The weight-loss drugs reshaping medicine may have a second act: preventing diabetes itself, and doing it better than the standard treatment, according to data due at this weekend’s American Heart Association meeting.
Key Points
- In a study of more than 256,000 adults with prediabetes and obesity, GLP-1 drugs outperformed metformin over three years, Reuters reported.
- Patients on GLP-1s had a 50% higher chance of reversing high blood sugar to normal levels and a 31% lower risk of developing type 2 diabetes.
- They also had a 41% lower risk of death from any cause, 15% fewer heart attacks, 20% fewer strokes and 25% fewer cases of heart failure than metformin patients.
- The study leader was Dr Vinicius de Sousa Barzon Serra of the Mayo Clinic in Scottsdale, Arizona.
A large, real-world comparison
The study’s size is its strength. Researchers reviewed medical records of more than 256,000 adults with prediabetes and obesity, about half taking a GLP-1 medication — semaglutide, tirzepatide, liraglutide or dulaglutide — and half taking metformin, the long-standing first-line drug. Over three years, the GLP-1 group did better on almost every measure that matters: blood sugar, progression to diabetes, heart attacks, strokes, heart failure and death.
The 41% lower risk of death from any cause is the eye-catching figure, but the heart numbers may matter more for clinicians: 15% fewer heart attacks, 20% fewer strokes, 25% fewer heart failure cases and 8% fewer cases of atrial fibrillation, the irregular heartbeat that can raise stroke risk fivefold.
Caveats that must stay attached
This is, for now, an abstract — a summary of a study to be presented in detail at the American Heart Association meeting — not a peer-reviewed paper, and it is based on medical records rather than a randomised trial. That design can show associations, not prove causation, and patients prescribed GLP-1s may differ from those given metformin in ways records do not fully capture.
Cost and access are the other caveats. GLP-1 drugs are far more expensive than metformin, and supply and side effects remain live questions. A result this strong will fuel calls to widen access — and will also fuel the argument about who pays.
The findings also sit alongside other AHA data reported on Wednesday, including studies on hormone therapy and heart health and on cannabis and cardiovascular risk. Together they underline a theme of this year’s meeting: that familiar, widely used treatments are being re-examined with much larger datasets — and sometimes found wanting.
What happens next
The full presentation in Chicago will be scrutinised for exactly those details: how the groups were matched, what doses were used, and whether the benefits held across age, weight and risk groups. If they hold, guidelines for prediabetes — a condition affecting millions who never progress to diabetes — could start to shift.
Sources
- Reuters Health Rounds via 941 The Duke — https://941theduke.com/2026/11/04/glp-1-drugs-help-control-prediabetes-better-than-current-standard-medicine/