MODULE SUPPLEMENT: NEUROLOGICAL SYSTEM
Sleep Changes with Aging

Researchers continue to learn about the purposes of sleep and its structure, as assessed using an EEG, and there has been some debate about the criteria used to evaluate the stages of sleep in older persons. However, most of the literature suggests that sleep changes do occur with age. Sleep is divided into Non Rapid Eye Movement (Non-REM) sleep, which is the more quiet sleep, and REM sleep, which is associated with dreaming and enhanced autonomic activity, but also with reduced or absent voluntary muscle tone (Haponik & McCall, 1999). Non-REM is divided in turn into four stages: Stage I, which is the transitional, light stage of sleep; Stage II, during which sleep spindles and k complexes appear on the EEG; Stage III, which is the first stage of deep sleep; and Stage IV, which is deep sleep and considered important to the restorative function attributed to sleep.

Older adults spend more time in Stage I Non-REM and less time in Stage IV. REM sleep tends to be decreased overall but more equally distributed across the night (Haponik & McCall, 1999). Older adults also tend to take longer to fall asleep, at least as subjectively reported.

However, of key importance is the assessment. It is essential that factors that disrupt sleep, such as medications, disease conditions, urinary problems, depression, or pain be reviewed and sleep disorders such as sleep apnea be ruled out. Treating a sleep compliant before delineating its underlying cause can lead to further morbidity or even mortality.