Abstract T P156: Awareness Of Atrial Fibrillation And Appropriate Antithrombotic Treatment Will Attenuate Stroke Severity And Improve Clinical Outcome In Acute Ischemic Stroke Patients With Atrial Fibrillation

Abstract

Background: Ischemic stroke due to atrial fibrillation (AF) is markedly increasing in Korea. Appropriate use of oral anticoagulants for the patients with AF is very important. We elucidated the relationship between international normalized ratio (INR) values on stroke severity and clinical outcomes in patients with acute ischemic stroke and AF. Methods: Study subjects were extracted from prospectively-designed stroke registries of three academic hospitals from 2003 to 2013. We selected 2,303 patients with AF who visited our hospital within 7 days after onset. Persistent or paroxysmal AF is confirmed by electrocardiography or Holter monitoring. We adopted INR values extracted in emergency room, and the initial stroke severity and functional outcome were assessed by baseline and discharge National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale. Results: One thousand three hundred two patients (50.1%) were aware of their AF before admission. The awareness was markedly lower than that of hypertension (88.7%) and diabetes (88.1%). After exclusion of the patients who did not know their medication history, 48.5% were not on antithrombotic treatment, 17.1% on warfarin, 25.8% on mono antiplatelet treatment, 4.1% on dual or triple antiplatelet therapy, and 4.5% on warfarin and antiplatelet. Besides, the patients who were taking warfarin with a therapeutic INR (2.0~3.0) were only 68 (3.0%). Admission and discharge NIHSS score was significantly lower in the group of patients taking warfarin (median 6, interquartile range [2,13]). Admission and discharge NIHSS scores were lowest in the group of patients with optimal INR level (admission NIHSS; INR<1.5, 8[3,14]; INR=1.5-2.0, 5.5[2,13]; INR=2.0-3.0, 4[2,10], INR ≥3.0, 5.5[2,15.75], p=0.026 and discharge NIHSS; INR<1.5, 4[1,11]; INR=1.5-2.0, 3[1,10.25]; INR=2.0-3.0, 2[0,7.75]; INR ≥3.0, 2.5[1,11.25], p=0.024) Conclusion: Awareness of AF has been poor and underuse or inappropriate use of warfarin was widespread. Suboptimal (INR=1.5-2.0) or optimal (INR=2.0-3.0) use of warfarin can be associated with lower initial stroke severity and clinical outcome. Therefore, the education about appropriate anticoagulation is needed for the general public and health professionals.