Sex Hormone-binding Globulin Levels (sex + hormone-binding_globulin_level)

Distribution by Scientific Domains


Selected Abstracts


Erectile dysfunction is associated with low bioactive testosterone levels and visceral adiposity in men with type 2 diabetes

INTERNATIONAL JOURNAL OF ANDROLOGY, Issue 6 2007
D. Kapoor
Summary Low testosterone levels in men are associated with type 2 diabetes mellitus. Erectile dysfunction (ED) is a frequent complication of type 2 diabetes. The aim of our cross-sectional study was to investigate the relationship between ED and total, bioavailable and free testosterone levels in 198 men with type 2 diabetes. In addition, we examined the associations of various cardiovascular risk factors involved in the development of ED in type 2 diabetic men. We found that bioavailable and free testosterone levels were significantly lower in men with ED (p = 0.006 and 0.027 respectively) than those without ED. Sex hormone-binding globulin levels were also reduced, but there was no significant difference in total testosterone (TT) levels between men with and without ED. The severity of ED as assessed by International Index of Erectile Function scores was significantly associated with TT (r = 0.32; p < 0.001), bioavailable testosterone (r = 0.32; p < 0.001) and calculated free testosterone (r = 0.35; p < 0.001) levels. ED was more frequently observed in men with hypertension and a higher waist circumference (p = 0.03). There was also a higher prevalence of ED among smokers (p = 0.06), but there were no significant associations between ED and alcohol consumption or with BMI > 30. This study has shown that ED is associated with low bioavailable and free testosterone levels, age, visceral adiposity and hypertension in type 2 diabetic men. [source]


Letrozole normalizes serum testosterone in severely obese men with hypogonadotropic hypogonadism

DIABETES OBESITY & METABOLISM, Issue 3 2005
H. De Boer
Background:, Morbid obesity is associated with increased estradiol production as a result of aromatase-dependent conversion of testosterone to estradiol. The elevated serum estradiol levels may inhibit pituitary LH secretion to such extent that hypogonadotropic hypogonadism can result. Normalization of the disturbed estradiol-testosterone balance may be beneficial to reverse the adverse effects of hypogonadism. Aim:, To examine whether aromatase inhibition with Letrozole can normalize serum testosterone levels in severely obese men with hypogonadotropic hypogonadism. Patients and Methods:, Ten severely obese men, mean age 48.2 ± 2.3 (s.e.) years and body mass index 42.1 ± 2.6 kg/m2, were treated with Letrozole for 6 weeks in doses ranging from 7.5 to 17.5 mg per week. Results:, Six weeks of treatment decreased serum estradiol from 120 ± 20 to 70 ± 9 pmol/l (p = 0.006). None of the subjects developed an estradiol level of less than 40 pmol/l. LH increased from 4.5 ± 0.8 to 14.8 ± 2.3 U/l (p < 0.001). Total testosterone rose from 7.5 ± 1.0 to 23.8 ± 3.0 nmol/l (p < 0.001) without a concomitant change in sex hormone-binding globulin level. Those treated with Letrozole 17.5 mg per week had an excessive LH response. Conclusion:, Short-term Letrozole treatment normalized serum testosterone levels in all obese men. The clinical significance of this intervention remains to be established in controlled, long-term studies. [source]


Endogenous testosterone levels and smoking in men.

INTERNATIONAL JOURNAL OF ANDROLOGY, Issue 3 2007
The fifth Tromsų study
Summary Smoking is a risk factor of coronary heart disease (CHD), while the role of testosterone in the development of CHD is controversial. The reported effects of cigarette smoking on testosterone levels in men are conflicting, and smoking may be an important confounding factor when evaluating the relationship between testosterone levels and CHD. Thus, the objective of the present study was to examine the associations of smoking status and number of cigarettes smoked per day with total and free testosterone levels in a cross-sectional population-based study of 3427 men participating in the fifth Tromsų study. Total testosterone, luteinizing hormone, follicle-stimulating hormone and sex hormone-binding globulin levels were measured with immunoassay while free testosterone levels were calculated. Waist circumference was also measured and two standardized questionnaires were completed, including smoking status and number of cigarettes smoked. The data were analysed with analysis of variance and covariance and multiple regression analysis. Smoking men had significantly higher levels of total and free testosterone compared with men who never smoked (p < 0.001 and <0.01 respectively). Both total and free testosterone levels increased significantly with increasing number of cigarettes smoked daily (p < 0.001). Smoking men had 15% higher total and 13% higher free testosterone levels compared with men who never smoked. Thus, smoking seems to be an important confounding factor when evaluating testosterone levels, and could possibly mask borderline hypogonadism. [source]


Dehydroepiandrosterone Combined with Exercise Improves Muscle Strength and Physical Function in Frail Older Women

JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 9 2010
Anne M. Kenny MD
OBJECTIVES: To investigate the effects of dehydroepiandrosterone (DHEA) combined with exercise on bone mass, strength, and physical function in older, frail women. DESIGN: Double-blind, randomized, placebo-controlled trial. SETTING: A major medical institution. PARTICIPANTS: Ninety-nine women (mean age 76.6 ± 6.0) with low sulfated DHEA (DHEAS) levels, low bone mass, and frailty. INTERVENTION: Participants received 50 mg/d DHEA or placebo for 6 months; all received calcium and cholecalciferol. Women participated in 90-minute twice-weekly exercise regimens. MEASUREMENTS: Hormone levels, bone mineral density (BMD), bone turnover markers, body composition, upper and lower extremity strength, physical performance. RESULTS: Eighty-seven women (88%) completed 6 months. There were no significant changes in BMD or bone turnover markers. DHEA supplementation resulted in gains in lower extremity strength (from 459 ± 121 N to 484 ± 147 N; P=.01). There was also improvement in Short Physical Performance Battery score, a composite score that focuses on lower extremity function, in those taking DHEA (from 10.1 ± 1.8 to 10.7 ± 1.9; P=.02). There were significant changes in all hormone levels, including DHEAS, estradiol, estrone, and testosterone, and a decline in sex hormone-binding globulin levels in those taking DHEA. CONCLUSION: DHEA supplementation improved lower extremity strength and function in older, frail women involved in a gentle exercise program of chair aerobics or yoga. No changes were found in BMD either due to small sample size, short duration of study or no effect. The physical function findings are promising and require further evaluation as frail women are at high risk for falls and fracture. [source]