Efficacy of N-terminal pro-brain natriuretic peptide digit number for screening of cardiac disease in new haemodialysis patients

Aim The usefulness of the absolute N-terminal pro-brain natriuretic peptide (NT-ProBNP) concentration and its digit number for screening for cardiac disease was explored in new haemodialysis patients. Methods A cross-sectional study involving 71 (68 +/- 14 years, 83% male) new dialysis patients was conducted. Receiver operator characteristic curve analysis was performed to identify the cutoff level of NT-proBNP for identifying cardiac disease at the start of dialysis. Results The median NT-proBNP concentration was 6576pg/mL just before the first dialysis session and its mean digit number was 4.3 +/- 0.6. Overall, 67%, 52%, 9% and 35% of patients had left ventricular (LV) hypertrophy, LV dilatation, systolic dysfunction and significant coronary artery disease, respectively. NT-proBNP levels of about 6000, 10000 and 14000pg/mL were the best cutoff levels for the diagnosis of coronary artery disease (AUC, 0.754; P<0.001), LV systolic dysfunction (area under the curve (AUC), 0.765, P=0.001) and LV dilatation (AUC, 0.685, P=0.008), respectively. Interestingly, 4.5 was the best digit number cutoff for all cardiac abnormalities. These findings suggest that a digit number of 5 or more means a potentially high risk for cardiovascular disease and a digit number of 3 or less means a relatively low risk. Conclusions The NT-proBNP concentration just before the first dialysis session is a useful tool for screening for cardiac abnormalities. Considering the wide variation of the NT-proBNP cutoff levels depending on each cardiac abnormality, the digit number could be potentially easier to use for initial risk stratification for cardiac disease in new dialysis patients.