Diana V. Jao MD
Cathy A. Alessi MD
More than 50% of community-dwelling older persons and >65% of long-term care facility residents experience sleeping difficulties. Fifty percent of community-dwelling older persons use over-the-counter or prescribed sleeping medications.
Two sleep states have been defined: nonrapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. NREM sleep consists of 4 stages. Stages 1 and 2 are considered light sleep; stage 1 is a transition period between wakefulness and sleep. Deep, restorative sleep occurs in stages 3 and 4. A normal night of sleep usually begins with NREM sleep; the first REM period occurs after 80 min or longer. NREM and REM then alternate throughout the night, with longer REM sleep periods as the night progresses.
Changes in both sleep structure (stages of sleep) and sleep pattern (amount and timing of sleep) occur with normal aging. Stage 1 and stage 2 sleep increases or remains unchanged with aging, whereas stage 3 and stage 4 sleep characteristically decreases. Changes in REM sleep with aging are controversial. Alterations in sleep pattern include decreased sleep efficiency (time asleep divided by time in bed), normal to decreased total sleep time, increased sleep latency (time to fall asleep), earlier bedtime and earlier morning awakening, more arousals during the night, and more daytime napping. The significance of these changes is unknown but may result in sleep complaints.
Patients may not report sleep complaints unless specifically asked by their health care provider, and presenting symptoms overlap significantly among common sleep disorders. One suggested algorithm for screening for sleep complaints, and an approach to diagnosis and treatment is shown in Figure 15-1.
ESSENTIALS OF DIAGNOSIS
Insomnia is often associated with daytime symptoms such as fatigue, irritability, and problems with concentration. Four common types of complaints related to insomnia include difficulty falling asleep, midsleep awakening, early morning awakening, and nonrestorative sleep.
Insomnia can be further classified based on the duration of symptoms. Transient (or acute) insomnia persists for no more than 1 week, and short-term (or subacute) insomnia lasts from 1 week to 3 mo. Both are generally considered an adjustment sleep disorder (ie, associated with an identifiable stressor). A longer duration of symptoms is usually regarded as chronic insomnia.
A detailed history is essential in determining the cause of insomnia. Key factors include recent stressors and symptoms of depression, anxiety, or other psychiatric disorders.
Instruments that can be helpful in the evaluation of insomnia include sleep questionnaires, at-home sleep
logs, symptom checklists, psychological screening tests, and interview of bed partners.
FIGURE 15-1. Algorithm for screening for sleep complaints and an approach to diagnosis and treatment.
Polysomnography is not indicated for the routine evaluation of transient or chronic insomnia. Other sleep diagnostic studies are available, such as portable sleep studies, wrist activity monitors, and static charge sensitive beds, but insufficient evidence exists to make specific recommendations about their usefulness in primary care.
The causes of insomnia are commonly psychiatric/psychological problems, symptoms related to underlying medical illnesses, effects of medications, or problems in the sleep–wake cycle. In fact, multiple factors may contribute to insomnia in the older patient. Excessive stress, depression, anxiety, and bereavement most characteristically result in early morning awakening, increased sleep latency, and more nighttime wakefulness.
Many medical conditions can interfere with sleep, including neuropathic pain, rheumatological conditions, malignancy pain syndromes, dyspnea resulting from cardiac or pulmonary illness, gastroesophageal reflux disease, and nighttime urination.
Medications reportedly account for 10–15% of cases of insomnia. Common offending agents include corticosteroids, respiratory medications (eg, pseudoephedrine, b2-agonists, theophylline), cardiovascular medications (eg, furosemide and quinidine), and antidepressants (eg, buproprion, fluoxetine, paroxetine, sertraline, and venlafaxine). Some antidepressants can induce somnolence or insomnia, depending on the dose (eg, desipramine, nortriptyline, and imipramine). Many other agents can disrupt sleep, such as cimetidine, phenytoin, caffeine, and nicotine. Caffeine is an ingredient in many nonprescription medications, sodas, candies, and teas, and many people are unaware that they are ingesting caffeine-containing products. Nighttime alcohol use can interfere with sleep because of effects leading to a lighter and shorter duration of sleep along with decreased REM sleep. Withdrawal from sedative–hypnotic agents also can lead to worsening insomnia.
Table 15-1. Examples of measures to improve sleep hygiene.
Relaxation techniques educate patients in recognizing and relieving tension and anxiety. However, relaxation techniques may be somewhat less effective in the older population than the other behavioral techniques mentioned.
Behavioral therapy appears to be as effective as medications for short-term insomnia. Chronic insomnia is best managed with behavioral interventions because of the greater likelihood of long-term effectiveness and lower risk of side effects.
Benzodiazepines and related drugs are commonly prescribed for sleep (Table 15-2). Long-acting benzodiazepines (eg, flurazepam) should not be used in older patients because of the risk of daytime carryover (sedation), falls, and fractures. Short- and intermediate-acting benzodiazepines can be used in older people; however, caution is warranted because of the risk of tolerance to the hypnotic effects of the medication and the potential for rebound insomnia on withdrawal. These agents may also result in an increased risk of falls, and their half-life can be longer in older people.
Nonbenzodiazepine hypnotics (eg, zolpidem and zaleplon) seem to have a better action profile, with fewer side effects, including less tolerance and less rebound insomnia on withdrawal, compared with benzodiazepines. Zolpidem (with a serum half-life of approximately 2.5 h) can be used for patients who have difficulty falling asleep. Zaleplon (with a serum half-life of 1 h) may be used to treat midsleep awakening if the patient has ≥4 h of additional sleep time before awakening. There is also reportedly no daytime carryover with this medication. However, caution is warranted in using even the newer sleeping medications for the management of chronic insomnia in the elderly.
Antidepressants with sedating side effects are also commonly used as sleeping medications. Sedating antidepressants are commonly prescribed at night for depressed patients who also report insomnia. Alternatively, nonsedating antidepressants taken during the daytime are sometimes prescribed for these depressed individuals, with the addition of a low dose of a sedating antidepressant (eg, 25–50 mg trazodone) at night for sleeping difficulty. These agents appear to have fewer problems with habituation compared with benzodiazepines, but response to this treatment is variable. The antidepressant amitriptyline is sedating but should not be used in older patients because of its strong anticholinergic side effects.
Table 15-2. Examples of commonly used prescription sleeping medications in older people.
Melatonin has also been used to promote sleep. In general, there is a decrease in melatonin levels with age and in individuals with Alzheimer's disease. Melatonin therapy appears to be effective in older insomniacs with demonstrated melatonin deficiency. However, melatonin measurements are not routinely available, and its use in insomniacs without melatonin deficiency is controversial. In addition, melatonin formulations are unregulated.
Chesson A et al: Practice parameters for the evaluation of insomnia. Sleep 2000;23:237. [PMID 10737341]
Morin CM et al: Behavioral and pharmacological therapies for late-life insomnia: A randomized controlled trial. JAMA 1999; 281:991. [PMID 10086433]
Morin CM et al: Nonpharmacological treatment of late-life insomnia. J Psychosom Res 1999;46:103. [PMID 10098820]
Sateia MJ et al: Evaluation of chronic insomnia. Sleep 2000;23: 243. [PMID 10737342]
EXCESSIVE DAYTIME SLEEPINESS
Problems with excessive daytime sleepiness may suggest a serious underlying sleep disorder. This excessive sleepiness is not simply the fatigue or tiredness that can occur with a variety of disorders. Excessive daytime sleepiness implies an irresistible desire to sleep and an inability to stay awake, even when it is quite abnormal to fall asleep. The 2 common conditions that are capable of inducing excessive daytime sleepiness in older people are sleep apnea and periodic limb movements disorder (PLMD). Restless legs syndrome (RLS), although related to PLMD, does not commonly present as excessive daytime sleepiness.
ESSENTIALS OF DIAGNOSIS
Sleep apnea is the cessation (or marked decrease) of airflow, which disrupts sleep. In obstructive sleep apnea (OSA), apnea is associated with the collapse of oropharyngeal structures, with continued ventilatory effort in the rib cage and abdomen.
Increased body mass index is the most important predictor of sleep apnea, although not all patients with sleep apnea are obese. Other risk factors include male gender and older age; prevalence rates of up to 40% are reported in people aged 65 and older. There is some evidence for a higher prevalence among individuals with dementia.
Excessive daytime sleepiness is the most common complaint in OSA. In addition, many patients complain of morning headache. The bed partner can be very helpful in reporting the typical symptoms of loud snoring, apnea, choking, and gasping sounds.
The clinical consequences of sleep apnea appear to relate to sleep fragmentation, hypoxia, and hypercapnia. Sleep apnea is associated with cardiovascular disease and increased morbidity and mortality rates. Other adverse consequences include cognitive impairment and a higher rate of motor vehicle accidents.
Several different screening methods for sleep apnea have been suggested. The “I SNORED” (Insomnia, Snoring, Not breathing/Nocturnal choking, Obesity [BMI >29], Restorative sleep, Excessive daytime hypersomnolence, and Drugs) test seems to have only modest predictive value in sleep laboratory studies (in which there is a high prevalence of sleep-disordered breathing). Its usefulness in a general medical population needs additional testing.
The gold standard for diagnosing OSA is nocturnal polysomnography. Based on the sleep study, an apnea–hypopnea index is calculated as the number of apnea and hypopnea events per hour of sleep.
Referral to a sleep specialist (in particular for polysomnography) is indicated in the evaluation of suspected sleep apnea. Some experts also recommend polysomnography when the initial diagnosis is uncertain or when the treatment is unsuccessful.
The severity of associated symptoms is considered in making treatment decisions because all treatments are associated with some consequences. Nonsurgical approaches include weight loss, avoidance of alcohol and sedative use, and avoidance of the supine sleeping position. Oral–dental devices that reposition the jaw or tongue are also available. Continuous positive airway pressure (CPAP) is quite effective. Some patients may find CPAP uncomfortable, but a variety of CPAP devices are available to meet patients' needs. For those who fail or are unable to tolerate CPAP, surgical revision can be considered. Surgical procedures offer mixed results, varying from ~30% with laser-assisted uvuloplasty to ~90% for mandibular-maxillary advancement.
PERIODIC LIMB MOVEMENT DISORDER & RESTLESS LEGS SYNDROME
The reported prevalence of periodic limb movements during sleep ranges from 20–60% among older adults.
PLMD can present as insomnia or excessive daytime sleepiness. Frequent sleep interruptions as a result of PLMD can cause nonrestorative sleep, daytime sleepiness, and fatigue.
Reported prevalence of RLS ranges from 2–15%. RLS generally causes insomnia, nighttime restlessness, and discomfort but can also lead to excessive daytime sleepiness when severe.
RLS and periodic limb movements often coexist; the latter are present in 80% of patients with RLS. The prevalence of these 2 disorders increases with age. The cause of neither condition is known, but increased age, positive family history, pregnancy, uremia, and low iron stores have been suggested as risk factors.
PLMD is characterized by recurring episodes of stereotypic rhythmic movements during sleep, generally involving the legs. The movements occur as often as every 20–40 s throughout the night.
RLS is characterized by an uncomfortable, irresistible urge to move the legs, usually associated with paresthesias and motor restlessness. The upper extremities are less commonly involved. There is usually a worsening of symptoms at rest and relief with motor activity. The symptoms are generally most pronounced in the evening or at night, occurring before the onset of sleep or occasionally with awakenings during the night. Patients may have difficulty falling asleep.
Polysomnography is used for the evaluation of PLMD.
The diagnosis of PLMD is reserved for individuals with periodic limb movements during sleep plus a sleep disturbance that is not explained by the presence of another disorder.
The diagnosis of RLS is made clinically based on the patient's symptoms, but PLMD cannot be adequately evaluated by history alone and requires polysomnographic confirmation.
The treatment of PLMD depends on the severity of symptoms and their impact on the patient's general well-being.
RLS may improve with leg stretching and other maneuvers. Pharmacotherapy should be considered for RLS when these maneuvers are ineffective or when symptoms are severe.
Choice of medication for these disorders should depend on evidence of effectiveness and comorbid conditions. Dopaminergic agents are the best studied agents for both RLS and PLMD and are considered by many as the treatment of choice in older patients. Treatment near bedtime with either carbidopa-levodopa (½ to full tablet of 25/100-mg tablets, or higher) or dopamine agonists (eg, pramipexole 0.125 mg, ropinirole 0.25-mg dose or higher) may be effective for both RLS and PLMD. Other dopaminergic agents are also likely effective. Oxycodone and propoxyphene have proven effective for both RLS and PLMD, but the risk of side effects with these agents limits their usefulness in the older patient. Clonazepam is effective for the treatment of PLMD and possibly RLS, but there is concern about risks of side effects with chronic use in older people. Other treatments to consider that have demonstrated some efficacy for RLS include gabapentin or iron supplementation (if ferritin level is low)
Narcolepsy is a disorder of recurrent, uncontrollable, brief episodes of sleep, which are often associated with hypnagogic or hypnopomic hallucinations, cataplexy, and sleep paralysis. This disorder rarely presents for the first time in old age.
The tetrad of symptoms for narcolepsy consists of excessive daytime sleepiness, cataplexy, sleep paralysis, and hypnagogic hallucinations.
Polysomnography typically reveals a shortened sleep latency (ie, time to fall asleep), sleep-onset REM (ie, REM sleep present soon after sleep onset), increased stage 1 sleep, and decreased sleep efficiency with increased number of arousals and awakenings. A structured daytime sleep study (the Multiple Sleep Latency Test) is also usually performed to determine the extent of daytime sleepiness and to identify sleep episodes with early onset of REM (ie, sleep-onset REM period).
Narcolepsy can be complicated by other sleep disorders Sleep apnea, periodic limb movements, and REM sleep behavior disorder can complicate narcolepsy.
Treatment consists of both nonpharmacological and pharmacological interventions. Nonpharmacological interventions involve maximizing nighttime sleep, supplemented by scheduled daytime naps, and avoiding emotional situations that precipitate attacks. However, patients usually require pharmacological treatment with stimulants such as methylphenidate or the nonstimulant agent modafinil and anticataplexy agents such as tricyclic antidepressants (eg, protriptyline, clomipramine) or selective serotonin reuptake inhibitors (eg, fluoxetine, venlafaxine, paroxetine).
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CIRCADIAN RHYTHM DISORDERS
The cause of a circadian rhythm sleep disorder may be obvious and transient, as in time zone change (jet lag) syndrome, or more prolonged. Correlations have been made between changes in circadian rhythms and advancing age.
Commonly, older people experience an advanced sleep phase, which leads to a pattern of an early bedtime and early morning awakening. The alteration in circadian rhythm can be marked in people who are bed bound. When the internal clock is completely desynchronized, the sleep–wake cycles become irregular, with sleep occurring during the day and wakefulness at night or alternating periods of sleep and wakefulness throughout the 24-h period.
Polysomnography may be indicated when a persistent circadian rhythm disorder is suspected.
Bright light exposure (eg, at ≥2500 lux) in the evening or late afternoon has been recommended as a treatment for an advanced sleep phase. Melatonin has been used to prevent and treat zone change syndrome and appears to have some efficacy in doses of 0.5–5 mg taken close to the target bedtime of the destination.
REM SLEEP BEHAVIOR DISORDER
ESSENTIALS OF DIAGNOSIS
REM sleep behavior disorder (RBD) is an REM parasomnia. Although rare in the general population, it can present in late life and occurs more commonly in men than women.
The normal muscle atonia present during REM sleep is lost. Patients act out their lively dreams with forceful movements and behaviors during sleep. They usually present for medical care as a result of injury to themselves or their bed partners, ranging from ecchymoses to fractures. RBD has been associated with multiple central nervous system disorders, including dementia, Parkinson's disease, and progressive supranuclear palsy. RBD may precede the typical symptoms of these conditions by as many as 10 years. In addition, medications used to treat these disorders, such as cholinergic agents for Alzheimer's disease, seligiline for Parkinson's disease, and some antidepressants, have been associated with RBD.
Polysomnography is used to confirm the diagnosis and to rule out other conditions, such as sleep apnea.
RBD has been successfully treated with removal of the offending agent or administration of clonazepam, which has been shown to effectively suppress the abnormal
sleep behaviors in up to 90% of cases. The usual starting dose of clonazepam is 0.5 mg at bedtime, increasing to 1 mg as needed. Tolerance to the therapeutic effects of clonazepam for RBD does not appear to develop over time. However, the diagnosis of RBD must be made polysomnographically before instituting chronic treatment, particularly in older patients.
SLEEP PROBLEMS IN SPECIAL POPULATIONS
Sleep Pattern in Dementia
Most research on sleep problems with dementia has focused on Alzheimer's disease. Compared with older people without dementia, those with dementia have more sleep disruption and arousals during the night along with more stage 1 and less stage 3 and stage 4 sleep. Lower sleep efficiency is also noted. Sundowning, a worsening of confusion or problematic behaviors at night, is sometimes classified as a sleep problem and is present in 12–20% of patients with dementia.
Polysomnography does not appear to be particularly effective in the diagnosis of sleep complaints related to dementia and other psychiatric disorders.
Sleep Disturbance in Nursing Home Residents
The common pattern of sleep disturbance among nursing home residents involves frequent nighttime arousals. Many factors seem to affect quality of sleep, including multiple physical illnesses and medications that can interfere with sleep, debility and inactivity, increased prevalence of primary sleep disorders, minimal sunlight exposure, and environmental factors, including frequent nighttime noise and light and disruptive nighttime nursing care activities.
Alessi CA, Schnelle JF: Approach to sleep disorders in the nursing home setting. Sleep Med Rev 2000;4:45. [No PMID available]
RELEVANT WORLD WIDE WEB SITES
American Academy of Sleep Medicine: http://www.aasmnet.org
National Institutes of Health National Center on Sleep Disorders Research: http://www.nhlbi.nih.gov/sleep