Association Between Preoperative Activities of Daily Living and Postoperative Delirium in Elderly Patients Undergoing Non-Cardiac Surgery: A Prospective Cohort Study

Background: Postoperative delirium (POD) is a common complication in elderly surgical patients associated with adverse outcomes. However, the relationship between low preoperative Barthel Index (BI) and POD remains unclear. Purpose: This study investigated the correlation between preoperative BI and POD incidence in elderly patients undergoing non-cardiac surgery. Patients and Methods: This prospective cohort study enrolled 298 patients (≥65 years) undergoing elective non-cardiac surgery under general anesthesia. Preoperative BI assessed activities of daily living (ADL) within 24 hours before surgery. POD was screened twice daily until postoperative day 7 or discharge using the 3-Minute Diagnostic Interview for Confusion Assessment Method-defined Delirium (3D-CAM). Univariate and multivariate logistic regression analyzed associations between BI and POD. Restricted cubic spline (RCS) and two-piecewise linear regression explored non-linearity and identified inflection points. Findings were validated using inverse probability of treatment weighting (IPTW), and BI's incremental predictive value was evaluated by receiver operating characteristic (ROC) curve analysis. Results: POD incidence was 25.8% (77/298). Multivariate analysis showed lower preoperative BI (OR=0.956, 95% CI: 0.940-0.973, p