Prevalence and risk factors for postoperative delirium after hip fracture in the elderly: A systematic review and meta-analysis

BACKGROUND: The aim of this study was to systematically assess the prevalence and risk factors for hip fracture postoperative delirium (POD) in elderly patients. METHODS: PubMed, Embase, Cochrane Library, and other databases were searched to identify observational studies on risk factors for POD in patients with hip fracture, from database inception to April 1, 2025. Two independent reviewers conducted literature screening and data extraction, with disagreements resolved by discussion or consultation with a 3rd reviewer. The quality of the included studies was assessed using the Newcastle-Ottawa Scale. Meta-analysis was performed using Stata 15.0 software. Heterogeneity among studies was evaluated using the I² statistic and Cochran Q test. A random-effects model was applied when substantial heterogeneity was present (I² > 50% or P < .10), otherwise a fixed-effects model was used. In addition, subgroup analyses were conducted when appropriate to explore potential sources of heterogeneity. RESULTS: A total of 13 cohort studies (N = 18,850) were included, all the articles included in this study were of high quality. Meta-analysis results suggest that prevalence of POD after hip fracture was (effect size = 23%, 95% confidence intervals [CI] [19-28%]), age > 80 (odds ratios [OR] = 1.14, 95% CI [1.08-1.21]), ASA classification > 4 (OR = 4.19, 95% CI [1.85-9.52]); dementia (OR = 3.42, 95% CI [2.32-5.05]); diabetes (OR = 1.66, 95% CI [1.05-2.62]); general anesthesia (OR = 1.53, 95% CI [1.09-2.15]); hypertension (OR = 1.57, 95% CI [1.17-2.12]); male (OR = 1.23, 95% CI [1.12-1.35]); prior history of delirium (OR = 6.44, 95% CI [2.95-14.06]) were a risk factor for POD in elderly patients with hip fracture. CONCLUSION: In this study, we assessed the relationship between multiple factors and pod in elderly hip arthroplasty by meta-analysis, which showed that age >80 years, ASA score >4, dementia, diabetes mellitus, general anesthesia, hypertension, being male, and a history of delirium were all risk factors for POD. These findings highlight the importance of perioperative management in high-risk elderly patients.