While the specific causes of<unk>  have not been empirically proven, some evidence suggests that circadian rhythm disruption increases<unk>  behaviors. In humans, sunset triggers a biochemical cascade that involves a reduction of dopamine levels and a shift towards melatonin production as the body prepares for sleep. In individuals with dementia, melatonin production may be decreased, which may interrupt other neurotransmitter systems. Other causes or precipitating factors that may lead to sundown syndrome may include hormonal changes, disturbances in REM sleep, individual and/or caregiver fatigue, inappropriate medication use, or being predisposed to behavioral disorders from chronic neurological diseases. Resources in an institution's environment can also play a role as a symptom trigger. A reduced number of staff in the evening can attribute to more unmet needs and a lower threshold for agitation for individuals with sundown syndrome.<unk>  should be distinguished from delirium, and could be presumed to be delirium when it appears as a new behavioral pattern until a causal link between sunset and behavioral disturbance is established. People with established<unk>  and no obvious medical illness may be suffering from impaired circadian regulation, or may be affected by nocturnal aspects of their institutional environment such as shift changes, increased noise, or reduced staffing (which leads to fewer opportunities for social interaction). Delirium is generally an acute event that can span over a time period of hours to days. Disturbances in circadian rhythms It is thought that with the development of plaques and tangles associated with Alzheimer's disease there might be a disruption within the suprachiasmatic nucleus (SCN). The SCN is located in the hypothalamus and is associated with regulating sleep patterns by maintaining circadian rhythms, which are strongly associated with external light and dark cues. A disruption within the suprachiasmatic nucleus would seem to be an area that could cause the types of confusion that are seen in<unk> . However, finding evidence for this is difficult, as an autopsy is needed to analyze this disruption properly. By the time a person experiencing Alzheimer's has died, they have usually surpassed the level of brain damage (and associated dementia) that would be associated with<unk> . This hypothesis is, however, supported by the effectiveness of melatonin, a natural hormone, to decrease behavioral symptoms associated with<unk> . The pineal gland produces melatonin when signaled by the SCN to help maintain circadian rhythms. Melatonin supplementation can be administered to older adults as their natural hormonal production decreases over time. Another cause can be oral problems, like tooth decay with pain. When the time a meal is served comes close, a person can show symptoms of<unk> . This cause is not widely recognized; however, anticipation of food can increase dopamine levels, and dopamine and melatonin have an antagonistic relationship. Serotonin has also been observed to potentially have a key role in the regulation of circadian rhythm as research has shown that serotonergic agonism in the SCN results in "phase shifts" in portions of the light-dark cycle. In addition to the effects on circadian rhythm, serotonin is also known to be involved in the regulation of aggression. Due to the serotonergic signaling deficiencies of Alzheimer's disease, it has been commonly reported that deficiencies in serotonin have been associated with worsening circadian rhythm or aggression. Risk Factors Elderly people often experience multiple comorbidities that may contribute to the phenomenon of<unk>  syndrome through neurodegeneration. * Neurological disorders: Alzheimer's disease, Parkinson's disease, Huntington's disease, Lewy body dementia, fronto-temporal dementia, subcortical dementia. * Neurobehavioral disorders: anxiety and depression. * Cerebrovascular disease risk factors: hypertension, smoking, obesity. *Genetic predisposition: presence of the ApoE4 allele has associations with sundown syndrome in peoples experiencing Alzheimer's disease.
Sundowning
Food craving
Sleepwalking
Fear of trains
Snatiation
Fidgeting
Insomnia
Sleep-talking