Testosterone and andropause: the feasibility of testosterone replacement therapy in elderly men.

Andropause, a syndrome in aging men, consists of physical, sexual, and psychologic symptoms that include weakness, fatigue, reduced muscle and bone mass, impaired hematopoiesis, oligospermia, sexual dysfunction, depression, anxiety, irritability, insomnia, memory impairment, and reduced cognitive function. Free testosterone levels begin to decline at a rate of 1% per year after age 40 years. It is estimated that 20% of men aged 60-80 years have levels below the lower limit of normal. Although the causal relationship between declining testosterone levels and development of andropause symptoms is not firmly established, administration of testosterone to this population resulted in improvements in many areas. Most studies to date focused on physical benefits of testosterone replacement and failed to assess psychologic symptoms rigorously. Preliminary data suggest that therapy may benefit elderly men with new-onset depression. Testosterone administration is not without problems, the most worrisome being the potential for increased prostate cancer risk. Despite this concern, a limited number of studies administered the hormone weekly for up to 2 years, with only mild increases in prostate-specific antigen over control values. Currently, insufficient evidence, primarily regarding psychologic safety and efficacy, exists to warrant general administration of testosterone to elderly hypogonadal men. Further clinical investigations of this therapy in men with low testosterone levels and andropause symptoms are justified and necessary.