EFFECT OF AGE ON BONE-DENSITY AND BONE TURNOVER IN MEN

OBJECTIVE Little is known about the pattern of age-related bone loss i n men, and although androgens are required for optimum bone mass it is not clear whether the fall in bone mass with age in men Is related to falling androgens. DESIGN Cross-sectional measurement of bone density , at five sites, and markers of bone resorption and formation in 147 n ormal volunteers aged 20-83 years. SUBJECTS Healthy laboratory workers , hospital staff, their relatives, and husbands of women attending our osteoporosis clinic. MEASUREMENTS Forearm density (fat corrected), sp ine L2-L4, femoral neck, Ward's triangle and trochanter density; serum procollagen I C-terminal extension peptide, osteocalcin, bone alkalin e phosphatase and collagen I C-terminal telopeptide; fasting urine hyd roxyproline/creatinine, pyridinoline/creatinine and deoxypyridinoline/ creatinine; and free androgen index (FAI), measured as serum testoster one/sex hormone binding globulin. RESULTS Bone loss accelerated at mos t sites after age 50. There was a significant fall in FAI from the thi rd decade onwards. The levels of all bone markers fell with age. CONCL USIONS Bone loss in men appears to accelerate from age 50 and is assoc iated with decreased bone formation which may be associated with falli ng levels of free androgen.