Utility of amino-terminal pro-brain natriuretic peptide testing for prediction of 1-year mortality in patients with dyspnea treated in the emergency department.
BACKGROUND
Amino-terminal pro-brain natriuretic peptide (NT-proBNP) is useful for diagnosis and triage of patients with dyspnea, but its role for predicting outcomes in such patients remains undefined.


METHODS
A total of 599 breathless patients treated in the emergency department were prospectively enrolled, and a sample of blood was obtained for NT-proBNP measurements. After 1 year, the vital status of each patient was ascertained, and the association between NT-proBNP values at presentation and mortality was assessed.


RESULTS
At 1 year, 91 patients (15.2%) had died. Median NT-proBNP concentrations at presentation among decedents were significantly higher than those of survivors (3277 vs 299 pg/mL; P<.001). The optimal NT-proBNP cut point for predicting 1-year mortality was 986 pg/mL. In a multivariable model, an NT-proBNP concentration greater than 986 pg/mL at presentation was the single strongest predictor of death at 1 year (hazard ratio [HR], 2.88; 95% confidence interval, 1.64-5.06; P<.001), independent of a diagnosis of heart failure. Other factors associated with death included age (by decade; HR, 1.20), heart rate (by decile; HR, 1.13), urea nitrogen level (by decile; HR, 1.20), systolic blood pressure less than 100 mm Hg (HR, 1.94), heart murmur (HR, 1.92), and New York Heart Association classification (HR, 1.38 for each increase in class). The NT-proBNP concentration alone had an area under the receiver operating characteristic curve (AUC) of 0.76 for predicting mortality; the other significant covariates combined had an AUC of 0.80. The final model for predicting death, combining NT-proBNP with other covariates associated with mortality, had a superior AUC of 0.82.


CONCLUSIONS
In addition to assisting in emergency department diagnosis and triage, NT-proBNP concentrations at presentation are strongly predictive of 1-year mortality in dyspneic patients.
Januzzi
James L
JL
Department of Internal Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, USA. JJanuzzi@partners.org
Sakhuja
Rahul
R
O'donoghue
Michelle
M
Baggish
Aaron L
AL
Anwaruddin
Saif
S
Chae
Claudia U
CU
Cameron
Renee
R
Krauser
Daniel G
DG
Tung
Roderick
R
Camargo
Carlos A
CA
Lloyd-Jones
Donald M
DM
D000367:Age Factors; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure; D001806:Blood Urea Nitrogen; D004417:Dyspnea / Q000097:blood* / Q000401:mortality*; D004636:Emergency Service, Hospital; D005260:Female; D006333:Heart Failure / Q000145:classification / Q000401:mortality*; D006337:Heart Murmurs / Q000401:mortality; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D011446:Prospective Studies; D012372:ROC Curve; D013318:Stroke Volume; D013599:Systole; D014481:United States / Q000453:epidemiology
D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain