THE PROGNOSTIC ROLE OF CLINICAL FEATURES AND BIOMARKERS IN PATIENTS HOSPITALIZED WITH CARDIORENAL SYNDROMES

Abstract

Objective: Cardiorenal syndromes (CRS), involving the heart-kidney cross-talk and the activation of neurohumoral and inflammatory pathways, is an entity characterized by high morbidity and mortality. The aim of this study was to evaluate the prognostic role of risk factors and biomarkers in patients hospitalized for CRS. Design and method: In this prospective, observational cohort study, 113 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 = 59): discharged being dialysis-independent, Group 2 (N = 54): death/dialysis dependence at discharge. No major differences were detected in baseline characteristics between the two groups. Group 2 patients used renin-angiotensin-aldosterone system blockers (RAASb) less often (Group 1: 69.5% vs. Group 2: 46.3%, p = 0.01) and more frequently presented with oliguria/anuria (Group 1: 28.8% vs. Group 2: 70.4%, p < 0.001) and any infection (Group 1: 33.9% vs. Group 2: 55.6%, p = 0.02). No dissimilarities were noted in echocardiographic markers. Group 2 patients had significantly lower hemoglobin, serum albumin, bicarbonate, and 25-hydroxy-vitamin D (25OHD). At the same time, N-terminal prohormone brain natriuretic peptide, serum potassium, and parathyroid hormone (PTH) were significantly higher in Group 2 patients (Figure 1). In a multivariate regression analysis, lack of RAASb was independently associated with a 17.7-fold increased risk of death or dialysis dependence at discharge, while the decreasing 25OHD/PTH ratio (beta coefficient -0.01, p = 0.007) and increasing admission serum potassium levels (beta coefficient 0.82, p = 0.03) increased the possibility of facing the composite endpoint. Following a receiver operating characteristic curve analysis, 25OHD/PTH ratio emerged as the most accurate predictor of facing the composite endpoint, with an ideal cutoff of 103.7 (sensitivity 81%, specificity 74%) (Figure 2). Conclusions: Lack of prior RAASb use, high admission serum potassium, and a low 25OHD/PTH ratio are associated with poor prognosis in patients hospitalized for CRS.