Nt‐proBNP in haemodialysis patients: A preliminary study

Abstract

Objective. N‐terminal pro‐brain natriuretic peptide (Nt‐proBNP) is a marker of left ventricular function. Although many factors can increase left ventricular dysfunction in haemodialysis patients, the role of Nt‐proBNP is uncertain. Material and methods. Serum concentrations of Nt‐proBNP and troponin T were measured by electrochemiluminescence and C‐reactive protein by immunoturbidimetry in 52 dialysis patients followed‐up for 36 months. Results. Nt‐proBNP correlated (p<0.05) with time on haemodialysis (rho = 0.345), left ventricular mass index (r = 0.596), troponin T level (r = 0.605) and age (r = 0.296). Patients with a history of heart disease showed higher levels of Nt‐proBNP (median; minimum‐maximum ngl/L) (15,571; 1,553–209,451) than those without (4,535; 751–115,078) (p<0.01). Sensitivity and specificity of Nt‐proBNP in the detection of left ventricular dysfunction (ventricular ejection fraction <45 %) were 1.0 and 0.782, respectively. In the univariate analysis, patients with Nt‐proBNP levels ⩾33,314 ng/L, CRP ⩾5 mg/L or troponin T ⩾0.1 µg/L had poorer probabilities of 1‐year, 2‐year and 3‐year survival than patients with lower levels. Unfavourable prognostic factors in the multivariate analysis were CRP >5 mg/L and Tn T >0.1 µg/L. Conclusions. Nt‐proBNP showed good diagnostic performance for detecting left ventricular dysfunction and was an important predictor of mortality in haemodialysis patients in the univariate analysis. In the multivariate analysis, Nt‐proBNP lost its prognostic value, whereas for CRP and Tn T it was maintained.

• C‐reactive protein
• haemodialysis patients
• left ventricular dysfunction
• natriuretic peptides
• Nt‐proBNP
• troponin T