Risks of Testosterone Treatment

Testosterone has been increasingly prescribed in recent years, particularly for middle-aged and older men with relatively non-specific symptoms that mimic androgen deficiency. There has thus been considerable interest in understanding the risk–benefit ratio of testosterone treatment in older men who may be particularly vulnerable to some of the adverse effects of exogenous testosterone. The exact risks and patient-important benefits are currently unknown due to lack of data from adequate randomized control trials, but some helpful inferences can be made based on available data. Erythrocytosis, the most commonly reported adverse effect of testosterone therapy, has been reported to be 3–4 times more likely in men treated with testosterone as compared to placebo; however, the form of therapy may play a role with the highest risk seen in men receiving intramuscular testosterone therapy as compared to transdermal formulations. Reassuringly, current data do not demonstrate that exogenous testosterone causes de novo or worsens mild to moderate lower urinary tract symptoms; insufficient data exist in men with severe lower urinary tract symptoms as such men have usually been excluded from testosterone trials. Testosterone has not been demonstrated to cause prostate cancer, but is not recommended presently in men who either have a history of prostate cancer or are otherwise at high risk. The effects of testosterone treatment on cardiovascular disease risk are unknown. The majority of presently available data do not suggest an increased risk, but in the absence of adequately powered randomized controlled trials, caution in men with pre-existing cardiovascular disease is recommended. Overall, further data are needed to better understand both the benefits and risks of exogenous testosterone in older men.