Abstract 10128: NT-pro C-type Natriuretic Peptide is a Novel Urinary Biomarker with Prognostic Value in Hospitalized Heart Failure Patients Independent of Glomerular Filtration Rate
Background: The relative utility of novel renal biomarkers in diagnosis or risk stratification in hospitalized heart failure (HHF) patients remains poorly defined. C-type natriuretic peptide (CNP) has been identified in renal tubular cells and in urine. Urinary CNP is increased in diseases such as nephrotic syndrome, in association with elevated renal production and structural changes, but its excretion and clinical significance in HHF is unknown. We sought to compare the clinical utility of urinary biomarkers KIM-1 and NGAL with the novel biomarker CNP for diagnosis and prediction of adverse outcomes in HHF patients.
Methods: Twenty-four hour urine excretion of NGAL, KIM-1, NT-proCNP and CNP-22, and serum NT-proBNP was assessed in 59 HHF patients (mean age 70±10y, 59% male, 32% ischemic) and 20 healthy controls (53±6y, 50% male). Mean follow-up was 175 days. Three primary endpoints were studied: mortality, time to first non-elective rehospitalization/death, and time to first CV rehospitalization/death.
Results: HHF patients had higher serum NT-proBNP and lower GFR values than controls (p<0.0001). Median KIM-1 excretion was significantly higher in HHF patients than controls (38.6±18.9 vs. 18.5±3.2ng/h; p=0.005). NT-proCNP and CNP-22 excretion showed an increased trend in HHF (p=0.9); NGAL excretion was lower in HHF than controls (p=0.2). HHF mortality rate was 15.3%, all-cause rehospitalization/death rate was 45.8% and CV rehospitalization/death rate was 30.5%. NT-proCNP was the only urinary biomarker significantly predictive of mortality (HR 2.02, 95%CI 1.10-3.59, p=0.02), all-cause rehospitalization/death (HR 1.62, 95%CI 1.12-2.30, p=0.01) and CV rehospitalization/death (HR 1.83, 95%CI 1.17-2.79, p=0.008). Its predictive power increased by adjusting for age, GFR and/or serum NT-proBNP. NT-proCNP excretion was a stronger predictor of all endpoints than serum NT-proBNP in this cohort.
Conclusions: HHF diagnosis is associated with elevated KIM-1 excretion, while prognosis significantly correlated with NT-proCNP excretion. Moreover, urinary NT-proCNP offered incremental predictive value to serum NT-proBNP independent of GFR. Further prospective study of urinary NT-proCNP is warranted to explore its clinical use in human HF.
- © 2011 by American Heart Association, Inc.