Abstract TP172: Newly Diagnosed Atrial Fibrillation in Ischemic Stroke is an Independent Predictor of Mortality in Underserved Populations

Abstract

Stroke is a major cause of death and disability in the United States and underserved communities are at higher risk for complications, severity and recurrence of stroke compared to the general population. Atrial fibrillation (A-fib) predisposes to ischemic stroke occurrence; however, newly diagnosed A-fib at the time of stroke, and its predictive value in the outcome of underserved patients has not been reported. Aim: To explore the clinical significance of newly diagnosed A-fib among underserved populations with ischemic stroke. Methods: Retrospective cohort of patients with acute ischemic stroke diagnosis at John H. Stroger Hospital in 2014. New A-fib confirmed by electrocardiography. Stroke events were confirmed by magnetic resonance imaging or computed tomography. Given our small event rate we dichotomized National Institute of Health Stroke Scale (NIHSS) into severe (≥15) and non-severe (<15) to make groups comparable. Demographic and potential confounding variables were independently extracted. SPSS version 24 was used and Kaplan Meier and Cox logistic regression with forward modeling were applied. Results: A total of 424 patients for the analysis, mean±SD age of 59.2±11.9 years, mostly male (57.5%), the majority African Americans (59.7%) followed by Hispanics (20.3%). The mean±SD follow up was 22.7±16.6 months, and 24 patients died (5.7%). A-fib was newly diagnosed in 8 (1.9%) patients and a third (37.5%) met indication or accepted anticoagulation. We adjusted for age, hypertension, diabetes, prior stroke, prior A-fib, anticoagulation, alcohol, smoking history and NIHSS. In our model NIHSS ≥15 was the strongest predictor or mortality (HR: 8.04; 95%CI: 2.14-30.25; p<0.01) followed by newly diagnosed A-fib (HR: 5.47; 95%CI: 1.29-23.12; p=0.02). Patients with newly diagnosed A-fib had worse overall survival when compared to those without A-fib (mean 517 days vs 1237 days, p<0.01). Conclusion: Our results are hypothesis generating, and suggest that ischemic stroke secondary to newly diagnosed A-fib carries worse overall survival. It’s plausible that this subset of patients may require a tailored longitudinal plan to reduce risk of poor outcomes in an undeserved population.