Circadian and sleep disturbances in the elderly

Exp Gerontol. 2000 Dec;35(9-10):1229-37. doi: 10.1016/s0531-5565(00)00191-1.


The incidence of disturbed sleep is strongly increased in healthy and demented elderly. Age-related alterations in the circadian timing system appear to contribute strongly to these problems. With increasing age, a lack of input to the suprachiasmatic nucleus (SCN), the biological clock of the brain, may accelerate de-activation of neurons involved in the generation of 24-h rhythm or output of this rhythm. This process appears to be reversible, since supplementation of stimuli that impinge on the SCN can re-activate these neurons and ameliorate disturbances in the sleep-wake rhythm.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aging / physiology*
  • Circadian Rhythm / physiology*
  • Humans
  • Melatonin / therapeutic use
  • Photoperiod
  • Sleep / physiology
  • Sleep Wake Disorders / etiology
  • Sleep Wake Disorders / physiopathology*
  • Sleep Wake Disorders / therapy
  • Suprachiasmatic Nucleus / physiopathology


  • Melatonin