Where the Concern Came From
In the early 2010s, a few studies suggested testosterone therapy might increase the risk of heart attacks and strokes. These studies had limitations, but they led the FDA to require warnings about possible cardiovascular risk and called for a large, high-quality trial.
What the TRAVERSE Trial Found
That trial, called TRAVERSE, was published in 2023 in the New England Journal of Medicine. It included more than 5,000 men aged 45 to 80 with low testosterone and either existing heart disease or a high risk of it.
The key finding: testosterone therapy did not increase the risk of major adverse cardiovascular events—heart attack, stroke, or cardiovascular death—compared with placebo.
Other Findings Worth Knowing
TRAVERSE did find slightly higher rates of:
- Atrial fibrillation (an irregular heart rhythm)
- Pulmonary embolism (blood clots in the lungs)
- Acute kidney injury
In 2025, the FDA updated testosterone labels to reflect TRAVERSE's findings and added warnings about potential increases in blood pressure.
How to Protect Your Heart on TRT
- Get a baseline evaluation: Blood pressure, cholesterol, blood sugar, and heart history
- Monitor hematocrit: Too many red blood cells can thicken the blood
- Check blood pressure regularly
- Keep testosterone in a normal range: Avoid excessive doses
- Treat sleep apnea if present
- Stay active and maintain healthy habits
Low Testosterone and Heart Health
Low testosterone itself is associated with higher rates of obesity, diabetes, and metabolic syndrome—all of which affect heart health. Addressing these through lifestyle changes is important whether or not you use TRT.
Learn more about provider-guided testosterone therapy here: Heva Hormone Optimization
The Bottom Line
The best current evidence shows that properly monitored TRT does not increase heart attack or stroke risk in men with low testosterone. Regular monitoring of blood pressure and hematocrit helps keep treatment safe.