Changes in circadian rhythms and sleep quality with aging: mechanisms and interventions

Neurosci Biobehav Rev. 1995 Winter;19(4):553-71. doi: 10.1016/0149-7634(95)00018-6.


Literature is reviewed indicating that aging is characterized by changes in circadian rhythms and sleep quality. The most marked change is an attenuation of amplitude. An advance of phase, a shortening of period, and a desynchronization of rhythms are also evident. The mechanisms underlying these changes are unknown. However, age-related changes in the retina, suprachiasmatic nucleus, and pineal gland seem relevant along with behavioral changes such as a reduction in physical activity and exposure to photic stimulation. Changes in circadian rhythms are frequently associated with a reduction in nighttime sleep quality, a decrease in daytime alertness, and an attenuation in cognitive performance; reversing such changes could enhance the quality of life for a large and rapidly increasing percentage of the population. Reversal appears possible by increasing melatonin levels with either appropriately timed exposure to photic stimulation and/or appropriately timed administration of exogenous melatonin. These interventions may increase aspects of genetic expression that have changed with aging. A hypothesis concerning the potential benefits of enhanced circadian amplitude is also offered.

Publication types

  • Review

MeSH terms

  • Aging / physiology*
  • Aging / psychology
  • Animals
  • Circadian Rhythm / physiology*
  • Humans
  • Sleep / physiology*
  • Sleep Wake Disorders / physiopathology
  • Sleep Wake Disorders / therapy