Updated on September 19, 2022.
Testosterone (T) therapy is often prescribed to treat low libido and erectile dysfunction, and to increase strength. The problem is, it’s long been dogged by concerns about side effects and health risks—and studies regarding its safety have reached differing conclusions.
Some studies have linked T therapy to increased chances of heart attack and stroke. Other research suggests that they’re not directly related. Because of the possible risk, however, the U.S. Food and Drug Administration (FDA) states that T therapy should be taken with caution, particularly among adults.
Why the confusion?
In 2013, two key studies raised the possibility of risks related to T therapy. The first, published in The Journal of the American Medical Association in 2013, found that U.S. veterans who received testosterone therapy had a higher risk of heart attack, stroke, and death.
The second study, published in 2014 in PLOS One, found that the risk of heart attack and stroke doubled in the first 90 days after T therapy in older men. In younger men with pre-existing heart disease, the risk tripled in the first 90 days of use.
Shortly thereafter, the FDA revised its guidelines around T therapy, advising caution for older people with cardiovascular risk.
But since then, other research has suggested that T therapy may not be a heart threat. In 2021, a study of more than 200,000 men aged 40 years and older published in the Journal of the American Heart Association showed that treatment with testosterone wasn’t associated with higher risk for heart attack or stroke, whether they had existing cardiovascular disease or not.
Does having low testosterone levels affect heart risk?
Interestingly, there have also been ties between low testosterone levels and heart risk.
In a review published in the Journal of Clinical Endocrinology & Metabolism in 2013, researchers evaluated studies dating back to 1970 that dealt with the relationship between testosterone and cardiovascular disease in men. They concluded that men with low T had a slightly higher risk of developing or dying from heart disease. But the finding came with caveats. Low T was not directly linked with arteriosclerosis (hardening of the arteries), nor did it show that low levels directly increased risk of heart attack. Researchers also found that treating low T with testosterone replacement had no effect on improving men’s heart health.
Some research has found that women may be affected by low testosterone, as well. A commentary published in 2022 in The Lancet concluded that it may increase the risk for heart disease, stroke, and heart attack in women older than 70.
Meanwhile, a study published in 2021 in European Heart Journal drew different conclusions about low T. Researchers found that in men with hypogonadism (when sex glands don’t produce much testosterone), long-term T therapy was linked to fewer cardiovascular events, such as stroke and heart attack, as well as reduced mortality.
Determine if T therapy is right for you
Experts are still trying to understand the exact risks involved with taking testosterone therapy, and there might not be a clear-cut answer for the time being.
People considering T therapy should discuss all concerns with their HCPs. Even more importantly, HCPs and patients should think about whether the benefits of testosterone treatment outweigh the associated risks. This consideration may change from individual to individual based on factors such as age and previous heart history. The FDA has also asked HCPs who prescribe testosterone treatment—and the people who take it—to report any adverse effects to its MedWatch program.
