The natural history of symptomatic androgen deficiency in men: onset, progression, and spontaneous remission

Sarcopenic obesity and reduced BMD in young men living with HIV: body composition and sex steroids interplay

PURPOSE

Sex steroids play a key role on male bone homeostasis and body composition (BC), their role in men living with HIV (MLWH) is less recognized. This study aimed at investigating the prevalence of low BMD, sarcopenia, and sarcopenic obesity (SO) and their relationship with sex steroids in MLWH aged < 50.

METHODS

Prospective, cross-sectional, observational study on MLWH younger than 50 (median age 47.0 years). BC and BMD were evaluated with DXA. Two different definitions of sarcopenia were applied: appendicular lean mass/height2 (ALMI) < 7.26 kg/m2 or appendicular lean mass/body weight (ALM/W) < 28.27%. Low BMD was defined for Z-score < -2.0. Sarcopenia coupled with obesity identified SO. Serum total testosterone (T) and estradiol (E2) were measured by LC-MS/MS; free testosterone (cFT) was calculated by Vermeulen equation.

RESULTS

Sarcopenia was detected in 107 (34.9%) and 44 (14.3%) out of 307 MLWH according to ALMI and ALM/W, respectively. The prevalence of SO was similar by using both ALMI (11.4%) and ALM/W (12.4%). Sarcopenic and SO MLWH had lower total T and cFT in both the definition for sarcopenia. BMD was reduced in 43/307 (14.0%). Serum E2 < 18 pg/mL was an independent contributing factor for sarcopenia, SO, and low BMD.

CONCLUSIONS

T and E2 are important determinants of BC even in MLWH. This is among the first studies investigating the distribution of obesity phenotypes and the prevalence of SO among MLWH showing that SO is present in 11-12% of enrolled MLWH regardless of the definition used. However, deep differences emerged using two different diagnostic definitions.

The Palliative and Antioxidant Effects of Hesperidin against Lead-Acetate-Induced Testicular Injury in Male Wistar Rats

Lead (Pb)-induced reprotoxicity is a detrimental consequence of Pb exposure, which results in abnormal spermatogenesis, testicular degeneration, and pathogenic sperm changes. The association between impaired male reproductive function and Pb-induced oxidative stress (OS) has been demonstrated, with consequent testicular antioxidant deficiency. The current study investigated the protective role of the natural antioxidant hesperidin (HSD) against lead-acetate (PbAc)-induced testicular toxicity. Male Wistar rats (n = 40) were randomly divided into four experimental groups: Group I (negative control) received 2.0 mL/kg BW 0.9% saline; Group II received 100 mg/kg BW PbAc; Group III received 100 mg/kg BW HSD; and Group IV received HSD two hours before PbAc using the abovementioned doses. The treatments were administered daily for 30 consecutive days. The results showed that HSD treatment significantly restored PbAc-induced decrease in body, epididymal, and testicular weights as well as in semen parameters, reproductive hormones, and testicular markers of OS. Reduced MDA levels and improved testicular histopathological findings were also observed. Collectively, this study sheds light on the preventive role of HSD against PbAc-induced testicular injury, which is mediated via the suppression of OS and the modulation of reproductive hormones as well as the plausibility of HSD being used as a supplementary therapeutic option for recovery.

Update on acquired hypogonadism in men living with HIV: pathogenesis, clinic, and treatment

Hypogonadism is a frequent finding among men living with HIV (MLWH) and it seems to occur earlier in comparison with the general male population. Although the prevalence of hypogonadism in MLWH has significantly lowered thanks to advancements in medical management, it remains high if compared with age-matched HIV-uninfected men, ranging from 13% to 40% in the age group of 20-60 years. Signs and symptoms of low serum testosterone (T) in MLWH are cause of concern since they are non-specific, of mild-to-moderate degree, and often overlapping with those of infection per se. For these reasons, hypogonadism can be underestimated in the absence of targeted laboratory blood examinations. With regard to the etiological factors involved in the T decrease, emerging evidence has suggested the functional nature of hypogonadism in MLWH, pointing out the mutual relationship between sex steroids, health status, comorbidities, and HIV-related factors. In agreement with this hypothesis, a therapeutic approach aiming at improving or reversing concomitant diseases through lifestyle changes (e.g. physical activity) rather than pharmacological T treatment should be theoretically considered. However, considering both patient's barriers to lifestyle changes to be maintained overtime and the lack of evidence-based data on the efficacy of lifestyle changes in normalizing serum T in MLWH, T therapy remains an option when other non-pharmacological interventions are ineffective as well as for all other functional forms of hypogonadism. From this perspective, the traditional therapeutic management of male hypogonadism in MLWH, especially the role of T supplementation, should be revised in the light of the probable functional nature of hypogonadism by considering a good balance between benefits and harmful. This narrative review presents an overview of current knowledge on hypogonadism in MLWH, deepening the factors driving and taking part in T decrease, providing advice for the clinical approach, and underlining the importance of individualized treatment aiming at optimizing non-gonadal comorbidities and thus avoiding over-, or even unnecessary, treatment with T.

Aging and androgens: Physiology and clinical implications

In men >  ~35 years, aging is associated with perturbations in the hypothalamus-pituitary-testicular axis and declining serum testosterone concentrations. The major changes are decreased gonadotropin-releasing hormone (GnRH) outflow and decreased Leydig cell responsivity to stimulation by luteinizing hormone (LH). These physiologic changes increase the prevalence of biochemical secondary hypogonadism-a low serum testosterone concentration without an elevated serum LH concentration. Obesity, medications such as opioids or corticosteroids, and systemic disease further reduce GnRH and LH secretion and might result in biochemical or clinical secondary hypogonadism. Biochemical secondary hypogonadism related to aging often remits with weight reduction and avoidance or treatment of other factors that suppress GnRH and LH secretion. Starting at age ~65-70, progressive Leydig cell dysfunction increases the prevalence of biochemical primary hypogonadism-a low serum testosterone concentration with an elevated serum LH concentration. Unlike biochemical secondary hypogonadism in older men, biochemical primary hypogonadism is generally irreversible. The evaluation of low serum testosterone concentrations in older men requires a careful assessment for symptoms, signs and causes of male hypogonadism. In older men with a body mass index (BMI) ≥ 30, biochemical secondary hypogonadism and without an identifiable cause of hypothalamus or pituitary pathology, weight reduction and improvement of overall health might reverse biochemical hypogonadism. For older men with biochemical primary hypogonadism, testosterone replacement therapy might be beneficial. Because aging is associated with decreased metabolism of testosterone and increased tissue-specific androgen sensitivity, lower dosages of testosterone replacement therapy are often effective and safer in older men.

Androgen Misuse and Abuse

Androgens are potent drugs requiring prescription for valid medical indications but are misused for invalid, unproven, or off-label reasons as well as being abused without prescription for illicit nonmedical application for performance or image enhancement. Following discovery and first clinical application of testosterone in the 1930s, commercialization of testosterone and synthetic androgens proliferated in the decades after World War II. It remains among the oldest marketed drugs in therapeutic use, yet after 8 decades of clinical use, the sole unequivocal indication for testosterone remains in replacement therapy for pathological hypogonadism, organic disorders of the male reproductive system. Nevertheless, wider claims assert unproven, unsafe, or implausible benefits for testosterone, mostly representing wishful thinking about rejuvenation. Over recent decades, this created an epidemic of testosterone misuse involving prescription as a revitalizing tonic for anti-aging, sexual dysfunction and/or obesity, where efficacy and safety remains unproven and doubtful. Androgen abuse originated during the Cold War as an epidemic of androgen doping among elite athletes for performance enhancement before the 1980s when it crossed over into the general community to become an endemic variant of drug abuse in sufficiently affluent communities that support an illicit drug industry geared to bodybuilding and aiming to create a hypermasculine body physique and image. This review focuses on the misuse of testosterone, defined as prescribing without valid clinical indications, and abuse of testosterone or synthetic androgens (androgen abuse), defined as the illicit use of androgens without prescription or valid indications, typically by athletes, bodybuilders and others for image-oriented, cosmetic, or occupational reasons.

Aging and sex hormones in males

Over the past two decades several large cohort studies have been performed to disclose the changes of sex hormone in elderly and their clinical significance. Beyond the decline of total testosterone, aging is accompanied by a sex hormone binding globulin (SHBG) increase, a steeper free testosterone decline, while gonadotropins may be increased or inappropriately normal, with important contribution of comorbidities (e.g., obesity) to these changes. Actually, it has become firm the concept that the biochemical finding of testosterone deficiency alone is not sufficient for diagnosing hypogonadism in older men. The definition of late-onset hypogonadism (LOH) includes low serum testosterone levels coupled with signs and symptoms related to hypogonadism. Indeed, the combination of multiple factors all contributing to the testosterone decline, with other concurrent comorbidities further overlapping, makes the clinical correlates of LOH highly heterogeneous. For all these reasons both the diagnosis and the therapeutic management of LOH, especially the decision about starting testosterone replacement treatment, remain challenging.

Testosterone recuperates deteriorated male fertility in cypermethrin intoxicated rats

The present study investigates the protective effects of testosterone against reproductive toxicity induced by cypermethrin (50 mg/kg body weight) in rats. Significant reduction in the testicular and accessory sex organ weights were observed in cypermethrin-treated rats over controls. Cypermethrin intoxication significantly reduced testicular daily sperm count, epididymal sperm count, sperm motility, sperm viability and HOS-tail coiled sperm accompanied by significant reduction in the activity levels of testicular steroidogenic enzymes such as 3β- and 17β- hydroxysteroid dehydrogenases in rats as compared to controls. Further, qPCR studies indicated that the mRNA expression levels of steroidogenic acute regulatory protein (StAR) significantly decreased in cypermethrin-treated rats over controls. Molecular docking analysis indicated that the binding affinity of cypermethrin (- 11.2 kcal/mol) towards StAR protein was greater as compared to its natural ligand, cholesterol (- 8.2 kcal/mol) suggesting improper cholesterol channeling across the testis. Significant reduction in the circulatory levels of testosterone was also recorded in cypermethrin-exposed rats. An increase in pre- and post-implantation loss was observed in rats cohabited with cypermethrin-treated rats. On the other hand, testosterone (4.16 mg/kg body weight) treatment ameliorated cypermethrin-induced reprotoxic effects in rats. To conclude, cypermethrin-induced deterioration of suppressed reproductive performance in male rats could be linked to its antiandrogenic effects and on the other hand, testosterone-mediated protection of male reproductive health in cypermethrin-treated rats at least in part occurs via restoration of testosterone biosynthesis, spermatogenesis and sperm maturation events.

Testosterone is not associated with traits of optimism or pessimism: Observational evidence from the prospective DETECT study

Background

Previous experimental research on testosterone (T) and psychological traits is inconclusive. Thus, we performed the first large-scale observational study of the association between T and dispositional optimism / pessimism.

Methods

We used prospective data from 6,493 primary-care patients (3,840 women) of the DETECT study (Diabetes Cardiovascular Risk-Evaluation: Targets and Essential Data for Commitment of Treatment), including repeated immunoassay-based measurement of serum T and optimism / pessimism assessed by the revised Life-Orientation Test (LOT-R). Cross-sectional and longitudinal associations of baseline T and one-year change in T with optimism and pessimism were investigated using age- and multivariable-adjusted regression models.

Results

Cross-sectional analyses showed no association of T with optimism or pessimism in both sexes. Longitudinal analyses also showed no association of baseline T with optimism or pessimism at four-year follow-up. Multivariable analyses of total LOT-R score yielded similarly non-significant results (β-coefficient per unit change in T for men: -0.01 (95% CI: -0.24–0.22), women: 0.08 (-0.03–0.20)). Furthermore, change in T was not related to optimism or pessimism at four-year follow-up.

Conclusions

The present observational study of a large-scale prospective sample showed no association of T with optimism or pessimism. Integrating further experimental and interventional evidence from alternative methodological approaches would strengthen this conclusion and establish stronger evidence about the potential hormonal basis of psychological traits.

Symptomatic androgen deficiency develops only when both total and free testosterone decline in obese men who may have incident biochemical secondary hypogonadism: Prospective results from the EMAS

OBJECTIVE

Limited evidence supports the use of free testosterone (FT) for diagnosing hypogonadism when sex hormone-binding globulin (SHBG) is altered. Low total testosterone (TT) is commonly encountered in obesity where SHBG is typically decreased. We aimed to assess the contribution of FT in improving the diagnosis of symptomatic secondary hypogonadism (SH), identified initially by low total testosterone (TT), and then further differentiated by normal FT (LNSH) or low FT (LLSH).

DESIGN

Prospective observational study with a median follow-up of 4.3 years.

PATIENTS

Three thousand three hundred sixty-nine community-dwelling men aged 40-79 years from eight European centres.

MEASUREMENTS

Subjects were categorized according to baseline and follow-up biochemical status into persistent eugonadal (referent group; n = 1880), incident LNSH (eugonadism to LNSH; n = 101) and incident LLSH (eugonadism to LLSH; n = 38). Predictors and clinical features associated with the transition from eugonadism to LNSH or LLSH were assessed.

RESULTS

The cumulative incidence of LNSH and LLSH over 4.3 years was 4.9% and 1.9%, respectively. Baseline obesity predicted both LNSH and LLSH, but the former occurred more frequently in younger men. LLSH, but not LNSH, was associated with new/worsened sexual symptoms, including low desire [OR = 2.67 (1.27-5.60)], erectile dysfunction [OR = 4.53 (2.05-10.01)] and infrequent morning erections [OR = 3.40 (1.48-7.84)].

CONCLUSIONS

These longitudinal data demonstrate the importance of FT in the diagnosis of hypogonadism in obese men with low TT and SHBG. The concurrent fall in TT and FT identifies the minority (27.3%) of men with hypogonadal symptoms, which were not present in the majority developing low TT with normal FT.

Elevated luteinizing hormone despite normal testosterone levels in older men-natural history, risk factors and clinical features

OBJECTIVE

Elevated luteinizing hormone (LH) with normal testosterone (T) suggests compensated dysregulation of the gonadal axis. We describe the natural history, risk factors and clinical parameters associated with the development of high LH (HLH, LH >9.4 U/L) in ageing men with normal T (T ≥ 10.5 nmol/L).

DESIGN, PATIENTS AND MEASUREMENTS

We conducted a 4.3-year prospective observational study of 3369 community-dwelling European men aged 40-79 years. Participants were classified as follows: incident (i) HLH (n = 101, 5.2%); persistent (p) HLH (n = 128, 6.6%); reverted (r) HLH (n = 46, 2.4%); or persistent normal LH (pNLH, n = 1667, 85.8%). Potential predictors and changes in clinical features associated with iHLH and rHLH were analysed using regression models.

RESULTS

Age >70 years (OR = 4.12 [2.07-8.20]), diabetes (OR = 2.86 [1.42-5.77]), chronic pain (OR = 2.53 [1.34-4.77]), predegree education (OR = 1.79 [1.01-3.20]) and low physical activity (PASE ≤ 78, OR = 2.37 [1.24-4.50]) predicted development of HLH. Younger age (40-49 years, OR = 8.14 [1.35-49.13]) and nonsmoking (OR = 5.39 [1.48-19.65]) predicted recovery from HLH. Men with iHLH developed erectile dysfunction, poor health, cardiovascular disease (CVD) and cancer more frequently than pNLH men. In pHLH men, comorbidities, including CVD, developed more frequently, and cognitive and physical function deteriorated more, than in pNLH men. Men with HLH developed primary hypogonadism more frequently (OR = 15.97 [5.85-43.60]) than NLH men. Men with rHLH experienced a small rise in BMI.

CONCLUSIONS

Elevation of LH with normal T is predicted by multiple factors, reverts frequently and is not associated with unequivocal evidence of androgen deficiency. High LH is a biomarker for deteriorating health in aged men who tend to develop primary hypogonadism.

Aging and sex hormones in males

Several large cohort studies have disclosed the trajectories of sex steroids changes overtime in men and their clinical significance. In men the slow, physiological decline of serum testosterone (T) with advancing age overlaps with the clinical condition of overt, pathological hypogonadism. In addition, the increasing number of comorbidities, together with the high prevalence of chronic diseases, all further contribute to the decrease of serum T concentrations in the aging male. For all these reasons both the diagnosis of late-onset hypogonadism (LOH) in men and the decision about starting or not T replacement treatment remain challenging. At present, the biochemical finding of T deficiency alone is not sufficient for diagnosing hypogonadism in older men. Coupling hypogonadal symptoms with documented low serum T represents the best strategy to refine the diagnosis of hypogonadism in older men and to avoid unnecessary treatments.

A Perspective on Middle-Aged and Older Men With Functional Hypogonadism: Focus on Holistic Management

CONTEXT

Middle-aged and older men (≥50 years), especially those who are obese and suffer from comorbidities, not uncommonly present with clinical features consistent with androgen deficiency and modestly reduced testosterone levels. Commonly, such men do not demonstrate anatomical hypothalamic-pituitary-testicular axis pathology but have functional hypogonadism that is potentially reversible.

EVIDENCE ACQUISITION

Literature review from 1970 to October 2016.

EVIDENCE SYNTHESIS

Although definitive randomized controlled trials are lacking, evidence suggests that in such men, lifestyle measures to achieve weight loss and optimization of comorbidities, including discontinuation of offending medications, lead to clinical improvement and a modest increase in testosterone. Also, androgen deficiency-like symptoms and end-organ deficits respond to targeted treatments (such as phosphodiesterase-5 inhibitors for erectile dysfunction) without evidence that hypogonadal men are refractory. Unfortunately, lifestyle interventions remain difficult and may be insufficient even if successful. Testosterone therapy should be considered primarily for men who have significant clinical features of androgen deficiency and unequivocally low testosterone levels. Testosterone should be initiated either concomitantly with a trial of lifestyle measures, or after such a trial fails, after a tailored diagnostic work-up, exclusion of contraindications, and appropriate counseling.

CONCLUSIONS

There is modest evidence that functional hypogonadism responds to lifestyle measures and optimization of comorbidities. If achievable, these interventions may have demonstrable health benefits beyond the potential for increasing testosterone levels. Therefore, treatment of underlying causes of functional hypogonadism and of symptoms should be used either as an initial or adjunctive approach to testosterone therapy.

Natural history, risk factors and clinical features of primary hypogonadism in ageing men: Longitudinal Data from the European Male Ageing Study

OBJECTIVE

In ageing men, the incidence and clinical significance of testosterone (T) decline accompanied by elevated luteinizing hormone (LH) are unclear. We describe the natural history, risk factors and clinical features associated with the development of biochemical primary hypogonadism (PHG, T < 10·5 nmol/l and LH>9·4U/l) in ageing men.

DESIGN, PATIENTS AND MEASUREMENTS

A prospective observational cohort survey of 3,369 community-dwelling men aged 40-79 years, followed up for 4·3 years. Men were classified as incident (i) PHG (eugonadal [EUG, T ≥ 10·5 nmol/l] at baseline, PHG at follow-up), persistent (p) PHG (PHG at baseline and follow-up), pEUG (EUG at baseline and follow-up) and reversed (r) PHG (PHG at baseline, EUG at follow-up). Predictors and changes in clinical features associated with the development of PHG were analysed by regression models.

RESULTS

Of 1,991 men comprising the analytical sample, 97·5% had pEUG, 1·1% iPHG, 1·1% pPHG and 0·3% rPHG. The incidence of PHG was 0·2%/year. Higher age (>70 years) [OR 12·48 (1·27-122·13), P = 0·030] and chronic illnesses [OR 4·24 (1·08-16·56); P = 0·038] predicted iPHG. Upon transition from EUG to PHG, erectile function, physical vigour and haemoglobin worsened significantly. Men with pPHG had decreased morning erections, sexual thoughts and haemoglobin with increased insulin resistance.

CONCLUSIONS

Primary testicular failure in men is uncommon and predicted by old age and chronic illness. Some clinical features attributable to androgen deficiency, but not others, accompanied the T decline in men who developed biochemical PHG. Whether androgen replacement can improve sexual and/or physical function in elderly men with PHG merits further study.

The effects of visceral obesity and androgens on bone: trenbolone protects against loss of femoral bone mineral density and structural strength in viscerally obese and testosterone-deficient male rats

SUMMARY

In males, visceral obesity and androgen deficiency often present together and result in harmful effects on bone. Our findings show that both factors are independently associated with adverse effects on femoral bone structure and strength, and trenbolone protects rats from diet-induced visceral obesity and consequently normalises femoral bone structural strength.

INTRODUCTION

In light of the rapidly increasing incidence of obesity and osteoporosis globally, and recent conjecture regarding the effects of visceral adiposity and testosterone deficiency on bone health, we investigated the effects of increased visceral adipose tissue (VAT) mass on femoral bone mineral density (BMD), structure and strength in normal weight rats with testosterone deficiency.

METHODS

Male Wistar rats (n = 50) were fed either standard rat chow (CTRL, n = 10) or a high-fat/high-sugar diet (HF/HS, n = 40). Following 8 weeks of feeding, rats underwent sham surgery (CTRL, n = 10; HF/HS, n = 10) or orchiectomy (HF/HS + ORX, n = 30). Following a 4-week recovery period, mini-osmotic pumps containing either vehicle (CTRL, n = 10; HF/HS, n = 10; HF/HS + ORX, n = 10), 2.0 mg kg day(-1), testosterone (HF/HS + ORX + TEST, n = 10) or 2.0 mg kg day(-1) trenbolone (HF/HS + ORX + TREN, n = 10) were implanted for 8 weeks of treatment. Dual-energy X-ray absorptiometry and three-point bending tests were used to assess bone mass, structure and strength of femora.

RESULTS

Diet-induced visceral obesity resulted in decreased bone mineral area (BMA) and content (BMC) and impaired femoral stiffness and strength. Orchiectomy further impaired BMA, BMC and BMD and reduced energy to failure in viscerally obese animals. Both TEST and TREN treatment restored BMA, BMC, BMD and energy to failure. Only TREN reduced visceral adiposity and improved femoral stiffness and strength.

CONCLUSIONS

Findings support a role for both visceral adiposity and testosterone deficiency as independent risk factors for femoral osteoporosis, adverse bone geometry and impaired bone strength in male rats. Trenbolone may be a more effective candidate for androgen replacement therapy than testosterone in viscerally obese testosterone-deficient males.

Modification Effects of Changes in Job Demands on Associations Between Changes in Testosterone Levels and Andropause Symptoms: 2-Year Follow-up Study in Male Middle-Aged Japanese Workers

PURPOSE

The purpose of this longitudinal study was to ascertain if changes in job demands modify associations between changes in testosterone levels and andropause symptoms in male Japanese workers.

METHOD

A baseline survey including job demands and the Aging Males' Symptoms scale, lifestyle factors, and blood levels of testosterone was conducted in 2007. Among 192 men (mean age ± SD 52.2 ± 7.6 years) who completed all relevant questionnaires and provided blood at baseline, 104 men (50.9 ± 7.2 years) were followed up in 2009. Changes of variables in 2 years were calculated (data of follow-up minus those of baseline).

RESULTS

Testosterone levels were increased significantly, whereas job demands and somatic symptoms were reduced significantly, at follow-up. Changes in testosterone levels were negatively associated with changes in total andropause symptoms, psychological symptoms, and sexual symptoms (standardized β = -0.27, -0.24, and, -0.29, p < 0.05, respectively), after adjustment for confounders. Changes in job demands were positively associated with changes in somatic symptoms (standardized β = 0.21, p < 0.05). Significant interactions of changes in testosterone levels and job demands were noted for changes in psychological symptoms (standardized β = 0.26, p < 0.05). For men with a 1-SD reduction in job demands, negative associations between changes in testosterone levels and psychological symptoms were intensified, but not for men with a 1-SD increase in job demands.

CONCLUSION

Andropause symptoms may be affected by changes in testosterone levels and job demands. Change in job demands may modify associations between changes in testosterone levels and andropause symptoms.

Estimating age-specific trends in circulating testosterone and sex hormone-binding globulin in males and females across the lifespan

BACKGROUND

Age-specific trends of serum testosterone and sex hormone-binding globulin across the full lifespan have not been reported.

METHODS

We deduced age-specific trends in serum testosterone and sex hormone-binding globulin in males and females between ages 10 and 90 from a large sample of consecutive results from a single large pathology laboratory. Coded results of 110,712 consecutive blood samples requesting serum testosterone over seven years (2007-2013) comprising blood testosterone, sex hormone-binding globulin and calculated free testosterone together with gender and age were analysed create smoothed age-specific centiles (2.5%, 5%, 25%, 50%, 75%, 95%, 97.5%) for males and females.

RESULTS

These identified the pubertal increases in serum testosterone in males peaking at 20 years of age and remaining stable thereafter until the eighth decade. In females, circulating testosterone peaked in late adolescence and declined gradually over the next two decades but remained stable across menopause and beyond. After early childhood, serum sex hormone-binding globulin declines to a nadir in males at the age of 20 years and remains stable till the sixth decade with a gradual, progressive rise thereafter. In females, the sex hormone-binding globulin nadir is reached earlier with levels rising gradually and progressively with age thereafter and accelerating after the age of 70 years. Females also exhibit a second sex hormone-binding globulin peak during reproductive ages reflected only in upper centiles due to effects of pregnancy and oral contraceptive use in a significant minority of females.

CONCLUSIONS

This large sample of clinical data provides a comprehensive profile of androgen status across the lifespan from early adolescence to late old age.

Impact of Diet-Induced Obesity and Testosterone Deficiency on the Cardiovascular System: A Novel Rodent Model Representative of Males with Testosterone-Deficient Metabolic Syndrome (TDMetS)

INTRODUCTION

Current models of obesity utilise normogonadic animals and neglect the strong relationships between obesity-associated metabolic syndrome (MetS) and male testosterone deficiency (TD). The joint presentation of these conditions has complex implications for the cardiovascular system that are not well understood. We have characterised and investigated three models in male rats: one of diet-induced obesity with the MetS; a second using orchiectomised rats mimicking TD; and a third combining MetS with TD which we propose is representative of males with testosterone deficiency and the metabolic syndrome (TDMetS).

METHODS

Male Wistar rats (n = 24) were randomly assigned to two groups and provided ad libitum access to normal rat chow (CTRL) or a high fat/high sugar/low protein "obesogenic" diet (OGD) for 28 weeks (n = 12/group). These groups were further sub-divided into sham-operated or orchiectomised (ORX) animals to mimic hypogonadism, with and without diet-induced obesity (n = 6/group). Serum lipids, glucose, insulin and sex hormone concentrations were determined. Body composition, cardiovascular structure and function; and myocardial tolerance to ischemia-reperfusion were assessed.

RESULTS

OGD-fed animals had 72% greater fat mass; 2.4-fold greater serum cholesterol; 2.3-fold greater serum triglycerides and 3-fold greater fasting glucose (indicative of diabetes mellitus) compared to CTRLs (all p<0.05). The ORX animals had reduced serum testosterone and left ventricle mass (p<0.05). In addition to the combined differences observed in each of the isolated models, the OGD, ORX and OGD+ORX models each had greater CK-MB levels following in vivo cardiac ischemia-reperfusion insult compared to CTRLs (p<0.05).

CONCLUSION

Our findings provide evidence to support that the MetS and TD independently impair myocardial tolerance to ischemia-reperfusion. The combined OGD+ORX phenotype described in this study is a novel animal model with associated cardiovascular risk factors and complex myocardial pathology which may be representative of male patients presenting with TDMetS.

Sex steroids levels in chronic kidney disease and kidney transplant recipients: associations with disease severity and prediction of mortality

OBJECTIVE

Our objective was to characterize and evaluate prognostic implications of circulating sex steroids in patients at different stages of chronic kidney disease (CKD).

DESIGN

Prospective observational cohort study.

PATIENTS

We prospectively recruited patients with CKD III-IV, undergoing chronic dialysis and kidney transplant recipients (KTR) from a single centre in 2003-2004.

MEASUREMENTS

Two stored samples taken 3 months apart were analysed for sex hormones using liquid chromatography/tandem mass spectrometry, and the mean of the two was used for analysis. We also measured novel biomarkers troponin T and NT-proBNP. Patients were followed until death, transplant or 30 June 2013, and survival analysis performed.

RESULTS

In males, but not in females, both testosterone (P = 0·003) as well as oestradiol (P < 0·02) levels were lowest in dialysis patients and highest in KTR. Over a median follow up of 8·5 years (interquartile range 3·8-9·2), 52 men (36%) died and 24 (17%) received a kidney transplant. In Cox proportional hazards regression up to 9·6 years, an increase in total testosterone of 1 nmol/l was associated with a 9·8% (95% confidence interval 3·1-16·3) decrease in mortality independent of age, body mass index, stage of renal disease and circulating levels of NT-proBNP or troponin T. By contrast, sex steroid levels were not associated with mortality in females.

CONCLUSIONS

Testosterone levels differ across stages of kidney disease and low testosterone levels predict mortality in males, independent of established and novel predictors of mortality.

New horizons in testosterone and the ageing male

The fall in testosterone levels with age appears to be a real phenomenon. Declining testicular function and hypothalamic dysregulation appear to be the mechanisms explaining the fall in testosterone levels with age. The increased prevalence of obesity and chronic illness in ageing men both cause a large drop in testosterone levels independent of ageing. Age-related hypogonadism appears to be different to other 'classical' causes of hypogonadism. Testosterone levels are not unequivocally low and associated symptoms are non-specific. In frail older men with low testosterone levels, testosterone therapy appears to improve QOL and physical function. In less frail men, however, effects of testosterone therapy in the ageing male are small and/or inconsistent. There remains an urgent need for randomised clinical trials with sufficient size, duration and power to determine specific benefits and risks of testosterone therapy in older men.

Late-onset hypogonadism: current concepts and controversies of pathogenesis, diagnosis and treatment

Although suppressed serum testosterone (T) is common in ageing men, only a small proportion of them develop the genuine syndrome of low T associated with diffuse sexual (e.g., erectile dysfunction), physical (e.g. loss of vigor and frailty) and psychological (e.g., depression) symptoms. This syndrome carries many names, including male menopause or climacterium, andropause and partial androgen deficiency of the ageing male (PADAM). Late-onset hypogonadism (LOH) describes it best and is therefore generally preferred. The decrease of T in LOH is often marginal, and hypogonadism can be either due to primary testicular failure (low T, high luteinizing hormone (LH)) or secondary to a hypothalamic-pituitary failure (low T, low or inappropriately normal LH). The latter form is more common and it is usually associated with overweight/obesity or chronic diseases (e.g., type 2 diabetes mellitus, the metabolic syndrome, cardiovascular and chronic obstructive pulmonary disease, and frailty). A problem with the diagnosis of LOH is that often the symptoms (in 20%–40% of unselected men) and low circulating T (in 20% of men >70 years of age) do not coincide in the same individual. The European Male Ageing Study (EMAS) has recently defined the strict diagnostic criteria for LOH to include the simultaneous presence of reproducibly low serum T (total T <11 nmol l⁻¹ and free T <220 pmol l⁻¹) and three sexual symptoms (erectile dysfunction, and reduced frequency of sexual thoughts and morning erections). By these criteria, only 2% of 40- to 80-year-old men have LOH. In particular obesity, but also impaired general health, are more common causes of low T than chronological age per se. Evidence-based information whether, and how, LOH should be treated is sparse. The most logical approach is lifestyle modification, weight reduction and good treatment of comorbid diseases. T replacement is widely used for the treatment, but evidence-based information about its real benefits and short- and long-term risks, is not yet available. In this review, we will summarize the current concepts and controversies in the pathogenesis, diagnosis and treatment of LOH.

The implications of low testosterone on mortality in men

Testosterone levels in men slowly decline with aging and also decline more abruptly due to medical illness or medications. Prescriptions for testosterone have increased dramatically over the past decade, since a testosterone-gel formulation was approved and since numerous studies reported an association between low serum testosterone and increased mortality. However, recent observational studies of testosterone treatment have reported conflicting results with some studies reporting decreased risks for mortality while others reported increased mortality risks with testosterone treatment. This paper will summarize recent studies of low serum testosterone and mortality and testosterone treatment and mortality and what the potential implications of these studies are for the clinician.

Testosterone levels increase in association with recovery from acute fracture in men

In this longitudinal case-control study, acute fracture was associated with low serum testosterone, which was transient in 43% of men. While assessment of gonadal status is part of the assessment of bone fragility, measurement of testosterone in the early period after fracture may overestimate the prevalence of androgen deficiency.

INTRODUCTION

Measurement of circulating testosterone is recommended in the evaluation of bone fragility in men. Since acute illness can transiently decrease circulating testosterone, we quantified the association of acute fracture and serum testosterone levels.

METHODS

A case-control study was conducted involving 240 men with a radiologically confirmed minimal trauma fracture presenting to a tertiary referral hospital and 89 age-matched men without a history of minimal trauma fracture serving as controls. Follow-up testosterone levels 6 months after baseline were available for 98 cases and 27 controls. Results were expressed as the median and interquartile (IQR) range.

RESULTS

Compared to controls, cases had lower total testosterone [TT, 7.2 (3.5, 10.8) vs 13.6 (10.9, 17.1) nmol/L, p < 0.001]. The 143 cases treated as inpatients had lower testosterone levels than the 97 cases treated as outpatients [TT 4.7 (2.3, 8.1) vs 10.3 (7.5, 12.7) nmol/L, p < 0.001]. Group differences in calculated free testosterone (cFT) were comparable to the group differences in TT. At follow-up, in 98 cases, median TT increased from 6.5 nmol/L (3.2, 8.5) to 9.6 nmol/L (6.9, 12.0) p < 0.0001, and SHBG remained unchanged. Of cases with low testosterone, 43% with TT <10 nmol/L and/or cFT <230 pmol/L at presentation were reclassified as androgen sufficient at follow-up. TT was unchanged in the controls.

CONCLUSIONS

Low testosterone levels in men presenting with an acute fracture may, at least in part, be due to an acute, fracture-associated, stress response. To avoid over diagnosis, evaluation for testosterone deficiency should be deferred until recovery from the acute event.

Systematic Literature Review of the Epidemiology of Nongenetic Forms of Hypogonadism in Adult Males

This study summarizes the literature on the prevalence, incidence, and proportion of patients receiving treatment for male hypogonadism and a systematic literature search was performed for articles published in the last 20 years. Of the 97 studies identified, 96 examined the prevalence, 2 examined the incidence, and 4 examined the proportion of males with hypogonadism patients receiving treatment. Based on studies conducted in Europe and USA, the prevalence of hypogonadism in the general population ranged from 2.1% to 12.8% of middle-aged to older men, with an estimated incidence of 12 new cases per 1,000 person-years. Prevalence was higher among patients with comorbid conditions, such as type 2 diabetes mellitus and obesity. Approximately 10–12% of men with hypogonadism were receiving testosterone treatment. This literature review suggests that there is potentially a significant burden of hypogonadism in the general population. Burden seems to increase with age and in the presence of certain disease conditions. Data suggests that many hypogonadal men who may benefit from testosterone replacement are not receiving treatment. This may be the result of underdiagnosis of the disease, lack of awareness by patients or physicians, irregularities surrounding the diagnostic criteria, and deficiency of long-term safety studies.

A 6-month observational study of energy, sexual desire, and body proportions in hypogonadal men treated with a testosterone 1% gel

AIMS AND METHODS

This was a 6-month, open label, multinational, observational study in hypogonadal men treated with daily titrated dose of 50, 75, or 100 mg 1% testosterone gel (AndroGel®) in community practice. Primary outcome was effect of treatment on hypogonadal symptoms and quality of life as assessed by Aging Males' Symptoms (AMS) scale. Secondary objectives included erectile dysfunction (International Index of Erectile Function [IIEF]), fatigue (Multidimensional Fatigue Inventory [MFI]), and surrogates for body composition (waist circumference, body mass index [BMI]).

RESULTS

Seven hundred and ninety-nine of the 1053 men enrolled had follow-up data at 6 months, 81.2% had ≥1 testosterone value in the normal range during the study. Substantial and significant improvements were observed in mean AMS score (-29%), IIEF score (+115.7%), and MFI scores (-21.5%). Further beneficial effects were significant decreases in mean BMI (-0.8 kg/m(2)) and waist circumference (-3.3 cm). Younger age quartiles showed greater improvements in AMS, MFI, BMI, and waist circumference than older quartiles. IIEF scores, however, did not differ significantly by age category.

CONCLUSIONS

Substantial improvements in hypogonadal symptoms, quality of life, fatigue, erectile dysfunction, and libido/sexual desire were observed. Adverse drug reactions were experienced by 7.5% of the safety population over the 6-month study period.

Testosterone and glucose metabolism in men: current concepts and controversies

A wealth of observational studies show that low testosterone is associated with insulin resistance and with an increased risk of diabetes and the metabolic syndrome. Experimental studies have identified potential mechanisms by which low testosterone may lead to insulin resistance. Visceral adipose tissue is an important intermediate in this relationship. Actions of testosterone or its metabolite oestradiol on other tissues such as muscle, liver, bone or the brain, and body composition-independent effects may also play a role. However, definitive evidence from randomised controlled trials (RCTs) to clarify whether the association of low testosterone with disordered glucose metabolism is causative is currently lacking. It therefore remains possible that this association is due to reverse causation, or simply originates by association with common health and lifestyle factors. RCTs of testosterone therapy in men with or without diabetes consistently show modest metabolically favourable changes in body composition. Despite this, testosterone effects on glucose metabolism have been inconsistent. Recent evidence suggests that the hypothalamic-pituitary-testicular axis suppression in the majority of obese men with metabolic disorders is functional, and may be, at least in part, reversible with weight loss. Until further evidence is available, lifestyle measures with emphasis on weight reduction, treatment of comorbidities and optimisation of diabetic control should remain the first-line treatment in these men. Such measures, if successful, may be sufficient to normalise testosterone levels in men with metabolic disorders, who typically have only modest reductions in circulating testosterone levels.

Testosterone and mood in aging men

Age-associated hypothalamic-pituitary-gonadal (HPG) axis hypofunction, or partial androgen deficiency of the aging male, is thought to be responsible for various age-associated conditions such as reduced muscle and bone mass, mobility limitations, frailty, obesity, sleep apnea, cognitive impairment, sexual dysfunction, and depression. It has been difficult to establish consistent correlations between these symptoms and plasma testosterone levels in middle-aged men, but testosterone replacement does lead to improved muscle strength, bone density, and sexual function. This article focuses on the relationship between testosterone and mood in older men, and the treatment of age-related depression with exogenous testosterone.

Serum testosterone, dihydrotestosterone and estradiol concentrations in older men self-reporting very good health: the healthy man study

OBJECTIVE

To determine serum concentrations, intra-individual variability and impact of age-related co-morbidities on serum testosterone (T), dihydrotestosterone (DHT), estradiol (E(2)) and estrone (E(1)) in older men.

DESIGN

Observational, repeated measures study.

PARTICIPANTS

Men (n = 325) with 40 years and older self-reporting very good or excellent health.

MEASUREMENTS

Standardized history, physical examination and collection of nine blood samples at fixed time intervals were measured over 3 months (three at 20 min intervals on days 1 (fasting) and 2 (non-fasting), one at days 7, 30 and 90). Serum T, DHT, E(2) and E(1) (n = 2900, > 99% of scheduled samples) measured by liquid chromatography-tandem mass spectrometry (LC-MS) were analysed by linear mixed model analysis with fasting, age and obesity as covariables.

RESULTS

Mean serum T did not vary with age (P = 0·76) but obesity (-0·35 nM per body mass index (BMI) unit, P < 0·0001) and ex-smoker status (-1·6 nM, P < 0·001) had significant effects. Serum DHT was increased with age (+0·011 nM per year, P = 0·001) but decreased with obesity (-0·05 nM per BMI unit, P < 0·0001). Serum E(2) did not vary with age (P = 0·31) or obesity (P = 0·12). Overnight fasting increased (by 9-16%, all P < 0·001) and reduced variability in morning serum T, DHT, E(2) and E(1). Non-fasting serum T and DHT were stable over time (day, week, month or 3 months; P > 0·28).

CONCLUSIONS

Serum T, DHT and E(2) displayed no decrease associated with age among men over 40 years of age who self-report very good or excellent health although obesity and ex-smoking status were associated with decreased serum androgens (T and DHT) but not E(2). These findings support the interpretation that the age-related decline in blood T accompanying non-specific symptoms in older men may be due to accumulating age-related co-morbidities rather than a symptomatic androgen deficiency state.

Andropause and the development of cardiovascular disease presentation-more than an epi-phenomenon

Andropause refers to a generalized decline of male hormones, including testosterone and dehydroepiandrosterone in middle-aged and aging men. This decline in hormones has been associated with changes such as depression, loss of libido, sexual dysfunction, and changes in body composition. Aging has been associated with an abundance of concomitant diseases, in particular cardiovascular diseases, and although andropause is correlated to aging, a causal relationship between reduction of androgens and the development of chronic diseases such as atherosclerosis and heart failure has not been convincingly established yet. On the other hand, increasing data has emerged that revealed the effects of low levels of androgens on cardiovascular disease progression. As an example, low levels of testosterone have been linked to a higher incidence of coronary artery disease. Whether hormone replacement therapy that is used for andropausal men to alleviate symptoms of "male menopause" can halt progression of cardiovascular disease, remains controversially discussed, primarily due to the lack of well-designed, randomized controlled trials. At least for symptom improvement, the use of androgen replacement therapy in andropausal men may be clinically indicated, and with the appropriate supervision and follow up may prove to be beneficial with regard to preservation of the integrity of cardiovascular health at higher ages.

Reference ranges for testosterone in men generated using liquid chromatography tandem mass spectrometry in a community-based sample of healthy nonobese young men in the Framingham Heart Study and applied to three geographically distinct cohorts

CONTEXT

Reference ranges are essential for partitioning testosterone levels into low or normal and making the diagnosis of androgen deficiency. We established reference ranges for total testosterone (TT) and free testosterone (FT) in a community-based sample of men.

METHODS

TT was measured using liquid chromatography tandem mass spectrometry in nonobese healthy men, 19-40 yr old, in the Framingham Heart Study Generation 3; FT was calculated. Values below the 2.5th percentile of reference sample were deemed low. We determined the association of low TT and FT with physical dysfunction, sexual symptoms [European Male Aging Study (EMAS) only], and diabetes mellitus in three cohorts: Framingham Heart Study generations 2 and 3, EMAS, and the Osteoporotic Fractures in Men Study.

RESULTS

In a reference sample of 456 men, mean (sd), median (quartile), and 2.5th percentile values were 723.8 (221.1), 698.7 (296.5), and 348.3 ng/dl for TT and 141. 8 (45.0), 134.0 (60.0), and 70.0 pg/ml for FT, respectively. In all three samples, men with low TT and FT were more likely to have slow walking speed, difficulty climbing stairs, or frailty and diabetes than those with normal levels. In EMAS, men with low TT and FT were more likely to report sexual symptoms than men with normal levels. Men with low TT and FT were more likely to have at least one of the following: sexual symptoms (EMAS only), physical dysfunction, or diabetes.

CONCLUSION

Reference ranges generated in a community-based sample of men provide a rational basis for categorizing testosterone levels as low or normal. Men with low TT or FT by these criteria had higher prevalence of physical dysfunction, sexual dysfunction, and diabetes. These reference limits should be validated prospectively in relation to incident outcomes and in randomized trials.

Late-onset hypogonadism

Late-onset hypogonadism is a clinical and biological syndrome associated with advancing age and characterized by typical symptoms and a deficiency in serum testosterone levels. It is a common condition but often underdiagnosed and undertreated. The main symptoms of hypogonadism are reduced libido/erectile dysfunction, reduced muscle mass and strength, increased adiposity, osteoporosis/low bone mass, depressed mood, and fatigue. Testosterone replacement therapy is only warranted in the presence of both clinical symptoms suggesting hormone deficiency and decreased hormone levels. It improves libido and sexual function, bone density, muscle mass, body composition, mood, erythropoiesis, cognition, quality of life, and cardiovascular disease.

Male late-onset hypogonadism: pathogenesis, diagnosis and treatment

Some aging men develop a condition of suppressed serum testosterone levels, which is associated with diffuse sexual, physical and psychological symptoms. Several terms are used for this syndrome, but late-onset hypogonadism (LOH) is preferred. The diagnosis of LOH is often uncertain because symptoms (occurring in 20-40% of men) and low circulating testosterone (found in 20% of men >70 years of age) seldom occur together. The strict diagnostic criteria for LOH include reproducibly low serum testosterone levels and sexual symptoms, including erectile dysfunction and reduced frequency of sexual thoughts and morning erections. Using these diagnostic criteria, only 2% of 40-80-year-old men have LOH. Obesity and impaired general health (including diabetes mellitus, cardiovascular and chronic obstructive pulmonary disease, and frailty) are more common reasons for low testosterone than advanced age per se. It seems logical, therefore, to begin by treating these conditions before testosterone replacement therapy is initiated. Even then, testosterone should only be used if there are no contraindications, such as unstable cardiac disease, serious prostate symptoms and high hemoglobin level. The long-term benefit of testosterone replacement therapy is uncertain, and the experimental nature of the treatment, and its associated risks, must be fully explained to the patient before treatment begins.

A practical guide to male hypogonadism in the primary care setting

There is a high prevalence of hypogonadism in the older adult male population and the proportion of older men in the population is projected to rise in the future. As hypogonadism increases with age and is significantly associated with various comorbidities such as obesity, type 2 diabetes, hypertension, osteoporosis and metabolic syndrome, the physician is increasingly likely to have to treat hypogonadism in the clinic. The main symptoms of hypogonadism are reduced libido/erectile dysfunction, reduced muscle mass and strength, increased adiposity, osteoporosis/low bone mass, depressed mood and fatigue. Diagnosis of the condition requires the presence of low serum testosterone levels and the presence of hypogonadal symptoms. There are a number of formulations available for testosterone therapy including intramuscular injections, transdermal patches, transdermal gels, buccal patches and subcutaneous pellets. These are efficacious in establishing eugonadal testosterone levels in the blood and relieving symptoms. Restoration of testosterone levels to the normal range improves libido, sexual function, and mood; reduces fat body mass; increases lean body mass; and improves bone mineral density. Testosterone treatment is contraindicated in subjects with prostate cancer or benign prostate hyperplasia and risks of treatment are perceived to be high by many physicians. These risks, however, are often exaggerated and should not outweigh the benefits of testosterone treatment.

Temporal trends in testosterone levels and treatment in older men

PURPOSE OF REVIEW

Longitudinal studies of testosterone concentrations have yielded sharper estimates of age-related androgen declines than their cross-sectional counterparts. A potential explanation for this phenomenon is a secular (age independent) mechanism acting to accelerate within-individual testosterone decreases with time. This article reviews the evidence in favor of such secular trends and discusses potential causes and implications.

RECENT FINDINGS

The magnitude of the proposed secular trend may be as much as 1% per calendar year in excess of per year cross-sectional trends. Current evidence suggests that body composition changes as expressed by BMI can in part account for the trend in testosterone. More speculative recent findings suggest a potential contributory role for environmental endocrine disruptors, but to date no longitudinal studies have examined this question. Symptomatic androgen deficiency as currently defined is associated with diverse downstream morbidity, but may not constitute a robust designation over longer term periods of time. Information concerning treatment patterns in the general population is limited.

SUMMARY

Existing evidence, though limited, supports the hypothesis of secular declines in serum testosterone levels in adult men. It is conceivable that these trends may influence the health of the public. Studies confirming and accounting for these trends are needed.

Time for international action on treating testosterone deficiency syndrome

AIM

Testosterone deficiency is having an increasing impact on men's health because of global aging, higher levels of obesity, diabetes and metabolic syndrome and adverse environmental factors such as stress xenoestrogens and anti-androgens. The question addressed is to what extent the large body of evidence on the benefits and safety of testosterone therapy is applied in clinical practice.

METHODS

Demographic data for men over the age of 50 from different regions of the world have been compared with the number of men in that age group estimated from sales figures to be receiving testosterone treatment.

RESULTS

On the basis of estimate that 20% of men over 50 in the general population of each region could be expected to have testosterone deficiency symptoms, on average only these men (0.69%) in most European countries were receiving treatment. Proportion was higher in the UK (1.00%) and Germany (1.89%), but lower in France (0.49%), Italy (0.51%) and Russia (0.54%). Interestingly, Australia had higher figures (1.64%), in spite of tight state control measures on androgen use. The USA has the highest treatment rate (7.96%) and this is increasing rapidly. If the basis for the diagnosis was the more conventional combination of symptoms plus biochemical evidence of low total and free testosterone levels, androgen deficiency would be expected in at least 5% of men over 50, and percentage treatment rates therefore four times higher. However, even on that basis, only in the USA do these exceed 10%.

CONCLUSIONS

International action is urgently needed to raise awareness in the medical profession in the various countries of these remarkably low levels of testosterone treatment. Improvement in this requires education and motivation of doctors and those regulating the healthcare systems. A public awareness campaign is needed to educate men about the symptoms of testosterone deficiency and its impact on their health.

The prevalence of and risk factors for androgen deficiency in aging Taiwanese men

INTRODUCTION

Androgen deficiency in aging men has attracted much medical interest. Most studies on androgen deficiency have been conducted in Caucasian populations, and data from other ethnicities are lacking.

AIM

To evaluate the prevalence of and risk factors for androgen deficiency and symptomatic androgen deficiency in Taiwanese men over 40 years old.

METHODS

From August 2007 to April 2008, a free health screening was conducted by a medical center in Kaohsiung, Taiwan, and 819 men participated in this health screening. All participants completed a health questionnaire, received a detailed physical examination, and blood samples were drawn between 8:00 and 12:00 am.

MAIN OUTCOME MEASURES

Serum total testosterone (TT), albumin, and sex hormone-binding globulin levels were measured. The level of free testosterone (FT) was calculated. Clinical symptoms of androgen deficiency were assessed using the Androgen Deficiency in the Aging Male (ADAM) questionnaire.

RESULTS

Seven hundred thirty-four men who met the inclusion criteria (mean age 57.4 +/- 6.7 years; range: 43-87 years) were included in this study. The prevalence of androgen deficiency was 24.1% based on the criterion of TT level < 300 ng/dL, and 16.6% based on the criterion of both TT < 300 ng/dL and FT < 5 ng/dL. The prevalence of symptomatic androgen deficiency was 12.0%. Both prevalence of androgen deficiency and symptomatic androgen deficiency increased with age. Older age, obesity, and diabetes mellitus were independent risk factors for androgen deficiency and symptomatic androgen deficiency.

CONCLUSIONS

In a sample of aging Taiwanese men, a substantial proportion had androgen deficiency and symptomatic androgen deficiency, and the prevalence increased with age. Older age, obesity, and diabetes mellitus were independent risk factors for androgen deficiency and symptomatic androgen deficiency. Those potentially modifiable risk factors like obesity and diabetes mellitus should be prevented to maintain normal testosterone levels during aging in men.