Testosterone and Frailty

Androgen Affects the Inhibitory Avoidance Memory by Primarily Acting on Androgen Receptor in the Brain in Adolescent Male Rats

Adolescence is the critical postnatal stage for the action of androgen in multiple brain regions. Androgens can regulate the learning/memory functions in the brain. It is known that the inhibitory avoidance test can evaluate emotional memory and is believed to be dependent largely on the amygdala and hippocampus. However, the effects of androgen on inhibitory avoidance memory have never been reported in adolescent male rats. In the present study, the effects of androgen on inhibitory avoidance memory and on androgen receptor (AR)-immunoreactivity in the amygdala and hippocampus were studied using behavioral analysis, Western blotting and immunohistochemistry in sham-operated, orchiectomized, orchiectomized + testosterone or orchiectomized + dihydrotestosterone-administered male adolescent rats. Orchiectomized rats showed significantly reduced time spent in the illuminated box after 30 min (test 1) or 24 h (test 2) of electrical foot-shock (training) and reduced AR-immunoreactivity in amygdala/hippocampal cornu Ammonis (CA1) in comparison to those in sham-operated rats. Treatment of orchiectomized rats with either non-aromatizable dihydrotestosterone or aromatizable testosterone were successfully reinstated these effects. Application of flutamide (AR-antagonist) in intact adolescent rats exhibited identical changes to those in orchiectomized rats. These suggest that androgens enhance the inhibitory avoidance memory plausibly by binding with AR in the amygdala and hippocampus.

Evolution of Guidelines for Testosterone Replacement Therapy

Testosterone is an essential hormone required for the developmental growth and maintenance of the male phenotype during the whole life. With the increasing male life expectancy worldwide and development of adequate testosterone preparations, the prescription of testosterone has increased tremendously. Testosterone replacement should be based on low serum testosterone and related clinical symptoms. In the last two decades, with the accumulation of data, official recommendations have evolved in terms of definition, diagnosis, treatment, and follow-up. In practice, it is better for physicians to follow the Institutional Official Recommendations or Clinical Practice Guideline for an adequate diagnosis and treatment of testosterone deficiency. Currently, four official recommendations are available for diagnosis and treatment of patients with testosterone deficiency. The inconsistencies in the guidelines merely create confusion among the physicians instead of providing clear information. Furthermore, there is no definite method to assess serum testosterone and clinical symptoms. In the era of active testosterone replacement therapy (TRT), physicians' practice patterns should be consistent with the clinical practice guidelines to avoid the misuse of testosterone. In this review, the author introduces the evolution of clinical guidelines to provide a comprehensive understanding of the differences and controversies with respect to TRT.

Testosterone level in aging male with different glucose tolerance state and its association with osteocalcin

OBJECTIVE

To investigate the relationship of testosterone and different glucose tolerance state, and its association with osteocalcin.

METHODS

A cross-sectional study was conducted of 1176 males aged 60-97 years who were arranged for an annual regular checkup from March to May 2012 in Chinese PLA general hospital in Beijing.

RESULTS

Individuals categorized as having prediabetes or diabetes were more likely to have lower osteocalcin, testosterone, and SHBG levels compared to those with normal glucose tolerance (p < .05 in males). In aging males, after adjusting for age, the negative association between osteocalcin and BMI, waist circumference, FPG, 2hPBG, or TG were significant. And serum TT was negatively associated with BMI, waist circumference, FPG, 2hPBG, or TG independent of age, ALP, Ca, P, VitD, and PTH.

CONCLUSIONS

It showed that serum osteocalcin and TT were closely related with BMI, blood glucose, and TG, which supported the hypothesis that regulation of bone remodeling, energy metabolism, and reproduction are linked.

Characteristics influencing high-risk sexual behaviours in elderly men

With the objective of investigating the characteristics influencing high-risk sexual behaviours in elderly men (60-74 years of age) in Chongqing, China, a total of 1433 healthy elderly men with sexual intercourse frequencies of one to six times/month who were willing to participate in the questionnaires were studied at four hospitals. We measured serum testosterone levels and performed follow-ups every six months, with a total of 1128 elderly men followed up after two years. We also investigated socio-economic and demographic characteristics (age, education, income, location, marital status and number of marriages), types of sexual partners, age differences with fixed sexual partners, frequency of sexual intercourse, combined basic age-related diseases, sexually transmitted infections (STIs) education, elderly self-care ability and high-risk sexual behaviours (frequency of sexual intercourse and number of sexual partners) using questionnaires. We analysed the influencing factors of high-risk sexual behaviours in elderly men using a univariate analysis, multivariate logistic regression analysis, BP neural network prediction and cluster analysis. Finally, we found that serum total testosterone, age, types of sexual partners, age differences with fixed partners and frequency of sexual intercourse are five factors that influence high-risk sexual behaviours in elderly men.

Everyday cognitive functioning and global cognitive performance are differentially associated with physical frailty and chronological age in older Chinese men and women

OBJECTIVES

Intact cognition is a key determinant of quality of life. Here, we investigated the relative contribution of age and physical frailty to global and everyday cognition in older adults.

METHODS

Data came from 1396 community-dwelling, healthy Chinese older adults aged 65 or above. We measured their global cognition using the Cantonese Chinese Montreal Cognitive Assessment, everyday cognition with the short Chinese Lawton Instrumental Activities Daily Living scale, and physical frailty using the Fatigue, Resistance, Ambulation, Illness, and Loss of Weight Scale and grip strength. Multiple regression analysis was used to evaluate the comparative roles of age and physical frailty.

RESULTS

In the global cognition model, age explained 12% and physical frailty explained 8% of the unique variance. This pattern was only evident in women, while the reverse (physical frailty explains a greater extent of variance) was evident in men. In the everyday cognition model, physical frailty explained 18% and chronological age explained 9% of the unique variance, with similar results across both genders.

CONCLUSION

Physical frailty is a stronger indicator than age for everyday cognition in both genders and for global cognition in men. Our findings suggest that there are alternative indexes of cognitive aging than chronological age.

Benefits and Health Implications of Testosterone Therapy in Men With Testosterone Deficiency

INTRODUCTION

Testosterone (T) deficiency (TD; hypogonadism) has deleterious effects on men's health; negatively affects glycometabolic and cardiometabolic functions, body composition, and bone mineral density; contributes to anemia and sexual dysfunction; and lowers quality of life. T therapy (TTh) has been used for the past 8 decades to treat TD, with positive effects on signs and symptoms of TD.

AIM

To summarize the health benefits of TTh in men with TD.

METHODS

A comprehensive literature search was carried out using PubMed, articles relevant to TTh were accessed and evaluated, and a comprehensive summary was synthesized.

MAIN OUTCOME MEASURES

Improvements in signs and symptoms of TD reported in observational studies, registries, clinical trials, and meta-analyses were reviewed and summarized.

RESULTS

A large body of evidence provides significant valuable information pertaining to the therapeutic value of TTh in men with TD. TTh in men with TD provides real health benefits for bone mineral density, anemia, sexual function, glycometabolic and cardiometabolic function, and improvements in body composition, anthropometric parameters, and quality of life.

CONCLUSION

TTh in the physiologic range for men with TD is a safe and effective therapeutic modality and imparts great benefits on men's health and quality of life. Traish AM. Benefits and Health Implications of Testosterone Therapy in Men With Testosterone Deficiency. Sex Med Rev 2018;6:86-105.

Association of perfluoroalkyl substances exposure with reproductive hormone levels in adolescents: By sex status

Polyfluoroalkyl substances (PFASs) are a group of common chemicals that ubiquitously exist in wildlife and humans. However, few studies have researched the effect of PFASs on reproductive hormones in adolescents. To provide information in this regard, we recruited 225 Taiwanese adolescents aged 13-15years from 2009 to 2010 to investigate the relationship between serum PFASs (PFOS, PFOA, PFBS, PFDA, PFDoA, PFHxA, PFHxS, PFNA and PFTA) and reproductive hormone concentrations using a cross-sectional study design. Results showed PFOS and PFTA levels were highest among the PFASs, with a median concentrations of 29.9 (interquartile range: 13.0-43.8) ng/mL and 6.0 (0.6-25.9) ng/mL in males, and a median concentrations of 28.8 (14.8-42.6) ng/mL and 4.5 (0.3-18.4) ng/mL in females. After adjustment for confounding factors, nonsignificant associations between PFASs and reproductive hormone were found except for PFNA with ln(estradiol) (β=0.2060, 95%CI: 0.0016, 0.4105). When stratified by sex, more significant associations were found in males than in females. Among males, PFASs were negatively associated with ln(testosterone) level for PFOS (β=-0.0029, 95%CI: -0.0055, -0.0003), PFDA (β=-0.2565, 95%CI: -0.4135, -0.0994), PFHxA (β=-0.3095, 95%CI: -0.5942, -0.0248), and PFNA (β=-0.4233, 95%CI: -0.6998, -0.1467). Furthermore, male participant ln(estradiol) levels were positively associated with PFOA (β=0.0921, 95%CI: 0.0186, 0.1656), and PFHxS (β=0.0462, 95%CI: 0.0020, 0.0905). Among females, a significant relationship was found only for PFDoA with ln(testosterone) (β=-0.0119, 95%CI: -0.0227, -0.0010). In conclusion, this study showed higher levels of PFASs coincide with lower testosterone and higher estradiol levels, and more significant associations of PFASs with reproductive hormone were found in males than in females.

Testosterone replacement therapy: who to evaluate, what to use, how to follow, and who is at risk?

BACKGROUND

Hypogonadism, defined as a low serum testosterone in the presence of signs and symptoms, is common, particularly in aging men. Testosterone supplementation therapy (TST) is the standard treatment for male hypogonadism. It has been demonstrated to have a significant impact on the signs and symptoms of hypogonadism, but there are concerns about the increase in TST and its potential adverse effects, particularly cardiovascular effects.

OBJECTIVE

This review presents health care providers with current information regarding the prevalence and impact of hypogonadism, as well as the diagnosis, evaluation, and treatment of hypogonadism. The beneficial and potential adverse effects are reviewed with a discussion on the current cardiovascular controversy.

METHODS

We reviewed current and "landmark" articles in the English-language literature pertaining to hypogonadism, its prevalence, etiologies, presentation, evaluation, and treatment.

RESULTS

Authorities in the field have offered guidelines and recommendations regarding the diagnosis, evaluation, and management of hypogonadism. Although there is a consensus as to the definition of hypogonadism as the presence of a low serum testosterone with signs and symptoms of hypogonadism, there is variability in the definition of "low testosterone." Various testosterone formulations exist, differing in route and frequency of administration as well as in side-effect profiles. Testosterone supplementation therapy should be continued in individuals demonstrating an improvement in signs and symptoms, which may take 3 months to a year for maximum response. Individuals treated with TST require monitoring for adverse effects. Further studies are needed to determine the impact of TST on cardiovascular health.

CONCLUSION

Hypogonadism is common, particularly in aging men. Symptomatic individuals who have no contraindications to TST should be offered treatment. A careful assessment of treatment response after adequate titration and duration of therapy as well as monitoring for adverse effects is essential in treating patients for hypogonadism. Although hypogonadism is associated with increased all-cause and cardiovascular-related mortality, controversy exists regarding the impact of TST on cardiovascular risk, highlighting the need for further studies.

Growth restriction alters adult spatial memory and sensorimotor gating in a sex-specific manner

In Western society, impaired uteroplacental blood flow is the major cause of human intrauterine growth restriction. Infants born small and who experience late childhood accelerated growth have an increased risk of developing adult diseases. Recent studies also suggest a link between birth weight and altered adult behavior, particularly relating to motor function, learning and memory, depression and schizophrenia. The aim of this study was to determine the relative influence of prenatal and postnatal growth restriction on adult behavioral outcomes in male and female rats. Uteroplacental insufficiency was induced in Wistar Kyoto rats by bilateral uterine vessel ligation on day 18 of gestation producing growth-restricted offspring (Restricted group). The Control group had sham surgery. Another group underwent sham surgery, with a reduction in litter size to five at birth equivalent to the Restricted litter size (Reduced Litter group). At 6 months of age, a series of behavioral tests were conducted in male and female offspring. Growth restriction did not impair motor function. In fact, Restricted and Reduced Litter males showed enhanced motor performance compared with Controls (P < 0.05). Spatial memory was greater in Restricted females only (P < 0.05). The Porsolts test was unremarkable, however, males exhibited more depressive-like behavior than females (P < 0.05). A reduction in sensorimotor gating function was identified in Reduced Litter males and females (P < 0.05). We have demonstrated that growth restriction and/or a poor lactational environment can affect adult rat behavior, particularly balance and coordination, memory and learning, and sensorimotor gating function, in a sex-specific manner.

An update on male hypogonadism therapy

INTRODUCTION

Men who have symptoms associated with persistently low serum total testosterone level should be assessed for testosterone replacement therapy.

AREAS COVERED

Acute and chronic illnesses are associated with low serum testosterone and these should be recognized and treated. Once the diagnosis of male hypogonadism is made, the benefits of testosterone treatment usually outweigh the risks. Without contraindications, the patient should be offered testosterone replacement therapy. The options of testosterone delivery systems (injections, transdermal patches/gels, buccal tablets, capsules and implants) have increased in the last decade. Testosterone improves symptoms and signs of hypogonadism such as sexual function and energy, increases bone density and lean mass and decreases visceral adiposity. In men who desire fertility and who have secondary hypogonadism, testosterone can be withdrawn and the patients can be placed on gonadotropins. New modified designer androgens and selective androgen receptor modulators have been in preclinical and clinical trials for some time. None of these have been assessed for the treatment of male hypogonadism.

EXPERT OPINION

Despite the lack of prospective long-term data from randomized, controlled clinical trials of testosterone treatment on prostate health and cardiovascular disease risk, the available evidence suggests that testosterone therapy should be offered to symptomatic hypogonadal men.

Symptoms of testosterone deficiency in early middle aged men

Symptoms of testosterone deficiency and concentrations of testosterone (T) and bioavailable testosterone (BT) were studied in 35- and 45-year-old men.

METHODS

A questionnaire, was sent to all 35- and 45-year-old men in Linköping, Sweden (n=1998). The questionnaire has earlier been used for 55- to 75-year-old men and included demographic data, medical history, different symptoms possibly of T deficiency and the 10 questions from the "ADAM-questionnaire". Totally 200 men randomly selected among the men who answered the questionnaire were asked to give blood samples for analysis of T- and BT-concentrations.

RESULTS

A total of 38.7% of the questionnaires were returned and analysed, and 43.5% of the 200 randomly selected men gave blood samples. The older age group reported more symptoms that may be connected to low B and BT and had lower T- and BT-concentrations. Less strong erections and higher alcohol consumption were associated with lower concentrations of BT in 45-year-old men.

CONCLUSIONS

The burden of symptoms possibly related to low T concentrations were higher in 45-year-old men, and BT and T were lower. However, due to the low answer frequency and number of blood samples analyzed no general conclusions can be drawn.

Hypogonadism in the aging male diagnosis, potential benefits, and risks of testosterone replacement therapy

Hypogonadism in older men is a syndrome characterized by low serum testosterone levels and clinical symptoms often seen in hypogonadal men of younger age. These symptoms include decreased libido, erectile dysfunction, decreased vitality, decreased muscle mass, increased adiposity, depressed mood, osteopenia, and osteoporosis. Hypogonadism is a common disorder in aging men with a significant percentage of men over 60 years of age having serum testosterone levels below the lower limits of young male adults. There are a variety of testosterone formulations available for treatment of hypogonadism. Data from many small studies indicate that testosterone therapy offers several potential benefits to older hypogonadal men. A large multicenter NIH supported double blind, placebo controlled study is ongoing, and this study should greatly enhance the information available on efficacy and side effects of treatment. While safety data is available across many age groups, there are still unresolved concerns associated with testosterone therapy. We have reviewed the diagnostic methods as well as benefits and risks of testosterone replacement therapy for hypogonadism in aging men.

Correlation between Frailty Level and Adverse Health-related Outcomes of Community-Dwelling Elderly, One Year Retrospective Study

Background

Frailty is considered to be a clinical syndrome characterized by decreased physiological reserves associated with a greater risk of health-related problems, hospitalization, and death. The current study examined hospitalization, falls, cognitive decline and disability between robust, prefrail and frail elderly in one year.

Methods

110 participants aged 65 or more who visited two senior welfare centers in Seoul from February 2008 to June 2008 were surveyed again from March 2009 to June 2009 with demographic characteristics, number of chronic diseases and medication, study of osteoporotic fractures (SOF) frailty index, instrumental activity of daily living (IADL), depression, mini-mental state examination-Korean version (MMSE-K), falling history and admission history within one year. These results were compared with participants' previous survey done one year ago.

Results

Among total 110 subjects, 48 (44%) robust, 30 (27%) prefrail, and 32 (29%) frail subjects changed to 26 (24%), 54 (49%), and 30 (27%) respectively over the year. There were statistical significances in age, number of chronic disease, depressive mood, MMSE, falls, hospitalization, IADL disability contributing to frailty (P < 0.05). Frailty defined by SOF frailty index was associated with greater risk of adverse outcomes. Frail subjects had a higher age-adjusted risk of cognitive function decline (odds ratio [OR], 3.57), disability (OR, 9.64), fall (OR, 5.42), and hospitalization (OR, 4.45; P < 0.005).

Conclusion

The frailty index like SOF frailty index might predict risk of falls, disability, hospitalization, and cognitive decline in the elderly, emphasizing special attention to the individuals showing frailty in outpatient examination.

More than half of the men in a Swedish population of men aged 55, 65 and 75 believe in 'a male climacteric'

AIM

Symptoms of late-onset hypogonadism (LOH) are often unspecific, and the existence of a male climacteric has been much debated. In this study, we investigate aging men's thoughts about, and beliefs, in a 'male climacteric'.

METHODS

A questionnaire was developed including background demographic data, symptoms possibly related to LOH and questions about men's thoughts and beliefs in a 'male climacteric'. All men, 55-, 65- and 75-years old, living in Linkoping, Sweden (n=1885) received the questionnaire.

RESULTS

One thousand three hundred fifty-six (72%) questionnaires were eligible for evaluation, 65.4% of the responders had heard of a 'male climacteric', and 42.2% believed it existed but only 3% had sought medical advice for these symptoms. More than half believed that a 'male climacteric' was related to decreased libido and less strong erections. Almost half of the men thought that decreased memory and/or dystymia and anxiousness were related to a male climacteric.

CONCLUSIONS

The majority of men have heard of a male climacteric, but only a minority had consulted a practitioner about their symptoms. More information and knowledge are needed, for the general population to better motivate men to seek medical advice and also for the health care professionals to better deal with the symptoms of LOH.

Frailty, serum androgens, and the CAG repeat polymorphism: results from the Massachusetts Male Aging Study

CONTEXT

The CAG repeat polymorphism in the androgen receptor, denoted (CAG)n, is thought to (inversely) index androgen sensitivity. We hypothesized that (CAG)n would exhibit a modifying influence on the association between circulating total and calculated free testosterone (TT and FT) and physical frailty in aging men.

OBJECTIVE

The objective of the study was to establish the influence of (CAG)n on the relation between circulating TT, FT, LH, SHBG, and frailty.

DESIGN

This was a prospective cohort study of health and endocrine functioning in randomly selected men, with a baseline (T1: 1987-89) and two follow-up (T2: 1995-1997; T3: 2002-2004) visits.

SETTING

This was an observational study of men residing in greater Boston, MA.

PARTICIPANTS

A total of 624 subjects aged 50-86 yr were retained.

MAIN OUTCOME MEASURES

The frailty phenotype was measured at T3. Components included weight loss, exhaustion, low physical activity, weakness, and slowness. Subjects exhibiting two of these five components were considered to be in an intermediate state, and those exhibiting three or more were considered frail.

RESULTS

(CAG)n was positively associated with TT and FT. Multivariable regression analyses revealed no influence of CAG on longitudinal within-subject changes in hormone levels or cross-sectional (T3) associations between hormone concentrations and the prevalence of intermediate frailty or frailty. Models incorporating subjects' history of hormone decline produced similar negative results.

CONCLUSIONS

This population-based study does not support the hypothesis that interindividual differences in (CAG)n can account for a lack of association between circulating androgens and the frailty phenotype. Longitudinal analyses are needed to confirm these conclusions.

Lower serum testosterone associated with elevated polychlorinated biphenyl concentrations in Native American men

BACKGROUND

Polychlorinated biphenyls (PCBs) and chlorinated pesticides are endocrine disruptors, altering both thyroid and estrogen hormonal systems. Less is known of action on androgenic systems.

OBJECTIVE

We studied the relationship between serum concentrations of testosterone in relation to levels of PCBs and three chlorinated pesticides in an adult Native American (Mohawk) population.

METHODS

We collected fasting serum samples from 703 adult Mohawks (257 men and 436 women) and analyzed samples for 101 PCB congeners, hexachlorobenzene (HCB), dichlorodiphenyldichloroethylene (DDE), and mirex, as well as testosterone, cholesterol, and triglycerides. The associations between testosterone and tertiles of serum organochlorine levels (both wet weight and lipid adjusted) were assessed using a logistic regression model while controlling for age, body mass index (BMI), and other analytes, with the lowest tertile being considered the referent. Males and females were considered separately.

RESULTS

Testosterone concentrations in males were inversely correlated with total PCB concentration, whether using wet-weight or lipid-adjusted values. The odds ratio (OR) of having a testosterone concentration above the median was 0.17 [95% confidence interval (CI), 0.05-0.69] for total wet-weight PCBs (highest vs. lowest tertile) after adjustment for age, BMI, total serum lipids, and three pesticides. The OR for lipid-adjusted total PCB concentration was 0.23 (95% CI, 0.06-0.78) after adjustment for other analytes. Testosterone levels were significantly and inversely related to concentrations of PCBs 74, 99, 153, and 206, but not PCBs 52, 105, 118, 138, 170, 180, 201, or 203. Testosterone concentrations in females are much lower than in males, and not significantly related to serum PCBs. HCB, DDE, and mirex were not associated with testosterone concentration in either men or women.

CONCLUSIONS

Elevation in serum PCB levels is associated with a lower concentration of serum testosterone in Native American men.

Testosterone and growth hormone improve body composition and muscle performance in older men

CONTEXT

Impairments in the pituitary-gonadal axis with aging are associated with loss of muscle mass and function and accumulation of upper body fat.

OBJECTIVES

We tested the hypothesis that physiological supplementation with testosterone and GH together improves body composition and muscle performance in older men.

DESIGN, SETTING, AND PARTICIPANTS

One hundred twenty-two community-dwelling men 70.8 +/- 4.2 yr of age with body mass index of 27.4 +/- 3.4 kg/m2, testosterone of 550 ng/dl or less, and IGF-I in lower adult tertile (< or =167 ng/dl) were randomized to receive transdermal testosterone (5 or 10 g/d) during a Leydig cell clamp plus GH (0, 3, or 5 microg/kg . d) for 16 wk.

MAIN OUTCOME MEASURES

Body composition by dual-energy x-ray absorptiometry, muscle performance, and safety tests were conducted.

RESULTS

Total lean body mass increased (1.0 +/- 1.7 to 3.0 +/- 2.2 kg) as did appendicular lean tissue (0.4 +/- 1.4 to 1.5 +/- 1.3 kg), whereas total fat mass decreased by 0.4 +/- 0.9 to 2.3 +/- 1.7 kg as did trunk fat (0.5 +/- 0.9 to 1.5 +/- 1.0 kg) across the six treatment groups and by dose levels for each parameter (P < or = 0.0004 for linear trend). Composite maximum voluntary strength of upper and lower body muscles increased by 14 +/- 34 to 35 +/- 31% (P < 0.003 in the three highest dose groups) that correlated with changes in appendicular lean mass. Aerobic endurance increased in all six groups (average 96 +/- 137 sec longer). Systolic and diastolic blood pressure increased similarly in each group with mean increases of 12 +/- 14 and 8 +/- 8 mm Hg, respectively. Other predictable adverse events were modest and reversible.

CONCLUSIONS

Supplemental testosterone produced significant gains in total and appendicular lean mass, muscle strength, and aerobic endurance with significant reductions in whole-body and trunk fat. Outcomes appeared to be further enhanced with GH supplementation.

Testosterone correlated to symptoms of partial androgen deficiency in aging men (PADAM) in an elderly Swedish population

OBJECTIVE

To investigate the prevalence of different symptoms of partial androgen deficiency in aging men (PADAM) and to correlate them with blood concentrations of testosterone and bioavailable testosterone.

DESIGN

A total of 370 men, aged 55 to 75 years, were invited to one of three primary healthcare centers in Sweden. They were asked to complete a questionnaire regarding demographic data, medical history, mood status, medication, castration therapy and smoking, exercise and alcohol habits, as well as different symptoms of PADAM. The 10 questions from a previously used questionnaire (the ADAM questionnaire) were included. The men were offered blood tests for analyses of testosterone, follicle stimulating hormone, luteinizing hormone, steroid hormone-binding globulin, and albumin. From these test results, we calculated the bioavailable testosterone.

RESULTS

Of the questionnaires sent out, 81.6% were returned and eligible for evaluation. Blood samples were obtained from 85.8% of men answering the questionnaire. Many of the symptoms, including five from the ADAM questionnaire, were more common in older age groups (P < 0.05). Three symptoms, deterioration in work performance, decreased strength and/or endurance, and bothersome hot flushes, were associated with low bioavailable testosterone and/or testosterone (P < 0.05). Testosterone and bioavailable testosterone did not differ between age groups, but bioavailable testosterone was higher in men with three or fewer symptoms on the ADAM questionnaire.

CONCLUSIONS

Symptoms associated with PADAM often occur in an elderly population, but we could only find an association between three symptoms and blood testosterone concentrations, one being bothersome hot flushes. It is likely that these symptoms have a more complex background than only PADAM.

Reliability and validation of a Chinese version of the Aging Males' Symptoms scale

This study was to assess whether the Chinese version of the Aging Males' Symptoms scale could measure aging men's symptoms as effectively as the English version. 176 psychiatric outpatient men were assessed to analyze internal consistency reliability and construct validity, and 45 male school staff were interviewed in estimating retest reliability. Cronbach alpha was .90, and the 3-wk. retest reliability was .72. Factor analysis yielded a two-factor structure. Construct validity was indicated by significant correlation between the two factors and the criterion variables. This scale is a validated and sensitive test for measuring symptoms in aging men in the Taiwanese Chinese-speaking population. It is suggested that the scale could be used to measure and compare health-related quality of life in groups of men over 40 years old.

Frailty and risk of falls, fracture, and mortality in older women: the study of osteoporotic fractures

BACKGROUND

A standard phenotype of frailty was associated with an increased risk of adverse outcomes including mortality in a recent study of older adults. However, the predictive validity of this phenotype for fracture outcomes and across risk subgroups is uncertain.

METHODS

To determine whether a standard frailty phenotype was independently associated with risk of adverse health outcomes in older women and to evaluate the consistency of associations across risk subgroups defined by age and body mass index (BMI), we ascertained frailty status in a cohort of 6724 women>or=69 years and followed them prospectively for incident falls, fractures, and mortality. Frailty was defined by the presence of three or more of the following criteria: unintentional weight loss, weakness, self-reported poor energy, slow walking speed, and low physical activity. Incident recurrent falls were defined as at least two falls during the subsequent year. Incident fractures (confirmed with x-ray reports), including hip fractures, and deaths were ascertained during an average of 9 years of follow-up.

RESULTS

After controlling for multiple confounders such as age, health status, medical conditions, functional status, depressive symptoms, cognitive function, and bone mineral density, frail women were subsequently at increased risk of recurrent falls (multivariate odds ratio=1.38, 95% confidence interval [CI], 1.02-1.88), hip fracture (multivariate hazards ratio [MHR]=1.40, 95% CI, 1.03-1.90), any nonspine fracture (MHR=1.25, 95% CI, 1.05-1.49), and death (MHR=1.82, 95% CI, 1.56-2.13). The associations between frailty and these outcomes persisted among women>or=80 years. In addition, associations between frailty and an increased risk of falls, fracture, and mortality were consistently observed across categories of BMI, including BMI>or=30 kg/m2.

CONCLUSION

Frailty is an independent predictor of adverse health outcomes in older women, including very elderly women and older obese women.

Chronic kidney disease (CKD) in the elderly -- a geriatrician's perspective

Chronic kidney disease (CKD) is becoming increasingly prevalent among many different populations all over the world, including the US and Europe. Its multitude of complications with devastating outcomes leads to a significantly higher risk for cardio-vascular and all-cause mortality in an individual. However, it is clear now that early detection of CKD might not only delay some of the complications but also prevent them. Therefore, various important public health organizations all over the world have turned their focus and attention to CKD and its risk factors, early detection and early intervention. Nevertheless, the general goals in preventing the increase in CKD and its complications are far from being completely achieved. Why is this so? What is the magnitude and complexity of the problem? How is it affecting the population - are there differences in its affection by age, gender or frail elderly versus the robust? Are we modifying the risk factors appropriately and aggressively? Are there subtle differences in managing the risk factors in those on dialysis versus the non-dialysis CKD patients? Is it important to treat anaemia of CKD aggressively, will it make a difference in the disease progression, its complications or to quality of life? What do these unfortunate individuals commonly succumb to? What do we advise patients who refuse dialysis or those who desire dialysis or transplant? Are there useful non-dialytic treatment recommendations for those who refuse dialysis? What is the role of the physicians caring for the elderly with CKD? When should the primary care givers refer a CKD patient to a nephrologist? The key to eventually controlling incident and prevalent CKD and improve quality of life of affected individuals, lies in not only knowing these and many other vital aspects, but also in applying such knowledge compulsively in day-to-day practice by each and every one us. As CKD is increasingly a disease of the elderly with men being affected more, this review details fairly comprehensively the vital aspects of CKD, especially from a primary care geriatrician's practical standpoint.

Testosterone therapy in the aging male

The decline, with aging, in serum concentrations of biologically active forms of testosterone in men is an indisputable fact and some men will eventually develop symptoms of late-onset hypogonadism (LOH) with its clinical consequences. LOH reduces quality of life and may pose important risk factors for frailty, changes in body composition, cardiovascular disease, sexual dysfunction and osteoporosis. Testosterone supplementation in cases of LOH will restore serum testosterone levels into the physiologic range; will restore metabolic parameters to the eugonadal state, increase muscle mass, strength, and function; maintaine or improve BMD reducing fracture risk; will improve neuropsychological function (cognition and mood); libido and sexual functioning; and enhance quality of life. The ultimate goals, however, are to maintain or regain a high quality of life, to reduce disability, to compress major illnesses into a narrow age range and to add life to years. To achieve these goals men must also adjust their lifestyle to optimize dietary habits, as well as to exercise and to abstain from smoking life-long. Monitoring these patients is a shared responsibility that cannot be taken lightly. The physician must emphasize to the patient the need for periodic evaluations and the patient must agree to comply with these requirements. The physician's evaluation should include an assessment of the clinical response and monitoring must be tailored to the indications and individual needs of the patient.

Age-Related Structural and Metabolic Changes in the Pelvic Reproductive End Organs

In this work, we provide preliminary data and a review of the literature regarding normal structural and functional changes that occur in the aging uterus, ovary, testicle, and prostate gland. It is expected that such knowledge will help physicians to distinguish physiologic changes from pathologic changes at an early stage. We retrospectively reviewed pelvic magnetic resonance imaging (MRI) scans of 131 female and 79 male subjects ages 13 to 86 years to determine changes in volume of the uterus, ovary, and prostate gland with age. Scrotal ultrasound examinations of 150 male subjects ages 0 to 96 years also were analyzed retrospectively to determine changes in testicular volume with age. In addition, (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) scans of 145 male subjects ages 11 to 90 years were analyzed retrospectively to assess for changes in maximum standardized uptake value (SUV(max)) of the testicles with age. The uterus had a mean volume of 38.55 +/- 3.68 cm(3) at 17 to 19 years of age, increased to a peak volume of 71.76 +/- 19.81 cm(3) between 35 to 40 years, and then declined to 24.02 +/- 8.11 cm(3) by the eighth decade of life. The maximal ovarian volume per subject maintained a relatively stable size in early life, measuring 9.46 +/- 3.25 cm(3) during the second decade of life, 8.46 +/- 3.32 cm(3) in the mid-fourth decade of life, and 7.46 +/- 3.33 cm(3) at 45 years of age, after which it declined to 4.44 +/- 2.02 cm(3) by the late fifth decade of life. The ovaries were not identifiable on MRI in subjects beyond the sixth decade of life. The volume of the prostate increased from 23.45 +/- 6.20 cm(3) during the second decade of life to 47.5 +/- 41.59 cm(3) by the late eighth decade of life; the central gland of the prostate increased from 9.96 +/- 3.99 cm(3) to 29.49 +/- 28.88 cm(3) during the same age range. Mean testicular volume was 11.2 +/- 5.9 cm(3). Testicular volume increased with age from birth to 25 years. After age 25, there was a significant decline in the testicular volume. The mean SUV(max) for the testicles was 1.9 +/- 0.5. Testicular metabolic activity demonstrated an increasing trend until the age of 35 years. A plateau in SUV(max) was observed after the age of 35 years until the age of 65 years. A slight decrease in SUV(max) was observed after the age of 65 years. The pelvic structures of men and women change both structurally and functionally over the lifespan, and such changes can be quantified using ultrasound, MRI, and (18)F-FDG-PET.

Testosterone, Sex Hormone–Binding Globulin, and Frailty in Older Men

OBJECTIVES

To determine whether testosterone (T) levels are associated with frailty or its components.

DESIGN

Population-based cohort study conducted in three waves (T1: 1987-1989, T2: 1995-1997, T3: 2002-2004).

SETTING

Communities in the Boston, Massachusetts, area.

PARTICIPANTS

Six hundred forty-six men aged 50 to 86 at T(3) with complete data on frailty components and hormone measurements.

MEASUREMENTS

The frailty phenotype was defined as the presence of three or more of the following: weight loss, exhaustion, low physical activity, slowness, and weakness. Men were classified as frail (> or = 3 components), intermediate (1-2 components), and nonfrail (0 components). Whether total and free T or sex hormone-binding globulin (SHBG) levels were associated cross-sectionally with frailty and with degree of frailty was determined. Potential confounders such as age, chronic disease, lifestyle factors, diet, and physical activity were considered.

RESULTS

No association was observed between total or free T and the frailty phenotype after adjusting for confounders. Conversely, a significant association was observed between SHBG and frailty phenotype with an adjusted odds ratio of 1.25 (95% confidence interval=1.06-1.46) per 10-nM increase in SHBG levels. Associations between hormones and degree of frailty were similar to those for overall frailty. Of frailty components, grip strength and physical activity, but not exhaustion, slow walking, or weight loss, were associated with total T levels, whereas SHBG was related to weight loss, exhaustion, and physical activity.

CONCLUSION

Total and free T levels were not associated with frailty phenotype, but SHBG was. Furthermore, T and SHBG levels were associated with some, but not all, components of frailty. Therefore, T trials in older men should focus on men experiencing decreases in strength.

Hormonal regulators of muscle and metabolism in aging (HORMA): design and conduct of a complex, double masked multicenter trial

BACKGROUND

Older persons often lose muscle mass, strength, and physical function. This report describes the challenges of conducting a complex clinical investigation assessing the effects of anabolic hormones on body composition, physical function, and metabolism during aging.

METHODS

HORMA is a multicenter, randomized double masked study of 65-90-year-old community dwelling men with testosterone levels of 150-550 ng/dL and IGF-1 < 167 ng/dL. Subjects were randomized to transdermal testosterone (5 or 10 g/day) and rhGH (0, 3, or 5 microg/kg/day) for 16 weeks. Outcome measures included body composition by DEXA, MRI, and (2)H(2)O dilution; muscle performance (strength, power, and fatigability), VO2peak, measures of physical function, synthesis/breakdown of myofibrillar proteins, other measures of metabolism, and quality of life.

RESULTS

Major challenges included delay in startup caused by need for 7 institutional contracts, creating a 142-page manual of operations, orientation and training, creating a 121-page CRF; enrollment inefficiencies; scheduling 16 evaluations/ subject; overnight admissions for invasive procedures and isotope infusions; large data and image management and transfer; quality control at multiples sites; staff turnover; and replacement of a clinical testing site. Impediments were largely solved by implementation of a web-based data entry and eligibility verification; electronic scheduling for multiple study visits; availability of research team members to educate and reassure subjects; more frequent site visits to validate all source documents and reliability of data entry; and intensifying quality control in testing and imaging. The study exceeded the target goal of 108 (n = 112) completely evaluable cases. Two interim DSMB meetings confirmed the lack of excessive adverse events, lack of center effects, comparability of subjects, and that distribution of subjects and enrollment will not jeopardize outcomes or generalizability of results.

CONCLUSIONS

Flexibility and rapidly solving evolving problems is critical when conducting highly complex multicenter metabolic studies.

Serum sex hormone and plasma homocysteine levels in middle-aged and elderly men

OBJECTIVE

To investigate whether circulating levels of testosterone (total, bioavailable), estradiol (total, bioavailable), and DHEA sulfate (DHEAS) are associated with fasting plasma homocysteine (tHcy) levels in middle-aged and elderly men.

DESIGN

A population-based sample of 400 independently living men between 40 and 80 years of age in a cross-sectional study.

METHODS

Total testosterone, sex hormone binding globulin (SHBG), and total estradiol were measured by RIA methods and bioavailable testosterone and estradiol were calculated. DHEAS was measured using an immunometric technique. Fasting homocysteine was measured by fluorescence polarization immunoassay. Anthropometric characteristics were also measured and two standardized questionnaires completed, including life-style factors and diet. Linear regression analysis adjusted for age, body mass index (BMI), creatinine clearance, and mean visceral fat was used to assess the association of endogenous sex hormones and fasting plasma homocysteine levels.

RESULTS

After adjustment for age, BMI, creatinine clearance, and mean visceral fat no statistically significant association was observed between testosterone (total, bioavailable), DHEAS, and estradiol (total, bioavailable)levels with natural log tHcy (beta = -2 x 10(-3); 95% confidence intervals (CI) -9 x 10(-3); 5 x 10(-3)), (beta = -4 x 10(-3); 95% CI -18 x 10(-3); 9 x 10(-3)), (beta = 3 x 10(-3); 95% CI -6 x 10(-3); 12 x 10(-3)), (beta = -9.3 x 10(-5); 95% CI -1 x 10(-3); 1 x 10(-3)), and (beta = 0.00; 95% CI -3 x 10(-3); 2 x 10(-3)) respectively. Additional adjustment for smoking, alcohol intake, daily physical activity, diabetes mellitus, and hypertension did not change these findings.

CONCLUSION

The results of our study do not support a direct role for circulating sex hormone levels in the regulation of fasting plasma tHcy concentrations in middle-aged and elderly men.

Prevalence of symptoms possibly related to PADAM, in a Swedish population aged 55, 65 and 75 years

OBJECTIVES

With age there is an average decline in the concentration of biologically active testosterone. It is still controversial if this leads to a clinically relevant deficit, "partial androgen deficiency of the ageing man" (PADAM). Our objective was to investigate the prevalence of a series of symptoms possibly associated with PADAM in an assumed normal-population of older men.

METHODS

We developed a questionnaire including items about symptoms possibly associated with PADAM as well as background data covering demography, medical history, mood status, medication, castration therapy, as well as smoking, exercise and alcohol habits. The 10 items of the ADAM-questionnaire, designed to predict low bio-available T, were also included. The questionnaire was sent to all 1885 men 55, 65 or 75-years-old, living in Linköping, Sweden.

RESULTS

We identified a number of symptoms that differed significantly (P < 0.01) between age groups, e.g., "increased abdominal circumference", "decrease in muscle strength and/or endurance", "decreased libido", "less strong erection" and "lack of energy". From factorial analysis we found that the symptoms co-varied in four different groups.

CONCLUSION

The prevalence of a number of symptoms differed significantly between age groups, but we cannot infer that there is a causal connection between an average age-dependent decline in testosterone function and these symptoms. There are several other ways to interpret these results like the existence of concurrent somatic and/or mood disorders or ageing as such. For this purpose further studies including measurements of testosterone concentrations relating to the findings of this study have to be performed.

Heritability of plasma sex hormones and hormone binding globulin in adult male twins

Plasma sex hormone concentrations have been used as biomarkers in epidemiological studies of many conditions including cancer, obesity, bone density, and coronary heart disease. The objective of this analysis was to estimate genetic and nongenetic influences on endogenous sex hormones (testosterone, estradiol, estrone, and SHBG) in a large sample of 532 adult white male twins (134 monozygotic and 132 dizygotic twin pairs) from the National Heart, Lung, and Blood Institute Twin Study. Participants were aged 59-70 yr at the time of plasma collection, and hormone concentrations were determined with RIA. Genetic models were fitted by the method of maximum likelihood. Testosterone and SHBG concentrations have substantial genetic variation, with additive genetic factors accounting for 57 and 68% of the total phenotypic variation, respectively. In contrast, variation in estrone (37% shared environmental and 63% individual specific environmental effects) and estradiol concentrations (25% genetic effect, 44% shared environmental effects, and 31% individual specific environmental effects) were largely influenced by nongenetic factors. Assessment of the relative contribution of genetic and nongenetic influences on hormone concentrations may help in the search for genes underlying variation and covariation in complex traits affected by plasma sex hormone concentrations.

Timing and choice of androgen ablation

Hormone therapy remains central to the management of advanced prostate cancer. Evidence has accrued to suggest benefits from earlier treatment. Trials which demonstrate significant improvements in disease-specific survival may be underpowered to show overall survival benefits, due to the effect of mortality from unrelated causes. Toxicity, particularly the risk of osteoporosis, causes increasing concern, particularly where many years of use may be contemplated as in early relapse after curative treatment. Strategies to reduce toxicity include use different drugs, notably antiandrogens and with renewed interest in oestrogens in low dose or administered parenterally, and deferred and intermittent treatment. Further improvements in drug development, reducing toxicity, and identification of the cause of hormone refractory disease and its prevention would revolutionise the use of hormone therapy. Currently, deferred treatment, used selectively and with careful follow-up, remains an option for selected patients.

Low testosterone is associated with decreased function and increased mortality risk: a preliminary study of men in a geriatric rehabilitation unit

OBJECTIVES

To evaluate whether low testosterone levels are associated with greater depression or poorer function in a geriatric rehabilitation unit.

DESIGN

Retrospective review.

SETTING

Geriatric rehabilitation unit.

MEASUREMENTS

Low testosterone levels were defined as total testosterone of 3.0 ng/mL or less or free testosterone of 9.0 pg/mL or less. Age, ethnicity, weight, depression, ambulation, length of rehabilitation, and 6-month rehospitalization and mortality rates were obtained. Overall illness severity was determined using the Cumulative Illness Rating Scale for Geriatrics.

RESULTS

Low testosterone levels were present in 29 of 44 (65.9%) men. There were no significant differences between men with low and normal testosterone levels in ethnicity, age, weight, depression, and overall illness severity. Lower testosterone levels were correlated with decreased ability to ambulate and transfer (Spearman P>.34; P<.05). There were no significant differences between men with low and normal testosterone in length of stay on the rehabilitation unit (mean+/-standard deviation= 19.6+/-11.6 vs 17.7+/-17.5 days, P=.68) or rehospitalization rates (41.4% vs 26.7%; P=.34). Men with low testosterone had a trend toward increased 6-month mortality (31.0% vs 6.7%; chi(2)=3.3, P=.07) and shorter survival time (log rank=3.2; df 1, P=.07). After entering testosterone and variables with potential prognostic significance for mortality in a stepwise manner in a Cox regression analysis, there was a significant mortality risk associated with low testosterone (hazard ratio=27.9, 95% confidence interval=2.0-384.0; P=.01).

CONCLUSION

Low testosterone levels were correlated with decreased physical function and increased risk for 6-month mortality. Prospective studies with larger sample sizes and better standardized testosterone measures are needed to confirm these findings.

Male Osteoporosis

Osteoporosis is a common condition in men affecting approximately 2 million males in the US. Compared with women, osteoporosis develops later in life and the incidence of osteoporosis-related fractures is lower in men. The morbidity and mortality associated with osteoporotic fractures are much greater in men compared with women, and secondary causes of osteoporosis are more frequently (in approximately 50% of cases) identified in men compared with women with osteoporosis. Excessive alcohol consumption, glucocorticoid excess and hypogonadism are the most commonly identified causes. Primary osteoporosis in men has been linked to changes in sex steroid secretion, the growth hormone-insulin-like growth factor-1 (GH-IGF-1) axis and the vitamin D-parathyroid hormone (PTH) 25-hydroxyvitamin D [25(OH)D]-PTH system. Diagnosing osteoporosis in men is complicated by an ongoing debate on whether to use sex-specific reference values for bone mineral density (BMD) or female reference values. The International Society for Clinical Densitometry recommended using a T score of -2.5 or less of male reference values to diagnose osteoporosis in men who are > or =65 years of age. However, this definition is yet to be validated in terms of fracture incidence and prevalence. Ensuring adequate calcium and vitamin D intake is the cornerstone of any regimen aimed at preventing or treating osteoporosis in men. Bisphosphonates are currently the therapy of choice for treatment of male osteoporosis. A short course of parathyroid hormone (1-34) [teriparatide] may be indicated for men with very low BMD or in those in whom bisphosphonate therapy is unsuccessful. The use of testosterone-replacement therapy for the prevention and treatment of male osteoporosis remains controversial but likely to benefit osteoporotic men with evident hypogonadism.

5alpha-reduced androgens may have actions in the hippocampus to enhance cognitive performance of male rats

Androgens may improve cognitive performance; however, these effects and mechanisms of androgens are not well understood. Whether testosterone's (T) effects on cognitive performance are mediated by its 5alpha-reduced, non-aromatizable metabolite dihydrotestosterone (DHT) and/or its 3alpha-hydroxysteroid dehydrogenase (3alpha-HSD) reduced metabolite 3alpha-androstanediol (3alpha-diol), was investigated. In Experiment 1, male rats that were gonadally intact, or gonadectomized (GDX) and DHT-replaced with a silastic capsule, had better performance in the inhibitory avoidance task, and higher plasma DHT and 3alpha-diol levels, compared to GDX rats. In Experiments 2-4, intra-hippocampal indomethacin, a 3alpha-HSD inhibitor, to intact or DHT-replaced, but not GDX, rats decreased performance in the inhibitory avoidance task and reduced hippocampal 3alpha-diol levels compared to that observed in rats with control implants. Thus, the 5alpha-reduced androgen DHT has cognitive-enhancing effects, independent of E(2), which are attenuated by a 3alpha-HSD inhibitor, indomethacin. These results suggest that 5alpha-reduced androgens may have actions in the hippocampus to improve cognitive performance.

Aging, Physical Activity, and Hormones in Women—A Review

Women experience significant changes in endocrine function during aging. Decreasing levels of anabolic hormones may be associated with musculoskeletal atrophy and decrease in function that is observed in older women and, as a result, there has been an increase in the use of pharmacological hormone therapies. It is difficult to distinguish, however, between physiological changes that are truly age related and those that are associated with lifestyle factors such as physical activity participation. Some research has shown that circulating levels of anabolic hormones such as DHEA(S) and IGF-I in older women are related to physical activity, muscle function, and aerobic power. Exercise-intervention studies have generally shown that increasing age blunts the acute hormonal response to exercise, although this might be explained by a lower exercise intensity in older women. There have been relatively few studies that examine hormonal adaptations to exercise training. Physical activity might have an effect on hormone action as a result of changes in protein carriers and receptors, and future research needs to clarify the effect of age and exercise on these other components of the endocrine system. The value and safety of hormone supplements must be examined, especially when used in combination with an exercise program.

Andropause and psychopathology: minor symptoms rather than pathological ones

This study examined the psychological symptomatology of men diagnosed with andropause and the association between calculated free testosterone (T) and depressed mood, anxiety and quality of life. Subjects were 153 men, aged 50-70 years, who participated in a screening of andropause. Total testosterone, FSH, LH and SHBG levels were measured. Depressed mood was assessed with the Carroll Rating Scale, anxiety with the "anxiety-insomnia" dimension of the General Health Questionnaire, and quality of life with the World Health Organisation Quality of Life questionnaire. The results showed that levels of free T decreased with age, whereas FSH and LH increased. Carroll Rating Scale scores were higher among hypogonadal subjects, but the mean score was low and not pathological. A negative correlation was observed between severity of depression as assessed by the Carroll Rating Scale and free T levels. However, subjects with a significant score on this scale did not exhibit different free T levels compared to subjects with a non-significant depressive score. Anxiety and quality of life did not differ between hypogonadal and eugonadal subjects. The present study therefore suggests that andropause is not characterised by specific psychological symptoms, but may be associated with "depressive symptoms" that are not considered as pathological.

Radiation therapy induced changes in male sex hormone levels in rectal cancer patients

BACKGROUND AND PURPOSE

To determine the effect of curative radiation therapy (46-50 Gy) on the sex hormone levels in male rectal cancer patients.

MATERIALS AND METHODS

Twenty-five male rectal cancer patients (mean age 65 years), receiving pelvic radiation therapy (2 Gyx23-25 fractions in 5 weeks) were included. Serum testosterone, FSH and LH were determined before start of treatment, at the 10th and 25th fractions, and 4-6 weeks after completed radiotherapy. The testicular dose was determined by thermoluminescent dosimetry.

RESULTS

Five weeks of radiation therapy (46-50 Gy) resulted in a 100% increase in serum FSH, a 70% increase in LH, and a 25% reduction in testosterone levels. After treatment, 35% of the patients had serum testosterone levels below lower limit of reference. The mean radiation dose to the testicles was 8.4 Gy. A reduction in testosterone values was observed already after a mean dose of 3.3 Gy (10th fraction).

CONCLUSION

Radiation therapy (46-50 Gy) for rectal cancer resulted in a significant increase in serum FSH and LH and a significant decrease in testosterone levels, indicating that sex hormone production is sensitive to radiation exposure in patients with a mean age of 65 years.

The ageing male and erectile dysfunction

Erectile dysfunction is common in the ageing man and reliable therapies are needed. The pathophysiology of erectile dysfunction in this group mainly includes chronic ischaemia, which triggers the deterioration of cavernosal smooth muscle and the development of corporeal fibrosis. Assessing the ageing man with erectile dysfunction who seeks medical treatment should comprise a thorough medical and sexual history, a systemic and focused physical examination and selected blood tests. Oral drug therapy represents a safe and effective option for most ageing men.

Testosterone, but not nonaromatizable dihydrotestosterone, improves working memory and alters nerve growth factor levels in aged male rats

Recent studies have suggested that testosterone levels are lower in men with Alzheimer's disease and that testosterone treatment improves cognition in older men. Since testosterone can be aromatized to estrogen, testosterone's effects could be due to conversion into estrogen. We treated aged male rats with either testosterone or dihydrotestosterone (DHT), the latter of which is not aromatized to estrogen, in order to determine whether these treatments improve spatial working and reference memory as assessed in the water radial arm maze. We also tested whether such effects are related to beta-amyloid levels in the hippocampus or neurotrophin levels in the hippocampus, entorhinal cortex, frontal cortex, or striatum. Aged rats made more errors than young rats on all memory measures. Testosterone, but not DHT, improved working memory and decreased hippocampal NGF protein in aged rats, while having no effect on beta-amyloid. However, higher beta-amyloid levels were correlated with poorer working memory performance in young rats. Neurotrophin levels in entorhinal cortex were positively correlated with errors for all memory measures in androgen-treated rats. Similar to findings in human studies, in our study androgen treatment lowered circulating estradiol levels in aged rats, suggesting that androgen treatment exerts feedback to the hypothalamic pituitary axis and that conversion to estrogen may not be the underlying biological mechanism of testosterone's effects on memory and growth factor levels. The ratio of estradiol to testosterone, or the actions of the aromatase enzyme itself, may be responsible for the observed effects. These data support the hypothesis that testosterone therapy in aging men may provide positive effects on cognition and that neural regions that are linked to cognition, such as the hippocampus and/or entorhinal cortex, may be involved in such effects.