Uninterrupted, restorative sleep contributes to our well-being and optimal functioning. Sleep patterns change over the life span. We have learned to identify many conditions that disrupt healthy sleep patterns and to diagnose sleep disorders (1,2,3). Sleep research started in the 1960s and has escalated by leaps and bounds during the past ten years (1). We have learned to recognize normal sleep architecture and its changes in late life (4). The science of chronobiology has evolved and has helped us understand age-related changes in circadian sleep-wake rhythm regulation (5).
This column focuses on the commonly experienced loss of sleep in late life and the effects that this loss can have on quality of life and daytime functioning. I briefly describe the most common sleep disorders and psychiatric and other medical conditions that can contribute to sleep loss in late life. I review the benefits of selected nonpharmacologic interventions and the risks and benefits of some pharmacologic interventions.
I use the term "sleep loss" advisedly, because this is the experience that many older patients report. The experience of sleep loss can include increased sleep latency; prolonged periods of being awake in bed; awakening during the night and being unable to resume sleep; interrupted rapid eye movement sleep, which is the sleep state in which dreams occur; early awakening; less sleep at night with more total time asleep during a 24-hour period; and daytime sleepiness and napping.
The changing sleeping patterns associated with aging, which may result in poorer daytime functioning and reduced participation in activities, can contribute to depression. Depression can also cause sleep disturbances. It is often difficult to ascertain the relationship between sleep loss and depression. Clinicians must always distinguish insomnia as a symptom from insomnia as a sleep disorder so that they can choose the most appropriate interventions. They also must determine the effects of sleep loss on driving and on executive and other functions as well as on perceived quality of life.
Many prevalence studies of insomnia have examined patient populations and caregivers in various medical settings. Such studies have used both subjective and objective measures of sleep disturbances. Methods of reporting and recording vary from study to study, as do the age ranges in the studies, the health and socioeconomic status of the subjects, and subjects' medication and substance use (6,7,8).
No large epidemiologic studies of the prevalence of insomnia verified by polysomnography among older adults living in the community have been undertaken (9). Several community surveys have been conducted; however, they are not directly comparable because of differences in methodology, definition of insomnia, and study population, and they will not be discussed here.
In one research study, a sample of 78 elderly people in the community who had sleep disturbances were given neuropsychological tests, were asked to keep daily sleep diaries, and underwent sleep monitoring in a laboratory (10). The results indicated that the participants' perceived sleep disturbances, as recorded in their diaries, were related to daytime performance deficiencies, as measured by tests of cognition, psychomotor speed, recall memory, and executive function. The sleep disturbances that were measured in the laboratory were related to deficiencies in memory, as measured by retention of a list of words. For patients' safety and well-being and to contain long-term health care costs, clinicians must be aware of their patients' daytime performance deficits.
We can assume that the incidence and prevalence of insomnia in all age groups have increased since the terrorist attacks of September 11. Fear, anxiety, bereavement, depression, and posttraumatic stress disorders take their toll on our ability to sleep with comfort. Experiences and images of the violence and destruction of the attacks, as well as fears about additional attacks of various kinds and about the economy, remain with us through the night. Older adults are likely to have lived through one or more wars. Some are Holocaust survivors, and many have served in the military and witnessed atrocities. Symptoms of posttraumatic stress that they had been able to overcome or deal with before the recent attacks may recur or intensify.
Only about 15 percent of patients who visit sleep disorder laboratories with complaints of insomnia are found by use of polysomnographic methods to have sleep disturbances that are not associated with extrinsic factors or other conditions (1). Changes associated with aging among healthy elderly people are included in this category.
Sleep disorders need to be considered in the differential diagnosis of complaints of insomnia by elderly patients. Also, when making treatment decisions, clinicians must distinguish occasional insomnia from chronic insomnia (11). Various types of sleep apnea (obstructive, central, and mixed), periodic limb movements, and restless leg syndrome have been found to increase with age. Sleep apnea is a cessation of airflow for at least ten seconds that produces brief arousal and is repeated throughout the night; it results in excessive daytime somnolence depending on the frequency of episodes. Periodic limb movement or nocturnal myoclonus, which causes frequent arousals, is often not noticed by patients; instead, these patients present with complaints about daytime sleepiness. However, a patient's bed partner may complain about the patient's excessive movements at night.
Restless leg syndrome consists of irresistible leg movements before the onset of sleep. The movements are in response to and seem to relieve a "creeping sensation." Although this syndrome is well described in the International Classification of Sleep Disorders: Diagnostic and Coding Manual (12), its relationship to aging is not clear. The syndrome can remit for long periods during a person's lifetime. Narcolepsy is a well-known sleep disorder with unique presenting symptoms that usually starts before late life.
Advanced sleep phase syndrome is a chronic inability to delay sleep onset. People with the syndrome fall asleep between 8 p.m. and 9 p.m. and awaken between 3 a.m. and 5 a.m. This phase advance is known to occur with normal aging. It can disrupt a person's lifestyle by interfering with work during the day and concentration and socialization in the evening. There has been some debate about whether advanced sleep phase syndrome is a sleep disorder or a normal phenomenon of aging. However, given that patients with the syndrome come to the clinician with a complaint to be addressed, and that nonpharmacologic intervention has been successful, it can be thought of and treated as a sleep disorder.
Delayed sleep and misperception of sleep state are disorders that may occur in late life, but they are not regarded as primarily associated with this life stage.
Many medical conditions and situations that contribute to insomnia occur with greater frequency in late life. Among them are cardiovascular diseases; pulmonary diseases, including chronic obstructive pulmonary disease; hypertension; diabetes; Alzheimer's disease and other dementias; Parkinson's disease; cancer; arthritis; pain from various sources; incontinence; gastroesophageal reflux disorder; and neuroendocrine disorders. Clinicians and researchers (13) seem to overlook the fact that hot flashes and decreased bladder control can and do awaken many older women at night, not only at the time of onset of menopause but also at any age thereafter (14).
Bereavement and relocation, financial changes, and insecurity frequently challenge older people. Insomnia must be taken into consideration in cases of depression, loneliness, lack of stimulation, anxiety, panic, posttraumatic stress, current life stresses, delayed recovery from a time zone transition, shift work, and caregiver burden. Among other psychiatric conditions that involve sleep disturbances are major depression, seasonal affective disorder, psychosis, delirium, bipolar disorder, and schizophrenia.
Clinicians should assess patients' consumption of alcohol, caffeine, nicotine, benzodiazepines, narcotics, and over-the-counter drugs as well as their use of the numerous medications prescribed for the medical conditions of late life. Alcohol often creates initial sedation followed by rebound wakefulness. Use of alcohol in combination with benzodiazepines has been associated with a high risk of suicide (11). Chronic use of benzodiazepines can be accompanied by hangover, rebound insomnia, confusion, falls, tolerance, addiction, and withdrawal. Because seizures may occur when benzodiazepines are discontinued abruptly, the dosage should be gradually tapered over several weeks. Most over-the-counter drugs for insomnia are antihistamines, either alone or combined with an analgesic. These drugs can cause anticholinergic side effects. Older adults tend to be considerably more sensitive to the anticholinergic properties of medications, which can contribute to cognitive impairment and poorer daytime functioning. Selective serotonin reuptake inhibitors, which are so frequently used to treat depression, panic, and obsessive-compulsive disorder, may also affect sleep adversely.
The choice of an intervention to alleviate insomnia among elderly patients depends on the results of a suitably detailed sleep assessment and consideration of conditions and situations that are associated with and contribute to insomnia. To aid in conducting a thorough assessment, clinicians can use sleep questionnaires, such as the standardized Pittsburgh Sleep Quality Index (15), or ask patients to complete a sleep diary each morning. Referral to a sleep laboratory for diagnosis or treatment may be indicated if a sleep disorder is suspected. Patients with medical or psychiatric conditions that the clinician cannot treat should be referred elsewhere, or the clinician should obtain consultation. The clinician should also take into account the medications taken by these patients.
We live in a quick-fix, pill-oriented, and often Internet-educated society. Patient and family education about the risks and benefits of prescribed or over-the-counter medications can greatly improve clinical outcome in the long run. However, the clinician must also establish a relationship that can motivate the patient to actively participate in nonpharmacologic interventions for symptomatic relief of insomnia and improved quality of life. Establishment of such a relationship can also help the clinician address patients' misperceptions of their sleep state and resulting complaints of insomnia.
A sleep environment that is noisy, cluttered, not completely dark, or too cold or too warm should be modified to be more inviting for restful sleep. Patients' problems with bed partners and the absence or availability of sexual activities also need to be addressed. Patients should be advised to go to bed and arise at about the same time each day. Use of stimulants such as coffee and nicotine should be avoided. Clinicians should encourage patients to eat a light evening snack with milk. Pleasurable exercise in the late afternoon or early evening, such as walking outside or on a treadmill, aerobics, yoga, or tai chi, or use of a therapeutic bright light during the day, may require a lifestyle change (3,16). Some patients may need to initiate a healthier diet.
Self-worth and self-motivation need to be developed gradually. Instructions about various interventions may be too much for some elderly persons to learn, integrate, and remember. Providing explicit, simple, written, and illustrated recommendations can be more helpful to some patients than sending them home with a prescription. Follow-ups should occur at least weekly at first. Trained office staff can follow up with telephone calls. Modern technology and the advent of distance learning have created new opportunities for follow-up and patient education. As soon as patients experience gratification from participation in treatment and are actively involved in making the modifications needed to attain improved sleep, the intervals between visits can be lengthened. The clinician must determine for each patient individually the habits that should be eliminated and acquired.
When relief of insomnia is the primary focus, a short-term course of medication treatment is desirable to afford the patient needed rest without creating dependence; during this time the clinician can also motivate the patient to attend to sleep hygiene.
Clinicians should describe the choices of insomnia medications and their risks and benefits to patients and their families. If a patient has taken any medication before, the clinician should obtain information about how long it was taken and its effects on sleep and daytime functioning. This information can guide the current choice.
A meta-analysis of the use of benzodiazepines in the treatment of insomnia confirmed that for some patients, their use is associated with increased duration of sleep, daytime drowsiness, lightheadedness, and impaired cognitive and psychomotor function the morning after use (17). Clinicians must consider the pharmacokinetics of a drug and the pharmacodynamic changes associated with aging, such as slower absorption, metabolism, and excretion. Sedative-hypnotics with a long half-life should not be prescribed for elderly patients. If patients are taking such medications that were prescribed during their younger years, the clinician should gradually switch to shorter-acting medications and another class of sedatives with different properties. Zolpidem and zalepon have a shorter half-life and can be taken in the middle of the night without the impairments or the cumulative effects associated with benzodiazepines.
Properties of the newer sedative-hypnotics other than their shorter half-life continue to be investigated, especially those that may cause adverse residual effects. For elderly patients, use of the lowest starting dosage is recommended; the dosage can be increased for patients who do not fully respond and who experience no side effects. The sedative qualities of some antidepressants and antipsychotics can be used judiciously if there are clinical indications for these medications.
Specialized knowledge is required to assess and treat sleep disturbances in late life. Such knowledge is rapidly expanding and must be integrated in training on all levels. Many advances have been made in treatments for various sleep disorders, and in this brief column most can be addressed only by a reminder that specialists can help, research is ongoing, and an abundant literature is available.
The author thanks Michael L. Perlis, Ph.D., for his helpful contributions.
Dr. Goldstein who is editor of this column, is associate professor of psychiatry in the division of geriatric psychiatry at the School of Medicine an Biomedical Sciences at the State University of New York at Buffalo. Send correspondence to her at the Erie County Medical Center, Department of Psychiatry, 462 Grider Street, Buffalo, New York 14215 ( firstname.lastname@example.org ).