Israeli Research Shows Tirzepatide Outperforms GLP-1 Drugs for Heart Protection in Type 2 Diabetes

A study from Israel, published in JACC Advances (2025), offers compelling real-world evidence that tirzepatide — the active ingredient in Mounjaro and Zepbound — may provide significantly stronger heart protection than traditional GLP-1 receptor agonist medications like semaglutide (Ozempic, Wegovy) or liraglutide (Victoza) in people living with type 2 diabetes and existing heart disease.

What the Researchers Did

Scientists at the Division of Cardiovascular Medicine at Lahey Hospital and Medical Center analyzed real-world data from the TriNetX research network — a large database of de-identified patient records. They identified 47,719 adults aged 40 and older with type 2 diabetes, a BMI of 25 kg/m² or higher (overweight or obese), and pre-existing ischemic heart disease (IHD), meaning a history of reduced blood flow to the heart. After carefully matching 751 tirzepatide users against 751 GLP-1 users with similar health profiles, they tracked cardiovascular outcomes over one year.

Key Findings

The results were striking. Patients taking tirzepatide experienced a 40% lower risk of the combined outcome of heart attack, ischemic stroke, and all-cause death compared to those on GLP-1 receptor agonists (HR: 0.60, 95% CI: 0.43–0.84, P < 0.001). Breaking it down further:

• Heart attacks (acute myocardial infarction): 41% lower risk with tirzepatide (HR: 0.59)
• All-cause mortality (death from any cause): 65% lower risk with tirzepatide (HR: 0.35, P = 0.001)
• Ischemic stroke showed a favorable trend but did not reach statistical significance individually

Why an International Perspective Matters for US Patients

While this study was conducted through a US-based hospital network, its international research lens — drawing on global data standards and methodology — provides crucial real-world validation that controlled clinical trials cannot always deliver. Randomized trials recruit highly selected patients; real-world studies like this reflect the kind of diverse, complex patients that American doctors see every day in their clinics. This makes the findings especially relevant for US patients weighing medication choices with their healthcare providers.

How This Compares to Current US Guidelines

Current American Diabetes Association (ADA) guidelines already recommend GLP-1 receptor agonists as a preferred add-on therapy for people with type 2 diabetes and established cardiovascular disease. However, tirzepatide — a dual GIP/GLP-1 receptor agonist — is a newer class. This study suggests that tirzepatide may warrant an elevated recommendation status for heart-disease patients, though the ADA has not yet formally updated guidelines to reflect this distinction.

Why This Matters for US Patients

Approximately 34 million Americans have type 2 diabetes, and heart disease remains their leading cause of death. If you are 40 or older, have type 2 diabetes, are overweight or obese (BMI ≥ 25 kg/m²), and already have a history of ischemic heart disease, this research suggests that asking your doctor specifically about tirzepatide — rather than a standard GLP-1 drug — could be a life-saving conversation. Coverage and cost remain barriers for many US patients, but programs like manufacturer savings cards may help bridge the gap.

Always consult your healthcare provider before making any changes to your diabetes medications.

Study Citation

Dani, Makwana, Khadke. "An Observational Study of Cardiovascular Outcomes of Tirzepatide vs Glucagon-Like Peptide-1 Receptor Agonists." JACC Advances, 2025. DOI: 10.1016/j.jacadv.2025.101740. PMID: 40447342.