Risk Factors for Postoperative Delirium in Older Adults Undergoing Major Orthopedic Surgery: A Systematic Review and Meta-Analysis

Purpose: We aimed to identify the risk factors for postoperative delirium (POD) in adults undergoing orthopedic surgery and review evidence-based prevention strategies. Methods: We conducted a systematic review and meta-analysis of studies published between 2014 and 2024, searching multiple databases. Fifty studies involving 1,247,832 patients met the inclusion criteria. We calculated the pooled odds ratio (OR) values of various risk factors for POD. Results: The pooled incidence of POD was 23.4%. The significant non-modifiable risk factors included dementia (OR 24.85), a history of stroke (OR 14.61), and age ≥80 years (OR 4.73). The key modifiable risk factors were use of sedative-hypnotics (OR 6.42), depression (OR 4.98), and polypharmacy (OR 2.34). Undergoing general anesthesia and longer surgical duration also increased the risk of POD. Conclusions: POD is a common complication in orthopedic surgery and is associated with modifiable and non-modifiable risk factors. The use of risk assessment models and multicomponent prevention strategies focusing on medication optimization, perioperative care, and environmental support is recommended to mitigate the risk of POD.