Knowledge and adherence to oral anticoagulant therapy among patients with non-valvular atrial fibrillation at Hanoi Heart Hospital in 2025

Abstract

Objective: Non-valvular atrial fibrillation (NVAF) is a major risk factor for embolic stroke, necessitating lifelong oral anticoagulation (OAC) therapy. The effectiveness of OAC in clinical practice is heavily dependent on patient adherence and knowledge. This study aimed to describe the current status of knowledge and practice regarding OAC therapy and to identify factors associated with treatment adherence among NVAF outpatients at the Voluntary Outpatient Department of Hanoi Heart Hospital).

Methods: A descriptive cross-sectional study was conducted on 100 NVAF outpatients from May 2025 to December 2025. Data were collected through face-to-face interviews using a structured questionnaire. Knowledge was assessed using the Oral Anticoagulation Knowledge Tool (AKT) by Obamiro, where a score of ≥60% was considered "adequate". Treatment adherence was measured using the 8-item Morisky Medication Adherence Scale (MMAS-8), classified into high (8 points), medium (6-7 points), and low (<6 points) adherence levels. Statistical analysis was performed using SPSS 20.0, utilizing Fisher’s Exact Test and univariate logistic regression to calculate Odds Ratios (OR) with a 95% confidence interval (CI).

Results: The mean age of the participants was 63.4 ± 10.1 years, with 57% being male. Most patients had co-morbidities, including hypertension (51%), heart failure (46%), and coronary artery disease (41%). Regarding knowledge, 78% of participants were classified as having "inadequate knowledge". Specifically, 84% could not correctly identify the name of their anticoagulant, 98% believed they could stop the medication when feeling well, and 72% were unaware that missing a dose could worsen their condition. In terms of adherence, only 25% achieved high adherence, while 53% showed medium adherence and 22% showed low adherence. Common barriers included forgetting medication while traveling (49%) and general difficulty in remembering the daily regimen (39%). Associated factors for adequate knowledge included having a reminder for medication (OR=5.64, 95%CI: 1.71-18.56, p<0.01). Factors significantly associated with better adherence included clear counseling from healthcare providers (OR=4.33, 95%CI: 1.60-11.69, p<0.01), having a medication reminder (OR=3.07, 95%CI: 1.05-8.95, p=0.04), and possessing adequate treatment knowledge (OR=3.50, 95%CI: 1.27-9.62, p=0.02).

Conclusion: Knowledge and adherence regarding oral anticoagulation therapy among NVAF patients at Hanoi Heart Hospital are considerably limited. The study highlights that clinical outcomes can be significantly improved through effective medical counseling, family support systems (reminders), and targeted health education. These findings underscore the necessity for personalized patient management strategies and continuous educational interventions to optimize stroke prevention in AF populations.