Association of Baseline Comorbidities With First-Year Adherence to GLP-1 Receptor Agonists in Patients With Diabetes or Obesity: A Retrospective Cohort Study

Abstract

Background: Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are increasingly used for diabetes and obesity. Yet, the role of comorbidities on adherence, and variability due to drug subtype or indication remains understudied.

Objective: Study objective was to (a) evaluate association between baseline comorbidities and digestive system adverse events on first-year GLP-1 RA adherence and (b) assess how associations differ across GLP-1 RA subtypes and between patients with diabetes and obesity.

Method: We conducted a retrospective cohort study of adults with type 1 or type 2 or obesity initiating GLP-1 RAs between 2018 and 2023 using the University of California Health Data Warehouse. Primary outcome was first-year adherence association with baseline comorbidity and digestive system adverse event status. Adherence odds ratios based on exposure were estimated using regression. Analyses were stratified by indication and drug type.

Result: Among 69 049 adults who initiated a GLP-1 RAs between 2018 and 2023, 59.3% had diabetes and 74.4% had obesity. Among patients with diabetes, hypertensive disorder (OR: 1.06, 95% CI: 1.01-1.10), hyperlipidemia (OR: 1.17, 95% CI: 1.12-1.22), and chronic kidney disease (CKD) (OR: 1.14, 95% CI: 1.08-1.21) increased adherence likelihood. Among patients with obesity, hyperlipidemia (OR: 1.10, 95% CI: 1.05-1.15) and CKD (OR: 1.09, 95% CI: 1.02-1.16) were associated with increased adherence. In patients with diabetes, atherosclerotic cardiovascular disease (ASCVD) and digestive system adverse events reduced adherence likelihood (OR: 0.90, 95% CI: 0.86-0.95) and (OR: 0.94, 95% CI: 0.90-0.98), respectively. Results were similar for patients with obesity. Findings remained consistent overall in brand-specific analyses.

Conclusion and relevance: Comorbidities affected GLP-1 RA adherence with variation by drug and indication. Further research is needed to understand drivers of these patterns and how they may inform future strategies to support adherence.

Keywords: GLP-1 RA; adherence; comorbidity; diabetes; glucagon-like peptide-1 receptor agonist; obesity; type 2 diabetes.