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Background The age-related decline in testosterone levels is thought to be of great importance for male aging and cardiovascular diseases. However, data are controversial on whether abnormal sex hormones are linked to the presence of cardiovascular diseases and it is also uncertain how blood pressure modifies the association between testosterone levels and major cardiovascular diseases. Methods and Results This is a multicenter, population-based, cross-sectional study of 6296 men conducted between 2013 and 2016. Basic information and clinical symptoms were obtained by questionnaires. Blood pressure and plasma levels of total testosterone, sex hormone-binding globulin, luteinizing hormone, and free testosterone were determined in men in a multistage random, cluster sampling in 6 provinces of China. There were 5786 Chinese men (mean [SD] age 55.0 [10.1] years) included after exclusion criteria were applied; 37.2% (2150) of them were diagnosed with hypertension. Total testosterone, free testosterone, and sex hormone-binding globulin were inversely associated with the prevalence of hypertension. Age >65 years or body mass index ≥24 negatively impacted the inverse correlation between testosterone levels and hypertension, whereas smoking and family history of hypertension strengthened the correlation. In participants with grade 2 hypertension, total testosterone was positively associated with the presence of stroke, and luteinizing hormone was also positively correlated with cardiovascular and cerebrovascular diseases. Conclusions Lower total testosterone could be a promising risk marker for prevalent hypertension. Both low and high levels of testosterone are associated with greater cardiovascular risk. Primary hypogonadism may be a risk marker for major cardiovascular diseases in men with severe hypertension.

Few studies have investigated whether associations between smoking, sex hormone levels, and symptoms of late-onset hypogonadism (LOH) in men are affected by age. This multi-center, cross-sectional study involving 6,296 men aged 40-79 years was conducted between June 1, 2013 and August 31, 2016 in 6 provinces of China. Total testosterone, free testosterone, and Aging Males' Symptoms scale (AMS) scores were compared depending on smoking status and the number of cigarettes smoked. Total testosterone was higher in smokers than in non-smokers in all except the 70-79 year old subgroup. Free testosterone was higher in smokers than non-smokers for the 40-49 and 50-59 year old subgroups, but not the 60-69 and 70-79 year old subgroups. Total testosterone was positively associated with number of cigarettes consumed in smokers aged 40-49 and 50-59 years. Sexual and somatic AMS scores were higher in current and ex-smokers than in non-smokers in all age subgroups from 40 to 79 years and were negatively associated with cigarette consumption in smokers aged 40-49 years. These results indicate that, as men age, the positive association between smoking and testosterone weakens, while the positive association between smoking and LOH symptoms becomes stronger.

Late-onset hypogonadism (LOH) is a syndrome in middle-aged and elderly men caused by age-related testosterone deficiency. Age-related change of total testosterone (TT) of Asian males is different from Caucasian population, suggesting difference for LOH identification in Asians. A nationwide cross-sectional study involving six centers in China was conducted. Totally 6296 men aged 40-79 were recruited. After exclusions 5980 men were left for analyses. The serum TT level, was neither decreased with aging nor correlated with most hypogonadal symptoms. Instead, ten hypogonadal symptoms were found to be significantly correlated with free testosterone and testosterone secretion index, thus were chosen to form a concise scale. Further analysis identified a level of free testosterone <210 pmol/L, testosterone secretion index <1.8, and the concise scale score ≧17 could be diagnosed as having significantly aggravated LOH. This study developed an evidence-based criteria for LOH identification in Chinese population and may be adopted in other Asians. It includes the impaired testosterone secretion ability and deficiency of bioavailable testosterone, which should be the main cause in LOH pathogenesis despite normal TT levels, as well as correlated multiple hypogonadal symptoms. Our results may guide the LOH treatment to increase testicular function of testosterone secretion and bioavailable testosterone.

Background: Age-related differences of sex hormones are traditionally considered detrimental to certain diseases particularly in middle-aged and elderly males, however, it is imprudent to conclude without elucidating the influences of other age-related pathophysiology apart from reproductive aging. We sought to examine serum testosterone and sex hormone-binding globulin (SHBG) levels from different decades of life and their associations with the prevalence of diabetes in each respective decade., Materials and Methods: A total of 6296 males participated in this multicenter cross-sectional study, aged between 40-79 years. Information on diabetes and associated risk factors were obtained by questionnaires. Serum total testosterone (TT), SHBG and calculated free testosterone (fT) were determined., Results: Age-related stable level of TT even with significantly lower level of fT did not result in a higher age-related odds of diabetes. Whereas, age-related higher SHBG level was associated with a lower age-related odds of diabetes [-5.88 % (p = 0.038), -14.28 % (p = 0.003) and -23.53 % (p = 0.001) for males aged 50-59, 60-69, 70-79 years, respectively]. Also, the combined age-related differences of TT and SHBG levels were found associated with a lower age-related odds of diabetes [-2.21 % (p = 0.040), -8.16 % (p = 0.025) and -14.37 % (p = 0.002) for males aged 50-59, 60-69, 70-79 years, respectively]., Conclusions: The differences in hormonal levels of each age group category showed a negative association with the prevalence of diabetes in middle-aged and elderly males, however, this association could be deterred in the presence of obesity., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Decreased total testosterone (TT) is the recommended metric to identify age-related hypogonadism. However, average TT and the extent to which it varies by age, can vary substantially among different populations. Population-specific reference ranges are needed to understand normal versus abnormal TT levels. Therefore, the goal for this study was to describe androgen concentrations and their correlates among Western Chinese men. We completed a population-based, cross-sectional study including 227 young adults (YA) (20-39 years) and 939 older adults (OA) (40-89 years). We measured TT, sex-hormone binding globulin (SHBG), luteinizing hormone (LH), testosterone secreting index (TSI), and calculated free testosterone (cFT). Reference ranges for this population were determined using average YA concentrations. Multivariable regression models were used to predict hormone concentrations adjusting for age, waist-to-height ratio (WHR), marital status, education, occupation, smoking, alcohol, blood glucose, and blood pressure. Among OA, 3.8% had low TT, 15.2% had low cFT, 26.3% had low TSI, 21.6% had high SHBG, and 6.1% had high LH. Average cFT was significantly lower in OA (0.30 nmol/L; standard deviation (SD): 0.09) versus YA (0.37; SD: 0.11) but TT was not different in OA (16.82 nmol/L; SD: 4.80) versus YA (16.88; SD: 5.29). In adjusted models increasing age was significantly associated with increased SHBG or LH, and decreased cFT or TSI; however, TT was not significantly associated with age (β = 0.02 nmol/L; 95% confidence interval (CI): -0.01, 0.04). Higher WHR was associated with significantly decreased TT, SHBG, TSI, and LH. The only variable significantly related to cFT was age (β = -0.0033; 95% CI:-0.0037, -0.0028); suggesting that cFT measurements would not be confounded by other lifestyle factors. In conclusion, cFT, but not TT, varies with age in this population, suggesting cFT may be a better potential marker for age-related androgen deficiency than TT among Western Chinese men., Competing Interests: The authors have declared that no competing interests exist.

Context: Hormonal male contraceptive regimens effectively and reversibly suppress sperm production, but there are few large-scale efficacy studies., Objective: The safety, contraceptive efficacy, reversibility, and feasibility of injectable testosterone undecanoate (TU) in tea seed oil as a hormonal male contraceptive was assessed., Design: This was a multicenter, phase III, contraceptive efficacy clinical trial., Participants: A total of 1045 healthy fertile Chinese men were recruited throughout China into the study., Intervention(s): Injections of 500 mg TU were administered monthly for 30 months. A definition of severe oligozoospermia (< or =1 x 10(6)/ml) was used as a criterion of spermatogenic suppression and as the threshold for entering the contraceptive efficacy phase., Main Outcome Measure(s): The primary outcome was pregnancy rate in the partner. Other outcomes include: semen parameters, testis volumes, reproductive hormone levels, and safety laboratory tests., Results: Forty-three participants (4.8%) did not achieve azoospermia or severe oligozoospermia within the 6-month suppression phase. A total of 855 participants entered into the efficacy phase, and 733 participants completed monthly TU treatment and follow-up. There were nine pregnancies in 1554.1 person-years of exposure in the 24-month efficacy phase for a cumulative contraceptive failure rate of 1.1 per 100 men. The combined method failure rate was 6.1%, comprising 4.8% with inadequate suppression and 1.3% with postsuppression sperm rebound. No serious adverse events were reported. Spermatogenesis returned to the normal fertile reference range in all but two participants., Conclusions: Monthly injection of 500 mg TU provides safe, effective, reversible, and reliable contraception in a high proportion of healthy fertile Chinese men.