GLP-1 drugs vs metformin: 31% lower diabetes rate in prediabetes and obesity, observational study

An observational study of 256,492 adults with both prediabetes and obesity compared GLP-1-based drugs with metformin, lomazoma.com reports. After three years of follow-up, the diabetes rate in the GLP-1 group was 31% lower than in the metformin group, and all-cause mortality was 41% lower lomazoma.comlomazoma.comlomazoma.comOpen source ↗. The results are expected to be presented at the American Heart Association Scientific Sessions 2026 in Chicago and have not yet been fully peer-reviewed.

Metformin is commonly named in guidelines as the first-line drug for type 2 diabetes and is sometimes used to slow progression from prediabetes. GLP-1 receptor agonists, including semaglutide, tirzepatide, liraglutide and dulaglutide, act on metabolism through several mechanisms, among them reduced appetite and, typically, greater weight loss.

Cardiovascular outcomes

According to the report, the GLP-1 arm had 20% fewer strokes, 15% fewer heart attacks and 25% fewer cases of heart failure than the comparison group lomazoma.comlomazoma.comlomazoma.comOpen source ↗. Earlier analyses mostly focused on people who already had type 2 diabetes; this study looks at the transition from the prediabetes stage.

Limitations of the data

The authors note that observational studies cannot establish causality. Groups were matched by age, health status and other characteristics, but differences between them could be only partly balanced, not excluded lomazoma.comlomazoma.comlomazoma.comOpen source ↗. The analysis pooled GLP-1 drugs, so it is unclear whether individual agents differ in effect relative to metformin. Electronic health records may be incomplete or contain errors, and dosage and adherence may have influenced the results. The findings should be treated as preliminary until published in a peer-reviewed journal.

People from the authors' circle advise that patients with prediabetes and obesity discuss options with their physician and not stop or change medication on their own. Metformin is described as a safe, relatively inexpensive drug with long clinical use, and lifestyle measures remain the foundation: diet, regular physical activity and weight management lomazoma.comlomazoma.comlomazoma.comOpen source ↗.