Sundowning and circadian rhythm disorders in dementia

Acta Neurol Belg. 2006 Dec;106(4):168-75.

Abstract

Sleep disorders and disruptive nocturnal behaviours are commonly reported in people with senile dementia and present both a significant clinical problem and a cause of increased stress for caregivers. Neuronal degeneration of cholinergic Nucleus basalis Meynert (NBM) neurons promote rest-activity disturbance and Sundowning in Alzheimer's disease. NBM neurons modulate the activity of the mainly cholinergic suprachiasmatic nucleus (SCN) and the induction of NONREM sleep. Sundowning might be explained as a syndrome occurring when arousal is to be processed while the neocortex is already turned "off" to (NONREM) sleep. The therapeutic measures should thus primarily be aimed at the stimulation of the circadian system and enforcing "external Zeitgebers". Pharmacologically, application of cholinergic enhancers i.e. cholinesterase inhibitors and melatonin supports and should stabilize the weakened structures.

Publication types

  • Review

MeSH terms

  • Aged
  • Basal Nucleus of Meynert / metabolism
  • Basal Nucleus of Meynert / physiopathology
  • Cerebral Cortex / metabolism
  • Cerebral Cortex / physiopathology
  • Cholinergic Fibers / metabolism
  • Cholinesterase Inhibitors / therapeutic use
  • Chronobiology Disorders / etiology*
  • Chronobiology Disorders / physiopathology*
  • Chronobiology Disorders / therapy
  • Darkness / adverse effects
  • Dementia / complications*
  • Dementia / physiopathology*
  • Dementia / therapy
  • Humans
  • Phototherapy / standards
  • Sleep / drug effects
  • Sleep / physiology
  • Sleep Wake Disorders / etiology*
  • Sleep Wake Disorders / physiopathology*
  • Sleep Wake Disorders / therapy

Substances

  • Cholinesterase Inhibitors