Are BNP Levels Meaningful in Patients with Chronic Renal Failure?

B-type natriuretic peptide (BNP) levels are elevated in many patients with chronic renal failure (CRF). Is elevation caused by renal failure itself, or is it mediated by cardiac dysfunction? To address this question, researchers in Japan measured BNP levels and performed echocardiography in 103 non-dialysis-dependent CRF patients (mean serum creatinine, 4.9 mg/dL) and in 60 hypertensive controls without CRF. Patients with left ventricular (LV) ejection fractions less than 40% or clinical histories of heart failure were excluded.

The mean BNP level was higher in CRF patients than in controls (162 vs. 28 pg/mL). In multivariable analysis of the CRF group, elevated BNP levels were associated independently with older age, low hemoglobin level, a…