NT-pro-BNP predicts worsening renal function in patients with chronic systolic heart failure

Background: Worsening renal function (WRF) is frequently observed in patients with heart failure and is associated with worse outcome. The aim of this study was to examine the association of the cardiac serum marker N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) and WRF. Methods: A total of 125 consecutive patients of a tertiary care outpatient clinic for heart failure prospectively underwent evaluation of renal function every 6 months. The association of baseline NT-pro-BNP with WRF was analysed during a follow up of 18 months. Results: Twenty-eight (22.4%) patients developed WRF (increase in serum creatinine >= 0.3 mg/dL). Patients with WRF (2870 pg/mL, interquartile range (IQR) 1063-4765) had significantly higher baseline NT-pro-BNP values than patients without WRF (547 pg/mL, IQR 173-1454). The risk for WRF increased by 4.0 (95% CI 2.1-7.5) for each standard deviation of log NT-pro-BNP. In multivariable analysis including age, baseline renal function, ejection fraction, New York Heart Association class and diuretic dose, only NT-pro-BNP and diabetes were independent predictors of WRF. At a cut-off level of 696 pg/mL, NT-pro-BNP showed a sensitivity of 92.9% and a negative predictive value of 96.4% for WRF. Conclusion: NT-pro-BNP is a strong independent predictor of WRF within 18 months in patients with systolic heart failure with a high negative predictive value. Further studies are needed to evaluate reno-protective strategies in patients with elevated NT-pro-BNP.