Study finds diabetes drug tirzepatide reduces heart attack and stroke risk in high-risk patients

A study published in The BMJ reveals that adding the diabetes drug tirzepatide (Mounjaro) to standard care for patients with type 2 diabetes and heart disease reduces the risk of major adverse cardiovascular events (MACE) by 32% over one year compared to sitagliptin. Tirzepatide was associated with a 33% lower risk of heart attacks and fewer hospitalizations from infections. Meanwhile, a separate 10-year Danish study in The Lancet Regional Health highlights that poor adherence to diabetes medications increases cardiovascular risk by 27%, rising to 73% for younger adults.

Tirzepatide cardiovascular benefits

• ▪In the BMJ study, patients taking tirzepatide experienced a 32% relative reduction in major adverse cardiovascular events at one year, with a 2.9% event rate compared to 4.4% for those taking sitagliptin.
• ▪The BMJ study found that tirzepatide was associated with lower rates of infections requiring hospital admission, infection-related death, and death from any cause compared to sitagliptin.
• ▪A study published in The BMJ in August 2026 found that adding the GLP-1 receptor agonist tirzepatide to standard care for patients with type 2 diabetes and heart disease is associated with a lower risk of major cardiovascular events.
• ▪The BMJ study associated tirzepatide with a 33% lower risk of heart attack compared to sitagliptin, though no meaningful difference was found in ischemic stroke cases.

Real-world clinical practice evidence

• ▪Researchers Nils Krüger and colleagues stated that trial-anchored evidence from clinical practice can estimate the expected cardiovascular benefits of tirzepatide to inform shared decision-making.
• ▪A linked editorial in The BMJ noted that while the tirzepatide study provides a transparent estimate for routine care, it does not establish a mortality indication or define the best sequence for cardiometabolic therapy.

Diabetes medication adherence impact

• ▪The Danish registry study found that younger adults with low adherence to diabetes medication had a 73% higher rate of cardiovascular events before age 55 compared to consistent users.
• ▪A separate study published in The Lancet Regional Health – Europe tracked nearly 80,000 Danish adults over 10 years and found that low adherence to diabetes medication was linked to a 27% higher rate of major cardiovascular events.

Study methodology using claims data

• ▪The BMJ study analyzed clinical practice data from two U.S. health insurance claims databases between May 2022 and May 2025, encompassing 52,971 individuals with type 2 diabetes, a body mass index of at least 25, and established heart disease.
• ▪To balance differences between the treatment groups, researchers of the BMJ study utilized a statistical technique called propensity score overlap weighting.

Sitagliptin comparison group

• ▪In the BMJ study cohort, 35,353 patients started tirzepatide and 17,618 started sitagliptin, with outcomes monitored from the first day of treatment up to one year.
• ▪Researchers of the BMJ study chose sitagliptin as a neutral placebo proxy because several prior studies have shown it has no effect on cardiovascular outcomes.