Cedars-Sinai Blog
Research Finds Testosterone Therapy Safe for Heart Health
In middle age, men’s testosterone levels often drop. Sometimes, low testosterone levels don’t cause symptoms, but the decrease can lead to reduced libido, erectile dysfunction, cardiovascular disease, obesity or depression.
Men with symptoms of low testosterone may seek treatment, such as testosterone replacement therapy. For years, physicians debated testosterone replacement therapy’s impact on cardiovascular health. Now, new research has confirmed testosterone replacement therapy doesn’t increase the risk of heart attack or stroke.
“When patients have symptoms of low testosterone, physicians can feel more comfortable that prescribing testosterone supplements to maintain normal physiologic levels does not come with a significant liability,” said cardiologist Prediman K. Shah, MD, director of the Cedars-Sinai Atherosclerosis Prevention and Management Center.
Prediman K. Shah, MD
New Research Confirms Testosterone Replacement Safety
A landmark study, published in 2023, tracked more than 5,200 men between the ages of 45 and 80 who had low testosterone levels. The findings, published in the New England Journal of Medicine, showed testosterone replacement therapy did not increase the risk of heart attack or stroke, compared to placebo.
“That’s reassuring, because in the past, physicians have been concerned about testosterone supplements increasing red blood cell count, leading to blood clots and increased heart attack risk,” Shah said.
Previous research in testosterone replacement therapy and cardiovascular risk had mixed results.
“Now, physicians can feel assured about their recommendations for patients with low testosterone levels."
“Some studies showed possible benefits, while others showed possible risks, which was confusing for patients, as well as physicians trying to advise patients,” said Howard Kim, MD, a Cedars-Sinai urologist. “Now, physicians can feel assured about their recommendations for patients with low testosterone levels.”
The research did find a slight increase in atrial fibrillation risk among men who received testosterone therapy. Arash Nayeri, MD, a Cedars-Sinai cardiologist, says patients who are concerned about the risk should discuss it with their doctor.
“No therapy is 100 percent safe, and the risk profile is pretty similar to most other medications we take, even in high-risk cardiovascular patients,” said Nayeri.
However, the research has not addressed the safety of testosterone replacement therapy in men older than 80 or younger than 45.
“Testosterone therapy isn’t for younger men seeking to boost athletic endeavors or men without a documented low-testosterone evaluation,” Kim said.
Howard H. Kim, MD
Testosterone Therapy May Improve Quality of Life
Primary care physicians, urologists and endocrinologists can prescribe testosterone replacement therapy. These physicians typically consult with a patient’s cardiologist (if they have one) about the risks and benefits of testosterone replacement therapy for each patient individually. Once patients begin testosterone replacement therapy, physicians regularly track their cholesterol levels and prostate health, in addition to their testosterone levels.
Many physicians prescribe testosterone to patients in the form of topical gel, transdermal patches, pills or injections.
“Often, topical gel therapy is the easiest to try, because it’s not invasive,” Kim said. “It provides a gentle boost to testosterone levels, instead of the big swings you might get with injection therapy.”
Symptoms of low testosterone such as erectile dysfunction or decreased libido can be awkward to discuss. But having these uncomfortable conversations with your primary care doctor or urologist may help you learn whether you have low testosterone levels. If you do—and you’re close to, or between, ages 45 and 80—you may be a candidate for testosterone replacement therapy.
“You need to advocate for yourself in your doctor’s office,” Nayeri said. “Unless you bring this up, chances are your doctor won't.”
The 2023 study only tracked the effects of testosterone replacement therapy for a few years, so more research is needed to confirm long-term safety.
“We still don’t know for sure if testosterone supplements are completely safe for lifelong use,” said Shah. “More research is needed, even though the results of the published study are reassuring.”
Arash Nayeri, MD
