Abstract 5622: Effectiveness of Hybrid Therapy With Warfarin and Statins to Reduce the Incidence of Ischemic Stroke in High-risk Patients With Atrial Fibrillation

Abstract

Background HMG-CoA reductase inhibitor statins have been recently used to prevent ischemic stroke in patients with coronary artery disease. However, whether or not such statins truly reduce the risk of ischemic stroke in patients with atrial fibrillation (AF) remains to be clearly elucidated. Methods We performed a retrospective cohort study at 4 Japanese centers. The study sample consisted of a cohort of 1152 patients (mean age, 67±10 years; men, 64 %; 513 paroxysmal AF) who had documented AF on electrocardiograms before August 2002 and who also visited our hospitals after September 2002. The statin group consisted of 179 patients (16%). A cox proportional hazards analysis was performed to control for baseline differences. We assessed the incidence of ischemic stroke. Results During a follow-up of 61±23 months, 151 patients experienced ischemic stroke. Since the statin group had more risk factors for stroke, such as a history of congestive heart failure, hypertension and diabetes mellitus, than the non-statin group, the statin group had a higher CHADS2 score (congestive heart failure, hypertension, age, diabetes, stroke [doubled]) than the non-statin group (statin group 1.93±1.15 vs. non-statin group 1.42±1.19, p<0.001). The incidence of ischemic stroke was similar in both groups (statin group 12.0% vs. non-statin group, 17.5%, P = 0.08). For patients with a CHADS2 score ranging from 2– 6 with concomitant warfarin use, however, ischemic stroke was significantly less frequent in the statin group (statin group 11.7% vs. non-statin group, 26.0%, P = 0.045) although the incidence of major bleeding was similar in both groups (statin group 14.4% vs. non-statin group, 21.1%, P = 0.508). After adjustment for differences in baseline clinical variables, statin use was significantly associated with the incidence of ischemic stroke (hazard ratio[HR], 0.43; 95% confidence interval[CI], 0.23 to 0.83; P = 0.012), Conclusions In comparison to warfarin alone, the hybrid therapy with warfarin and statin was therefore suggested to be more effective in high-risk patients with atrial fibrillation.