Adherence to Rivaroxaban, Dabigatran, and Apixaban for Stroke Prevention in Incident, Treatment-Naïve Nonvalvular Atrial Fibrillation

Abstract

BACKGROUND Non-vitamin K antagonist oral anticoagulants (NOACs) are widely used for prevention of stroke secondary to nonvalvular atrial fibrillation (NVAF). Increased use of NOACs is partially a result of simplified regimens compared with warfarin, which has been associated with poor adherence and persistence to therapy. Few studies have assessed adherence to NOACs, especially using contemporary data now that multiple NOACs are available. OBJECTIVE To evaluate adherence to NOACs in a cohort of newly diagnosed NVAF patients who are commercially insured. METHODS Incident, treatment-naïve NVAF patients were identified in 2013 from a large claims database. Patients were included who initiated rivaroxaban, dabigatran, or apixaban within 30 days after diagnosis. Subjects were required to have 12 months of pre-index information to assess demographic and clinical characteristics (comorbidities, CHA2DS2-VASc, and HAS-BLED scores). Adherence to the index medication and adherence to any oral anticoagulant was assessed using proportion of days covered (PDC) at 3, 6, and 9 months. The number of switches and gaps in therapy were also evaluated. Analyses were stratified by stroke risk scores, and a logistic regression model was used to control for factors that may predict high adherence (PDC ≥ 0.80). RESULTS A total of 3,455 rivaroxaban, 1,264 dabigatran, and 504 apixaban users were included with no major clinical or demographic differences between groups. At 3, 6, and 9 months of follow-up, dabigatran had lower adherence (PDC = 0.77, 0.67, and 0.62) compared with rivaroxaban (PDC = 0.84, 0.75, and 0.70; P < 0.001) and apixaban (PDC = 0.82, 0.75, and 0.71; P < 0.001), as well as nearly twice the number of switches to either other anticoagulants or antiplatelet therapy. At 9 months, 55.0% of rivaroxaban initiators had PDC ≥ 0.80, which was comparable with 56.8% for apixaban and significantly greater than 46.7% for dabigatran (P < 0.001). Adherence was higher overall as stroke risk increased and showed dabigatran had consistently lower adherence compared with the other NOACs. Overall adherence to any oral anticoagulants, allowing for switches to another NOAC or warfarin, was not dependent on the index medication (9-month PDC = 0.74, 0.71, and 0.74 for rivaroxaban, dabigatran, and apixaban initiators). Adjusted analyses showed that increasing age and comorbid hypertension and diabetes were associated with higher adherence. Compared with rivaroxaban, dabigatran initiators had nearly 30% lower odds of being adherent to their index medication, and no differences were observed between apixaban and rivaroxaban. At 9 months, there were no differences between NOACs for overall adherence to oral anticoagulants. CONCLUSIONS In this real-world analysis of adherence to NOACs, rivaroxaban and apixaban had favorable profiles compared with dabigatran, and rivaroxaban appeared to have higher overall adherence among the NOACs. Clinicians and managed care organizations should consider the implications of lower adherence on clinical outc...

Safety and Efficacy of Novel Oral Anticoagulants Versus Warfarin in Medicare Beneficiaries With Atrial Fibrillation and Valvular Heart Disease

“…The proportion of days covered did not differ significantly for patients with and without valvular disease. This is consistent with previous reports of NOAC adherence on the basis of administrative data 25. Overall, 25%, 20%, and 17% of dabigatran, rivaroxaban, and warfarin users ceased the initial anticoagulant within 90 days.…”

Adherence to Rivaroxaban, Dabigatran, and Apixaban for Stroke Prevention for Newly Diagnosed and Treatment-Naive Atrial Fibrillation Patients: An Update Using 2013-2014 Data

“…14 Our study is an update of a previous study by our group, which used data from 2013 to assess adherence to NOACs. 19 Overall, results of the previous study are similar to the current study, although a slightly larger advantage for rivaroxaban versus apixaban was observed using the updated data.…”

“…Mainly, patients with gaps in therapy of 3 days or who switched to another therapy were censored. Thus, based on the results from this study and previous studies, 14,19 the censoring criteria would have a stronger effect on the dabigatran group, that is, more dabigatran users would be censored, potentially leaving a biased dabigatran user group to compare with rivaroxaban users.…”

“…The purpose of this study was to update the evidence from a previous study on adherence to NOACs in a cohort of commercially insured, newly diagnosed NVAF patients in the United States, 19 by comparing adherence and treatment patterns using 2013–2014 data.…”

Real‐World Adherence and Persistence with Direct Oral Anticoagulants in Adults with Atrial Fibrillation

“…First, in well‐designed clinical trials with carefully selected and motivated patients, premature discontinuation of DOAC therapy was reported in 21–25.3% of patients . Second, while multiple studies have evaluated adherence patterns with single DOAC agents, few have compared adherence patterns between multiple DOACs or have evaluated these patterns over a longer time frame . Third, with warfarin therapy there are established patient education and management models that are associated with better clinical outcomes compared to routine care, but these models do not yet exist for DOAC therapy.…”