Older adults normally have decreasing amount of time spent in REM sleep, less total time sleeping and more frequent nocturnal awakenings, as well as early-morning awakening.
A hypnogram is a chart showing depth of sleep on the y-axis (awake at the top and Stage 3 deep sleep at the bottom) and total hours slept on the x-axis. Older adults exhibit more frequent spikes of wakefulness throughout the night on a hypnogram as well as fewer periods of deep sleep.
Neubauer notes that the elderly are more likely to have sleep difficulties such as those mentioned above. These may be exacerbated by irregular sleep-wake cycles and daytime napping, as well as prescription medications, caffeine, and alcohol. Due to increased side effects of medications such as histamines (side effects of drowsiness, urinary retention in particular in the elderly), he recommends a behavioral approach first to promote sleep hygiene and treat insomnia.
Cohen-Mansfield et al. found that in a 20-year prospective cohort study of older Israeli adults aged 75-94, nighttime sleep duration of greater than 9 hours was related to increased mortality compared to 7-9 hours' sleep (HR 1.31 p<0.01). Fewer than 7 hours' sleep was not associated with any change in mortality risk.
Illustration A compares histograms between children, young adults, and the elderly.
Answer 1-4: These would be expected to have greater REM sleep and fewer nocturnal awakenings compared to the older adult.
Neubauer DN. Sleep problems in the elderly. Am Fam Physician. 1999 May 1;59(9):2551-8, 2559-60. Review. PubMed PMID: 1032336
PMID:1032336 (Link to Abstract)
Cohen-Mansfield J, Perach R. Sleep duration, nap habits, and mortality in older persons. Sleep. 2012 Jul 1;35(7):1003-9. doi: 10.5665/sleep.1970. PubMed PMID: 22754047; PubMed Central PMCID: PMC336921
PMID:22754047 (Link to Abstract)