Benefits and Risks of Testosterone Treatment of Older Men with Hypogonadism.

Total and free testosterone levels decline in men with advancing age due to defects at all levels of the hypothalamic-pituitary-testicular axis. Testosterone treatment of older men with low testosterone levels is associated with improvements in sexual activity, sexual desire, and erectile function; lean body mass, muscle strength, and stair climbing power, and self-reported mobility; areal and volumetric bone mineral density, and estimated bone strength; depressive symptoms; and anemia. Long-term risks of cardiovascular events and prostate cancer during testosterone treatment remain unknown.