Bone density and bone-related biochemical variables in normal men: a longitudinal study
F Scopacasa1, J M Wishart, A G Need
1Department of Medicine, University of Adelaide, South Australia, Australia. franca.scopacasa@adelaide.edu.au
Background:
The objective of this study was to determine the pattern of forearm bone loss and its relationship to markers of bone turnover and sex steroids in normal men. This was a longitudinal study over a median interval of 41 months. The study was conducted in Adelaide, Australia. Study participants were 123 healthy male subjects, between the ages of 20 and 83 years.
Methods:
Fat-corrected forearm bone mineral content (fcBMC), markers of bone formation (alkaline phosphatase, osteocalcin, procollagen type 1 C-terminal extension peptide) and bone resorption (collagen type I cross-linked telopeptide, hydroxyproline/creatinine, pyridinoline/creatinine, and deoxypyridinoline/creatinine), calculated serum bioavailable testosterone, and serum estradiol were measured.
Results:
The mean time-weighted rate of change in forearm fcBMC was -0.33% +/- 0.72 (SD) per year. Bone loss commenced after 30 years of age and increased with age (p <.001), particularly after age 70 years. There was no relationship between the rate of change in fcBMC and either markers of bone turnover or serum sex steroids.
Conclusions:
In normal men, bone loss increases with age; there does not appear to be any relationship between this loss and either markers of bone turnover or levels of free androgen or estrogen.
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