New horizons in testosterone and the ageing male

Prevalence of new-onset diabetes mellitus after kidney transplantation: a systematic review and meta-analysis

AIMS

Post-transplant diabetes is a prevalent and consequential complication following kidney transplantation, which significantly augments the risk of cardiovascular disease, graft loss, infection, and mortality, thereby profoundly impacting both graft and patient survival. However, the early stages of post-transplant diabetes often go unnoticed or receive inadequate management. Consequently, this study systematically assesses the incidence of new-onset diabetes after kidney transplantation with the aim to enhance medical staff awareness regarding post-transplantation diabetes and provide clinical management guidance.

METHODS

We conducted a comprehensive search across multiple databases including PubMed, Web of Science, Embase, The Cochrane Library, CNKI, Wanfang, VIP, and SinoMed until September 21, 2023. Data extraction was performed using standardized tables and meta-analysis was conducted using Stata 16.0 software. A random effects model was employed to estimate the combined prevalence along with its corresponding 95% confidence interval. The source of heterogeneity was explored using subgroup analysis and sensitivity analysis, while publication bias was assessed through funnel plot and Egger's test. This study has been registered with PROSPERO under the registration number CRD42023465768.

RESULTS

This meta-analysis comprised 39 studies with a total sample size of 16,584 patients. The prevalence of new-onset diabetes after transplantation was found to be 20% [95% CI (18.0, 22.0)]. Subgroup analyses were conducted based on age, gender, body mass index, family history of diabetes, type of kidney donor, immunosuppressive regimen, acute rejection episodes, hepatitis C infection status and cytomegalovirus infection.

CONCLUSIONS

The incidence of post-kidney transplantation diabetes is substantial, necessitating early implementation of preventive and control measures to mitigate its occurrence, enhance prognosis, and optimize patients' quality of life.

CLINICAL TRIAL REGISTRATION

PROSPERO: CRD42023465768.

Dietary fat quality and serum androgen concentrations in middle-aged men

BACKGROUND/OBJECTIVES

Average testosterone concentrations in men have declined over the last few decades. The reasons for this are not fully known, but changes in dietary fat quality have been suggested to have a role. This study aimed to investigate the associations of different dietary fatty acids with serum androgen concentrations.

SUBJECTS/METHODS

A total of 2546 men with a mean age of 53 from the Kuopio Ischaemic Heart Disease Risk Factor Study were included in this cross-sectional study. Associations between dietary saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA) and trans (TFA) fatty acids and concentrations of serum total and free testosterone and steroid hormone binding globulin (SHBG) were analyzed with analysis of covariance and linear regression analysis. Associations of isocaloric replacement of nutrients and androgen concentrations were analyzed with multivariate nutrient-density models.

RESULTS

After adjustment for age, examination year and energy intake, higher SFA intake was associated with higher serum total and free testosterone and SHBG concentrations, and higher PUFA intake with lower concentrations. However, the associations were attenuated and not statistically significant after further adjustments for potential confounders. MUFA and TFA intakes were not associated with androgen concentrations. In isocaloric substitution models, replacing dietary protein with SFA was associated with higher serum total testosterone and SHBG concentrations. After excluding men with history of CVD or diabetes (n = 1021), no statistically significant associations were found.

CONCLUSIONS

Dietary fat quality was not independently associated with serum androgen concentrations in middle-aged men. However, replacing protein with SFA may be associated with higher serum androgen concentrations.

Ethnic differences in serum testosterone concentration among Malay, Chinese and Indian men: A cross-sectional study

OBJECTIVE

To investigate non-urological patients with multiple comorbidities for factors contributing towards differences in testosterone concentration in multiethnic Malaysian men.

DESIGN

An observational study.

PATIENTS

Sexually active men, ≥40 years, with no known urological problems, were recruited at the phlebotomy clinic at our centre.

MEASUREMENTS

A brief history along with latest fasting lipid profile and plasma glucose levels were obtained. An Aging Male Symptoms questionnaire was administered; waist circumference (WC) and serum testosterone concentration were measured.

STATSTICAL ANALYSIS

Analysis of testosterone concentration between Malay, Indian and Chinese men was performed. Statistical tests such as analysis of variance, χ² test, univariate and multivariable regression were performed. Any p < .05 was noted as statistically significant.

RESULTS

Among the 604 participants analysed, mean testosterone concentration was significantly lower in Malays (15.1 ± 5.9 nmol/L) compared to the Chinese (17.0 ± 5.9 nmol/L) and Indian (16.1 ± 6.5 nmol/L) participants. The mean WC was also found to be higher among the Malays (96.1 ± 10.9 cm) compared to Chinese (92.6 ± 9.6 cm) and Indians (95.6 ± 9.9 cm). Testosterone concentration tended to be lower with higher age, but this was not statistically significant (p > .05). In the multivariable analysis only Malay ethnicity, WC ≥ 90 cm and low high-density lipoprotein (HDL) were associated with lower testosterone concentration.

CONCLUSION

In this study, Malaysian men of Malay origin had lower testosterone concentration compared with Indian and Chinese men. WC and low HDL were also associated with lower testosterone concentrations.

Influence on the adult male Leydig cell biomarker insulin‐like peptide 3 of maternal exposure to estrogenic and anti‐androgenic endocrine disrupting compound mixtures: A retrospective study

Insulin-like peptide 3 (INSL3) is a peptide biomarker secreted specifically by the mature Leydig cells of the testes. It is constitutive, has low within-individual variance, and effectively measures the functional capacity of Leydig cells to make testosterone. In young adult men there is a large 10-fold range of serum INSL3 concentration, persisting into old age, and implying that later hypogonadal status might be programmed in early life. To determine whether maternal exposure to environmental endocrine disrupting compounds (EDCs) influences adult serum INSL3 concentration, using a retrospective paradigm, INSL3 was measured in young adult male rats (80-90 days) from the F1 generation of females maternally exposed to varied doses of bisphenol A (BPA), butylparaben, epoxiconazole, and fludioxonil as single compounds, as well as estrogenic and anti-androgenic mixtures of BPA and butylparaben, and di(2-ethylhexyl) phthalate and procymidone respectively. A mixture of BPA and butylparaben significantly reduced circulating INSL3 concentration in adult male progeny. The remaining compounds or mixtures tested, though sufficient to induce other effects in the F1 generation were without significant effect. Maternal exposure to low concentrations of some EDCs may be a contributing factor to the variation in the Leydig cell biomarker INSL3 in young adulthood, though caution is warranted translating results from rats to humans.

Frailty and testosterone level in older adults: a systematic review and meta-analysis

PURPOSE

We conducted a systematic review to evaluate the relationship between total testosterone (TT), free testosterone (fT), or sex hormone-binding globulin (SHBG) and frailty in older adults.

METHODS

We systematically searched nine databases (e.g. MEDLINE, Embase, ACP Journal Club, and the Cochrane library et al.) for papers on frailty and androgen levels published up to October 10, 2021. We calculated the odds ratio (OR) for the relationship between testosterone level and frailty by performing meta-analysis.

RESULTS

The search strategy yielded 311 hits in all databases combined. Eleven (seven cross-sectional studies and four cohort studies) met the inclusion criteria for meta-analysis. Among cross-sectional studies, meta-analysis revealed a significant association between TT and frailty in men (OR = 1.37 [95% CI 1.09, 1.72]) not women (OR = 1.06 [0.84, 1.34]). The fT was also significantly association with frailty in men (OR = 1.55 [1.06, 2.25] not women (OR = 1.35 [0.91, 2.01]). Cohort studies showed the same result in TT (OR = 1.09 [1.02, 1.18]) and fT (OR = 1.15 [1.02, 1.30]) for men. We did not find a significant association between SHBG and frailty.

CONCLUSION

The findings of this systematic review and meta-analysis suggest that TT and fT were significantly associated with frailty in older men but not women.

D-Chiro-Inositol improves testosterone levels in older hypogonadal men with low-normal testosterone: a pilot study

BACKGROUND

Several recent journal articles report that D-chiro-inositol (DCI), primarily known as insulin second messenger, influences steroidogenesis. In particular, new evidence is arising on DCI ability to regulate aromatase expression and testosterone biosynthesis. In this regard, DCI administration could represent a good therapeutic opportunity in case of reduced levels of testosterone. Older men generally have lower testosterone concentrations than younger men, and recent randomized controlled trials have examined whether testosterone treatment might improve health outcomes in this age group. There is limited information about the safety of testosterone replacement therapy in these men, hence DCI could represent an interesting alternative for future trials. Therefore, this study aims to evaluate the effect of DCI treatment on testosterone levels in older male patient.

RESULTS

Ten older men with basal low testosterone levels were enrolled in this study. Patients took 600 mg of DCI, two-times per day, for 30 days. We evaluated hormonal and glycaemic parameters, weight, waist circumference, and Body-Mass Index at baseline (T0) and after 30 days (T1). Finally, all patients also filled in the standardized International Index of Erectile Function questionnaire and performed the Handgrip test at T0 and T1. Men receiving DCI showed increased androgen and reduced oestrogen concentrations, and improved glycaemic profiles. DCI was also associated with reduced weight, Body-Mass Index, waist circumference, and improved grip strength and self-reported sexual function. All these effects led to the improvement of sexual function and physical strength.

CONCLUSIONS

In this pilot study, DCI treatment improved the levels of testosterone and androstenedione at the expense of oestrogens in elder men with low basal levels of these hormones without adverse effects.

TRIAL REGISTRATION

Clinicaltrials.gov: D-chiroinositol Administration in Hypogonadal Males, NCT04708249.

Regular aerobic exercise improves sexual function assessed by the Aging Males' Symptoms questionnaire in adult men

The leading cause of aging-induced male-specific disorders such as physical, mental and/or sexual symptoms is testosterone deficiency. Although aerobic exercise is suggested to improves circulating testosterone levels, physical fitness, depressive symptoms, and sexual function, the effect of regular aerobic exercise on aging-induced disorders has not yet been clarified. Here we performed cross-sectional and interventional studies to identify the effect of aerobic exercise on aging-induced disorders assessed by the Aging Males' Symptoms questionnaire (AMS). In study 1, the relationship between aerobic exercise capacity (i.e. peak oxygen consumption) and AMS scores were cross-sectionally examined in 169 adult men. In study 2, the effect of a 12-week regular aerobic exercise on AMS scores was longitudinally investigated in 18 adult men. In study 1, the AMS-total, AMS-somatic, AMS-psychological, and AMS-sexual scores were significantly correlated to aerobic exercise capacity even after considering age and testosterone levels. In study 2, 12-week aerobic exercise training significantly improved AMS-sexual and tended to improve AMS-total scores. Additionally, an increase in vigorous physical activity was correlated to improve in the AMS-sexual score. These results suggest that regular aerobic exercise is an effective strategy to improve aging-induced disorders in men.

Testosterone deficiency syndrome: Diagnosis and treatment

The testosterone deficiency syndrome (TDS) is a very common clinical and biochemical condition that affects approximately 2-5% men over the age of 40. From a clinical point of view, it is usually associated with decreased sexual desire and activity, erectile dysfunction, low energy and mood swings, along with T<8-12 nmol/l levels. Questionnaires are not useful in screening but may be useful for diagnosis and follow-up. Its diagnosis requires the presentation of multiple hypogonadism symptoms together with two morning T tests below the acceptable limits. LH and SHBG levels can be useful to determine the cause and the free T level, respectively. Contraindications for treatment are active prostate cancer, stage IV heart failure, breast cancer, desired fertility and hematocrit values over 54%. Treatment is based on the cause of TDS, if any, along with testosterone supplementation. The objective is to achieve normal testosterone levels. Follow-up includes clinical history, analysis (PSA, T+SHBG, hematocrit, glucose and lipid profile) and rectal examination, 3, 6 and 12 months after beginning treatment.

Testosterone replacement therapy: Pre-treatment sex hormone-binding globulin levels and age may identify clinical subgroups

BACKGROUND

Testosterone replacement therapy (TRT) improves health in some but not all men with type 2 diabetes (T2DM) and adult-onset testosterone deficiency (TD). Such heterogeneity is compatible with the concept of patient subgroups that respond differently to therapy.

OBJECTIVES

Use baseline SHBG and age to identify putative subgroups that demonstrate different responses in variables such as waist circumference and HbA1c following TRT.

MATERIALS AND METHODS

A randomized double-blind trial approach was used to recruit and randomize men with T2DM and adult-onset TD into placebo and TRT-treated groups. Multiple regression was used to study differences between groups.

RESULTS

Baseline SHBG and change in SHBG (∆SHBG) were inversely related in the TRT group. Both median values of SHBG and age mediated the effect of TRT on ∆SHBG depending on whether baseline values were ≤ or>median (28.1 nmol/L, 63 years, respectively). In men with both SHBG ≤ 28.1 nmol/L and age ≤ 63 years (subgroup 1), TRT was positively associated with ∆SHBG (c = 4.67, 95%CI 1.17-8.16, P = .010) while in those with SHBG > 28.1 nmol/L and age > 63.1 years (subgroup 4) the association was inverse (c = -7.07, 95%CI -11.64 to -2.49, P = .003). The association between TRT and change (∆) in waist circumference, HbA1c and International Index of Erectile Function (IIEF) score differed between subgroups; in subgroup 4 but not subgroup 1, the therapy was significantly associated with ∆waist circumference, ∆HbA1c and ∆IIEF.

DISCUSSION

Though the mechanism remains unclear, our finding of different responses to TRT in terms of change in waist circumference, HbA1c and IIEF score supports the concept of subgroups in men with T2DM and adult-onset TD.

CONCLUSION

Our approach may provide a basis for identifying men who will or will not derive benefit from TRT though a larger study is required.

A review of the evolving landscape between the consumer Internet and men's health

Internet adoption continues to increase as broadband access and mobile connectivity penetrate developing global markets. Alongside increasing adoption, the Internet continues to evolve and usher in new modes of user interaction. Social media and search engines have facilitated the emergence of the participatory web, in which users are able to contribute content, form online communities, and disseminate information. This participatory web is reshaping the patient-physician relationship as patients are able to search for medical information, directly engage with healthcare practitioners through social media, and make therapeutic decisions via online marketplaces. The ability for patients to self-diagnose and self-treat is highly relevant to andrology, given that men have a baseline reluctance to visit healthcare providers. Furthermore, men's health issues such as erectile dysfunction and male infertility are stigmatized, with men turning to the Internet for guidance. The focus of this review is to survey the academic literature that evaluates the quality of online content for four common men's health conditions: hypogonadism, male infertility, erectile dysfunction, and Peyronie's disease.

Increased estrogen level can be associated with depression in males

BACKGROUND

Several studies have shown a positive association between depression and obesity; however the underlying mechanisms are not fully understood. It is not known if this association is driven by altered sex hormone levels in men due to increased BMI.

PATIENTS AND METHODS

Data were obtained from the LIFE-Adult-Study, a population-based cohort study. A total of 3925 men (2244<60years and 1681>60years) were included into analyses. Associations between BMI, sex hormones and depressive symptomatology according to CES-D score were evaluated.

RESULTS

Obese men had compared to normal weight controls lower total testosterone (12.6±4.7 vs 19.4±5.5 nmol/L, p<0.001 in <60years, and 13.8±6.9 vs 18.3±5.9 nmol/L, p<0.001 in >60years group) and free testosterone (249.0±73.9 vs 337.2±82.0pmol/L, p<0.001, and 217.8±71.2 vs 263.4±72.2pmol/L, p<0.001), and increased estradiol in older group only (97.3±43.0 vs 82.3±34.2pmol/L, p<0.001 in obese). Men <60years old with depressive symptomatology had higher estradiol levels compared to those without depressive symptomatology (96.3±40.7 vs 84.4±36.6pmol/L, p<0.001), however no association with BMI was observed.

CONCLUSIONS

Selected sex hormone parameters were significantly different in overweight and obese compared to normal weight males and certain differences could be seen between younger and older males. Depressive symptomatology was associated with increased estradiol levels in younger men, regardless of BMI.

Testosterone in advance age: a New Zealand longitudinal cohort study: Life and Living in Advanced Age (Te Puāwaitanga o Ngā Tapuwae Kia Ora Tonu)

OBJECTIVES

Serum testosterone (T) levels in men decline with age. Low T levels are associated with sarcopenia and frailty in men aged >80 years. T levels have not previously been directly associated with disability in older men. We explored associations between T levels, frailty and disability in a cohort of octogenarian men.

SETTING

Data from all men from Life and Living in Advanced Age Cohort Study in New Zealand, a longitudinal cohort study in community-dwelling older adults.

PARTICIPANTS

Community-dwelling (>80 years) adult men excluding those receiving T treatment or with prostatic carcinoma.

OUTCOMES MEASURES

Associations between baseline total testosterone (TT) and calculated free testosterone (fT), frailty (Fried scale) and disability (Nottingham Extended Activities of Daily Living scale (NEADL)) (baseline and 24 months) were examined using multivariate regression and Wald's χ² techniques. Subjects with the lowest quartile of baseline TT and fT values were compared with those in the upper three quartiles.

RESULTS

Participants: 243 men, mean (SD) age 83.7 (2.0) years. Mean (SD) TT=17.6 (6.8) nmol/L and fT=225.3 (85.4) pmol/L. On multivariate analyses, lower TT levels were associated with frailty: β=0.41, p=0.017, coefficient of determination (R²)=0.10 and disability (NEADL) (β=-1.27, p=0.017, R²=0.11), low haemoglobin (β=-7.38, p=0.0016, R²=0.05), high fasting glucose (β=0.38, p=0.038, R²=0.04) and high C reactive protein (CRP) (β=3.57, p=0.01, R²=0.06). Low fT levels were associated with frailty (β=0.39, p=0.024, R²=0.09) but not baseline NEADL (β=-1.29, p=0.09, R²=0.09). Low fT was associated with low haemoglobin (β=-7.83, p=0.0008, R²=0.05) and high CRP (β=2.86, p=0.04, R²=0.05). Relationships between baseline TT and fT, and 24-month outcomes of disability and frailty were not significant.

CONCLUSIONS

In men over 80 years, we confirm an association between T levels and baseline frailty scores. The new finding of association between T levels and disability is potentially relevant to debates on T supplementation in older men, though, as associations were not present at 24 months, further work is needed.

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

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