Direct oral anticoagulants: patient reported adherence and minor bleedings

Abstract

Data regarding adherence and minor bleeding on direct oral anticoagulants in everyday life are still sparse. Inclusion criteria: treatment initiated with dabigatran, rivaroxaban or apixaban in non-valvular atrial fibrillation patients from a center in northern Sweden between 2011 and 2019 (n = 668). Exclusion criteria: cognitive impairment, dose dispensing, need of interpreter or hospital admission (n = 67). By a telephone interview adherence was measured in 569 patients (response rate 94.8%) using the 8-item Morisky medication adherence scale and minor bleeding was asked for. CHA₂DS₂-VASc and HAS-BLED scores were collected from medical records. The number (n), mean age, mean treatment duration, mean (points) CHA₂DS₂-VASc and HAS-BLED scores was with dabigatran (n = 175, 73.3 years, 17.8 months, 3.6 p and 2.2 p), rivaroxaban (n = 198, 73.7 years, 21months, 3.8 p and 2.1 p) and apixaban (n = 196, 72.7 years, 15.2 months, 3.4 p and 2.1 p). Adherence was high for dabigatran, rivaroxaban and apixaban in 54%, 76% and 53%; intermediate in 37%, 20% and 37% or low in 9%, 4% and 10% respectively. High adherence (Morisky score 8) distinguished rivaroxaban (p < 0.0001) and in patients with CHA₂DS₂-VASc ≥ 4 p, (p < 0.0001). Patients on rivaroxaban/apixaban reported more minor bleedings (37% / 28%) compared to dabigatran (13%), (p < 0.001). Only 61% of the patients followed prescription. Adherence to rivaroxaban was significantly better, maybe due to the once daily dosing regimen, and furthermore among patients with higher risk for stroke. Minor bleedings were less common in the dabigatran group. The impact of minor bleedings on adherence and a possible relationship to clinical outcomes need to be further studied.

Keywords: 8-item Morisky medication adherence scale; Adherence; Atrial fibrillation; Direct oral anticoagulants; Minor bleedings; Real world.

Fig. 1

Flow chart of the study population. A total of 668 patients with non-valvular atrial fibrillation treated with dabigatran, apixaban or rivaroxaban were identified in Auricula, Sundsvall, the Swedish national quality registry for AF and anticoagulation. After exclusion of patients with dose dispensing, cognitive impairment, need of interpretation or current admission to a hospital; 601 patients remained. A telephone interview was conducted with 569 patients; additional 32 patients did not attend the call

Fig. 2

Adherence in DOAC treated NVAF-patients according to 8-item Morisky medication adherence scale. Dabigatran (n = 175), rivaroxaban (n = 198) and Apixaban (n = 196). Rivaroxaban had the highest share of patients (76%) with Morisky high adherence (score 8) compared to Morisky intermediate + low adherence (score < 8) to both dabigatran (54%) and apixaban (53%) (p < 0.0001)

Fig. 3

Relationship between CHA₂DS₂-VASc score and Morisky medication adherence assessed in NVAF patients with dabigatran (n = 175), rivaroxaban (n = 198) and apixaban (n = 196). High adherence (Morisky score 8) in patients with very high risk for stroke (CHA₂DS₂ VASc score ≥ 4 p) was significantly in favor of rivaroxaban compared to dabigatran (p < 0.0001) and apixaban (p < 0.00001) respectively

Fig. 4

Relationship between occurrence of minor bleeding complication and Morisky medication adherence in non-valvular atrial fibrillation patients treated with dabigatran (no bleeding complication n = 153, minor bleeding complication n = 22, exclusion major bleeding n = 0), rivaroxaban (no bleeding complication n = 124, minor bleeding complication n = 73, exclusion major bleeding n = 1) or apixaban (no bleeding complication n = 139, minor bleeding complication n = 55, exclusion major bleeding n = 2). The occurrence of minor bleeding complication was not associated with lower degree of adherence in patients treating with dabigatran, rivaroxaban or apixaban