TRT and heart health research has shifted. The large 2023 TRAVERSE trial found no increase in major heart events versus placebo in high-risk men, though atrial fibrillation rose. TelosRX providers review cardiovascular history before approval.
For about a decade, testosterone came with a heart-shaped asterisk. Headlines warned of heart attacks and strokes. Then bigger, better trials arrived.
This review walks through what the research on TRT and heart health actually found, study by study. No hype, and no promises. Just the evidence and its limits.
Why TRT and Heart Health Became a Concern
Testosterone therapy (TRT) is FDA-approved for men with hypogonadism (low testosterone from a diagnosed medical cause). Use climbed sharply in the early 2010s. So did questions about safety.
Two things drove the worry. A small trial was stopped early for heart-related events. Then several observational studies reported mixed signals. In 2015, the FDA added cardiovascular risk language to testosterone labeling.
Timeline of Key TRT Heart Studies
| Year | Study / action | Who was studied | Main heart finding |
|---|---|---|---|
| 2010 | TOM trial (NEJM) | 209 older men with limited mobility | More cardiovascular-related adverse events with testosterone; stopped early |
| 2015 | FDA labeling update | All testosterone products | Added possible heart attack and stroke risk language |
| 2022 | Individual-patient meta-analysis (Lancet Healthy Longevity) | 35 trials, 5,601 men | No significant difference in cardiovascular events vs placebo |
| 2023 | TRAVERSE trial (NEJM) | 5,246 men aged 45–80 at high cardiovascular risk | Major heart events 7.0% vs 7.3% placebo; more atrial fibrillation |
| 2025 | FDA class-wide labeling change | All testosterone products | Removed boxed-warning heart-outcome language; added blood pressure warnings |
Finding 1: The Early Warning Signal (2010)
The Testosterone in Older Men with Mobility Limitations (TOM) trial enrolled 209 men (Basaria et al., New England Journal of Medicine, 2010). Their average age was 74. Many had high blood pressure, diabetes, or obesity.
The trial stopped early. Twenty-three men on testosterone had cardiovascular-related adverse events, compared with five on placebo. Strength and stair-climbing did improve in the testosterone group.
The catch: it was small, short, and not designed to measure heart outcomes. Still, it rightly raised a flag.
Finding 2: Pooled Trial Data Look Reassuring (2022)
A large individual-patient and aggregate data meta-analysis pooled 35 randomized trials with 5,601 men. Researchers analyzed raw participant data where available.
- Cardiovascular events: 7.5% with testosterone vs 7.2% with placebo
- Odds ratio 1.07, not statistically significant
- Age, baseline testosterone, and smoking didn't change the result
The authors were careful. They found no evidence of short- to medium-term heart risk. But they noted a shortage of long-term safety data.
Finding 3: TRAVERSE, the Trial Built to Answer the Question (2023)
The FDA asked manufacturers for a dedicated safety trial. That became TRAVERSE, published in the New England Journal of Medicine.
It enrolled 5,246 men aged 45 to 80. All had symptoms of low testosterone, levels under 300 ng/dL, and existing heart disease or high cardiovascular risk. Men applied a daily testosterone gel or placebo gel.
What TRAVERSE found
- Major adverse cardiac events: 7.0% testosterone vs 7.3% placebo (hazard ratio 0.96)
- Testosterone met the trial's goal of non-inferiority, meaning it was not worse than placebo
- Atrial fibrillation (an irregular heart rhythm), acute kidney injury, and pulmonary embolism (a lung blood clot) occurred more often with testosterone
So the headline is mixed. Heart attacks and strokes didn't rise. Some other events did.
Wondering if testosterone support is right for you? Start with TelosRX men's health. Any prescription is subject to medical approval by a licensed provider after a full health review.
Finding 4: The FDA Updates Labeling (2025)
In February 2025, the FDA announced class-wide labeling changes for testosterone products. The agency reviewed TRAVERSE alongside ambulatory blood pressure studies.
- TRAVERSE results are added to all testosterone labeling
- Boxed-warning language about increased adverse cardiovascular outcomes is removed
- A warning about increased blood pressure is added across products
- The limitation on use for age-related low testosterone stays in place
Blood pressure is now the cardiovascular measure the label calls out most clearly. That's why monitoring matters.
What the Research Doesn't Tell Us Yet
Good evidence still has edges. Here's where the TRT and heart health data run thin.
- Long-term use: In TRAVERSE, average treatment lasted about 22 months. Decades of use aren't studied.
- Younger men: Most data come from men over 45 with existing risk.
- Injections vs gel: TRAVERSE used a daily gel. Injections create different hormone peaks and troughs.
- Men without true hypogonadism: These results don't apply to normal-testosterone men using it for performance.
Compounded testosterone formulations are not FDA-approved. They weren't the products tested in TRAVERSE.
How to Read TRT Heart Headlines
Testosterone news tends to swing between "dangerous" and "totally safe." The research supports neither extreme. A few questions help you sort a headline fast.
- Was it randomized? Observational studies can show links, but not cause and effect.
- Who was studied? Results in frail 74-year-olds may not apply to healthy 50-year-olds.
- Which outcome? "Heart events" can mean heart attacks, rhythm problems, or blood pressure changes.
- Relative or absolute risk? A big percentage change can still mean few extra cases.
TRAVERSE scores well on these questions. That's why it carries more weight than earlier, smaller studies.
What Monitoring Looks Like in Practice
Because of these findings, providers typically track a few markers before and during therapy.
- Blood pressure — at baseline and periodically
- Hematocrit (the share of blood made of red cells) — testosterone can raise it
- Heart rhythm symptoms — palpitations or a racing, irregular pulse
- Testosterone levels — to confirm they stay in a target range
- PSA and lipids — as part of routine follow-up
Want the bigger picture on side effects? See TRT side effects, answered. Not sure your levels are low? Start with signs of low testosterone in men.
How TelosRX Approaches TRT and Heart Health
TelosRX is an asynchronous telehealth service. You complete your intake, including heart history, blood pressure, and labs, on your own schedule. A licensed provider reviews everything before any decision.
Men with recent heart events, uncontrolled blood pressure, or certain rhythm problems may not be candidates. If you're approved, you can message your care team anytime about new symptoms. Learn how free testosterone fits into lab review.
Frequently Asked Questions
Does TRT increase the risk of heart attack?
The largest trial to date, TRAVERSE, found major adverse cardiac events in 7.0% of men on testosterone versus 7.3% on placebo. That's no meaningful increase. The trial included men aged 45 to 80 with existing heart disease or high risk. It did not study very long-term use or younger men.
Is TRT safe for men with heart disease?
TRAVERSE specifically enrolled men with existing or high cardiovascular risk and found no increase in heart attacks or strokes. It did find more atrial fibrillation, kidney injury, and lung clots. Whether TRT suits you depends on your specific history. Approval is subject to medical approval by a licensed provider.
Can testosterone therapy cause atrial fibrillation?
In TRAVERSE, atrial fibrillation was more common in the testosterone group than the placebo group. The reason isn't fully understood. If you notice palpitations, a racing pulse, or an irregular heartbeat while on therapy, contact your provider promptly. Seek emergency care for chest pain or fainting.
Does TRT raise blood pressure?
It can in some men. In 2025, the FDA added a class-wide warning about increased blood pressure to testosterone labeling, based on ambulatory blood pressure studies. Providers typically check blood pressure before starting and periodically during therapy. Uncontrolled hypertension may need to be addressed first.
Did the FDA remove the heart warning from testosterone?
In February 2025, the FDA directed labeling changes that remove boxed-warning language about increased adverse cardiovascular outcomes. TRAVERSE results were added to labeling. At the same time, the agency added or strengthened warnings about increased blood pressure. So heart-related monitoring still matters.
Is TRT good for heart health?
Current evidence doesn't show TRT protects the heart. The strongest data show it was not worse than placebo for major heart events in high-risk men. Some studies suggest links between low testosterone and cardiometabolic risk, but that's association, not proof. TRT is prescribed for diagnosed hypogonadism, not for heart benefit.
TelosRX is LegitScript-certified. Compounded medications are not FDA-approved and are prepared under federal compounding regulations. Approval is subject to evaluation by a licensed provider; approval is not guaranteed. Individual results vary. TelosRX operates as an online-first, asynchronous telehealth service.
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