Lifestyle factors and serum androgens among 636 middle aged men from seven countries in the European Prospective Investigation into Cancer and Nutrition (EPIC)

Dietary fat quality and serum androgen concentrations in middle-aged men

BACKGROUND/OBJECTIVES

Average testosterone concentrations in men have declined over the last few decades. The reasons for this are not fully known, but changes in dietary fat quality have been suggested to have a role. This study aimed to investigate the associations of different dietary fatty acids with serum androgen concentrations.

SUBJECTS/METHODS

A total of 2546 men with a mean age of 53 from the Kuopio Ischaemic Heart Disease Risk Factor Study were included in this cross-sectional study. Associations between dietary saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA) and trans (TFA) fatty acids and concentrations of serum total and free testosterone and steroid hormone binding globulin (SHBG) were analyzed with analysis of covariance and linear regression analysis. Associations of isocaloric replacement of nutrients and androgen concentrations were analyzed with multivariate nutrient-density models.

RESULTS

After adjustment for age, examination year and energy intake, higher SFA intake was associated with higher serum total and free testosterone and SHBG concentrations, and higher PUFA intake with lower concentrations. However, the associations were attenuated and not statistically significant after further adjustments for potential confounders. MUFA and TFA intakes were not associated with androgen concentrations. In isocaloric substitution models, replacing dietary protein with SFA was associated with higher serum total testosterone and SHBG concentrations. After excluding men with history of CVD or diabetes (n = 1021), no statistically significant associations were found.

CONCLUSIONS

Dietary fat quality was not independently associated with serum androgen concentrations in middle-aged men. However, replacing protein with SFA may be associated with higher serum androgen concentrations.

An epigenome-wide analysis of sex hormone levels and DNA methylation in male blood samples

Endogenous sex hormones and DNA methylation both play important roles in various diseases. However, their interplay is largely unknown. A deeper understanding of their interrelationships could provide new insights into the pathology of disease development. We, therefore, investigated associations between circulating sex hormones, sex hormone binding globulin (SHBG), and DNA methylation in blood, using samples from 77 men (65 with repeated samples), from the population-based Northern Sweden Health and Disease Study (NSHDS). DNA methylation was measured in buffy coat using the Infinium Methylation EPIC BeadChip (Illumina). Sex hormone (oestradiol, oestrone, testosterone, androstenedione, dehydroepiandrosterone, and progesterone) and SHBG concentrations were measured in plasma using a high-performance liquid chromatography tandem mass spectrometry (LC/MS-MS) method and an enzyme-linked immunoassay, respectively. Associations between sex hormones, SHBG, and DNA methylation were estimated using both linear regression and mixed-effects models. Additionally, we used the comb-p method to identify differentially methylated regions based on nearby P values. We identified one novel CpG site (cg14319657), at which DNA methylation was associated with dehydroepiandrosterone, surpassing a genome-wide significance level. In addition, more than 40 differentially methylated regions were associated with levels of sex hormones and SHBG and several of these mapped to genes involved in hormone-related diseases. Our findings support a relationship between circulating sex hormones and DNA methylation and suggest that further investigation is warranted, both for validation, further exploration and to gain a deeper understanding of the mechanisms and potential consequences for health and disease.

Association between metabolic syndrome, hepatic steatosis, and testosterone deficiency: evidences from studies with men and rodents

Testosterone is the predominant androgen in men and the lack of it can be a trigger to the development of the metabolic syndrome. Here we review the relationship between testosterone deficiency, metabolic syndrome, and hepatic steatosis reported by studies with men and rodents. The prevalence of metabolic syndrome and testosterone deficiency is higher among older subjects. Low total and free testosterone levels were positively associated with disturbs on energy metabolism, changes in body fat distribution, and body composition. Studies reported visceral fat accumulation in men with hypogonadism and castrated rats. Despite some contradictions, the association between higher adiposity, low testosterone, and metabolic syndrome was a common point among the studies. Few studies evaluated the hepatic steatosis and found an association with hypogonadism. Most of the studies with rodents combined the castration with a high-fat diet to study metabolic disturbs. The importance of proper levels of testosterone for energy metabolism homeostasis in men was also underlined by studies that investigated the metabolic effects of testosterone replacement therapy and androgen deprivation therapy.

The severity of hypogonadism symptoms and its risk factors among male employees of Tehran University of Medical Sciences

OBJECTIVES

The current study was conducted to examine the severity of hypogonadism symptoms and their risk factors among the male employees of Tehran University of Medical Sciences (TUMS).

METHODS

This cross-sectional study was conducted on 80 male employees aged 40-60 years, with hypogonadism, at TUMS. The participants were selected through census sampling. The data collection tools included the demographic questionnaire and the Aging Male Symptoms (AMS) questionnaire. The participants first completed the demographic questionnaire and then the AMS questionnaire. SPSS statistical software version 22 (Chicago, IL) was used to analyze the data, and one-way ANOVA tests, Pearson's correlation coefficient, and stepwise multivariate logistic regression were applied.

RESULTS

Based on our findings, the mean overall score of hypogonadism symptoms was 41.71 ± 9.20. Based on Pearson's correlation coefficient results, there was a statistically significant association between the severity of hypogonadism symptoms and age (p < .001). Furthermore, there were significant associations between the economic status, cigarette consumption and hours of sleep and the severity of hypogonadism symptoms (p < .001).

CONCLUSIONS

The current study's results showed that certain factors can affect hypogonadism in males. Thus, it is important to reduce the severity of hypogonadism symptoms and to modify the factors related to this phenomenon.

Cross-sectional association of coffee and caffeine consumption with sex hormone-binding globulin in healthy nondiabetic women

OBJECTIVE

Low sex hormone-binding globulin (SHBG) is a consistent risk factor for type 2 diabetes, particularly in women. Coffee consumption has been associated with a lower risk of type 2 diabetes, but its effects on SHBG are less known.

DESIGN AND METHODS

This was a cross-sectional study of 2377 nondiabetic pre- and postmenopausal women from the E3N cohort study whose baseline SHBG was measured. Information on diet (including coffee and caffeine consumption), lifestyle and medical conditions was collected through questionnaires. The relationship between coffee and caffeine consumption and SHBG was modelled, with adjustment for covariates and stratification by body mass index (BMI) categories (< or ≥25 kg/m² ) and menopausal status.

RESULTS

The mean age was 57.2±6.4 years and 61% of the 2377 women were postmenopausal. High coffee (≥3 cups/day) and caffeine (≥265 mg/day) intakes were associated with a reduced risk of being in the 1st quartile of the SHBG level distribution (<46.3 nmol/L) in a multivariate adjusted model (OR: 0.72 [95% CI: 0.52-1.01] and OR: 0.71 [95% CI: 0.53-0.95], respectively). No association was found between tea consumption and SHBG levels. In multivariate models stratified on BMI categories and menopausal status, associations were restricted to women with a BMI ≥25 kg/m² or being postmenopausal. The association with SHBG was consistently noted with consumption of both caffeinated coffee and caffeine, but not decaffeinated coffee.

CONCLUSIONS

Consumption of high coffee and caffeine is associated with a reduced risk of low SHBG, an established risk marker for T2DM, which might contribute to the protective effects of coffee for type 2 diabetes.

Sex-specific metabolic profiles of androgens and its main binding protein SHBG in a middle aged population without diabetes

The role of androgens in metabolism with respect to sex-specific disease associations is poorly understood. Therefore, we aimed to provide molecular signatures in plasma and urine of androgen action in a sex-specific manner using state-of-the-art metabolomics techniques. Our study population consisted of 430 men and 343 women, aged 20-80 years, who were recruited for the cross-sectional population-based Study of Health in Pomerania (SHIP-TREND), Germany. We used linear regression models to identify associations between testosterone, androstenedione and dehydroepiandrosterone-sulfate (DHEAS) as well as sex hormone-binding globulin and plasma or urine metabolites measured by mass spectrometry. The analyses revealed major sex-specific differences in androgen-associated metabolites, particularly for levels of urate, lipids and metabolic surrogates of lifestyle factors, like cotinine or piperine. In women, in particular in the postmenopausal state, androgens showed a greater impact on the metabolome than in men (especially DHEAS and lipids were highly related in women). We observed a novel association of androstenedione on the metabolism of biogenic amines and only a small sex-overlap of associations within steroid metabolism. The present study yields new insights in the interaction between androgens and metabolism, especially about their implication in female metabolism.

Normalization of Testosterone Levels After Testosterone Replacement Therapy Is Not Associated With Reduced Myocardial Infarction in Smokers

Objective

To examine the effect of cigarette smoking (CS) status and total testosterone (TT) levels after testosterone replacement therapy (TRT) on all-cause mortality, myocardial infarction (MI), and stroke in male smokers and nonsmokers without history of MI and stroke.

Participants and Methods

Data from 18,055 males with known CS status and low TT levels who received TRT at the Veterans Health Administration between December 1, 1999, and May 31, 2014, were grouped into (1) current smokers with normalized TT, (2) current smokers with nonnormalized TT, (3) nonsmokers with normalized TT, and (4) nonsmokers with nonnormalized TT. Combined effect of CS status and TT level normalization after TRT on all-cause mortality, MI, and stroke was compared using propensity score–weighted Cox proportional hazard models.

Results

Normalization of serum TT levels in nonsmokers was associated with a significant decrease in all-cause mortality (hazard ratio [HR]=0.526; 95% CI, 0.477-0.581; P<.001) and MI (HR=0.717; 95% CI, 0.522-0.986; P<.001). Among current smokers, normalization of serum TT levels was associated with a significant decrease in only all-cause mortality (HR=0.563; 95% CI, 0.488-0.649; P<.001) without benefit in MI (HR=1.096; 95% CI, 0.698-1.720; P=.69). Importantly, compared with nonsmokers with normalized TT, all-cause mortality (HR=1.242; 95% CI, 1.104-1.396; P<.001), MI (HR=1.706; 95% CI, 1.242-2.342; P=.001), and stroke (HR=1.590; 95% CI, 1.013-2.495; P=.04) were significantly higher in current smokers with normalized TT.

Conclusion

We conclude that active CS may negate the protective effect of testosterone level normalization on all-cause mortality and MI after TRT.

Cigarette smoking and testosterone in men and women: A systematic review and meta-analysis of observational studies

Recently Health Canada and the Food and Drug Administration warned about the cardiovascular risk of testosterone, making environmental drivers of testosterone potential prevention targets. Cotinine, a tobacco metabolite, inhibits testosterone breakdown. We assessed the association of smoking with testosterone in a systematic review and meta-analysis, searching PubMed and Web of Science through March 2015 using ("testosterone" or "androgen" or "sex hormone") and ("smoking" or "cigarette"). Two reviewers independently searched, selected, assessed quality and abstracted with differences resolved by consensus or reference to a third reviewer. The initial search yielded 2881 studies; 28 met the selection criteria. In 22 studies of 13,317 men, mean age 18-61years, smokers had higher mean testosterone than non-smokers (1.53nmol/L, 95% confidence interval (CI) 1.11 to 1.96) using a random effects model with inverse variance weighting. In 6 studies of 6089 women, mean age 28-62years, smoking was not clearly associated with testosterone (0.11nmol/L, 95% CI -0.08 to 0.30). Fixed effects models provided similar results, but suggested a positive association in women. Whether products which raise cotinine, such as e-cigarettes or nicotine replacement, also raise testosterone, should be investigated, to inform any regulatory action for e-cigarettes, which emit nicotine into the surrounding air, with relevance for both active and passive smokers.

Cancer chemoprevention with nuts

It is well established that increased nut consumption is associated with a reduced risk of major chronic diseases, such as cardiovascular disease and type 2 diabetes mellitus. On the other hand, the association between nut consumption and cancer mortality is less clear. Recent studies have suggested that nut consumption is associated with reduced cancer mortality. This evidence reinforces the interest to investigate the chemopreventive properties of nuts, and it raises questions about the specific cancer type(s) and setting that can be more affected by nut consumption, as well as the cellular mechanisms involved in this protective effect. Here we discuss recent studies on the association of nut consumption and cancer, and we propose specific cellular mechanisms by which nut components can affect cancer progression.

Androgen activity, ischaemic heart disease and risk factors among men in NHANES III

AIM

Observationally, low serum testosterone among men is associated with cardiovascular diseases and its risk factors, but it is unclear whether raising endogenous androgens would be protective. To clarify the role of androgens, the association of two different androgen biomarkers (serum testosterone and androstanediol glucuronide) with cardiovascular disease risk factors and mortality was examined in a nationally representative sample of US men.

RESEARCH DESIGN AND METHODS

Multivariable linear and proportion hazards regression were used to examine the adjusted associations of serum testosterone and androstanediol glucuronide with cardiovascular disease risk factors and death from major cardiovascular diseases in 1460 men from NHANES III phase 1 (1988-1991) followed-up through 2006.

RESULTS

Serum testosterone and androstanediol glucuronide were weakly correlated (0·13). Serum testosterone was associated with healthier values of most cardiovascular disease risk factors but not with death from ischaemic heart disease or stroke, adjusted for age, education, race/ethnicity, smoking and alcohol use. Similarly adjusted, androstanediol glucuronide was associated with unhealthier values of some cardiovascular risk factors and death from ischaemic heart disease (hazard ratio 1·16, 95% confidence interval 1·003-1·33 per standard deviation).

CONCLUSIONS

Androgen biomarkers had inconsistent associations with cardiovascular disease risk factors and ischaemic heart disease. Androstanediol glucuronide, rather than serum testosterone, had associations with cardiovascular disease risk factors more similar to those seen in randomized controlled trials of testosterone therapy, with corresponding implications for raising androgens.

Androgen activity and markers of inflammation among men in NHANES III

OBJECTIVES

Inflammation contributes to chronic diseases. Lower serum testosterone among men is associated with less inflammation, yet immune defense is thought to trade-off against reproduction with androgens adversely affecting immune function. Anti-androgens are effective at castrate levels of serum testosterone, suggesting serum testosterone may not capture all androgen activity. The association of two androgen biomarkers with key markers of inflammation was examined.

METHODS

The adjusted association of serum testosterone and androstanediol glucuronide with C-reactive protein, white blood cell, granulocyte and lymphocyte count, fibrinogen, and hemoglobin, as a control outcome because testosterone administration raises hemoglobin, were examined in a nationally representative sample of 1,490 US men from the National Health and Nutrition Examination Survey III phase 1 (1988-1991) using multivariable linear regression.

RESULTS

Serum testosterone and androstanediol glucuronide were weakly correlated (0.13). Serum testosterone was associated with lower white blood cell count [-0.26 × 10(-9) per standard deviation, 95% confidence interval (CI) -0.37 to -0.14] and granulocyte count (-0.21 × 10(-9) , 95% CI -0.29 to -0.13) but not with hemoglobin (0.02 g/l, 95% CI -0.89 to 0.92), adjusted for age, education, race/ethnicity, smoking, and alcohol. Similarly adjusted, androstanediol glucuronide was not associated with white blood cell count (0.10 × 10(-9) , 95% CI -0.05 to -0.25), granulocyte count (0.12 × 10(-9) , 95% CI -0.02 to 0.25), or fibrinogen (0.05 g/l, 95% CI -0.004 to 0.11), but was with hemoglobin (0.70 g/l, 95% CI 0.07 to 1.32).

CONCLUSIONS

Different androgen biomarkers had different associations with inflammatory markers, highlighting the need to consider several androgen biomarkers. The possibility remains that androgens may generate inflammatory processes with implications for chronic diseases.

The relationship of appetitive, reproductive and posterior pituitary hormones to alcoholism and craving in humans

A significant challenge for understanding alcoholism lies in discovering why some, but not other individuals, become dependent on alcohol. Genetic, environmental, cultural, developmental, and neurobiological influences are recognized as essential factors underlying a person's risk for becoming alcohol dependent (AD); however, the neurobiological processes that trigger this vulnerability are still poorly understood. Hormones are important in the regulation of many functions and several hormones are strongly associated with alcohol use. While medical consequences are important, the primary focus of this review is on the underlying confluence of appetitive/feeding, reproductive and posterior pituitary hormones associated with distinct phases of alcoholism or assessed by alcohol craving in humans. While these hormones are of diverse origin, the involvement with alcoholism by these hormone systems is unmistakable, and demonstrates the complexity of interactions with alcohol and the difficulty of successfully pursuing effective treatments. Whether alcohol associated changes in the activity of certain hormones are the result of alcohol use or are the result of an underlying predisposition for alcoholism, or a combination of both, is currently of great scientific interest. The evidence we present in this review suggests that appetitive hormones may be markers as they appear involved in alcohol dependence and craving, that reproductive hormones provide an example of the consequences of drinking and are affected by alcohol, and that posterior pituitary hormones have potential for being targets for treatment. A better understanding of the nature of these associations may contribute to diagnosing and more comprehensively treating alcoholism. Pharmacotherapies that take advantage of our new understanding of hormones, their receptors, or their potential relationship to craving may shed light on the treatment of this disorder.

A cross-sectional study of the association of age, race and ethnicity, and body mass index with sex steroid hormone marker profiles among men in the National Health and Nutrition Examination Survey (NHANES III)

OBJECTIVES

Since sex hormone markers are metabolically linked, examining sex steroid hormones singly may account for inconsistent findings by age, race/ethnicity and body mass index (BMI) across studies. First, these markers were statistically combined into profiles to account for the metabolic relationship between markers. Then, the relationships between sex steroid hormone profiles and age, race/ethnicity and BMI were explored in multinomial logistic regression models.

DESIGN

Cross-sectional survey.

SETTING

The US Third National Health and Nutrition Examination Survey (NHANES III).

PARTICIPANTS

1538 Men, >17 years.

PRIMARY OUTCOME MEASURE

Sex hormone profiles.

RESULTS

Cluster analysis was used to identify four statistically determined profiles with Blom-transformed T, E, sex hormone binding globulin (SHBG), and 3-α diol G. We used these four profiles with multinomial logistic regression models to examine differences by race/ethnicity, age and BMI. Mexican American men >50 years were associated with the profile that had lowest T, E and 3-α diol G levels compared to other profiles (p<0.05). Non-Hispanic Black, overweight (25-29.9 kg/m(2)) and obese (>30 kg/m(2)) men were most likely to be associated with the cluster with the lowest SHBG (p<0.05).

CONCLUSION

The associations of sex steroid hormone profiles by race/ethnicity are novel, while the findings by age and BMI groups are largely consistent with observations from single hormone studies. Future studies should validate these hormone profile groups and investigate these profiles in relation to chronic diseases and certain cancers.

The effects of bed-rest and countermeasure exercise on the endocrine system in male adults: evidence for immobilization-induced reduction in sex hormone-binding globulin levels

BACKGROUND AND AIM

There is limited data on the effects of inactivity (prolonged bed-rest) on parameters of endocrine and metabolic function; we therefore aimed to examine changes in these systems during and after prolonged (56- day) bed-rest in male adults.

SUBJECTS AND METHODS

Twenty healthy male subjects underwent 8 weeks of strict bed-rest and 12 months of follow-up as part of the Berlin Bed Rest Study. Subjects were randomized to an inactive group or a group that performed resistive vibration exercise (RVE) during bed-rest. All outcome parameters were measured before, during and after bed-rest. These included body composition (by whole body dual X-ray absorptiometry), SHBG, testosterone (T), estradiol (E2), PRL, cortisol (C), TSH and free T3 (FT3).

RESULTS

Serum SHBG levels decreased in inactive subjects but remained unchanged in the RVE group (p<0.001). Serum T concentrations increased during the first 3 weeks of bed-rest in both groups (p<0.0001), while E2 levels sharply rose with re-mobilization (p<0.0001). Serum PRL decreased in the control group but increased in the RVE group (p=0.021). C levels did not change over time (p≥0.10). TSH increased whilst FT3 decreased during bed-rest (p all ≤0.0013).

CONCLUSIONS

Prolonged bed-rest has significant effects on parameters of endocrine and metabolic function, some of which are related to, or counteracted by physical activity.

Trends in sex hormone concentrations in US males: 1988-1991 to 1999-2004

Previous studies suggest that male testosterone concentrations have declined over time. To explore this in a large US population, we examined testosterone and free testosterone concentrations in National Health and Nutrition Examination Surveys (NHANES) from 1988-1991 and 1999-2004. We also examined sex hormone-binding globulin (SHBG), estradiol, and androstanediol glucuronide (3α-diol-G) over the same period. Non-Hispanic white, non-Hispanic black, and Mexican-American men from 1988-1991 and 1999-2004 NHANES surveys who were ≥20 years old and had serum from morning blood draws were included in this analysis (1988-1991: N = 1,413; 1999-2004: N = 902). Testosterone, estradiol and SHBG were measured by competitive electrochemiluminescence immunoassays and 3α-diol-G was measured by enzyme immunoassay. Free testosterone was calculated using testosterone and SHBG values. Adjusted mean hormone concentrations were estimated using linear regression, accounting for NHANES sampling weights and design, age, race/ethnicity, body mass index, waist circumference, alcohol use and smoking. Differences in adjusted mean concentrations (Δ) and two-sided p-values were calculated; p < 0.05 was statistically significant. Overall, 3α-diol-G and estradiol declined between 1988-1991 and 1999-2004, but there was little change in testosterone, free testosterone, or SHBG (Δ: 3α-diol-G = -1.83 ng/mL, p < 0.01; estradiol = -6.07 pg/mL, p < 0.01; testosterone = -0.03 ng/mL, p = 0.75; free testosterone = -0.001 ng/mL, p = 0.67; SHBG = -1.17 nmol/L, p = 0.19). Stratification by age and race revealed that SHBG and 3α-diol-G declined among whites 20-44 years old (Δ: SHBG = -5.14 nmol/L, p < 0.01; 3α-diol-G = -2.89 ng/mL, p < 0.01) and free testosterone increased among blacks 20-44 years old (Δ: 0.014 ng/mL, p = 0.03). Estradiol declined among all ages of whites and Mexican-Americans. In conclusion, there was no evidence for testosterone decline between 1988-1991 and 1999-2004 in the US general population. Subgroup analyses suggest that SHBG and 3α-diol-G declined in young white men, estradiol declined in white and Mexican-American men, and free testosterone increased in young black men. These changes may be related to the increasing prevalence of reproductive disorders in young men.

Sex hormone activity in alcohol addiction: integrating organizational and activational effects

There are well-known sex differences in the epidemiology and etiopathology of alcohol dependence. Male gender is a crucial risk factor for the onset of alcohol addiction. A directly modifying role of testosterone in alcohol addiction-related behavior is well established. Sex hormones exert both permanent (organizational) and transient (activational) effects on the human brain. The sensitive period for these effects lasts throughout life. In this article, we present a novel early sex hormone activity model of alcohol addiction. We propose that early exposure to sex hormones triggers structural (organizational) neuroadaptations. These neuroadaptations affect cellular and behavioral responses to adult sex hormones, sensitize the brain's reward system to the reinforcing properties of alcohol and modulate alcohol addictive behavior later in life. This review outlines clinical findings related to the early sex hormone activity model of alcohol addiction (handedness, the second-to-fourth-finger length ratio, and the androgen receptor and aromatase) and includes clinical and preclinical literature regarding the activational effects of sex hormones in alcohol drinking behavior. Furthermore, we discuss the role of the hypothalamic-pituitary-adrenal and -gonadal axes and the opioid system in mediating the relationship between sex hormone activity and alcohol dependence. We conclude that a combination of exposure to sex hormones in utero and during early development contributes to the risk of alcohol addiction later in life. The early sex hormone activity model of alcohol addiction may prove to be a valuable tool in the development of preventive and therapeutic strategies.

Associations of birth weight and physical activity with sex steroids in preschool Japanese children

PURPOSE

We aimed to assess the association of body size at birth or physical activity with sex steroid levels, independent of body mass among young children.

METHODS

The cross-sectional study was conducted in 2006. Subjects were 230 boys and 198 girls, aged 3-6 years. Birth weight was based on parents' reports. Questions about physical activity focused on outdoor playtime. Urinary estrone, estradiol, testosterone, and 5-androstene-3β,17α diol (3β,17α-AED) levels were measured by liquid chromatography-electrospray ionization tandem mass spectrometry. Urinary dehydroepiandrosterone level was measured with a radioimmunoassay.

RESULTS

After adjustments for age and BMI, girls with lower birth weight had higher testosterone (trend p = 0.038) and 3β,17α-AED (trend p = 0.028). Girls with low birth weight and high birth weight had higher estrone (p = 0.014) and estradiol (p = 0.074) than those who had middle birth weight. Boys who were physically active had lower testosterone (p = 0.028) and 3β,17α-AED (p = 0.003) than those who were not active. Girls who were physically active had lower estrone (p = 0.015).

CONCLUSIONS

Sex steroid levels in childhood might be affected by body size at birth or by physical activity during childhood. These effects might differ by sex.

Body fatness and sex steroid hormone concentrations in US men: results from NHANES III

OBJECTIVE

Obesity is associated with a variety of chronic diseases, including cancer, which may partly be explained by its influence on sex steroid hormone concentrations. Whether different measures of obesity, i.e., body mass index (BMI), waist circumference, and percent body fat were differentially associated with circulating levels of sex steroid hormones was examined in 1,265 men, aged 20-90+ years old, attending the morning examination session of the Third National Health and Nutrition Examination Survey (NHANES III).

MATERIALS AND METHODS

Serum hormones were measured by immunoassay. Weight, height, and waist circumference were measured by trained staff. Percent body fat was estimated from bioelectrical impedance. Multivariate linear regression was used to estimate associations between body fatness measures and hormone levels.

RESULTS

Total and free testosterone and sex hormone binding globulin concentrations decreased, whereas total and free estradiol increased with increasing BMI, waist circumference, and percent body fat (all p trend < 0.05). The magnitude of change in these hormones was similar for a one-quartile increase in each body fatness measure.

CONCLUSION

Measured BMI, waist circumference, and percent body fat led to similar inferences about their association with hormone levels in men.

Associations of endogenous testosterone and SHBG with glycated haemoglobin in middle-aged and older men

OBJECTIVE

Low circulating levels of testosterone and sex-hormone-binding globulin (SHBG) are associated with increased cardiovascular risk in men. This association may be partially mediated through changes in glucose metabolism, but relatively few data are available on the relationship between sex hormones and markers of long-term glycaemia. We assessed the associations of endogenous testosterone and SHBG with glycated haemoglobin (HbA(1c) ) in men.

DESIGN AND SUBJECTS

Cross-sectional study of 1292 men from the Norfolk population of European Prospective Investigation into Cancer (EPIC-Norfolk).

MEASUREMENTS

Glycated haemoglobin, total testosterone (TT) and SHBG levels were measured, and free testosterone (FT) levels were calculated. Multiple linear regression models were used to assess the associations of TT, SHBG and FT with HbA(1c).

RESULTS

Men with diabetes had lower testosterone and SHBG levels. In non-diabetic men, HbA(1c) levels were inversely associated with TT and calculated FT independently of age, body mass index, smoking, alcohol consumption and physical activity. The adjusted change in HbA(1c) was 0·055 (95% CI 0·025; 0·085) per standard deviation (SD) decrease in TT and 0·041 (95% CI 0·010; 0·073) per SD decrease in calculated FT, respectively. SHBG levels were inversely associated with HbA(1c) after multivariable adjustment (β = 0·038 per SD decrease (95% CI 0·004; 0·071)).

CONCLUSIONS

In middle-aged and older men, low endogenous testosterone and SHBG levels are associated with glycaemia, even below the threshold for diabetes. Further studies are needed to determine the effects of interventions that raise testosterone levels in men having increased HbA(1c) and subnormal testosterone levels.

Do male lymphoma survivors have impaired sexual function?

PURPOSE

Sexual function in male lymphoma survivors was examined and compared with that of age-matched controls.

PATIENTS AND METHODS

This cross-sectional study included serum gonadal hormone levels (testosterone, sex hormone-binding globulin, luteinizing hormone [LH], and follicle-stimulating hormone) and responses to questionnaires assessing sexual function (Brief Sexual Function Inventory [BSFI]), socioeconomic factors, quality of life, emotional distress, and fatigue. The lymphoma group included 246 men < or = 50 years old at diagnosis who were diagnosed from 1980 to 2002 and treated at the Norwegian Radium Hospital. For each lymphoma survivor, two age-matched controls (n = 492) were drawn from a normative sample with BSFI scores.

RESULTS

The lymphoma survivors had a mean age at survey of 47.4 years, the mean duration of follow-up was 14.8 years, and 79% lived in committed relationships. All BSFI domain scores decreased significantly with age. Lymphoma survivors having low testosterone and/or elevated LH had lower BSFI scores than survivors with normal gonadal hormones. Multivariate analyses showed that increasing age, more emotional distress, poor physical health, and low testosterone and/or elevated LH were significantly associated with reduced sexual function within the lymphoma group. Lymphoma survivors had significantly lower BSFI domain scores than did controls on erection, ejaculation, and sexual satisfaction.

CONCLUSION

Lymphoma survivors had significantly poorer sexual function than normative controls. It is unclear whether the abnormal hormone levels directly cause the reduced sexual function within the lymphoma group or if a mediating factor is involved, such as aging, emotional distress, or perceived health status.