Early blood urea nitrogen-albumin ratio as a prognostic marker in severe burn patients: A retrospective clinical study.

Abstract

The blood urea nitrogen-to-albumin ratio (BAR) has been proposed as a prognostic marker in various clinical settings, yet its predictive value in patients with extensive burns remains unclear. This study aimed to explore the potential association between the BAR and the prognosis of patients with extensive burns. We conducted a retrospective, single-center cohort study at the Burn Center of Changhai Hospital, including patients admitted between May 1, 2005, and December 31, 2022. Eligible patients were randomly assigned to a training set and a validation set in a 7:3 ratio. Univariate and multivariate Cox regression analyses were performed to identify mortality-associated factors, including age, sex, burn etiology, total body surface area burned (TBSA), full-thickness burn area (FTBA), blood urea nitrogen, serum creatinine, serum albumin, and BAR. The predictive value of BAR was assessed using receiver operating characteristic (ROC) curves and Kaplan-Meier survival analysis. The model was validated using the internal validation set. A total of 372 patients with extensive burns were included (73.92 % male; 81.99 % flame burns). Age, TBSA, FTBA, inhalation injury, tracheostomy, and BAR were identified as independent predictors of 30-day mortality. The same variables, excluding age, also predicted 60-day mortality. BAR outperformed serum albumin in prognostic accuracy. The area under the receiver operating characteristic curve for 30-day mortality was 0.801 (95 % confidence interval [95 % CI]: 0.729-0.872; sensitivity: 0.750; specificity: 0.728) and for 60-day mortality was 0.801 (95 % CI: 0.734-0.867; sensitivity: 0.714; specificity: 0.731). BAR is an accessible, cost-effective prognostic marker with high predictive accuracy for 30-day and 60-day mortality in patients with extensive burns. It demonstrates superior prognostic utility compared to individual markers and may support risk stratification in burn care.