Boosting anticoagulation adherence in atrial fibrillation and atrial flutter: the impact of a simple nudge strategy before elective electrical cardioversion

Abstract Background Atrial fibrillation (AF) and atrial flutter (AFL) are important causes of morbidity and increase stroke risk, particularly after conversion to sinus rhythm. Therapeutic anticoagulation for ≥3 weeks reduces this risk to <1%, but poor adherence to anticoagulation remains an obstacle, leading to increased morbidity and economic burden. Therefore, exploration of helpful adherence strategies is crucial. Purpose This study aimed to evaluate the effectiveness of a nudge strategy, using educational letters delivered via mail, in improving anticoagulation adherence before elective electrical cardioversion (EEC). Methods In this prospective interventional study, outpatients with AF or AFL scheduled for EEC between May 2023 and July 2024 at a Portuguese hospital were randomly assigned to receive either an educational letter about anticoagulation (intervention group) or standard care (oral information - control group). On the day of the EEC, optimal adherence, defined as no missed anticoagulant doses in the previous 3 weeks, was assessed by two health professionals and a questionnaire was applied. Patients with suboptimal adherence received additional education and their EEC was postponed. Results The study included 152 patients (mean age 65±11, 37.5% female, mean CHA2DS2-VASc score 2.5±1.6): 79 in the intervention group and 73 in the control group. There were no significant differences in sociodemographic or clinical characteristics between the groups (table 1). Optimal adherence was significantly higher in the intervention group (95%) compared to the control group (82%, p=0.013). Fewer patients in the intervention group were discharged without undergoing EEC (5% versus 18%; Odds Ratio 0.25 [95% Confidence Interval 0.08-0.79]; p=0.013), highlighting the potential benefits of this nudge strategy (figure 1). Conclusion Low awareness about the importance of anticoagulation is a key factor in suboptimal adherence. A simple nudge strategy, such as sending an educational letter, can significantly improve compliance in patients with AF or AFL. This approach is inexpensive, accessible, and may reduce the risks associated with poor anticoagulation adherence and the costs of postponing procedures like EEC.Table 1- Features of the participants Figure 1- Study flowchart