Andropause: a quality-of-life issue in older males

The Prevalence of Andropause and Its Relationship With Sexual Quality of Life Among Older Iranian Men

Available evidence indicates insufficient knowledge about the status of andropause and sexual quality of life among Iranian older men. The study aimed to investigate the prevalence of andropause and its relationship with sexual quality among older adults. This descriptive-analytical study was conducted among 576 older people referred to urban health centers in Mashhad, Iran. The eligible samples were selected through the cluster sampling method. To collect data, the male andropause symptoms' self-assessment questionnaire and the sexual quality of life-male were used. Forty-seven of the respondents (n = 271) were diagnosed with a "moderate" level of andropause. A strong negative correlation was identified between the sexual quality of life and the severity of andropause (r = -.366, p < .001). Sexual quality of life and andropause was also affected by age, marital status, health status, and exercise. Thirty-six percent of the changes in the quality of sexual life of older men were influenced by the independent variables (adjusted R² = .36; R² = .40; R = .63). The findings indicated that andropause has highly prevailed among the participants. There was a meaningful association between andropause and sexual quality of life among older men. Further studies are recommended to investigate sexual orientation qualitatively and to discover other factors influencing andropause among adult men.

Prevalence of andropause among Iranian men and its relationship with quality of life

INTRODUCTION

Andropause is a complicated process in men's life which can negatively affect their quality of life in both physical and psychological dimensions.

OBJECTIVES

The aim of this study was to determine the prevalence of andropause among Iranian men age 40-85 years and its relationship with quality of life.

MATERIALS AND METHODS

This was a cross-sectional study among 393 men attending ten urban healthcare centers in Ilam province in southwestern Iran. Study participants were recruited using proportional random sampling. The Male andropause symptoms self-assessment questionnaire (MASSQ) and SF-12 were used for data collection. Data were analyzed using SPSS version 22 (Chicago, IL).

RESULTS

The mean (SD) of participants scores in MASSQ was 57.46 (17.56). Only 61 (15.5%) men were classified at "don't need testosterone" category based on MASSQ. There were significant associations between the eight aspects of HRQoL and the andropause severity (p < .001). Older age, lower education, having depression, coronary heart disease, and incontinence were associated with increased odds of andropause (p < .05).

CONCLUSION

This study confirmed findings of previous studies regarding andropause and its relationship with men's quality of life. Future studies in this topic are needed to discover all the factors that may influence men andropause.

MR-10 Enhances Men's Health by Improving Endogenous Male Sex Hormone Generation

Although there is a clear need for improving men's health, treatment with suitable natural substances has not yet been well established. Previously, it was reported that MR-10, a novel complex of Korean dandelion and rooibos found by screening many natural products, improved sperm generation and activity. Here, the ability of MR-10 to increase testosterone levels and enhance men's health was tested. Treatment with MR-10 (400 mg/day) for a month significantly increased levels of free testosterone, total testosterone, and the testosterone precursor dehydroepiandrosterone by 22%, 14%, and 32%, respectively, in clinical studies. Also, men's health in terms of mental, physical, and sexual aspects, as determined by using the clinical questionnaires Androgen Deficiency of Aging Men and Aging Males' Symptoms, was improved. Furthermore, the safety of MR-10 was determined by testing levels of prostate-specific antigen, glutamic oxaloacetic transaminase, and glutamic pyruvate transaminase; and the lack of changes due to MR-10 treatment supports the safety of MR-10. In conclusion, this study suggests that MR-10 is a safe and effective natural product improving men's sexual health.

Testosterone supplementation, glucocorticoid milieu and bone homeostasis in the ageing male

Male ageing is entwined with a continuous fall in free testosterone levels, which contributes to the pathogenesis of bone loss. Glucocorticoid excess, either dependent on the ageing process or iatrogenically induced, was found to additionally impair the bone structure and metabolism. Cautious testosterone supplementation in this respect may positively affect the glucocorticoid milieu and bone homeostasis, while testosterone-induced changes in the glucocorticoid output could serve as a determinant of bone-related therapeutic outcome. Namely, bone mineral content/density, the parameters of trabecular bone structure as well as bone strength are enhanced, serum calcitonin levels tend to increase, while serum osteocalcin, serum parathyroid hormone and urinary calcium decrease, all upon testosterone administration to the ageing male. In parallel, testosterone application decreases glucocorticoid secretion in the animal models of male ageing, while clinical data in this field are still inconsistent. Importantly, a physiological link exists between testosterone-induced changes in glucocorticoid levels and the tendency of bone status improvement in the ageing male. We believe that the assessment of circulating adrenocorticotropic hormone concentrations together with glucocorticoid levels, reflecting the hypothalamic-pituitary-adrenal axis feedback loop operativeness during testosterone supplementation, represents a well-balanced bone-related therapeutic update.

Frailty and sarcopenia in elderly

Frailty is a pre-disability syndrome where an older person can be identified as being at risk when exposed to stressors associated with high risk for disability or needing to be hospitalized. Two major frailty definitions exist. The physical phenotype of frailty and the multiple deficit model. A simple frailty screening tool-FRAIL-has been validated. Treatment of frailty involves resistance exercise, optimization of nutrition, and treatment of fatigue (sleep apnea, depression), treatable causes of weight loss and adjustment of polypharmacy. Sarcopenia (decline in function with low muscle mass) is a major cause of frailty. A simple sarcopenia screening tool-SARC-F-has been validated. The multiple causes of sarcopenia are reviewed. Optimal treatment is resistance exercise, leucine-enriched essential amino acids and vitamin D replacement.

Testosterone application decreases the capacity for ACTH and corticosterone secretion in a rat model of the andropause

The culminating phase of ageing in males-andropause is characterized by enhanced activity of the hypothalamic-pituitary-adrenal axis and frequent glucocorticoid excess. In parallel, free testosterone deficiency provides the baseline hormonal milieu for the ageing male. The aim of this study was to illustrate (using diverse microscopic and biochemical methodologies) the effects of testosterone application on the capacity for adrenocorticotropic hormone (ACTH) and corticosterone secretion in a rat model of the andropause. Middle-aged Wistar rats were divided into sham-operated (SO; n=8), orchidectomized (Orx; n=8) and testosterone treated orchidectomized (Orx+T; n=8) groups. Testosterone propionate (5 mg/kg b.w./day) was administered for three weeks, while SO and Orx groups received the vehicle alone. ACTH cells and the adrenal cortex were stained using immuno-histochemical, immuno-fluorescent and histochemical procedures. Circulating concentrations of testosterone, estradiol, ACTH and corticosterone, as well as the adrenal tissue corticosterone levels were measured by immunoassays. Testosterone application led to increased (p<0.05) serum concentrations of sex steroids. Consequently, in Orx+T rats the ACTH cell nuclei volume increased (p<0.05) by 34%, while the volume density of ACTH cells and their relative intensity of fluorescence decreased (p<0.05) by 46% and 21%, respectively, in comparison with the corresponding parameters in the Orx group. Testosterone also induced vasodilatation in the adrenocortical zona fasciculata, and decreased (p<0.05) the ACTH concentrations and adrenal tissue corticosterone levels by 38% and 31%, respectively, compared to the Orx group. In conclusion, testosterone administration caused a decrease in the capacity for ACTH and corticosterone secretion in a rat model of the andropause.

Testosterone deficiency and severity of erectile dysfunction are independently associated with reduced quality of life in men with type 2 diabetes

Erectile dysfunction (ED) and low testosterone levels are common in men with type 2 diabetes (T2D). We have investigated the impact of testosterone on quality of life (QoL) in diabetic men with ED. Men with ED were identified within a study cohort of 355 men with T2D. All subjects completed SF-36 health and Androgen Deficiency of the Aging Male questionnaires. Total tesosterone (TT), bioavailable testosterone (BT) and sex hormone-binding globulin levels of study participants were measured and free testosterone levels were calculated (cFT). A subgroup of 126 ED patients completed the International Index of Erectile Function-5 (IIEF-5) questionnaire. Linear regression analyses were corrected for age, body mass index (BMI), glycosylated haemoglobin (HbA1c), smoking, alcohol consumption and cardiovascular disease (CVD). Total SF-36 scores significantly and positively correlated with TT levels (r = 0.219, p = 0.001), BT levels (r = 0.199, p = 0.004) and cFT levels (r = 0.185, p = 0.007) among men with ED. These trends were strengthened after adjusting for age, BMI, HbA1c, smoking, alcohol consumption and CVD (TT r = 0.359, p = 0.015; BT r = 0.354, p = 0.024 and cFT r = 0.354, p = 0.024). IIEF-5 scores significantly correlated inversely with TT (r = 0.546, p = 0.001), BT (r = 0.506, p = 0.004) and cFT levels (r = 0.532, p = 0.001). A positive linear relationship was observed between IIEF-5 scores and total SF-36 score (r = 0.491, p = 0.003). Patients who reported having ED had an average SF-36 score of 9.1% less than those without ED (p < 0.001). Lower testosterone and greater severity of ED independently correlated with poorer physical function, social function, vitality and decline in general health domains of the SF-36. This is the first study to report that testosterone deficiency and severity of ED are both independently associated with reduced QoL in men with T2D. Furthermore, ED and low testosterone are markers of poor health which impact on an individual's self-perception of their health status.

Testosterone level and the effect of levodopa and agonists in early Parkinson disease: results from the INSPECT cohort

Background

To determine if testosterone levels are influenced by dopaminergic therapy in Parkinson disease (PD) patients. Testosterone level has been reported to be low in patients with PD and other neurodegenerative diseases. In this study, we sought to determine whether dopaminergic therapy (i.e. levodopa and dopamine agonist) influenced testosterone levels. We used a cohort of consecutive male patients from the INSPECT trial--a multi-center, prospective, study that primarily investigated the effects of short-term treatment with pramipexole or levodopa on [¹²³I] B-CIT SPECT imaging in early PD.

Methods

Testosterone levels were drawn on consenting male subjects with early PD who enrolled in the INSPECT trial at three study visits (baseline, 12 weeks post-treatment, and 8–12 weeks post-washout). Subjects were randomized to: no treatment, pramipexole (up to 3 mg) or levodopa (up to 600 mg). Testosterone levels were obtained twice (prior to 10 AM) and averaged for each of three study visits.

Results

Thirty two male patients participated in this sub-study and there were no significant differences in disease characteristics in the 3 groups at baseline. Twenty-nine patients completed the follow-up visits and were suitable for analysis. There were statistically significant differences in the change in free testosterone level, increased in both the levodopa group and pramipexole group but decreased in the untreated group at 12-weeks post-treatment. There were no significant differences in the changes of UPDRS total or motor scores, although there was a strong trend toward improvement in motor scores. The testosterone level persisted in its increase only in the pramipexole group at the end of the washout period.

Conclusion

These preliminary data support the premise that dopaminergic medications do not reduce testosterone levels in early PD patients.

Electronic supplementary material

The online version of this article (doi:10.1186/2054-7072-1-8) contains supplementary material, which is available to authorized users.

The Interplay between Magnesium and Testosterone in Modulating Physical Function in Men

The role of nutritional status as key factor of successful aging is very well recognized. Among the different mechanisms by which nutrients may exert their beneficial effects is the modulation of the hormonal anabolic milieu, which is significantly reduced with aging. Undernutrition and anabolic hormonal deficiency frequently coexist in older individuals determining an increased risk of mobility impairment and other adverse outcomes. Mineral assessment has received attention as an important determinant of physical performance. In particular, there is evidence that magnesium exerts a positive influence on anabolic hormonal status, including Testosterone, in men. In this review we summarize data from observational and intervention studies about the role of magnesium in Testosterone bioactivity and the potential underlying mechanisms of this relationship in male subjects. If larger studies will confirm these pivotal data, the combination of hormonal and mineral replacements might be adopted to prevent or delay the onset of disability in the elderly.

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.

Effect of long-acting testosterone undecanoate treatment on quality of life in men with testosterone deficiency syndrome: a double blind randomized controlled trial

This study aimed to investigate the effect of intramuscular injection of testosterone undecanoate on overall quality of life (QoL) in men with testosterone deficiency syndrome (TDS). A randomized controlled trial over a 12-month period was carried out in 2009. One hundred and twenty men aged 40 years and above with a diagnosis of TDS (serum total testosterone <12 nmol l(-1) and total Aging Male Symptom (AMS) scores ≥27) were invited to participate. Interventions comprised intramuscular injection of either placebo or 1000 mg testosterone undecanoate, given at weeks 0, 6, 18, 30 and 42. This paper presents the secondary analysis of QoL changes measured in the scores of Short-Form-12 (SF-12) scale at baseline, weeks 30 and 48 after the first injection. A total of 56/60 and 58/60 men from the active treatment and placebo group, respectively, completed the study. At week 48, before adjusting for baseline differences, the QoL of men in the treatment group improved significantly in five out of the eight domains on SF-12. The physical health composite scores improved 4.0 points from a baseline of 41.9±7.0 in the treatment group compared to 0.8 point from a baseline of 43.7±7.1 in the placebo group (F=3.652, P=0.027). The mental health composite scores improved 4.4 points from a baseline of 37.1±9.0 in the treatment group compared to 1.0 points from a baseline of 37.6±7.9 in the placebo group (F=4.514, P=0.018). After adjusting for baseline differences, significant improvement was observed in mental health composite scores, but not in physical health composite scores. Long-acting testosterone undecanoate significantly improved the mental health component of QoL in men with TDS.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Sex hormones, aging, and Alzheimer's disease

A promising strategy to delay and perhaps prevent Alzheimer's disease (AD) is to identify the age-related changes that put the brain at risk for the disease. A significant normal age change known to result in tissue-specific dysfunction is the depletion of sex hormones. In women, menopause results in a relatively rapid loss of estradiol and progesterone. In men, aging is associated with a comparatively gradual yet significant decrease in testosterone. We review a broad literature that indicates age-related losses of estrogens in women and testosterone in men are risk factors for AD. Both estrogens and androgens exert a wide range of protective actions that improve multiple aspects of neural health, suggesting that hormone therapies have the potential to combat AD pathogenesis. However, translation of experimental findings into effective therapies has proven challenging. One emerging treatment option is the development of novel hormone mimetics termed selective estrogen and androgen receptor modulators. Continued research of sex hormones and their roles in the aging brain is expected to yield valuable approaches to reducing the risk of AD.

Sex hormones, aging, and Alzheimer's disease

A promising strategy to delay and perhaps prevent Alzheimer's disease (AD) is to identify the age-related changes that put the brain at risk for the disease. A significant normal age change known to result in tissue-specific dysfunction is the depletion of sex hormones. In women, menopause results in a relatively rapid loss of estradiol and progesterone. In men, aging is associated with a comparatively gradual yet significant decrease in testosterone. We review a broad literature that indicates age-related losses of estrogens in women and testosterone in men are risk factors for AD. Both estrogens and androgens exert a wide range of protective actions that improve multiple aspects of neural health, suggesting that hormone therapies have the potential to combat AD pathogenesis. However, translation of experimental findings into effective therapies has proven challenging. One emerging treatment option is the development of novel hormone mimetics termed selective estrogen and androgen receptor modulators. Continued research of sex hormones and their roles in the aging brain is expected to yield valuable approaches to reducing the risk of AD.

Rheumatoid cachexia and cardiovascular disease

Both cachexia and cardiovascular disease are strongly associated with rheumatoid arthritis (RA) and linked to the chronic inflammatory process. Typically, rheumatoid cachexia occurs in individuals with normal or increased BMI (reduced muscle mass and increased fat mass). Classic cachexia (reduced muscle mass and reduced fat mass) is rare in RA but is associated with high inflammatory activity and aggressive joint destruction in patients with a poor cardiovascular prognosis. Conversely, obesity is linked to hypertension and dyslipidemia but, paradoxically, lower RA disease activity and less cardiovascular disease-related mortality. Rheumatoid cachexia might represent the 'worst of both worlds' with respect to cardiovascular outcome, but until diagnostic criteria for this condition are agreed upon, its effect on cardiovascular disease risk remains controversial.

Evaluation and management of osteoporosis and fragility fractures in the elderly

Osteoporosis is characterized by low bone mass and microarchitectural deterioration that leads to increased bone fragility and fracture. The medical, psychosocial and economic burden that fragility fractures have on individuals and society is staggering. As the geriatric segment of the population continues to expand, so to will the magnitude of this epidemic. There are multiple mechanisms influencing bone quality and bone loss with age. Fragility fracture is a composite of multiple intrinsic and extrinsic factors related to the individual and their environment. Fall prevention remains the cornerstone of management in this problem. The FRAX® fracture risk assessment program, which estimates the 10-year probability of a major osteoporotic fracture, is an exciting new tool in assessing risk. Novel therapeutics, including zoledronic acid, strontium and teriparatide, are now available to complement proven osteoporosis treatments and more effectively decrease fracture risk in vulnerable individuals. Agents in Phase III trials, including denosumab and lasofoxifene, will probably increase the armamentarium of tools clinicians can use to combat the growing problem of osteoporosis and its complications.

Risk of late-onset hypogonadism (andropause) in Brazilian men over 50 years of age with osteoporosis: usefulness of screening questionnaires

OBJECTIVE

To analyze the relative risk of late-onset hypogonadism in men with osteoporosis and the usefulness of screening questionnaires.

METHODS

We correlated the Aging Male's Symptoms (AMS), Androgen Deficiency in Aging Male (ADAM) and International Index of Erectile Function (IIEF-5) questionnaires and the laboratory diagnosis of hypogonadism in 216 men aged 50-84 years (110 with osteoporosis and 106 with normal bone density, paired by age and ethnicity).

RESULTS

Hypogonadism presented in 25% of the osteoporotic and in 12.2 % of normal bone density men (OR 2.08; IC95%: 1.14-3.79) and was associated with ADAM first question (low libido, p=0.013). Levels of TT below 400 ng/dl correlated with an AMS score above 26 (p=0.0278). IIEF-5 showed no correlation with testosterone levels.

CONCLUSION

Hypogonadism was 2.08 times more prevalent in osteoporotic men. The symptom that best correlated with late-onset hypogonadism was low libido (ADAM 1 positive).

Protective actions of sex steroid hormones in Alzheimer's disease

Risk for Alzheimer's disease (AD) is associated with age-related loss of sex steroid hormones in both women and men. In post-menopausal women, the precipitous depletion of estrogens and progestogens is hypothesized to increase susceptibility to AD pathogenesis, a concept largely supported by epidemiological evidence but refuted by some clinical findings. Experimental evidence suggests that estrogens have numerous neuroprotective actions relevant to prevention of AD, in particular promotion of neuron viability and reduction of beta-amyloid accumulation, a critical factor in the initiation and progression of AD. Recent findings suggest neural responsiveness to estrogen can diminish with age, reducing neuroprotective actions of estrogen and, consequently, potentially limiting the utility of hormone therapies in aged women. In addition, estrogen neuroprotective actions are also modulated by progestogens. Specifically, continuous progestogen exposure is associated with inhibition of estrogen actions whereas cyclic delivery of progestogens may enhance neural benefits of estrogen. In recent years, emerging literature has begun to elucidate a parallel relationship of sex steroid hormones and AD risk in men. Normal age-related testosterone loss in men is associated with increased risk to several diseases including AD. Like estrogen, testosterone has been established as an endogenous neuroprotective factor that not only increases neuronal resilience against AD-related insults, but also reduces beta-amyloid accumulation. Androgen neuroprotective effects are mediated both directly by activation of androgen pathways and indirectly by aromatization to estradiol and initiation of protective estrogen signaling mechanisms. The successful use of hormone therapies in aging men and women to delay, prevent, and or treat AD will require additional research to optimize key parameters of hormone therapy and may benefit from the continuing development of selective estrogen and androgen receptor modulators.

Awareness and knowledge of andropause among Chinese males in Hong Kong

This is a pilot study that explored the awareness and knowledge of andropause among Chinese males in Hong Kong. The study employed a structured questionnaire and a convenience sample of 500 individuals at the age > or =40 years participated in the survey. A total of 397 (79.4%) of the respondents were identified as andropause-enlightened, 88.2% of whom believed that andropause was a natural aging process. Mass media was the main source of andropausal information. The andropause-enlightened respondents had poor knowledge with the mean knowledge score of 5.94. The majority identified irritability (72.5%), loss of energy (66.5%), and loss of libido (60.7%) as symptoms. Less than half of the andropause-enlightened respondents expressed that andropause could be treated and only 34 knew testosterone replacement therapy as a treatment. The present findings underscore the need for provision of health education to increase the knowledge of andropause among adult males.

Sarcopenia in nursing home residents

The age-associated loss of muscle mass and muscle strength described by the term sarcopenia is highly relevant for functionality among nursing home residents. Nevertheless, the scientific literature concentrating on sarcopenia in this population is scarce. For practical reasons, common definitions of this entity, which rely on dual energy x-ray absorptiometry (DEXA) and bioimpedance analysis (BIA), cannot be applied in this setting. Anthropometric measurements like arm muscle circumference and calf circumference seem to be most suitable. Handgrip may be used as an alternative. Prevalence data show a wide range but are mostly high. There is a close association of the degree of sarcopenia with dependence among residents. The pathophysiology of sarcopenia in this population is strongly influenced by comorbidity and often there is significant overlap with the cachexia syndrome. At present, physical exercise is regarded to be the most promising therapeutic option, with resistance training being superior to endurance programs. Physical exercise has been successful even among Alzheimer patients and physically restrained residents. It has to be accompanied by the provision of adequate and diverse meals based on individual energy and nutrient requirements. Special attention should be paid to the treatment of vitamin D deficiency if present. New therapeutic options include Whole Body Vibration, oral supplements with essential amino acids and leucine, ACE-inhibitors, and cytokine-modifying drugs.

Testosterone supplementation for hypogonadal men by the nasal route

Although multiple forms of testosterone replacement therapy are available to treat hypogonadism, none is ideal. This article reports on the pharmacokinetics of an innovative nasal formulation of testosterone in hypogonadal men. The first study was undertaken in eight men with a baseline total testosterone (TT) of 130.8 +/- 87.4 ng/dL and examined the pharmacokinetics of nasal testosterone given in a single dose of 7.6 mg, 15.2 mg or 22.8 mg, respectively. The second study examined the pharmacokinetics of nasal testosterone (7.6 mg) given either twice or three times a day in 21 severely hypogonadal men (baseline TT in 20 patients <50 ng/dL, in one patient 152 ng/dL) for 14 days. The steady-state concentration of testosterone was within the normal range in all treatment groups, but only in the 3-times-a-day group was the 95% confidence interval completely within the physiological range. The average DHT level did not exceed the upper range of normal. The clinical global visual analogue scale improved in the whole group receiving testosterone (p < 0.001). All adverse events in both studies were of mild to moderate intensity and were evaluated as unlikely or not related to the administered study drug. No patients dropped out during treatment. Comparison with the normal circadian rhythm by computer modelling suggests that nasal testosterone can be used to mimic the normal diurnal pattern in eugonadal men. Thus, nasal testosterone can be administered safely to humans in doses that approximate serum concentrations in the normal physiological range.

Magnesium effect on testosterone-SHBG association studied by a novel molecular chromatography approach

A biochromatographic approach is developed to measure for the first time thermodynamic data and magnesium (Mg(2+)) effect for the binding of testosterone (TT) to sex hormone-binding globulin (SHBG) in a wide temperature range. For this, the SHBG was immobilized on a chromatographic support. It was established that this novel SHBG column was stable during an extended period of time. The affinity of TT to SHBG is high and changes slightly with the Mg(2+) concentration because the number of Mg(2+) linked to binding is low. The determination of the testosterone retention with the steroid hormone at different Mg(2+) concentrations and temperatures demonstrated that the Mg(2+) binding heat effect associated with this Mg(2+) release or uptake during this binding was in magnitude around 17kJ/mol corresponding to the model describing the electrostatic attraction that occurs between the negatively charged non specific areas of SHBG and the positively charged of magnesium. At all the magnesium concentrations studied, the DeltaH values were negative due to van der Waals interactions and hydrogen bonding which are engaged at the complex interface confirming strong TT-SHBG hydrogen bond networks. As well, the DeltaS values were all positive due to hydrophobic forces in the testosterone-SHBG complex formation. In addition our results suggest that adaptive conformational transitions contribute to the specific testosterone-SHBG complex formation. As well, in the biological Mg(2+) concentration domain, it was clearly demonstrated that there was an uncompetitive inhibition of Mg(2+) on TT-SHBG binding which led an enhancement of bioavailable TT. Our work indicated that our biochromatographic approach could soon become very attractive for study other SHBG-steroid (or phytoestrogen) binding.

The diagnosis of late life hypogonadism

The diagnosis of late life hypogonadism is controversial. For the purposes of discussion, it is suggested that treatment of late life hypogonadism requires the presence of symptoms, a low level of circulating free or bioavailable testosterone level and a positive response to treatment. While this may appear to be a radical proposal, we believe it represents the most rigorous scientific approach to the diagnosis of late life hypogonadism at the present time.

Neuroendocrine implications of opioid therapy

Opioid analgesics are given to people with pain. These medications are highly effective for relieving pain and are generally considered to have little or no end-organ toxi-cities. Although they are generally feared because of their potential for abuse, diversion, and psychological dependence, little attention is given to their neuroendocrine consequences. They are known to have central nervous systems effects and are now understood to impact the regulation of gonadotropic hormones. Providing meaningful informed consent requires disclosure about the risks associated with lowered gonadotropic hormone levels.