Evaluating the effect of Semaglutide as add-on therapy on glycemic control and continuous glucose monitoring outcomes in adults with type 1 diabetes: A two-year real-world data study

Abstract

Aims: To evaluate the long-term efficacy of a GLP-1 receptor agonist (GLP-1RA, Semaglutide) as an adjunct to insulin therapy in adults with type 1 diabetes (T1D), using continuous glucose monitoring (CGM) metrics alongside weight and metabolic outcomes.

Methods: In this retrospective chart review of adults with T1D on intensive insulin therapy, GLP-1RA was initiated and maintained for two years. Glycemic and metabolic parameters were evaluated at baseline, 12 months (T12), and 24 months (T24) during combination therapy.

Results: A total of 67 adults with T1D (56.7 % males, 43.3 % females; mean age 31.8 years, SD: 6.11; mean diabetes duration 16.6 years, SD: 5.16) were included. By 24 months, we observed improved %TIR_70-180 from 46 % to 71 % and %TIR_70-140 from 28.1 % to 47.9 % (p < 0.001 for both). GRI, including CHypo and CHyper, showed sustained reductions, and glycemic variability improved, with CV% falling from 46.3 % to 33.6 % (p < 0.001). HbA1c improved from 8.2 % to 7.1 %, with total daily insulin dose decreasing from 1.4 to 0.7 IU/kg/day (p < 0.001). Body weight and lipid profile improved, with significant reductions in weight (p < 0.001), LDL (p < 0.001), and triglycerides (p < 0.05). No hospitalizations for DKA or major adverse cardiovascular events (MACE) occurred, and short discontinuation had no significant impact on metabolic or glycemic outcomes.

Conclusions: The adjunctive use of GLP-1RA in T1D shows potential for improving glycemic stability and metabolic parameters without increasing hypoglycemia risk. However, further studies are needed to confirm these effects across diverse populations and over more extended periods to fully establish their long-term efficacy and safety.

Keywords: Continuous glucose monitoring; GLP-1 receptor agonists; Glycemic variability; Insulin therapy; Type 1 diabetes.