The moderating impact of lifestyle factors on sex steroids, sexual activities and aging in Asian men.

The present study sought to evaluate the relative associations of exercise, sleep and other lifestyle habits with aging, sex hormones, percent body fat (%BF) and sexual activities in men living in the community. A better understanding of this complex interrelationship is important in helping the formulation of modalities for a holistic approach to the management of aging men. The results showed that age is a major determinant for many physiological parameters, including sleep, hormonal and metabolic parameters, some lifestyle factors and sexual activities. Testosterone (T), bioavailable testosterone (BioT) and dehydroepiandrosterone sulphate (DHEAS) concentrations decreased with age, while estradiol (E2), sex hormone-binding globulin (SHBG) and %BF increased with age. In addition, there exist intricate associations among hormonal and lifestyle factors, %BF and age. High-intensity exercise and longer duration of sleep were associated with higher concentrations of T and BioT. T was shown to be associated positively with men who were engaged in masturbation. DHEAS was associated with men wanting more sex and with good morning penile rigidity. Older Singaporean men tended to sleep for shorter duration, but exercised more intensely than younger men. Coital and masturbation frequencies decreased with age, and a significantly greater number of younger men were engaged in masturbation. Relationship between the partners is a key determinant of sexuality in men. It appears that T may have a limited, while dehydroepiandrosterone (DHEA) have a greater role than previously suggest, as a motivational signal for sexual function in men. Both biological and psychosocial factors interact with each other to influence sexual functions in men. Hence, a biopsychosocial approach may be more appropriate for a more lasting resolution to sexual dysfunctions in men.

Association of age and physical exercise with bodyweight and body composition in Asian Chinese men.

BACKGROUND: The present study sought to examine the association between physical exercise as a lifestyle habit with anthropometric parameters and body composition and aging in men. METHODS: Intensity of exercise was scored as metabolic equivalent-min/week (MET-min/week) from data of the questionnaire, while anthropometric parameters and body composition were carried out by standard measuring instruments and dual-energy X-ray absorptiometry scanner, respectively. RESULTS: Age was associated with decreases in bodyweight, height, total lean mass and bone mass, but an increase in fat mass. The negative association of lean mass with age was predominantly due to the negative association of lean masses in the legs and arm, while the positive association of fat mass with age was primarily due to the positive association of fat masses in the trunk and abdomen. Exercise of intensity greater than 1000 MET-min/week was significantly associated with higher lean and bone masses and lower fat mass. The increase in lean mass was predominantly in the legs, while the decreases in fat mass were in the trunk and abdomen. CONCLUSION: The study showed that the high intensity of physical exercise, equivalent to greater than 1000 MET-min/week, is required to effect beneficial changes in the body composition. Hence, results from the study support the importance of promoting a lifestyle habit of exercise of sufficient intensity in order to mitigate the increase risks of sarcopenia and obesity and their attendant ill effects on health in men as they age.

Association between an intronic apolipoprotein E polymorphism and bone mineral density in Singaporean Chinese females.

INTRODUCTION: Apolipoprotein E (ApoE) is implicated in the pathogenesis of osteoporosis. OBJECTIVE: To investigate possible association of the non-classical APOE gene +113C/G (rs440446) intron 1 enhancer polymorphism with bone mineral density (BMD) in a homogeneous Chinese population in Singapore. METHODS: A total of 655 volunteers, males and females, aged between 31 and 72 years, from the public participated. BMD was measured using dual-energy X-ray absorptiometry and APOE +113C/G (rs440446) genotypes were determined by Sequenom MassARRAY system. To adjust for potential confounders, anthropometric, demographic, and lifestyle determinants were obtained, and serum lipids and E(2) were measured. RESULTS: The +113C/G (rs440446) polymorphism within the APOE gene was associated with BMD in Chinese Singaporean females only. Females with the heterozygous CG genotype were significantly associated with reduced total, lumbar spine, and femoral neck of hip BMD, after multilevel adjustment of confounders. The association was stronger in the spine than in the hip. When females were stratified according to WHO classification for osteoporosis, those with CG and GG genotypes had increased risk (OR 3.50 and 2.22, respectively) of developing osteopenia/osteoporosis in the lumbar spine. Serum lipids did not explain the influence of APOE +113 C/G (rs440446) on BMD. CONCLUSION: This study demonstrated an association between APOE +113C/G (rs440446) polymorphism with measures of BMD in Singaporean Chinese females.

Sleep, sex steroid hormones, sexual activities, and aging in Asian men.

This was a cross-sectional study to examine the different associations of age and sleep duration with sex steroid hormones and sexual activities in 531 Asian Chinese men aged between 29 and 72 years old. Sleep duration and sexual activities were evaluated through a self-administered questionnaire, and total testosterone (T), sex hormone-binding globulin (SHBG), estradiol (E2), and dehydroepiandrosterone sulfate (DHEAS) were measured by established immunoassay methods in a single blood sample collected between 8:00 and 11:00 am. Bioavailable T (BioT) was calculated using the Vermeulen formula. Age was a major determinant of sleep, sex steroid hormones, and sexual activities in men. BioT, DHEAS, coital frequency, masturbation, and sleep duration declined with age. On the other hand, SHBG and E2 increased with age. Sleep duration, independently of age, aerobic exercise, and body fat, was positively associated with T and BioT, but not with DHEAS, E2, or any of the sexual activities studied. Men who masturbated had higher levels of both T and BioT. DHEAS was significantly associated with coital frequency and desire for sex. The present study showed that besides age, sleep duration was associated with androgen concentrations in men, and thus the evaluation of sleep hygiene may be beneficial in the management of men with low androgen concentrations. DHEAS may be independently associated with some sexual functions in men.

Differential impact of aging and gender on lipid and lipoprotein profiles in a cohort of healthy Chinese Singaporeans.

AIM: To evaluate the impact of age and gender on lipid and lipoprotein profiles and the burden of dyslipidemia in a cohort of healthy Chinese Singaporean. METHODS: A total of 1 775 healthy Chinese, 536 men and 1 239 women aged between 30 and 70 years old were involved in the present study. RESULTS: Gender differences in all lipid and lipoprotein levels were clearly evident. Singaporean Chinese men have significantly higher levels of total cholesterol (TC), triglyceride (TG), low density lipoprotein-cholesterol (LDL-C) and total cholesterol/high density lipoprotein-cholesterol (TC/HDL-C), and lower levels of HDL-C than women. Although lipid and lipoprotein levels in men did not change in the different age groups, those in women, especially TC, LDL-C and TC/HDL-C, were significantly higher in older women (> 50 years old) than corresponding levels in younger women (30-46 years old). Furthermore, TG was significantly correlated with lipids and lipoproteins differently in men and women. If 100 mg/dL of LDL-C were to be adopted as the therapeutic cut-off level, then the burden of care will be huge as approximately 90% of both Chinese men and women have LDL-C greater than 100 mg/dL. CONCLUSION: In light of the findings of the present study, we suggest that preventive measures to promote the reduction in risk of coronary heart disease (CHD) must address the high proportion of men and women with high LDL-C, and that these measures should take into account both the gender and age factors. For men, reduction of high cholesterol must start early in life, whereas for women, steps must be taken earlier to mitigate the anticipated sharp increase in risk, especially after menopause.

Interactions among age, adiposity, bodyweight, lifestyle factors and sex steroid hormones in healthy Singaporean Chinese men.

AIM: To examine the inter-relationships among age, lifestyle factors, anthropometric parameters, percent body fat and steroid hormone parameters in 531 healthy Singaporean Chinese men aged between 29 and 72 years old. METHODS: Various lifestyle parameters were quantified through a survey, and testosterone (T), estradiol (E2), dehydroepiandrosterone sulphate (DHEAS) and sex hormone binding globulin (SHBG) were measured using established methods. Anthropometric parameters were collected and computed, and percent body fat (Siri) was measured using the DEXA scanner. RESULTS: SHBG, DHEAS, bioavailable-T (Bio-T), E2, Siri, Ht, W/H, W/Ht and work stress were independently correlated with age. Using multivariate analyses and adjusting for age and other related factors, exercise, smoking and alcohol consumption have positive impacts on androgen levels and body composition. However, black and green tea consumption was associated with negative effects on body composition and with higher levels of E2 and Free Estradiol Index (FEI). Men with shorter sleep duration had significantly lower T levels as compared to those with 6 h or more of nightly sleep. Higher T levels were associated with lower levels of adiposity and other indices of adiposity, whereas higher E2 levels were related to higher levels of adiposity. Men with higher DHEAS were significantly taller and heavier than those with low DHEAS levels. CONCLUSION: The study showed the close interactions among the gonadal/adrenal and metabolic compartments, with age being a key determinant in their interactions. Lifestyle factors such as exercise, smoking, sleeping and alcohol and tea consumption might play significantly roles in determining the status of health in men.

Are BMI and other anthropometric measures appropriate as indices for obesity? A study in an Asian population.

We have examined the relationships between percentage of body fat (PBF) and risk factors for cardiovascular disease and insulin resistance and how good body mass index (BMI) and other anthropometric measures are as indices of obesity. High PBF levels were associated with increased risk of cardiovascular disease and insulin resistance. The World Health Organization BMI of 30 kg/m(2) for obesity has low sensitivity, 6.7% and 13.4% for men and women, respectively. For every obese man and woman identified, 6.7 and 1.76 times nonobese men and women, respectively, will be misclassified as obese. With the locally established BMI cutoff point for obesity of 27 kg/m(2) for men and 25 kg/m(2) for women, the sensitivity was improved to 46.7% and 60.8%, respectively. For every obese man and woman identified, 3.76 and 1.64 times nonobese men and women, respectively, will be misclassified as obese. None of the other anthropometric indices was better than the locally established BMIs. We showed that the BMIs for obesity for our local men and women are different. These BMIs were most precise among all indices studied. However, they still lead to high false-positive rates. For more effective management of the problem of obesity, we need to develop more precise, simple, and cost-effective methods for the measurement of PBF.