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Early changes in body composition with tirzepatide in adults with obesity: a real-world BIA study
Nikolaos Angelopoulos1, Andreas Rizoulis1, Anastasios Boniakos1
1Hellenic Endocrine Network, Endocrine Department, Athens, Greece.
Background:
Tirzepatide induces substantial weight loss, but real-world data on early body composition changes remain limited.
Methods:
We evaluated short-term changes in body composition in 51 adults with obesity treated with tirzepatide for 12 weeks, using bioelectrical impedance analysis.
Results:
Body weight decreased by 8.75 kg (-8.18%, P < 0.001), primarily driven by fat mass reduction (-6.87 kg, P < 0.001), with a smaller decrease in soft lean mass (-1.73 kg, P < 0.001). Despite this, the relative proportion of lean mass increased (+3.00 percentage points, P < 0.001), indicating preferential fat loss. Approximately 78% of total weight loss was attributable to fat mass.
Conclusion:
These findings suggest that short-term tirzepatide therapy leads to favorable body composition changes, characterized by predominant fat loss and relative preservation of lean mass, supporting its metabolic benefit in real-world clinical practice.
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