Effect of Testosterone Treatment on Bone Mineral Density in Men Over 65 Years of Age

As men age, their serum testosterone concentrations decrease, as do their bone densities. Because bone density is also low in hypogonadal men, we hypothesized that increasing the serum testosterone concentrations of men over 65 yr to those found in young men would increase their bone densities. We randomized 108 men over 65 yr of age to wear either a testosterone patch or a placebo patch double blindly for 36 months. We measured bone mineral density by dual energy x-ray absorptiometry before and during treatment. Ninety-six men completed the entire 36-month protocol. The mean serum testosterone concentration in the men treated with testosterone increased from 367 ± 79 ng/dL (±sd; 12.7 ± 2.7 nmol/L) before treatment to 625 ± 249 ng/dL (21.7 ± 8.6 nmol/L; P < 0.001) at 6 months of treatment and remained at that level for the duration of the study. The mean bone mineral density of the lumbar spine increased (P < 0.001) in both the placebo-treated (2.5± 0.6%) and testosterone-treated (4.2 ± 0.8%) groups, but ...