Experimental reduction in slow wave sleep vs reduction in slow wave sleep in aging.

An interesting study in Sleep, the Journal of Sleep and Sleep disorder Research compares the effects on daytime sleepiness of experimental awakenings from slow wave sleep in different age groups. Experimental reductions in slow wave sleep (SWS)lead to increases in daytime sleepiness (measured by MSLT) but normal age related declies in Slow Wave Sleep seen in health aging do not increase daytime sleepiness.

The article concludes that "age-related declines inSWS and reduction in daytime sleep propensity may reflect a lessening in homeostatic sleep requirement." "Healthy adults without sleep disorders can expect to be less sleepy during the daytime than young adults."

Older adults frequently complain of sllep disruptions, early morning wakening, wakening not refreshed, daytime sleepiness, and daytime napping. According to this study older adults with healthy sleep should not be subject to daytime tiredness so the question is are they tired due to poor sleep, sleep apnea or other health related disturbances. Daytime tiredness can be considered not a normal consequence of aging but a sign of loss of good sleep. The percentage of Slow Wave Sleep declines with age but should not cause problems of tiredness in otherwise healthy older adults.

Older adults with excessive daytime sleepiness, napping or other signs of excessive daytime sleepiness should be evaluated for sleep disorders and/or disturbed sleep. These symptoms should not be written off as normal consequences of aging. Better sleep will result in a better quality of life for older adults.