Delirium as a marker of undiagnosed dementia in the general hospital: Evaluation of pragmatic methods of screening and follow-up

Delirium is an acute neuropsychiatric syndrome commonly affecting older people in general hospital. Dementia is common in older people in hospital with a distinct phenotype. Delirium and dementia commonly co-exist and are associated with adverse outcomes. The aims of the thesis were to developed pragmatic methods to screen for dementia in patients with delirium and to examine the outcomes of people with delirium. A prospective cohort study of older people admitted to hospital with delirium was carried out. Cognitive impairment was common among older people with delirium, with 3 in five having dementia and 1 in 5 having unrecognized dementia. Previously published dementia screening tools are scarce and not valid in people with delirium. Informant tools (the IQCODE and AD8) are highly sensitive and specific to detect dementia and combined cognitive impairment (MCI or dementia) in delirium. Delirium duration, severity, the hypoactive subtype and dysregulated inflammation were predictors of adverse outcomes in older people with delirium. \nThis thesis confirms the close relationship between delirium and dementia in general hospitals. It offers pragmatic solutions to both screening for dementia in older people with delirium, and improving follow-up by detailing predictions of adverse outcome. \n