Delirium in hip fracture patients admitted from home during the COVID-19 pandemic is associated with higher mortality, longer total length of stay, need for post- acute inpatient rehabilitation, and readmission to acute services

Delirium is associated with adverse outcomes following hip fracture, but the prevalence and sig-nificance of delirium for the prognosis and ongoing rehabilitation needs of patients admitted from home is less well studied. Here, we analyzed relationships between delirium in patients ad-mitted from home with 1) mortality; 2) total length of hospital stay; 3) need for post-acute inpa-tient rehabilitation; and 4) hospital readmission within 180 days. Methods This observational study used routine clinical data in a consecutive sample of hip fracture patients aged & GE; 50 years admitted to a single large trauma centre during the COVID-19 pandemic between 1 March 2020 and 30 November 2021. Delirium was prospectively assessed as part of routine care by the 4 A's Test (4AT), with most assessments performed in the emergency department. Associ-ations were determined using logistic regression adjusted for age, sex, Scottish Index of Multiple Deprivation quintile, COVID-19 infection within 30 days, and American Society of Anesthesiolo-gists grade. Results A total of 1,821 patients were admitted, with 1,383 (mean age 79.5 years; 72.1% female) directly from home. Overall, 87 patients (4.8%) were excluded due to missing 4AT scores. Delirium preva-lence in the whole cohort was 26.5% (460/1,734): 14.1% (189/1,340) in the subgroup of patients admitted from home, and 68.8% (271/394) in the remaining patients (comprising care home residents and inpatients when fracture occurred). In patients admitted from home, delirium was associated with a 20-day longer total length of stay (p < 0.001). In multivariable analyses, delirium was associated with higher mortality at 180 days (odds ratio (OR) 1.69 (95% confidence interval (CI) 1.13 to 2.54); p = 0.013), requirement for post-acute inpatient rehabilitation (OR 2.80 (95% CI 1.97 to 3.96); p < 0.001), and readmission to hospital within 180 days (OR 1.79 (95% CI 1.02 to 3.15); p = 0.041). Conclusion Delirium affects one in seven patients with a hip fracture admitted directly from home, and is asso-ciated with adverse outcomes in these patients. Delirium assessment and effective management should be a mandatory part of standard hip fracture care.