New study adds caution to testosterone therapy for “low T”

Mass marketing of testosterone therapy may have men eager to try this seemingly simple fix. But the latest science should have them scratching their heads and putting away the credit card—at least for now.

A new study published in the online journal PLOS One shows an increase in the risk of having a heart attack in the months after starting testosterone therapy. The potential for danger was highest in older men. A report in the November 6, 2013, issue of JAMA showed that men who used testosterone therapy didn’t fare as well after artery-opening angioplasty as men who didn’t take testosterone.

A word of warning about these reports: neither was the type of study that can prove cause and effect. They can only show associations, or links. That means there’s no smoking gun here that testosterone therapy is harmful. But the studies do suggest caution.

On Friday, the FDA announced it would look into possible links between testosterone therapy and heart attack, stroke, or death in men taking FDA-approved testosterone products. In an announcement, it urged health care professionals to “consider whether the benefits of FDA-approved testosterone treatment is likely to exceed the potential risks of treatment.”

Potential risks as well as benefits

Millions of American men use a gel, patch, or injection to boost their testosterone levels. Getting extra testosterone can help those with truly low testosterone that is causing problems such as loss of bone and muscle or a low sex drive. What it can do for men with borderline low testosterone, or those without symptoms, is up in the air. As the February 2014 Harvard Men’s Health Watch reports, “The ongoing pharmaceutical marketing blitz promises that treating ‘low T’ this way can make men feel more alert, energetic, mentally sharp, and sexually functional.” What it doesn’t point out are the possible risks, according to Daniel Pendick, the newsletter’s executive editor.

Testosterone doesn’t immediately agree with a small number of men. They quickly develop acne, enlarged or tender breasts, or swelling in the ankles. In some men, testosterone causes an overproduction of red blood cells, which can increase the risk of developing blood clots inside arteries or veins.

The long-term risks aren’t really known. As the articles described above suggest, taking extra testosterone could pose problems for the heart. There are also worries that testosterone therapy could stimulate the growth of prostate cancer. But the evidence is mixed. Some studies, in fact, have shown that men taking testosterone have fewer heart problems. The link between testosterone therapy and prostate cancer is also murky.

What’s needed is a randomized, placebo-controlled trial, in which some men get testosterone and others get an inert substitute. In such a trial no one except some record keepers know who is getting what—not the volunteers or their doctors. If such a trial is done and it is large enough and lasts long enough, we should get clear answers on the benefits and risks of testosterone therapy. This wouldn’t come fast, or cheap. The Women’s Health Initiative, which tested in this way the benefits and risks of hormone therapy for women, took years and cost millions of dollars.

What to do today

Until such a trial is done, what’s a man to do in the face of such uncertainty? Take a cautious approach, advises the Harvard Men’s Health Watch:

• Take stock of your health first. There may be other reasons than your testosterone level for fatigue, a low sex drive, erectile dysfunction, and other symptoms attributable to low testosterone.
• Get an accurate assessment. If you or your doctor think you might have low testosterone, have it measured between 7 am and 10 am, when testosterone is at its daily peak. Then confirm the result with a second test on a different day.
• Be mindful of unknown risks. Ask your doctor to explain the various side effects for the different formulations of testosterone, such as gels, patches, and injections. Know what to look for if something goes wrong. And approach testosterone therapy with caution if you are at high risk for prostate cancer; have severe urinary symptoms from prostate enlargement; or have diagnosed heart disease, a previous heart attack, or multiple risk factors for heart problems.

Finally, “testosterone therapy is not a fountain of youth,” cautions the Men’s Health Watch. Don’t try it in hopes of channeling your more youthful physical or sexual self, of living longer or healthier, or of improving your memory or mental sharpness. Exercising more would be a safer—and probably more effective—approach for achieving those goals.