Sleep and Sleep Disorders

Introduction
The prevalence of sleep complaints increases dramatically with age and is estimated to be about 40% in the elderly population. These complaints include difficulty falling asleep, waking up at night, waking up too early in the morning, not feeling well rested, and needing to nap during the day. In an epidemiologic study of more than 9000 participants aged 65 and over, more than half reported at least one sleep complaint occurring most of the time. Women were more likely to report nighttime complaints but were less likely to nap during the day compared to men.

The most common complaint was waking up at night (30%), followed by daytime naps (25%) and difficulty falling asleep (19%). Less than 20% reported rarely or never having any sleep complaint. Sleep complaints were associated with coexisting health disorders, including poor self-perceived health, depressive symptoms, respiratory symptoms, physical disabilities, chronic medical conditions, and medication use. However, of the healthy minority in this study, over one-fourth reported at least one chronic sleep complaint.

Although age-related changes do occur in normal sleep, sleep problems in the elderly are not a consequence of the aging process per se but are strongly related to medical and psychiatric comorbidity as well as psychosocial changes in later life. Furthermore, some specific sleep disorders such as sleep disordered breathing, periodic limb movements in sleep, and REM sleep behavior disorder are more prevalent with age, although not exclusive to this age group.