N-terminal Pro-Brain-type Natriuretic Peptide as a Prognostic Factor in Severe Sepsis and Septic Shock

Bae, Kwang Soo; Jo, You Hwan; Kim, Kyuseok; Lee, Jae Hyuk; Park, Hyun Mi; Rhee, Joong Eui

Abstract

PURPOSE
This study was performed to evaluate whether N-terminal pro-brain-type natriuretic peptide (NT-proBNP) could predict 28-day mortality in patients with severe sepsis and septic shock.
METHODS
We performed a retrospective analysis of prospectively collected data from patients with severe sepsis and septic shock. Patients' demographic data, comorbidities, blood test results (including NT-proBNP concentration), and Acute Physiology and Chronic Health Evaluation (APACHE) II scores were compared between 28-day survivors and nonsurvivors. NT-proBNP levels were categorized into quartiles by their concentration (< or =600, 601 to 2,000, 2,001 to 6,000, and >6,000 pg/ml). Multivariate Cox proportional hazard regression analysis was performed to identify the predictors of mortality during a 28-day follow-up period.
RESULTS
Out of 349 patients, 117(33.5%) died. NT-proBNP concentrations were significantly higher in nonsurvivors compared to survivors (median 4,630 [IQR, 1,876-10,582] vs. 1,552 [IQR, 440-4,064] pg/ml, respectively, p<0.01). The mortality rate increased with increasing NT-proBNP concentrations; patients with NT-proBNP < or =600, 601 to 2,000, 2,001 to 6,000, and >6,000 pg/ml were 12.9%, 26.1%, 39.8%, and 51.1%, respectively. By Cox proportional hazards analysis, compared to patients with the lowest NT-proBNP levels (< or =600 pg/ml), patients in groups with higher NT-proBNP levels were more associated with 28-day mortality; 601 to 2,000 pg/ml (hazard ratio [HR], 1.15; 95% CI, 0.50-2.63); 2,001 to 6,000 pg/ml (HR, 2.10; 95% CI, 1.05-4.81); >600 pg/ml (HR, 2.30; 95% CI, 1.15-6.14).
CONCLUSION
NT-proBNP is an independent prognostic factor for 28-day mortality in patients with severe sepsis and septic shock.