Long-Term Adherence to Direct Oral Anticoagulants in Patients with Atrial Fibrillation: A Comparative Cross-Sectional Study

Background: Long-term treatment with direct oral anticoagulants (DOAC) is required for the majority of patients with nonvalvular atrial fibrillation (AF) to prevent ischemic stroke and systemic embolism. Adherence to therapy may impact clinical outcomes. Therefore, the purpose of this study was to assess the potential impact of structured follow-up on long-term adherence to DOAC therapy compared to standard care.

Methods: This is a cross sectional study on the implementation phase of medication adherence to DOACs, comparing patients with AF following completion of structured follow-up of minimally 1 year with those who received standard care. All patients used DOACs for more than 2 years and completed a questionnaire on adherence. Adherence was measured with the Morisky Medication Adherence Scale-8 (MMAS-8) score and assessed via an online web portal.

Results: A total of 212 patients were included. The mean MMAS-8 score was 7.55 (SD 0.93) after structured follow-up and 7.25 (SD 1.01) for standard care; p = 0.045. Following structured follow-up 64.1% of patients had a high adherence (MMAS score of 8) compared to 50% receiving standard care; p = 0.05. Patients following structured follow-up on a once daily DOAC regime had higher MMAS-8 scores compared to those on a twice daily regime; 7.74 (SD 0.74) versus 7.00 (SD 1.22); p < 0.001. The rates of minor bleedings were 10.6% versus 21.4% respectively, p = 0.038.

Conclusion: In patients on long-term DOAC treatment, adherence to therapy was significantly increased after receiving an initial period of structured follow-up compared to standard care. Additionally, adherence to DOAC therapy was higher with once-daily treatment regimen. Significant more minor bleedings were reported in the standard care group. These results indicate that implementation of structured follow-up of patients with AF using DOACs merits further evaluation.