Testosterone Replacement Therapy: Is It Safe?
Researchers Worry That Testosterone Use Is Way Ahead of Evidence
He says the studies offered "no clear evidence" of benefit from testosterone for the treatment of depression although some studies reported improvement in "quality of life and functional status." There was evidence for increased muscle mass but not for improved bone density. There was a trend toward improvement in spatial memory. And only men with a confirmed diagnosis of hypogonadism reported improved sexual desire.
In terms of risk, Kamerow says prostate specific antigen "will go up. But we don't really know if that is significant." Additionally, some studies found reported slight increases in LDL cholesterol (bad cholesterol).
In November 2003, the Institute of Medicine recommended that the NIH study testosterone replacement in small, placebo-controlled studies of men aged 65 or older.
Kamerow agrees studies are needed, but he says it would be more useful to include younger men in the studies. He notes that his research indicates that the bulk of testosterone prescriptions are "written for men aged 46 to 65."
Another difficulty, he says, will be identifying men with "low" testosterone. Women stop producing sex hormones at menopause, but men simply slow down with age. "Testosterone levels are actually highest at about age 17 and then begin to decline at a rate of about 1.2% a year," he says. Currently, a testosterone level of 300-1,000 ng/dL is considered normal.
Robert G. Harmon, MD, MPH, president of ACPM, tells WebMD that the overuse of testosterone is a concern for his organization. He advises against off-label use of testosterone replacement until "we know the true risks and benefits."
Harmon, who wasn't involved in Kamerow's study, says, "This is just another search for the fountain of youth, similar to the use of steroids or growth hormones. It is alarming."
He says that "exercise is a much better 'fountain of youth' than any pill or injection we could offer."
But while Kamerow says there is no evidence that backs up many of the testosterone marketing claims, he says he would prescribe it for men who "want to try it as a cure for the middle-aged blues." That said, he adds that prescribing testosterone would mean that he would closely follow the man with PSA levels as frequent as every six months.