The Efficacy of Glucagon-Like Peptide-1 Receptor Agonists as Adjunct Therapy to Insulin in Patients With Type 1 Diabetes: A Systematic Review and Meta-Analysis

Abstract

Objective Glucagon-like peptide-1 (GLP-1) receptor agonists (RAs) are a class of antidiabetic that is well-established in type 2 diabetes. Although their efficacy in type 1 diabetes remains uncertain, this meta-analysis aimed to evaluate the benefits of adding GLP-1 RAs to insulin in patients with type 1 diabetes. The goal was to summarize advantages and drawbacks from updated existing literature. This study aimed to evaluate the effects of adding GLP-1 RAs to insulin therapy for type 1 diabetes, focusing on blood glucose control, body weight, insulin needs, and cardiovascular safety. This study also analyzed updated existing literature to assess the benefits and risks of this dual treatment approach. Methods We searched PubMed, MEDLINE, Scopus, and Cochrane Library for relevant studies using keywords related to GLP-1 agonists, insulin, and type 1 diabetes. For the eligibility criteria, this study necessitated randomized controlled trials that compared GLP-1 RAs plus insulin versus insulin plus placebo in patients with type 1 diabetes, regardless of age or sex. The primary outcomes focused on hemoglobin A1c, with secondary outcomes evaluating changes in body weight, insulin requirements, systolic blood pressure, and pulse. All statistical analyses were conducted using the RevMan Web software developed by Cochrane, and a P value of <.05 was considered statistically significant. Results The analysis of 12 studies (1570 patients) showed that GLP-1 RAs added to insulin reduced the hemoglobin A1c level significantly to −0.3% (−0.43 to −0.17), suggesting efficacy in type 1 diabetes. However, moderate to significant heterogeneity and bias were observed. GLP-1 RAs also led to a −4.6 (−4.64 to −4.57)-kg higher weight reduction and lower insulin needs at −4.32 (−4.38 to −4.24) IU, with a consistent reduction in the systolic blood pressure but an increase in the heart rate. Conclusion This meta-analysis of 12 studies with 1567 participants shows significant benefits of GLP-1 RA therapy in type 1 diabetes management but highlights the need to tailor treatments and explore further because of identified heterogeneity.