November 5th, 2013
04:27 PM ET
It’s become the hot new treatment for older men. “T,” or testosterone replacement therapy, has been touted as the new way to turn back a man’s body clock and improve his sexual performance.
But there may be trouble in paradise, according to new research. In a study published this week in the Journal of the American Medical Association, scientists have found that men taking testosterone therapy had a 29% greater risk of death, heart attack and stroke than those who were not on the hormone replacement.
The study included 8,709 men with low testosterone levels, who underwent coronary angiography, a procedure used to open narrow or blocked coronary arteries, in the Veterans Affairs (VA) system between 2005 and 2011. Some were found not to have blockages.
Researchers found the number of patients experiencing heart problems such as attacks and strokes three years after their angiographies, was 19.9% for those who were not on testosterone and 25.7% for those who were. Even when scientists accounted for other factors in the patients’ health, the increase of heart events in those on testosterone therapy was significant, according to the study.
"These findings raise concerns about the potential safety of testosterone therapy," said Dr. Rebecca Vigen, lead author and an internist at the University of Texas Southwestern Medical Center in Dallas. "Future studies including randomized controlled trials are needed to properly characterize the potential risks of testosterone therapy in men with comorbidities (other conditions)."
But some doctors who looked at the study questioned the methods, saying many of these men already had heart issues.
“You need to be careful about the conclusion you draw from this study,” says Dr. Warren Levy, a cardiologist and director of Virginia Heart, based in Northern Virginia. “The study is of men who had undergone cardiac catheterization - so that already selects out a higher-risk population. The conclusion may be that for men with a higher risk of cardiovascular disease, testosterone therapy may increase risk slightly.”
So the question is, how does this affect men who are healthy? The male hormone replacement is so popular, prescriptions for the remedy reached 5.3 million a year in 2011 and are climbing, according to the study.
"Perhaps the most important question is the generalizability of the results of this study to the broader population of men taking testosterone: men of this age group who are taking testosterone for 'low T syndrome' or for anti-aging purpose,s and younger men taking it for physical enhancement," Dr. Anne R. Cappola, an associate professor of medicine in the Division of Endocrinology, Diabetes, and Metabolism with the Perelman School of Medicine at the University of Pennsylvania and a contributing editor for the Journal of the American Medical Association, writes in an accompanying editorial.
"In light of the high volume of prescriptions and aggressive marketing by testosterone manufacturers, prescribers and patients should be wary,“ says Cappola. “ We are just beginning to see the effects of hormone replacement therapy in men. In women, we have data from decades of research. But for men, we are still sort of in the dark.”
Even when the men had a clean bill of health after no blockage was found when coronary angiographies were performed, they still had a high rate of heart problems if they were on testosterone therapy, Cappola points out. As to why testosterone effects the heart, scientists still don't understand the connection, but it has been shown the hormone can lower a patient's HDL, or good cholesterol. Yet doctors think it's more than that.
So what’s the takeaway message for those who are toying with the idea of testosterone therapy? Study authors recommend men talk to their doctors about the hormone replacement and how it fits into their general health profile and should be cautious of it if they have a history of heart problems.
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