GLP-1 reduced heart failure risk by 46%: 8 study takeaways

The GLP-1 tirzepatide, the active ingredient in Eli Lilly's Mounjaro, was found to reduce the risk of heart failure by 46% among individuals with obesity, according to a study published Nov. 16 in The New England Journal of Medicine and presented at the American Heart Association's annual Scientific Sessions.

"While tirzepatide causes considerable weight loss, research is lacking on its effects on cardiovascular outcomes," lead study author Milton Packer, MD, distinguished scholar in cardiovascular science at Dallas-based Baylor University Medical Center in Dallas and visiting professor at Imperial College in London, said in a Nov. 16 news release from AHA.

As part of the international Summit trial, researchers studied the effects tirzepatide had on participants' health and the rate of worsening heart failure events or death due to cardiovascular disease.

Here are eight takeaways from the study: 

1. The study included 731 heart failure patients with an ejection fraction of at least 50% and a body-mass index of at least 30. Of the participants 364 received tirzepatide and 367 received a placebo for at least 52 weeks, with a media follow-up of 104 weeks.
   
   
2. Worsening heart failure events occurred in 8% of the tirzepatide group and 14.2% of the placebo group, representing a 46% reduction in risk among tirzepatide users.
   
   
3. Worsening heart failure events or cardiovascular death occurred in 9.9% of the tirzepatide group and 15.3% of the placebo group, representing a 38% combined risk reduction for tirzepatide users.
   
   
4. One year of trizepatide use was associated with 11.9% greater weight loss.
   
   
5. Participants taking tirzepatide for one year were able to walk an average of 18.3 meters farther than the placebo group during a six-minute walking test.
   
   
6. Researchers utilized the Kansas City Cardiomyopathy Questionnaire clinical summary score, a commonly used survey that analyzes a heart failure patient’s symptoms, quality of life, physical and social function, at 52 weeks of the study. Participants taking tirzepatide had an approximate score of 19.5 while participants in the placebo group had an approximate score of 12.7.
   
   
7. Of all the participants, 6.3% and 1.4% discontinued use of tirzepatide or the placebo, respectively, due to adverse effects.
   
   
8. One of the study's limitations was the use of body mass index for participation criteria. Individuals with heart failure may have a higher than normal waist-to-height ratio while falling under the BMI measurement for obesity.