Dementia in the acute hospital: the prevalence and clinical outcomes of acutely unwell patients with dementia

Background: Studies have demonstrated that a significant minority of older persons presenting to acute hospital services are cognitively impaired; however, the impact of dementia on long-term outcomes is less clear. Aim: To evaluate the prevalence of dementia, both formally diagnosed and hitherto unrecognised in a cohort of acutely unwell older adults, as well as its impact on both immediate outcomes (length of stay and in-hospital mortality) and 12-month outcomes including readmission, institutionalisation and death. Design: Prospective observational study. Methods: 190 patients aged 70 years and over, presenting to acute hospital services underwent a detailed health assessment including cognitive assessment (standardised Mini Mental State Examination, AD8 and Confusion Assessment Method for the Intensive Care Unit). Patients or informants were contacted directly 12 months later to compile 1-year outcome data. Dementia was defined as a score of 2 or more on the AD8 screening test. Results: Dementia was present in over one-third of patients (73/190). Of these patients, 36% (26/73) had a prior documented diagnosis of dementia with the remaining undiagnosed before presentation. The composite outcome of death or readmission to hospital within the following 12 months was more likely to occur in patients with dementia (73% (53/73) vs. 58% (68/117), P = 0.043). This finding persisted after controlling for age, gender, frailty status and medical comorbidities, including stroke and heart disease. Conclusion: A diagnosis of dementia confers an increased risk of either death or further admission within the following 12 months, highlighting the need for better cognitive screening in the acute setting, as well as targeted intervention such as comprehensive geriatric assessment.