Before examining how sleep changes with age, it's necessary to understand the basic sleep stages. Normal sleep consists of two major states: REM (Rapid Eye Movement) sleep and NREM (nonREM) sleep. NREM sleep is divided further into four sleep stages, numbered stage 1, 2, 3 and 4. Sleep typically begins with stage 1 before progressing into the later stages. Sleep deepens with each stage achieved; stages 3 and 4 (also called delta sleep) provide our bodies' deepest sleep. Our fifth stage is REM sleep, where dreaming occurs.
What Do Sleep Stages Have to Do with Sleeping Well?
In general, changes in one's sleep architecture or stages affect how deep sleep is. Middle-aged and elderly people tend to spend less time in deeper sleep than younger people. By age 60 or 70, many adults experience a decrease in the proportion of time spent in delta sleep. This is particularly true for elderly men. However, the percentage of REM sleep remains relatively stable.
In late adulthood, the first REM sleep periods come faster than in earlier years. Are the kinds of dreams experienced different? Some research suggests that older men tend to have more passive, inner-directed dreams, while older women tend to dream more active, outgoing dreams.
Are You Sleeping More, But Enjoying It Less?
Interestingly, the average total sleep time increases slightly after age 65. But so do reports of difficulty falling asleep. One study found that after 65, 13 percent of men and 36 percent of women reported taking more than 30 minutes to fall asleep.
What causes this difficulty? Research suggests that physiological and lifestyle changes are at fault. The elderly generally secrete lesser amounts of certain chemicals that regulate the sleep/wake cycle. Both melatonin (a substance produced by the pineal gland that promotes sleep) and growth hormone production decrease with age. There are also changes in the body temperature cycle which occur with age. These factors may cause, or be a consequence of, sleep problems. In addition, a decrease in exposure to natural light and a change in diet may exacerbate sleep difficulties. Some researchers theorize that daytime inactivity (lack of exercise) and decreased mental stimulation may also lead to the "aging" of sleep.
Falling asleep isn't the only difficulty older people may face at night. Sleep also becomes more shallow, fragmented and variable in duration with age. The elderly wake more frequently than younger adults. Recent research suggests that the aging bladder can contribute to a substantial degree of sleep disturbance in the elderly. A tendency to feel sleepier during the day than when younger results from these increased nocturnal awakenings.
It's important to remember that many healthy elderly individuals have no or few sleep problems.
Persistent Trouble Falling Asleep at Night or Frequent Drowsing by Day is Not Normal or Inevitable with Age.
Sometimes, age-related changes mask underlying sleep disorders. For example, sleep apnea, a breathing disorder, is more common in the middle and elder years. The repeated awakenings caused by a literal lack of breath lead to daytime sleepiness.
How do you tell whether daytime drowsiness is a result of a sleep disorder, sleep deficit or depression? By consulting a sleep specialist, who is skilled in diagnosing the problem and treating both symptom and cause.
Many older people consider poor sleep not worth complaining about and as inevitable and constant as death and taxes.
Actually, there are many things you can do about poor sleep, and there are many reasons to do something about sleep!
