Perioperative Antibiotic Exposure and Postoperative Delirium in Older Adults Undergoing Elective Non-cardiac Surgery: A Single-center Prospective Cohort Study

This study aimed to characterize the current patterns of perioperative prophylactic antibiotic use and to systematically evaluate the association between different antibiotic classes and the occurrence of POD, thereby providing clinically relevant safety evidence for perioperative antibiotic decision-making and delirium prevention strategies.

Inclusion Criteria: * patients over 65 years old * patients undergoing elective non-cardiac surgery Exclusion Criteria: * older adult patients who had history of psychotic disorders * history of neurological disease * conditions that would make assessments for delirium unreliable * preoperative infection * severe hepatic and renal dysfunction, minor and intermediate clean-incision surgery * missing data exceeding 5%, and no medication records