Abstract
BACKGROUND: The albumin-bilirubin (ALBI) score is created to estimate liver dysfunction and then extended to more general applications. Nonetheless, the effectiveness of ALBI score in forecasting adverse outcomes in patients after cardiac surgery remains unexplored. The purpose of this study was to explore the association of the ALBI score with postoperative delirium (POD) and in-hospital mortality in patients following cardiac surgery. METHODS: Data of patients who underwent cardiac surgery and had an intensive care unit stay after surgery were extracted from the MIMIC-IV and eICU-CRD databases. The links of ALBI score with POD and in-hospital mortality were examined by multivariate logistic regression models, restricted cubic spline (RCS), and subgroup analyses. Receiver operator characteristic (ROC) curves were plotted to check the predictive power of ALBI. RESULTS: 4940 patients were enrolled and categorized into three groups based on the ALBI quartiles: <-2.52, -2.52 to -1.68, and > -1.68. Patients in the T3 quartile had greatly higher risks of POD (OR [95%CI], 2.429 [1.929, 3.067], P < 0.001) and in-hospital mortality (2.656 [1.717, 4.213], P < 0.001) than T1 cohorts in the completely adjusted model. Each unit increase in ALBI was linked to a 72.7% increase in POD risk (1.727 [1.511, 1.975]. P < 0.001) and a 155.3% increase in in-hospital mortality risk (2.553 [1.995, 3.282]. P < 0.001). RCS revealed nearly linear links of ALBI with POD and in-hospital mortality. The areas under the ROC curve were 0.590 (95% CI: 0.570–0.610) and 0.717 (0.685–0.749), respectively. In subgroup analysis, notable interactions were found in the age (p for interaction = 0.039), gender (p for interaction = 0.035), and congestive heart failure (p for interaction = 0.028). CONCLUSIONS: ABLI score is a pivotal predictor of POD and in-hospital mortality in patients undergoing cardiac surgery. ABLI score may have crucial implications for risk stratification and treatment of individuals after cardiac surgery. CLINICAL TRIAL NUMBER: Not applicable. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12893-025-03440-4.