Prediction of Outcome in Subarachnoid Hemorrhage with N-terminal Probrain Natriuretic Peptide (NT-proBNP)

Lee, Young Ju; Baek, Kwang Je; Ki, Woong; Lee, Kyeong Ryong

Abstract

PURPOSE: N-terminal probrain natriuretic peptide (NT-pro-BNP) is elevated in congestive heart failure and myocardial infarction similarly to brain natriuretic peptide (BNP). Serum brain natriuretic peptide (BNP) is elevated after sub-arachnoid hemorrhage (SAH). The aims of this study were to prospectively demonstrate whether NT-pro-BNP is elevated after SAH and to quantify the relationship between NT-pro-BNP levels and patient outcome after SAH.
METHODS
Forty-six consecutive patients with aneurysmal SAH who visited our emergency medical center from March 2006 to August 2006 were prospectively recruited. Patients with histories of myocardial infarction, congestive heart failure and chronic renal failure were excluded from study enrollment. Plasma was collected for NT-pro-BNP and troponin I measurements as soon as possible after enrollment. The accuracy of prediction of outcome was assessed by inhospital mortality.
RESULTS
The mean patient age was 52+/-13 years, and 59% of the patients were women. Troponin I was elevated in 8 (17.4%) patients and NT-pro-BNP was elevated in 14 (30.4%) patients. The NT-pro-BNP level was associated with the Hunt-Hess grade (p=0.00). The median NT-pro-BNP level was 543.8+/-406.3 pg/ml in in-hospital death patients and 131.4+/-91.1 pg/ml in surviving patients (p=0.00). At a cutoff of 300 pg/ml, the sensitivity and specificity of NT-pro-BNP for the prediction of outcome were 66.7% and 92.9%, respectively. By multivariate logistic regression analysis, the NT-pro-BNP was determined to be an independent predictor of in-hospital mortality (odds ratio 26, 95% CI 4.6-148.2, p=0.00).
CONCLUSION
Early after SAH, elevated NT-pro-BNP levels are a strong independent predictor of in-hospital mortality.