Sundowning in Dementia: Clinical Relevance, Pathophysiological Determinants, and Therapeutic Approaches

Abstract

Sundowning means the emergence or worsening of neuropsychiatric symptoms (NPS) in the late afternoon or early evening. This syndrome has been recognized since a long time in the field of dementing illnesses and is well known among most of health-care providers involved in the assistance of people with dementia. Indeed, it represents a common manifestation among persons with dementia and is associated with several adverse outcomes (such as institutionalization, faster cognitive worsening, and greater caregiver burden). Its occurrence and phenotypic characteristics may be influenced by diverse neurobiological, psychosocial, and environmental determinants. Moreover, it may pose diagnostic challenges in relation to other common causes of behavioral disruptions. Beside these considerations, this phenomenon has so far drawn limited clinical and scientific interest compared to other specific NPS occurring in dementias, as indicated by the lack of commonly agreed definitions, specific screening/assessment tools, and robust estimates on its prevalence. Accordingly, no randomized controlled trial specifically investigating the effectiveness of pharmacological and non-pharmacological strategies in managing this condition among demented patients has been yet conducted. In the present narrative review, we present and discuss available evidence concerning sundowning occurring in people with dementia. A special focus is given to its definitions, pathophysiological determinants, and clinical relevance, as well as to the clinical and therapeutic approaches required for its management in the daily practice.

Recent advances in the study of aggression

“…In many psychiatric patients, violent behaviors intensify during certain times of day, indicating that circadian circuits controlling arousal may be important modulators of VMH neurons driving aggression [28]. Though this effect has been well documented in clinical populations, only one recent study has investigated the relevant circuit mechanisms in an animal model of aggression [29].…”

Real-World Effectiveness of Ramelteon and Suvorexant for Delirium Prevention in 948 Patients With Delirium Risk Factors

“…33 In contrast to delirium, however, no standardized diagnostic criteria have been formulated for sundowning because of the lack of consensus surrounding its definition. 34 Therefore, delirium is well established and appears in the DSM-5, whereas sundowning remains undefined and a subject of controversy, mainly because of its limited evaluation in homes and nursing homes. This ambiguity surrounding sundowning could be explained by the existence of some type of short-lasting delirium in the evening that overlaps sundowning or by the fact that some types of sundowning may be considered a subtype of delirium.…”

Screening for Vision Impairments in Individuals with Dementia Living in Long-Term Care: A Scoping Review

“…It is possible that untreated visual impairments in individuals with dementia could 1) evoke or exacerbate symptoms such as depression, anxiety, loneliness, or aggression [22]; 2) contribute to impaired performance on tasks requiring cognitive executive functioning or memory due to increased cognitive load [23]; and/or 3) result in accelerated rates of cognitive decline [13]. Individuals with dementia may also respond to vision loss differently than those without (e.g., be more prone to visual hallucinations [19,24] or time-of-day effects [25]). There is encouraging evidence to suggest that treating visual impairments can improve the quality of life of individuals with mild or moderate cognitive impairments [19,[26][27][28], but the effects of interventions on individuals with dementia have not been well investigated.…”