It’s controversial territory, the whole “Low T” arena, and will likely long remain so. But at least some serious data points are beginning to emerge in the form of the Testosterone Trials: a major set of government-funded, double-blind, placebo-controlled studies just published in the New England Journal of Medicine.
The seven linked trials examined the benefits of a year of testosterone gel (vs. placebo gel) in more than 700 men over age 65. It found those benefits to be “moderate,” and mainly for sexual function. Not vitality. Not much for physical functions like walking. A bit for mood. Overall, the Mighty T of the infomercial world is looking more like the modest T.
I spoke with Harvard Medical School’s Prof. Shalender Bhasin, director of the Research Program in Men’s Health: Aging and Metabolism at Brigham and Women’s Hospital and one of the lead researchers on the Testosterone Trials. Our conversation, lightly edited:
How would you sum up these findings?
The main finding of the Testosterone Trials was that testosterone treatment of older men with low testosterone levels has certain benefits, but the size of the benefits was modest. Testosterone improved all aspects of sexual function: It improved sexual activity, sexual desire, erections. Again, the magnitude of the effect was small, much smaller than the effect from previously approved medications for erectile dysfunction such as Viagra and Cialis.
The benefits on physical function and vitality were unclear. There was no improvement in vitality and there was a small improvement in walking ability whose clinical meaningfulness is not clear at the present time. And there was some improvement in mood. The trial was mostly an efficacy trial, so the long-term safety of testosterone still remains unclear. We need larger studies to address the issue of long-term safety, so that the risk-benefit ratio can be appropriately evaluated.
I must say that given all the buzz around testosterone, and the advertisements, the efficacy seems to be kind of underwhelming, doesn’t it? Continue reading