BARRIERS AND ENABLERS TO ORAL ANTICOAGULANT ADHERENCE IN PATIENTS MANAGED AT AN INSTITUTIONAL ATRIAL FIBRILLATION CLINIC: A QUALITATIVE, THEORY-INFORMED STUDY

Abstract

Oral anticoagulant (OAC) adherence is associated with stroke reduction in patients with atrial fibrillation (AF). Despite copious research aimed at improving adherence, less than half of AF patients are adherent to OAC. One explanation for persistently low OAC adherence rates is the lack of understanding around barriers and enablers to OAC adherence. OAC adherence optimization requires a systematic, theory-driven approach to behaviour change. The Behaviour Change Wheel (BCW) is a validated framework that can be used to design, tailor, implement, and evaluate behavior change interventions (BCI). The BCW incorporates the capability, opportunity, motivation (COM-B) model of behaviour change which can be linked to the Theoretical Domains Framework (TDF) to determine barriers and enablers to why behaviour, such as OAC adherence, occurs. These can be mapped to proven BCI aimed at improving adherence. The aim of this study was to identify barriers and enablers to OAC adherence in AF patients. This qualitative descriptive study included 10 purposefully sampled adult participants taking an OAC, who received care at a Canadian AF clinic and possessed at least one risk factor for non-adherence. A TDF-based, semi-structured interview was conducted and data was analyzed using a 14-domain TDF coding guide. Themes related to barriers and enablers to OAC adherence were generated using the COM-B model. Eight participants were at least 65 years old; five participants were female; eight participants had paroxysmal AF, two had persistent AF; two participants each had AF diagnosis for less than one month and between one month and six months, whereas six participants had AF for greater than six months; three participants had a CHADS2 of one and seven participants had a CHADS2 of at least two; one participant was receiving warfarin and nine participants were receiving a DOAC. The top three enablers coded were knowledge (47 utterances), beliefs about consequences (26 utterances), and social influences (25 utterances) and the top three barriers coded were knowledge (27 utterances), environmental context and resources (17 utterances), and memory, attention and decision processes (four utterances). Five enabler themes and three barrier themes were identified (Table 1). Modifiable barriers and enablers to OAC adherence were identified in AF patients receiving care at an AF clinic. Enablers encompassed capability, opportunity, and motivation drivers while barriers included only capability and opportunity impediments. Implementation of future BCI to improve OAC adherence should address these themes.