Androgen supplementation in eugonadal men with osteoporosis-effects of 6 months of treatment on bone mineral density and cardiovascular risk factors

Changing landscape of hematopoietic and mesenchymal cells and their interactions during aging and in age-related skeletal pathologies

Aging profoundly impacts mesenchymal and hematopoietic lineage cells, including their progenitors-the skeletal stem cells (SSCs) and hematopoietic stem cells (HSCs), respectively. SSCs are crucial for skeletal development, homeostasis, and regeneration, maintaining bone integrity by differentiating into osteoblasts, adipocytes, and other lineages that contribute to the bone marrow (BM) microenvironment. Meanwhile, HSCs sustain hematopoiesis and immune function. With aging, SSCs and HSCs undergo significant functional decline, partly driven by cellular senescence-a hallmark of aging characterized by irreversible growth arrest, secretion of pro-inflammatory factors (senescence associated secretory phenotype, SASP), and impaired regenerative potential. In SSCs, senescence skews lineage commitment toward adipogenesis at the expense of osteogenesis, contributing to increased bone marrow adiposity (BMAd), reduced bone quality, and osteoporosis. Similarly, aged HSCs exhibit diminished self-renewal, biased differentiation, and heightened inflammation, compromising hematopoietic output and immune function. In this review, we examine the age-related cellular and molecular changes in SSCs and HSCs, their lineage decisions in the aging microenvironment, and the interplay between skeletal and hematopoietic compartments. We also discuss the role of senescence-driven alterations in BM homeostasis and how targeting cellular aging mechanisms may offer therapeutic strategies for mitigating age-related skeletal and hematopoietic decline.

Effects of testosterone treatment, with and without exercise training, on ambulatory blood pressure in middle-aged and older men

CONTEXT

With age, testosterone (T) and physical activity levels often decline in parallel. The effect of combining T treatment and exercise training on ambulatory blood pressure (ABP) is unclear.

OBJECTIVE

To assess T and exercise effects, alone and in combination, on ABP in men aged 50-70 years, waist circumference ≥ 95 cm and low-normal serum T (6-14 nmol/L), without organic hypogonadism.

DESIGN

A 2 × 2 factorial randomised, placebo-controlled study.

INTERVENTION

Randomization to daily transdermal AndroForte5^® (Testosterone 5.0%w/v, 100 mg in 2 ml) cream (T), or matching placebo (P) (double-blind), and to supervised exercise (Ex) or no additional exercise (NEx), for 12 weeks.

RESULTS

Average 24-h systolic blood pressure (SBP) increased with T treatment (testosterone*time, p = .035). Average 24-h SBP increased in T+Ex (T+Ex:+3.0 vs. P+NEx: -3.0 mmHg, p = .026) driven by day-time changes (T+Ex:+3.5 vs. P+NEx: -3.0 mmHg, p = .026). There was an effect of T for 24-h average diastolic blood pressure (DBP, testosterone*time, p = .044) driven by the decrease in P+Ex (P+Ex: -3.9 vs. T+NEx: -0.5 mmHg, p = .015). Night-time DBP was lower with exercise (P+Ex: -4.0 vs. P+NEx: +0.7 mmHg, p = .032). The effect of exercise to lower night-time DBP was not apparent in the presence of T (T+Ex: -0.4 vs. P+NEx: +0.7 mmHg, p > .05). Ex increased average 24-h pulse pressure (PP, exercise*time, p = .022), largely during daytime hours (exercise*time, p = .013).

CONCLUSIONS

There was a main effect of T to increase 24-h SBP, primarily seen when T was combined with Ex. Exercise alone decreased 24-h and night-time DBP; an effect attenuated by T. BP should be carefully assessed and monitored, when prescribing T treatment to middle-aged and older men, especially when combined with exercise training.

Interaction between testosterone and obesity on hypertension: A population-based cross-sectional study

BACKGROUND AND AIMS

We aimed to evaluate the effects of serum testosterone, obesity and their interaction on blood pressure (BP) parameters and hypertension among Chinese rural adults.

METHODS

A total of 6199 adults were recruited from the Henan Rural Cohort Study. Serum testosterone was measured by liquid chromatography-tandem mass spectrometry. Logistic regression and linear regression were used to evaluate the association between testosterone, hypertension and BP parameters (including systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP), and mean arterial pressure (MAP)). A generalized linear model was performed to identify the interactive effects of testosterone and obesity on hypertension.

RESULTS

High levels of serum testosterone were associated with a lower prevalence of hypertension in males (odds ratio (OR): 0.69, 95% confidence interval (CI): 0.53, 0.89). After stratification by obesity, observed associations were only found in non-obese males. Each one-unit increase in ln-testosterone was associated with a 1.23 mmHg decrease in SBP, 0.97 mmHg decrease in DBP, and 1.05 mmHg decrease in MAP among males. Moreover, interactive effects between testosterone and obesity on hypertension and BP parameters were found, indicating that protective effects of serum testosterone on hypertension and BP parameters were counteracted and accompanied by increased values of obesity-related indicators in males, and additional testosterone increased BP parameters and prevalence of hypertension at high levels of waist-to-hip ratio and waist-to-height ratio in females.

CONCLUSIONS

Elevated levels of serum testosterone were associated with decreased BP parameters and prevalent hypertension in males, and obesity modifying effects of serum testosterone on BP parameters and hypertension.

Effects of adjunct testosterone on cardiac morphology and function in advanced cancers: an ancillary analysis of a randomized controlled trial

BACKGROUND

Adjunct testosterone therapy improves lean body mass, quality of life, and physical activity in patients with advanced cancers; however, the effects of testosterone on cardiac morphology and function are unknown. Accordingly, as an ancillary analysis of a randomized, placebo-controlled trial investigating the efficacy of testosterone supplementation on body composition in men and women with advanced cancers, we explored whether testosterone supplementation could prevent or reverse left ventricular (LV) atrophy and dysfunction.

METHODS

Men and women recently diagnosed with late stage (≥IIB) or recurrent head and neck or cervical cancer who were scheduled to receive standard of care chemotherapy or concurrent chemoradiation were administered an adjunct 7 week treatment of weekly intramuscular injections of either 100 mg testosterone (T, n = 1 M/5F) or placebo (P, n = 6 M/4F) in a double-blinded randomized fashion. LV morphology (wall thickness), systolic function (ejection fraction, EF), diastolic function (E/A; E'/E), arterial elastance (Ea), end-systolic elastance (Ees), and ventricular-arterial coupling (Ea/Ees) were assessed.

RESULTS

No significant differences were observed in LV posterior wall thickness in placebo (pre: 1.10 ± 0.1 cm; post: 1.16 ± 0.2 cm; p = 0.11) or testosterone groups (pre: 0.99 ± 0.1 cm; post: 1.14 ± 0.20 cm; p = 0.22). Compared with placebo, testosterone significantly improved LVEF (placebo: - 1.8 ± 4.3%; testosterone: + 6.2 ± 4.3%; p < 0.05), Ea (placebo: 0.0 ± 0.2 mmHg/mL; testosterone: - 0.3 ± 0.2 mmHg/mL; p < 0.05), and Ea/Ees (placebo: 0.0 ± 0.1; testosterone: - 0.2 ± 0.1; p < 0.05).

CONCLUSIONS

In patients with advanced cancers, testosterone was associated with favorable changes in left ventricular systolic function, arterial elastance, and ventricular-arterial coupling. Given the small sample size, the promising multisystem benefits of testosterone warrants further evaluation in a definitive randomized trial.

TRIAL REGISTRATION

This study was prospectively registered on ClinicalTrials.gov (NCT00878995; date of registration: April 9, 2009).

Association of total testosterone, free testosterone, bioavailable testosterone, sex hormone-binding globulin, and hypertension

Low testosterone has been inversely associated with hypertension. Our objective was to determine the associations between total testosterone (TT), free testosterone (FT), bioavailable testosterone (BioT), sex hormone-binding globulin (SHBG), and hypertension. Two hundred fifty-three men were enrolled in this study. TT and SHBG were measured by chemiluminescent immunoassay, and FT and BioT were calculated. Hypertension was defined as systolic blood pressure (SBP) ≥140 mm Hg and/or diastolic blood pressure (DBP) ≥90 mm Hg. Our results showed that hypertensive men had higher SHBG levels, and lower FT and BioT, compared to normotensive men. FT and BioT were inversely associated with SBP and DBP after adjusting for covariates (age, smoking, alcohol consumption, and physical activity). Furthermore, there was a significant decrease in the odds ratios for hypertension in the third and fourth quartiles of BioT and FT, compared to the lowest quartile before and after adjusting for covariates. In contrast, the OR for hypertension in the third quartile of SHBG was lower than the highest quartile. Our data show that FT and BioT are inversely correlated with SBP, DBP, and hypertension in men.

Evaluation of ostarine as a selective androgen receptor modulator in a rat model of postmenopausal osteoporosis

Selective androgen receptor modulators (SARMs) have shown beneficial effects on muscle wasting, general physical function and bone properties in male mammals. However, data on the effects of SARMs in postmenopausal osteoporotic bone are scarce. We evaluated the effects of the SARM drug ostarine on postmenopausal osteoporotic bone in a rat osteoporosis model. Ovariectomy was performed on 46 of 56 3-month-old female Sprague-Dawley rats. Eight weeks after ovariectomy, ostarine was orally administered daily for 5 weeks in dosages of 0.04 (low, OVX + Ost. 0.04), 0.4 (intermediate, OVX + Ost. 0.4), and 4 mg/kg (high, OVX + Ost. 4) body weight. Another ovariectomized group received no ostarine. Lumbar vertebrae and femora were removed for biomechanical, gene expression, ashing, and computer tomography analyses. Low dose showed no effects. The effects of intermediate and high doses were comparable overall. Improvements were mainly seen in structural properties such as bone mineral density and bone volume density. However, the effects in femora were superior to effects in vertebrae. Ostarine treatment for 5 weeks did not improve significantly biomechanical properties. mRNA expression of the receptor activator of NF-κB ligand decreased after treatment, and uterine weight increased. Serum levels of phosphorus increased following ostarine treatment in intermediate and high-dose groups. Short-term treatment of osteoporotic bone with ostarine leads to improvement of several microstructural bone indices. While we did not observe changes in biomechanics, it is conceivable that longer treatment may also improve biomechanical properties. Further studies are needed to characterize longer time effects and side effects of ostarine in osteoporosis.

Guidelines of the Brazilian Society of Rheumatology for the diagnosis and treatment of osteoporosis in men

Osteoporosis, a metabolic disease characterized by low bone mass, deterioration of the bone tissue microarchitecture and increased susceptibility to fractures, is commonly regarded as a women's health problem. This point of view is based on the fact that compared with men, women have lower bone mineral density and longer lifespans and lose bone mass faster, especially after menopause, due to a marked decrease in serum estrogen levels. However, in the last 20 years, osteoporosis in men has become recognized as a public health problem due to the occurrence of an increasingly higher number of fragility fractures. Approximately 30% of all hip fractures occur in men. Recent studies show that the probability of fracture due to hip, vertebral or wrist fragility in Caucasian men older than fifty years, for the rest of their lives, is approximately 13% versus a 40% probability of fragility fractures in women. Men show bone mass loss and fractures later than women. Although older men have a higher risk of fracture, approximately half of all hip fractures occur before the age of 80. Life expectancy is increasing for both sexes in Brazil and worldwide, albeit at a higher rate for men than for women. This Guideline was based on a systematic review of the literature on the prevalence, etiology, diagnosis and treatment of osteoporosis in men.

A summary of the Malaysian Clinical Guidance on the management of postmenopausal and male osteoporosis, 2015

AIM

This Clinical Guidance is aimed to help practitioners assess, diagnose and manage their patients with osteoporosis (OP), using the best available evidence.

METHODS

A literature search using PubMed (MEDLINE) and The Cochrane Library identified all relevant articles on OP and its assessment, diagnosis and treatment, from 2011, to update from the 2012 edition. The studies were assessed and the level of evidence assigned. For each statement, studies with the highest level of evidence were used to frame the recommendation.

RESULTS

This article summarizes the diagnostic and treatment pathways for postmenopausal and male OP, while addressing the risk-benefit ratio for OP treatment. Recognising the limitation of only depending on bone mineral density in assessing fracture risk, a move to assess 10 year fracture risk using tools such as FRAX, is recommended as a guide to decision-making on when to start treatment. A re-evaluation was done of the position of calcium supplementation and on the importance of vitamin D. There has been concern about the potential adverse effects of the long-term usage of bisphosphonates, which have been discussed fully. Algorithms for the management of postmenopausal and male OP have been updated.

CONCLUSIONS

Adequate intake of calcium (1000 mg from both diet and supplements) and vitamin D (800 IU) daily remain important adjuncts in the treatment of OP. However, in confirmed OP, pharmacological therapy with anti-resorptives is the mainstay of treatment in both men and postmenopausal women. Patients need to be regularly assessed while on medication and treatment adjusted as appropriate.

Androgen receptor action in osteoblasts in male mice is dependent on their stage of maturation

Androgen action via the androgen receptor (AR) is essential for normal skeletal growth and bone maintenance post-puberty in males; however, the molecular and cellular mechanisms by which androgens exert their actions in osteoblasts remains relatively unexplored in vivo. To identify autonomous AR actions in osteoblasts independent of AR signaling in other tissues, we compared the extent to which the bone phenotype of the Global-ARKO mouse was restored by replacing the AR in osteoblasts commencing at either the (1) proliferative or (2) mineralization stage of their maturation. In trabecular bone, androgens stimulated trabecular bone accrual during growth via the AR in proliferating osteoblasts and maintained trabecular bone post-puberty via the AR in mineralizing osteoblasts, with its predominant action being to inhibit bone resorption by decreasing the ratio of receptor activator of NF-κB ligand (RANKL) to osteoprotegerin (OPG) gene expression. During growth, replacement of the AR in proliferating but not mineralizing osteoblasts of Global-ARKOs was able to partially restore periosteal circumference, supporting the concept that androgen action in cortical bone to increase bone size during growth is mediated via the AR in proliferating osteoblasts. This study provides further significant insight into the mechanism of androgen action via the AR in osteoblasts, demonstrating that it is dependent on the stage of osteoblast maturation.

The effects of short-term and long-term testosterone supplementation on blood viscosity and erythrocyte deformability in healthy adult mice

Testosterone treatment induces erythrocytosis that could potentially affect blood viscosity and cardiovascular risk. We thus investigated the effects of testosterone administration on blood viscosity and erythrocyte deformability using mouse models. Blood viscosity, erythrocyte deformability, and hematocrits were measured in normal male and female mice, as well as in females and castrated males after short-term (2 wk) and long-term (5-7 mo) testosterone intervention (50 mg/kg, weekly). Castrated males for long-term intervention were studied in parallel with the normal males to assess the effect of long-term testosterone deprivation. An additional short-term intervention study was conducted in females with a lower testosterone dose (5 mg/kg). Our results indicate no rheological difference among normal males, females, and castrated males at steady-state. Short-term high-dose testosterone increased hematocrit and whole-blood viscosity in both females and castrated males. This effect diminished after long-term treatment, in association with increased erythrocyte deformability in the testosterone-treated mice, suggesting the presence of adaptive mechanism. Considering that cardiovascular events in human trials are seen early after intervention, rheological changes as potential mediator of vascular events warrant further investigation.

In vivo deletion of CAR resulted in high bone mass phenotypes in male mice

Constitutive androstane receptor (CAR) was originally identified as xenobiotic sensor that regulates the expression of cytochrome P450 genes. However, recent studies suggest that this nuclear receptor is also involved in the regulation of energy metabolism including glucose and lipid homeostasis. This study investigated the role of CAR in the regulation of bone mass in vivo using CAR(-/-) mice. Endogenous mRNA expression of CAR was observed in both primary osteoblasts and osteoclast precursors. CAR(-/-) mice have exhibited significant increase in whole body bone mineral density (BMD) by 9.5% (P < 0.01) and 5.5% (P < 0.05) at 10 and 15 weeks of age, respectively, compared with WT mice in males. Microcomputed tomography analysis of proximal tibia demonstrated a significant increase in trabecular bone volume (62.7%), trabecular number (54.1%) in male CAR(-/-) mice compared with WT mice. However, primary culture of calvarial cells exhibited no significant changes in osteogenic differentiation potential between CAR(-/-) and WT. In addition, the number of tartrate-resistant acid-phosphatase positive osteoclasts in the femur and serum level of CTx was not different between CAR(-/-) and WT mice. The higher BMD and microstructural parameters were not observed in female mice. Interestingly, serum level of testosterone in male CAR(-/-) mice was 2.5-fold higher compared with WT mice and the mRNA expressions of Cyp2b9 and 2b10 in the liver, which regulate testosterone metabolism, were significantly down-regulated in male CAR(-/-) mice. Furthermore, the difference in BMD between CAR(-/-) and WT mice disappeared at 8 weeks after performing orchiectomy. CAR(-/-) mice also exhibited significant increase in serum 1,25(OH)2 D3 levels but Cyp 27B1 which converts 25(OH)D3 to 1,25(OH)2 D3 was significantly down-regulated compared to WT mice. These results suggest that in vivo deletion of CAR resulted in higher bone mass, which appears to be a result from reduced metabolism of testosterone due to down-regulation of Cyp2b.

Effects of three different medications on metabolic parameters and testicular volume in patients with hypogonadotropic hypogonadism: 3-year experience

INTRODUCTION

The aim of this study was to demonstrate the influences of three different treatment strategies on biochemical parameters and testicular volume (TV) in patients with idiopathic hypogonadotropic hypogonadism (IHH).

SUBJECTS DESIGN AND METHODS

Seventy-seven never-treated patients with IHH and age and body mass index (BMI)-matched 42 healthy controls were analysed in a retrospective design. Twenty-eight patients were treated with testosterone esters (TE), 25 patients were treated with human chorionic gonadotropin (hCG) and 24 patients were treated with testosterone gel (TG). Biochemical parameters, tanner stages (TS) and TV were evaluated before and after 6 months of treatment.

RESULTS

Pretreatment TV, TS and biochemical test results were similar among the three treatment subgroup. In the TE-treated group, BMI, haemoglobin, haematocrit, creatinine, triglyceride, total testosterone (TT), TS and TV increased, but HDL-cholesterol (C) and urea level decreased significantly. In the hCG-treated group, triglyceride level decreased, and luteinizing hormone level, TS and TV increased significantly. BMI, TT, TS and TV increased, and leucocyte count, total-C, HDL-C levels decreased significantly in the TG-treated patients. No treatment type resulted in any changes in insulin resistance markers.

CONCLUSION

hCG treatment resulted in favourable effects particularly on TV and lipid parameters. When TV improvement is considered less important, TG treatment may be a better option for older patients with IHH because of its easy use, neutral effects on triglyceride, haemoglobin and haematocrit, and its beneficial effects on total cholesterol level.

Bone health and associated metabolic complications in neuromuscular diseases

This article reviews the recent literature regarding bone health as it relates to the patient living with neuromuscular disease (NMD). Studies defining the scope of bone-related disease in NMD are scant. The available evidence is discussed, focusing on abnormal calcium metabolism, increased fracture risk, and the prevalence of both scoliosis and hypovitaminosis D in Duchenne muscular dystrophy, amyotrophic lateral sclerosis, and spinal muscular atrophy. Future directions are discussed, including the urgent need for studies both to determine the nature and extent of poor bone health, and to evaluate the therapeutic effect of available osteoporosis treatments in patients with NMD.

Testosterone and cardiovascular disease in men

Despite regional variations in the prevalence of coronary artery disease (CAD), men are consistently more at risk of developing and dying from CAD than women, and the gender-specific effects of sex hormones are implicated in this inequality. This 'Perspectives' article reviews the current evidence regarding the cardiovascular effects of testosterone in men including an examination of the age-related decline in testosterone, the relationship between testosterone levels and coronary disease, coronary risk factors and mortality. We also review the vaso-active effects of testosterone, and discuss how these have been used in men with heart failure and angina. We discuss the 'cause' versus 'effect' controversy, regarding low testosterone levels in men with coronary heart disease, as well as concerns over the use of testosterone replacement therapy in middle aged and elderly men. The article concludes with a discussion regarding the future direction for work in this interesting area, including the relative merits of screening for, and treating hypogonadism with testosterone replacement therapy in men with heart disease.

Testosterone and metabolic syndrome: The link

Metabolic syndrome (MetS) or "Syndrome X" which is a constellation of insulin resistance, hyperglycemia, hypertension, low high-density lipoprotein cholesterol (HDL-C), and increased very-low-density lipoprotein (VLDL) and triglyceride (TG) levels. It is one of the main threats for public health in the 21st century with its associated risk of cardiovascular disease. This condition affects a major chunk of mankind. International Diabetes Federation (IDF) estimated that around 20-25% of the adult population of the world has MetS. Several definitions have been put forward by different expert bodies leading to confusion. To overcome this, joint new statement of many expert group have been issued. Serum testosterone (T) has been shown to be associated with MetS. Several studies have shown a higher prevalence of MetS in subjects with low testosterone. There are also several studies showing a significant difference in serum T between those with MetS and those without. Serum T has also been shown to be associated with components of MetS and testosterone replacement therapy (TRT) improves various metabolic and anthropometric parameters in MetS. Patients with androgen deprivation for treatment of various cancers have also been reported to have higher prevalence of MetS. But the evidence of association is not sufficient evidence for the causation of MetS by low testosterone and long-term studies are needed to confirm whether T deficiency is the cause or is a feature of MetS.

Onset of effects of testosterone treatment and time span until maximum effects are achieved

OBJECTIVE

Testosterone has a spectrum of effects on the male organism. This review attempts to determine, from published studies, the time-course of the effects induced by testosterone replacement therapy from their first manifestation until maximum effects are attained.

DESIGN

Literature data on testosterone replacement.

RESULTS

Effects on sexual interest appear after 3 weeks plateauing at 6 weeks, with no further increments expected beyond. Changes in erections/ejaculations may require up to 6 months. Effects on quality of life manifest within 3-4 weeks, but maximum benefits take longer. Effects on depressive mood become detectable after 3-6 weeks with a maximum after 18-30 weeks. Effects on erythropoiesis are evident at 3 months, peaking at 9-12 months. Prostate-specific antigen and volume rise, marginally, plateauing at 12 months; further increase should be related to aging rather than therapy. Effects on lipids appear after 4 weeks, maximal after 6-12 months. Insulin sensitivity may improve within few days, but effects on glycemic control become evident only after 3-12 months. Changes in fat mass, lean body mass, and muscle strength occur within 12-16 weeks, stabilize at 6-12 months, but can marginally continue over years. Effects on inflammation occur within 3-12 weeks. Effects on bone are detectable already after 6 months while continuing at least for 3 years.

CONCLUSION

The time-course of the spectrum of effects of testosterone shows considerable variation, probably related to pharmacodynamics of the testosterone preparation. Genomic and non-genomic effects, androgen receptor polymorphism and intracellular steroid metabolism further contribute to such diversity.

Inverse association between total testosterone concentrations, incident hypertension and blood pressure

BACKGROUND

Studies on the relationship between testosterone concentrations and blood pressure have yielded inconsistent results. Therefore, this study investigated the prospective association of total testosterone (TT) concentrations with risk of incident hypertension and blood pressure change in 1,484 men aged 20-79 years.

METHODS

Data from the population-based Study of Health in Pomerania, Germany, were used. Serum TT concentrations, measured by chemiluminescent enzyme immunoassays, were categorised into age-specific quartiles. Generalised Estimating Equation (GEE) models, adjusted for age, waist circumference, physical activity, smoking and alcohol consumption were specified.

RESULTS

During a median follow-up time of 5.0 years, the prevalence of hypertension increased from 50.6% to 57.1%. TT concentrations were significantly lower in men with baseline and incident hypertension. Analyses revealed that men with baseline TT concentrations in the lowest quartile had an increased risk of incident hypertension (odds ratio (OR), 1.19 (95% CI, 1.10-1.28)) compared to men with higher TT concentrations. Furthermore, we found a significant inverse association of TT concentrations and blood pressure, showing that men with baseline TT concentrations in the lowest quartile showed the slightest change in systolic blood pressure (-6.01 mmHg), diastolic blood pressure (-2.11 mmHg) and pulse pressure (-3.98 mmHg). Sensitivity analyses in a subpopulation of men without antihypertensive medication confirmed these findings.

CONCLUSION

These results show that low male TT concentrations are predictive of hypertension, suggesting TT as a potential biomarker of increased cardiovascular risk.

Association between generic and disease-specific quality of life questionnaires and mobility and balance among women with osteoporosis and vertebral fractures

BACKGROUND AND AIMS

The aims of this study were to assess correlations between two health-related quality of life (HRQOL) measurements, the Quality of Life Questionnaire issued by the European Foundation for Osteoporosis (QUALEFFO- 41) and the total score of The General Health Questionnaire (GHQ-20) in a population of women living at home with well-established osteoporosis and at least one vertebral fracture, as well as the internal consistency and floor and ceiling effects of these measurements. Also examined were the mean values of these measurements, to ascertain whether they were significantly different for the group consisting of 75% of the women with the best performance on mobility and balance, compared with the other participants.

METHODS

Across-sectional study of 89 women aged 60 years or more, evaluated by QUALEFFO-41 (consisting of one total score and five section scores), GHQ-20 (one total score), maximum speed and Functional Reach (FR).

RESULTS

Cronbach's alpha coefficient for measurements of HRQOL ranged from 0.61 to 0.92. Significant correlations between 'QUALEFFO- 41: total score' and 'GHQ-20: total score' were 0.49, and between 'GHQ-20: total score' and section scores of 'QUALEFFO-41' 0.28-0.63. Those in the 75% group with the highest maximum walking speed or longest distance on FR reported significantly better disease-specific HRQOL than the others, with poorer results on these tests.

CONCLUSIONS

Disease-specific and generic HRQOL instruments are not redundant when applied together, and the disease-specific 'QUALEFFO-41' and generic GHQ-20 measure different aspects of HRQOL.

Long-term Safety of Testosterone and Growth Hormone Supplementation: A Retrospective Study of Metabolic, Cardiovascular, and Oncologic Outcomes

Background

Clinical research into the effects of hormonal supplementation has tended to focus on beneficial changes in anthropometric measures. There are fewer data on long-term safety with extended hormonal supplementation.

Methods

As part of a retrospective database survey, clinical outcomes were tabulated among patients who received at least 1 year of testosterone and/or growth hormone (GH) supplementation. In patients who were treated for at least 2 years, changes in markers of glucose and lipid metabolism were analyzed with and without concomitant use of oral hypoglycemics and statins.

Results

In 263 patients (mean age 56) treated for at least 2 years, the only statistically significant effect on markers of glucose metabolism was an increase in glycated hemoglobin (still within normal limits) in patients receiving GH alone or in combination with testosterone but without oral hypoglycemics; with or without hypoglycemics, insulin levels showed no significant change. The only significant effects on markers of lipid metabolism were decreases in total cholesterol and low-density lipoprotein (LDL) in patients receiving combined testosterone and GH without statins. Decreases in LDL were significant in both the statin and non-statin groups; decreases in triglycerides were significant only in the statin group. In 531 patients treated for at least 1 year (mean age 54), the overall incidence of adverse clinical outcomes (prostate disease, diabetes, cardiovascular disease, cancer) was 1.3%.

Conclusions

In this retrospective survey, extended testosterone and/or GH supplementation did not adversely affect metabolic markers or clinical outcomes.

Keywords

Safety; Testosterone; Growth hormone; Supplementation

Osteoporosis in Men

The prevalence of osteoporosis is estimated to be 18% in men, but 30% of all fractures occur in men. With age, men experience a gradual decline in testosterone production and bone density. The rate of trabecular bone loss in the lumbar spine in men over age 50 can be double the rate of loss in men under age 50. Endogenous testosterone, estradiol, and their metabolites play a role in maintaining bone health, but their specific effects on bone turnover have been difficult to elucidate. Recently, large cohort studies have provided more detailed information confirming estrogen’s associations and further characterizing the effect of endogenous testosterone and its metabolites on bone mineral density and fractures. Very few clinical trials have assessed the impact of testosterone replacement therapy (TRT) on bone density and fractures in men. The few studies that have been conducted are generally small and not robust enough to show the true treatment effect of TRT and adequately determine its safety. In the absence of data on patient outcomes, it is important for pharmacists to understand the impact of drug therapy on biomarkers and surrogate markers of disease for optimal pharmacotherapy selection and monitoring.

Testosterone and the metabolic syndrome

Metabolic syndrome and testosterone deficiency in men are closely Linked. Epidemiological studies have shown that Low testosterone Levels are associated with obesity, insulin resistance and an adverse Lipid profile in men. Conversely in men with metabolic syndrome and type 2 diabetes have a high prevalence of hypogonadism. Metabolic syndrome and Low testosterone status are both independently associated with increased all-cause and cardiovascular mortality. Observational and experimental data suggest that physiological replacement of testosterone produces improvement in insulin resistance, obesity, dyslipidae-mia and sexual dysfunction along with improved quality of Life. However, there are no Long-term interventional studies to assess the effect of testosterone replacement on mortality in men with Low testosterone Levels. This article reviews the observational and interventional clinical data in relation to testosterone and metabolic syndrome.

Effects of testosterone on Type 2 diabetes and components of the metabolic syndrome

Observations from clinical studies suggest that low serum levels of testosterone in men are often associated with obesity, insulin resistance, and metabolic compromise. Indeed, the clinical symptoms of late-onset hypogonadism are markedly similar to those of Type 2 diabetes mellitus (T2DM) and metabolic syndrome, and may share a similar pathophysiology. Observational and experimental data suggest that testosterone treatment improves a number of hallmark features of T2DM and metabolic syndrome, namely insulin resistance, obesity, dyslipidemia, and sexual dysfunction. Consequently, clinical studies have been undertaken to assess the impact of testosterone-replacement therapy in this patient group. The present article reviews the observational clinical data suggesting an association between low serum testosterone and metabolic impairment, the clinical data relating to the effects of testosterone treatment on components of the metabolic syndrome, and the randomized clinical trails that have formally investigated whether testosterone-replacement therapy provides clinical benefit to hypogonadal men with T2DM and/or metabolic syndrome.

Late-life onset hypogonadism: a review

Increased longevity and population aging will increase the number of men with late-onset hypogonadism, a common condition that is often under diagnosed and under treated. The indication of testosterone replacement therapy (TRT) treatment requires the presence of low testosterone level and symptoms and signs of hypogonadism. Although there is a lack of large-scale, long-term studies assessing the benefits and risks of TRT in men with hypogonadism, reports indicate that TRT may produce a wide range of benefits that include improvement in libido and sexual function, bone density, muscle mass, body composition, mood, erythropoiesis, cognition, quality of life, and cardiovascular disease. Perhaps the most controversial area is the issue of risk, especially the possible stimulation of prostate cancer by testosterone, even though there is no evidence to support this risk. Other possible risks include worsening symptoms of benign prostatic hypertrophy, liver toxicity, hyperviscosity, erythrocytosis, worsening untreated sleep apnea, or severe heart failure. Despite this controversy, testosterone supplementation in the United States has increased substantially in the past several years. The physician should discuss with the patient the potential benefits and risks of TRT. This review discusses the benefits and risks of TRT.

Androgens and osteoporosis

PURPOSE OF REVIEW

The review is timely given recent advances regarding mechanisms of androgen action on bone cells and in humans. Osteoporosis in men is an important public health problem. An improved understanding of the role of androgens in the pathophysiology of bone loss will lead to new treatments.

RECENT FINDINGS

Androgen receptors are present in most bone cells. Testosterone acts on bone both directly via the androgen receptor and indirectly, following aromatization, via the oestrogen receptor. During skeletal modelling, ERalpha is critical for longitudinal bone growth. For periosteal growth and bone expansion, androgen receptor activation has a positive effect, whereas ERalpha activation is inhibitory. During skeletal remodelling, both receptor pathways generate similar and additive effects on bone.Androgen deficiency is a common secondary cause of osteoporosis in men and should be treated with testosterone, particularly in symptomatic men. However, lack of efficacy data for testosterone in osteoporosis means it is less useful as a first-line treatment in men with age-related declines in testosterone and osteoporosis, when other agents such as bisphosphonates and parathyroid hormone are effective.

SUMMARY

Randomized, placebo-controlled trials of testosterone therapy in men with age-related declines in testosterone and osteoporosis are needed, and should carefully evaluate potential risks, as well as its efficacy in reducing fractures and other health benefits.

The benefits and risks of testosterone replacement therapy: a review

Increased longevity and population aging will increase the number of men with late onset hypogonadism. It is a common condition, but often underdiagnosed and undertreated. The indication of testosterone-replacement therapy (TRT) treatment requires the presence of low testosterone level, and symptoms and signs of hypogonadism. Although controversy remains regarding indications for testosterone supplementation in aging men due to lack of large-scale, long-term studies assessing the benefits and risks of testosterone-replacement therapy in men, reports indicate that TRT may produce a wide range of benefits for men with hypogonadism that include improvement in libido and sexual function, bone density, muscle mass, body composition, mood, erythropoiesis, cognition, quality of life and cardiovascular disease. Perhaps the most controversial area is the issue of risk, especially possible stimulation of prostate cancer by testosterone, even though no evidence to support this risk exists. Other possible risks include worsening symptoms of benign prostatic hypertrophy, liver toxicity, hyperviscosity, erythrocytosis, worsening untreated sleep apnea or severe heart failure. Despite this controversy, testosterone supplementation in the United States has increased substantially over the past several years. The physician should discuss with the patient the potential benefits and risks of TRT. The purpose of this review is to discuss what is known and not known regarding the benefits and risks of TRT.

Testosterone, but not IGF-1, LH, prolactin or cortisol, may serve as antler-stimulating hormone in red deer stags (Cervus elaphus)

The role of androgens and insulin-like growth factor 1 (IGF-1) in antler growth has been disputed. We predicted that the secretory of IGF-1 may be associated with an acceleration of body growth rather than with antler growth. Furthermore we anticipated a relationship between the increase of testosterone and the progress of antler growth. If IGF-1 is involved in the stimulation of antler growth, this should be more obvious in young than in mature stags. Eight two-year-old red deer stags (Cervus elaphus), and twelve adult red deer stags were blood sampled and the length of their velvet antlers was measured in one-week intervals during the period of antler growth. Concentrations of testosterone, cortisol, IGF-1, luteinizing hormone (LH), and prolactin were determined in plasma by enzyme immunoassay or radioimmunoassay. Antler growth per day was primarily dependent on changes in testosterone concentration per day in both groups of stags. As expected, only in two-year-old stags we detected a possible role of IGF-1 in the antler growth regulation, but that was not in agreement with previously published studies. Nevertheless, this effect was still utilized in interaction with testosterone. In addition to total antler length, only concentrations of testosterone and LH were significantly higher in adult males in comparison to two-year-old males. Our present results lead us to conclude that it is not IGF-1 but testosterone which is responsible for the intensity of antler growth in subadult and adult red deer stags.

Androgens and bone

Testosterone is the major gonadal sex steroid produced by the testes in men. Testosterone is also produced in smaller amounts by the ovaries in women. The adrenal glands produce the weaker androgens dehydroepiandrosterone, dehydroepiandrosterone sulfate, and androstenedione. These androgens collectively affect skeletal homeostasis throughout life in both men and women, particularly at puberty and during adult life. Because testosterone can be metabolized to estradiol by the aromatase enzyme, there has been controversy as to which gonadal sex steroid has the greater skeletal effect. The current evidence suggests that estradiol plays a greater role in maintenance of skeletal health than testosterone, but that androgens also have direct beneficial effects on bone. Supraphysiological levels of testosterone likely have similar effects on bone as lower levels via direct interaction with androgen receptors, as well as effects mediated by estrogen receptors after aromatization to estradiol. Whether high doses of synthetic, non-aromatizable androgens may, in fact, be detrimental to bone due to suppression of endogenous testosterone (and estrogen) levels is a potential concern that warrants further study.

The role of testosterone in the metabolic syndrome: a review

Over the last three decades it has become apparent that testosterone plays a significant role in the maintenance of bone and muscle mass, in erythropoiesis, and in mental functions. But testosterone is also a key player in glucose homeostasis and lipid metabolism. The metabolic syndrome is a clustering of risk factors predisposing to late onset diabetes mellitus, atherosclerosis and cardiovascular morbidity and mortality. The main components of the syndrome are visceral obesity, glucose intolerance, raised blood pressure and dyslipidaemia (elevated triglycerides, low levels of high-density lipoprotein cholesterol),and a pro-inflammatory and thrombogenic state. Cross-sectional epidemiological studies have reported a direct correlation between plasma testosterone and insulin sensitivity, and low testosterone levels are associated with an increased risk of type 2 diabetes mellitus, dramatically illustrated by androgen deprivation in men with prostate carcinoma. Lower total testosterone and sex hormone-binding globulin(SHBG) predict a higher incidence of the metabolic syndrome. There is now evidence to argue that hypotestosteronaemia should be an element in the definition of the metabolic syndrome. Administration of testosterone to hypogonadal men reverses the unfavorable risk profile for the development of diabetes and atherosclerosis. Testosterone should be regarded as a pivotal hormone for men's health.

The impact of sex hormone changes on bone mineral deficit in chronic renal failure

In chronic renal failure several factors affect bone homeostasis leading to the development of renal osteodystrophy. Common calcitropic hormone derangements in renal failure play a central role in bone structure and mineral defects, which in turn accompany osteodystrophy frequently resulting in low bone mineral density (BMD) values. However, patients with end-stage renal disease (ESRD) suffer from several comorbidities, which may partly account for renal bone disease lesions. Hypogonadism in particular accompanies chronic renal failure frequently and exerts an additive effect on bone loss potential. Sex hormones contribute to the equilibrium of osteotropic hormones and cytokines, exerting a protective action on bone tissue. Estrogens have a regulatory effect on bone metabolism in women with renal failure as well. Hypogonadal ESRD women experience a higher bone turnover and more significant bone mass decrements than ESRD women with relatively normal hormone profile and menstrual habits. Female hemodialysis patients have lower BMD values than male patients on average, probably because of menstrual cycle irregularities. However, hypogonadal ESRD men may also experience bone mineral deficits and the severity of hypogonadism may correlate to their bone mineral status. Hormone replacement therapy (HRT) appears to reverse bone mineral loss to some extent in both sexes. In conclusion hypogonadism in renal failure contributes to the bone structure and mineral defects as well as the low-energy fracture risk, reflected in BMD measurements. HRT in ESRD patients should therefore not be overlooked in these patients in the face of their significant comorbidities.

Prevalence of hypogonadism in male patients with renal failure

BACKGROUND

Hypogonadism in men may be secondary to renal failure and is well recognised in patients with end-stage renal disease. It is thought to contribute to the sexual dysfunction and osteoporosis experienced by these patients. However, the association between hypogonadism and lesser degrees of renal dysfunction is not well characterised.

METHODS

The gonadal status of 214 male patients (mean age 56 (SD 18) years) attending a renal centre was studied; 62 of them were receiving haemodialysis and 22 continuous ambulatory peritoneal dialysis for end-stage renal disease, whereas 34 patients had functioning renal transplants and 96 patients were in the low-clearance phase. Non-fasting plasma was analysed for testosterone, follicle-stimulating hormone, luteinising hormone, sex hormone-binding globulin, parathyroid hormone and haemoglobin. Creatinine clearance was estimated in patients not on dialysis, and Kt/V and urea reduction ratio were assessed in patients on dialysis. Testosterone concentrations were classified as normal (>14 nmol/l), low-normal (10-14 nmol/l) or low (<10 nmol/l).

RESULTS

56 (26.2%) patients had significantly low testosterone levels and another 65 (30.3%) had low-normal levels. No significant changes were seen in sex hormone-binding globulin or gonadotrophin levels. Gonadal status was not correlated with haemoglobin level, parathyroid hormone level, creatinine clearance, or dialysis duration or adequacy.

CONCLUSION

Over half of patients with renal failure, even in the pre-dialysis phase, have low or low-normal levels of testosterone, which may be a potentially reversible risk factor for osteoporosis and sexual dysfunction. These patients may be candidates for testosterone-replacement therapy, which has been shown to improve bone mineral-density and libido in men with low and low-normal testosterone levels.

Selective Androgen Receptor Modulator (SARM) treatment prevents bone loss and reduces body fat in ovariectomized rats

PURPOSE

This study was conducted to examine the bone and body composition effects of S-4, an aryl-propionamide derived Selective Androgen Receptor Modulator (SARM) in an ovariectomy induced model of accelerated bone loss.

METHODS

One hundred twenty female Sprague-Dawley rats aged to twenty-three weeks were randomly assigned to twelve treatment groups. Drug treatment was initiated immediately following ovariectomy and continued for one hundred twenty days. Whole body bone mineral density (BMD), body composition, and lumbar vertebrae BMD were measured by dual energy x-ray absorptiometry. More stringent regional pQCT and biomechanical strength testing was performed on excised femurs.

RESULTS

We found that S-4 treatment maintained whole body and trabecular BMD, cortical content, and increased bone strength while decreasing body fat in these animals.

CONCLUSIONS

The data presented herein show the protective skeletal effects of S-4. Our previous reports have shown the tissue selectivity and muscle anabolic activity of S-4. Together these data suggest that S-4 could reduce the incidence of fracture via two different mechanisms (i.e., via direct effects in bone and reducing the incidence of falls through increased muscle strength). This approach to fracture reduction would be advantageous over current therapies in these patients which are primarily antiresorptive in nature.

Pharmacotherapy of osteoporosis in men

Osteofragility fractures occur in men due to a compromise in bone strength, coupled with either trauma or a fall. In men >or= 65years of age, osteoporosis can be defined as bone mineral density (at the proximal femur, spine or distal forearm) of 2.5 standard deviations or less below the mean for a normal young adult man, using a male reference database (i.e., T-score value of <or=-2.5) [1,2]. In men 50 - 65 years of age, a similar definition is used if other risk factors for a fracture are present. Osteoporosis is increasingly recognised in men [3-11]. One in three men aged > 60 years will suffer an osteoporotic fracture [3]. Spinal fractures occur in 5% of men (compared with 16% of women) and hip fractures in 6% of men (compared with 18% of women) > 50 years of age [8]. The risk of hip fracture increases by approximately 2.6-fold for each standard deviation decrease in bone density measured at the hip [12,13]. At present, the life expectancy for men has increased to a mean age of 76.8 years. With men now living longer, they can be expected to develop multiple coexisting illnesses contributing to bone loss and an increased likelihood of falling and fragility fractures [5,14,15]. It is estimated that 30 - 60% of men presenting with spinal fractures have another illness contributing to their bone disease [4,6-10,16-20]. The ideal therapy for men with osteoporosis should include an intervention which significantly increases bone strength and reduces fracture rates, is safe, easy to administer and economical. This review outlines the current treatment strategies available for men with osteoporosis.

Testosterone therapy in men with moderate severity heart failure: a double-blind randomized placebo controlled trial

AIMS

Chronic heart failure is associated with maladaptive and prolonged neurohormonal and pro-inflammatory cytokine activation causing a metabolic shift favouring catabolism, vasodilator incapacity, and loss of skeletal muscle bulk and function. In men, androgens are important determinants of anabolic function and physical strength and also possess anti-inflammatory and vasodilatory properties.

METHODS AND RESULTS

We conducted a randomized, double-blind, placebo-controlled parallel trial of testosterone replacement therapy (5 mg Androderm) at physiological doses in 76 men (mean+/-SD, age 64+/-9.9) with heart failure (ejection fraction 32.5+/-11%) over a maximum follow-up period of 12 months. The primary endpoint was functional capacity as assessed by the incremental shuttle walk test (ISWT). At baseline, 18 (24%) had serum testosterone below the normal range and bioavailable testosterone correlated with distance walked on the initial ISWT (r=0.3, P=0.01). Exercise capacity significantly improved with testosterone therapy compared with placebo over the full study period (mean change +25+/-15 m) corresponding to a 15+/-11% improvement from baseline (P=0.006 ANOVA). Symptoms improved by at least one functional class on testosterone in 13 (35%) vs. 3 (8%) on placebo (P=0.01). No significant changes were found in handgrip strength, skeletal muscle bulk by cross-sectional computed tomography, or in tumour necrosis factor levels. Testosterone therapy was safe with no excess of adverse events although the patch preparation was not well tolerated by the study patients.

CONCLUSION

Testosterone replacement therapy improves functional capacity and symptoms in men with moderately severe heart failure.

Decreased bone mineral density at the distal radius, but not at the lumbar spine or the femoral neck, in Japanese type 2 diabetic patients

The purpose of this study is to assess the association between type 2 diabetes and bone mineral density. This study included 145 Japanese patients (64 men and 81 women) with type 2 diabetes and 95 non-diabetic control subjects (41 men and 54 women) of similar age. We measured bone mineral density (BMD) at the sites with different cortical/cancellous bone ratio (lumbar spine, femoral neck, and distal radius) using dual-energy X-ray absorptiometry. BMD and Z score at the distal radius were significantly lower in type 2 diabetic patients than those in control subjects, and in type 2 diabetic patients, the Z score at the distal radius was lower than that at their own lumbar spine and femoral neck. In type 2 diabetic patients, negative correlation between BMD and the mean HbA1c during the previous 2 years was found significantly at the distal radius in both genders and at the femoral neck in women. These results indicate the selective cortical bone loss in type 2 diabetes and suggest the importance of also determining BMD at the radius and keeping good metabolic control to prevent bone loss in type 2 diabetic patients.

Androgens and the ageing male

Serum testosterone levels peak in early adulthood in men and fall progressively with age. Since sex hormone binding globulin increases with age, the unbound forms of testosterone (free and bioavailable testosterone) fall more steeply than total testosterone levels. Serum testosterone levels below the normal range for young healthy adult males provide chemical evidence of androgen deficiency independent of the age of the patient. When accompanied by signs or symptoms that are compatible with androgen deficiency, treatment with testosterone should be considered in older men without evidence of prostate or breast cancer. While such therapy for younger hypogonadal men has shown benefit on libido, mood, muscle mass, muscle strength, bone mineral density and haematocrit, similar benefits in older men have not been as adequately assessed. While there is no convincing evidence that testosterone treatment in older men will increase the risk of cardiovascular or prostate cancer, long-term, well-controlled studies are lacking and needed. Treatment options for older men include injectable, transdermal and transbuccal testosterone preparations.

Effects of Nandrolone Decanoate on &OV0312;O2max, Running Economy, and Endurance in Rats

PURPOSE

The aim of the present study was to determine the effects of treatment with an anabolic androgenic steroid (AAS), nandrolone decanoate, on the submaximal running endurance (SRE), maximum oxygen consumption (VO2max), running economy (VO2submax), and blood oxygen carrying capacity of endurance trained rats.

METHODS

Forty male Wistar rats were randomly allocated into two groups: a sedentary group and an exercising group training on treadmill for 8 wk. Half of the trained and half of the sedentary rats received weekly either nandrolone decanoate (10 mg x kg(-1)) or placebo (Pl) for the last 6 wk of experiment. SRE and VO2max tests were performed several times for all four groups (N = 10 each).Red blood cells parameters were measured at the end of the experiment.

RESULTS

The trained rats had increased their SRE compared with sedentary rats throughout the experiment. At the end of the trial, the trained rats receiving nandrolone decanoate ran 46% longer than trained rats receiving Pl during the SRE test (P < 0.05). At the end of the experiment, trained rats had greater maximal time to exhaustion and higher VO2max than those of the sedentary rats but there were no differences in VO2max, VO2submax, and red blood cells parameters between the trained rats receiving nandrolone decanoate and those receiving Pl.

CONCLUSIONS

Nandrolone decanoate has no effect on the SRE, VO2max and VO2submax of untrained rats. AAS treatment combined with submaximal training enhances SRE more than training alone but exerts no additive effects on VO2max, running economy, and oxygen carrying capacity of blood. The results suggest that this improvement in SRE of trained rats is due to the impact of AAS on other factors involved in exercise adaptation.

Androgens and bone

Loss of estrogens or androgens increases the rate of bone remodeling by removing restraining effects on osteoblastogenesis and osteoclastogenesis, and also causes a focal imbalance between resorption and formation by prolonging the lifespan of osteoclasts and shortening the lifespan of osteoblasts. Conversely, androgens, as well as estrogens, maintain cancellous bone mass and integrity, regardless of age or sex. Although androgens, via the androgen receptor (AR), and estrogens, via the estrogen receptors (ERs), can exert these effects, their relative contribution remains uncertain. Recent studies suggest that androgen action on cancellous bone depends on (local) aromatization of androgens into estrogens. However, at least in rodents, androgen action on cancellous bone can be directly mediated via AR activation, even in the absence of ERs. Androgens also increase cortical bone size via stimulation of both longitudinal and radial growth. First, androgens, like estrogens, have a biphasic effect on endochondral bone formation: at the start of puberty, sex steroids stimulate endochondral bone formation, whereas they induce epiphyseal closure at the end of puberty. Androgen action on the growth plate is, however, clearly mediated via aromatization in estrogens and interaction with ERalpha. Androgens increase radial growth, whereas estrogens decrease periosteal bone formation. This effect of androgens may be important because bone strength in males seems to be determined by relatively higher periosteal bone formation and, therefore, greater bone dimensions, relative to muscle mass at older age. Experiments in mice again suggest that both the AR and ERalpha pathways are involved in androgen action on radial bone growth. ERbeta may mediate growth-limiting effects of estrogens in the female but does not seem to be involved in the regulation of bone size in males. In conclusion, androgens may protect men against osteoporosis via maintenance of cancellous bone mass and expansion of cortical bone. Such androgen action on bone is mediated by the AR and ERalpha.

Idiopathic or Hypogonadal Osteoporosis in Men

Osteoporosis is being recognized increasingly in men, and represents a substantial public health problem. As the male population ages and lives longer, the incidence of osteoporotic fractures is expected to increase. The current lifetime risk for a fragility fracture is approximately 27% in men aged 50 years or more, and will increase further over the next 20 years. A major problem with osteoporosis in men is that it continues to be unrecognized, and the majority of men with fragility fractures due to osteoporosis are not being treated. A higher level of awareness is required amongst both general practitioners and the general public that osteoporosis is a treatable condition that can affect men. Secondary causes for osteoporosis are more common in men than in women, and require rigorous exclusion and treatment. Undiagnosed clinical hypogonadism is a common cause of osteoporosis in men, and is readily treatable. The cause of primary osteoporosis in men is unknown, but it results in an osteoblast defect. Genetic factors are likely to be important. In some but not all men, relative estrogen deficiency contributes to rapid rates of age-related bone loss and fractures. An adequate calcium intake, regular weight-bearing exercise, and normal vitamin D status are all very important, particularly with increasing age. The role of testosterone in treating eugonadal men with osteoporosis is currently unclear, and larger prospective studies will be required to carefully evaluate the benefits and risks of therapy. First-line treatment of osteoporosis in hypogonadal or eugonadal men is with bisphosphonates. Alendronate increases bone density and reduces vertebral fractures measured using a semiquantitative method in eugonadal or hypogonadal men with osteoporosis. In the near future, it is likely that subcutaneous human parathyroid hormone (1-34) or teriparatide will also be available as an important new anabolic treatment for men with osteoporosis. Teriparatide treatment also increases bone density in men. Selective estrogen receptor modulating drugs require further evaluation in men, but would appear to theoretically benefit men, especially those with low estradiol levels. In the future, selective androgen receptor modulating drugs may be useful in the prevention and treatment of osteoporosis, and in increasing lean body mass in men, without having adverse effects on prostate and breast tissue.

Andropause:

There is increasing evidence that the common condition of hypogonadism in older men when associated with symptoms responds well to testosterone replacement. Over the last few years there has been a marked increase in the awareness and treatment of the andropause [137]. Long-term side effects of testosterone are uncertain with only eight people over 50 years having been studied for 10 years [138]. Testosterone needs to be considered a quality-of-life drug, similar to sildenafil, and at present it should be used only if it produces symptomatic improvement. There is a need for a men's health study to determine the long-term efficacy and safety of testosterone replacement in older persons.