P4747Impact of different estimates of renal function on cardiovascular mortality and major bleeding in patients with atrial fibrillation on oral anticoagulation

Abstract Background Renal dysfunction is associated with increased risk of cardiovascular events in atrial fibrillation (AF). Estimated glomerular filtration rate (eGFR) can be calculated by different equations based on creatinine or cystatin C. We compared different methods of assessing eGFR and their association with cardiovascular (CV) death and major bleeding in 14,980 AF patients in the ARISTOTLE trial. Methods eGFR was calculated using equations based on creatinine (Cockcroft-Gault, MDRD, and CKD-EPI) and/or cystatin C (CKD-EPIcys and CKD-EPIcys+crea). In total five eGFR equations as well as a model based on the variables within the equations were assessed. Associations were evaluated by Spearman correlation, and discriminatory ability for CV-death and major bleeding by Harrell's c-index. Results Median age was 70.0 years, and 35.6% were women. Median eGFR (mL/min) were: Cockcroft-Gault 74.1, MDRD 66.5, CKD-EPI 68.5, CKD-EPIcys 74.2, and CKD-EPIcys+crea 72.6. Correlation ranged from 0.49 (Cockroft-Gault and CKD-EPIcys) to 0.99 (MDRD and CKD-EPI). Among the eGFR equations, those based on cystatin C yielded the highest c-indices for CV-death and major bleeding, 0.628 (CKD-EPIcys) and 0.612 (CKD-EPIcys+crea), respectively. A model based on the variables within the eGFR equations (age, sex, weight, creatinine, and cystatin C) yielded the highest discriminatory value for both outcomes, 0.673 and 0.656, respectively. Figure 1 Conclusions In patients with AF on anticoagulation, correlation between eGFR methods varied greatly. Cystatin C-based eGFR seem to provide the most robust balance in reflecting the risk of death and bleeding. However, a model based on the individual variables within the eGFR equations provided the highest discriminatory value. Acknowledgement/Funding The ARISTOTLE trial was funded by Bristol-Myers Squibb, Co Princeton, NJ and Pfizer Inc., New York, NY.