Testosterone, the hormone most responsible for “maleness” in men, naturally declines with age. Drug companies have capitalized on this fact, and on the vague symptoms that make up the non-medical, popular term “andropause.” Supposedly, low or even low-ish testosterone levels can make men feel bad—really, really bad. Symptoms attributed to this putative condition range from sexual dysfunction, to fatigue, mood changes, and irritability. Unfortunately, all of these symptoms are common and vague, making it difficult to find out if low testosterone is responsible for the symptoms.
This uncertainty doesn't diminish the popularity of prescription testosterone. Sales in the U.S. top $2 billion yearly. Men often report feeling better when taking the male hormone, and clinics are popping up catering to “anti-aging” therapy which often includes testosterone therapy.
Because of the uncertainties of efficacy, testosterone replacement in men is medically controversial. Companies advertising treatment for “Low T” are often accused of disease mongering. The drug's safety is also uncertain.
A study published in the New England Journal of Medicine in 2010 concluded that testosterone treatment increased the risk of cardiovascular events such as stroke and heart attacks. The effect was serious enough that the study was halted early.
Unfortunately, the paper focused on older men with a variety of health problems, leaving the question of whether hormone treatment might be safer in healthier men.
A study released this month in the Journal of the American Medical Association tried to answer some of the lingering questions about treatment. Rather than looking at rates of heart attack and stroke, they monitored the thickness of the carotid arteries and the presence of calcium in heart arteries. These are often seen as “stand-in” measures for the risk of heart attack and stroke.
The authors did not see any significant progression of vascular disease. They also failed to see any improvement in quality of life.
Both of these studies have significant limitations, but taken with the rest of the relevant medical literature, there seems to a small but significant risk of testosterone therapy in some patients, and there seems to be little benefit.
Testosterone replacement therapy certainly has its place in modern medicine, especially in people with certain types of hormone problems. Its growing use suggests, though, that it is used much more than the evidence of safety and efficacy would justify.
Peter A. Lipson, ACP Member, is a practicing internist and teaching physician in Southeast Michigan. After graduating from Rush Medical College in Chicago, he completed his internal medicine residency at Northwestern Memorial Hospital. This post first appeared at his blog at Forbes. His blog, which has been around in various forms since 2007, offers "musings on the intersection of science, medicine, and culture." His writing focuses on the difference between science-based medicine and "everything else," but also speaks to the day-to-day practice of medicine, fatherhood, and whatever else migrates from his head to his keyboard.