Comparative analysis of plasma BNP and NT-proBNP levels, and NT-proBNP/BNP ratio in patients with chronic kidney disease

Both B-type natriuretic peptide (BNP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) are clinically used for diagnosing and monitoring heart failure. However, their levels are influenced by several factors, and their impacts on chronic kidney disease (CKD) patients remain unclear. This study included 1036 patients who visited the Nephrology division at our hospital between 2014 and 2015. Plasma BNP, NT-proBNP levels and the BNP/NT-proBNP ratio were measured at each CKD stage, and their correlation with clinical factors were analyzed. This study included 1037 patients with stage 1 to stage 5D CKD (CKD 1-2, n = 114; CKD 3, n = 256; CKD 4, n = 266; CKD 5, n = 298; CKD 5D, n = 102). Levels of plasma BNP and NT-proBNP levels and the NT-proBNP/BNP ratio increased, and the correlation between BNP and NT-proBNP levels weakened with declining kidney function. Although various clinical factors were found to be significantly correlated with these parameters, multivariate analysis showed that male gender and hemoglobin, phosphate, and parathyroid hormone levels were significantly correlated with both plasma BNP and NT-proBNP levels. Notably, a higher NT-proBNP/BNP ratio was significantly associated with increased cardiovascular events in patients with CKD stages 4 and 5. As plasma BNP and NT-proBNP levels are influenced by various factors in patients with CKD, careful interpretation of these parameters is essential. In patients with advanced-stage CKD, the NT-proBNP/BNP ratio may be a useful predictor of CVD development.