Serum total and free testosterone level of Japanese men: a population-based study

Association between Fish Intake and Serum Testosterone Levels in Older Males: The Hitachi Health Study II

Background

Fish are rich in omega-3 polyunsaturated fatty acids and vitamin D, which can promote testosterone synthesis and secretion. However, some contaminants present in fish may disrupt testosterone production.

Objective

This study aimed to investigate the association between fish intake (total, fatty, and lean fish) and serum testosterone levels in older males.

Methods

This cross-sectional study included 1545 Japanese males aged 60-69 y who participated in the baseline survey of the Hitachi Health Study II. Fish intake was estimated using a validated brief-type self-administered diet history questionnaire. Total testosterone levels were measured by chemiluminescence immunoassay. Multivariable linear regression analysis was used to analyze the association between fish intake and serum testosterone levels.

Results

Higher total fish intake was associated with higher levels of serum testosterone, with an adjusted mean [95% confidence interval (CI) of 5.63 (5.43, 5.83) and 5.99 (5.78, 6.20)] ng/mL for the 1st and 4th quartiles of total fish intake, respectively (P for trend = 0.06). When analyzing fatty and lean fish separately, higher intake of lean fish, but not fatty fish, was associated with higher levels of serum testosterone: adjusted mean (95% CI): 5.63 (5.43, 5.82) and 6.00 (5.79, 6.20) ng/mL for the 1st and 4th quartiles of lean fish intake, respectively (P for trend = 0.01).

Conclusions

Among older males, higher intake of total fish, particularly lean fish, was associated with higher serum testosterone levels. Curr Dev Nutr 20xx;x:xx.

Clinical efficiency of combination therapy using testosterone replacement therapy, phosphodiesterase 5 inhibitors and Kampo herbal medicine for eugonadal patients with late-onset hypogonadism syndrome

In the present study, the initial treatment efficiency of combination therapy using testosterone replacement therapy (TRT), herbal medicine and phosphodiesterase 5 inhibitors (PDE5i) in male patients with late-onset hypogonadism (LOH) were assessed. A total of 21 patients were enrolled and after 12 weeks, the clinical efficacy was evaluated based on improvement of LOH symptoms via laboratory parameters and several questionnaires, including the Ageing Males' Symptoms (AMS) scale. The overall AMS scores, as well as the psychological, physical and sexual AMS factors prior to and after treatment in the TRT, testosterone enanthate (T enanthate) monotherapy and T enanthate + PDE5i treatment groups were significantly improved. In the herbal medicine group, only the AMS physiological factors were significantly improved after treatment compared with the baseline. The improvement of the overall AMS scores, as well as the physiological and sexual AMS factors, were significantly negatively correlated with the free testosterone (FT) value prior to treatment. In conclusion, treatment with combination therapy using TRT, herbal medicine and PDE5i improved AMS scores in patients with LOH syndrome. Particularly in patients with LOH syndrome and low FT, the symptoms were significantly improved following combination therapy.

Androgen Misuse and Abuse

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

Cysteine Sulfoxides Enhance Steroid Hormone Production via Activation of the Protein Kinase A Pathway in Testis-Derived I-10 Tumor Cells

Testosterone plays an important role in male sexual characteristics and maturation, and decreased testosterone levels increase the risk of several diseases. Recently, onion extract rich in cysteine sulfoxides, which are amino acids unique to onions, has been reported to alleviate age-related symptoms resulting from decreased testosterone levels in males. However, the mechanism underlying the suppression of low testosterone levels by cysteine sulfoxides has not been elucidated. In this study, we found that onion extract containing cysteine sulfoxides enhanced progesterone, a precursor of testosterone, in mouse testis-derived I-10 tumor cells. Furthermore, cysteine sulfoxides activated protein kinase A (PKA) and cyclic adenosine monophosphate response element-binding protein, which are key factors in steroidogenesis. These results suggest that cysteine sulfoxides enhance steroid hormone production via activation of the PKA signaling pathway.

Erectile Dysfunction in Germ Cell Tumor Survivors

Purpose

Germ cell tumors (GCTs) are the most common malignant neoplasms in adolescents and young adults, and most patients with these tumors can be completely cured. Therefore, maintaining quality of life (QOL) is important. Erectile dysfunction (ED) is one factor that reduces the QOL of GCT survivors. We aimed to clarify the relationship between ED and age, follow-up period, serum levels of hormones, and treatment methods for GCT survivors.

Materials and Methods

We evaluated ED using the Sexual Health Inventory for Men questionnaire (SHIM) and measured serum levels of hormones in survivors after GCT treatment. The relationships between the SHIM score responses and age, serum levels of hormones, follow-up period, and treatment methods were assessed using a logistic analysis.

Results

Fifty-two GCT survivors were enrolled and 46 survivors completed the SHIM. The median age, follow-up period, and SHIM score were 38 years, 35 months, and 18, respectively. Regarding the SHIM scores, 85% had scores <22 and 46% had scores <17. The percentage of SHIM scores <17 was 69% in patients with under 2 years of follow-up. It significantly improved to 33% in patients with over 2 years of follow-up. The multivariate analysis identified the follow-up period as an independent factor for SHIM scores <17. Age, serum levels of hormone, and treatment method were not significant factors for SHIM scores <17.

Conclusions

Improvement of SHIM score can be expected after GCT treatment regardless of age, serum levels of hormone, and treatment method.

Deterioration of sexual function is associated with central hemodynamics in adult Japanese men

Elevated aortic blood pressure is more strongly related to the onset of cardiovascular disease (CVD) than elevated brachial blood pressure. On the other hand, erectile dysfunction (ED) is a peripheral vascular disfunction and is also associated with CVD; however, the association between aortic blood pressure and ED has not yet been clarified. Therefore, we aimed to investigate the association between ED severity and aortic blood pressure in adult men. In 253 Japanese adult men (59 ± 16 years), aortic (estimated using a generalized transfer function) and peripheral hemodynamics were measured. Erectile function was assessed with a questionnaire (the International Index of Erectile Function 5: IIEF5), and participants were stratified into three groups based on the IIEF5 score (no ED, mild-to-moderate ED, and moderate-to-severe ED). Aortic systolic blood pressure (SBP) and pulse pressure (PP) were significantly higher in subjects with moderate-to-severe ED than in subjects with no ED or mild-to-moderate ED. In addition, the severity of ED was significantly associated with the time to reflection, augmentation pressure, and augmentation index. Multivariate linear regression analyses suggested that moderate-to-severe ED was significantly associated with aortic SBP and PP (β = 0.129; p = 0.047, β = 0.165; p = 0.013, respectively) but not brachial SBP or PP, after confounding factors were considered. These results suggest that moderate-to-severe ED is associated with elevated aortic blood pressure due to an earlier arrival of the reflected wave and is an independent predictor of elevated aortic blood pressure in Japanese men.

Clinical relevance of low androgen to gastroesophageal reflux symptoms

The aim of this study was to determine the relationships between free testosterone (FT) level and parameters including laboratory data and data from questionnaires and to determine symptoms leading to the detection of late onset hypogonadism (LOH). We retrospectively reviewed medical records of patients in whom serum FT was measured in our hospital. Aging Male Symptoms (AMS) score, self-rating depression scale (SDS) and frequency scale for the symptoms of gastroesophageal reflux disease (FSSG) score were used for questionnaires. A total of 205 patients were included in the analysis (55.2 ± 15.6 years of age, mean ± SD). Among them, 119 patients (58.0%) had an FT level of less than 8.5 pg/mL, which fulfills the diagnostic criterion of LOH syndrome according to the clinical practice manual for LOH in Japan. It was revealed that FSSG score was inversely correlated to serum FT levels (r = -0.3395, p < 0.001), although SDS and AMS scales did not show significant correlations to FT levels. Our study revealed a high prevalence of LOH syndrome among patients in whom the majority complained of general symptoms. Although GERD symptoms are generally not considered to be typical symptoms of LOH, our study indicates that those symptoms might be clues for the detection of LOH.

High prevalence of hypogonadism determined by serum free testosterone level in Japanese testicular cancer survivors

OBJECTIVE

Hypogonadism is a major complication in testicular cancer survivors, but its prevalence varies among studies. In Japan, free testosterone has been used for diagnosis of late-onset hypogonadism syndrome. In the present study, we evaluated the hormone level of testicular cancer survivors and its impact on their quality of life.

METHODS

Overall, 50 testicular cancer survivors treated from 1990 to 2013 were enrolled. The median age was 44 years. The serum levels of free testosterone, total testosterone and luteinizing hormone were measured. All patients completed the Aging Males' Symptom scale and International Index of Erectile Function-15. The hormone levels of 337 healthy volunteers were used as the control.

RESULTS

A total of 32 (64%) patients showed free testosterone levels <8.5 pg/mL. In contrast, just 26% of 50 patients showed total testosterone levels <3.5 ng/mL. Testicular cancer survivors had significantly lower free testosterone and higher luteinizing hormone compared with healthy controls. In contrast, there was no difference in total testosterone between patients and controls. The prevalence of late-onset hypogonadism symptoms of any grade (Aging Males' Symptom total score ≥27) was 60%. Overall, 64% were defined as having moderate erectile dysfunction (International Index of Erectile Function-Erectile Function domain score <17). However, Aging Males' Symptom, International Index of Erectile Function-15 and Erectile Function domain scores did not differ by free testosterone or total testosterone level.

CONCLUSIONS

This is the first report on the prevalence of hypogonadism determined by free testosterone level in Japanese testicular cancer survivors. Because Aging Males' Symptom and International Index of Erectile Function-15 scores do not necessarily reflect the hormone level, measuring free testosterone is also important in the follow up of these patients.

An independent validation study of three single nucleotide polymorphisms at the sex hormone-binding globulin locus for testosterone levels identified by genome-wide association studies

Study question

Are the single nucleotide polymorphisms (SNPs) rs2075230, rs6259 and rs727428 at the sex hormone-binding globulin (SHBG) locus, which were identified by genome-wide association studies (GWASs) for testosterone levels, associated with testosterone levels in Japanese men?

Summary answer

The SNP rs2075230, but not rs6259 and rs727428, is significantly associated with testosterone levels in Japanese men.

What is already known

Previous GWASs have revealed that rs2075230 is associated with serum testosterone levels in 3495 Chinese men and rs6259 and rs727428 are associated with serum testosterone levels in 3225 men of European ancestry.

Study design, size, and duration

This is an independent validation study of 1687 Japanese men (901 in Cohort 1 and 786 in Cohort 2).

Participants/materials, setting and method

Cohort 1 (20.7 ± 1.7 years old, mean ± SD) and Cohort 2 (31.2 ± 4.8 years) included samples obtained from university students and partners of pregnant women, respectively. The three SNPs were genotyped using either TaqMan probes or restriction fragment length polymorphism PCR. Blood samples were drawn from the cubital vein of the study participants in the morning, and total testosterone and SHBG levels were measured using a time-resolved immunofluorometric assay. Association between each SNP and testosterone levels was evaluated by meta-analysis of the two Japanese male cohorts.

Main results and the role of chance

The age of the two cohorts was significantly different (P < 0.0001). We found that rs2075230 was significantly associated with serum testosterone levels (β_STD = 0.15, P = 7.2 × 10⁻⁶); however, rs6259 and rs727428 were not (β_STD = 0.17, P = 0.071; β_STD = 0.082, P = 0.017, respectively), after adjusting for multiple testing in a combined analysis of two Japanese male cohorts. Moreover, rs2075230, rs6259 and rs727428 were significantly associated with high SHBG levels (β_STD = 0.22, P = 3.4 × 10⁻¹²; β_STD = 0.23, P = 6.5 × 10⁻⁶ and β_STD = 0.21, P = 3.4 × 10⁻¹⁰, respectively).

Large scale data

Not applicable.

Limitations, reasons for caution

This study had differences in the age and background parameters of participants compared to those observed in previous GWASs. In addition, the average age of participants in the two cohorts in our study also differed from one another. Therefore, the average testosterone levels, which decrease with age, between studies or the two cohorts were different.

Wider implications of the findings

The three SNPs have a considerable effect on SHBG levels and hence may indirectly affect testosterone levels.

Study funding/competing interests

This study was supported partly by the Ministry of Health and Welfare of Japan (1013201) (to T.I.), Grant-in-Aids for Scientific Research (C) (26462461) (to Y.S.) and (23510242) (to A.Ta.) from the Japan Society for the Promotion of Science, the European Union (BMH4-CT96-0314) (to T.I.) and the Takeda Science Foundation (to A.Ta.). There are no conflicts of interest to declare.

Effects of long-term androgen replacement therapy on the physical and mental statuses of aging males with late-onset hypogonadism: a multicenter randomized controlled trial in Japan (EARTH Study)

Androgen replacement therapy (ART) efficacy on late-onset hypogonadism (LOH) has been widely investigated in Western countries; however, it remains controversial whether ART can improve health and prolong active lifestyles. We prospectively assessed long-term ART effects on the physical and mental statuses of aging men with LOH in Japan. The primary endpoint was health-related quality of life assessed by questionnaires. Secondary endpoints included glycemic control, lipid parameters, blood pressure, waist circumference, body composition, muscular strength, International Prostate Symptom Scores (IPSS), International Index of Erectile Function-5 (IIEF-5) scores, and serum prostate-specific antigen levels. Of the 1637 eligible volunteers, 334 patients > 40 years with LOH were randomly assigned to either the ART (n = 169) or control groups (n = 165). Fifty-two weeks after the initial treatment, ART significantly affected the role physical subdomain of the short form-36 health survey (SF-36) scale (P = 0.0318). ART was also associated with significant decreases in waist circumstance (P = 0.002) and serum triglyceride (TG) (P = 0.013) and with significant increases in whole-body and leg muscle mass volumes (P = 0.071 and 0.0108, respectively), serum hemoglobin (P < 0.001), IPSS voiding subscore (P = 0.0418), and the second question on IIEF-5 (P = 0.0049). There was no significant difference between the groups in terms of severe adverse events. In conclusion, in patients with LOH, long-term ART exerted beneficial effects on Role Physical subdomain of the SF-36 scale, serum TG, waist circumstance, muscle mass volume, voiding subscore of IPSS, and the second question of IIEF-5. We hope our study will contribute to the future development of this area.

Female sexual dysfunction in androgenetic alopecia: Case-control study

INTRODUCTION

We sought to evaluate the association of female sexual dysfunction (FSD) with androgenetic alopecia (AGA) and metabolic syndrome (MetS) in premenopausal women.

METHODS

From December 2013 to June 2015, we performed a case-control, prospective study of 115 patients with AGA and 97 age-matched control patients without AGA from among premenopausal women who visited dermatology clinics of the two reference hospitals. Comprehensive history, anthropometric measurements, and questionnaire administration were performed for each of the total of 212 women. The Female Sexual Function Index (FSFI) was used to assess the key dimensions of female sexual function. AGA was assessed and graded by an experienced dermatologist according to Ludwig's classification. The MetS assessment was made according to the NCEP-ATP III criteria.

RESULTS

In univariate analysis, age, weight, waist circumference, hip circumference, waist-to-hip ratio, body mass index (BMI), AGA, MetS, cardiovascular event, marital status, hypertension, high fasting plasma glucose, high triglyceride, large waist, total testosterone, and free testosterone were associated with presence of FSD. In logistic regression analysis, age (odds ratio [OR] 1.21, 95% confidence interval [CI] 1.13-1.30; p<0.001), AGA (OR 3.42, 95% CI 1.31-8.94; p=0.017), MetS (OR 5.39, 95% CI 1.34-21.62; p=0.012), and free testosterone (OR 0.18, 95% CI 0.09-0.37; p<0.001) were independently associated with FSD.

CONCLUSIONS

Our study suggests that age, AGA, MetS, and free testosterone may have strong impact on sexual function in premenopausal women. Further studies with population-based and longitudinal design should be conducted to confirm this finding.

Relationship between low free testosterone levels and loss of muscle mass

We assessed longitudinal relationships between baseline testosterone and muscle mass changes in Japanese men. Data were collected from community-dwelling 957 adult men who participated in a longitudinal study of ageing biennially from 1997–2010. Appendicular muscle mass (AMM) was measured with dual-energy X-ray absorptiometry at baseline and follow-up examinations. The cut-off point of sarcopenia was defined as a skeletal muscle index (AMM/height²) < 6.87 kg/m². Total testosterone (TT) and free testosterone (FT) were measured with a radioimmunoassay. The calculated FT (cFT) was determined with a formula using albumin, TT, and sex hormone-binding globulin levels. We analyzed 4,187 or 2,010 cumulative data points using generalized estimating equations. Low TT was not associated with sarcopenia. Low cFT (odds ratio = 2.14, 95% confidence interval: 1.06–4.33) and FT (odds ratio = 1.83, 95% confidence interval: 1.04–3.22) were associated with sarcopenia. Low FT may be a predictor of risk for muscle loss in Japanese men.

Comparison of testosterone fractions between Framingham Heart Study participants and Japanese participants

OBJECTIVES

To determine testosterone fractions in Japanese men and to compare these values with those of Framingham Heart Study participants.

METHODS

We enrolled 498 healthy Japanese men. Total testosterone was assayed by liquid chromatography tandem mass spectrometry, sex hormone-binding globulin was assayed by immunoassay and free testosterone was calculated by a laboratory at the Boston Medical Center. Analog-based free testosterone and immunoassay-based total testosterone were determined by immunoassay. We compared mass spectrometry assay-based total testosterone and calculated free testosterone values in the Japanese participants with values in the American Framingham Heart Study third generation cohort.

RESULTS

The mean serum mass spectrometry assay-based total testosterone, sex hormone-binding globulin, and calculated free testosterone values were 439.4 ± 167 ng/dL, 65.34 ± 30.61 nmol/L, and 58.75 ± 20.0 pg/mL, respectively. The correlation coefficients with age for mass spectrometry assay-based total testosterone, sex hormone-binding globulin, and calculated free testosterone were 0.0010, 0.5041, and -0.496, respectively. There were no age-related changes in mass spectrometry assay-based total testosterone values in healthy men (P = 0.981), whereas sex hormone-binding globulin and calculated free testosterone levels showed similar age-related changes (P < 0.0001). Serum analog-based free testosterone levels (8.24 ± 2.9 pg/mL) showed age-related changes (P < 0.0001) regardless of immunoassay-based total testosterone levels (P = 0.828). Serum immunoassay-based total testosterone values (486.1 ± 162.5 ng/dL) correlated with serum mass spectrometry assay-based total testosterone values (r = 0.740, 95% confidence interval 0.6965-0.7781, P < 0.0001). Similarly, analog-based free testosterone and calculated free testosterone values showed a highly significant correlation (r = 0.706, 95% confidence interval 0.6587-0.7473, P < 0.0001). The analog-based free testosterone values were approximately 10% of the calculated free testosterone values.

CONCLUSIONS

In contrast to the Framingham Heart Study cohort, total testosterone values in Japanese men are not associated with advancing age; thus, they cannot be used to diagnose late-onset hypogonadism in Japan. The analog-based free testosterone value can be considered instead as a suitable biochemical determinant for diagnosing late-onset hypogonadism syndrome.

Free testosterone by direct and calculated measurement versus equilibrium dialysis in a clinical population

INTRODUCTION

The value of clinically available free testosterone (FT) assays remains controversial. Here, we evaluate the agreement between the radioimmunoassay (RIA) and calculated FT (cFT) versus equilibrium dialysis (EqD), considered the gold standard.

METHODS

Fifty-six consecutive men (aged 26-77) had blood samples assessed for FT, including men with treated and untreated testosterone deficiency (TD) and men without TD. Samples were split and tested by the two methodologies at a Quest Diagnostics national reference laboratory. cFT was calculated by the Vermeulen method.

RESULTS

A robust correlation was noted for RIA and EqD (r = 0.966) and for cFT and EqD (r = 0.986). Strong correlations were observed for men receiving testosterone therapy and for men in the lowest and highest quartiles for total and FT. The correlation of total testosterone with FT was similar for cFT (r = 0.843), RIA (r = 0.806), and EqD (r = 0.809). Sex-hormone binding globulin (SHBG) was not correlated with any measure of FT. Bland-Altman analysis demonstrated similar bias for both cFT and RIA, although cFT consistently overestimated FT. Numerical values for RIA were approximately one seventh of EqD values.

CONCLUSIONS

These results support the clinical use of both RIA and cFT as measures of FT. Due to numerical differences, each test requires its own set of reference values.

Association of serum total testosterone concentration with skeletal muscle mass in men under hemodialysis

PURPOSE

Although skeletal muscle wasting can occur in chronic kidney diseases, its relationship with the serum testosterone concentration remains uncertain. This study investigates the relationship between serum testosterone and skeletal muscle mass in men under hemodialysis (HD).

METHODS

Sixty men aged between 41 and 89 years undergoing HD for 15.0 ± 8.1 years were enrolled for this study. The muscle areas of the thigh (TMA) and abdomen (AMA) were measured by computed tomography (CT), and the association between these muscle areas and serum total testosterone was examined with adjustment of age and other nutritional variables.

RESULTS

The mean serum total testosterone in our HD patients (6.33 ± 2.90 ng/mL) was not lower than that of the Japanese general population, but showed a positive correlation with TMA (r = 0.39, p < 0.05), AMA (r = 0.52, p < 0.001), serum creatinine (r = 0.33, p < 0.05), and the creatinine generation rate (r = 0.26, p < 0.05). Serum total testosterone was inversely correlated with age (r = -0.32, p < 0.05), CRP (r = -0.31, p < 0.05), and IL-6 (r = -0.24, p < 0.05). A multiple-regression analysis showed both serum total testosterone and age to be an independent determinant of the muscle mass in these patients.

CONCLUSIONS

This study identified testosterone as a determinant of muscle mass in HD men.

Free testosterone levels and implications on clinical outcomes in elderly men

BACKGROUND AND AIMS

Aging is accompanied by a progressive decline in serum testosterone. Evidence concerning the clinical manifestations of low serum testosterone levels is contradictory. We aimed to examine the age-related decline in testosterone and the possible clinical outcomes, including erectile dysfunction, prostatism, cognitive function, daily life activities, depression, and osteoporosis.

METHODS

One hundred and twenty men underwent comprehensive geriatric assessment. Testosterone and free testosterone levels were measured, geriatric assessment scales, International Index of Erectile Function (IIEF) and International Prostate Symptom Scale (IPSS) were performed, and bone mineral densities were determined.

RESULTS

The mean age of the 120 men was 73.8+/-5.90. A significant decrease in testosterone and free testosterone levels with increasing age was determined (p=0.021). It was also found that erectile dysfunction, as determined by IIEF (r=0.66, p<0.001), and symptoms of prostatism determined by IPSS (r=-0.23, p=0.016), were significantly associated with low free testosterone levels. Laboratory parameters, obesity, osteoporosis, cognitive function, daily life activities, and cardiovascular diseases were not significantly different between groups with low and normal free testosterone levels.

CONCLUSION

Age-related decrease in free testosterone may lead to erectile dysfunction and symptoms of prostatism in elderly men.

Low serum testosterone concentration in middle-aged men with type 2 diabetes

Low concentrations of endogenous androgens have been linked with insulin resistance and atherosclerosis. Men with diabetes have been reported to have lower serum testosterone concentration than non-diabetic men; however, there has never been a large study. The aim of this study was to investigate if endogenous androgen concentration is certainly lower in a relatively large number of Japanese patients with type 2 diabetes compared with healthy men, and to identify what factors may be associated with low serum testosterone concentrations in men with type 2 diabetes. Serum free testosterone concentrations were measured in 524 healthy men and in 331 consecutive Japanese men with type 2 diabetes between 40 and 69 years old. In addition, we investigated the relationships between serum free testosterone concentration and luteinizing hormone (LH) concentration as well as major cardiovascular risk factors including age, blood pressure, plasma lipid concentration, glycemic control (HbA(1c)), and BMI. Serum free testosterone concentrations were lower in men with type 2 diabetes than in healthy men in the 40-49 years group (10.9 +/- 3.3 vs. 14.0 +/- 3.6 pg/ml, P<0.0001), in the 50-59 years group (10.4 +/- 3.2 vs. 12.1 +/- 2.9 pg/ml, P<0.0001), and in the 60-69 years group (9.5 +/- 2.6 vs. 10.5 +/- 2.9 pg/ml, P = 0.0104). A negative correlation was found between serum free testosterone and LH concentrations (r = -0.326, P<0.0001). In conclusion, serum free testosterone concentration is certainly lower in a relatively large number of Japanese patients with type 2 diabetes compared with healthy men with each decade of life between 40 and 69 years old.

Age-related changes in serum testosterone and sex hormone binding globulin in Australian men: longitudinal analyses of two geographically separate regional cohorts

BACKGROUND

Cross-sectional studies from different populations show a variable decline in blood testosterone concentrations as men age. Few population representative cohorts have been followed up over time.

OBJECTIVE

The objective of the study was to quantify longitudinally the change in serum testosterone and SHBG concentrations with age in two well-defined, representative but geographically widely separated regional Australian cohorts.

SUBJECTS AND SETTING

The Busselton cohort comprises individuals aged 18-90 yr residing in Western Australia assessed prospectively since 1981. Sera were assayed from 910 men, from whom further samples were available 14 yr later in 480. The Dubbo cohort involves individuals aged 61-90 yr living in Eastern Australia. Baseline sera were collected from 610 men and additional sera on a second (n = 370) and third (n = 200) occasion from 1989 to 2004. Men from both cohorts are community dwelling and of predominately European origin.

RESULTS

Longitudinal analyses show the following: 1) total testosterone declines comparably (P > 0.9) by 1.3% (Busselton) and 0.9% (Dubbo) per annum with the same rates of decline when analyses were restricted to men older than 60 yr of age; 2) annual changes in SHBG were also very similar in age-restricted analyses (2.3% vs. 2.5%, P = 0.48); and 3) the annual increase in SHBG was steeper in middle-aged and older men (P < 10(-3) vs. young men). These longitudinal changes were all up to 4-fold greater in magnitude, compared with cross-sectional analyses of baseline data.

CONCLUSION

In two separate regional Australian populations, blood testosterone fell and SHBG increased comparably with age. Age-related changes in blood testosterone and SHBG previously described in urban-dwelling men are the same in men who reside in smaller regional cities of another continent.

Correlation Between the Aging Males’ Symptoms Scale and Sex Steroids, Gonadotropins, Dehydroepiandrosterone Sulfate, and Growth Hormone Levels in Ambulatory Men

INTRODUCTION

Partial androgen deficiency of the aging male (PADAM) is defined as a biochemical syndrome associated with advancing age that is characterized by a deficiency in serum androgen levels. The Aging Males' Symptoms (AMS) Scale was developed to evaluate PADAM-related symptoms and is currently used worldwide; however, it has been reported that PADAM-related symptoms evaluated by this scale are not related to serum testosterone levels. In addition to testosterone, the levels of other hormones also decrease with age; therefore, multihormone alterations may influence PADAM-related symptoms.

AIM

To investigate the relationship between PADAM-related symptoms evaluated by the AMS Scale and serum levels of testosterone, estradiol (E2), luteinizing hormone (LH), follicle-stimulating hormone (FSH), dehydroepiandrosterone sulfate (DHEA-S), and growth hormone (GH) in men.

METHODS

A total of 141 ambulatory men were recruited after excluding men with endocrine and other related diseases. All participants completed the AMS questionnaire and an analysis of serum levels of total and free testosterone (TT and FT), E2, LH, FSH, DHEA-S, and GH.

MAIN OUTCOME MEASURE

The relationship between AMS scores (total and subscores) and serum hormone levels was determined.

RESULTS

There were significant negative correlations between age and serum FT and DHEA-S levels, as well as positive correlations between age and serum LH and FSH levels, but no correlation between age and AMS scores. None of the three AMS domain scale scores and total scores significantly correlated with serum levels of TT, FT, E2, LH, FSH, DHEA-S, or GH.

CONCLUSIONS

The results of the present study suggest that PADAM-related symptoms as evaluated by the AMS Scale are not significantly related to serum levels of TT, FT, E2, LH, FSH, DHEA-S, or GH. Because many factors related to aging are thought to contribute to the occurrence of PADAM-related symptoms, the AMS Scale may not be able to predict serum hormone levels.