In real-world data from over 34,000 matched patients with diabetes and heart disease, tirzepatide reduced cardiovascular events by 20% and mortality by 40% versus dulaglutide, while showing similar outcomes to semaglutide.
40% lower mortality vs. dulaglutideTirzepatide initiators had a 40% lower rate of all-cause death (HR 0.60) compared to dulaglutide initiators among 9,233 matched pairs with type 2 diabetes and existing cardiovascular disease.
What the researchers found
After propensity score matching: Tirzepatide vs. dulaglutide (9,233 pairs) — tirzepatide had lower modified MACE (IR 31.3 vs 39.4 per 1,000 person-years; HR 0.80, 95% CI 0.65-0.99), driven by 40% lower all-cause mortality (HR 0.60, 95% CI 0.43-0.83). Post hoc analysis showed lower pneumonia hospitalization with tirzepatide vs dulaglutide. Tirzepatide vs. semaglutide (25,266 pairs) — modified MACE rates were similar (IR 23.7 vs 23.2; HR 1.03, 95% CI 0.90-1.17).
Why it matters
This is the largest real-world head-to-head comparison of tirzepatide against both dulaglutide and semaglutide for cardiovascular outcomes. It provides immediate clinical guidance: tirzepatide is clearly superior to dulaglutide for heart protection and equivalent to semaglutide. For patients currently on dulaglutide, switching to tirzepatide may reduce cardiovascular risk. For those choosing between tirzepatide and semaglutide, cardiovascular protection appears similar.
How the study worked
Two target trial emulations using commercially insured US adults (June 2022-December 2024) with type 2 diabetes and established atherosclerotic cardiovascular disease. New initiators of tirzepatide were propensity score matched 1:1 with dulaglutide initiators (9,233 pairs) and separately with semaglutide initiators (25,266 pairs). Primary outcome was modified MACE (composite of non-fatal MI, non-fatal stroke, and all-cause death). Incidence rates and hazard ratios were estimated.
What this study cannot tell us
Observational target trial emulation — despite propensity score matching, unmeasured confounding cannot be excluded. The study used insurance claims data, which may have coding inaccuracies. The relatively short follow-up period (up to ~2.5 years) may not capture long-term differences. Tirzepatide initiators may differ from dulaglutide/semaglutide initiators in unmeasurable ways (e.g., provider enthusiasm, patient motivation). The pneumonia finding was post hoc and hypothesis-generating. Commercially insured patients may not represent Medicare or uninsured populations.
How to read the evidence
This is a large, well-designed observational study using target trial emulation methodology — considered the most rigorous approach for real-world evidence when randomized trials aren't available. The large sample sizes and propensity score matching add strength, but observational design means causation cannot be definitively established.
When this study was published
Published in 2026 in Diabetes Care, this is among the most current and largest real-world comparisons of tirzepatide vs. GLP-1 agonists for cardiovascular outcomes.
The bigger picture
This study helps resolve a key clinical question as GLP-1 and dual-agonist prescribing surges. The finding that tirzepatide matches semaglutide's cardiovascular protection while offering superior metabolic benefits (weight loss, HbA1c reduction) strengthens the case for tirzepatide as a first-choice agent for patients with diabetes and heart disease. The mortality advantage over dulaglutide may accelerate switching from older GLP-1 agonists.
Questions still open
- What drives the 40% mortality advantage of tirzepatide over dulaglutide — is it the GIP component, greater weight loss, or other factors?
- Will the cardiovascular equivalence of tirzepatide and semaglutide hold up in longer follow-up periods?
- Should patients currently on dulaglutide be switched to tirzepatide for cardiovascular benefit?
Common questions
Is tirzepatide better than other diabetes drugs for the heart?
Should I switch from dulaglutide to tirzepatide?
Read the original research
Comparative Effectiveness of Tirzepatide Versus Dulaglutide or Semaglutide on Major Cardiovascular Events in Type 2 Diabetes and Cardiovascular Disease: Insights From Two Target-Trial Emulations.
Diabetes care
Citation
Ostrominski, John W; Ortega-Montiel, Janinne; Wexler, Deborah J; Everett, Brendan M; Cromer, Sara J; Byrne, Caroline F; Glynn, Robert J; Paik, Julie M; Patorno, Elisabetta. (2026). Comparative Effectiveness of Tirzepatide Versus Dulaglutide or Semaglutide on Major Cardiovascular Events in Type 2 Diabetes and Cardiovascular Disease: Insights From Two Target-Trial Emulations.. Diabetes care. https://doi.org/10.2337/dc25-3063