633 The Role of CHA2DS2-VASc Score vs. Anticoagulation for Predicting Morbidity and Mortality for Ischemic Bowel Disease Secondary to Atrial Fibrillation

Abstract

INTRODUCTION: Atrial fibrillation is a common disorder with potentially multiple adverse outcomes, one such being ischemic bowel disease. The aims of this study are: to evaluate the role of CHA2DS2-VASc score as a predictor of higher mortality in patients who have atrial fibrillation and ischemic bowel disease, i.e., if a higher CHA2DS2-VASc score is associated with higher mortality; to evaluate whether being on anticoagulation is associated with a lower mortality for such patients in this population. METHODS: This retrospective study reviewed patients admitted to three community hospitals over a 3 year period with the primary diagnoses of atrial fibrillation and ischemic bowel disease. The subject cohort was gathered with ICD 10 codes. Baseline characteristics such as age, sex, CHA2DS2-VASc Score, mean Cr, and subjects use of anticoagulation were analyzed. Hazard ratios, P-values, Confidence Intervals, and a Cox proportional hazards model for the baseline characteristics were calculated. Kaplan-Meier curves were calculated and then plotted together for subjects on anticoagulation versus those not on anticoagulation. The area under the receiver operating characteristic (ROC) curve was employed to assess the predictive power of CHA2DS2-VASc score for mortality development among ischemic bowel disease patients with atrial fibrillation. RESULTS: Sixty-five patients were included. The majority of the patients were older than >75 (63%), female (69%), and had established HTN (68%). The mean CHA2DS2-VASc score was 4.25 with P-value <0.009. Utilizing the cox proportional-hazards model, the hazard ratios for females, patients with diabetes mellitus, and CHA2DS2-VASc score were statistically significant with P-value < 0.05 and hazard ratios with confidence intervals that did not include 1. The area under the curve of ROC was 0.67, indicating a fair-to-poor marker with regards to the predictive power of CHA2DS2-VASc score for mortality development in this patient population. When examining mortality in patients based on whether or not patients were on anticoagulation, the hazard ratio was 0.36 (CI 0.089) with P < 0.05. The Kaplan-Meier curves demonstrate longer survival and less mortality for patients with atrial fibrillation on anticoagulation. CONCLUSION: The predictive power of the CHA2DS2-VASc score was relatively low. The CHA2DS2-VASc score had a statistically significant hazard ratio, a score >4 had increased mortality. Patients on anticoagulation had less mortality than patients not on anticoagulation.