three months.

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.

Male reproductive health in cystic fibrosis

The impact of cystic fibrosis (CF) on male reproductive health is profound. The vast majority of men with CF are infertile due to obstructive azoospermia. Multiple factors associated with CF contribute to an increased prevalence of testosterone deficiency, which adversely affects muscle mass, bone density, and quality of life. This article reviews the pathophysiology, diagnosis, and management of infertility and testosterone deficiency that occur in men with CF. With improving survival of CF patients, these topics are becoming more significant in their clinical care.

The Potential Effect of Aberrant Testosterone Levels on Common Diseases: A Mendelian Randomization Study

Testosterone has historically been linked to sexual dysfunction; however, it has recently been shown to affect other physical and mental attributes. We attempted to determine whether changes in serum testosterone could play a role in chronic or degenerative diseases. We used two separate genetic instruments comprising of variants from JMJD1C and SHBG regions and conducted a two-sample Mendelian randomization for type II diabetes (T2D), gout, rheumatoid arthritis (RA), schizophrenia, bipolar disorder, Alzheimer's disease and depression. For the JMJD1C locus, one unit increase in log transformed testosterone was significantly associated with RA (OR = 1.69, p = 0.02), gout (OR = 0.469, p = 0.001) and T2D (OR = 0.769, p = 0.048). Similarly, one unit increase in log transformed testosterone using variants from the SHBG locus was associated with depression (OR = 1.02, p < 0.0001), RA (OR = 1.254, p < 0.0001) and T2D (OR = 0.88, p < 0.0001). Our results show that low levels of serum testosterone levels may cause gout and T2D, while higher than normal levels of testosterone may result in RA and depression. Our findings suggest that fluctuations in testosterone levels may have severe consequences that warrant further investigation.

Preventing Lethal Prostate Cancer with Diet, Supplements, and Rx: Heart Healthy Continues to Be Prostate Healthy and "First Do No Harm" Part II

PURPOSE OF REVIEW

To discuss the overall and latest observations of the effect of diet, lifestyle, supplements, and some prescription heart healthy medications for prostate cancer prevention.

RECENT FINDINGS

The concept of maximizing heart health to prevent aggressive prostate cancer continues to be solidified with the addition of more prospective observational and randomized controlled trial data. Heart healthy is prostate healthy, and heart unhealthy is prostate unhealthy. The primary goal of reducing the risk of all-cause and cardiovascular disease (CVD) morbidity and mortality also coincides with maximizing prostate cancer prevention. The obesity epidemic in children and adults along with recent diverse research has only strengthened the nexus between heart and prostate health. Greater dietary adherence toward a variety of healthy foods is associated with a graded improved probability of CVD and potentially aggressive cancer risk reduction. Preventing prostate cancer via dietary supplements should encourage a "first do no harm," or less is more approach until future evidence can reverse the concerning trend that more supplementation has resulted in either no impact or an increased risk of prostate cancer. Supplements to reduce side effects of some cancer treatments appear to have more encouraging data. A discussion of quality (QC) before utilizing any pill also requires attention. Medications or interventions that potentially improve heart health including statins, aspirin, and metformin (S.A.M.), specific beta-blocker medications, and even preventive vaccines are in general generic, low-cost, "natural," and should continue to garner research interest. A watershed moment in medical education has arrived where the past perception of a diverse number of trees seemingly separated by vast distances, in reality, now appear to exist within the same forest.

The effects of age and obesity on postprandial dynamics of serum testosterone levels in men

OBJECTIVE

Guidelines recommend using fasting samples to evaluate testosterone (T) levels in men, as free and total T levels decrease postprandially. However, it is not clear whether these dynamics are affected by age or obesity. This could be relevant given the obesity epidemic, ageing population and the barrier for screening which fasting could impose.

DESIGN/PARTICIPANTS

A total of 43 men underwent a solid mixed meal tolerance test. Serum samples were taken fasting, and at 30, 60 and 120 minutes postprandially. A commercial immunoassay was used to determine sex hormone-binding globulin (SHBG) levels, liquid chromatography coupled to tandem mass spectroscopy for total T concentrations and free T levels were calculated.

RESULTS

Postprandially, both total and free T were lower at all-time points compared with fasting (all, P < .005). At 60 minutes, maximum mean decreases of 15 ± 15% and 17 ± 16% were seen for total and free T levels, respectively. Younger men had greater decreases in both total and free T levels compared with men older than 40 years (all, P < .05). A greater decrease at 30 and 60 minutes postprandially was observed for both total and free T levels in nonobese vs obese men (all, P < .05).

CONCLUSIONS

After a mixed meal, total and free T serum levels decreased whereas SHBG levels did not change. Interestingly, postprandial decreases were less pronounced in men older than 40 years and/or with obesity. Although this study indicates less pronounced decreases in certain men, fasting samples remain a prerequisite for establishing correct diagnosis of male hypogonadism.

The Effect of Macronutrients on Reproductive Hormones in Overweight and Obese Men: A Pilot Study

Hypogonadal obese men find it difficult to lose weight. We investigated whether the modification of macronutrient intake can alter testosterone levels independently of the body mass index. Fasted overweight or obese fertile men were asked to consume meals of polyunsaturated fats (PUFA), monounsaturated fats (MUFA), refined carbohydrates (CHO, orange juice, OJ), whey and egg albumin and mixed meals of PUFA and CHO, PUFA and egg albumin, and CHO and egg albumin. Blood was collected at fasting, then hourly for 5 h and analysed to determine the levels of testosterone and other hormones. We found PUFA and MUFA or a mixed meal of PUFA and CHO significantly reduced serum testosterone production to a similar degree over a 5 h period. PUFA decreased serum testosterone levels by 3.2 nmol/L after 1 h compared to baseline (p = 0.023), with this suppression remaining significant up to 5 h postprandially (2.1 nmol/L; p = 0.012). The net overall testosterone levels were reduced by approximately 10 nmol/L × h by PUFA, MUFA and PUFA combined with CHO. CHO alone had little effect on testosterone levels, whereas egg albumin was able to increase them (7.4 cf 2.0 nmol/L × h). Therefore, for men wishing to optimize their testosterone levels, it may be wise to avoid a high fat intake, drink liquids such as water or OJ or even consider fasting. ANZCTR, Australia; ACTRN12617001034325.

Testosterone Management in Aging Males: Surveying Clinical Practices of Urologists and Endocrinologists in Israel

Introduction

Although there is increased public concern about low testosterone levels in aging men, the diagnosis and treatment of hypogonadism in this growing population is controversial.

Aim

To document the current practices of endocrinologists and urologists in the management of older men with low testosterone in Israel.

Methods

A 20-question survey of the management of hypogonadism was sent to members of the Israel Endocrine Society and the Israeli Urology Association

Main Outcome Measures

Participants were interviewed about their practice in diagnostic workup, prescription habits and monitoring of testosterone therapy.

Results

The response rate was low (range 8–12%). Significant differences were found between members of the 2 professional associations. Overall, endocrinologists take a more conservative approach to the diagnosis and initial workup, modes of treatment, and to concerns about the safety of testosterone therapy. A divergence from the published clinical guidelines was also noted in some aspects of the clinical practices in both groups.

Clinical Implications

Significant variances in the diagnosis and treatment approach of hypogonadism between endocrinologists and urologists, as well as divergences from clinical guidelines, may lead to misuse of testosterone therapy.

Strengths & Limitations

This is the first study undertaken in Israel among urologists and endocrinologists of this increasingly recognized health issue. In our country, these 2 groups of physicians comprise nearly all of the testosterone treatment providers. The limitation of this study is linked to bias of all surveys based on subjective reporting, the fact that it was performed in only 1 country, and that we did not control for the specific assay used to measure testosterone levels.

Conclusions

These findings highlight the need for the implementation of coordinated guidelines to facilitate the appropriate diagnosis and treatment of men who can benefit from testosterone therapy and to minimize the risks of this therapy.

Ishay A, Tzemah S, Nitzan R, et al. Testosterone Management in Aging Males: Surveying Clinical Practices of Urologists and Endocrinologists in Israel. Sex Med 2019;7:409–417.

Obesity and male hypogonadism: Tales of a vicious cycle

Obesity prevalence, particularly in children and young adults, is perilously increasing worldwide foreseeing serious negative health impacts in the future to come. Obesity is linked to impaired male gonadal function and is currently a major cause of hypogonadism. Besides signs and symptoms directly derived from decreased circulating testosterone levels, males with obesity also present poor fertility outcomes, further evidencing the parallelism between obesity and male reproductive function. In addition, males with androgen deficiency also exhibit increased fat accumulation and reduced muscle and mineral bone mass. Thus, compelling evidence highlights a vicious cycle where male hypogonadism can lead to increased adiposity, while obesity can be a cause for male hypogonadism. On the opposite direction, sustained weight loss can attain amelioration of male gonadal function. In this scenario, a thorough evaluation of gonadal function in men with obesity is crucial to dissect the causes from the consequences in order to target clinical interventions towards maximized improvement of reproductive health. This review will address the causes and consequences of the bidirectional relationship between obesity and hypogonadism, highlighting the implicit male reproductive repercussions.

Acute decrease in plasma testosterone and appetite after either glucose or protein beverages in adolescent males

OBJECTIVE

Chronic testosterone blood concentrations associate with food intake (FI), but acute effects of testosterone on appetite and effect of protein and glucose consumption on testosterone response have had little examination.

METHODS

In a randomized, crossover study, twenty-three adolescent (12-18 years old) males were given beverages containing either: (a) whey protein (1 g/kg body weight), (b) glucose (1 g/kg body weight) or (c) a calorie-free control (C). Plasma testosterone, luteinizing hormone (LH), GLP-1 (active), ghrelin (acylated), glucose, insulin and subjective appetite were measured prior (0) and at 20, 35 and 65 minutes after the consumption of the beverage. FI at an ad libitum pizza meal was assessed at 85 minutes.

RESULTS

Testosterone decreased acutely to 20 minutes after both protein and glucose with the decrease continuing after protein but not glucose to 65 minutes (P = 0.0382). LH was also decreased by both protein and glucose, but glucose had no effect at 20 minutes in contrast to protein (P < 0.001). Plasma testosterone concentration correlated positively with LH (r = 0.58762, P < 0.0001) and negatively with GLP-1 (r = -0.50656, P = 0.0003). No associations with appetite, ghrelin or glycaemic markers were found. Food intake was not affected by treatments.

CONCLUSION

Protein or glucose ingestion results in acute decreases in both plasma testosterone and LH in adolescent males. The physiological significance of this response remains to be determined as no support for testosterone's role in acute regulation of food intake was found.

Testosterone and the Heart

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

Investigation and management of subfertility

Subfertility affects one in seven couples and is defined as the inability to conceive after 1 year of regular unprotected intercourse. This article describes the initial clinical evaluation and investigation to guide diagnosis and management. The primary assessment of subfertility is to establish the presence of ovulation, normal uterine cavity and patent fallopian tubes in women, and normal semen parameters in men. Ovulation is supported by a history of regular menstrual cycles (21-35 days) and confirmed by a serum progesterone >30 nmol/L during the luteal phase of the menstrual cycle. Common causes of anovulation include polycystic ovary syndrome (PCOS), hypothalamic amenorrhoea (HA) and premature ovarian insufficiency (POI). Tubal patency is assessed by hysterosalpingography, hystero-contrast sonography, or more invasively by laparoscopy and dye test. The presence of clinical or biochemical hyperandrogenism, serum gonadotrophins (luteinising hormone/follicle stimulating hormone) / oestradiol, pelvic ultrasound to assess ovarian morphology / antral follicle count, can help establish the cause of anovulation. Ovulation can be restored in women with PCOS using letrozole (an aromatase inhibitor), clomifene citrate (an oestrogen antagonist) or exogenous gonadotrophin administration. If available, pulsatile gonadotrophin releasing hormone therapy is the preferred option for restoring ovulation in HA. Spermatogenesis can be induced in men with hypogonadotrophic hypogonadism with exogenous gonadotrophins. Unexplained subfertility can be treated with in vitro fertilisation after 2 years of trying to conceive. Involuntary childlessness is associated with significant psychological morbidity; hence, expert assessment and prompt treatment are necessary to support such couples.

Investigating the basis of sexual dysfunction during late-onset hypogonadism

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

A Short Study Exploring the Effect of the Glycaemic Index of the Diet on Energy intake and Salivary Steroid Hormones

Background: The glycaemic index or load (GI or GL) is a concept for ranking carbohydrate-rich foods based on the postprandial blood glucose response compared with a reference food (glucose). Due to the limited research investigating the effect of the GI or GL of the diet on salivary steroidal hormones, this explorative short study was conducted. Methods: 12 female participants consumed a low GI and a high GI diet for three days each, followed by a washout period between each intervention. Saliva was collected at baseline, and following the low or high GI diets. Cortisol and testosterone concentrations were measured by enzyme-linked immuno-sorbent assay (ELISA). Results: GI and GL were significantly different between the low and high GI diets (p < 0.001). There was a small but significant increase in salivary cortisol after the high GI diet (7.38 to 10.93 ng/mL, p = 0.036). No effect was observed after the low GI diet. Higher levels of testosterone were produced after the low GI diet (83.7 to 125.9 pg/mL, p = 0.002), and no effect was found after the high GI diet. The total intake of calories consumed on the low GI diet was significantly lower compared to the high GI diet (p = 0.019). Conclusions: A low GI diet was associated with a small but significant increase in salivary testosterone, while a high GI diet increased cortisol levels. Altering the GI of the diet may influence overall energy intake and the health and wellbeing of female volunteers.

Oral glucose load and mixed meal feeding lowers testosterone levels in healthy eugonadal men

PURPOSE

Precise evaluation of serum testosterone levels is important in making an accurate diagnosis of androgen deficiency. Recent practice guidelines on male androgen deficiency recommend that testosterone be measured in the morning while fasting. Although there is ample evidence regarding morning measurement of testosterone, studies that evaluated the effect of glucose load or meals were limited by inclusion of hypogonadal or diabetic men, and measurement of testosterone was not performed using mass spectrometry.

METHODS

Sixty men (23-97 years) without pre-diabetes or diabetes who had normal total testosterone (TT) levels underwent either an oral glucose tolerance test (OGTT) or a mixed meal tolerance test (MMTT) after an overnight fast. Serum samples were collected before and at regular intervals for 2 h (OGTT cohort) or 3 h (MMTT cohort). TT was measured by LC-MS/MS. LH and prolactin were also measured.

RESULTS

TT decreased after a glucose load (mean drop at nadir = 100 ng/dL) and after a mixed meal (drop at nadir = 123 ng/dL). Approximately 11% of men undergoing OGTT and 56% undergoing MMTT experienced a transient decrease in TT below 300 ng/dL, the lower normal limit. Testosterone started declining 20 min into the tests, with average maximum decline at 60 min. Most men still had TT lower than baseline at 120 min. This effect was independent of changes in LH or prolactin.

CONCLUSION

A glucose load or a mixed meal transiently, but significantly, lowers TT levels in healthy, non-diabetic eugonadal men. These findings support the recommendations that measurement of serum testosterone to diagnose androgen deficiency should be performed while fasting.

Testosterone replacement therapy: For whom, when and how?

The finding of low circulating testosterone level in men is relatively frequent. The symptoms of hypogonadism are very frequent in the aging men. However, the diagnosis of hypogonadism is often neglected and the opportunity to replace low testosterone in older men is highly debated. The aim of this narrative review is to summarize the steps necessary to formulate a proper diagnosis and to guide toward an individualized treatment. While universally recognized the need to treat the young adults with known causes of pituitary or testicular failure, there are controversies on the cost-benefit of treating testosterone deficiency in older men. Discrepancies among the several available guidelines do not help to clarify the scenario, however, the recent larger clinical trials have shed some light on the fact that testosterone treatment carries some benefit, that is not free from risks. We provide an updated review of the diagnostic hallmarks, the several treatment modalities, with their advantages and disadvantages, and how to individualize and monitor treatment in order to maximize the benefits and minimize the risks. The treatment of male hypogonadism can no longer be downgraded and must become part of the cultural baggage of the endocrinologist.

Sugar-sweetened beverage intake and serum testosterone levels in adult males 20-39 years old in the United States

BACKGROUND

This population-based study was designed to investigate whether consumption of sugar-sweetened beverages (SSB) is associated with lower serum total testosterone concentration in men 20-39 years old.

METHODS

All data for this study were retrieved from the National Health and Nutrition Examination Survey (NHANES) 2011-2012. The primary outcome was serum testosterone concentration, and main independent variable was SSB intake. Other variables included age, race/ethnicity, poverty/income ratio, body mass index (BMI), serum cotinine, heavy drinking, and physical activity.

RESULTS

Among all subjects (N = 545), 486 (90.4%) had normal testosterone levels (defined as ≥231 ng/dL) and 59 (9.6%) had low testosterone levels (defined as < 231 ng/dL). Multivariate logistic regression revealed the odds of low testosterone was significantly greater with increasing SSB consumption (Q4 [≥442 kcal/day] vs. Q1 [≤137 kcal/day]), adjusted odds ratio [aOR] = 2.29, p = 0.041]. After adjusting for possible confounding variables, BMI was an independent risk factor for low testosterone level; subjects with BMI ≥ 25 kg/m² had a higher risk of having a low testosterone level than those with BMI < 25 kg/m² (aOR = 3.68, p = 0.044).

CONCLUSION

SSB consumption is significantly associated with low serum testosterone in men 20-39 years old in the United States.

Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline

OBJECTIVE

To update the "Testosterone Therapy in Men With Androgen Deficiency Syndromes" guideline published in 2010.

PARTICIPANTS

The participants include an Endocrine Society-appointed task force of 10 medical content experts and a clinical practice guideline methodologist.

EVIDENCE

This evidence-based guideline was developed using the Grading of Recommendations, Assessment, Development, and Evaluation approach to describe the strength of recommendations and the quality of evidence. The task force commissioned two systematic reviews and used the best available evidence from other published systematic reviews and individual studies.

CONSENSUS PROCESS

One group meeting, several conference calls, and e-mail communications facilitated consensus development. Endocrine Society committees and members and the cosponsoring organization were invited to review and comment on preliminary drafts of the guideline.

CONCLUSIONS

We recommend making a diagnosis of hypogonadism only in men with symptoms and signs consistent with testosterone (T) deficiency and unequivocally and consistently low serum T concentrations. We recommend measuring fasting morning total T concentrations using an accurate and reliable assay as the initial diagnostic test. We recommend confirming the diagnosis by repeating the measurement of morning fasting total T concentrations. In men whose total T is near the lower limit of normal or who have a condition that alters sex hormone-binding globulin, we recommend obtaining a free T concentration using either equilibrium dialysis or estimating it using an accurate formula. In men determined to have androgen deficiency, we recommend additional diagnostic evaluation to ascertain the cause of androgen deficiency. We recommend T therapy for men with symptomatic T deficiency to induce and maintain secondary sex characteristics and correct symptoms of hypogonadism after discussing the potential benefits and risks of therapy and of monitoring therapy and involving the patient in decision making. We recommend against starting T therapy in patients who are planning fertility in the near term or have any of the following conditions: breast or prostate cancer, a palpable prostate nodule or induration, prostate-specific antigen level > 4 ng/mL, prostate-specific antigen > 3 ng/mL in men at increased risk of prostate cancer (e.g., African Americans and men with a first-degree relative with diagnosed prostate cancer) without further urological evaluation, elevated hematocrit, untreated severe obstructive sleep apnea, severe lower urinary tract symptoms, uncontrolled heart failure, myocardial infarction or stroke within the last 6 months, or thrombophilia. We suggest that when clinicians institute T therapy, they aim at achieving T concentrations in the mid-normal range during treatment with any of the approved formulations, taking into consideration patient preference, pharmacokinetics, formulation-specific adverse effects, treatment burden, and cost. Clinicians should monitor men receiving T therapy using a standardized plan that includes: evaluating symptoms, adverse effects, and compliance; measuring serum T and hematocrit concentrations; and evaluating prostate cancer risk during the first year after initiating T therapy.

Metabolic phenotype of male obesity-related secondary hypogonadism pre-replacement and post-replacement therapy with intra-muscular testosterone undecanoate therapy

AIM

To explore the metabolic phenotype of obesity-related secondary hypogonadism (SH) in men pre-replacement and post-replacement therapy with long-acting intramuscular (IM) testosterone undecanoate (TU).

METHODS

A prospective observational pilot study on metabolic effects of TU IM in male obesity-related SH (hypogonadal [HG] group, n = 13), including baseline comparisons with controls (eugonadal [EG] group, n = 15). Half the subjects (n = 7 in each group) had type 2 diabetes mellitus (T2D). Baseline metabolic assessment on Human Metabolism Research Unit: fasting blood samples; BodPod (body composition), and; whole-body indirect calorimetry. The HG group was treated with TU IM therapy for 6-29 months (mean 14.8-months [SD 8.7]), and assessment at the Human Metabolism Research Unit repeated. T-test comparisons were performed between baseline and follow-up data (HG group), and between baseline data (HG and EG groups). Data reported as mean (SD).

RESULTS

Overall, TU IM therapy resulted in a statistically significant improvement in HbA1C (9 mmol/mol, P = 0.03), with 52% improvement in HOMA%B. Improvement in glycaemic control was driven by the HG subgroup with T2D, with 18 mmol/mol [P = 0.02] improvement in HbA1C. Following TU IM therapy, there was a statistically significant reduction in fat mass (3.5 Kg, P = 0.03) and increase in lean body mass (2.9 kg, P = 0.03). Lipid profiles and energy expenditure were unchanged following TU IM therapy. Comparisons between baseline data for HG and EG groups were equivalent apart from differences in testosterone, SHBG and basal metabolic rate (BMR).

CONCLUSION

In men with obesity-related SH (including a subgroup with T2D), TU IM therapy improved glycaemic control, beta cell function, and body composition.

High risk of hypogonadism in young male cancer survivors

OBJECTIVE

Cancer and its treatment in childhood and young adulthood can cause hypogonadism, leading to increased risk of long-term morbidity and mortality. The aim of this study was to evaluate the risk of presenting with biochemical signs of hypogonadism in testicular cancer survivors (TCS) and male childhood cancer survivors (CCS) in relation to the type of treatment given.

DESIGN

Case-control study.

PATIENTS

Ninety-two TCS, 125 CCS (mean age 40 and median age 34 years, respectively; mean follow-up time 9.2 and 24 years, respectively) and a corresponding number of age-matched controls.

MEASUREMENTS

Fasting morning blood samples were analysed for total testosterone (TT), follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The odds ratios (OR) for hypogonadism, defined as primary, secondary, compensated or ongoing androgen replacement, were calculated for TCS and CCS and for subgroups defined by diagnosis and treatment.

RESULTS

Hypogonadism was found in 26% of CCS and 36% of TCS, respectively (OR: 2.1, P = .025 and OR = 2.3, P = .021). Among CCS, the OR was further increased in those given testicular irradiation (OR = 28, P = .004). Radiotherapy other than cranial or testicular irradiation plus chemotherapy, or cranial irradiation without chemotherapy, associated also with increased ORs (OR = 3.7, P = .013, and OR = 4.4, P = .038, respectively). Among TCS, those receiving >4 cycles of cisplatin-based chemotherapy had OR = 17, P = .015.

CONCLUSIONS

Biochemical signs of testosterone deficiency are recognized as markers of decreased life expectancy. Thus, the risk of hypogonadism in TCS and CCS should be recognized and emphasizes the need of long-term follow-up for these men.

Testosterone therapy for sexual dysfunction in men with Type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials

AIM

To evaluate the effectiveness of testosterone therapy on a range of sexual function domains in men with Type 2 diabetes.

METHOD

Electronic databases were searched for studies investigating the effect of testosterone therapy on sexual function in men with Type 2 diabetes. All randomized controlled trials were considered for inclusion if they compared the efficacy of testosterone therapy with that of placebo and reported sexual function outcomes. Statistical analysis was performed using a random-effects model, and heterogeneity was expressed using the I² statistic.

RESULTS

A total of 611 articles were screened. Six randomized control trials, in a total of 587 men with Type 2 diabetes, were eligible for inclusion. The pooled data suggested that testosterone therapy improves sexual desire (random-effects pooled effect size 0.314; 95% CI 0.082-0.546) and erectile function (random-effects pooled effect size 0.203; 95% CI 0.007-0.399) when compared with control groups. Testosterone therapy had no significant effect on constitutional symptoms or other sexual domains compared with control groups. No studies have investigated the incidence of prostate cancer, fertility and cardiovascular disease after testosterone therapy in men with Type 2 diabetes.

CONCLUSION

Testosterone therapy may moderately improve sexual desire and erectile function in men with Type 2 diabetes; however, available data are limited, and the long-term risks of testosterone therapy are not known in this specific patient group. We conclude that testosterone therapy is a potential treatment for men with Type 2 diabetes non-responsive to phosphodiesterase-5 inhibitors. Testosterone therapy could be considered for men with Type 2 diabetes when potential risks and benefits of therapy are carefully considered and other therapeutic options are unsuitable.