Prognostic Significance of Asymptomatic Brain Natriuretic Peptide Elevation at Nephrology Referral in Patients with Chronic Kidney Disease

Abstract

Background: It is unclear whether asymptomatic elevation of brain natriuretic peptide (BNP) is associated with cardiovascular events (CVEs) or heart failure (HF) in predialysis chronic kidney disease (CKD) patients. Methods: We measured BNP in 482 asymptomatic predialysis patients with CKD stages 2–5 at nephrology referral between August 2004 and October 2010, and followed them prospectively to investigate the prognostic significance of BNP using Cox models and receiver operating characteristic (ROC) analyses. The primary composite end point was the time to death or the first nonfatal CVEs. Secondary end points included CVEs including sudden death, HF and all-cause death. Results: The median age was 67 years (male, 67.4%; diabetic nephropathy, 33.4%), and estimated glomerular filtration rate was 20.1 mL/min/1.73 m². The primary end point occurred in 92 patients. CVEs including sudden death, HF and all-cause death occurred in 66, 35, and 54 patients, respectively during a median follow-up period of 37.7 months. Multivariate analyses showed that BNP level was significantly associated with the primary end point (hazard ratio [HR] 1.241; 95% CI 1.020–1.511; p = 0.031), CVEs (HR 1.337; 95% CI 1.067–1.675; p = 0.012) and HF (HR 1.489; 95% CI 1.059–2.091; p = 0.022), but not associated with all-cause death (HR 1.081; 95% CI 0.829–1.410; p = 0.565). The ROC curves showed that the optimal predictive BNP levels for the primary end point, CVEs and HF were 92.5, 127.0, and 274.6 (pg/mL) respectively. Conclusion: Asymptomatic elevation of BNP is strongly predictive for CVEs and HF, which might help to integrate cardio-renal risk stratification in predialysis CKD patients.

Chronic Kidney Disease and Heart Failure–Everyday Diagnostic Challenges

“…Moreover, in patients with stage 4-5 CKD, a BNP concentration >157 pg/mL was identified as an independent risk factor for a cardiovascular event; however, the sensitivity and specificity were only 65% and 56%, respectively [28]. It has also been shown that, in patients with end-stage renal failure, but without clinical symptoms of HF, the detection of BNP levels >150 pg/mL before starting renal replacement therapy was an independent risk factor for overt HF [29].…”

Cardiovascular Determinants of Mortality in Advanced Chronic Kidney Disease

“…Brain natriuretic peptide has been shown to be associated with a composite end point of time to death or the 1st cardiovascular event but not with all-cause mortality in CKD [13]. In The African American Study of Kidney Disease and Hypertension, proBNP was associated with cardiovascular events and cardiovascular mortality in 994 patients with eGFR 20–65 mL/min/1.73 m 2 , but not with all-cause mortality [30].…”

“…Biomarkers such as troponin T (TnT), N-terminal pro-B-type natriuretic peptide (proBNP), high-sensitivity C-reactive protein (CRP), interleukin-6, and serum albumin have been studied as prognostic factors in CKD with mixed results. Previous studies have shown an association between TnT, proBNP, and cardiovascular events and death and between serum albumin and all-cause mortality in CKD patients [11-13]. However, cardiac biomarkers have not been associated with all-cause mortality in previous studies [13, 14].…”

“…Previous studies have shown an association between TnT, proBNP, and cardiovascular events and death and between serum albumin and all-cause mortality in CKD patients [11-13]. However, cardiac biomarkers have not been associated with all-cause mortality in previous studies [13, 14]. Echocardiographic indices become altered with advancing CKD, and attenuated cardiac systolic [15] and diastolic functions [16] have been associated with mortality in maintenance dialysis patients and advanced CKD without dialysis [17].…”