Testosterone deficiency: a common, unrecognized syndrome

Analysis of diurnal variation in serum testosterone levels in men with symptoms of testosterone deficiency

BACKGROUND

Testosterone (T) plays a crucial role in various physiological functions in men, and understanding the variations in T levels during the day is essential for diagnosing and treating testosterone deficiency (TD).

AIM

We sought to evaluate the reduction in serum total T (TT) levels throughout the day in men with symptoms of testosterone deficiency and to determine the variables having an impact on the extent of this decline.

METHODS

The study population consisted of a group of men who within 3 months of each other had all undergone both early morning and afternoon TT level measurements. We did not include patients with a history of a prior orchiectomy, testosterone levels below 100 ng/dL or above 1000 ng/dL, a history of androgen deprivation therapy, or patients on T therapy. Statistical analyses were conducted using descriptive statistics, t-tests, chi-square tests, and correlation calculations. Liquid chromatography-tandem mass spectrometry was used to measure TT, and a change in TT levels greater than 100 ng/dL was considered significant. Using multivariable and univariable analysis, we attempted to define predictors of a decrease in afternoon TT levels.

OUTCOMES

The majority of men showed no significant difference in T levels between morning and afternoon.

RESULTS

In total, 506 men with a median age of 65 years were analyzed. The most common comorbidities were hypertension and hyperlipidemia. Levels of TT were measured in the morning and afternoon, and no significant differences in mean T levels based on the time of the test were found. Age was not significantly associated with T levels.

CLINICAL IMPLICATIONS

There was a weak negative correlation between age and the difference between morning and afternoon T levels, with younger men showing more significant variations in T levels. The most considerable differences in T levels were observed in men younger than 30 years. There were no predictors of the magnitude of the T decrease in the afternoon.

STRENGTHS AND LIMITATIONS

Strengths of the study include the number of subjects and the use of liquid chromatography-tandem mass spectrometry for T measurement. Limitations include failure to measure morning and afternoon T levels on the same day, the retrospective nature of the study, and a smaller sample size of patients younger than 30 years.

CONCLUSION

In this study we found no strong link between age and daily T fluctuation, but we observed a decrease in the magnitude of variation with aging. The group experiencing the most significant decline in daily T had higher morning and consistently normal afternoon T levels.

Ameliorative effects of elderberry (Sambucus nigra L.) extract and extract-derived monosaccharide-amino acid on H2O2-induced decrease in testosterone-deficiency syndrome in a TM3 Leydig cell

With aging, men develop testosterone-deficiency syndrome (TDS). The development is closely associated with age-related mitochondrial dysfunction of Leydig cell and oxidative stress-induced reactive oxygen species (ROS). Testosterone-replacement therapy (TRT) is used to improve the symptoms of TDS. However, due to its various side effects, research on functional ingredients derived from natural products that do not have side effects is urgently needed. In this study, using the mitochondrial dysfunction TM3 (mouse Leydig) cells, in which testosterone biosynthesis is reduced by H2O2, we evaluated the effects of elderberry extract and monosaccharide-amino acid (fructose-leucine; FL) on mRNA and protein levels related to steroidogenesis-related enzymes steroidogenic acute regulatory protein (StAR), cytochrome P450 11A1(CYP11A1, cytochrome P450 17A1(CYP17A1), cytochrome P450 19A1(CYP19A1, aromatase), 3β-hydroxysteroid dehydrogenase (3β-HSD), and 17β-hydroxysteroid dehydrogenase(17β-HSD). We analyzed elderberry extract and extract-derived FL for changes in ROS scavenging activity and testosterone secretion. Elderberry extract and FL significantly reduced H2O2-induced intracellular ROS levels, improved testosterone secretion, and increased the mRNA and protein expression levels of steroidogenesis-related enzymes (StAR, 3b-HSD, 17b-HSD, CYP11A1, CYp17A1). However, the conversion of testosterone to estradiol was inhibited by elderberry extract and extract-derived FL, which reduced the mRNA and protein expression of CYP19A1. In conclusion, elderberry extract and FL are predicted to have value as novel functional ingredients that may contribute to the prevention of TDS by ameliorating reduced steroidogenesis.

Intramuscularly injected long-acting testosterone-cholesterol prodrug suspension with three different particle sizes: extended in vitro release and enhanced in vivo safety

The testosterone undecanoate oil solution is the most widely used injection of testosterone for long-acting effects on the market, whereas the formulation carries the potential risk of causing pulmonary vascular embolism, inflammation, and pain at the injection site. Therefore, a sustained-released long-acting injection of testosterone with strong security is urgently exploited. Herein, a poorly water-soluble testosterone-cholesterol prodrug (TST-Chol) was synthesized by esterification. The water solubility of TST-Chol was decreased by 644 folds in comparison to that of testosterone (TST). Moreover, suspensions of TST and TST-Chol were prepared and analyzed in vitro, utilizing three distinct particle sizes: small-sized nanocrystals (SNCs) measuring 300 nm, medium-sized microcrystals (MMCs) measuring 12 μm, and large-sized microcrystals (LMCs) measuring 20 μm. The findings from the in vitro release study indicated that the sustained release of the drug was significantly influenced by the solubility and particle sizes of the suspension. Notably, the suspensions with low water solubility and larger particle sizes exhibited a more desirable sustained-release effect in vitro. Furthermore, the study on pharmacokinetics exhibited that TST-Chol SNCs produced a sustained TST plasma concentration in vivo for up to 40 days and no obvious pathological changes in lung tissue were found. Our study indicated that solubility and particle sizes of suspensions had made a difference in pharmacokinetics and provided a valuable reference for the advancement of long-acting injections.

Effects of Testosterone Treatment on Quality of Life in Patients With Chronic Kidney Disease

Testosterone deficiency (TD) is common and impairs quality of life (QoL) in patients with chronic kidney disease (CKD). However, there are no studies about whether testosterone replacement therapy (TRT) can improve QoL in patients with CKD. Therefore, we investigated the effect of TRT on the QoL of patients with CKD and confirmed the safety of TRT. Twenty-five male patients with stages III–IV CKD whose serum testosterone levels were <350 ng/dl (TD) were enrolled and treated with testosterone gel for 3 months (group II). Age-matched controls with stages III–IV CKD and TD (group I) were recommended to exercise for the same period. Before and after the treatment, the BMI and handgrip strength were checked, serological tests were performed, and questionnaires were administered in both groups. Compared to baseline, there was no significant difference in serum testosterone levels, scores of the 36-Item Short Form Health Survey (SF-36), Aging Males’ Symptoms Scale (AMS), and International Prostate Symptom Score (IPSS), and grip strength in group I after 3 months. In group II, a significant increase in testosterone, hemoglobin (Hb), and hematocrit (Hct) was observed, and grip strength significantly increased after TRT. Significant improvement in scores of SF-36, AMS, and IPSS was also confirmed after TRT in group II. There was a significant difference in testosterone, Hb, Hct, grip strength, and scores of SF-36, AMS, and IPSS between the two groups after 3 months. The patients in group II showed positive results and continued with TRT. Therefore, we conclude that TRT safely improves the QoL and TD symptoms in patients with moderate-to-severe CKD.

Prevalence of testosterone deficiency among aging men with and without morbidities

In this cross-sectional study 1852 men aged 40-70 years attending primary health care were invited to fill out the aging male symptoms (AMS) scale. Out of these, 1222 men were found positive for the AMS and agreed to provide blood samples for the general blood test, lipid profile, glucose levels, and assessment of both total and free testosterone (T) levels. Men were screened for the following morbidities and syndromes: dyslipidemia, arterial hypertension, obesity, type II diabetes, metabolic syndrome, and chronic obstructive pulmonary disease (COPD). Testosterone deficiency was diagnosed if total T ≤ 3.46 ng/mL or free T ≤ 72 pg/mL. Among all 1222 men with positive AMS, decreased blood testosterone levels were detected in 669 men (55%). A total of 402 men were found healthy and 820 men were detected with different morbidities. Out of 669 men with testosterone deficiency, only 2.8% had no co-morbidities and 97.2% were men with co-morbidities. Testosterone levels were found significantly higher among healthy men (median 4.7 ng/mL) as compared to the men with morbidities (median 2.55 ng/mL, p<.001), adjusted for age. Testosterone deficiency was detected in significantly lower proportion of 402 men without co-morbidities as compared to the 820 men with co-morbidities: in 19 men (4.7) and in 650 men (79.3%, p<.05), respectively.

Clinically occult prostate cancer cases may distort the effect of testosterone replacement therapy on risk of PCa

BACKGROUND

Although prostate cancer (PCa) screening is conducted before testosterone replacement therapy (TRT), clinically occult PCa cases may exist.

METHODS

To evaluate whether the possible inclusion of occult PCa cases distorts the effect of TRT on risk of PCa, we followed 776 hypogonadal males (TRT = 400, non-TRT = 376) from a urology center in Germany from 2004 to 2016, with a mean follow-up period of 7 years. We assumed occult cases might take 1-2 years (latency period) to become clinically detectable after receiving TRT. We selected several latency periods (12/18/24 months) and compared the risk of PCa in the TRT and non-TRT group over the latency period, from the end of latency period till the end of follow-up, and over the whole follow-up time.

RESULTS

Overall, 26 PCa cases occurred in the non-TRT group vs 9 cases in the TRT group. Within 18 months of follow-up, 9 cases occurred in the TRT group vs 0 cases in the non-TRT group; from the end of 18 months till the end of follow-up, 26 cases occurred in the non-TRT group vs 0 cases in the TRT group. The adjusted table showed seemingly adverse effects of TRT on PCa development within 18 months (p = 0.0301) and beneficial effects from the end of 18 months till the end of follow-up (p = 0.0069). Similar patterns were observed for 12 or 24 months as the latency period.

CONCLUSIONS

TRT may make occult PCa cases detectable within early phase of treatment and present a beneficial effect in the long run. Future longitudinal studies are needed to confirm findings from our exploratory analyses.

[Andrologic consequences of chronic renal failure: State of the art for the yearly scientific report of the French National Association of Urology]

OBJECTIVE

To describe the state of the art of current knowledge regarding gonadal consequences of end-stage chronic kidney disease (CKD) and renal transplantation.

MATERIAL AND METHOD

A systematic review of the literature search was performed from the databases Medline (NLM, Pubmed) and Embase, focused on the following keywords: "chronic kidney disease"; "chronic renal failure"; "hypogonadism"; "kidney transplantation"; "testicular dysfunction"; "testosterone". Publications obtained were selected based on methodology, language, date of publication (last 10 years) and relevance. Prospective and retrospective studies, in English or French, review articles; meta-analysis and guidelines were selected and analyzed. This search found 383 articles. After reading titles and abstracts, 51 were included in the text, based on their relevance.

RESULTS

The prevalence of hypogonadism in CKD is reported between 24 % and 66 %, and decreases partially after renal transplantation. This is a hypogonadotropic hypogonadism whose pathophysiology is multifactorial, involving mainly a primitive testicular deficit, a hypothalamic-pituitary dysregulation, and an hyperprolactinemia. The consequences of this hypogonadism are not only sexual but also contribute to anemia, sarcopenia, atherosclerosis, and potentially in the progression of CKD. Hypogonadism is an independent risk factor for mortality in CKD patients.

CONCLUSIONS

CKD is frequently associated with an hypogonadism whose correction is validated only in the setting of erectile dysfunction treatment. The other benefits of the correction of hypogonadism in the CKD patients, including overall survival, needs to be evaluated.

Testosterone Replacement Therapy: The Emperor's New Clothes

The mean age of the world population has steadily increased in the last decades, as a result of increased life expectancy and reduced birth rate. Global aging has led to a greater worldwide cost for healthcare: hormonal alterations contribute to the pathogenesis of several conditions and might cause a significant reduction in the perceived sense of well-being. Menopause is archetypal of hormonal alterations occurring during aging: in males, sex hormones do not decrease abruptly, yet testosterone levels decrease steadily and continuously during aging, ultimately resulting in late-onset hypogonadism. Treatment of this condition might mitigate most symptoms; however, testosterone replacement therapy (TRT) should be prescribed only in selected patients and it should not be considered as an antiaging treatment. In recent years, different authors have questioned health risks associated with testosterone treatment; while position statements from many scientific societies seem to be reassuring, the Food and Drug Administration has issued a warning in regard to the possible side effects of this therapy. We aim to review recent controversies and discoveries in regard to TRT.

Natural course of hypogonadism diagnosed during hospitalization in aged male patients

Our aim was to assess short-term natural course of hypogonadism diagnosed during hospitalization for acute disease in aged male patients after discharge. A group of 43 hypogonadal males, aged 86.7±5.7 year, was studied. Serum concentrations of testosterone (T) and gonadotropins (follicle-stimulating hormone, FSH, and luteinizing hormone, LH) were measured in every patient both at admission and one month after discharge. Mean serum T at entry was 115.4±48.0 ng/dl. Hypogonadism was hyper-, hypo-, and normogonadotropic in 20 (46.5%), 20 (46.5%), and 3 (7.0%) patients, respectively. One month after discharge serum T concentrations increased significantly (230.9±135.6 ng/dl, p<0.001). At this point, more than half of the patients (n=27, 62.8%) showed normal serum T concentrations. Both gonadotropins, FSH (p<0.001), and LH (p=0.04) also increased one month after discharge. Approximately, half of the patients (13, 48.1%) who normalized serum T concentrations also showed normal serum gonadotropin concentrations. Patients who normalized their serum T concentrations one month after discharge showed significantly higher baseline values of T (134.7±33.9 ng/dl) than those who persisted with hypogonadism (n=16, 32.7%; 82.8±51.6 ng/dl, p<0.001). Lastly, serum T was the only independent predictor for achieving eugonadal status (OR 1.030; CI 95%, 1.010-1.050; p<0.001). In conclusion, about 63% of aged patients hospitalized for acute illness with hypogonadism discovered during hospitalization spontaneously normalize their serum T concentrations one month after discharge. Serum gonadotropin concentrations also increased after discharge. Serum T levels at admission was an independent predictor for the normalization of serum T concentrations.

Saliva-based biosensors: noninvasive monitoring tool for clinical diagnostics

Saliva is increasingly recognised as an attractive diagnostic fluid. The presence of various disease signalling salivary biomarkers that accurately reflect normal and disease states in humans and the sampling benefits compared to blood sampling are some of the reasons for this recognition. This explains the burgeoning research field in assay developments and technological advancements for the detection of various salivary biomarkers to improve clinical diagnosis, management, and treatment. This paper reviews the significance of salivary biomarkers for clinical diagnosis and therapeutic applications, with focus on the technologies and biosensing platforms that have been reported for screening these biomarkers.

Gender Differences in Child and Adolescent Social Withdrawal: A Commentary

In a manuscript entitled, "Bashful boys and coy girls: A review of gender differences in childhood shyness" Doey et al. (2013) suggest that shyness and its related constructs pose a greater developmental risk for boys compared to girls. They support this claim by citing empirical evidence suggesting that shy and anxiously withdrawn boys are responded to more negatively by important others (i.e., parents, peers, and teachers) and that the relationship between internalizing problems and anxious withdrawal is stronger for boys compared to girls. The principal aim of our commentary is to provide a critical examination of Doey et al.'s conclusions vis-à-vis gender differences in child and adolescent shyness. In this response, we begin by providing important theoretical background regarding shyness and its related constructs. Next, we critically examine the two main arguments the authors use in support of their conclusion through a review of existing empirical and theoretical work as well as the presentation of data from The Friendship Project. These data were analyzed with the specific purpose of providing an empirical test of the hypotheses implicit in Doey et al.'s primary arguments: 1) shy and anxiously withdrawn boys are responded to more negatively than girls and 2) the association between anxious withdrawal and internalizing problems is stronger for boys compared to girls. Our results indicate mixed support for these two claims. Finally, we conclude by suggesting new directions for future researchers interested in clarifying the relationship between gender and both the correlates and outcomes of childhood shyness.

Hypogonadism in aged hospitalized male patients: prevalence and clinical outcome

OBJECTIVE

Male hypogonadism is common in the elderly and has been associated with increased risk of mortality. Our objective has been to assess the prevalence of primary and central hypogonadism in elderly male patients admitted to the hospital because of acute illness. We also evaluated the relationships between gonadal dysfunction and in-hospital mortality.

PATIENTS AND METHODS

150 patients, aged ≥65 years, admitted during 2010 and 2011 in our geriatric unit, were studied. Serum concentrations total, bioavailable and free testosterone, as well as of follicle-stimulating hormone and luteinizing hormone were quantified in every patient. Hypogonadism was defined by the presence of serum testosterone levels lower than 200 ng/dl.

RESULTS

Hypogonadism was found in 80 patients (53.3 %). Serum gonadotropin concentrations were elevated in 43.7 % of these patients, whereas 41.3 % of hypogonadic patients showed normal and 15 % low gonadotropin concentrations. Respiratory tract infection and congestive heart failure were the main causes of hospitalization in hypogonadal men, whereas acute cerebrovascular disease was the main reason for admission in eugonadal patients. Of the 13 patients who died during hospitalization, 12 were hypogonadic. Patients who died showed significantly lower serum levels of total, free and bioavailable testosterone than those found in patients who survived.

CONCLUSION

Our results show that about half of patients admitted for acute illness have hypogonadism, mainly of non-hypergonadotropic type. Gonadal hypofunction is significantly related with in-hospital mortality. A low value of serum testosterone may be a predictor for mortality in elderly male patients.

Serum testosterone and depressive symptoms in severe OSA patients

Obstructive sleep apnoea (OSA), also characterised by hypoxia-related sleep- fragmentation, has been studied in relation to depression and serum testosterone deficit. In middle-aged men, it has been reported the association between depressive mood and low serum testosterone level; however, no data are available about this association in OSA patients. Therefore, the aim of this study was to investigate in adult obese males, affected by severe OSA, the relationship between serum testosterone concentration and depressive symptoms, in order to identify among all measured parameters (serum testosterone morning concentration, polysomnography parameters, body mass index, Epworth Sleepiness Scale) those predictors for OSA-related depression. Forty patients diagnosed with severe OSA and forty subjects for the control-matched group were enroled in the study. The results indicated that the serum testosterone in OSA group was significantly lower than in controls. In addition, the OSA group presented a level of depression although moderate, yet significantly higher than controls. Furthermore, a statistically significant inverse correlation has been found between serum testosterone level and depressive symptoms. Among all variables, serum testosterone level was shown to be the only independent variable significantly predictor for depression in OSA patients.

Serum testosterone levels and clinical outcomes in male hemodialysis patients

BACKGROUND

Studies linking low serum testosterone concentration to adverse clinical outcomes in hemodialysis patients have been relatively small. We investigated the role of testosterone in adverse outcomes and quality of life in an incident cohort of male Canadian hemodialysis patients.

STUDY DESIGN

A prospectively designed multicenter observational study using data from the Canadian Kidney Disease Cohort Study (CKDCS).

SETTING & PARTICIPANTS

Male patients initiating hemodialysis therapy since February 14, 2005, in 3 Canadian centers serving ethnically diverse populations were studied (N = 623).

PREDICTOR

Serum testosterone levels using the International Society of Andrology, International Society for the Study of the Aging Male, and European Association of Urology cutoffs (low, <231 ng/dL; borderline, 231-346 ng/dL; normal, >346 ng/dL).

OUTCOMES

All-cause mortality, fatal and nonfatal cardiovascular (CV) events, and Health Utility Index (HUI)-assessed health-related quality of life.

MEASUREMENTS

Participants completed a structured interview on demographics and medical history and an HUI questionnaire (version 3). Routine laboratory test results captured into the study database, and serum testosterone measured within 3 months after initiation of the baseline hemodialysis session.

RESULTS

During a median follow-up of 20 (range, 1-81) months, 166 (27%) died and 98 (20%) had a CV event. Mean serum testosterone level was 234.1 ± 146.1 (SD) ng/dL. Higher serum testosterone levels were associated with significantly decreased unadjusted risk of death (HR per 10-ng/dL increase, 0.58; 95% CI, 0.37-0.90). There was a statistically significant trend for higher all-cause mortality with low serum testosterone levels in adjusted analyses (P < 0.001). Higher levels of log-transformed testosterone were associated with significantly higher HUI scores (P for trend <0.001), and low levels of serum testosterone were associated significantly with lower HUI scores (P for trend <0.001). Although there was a significant trend in the unadjusted risk of CV events among participants with low serum testosterone levels (P < 0.001), the risk was no longer significant after adjustment for age. There was no significant interaction with age and serum testosterone level tested as continuous variables (P = 0.07).

LIMITATIONS

A short follow-up period and serum testosterone measured on a single occasion.

CONCLUSIONS

Low serum testosterone concentration may be a modifiable risk factor for adverse outcomes and poor quality of life in male hemodialysis patients. This hypothesis should be tested in randomized controlled trials.

Endocrine effects of chronic opioid therapy: implications for clinical management

SUMMARY Over the past few decades, the use of opioids in the management of chronic pain conditions has greatly increased. As opioid utilization has expanded, so has the recognition of associated hormonal derangements. These hormonal disturbances involve disruption, predominantly of the hypothalamic–pituitary–gonadal axis, and can affect both men and women treated with opioids. The best recognized of these hormonal disorders is opioid-associated androgen deficiency. Opioid-associated androgen deficiency is most likely to occur with prolonged, high-dose opioid therapy and may be associated with the development of other conditions such as depression, osteoporosis and possible hyperalgesia. Once identified, opioid-associated androgen deficiency should be managed with appropriate hormonal replacement therapy and patients should be closely monitored for adequacy of treatment and treatment-associated adverse events.

Transversal European survey on testosterone deficiency diagnosis

BACKGROUND

Despite being one of the relevant public health threats among ageing men, testosterone deficiency syndrome (TDS) is under-recognized and under-diagnosed.

OBJECTIVE

To assess current clinical practices of European physicians regarding diagnosis and management of TDS compared with current guidelines.

METHODS

Postal survey conducted June-November 2008 in France, Germany, Italy and Spain among urologists, endocrinologists and general practitioners to collect information regarding knowledge of TDS.

RESULTS

Among 801 respondents, the majority of endocrinologists and urologists had received training on TDS, either initially or as part of continuous medical education. TDS was recognized by 86.5% of physicians as a true clinical entity, and estimated the prevalence at 10-15% of the male population; 73.5% considered that symptoms and a low level of testosterone were required for diagnosis. Treatment preferences were quarterly intramuscular injections (26.3% of physicians), percutaneous gels (23.9%), matrix patch (21.2%), semi-monthly injections (15.4%) and oral therapy (13.4%). Adverse effects of testosterone replacement therapy, such as benign prostatic hyperplasia and prostate cancer, were a concern for physicians.

CONCLUSIONS

TDS management appeared to be close to that recommended in international guidelines. Signs and symptoms of testosterone deficiency were fairly well known, but some diagnostic and treatment variations were observed.

Complaint of insomnia as a predictor of aging symptoms in males at a men's health clinic

INTRODUCTION

Issues of men's health have been greatly researched by scholars in recent decades. At men's health clinics, many patients complain of both insomnia and aging males' symptoms (AMS). These symptoms might be influenced by biological, psychological or even social factors. The aim of this study was to investigate different aspects of the relationship between insomnia and aging symptoms.

METHODS

This cross-sectional study included 231 males from a men's health clinic. Participants completed a set of general data and screening assessments, including the AMS rating scale, insomnia severity index (ISI), Beck depression inventory-II (BDI-II) and Beck anxiety inventory Chinese version (BAI), to investigate the severity of aging symptoms, insomnia, depression and anxiety.

RESULTS

The ISI correlated significantly with the AMS scale, both with (partial correlation coefficient = 0.470) and without (r = 0.580) controlled variances of depression and anxiety. Using linear regression, aging symptoms were statistically predicted by the severity of the ISI, and a substantial proportion of the variance was explained (adjusted R(2) = 0.410). When all variables were included, this proportion rose to 55.3% (adjusted R(2) = 0.553).

CONCLUSION

We suggest that insomnia is a good predictor of aging symptoms across all age groups of men.

The female menstrual cycle does not influence testosterone concentrations in male partners

BACKGROUND

The time of ovulation has since long been believed to be concealed to male heterosexual partners. Recent studies have, however, called for revision of this notion. For example, male testosterone concentrations have been shown to increase in response to olfactory ovulation cues, which could be biologically relevant by increasing sexual drive and aggressiveness. However, this phenomenon has not previously been investigated in real-life human settings. We therefore thought it of interest to test the hypothesis that males' salivary testosterone concentrations are influenced by phases of their female partners' menstrual cycle; expecting a testosterone peak at ovulation.

METHODS

Thirty young, healthy, heterosexual couples were recruited. During the course of 30-40 days, the women registered menses and ovulation, while the men registered sexual activity, physical exercise, alcohol intake and illness (confounders), and obtained daily saliva samples for testosterone measurements. All data, including the registered confounders, were subjected to multiple regression analysis.

RESULTS

In contrast to the hypothesis, the ovulation did not affect the testosterone levels, and the resulting testosterone profile during the menstrual cycle was on the average flat. The specific main hypothesis, that male testosterone levels on the day of ovulation would be higher than day 4 of the cycle, was clearly contradicted by a type II error(β)-analysis (< 14.3% difference in normalized testosterone concentration; β = 0.05).

CONCLUSIONS

Even though an ovulation-related salivary testosterone peak was observed in individual cases, no significant effect was found on a group level.

Tissue-selective regulation of androgen-responsive genes

INTRODUCTION

Androgens regulate a wide array of physiological processes, including male sexual development, bone and muscle growth, and behavior and cognition. Because androgens play a vital role in so many tissues, changes in androgen signaling are associated with a plethora of diseases. How such varied responses are achieved by a single stimulus is not well understood. Androgens act primarily through the androgen receptor (AR), a hormone nuclear receptor that is expressed in a select variety of tissues.

METHODS

In order to gain a better understanding of how the tissue-selective effects of androgens are achieved, we performed a comparison of microarray data, using previously published datasets and several of our own microarray datasets. These datasets were derived from clinically relevant, AR-expressing tissues dissected from rodents treated with the full androgen dihydrotestosterone (DHT).

RESULTS

We found that there is a diverse response to DHT, with very little overlap of androgen regulated genes in each tissue. Gene ontology analyses also indicated that, while several tissues regulate similar biological processes in response to DHT, most androgen regulated processes are specific to one or a few tissues. Thus, it appears that the disparate physiological effects mediated by androgens begin with widely varying effects on gene expression in different androgen-sensitive tissues.

CONCLUSION

The analysis completed in this study will lead to an improved understanding of how androgens mediate diverse, tissue-specific processes and better ways to assess the tissue-selective effects of AR modulators during drug development.

Endogenous testosterone, endothelial dysfunction, and cardiovascular events in men with nondialysis chronic kidney disease

BACKGROUND AND OBJECTIVES

Deterioration of kidney function impairs testosterone production, with hypogonadism being common in men with chronic kidney disease (CKD). In nonrenal populations, testosterone is suggested to participate in the atherosclerotic process. In male dialysis patients, we showed that low testosterone increases the risk of mortality. We here studied plausible links among testosterone levels, vascular derangements, and cardiovascular events in nondialysis CKD men.

DESIGN, SETTING, PARTICIPANTS, & METHODS

This was a cross-sectional analysis in which flow-mediated dilation (FMD) was assessed in 239 CKD male patients (stages 1 to 5; mean age 52 ± 12 years), together with routine measurements, serum total and free testosterone, and follow-up for cardiovascular outcomes.

RESULTS

Total and free testosterone levels decreased in parallel with the reduction of kidney function. Multiple regression analyses showed that total and free testosterone significantly and independently contributed to explain the variance of FMD. After a median follow-up of 31 months (range 8 to 35 months), 22 fatal and 50 nonfatal cardiovascular events occurred. In Cox analysis, the risk of cardiovascular events was reduced by 22% for each nanomole-per-liter increment of total testosterone. This reduced risk persisted after adjustment for age, renal function, diabetes mellitus, previous cardiovascular history, C-reactive protein, albumin, and FMD. The same was true for free testosterone concentrations.

CONCLUSIONS

The reduction in endogenous testosterone levels observed with progressive CKD was inversely associated with endothelial dysfunction and exacerbated the risk of future cardiovascular events in nondialysis male CKD patients.

Endogenous testosterone and mortality in male hemodialysis patients: is it the result of aging?

BACKGROUND AND OBJECTIVES

Low serum testosterone levels in hemodialysis (HD) patients have recently been associated with cardiovascular risk factors and increased mortality. To confirm this observation, we investigated the predictive role of serum total testosterone levels on mortality in a large group of male HD patients from Turkey.

DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS

A total of 420 prevalent male HD patients were sampled in March 2005 and followed up for all-cause mortality. Serum total testosterone levels were measured by ELISA at baseline and studied in relation to mortality and cardiovascular risk profile.

RESULTS

Mean testosterone level was 8.69 ± 4.10 (0.17 to 27.40) nmol/L. A large proportion of patients (66%) had testosterone deficiency (<10 nmol/L). In univariate analysis, serum testosterone levels were positively correlated with creatinine and inversely correlated with age, body mass index, and lipid parameters. During an average follow-up of 32 months, 104 (24.8%) patients died. The overall survival rate was significantly lower in patients within the low testosterone tertile (<6.8 nmol/L) compared with those within the high tertile (>10.1 nmol/L; 64 versus 81%; P = 0.004). A 1-nmol/L increase in serum testosterone level was associated with a 7% decrease in overall mortality (hazard ratio 0.93; 95% confidence interval 0.89 to 0.98; P = 0.01); however, this association was dependent on age and other risk factors in adjusted Cox regression analyses.

CONCLUSIONS

Testosterone deficiency is common in male HD patients. Although testosterone levels, per se, predicted mortality in this population, this association was largely dependent on age.

Prevalence and clinical implications of testosterone deficiency in men with end-stage renal disease

BACKGROUND

Abnormally low serum testosterone levels were recently associated with an increased mortality risk in male dialysis patients. However, the prevalence of testosterone deficiency in end-stage renal disease (ESRD) is not well defined. We hereby explore the prevalence and correlates of clinical testosterone deficiency in a large cohort of ESRD male patients.

METHODS

Two hundred and sixty ESRD men [median age 59 (25th-75th percentile 48-67)  years] were included. Testosterone concentration and testosterone deficiency (<10 nmol/L) were studied in relation to clinically evident cardiovascular disease and markers of inflammation at baseline as well as deaths registered during the following 36 months.

RESULTS

Testosterone deficiency was present in 44% of the patients, while 33% showed testosterone insufficiency (10-14 nmol/L), and only 23% had normal testosterone values (>14 nmol/L). Testosterone was strongly and inversely correlated to inflammatory markers (CRP, IL-6 and fibrinogen), even after correction for age and sex hormone-binding globulin. In a crude spline curve, low testosterone concentrations were associated with worse outcome. A clinical condition of testosterone deficiency was independently associated with cardiovascular co-morbidity [odds ratio (OR) 2.51; 95% confidence interval (CI) 1.32-4.76] and death (OR 2.00; 95% CI 1.01-3.97) in logistic regression analyses.

CONCLUSIONS

Testosterone deficiency is a common finding among male ESRD patients, and it is independently associated with inflammation, cardiovascular co-morbidity and outcome. Future studies are needed to determine the potential adverse effects of male hypogonadism in ESRD and the possibility of improving risk profile, quality of life, and ultimately outcome with testosterone supplementation in these patients.

Testosterone and unconscious positive priming increase human motivation separately

Clinical observations suggest that testosterone generates unconscious broad-spectrum motivations to act. It has also been suggested that subliminal positive-priming techniques also unconsciously enhances motivation for action. This placebo-controlled study examined the separate and possible joint contributions of these assumed unconscious sources of human motivation. Healthy females were administered 0.5 mg sublingual testosterone or placebo. Next, they were subliminally primed with action concepts that were paired with positive or neutral cues, and indicated their motivation for the respective action. Testosterone and positive priming both increased the motivation for action, but there was no joint contribution. Possibly, testosterone pushed the motivational brain system to a limit allowing no add-on contribution by priming, but our data also agree with neuroimaging evidence showing that the neural (subcortical and cortical) pathways of motivation can be functionally disconnected by testosterone administration.

Men's health, low testosterone, and diabetes: individualized treatment and a multidisciplinary approach

Testosterone plays a critical role in male reproductive and metabolic functioning. Serum testosterone levels decrease with age, and low testosterone is associated with a variety of comorbidities, including insulin resistance, type 2 diabetes, obesity, metabolic syndrome, and cardiovascular disease. Men with type 2 diabetes have been shown to have significantly lower testosterone levels than men without diabetes. Several forms of testosterone replacement therapy (eg, oral, injectable, buccal, transdermal preparations) are available for use in the United States. The primary goals of testosterone therapy are to restore physiologic testosterone levels and reduce the symptoms of hypogonadism. Testosterone therapy may be a viable option in some men with diabetes and low testosterone; however, clinicians must be aware of contraindications to therapy (eg, prostate cancer and male breast cancer), implement appropriate monitoring procedures, and ensure that patient expectations are realistic regarding treatment outcome. Data suggest that testosterone therapy may have a positive effect on bones, muscles, erythropoiesis and anemia, libido, mood and cognition, penile erection, cholesterol, fasting blood glucose, glycated hemoglobin, insulin resistance, visceral adiposity, and quality of life. Sexual health may be a window into men's health; thus, more effective communication strategies are needed between clinicians and men with diabetes to ensure that sexual health topics are adequately addressed. Diabetes educators can play a key role in screening for low testosterone, providing relevant information to patients, and increasing clinician awareness of the need to address men's sexual health and implement appropriate strategies. Multidisciplinary care and individualized treatment are needed to optimize outcome.

Ultrasensitive detection of testosterone using conjugate linker technology in a nanoparticle-enhanced surface plasmon resonance biosensor

A rationally designed oligoethylene glycol linker conjugate to testosterone was synthesised and covalently immobilized on a surface plasmon resonance (SPR) biosensor surface. The sensing surface was stable for more than 330 binding and regeneration cycles allowing a high degree of re-use. This surface was then used in the development of an ultrasensitive immunobiosensor system for testosterone in buffer utilizing both secondary antibody and gold nanoparticle signal enhancement. The mechanism for the increased sensitivity results from increased binding mass and a gold plasmon coupling effect. The addition of a secondary antibody with an attached gold nanoparticle increased the signal sensitivity of the assay 12.5-fold compared with primary antibody alone. In the enhanced format the assay had limits of detection (LOD) of 3.7 pgml(-1) with standard in running buffer, and 15.4 pgml(-1) in a stripped human saliva matrix. This immunobiosensor system has sufficient sensitivity to measure testosterone across the broad physiologically relevant range in male saliva (29-290 pgml(-1)) in under 13 min allowing monitoring of testosterone in near real-time.