Increase in the prevalence of metabolic syndrome among workers according to age

Androgen levels decline over a man's lifetime. In a proportion of men (increasing with age), levels fall below values that have been established by conventional laboratory criteria as indicative of hypogonadism. Testosterone has a wide range of non-reproductive actions: it preserves bone and muscle mass, it acts on non-sexual mental functioning and it stimulates red blood cell formation. Long-term androgen deficiency has a great impact on quality of life. The first intervention studies provide indications that androgen treatment of men with true androgen deficiency is helpful. Obviously, only men who are testosterone-deficient will benefit from androgen supplementation. The diag nosis of testosterone deficiency in old age is not unambiguous. Signs and symptoms of aging sometimes clinically overlap with those of testosterone deficiency. The groups that are at higher risk of testosterone deficiency are those men with disease (pulmonary disease, gastrointestinal disease, rheumatoid disease, etc.). Usually, sex hormone binding globulin levels increase with aging, leading to lower levels of free, biologically available testosterone. For the time being, arbitrary criteria for testosterone deficiency in aging men have to be adopted. The best practical approach is to calculate the free testosterone level. The calculation can be found at www.issam.ch under 'Tools'.     

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.     

Testosterone and erectile physiology

The role of testosterone deficiency in sexual dysfunction is an important aspect of aging, because it affects such a large proportion of men over 50 years old. A number of age-related factors can cause sexual dysfunction (in particular erectile dysfunction) and testosterone deficiency, such as chronic illness and multiple medications, and the causative link between hypogonadism and erectile dysfunction is still debated. However, studies in castrated animals have proven that addition of testosterone, and its conversion to dihydrotestosterone, can restore erectile function. It appears that testosterone achieves this by peripheral mechanisms (endothelial dependent and independent) and central mechanisms. Testosterone replacement therapy is therefore effective for erectile dysfunction in men with hypogonadism, with success rates of 35–40%. Testosterone supplementation is also important in men who fail on phosphodiesterase type-5 inhibitors, because a minimum plasma concentration of testosterone is required for the successful restoration of erectile function with these agents. Testosterone gels are now the preferred formulation for testosterone supplementation and they can be highly beneficial in a proportion of men with erectile dysfunction.     

Testosterone and the brain

Gender differences in spatial recognition, and age-related declines in cognition and mood, point towards testosterone as an important modulator of cerebral functions. Testosterone appears to activate a distributed cortical network, the ventral processing stream, during spatial cognition tasks, and addition of testosterone improves spatial cognition in younger and older hypogonadal men. In addition, reduced testosterone is associated with depressive disorders. The relationship between depression and testosterone appears to partly depend upon the androgen receptor genotype of the patient, and in appropriate patients with low testosterone levels, testosterone substitution can increase positive mood and decrease negative mood. The much publicized link between testosterone and aggression is probably only of importance in athletes who supplement their testosterone levels to excessively high levels, whereas in hypogonadal men, testosterone supplementation only enhances the positive aspects of aggression such as vigour and energy. Current data suggest that testosterone supplementation in hypogonadal men of all ages will enhance many aspects of mood and cognition.     

LOH–pitfalls of an ambiguous abbreviation

Osteoporosis in elderly men is becoming an important health issue with the aging society. Elderly men with androgen deficiency are exposed to osteoporosis and can be treated with testosterone replacement. In this study, Eurycoma longifolia (EL), a plant with androgenic effects, was supplemented to an androgen-deficient osteoporotic aged rat as alternative to testosterone. Aged 12 months old Sprague-Dawley rats were divided into groups of normal control (NC), sham-operated (SO), orchidectomised-control (OrxC), orchidectomised and supplemented with EL (Orx?+?El) and orchidectomised and given testosterone (Orx?+?T). After 6 weeks of treatment, serum osteocalcin, serum terminal C-telopeptide Type 1 collagen (CTX) and the fourth lumbar bone calcium were measured. There were no significant differences in the osteocalcin levels before and after treatment in all the groups. The CTX levels were also similar for all the groups before treatment. However, after treatment, orchidectomy had caused significant elevation of CTX compared to normal control rats. Testosterone replacements in orchidectomised rats were able to prevent the rise of CTX. Orchidectomy had also reduced the bone calcium level compared to normal control rats. Both testosterone replacement and EL supplementation to orchidectomised rats were able to maintain the bone calcium level, with the former showing better effects. As a conclusion, EL prevented bone calcium loss in orchidectomised rats and therefore has the potential to be used as an alternative treatment for androgen deficient osteoporosis.     

Testosterone deficiency and the metabolic syndrome

Evidence is presented to link components of the metabolic syndrome to testosterone deficiency and obesity. Testosterone deficiency in hypogonadism or testosterone deprivation in normo-gonadotropic men increases fat mass as well as fasting insulin levels. Testosterone supplementation (TS) in a dose dependent manner, increase lean body mass (LBM), reduces fat mass, body mass index (BMI) and waist hip ratio in both young and elderly hypogonadal men. A negative association between T and insulin resistance as well as impaired glucose intolerance has been demonstrated and in type 2 diabetic men TS improves metabolic parameters. TS improves most components of the metabolic syndrome and also reduces inflammatory cytokines.     

How to help the aging male? Current approaches to hypogonadism in primary care

Hypogonadism is a common condition which occurs more frequently in older men. It is characterized by low testosterone (T) and is associated with symptoms which are often nonspecific. A key symptom is low libido, but it can also be associated with erectile dysfunction, reduced muscle mass and strength, increased body fat, reduced bone mineral density and osteoporosis, reduced vitality, and depressed mood. Hypogonadism is linked with a variety of comorbid conditions including erectile dysfunction, metabolic syndrome, diabetes, obesity, and osteoporosis. However, the condition is often underdiagnosed. T supplementation in hypogonadism is associated with a range of benefits including improved sexual function, increased lean body mass and/or reduced fat mass, and improved bone mineral density. A variety of T supplementation formulations are available. Although there is no evidence of increased risk of initiating prostate cancer with T supplementation, it is contraindicated in men with prostate cancer. It is important that primary care physicians are aware of both the signs and symptoms of hypogonadism, the monitoring and testing that is required and the merits and advantages of the various T preparations to ensure optimal management of the condition with a treatment approach that best suits patients’ needs.     

The relationship between circulating testosterone and inflammatory cytokines in men

Testosterone is the predominant gonadal androgen in men. Low testosterone levels are found to be associated with an increased in metabolic risk and systematic inflammation. Since adipose tissue is a source of inflammatory cytokines, testosterone may regulate inflammation by acting on adipose tissue. This review aimed to explore the role of testosterone in inflammation and its mechanism of action. Both animal studies and human studies showed that (1) testosterone deficiency was associated with an increase in pro-inflammatory cytokines; (2) testosterone substitution reduced pro-inflammatory cytokines. The suppression of inflammation by testosterone were observed in patients with coronary artery disease, prostate cancer and diabetes mellitus through the increase in anti-inflammatory cytokines (IL-10) and the decrease in pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α). Despite these, some studies also reported a non-significant relationship. In conclusion, testosterone may possess anti-inflammatory properties but its magnitude is debatable. More evidence is needed to validate the use of testosterone as a marker and in the management of chronic inflammatory diseases.     

The use of selective estrogen receptor modulators on bone health in men

Selective estrogen receptor modulators (SERMs) represent a class of drugs that act as agonist or antagonist for estrogen receptor in a tissue-specific manner. The SERMs drugs are initially used for the prevention and treatment of osteoporosis in postmenopausal women. Bone health in prostate cancer patients has become a significant concern, whereby patients undergo androgen deprivation therapy is often associated with deleterious effects on bone. Previous preclinical and epidemiological findings showed that estrogens play a dominant role in improving bone health as compared to testosterone in men. Therefore, this evidence-based review aims to assess the available evidence derived from animal and human studies on the effects of SERMs on the male skeletal system. The effects of SERMs on bone mineral density (BMD)/content (BMC), bone histomorphometry, bone turnover, bone strength and fracture risk have been summarized in this review.     

Oral testosterone undecanoate (Andriol®) supplement therapy improves the quality of life for men with testosterone deficiency

In a single-blind, placebo-controlled study, the effects of a 3-month oral administration of 160 mg/day testosterone undecanoate (Andriol^®) on the quality of life of men with testosterone deficiency were evaluated. The subjects included ten men with primary hypogonadism and 29 with andropause with sexual dysfunction as the most common problem. The changes in subjective symptoms were evaluated by the PNUH QoL scoring system and the St. Louis University Questionnaire for androgen deficiency in aging males (ADAM). Digital rectal examination (DRE) was performed and serum testosterone, prostate-specific antigen (PSA) and liver profile were monitored. Testosterone undecanoate treatment (n = 33) significantly improved sexual dysfunction and symptom scores of metabolic, cardiopulmonary, musculo-skeletal and gastrointestinal functions compared to baseline and to placebo (n = 6). ADAM score also significantly improved after 3 months of treatment. Serum testosterone was significantly increased compared to pretreatment levels only in the testosterone undecanoate group. In the placebo group, no significant changes compared to baseline were found for testosterone levels and QoL questionnaires. No abnormal findings were detected on DRE or laboratory findings in either group. Adverse events, such as gastrointestinal problems and fatigue, were mild and self-limiting. It is concluded that androgen supplement therapy with oral testosterone undecanoate (Andriol) restores the quality of life through improvement of general body functions in men with testosterone deficiency.     

Speaker abstracts

Purpose: There is no consensus on possible benefits and risks of testosterone supplementation. Here we review various controlled studies of testosterone supplementation in aging males.

Methods: We performed a PubMed search using the terms “testosterone/therapeutic use” with the limits “>65 years of age”, “randomized controlled clinical trials”, and “male gender”, starting in 1999.

Results: Forty-three articles have been published since 1999. Some of these studies also included patients in middle-age or younger. Findings reported in these articles were not entirely consistent. After weighting studies by the number of patients, hints are found that testosterone supplementation increases bone mass, lean body mass, muscle mass and hematopoiesis, and improves sexual functioning and perhaps mood, but does not affect serum lipids, cardiovascular parameters, prostate-specific antigen level, or cognition. Considering studies including only men older than 65 years, and in which testosterone supplements were compared with placebo treatment, slightly different results are obtained. In these patient groups, testosterone does not improve sexual function or mood.

Conclusion: The overall benefit of testosterone supplementation for the aging male remains unclear. Any supplementation in men with age-normal testosterone levels only on grounds of subjective symptoms is not advisable.     

Osteoporosis in the aging population: the male perspective

The importance of senile osteoporosis in men as a public health problem has long been underestimated. Elderly men are at substantial risk for fracture, and morbidity after osteoporotic fractures appears to be more serious and mortality more common in men than in women. Risk factors for osteoporotic fractures in men appear to be qualitatively similar to those in women, but there are quantitative differences. Low bone mineral density (BMD) is an important risk factor for fracture in men; however, further clarification of the relationship between BMD, bone geometry and fracture risk is needed before formulating definitive proposals on operational densitometric criteria for diagnosis of osteoporosis in men and the identification of men at high risk for fracture. Understanding of the mechanisms underlying senile bone loss and the pathogenesis of senile osteoporosis in men remains fragmentary with, in particular, the need for further clarification regarding the precise impact of hormonal status in elderly men on skeletal homeostasis. Recommendations on prevention and treatment of senile osteoporosis in men should focus on the minimization of known risk factors for bone loss and falls. Testosterone treatment may be useful in those men with initially low serum testosterone. As to other pharmacological treatment modalities, prospective trials specifically in elderly men, and preferably with fracture incidence as the primary clinical endpoint, are required.     

An audit of testosterone measurement in men attending with impotence

As part of the routine assessment of 185 unselected men with undiagnosed impotence, testosterone was measured on a single serum sample to try to detect a subset of men with androgen deficiency who might benefit from testosterone replacement therapy. Those with low levels of testosterone were investigated further with repeat measurements of testosterone and luteinizing hormone (LH). In addition, prostatic specific antigen (PSA) was measured in all the men to exclude concomitant prostate cancer. Testosterone replacement therapy was offered to 20 men with consistently low levels of the hormone but few of the men continued with the therapy because of lack of benefit. It was concluded that either testosterone deficiency is rare in unselected men who actually seek help for impotence orebe our protocol of androgen assessment was not helpful for this group of men. There was correlation between PSA results and testosterone and this may have implications for the investigation of prostate cancer. The results presented here are an audit of a clinical practice and call into question the benefit of routine testosterone measurement in the investigation of all men complaining of impotence.     

Visceral obesity,androgens and the risks of cardiovascular disease and diabetes mellitus

The sex difference in cardiovascular morbidity is traditionally ascribed to the effects of testosterone on the lipid profile. Epidemiological studies show, however, that men with cardiovascular disease have low rather than high circulating testosterone. The factor responsible for both the higher prevalence of cardiovascular disease and the low testosterone might be visceral obesity. Men and women differ in their pattern of fat distribution. Women have predominantly gluteofemoral fat depots and men preferential abdominal/visceral depots. In puberty testosterone favors abdominal/visceral fat deposition. Visceral fat has a high metabolic turnover and the free fatty acids drain on the portal vein. With a large visceral fat depot the liver is flooded with free fatty acids inducing high levels of triglycerides and low high-density lipoprotein cholesterol, impairment of insulin metabolism and reducing insulin sensitivity. These factors contribute to the development of cardiovascular disease and diabetes type II. High insulin levels suppress sex hormone-binding globulin thus lowering circulating testosterone. The fat cell produces leptin signalling to the brain to reduce food intake and increase energy expenditure. High leptin levels suppress testosterone. Some studies suggest that testosterone supplementation reduces visceral obesity and improves cardiovascular risks but more evidence is needed.     

Hypogonadotrophic hypogonadism in type 2 diabetes

Recent work shows a high prevalence of low testosterone and inappropriately low luteinizing hormone (LH) and follicle stimulating hormone (FSH) concentrations in type 2 diabetes. This syndrome of hypogonadotrophic hypogonadism (HH) is associated with obesity in patients with type 2 diabetes. However, the duration of diabetes or HbA1c are not related to HH. Furthermore, recent data show that HH is not associated with type 1 diabetes. C-reactive protein concentrations have been shown to be elevated in patients with HH and are inversely related to plasma testosterone concentrations. This inverse relationship between plasma free testosterone and C- reactive protein concentrations in patients with type 2 diabetes suggests that inflammation may play an important role in the pathogenesis of this syndrome. This is of interest since inflammatory mechanisms may have a cardinal role in the pathogenesis of insulin resistance. It is also relevant that in the mouse, deletion of the insulin receptor in neurons leads to HH in addition to a state of systemic insulin resistance. It has also been shown that insulin facilitates the secretion of gonadotrophin releasing hormone (GnRH) from neuronal cell cultures. Thus, HH may be the result of insulin resistance at the level of the GnRH secreting neuron. Low testosterone concentrations are also related to an increase in total and regional adiposity. This review discusses these issues and attempts to make the syndrome relevant as a clinical entity. Clinical trials are required to determine whether testosterone replacement alleviates insulin resistance and inflammation. In addition, low testosterone levels are associated with an increase in cardiovascular events. Testosterone therapy may therefore, reduce cardiovascular risk. This important aspect requires further investigation.     

Testofen,a specialised Trigonella foenum-graecum seed extract reduces age-related symptoms of androgen decrease,increases testosterone levels and improves sexual function in healthy aging males in a double-blind randomised clinical study

This study examined the effect of Testofen, a specialised Trigonella foenum-graecum seed extract on the symptoms of possible androgen deficiency, sexual function and serum androgen concentrations in healthy aging males. This was a double-blind, randomised, placebo-controlled trial involving 120 healthy men aged between 43 and 70 years of age. The active treatment was standardised Trigonella foenum-graecum seed extract at a dose of 600?mg/day for 12 weeks. The primary outcome measure was the change in the Aging Male Symptom questionnaire (AMS), a measure of possible androgen deficiency symptoms; secondary outcome measures were sexual function and serum testosterone. There was a significant decrease in AMS score over time and between the active and placebo groups. Sexual function improved, including number of morning erections and frequency of sexual activity. Both total serum testosterone and free testosterone increased compared to placebo after 12 weeks of active treatment. Trigonella foenum-graecum seed extract is a safe and effective treatment for reducing symptoms of possible androgen deficiency, improves sexual function and increases serum testosterone in healthy middle-aged and older men.     

Three-year follow-up of androgen treatment in hypogonadal men: preliminary report with testosterone gel

Transdermal testosterone gels represent an effective alternative to injectable testosterone preparations. Shortterm (6 months) data demonstrated positive effects on muscle, bone, fat, libido and mood. This report provides a preliminary analysis of longer-term treatment with a testosterone gel (AndroGel ? or Testogel®) in a group of men aged 19-67 years of age. The positive effects of testosterone treatment on all of the above parameters persisted in this 3-year follow-up. The benefits occurred independent of age (equally in the older and younger subjects). The positive effects of transdermal testosterone gel on bone mineral density previously identified at 6 months of treatment, continued with time. The positive effects on bone mineral density were greater in the spine than the hip. There were minimal effects on lipid levels. Levels of prostate-specific antigen (PSA) increased with testosterone treatment but, in general, remained in the normal range. Three subjects (1.8%) were shown to have elevated PSA and biopsy-proven prostate cancer. It was not possible to determine if this incidence is above the background rate. Monitoring for prostate disease through PSA measurements and digital rectal examination is recommended for hypogonadal men in the older age groups when treated with testosterone.     

Effect of testosterone therapy on lumbar spine and hip mineral density in elderly men

Objective.?The aim of the present study was to analyse the effect of testosterone therapy on bone mineral density in healthy elderly men who had low levels of total testosterone.

Design.?Randomized, double-blind, placebo-controlled study.

Participants.?Forty-eight men over 60 years old with decreased testosterone levels (≤320 ng/dL) comprised the study. Twenty-five out of 48 received intramuscular injections of testosterone enanthate every three weeks during 12 months; the remaining 23 participants formed the control group. All participants had measurements of bone mineral density (BMD) in both lumbar spine and hip before and at the end of the study as well as testosterone and 17-β estradiol levels.

Results:?Testosterone treated group exhibited a significant (p < 0.05) increment (from 1.198 ± 0.153 to 1.240 ± 0.141 g/cm²) in lumbar BMD in parallel with a significant (p < 0.001) increment (from 301 ± 32 to 471 ± 107 ng/dL) in testosterone concentrations, whereas no significant change occurred in femoral neck BMD.

Conclusions.?Testosterone therapy elicited a positive effect only in lumbar BMD in elderly men with diminished testosterone serum levels.