SEX-HORMONES AND BONE-MINERAL DENSITY IN ELDERLY MEN

The aim of this study was to determine the relationships between sex hormones and bone mineral density (BMD) in older men. Community-dwelling men (n = 134, mean age (SD) 69.5 (3.1) years) were recruited from two general practices in Cambridge, UK. Plasma total testosterone and sex hormone binding globulin (SHBG) were assayed and a free androgen index (FAI) was derived as the ratio of total testosterone to SHBG (x 100). Spine and hip BMD were measured by dual energy x-ray absorptiometry using the Hologic QDR-1000. After adjusting for age and body mass index (BMI), the FAI correlated with femoral neck (r = 0.20, P = 00.03), intertrochanteric, trochanteric and Ward's Triangle BMD (r = 0.22, P = 0.01). Analysis of variance, with adjustment for age and BMI, showed a progressive upward trend of hip BMD with increasing quartiles of FAI. The findings suggest that free testosterone plays a role in determining bone mineral density in older men.