Mortality risk assessment in type 2 cardiorenal syndrome: comparative study

Abstract Background Type 2 cardiorenal syndrome is a serious, life threatening clinical condition, associated with adverse clinical outcomes. Although several prognostic biomarkers have been reported, early and accurate prognosis still remains a challenge. Aims This study was aimed to identify the best prognostic renal markers, to develop and validate an individualized predictive formula for the mortality risk in type 2 cardiorenal patients. Methods A total of 170 hospitalized patients (between 2014 and 2018) were included in this study. Renal function and glomerular filtration rate (GFR) was assessed using the most popular formulas for GFR estimation: the Cockcroft-Gault (CG), the four-variable Simplified Modification of Diet in Renal Disease (sMDRD), CKD-Epidemiology Collaboration (CKD-EPI) based on serum cystatin-C, creatinine and their combination, and the simple cystatin-C formula. All data were used to screen the predictors via univariate and multivariate analyses. A model was developed based on these predictors and validated by internal validation. The model validation comprised discriminative ability determined by the area under the curve (AUC) of receiver operating characteristic (ROC) curve and the predictive accuracy by calibration plots. Results During a mean follow-up of 6 months, 29 (16.2%) deaths were recorded. In an adjusted model, renal biomarkers and estimated glomerular filtration rate showed different prognostic value according to the area under the curve. Area under the ROC curve was 0.58 (95% CI:0.47–0.69, P=0.05) for serum creatinine, 0.67 (95% CI: 0.56–0.79, P