The relationship between anticoagulation knowledge, health literacy and medication adherence in patients with atrial fibrillation

Introduction: Atrial fibrillation (AF) is associated with significant morbidity, mortality and economic implications. Patients with AF are often prescribed anticoagulants for the prevention of cardioembolic stroke and other embolic events. Patients’ anticoagulation knowledge, level of medication adherence and health literacy are known to affect treatment outcomes. However, contemporary data regarding the relationships between these variables are lacking.

Aims: The aim of this study was to determine the relationships between anticoagulation knowledge, health literacy and medication adherence, and to investigate if knowledge is affected by health literacy levels.

Methods: A cross-sectional survey was conducted in 48 patients with AF identified from general practices. The Anticoagulation Knowledge Tool (AKT) was used to assess anticoagulation knowledge, the Short Test of Functional Health Literacy in Adults (s-TOHFLA) for health literacy and the 8-item Morisky Medication Adherence Scale (MMAS) for medication adherence. The relationships between study variables were assessed using Pearson’s correlation coefficient, t-tests and regression analysis.

Result: Participants in the study had mean scores of 61.6±15.8 for the AKT, 7.2±1.1 for the MMAS-8, and 24.7±9.5 for the sTOHFLA. A significant correlation was observed between both anticoagulation knowledge and health literacy with medication adherence (0.45, p<0.01 and 0.36, p < 0.05, respectively). Participants with adequate health literacy had a significantly higher knowledge score than those with limited health literacy (66.1% vs 55.8%, p <0.05), and regression analysis showed that both anticoagulation knowledge and health literacy scores were significant independent predictors of adherence levels (0.03(95%CI,0.01–0.05), p=0.001 and 0.04(95%CI, 0.01–0.07), p= 0.01, respectively).

Discussion: Anticoagulation knowledge, health literacy and medication adherence were closely related and suboptimal in patients with AF. Further research in a larger population is required to definitely elucidate the magnitude of this problem. Future studies should also focus on developing effective interventions to improve anticoagulation knowledge, health literacy and medication adherence in this patient population.