scholarly journals Age-Related Changes in Serum Testosterone and Sex Hormone Binding Globulin in Australian Men: Longitudinal Analyses of Two Geographically Separate Regional Cohorts

2007 ◽  
Vol 92 (9) ◽  
pp. 3599-3603 ◽  
Author(s):  
Peter Y. Liu ◽  
Jonathan Beilin ◽  
Christian Meier ◽  
Tuan V. Nguyen ◽  
Jacqueline R. Center ◽  
...  

Abstract 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 < 10−3vs. 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.

2007 ◽  
Vol 156 (5) ◽  
pp. 585-594 ◽  
Author(s):  
Bu B Yeap ◽  
Osvaldo P Almeida ◽  
Zoë Hyde ◽  
Paul E Norman ◽  
S A Paul Chubb ◽  
...  

Objective: An age-related decline in serum total and free testosterone concentration may contribute to ill health in men, but limited data are available for men > 70 years of age. We sought to determine the distribution and associations of reduced testosterone concentrations in older men. Design: The Health in Men Study is a community-representative prospective cohort investigation of 4263 men aged ≥ 70 years. Cross-sectional hormone data from 3645 men were analysed. Methods: Early morning sera were assayed for total testosterone, sex hormone binding globulin (SHBG) and LH. Free testosterone was calculated using the Vermeulen method. Results: Mean (± s.d.) serum total testosterone was 15.4 ± 5.6 nmol/l (444 ± 162 ng/dl), SHBG 42.4 ± 16.7 nmol/l and free testosterone 278 ± 96 pmol/l (8.01 ± 2.78 ng/dl). Total testosterone correlated with SHBG (Spearman’s r = 0.6, P < 0.0001). LH and SHBG increased with age (r = 0.2, P < 0.0001 for both). Instead of declining, total testosterone increased marginally (r = 0.04, P = 0.007) whilst free testosterone declined with age (r = −0.1, P < 0.0001). Free testosterone was inversely correlated with LH (r = −0.1, P < 0.0001). In multivariate analyses, increasing age, body mass index (BMI) and LH were associated with lower free testosterone. Conclusions: In men aged 70–89 years, modulation of androgen action may occur via an age-related increase in SHBG and reduction in free testosterone without a decline in total testosterone concentration. Increasing age, BMI and LH are independently associated with lower free testosterone. Further investigation would be required to assess the clinical consequences of low serum free testosterone, particularly in older men in whom total testosterone may be preserved.


Author(s):  
William D. Hopkins ◽  
Mary C. Mareno ◽  
Sarah J. Neal Webb ◽  
Steven J. Schapiro ◽  
Mary A. Raghanti ◽  
...  

2008 ◽  
Vol 159 (4) ◽  
pp. 459-468 ◽  
Author(s):  
B Lapauw ◽  
S Goemaere ◽  
H Zmierczak ◽  
I Van Pottelbergh ◽  
A Mahmoud ◽  
...  

ObjectiveThis study was designed to assess longitudinal changes in serum testosterone levels, explore relationships with aging, genetic-, health-, and lifestyle-related factors, and investigate predictors of changes in healthy elderly men.DesignPopulation-based, longitudinal, 4-year observational study in 221 community-dwelling men aged 71–86 years at baseline.MethodsHormone levels assessed by immunoassay, anthropometry, questionnaires on general health, and genetic polymorphisms. Predictors of changes in testosterone levels explored using linear mixed-effects modeling for longitudinal analyses.ResultsTotal testosterone (TT), free testosterone, and bioavailable testosterone (BioT) levels decreased with aging, decreases in BioT being most marked. No changes in sex hormone-binding globulin (SHBG) or estradiol (E2), while LH and FSH levels increased during follow-up. Subjects who gained weight displayed a greater decline in TT levels, mainly due to decreasing SHBG levels. However, baseline body composition was not predictive of subsequent changes in testosterone levels. Baseline E2 (P=0.023 to 0.004), LH (P=0.046 to 0.005), and FSH (P<0.002) levels were independently positively associated with a faster decline in testosterone fractions, although only FSH remained significant when adjusting for baseline testosterone (P=0.041–0.035). Carriers of a ‘TA’ haplotype of the estrogen receptor α gene (ERα) PvuII and XbaI polymorphisms displayed a slower decline of TT and BioT (P=0.041–0.007).ConclusionsIn elderly men with already low serum testosterone levels, a further decline was observed, independent of baseline age. The identification of FSH levels as a predictor of this decline appears to reflect the testicular mechanisms of aging-related changes in testosterone production, whereas associations with E2 and ERα polymorphisms are suggestive of estrogen-related processes, possibly related to changes in the neuroendocrine regulation of testosterone production.


2020 ◽  
Author(s):  
William D Hopkins ◽  
Mary Catherine Mareno ◽  
Sarah J Neal Webb ◽  
Steve J Schapiro ◽  
Mary Ann Raghanti ◽  
...  

AbstractChimpanzees are the species most closely related to humans yet age-related changes in brain and cognition remain poorly understood. The lack of studies on age-related changes in cognition in chimpanzees is particularly unfortunate in light of the recent evidence demonstrating that this species naturally develops Alzheimer’s disease (AD) neuropathology. Here, we tested 213 young, middle-aged, and elderly chimpanzees on the Primate Cognitive Test Battery (PCTB), a set of 13 tasks that assess physical and social cognition in nonhuman primates. A subset of these chimpanzees (n=146) were tested a second time on a portion of the PCTB tasks as a means of evaluating longitudinal changes in cognition. Cross-sectional analyses revealed a significant quadratic association between age and cognition with younger and older chimpanzees performing more poorly than middle-aged individuals. Longitudinal analyses showed that, while young chimpanzees’ performance improved from test 1 to test 2, middle-aged and elderly chimpanzees’ performance showed significant decline over time. The collective data show that chimpanzees, like other nonhuman primates, show age-related decline in cognition. Further investigations into whether the observed cognitive decline is associated with AD pathologies in chimpanzees would be invaluable in understanding the comparative biology of aging and neuropathology in primates.


2003 ◽  
Vol 149 (2) ◽  
pp. 145-152 ◽  
Author(s):  
J Svartberg ◽  
M Midtby ◽  
KH Bonaa ◽  
J Sundsfjord ◽  
RM Joakimsen ◽  
...  

OBJECTIVE: To study whether lifestyle factors and/or chronic disease are associated with the age-related decline of total and free testosterone in men, or if these factors might be associated with the variation of total and free testosterone but not with their age-related decline. DESIGN: A population-based, cross-sectional study was used. METHODS: Total testosterone and sex hormone binding globulin (SHBG) levels were analyzed and free testosterone levels were calculated in 1563 men participating in the Tromso study in 1994/1995. Anthropometric characteristics were also measured and two standardized questionnaires completed, including lifestyle factors and medical history. The data were analyzed with multiple linear regression analysis of covariance, and logistic regression. RESULTS: Total and free testosterone were inversely associated (P=0.001 and P<0.001), while SHBG was positively associated (P<0.001) with age. Body mass index (BMI) was inversely associated with total (P<0.001) and free (P=0.016) testosterone and SHBG (P<0.001). Both total and free testosterone were positively associated with tobacco consumption (P<0.001 and P=0.004) and total testosterone was positively associated with coffee consumption (P<0.001). SHBG was positively associated with smoking (P=0.004) and coffee consumption (P<0.001). Men who reported having had a stroke or having a cancer diagnosis had lower levels of total testosterone (P<0.001 and P<0.01) and free testosterone (P<0.01). CONCLUSIONS: BMI and smoking are independent contributors to the variation of total and free testosterone and SHBG levels, and coffee consumption to the variation of total testosterone and SHBG. Thus, lifestyle factors can have a direct effect on circulating levels of free endogenous sex hormones and to total levels due to the effect on SHBG levels.


2019 ◽  
Vol 105 (6) ◽  
pp. 1888-1898 ◽  
Author(s):  
André Madsen ◽  
Ninnie B Oehme ◽  
Mathieu Roelants ◽  
Ingvild S Bruserud ◽  
Geir Egil Eide ◽  
...  

Abstract Context Testicular growth represents the best clinical variable to evaluate male puberty, but current pediatric hormone references are based on chronological age and subjective assessments of discrete puberty development stages. Determination of testicular volume (TV) by ultrasound provides a novel approach to assess puberty progression and stratify hormone reference intervals. Objective The objective of this article is to establish references for serum testosterone and key hormones of the male pituitary-gonadal signaling pathway in relation to TV determined by ultrasound. Design, Setting, and Participants Blood samples from 414 healthy Norwegian boys between ages 6 and 16 years were included from the cross-sectional “Bergen Growth Study 2.” Participants underwent testicular ultrasound and clinical assessments, and serum samples were analyzed by liquid chromatography tandem–mass spectrometry and immunoassays. Main Outcome Measures We present references for circulating levels of total testosterone, luteinizing hormone, follicle-stimulating hormone, and sex hormone–binding globulin in relation to TV, chronological age, and Tanner pubic hair stages. Results In pubertal boys, TV accounted for more variance in serum testosterone levels than chronological age (Spearman r = 0.753, P &lt; .001 vs r = 0.692, P &lt; .001, respectively). Continuous centile references demonstrate the association between TV and hormone levels during puberty. Hormone reference intervals were stratified by TV during the pubertal transition. Conclusions Objective ultrasound assessments of TV and stratification of hormone references increase the diagnostic value of traditional references based on chronological age or subjective staging of male puberty.


2008 ◽  
Vol 158 (6) ◽  
pp. 785-792 ◽  
Author(s):  
S A Paul Chubb ◽  
Zoë Hyde ◽  
Osvaldo P Almeida ◽  
Leon Flicker ◽  
Paul E Norman ◽  
...  

BackgroundReduced circulating testosterone and sex hormone-binding globulin (SHBG) are implicated as risk factors for metabolic syndrome. As SHBG increases with age while testosterone declines, we examined the relative contributions of SHBG and testosterone to the risk of metabolic syndrome in older men.MethodsWe conducted a cross-sectional study of 2502 community-dwelling men aged ≥70 years without known diabetes. Metabolic syndrome was defined using the National Cholesterol Education Program-Third Adult Treatment Panel (NCEP-ATPIII) criteria. Early morning fasting sera were assayed for total testosterone, SHBG and LH. Free testosterone was calculated using mass action equations.ResultsThere were 602 men with metabolic syndrome (24.1%). The risk of metabolic syndrome increased for total testosterone <20 nmol/l, SHBG <50 nmol/l and free testosterone <300 pmol/l. In univariate analyses SHBG was associated with all five components of metabolic syndrome, total testosterone was associated with all except hypertension, and free testosterone was associated only with waist circumference and triglycerides. In multivariate analysis, both total testosterone and especially SHBG remained associated with metabolic syndrome, with odds ratios of 1.34 (95% confidence interval (CI): 1.18–1.52) and 1.77 (95% CI: 1.53–2.06) respectively. Men with hypogonadotrophic hypogonadism (total testosterone <8 nmol/l, LH ≤12 IU/l) had the highest prevalence of metabolic syndrome (53%,P<0.001).ConclusionsLower SHBG is more strongly associated with metabolic syndrome than lower total testosterone in community-dwelling older men. SHBG may be the primary driver of these relationships, possibly reflecting its relationship with insulin sensitivity. Further studies should examine whether measures that raise SHBG protect against the development of metabolic syndrome in older men.


Author(s):  
Fateheya M. Metwally ◽  
Asmaa M. Elfiky ◽  
Neven E. Sharaf ◽  
Hend Rashad

Abstract Objectives Di-2-ethylhexyl phthalate (DEHP) is ubiquitous, known as an endocrine disruptor. DEHP is a widespread prevalence in general and occupational populations which raised great public concerns due to its potentially harmful health effects on the male reproductive system. We aimed to assess occupational levels of DEHP on gonadotropin and gonadal hormones including luteinizing hormone (LH), follicle-stimulating hormone (FSH), total testosterone (TT), and sex hormone binding globulin (SHBG) and evaluate its potential effects on Asp327Asn polymorphisms SHBG gene. Methods We measured the levels of DEHP of 90 male workers in one of polyvinyl chloride (PVC) industry plant using enzyme-linked immunosorbent assay. Sex hormones were examined and Asp327Asn polymorphisms SHBG gene were detected by PCR-RFLP in all participants. Results The workers were divided into low- and high- DEHP exposed groups based on the geometric mean (GM) levels (183.86 U/L) in serum. TT and TT: LH ratio were negatively correlated to DEHP levels (r=−0.213, p=0.038), (r=−0.225, p=0.027), respectively. The linear regression analysis revealed that a 10-fold increase of serum DEHP was found to be associated with 2.07 fold decreased in TT and a 2.26 fold decreased in TT/LH ratio. Conclusions Serum testosterone is negatively associated with DEHP exposure in occupational workers.


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