Preoperative sleep disturbance and postoperative delirium in elderly joint replacement patients: a prospective cohort study.

Abstract

Background: Postoperative delirium (POD) represents a frequent complication among patients undergoing joint replacement surgery. While sleep disturbance is prevalent during the perioperative period, its relationship with POD has not been fully clarified. To this end, the present study was conducted to investigate the association between preoperative sleep disturbance and POD in elderly patients undergoing joint replacement.

Methods: This prospective cohort study recruited 200 patients undergoing elective knee or total hip replacement surgery between April 10th and July 15th, 2025, retrospectively registered with the Chinese Clinical Trial Registry (ChiCTR2500113120) on November 25, 2025. Specifically, preoperative subjective sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) on the day of admission. POD was assessed twice daily using the Chinese version of the 3-Minute diagnostic assessment for delirium based on the Confusion Assessment Method (3D-CAM) within the first postoperative week. Multivariable logistic regression was performed to examine the association between preoperative sleep disturbance and POD, adjusting for age, sex, American Society of Anesthesiologists (ASA) classification, alcohol consumption, smoking,comorbidity, education level, type of anesthesia and PCIA.

Results: Preoperative sleep disturbance was observed in 69 of 200 patients (35%), with POD present in28 patients (14%). Followingmultivariable adjustment, preoperative sleep disturbance was independently associated with the occurrence of POD (OR: 2.84, 95% CI: 1.24-6.50, P = 0.013). The RCS curve revealed a significant positive linear association: as the PSQI score increased, POD risk increased gradually (P for overall = 0.036, P for nonlinear = 0.190). Exploratory subgroup analyses indicated a significant association between preoperative sleep disturbance and POD among patients under 80 years of age, females, patients with a normal BMI, and those with an ASA Ⅱ.

Conclusion: In elderly patients undergoing elective knee or total hip replacement surgery, preoperative sleep disturbance is independently associated with an increased risk of POD.