More research finds GLP-1s can protect the heart

A real-world analysis of 52,971 American adults living with both type 2 diabetes and established atherosclerotic cardiovascular disease and who were either taking tirzepatide - known as the brand Mounjaro - or sitagliptin as a placebo proxy found that, after one year, 2.9 percent of them who were on tirzepatide had experienced a major cardiovascular event compared with 4.4 percent of the group who took the placebo.

This amounts to a roughly 32 percent lower risk. Put in practical terms, treating about 70 people with tirzepatide instead of sitagliptin prevented one additional major cardiovascular event.

Tirzepatide was linked to a lower risk of heart attack, but researchers found no clear difference in ischemic stroke between the two groups. There was also an unexpected finding outside the cardiovascular lane: fewer infections requiring hospital treatment, fewer deaths from infection, and fewer deaths overall.

Checks against unrelated health conditions turned up no meaningful associations, which strengthens the case that the results aren't simply an artifact of healthier patients choosing the newer drug.

Two tirzepatide studies presented at the SCAI 2026 Scientific Sessions in Montreal in April pointed in the same direction for patients undergoing cardiac procedures. Researchers reported a 30 percent lower risk of major heart problems, including stroke, among people with obesity who had a transcatheter aortic valve replacement, and a 62 percent lower mortality risk in people with type 2 diabetes undergoing percutaneous coronary intervention compared with dulaglutide.

Separate work published in the Journal of the American Heart Association in June found GLP-1 use associated with fewer clotting events in adults with obesity and autoimmune disease. This translates into a 31 percent lower risk of pulmonary embolism, a 17 percent lower risk of venous thromboembolism, a 21 percent lower number of emergency department visits, and a 44 percent lower all-cause mortality.

A March study in BMJ Medicine followed 132,551 people on GLP-1s against 201,136 on sulfonylureas over three years. Cardiovascular benefit grew with duration of use, but 26.36 percent of patients discontinued, most often within the first year, and stopping appeared to reduce or reverse the protection.

"GLP-1 therapy behaves more like a long-term risk-reduction treatment than a short-term fix," said Dr. Robert Glatter of Lenox Hill Hospital in New York City, speaking to Healthline. "Benefits that accumulate slowly can be lost surprisingly fast when treatment is interrupted."