Frequency, risk factors, and prognosis of prolonged delirium in elderly patients after hip fracture surgery

Abstract

Background Delirium in elderly patients after hip fracture surgery is believed to be a transient event, although it frequently lasts for more than 4 weeks. Questions/purposes We determined the incidence, risk factors, morbidity, and mortality of prolonged delirium in elderly patients after hip fracture surgery. Patients and Methods We evaluated 232 elderly patients (older than 65 years) (232 hips) who underwent hip fracture surgery for the development and duration of delirium and categorized them into three groups; nondelirium group, transient (≤ 4 weeks) delirium group, and prolonged (>4 weeks) delirium group. Patients underwent a global geriatric evaluation, which included postoperative complications, mortality, and functional and mental status evaluations. The three groups were compared with respect to these variables. Results Seventy patients (30.2%) had delirium develop, and among these, 14 (20%) had prolonged delirium with a total incidence of 6%. Multivariate analysis showed preinjury dementia was a risk factor of prolonged delirium. At the final followup, five (62.5%) of the eight patients who were ambulatory outdoors in the prolonged delirium group became housebound, whereas only 18 (16.4%) of the 110 patients who were ambulatory outdoors in the nondelirium group became housebound. Survival at 40 months was 81.0% (95% confidence interval, 72.6%-89.3%) in the nondelirium group and 63.6% (95% confidence interval, 35.2%-92.1%) in the prolonged delirium group. Conclusions Prolonged delirium was found to be associated with a poor functional outcome and increased mortality. Level of Evidence Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence. © 2011 The Association of Bone and Joint Surgeons.