Prognostic value of plasma amino-terminal pro-brain natriuretic peptide in a large, representative ICU population
© BioMed Central Ltd 2008
Published: 13 March 2008
We sought to determine whether amino-terminal pro-brain natriuretic peptide (NT-proBNP) predicts ICU outcome in a representative cohort of mechanically ventilated, critically ill patients.
A total of 234 consecutive patients (109 men – median age: 60 years) with a wide range of admitting diagnoses (medical, surgical, and multiple trauma cases) were included in this prospective study that was conducted in two ICUs of tertiary hospitals over an 18-month period. The following data were recorded upon ICU entry: age, sex, admitting diagnosis, severity of critical illness according to the APACHE II score, degree of organ dysfunction quantified by the SOFA score and the presence of sepsis using established criteria. Exclusion criteria included chronic heart failure defined by a left ventricular ejection fraction <50% on admission echocardiography, and pre-existent renal insufficiency (history of serum creatinine >1.8 mg/dl before ICU entry). The primary end point was ICU outcome.
Nonsurvivors (n = 98) had significantly higher NT-proBNP levels on ICU admission (2,074 vs 283 pg/ml, P < 0.001), on day 1 (2,197 vs 221 pg/ml, P < 0.001) and on day 2 (2,726 vs 139 pg/ml, P < 0.001) than survivors (n = 135). Receiver operated characteristics (ROC) analysis showed that the area under the ROC curve with regard to ICU mortality prediction was 0.70 for APACHE II and 0.77 for admission NT-proBNP. The cutoff value in admission NT-proBNP that best predicted outcome was 941 pg/ml. Multiple logistic regression analysis revealed that APACHE II score (OR = 1.06, 95% CI = 1.01–1.11, P = 0.007) and the best cutoff point in NT-proBNP (OR = 7.74, 95% CI = 4.00–14.9, P < 0.0001) independently predicted ICU outcome.
In a representative mixed ICU population, non-survivors have consistently higher NT-proBNP levels compared with survivors. Admission NT-proBNP concentrations provide independent prognostic information for ICU mortality.
This article is published under license to BioMed Central Ltd.