Lactate dehydrogenase-to-albumin ratio as a novel prognostic biomarker for 28-day mortality in thoracic trauma: a single-center retrospective cohort study.

BACKGROUND/AIM: Thoracic trauma accounts for approximately 25% of all trauma-related deaths and remains a significant public health challenge. Early identification of high-risk patients is essential for improving clinical outcomes. The present study evaluates the prognostic value of the lactate dehydrogenase-to-albumin ratio (LDAR) in predicting 28-day mortality in patients with thoracic trauma. MATERIALS AND METHODS: This retrospective observational study was conducted at a Level 1 trauma center between September 2022 and February 2025, and included adult patients presenting with thoracic trauma who underwent thoracic computed tomography. Demographic characteristics, clinical parameters, laboratory values, and 28-day mortality were analyzed. Receiver operating characteristic (ROC) curve analysis was performed to assess the discriminatory power of LDAR and other biomarkers, while multivariate logistic regression was used to identify independent predictors of mortality. RESULTS: A total of 493 patients were included in the study, 46 of whom (9.3%) died within 28 days. White blood cell count, lactate dehydrogenase, lactate, lactate/albumin ratio, LDAR, and Shock Index were statistically higher in the nonsurvivor group, and albumin, pH, and HCO3 levels were lower (p < 0.001). Furthermore, LDAR was significantly higher in the nonsurvivor group when compared to the survivors (13.51 vs. 7.48, p < 0.001). ROC analysis demonstrated that LDAR had excellent discriminatory power for predicting mortality (AUC = 0.854; 95% CI: 0.795-0.914), with an optimal cutoff value of 11.56 yielding 71.7% sensitivity and 91.5% specificity. CONCLUSION: LDAR is a reliable and independent prognostic biomarker for predicting in-hospital mortality in patients with thoracic trauma. As a ratio derived from routine laboratory parameters without additional cost, LDAR offers a practical tool for rapid risk stratification and triage optimization in emergency settings. Prospective multicenter studies are warranted to validate these findings.