Association of pre- and postoperative delirium with functional status at discharge after hip fracture: findings from the Gruppo Italiano di Ortogeriatria (GIOG 2.0) study

Purpose Evidence on how the timing of delirium onset influences functional outcomes after hip fracture is scarce, yet is crucial for informing service planning and optimizing orthogeriatric care pathways. We therefore examined the association between delirium occurring at distinct perioperative phases and functional status at discharge in older patients undergoing hip fracture surgery. Methods This multicenter prospective cohort study included patients aged >= 65 years who underwent hip fracture surgery between July 2019 and June 2024 at 12 Italian orthogeriatric centers. Delirium was assessed with the 4AT from the day before surgery through postoperative day three. Poor functional status at discharge was defined as a Cumulated Ambulation Score <= 2. Associations of preoperative, postoperative, and preoperative + postoperative delirium with poor functional status were examined using multivariable logistic regression adjusted for age, sex, comorbidity, pre-fracture activities of daily living, pre-fracture ambulation, and time-to-surgery > 48 h. Results A total of 1492 patients were included (median age 84 years, Q1-Q3: 79-89; 76.9% female). Delirium occurred in 444 (29.8%) patients: 34 (2.3%) had preoperative delirium, 182 (12.2%) postoperative delirium, and 228 (15.3%) both. The combined presence of preoperative and postoperative delirium was significantly associated with higher odds of poor functional status at discharge (Odds Ratio: 1.57; 95% Confidence Interval: 1.13-2.20) versus no delirium. Conclusion Delirium persisting from the preoperative to the postoperative phase was associated with poor functional status at discharge. Systematic assessment of delirium in both phases may help identify older hip fracture patients at increased risk of poor functional outcome.