A new, independent, preliminary study presented at the American Heart Association’s Scientific Sessions 2026 suggests that GLP-1 medications, widely known for weight loss, may be more effective than metformin at preventing Type 2 diabetes and reducing cardiovascular risks in adults with prediabetes and obesity. The research, which reviewed health records for more than 250,000 adults, is among the largest to compare these two treatment approaches and could influence how clinicians consider early intervention for a condition affecting nearly 40% of U.S. adults, according to the Association’s 2026 Heart Disease and Stroke Statistics.
The study analyzed electronic health records from the TriNetX global network, including 256,492 adults with prediabetes and obesity (average age 52, 76% women) treated between 2010 and 2023. Approximately half were taking GLP-1 receptor agonists such as semaglutide, tirzepatide, liraglutide, or dulaglutide, while the other half were taking metformin, the long-standing first-line medication for blood sugar management. After matching patients for age, health conditions, and other medications, researchers found that those on GLP-1s had a 1.5 times higher chance of reversing high blood sugar to normal levels, a 31% lower risk of developing Type 2 diabetes, and a 41% lower risk of death from any cause over an average follow-up of roughly three years.
Cardiovascular outcomes also favored GLP-1 medications: the study reported 15% fewer heart attacks, 20% fewer strokes, 25% fewer cases of heart failure, and 8% fewer cases of atrial fibrillation compared with metformin. “The great news with prediabetes is that it’s still possible to reverse the progression of the disease,” said study author Vinicius de Sousa Barzon Serra, M.D., a research fellow in cardiovascular medicine at the Mayo Clinic in Scottsdale, Arizona. “This research may add to the case for considering GLP-1 medications earlier for certain patients, rather than waiting until they develop Type 2 diabetes.”
However, Serra emphasized that metformin remains a safe, inexpensive, and well-established first-line option, and that the findings are more about expanding shared decision-making than replacing one drug with another. Robert Eckel, M.D., FAHA, a past volunteer president of the American Heart Association who was not involved in the study, noted that the benefits likely stem from weight loss, which is known to help prevent Type 2 diabetes and its cardiovascular complications. He cautioned that costs and access to GLP-1 medications are important factors. The study is observational and cannot prove cause and effect; it also relied on diagnosis codes and prescription records, which may be incomplete, and did not differentiate among individual GLP-1 agents. The findings are considered preliminary until published in a peer-reviewed journal, and full details are available in the abstract and the Online Program Planner for Scientific Sessions 2026.
The implications are significant for clinical practice and public health: with prediabetes affecting such a large share of the population, identifying effective strategies to reverse or delay progression could reduce the burden of diabetes and cardiovascular disease. The study adds to a growing body of research on GLP-1 medications, including prior findings that healthy lifestyle combined with newer diabetes medications lowered cardiovascular risk and that new weight loss medication may help lower blood pressure in adults with obesity. As the conversation around early intervention evolves, the American Heart Association continues to provide resources on related topics, including prediabetes linked to higher heart attack risk in young adults and a new guideline reframes weight as health risk tied to diabetes, kidney and heart conditions. For more information, visit heart.org or stroke.org.
