Investigation of the Relationship Between Serum Uric Acid-to-Albumin Ratio and 28-Day Mortality in Patients With and Without Acute Kidney Injury.

Background: Acute kidney injury (AKI) is a significant concern in critically ill patients, with mortality and morbidity implications. The serum uric acid-to-albumin ratio has been proposed as a potential prognostic marker for patients with and without AKI. This study aimed to investigate the relationship between this ratio and 28-day mortality in these patient groups. Methods: A retrospective study was conducted on critically ill patients aged over 18, hospitalized in the internal medicine ICU at Osmangazi University, Eskisehir, Turkey, from May 2020 to November 2021. Patients were categorized based on the presence or absence of AKI. The primary outcome was 28-day mortality. The serum uric acid-to-albumin ratio was calculated, and its prognostic value was assessed using Receiver Operating Curve (ROC) analysis. Results: Of the 1,016 patients, 449 had AKI. The mean age was 67.1 ± 15.27 years, with 53.9% being male. The serum uric acid-to-albumin ratio was found to have significant prognostic value in predicting 28-day mortality in both groups. In the overall study group, a ratio of 2.32 mg/g predicted 28-day mortality with 71.1% specificity and 58.3% sensitivity. For patients with AKI, a ratio of 3.59 mg/g predicted mortality with 85.3% specificity and 44% sensitivity. For those without AKI, a ratio of 2.28 mg/g predicted mortality with 84.1% specificity and 39.3% sensitivity. Conclusion: The serum uric acid-to-albumin ratio is a valuable prognostic tool for predicting 28-day mortality in critically ill patients, irrespective of AKI status. Incorporating this low-cost biomarker into scoring systems could enhance patient management and outcome predictions.