ANDROGEN SUPPLEMENTATION IN EUGONADAL MEN WITH OSTEOPOROSIS - EFFECTSOF 6 MONTHS TREATMENT ON MARKERS OF BONE-FORMATION AND RESORPTION

There is no established treatment for osteoporosis in men, a common an d disabling condition the incidence of which is increasing rapidly. We conducted an open study to investigate the efficacy and mode of actio n of testosterone therapy in eugonadal men with osteoporotic vertebral crush fracture, Twenty-one men, aged 34-73 (mean 58), were treated wi th intramuscular testosterone esters (Sustanon 250(R)) every 2 weeks f or 6 months, Bone mineral density (BMD) measurement by dual-energy X-r ay absorptiometry was performed at baseline and 6 months, We also meas ured biochemical markers of bone turnover, testosterone, estradiol, se x hormone binding globulin (SHBG), and gonadotrophins at baseline and after 3 and 6 months of treatment, Treatment was well tolerated, and s ide effects were uncommon. Lumbar spine BMD increased by 5% from 0.799 to 0.839 g/cm(2) (p < 0.001), All bone markers decreased, indicating that treatment suppressed bone turnover. Although serum osteocalcin le vels fell only slightly, there were large reductions in urinary deoxyp yridinoline and N-telopeptide (p < 0.05), which mere correlated with t he increase in spinal BMD, Interpretation of the findings with other m arkers, such as bone-specific alkaline phosphatase and pyridinoline, w as confounded by the wide scatter of values, Serum testosterone increa sed by 55%, while SHBG decreased by 20%, leading to a rise in free and rogen of 90%. Serum estradiol also increased by 45%, The change in spi ne BMD was significantly con-elated with a change in serum estradiol b ut not with a change in serum testosterone, We therefore conclude that testosterone is a promising treatment for men with idiopathic osteopo rosis, acting to suppress bone resorption by a mechanism that may invo lve estrogen.