Diabetes Obes Metab

GLP-1 agonists lower weight and HbA1c in adults with T1DM

October 22, 2025

GLP-1 RAs and tirzepatide are effective adjuncts for weight loss and metabolic risk reduction in adults with T1DM and obesity, without increased risk of hypoglycemia or diabetic ketoacidosis (DKA). Weight loss was less than in non-diabetic populations, underscoring the need for further randomized trials to validate these findings and optimize adjunctive therapy in this group.

Study details: A real-world, 12-month observational study included 250 adults with T1DM and BMI ≥27 kg/m², comparing weight loss (primary outcome) with tirzepatide (n = 35), semaglutide (n = 36), liraglutide (n = 97), and usual care (n = 82). Secondary endpoints were changes in metabolic risk markers, including lipids, renal and liver function, BP, and HbA1c.

Results: All three agents produced significant weight loss: tirzepatide led to the greatest reduction (10.9%), followed by semaglutide (9.9%) and liraglutide (7.1%) (all p<0.001). Dose-dependent effects were noted for tirzepatide and semaglutide. Modest HbA1c reductions were observed (tirzepatide: 0.65%, semaglutide: 0.33%, liraglutide: 0.23%). Semaglutide and liraglutide reduced LDL-cholesterol, and liraglutide lowered urine albumin-to-creatinine ratio. No severe hypoglycemia or DKA occurred.

Source:

Al Ozairi E, et al. (2025, October 6). Diabetes Obes Metab. Weight loss in people with type 1 diabetes over 12 months: Real-world data comparing tirzepatide, semaglutide and liraglutide. https://pubmed.ncbi.nlm.nih.gov/41048008/