Tens of thousands of men, including many HIV-positive men with low testosterone levels, are trying testosterone shots, patches, and gel hormone-replacement products in hopes of regaining youthful vigor and virility. But a new report uncovers little evidence these treatments work--or are even safe. "Certainly there are people out there who say testosterone replacement therapy is just wonderful and others who say it doesn't do any good at all. What we're saying is we just don't know," said Dan Blazer of Duke University Medical Center, who led an Institute of Medicine probe of the therapy.
The study, commissioned by the National Institutes of Health, shows that very little is known about the effectiveness and long-term risks of male hormone replacement therapy. Only a few studies have been done, all very small and lasting only months, according to the report. That's far too little information to tell if testosterone offers any benefit to men who aren't markedly deficient in the hormone--much less whether it's safe, concluded a panel of experts in hormones and men's health. The chief safety concern is that boosting testosterone levels for long periods could spur the growth of prostate cancer, already a big risk as men age. The report urges the NIH to begin a series of long-term research projects to examine these issues.
Demand for prescription testosterone treatment by men whose natural hormone levels are near normal is rising rapidly, the study found. The Food and Drug Administration has approved testosterone therapy for men with hypogonadism, including those with HIV infection, where the body makes very little testosterone. An estimated 4 million to 5 million Americans have hypogonadism, but only about 5% are thought to be getting treatment. But more than 1.75 million prescriptions for testosterone products were written in 2002--a 170% increase from 1999--for an estimated 800,000 patients, meaning a lot of men using testosterone may be using the products even though they are not suffering from hypogonadism.