Introduction Anti-diabetes medication regimen adherence is a clinical challenge in elderly patients with type 2 diabetes (T2D) and other comorbidities associated with aging. Glucagon-like peptide-1 receptor agonists (GLP-1RA) therapies such as exenatide once weekly (QW), exenatide twice daily (BID), and liraglutide once daily (QD) are an increasingly used class of drugs with proven efficacy and tolerability. Real-world evidence on adherence to GLP-1RAs in elderly or disabled patients is limited. To further the understanding of this drug class, the current study examined medication adherence in Medicare patients aged ≥65 years with T2D initiating a GLP-1RA. Methods This retrospective cohort study used medical and pharmacy claims between 2010 and 2013 for Medicare members in a United States health plan diagnosed with T2D who were new initiators of either exenatide QW (n = 537), exenatide BID (n = 923), or liraglutide QD (n = 3,673). Included patients were between the ages of 65 and 89 and were continuously enrolled for 6 months pre- and post-index. Medication adherence was examined during the post-index period using proportion of days covered (PDC) ≥80% and ≥90%. Results A significantly higher percentage of patients receiving exenatide QW had a PDC ≥80% (43.2%) versus exenatide BID (39.0%, P