INTRODUCTION: obesity is a chronic and relapsing disease. Tirzepatide, a dual GLP-1 and GIP receptor agonist, has demonstrated weight loss exceeding 20 % at higher doses. However, real-world data remain limited, particularly regarding body composition and muscle function.
METHODS: fifty-two patients with obesity (71.2 % women; mean age 47 ± 12.4 years) treated with tirzepatide and followed for at least 4 months were analyzed. Body composition was assessed by bioimpedance analysis and muscle function was assessed using a digital dynamometer (JamarrPlus® Digital Hand Dynamometer, Patterson Medical, USA at baseline and at the end of the study.
RESULTS: the mean tirzepatide dose was 5.1 ± 1.4 mg/week. Weight loss (9.94 ± 4.8 kg) and percentage weight loss (9.7 ± 4.8 %) were similar to those reported in SURMOUNT-1.Significant reductions were observed in body weight (104.6 ± 19.6 vs. 94.6 ± 20.8 kg; p < 0.0001), BMI (36.7 ± 5.3 vs. 34.9 ± 6.8 kg/m²; p = 0.02), and waist circumference (112.2 ± 11.5 vs. 105.4 ± 16.1 cm; p = 0.008).A significant decrease was also found in absolute fat mass (44.4 ± 11.1 vs. 37.1 ± 10.2 kg; p < 0.0001),body fat percentage (43.2 ± 6.2 vs. 39.0 ± 6.5 %; p < 0.0001), and visceral fat index (17.4 ± 5.1 vs. 14.4 ± 4.9; p < 0.0001).Lean mass was preserved (42.8 ± 16.8 vs. 41.8 ± 15.8 kg; p = 0.052), as was muscle function(31.6 ± 11.9 vs. 31.4 ± 11.6 kg; p = 0.5) after 4 months of treatment.
CONCLUSIONS: in real-world clinical practice, tirzepatide demonstrated significant reductions in body weight and fat mass, even at low doses, while preserving lean mass and muscle function. These findings reinforce its potential as an effective and safe therapeutic option for the management of obesity.