Medication Adherence to Semaglutide versus Empagliflozin in Adults with Type 2 Diabetes: A Retrospective Observational Study in Saudi Arabia.

PURPOSE: Sodium-glucose cotransporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1RA) are widely prescribed, yet medication adherence varies. This study evaluated real-world adherence and persistence to semaglutide and empagliflozin among adults with T2D and assessed the associations between adherence and clinical outcomes. PATIENTS AND METHODS: A retrospective observational study was performed using electronic health records and pharmacy dispensing data from a military hospital in Tabuk, Saudi Arabia, between July 1, 2023 and June 30, 2024. Adults with T2D (≥18 years old) prescribed semaglutide or empagliflozin were included. Medication adherence was quantified using proportion of days covered (PDC). Persistence was defined by absence of treatment gap ≥60 days. Associations between adherence and patient characteristics, and clinical out-comes, were examined. RESULTS: Among 5087 patients (mean age 57.9 ± 12.3 years, mean T2D duration 10.3 ± 7.6 years), 4020 received empagliflozin and 1067 initiated semaglutide. Adherence (PDC ≥ 80%) was observed in 57.7% of semaglutide and 60% of empagliflozin users. Persistence was lower 40% (semaglutide) and 45% (empagliflozin) met the criteria. Sociodemographic variables were not significant predictors of medication adherence. CONCLUSION: Medication adherence and persistence to both semaglutide once-weekly injection and oral empagliflozin were suboptimal among T2D patients. Adherent patients to both medications experienced a significant improvement in glycemic control. Targeted strategies are needed to enhance patient motivation for consistent medication use and timely refills.