Associations of Testosterone and Related Hormones With All-Cause and Cardiovascular Mortality and Incident Cardiovascular Disease in Men : Individual Participant Data Meta-analyses.

BACKGROUND: Whether circulating sex hormones modulate mortality and cardiovascular disease (CVD) risk in aging men is controversial. PURPOSE: To clarify associations of sex hormones with these outcomes. DATA SOURCES: Systematic literature review to July 2019, with bridge searches to March 2024. STUDY SELECTION: Prospective cohort studies of community-dwelling men with sex steroids measured using mass spectrometry and at least 5 years of follow-up. DATA EXTRACTION: Independent variables were testosterone, sex hormone-binding globulin (SHBG), luteinizing hormone (LH), dihydrotestosterone (DHT), and estradiol concentrations. Primary outcomes were all-cause mortality, CVD death, and incident CVD events. Covariates included age, body mass index, marital status, alcohol consumption, smoking, physical activity, hypertension, diabetes, creatinine concentration, ratio of total to high-density lipoprotein cholesterol, and lipid medication use. DATA SYNTHESIS: Nine studies provided individual participant data (IPD) (255 830 participant-years). Eleven studies provided summary estimates (n = 24 109). Two-stage random-effects IPD meta-analyses found that men with baseline testosterone concentrations below 7.4 nmol/L (<213 ng/dL), LH concentrations above 10 IU/L, or estradiol concentrations below 5.1 pmol/L had higher all-cause mortality, and those with testosterone concentrations below 5.3 nmol/L (<153 ng/dL) had higher CVD mortality risk. Lower SHBG concentration was associated with lower all-cause mortality (median for quintile 1 [Q1] vs. Q5, 20.6 vs. 68.3 nmol/L; adjusted hazard ratio [HR], 0.85 [95% CI, 0.77 to 0.95]) and lower CVD mortality (adjusted HR, 0.81 [CI, 0.65 to 1.00]). Men with lower baseline DHT concentrations had higher risk for all-cause mortality (median for Q1 vs. Q5, 0.69 vs. 2.45 nmol/L; adjusted HR, 1.19 [CI, 1.08 to 1.30]) and CVD mortality (adjusted HR, 1.29 [CI, 1.03 to 1.61]), and risk also increased with DHT concentrations above 2.45 nmol/L. Men with DHT concentrations below 0.59 nmol/L had increased risk for incident CVD events. LIMITATIONS: Observational study design, heterogeneity among studies, and imputation of missing data. CONCLUSION: Men with low testosterone, high LH, or very low estradiol concentrations had increased all-cause mortality. SHBG concentration was positively associated and DHT concentration was nonlinearly associated with all-cause and CVD mortality. PRIMARY FUNDING SOURCE: Medical Research Future Fund, Government of Western Australia, and Lawley Pharmaceuticals. (PROSPERO: CRD42019139668).

Factors Associated With Circulating Sex Hormones in Men : Individual Participant Data Meta-analyses.

BACKGROUND: Various factors modulate circulating testosterone in men, affecting interpretation of testosterone measurements. PURPOSE: To clarify factors associated with variations in sex hormone concentrations. DATA SOURCES: Systematic literature searches (to July 2019). STUDY SELECTION: Prospective cohort studies of community-dwelling men with total testosterone measured using mass spectrometry. DATA EXTRACTION: Individual participant data (IPD) (9 studies; n = 21 074) and aggregate data (2 studies; n = 4075). Sociodemographic, lifestyle, and health factors and concentrations of total testosterone, sex hormone-binding globulin (SHBG), luteinizing hormone (LH), dihydrotestosterone, and estradiol were extracted. DATA SYNTHESIS: Two-stage random-effects IPD meta-analyses found a nonlinear association of testosterone with age, with negligible change among men aged 17 to 70 years (change per SD increase about the midpoint, -0.27 nmol/L [-7.8 ng/dL] [CI, -0.71 to 0.18 nmol/L {-20.5 to 5.2 ng/dL}]) and decreasing testosterone levels with age for men older than 70 years (-1.55 nmol/L [-44.7 ng/dL] [CI, -2.05 to -1.06 nmol/L {-59.1 to -30.6 ng/dL}]). Testosterone was inversely associated with body mass index (BMI) (change per SD increase, -2.42 nmol/L [-69.7 ng/dL] [CI, -2.70 to -2.13 nmol/L {-77.8 to -61.4 ng/dL}]). Testosterone concentrations were lower for men who were married (mean difference, -0.57 nmol/L [-16.4 ng/dL] [CI, -0.89 to -0.26 nmol/L {-25.6 to -7.5 ng/dL}]); undertook at most 75 minutes of vigorous physical activity per week (-0.51 nmol/L [-14.7 ng/dL] [CI, -0.90 to -0.13 nmol/L {-25.9 to -3.7 ng/dL}]); were former smokers (-0.34 nmol/L [-9.8 ng/dL] [CI, -0.55 to -0.12 nmol/L {-15.9 to -3.5 ng/dL}]); or had hypertension (-0.53 nmol/L [-15.3 ng/dL] [CI, -0.82 to -0.24 nmol/L {-23.6 to -6.9 ng/dL}]), cardiovascular disease (-0.35 nmol/L [-10.1 ng/dL] [CI, -0.55 to -0.15 nmol/L {-15.9 to -4.3 ng/dL}]), cancer (-1.39 nmol/L [-40.1 ng/dL] [CI, -1.79 to -0.99 nmol/L {-51.6 to -28.5 ng/dL}]), or diabetes (-1.43 nmol/L [-41.2 ng/dL] [CI, -1.65 to -1.22 nmol/L {-47.6 to -35.2 ng/dL}]). Sex hormone-binding globulin was directly associated with age and inversely associated with BMI. Luteinizing hormone was directly associated with age in men older than 70 years. LIMITATION: Cross-sectional analysis, heterogeneity between studies and in timing of blood sampling, and imputation for missing data. CONCLUSION: Multiple factors are associated with variation in male testosterone, SHBG, and LH concentrations. Reduced testosterone and increased LH concentrations may indicate impaired testicular function after age 70 years. Interpretation of individual testosterone measurements should account particularly for age older than 70 years, obesity, diabetes, and cancer. PRIMARY FUNDING SOURCE: Medical Research Future Fund, Government of Western Australia, and Lawley Pharmaceuticals. (PROSPERO: CRD42019139668).

Association Between Testosterone Treatment and Risk of Incident Cardiovascular Events Among US Male Veterans With Low Testosterone Levels and Multiple Medical Comorbidities.

Background Testosterone treatment is common in men, although risks for major cardiovascular events are unclear. Methods and Results A study was conducted in US male veterans, aged ≥40 years, with low serum testosterone and multiple medical comorbidities and without history of myocardial infarction, stroke, venous thromboembolism, prostate cancer, or testosterone treatment in the prior year. For the primary outcome, we examined if testosterone treatment was associated with a composite cardiovascular outcome (incident myocardial infarction, ischemic stroke, or venous thromboembolism). Testosterone use was modeled as intramuscular or transdermal and as current use, former use, and no use. Current testosterone users were compared with former users to reduce confounding by indication. The cohort consisted of 204 857 men with a mean (SD) age of 60.9 (9.9) years and 4.7 (3.5) chronic medical conditions. During follow-up of 4.3 (2.8) years, 12 645 composite cardiovascular events occurred. In adjusted Cox regression analyses, current use of transdermal testosterone was not associated with risk for the composite cardiovascular outcome (hazard ratio [HR], 0.89; 95% CI, 0.76-1.05) in those without prevalent cardiovascular disease, and in those with prevalent cardiovascular disease was associated with lower risk (HR, 0.80; 95% CI, 0.70-0.91). In similar analyses, current use of intramuscular testosterone was not associated with risk for the composite cardiovascular outcome in men without or with prevalent cardiovascular disease (HR, 0.91; 95% CI, 0.80-1.04; HR, 0.98; 95% CI, 0.89-1.09, respectively). Conclusions In a large cohort of men without a history of myocardial infarction, stroke, or venous thromboembolism, testosterone treatment was not associated with increased risk for incident composite cardiovascular events.

Androgens In Men Study (AIMS): protocol for meta-analyses of individual participant data investigating associations of androgens with health outcomes in men.

INTRODUCTION: This study aims to clarify the role(s) of endogenous sex hormones to influence health outcomes in men, specifically to define the associations of plasma testosterone with incidence of cardiovascular events, cancer, dementia and mortality risk, and to identify factors predicting testosterone concentrations. Data will be accrued from at least three Australian, two European and four North American population-based cohorts involving approximately 20 000 men. METHODS AND ANALYSIS: Eligible studies include prospective cohort studies with baseline testosterone concentrations measured using mass spectrometry and 5 years of follow-up data on incident cardiovascular events, mortality, cancer diagnoses or deaths, new-onset dementia or decline in cognitive function recorded. Data for men, who were not taking androgens or drugs suppressing testosterone production, metabolism or action; and had no prior orchidectomy, are eligible. Systematic literature searches were conducted from 14 June 2019 to 31 December 2019, with no date range set for searches. Aggregate level data will be sought where individual participant data (IPD) are not available. One-stage IPD random-effects meta-analyses will be performed, using linear mixed models, generalised linear mixed models and either stratified or frailty-augmented Cox regression models. Heterogeneity in estimates from different studies will be quantified and bias investigated using funnel plots. Effect size estimates will be presented in forest plots and non-negligible heterogeneity and bias investigated using subgroup or meta-regression analyses. ETHICS AND DISSEMINATION: Ethics approvals obtained for each of the participating cohorts state that participants have consented to have their data collected and used for research purposes. The Androgens In Men Study has been assessed as exempt from ethics review by the Human Ethics office at the University of Western Australia (file reference number RA/4/20/5014). Each of the component studies had obtained ethics approvals; please refer to respective component studies for details. Research findings will be disseminated to the scientific and broader community via the publication of four research articles, with each involving a separate set of IPD meta-analyses (articles will investigate different, distinct outcomes), at scientific conferences and meetings of relevant professional societies. Collaborating cohort studies will disseminate findings to study participants and local communities. PROSPERO REGISTRATION NUMBER: CRD42019139668.

Testosterone treatment and the risk of aggressive prostate cancer in men with low testosterone levels.

PURPOSE: Testosterone treatment of men with low testosterone is common and, although relatively short-term, has raised concern regarding an increased risk of prostate cancer (CaP). We investigated the association between modest-duration testosterone treatment and incident aggressive CaP. MATERIALS AND METHODS: Retrospective inception cohort study of male Veterans aged 40 to 89 years with a laboratory-defined low testosterone measurement from 2002 to 2011 and recent prostate specific antigen (PSA) testing; excluding those with recent testosterone treatment, prostate or breast cancer, high PSA or prior prostate biopsy. Histologically-confirmed incident aggressive prostate cancer or any prostate cancer were the primary and secondary outcomes, respectively. RESULTS: Of the 147,593 men included, 58,617 were treated with testosterone. 313 aggressive CaPs were diagnosed, 190 among untreated men (incidence rate (IR) 0.57 per 1000 person years, 95% CI 0.49-0.65) and 123 among treated men (IR 0.58 per 1000 person years; 95% CI 0.48-0.69). After adjusting for age, race, hospitalization during year prior to cohort entry, geography, BMI, medical comorbidities, repeated testosterone and PSA testing, testosterone treatment was not associated with incident aggressive CaP (HR 0.89; 95% CI 0.70-1.13) or any CaP (HR 0.90; 95% CI 0.81-1.01). No association between cumulative testosterone dose or formulation and CaP was observed. CONCLUSIONS: Among men with low testosterone levels and normal PSA, testosterone treatment was not associated with an increased risk of aggressive or any CaP. The clinical risks and benefits of testosterone treatment can only be fully addressed by large, longer-term randomized controlled trials.

Serum androgens and risk of atrial fibrillation in older men: The Cardiovascular Health Study.

BACKGROUND: Decline in serum androgens is common among older men and has been associated with cardiovascular disease, although its role in risk of atrial fibrillation (AF) has not been well defined. HYPOTHESIS: Low serum androgens are associated with an increased risk of AF. METHODS: We examined the prospective associations between testosterone, its more active metabolite dihydrotestosterone (DHT), and sex hormone-binding globulin (SHBG) with risk of AF among 1019 otherwise healthy men with average age 76.3 ±4.9 years in the Cardiovascular Health Study. RESULTS: After median follow-up of 9.5 years, 304 (30%) men developed AF. We detected a nonlinear association with risk of incident AF in both free and total DHT, in which subjects with the lowest levels had a higher risk of incident AF. After adjustment for demographics, clinical risk factors, left atrial diameter, and serum NT-proBNP levels, men with free DHT <0.16 ng/dL were at increased risk compared with men with higher levels (hazard ratio: 1.48, 95% confidence interval: 1.01-2.17, P <0.05). Sensitivity analyses confirmed that the increased risk was not cutpoint-specific, with a significant association noted up to cutpoints <~0.2 ng/dL. We also detected a complex nonlinear association between SHBG and incident AF, in which subjects in the middle quintile (52.9-65.3 nmol/L) had increased risk. CONCLUSIONS: Among older men, low free DHT is associated with an increased risk of incident AF. Further studies are needed to explore mechanisms for this association.

Testosterone, Dihydrotestosterone, Sex Hormone-Binding Globulin, and Incident Diabetes Among Older Men: The Cardiovascular Health Study.

Context: Although sex hormone-binding globulin (SHBG) and testosterone (T) have been inversely associated with risk of diabetes, few studies have examined dihydrotestosterone (DHT), a more potent androgen than T, in older adults, whose glycemic pathophysiology differs from younger adults. Objective: To determine the associations of SHBG, T, and DHT with insulin resistance and incident diabetes in older adult men. Design: In a prospective cohort study, we evaluated baseline levels of SHBG, T, and DHT using liquid chromatography-tandem mass spectrometry among 852 men free of diabetes and cardiovascular disease in the Cardiovascular Health Study in 1994. Main Outcome: Insulin resistance estimated by Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) and insulin sensitivity estimated by the Gutt index in 1996, and incident diabetes (n = 112) ascertained over a mean follow-up of 9.8 years. Results: In linear regression models adjusted for demographics, alcohol consumption, current smoking, body mass index, and other androgens, SHBG [HOMA-IR 0.30 units lower per doubling; 95% confidence interval (CI), 0.08 to 0.52; P = 0.01] and total DHT (HOMA-IR 0.18 units lower per doubling; 95% CI, 0.06 to 0.30; P = 0.01), but not free T (P = 0.33), were inversely associated with insulin resistance. In corresponding Cox proportional hazards models, total DHT was again inversely associated with risk of diabetes (adjusted hazard ratio per doubling, 0.69; 95% CI, 0.52 to 0.92; P = 0.01), but SHBG (hazard ratio, 1.09; 95% CI, 0.74 to 1.59; P = 0.66) and free T (hazard ratio, 1.15; 95% CI, 0.92 to 1.43; P = 0.23) were not. Conclusions: Among older men, higher levels of DHT were inversely associated with insulin resistance and risk of diabetes over the ensuing 10 years, whereas levels of T were not. Future studies are still needed to clarify the role of SHBG in risk of diabetes in this population.

Testosterone and dihydrotestosterone and incident ischaemic stroke in men in the Cardiovascular Health Study.

OBJECTIVE: Ischaemic stroke is a major cause of morbidity and mortality in elderly men. Our main objective was to examine whether testosterone (T) or dihydrotestosterone (DHT) was associated with incident ischaemic stroke in elderly men. DESIGN: Cohort study. PARTICIPANTS: Elderly men in the Cardiovascular Health Study who had no history of stroke, heart disease or prostate cancer as of 1994 and were followed until December 2010. MEASUREMENTS: Adjudicated ischaemic stroke. RESULTS: Among 1032 men (mean age 76, range 66-97), followed for a median of 10 years, 114 had an incident ischaemic stroke. Total T and free T were not significantly associated with stroke risk, while DHT had a nonlinear association with incident stroke (P = 0·006) in analyses adjusted for stroke risk factors. The lowest risk of stroke was at DHT levels of 50-75 ng/dl, with greater risk of stroke at DHT levels above 75 ng/dl or below 50 ng/dl. Results were unchanged when SHBG was added to the model. Calculated free DHT had an inverse linear association with incident ischaemic stroke with HR 0·77 (95% CI, 0·61, 0·98) per standard deviation in analyses adjusted for stroke risk factors. CONCLUSIONS: Dihydrotestosterone had a nonlinear association with stroke risk in which there was an optimal DHT level associated with the lowest stroke risk. Further studies are needed to confirm these results and to clarify whether there is an optimal androgen range associated with the least risk of adverse outcomes in elderly men.

Testosterone treatment and mortality in men with low testosterone levels.

CONTEXT: Low testosterone levels in men have been associated with increased mortality. However, the influence of testosterone treatment on mortality in men with low testosterone levels is not known. OBJECTIVE: The objective of the study was to examine the association between testosterone treatment and mortality in men with low testosterone levels. DESIGN: This was an observational study of mortality in testosterone-treated compared with untreated men, assessed with time-varying, adjusted Cox proportional hazards regression models. Effect modification by age, diabetes, and coronary heart disease was tested a priori. SETTING: The study was conducted with a clinical database that included seven Northwest Veterans Affairs medical centers. PATIENTS: Patients included a cohort of 1031 male veterans, aged older than 40 yr, with low total testosterone [≤250 ng/dl (8.7 nmol/liter)] and no history of prostate cancer, assessed between January 2001 and December 2002 and followed up through the end of 2005. MAIN OUTCOME MEASURE: Total mortality in testosterone-treated compared with untreated men was measured. RESULTS: Testosterone treatment was initiated in 398 men (39%) during routine clinical care. The mortality in testosterone-treated men was 10.3% compared with 20.7% in untreated men (P<0.0001) with a mortality rate of 3.4 deaths per 100 person-years for testosterone-treated men and 5.7 deaths per 100 person-years in men not treated with testosterone. After multivariable adjustment including age, body mass index, testosterone level, medical morbidity, diabetes, and coronary heart disease, testosterone treatment was associated with decreased risk of death (hazard ratio 0.61; 95% confidence interval 0.42-0.88; P = 0.008). No significant effect modification was found by age, diabetes, or coronary heart disease. CONCLUSIONS: In an observational cohort of men with low testosterone levels, testosterone treatment was associated with decreased mortality compared with no testosterone treatment. These results should be interpreted cautiously because residual confounding may still be a source of bias. Large, randomized clinical trials are needed to better characterize the health effects of testosterone treatment in older men with low testosterone levels.

Low serum testosterone and mortality in male veterans.

BACKGROUND: Low serum testosterone is a common condition in aging associated with decreased muscle mass and insulin resistance. This study evaluated whether low testosterone levels are a risk factor for mortality in male veterans. METHODS: We used a clinical database to identify men older than 40 years with repeated testosterone levels obtained from October 1, 1994, to December 31, 1999, and without diagnosed prostate cancer. A low testosterone level was a total testosterone level of less than 250 ng/dL (<8.7 nmol/L) or a free testosterone level of less than 0.75 ng/dL (<0.03 nmol/L). Men were classified as having a low testosterone level (166 [19.3%]), an equivocal testosterone level (equal number of low and normal levels) (240 [28.0%]), or a normal testosterone level (452 [52.7%]). The risk for all-cause mortality was estimated using Cox proportional hazards regression models, adjusting for demographic and clinical covariates over a follow-up of up to 8 years. RESULTS: Mortality in men with normal testosterone levels was 20.1% (95% confidence interval [CI], 16.2%-24.1%) vs 24.6% (95% CI, 19.2%-30.0%) in men with equivocal testosterone levels and 34.9% (95% CI, 28.5%-41.4%) in men with low testosterone levels. After adjusting for age, medical morbidity, and other clinical covariates, low testosterone levels continued to be associated with increased mortality (hazard ratio, 1.88; 95% CI, 1.34-2.63; P<.001) while equivocal testosterone levels were not significantly different from normal testosterone levels (hazard ratio, 1.38; 95% CI, 0.99%-1.92%; P=.06). In a sensitivity analysis, men who died within the first year (50 [5.8%]) were excluded to minimize the effect of acute illness, and low testosterone levels continued to be associated with elevated mortality. CONCLUSIONS: Low testosterone levels were associated with increased mortality in male veterans. Further prospective studies are needed to examine the association between low testosterone levels and mortality.

Increased incidence of diagnosed depressive illness in hypogonadal older men.

CONTEXT: Age-associated hypogonadism (testosterone deficit) occurs in 30% of men after the age of 55; it is associated with decreased muscle mass, bone mineral density, and libido, and with anorexia, fatigue, and irritability. Although some of these symptoms overlap with those of depression, the association between the 2 disorders is unclear. OBJECTIVE: To determine if hypogonadal men have an increased incidence of depressive illness compared with eugonadal men. DESIGN: Historical cohort study using computerized medical records, followed by a manual medical record review. SETTING: Veterans Affairs Puget Sound Health Care System. PARTICIPANTS: Two hundred seventy-eight men 45 years and older, without prior diagnosed depressive illness and with consistently normal or low testosterone levels (total testosterone level < or =200 ng/dL [< or =6.94 nmol/L]; or free testosterone level < or =0.9 ng/dL [< or =0.03 nmol/L]) at baseline and during a 2-year follow-up period. MAIN OUTCOME MEASURES: Incidence of, and time to, a depression diagnosis. RESULTS: The 2-year incidence of diagnosed depressive illness was 21.7% in hypogonadal men vs 7.1% in others (chi2(1)=6.0, P=.01). A Kaplan-Meier survival analysis showed a significant difference between hypogonadal and eugonadal men in time to diagnosed depression (log-rank test chi2(1)=6.9, P=.008). We used Cox proportional hazards regression models to examine the association of hypogonadism and time to depression diagnosis, adjusting for age, race, number of clinic visits, alcohol use disorders, prostate cancer, and overall medical comorbidity. The unadjusted hazard ratio for depression with hypogonadism was 3.5 (95% confidence interval, 1.3-9.4) (P=.01). Controlling for all covariates, hypogonadism remained significantly associated with depression (adjusted hazard ratio, 4.2; 95% confidence interval, 1.5-12.0) (P=.008). CONCLUSIONS: Hypogonadal men showed an increased incidence of depressive illness and a shorter time to diagnosis of depression. Further prospective studies are needed to confirm these preliminary findings and to clarify the role of testosterone in the treatment of depressive illness in older men.