The therapy has come under widespread scrutiny in recent months, including by a federal Food and Drug Administration panel convened last fall. But the latest research indicates such concerns are misplaced and unwarranted. In fact, the findings suggest low levels of the male hormone may increase the risk for heart disease.
 

"There's no good evidence that we could find that testosterone therapy increases cardiovascular risk," says lead researcher Abraham Morgentaler, M.D., director of Men's Health Boston and a urologist on staff at Beth Israel Deaconess Medical Center. "That's not to say it's perfectly safe. But we cannot find evidence and the headlines that jumped out on recent retrospective studies appear to be too strong."
 

He added that the new review of studies "clearly reveals a strong relationship between higher serum testosterone concentrations ... as being beneficial for reduction in cardiovascular disease and cardiovascular risk factors."
 

Testosterone levels generally begin a gradual decline after the age of 30, a drop that may be accompanied by a decrease in sex drive. In recent years, the use of testosterone replacement therapy has increased substantially, aided in part by "patient-friendly formulations" such as topical gels that are widely advertised on television.
 

Such advertisements, combined with two recent studies raising questions about cardiovascular risk associated with the treatment, moved the FDA to convene an advisory panel to study the safety of testosterone therapy last year.
 

But Dr. Morgentaler and colleagues tracked studies conducted since 1940 on low-T and found only four published scientific journal articles suggested increased cardiovascular risks with testosterone prescriptions. Two of those four articles, which generated substantial media coverage over the last 15 months, had "serious methodological limitations,” they found.
 

What’s more, they found dozens of studies identified a link between "low testosterone levels and increased mortality ... as well as atherosclerosis, incident coronary artery disease and the severity of coronary artery disease."
 

"Testosterone has been presented as if there were a debate about whether it is good or evil," said Dr. Morgentaler. "Rather, it is a long-accepted medical treatment for a medical condition recognized for centuries.
 

“Our intention was to cut through the confusion of loudly expressed opinions on non-scientific issues — such as pharmaceutical advertising, anti-aging claims, and the importance of sexuality in older men — to provide the most comprehensive review to date of the literature on testosterone and cardiovascular risk."