150Delirium is Highly Prevalent, Inadequately Screened for, Underdiagnosed, and Associated with Significant Mortality in a Large Urban Hospital

Abstract

Background: Delirium is a prevalent and under-recognised condition, most commonly affecting older adults. Delirium is associated with increased length of stay, falls, institutionalisation, novel dementia, high costs, and increased mortality. No point prevalence study to date has been carried out in the British Isles. Methods: Data were collected for all non-elective admissions, aged ≥65, to all specialties, within a 48 hour period prior to World Delirium Day. Exclusion criteria included intensive care admissions, those not yet seen by an admissions team, undue distress, and patients at the end of life. Primary outcome was the point prevalence of delirium. Secondary outcomes included proportion screened for delirium on admission, record of delirium diagnosis in medical notes and discharge documentation, length of stay, and mortality. Results: 157 patients were identified. 33 were included for analysis after exclusions. Mean age was 80.3 years (range 65-96). 54.5% were male. 21% had existing dementia. 36% had delirium screening carried out. Mean length of stay was 8.6 days. 11 patients (33%) were found to have delirium. Mean age was 84.4 years (range 71-96). 36% had existing dementia. 45% had a documented diagnosis of delirium in their medical notes. 36% of patients died as inpatients. 27% had delirium on their discharge letter. Mean length of stay was 13 days. Conclusion: We report a 33% point prevalence in emergency admissions ≥65 years. Our findings shows that delirium is under-screened, underdiagnosed and poorly documented. Delirium was associated with increasing age, higher clinical frailty score, and pre-existing dementia. Notably, patients with delirium had a significantly higher mortality rate (36% vs 0%). They also had longer length of stay. This point prevalence study can be used to justify better resource allocation for patients with delirium going forward. With its known impact, it is imperative that we improve clinician understanding of screening, diagnosis and management of delirium.