January 5, 2011Critical Care100 citationsOpen Access
Direct comparison of serial B-type natriuretic peptide and NT-proBNP levels for prediction of short- and long-term outcome in acute decompensated heart failure
Key Result
In patients with acute decompensated heart failure, BNP at 24 hours independently predicted one-year mortality (HR 1.02 per 100 pg/mL increase), with levels declining more rapidly than NT-proBNP in survivors.
Study Design
Type
Cohort (n=171)
Blinding
Single-blind
Multicenter
Yes
Structured PICO
Do serial measurements of BNP and NT-proBNP predict short- and long-term outcomes in patients with acute decompensated heart failure?
P
Population
171 consecutive patients (mean age 80 years, 40% female) presenting to the emergency department with acute decompensated heart failure, followed for 1 year.
E
Exposure
Serial measurement of BNP and NT-proBNP at presentation, 24 hours, 48 hours and at discharge
O
Outcome
One-year all-cause mortalityhard clinical
Main Result
Hazard Ratio: 1.02 (95% CI 1.01–1.04)
p-value: p=0.003
Limitations
- Small sample size to reach statistical significance for the comparison between BNP and NT-proBNP for 30-day all-cause mortality
- Inter-individual heterogeneity regarding doses of nitrates and diuretics applied
- Observational design limits ability to prove patient management could be improved by this monitoring tool
Abstract
INTRODUCTION: Monitoring treatment efficacy and assessing outcome by serial measurements of natriuretic peptides in acute decompensated heart failure (ADHF) patients may help to improve outcome. METHODS: This was a prospective multi-center study of 171 consecutive patients (mean age 80 73-85 years) presenting to the emergency department with ADHF. Measurement of BNP and NT-proBNP was performed at presentation, 24 hours, 48 hours and at discharge. The primary endpoint was one-year all-cause mortality; secondary endpoints were 30-days all-cause mortality and one-year heart failure (HF) readmission. RESULTS: During one-year follow-up, a total of 60 (35%) patients died. BNP and NT-proBNP levels were higher in non-survivors at all time points (all P < 0.001). In survivors, treatment reduced BNP and NT-proBNP levels by more than 50% (P < 0.001), while in non-survivors treatment did not lower BNP and NT-proBNP levels. The area under the ROC curve (AUC) for the prediction of one-year mortality increased during the course of hospitalization for BNP (AUC presentation: 0.67; AUC 24 h: 0.77; AUC 48 h: 0.78; AUC discharge: 0.78) and NT-proBNP (AUC presentation: 0.67; AUC 24 h: 0.73; AUC 48 h: 0.75; AUC discharge: 0.77). In multivariate analysis, BNP at 24 h (1.02 1.01-1.04, P = 0.003), 48 h (1.04 1.02-1.06, P < 0.001) and discharge (1.02 1.01-1.03, P < 0.001) independently predicted one-year mortality, while only pre-discharge NT-proBNP was predictive (1.07 1.01-1.13, P = 0.016). Comparable results could be obtained for the secondary endpoint 30-days mortality but not for one-year HF readmissions. CONCLUSIONS: BNP and NT-proBNP reliably predict one-year mortality in patients with ADHF. Prognostic accuracy of both biomarker increases during the course of hospitalization. In survivors BNP levels decline more rapidly than NT-proBNP levels and thus seem to allow earlier assessment of treatment efficacy. Ability to predict one-year HF readmission was poor for BNP and NT-proBNP. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00514384.