Sleep in the Elderly: Unanswered Questions.

Sleep normally changes with aging, with implications for healthy elderly individuals as well as for those with disease states. Less slow wave sleep (deep sleep) is expected, along with more awakenings, and a tendency toward earlier sleep times. Rapid eye movement sleep behavior disorder is seen primarily in elderly individuals, and it often represents the earliest sign of a chronic and progressive neurologic disease. Complaints of difficulty initiating and maintaining sleep (insomnia) become more common with aging. Irregular breathing with sleep also becomes more common, with an increased Apnea Hypopnea Index that may not always be clinically important.