© 2018 International Journal of the Cardiovascular Academy | Published by Wolters Kluwer - Medknow 86 Abstract Original Article IntroductIon Warfarin is an effective oral anticoagulant which is used for the prevention of thromboembolic events especially in patients with atrial fbrillation (AF) and prosthetic valve. Warfarin reduces the stroke by 64% compared to the placebo in patients with AF, and it is the unique treatment for prosthetic valve patients. [1,2] The effcacy and safety of warfarin are dependent on maintenance of the international normalized ratio (INR). The target INR values alter according to the reason of warfarin use; the TTR should be above 70% for optimal effcacy and safety of warfarin use. [3-6] The risk of total mortality and major bleeding increases with TTR value below 70%. [3,5] However, many studies from Turkey have shown that the number of patients with TTR value above 70% is very low in daily practice. Previous studies have shown that many factors may cause a low rate of TTR in different study populations. In the present study, we aimed to evaluate the factors that might be caused by adequate anticoagulation control in patients treated with warfarin in the WARFARIN-TR (The Awareness, Background: In the present study, we aimed to evaluate the factors that might be caused by adequate anticoagulation control in patients treated with warfarin for any reason. Methods: The WARFARIN-TR (The Awareness, Effcacy, Safety, and Time in Therapeutic Range of Warfarin in Turkish Population) study included 4987 patients using warfarin between January 1, 2014 and December 31, 2014. Time in therapeutic range (TTR) was calculated according to F. R. Roosendaal’s algorithm with linear interpolation. The study population divided into two groups; adequate international normalized ratio (INR) control when TTR ≥70% (Group 1, n = 1068, 21.4%) and inadequate INR control when TTR <70% (Group 2, n = 3919, 78.6%). All demographic and clinic characteristics of the patients were compared to determine possible factors that might be cause adequate warfarin use. Results: The mean age of the study population was 60.7 ± 13.5 years, and there was no signifcant difference between groups. The mean TTR value of Group 1 was signifcantly higher than Group 2 (80 ± 8.5 vs. 40.9 ± 17.2; P < 0.001). The traditional cardiovascular risk factors were similar between groups except hypertension (Group 1 51.4% and Group 2 56.4%; P = 0.004) and chronic kidney disease (Group 1 8.3% and Group 2 5.5%; P = 0.001). There were no signifcant differences between groups regarding bleeding. The awareness of warfarin use was signifcantly higher in Group 1 patients than Group 2 patients. Multivariate logistic regression analysis revealed that age (odds ratio [OR], 1.007; P = 0.014), hypertension (OR, 0.821; P = 0.01), atrial fbrillation (OR, 1.180; P = 0.033), chronic kidney disease (OR, 1.697; P < 0.001), to know warfarin use reason (OR, 1.699; P < 0.001), and know to food-drug interaction with warfarin (OR, 1.583; P < 0.001) were independent predictors of adequate coagulation. Conclusion: Our study demonstrated that a low proportion of patients taking warfarin achieve an adequate TTR in daily practice. Furthermore, the patients with adequate TTR are more aware of warfarin use. Keywords: Adequate anticoagulation, warfarin, warfarin awareness Address for correspondence: Dr. Salih Kilic, Department of Cardiology, Doctor Ersin Arslan Research and Training Hospital, Sahinbey, Gaziantep, Turkey. E‑mail: kilicsalihhh@gmail.com Access this article online Quick Response Code: Website: http://www.ijcva.com DOI: 10.4103/IJCA.IJCA_43_18 This is an open access journal, and artcles are distributed under the terms of the Creatve Commons Atributon-NonCommercial-ShareAlike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as appropriate credit is given and the new creatons are licensed under the identcal terms. For reprints contact: reprints@medknow.com How to cite this article: Kilic S, Çelik A, Seyis AS, Kurmus O, Tülüce K, Emren ZY, et al. Potential factors affecting the anticoagulation control in patients treated with warfarin: Results WARFARIN-TR study. Int J Cardiovasc Acad 2018;4:86-9. Potential Factors Affecting the Anticoagulation Control in Patients Treated with Warfarin: Results WARFARIN‑TR Study Salih Kilic, Ahmet Çelik 1 , Ali Sabri Seyis 2 , Ozge Kurmus 3 , Kamil Tülüce 4 , Zeynep Yapan Emren 5 , Ali Kemal Kalkan 6 , Mehdi Zoghi 7 Department of Cardiology, Doctor Ersin Arslan Research and Training Hospital, Gaziantep, 1 Department of Cardiology, Faculty of Medicine, Mersin University, Mersin, 2 Department of Cardiology, Istinye University Liv Hospital, Istanbul, 3 Department of Cardiology, Ufuk University, Faculty of Medicine, Ankara, 4 Department of Cardiology, Karsiyaka State Hospital, 6 Department of Cardiology, Tepecik Research and Training Hospital, 7 Department of Cardiology, Faculty of Medicine, Ege University, Izmir, 5 Department of Cardiology, Sandikli State Hospital, Afyon, Turkey