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Yeap BB, Chubb SAP, McCaul KA, Ho KKY, Hankey GJ, Norman PE, Flicker L. Associations of IGF1 and IGFBPs 1 and 3 with all-cause and cardiovascular mortality in older men: the Health In Men Study. Eur J Endocrinol 2011; 164:715-23. [PMID: 21378090 DOI: 10.1530/eje-11-0059] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
OBJECTIVE Circulating IGF1 declines with age while ill-health increases. Controversy remains whether differences in the levels of IGF1 and its binding proteins 1 and 3 (IGFBP1 and IGFBP3) determine health outcomes during ageing. We examined associations of IGF1, IGFBP1 and IGFBP3 with all-cause and cardiovascular mortality in older men. DESIGN We conducted a prospective cohort study of community-dwelling men aged ≥70 years. METHODS Plasma collected at baseline (2001-2004) was assayed for total IGF1, IGFBP1 and IGFBP3. Incidence and causes of death from time of recruitment to 31 December 2008 were ascertained using the Western Australian Data Linkage System. Cox regression analyses were performed, adjusting for conventional cardiovascular risk factors. RESULTS Among 3983 men followed for 5.2 years (median), 694 deaths occurred, 243 from cardiovascular disease (CVD). There was no difference in survival according to quintiles of IGF1. Increased IGFBP1 predicted increased all-cause mortality (highest versus lowest quintile: adjusted hazard ratio (HR)=1.98, 95% confidence interval (CI)=1.52-2.57, P<0.001 for trend) and increased cardiovascular mortality (HR=3.42 (2.03-5.77), P<0.001 for trend). Decreased IGFBP3 predicted increased all-cause mortality (lowest versus highest quintile: HR=1.57, 95% CI=1.23-2.01, P=0.007 for trend). Associations of IGFBP1 and IGFBP3 with all-cause mortality were not attenuated by adjustment for IGF1 levels. CONCLUSIONS In older men, higher IGFBP1 and lower IGFBP3 levels predict overall and CVD-related mortality, while IGF1 levels are not associated with mortality. Further studies are needed to clarify the underlying mechanisms by which IGFBP1 and IGFBP3 levels are associated with mortality risk, and whether this occurs independently of IGF1.
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Hyde Z, Norman PE, Flicker L, Hankey GJ, McCaul KA, Almeida OP, Chubb SAP, Yeap BB. Elevated LH predicts ischaemic heart disease events in older men: the Health in Men Study. Eur J Endocrinol 2011; 164:569-77. [PMID: 21285084 DOI: 10.1530/eje-10-1063] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
CONTEXT Hypogonadism in men is associated with insulin resistance, elevations in pro-inflammatory cytokines and fibrinogen, and an atherogenic lipid profile. However, it is uncertain whether the age-related decline in testosterone is associated with ischaemic heart disease (IHD) events. OBJECTIVE To determine whether testosterone and its associated hormones, sex hormone-binding globulin (SHBG) and LH, predict IHD events in older men. DESIGN Prospective cohort study. METHODS Between 2001 and 2004, 3637 community-dwelling men aged 70-88 years underwent a clinical assessment of cardiovascular risk factors and biochemical assessment of testosterone, SHBG and LH. Free testosterone was calculated using mass action equations. Participants were followed until December 2008 using electronic record linkage to capture IHD events (hospital admission or death). RESULTS Mean follow-up was 5.1 years. During this period, 618 men (17.0%; 95% confidence interval (CI) 15.8, 18.3%) experienced an event, of which 160 were fatal. Men with higher baseline total or free testosterone levels experienced fewer IHD events (hazard ratio (HR)=0.89; 95% CI 0.82, 0.97 and HR=0.86; 95% CI 0.79, 0.94 for each one s.d. increase in total and free testosterone respectively). These associations were maintained after adjustment for age and waist:hip ratio but did not persist after adjustment for prevalent IHD or other cardiovascular risk factors. SHBG was not associated with IHD events. In contrast, higher LH levels were associated with reduced event-free survival in both univariate (HR=1.15; 95% CI 1.08, 1.22) and adjusted analyses (HR=1.08; 95% CI 1.01, 1.15). CONCLUSIONS Dysregulation of the hypothalamic-pituitary-gonadal axis may be a risk factor for IHD. Further studies of men with either elevated LH or low testosterone are warranted.
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Power BD, Alfonso H, Flicker L, Hankey GJ, Yeap BB, Almeida OP. Body adiposity in later life and the incidence of dementia: the health in men study. PLoS One 2011; 6:e17902. [PMID: 21464984 PMCID: PMC3064574 DOI: 10.1371/journal.pone.0017902] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Accepted: 02/14/2011] [Indexed: 12/02/2022] Open
Abstract
Objective To determine if adiposity in later life increases dementia hazard. Methods Cohort study of 12,047 men aged 65–84 years living in Perth, Australia. Adiposity exposures were baseline body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR). We used the Western Australian Data Linkage System (WADLS) to establish the presence of new cases of dementia between 1996 and 2009 according to the International Classification of Diseases (ICD). Crude and adjusted hazard ratio (HR, 95% confidence interval, 95%CI) of dementia for each adiposity marker was calculated using Cox regression models. Other measured factors included age, marital status, education, alcohol use, smoking, diet, physical activity, and prevalent hypertension, diabetes, dyslipidaemia and cardiovascular disease. Results Compared with men with BMI<25, participants with BMI between 25–30 had lower adjusted HR of dementia (HR = 0.82, 95% CI = 0.70–0.95). The HR of dementia for men with BMI≥30 was comparable to men with BMI<25 (HR = 0.82, 95%CI = 0.67–1.01). Waist circumference showed no obvious association with dementia hazard. Men with WHR≥0.9 had lower adjusted HR of dementia than men with WHR <0.9 (HR = 0.82, 95%CI = 0.69–0.98). We found a “J” shape association between measures of obesity and the hazard of dementia, with the nadir of risk being in the overweight range of BMI and about 1 for WHR. Conclusions Higher adiposity is not associated with incident dementia in this Australian cohort of older men. Overweight men and those with WHR≥0.9 have lower hazard of dementia than men with normal weight and with WHR<0.9.
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Abstract
Impaired glucose metabolism is common and contributes to the risk of diabetes and cardiovascular disease. Deletion of the gene for the osteoblast-derived protein, osteocalcin, leads to insulin resistance in mice, while the addition of osteocalcin increases insulin secretion from β-cells and adiponectin expression in adipocytes. Osteocalcin deficiency in γ-carboxyl groups, undercarboxylated osteocalcin, was found to improve insulin secretion and sensitivity in experiments. Recent studies have examined the relevance of these findings to glucose metabolism and cardiovascular risk in humans. Low total osteocalcin levels are associated with insulin resistance, diabetes and metabolic syndrome in observational studies. New therapeutic approaches to diabetes and heart disease may be anticipated if this bone-derived protein is involved in the regulation of glucose metabolism and cardiovascular risk.
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Wong BXW, Kyle RA, Croft KD, Quinn CM, Jessup W, Yeap BB. Modulation of macrophage fatty acid content and composition by exposure to dyslipidemic serum in vitro. Lipids 2011; 46:371-80. [PMID: 21286835 DOI: 10.1007/s11745-011-3528-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Accepted: 11/14/2010] [Indexed: 10/18/2022]
Abstract
Macrophages in arterial walls accumulate lipids leading to the development of atherosclerotic plaques. However, mechanisms underlying macrophage lipid accumulation and foam cell formation are often studied without accounting for risk factors such as dyslipidemia. We investigated the effect of varying concentrations of triglyceride (TG) within physiological range on macrophage fatty acid (FA) accumulation and expression of cholesterol efflux proteins. Human monocytes were cultured in media supplemented with 10% sera containing low (0.7 mmol/L) to high (1.4 mmol/L) TG. The resulting macrophages were harvested after 10 days for analysis of FA content and composition and expression of genes involved in lipid metabolism. Exposure to higher TG and lower HDL concentrations in media increased macrophage lipid content. Macrophages exposed to higher TG had increased total FA content compared with controls (876 μg/mg protein vs. 652 μg/mg protein) and greater proportions of C16:0, C18:1 and C18:2. Macrophage expression of both ABCA1 and ABCG1 cholesterol efflux proteins were reduced when higher TG concentrations were present in the media. Expression of scavenger receptor CD36, involved in lipoprotein uptake, was also downregulated in macrophages exposed to higher TG. Culturing macrophages in conditions of higher versus lower TG influenced macrophage FA content and composition, and levels of regulatory proteins. Replicating in vitro levels of dyslipidemia encountered in vivo may provide an informative model for investigation of atherogenesis.
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Hyde Z, Flicker L, Hankey GJ, Almeida OP, McCaul KA, Chubb SAP, Yeap BB. Prevalence of sexual activity and associated factors in men aged 75 to 95 years: a cohort study. Ann Intern Med 2010; 153:693-702. [PMID: 21135292 DOI: 10.7326/0003-4819-153-11-201012070-00002] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Knowledge about sexuality in elderly persons is limited, and normative data are lacking. OBJECTIVE To determine the proportion of older men who are sexually active and to explore factors predictive of sexual activity. DESIGN Population-based cohort study. SETTING Community-dwelling men from Perth, Western Australia, Australia. PARTICIPANTS 3274 men aged 75 to 95 years. MEASUREMENTS Questionnaires from 1996 to 1999, 2001 to 2004, and 2008 to 2009 assessed social and medical factors. Sex hormones were measured from 2001 to 2004. Sexual activity was assessed by questionnaire from 2008 to 2009. RESULTS A total of 2783 men (85.0%) provided data on sexual activity. Sex was considered at least somewhat important by 48.8% (95% CI, 47.0% to 50.6%), and 30.8% (CI, 29.1% to 32.5%) had had at least 1 sexual encounter in the past 12 months. Of the latter, 56.5% were satisfied with the frequency of activity, whereas 43.0% had sex less often than preferred. In cross-sectional analyses, increasing age, partner's lack of interest, partner's physical limitations, osteoporosis, prostate cancer, diabetes, antidepressant use, and β-blocker use were independently associated with reduced odds of sexual activity. Living with a partner and having a non-English-speaking background were associated with increased odds. In longitudinal analyses, higher testosterone levels were associated with increased odds of being sexually active. Other factors were similar to the cross-sectional model. LIMITATIONS Response bias may have influenced findings because sexuality can be a sensitive topic. Attrition may have resulted in a healthier-than-average sample of older men. CONCLUSION One half of elderly men consider sex important, and one third report being sexually active. Men's health problems were associated with lack of sexual activity. Key modifiable risk factors include diabetes, depression, and medication use. Endogenous testosterone levels predict sexual activity, but the role of testosterone therapy remains uncertain. PRIMARY FUNDING SOURCE National Health and Medical Research Council of Australia.
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Yeap BB, Beilin J, Shi Z, Knuiman MW, Olynyk JK, Chubb SAP, Bruce DG, Milward EA. The C282Y polymorphism of the hereditary hemochromatosis gene is associated with increased sex hormone-binding globulin and normal testosterone levels in men. J Endocrinol Invest 2010; 33:544-8. [PMID: 20160468 DOI: 10.1007/bf03346645] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Hereditary hemochromatosis resulting either from homozygosity for the C282Y polymorphism of the HFE gene, or compound heterozygosity for C282Y and H63D, manifests with liver disease and hypogonadism. However, it is unclear whether men who are heterozygotes for C282Y or H63D exhibit subtle abnormalities of sex hormone status. AIMS To evaluate whether heterozygosity for either of the HFE gene polymorphisms C282Y or H63D is associated with circulating testosterone and SHBG in men. SUBJECTS AND METHODS We performed a cross-sectional analysis of 388 community-dwelling men. Men were genotyped for C282Y and H63D. Sera were analysed for testosterone and SHBG, and insulin resistance was estimated using a homeostatic model (HOMA2-IR). RESULTS Mean age of men in the cohort was 56.9 yr. Men who were heterozygous for the C282Y polymorphism in the HFE gene had higher SHBG levels than men who did not carry this polymorphism (mean ± SE, 38.2 ± 1.64 vs 32.8 ± 0.71 nmol/l, p=0.006). Total and free testosterone levels did not differ in the two groups. In multivariate analysis adjusting for potential confounders including age, waist circumference, testosterone, and HOMA2-IR, C282Y heterozygosity remained associated with SHBG levels (p<0.001). CONCLUSION The C282Y polymorphism is associated with SHBG levels in men who do not manifest iron overload. Further studies are needed to clarify potential mechanisms and determine the clinical relevance of this finding.
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Yeap BB, Chubb SAP, Flicker L, McCaul KA, Ebeling PR, Beilby JP, Norman PE. Reduced serum total osteocalcin is associated with metabolic syndrome in older men via waist circumference, hyperglycemia, and triglyceride levels. Eur J Endocrinol 2010; 163:265-72. [PMID: 20501596 DOI: 10.1530/eje-10-0414] [Citation(s) in RCA: 130] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Bone-derived undercarboxylated osteocalcin regulates insulin secretion and sensitivity in mice, and reduced serum total osteocalcin (TOC) is associated with diabetes in humans. However, the relationship between TOC levels and other cardiovascular risk factors is uncertain. We sought to determine whether serum TOC is associated with metabolic syndrome and its components in older men. DESIGN Cross-sectional analysis from a population-based cohort of men aged >or=70 years. METHODS Early morning sera were assayed for TOC. Insulin resistance was estimated using a homeostatic model (HOMA2-IR). Metabolic syndrome was defined according to NCEP-ATPIII criteria. RESULTS TOC was assayed in 4047 men. Men who were not fasting and reported having bone fractures, Paget's disease, or bisphosphonate, glucocorticoid, or warfarin use were excluded, leaving 2765 men with metabolic syndrome present in 797 (28.8%). TOC was inversely associated with waist circumference, glucose, and triglyceride levels and HOMA2-IR (all P<0.001), and was lower in men with metabolic syndrome (mean+/-S.E.M.: 20.1+/-0.4 vs 21.4+/-0.2 microg/l, P=0.002). In multivariate analysis, men with TOC of 13.25-16.55 and <13.25 microg/l had 1.5- to 2-fold increased risk of metabolic syndrome compared with men with levels >or=30 microg/l. TOC remained associated with metabolic syndrome after adjustment for individual components, but not after adjusting for both waist circumference and glucose. CONCLUSIONS Increased waist circumference, reduced TOC, elevated glucose, and triglyceride levels are inter-related in aging men. Osteocalcin may lie in the causal pathway between central adiposity and insulin resistance. Further research is required to evaluate whether interventions which raise osteocalcin levels might decrease cardiovascular risk.
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Hyde Z, Flicker L, Almeida OP, Hankey GJ, McCaul KA, Chubb SAP, Yeap BB. Low free testosterone predicts frailty in older men: the health in men study. J Clin Endocrinol Metab 2010; 95:3165-72. [PMID: 20410223 DOI: 10.1210/jc.2009-2754] [Citation(s) in RCA: 208] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
CONTEXT The prevalence of frailty increases, whereas testosterone decreases, as men age. Low testosterone may be a risk factor for development of this syndrome. OBJECTIVE Our objective was to determine whether testosterone levels are associated with frailty. DESIGN We conducted a prospective cohort study. SETTING AND PARTICIPANTS Between 2001 and 2004, frailty was assessed in 3616 community-dwelling men aged 70-88 yr. Frailty was reassessed in 1586 men aged 76-93 yr in 2008-2009. MAIN OUTCOME MEASURES Frailty was assessed with the FRAIL scale, comprising five domains: fatigue, difficulty climbing a flight of stairs, difficulty walking more than 100 m, more than five illnesses present, or weight loss greater than 5%. Testosterone, SHBG, and LH were assayed at baseline. Free testosterone was calculated using mass action equations. RESULTS At baseline, 15.2% of men (n = 548) were frail (at least three deficits), increasing to 23.0% (n = 364) at follow-up. At baseline, each 1 sd decrease in total or free testosterone level was associated with increased odds of frailty [odds ratio (OR) = 1.23; 95% confidence interval (CI) = 1.11-1.38, and OR = 1.29; 95% CI = 1.15-1.44 for total and free testosterone, respectively]. Lower LH was associated with reduced odds of frailty (OR = 0.88; 95% CI = 0.81-0.95). Adjustments were made for age, body mass index, smoking, diabetes, social support, and other covariates. At follow-up, only lower free testosterone levels (OR = 1.22; 95% CI = 1.05-1.42) predicted frailty. CONCLUSIONS Lower free testosterone was independently associated with frailty at baseline and follow-up. Randomized trials should explore whether testosterone therapy can prevent the development of frailty.
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Abstract
PURPOSE OF REVIEW There is increasing interest in age-related changes in sex hormone levels as a potentially treatable cause of ill-health in men. Relationships between androgens and cardiovascular disease will be discussed, with particular attention to more recently published research. RECENT FINDINGS In middle-aged and older men, lower testosterone levels are associated with insulin resistance, metabolic syndrome and diabetes, interrelated conditions that predispose to cardiovascular disease. The relationship between androgens and preclinical atherosclerosis requires confirmation. Nevertheless, lower testosterone levels predict cardiovascular events, such as stroke and transient ischaemic attack, in older men and are associated with higher cardiovascular and overall mortality. Testosterone is aromatized to oestradiol, and both higher and lower oestradiol levels have been associated with cardiovascular risk. Randomized trials have shown that testosterone supplementation in men with existing coronary artery disease can be protective against myocardial ischaemia. However, additional interventional studies are needed with endpoints of cardiovascular events. SUMMARY Observational studies continue to relate reduced circulating testosterone to cardiovascular risk, atherosclerosis and mortality in men. The role of oestradiol as a marker for cardiovascular disease requires clarification. Larger randomized trials are needed to establish whether hormonal therapy would reduce the burden of cardiovascular disease in ageing men.
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Yeap BB, Hyde Z, Norman PE, Chubb SAP, Golledge J. Associations of total testosterone, sex hormone-binding globulin, calculated free testosterone, and luteinizing hormone with prevalence of abdominal aortic aneurysm in older men. J Clin Endocrinol Metab 2010; 95:1123-30. [PMID: 20061425 DOI: 10.1210/jc.2009-1696] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
CONTEXT Abdominal aortic aneurysm (AAA) is associated with mortality in older adults, and increasing aortic diameter predicts incident cardiovascular events. Although AAA occurs predominantly in men, its association with male sex hormones is unclear. OBJECTIVE The objective of the study was to examine whether male sex hormones are independently associated with AAA or increased abdominal aortic diameter. DESIGN This was a cross-sectional analysis. SETTING AND PARTICIPANTS Participants included 3620 community-dwelling men aged 70-88 yr. MAIN OUTCOME MEASURES Abdominal aortic diameter was measured with ultrasound. Early morning sera were assayed for total testosterone, SHBG, and LH. Free testosterone was calculated using mass action equations. RESULTS AAA (aortic diameter > or =30 mm) was present in 262 men (7.2%). Men with AAA had lower serum total and free testosterone (mean +/- sd 14.5 +/- 6.0 vs. 15.5 +/- 5.6 nmol/liter, P = 0.005 and 256 +/- 87 vs. 280 +/- 97 pmol/liter, P < 0.001, respectively) compared with men without. LH was higher in men with AAA (median, interquartile range: 4.9, 3.1-7.9 vs. 4.3, 3.0-6.4 IU/liter, P = 0.013). In multivariate analysis adjusting for potential confounders, free testosterone was negatively associated with AAA (odds ratio per 1 sd increase: 0.84, 95% confidence interval 0.72-0.98, P = 0.026). LH was positively associated (odds ratio 1.14, 95% confidence interval 1.03-1.25, P = 0.008). Comparable results were seen with aortic diameter analyzed as a continuous variable. CONCLUSIONS Lower free testosterone and higher LH levels are independently associated with AAA in older men. Impaired gonadal function may be involved in arterial dilatation as well as occlusive vascular disease in older men. Additional studies are needed to clarify direction of causality and determine possible scope for preventive intervention.
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Yeap BB, Chubb SAP, Ho KKY, Setoh JWS, McCaul KA, Norman PE, Jamrozik K, Flicker L. IGF1 and its binding proteins 3 and 1 are differentially associated with metabolic syndrome in older men. Eur J Endocrinol 2010; 162:249-57. [PMID: 19917654 DOI: 10.1530/eje-09-0852] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Circulating IGF1 declines with age, and reduced circulating IGF1 is associated with increased cardiovascular mortality in some but not all studies. The relationship between IGF-binding proteins 3 and 1 (IGFBP3 and IGFBP1) with risk of cardiovascular disease remains unclear. We sought to examine associations between IGF1, IGFBP3 and IGFBP1 with metabolic syndrome in older men. DESIGN Cross-sectional analysis of 3980 community-dwelling men aged >or=70 years. Methods Morning plasma levels of IGF1, IGFBP3 and IGFBP1 were assayed. Metabolic syndrome was defined according to National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATPIII) criteria. RESULTS For IGF1 and IGFBP3, there was a U-shaped relationship, with middle quintiles possessing the lowest odds ratios (OR) for metabolic syndrome (reference Q1, Q3 IGF1: OR 0.74, 95% confidence intervals 0.57-0.96, Q3 IGFBP3: OR 0.67, 0.51-0.87). Increasing IGFBP1 was associated with reduced risk of metabolic syndrome with a dose-response gradient (reference Q1, OR for Q2 to Q5 IGFBP1: 0.56, 0.33, 0.22 and 0.12 respectively, P<0.001). IGF1 was associated with two, IGFBP1 with four and IGFBP3 with all five components of the metabolic syndrome. The ratio of IGF1/IGFBP3 was not associated with metabolic syndrome. CONCLUSIONS In older men, both lower and higher IGF1 and IGFBP3 levels may be metabolically unfavourable. IGFBP1, as a marker of insulin sensitivity, is relevant in the assessment of metabolic syndrome, while the IGF1/IGFBP3 ratio is less informative. Longitudinal follow-up of this cohort would be needed to determine whether these distributions of IGF1, IGFBP3 and IGFBP1 predict incidence of cardiovascular events during male ageing.
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Hyde Z, Flicker L, Almeida OP, McCaul KA, Jamrozik K, Hankey GJ, Chubb SP, Yeap BB. Higher Luteinizing Hormone is Associated with Poor Memory Recall: The Health in Men Study. ACTA ACUST UNITED AC 2010; 19:943-51. [DOI: 10.3233/jad-2010-1342] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Yeap BB, Chubb SAP, Hyde Z, Jamrozik K, Hankey GJ, Flicker L, Norman PE. Lower serum testosterone is independently associated with insulin resistance in non-diabetic older men: the Health In Men Study. Eur J Endocrinol 2009; 161:591-8. [PMID: 19661128 DOI: 10.1530/eje-09-0348] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Insulin resistance is associated with metabolic syndrome and type 2 diabetes, representing a risk factor for cardiovascular disease. This relationship may be modulated to some extent by age-related changes in sex hormone status. We examined whether lower testosterone or sex hormone-binding globulin (SHBG) levels in older men are associated with insulin resistance independently of measures of central obesity. DESIGN Cross-sectional analysis of 2470 community-dwelling non-diabetic men aged > or = 70 years. METHODS Age, body mass index (BMI) and waist circumference were measured. Early morning sera were assayed for total testosterone, SHBG, LH and insulin levels. Free testosterone was calculated using mass action equations, and insulin resistance was assessed using a homeostatic model (HOMA2-IR). RESULTS Total testosterone, free testosterone and SHBG declined progressively across increasing quintiles of HOMA2-IR (all P<0.001) and correlated inversely with log HOMA2-IR (r=-0.27, -0.14 and -0.24 respectively, all P<0.001). After adjusting for age, BMI, waist circumference, high-density lipoprotein and triglyceride levels, total testosterone was independently associated with log HOMA2-IR (beta=0.05, P<0.001), while SHBG was not. Serum total testosterone <8 nmol/l was associated with HOMA2-IR in the highest quintile (odds ratio (OR) 1.67, 95% confidence interval (CI) 1.02-2.73) as was total testosterone > or = 8 and <15 nmol/l (OR 1.29, 95% CI 1.03-1.63). CONCLUSIONS In older men, lower total testosterone is associated with insulin resistance independently of measures of central obesity. This association is seen with testosterone levels in the low to normal range. Further studies are needed to evaluate interventions that raise testosterone levels in men with reduced insulin sensitivity.
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Thong KY, Fegan PG, Yeap BB. Glycaemic control in patients with type 1 diabetes after provision of public hospital‐funded insulin pumps. Med J Aust 2009. [DOI: 10.5694/j.1326-5377.2009.tb02794.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Yeap BB. Testosterone and growth hormone in older men: for better or for worse? Expert Rev Endocrinol Metab 2009; 4:321-323. [PMID: 30781278 DOI: 10.1586/eem.09.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Evaluation of: Sattler FR, Castaneda-Sceppa C, Binder EF et al. Testosterone and growth hormone improve body composition and muscle performance in older men. J. Clin. Endocrinol. Metab. 94(6), 1991-2001 (2009). In men, testosterone and IGF1 levels decline with increasing age, and lower levels of these hormones are associated with poorer health. A recent, randomized clinical trial demonstrates the additive effects of testosterone and growth hormone supplementation to increase lean body mass, reduce fat mass and improve muscle strength in older men. These findings highlight the interaction between these two hormones and provide a model for further evaluation of combined therapy to explore other end points, such as cardiovascular risk.
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Yeap BB, Hyde Z, Almeida OP, Norman PE, Chubb SAP, Jamrozik K, Flicker L, Hankey GJ. Lower testosterone levels predict incident stroke and transient ischemic attack in older men. J Clin Endocrinol Metab 2009; 94:2353-9. [PMID: 19351733 DOI: 10.1210/jc.2008-2416] [Citation(s) in RCA: 180] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
CONTEXT Lower circulating testosterone concentrations are associated with metabolic syndrome, type 2 diabetes, carotid intima-media thickness, and aortic and lower limb arterial disease in men. However, it is unclear whether lower testosterone levels predict major cardiovascular events. OBJECTIVE We examined whether lower serum testosterone was an independently significant risk factor for symptomatic cerebrovascular events in older men. DESIGN This was a prospective observational study with median follow-up of 3.5 yr. SETTING Community-dwelling, stroke-free older men were studied. PARTICIPANTS A total of 3443 men at least 70 yr of age participated in the study. MAIN OUTCOME MEASURES Baseline serum total testosterone, SHBG, and LH were assayed. Free testosterone was calculated using mass action equations. Incident stroke or transient ischemic attack (TIA) was recorded. RESULTS A first stroke or TIA occurred in 119 men (3.5%). Total and free testosterone concentrations in the lowest quartiles (<11.7 nmol/liter and <222 pmol/liter) were associated with reduced event-free survival (P = 0.014 and P = 0.01, respectively). After adjustment including age, waist-hip ratio, waist circumference, smoking, hypertension, dyslipidemia, and medical comorbidity, lower total testosterone predicted increased incidence of stroke or TIA (hazard ratio = 1.99; 95% confidence interval, 1.33-2.99). Lower free testosterone was also associated (hazard ratio = 1.69; 95% confidence interval, 1.15-2.48), whereas SHBG and LH were not independently associated with incident stroke or TIA. CONCLUSIONS In older men, lower total testosterone levels predict increased incidence of stroke or TIA after adjusting for conventional risk factors for cardiovascular disease. Men with low-normal testosterone levels had increased risk. Further studies are warranted to determine whether interventions that raise circulating testosterone levels might prevent cerebrovascular disease in men.
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Yeap BB, Almeida OP, Hyde Z, Norman PE, Chubb SAP, Jamrozik K, Hankey GJ, Flicker L. Healthier lifestyle predicts higher circulating testosterone in older men: the Health In Men Study. Clin Endocrinol (Oxf) 2009; 70:455-63. [PMID: 18691270 DOI: 10.1111/j.1365-2265.2008.03372.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Circulating testosterone declines during male ageing, and low testosterone may predispose to ill health. We sought to determine whether greater participation in healthy behaviours predicted reduced risk of subsequent lower circulating testosterone in older men. DESIGN Cross-sectional analysis of a population-based follow-up study. PARTICIPANTS A total of 3453 men aged 65-83 years. MEASUREMENTS Lifestyle score, a tally of eight prudent health-related behaviours, was determined during 1996-99. Early morning sera collected in 2001-04 were assayed for total testosterone, SHBG and LH. Free testosterone was calculated using mass action equations. RESULTS Mean (+/- SD) time between collection of lifestyle data and blood sampling was 5.7 +/- 0.9 years. Lifestyle score correlated with subsequent total testosterone (r = 0.06, P < 0.001) and SHBG (r = 0.07, P < 0.001), but not free testosterone (r = 0.03, P = 0.08) or LH (r = -0.03, P = 0.12). In multivariate analyses, higher lifestyle scores (4 and above) predicted reduced risk of total testosterone and SHBG in the lowest quartile of values. For the highest category (>or= 7), odds ratio (95% CI) for total testosterone and SHBG in the lowest quartile were 0.37 (0.18-0.77) and 0.26 (0.13-0.54), respectively. Lower lifestyle scores including and excluding body mass index predicted higher risk of total testosterone and SHBG in the lowest quartiles. CONCLUSIONS In men > 65 years old, higher lifestyle score reflecting greater engagement in healthy behaviours predicts higher subsequent total testosterone and SHBG levels. This relationship appears cumulative and may reflect interaction between lifestyle and insulin sensitivity. Successfully promoting healthy behaviours in older men could ameliorate the age-related decline in circulating testosterone.
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Yeap BB. Controversies in type 2 diabetes - An update. AUSTRALIAN FAMILY PHYSICIAN 2009; 38:22-25. [PMID: 19283231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
BACKGROUND Controversy has emerged concerning the risks associated with glitazone therapy in type 2 diabetes, specifically bone fracture and myocardial infarction. Results from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study have stimulated debate about appropriate glycated haemoglobin (HbA1c) targets. OBJECTIVE This article examines the context for glitazone therapy in patients with type 2 diabetes, the risks associated with pioglitazone and rosiglitazone, and arguments for targeting HbA1c at the threshold of 7%. DISCUSSION Pioglitazone and rosiglitazone can be employed as oral therapy in patients with type 2 diabetes and preserved endogenous insulin secretion. Potential benefits and risks of each agent should be considered. An acceptable initial target for HbA1c is 7%. Lowering HbA1c to 6.5% did not reduce macrovascular complications in patients with type 2 diabetes, but did reduce new or worsening nephropathy. Aggressive therapy aiming to lower HbA1c to <6% in patients with type 2 diabetes at especially high risk of cardiovascular disease may lead to a higher risk of mortality.
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Yeap BB, Beilin J, Shi Z, Knuiman MW, Olynyk JK, Bruce DG, Milward EA. Serum testosterone levels correlate with haemoglobin in middle-aged and older men. Intern Med J 2008; 39:532-8. [PMID: 19220545 DOI: 10.1111/j.1445-5994.2008.01789.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Lower testosterone levels are associated with anaemia in older men and women. The relation between testosterone and haemoglobin (Hb) in younger and middle-aged men is less well defined. The aim of the study was to examine the association between testosterone and Hb levels in men spanning middle to older ages. METHODS A cross-sectional analysis of 492 men aged 30.7-94.5 years from the Busselton Health Survey, Western Australia, was carried out. Haemoglobin (Hb), early-morning serum total testosterone and sex hormone-binding globulin (SHBG) were measured. Free testosterone was calculated using mass action equations. RESULTS Haemoglobin correlated to total and free testosterone concentrations (r= 0.13, P= 0.003 and r= 0.20, P < 0.001, respectively). Hb and SHBG were inversely correlated (r=-0.14, P= 0.001). Hb increased across lowest to highest quartiles of total testosterone (P= 0.02) and free testosterone (P < 0.001), but not SHBG. After adjusting for age, waist circumference, smoking status, alcohol consumption, renal function and ferritin, total testosterone was associated with Hb (beta= 0.037, P= 0.003) as was free testosterone (beta= 2.32, P < 0.001), whereas SHBG was not associated. CONCLUSION Testosterone concentration modulates Hb levels in community-dwelling men across a wide age range. Further studies are needed to clarify implications of this association between testosterone and Hb in men.
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Myhill PC, Sillars BA, Starkstein S, Annus T, Yeap BB. Reduction in salivary cortisol concentration correlates with resolution of psychosis in Cushing's syndrome. J Neuropsychiatry Clin Neurosci 2008; 20:113-5. [PMID: 18305301 DOI: 10.1176/jnp.2008.20.1.113] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Verdile G, Yeap BB, Clarnette RM, Dhaliwal S, Burkhardt MS, Chubb SP, De Ruyck K, Rodrigues M, Mehta PD, Foster JK, Bruce DG, Martins RN. Luteinizing Hormone Levels Are Positively Correlated with Plasma Amyloid-β Protein Levels in Elderly Men. ACTA ACUST UNITED AC 2008; 14:201-8. [DOI: 10.3233/jad-2008-14208] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Chubb SAP, Hyde Z, Almeida OP, Flicker L, Norman PE, Jamrozik K, Hankey GJ, Yeap BB. Lower sex hormone-binding globulin is more strongly associated with metabolic syndrome than lower total testosterone in older men: the Health in Men Study. Eur J Endocrinol 2008; 158:785-92. [PMID: 18505902 DOI: 10.1530/eje-07-0893] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Reduced 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. METHODS We conducted a cross-sectional study of 2502 community-dwelling men aged > or = 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. RESULTS There 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 < or = 12 IU/l) had the highest prevalence of metabolic syndrome (53%, P<0.001). CONCLUSIONS Lower 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.
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Almeida OP, Yeap BB, Hankey GJ, Jamrozik K, Flicker L. Low free testosterone concentration as a potentially treatable cause of depressive symptoms in older men. ACTA ACUST UNITED AC 2008; 65:283-9. [PMID: 18316674 DOI: 10.1001/archgenpsychiatry.2007.33] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Serum concentrations of gonadal hormones have been associated with various measures of well-being, but it is unclear whether their association with mood is confounded by concurrent physical morbidity. OBJECTIVE To determine whether the association between serum testosterone concentration and mood in older men is independent of physical comorbidity. DESIGN Cross-sectional study. SETTING Community of Perth, Western Australia. PARTICIPANTS A community sample of men aged 71 to 89 years. MAIN OUTCOME MEASURES We used the 15-item Geriatric Depression Scale (GDS-15) to assess depressed mood. Clinically significant depression was defined a priori as a GDS-15 score of 7 or greater. Physical health was assessed using the weighted Charlson index and the Physical Component Summary score of the 36-Item Short Form Health Survey. RESULTS Of 3987 men included in the study, 203 (5.1%; 95% confidence interval [CI], 4.4%-5.8%) had depression. Participants with depression had significantly lower total and free testosterone concentrations than nondepressed men (P < .001 for both). However, they were also more likely to smoke and to have low educational attainment, a body mass index categorized as obese, a Mini-Mental State Examination score less than 24, a history of antidepressant drug treatment, and greater concurrent physical morbidity. After adjusting for these factors and for age, men with depression were 1.55 (95% CI, 0.91-2.63) and 2.71 (95% CI, 1.49-4.93) times more likely to have total and free testosterone concentrations, respectively, in the lowest quintile. CONCLUSIONS A free testosterone concentration in the lowest quintile is associated with a higher prevalence of depression, and this association cannot be adequately explained by physical comorbidity. A randomized controlled trial is required to determine whether the link between low free testosterone level and depression is causal because older men with depression may benefit from systematic screening of free testosterone concentration and testosterone supplementation.
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Davis TME, Yeap BB, Davis WA, Bruce DG. Lipid-lowering therapy and peripheral sensory neuropathy in type 2 diabetes: the Fremantle Diabetes Study. Diabetologia 2008; 51:562-6. [PMID: 18193189 DOI: 10.1007/s00125-007-0919-2] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2007] [Accepted: 12/12/2007] [Indexed: 10/22/2022]
Abstract
AIMS/HYPOTHESIS The aim of this study was to assess the relationships between lipid-lowering therapy and the prevalence and incidence of peripheral sensory neuropathy in type 2 diabetes mellitus. METHODS We analysed data from an observational cohort study, the Fremantle Diabetes Study (FDS), specifically, (1) a cross-sectional sample comprising 1,237 FDS participants with type 2 diabetes mellitus, and (2) a longitudinal subgroup of 531 individuals who had attended six consecutive annual assessments. Neuropathy was identified using the clinical portion of the Michigan Neuropathy Screening Instrument. RESULTS At entry, the cross-sectional sample had a mean +/- SD age of 63.8+/-11.3 years, 48.7% were men, median (interquartile range) diabetes duration was 4.0 (1.0-9.0) years, and 30.9% had peripheral neuropathy. Fibrates and statins were used by 3.5 and 6.8%, respectively. Multiple logistic regression analysis showed that older age, longer diabetes duration, central adiposity, increased height, higher fasting serum glucose, albuminuria and aboriginality were significant independent positive predictors of prevalent neuropathy, while systolic blood pressure and fibrate use (odds ratio 0.30, 95% CI 0.10-0.86; p=0.025) were negatively associated. In the longitudinal subgroup, fibrate and statin use increased to 10.4 and 36.5%, respectively, over 5 years. In time-dependent Cox proportional hazards modelling, fibrate use [hazard ratio (HR) 0.52, 95% CI 0.27-0.98] and statin use (HR 0.65, 95% CI 0.46-0.93) were significant determinants of incident neuropathy (p <or= 0.042). CONCLUSIONS/INTERPRETATION These preliminary observational data suggest that therapy with a statin or a fibrate may protect against the development of diabetic peripheral sensory neuropathy, but there is a need for additional confirmatory evidence, preferably from randomised clinical trials.
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