Anaemia and renal dysfunction are independently associated with BNP and NT-proBNP levels in patients with heart failure

Background: Anaemia may affect 13-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) levels, but this has not been well described in heart failure (1417) patients without the exclusion of patients with renal dysfunction. Aims: To study the influence of both anaemia and renal function on BNP and NT-proBNP levels in a large group of hospitalised HF patients. Methods and results: We studied 541 patients hospitalised for HF (mean age 71 +/- 11 years, 62% male, and left ventricular ejection fraction 0.33 +/- 0.14). Of these patients, 30% (n= 159) were anaemic (women: Hb < 7.5 mmol/l, men: Hb < 8.1 mmol/1). Of the 159 anaemic patients, 73% had renal dysfunction (eGFR < 60 ml/min/1.73 m(2)) and of the non-anaemic patients, 57% had renal dysfunction. BNP and NT-proBNP levels were measured in all patients before discharge. In multivariable analyses both plasma haemoglobin and eGFR were independently related to the levels of BNP and NT-proBNP (standardised beta's of -0.16, -0.14 [BNP] and -0.19, -0.26 [NT-proBNP] respectively, P-values < 0.01). Conclusion: Anaemia and renal dysfunction are related to increased BNP and NT-proBNP levels, independent of the severity of HE These results indicate that both anaemia and renal dysfunction should be taken into consideration during the interpretation of BNP and NT-proBNP levels in HF patients. (c) 2007 European Society of Cardiology. Published by Elsevier B.V. All rights reserved.