Abstract: Objective To evaluate the significance of N- terminal pro- brain natriuretic peptide (NTproBNP) changes after a hemodialysis session in the assessment of body fluid distribution by comparing these changes with the values from whole-body bioimpedance spectroscopy in maintenance hemodialysis (MHD)patients. Method Whole-body bioimpedance spectroscopy and serum NT-proBNP were measured before and after hemodialysis sessions in 84 MHD patients. Body fluid content and distribution calculated from whole- body bioimpedance spectroscopy and the changes of NT- proBNP were compared in these patients. Results Before hemodialysis, serum NT- proBNP was insignificantly correlated with total body water (TBW), extracellular water (ECW), intracellular water (ICW) and ECW/TBW. After hemodialysis, serum NTproBNP was positively correlated with ECW/TBW (r=0.251, P=0.025), and negatively correlated with ICW (r=-2.333, P=0.037). Correlation analyses also demonstrated that the changes of serum NT-proBNP after hemodialysis were negatively correlated with ECW (r=-0.235, P=0.036), ECW/TBW (r=-0.252, P=0.024) and ECW/ICW (r=-0.228, P=0.042), but had no correlations with TBW (r = -0.121, P = 0.284) and ICW (r = 0.018, P = 0.871). Conclusion The changes of serum NT-proBNP after hemodialysis were comparable with the changes of water distribution after hemodialysis, which may provide a new approach for the evaluation of volume overload in MHD patients.

Key words: multi-frequency bioimpedance analysis, N-terminal pro-brain natriuretic peptide, difference, hemodialysis