Psychiatry Investig.  2011 Dec;8(4):275-287.

Sundown Syndrome in Persons with Dementia: An Update

• Khachiyants N
• Trinkle D
• Son SJ
• Kim KY

Abstract

"Sundowning" in demented individuals, as distinct clinical phenomena, is still open to debate in terms of clear definition, etiology, operationalized parameters, validity of clinical construct, and interventions. In general, sundown syndrome is characterized by the emergence or increment of neuropsychiatric symptoms such as agitation, confusion, anxiety, and aggressiveness in late afternoon, in the evening, or at night. Sundowning is highly prevalent among individuals with dementia. It is thought to be associated with impaired circadian rhythmicity, environmental and social factors, and impaired cognition. Neurophysiologically, it appears to be mediated by degeneration of the suprachiasmatic nucleus of the hypothalamus and decreased production of melatonin. A variety of treatment options have been found to be helpful to ameliorate the neuropsychiatric symptoms associated with this phenomenon: bright light therapy, melatonin, acetylcholinesterase inhibitors, N-methyl-d-aspartate receptor antagonists, antipsychotics, and behavioral modifications. To decrease the morbidity from this specific condition, improve patient's well being, lessen caregiver burden, and delay institutionalization, further attention needs to be given to development of clinically operational definition of sundown syndrome and investigations on etiology, risk factors, and effective treatment options.

Keyword

Sundowning; Alzheimer's disease; Dementia

MeSH Terms

Alzheimer Disease
Antipsychotic Agents
Anxiety
Caregivers
Cholinesterase Inhibitors
Circadian Rhythm
Cognition
Dementia
Dihydroergotamine
Humans
Hypothalamus
Institutionalization
Melatonin
N-Methylaspartate
Phototherapy
Risk Factors
Suprachiasmatic Nucleus
Antipsychotic Agents
Cholinesterase Inhibitors
Dihydroergotamine
Melatonin
N-Methylaspartate