EFFICACY OF TIRZEPATIDE ON WEIGHT LOSS, MUSCLE MASS AND CARDIOVASCULAR HEALTH IN THE ADULT POPULATION WITH DIABETES TYPE 2, OVERWEIGHT OR OBESITY: A SYSTEMATIC REVIEW

Zuzanna Strojek; Monika Szyszkowska; Michał Petkow; Mateusz Żyła; Liwia Prorok; Katarzyna Lipska; Aleksandra Potempa; Aleksandra Ustaszewska; Aleksandra Oszczypała; Zofia Parol

doi:10.31435/ijitss.2(50).2026.5992

Authors

Zuzanna Strojek Faculty of Medicine, Medical University of Warsaw, Warsaw, Poland https://orcid.org/0009-0005-8857-5670
Monika Szyszkowska Faculty of Medicine, Medical University of Warsaw, Warsaw, Poland https://orcid.org/0009-0006-5367-0026
Michał Petkow Faculty of Medicine, Medical University of Warsaw, Warsaw, Poland https://orcid.org/0009-0008-3398-9069
Mateusz Żyła Faculty of Medicine, Medical University of Warsaw, Warsaw, Poland https://orcid.org/0009-0003-9005-620X
Liwia Prorok Faculty of Medicine, Medical University of Warsaw, Warsaw, Poland https://orcid.org/0009-0008-3762-514X
Katarzyna Lipska Faculty of Medicine, Medical University of Warsaw, Warsaw, Poland https://orcid.org/0009-0003-5670-7726
Aleksandra Potempa Faculty of Medicine, Medical University of Warsaw, Warsaw, Poland https://orcid.org/0009-0004-2698-4957
Aleksandra Ustaszewska Faculty of Medicine, Medical University of Warsaw, Warsaw, Poland https://orcid.org/0009-0001-5651-5906
Aleksandra Oszczypała Faculty of Medicine, Medical University of Warsaw, Warsaw, Poland https://orcid.org/0009-0006-5809-3934
Zofia Parol Faculty of Medicine, Medical University of Warsaw, Warsaw, Poland https://orcid.org/0009-0007-0885-2637

DOI:

https://doi.org/10.31435/ijitss.2(50).2026.5992

Keywords:

Tirzepatide, Mounjaro, GIPR Agonist, Obesity, Diabetes Type 2, Weight Loss

Abstract

Objective: Tirzepatide is a dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist designed to assist patients with weight reduction. Aim of this article is to systematically evaluate the efficacy of tirzepatide on body weight, muscle mass, and systemic cardiometabolic parameters in adults with T2DM, overweight, or obesity.

Methods: A PubMed database search for randomised clinical trials with full text in English available published within 5 years was performed. Studies covering tirzepatide’s efficacy on BMI, body composition, and cardiometabolic markers in the population of adults with T2DM or overweight, obesity were included.

Results: Tirzepatide demonstrated dose-dependent weight reduction, with the 15-mg dose achieving mean losses of 20.9% to 25.3% in adults with obesity and 12.8% to 15.7% in those with T2DM [2]. BMI reductions reached up to -10.4 kg/m² [30] [33]. Body composition analyses revealed a healthy preservation of lean mass, with approximately 75% of weight loss being fat mass and 25% being lean mass [4] [21].Thigh muscle fat infiltration reduction by -0.36 to -0.48 percentage point was observed, indicating improved muscle quality [27]. Cardiometabolic benefits included HbA1c reductions (up to 2.6%) [7] [8], net blood pressure lowering (6.8 mmHg systolic; 4.2 mmHg diastolic) [18], and substantial triglyceride reductions (up to 37.6%) [16] [18]. Drug withdrawal led to weight regain and a partial-to-complete reversal of cardiometabolic improvements [15].

Conclusion: Tirzepatide assists in weight reduction and improves cardiovascular and glycemic risk factors. These effects are consistent across baseline BMI categories, though chronic maintenance is required to sustain metabolic gains.

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