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Published on: February 26, 2013
Assessment of Non-Vitamin K Antagonist Oral Anticoagulant Dosing Patterns in Turkish Patients with Non-Valvular
Özer Badak1, Demet Özkaramanlı Gür2, Çağlar Kaya3
1Department of Cardiology, Dokuz Eylül University, Faculty of Medicine, İzmir, Türkiye.
Objective:
We aimed to assess the real-world label adherence of non-vitamin K antagonist oral anticoagulant (NOAC) dosing patterns, including apixaban, edoxaban, and rivaroxaban, in Turkish patients with atrial fibrillation.
Methods:
This was an observational, prospective, cross-sectional, multicenter study. Patients with atrial fibrillation (AF) who were prescribed NOACs within the last 4 months were recruited from 34 cardiology clinics in Türkiye. Baseline data were initially collected, and patient awareness was evaluated at 3-4 weeks.
Results:
A total of 903 patients were enrolled in the study. The mean age was 72.84 ± 10.17 years. We found that 140 (15.5%), 721 (79.8%), and 42 patients (4.7%) were prescribed off-label low, on-label, and off-label high dosing, respectively. The age of the patients in the on-label group was significantly lower than that of those in the off-label low and off-label high groups (both P < 0.001). Female patients were more frequently observed in the off-label high group (P = 0.019). The body mass index values of the patients in the off-label high-dose group were significantly lower than those in the other groups (P < 0.001). The perception of income levels also revealed significant differences between the groups (P = 0.010). Furthermore, the HAS-BLED scores (the Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile International Normalized Ratio, Elderly, Drugs/Alcohol Concomitantly) were significantly lower in the on-label group than in the other groups (P < 0.001). Similarly, the CHA2DS2-VASc [the Congestive Heart Failure, Hypertension, Age ≥75 (Doubled), Diabetes, Stroke (Doubled), Vascular Disease, Age 65-74, and Sex Category (Female)] scores were significantly lower in the on-label group than in the off-label group (P < 0.001).
Conclusion:
The clinical impact off-label NOAC prescriptions may vary. Therefore, raising clinician awareness about proper NOAC dosing could aid in improve the outcomes.
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