The Trends in Utilizing Nonvitamin K Antagonist Oral Anticoagulants in Patients With Nonvalvular Atrial Fibrillation

Abstract

Dabigatran and rivaroxaban are novel nonvitamin K antagonist oral anticoagulants (NOACs) approved for thromboprophylaxis in atrial fibrillation (AF). In Turkey, like other countries, the efficacy of translation of the clinical trial results and current guideline recommendations into daily clinical practice is yet to be discovered. Using data from medical records of three tertiary care cardiology centers, we identified patients with nonvalvular AF on dabigatran or rivaroxaban treatment. Baseline characteristics and utilization trends were compared between dabigatran and rivaroxaban groups. Secondarily, clinical events including ischemic stroke and/or transient ischemic attack, systemic embolism, and bleeding were evaluated. Among 294 patients with AF included, dabigatran was utilized in 177 (60.2%) and rivaroxaban in 117 (39.8%). Overall, 76% of patients had received long-term warfarin therapy. The use of 110 mg twice a day (55.4%) was the prevailing strategy in dabigatran group, whereas in rivaroxaban group 20 mg every day (67.5%) was the preferred option. Of the patients, 37.3% had severe valvular disease in which mitral regurgitation was the predominant valve abnormality. Scores of CHADS, CHADSVASc, and HAS-BLED were similar in both the groups. Of the patients, 24% in dabigatran group and 13.7% in rivaroxaban group were prescribed the lower dose inappropriately. The two NOACs did not differ significantly in terms of clinical events. The results of this study indicate that in daily practice, the physicians' behavior in utilizing the NOACs is shaped by the clinical trials and the guideline recommendations. On the other hand, in dose selection, this adherence is not of high quality.

Impact of direct oral anticoagulant off‐label doses on clinical outcomes of atrial fibrillation patients: A systematic review

“…These findings corroborate that receiving ILD doses, especially unintended, might be a risk factor for recurrent ischaemic stroke (Figure D ). Similarly, Kilickiran Avci et al also reported an inappropriate reduced dose in 1/3 of the studied patients with NVAF, with a high risk of stroke, what was considered a worrying pattern of practice.…”

Impact on Drug Safety of Variation in Adherence: The Need for Routinely Reporting Measures of Dose Intensity in Medication Safety Studies Using Electronic Health Data

“…Similarly, the lower level of use of the 150-mg strength in the European study may be reflective of the use of lower doses in countries where the 110-mg strength is available. In Turkey, only 45 % of dabigatran use was for the higher strength [ 29 ], and a European survey reported 61 % of dabigatran use in adults was at the 150-mg strength [ 30 ].…”

Preemptive Dose Adjustment Effect on the Quality of Anticoagulation Management in Warfarin Patients With Drug Interactions: A Retrospective Cohort Study

“…11 This has led warfarin to remain as the most widely prescribed oral anticoagulant in many countries despite challenges with its management. [12][13][14][15][16][17] Variety of models are used in warfarin management including patient selfmanagement, specialized anticoagulation clinics, and pharmacist-managed anticoagulation clinics. 18 Pharmacistmanaged anticoagulation clinic represents a model that provides patients with more consistent management, closer monitoring, more education, and awareness especially in regard to interacting drugs and food which can ultimately alter warfarin efficacy and safety.…”