Estimated glomerular filtration rate calculated with the new CKD-EPI-creatinin-Cystatin C equation and long-term prognostic in chronic heart failure

Abstract

Introduction: The correct estimation of renal function may be crucial in assessing prognosis in patients with heart failure (HF). Recently, a new equation for estimation of glomerular filtration rate (eGFR) using combined creatinine and cystatin C levels (CKD-EPI-creat-Cys) has been proposed. Objective: To assess the prognostic role of the eGFR calculated with this new equation in a population of outpatients with HF over a long-term follow-up and to compare it with eGFR calculated with the Cockroft-Gault formula (C-G), recently described as better prognosticator than other routinely used eGFR equations. Results: 879 patients were studied (median age 70.4 years, main etiology of HF ischemic heart disease (52.7%), median LVEF 34%). Both formulas correlated significantly (ICC 0.877 [0.861-0.892]) but distribution of patients along NKF groups were quite different (Kappa value 0.51 [0.785; 0.604]. During a median follow-up period of 3.94 years, 371 patients died. Both formulas (C-G and CKD-EPI-Cr-Cys) showed similar prognostic value according to AUC (0.668 and 0.670 respectively, p=0.72). In Cox regression multivariable analyses (age, sex, NYHA functional class, ischemic etiology, LVEF< HF duration, diabetes, COLD, peripheral artery disease, hemoglobin, sodium and b-blocker and ACEI or ARB treatments) eGFR calculated with both formulas remained significantly associated with death (HR 0.990 [0.983-0.998], p=0.010 for C-G and HR 0.988 [0.983-0.984], p<0.001 for CKD-EPI-Creat-Cys). Figure depicts survival curves according to eGFR subgroups estimated by C-G and CKD-EPI-creat-Cys. Conclusion: The new CKD-EPI-creat-Cys equation was useful for HF risk stratification and showed measurements of performance quite similar to C-G formula regardless of distributing the patients quite differently. (Figure presented).