Testosterone therapy increased heart rhythm problems in men with low testosterone
Compared with placebo, testosterone replacement increased heart rhythm disorders in trials of men with low testosterone. Differences in deaths, strokes and heart attacks remained statistically uncertain.
Based on the published abstract. The full paper may contain additional methods, results and limitations.
The 30-second takeaway
For men in these trials, testosterone replacement increased reported heart rhythm disorders compared with placebo. The analysis did not detect statistically significant differences in overall deaths, cardiovascular deaths, strokes or heart attacks. Those uncertain results do not establish equal safety, and the rhythm finding should remain part of the overall interpretation.
The abstract does not provide absolute event rates or describe which rhythm disorders occurred. It therefore cannot show how many additional men experienced an arrhythmia or how serious those events were.
What researchers found
Incidence of cardiac arrhythmias
Testosterone versus placebo over at least 12 months: risk ratio 1.53 (95% confidence interval 1.20–1.97). This compares event risks, not absolute numbers affected.
What the main result means
An arrhythmia is a heart rhythm disorder. The pooled risk ratio compared its occurrence between treatment groups. Its confidence interval stayed above the value indicating equal risk, supporting the reported increase while leaving its precise size uncertain.
Why the other results remain uncertain
For deaths, strokes and heart attacks, the statistical ranges included equal risk. The trials therefore did not clearly distinguish the groups for those outcomes. This differs from demonstrating that testosterone and placebo have identical risks.
The original publication
Long-Term Cardiovascular Safety of Testosterone-Replacement Therapy in Middle-Aged and Older Men: A Meta-analysis of Randomized Controlled Trials.
Braga MAP, Rivera A, Marinheiro G et al.
Am J Cardiovasc Drugs · 2025
- PubMed ID
- 40694252
- Record checked
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