Impact of Metabolic Syndrome Factors on Testosterone and SHBG in Type 2 Diabetes Mellitus and Metabolic Syndrome

Gonadal hormones and metabolic syndrome in middle-aged and elderly males: results from a prospective cohort study in China

Background

Research has shown that gonadal hormones are involved in metabolic pathways relevant to metabolic syndrome (MetS). Nevertheless, no longitudinal study has been conducted on the association between SHBG and MetS in Chinese. The objective of our study was to determine whether there is any association between middle-aged and elderly males in China.

Methods

A total of 531 eligible male subjects, aged above 40 years or older, without MetS at baseline, were recruited. Sex hormone binding globulin (SHBG), total testosterone (TT), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were measured. A harmonized definition and recommended thresholds for the Chinese population were used to determine metabolic syndrome.

Results

During 3.2 years of follow-up, 20.7% of subjects had developed MetS. Compared with the non-MetS group, subjects in the new-onset MetS group had significantly lower SHBG (43.5 nmol/L [28.8, 74.9] vs 53.7nmol/L [33.8, 115.0], P=0.0018), TT (18.1nmol/L [13.6-21.7] vs 19.5nmol/L[15.0-23.6], P=0.0204), and LH (5.13mIU/L [3.63-7.29] vs 5.87mIU/L [4.05-8.36]) at baseline. The incidence of MetS was decreased according to elevated SHBG quartiles (Q1:26.9%, Q2:22.7%, Q3:21.1%, Q4:12.1%, P for trend =0.0035), TT (Q1: 25.2%, Q2:23.7%, Q3: 17.3%, Q4: 16.7%, P for trend=0.0425), and LH (Q1:25.0%, Q2:21.8%, Q3: 21.8%, Q4: 14.3%, P for trend=0.0411). Compared with those in quartile 4, the OR[CI] of incident MetS for participants in Quartile 1 was 2.33[1.13-4.79] after multiple adjustments. But associations between incident MetS and different quartiles of LH, TT, and FSH were not observed after multiple adjustments. In the subgroup analyses, the significant association between SHBG level and Mets was detected in subjects over 60 years or older, with normal BMI, without insulin resistance, and with eGFR ≥90 mL/min per 1.73m2.

Conclusion

Compared with TT, LH, and FSH, a lower level of SHBG is significantly related to the incidence of MetS among middle-aged and elderly males in China.

Gaps in the management of diabetes in Asia: A need for improved awareness and strategies in men's sexual health

Sexual dysfunction, which is defined as 'difficulty during any stage of the sexual encounter that prevents or impairs the individual or couple from enjoying sexual activity', is globally prevalent in males with prediabetes and diabetes. It is an early harbinger of cardiovascular diseases and has a profound impact on one's physical, mental, and social health. Among patients with either prediabetes or diabetes, the most common male sexual dysfunctions are hypogonadism, erectile dysfunction, and premature ejaculation. In Asia, although sexual health is an important factor of men's health, it is rarely discussed freely in real-life practice. Addressing sexual health in Asian males has always been challenging with multiple barriers at the levels of patients and health care providers. Therefore, the assessment and management of sexual dysfunction in routine clinical practice should involve a holistic approach with effective patient-provider communication. In this review, we discuss the epidemiology, pathophysiology, and the management of hypogonadism, erectile dysfunction, and premature ejaculation among males with either prediabetes or diabetes (type 1 and type 2), as well as the evidence gaps across Asia.

Associations between blood and urinary manganese with metabolic syndrome and its components: Cross-sectional analysis of National Health and Nutrition Examination Survey 2011-2016

Manganese (Mn) may improve cardiometabolic health with its anti-oxidative ability. However, epidemiological evidence on the overall and sex-specific relationship between Mn exposure and metabolic syndrome (MetS) has been inconclusive. We evaluated the associations of urinary (n = 1713) and blood (n = 3335) Mn levels with the prevalence of MetS, its components (elevated waist circumference, impaired glucose metabolism, elevated blood pressure and dyslipidemia) and sex-dependent heterogeneities among participants in the United States National Health and Nutrition Examination Survey 2011-2016. After adjusting for multiple covariates and the levels of other metals (Arsenic, Barium, Cadmium, Mercury, Molybdenum, Tin and Uranium), urinary Mn at the third quartile associated with a lower odd of MetS (odds ratio [OR] = 0.55, 95% confidence interval [C.I.] = 0.32-0.97), elevated waist circumference (OR = 0.56, 95% C.I. = 0.36-0.86) and elevated fasting plasma glucose (OR = 0.46, 95% C.I. = 0.27-0.76) among overall participants, and lower odds of MetS (OR = 0.40, 95% C.I. = 0.16-0.99), elevated waist circumference (OR = 0.39, 95% C.I. = 0.19-0.81) and elevated fasting plasma glucose (OR = 0.44, 95% C.I. = 0.22-0.90) among men. The U-shaped dose-response relationship between urinary Mn and MetS (P non-linear = 0.008) was observed among all participants. We did not observe the significant associations of blood Mn with the prevalence of MetS. Compared with other metals, urinary Mn played a less important role in development of MetS (posterior inclusion probabilities [PIP] = 0.49 for Mn versus 0.54 to 0.91 for other metals), but the contribution of blood Mn (PIP = 0.59 versus 0.60 to 0.61) was similar to other blood metals (Cadmium, Lead, Mercury and Selenium). These findings have provided new evidence of the potential roles of Mn in cardiometabolic health, and the needs to explore how Mn interacts with multiple metals in sex-specific manner.

Impact of triglycerides and waist circumference on insulin resistance and β-cell function in non-diabetic first-degree relatives of type 2 diabetes

BACKGROUND

Although there is abundant evidence indicating the relative contribution of insulin resistance (HOMA-IR) and β-cell dysfunction (HOMA-β) among first-degree relatives (FDRs) of Type 2 DM patients, few studies reported the association between HOMA-IR and HOMA-β with metabolic syndrome. Our objective was to evaluate the impact of metabolic syndrome factors on HOMA-IR, HOMA-β and glycoproteins in non-diabetic FDRs.

METHODS

In this study, 103 Yemeni male subjects aged 25-42 years, with BMI < 25 kg/m² were examined, 39 of whom were normal subjects with no family history of diabetes served as control and 64 subjects were non-diabetic FDRs of Type 2 DM patients.

RESULTS

Both glycoproteins, glycated haemoglobin (HbA1c) and fructosamine as well as insulin, HOMA-IR and HOMA-β were significantly (p = 4.9 × 10^-9; 6.0 × 10^-8; 6.6 × 10^-12; 1.3 × 10^-7; 5.5 × 10^-12, respectively) higher in non-diabetic FDRs as compared to control group. Fasting plasma glucose, though within normal range, were significantly (p = 0.026) higher in non-diabetic FDRs. Linear regression analysis showed that both TG and WC are the main metabolic syndrome factors that significantly increased HOMA-IR (B = 0.334, p = 1.97 × 10^-6; B = 0.024, p = 1.05 × 10^-5), HOMA-β (B = 16.8, p = 6.8 × 10^-5; B = 0.95, p = 0.004), insulin (B = 16.5, p = 1.2 × 10^-6; B = 1.19, p = 8.3 × 10^-6) and HbA1c (B = 0.001, p = 0.034; B = 0.007, p = 0.037).

CONCLUSION

Triglyceride and WC are the important metabolic syndrome factors associated with insulin resistance, basal β-cell function and insulin levels in non-diabetic FDR men of Type 2 DM patients. Moreover, FDRs showed insulin resistance with compensatory β-cell function (hyperinsulinaemia) suggesting that insulin resistance precede the development of pancreatic β-cell dysfunction in individuals at risk of Type 2 DM.

Aquatic Exercise Positively Affects Physiological Frailty among Postmenopausal Women: A Randomized Controlled Clinical Trial

Frailty is a risk factor associated with aging. Physical exercise is an important lifestyle factor that can help to avoid risks associated with aging. Therefore, we aimed to determine the effects of aquatic exercise for 12 weeks on body composition, cardiovascular disease risk factors, insulin resistance, and aging-related sex hormones in elderly South Korean women. Twenty-two women aged 70–82 years were randomly assigned to groups that participated or did not participate (controls; n = 10 in aquatic exercise for 60 min, three times per week for 12 weeks (n = 12). Exercise intensity defined as the rating of perceived exertion (RPE), was increased from 12–13 to 13–14, and to 14–15 during weeks 1–4, 5–8, and 9–12, respectively. Body composition (skeletal muscle mass, ratio (%) body fat, and waist circumference), cardiovascular disease risk factors (total, high-density lipoprotein, and low-density lipoprotein cholesterol), insulin resistance (glucose, insulin, and homeostatic model assessment of insulin resistance [HOMA-IR]), and aging-related sex hormone changes (dehydroepiandrosterone-sulfate [DHEA-S]) and sex hormone-binding globulin [SHBG]) were assessed. Aquatic exercise safely improved body composition, reduced insulin resistance, and positively affected the sex hormones DHEA-S and SHBG as well as blood lipid profiles. Our findings suggested that the aquatic exercise program positively altered blood lipids, regulated glucose levels, and sex hormone levels. Therefore, regular, and continuous aquatic exercise is recommended to prevent frailty, decrease cardiovascular risk, and provide older women with an optimal quality of life as they age.

Race, Socioeconomic Status, and Sex Hormones among Male and Female American Adolescents

Although early sexual initiation and childbearing are major barriers against the upward social mobility of American adolescents, particularly those who belong to a low socioeconomic status (SES) and racial minorities such as Blacks, less is known on how SES and race correlate with adolescents' sex hormones. An understanding of the associations between race and SES with adolescents' sex hormones may help better understand why racial, and SES gaps exist in sexual risk behaviors and teen pregnancies. To extend the existing knowledge on social patterning of adolescents' sex hormones, in the current study, we studied social patterning of sex hormones in a national sample of male and female American adolescents, with a particular interest in the role of race and SES. For this cross-sectional study, data came from the baseline data (wave 1) of the Adolescent Brain Cognitive Development (ABCD) study, a national longitudinal prospective study of American adolescents. This analysis included 717 male and 576 female non-Hispanic White or Black adolescents ages 9-10. The dependent variables were sex hormones (testosterone for males and estradiol for females). Independent variables were age, race, family marital status, parental education, and financial difficulties. For data analysis, linear regression models were used. Age, race, parental education, and financial difficulties were associated with estradiol in female and testosterone levels in male adolescents. Associations were not identical for males and females, but the patterns were mainly similar. Low SES explained why race is associated with higher estradiol in female adolescents. Marital status of the family did not correlate with any of the sex hormones. Being Black and low SES were associated with a higher level of sex hormones in male and female adolescents. This information may help us understand the social patterning of sexual initiation and childbearing. Addressing racial and economic inequalities in early puberty, sexual initiation, and childbearing is an essential part of closing the racial and economic gaps in the US.

Men with Latent Autoimmune Diabetes and Type 2 Diabetes May Have Different Change Patterns in Free Testosterone

Objective

Type 2 diabetic (T2D) male patients with low total testosterone (TT) levels are at an increasing risk of all-cause mortality. However, the levels of TT in male patients with latent autoimmune diabetes in adults (LADA) remain largely unknown. Research Design and Methods. This was a single-center, open, observational study. The inclusion criteria were male patients who were diagnosed with LADA, and sex, body mass index, C-peptide, and glycated hemoglobin (HbA1c) levels matched with those of T2D patients. Islet function/sensitivity and sex hormone concentrations were determined at baseline and 1-year follow-up. The primary endpoint was the changes in androgen levels from baseline to 1-year follow-up in patients with LADA.

Results

Our data showed that TT and Bio-T levels remained unchanged, while FT levels significantly decreased from baseline to 1-year follow-up in patients with T2D. However, TT, Bio-T, and FT concentrations dramatically increased in the LADA group from baseline to 1-year follow-up. Furthermore, a Spearman analysis showed that changes of TT, FT, and Bio-T levels from baseline to endpoint were significantly negatively correlated with Δ homeostasis model assessment-2 IR (ΔHOMA2-IR), respectively.

Conclusions

The FT change patterns in patients with LADA may differ from those in patients with T2D. Our data also indicated the significant negative correlation between insulin sensitivity and changes of TT, FT, and Bio-T levels along with the diabetic duration in patients with T2D and LADA.

SHBG levels in primary infertile men: a critical interpretation in clinical practice

OBJECTIVE

We aimed to test the association between age, BMI and sex-hormone-binding globulin (SHBG) in a homogenous cohort of white-European men presenting for primary couple's infertility.

DESIGN

Retrospective study.

METHODS

Data from 1547 infertile men were analysed. Health-significant comorbidities were scored with the Charlson comorbidity index (CCI). Fasting serum hormones were measured in every patient. Age was considered according to quartile groups (<33, 33-41, >41 years) and BMI as normal weight (18.5-24.9 kg/m2), overweight (25.0-29.9 kg/m2) and obesity (>30 kg/m2). Descriptive statistics and linear regression analysis tested the associations between age, BMI and SHBG.

RESULTS

Median SHBG levels increased across quartiles of age and decreased along with BMI increases (all P < 0.001). For each year increase in age, SHBG increased 0.32 nmol/L; conversely, for each unit increase in BMI, SHBG decreased by 1.1 nmol/L (all P < 0.001). SHBG levels decline with increasing BMI was greater than SHBG progressive increase with age. Overall, BMI explained 3.0 times more of the variability in SHBG than did ageing. At multivariate linear model, age and BMI were the most significant factors influencing SHBG concentration (all P < 0.001), after accounting for CCI, albumin levels and smoking status.

CONCLUSIONS

We found a wide distribution of SHBG concentrations across age and BMI values in primary infertile men. The association between BMI and lowered SHBG levels seems to be greater than the association of ageing with increased SHBG.

Testosterone concentrations and risk of cardiovascular events in androgen-deficient men with atherosclerotic cardiovascular disease

BACKGROUND

Whether androgen deficiency among men increases the risk of cardiovascular (CV) events or is merely a disease marker remains a subject of intense scientific interest.

OBJECTIVES

Among male subjects in the AIM-HIGH Trial with metabolic syndrome and low baseline levels of high-density lipoprotein (HDL)-cholesterol who were randomized to niacin or placebo plus simvastatin, we examined the relationship between low baseline testosterone (T) concentrations and subsequent CV outcomes during a mean 3-year follow-up.

METHODS

In this post hoc analysis of men with available baseline plasma T concentrations, we examined the relationship between clinical/demographic characteristics and T concentrations both as a continuous and dichotomous variable (<300 ng/dL ["low T"] vs. ≥300 ng/dL ["normal T"]) on rates of pre-specified CV outcomes, using Cox proportional hazards models.

RESULTS

Among 2118 male participants in whom T concentrations were measured, 643 (30%) had low T and 1475 had normal T concentrations at baseline. The low T group had higher rates of diabetes mellitus, hypertension, elevated body mass index, metabolic syndrome, higher blood glucose, hemoglobin A1c, and triglyceride levels, but lower levels of both low-density lipoprotein and HDL-cholesterol, and a lower rate of prior myocardial infarction (MI). Men with low T had a higher risk of the primary composite outcome of coronary heart disease (CHD) death, MI, stroke, hospitalization for acute coronary syndrome, or coronary or cerebral revascularization (20.1%) compared with the normal T group (15.2%); final adjusted HR 1.23, P = .07, and a higher risk of the CHD death, MI, and stroke composite endpoint (11.8% vs. 8.2%; final adjusted HR 1.37, P = .04), respectively.

CONCLUSIONS

In this post hoc analysis, there was an association between low baseline testosterone concentrations and increased risk of subsequent CV events in androgen-deficient men with established CV disease and metabolic syndrome, particularly for the composite secondary endpoint of CHD death, MI, and stroke.

CONDENSED ABSTRACT

In this AIM-HIGH Trial post hoc analysis of 2118 men with metabolic syndrome and low HDL-cholesterol with available baseline plasma testosterone (T) samples, 643 males (30%) had low T (mean: 229 ng/dL) and 1475 (70%) had normal T (mean: 444 ng/dL) concentrations. The "low T" group had a 24% higher risk of the primary 5-component endpoint (20.1%) compared with the normal T group (15.2%); final adjusted HR 1.23, P = .07). There was also a 31% higher risk of the secondary composite endpoint: coronary heart disease death, myocardial infarction, and stroke (11.8% vs. 8.2%, final adjusted HR 1.37, P = .04) in the low vs. normal T group, respectively.

The Effects of Androgens on Cardiometabolic Syndrome: Current Therapeutic Concepts

INTRODUCTION

Cardiometabolic syndrome (CMS), as a bunch of metabolic disorders mainly characterized by type 2 diabetes mellitus (T2DM), hypertension, atherosclerosis, central adiposity, and abdominal obesity triggering androgen deficiency, is one of the most critical threats to men. Although many significant preclinical and clinical findings explain CMS, new approaches toward common pathophysiological mechanisms and reasonable therapeutic targets are lacking.

AIM

To gain a further understanding of the role of androgen levels in various facets of CMS such as the constellation of cardiometabolic risk factors including central adiposity, dyslipidemia, insulin resistance, diabetes, and arterial hypertension and to define future directions for development of effective therapeutic modalities.

METHODS

Clinical and experimental data were searched through scientific literature databases (PubMed) from 2009 to October 2019.

MAIN OUTCOME MEASURE

Evidence from basic and clinical research was gathered with regard to the causal impact and therapeutic roles of androgens on CMS.

RESULTS

There are important mechanisms implicated in androgen levels and the risk of CMS. Low testosterone levels have many signs and symptoms on cardiometabolic and glycometabolic risks as well as abdominal obesity in men.

CLINICAL IMPLICATIONS

The implications of the findings can shed light on future improvements in androgen levels and add potentially predictive risk for CMS, as well as T2DM, abdominal obesity to guide clinical management in the early stage.

STRENGTHS & LIMITATIONS

This comprehensive review refers to the association between androgens and cardiovascular health. A limitation of this study is the lack of large, prospective population-based studies that analyze the effects of testosterone treatment on CMS or mortality.

CONCLUSION

Low testosterone levels have several common features with metabolic syndrome. Thus, testosterone may have preventive role in the progress of metabolic syndrome and subsequent T2DM, abdominal obesity, and cardiovascular disease and likely affect aging men's health mainly through endocrine and vascular mechanisms. Further studies are necessary to evaluate the therapeutic interventions directed at preventing CMS in men. Kirlangic OF, Yilmaz-Oral D, Kaya-Sezginer E, et al. The Effects of Androgens on Cardiometabolic Syndrome: Current Therapeutic Concepts. Sex Med 2020;8:132-155.

Androgen-Regulated Cardiac Metabolism in Aging Men

The prevalence of cardiovascular mortality is higher in men than in age-matched premenopausal women. Gender differences are linked to circulating sex-related steroid hormone levels and their cardio-specific actions, which are critical factors involved in the prevalence and features of age-associated cardiovascular disease. In women, estrogens have been described as cardioprotective agents, while in men, testosterone is the main sex steroid hormone. The effects of testosterone as a metabolic regulator and cardioprotective agent in aging men are poorly understood. With advancing age, testosterone levels gradually decrease in men, an effect associated with increasing fat mass, decrease in lean body mass, dyslipidemia, insulin resistance and adjustment in energy substrate metabolism. Aging is associated with a decline in metabolism, characterized by modifications in cardiac function, excitation-contraction coupling, and lower efficacy to generate energy. Testosterone deficiency -as found in elderly men- rapidly becomes an epidemic condition, associated with prominent cardiometabolic disorders. Therefore, it is highly probable that senior men showing low testosterone levels will display symptoms of androgen deficiency, presenting an unfavorable metabolic profile and increased cardiovascular risk. Moreover, recent reports establish that testosterone replacement improves cardiomyocyte bioenergetics, increases glucose metabolism and reduces insulin resistance in elderly men. Thus, testosterone-related metabolic signaling and gene expression may constitute relevant therapeutic target for preventing, or treating, age- and gender-related cardiometabolic diseases in men. Here, we will discuss the impact of current evidence showing how cardiac metabolism is regulated by androgen levels in aging men.

Association of high circulating testosterone with increased glycaemic variability in type 2 diabetes: A cross-sectional study in China

BACKGROUND

Testosterone affects insulin resistance, but the effect of testosterone treatment on type 2 diabetes (T2D) remains controversial. We aimed to investigate the association between circulating total testosterone (TT) and glycaemic variability using continuous glucose monitoring (CGM) in patients with T2D.

METHODS

A total of 248 men with T2D were enrolled in the study. Clinical characteristics and plasma for glycated haemoglobin (HbA1c) and C-peptide assessment were collected. TT was measured using a chemiluminescent immunometric assay. All patients were subjected to a 3-day CGM before making adjustments for hypoglycaemic therapy.

RESULTS

TT positively correlated with the standard deviation of mean blood glucose (SDBG) (P < 0.05), especially in older patients. Linear regression analysis showed that SDBG was associated with HbA1c (β = 0.354, P < 0.001) and TT (β = 0.164, P = 0.008) after adjusting for age, duration of diabetes, body mass index, fasting/postprandial C-peptide, and use of different hypoglycaemic drugs. The cut-off value of TT for predicting glycaemic variability was 14.76 mmol/L according to receiver operating characteristic (ROC) analysis. SDBG, the coefficient of variation, the incremental area under the curve of glucose (AUC) > 10 mmol/L, and AUC night were increased in the group with TT > 14.76 nmol/L (P < 0.01 for all variables). Body mass index and fasting/postprandial C-peptide were lower in the group with TT > 14.76 nmol/L than in the group with TT ≤ 14.76 nmol/L (P < 0.05).

CONCLUSIONS

Circulating TT levels should be assessed in patients with T2D in addition to HbA1c for predicting glycaemic variability. More frequent blood glucose monitoring or CGM is suggested for patients with T2D and high testosterone levels.

CLINICAL TRIALS REGISTRATION

NCT03519529, ClinicalTrials.gov.

Can Low SHBG Serum Concentration Be A Good Early Marker Of Male Hypogonadism In Metabolic Syndrome?

INTRODUCTION

In men suffering from metabolic syndrome, accompanying insulin resistance may result in a lowering of sex hormone-binding globulin (SHBG) plasma levels and cause changes in their androgenic status.

AIM

The objective of the research was to assess selected androgens and SHBG plasma levels in males meeting diagnostic criteria for MS compared to healthy males.

PATIENTS AND METHODS

The group consisted of 65 men aged between 40 and 70 years old fitting IDF metabolic syndrome criteria and 84 controls. Dehydroepiandrosterone (DHEA) and its sulphate (DHEA-S), total and free testosterone and SHBG serum levels were evaluated. Calculated free and bioavailable testosterone were estimated using an algorithm proposed by the International Society for the Study of the Aging Male.

RESULTS

Men diagnosed with MS showed a statistically significant decrease in plasma levels of DHEA in comparison to healthy ones: 11.579 (8.39-15.56) vs 14.014 (9.611-17.125) ng/mL; p = 0.0350, SHBG: 47.46 (35.78-62.83) vs 71.965 (54.45-91.56) nM/L; p<0.0001 and total testosterone: 5.2 (3.8-6.5) vs 6.3 (5.4-8.25) ng/mL; p = 0.0001 (values presented as a median with Q1-Q3).

CONCLUSION

The results suggest that SHBG is a good early marker for metabolic dysregulation in MS, considering its strength of association and significance is comparable to, or better than, those of MS criteria.