Sleep and Aging-Part I
(3/18/99)- An article in The Journal of the American Medical Association discussed the merits of cognitive behavior therapy in dealing with insomnia in older adults Dr. Charles Morin, professor of psychology at Laval University in Quebec concludes that in combination with sleeping medication effective treatment can ensue.
Sleep is an activity that human beings engage in for about one-third of their lives. Recent data suggests that 70 million Americans may suffer from either chronic sleep disorder or intermittent sleep deprivation.
Sleep is an active state with many different components in a neurological sense. There are many ways in which sleep is disordered either by disease or dysfunction of the nervous system and/or of the mind.
Sleep is divided into 2 distinct states: D-sleep (desynchronized EEG pattern sleep) and S-sleep (synchronizes EEG pattern sleep). D-sleep is also known as REM or dream sleep; S-sleep as NREM, orthodox or quiet sleep. S-sleep is divided into stages 1, 2, 3, and 4, with stage 1 being the lightest and stage 4 the deepest. NREM sleep lasts from 60 to 100 minutes followed by 10-40 minutes of REM sleep and the cycle is continuous throughout the night. Typically about 80 percent of adults sleep time is spent in NREM sleep and 20 percent in REM sleep. REM sleep tends to increase during the second half of the night. The amount of REM sleep appears to determine the amount of rest. When REM sleep is interrupted, tiredness tends to develop.
Sleep begins with the transition from wakefulness into light, stage 1 NREM sleep. During this stage, the arousal threshold is low. Stage 2, NREM sleep, follows and after a time, usually less than an hour after sleep onset, sleep stages 3 and 4 of NREM sleep (also known as delta or slow wave sleep) are entered.
A newborn spends about 50% of sleep time in REM sleep. Day sleep begins to be replaced by longer periods of lighter sleep after age thirty. Sleep in advanced age is characterized by reduced amounts of slow wave sleep, increased wakefulness after sleep onset, more frequent awakenings and a decrease in EEG delta wave activity.
It is not the need for sleep but the ability to sleep that diminishes with age. Older adults are objectively sleepier in the daytime, indicating they are not getting enough sleep at night. Their sleep is disrupted by circadian rhythm (biological clock) changes, disorders such as sleep disordered breathing (apnea) and periodic limb movement in sleep, medical illness, psychiatric illness, medication use and poor sleep habits.
Researchers report that older people have less stage-three and stage-four sleep (i.e. deep sleep) and less rapid eye movement sleep (dream sleep). Their sleep efficiency ( the amount of time asleep given the amount of time in bed) is reduced and the number of naps taken during the day increases. Older people are sleepy during the day (i.e. have shortened sleep onset latency) suggesting that it is the not the NEED for sleep but the ABILITY to sleep that is reduced.
Laboratory analysis of human sleep rhythms has documented a temporal shift of bedtime and awakening time to earlier hours. This effect has been attributed to shortening of the free-running period of the circadian clock, and the subsequent alteration of the phase of enhancement to the light-dark cycle. The sleep of the elderly, even in a healthy population, has been shown to be altered in total amount, relative quality and temporal organization. Marked reductions in the amount of stage 3 and 4 sleep along with increases in the number and duration of awakenings at night have been documented polysomnographically. It has been proposed that the earlier rise in body temperature accompanying the phase advances in the elderly contributes to the fragmentation of sleep episodes. It is this fragmentation that contributes to an impairment of alertness and increased daytime sleep propensity.
The sleep/wake cycle is controlled by our biological clock. The average younger adult gets sleepy at around 10 or 11 PM and sleeps for 8 to 9 hours, waking between 6 to 8 AM. As we age, our circadian clock advances, causing advanced sleep phase syndrome. People with this syndrome get sleepy early in the evening (around 8 or 9 PM). If they were to go to bed at that time, they would sleep for about 8 hours and wake up 4 to 5 AM. However, when they try to stay up to 10-11 PM, their bodies still wake up at 4 to 5 AM. This means they only get 5-6 hours of sleep, the amount of time they were in bed before their advanced sleep /wake cycle wakes them up.
Pharmacotherapy is the most common method for treating insomnia. Bezodiazepine hypnotics are the most commonly prescribed hypnotics. Their sleep-inducing properties on a short-term basis have been shown in controlled studies, but there are few data on their long-term efficacy in management of chronic insomniac patients. Furthermore, the development of tolerance and dependence under long-term administration, as well as the occurrence of rebound insomnia upon discontinuation of benzodiazepine hypnotics, have restricted their use in treatment of chronic insomnia.
Alternative treatment such as sedating antidepressants may be restricted to the treatment of chronic insomnia patients with drug alcohol dependence in their clinical history.
Recently, much has been written about the role of Melatonin in assisting sleep especially related to jet lag sleep difficulties. Attenbaum et al in a study of healthy middle aged persons (47-67 years) indicated that low dose Melatonin improves sleep.
Melatonin is secreted by the pineal gland at night and is associated with sleep disorders in old age due to decrease in humoral production in the pineal gland as we age. Slow release preparations (2 mg) of melatonin are able to increase plasma melatonin for 5-7 hours, which acts on prolactin within the brain and influences the sleep biological clock. Thus melatonin may play an indirect role in the regulation of nocturnal prolactin secretion. It should be noted that stress could induce melatonin secretion. The New England Journal of Medicine in its Jan. 16, 1997 issue has a review article on Melatonin in Humans by Amnon Brzezinski, MD. He states "There is now evidence that melatonin may have a role in the biological regulation of circadian rhythms, sleep, mood and perhaps reproduction, tumor growth and aging" (p. 186)
Psychological factors have mediating role in insomnia. This has stimulated the development of nonpharmacological treatments, particularly cognitive-behavioral interventions. These treatment methods are typically aimed at modifying maladaptive sleep practices.
The three most common nonpharmaceutical treatment interventions: are relaxation therapies aimed at reducing somatic and cognitive arousal; sleep hygiene education which deals with inappropriate sleep goals, habits, napping and unrealistic expectations about the quality and duration of sleep, especially in later life; and stimulus control therapy which looks at the "stimulus" properties of the bedroom and cues for wakefulness.
Trying to incorporate all three methods into a program that is not costly, takes a minimum of effort and has a high chance of succeeding. This leads us to suggest the following "rehabilitation strategy" for sleep problems in the elderly:
If you have difficulty falling asleep, try the following for at least one-month:
Be advised that these techniques should be tried a minimum of two weeks to a month before discarding them as not applicable to your situation. It is also important that you determine whether any medical condition or possibly prescription medications are keeping you awake. This means checking with your physician, informing him/her of all medications, over-the-counter drugs, vitamins and herbal preparations you are taking. All these can have an effect on sleep patterns.
In Dr. Morin's study referred to at the beginning of this article 78 men and women, aged 55 and above were used in the trial group. All had difficulty in falling asleep or staying asleep, at least 3 nights a week for at least 6 months, and had complained of daytime fatigue, impaired functioning or mood disturbances that they attributed to loss of sleep. Subjects who received weekly 90 minute sessions of cognitive-behavioral therapy, a trial of the sleeping pill Restoril, or a combination of the therapy and Restoril all showed significant improvement in their sleep patterns at the end of the 8 week treatment period. The subjects in Dr. Morin's study were instructed in basic principles of "sleep hygiene" including the effects of caffeine, alcohol, and diet, and taught ways to increase their chances of sleeping as described in some of the 9 items above.
In summary, be aware that as we get older our sleep patterns change. A newborn spends about 50% of sleep time in REM sleep. Typically, about 80% of an adults sleep time is spent in NREM sleep. Deep sleep begins to be replaced by longer periods of lighter sleep after age thirty. Adults tend to wake up during the night more. This is neither good nor bad. It is normal. Before you assume that you are not getting enough sleep, keep a 24-hour sleep log for a week. Record when you go to bed, how long you sleep, how often you remember waking, how long it takes you to fall asleep again and when and how long you take naps during the day. Keep a record of how you felt during the day. Follow the rules stated above.
Monitoring what you eat during the day is also important. At night, it is important to have foods rich in starches and relatively low in proteins.
Most important of all, DO NOT BROOD ABOUT WHAT SEEMS TO BE INSOMNIA. This will keep you awake all by itself.
REMEMBER NO ONE EVER DIED OF INSOMNIA.
Sleeping pills are not always the answer. For some people, they have the reverse effect. They keep the person awake.
See also: Sleep and Aging: Disturbed Sleep-Part II
FOR AN INFORMATIVE AND PERSONAL ARTICLE ON PRACTICAL SUGGESTIONS WHEN SELECTING A NURSING HOME SEE OUR ARTICLE "Selecting a Nursing Home"
By Harold Rubin, BA, ABD, CRC, Guest Lecturer
updated March 18, 1999