Men who take testosterone to boost low levels of the hormone may be putting their heart health at risk, a study published in The Journal of the American Medical Association suggests.
The research found that older men who took testosterone after being tested for signs of coronary artery disease (CAD) were more likely to have a heart attack or stroke or to die of any cause over the next three years compared to men not taking the hormone. The 29 percent increase in risk was the same whether the men did or did not have CAD.
“These findings raise concerns about the potential safety of testosterone therapy,” the authors wrote.
And, although the study involved men with a history of health problems, an editorial accompanying the study suggested that all men should be wary of jumping on the “low T” bandwagon.
The evidence “is mounting” that testosterone therapy raises the risk for CAD, Anne R. Cappola, MD, of the Perelman School of Medicine, wrote in the editorial.
Testosterone use has increased significantly in recent years, with 5.3 million prescriptions worth $1.6 billion filled in 2011 alone, according to background information in the study. Marketing campaigns tout benefits like improved sexual function, muscle strength and general well-being, but the evidence of risks and benefits is limited, the editorial noted.
Also unclear is whether testosterone therapy is safe for older men. The authors of the current study pointed to a previous testosterone trial of older, frail men with CAD that ended early when 23 people had heart attacks, strokes or other major problems.
About the study
Researchers used a retrospective analysis (looking backward at events that already occurred) to find 8,709 male veterans with clinically low testosterone levels who underwent coronary angiography testing between 2005 and 2011. The men were, on average, in their early 60s. Most also had significant health problems, including past heart attacks, diabetes and CAD.
Within a median 531 days after angiography, 1,223 men began testosterone therapy; 7,486 did not.
Using Veterans Affairs records, researchers followed the men for three years, looking for heart attack, ischemic stroke (stroke due to blocked arteries) and death from any cause.
Among the findings:
- In total, there were 748 deaths, 443 heart attacks and 519 strokes.
- Among the 1,223 men on testosterone, 67 died, 23 had heart attacks and 33 had strokes.
- Among the 7,486 not on testosterone, 681 died, 420 had heart attacks and 519 had strokes.
- The likelihood of those on testosterone having a heart attack or stroke or dying was 29 percent higher than the men not taking testosterone.
- That 29 percent higher risk did not differ for men with or without CAD.
- The risk also didn’t differ between men who were being treated for high blood pressure and other conditions compared to those who were not.
|The take-home message|
|The research doesn’t prove that testosterone therapy causes cardiovascular problems. The study was observational (the researchers only looked at existing data), and it’s possible that other factors might have influenced the results.
The authors noted several possible ways in which testosterone might increase cardiovascular risks, including some evidence that it could play indirect roles in the hardening and narrowing of arteries over time.
Clinical trials that compared testosterone therapy with a placebo would yield more information, the authors wrote.
Men who are considering testosterone therapy are urged to talk with their doctors about the potential risks and benefits.