The changes in NT-proBNP plasma concentrations during dialysis are highly dependent of the dialysis membrane ultrafiltration coefficient.

ABSTRACT

BACKGROUND: NT-proBNP is a powerful marker with diagnostic and pronostic value for heart failure. It is of particular interest in patients with end-stage renal disease who are at high risk for heart failure. The aim of this study was to investigate the effect of hemodialysis on plasma NT-proBNP concentrations. METHODS: NT-proBNP concentration was measured in 67 patients before and after hemodialysis. RESULTS: In the 20 patients dialyzed with a membrane whose ultrafiltration coefficient was below or equal to12, NT-proBNP concentration was comparable after and before dialysis (16611+/-21024 vs. 15216+/-19027 pg/ml, NS). At the opposite, in the 47 patients dialyzed with a membrane whose ultrafiltration coefficient was above or equal to 40, NT proBNP concentration was 35% lower after dialysis compared to before dialysis (11983+/-21819 vs. 18574+/-31862 pg/ml, p<0.0001). CONCLUSIONS: In patients dialyzed with a membrane whose ultrafiltration coefficient is high, dialysis is likely to decrease results by one third. Thus sampling blood before dialysis in hemodialyzed patients appears as the best time to stratify the cardiovascular risk in these patients.