IJCS | Volume 33, Nº1, January / February 2019

DOI: 10.5935/2359-4802.20190083 68 ORIGINAL ARTICLE International Journal of Cardiovascular Sciences. 2020;33(1):68-78 Mailing Address: Maria de Fátima de Araújo Geraldes Universidade Federal da Bahia - Rua Augusto Viana, s/n. Postal Code: 40110-060, Salvador, Salvador, BA - Brazil. E-mail: mfageraldes@gmail.com Trends and Predictors of Oral Anticoagulation in Patients with Atrial Fibrillation: A Serial Cross-Sectional Study from 2011 to 2016 Maria de Fátima de Araújo Geraldes, 1, 2 Eduardo Sahade Darze, 1, 2 P aulo Novis Roch a¹ Universidade Federal da Bahia,¹ Salvador, BA – Brazil Hospital Cárdio Pulmonar,² Salvador, BA - Brazil Manuscript received on March 03, 2019, revised manuscript on April 15, 2019, accepted on May 22, 2019. Abstract Background: Despite the efficacy of vitamin K antagonists against stroke in patients with atrial fibrillation (AF), the underuse of this therapy is well documented. Objectives: To evaluate trends and predictors of oral anticoagulants utilization in patients with AF. Methods: Observational, retrospective, serial cross-sectional study between 2011-2016. Comparisons between groups were performed using the Student t, Mann-Whitney and Chi-square tests. Logistic regression was used to identify independent predictors of anticoagulation. A p value < 0.05 was considered significant. Results: A total of 377 patients were analyzed. The mean age was 70 ± 15 years; 52% were male and 75% were anticoagulated (20% with VKA and 55% with DOAC). Over 5 years, the overall frequency of anticoagulation increased by 22.4%. The use of DOACs increased from 29% to 70%, whereas the use of VKA decreased from 36% to 17%. The use of antiplatelet agents alone also fell from 21% to 6%. The predictors of anticoagulation were previous episodes of AF (OR 3.1, p < 0.001), hypertension (OR 3.0, p < 0.001) and HASBLED score (OR 0.5, p < 0.001). The predictors of DOAC use were serum creatinine (OR 0.2, p = 0.002), left atrial size (OR 0.9, p = 0.003) and biological valve prosthesis (OR 0.1, p = 0.007). Of the 208 patients using DOACs, 63 (30%) received inadequate prescriptions: 5 with severe drug interactions and 58 with incorrect dosing. Conclusions: Between 2011 and 2016, DOACs were rapidly incorporated into clinical practice, replacing AVKs and antiplatelets, and contributing to greater use of anticoagulation in patients with AF. (Int J Cardiovasc Sci. 2020;33(1):68-78) Keywords: Atrial Fibrillation; Anticoagulants; Brain Ischemia; Vitamin K/antagonists & inhibitors; Thromboembolism/ prevention & control. Introduction Atrial fibrillation (AF) affects about 1–2%of theworld’s population and is associated with a five-fold increased risk of stroke. The use of vitamin K antagonists (VKA) as anticoagulants reduces the risk of stroke or systemic embolismby 64%and all-cause death by 26%. 1-7 However, observational studies have shown that only 50–60% of patients with AF eligible for the use of anticoagulants are anticoagulated. Reasons for underutilization of VKAs include numerous drug and food interactions and the inconvenience of laboratory monitoring process, which make it difficult tomaintain the International Normalized Ratio (INR) in the narrow therapeutic range, placing patients at risk for ischemic and hemorrhagic events. 8-10 Over the past 10 years, several randomized trials, involving more than 70,000 patients withAF, compared the use of AVK with direct-acting oral anticoagulants (DOACs). In these studies, DOACs were at least as effective as VKAs in preventing thromboembolic events and promoted a significant reduction in the frequency of intracranial hemorrhage. 11 In addition, DOACs