Comparative real-world outcomes of tirzepatide vs semaglutide in patients with obesity and type2 diabetes: A retrospective propensity-matched cohort study

Background: With the increasing use of GLP-1 receptor agonists and dual GIP/GLP-1 agonists for managing obesity and type 2 diabetes, understanding their real-world effectiveness and safety is essential. This TriNetX analysis directly compares clinical outcomes among patients treated with tirzepatide vs semaglutide. Method: We utilized data from the TriNetX Research Network, identifying patients aged > 40 years or with obesity (“BMI ≥ 30 kg/m2”) and type 2 diabetes (HbA1c ≥ 6.5% or fasting glucose.≥ 125 mg/dL). Qualifying events were restricted to May 1, 2022, through November 21, 2024. We established two cohorts: one initiating tirzepatide and another semaglutide, ensuring each patient had at least three prescriptions and no prior exposure to the comparator drug or other GLP-1 receptor agonists. The index date was defined as the first co-occurrence of the obesity/diabetes criteria and the respective drug prescription. To ensure comparability, we performed 1:1 propensity matching, resulting in 47,804 patients in each cohort. Outcomes, including all-cause mortality, MACE, heart failure exacerbation, ischemic stroke/TIA, hospitalization/ED use, dementia, UTI, adverse Gastrointestinal (GI) effects, and changes in HbA1c, were assessed within a 1-year window after the index date. Results: Our matched cohort had a mean age of 75 years, with 45% male patients and 74% identified as white. Patients treated with tirzepatide experienced a significantly lower incidence of MACE at “(“3.7% vs 4.1% (RR 0.918, 95% CI 0.862-0.978). All-cause mortality was also lower with tirzepatide (0.2% vs. 0.4%; Risk Ratio 0.436, 95% CI 0.338-0.562). The tirzapetide group achieved better glycemic control with a lower mean HbA1c (6.565% vs. 6.848%; p < 0.001) during the follow-up. There was no significant difference in heart failure exacerbation or UTI incidence. GI side effects were slightly less frequent in the tirzepatide cohort (9.8% vs. 10.2%; Risk Ratio 0.959, 95% CI 0.924-0.997), while hospitalization or emergency visits were comparable between the two groups. Conclusion: In this propensity matched cohort of patients with obesity and type 2 diabetes, tirzepatide demonstrated improved cardiometabolic outcomes compared to semaglutide, including lower all-cause mortality and lower HbA1c. These findings support the cardiovascular safety and efficacy of tirzapetide and highlight the need for further studies to evaluate its effectiveness in broader clinical populations.