title: The awareness, efficacy, safety, and time in therapeutic range of warfarin in the Turkish population: WARFARIN-TR.
abstract: OBJECTIVE
  The awareness, time in therapeutic range (TTR), and safety of warfarin therapy were investigated in the adult Turkish population.
  
  
  METHODS
  This multicenter prospective study includes 4987 patients using warfarin and involved regular international normalized ratio (INR) monitoring between January 1, 2014 and December 31, 2014. TTR was calculated according to F.R. Roosendaal's algorithm. Awareness was evaluated based on the patients' knowledge of warfarin's affect and food-drug interactions.
  
  
  RESULTS
  The mean TTR of patients was 49.52±22.93%. The patients with hypertension (55.3%), coronary artery disease (23.2%), congestive heart failure (24.5%), or smoking habit (20.8%) had significantly lower TTR levels than the others. Of the total number of patients, 42.6% had a mechanical valve, 38.4% had non-valvular atrial fibrillation (AF), and 19% had other indications for warfarin. Patients with other indications had lower TTR levels than those with mechanical valve and non-valvular AF (p=0.018). Warfarin awareness decreased in higher age groups. The knowledge of warfarin's food-drug interactions was 55%. People with higher warfarin awareness had higher TTR levels. Patients with ≤8 INR monitoring/year had lower TTR levels (46.4±25.3 vs. 51.1±21.3, respectively, p<0.001) and lower awareness (44.6% vs. 60.6%, p<0.001) than patients with ≥8 INR monitoring/year. In this study, 20.1% of the patients had a bleeding event (major bleeding 15.8%, minor bleeding 84.2%) within a year.
  
  
  CONCLUSIONS
  Both the mean TTR ratios and awareness of the Turkish population on warfarin therapy were found to be low. It was thought that low TTR levels of the Turkish population may be caused by the low awareness of warfarin, warfarin's food-drug interactions, and high rates of concomitant diseases.
authors.affiliation: Department of Cardiology, Faculty of Medicine, Mersin University, Mersin-Turkey. ahmetcelik39@hotmail.com.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Çelik
authors.affiliation: Department of Cardiology, Koşuyolu Education and Research Hospital, İstanbul-Turkey.
authors.forename: Servet
authors.initials: S
authors.lastname: İzci
authors.affiliation: Department of Cardiology, Faculty of Medicine, Fırat University, Elazığ-Turkey.
authors.forename: Mehmet Ali
authors.initials: MA
authors.lastname: Kobat
authors.affiliation: Department of Cardiology, Samsun Education and Research Hospital, Samsun-Turkey.
authors.forename: Ahmet Hakan
authors.initials: AH
authors.lastname: Ateş
authors.affiliation: Department of Cardiology, Faculty of Medicine, Amasya University, Amasya-Turkey.
authors.forename: Abdülkadir
authors.initials: A
authors.lastname: Çakmak
authors.affiliation: Department of Cardiology, Siyami Ersek Education and Research Hospital, İstanbul-Turkey.
authors.forename: Yasin
authors.initials: Y
authors.lastname: Çakıllı
authors.affiliation: Department of Cardiology, Faculty of Medicine, Cumhuriyet University, Sivas-Turkey.
authors.forename: Mehmet Birhan
authors.initials: MB
authors.lastname: Yılmaz
authors.affiliation: Department of Cardiology, Faculty of Medicine, Ege University, İzmir-Turkey.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Zoghi