Hypogonadism and male obesity: Focus on unresolved questions

The ketogenic diet corrects metabolic hypogonadism and preserves pancreatic ß-cell function in overweight/obese men: a single-arm uncontrolled study

BACKGROUND

Overweight and obesity are increasingly spread in our society. Low testosterone levels are often present in these patients, the so-called metabolic hypogonadism, that further alters the metabolic balance in a sort of vicious cycle. Very low-calorie ketogenic diet (VLCKD) has been reported to efficiently reduce body weight, glycaemia, and the serum levels of insulin, glycated hemoglobin, but its effects on β-cell function and total testosterone (TT) levels are less clear.

AIM

To evaluate the effects of VLCKD on markers suggested to be predictive of β-cell dysfunction development, such as proinsulin or proinsulin/insulin ratio, and on TT values in a cohort of overweight or obese nondiabetic male patients with metabolic hypogonadism.

METHODS

Patients with overweight or obesity and metabolic hypogonadism underwent to VLCKD for 12 weeks. Anthropometric parameters, blood testing for the measurement of glycaemia, insulin, C-peptide, proinsulin, TT, calculation of body-mass index (BMI), and HOMA index were performed before VLCKD and after 12 weeks.

RESULTS

Twenty patients (mean age 49.3 ± 5.2 years) were enrolled. At enrollement all patients presented increased insulin, HOMA index, C-peptide, and proinsulin levels, whereas the proinsulin/insulin ratio was within the normal values. After VLCKD treatment, body weight and BMI significantly decreased, and 14.9 ± 3.9% loss of the initial body weight was achieved. Glycaemia, insulin, HOMA index, C-peptide, and proinsulin significantly decreased compared to pre-VLCKD levels. Serum glycaemia, insulin, C-peptide, and proinsulin levels returned within the normal range in all patients. No difference in the proinsulin/insulin ratio was observed after VLCKD treatment. A mean increase of 218.1 ± 53.9% in serum TT levels was achieved and none of the patients showed TT values falling in the hypogonadal range at the end of the VLCKD treatment.

CONCLUSIONS

This is the first study that evaluated the effects of VLCKD on proinsulin, proinsulin/insulin ratio, and TT levels. VLCKD could be safely used to improve β-cell secretory function and insulin-sensitivity, and to rescue overweight and obese patients from β-cell failure and metabolic hypogonadism.

Composite Indices of Femoral Neck Strength in Middle-Aged Inactive Subjects Vs Former Football Players

The purpose of this study was to compare composite indices of femoral neck strength ((compression strength index [CSI], bending strength index [BSI], and impact strength index [ISI]) in inactive middle-aged men (n = 20) and middle-aged former football players (n = 15). 35 middle-aged men participated in this study. Body composition and bone variables were evaluated by dual-energy X-ray absorptiometry. Composite indices of femoral neck strength (CSI, BSI, and ISI) were calculated. Handgrip strength, vertical jump, maximum power of the lower limbs (watts), horizontal jump, maximal half-squat strength, maximal bench-press strength, sprint performance (10 meters), and maximum oxygen consumption (VO₂ max, ml/min/kg) were evaluated using validated tests. CSI, BSI, and ISI were significantly higher in football players compared to inactive men. Vertical jump, horizontal jump, maximal half-squat strength, VO₂ max and sprint performance were significantly different between the 2 groups. CSI, BSI, and ISI remained significantly higher in football players compared to inactive men after adjusting for physical activity level. The current study suggests that former football practice is associated with higher composite indices of femoral neck strength in middle-aged men.

Cross Sectional Study among Intraocular Pressure, Mean Arterial Blood Pressure, and Serum Testosterone according to the Anthropometric Obesity Indices in Korean Men

Purpose

To investigate the association between intraocular pressure (IOP) and serum testosterone according to the severity of obesity.

Materials and Methods

We investigated the correlation of IOP-testosterone according to the anthropometric obesity indices, such as obesity index (OI), body mass index (BMI), and waist circumference to height ratio (WtHR). Each of the obesity indices was classified into three groups: normal, overweight, and obesity. In additional, the association of IOP-testosterone was compared between testosterone 3.0 ng/mL below and above.

Results

Total of 3,949 participants, the mean age was 58.86±10.06 years, mean IOP was 14.40±2.61 mmHg, mean arterial blood pressure (MAP) was 93.67±11.47 mmHg, and mean serum testosterone was 4.21±1.83 ng/mL. The association of MAP and IOP was significantly positively correlated according to the severity of obesity, but testosterone showed a significant negative relationship (p<0.05). IOP was significantly correlated with OI and BMI, but MAP and testosterone were correlated with all anthropometric obesity indices (p<0.05). The relationship of IOP and testosterone was significantly associated with only normal groups according to the degree of obesity (p<0.05). The IOP in patients with testosterone above 3.0 ng/mL was significantly higher than testosterone below 3.0 ng/mL (p<0.05).

Conclusions

The correlation of IOP-testosterone has a significantly positive relationship, in case of healthy men with normal weight by OI or BMI.

Testosterone treatment in male patients with Klinefelter syndrome: a systematic review and meta-analysis

PURPOSE

Low testosterone (T) in Klinefelter's syndrome (KS) can contribute to typical features of the syndrome such as reduced bone mineral density, obesity, metabolic disturbances and increased cardiovascular risk. The aim of the present study is to review and meta-analyze all available information regarding possible differences in metabolic and bone homeostasis profile between T treated (TRT) or untreated KS and age-matched controls.

METHODS

We conducted a random effect meta-analysis considering all the available data from observational or randomized controlled studies comparing TRT-treated and untreated KS and age-matched controls. Data were derived from an extensive MEDLINE, Embase, and Cochrane search.

RESULTS

Out of 799 retrieved articles, 21 observational and 22 interventional studies were included in the study. Retrieved trials included 1144 KS subjects and 1284 healthy controls. Not-treated KS patients showed worse metabolic profiles (including higher fasting glycemia and HOMA index as well as reduced HDL-cholesterol and higher LDL-cholesterol) and body composition (higher body mass index and waist circumference) and reduced bone mineral density (BMD) when compared to age-matched controls. TRT in hypogonadal KS subjects was able to improve body composition and BMD at spinal levels but it was ineffective in ameliorating lipid and glycemic profile. Accordingly, TRT-treated KS subjects still present worse metabolic parameters when compared to age-matched controls.

CONCLUSION

TRT outcomes observed in KS regarding BMD, body composition and glyco-metabolic control, are similar to those observed in male with hypogonadism not related to KS. Moreover, body composition and BMD are better in treated than untreated hypogonadal KS. Larger and longer randomized placebo-controlled trials are advisable to better confirm the present data, mainly derived from observational studies.

MiR-130a in the adipogenesis of human SGBS preadipocytes and its susceptibility to androgen regulation

Objectives: Adipogenesis is the differentiation process generating mature adipocytes from undifferentiated mesenchymal stem cells. The differentiation can be inhibited by androgens, although knowledge about intracellular effectors of this inhibition is scarce. Recently, androgen-regulated microRNAs were detected as interesting candidates in this context. In this study, we analyse the role of miR-130a and miR-301 in the adipogenesis of human SGBS preadipocytes and whether they are prone to androgen regulation. Materials and Methods: microRNA expression during adipogenic differentiation with or without androgen stimulation was measured by qPCR. Putative target genes of miR-130a and miR-301 were identified by target database search and validated in luciferase reporter assays. Results: miR-130a and miR-301 are both significantly downregulated on day 3 and day 5 of adipogenic differentiation in comparison to day 0. Under androgen stimulation, a significant upregulation of miR-130a was detected after 7 days of adipogenesis lasting to day 14, while miR-301 did not change significantly until day 14. Luciferase reporter assays revealed the androgen receptor (AR), adiponectin (ADIPOQ) and tumour necrosis factor alpha (TNFα) as miR-130a target genes. Conclusions: miR-130a is an androgen-regulated microRNA that is downregulated during the early phase of adipogenesis and exerts its functions by regulating AR and ADIPOQ translation. These data may help to identify new signalling pathways associated with the androgen-mediated inhibition of adipogenesis.

The association between body mass index and testosterone deficiency in aging Chinese men with benign prostatic hyperplasia: results from a cross-sectional study

BACKGROUND AND OBJECTIVES

Evidence has supported obesity as a risk factor for both benign prostate hyperplasia (BPH) and hypogonadism. In this paper, we performed a retrospective study and discussed the prevalence of testosterone deficiency (TD) and its relationship to body mass index (BMI) in aging Chinese men with BPH who have surgical intervention.

MATERIAL AND METHODS

We reviewed the clinical data by age, BMI, medical history, serum prostate-specific antigen (PSA) levels, serum total testosterone (TT) levels, biochemical analysis, and transrectal ultrasound. BMI and other variables were considered to be independent variables in an effort to evaluate any potential associations between these factors and TD status using non-adjusted and multivariate-adjusted regression models.

RESULTS

Of the 795 BPH participants, 27.2% (216) patients had TD. After adjusting for all potential covariates, there was a similar J-shaped relationship between BMI and TD, with an inflection point of 19.2 kg/m². The effect sizes and the confidence intervals on the left and right sides of this inflection point were 0.6 (0.4-1.0) (p = .043) and 1.2 (1.1-1.3) (p < .001), respectively.

CONCLUSION

Nearly one-third of the aging Chinese BPH patients had TD in this study. The association between BMI and TD is not simple. A J-shaped curve correlation was detected. BMI was positively correlated with TD when it was over 19.2 kg/m² and inversely correlated with TD when it was below 19.2 kg/m². Long-term prospective studies are needed to confirm these findings.

Examining the association between serum free fatty acids and blood levels of testosterone

BACKGROUND

Multiple studies have uncovered the effects that ingested fat has on human blood levels of testosterone. Yet, few reports have discussed the effect of circulating serum free fatty acids (FFAs). The present study aimed to explore the relationship between serum free fatty acids and blood levels of testosterone.

METHODS

In total, 5719 adults were pooled from the database of the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2012. Based on multivariable-linear regression models, we employed a total of 30 FFAs to interpret the relationship of FFAs with blood levels of testosterone. Two models with covariate adjustments were designated for further evaluation and analysis.

RESULTS

Capric acid [β = -0.014, 95% confidence interval (CI) = -0.023, -0.004, P = 0.005], myristic acid (β = -0.001, 95% CI = -0.001, 0.000, P ≤ 0.001), pentadecanoic acid (β = -0.013, 95% CI = -0.018, -0.008, P ≤ 0.001), margaric acid (β = -0.011, 95% CI = -0.017, -0.005, P ≤ 0.001) and alpha-linolenic acid (β = -0.001, 95% CI = -0.002, 0.000, P = 0.004) in the fully adjusted model were significantly negatively correlated with the testosterone level inh obese men. In the fully adjusted model for the female analysis, myristic acid, pentadecanoic acid, palmitic acid, margaric acid, stearic acid, myristoleic acid, oleic acid, nervonic acid and alpha-linolenic acid were found significantly associated with the testosterone level.

CONCLUSIONS

Our findings indicate a significant negative correlation between serum FFAs and blood levels of testosterone. Furthermore, we reveal the essentiality of serum FFAs and their potential effects on the reduction of testosterone levels.

SHBG and total testosterone levels in men with adult onset hypogonadism: what are we overlooking?

Background

Adult onset male hypogonadism (AOH) is a common clinical condition whose diagnosis and management are controversial, and is often characterized by a low level of SHBG, but our understanding of why testosterone levels are low when SHBG is low is incomplete.

Methods

This retrospective chart review was performed to compare the relationship between SHBG and testosterone in the plasma of men presenting for evaluation of AOH with a cohort of men treated chronically with transdermal testosterone.

Results

The level of SHBG was < 30 nmol/L in 73% of men who presented for evaluation of AOH, and was inversely proportional to BMI in both the untreated and the testosterone-treated men. As in previous populations, the level of SHBG was highly positively correlated (r = 0.71, p < 0.01) with the total testosterone level in untreated men presenting for evaluation of AOH, but no relationship was found between the level of SHBG and total testosterone among men who were being treated with a transdermal testosterone preparation.

Conclusions

These findings further support the idea that SHBG regulates testicular negative feedback either directly or by modulating the entry of testosterone or estradiol into cells in the hypothalamus and/or pituitary to control gonadotropin synthesis and secretion which explains in part the low testosterone levels in men with AOH.

Trial registration

Not applicable.

Estradiol, obesity and hypogonadism

Obesity increases the incidence of hypogonadism in men, and hypogonadism in turn plays a role in obesity. One of the first mechanisms proposed to explain this was a hypothesis based on the principle that obese men have higher estrogen levels, and that increased estrogens provide feedback to the hypothalamic-pituitary-testicular axis, reducing the secretion of gonadotropins and leading to a decrease of overall testosterone levels. This concept has since been questioned, though never completely disproven. In this study we compared hormone levels in three groups of men with differing BMI levels (between 18-25, 25-29, and 30-39), and found correlations between lowering overall testosterone, SHBG and increased BMI. At the same time, there were no significant changes to levels of free androgens, estradiol or the gonadotropins LH and FSH. These findings are in line with the idea that estrogen production in overweight and obese men with BMI up to 39 kg/m(2) does not significantly influence endocrine testicular function.

Testosterone for Androgen Deficiency-Like Symptoms in Men Without Pathologic Hypogonadism: A Randomized, Placebo-Controlled Cross-over With Masked Choice Extension Clinical Trial

BACKGROUND

Off-label testosterone prescribing for androgen deficiency (AD)-like sexual and energy symptoms of older men without pathologic hypogonadism has increased dramatically without convincing evidence of efficacy.

METHODS

In a randomized, double-blind, placebo-controlled study with three phases, we entered 45 men aged at least 40 years without pathologic hypogonadism but with AD-like energy and/or sexual symptoms to either daily testosterone or placebo gel treatment for 6 weeks in a cross-over study design with a third, mandatory extension phase in which participants chose which previous treatment they preferred to repeat while remaining masked to their original treatment. Primary endpoints were energy and sexual symptoms as assessed by a visual analog scale (Lead Symptom Score [LSS]).

RESULTS

Increasing serum testosterone to the healthy young male range produced no significant benefit more than placebo for energy or sexual LSS. Covariate effects of age, body mass index, and pretreatment baseline serum testosterone on quality-of-life scales were detected. Only 1 out of 22 indices from seven quality-of-life scales was significantly improved by testosterone treatment over placebo. Participants did not choose testosterone significantly more than placebo as their preferred treatment in the third phase.

CONCLUSIONS

Six-week testosterone treatment does not improve energy or sexual symptoms more than placebo in symptomatic men without pathologic hypogonadism.

Pre-operative Obesity-Associated Hyperandrogenemia in Women and Hypogonadism in Men Have No Impact on Weight Loss Following Bariatric Surgery

Background

In severe obesity, hypogonadism in men and androgen excess in women are frequently observed. Sex hormones play an important role in body composition and glucose and lipid metabolism. However, whether pre-operative gonadal dysfunction impacts weight loss after bariatric surgery is not fully known.

Methods

A total of 49 men and 104 women were included in a retrospective analysis. Anthropometric characteristics, glucose and lipid metabolism, and androgen concentrations were assessed pre-operatively and 17.9 ± 11 or 19.3 ± 12 months post-operatively in men and women. Men with (HYPO_male) and without (controls: CON_male) pre-operative hypogonadism, as well as women with (HYPER_female) and without (controls: CON_female) pre-operative hyperandrogenemia, were compared.

Results

In men, pre-operative hypogonadism was present in 55% and linked to a higher body mass index (BMI): HYPO_male 50 ± 6 kg/m² vs. CON_male 44 ± 5 kg/m², p = 0.001. Bariatric surgery results in comparable changes in BMI in HYPO_male and CON_male − 16 ± 6 kg/m² vs. − 14 ± 5 kg/m², p = 0.30. Weight loss reversed hypogonadism in 93%. In women, androgen excess was present in 22%, independent of pre-operative BMI: CON_female 44 ± 7 kg/m² vs. HYPER_female 45 ± 7 kg/m², p = 0.57. Changes in BMI were comparable in HYPER_female and CON_female after bariatric surgery − 15 ± 6 kg/m² vs. − 15 ± 5 kg/m², p = 0.88. Hyperandrogenemia was reversed in 61%.

Conclusions

Besides being frequently observed, hypogonadism in men and androgen excess in women have no impact on post-surgical improvements in body weight and glucose and lipid metabolism. Weight loss resulted in reversal of hypogonadism in almost all men and of hyperandrogenemia in the majority of women.

European Academy of Andrology (EAA) guidelines on investigation, treatment and monitoring of functional hypogonadism in males: Endorsing organization: European Society of Endocrinology

BACKGROUND

Evidence regarding functional hypogonadism, previously referred to as 'late-onset' hypogonadism, has increased substantially during the last 10 year.

OBJECTIVE

To update the European Academy of Andrology (EAA) guidelines on functional hypogonadism.

METHODS

Expert group of academicians appointed by the EAA generated a series of consensus recommendations according to the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) system.

RESULTS

The diagnosis of functional hypogonadism should be based on both the presence of clinical symptoms supported by repeatedly low morning fasting serum total testosterone (T) measured with a well-validated assay, after exclusion of organic causes of hypogonadism. Lifestyle changes and weight reduction should be the first approach in all overweight and obese men. Whenever possible, withdrawal/modification of drugs potentially interfering with T production should be advised. Testosterone replacement therapy (TRT) is contraindicated in men with untreated prostate or breast cancer, as well as severe heart failure. Severe low urinary tract symptoms and haematocrit >48%-50% represent relative contraindications for TRT. Prostate-specific antigen and digital rectal examination of the prostate should be undertaken in men >40 years of age before initiating TRT to exclude occult prostate cancer. Transdermal T should be preferred for initiation of TRT, whereas gonadotrophin therapy is only recommended when fertility is desired in men with secondary hypogonadism. TRT is able to improve sexual function in hypogonadal men. Other potential positive outcomes of TRT remain uncertain and controversial.

CONCLUSION

TRT can reliably improve global sexual function in men with hypogonadism in the short term. Long-term clinical benefits, and safety of TRT in functional hypogonadism, remain to be fully documented. Clinicians should therefore explicitly discuss the uncertainties and benefits of TRT and engage them in shared management decision-making.

Obesity and Baseline Estradiol Levels Are Independent Predictors for Initiation of Anastrozole in Hypogonadal Men on Clomiphene Citrate

PURPOSE

To assess the conversion rate from clomiphene citrate (CC) monotherapy to combination CC+anastrozole (AZ) therapy in hypogonadal men and the predictors associated with the initiation of AZ.

MATERIALS AND METHODS

A retrospective review of records from hypogonadal men treated with CC in a single fertility center was performed from 2013 to 2018. Patient age, body mass index (BMI), blood pressure, and reproductive hormones were obtained at baseline. Obesity was defined as BMI≥30 kg/m². Cox proportional hazards models were used to identify predictors of switching to combination CC+AZ therapy.

RESULTS

A total of 318 men on CC were included. Median (interquartile range) age was 34 years (30-39 years) and patients were followed for a median of 9 months (4-17 months). Of these, 97 (30.5%) were started on CC+AZ therapy. These patients had higher baseline BMI and estradiol, which in multivariable regression were significant predictors for switching to CC+AZ therapy. A threshold of 18.5 pg/mL for baseline estradiol provided the highest accuracy for predicting the addition of AZ after adjusting for baseline BMI and total testosterone levels.

CONCLUSIONS

In our practice, following CC monotherapy, 30% of men were initiated on CC+AZ. Obesity (BMI≥30 kg/m²) and baseline estradiol ≥18.5 pg/mL can predict the conversion to combination therapy with addition of AZ. This information can be used to counsel patients and also help to identify patients who can be started on combination therapy upfront.

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.

The Role of Diet and Weight Loss in Improving Secondary Hypogonadism in Men with Obesity with or without Type 2 Diabetes Mellitus

Despite growing recognition of the issue, obesity represents one of the most common public health problems, and its rates are still increasing globally. Among the number of comorbidities and complications associated with obesity, hypogonadism is listed, and this disorder, although frequently neglected, is characterized by a relevant impact on both quality of life and life expectancy. It is generally accepted that hypogonadism secondary to obesity is functional since it is reversible following weight loss. This review summarizes all current research examining the bidirectional relationship between excess body weight and low testosterone levels. Specifically, it evaluates the role that diet, with or without physical activity, plays in improving body weight and hypogonadism in adult and elderly men with obesity, with or without type 2 diabetes mellitus.

Metabolic effects of dopamine agonists in patients with prolactinomas: a systematic review and meta-analysis

OBJECTIVES

Recent large cohort studies suggest an association between high plasma prolactin and cardiovascular mortality. The objective of this systematic review was to systematically assess the effect of reducing prolactin with dopamine agonist on established cardiovascular risk factors in patients with prolactinomas.

DESIGN

Bibliographical search was done until February 2019 searching the following databases: PubMed, EMBASE, WHO and LILAC. Eligible studies had to include participants with verified prolactinomas where metabolic variables were assessed before and after at least 2 weeks treatment with dopamine agonists.

METHODS

Baseline data and outcomes were independently collected by two investigators. The study was registered with PROSPERO (registration number CRD42016046525).

RESULTS

Fourteen observational studies enrolling 387 participants were included. The pooled standardized mean difference of the primary outcome revealed a reduction of BMI and weight of -0.21 (95% CI -0.37 to -0.05; P = 0.01; I2 = 71%), after treatment. Subgroup analysis suggested that the reduction of weight was primarily driven by studies with high prolactin levels at baseline (P = 0.04). Secondary outcomes suggested a small decrease in waist circumference, a small-to-moderate decrease in triglycerides, fasting glucose levels, HOMA-IR, HbA1c and hsCRP, and a moderate decrease in LDL, total cholesterol and insulin.

CONCLUSION

This systematic review suggests a reduction of weight as well as an improved lipid profile and glucose tolerance after treatment with dopamine agonist in patients with prolactinomas. These data are based on low-quality evidence.

Vascular Dysfunction among Malaysian Men with Increased BMI: An Indication of Synergistic Effect of Free Testosterone and Inflammation

Background and objectives: Obesity is associated with poor vascular function and may lead to future cardiovascular disease (CVD). Obesity is also related to increased inflammation and a low testosterone level. This study was conducted to determine the relationship between inflammation, testosterone level, and vascular function among subjects with an increased body mass index (BMI) and to determine whether both low testosterone and high inflammation have synergistic effects towards vascular dysfunction. Materials and Methods: A total of 303 men aged 40-80 years were recruited from Klang Valley, Malaysia. Their height, weight, blood pressure (BP), lipid, blood glucose level, total testosterone (TT), free testosterone (FT), and C-reactive protein (CRP) were measured. The carotid femoral pulse wave velocity (PWVCF) and augmentation index (AI) were also recorded as markers of vascular function. Results: The mean age of all the subjects was 54.46 ± 9.77 years. Subjects were divided into a low/normal body mass index (BMI) group (BMI < 25 kg/m2; NG, n = 154) and high BMI group (BMI ≥ 25 kg/m2; OG, n = 149). The mean BMI for NG was 22.20 ± 1.94 kg/m2 while for OG was 28.87 ± 3.24 kg/m2 (p < 0.01). The level of TT (OG = 21.13 ± 6.44 versus NG = 16.18 ± 6.16 nmol/L, p < 0.01) and FT (OG = 0.34 ± 0.12 versus NG = 0.39 ± 0.11 nmol/L, p < 0.01) were reduced while the level of CRP [OG = 1.05 (2.80) versus NG = 0.50 (1.50) mmol/L, p = 0.01] was increased in OG compared to NG. PWVCF (OG = 8.55 ± 1.34 versus NG = 8.52 ± 1.42 m/s, p = 0.02) and AI (OG = 16.91% ± 6.00% versus 15.88% ± 5.58%, p < 0.01) were significantly increased in OG after adjustment for other CVD risk factors. The subjects that had both a low FT and an increased CRP had higher AI when compared to those with a high CRP and high FT (p < 0.01). Conclusions: The increased BMI was associated with vascular dysfunction, mediated by a low testosterone level and increased inflammation. Furthermore, having both conditions concurrently lead to higher vascular dysfunction. Weight loss, testosterone supplementation, and the anti-inflammatory agent may be beneficial for men to prevent vascular dysfunction.

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.

Male Obesity-related Secondary Hypogonadism - Pathophysiology, Clinical Implications and Management

The single most significant risk factor for testosterone deficiency in men is obesity. The pathophysiological mechanisms involved in male obesity-related secondary hypogonadism are highly complex. Obesity-induced increase in levels of leptin, insulin, proinflammatory cytokines and oestrogen can cause a functional hypogonadotrophic hypogonadism with the defect present at the level of the hypothalamic gonadotrophin-releasing hormone (GnRH) neurons. The resulting hypogonadism by itself can worsen obesity, creating a self-perpetuating cycle. Obesity-induced hypogonadism is reversible with substantial weight loss. Lifestyle-measures form the cornerstone of management as they can potentially improve androgen deficiency symptoms irrespective of their effect on testosterone levels. In selected patients, bariatric surgery can reverse the obesity-induced hypogonadism. If these measures fail to relieve symptoms and to normalise testosterone levels, in appropriately selected men, testosterone replacement therapy could be started. Aromatase inhibitors and selective oestrogen receptor modulators are not recommended due to lack of consistent clinical trial-based evidence.

Effects of SHBG rs1799941 Polymorphism on Free Testosterone Levels and Hypogonadism Risk in Young Non-Diabetic Obese Males

Introduction: Obesity has been associated with increased risk of presenting hypogonadism. Free testosterone (FT) is the fraction of testosterone that carries out the biological function of testosterone, and is determined from total testosterone (TT) and sex-hormone binding globulin (SHBG) levels. We aimed to study the SHBG polymorphism rs1799941 in a cohort of young non-diabetic obese males to unravel the possible implication of this polymorphism in obesity-related hypogonadism. Methodology: 212 young (<45 years) non-diabetic obese (BMI ≥ 30 kg/m²) males participated in this study. Subjects were classified according to TT and FT levels in: Eugonadal (n = 55, TT > 3.5 ng/mL and FT ≥ 70 pg/mL; EuG), normal FT hypogonadism (n = 40, TT < 3.5 and FT ≥ 70 pg/mL; normal FT HG) and hypogonadism (n = 117, TT < 3.5 ng/mL and TL < 70 pg/mL; HG). The SHBG rs1799941 polymorphism (GG/GA/AA) was analyzed using the Taqman Open Array (Applied biosystem). Results: The rs1799941 frequencies were different among the groups. Higher proportion of the allele (A) was found in HG, compared to EuG and normal FT HG. Among the genotypes, the rare homozygous (AA) were found in the normal FT HG group and higher levels of serum SHBG and lower of FT were observed. The presence of the allele A was related (according to lineal regression models) to an increased of SHBG levels ((GA) β = 3.28; (AA) β = 12.45) and a decreased of FT levels ((GA) β = −9.19; (AA) β = −18.52). The presence of the allele (A) increased the risk of presenting HG compared to normal FT HG (OR = 2.54). Conclusions: The rs1799941 of the SHBG gene can partially determine the presence of obesity-related hypogonadism in young non-diabetic males and whether these subjects have normal FT HG.

Dietary patterns in relation to testosterone levels and severity of impaired kidney function among middle-aged and elderly men in Taiwan: a cross-sectional study

Background

Chronic Kidney Disease (CKD), characterized by an impaired kidney function, is associated with low testosterone levels. This study investigated the association between dietary patterns, testosterone levels, and severity of impaired kidney function among middle-aged and elderly men.

Methods

This cross-sectional study used the database from a private health-screening institute in Taiwan between 2008 and 2010. Men aged 40 years old and older (n = 21,376) with estimated glomerular filtration rate (eGFR) < 90 mL/min/1.73 m² and proteinuria were selected. Among 21,376 men, 256 men had available measurements of testosterone levels. Dietary assessment was conducted using a food frequency questionnaire and three dietary patterns (fried-processed, vege-seafood, and dairy-grain dietary patterns) were identified using principal component analysis.

Results

Men in the lower tertiles (T1 and T2) of eGFR had significantly decreased testosterone levels by 0.8 (95% CI: − 1.40, − 0.20) and 0.9 nmol/L (95% CI: − 1.43, − 0.33). Furthermore, serum triglycerides (TG) levels were inversely associated with testosterone levels (β = − 0.51, 95% CI: − 0.77, − 0.24). Men in the higher tertile of fried-processed dietary pattern scores were associated with decreased testosterone levels by 0.8 nmol/L (95% CI: − 1.40, − 0.16), reduced testosterone-to-TG (T/TG) ratio by 1.8 units (95% CI: − 2.99, − 0.53), and increased risk of moderate/severe impaired kidney function (eGFR < 60 mL/min/1.73 m²) and proteinuria severity by 1.35 (95% CI: 1.15, 1.58) and 1.18 (95% CI: 1.02, 1.37) times respectively. In contrast, the vege-seafood dietary pattern was negatively associated with severity of impaired kidney function and proteinuria after multivariable adjustment, but had no association with testosterone levels and T/TG ratio.

Conclusions

The fried-processed dietary pattern is negatively associated with testosterone levels but positively associated with the severity of impaired kidney function. However, the vege-seafood and dairy-grain dietary patterns appear to have beneficial effects.

Electronic supplementary material

The online version of this article (10.1186/s12937-019-0467-x) contains supplementary material, which is available to authorized users.

Reversible male hypogonadotropic hypogonadism due to energy deficit

CONTEXT

Calorie restriction and overtraining are increasingly seen in young men who suffer from increasing societal pressure to attain a perceived ideal male body image. The resulting energy deficit can lead to multiple endocrine consequences, including suppression of the male gonadal axis.

DESIGN

We reviewed the literature, including two unpublished cases.

RESULTS

We identified 23 cases, aged median (range) 20 years (16-33), with a body mass index of 15.9 kg/m² (12.5-20.5). Total testosterone was 3.0 nmol/L (0.6-21.3), and luteinizing hormone (LH) 1.2 mIU/L (<0.2-7.5), with 91% of cases demonstrating hypogonadotropic hypogonadism. Associated findings included evidence of growth hormone resistance (increased growth hormone in 57% and low insulin-like growth factor-1 in 71%), hypercortisolaemia (50%) and a nonthyroidal illness picture (67%). In cases with longitudinal measurements following weight regain, serum testosterone (n = 14) increased from median [interquartile range] 3.2 nmol/L [1.9-5.1] to 14.3 nmol/L [9.3-21.2] (P < 0.001), and LH (n = 8) from 1.2 IU/L [0.8-1.8] to 3.5 IU/L [3.3-4.3] (P = 0.008).

CONCLUSIONS

Hypogonadotropic hypogonadism can occur in the context of energy deprivation in young otherwise healthy men and may be underrecognized. The evidence suggests that gonadal axis suppression and associated hormonal abnormalities represent an adaptive response to increased physiological stress and total body energy deficit. The pathophysiology likely involves hypothalamic suppression due to dysregulation of leptin, ghrelin and pro-inflammatory cytokines. The gonadal axis suppression is functional, because it can be reversible with weight gain. Treatment should focus on reversing the existing energy deficit to achieve a healthy body weight, including psychiatric input where required.

An update on heart disease risk associated with testosterone boosting medications

INTRODUCTION

The cardiovascular (CV) safety of testosterone replacement therapy (TRT) remains a crucial issue in the management of subjects with late-onset hypogonadism. The authors systematically reviewed and discussed the available evidence focusing our analysis on heart-related issues.

AREAS COVERED

All the available data from prospective observational studies evaluating the role endogenous T levels on the risk of acute myocardial infarction (AMI) were collected and analyzed. In addition, the impact of TRT on heart-related diseases, as derived from pharmaco-epidemiological studies as well as from randomized placebo-controlled trials (RCTs), was also investigated.

EXPERT OPINION

Available evidence indicates that endogenous low T represents a risk factor of AMI incidence and its related mortality. TRT in hypogonadal patients is able to improve angina symptoms in subjects with ischemic heart diseases and exercise ability in patients with heart failure (HF). In addition, when prescribed according to the recommended dosage, TRT does not increase the risk of heart-related events.

Impact of Metabolically Healthy Obesity in Patients with Andrological Problems

BACKGROUND

Although the pathogenic role of metabolically complicated obesity (MCO) in erectile dysfunction (ED), major adverse cardiovascular events (MACE), and male infertility has been widely studied, that of metabolically healthy obesity (MHO) has been poorly investigated.

AIM

To assess the role of MHO in the pathogenesis of ED, prediction of MACE, and male reproductive health.

METHODS

A consecutive series of 4,945 men (mean age, 50.5 ± 13.5 years) with sexual dysfunction (SD) (cohort 1) and 231 male partners of infertile couples (mean age, 37.9 ± 9.1 years; cohort 2) were studied. A subset of men with SD (n = 1,687) was longitudinally investigated to evaluate MACE. All patients underwent clinical, biochemical, erectile function, and flaccid penile color Doppler ultrasound (PCDU) assessment. Infertile men also underwent scrotal and transrectal ultrasound; semen analysis, including interleukin (IL-) 8; and prostatitis-like symptom assessment. MHO was defined as body mass index >30 kg/m² with high-density lipoprotein cholesterol level >40 mg/dL and absence of diabetes or hypertension. The rest of the obesity sample was defined as MCO. MHO or MCO were compared with the rest of the sample, defined as normal weight (NW) individuals.

OUTCOMES

Clinical, biochemical, erectile, and PCDU assessment in MHO, MCO and NW men in both cohorts; longitudinal MACE incidence assessment in cohort 1.

RESULTS

In cohort 1, 816 men (16.5%) were obese, 181 (3.7%) were MHO, and 635 (12.8%) were MCO. In cohort 2, 68 men (28.4%) were obese, 19 (8.2%) were MHO, and 49 (21.2%) were MCO. After adjusting for confounders, in both samples, the men with MHO and MCO had lower total testosterone levels and worse PCDU parameters compared with the NW men. However, only MCO men had worse erectile function compared with NW men. In the longitudinal study, both MHO and MCO men independently had a higher incidence of MACE compared with NW men (P < .05 for both). In cohort 2, MHO and MCO men had a larger prostate volume, and MCO men also had higher ultrasound and biochemical (IL-8) features of prostatic inflammation compared with NW men, but no differences in prostatitis-like symptoms or seminal parameters.

CLINICAL IMPLICATIONS

MHO men should be considered at high cardiovascular risk like MCO men and followed-up for erectile dysfunction and prostate abnormalities overtime.

STRENGTHS & LIMITATIONS

The study simultaneously examined several endpoints with validated instruments within 2 different male populations, 1 with SD and 1 with infertility. As for limitations, there is no consensus in the scientific community regarding the definition of MHO, and the results are derived from patients with SD or infertility, which could have different characteristics than the general male population.

CONCLUSION

MHO is associated with subclinical ED, increased cardiovascular risk, and prostate enlargement. Lotti F, Rastrelli G, Maseroli E, et al. Impact of Metabolically Healthy Obesity in Patients with Andrological Problems. J Sex Med 2019:16;821-832.

Management of Anabolic Steroid-Induced Infertility: Novel Strategies for Fertility Maintenance and Recovery

There is often inherent conflict in the overlapping fields of male fertility and andrology. While the goal of all male fertility specialists is to facilitate and preserve biologic paternity, many practitioners also care for a significant number of patients suffering from hypogonadism. Exogenous testosterone administration, the gold standard for the management of these patients, almost universally impairs spermatogenesis and can even completely eradicate it in some men. With steady increases in both the incidence of hypogonadism and average paternal age, practitioners are now encountering hypogonadal men who desire future fertility or men suffering the effects of earlier androgenic anabolic steroid use with increasing frequency. In this manuscript, we review management strategies for these complex patients and explore novel medications that may be of use in this population.

Assessment of Gender-Affirming Hormone Therapy Requirements

PURPOSE

There are currently no recommendations regarding the starting doses of hormone therapy for individuals with gender dysphoria. The purpose of this study was to assess the hormone dose needed to achieve target hormone levels in transgender men and transgender women, and whether body mass index (BMI) affects these doses.

METHODS

A retrospective chart review of subjects seeking gender-affirming hormone therapy was performed. Height, weight, hormone doses, and serum hormone levels were collected from charts. Data were analyzed for a correlation between BMI and effective hormone dosing (dose that achieved hormone levels in the target range).

RESULTS

Charts from 319 subjects were reviewed; however, only 84 transgender women and 71 transgender men had serum hormone levels available and only 40 transgender women and 54 transgender men had plasma hormone levels in the target range (normal range for affirmed gender). For transgender women, there was a significant negative correlation between BMI and effective estradiol dose (r = -0.337, p = 0.04). For transgender men, there was a positive correlation between BMI and effective testosterone dose (r = 0.409, p = 0.002).

CONCLUSION

Increased BMI was associated with lower estrogen dose requirements in transgender women. In transgender men, an increase in BMI was associated with increased testosterone dose requirements. These results suggest that BMI may influence effective gender-affirming hormone dosing; however, further studies are needed to examine its utility in determining the initial hormone dose.

A body shape index (ABSI) reflects body composition changes in response to testosterone treatment in obese men

BACKGROUND

Interventions such as testosterone treatment may change body composition and metabolic outcomes without substantial changes in weight and BMI.

OBJECTIVES

Using testosterone treatment as a paradigm, we hypothesized that a body shape index (ABSI) reflects body composition changes more accurately than traditional markers, such as weight, BMI and waist circumference.

INTERVENTION

Secondary analysis of a 56-week RCT in 100 dieting obese men with low-normal testosterone receiving testosterone treatment or placebo, and subsequent off-treatment follow-up.

RESULTS

At the end of the trial period, ABSI-unlike weight, BMI or waist circumference-had significantly decreased in the treatment group, compared with placebo (mean adjusted difference -0.18 [95% CI: -0.32, -0.05] × 10^-2 m^11/6kg^-2/3, overall P<0.001). Changes in ABSI during the active trial phase correlated with changes in fat mass (tau = 0.18, P = 0.02), and not with lean mass (tau = -0.11, P = 0.14), BMI (tau = 0.10, P = 0.17), or visceral fat (tau = 0.07, P = 0.37). ABSI baseline values were positively correlated with waist circumference (tau = 0.21, P = 0.002) and visceral fat (tau = 0.18, P = 0.009), correlated inversely with lean mass (tau = -0.21, P = 0.002), and were uncorrelated with BMI (tau = -0.10, P = 0.15) and fat mass (tau = 0.01, P = 0.83). Two years after cessation of treatment, ABSI again reflected body composition as the between-group differences in all parameters did not persist.

CONCLUSIONS

A readily obtainable anthropomorphic measure, ABSI reflects the differential loss of fat mass mediated by testosterone in dieting obese men more closely than BMI or waist circumference. It may serve as a clinically useful marker to monitor body composition changes, particularly in response to interventions.

Clinical practice update on testosterone therapy for male hypogonadism: Contrasting perspectives to optimize care

US Endocrine Society (ES) published a clinical practice guideline on testosterone therapy in men with hypogonadism, and Endocrine Society of Australia (ESA) a position statement on management of male hypogonadism. Both emphasize the importance of diagnosing men who are androgen deficient due to organic (classical or pathological) hypogonadism arising from disorders of the hypothalamus, pituitary or testes, who assuredly benefit from testosterone therapy. Both recognize that men with an intact gonadal axis may have low testosterone concentrations, for instance older men or men with obesity or other medical comorbidities. ES guidelines classify such symptomatic men as having organic (advanced age) or functional (obesity, medical comorbidities) hypogonadism, giving an option for testosterone therapy as a shared decision between clinicians and individual patients. ESA did not recommend testosterone therapy in these men. ES offers a reference range for total testosterone established in young men, while ESA cites age-standardized reference ranges. ES recommends using free testosterone as well as total testosterone to identify men with hypogonadism in conditions where sex hormone-binding globulin (SHBG) is altered, or when total testosterone is borderline. ESA recommends confirmatory biochemical testing with total testosterone, recognizing that this may be lower than expected if SHBG concentrations are low. Both emphasize the importance of identifying pre-existing prostate and cardiovascular disease prior to initiating testosterone therapy, with ES providing specific recommendations for PSA measurement, deferring testosterone therapy after major cardiovascular events and indications for pituitary imaging. These contrasting approaches highlight gaps in the evidence base where individualized patient management is required.

Testosterone-Associated Dietary Pattern Predicts Low Testosterone Levels and Hypogonadism

Obesity and low serum testosterone (T) levels are interrelated and strongly influenced by dietary factors, and their alteration entails a great risk of hypogonadism. Substantial evidence suggests a bidirectional relationship between nutrient metabolism (e.g., glucose, lipids, and iron) and T levels in men; however, T-related dietary patterns remain unclear. This study investigated the dietary patterns associated with serum total T levels and its predictive effect on hypogonadism and the body composition. Anthropometry, blood biochemistry, and food frequency questionnaires were collected for 125 adult men. Dietary patterns were derived using a reduced rank regression from 32 food groups. Overall prevalence rates of central obesity and hypogonadism were 48.0% and 15.7%, respectively. An adjusted linear regression showed that age, insulin, red blood cell (RBC) aggregation, and transferrin saturation independently predicted serum total T levels (all p < 0.01). The total T-related dietary pattern (a high consumption of bread and pastries, dairy products, and desserts, eating out, and a low intake of homemade foods, noodles, and dark green vegetables) independently predicted hypogonadism (odds ratio: 5.72; 95% confidence interval: 1.11‒29.51, p < 0.05) for those with the highest dietary pattern scores (Q4) compared to those with the lowest (Q1). Scores were also negatively correlated with the skeletal muscle mass (p for trend = 0.002) but positively correlated with the total body fat mass (p for trend = 0.002), visceral fat mass (p for trend = 0.001), and to a lesser extent, subcutaneous fat mass (p for trend = 0.035) after adjusting for age. Randomized controlled trials are needed to confirm that improvement in dietary pattern can improve T levels and reduce hypogonadism.