New study finds Ozempic and Mounjaro protect the heart too

• Large real-world study finds new GLP-1 drugs help protect the heart in people with cardiovascular risk.
• Clear evidence shows these medications support heart health beyond their weight-loss effects.
• Semaglutide (Ozempic) and tirzepatide (Mounjaro) offer similar levels of heart protection, with only small differences in results.

GLP-1 Drugs Linked to Better Heart Health

Injectable medications used for weight loss may also lower the risk of major cardiovascular problems in people with type 2 diabetes. Researchers from the Technical University of Munich (TUM) and Harvard Medical School reached this conclusion after analyzing insurance claims data. Their findings show that semaglutide and tirzepatide (sold as Ozempic and Mounjaro) can reduce the risk of serious heart-related events by as much as 18 percent.

The research, published in Nature Medicine, drew on a vast collection of data from U.S. health insurance records. "Those data are collected in routine clinical care and can be used for research. They allow us to answer a broad range of relevant questions efficiently. Importantly, we are studying patients who reflect everyday clinical practice -- unlike the highly selected participants typically enrolled in randomized trials," explains Dr. Nils Krüger, the study's lead author and a physician at the Department of Cardiovascular Diseases at the TUM University Hospital German Heart Center.

Heart Protection Beyond Weight Loss

The results clearly indicate that these newer diabetes treatments help protect the heart in people with elevated cardiovascular risk. Compared with sitagliptin, a diabetes medication known to provide no measurable heart benefits, semaglutide cut the risk of stroke and heart attack by 18 percent. Tirzepatide lowered the combined risk of stroke, heart attack, and death by 13 percent compared with dulaglutide, an older GLP-1 drug already in use.

"Both substances have a cardioprotective effect. Our data show that the benefits emerge from early on, indicating that the effect goes beyond weight loss alone," says Dr. Krüger. However, researchers note that the biological mechanisms behind this protective effect remain uncertain.

Because semaglutide and tirzepatide are relatively new, studies directly examining their cardiovascular effects have been limited, especially those comparing the two drugs head-to-head. The research team from TUM, Harvard Medical School, and Brigham and Women's Hospital aimed to fill this knowledge gap to guide better treatment decisions for patients at risk of heart disease.

Comparing Ozempic and Mounjaro

"According to the manufacturers' claims, each one suggests its own product is more effective than the competitor's at reducing cardiovascular risk," says Prof. Heribert Schunkert, Director of the Department of Cardiovascular Diseases at TUM University Hospital. "Our study, however, shows only small differences in heart outcomes between tirzepatide and semaglutide in the risk groups we analyzed."

Dr. Krüger adds: "We hope our findings will provide clarity to physicians about how these new medications perform in clinical practice. Our transparent study design is also intended to support open scientific discussion about whether and how modern GLP-1 drugs should become part of the standard therapeutic repertoire in cardiovascular medicine."

Recently, Dr. Krüger's team was able to show that treatment with semaglutide or tirzepatide can reduce health risks for people with heart failure with preserved ejection fraction by over 40 percent. The study has been published in the journal JAMA (PMID: 40886075).

This work was funded by the National Institutes of Health (R01-HL141505, R01-AR080194) and the German Heart Foundation (S/02/24, SRF-HF/24, RWE/11/25).