| 1. |
- Huhtaniemi, Ilpo T, et al.
(författare)
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Effect of Polymorphisms in Selected Genes Involved in Pituitary-Testicular Function on Reproductive Hormones and Phenotype in Aging Men.
- 2010
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 95, s. 1898-1908
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Tidskriftsartikel (refereegranskat)abstract
- Context: Polymorphisms in genes involved in regulation, biosynthesis, metabolism, and actions of testicular sex hormones may influence hormone balance and phenotype of aging men. Objective: We investigated the relationships between polymorphisms in genes related to pituitary-testicular endocrine function and health status. Design and Setting: Using cross-sectional baseline data, we conducted a multinational prospective cohort observational study consisting of a population survey of community-dwelling men. Participants: A total of 2748 men, aged 40-79 (mean +/- SD, 60.2 + 11.2) yr, were randomly recruited from eight European centers. Forty-three polymorphisms were genotyped in the following genes: androgen receptor (AR), estrogen receptor-alpha and -beta (ESR1 and ESR2), steroid 5alpha-reductase type II (SRD5A2), 17alpha-hydroxylase/17,20-lyase (CYP17A1), aromatase (CYP19A1), sex hormone-binding globulin (SHBG), LH beta-subunit (LHB), and LH receptor (LHCGR). Main Outcome Measures: We measured the associations between gene polymorphisms and endocrine, metabolic, and phenotypic parameters related to aging and sex hormone action. Results: Several polymorphisms in SHBG, ESR2, AR, CYP19A1, and LHB were significantly associated with circulating levels of SHBG, LH, total, free, and bioavailable testosterone and estradiol, the LH x testosterone product, and indices of insulin sensitivity. Apart from several previously reported associations between genes affecting estrogen levels and heel ultrasound parameters, no associations existed between polymorphisms and nonhormonal variables (anthropometry, blood lipids, blood pressure, hemoglobin, prostate symptoms, prostate-specific antigen, sexual dysfunction, cognition). Conclusion: In aging men, polymorphisms in genes related to the pituitary-testicular endocrine function significantly influence circulating LH, testosterone, and estradiol levels, but the downstream effects may be too small to influence secondary phenotypic parameters.
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| 2. |
- Lee, David M., et al.
(författare)
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Endogenous hormones, androgen receptor CAG repeat length and fluid cognition in middle-aged and older men: results from the European Male Ageing Study
- 2010
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Ingår i: European Journal of Endocrinology. - 1479-683X. ; 162:6, s. 1155-1164
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Data remain divergent regarding the activational effects of endogenous hormones on adult cognitive function. We examined the association between cognition, hormones and androgen receptor (AR) CAG repeat length in a large cohort of men. Design: Community-based, cross-sectional study of 3369 men aged 40-79 years. Methods: Cognition tests were the Rey-Osterrieth Complex Figure, Camden Topographical Recognition Memory and Digit-Symbol Substitution. A fluid cognition (FC) z-score was computed from the individual tests. Testosterone, oestradiol (OE2) and 5 alpha-dihydrotestosterone were measured by gas chromatography-mass spectrometry; DHEAS, LH, FSH and sex hormone-binding globulin (SHBG) by electrochemiluminescence. Free testosterone and OE2 were calculated from total hormone, SHBG and albumin. CAG repeat lengths were assayed by PCR genotyping. Results: Total testosterone and free testosterone were associated with higher FC z-scores, LH and FSH with lower FC z-scores in age-adjusted linear regressions. After adjusting for health, lifestyle and centre, a modest association was only observed between DHEAS and a lower FC z-score (beta=-0.011, P=0.02), although this was driven by subjects with DHEAS levels > 10 mu mol/l. Locally weighted plots revealed no threshold effects between hormones and FC. There was no association between CAG repeat length and FC z-score after adjustment for age and centre (beta=-0.007, P=0.06), nor any interaction effect between CAG repeat length and hormones. Conclusion: Our results suggest that endogenous hormones are not associated with a vision-based measure of FC among healthy, community-dwelling men. Further studies are warranted to determine whether 'high' DHEAS levels are associated with poorer performance on a broader range of neuropsychological tests.
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| 3. |
- Ohlsson, Claes, 1965, et al.
(författare)
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Low Serum Levels of Dehydroepiandrosterone Sulfate Predict All-Cause and Cardiovascular Mortality in Elderly Swedish Men
- 2010
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 95:9, s. 4406-4414
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Tidskriftsartikel (refereegranskat)abstract
- Context: The age-related decline in dehydroepiandrosterone (DHEA) levels is thought to be of importance for general and vascular aging. However, data on the association between DHEA and mortality are conflicting. Objectives: We tested the hypothesis that low serum DHEA and DHEA sulfate (DHEA-S) levels predict all-cause and cardiovascular disease (CVD) death in elderly men. Design, Setting, and Participants: We used gas/liquid chromatography-mass spectrometry to analyze baseline levels of DHEA and DHEA-S in the prospective population-based MrOS Sweden study (2644 men, aged 69-81 yr). Mortality data were obtained from central registers and analyzed using Cox proportional hazards regressions. Main Outcome Measures: All-cause and CVD mortality by serum DHEA(-S) levels. Results: During a mean 4.5-yr follow-up, 328 deaths occurred. Low levels of DHEA-S (quartile 1 vs. quartiles 2-4), predicted death from all causes [hazard ratio (HR) 1.54,95% confidence interval (CI) 1.21-1.96; adjusted for traditional cardiovascular risk factors], from CVD (n = 123 deaths; HR 1.61, 95% CI 1.10-2.37) and ischemic heart disease (n = 73; HR 1.67, 95% CI 1.02-2.74) but not cancer. Analyses with DHEA gave similar results. The association between low DHEA-S and CVD death remained after adjustment for C-reactive protein and circulating estradiol and testosterone levels. When stratified by the median age of 75.4 yr, the mortality prediction by low DHEA-S was more pronounced among younger (age adjusted HR for CVD death 2.64, 95% CI 1.37-5.09) than older men (HR 1.30, 95% CI 0.83-2.04). Conclusions: Low serum levels of DHEA(-S) predict death from all causes, CVD, and ischemic heart disease in older men.
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| 4. |
- Orwoll, Eric S., et al.
(författare)
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Evidence for Geographical and Racial Variation in Serum Sex Steroid Levels in Older Men
- 2010
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 95:10, s. E151-E160
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Tidskriftsartikel (refereegranskat)abstract
- Background: Despite considerable racial and geographical differences in human phenotypes and in the incidence of diseases that may be associated with sex steroid action, there are few data concerning variation in sex steroid levels among populations. We designed an international study to determine the degree to which geography and race influence sex steroid levels in older men. Methods: Using mass spectrometry, concentrations of serum androgens, estrogens, and sex steroid precursors/metabolites were measured in 5003 older men from five countries. SHBG levels were assessed using radioimmunoassay. Results: There was substantial geographical variation in the levels of sex steroids, precursors, and metabolites, as well as SHBG. For instance, Asian men in Hong Kong and Japan, but not in the United States, had levels of total testosterone approximately 20% higher than in other groups. Even greater variation was present in levels of estradiol, SHBG, and dihydrotestosterone. Group differences in body mass index did not explain most geographical differences. In addition, body mass index-independent racial differences were present; Black men had higher levels of estrogens (estradiol, estrone), and Asian men had lower levels of glucuronidated androgen metabolites. Conclusions: On a global scale, there are important geographical and racial differences in the concentrations of serum sex steroids and SHBG in older men.
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| 5. |
- Stener-Victorin, Elisabet, 1964, et al.
(författare)
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Are there any sensitive and specific sex steroid markers for polycystic ovary syndrome?
- 2010
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 95:2, s. 810-819
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Tidskriftsartikel (refereegranskat)abstract
- Context: Despite the high prevalence of hyperandrogenemia, the principal biochemical abnormality in women with polycystic ovary syndrome (PCOS), a definitive endocrine marker for PCOS has so far not been identified. Objective: To identify a tentative diagnostic marker for PCOS, we compared serum levels of sex steroids, their precursors, and main metabolites in women with PCOS and controls. Design and Methods: In this cross-sectional study of 74 women with PCOS and 31 controls, we used gas and liquid chromatography/mass spectrometry to analyze serum sex steroid precursors, estrogens, androgens, and glucuronidated androgen metabolites; performed immunoassays of SHBG, LH, and FSH; and calculated the LH/FSH ratio. Results: Androgens and estrogens, sex steroid precursors, and glucuronidated androgen metabolites were higher in women with PCOS than in controls. In multivariate logistic regression analyses, estrone and free testosterone were independently associated with PCOS. The odds ratios per sd increase were 24.2 for estrone [95% confidence interval (CI), 4.0-144.7] and 12.8 for free testosterone (95% CI, 3.1-53.4). In receiver operating characteristic analyses, the area under curve was 0.93 for estrone (95% CI, 0.88-0.98) and 0.91 for free testosterone (95% CI, 0.86-0.97), indicating high sensitivity and specificity. Conclusion: Women with PCOS have elevated levels of sex steroid precursors, estrogens, androgens, and glucuronidated androgen metabolites as measured with a specific and sensitive mass spectrometry-based technique. The combination of elevated estrone (>50 pg/ml) and free testosterone (>3.3 pg/ml) appeared to discriminate with high sensitivity and specificity between women with and without PCOS.
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| 6. |
- Tajar, Abdelouahid, et al.
(författare)
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Characteristics of Secondary, Primary, and Compensated Hypogonadism in Aging Men: Evidence from the European Male Ageing Study.
- 2010
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 95, s. 1810-1818
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Tidskriftsartikel (refereegranskat)abstract
- Context: The diagnosis of late-onset hypogonadism (LOH) in older men with age-related declines in testosterone (T) is currently not well characterized. Objective: Our objective was to investigate whether different forms of hypogonadism can be distinguished among aging men. Design: The study was a cross-sectional survey on 3369 community-dwelling men aged 40-79 yr in eight European centers. Methods: Four groups of subjects were defined: eugonadal (normal T and normal LH), secondary (low T and low/normal LH), primary (low T and elevated LH), and compensated (normal T and elevated LH) hypogonadism. Relationships between the defined gonadal status with potential risk factors and clinical symptoms were investigated by multilevel regression models. Results: Among the men, 11.8, 2.0, and 9.5% were classified into the secondary, primary, and compensated hypogonadism categories, respectively. Older men were more likely to have primary [relative risk ratio (RRR) = 3.04; P < 0.001] and compensated (RRR = 2.41; P < 0.001) hypogonadism. Body mass index of 30 kg/m(2) or higher was associated with secondary hypogonadism (RRR = 8.74; P < 0.001). Comorbidity was associated with both secondary and primary hypogonadism. Sexual symptoms were more prevalent in secondary and primary hypogonadism, whereas physical symptoms were more likely in compensated hypogonadism. Conclusions: Symptomatic elderly men considered to have LOH can be differentiated on the basis of endocrine and clinical features and predisposing risk factors. Secondary hypogonadism is associated with obesity and primary hypogonadism predominately with age. Compensated hypogonadism can be considered a distinct clinical state associated with aging. Classification of LOH into different categories by combining LH with T may improve the diagnosis and management of LOH.
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| 7. |
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| 8. |
- Vandenput, Liesbeth, et al.
(författare)
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Serum estradiol is associated with lean mass in elderly Swedish men
- 2010
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Ingår i: European Journal of Endocrinology. - 0804-4643 .- 1479-683X. ; 162:4, s. 737-745
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Association studies in men have shown that androgens are inversely related to fat measures, while the relation between sex steroids and lean mass remains unclear. We, therefore, investigated the associations between serum sex steroid levels and body composition in elderly men with a main focus on lean mass measures. DESIGN AND METHODS: A cross-sectional survey of a population-based cohort of 3014 elderly men, aged 69-80 years (Osteoporotic Fractures in Men study, Sweden). Serum levels of testosterone and estradiol (E(2)) were measured by mass spectrometry, sex hormone-binding globulin (SHBG) levels were measured by IRMA, and measures of body composition were obtained by dual-energy X-ray absorptiometry. RESULTS: Total as well as free serum testosterone associated independently inversely (P<0.001), while total as well as free serum E(2) associated independently directly (P<0.001) with total body fat mass and trunk fat mass. Serum SHBG associated independently inversely with central fat distribution. Serum E(2) and free E(2) but not serum testosterone or free testosterone levels associated positively with lean mass (P<0.01). Elderly men within the lowest quartile of free E(2) had 0.5 kg less lean mass in the legs than subjects within the highest quartile, while the subjects in the different quartiles of free testosterone did not differ in lean mass. CONCLUSIONS: Serum E(2), but not serum testosterone, is directly associated with lean mass in this large study of elderly Swedish men. In addition, serum SHBG is associated with central fat distribution and we confirmed that serum testosterone is inversely associated with fat mass.
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| 9. |
- Wu, Frederick C. W., et al.
(författare)
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Identification of Late-Onset Hypogonadism in Middle-Aged and Elderly Men
- 2010
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Ingår i: New England Journal of Medicine. - 1533-4406 .- 0028-4793. ; 363:2, s. 123-135
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Konferensbidrag (refereegranskat)abstract
- BACKGROUND The association between aging-related testosterone deficiency and late-onset hypogonadism in men remains a controversial concept. We sought evidence-based criteria for identifying late-onset hypogonadism in the general population on the basis of an association between symptoms and a low testosterone level. METHODS We surveyed a random population sample of 3369 men between the ages of 40 and 79 years at eight European centers. Using questionnaires, we collected data with regard to the subjects' general, sexual, physical, and psychological health. Levels of total testosterone were measured in morning blood samples by mass spectrometry, and free testosterone levels were calculated with the use of Vermeulen's formula. Data were randomly split into separate training and validation sets for confirmatory analyses. RESULTS In the training set, symptoms of poor morning erection, low sexual desire, erectile dysfunction, inability to perform vigorous activity, depression, and fatigue were significantly related to the testosterone level. Increased probabilities of the three sexual symptoms and limited physical vigor were discernible with decreased testosterone levels (ranges, 8.0 to 13.0 nmol per liter [2.3 to 3.7 ng per milliliter] for total testosterone and 160 to 280 pmol per liter [46 to 81 pg per milliliter] for free testosterone). However, only the three sexual symptoms had a syndromic association with decreased testosterone levels. An inverse relationship between an increasing number of sexual symptoms and a decreasing testosterone level was observed. These relationships were independently confirmed in the validation set, in which the strengths of the association between symptoms and low testosterone levels determined the minimum criteria necessary to identify late-onset hypogonadism. CONCLUSIONS Late-onset hypogonadism can be defined by the presence of at least three sexual symptoms associated with a total testosterone level of less than 11 nmol per liter (3.2 ng per milliliter) and a free testosterone level of less than 220 pmol per liter (64 pg per milliliter).
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