UCSF

Background

Nonadherence to direct oral anticoagulants to prevent stroke occurs in up to 40% of atrial fibrillation patients. Underlying reasons are poorly understood.

Objectives

This study quantified patient-reported reasons for nonadherence and identified strategies to improve adherence.

Methods

This is a cross-sectional survey of atrial fibrillation patients in 2 academic health systems who reported apixaban nonadherence. We examined patient-reported reasons for nonadherence and level of nonadherence (assessed by a validated 3-item adherence measure) using a multivariable logistic regression model.

Results

Of 419 study patients, 41.5% were women. The mean age was 71.1 ± 10 years and mean CHA₂DS₂VASc score was 3.2 ± 1.6. About two-thirds had adherence scores ≥80 (mild nonadherence) and one-third scores <80 (poor adherence). In all groups, forgetfulness contributed to nonadherence. Attitudes/beliefs associated with adherence score <80 included: not believing apixaban was needed (odds ratio [OR]: 12.24 [95% CI: 2.25-66.47]); medication cost (OR: 3.97 [95% CI: 1.67-9.42]); and fear of severe bleeding (OR: 3.28 [95% CI: 1.20-8.96]). Strategies that patients with adherence scores <80 selected as helping "a great deal/a lot" to increase adherence included bloodwork to evaluate efficacy (56%), physician counseling about adherence (55%), and having a reversal agent (39%). Almost one-half of all patients did not disclose nonadherence to their providers.

Conclusions

Patients may not disclose their nonadherence to prescribers, and attitudes related to apixaban nonadherence differ among patients with mild nonadherence versus poor adherence. While all patients may benefit from strategies to address forgetfulness, concerns related to the purpose of apixaban, cost, and bleeding risk may require special attention in those with poor adherence.