The intersection of delirium and long-term cognition in older adults: the critical role of delirium prevention

Abstract

Delirium, a neuropsychiatric syndrome characterized by an acute and usually reversible state of confusion, while dementia is a chronic, acquired cognitive impairment that significantly reduces a patient's ability to perform daily tasks, learn, work, and engage in social interactions. Previous studies indicates that individuals with dementia are more susceptible to delirium than the general population, and that delirium serves as an independent risk factor for the subsequent onset of dementia. However, a major controversy in this field concerns whether delirium is merely a marker of vulnerability to dementia, or whether delirium-induced adverse outcomes such as falls and functional decline contribute to dementia, or whether delirium directly causes permanent neuronal damage and lead to dementia. It is possible that all these hypotheses hold some truth. In this review, we examine the shared and distinct mechanisms of delirium and dementia by reviewing their clinical features, epidemiology, clinicopathological, biomarkers, neuroimaging, and recent experimental studies, and we discuss the importance of targeting delirium to explore new preventive and therapeutic strategies for reducing long-term cognitive impairment.

Keywords: Alzheimer's disease; Biomarker; Delirium; Dementia; Prevention.