Hemoglobin and N-terminal pro-brain natriuretic peptide: Independent and synergistic predictors of mortality in patients with acute heart failure. Results from the International Collaborative of NT-proBNP (ICON) Study

Abstract

Background: Hemoglobin and amino-terminal pro-brain natriuretic peptide (NT-proBNP) are both independent predictors of mortality in patients with chronic HF. Their combined predictive power for mortality in the setting of acute HF is uncertain. Methods: In an international prospective cohort design, we evaluated the relationships between hemoglobin, NT-proBNP, and 60-day mortality in 690 patients with acute HF. Results: The median hemoglobin for the entire cohort was 13.0 g/dL (interquartile range 11.6-14.3). The WHO criterion for anemia was met by 44% (n = 305). The 60-day mortality rate for anemic patients was 16.4% vs. 8.8% in non-anemic patients (p < 0.001). Anemia was an independent predictor of short-term mortality (OR = 1.72, 95% CI = 1.05-2.80, p = 0.03), as was a NT-proBNP concentration > 5180 pg/mL (OR = 2.32, 95% CI = 1.36-3.94 p = 0.002). Consideration of four risk groups: not anemic/low NT-proBNP (reference group, n = 220), anemic/low NT-proBNP (n = 152), not anemic/high NT-proBNP (n = 165), and anemic/high NT-proBNP (n = 153) revealed respective 60-day mortality rates of 5.0% (referent), 9.2% (OR = 1.93, 95% CI = 0.85-4.36; p = 0.12), 13.9% (OR =3 .07, 95% CI = 1.45-6.50, p = 0.003), and 23.5% (OR = 5.84, 95% CI = 2.87-11.89, p < 0.001). Conclusions: Anemia was common in this cohort of subjects with acute HF and was related to adverse short-term outcome. Integrated use of hemoglobin and NT-proBNP measurements provides powerful additive information and is superior to the use of either in isolation. © 2007 Elsevier B.V. All rights reserved.