The Relationship between Sex Hormones and Bone Turnover Markers in Adult Men

BACKGROUND: Bone mass changes in men is related to age, BMI, sex hormones and other factors. In prior studies, bone markers were negatively correlated with bone mineral density, free testosterone, and estrogen and was positively correlated with SHBG. In a study of sex hormones and bone markers in Korean men estradiol was negatively correlated with deoxypyridinoline. In this study, the relationship of testosterone, estradiol, calculated free testosterone, FEI and SHBG to bone turnover markers in adult men were investigated. METHODS: This was a cross-sectional study of 184 men who had undertaken a health screening program in one general hospital in Bundang from November, 2001 to February, 2003. We surveyed information concerning the past medical history, current medication, alcohol consumption amount per week and smoking amount by means of self questionnaire records. Serum total testosterone, estradiol, SHBG and osteocalcin, alkaline phosphatase were measured at a fasting state. Urine was tested for deoxypyridinoline. Free testosterone was calculated using albumin, SHBG, and total testosterone level. RESULTS: Deoxypyridinoline adjusted by age, BMI was negatively correlated with FEI (r=-0.17, P=0.020) and was positively correlated with smoking amount (r=0.20 P= 0.007). Osteocalcin was negatively correlated with calculated free testosterone and ethanol consumption amount (r=-0.186, P=.0.12, r=-0.186, P=0.012). Multiple regression analysis showed that the most powerful factor influencing deoxypyridinoline was smoking amount (R2= 0.046), followed by FEI, BMI, and the one influencing osteocalcin was BMI (R2=0.050), ethanol amount and calculated free testosterone. After adjusting for age, BMI, drinking amount and smoking amount FEI shown to be a predictor of deoxypyridinoline (beta=-0.08, p<0.01, R2=0.101). After adjusting for age, BMI, and drinking amount calculated free testosterone was shown to be a predictor of osteocalcin (beta=-0.570, P<0.01, R2=0.130) in multiple regression model. CONCLUSIONS: In adult men, FEI shown to be a predictor of deoxypyridinoline and calculated free testosterone to be a predictor of osteocalcin as an independent variable.

The Relationship between Testosterone and Bone Mineral Density in Middle Aged Men

BACKGROUND: With the population aging, osteoporosis is becoming a major health issue. Although not as common as women, osteoporosis and its clinical end point of fracture are significant health care concern in men. Despite the considerable public health burden, our understanding of their pathogenesis is incomplete, and several factors known to affect bone metabolism in men are still controversial. So this study was made to investigate relationship between testosterone and bone mineral density in men. METHODS: This was a cross-sectional study of 432 men undertaken health screening program in Pundang CHA General Hospital from January 2000 to December 2000. We surveyed information concerning exercise and consumption of alcohol and smoking by means of self questionnaire records. Serum total testosterone, SHBG, and osteocalcin were measured at a fasting state. Second morning urine was tested for deoxypyridinoline. BMD was assessed using pQCT. RESULTS: FTI (free testosterone index) was positively correlated with BMD (r=0.265, P<0.01). Age, osteocalcin, SHBG, and urine deoxypridinoline were negatively correlated with BMD (r= 0.397, P<0.01, r= 0.121, P<0.05, r= 0.214, P<0.01, and r= 0.126, P<0.01). BMI and total testosterone had no significant correlation with BMD, and there were no apparent association among the level of alcohol and tobacco use, regular exercise and BMD. FTI was not independently correlated with BMD after age, BMI and urine deoxypyridinoline were adjusted, but showed a trend to significantly predict BMD (beta =0.10, P=0.052). CONCLUSION: These data suggest that FTI may play a role in determination of BMD in men, allowing the potential for clinical intervention. But further investigation of the role of testosterone in bone metabolism in men is necessary.

The Relationship among Testosterone, IGF- 1 and Fat Mass

BACGROUND: The age-related increase in fat mass seems related to decrease in hormone level. Few studies have been done in Korea concerning the association between testosterone, GH (growth hormone) and fat mass. This study was undertaken to evaluate the relationship among testosterone, IGF-1 and fat mass. METHODS: The study was performed from February to October 2001 in the Health Screening Center of Pundang CHA Hospital with 243 men as subjects. Fat intake was measured through interview with diet therapist and other data were obtained by self-questionnaire. Fat mass was measured using Inbody 3.0 and the level of total testosterone, SHBG and IGF-1 in serum were measured. RESULTS: Smoking was negatively correlated with fat mass and WHR (waist to hip ratio) (P <0.05) and fat intake was positively correlated with fat mass (P <0.05). Fat mass was negatively correlated with total testosterone, calculated free testosterone, and SHBG (gamma = 0.26; P <0.01, gamma = 0.15; P <0.05, gamma = 0.31; P <0.01). WHR was positively correlated with age (gamma =0.26; P <0.01) and negatively correlated with total testosterone, calculated free testosterone, and IGF-1 (gamma = 0.24; P <0.01, gamma = 0.20; P <0.01, gamma = 0.16; P <0.05). After adjustment for age, body mass index, smoking, and fat intake, the calculated free testosterone and IGF-1 were independently negatively correlated with fat mass (beta = 0.072; P <0.01, beta = 0.0035; P <0.05) and WHR (beta = 6.9E-04; P <0.05, beta = 4.0E-05; P <0.05) but, total testosterone and SHBG were not independently correlated with fat mass and WHR. CONCLUSION: The results indicate that the calculated free testosterone and IGF-1 can be independent determinants of fat mass and WHR in middle-aged men.