Over the past decade, ads touting testosterone therapy to treat low energy and a flagging libido in men have fueled a rapid rise in prescriptions for the hormone. Short-term studies suggest that testosterone therapy boosts bone mass, strength, and sexual function and improves some markers of heart disease risk. But concerns about the long-term safety of testosterone treatment (available as a gel, patch, or shot) linger, particularly after a 2010 study of testosterone in frail, older men was stopped early because of cardiovascular problems among the testosterone users.
Now, findings from a study of 8,700 male veterans with low testosterone add to the concern. Men who used testosterone therapy had a 30% higher risk of heart attack, stroke, or death over a three-year period than men who didn't use testosterone. The men, who were in their early 60s on average, had all undergone a heart imaging test, and most had risk factors for heart problems. Testosterone might boost heart risks by encouraging the formation of dangerous blood clots, say the authors, whose article appeared in The Journal of the American Medical Association.