Weight-loss drugs tied to reduced diabetes and cardiovascular risk

Medications commonly prescribed for weight loss were associated with a lower chance of developing type 2 diabetes than metformin in a large study based on health records.

People who used the newer drugs also recorded fewer heart attacks, strokes and diagnoses of heart failure.

The study examined 256,492 adults with obesity and prediabetes, a condition in which blood sugar is above normal but still below the diabetes range. Researchers looked for differences in outcomes before participants developed full type 2 diabetes.

These early findings are set to be presented at the American Heart Association’s Scientific Sessions. The work is observational, so it cannot prove the newer medicines caused better results or show that all people with prediabetes should take them.

Researchers compared patients prescribed metformin with those given GLP-1-based medicines, a class of drugs tied to blood sugar control and appetite. The newer group included semaglutide, liraglutide, dulaglutide and tirzepatide.

Metformin is a long-established, relatively low-cost diabetes medicine that is also used for some people at high risk of developing diabetes. The research evaluated an additional treatment option rather than questioning whether metformin remains useful.

The records came from 104 institutions in a large electronic health record network spanning 2010 to 2023. Participants were about 52 years old on average, 76% were women, and the average follow-up period was roughly three years.

Treatment choices also need to account for body composition, including research on muscle loss during treatment with weight-loss medicines.

The team matched participants with similar measured traits, including age, health conditions and other medications. That made the groups more comparable, although it could not eliminate every difference that might affect treatment decisions or later health.

Compared with metformin, GLP-1-based treatment was linked with about 1.5 times the likelihood of blood sugar returning to normal. It was also associated with a 31% lower risk of type 2 diabetes and a 41% lower risk of death from any cause.

The newer-drug group had 15% fewer heart attacks, 20% fewer strokes and 25% fewer cases of heart failure. Atrial fibrillation, an irregular rhythm involving the heart’s upper chambers, was about 8% less common.

These are relative differences rather than the share of all patients who avoided an event. The analysis also combined several medicines, so it cannot show that every drug provides the same benefit.

Diagnosis codes may be incomplete, and prescription records do not prove how consistently people used the drugs or at what dose. Differences in access, cost, weight change and other unmeasured factors may also have influenced the findings.

The study adds to the argument for testing prevention strategies earlier in the diabetes-risk pathway. Confirming the size of any benefit, and identifying who benefits most, will require stronger comparisons along with a realistic look at cost and access.

If you are interested in this topic, please read articles about Best and worst diets for obesity, according to science, and Weight loss, regardless of method, beneficial for metabolic health in obesity and type 2 diabetes.

Source: Mayo Clinic.