Sundown syndrome and dementia

The terms “sundown syndrome” or “sundowning” are used to describe a wide range of neuropsychiatric symptoms often occurring in individuals with dementia. It is a poorly defined entity. The goal of this review is to describe the phenomenon of this syndrome, its clinical characteristics and management. Medline and Google Scholar searches were conducted for relevant articles, chapters, and books published before 2014. Search terms used included behavioural and psychological symptoms of dementia (BPSD), circadian rhythms, dementia, sundowning, sundown syndrome. Publications found through this indexed search were reviewed for further relevant references. Sundowning is a complex behavioural disorder with tremendous costs for families, caretakers, and patients themselves. Increased understanding of the sundowning syndrome may lead to more effective environmental, behavioural, or pharmacological interventions.