Prognostic Significance of Risk Factors and Biomarkers in Patients Hospitalized for Cardiorenal Syndromes: A Pilot Study

Background Cardiorenal syndromes (CRS), involving the heart-kidney cross-talk and the activation of neurohumoral and inflammatory pathways, are an entity characterized by high morbidity and mortality. Objective To evaluate the prognostic role of risk factors and biomarkers in patients hospitalized for CRS. Methods In this observational cohort study, 100 consecutive patients hospitalized for CRS were enrolled. Socio-demographic characteristics, personal medical history, and prior medication use were recorded upon admission, and echocardiography was performed. Moreover, an array of blood markers were measured. The endpoint of interest was a composite of death or dialysis dependence at discharge. Results Patients were classified into two groups; Group 1 (N= 52): discharged being dialysis-independent, Group 2 (N=48): death/dialysis dependence at discharge. No significant differences were detected in baseline characteristics between the two groups. Group 2 patients used renin-angiotensin-aldosterone system blockers (RAASb) less often and more frequently presented with oliguria/anuria. Group 2 patients had significantly lower hemoglobin, serum albumin, and 25-hydroxy-vitamin D (25(OH)D). At the same time, serum phosphate, potassium, and parathyroid hormone (PTH) were significantly higher in Group 2 patients. In a multivariate regression analysis, lack of prior RAASb and lower 25(OH)D levels were independently associated with an increased risk of death or dialysis dependence at discharge. 25(OH)D/PTH ratio was the most accurate predictor of the composite endpoint (Sensitivity: 79.4%, Specificity: 70.4%). Conclusion Lack of prior RAASb use, high PTH, low 25(OH)D levels, and low 25(OH)D/PTH ratio are associated with a poor prognosis in patients hospitalized for CRS.