Prognostic significance of the blood urea nitrogen-to-serum albumin ratio in patients with septic shock.

The blood urea nitrogen-to-serum albumin ratio (BAR) has been linked to clinical outcomes in multiple critical illnesses; however, its prognostic value in patients with septic shock remains inconclusive. The present retrospective observational study involved 120 patients with septic shock, who were classified into a survivor group (n=97) and a non-survivor group (n=23) based on discharge outcomes. Within 24 h of ICU admission, important clinical and laboratory data were collected and compared between the two groups. Multivariate logistic regression analysis identified BAR [odds ratio (OR)=1.052; 95% confidence interval (CI):1.014-1.117; P=0.012] and the Acute Physiology and Chronic Health Evaluation II (APACHE II; OR=1.096; 95% CI:1.014-1.185; P=0.030) as independent risk factors for in-hospital mortality in these patients. Receiver operating characteristic (ROC) curve analysis showed that the area under the curve (AUC) of BAR for predicting in-hospital mortality was 0.707. At the optimal cutoff value of 13.62, BAR had a sensitivity of 73.9% and a specificity of 63.9%. Further, the AUC of the multivariable model [including BAR, diastolic blood pressure (DBP), APACHE II, and partial pressure of carbon dioxide (PCO2)] was 0.859 (95% CI:0.778-0.939; P<0.001); the optimal cutoff value was 0.154; the sensitivity was 87% and the specificity was 74.2%, which was markedly improved over single BAR or APACHE II. Therefore, BAR emerged as a valid independent predictor of in-hospital mortality in patients with septic shock and may serve as a simple, readily accessible biomarker for the early risk stratification in this patient population. The BAR model incorporating DBP, APACHE II and PCO2 demonstrated high discrimination and stratification efficiency for patient mortality risk.