OBJECTIVE: To compare the effects of general anesthesia (GA) and spinal anesthesia (SA) on postoperative delirium (POD) in elderly patients undergoing hip fracture surgery and to identify associated risk factors. METHODS: A retrospective study was conducted on 186 elderly patients who underwent hip fracture surgery at the Affiliated Hospital of Gansu University of Chinese Medicine from January 2021 to January 2023. Patients were categorized into GA and SA groups. The incidence of POD, postoperative pain control, and cognitive function changes were compared. Univariate and multivariate Logistic regression analyses were performed to identify independent risk factors for POD. The predictive value of significant factors was assessed using receiver operating characteristic (ROC) curve analysis. RESULTS: The incidence of POD was significantly higher in the GA group than that in the SA group (27.4% vs. 9.9%, P=0.002). The visual analogue scale scores at 24 hours postoperatively and analgesic drug usage were significantly higher in the GA group (both P<
0.002). Cognitive function scores postoperatively were significantly lower in the GA group (P<
0.005). Multivariate analysis identified longer operation time (P<
0.002, OR: 1.084, 95% CI: 1.047-1.123) and higher intraoperative blood loss (P=0.042, OR: 1.018, 95% CI: 1.002-1.035) as independent risk factors for POD. Conversely, higher preoperative hemoglobin (P=0.002, OR: 0.949, 95% CI: 0.919-0.981) and SA (P=0.021, OR: 0.174, 95% CI: 0.039-0.767) were protective factors. CONCLUSION: Compared to GA, SA significantly reduces POD incidence and improves postoperative analgesia in elderly hip fracture patients. Optimizing anesthetic strategies and preoperative assessments may enhance postoperative recovery in this population.