Insomnia: An Overview of Sleep Disorders in the Geriatric Patient

For the elderly, achieving a good night's sleep may prove to be quite a challenge. In this age group, sleep-related disorders are quite common. It is a typical assumption that, as people age, they require less sleep. In fact, they experience a lesser quality of sleep than their younger counterparts, with more frequent awakenings. According to a Consensus Development Conference Statement from the National Institutes of Health, sleep disturbances afflict more than one half of the over-65 population living at home and about two thirds of those who live in long-term care facilities.¹ Sleep disturbances consist of (1) trouble falling asleep, (2) either difficulty in waking or waking too early, (3) a need to nap, or (4) not achieving enough rest.² Although sleep-related problems generally are not life-threatening, they can result in fatigue and accidents. They affect a person's ability to function in normal activities and ultimately impact quality of life.

Definitions

Insomnia is defined as a subjective complaint related to falling asleep, maintaining adequate sleep, or not feeling rested such that lack of sleep causes impairment in the ability to function in work-related or social activities.³ In the geriatric patient, insomnia may be caused by obstructive sleep apnea, restless legs syndrome, adverse effects of medications, or other medical or psychiatric conditions.⁴ Circadian-rhythm disorders may account for altered sleep patterns, because the sleepiness and need to nap during the day may stem from a disruption of the sleep/wake cycle.⁵

Transient insomnia usually afflicts those with no history of sleep disorder. It is commonly due to temporary stress, jet lag, or the sleeping environment. This form of insomnia generally is short-term (resolving within a few days).⁶

Chronic insomnia usually lasts 3 weeks or longer and can exacerbate many medical or psychiatric conditions. It also can lead to confusion and impairment of cognition. It can ultimately impact a patient's social life, cause mood disturbances, and increase the risk of accidents.

Factors Involved in Sleep Disorders

As previously stated, disorders in the elderly may occur as a result of other underlying conditions, which generally are chronic in nature.³ Because approximately 80% of persons over the age of 75 suffer from at least 1 chronic disease and 40% suffer from 2 or more diseases, impaired sleep can occur quite frequently in this age group.⁷

Aging and Insomnia

Advanced age brings about sleep deterioration, encompassing the time it takes to fall asleep, a decrease in overall sleep duration, and an increase in the number of awakenings.⁸ A study conducted by the Department of Psychiatry of New York Hospital, Cornell Medical Center, examined the role of sleep disorders in a family's decision to institutionalize aging relatives. The study showed that, in approximately 70% of the cases cited, family members named sleep problems as the deciding factor in institutionalizing aging relatives because of the effect they had on the caregivers' sleep as well.⁹

Physiologic and Psychiatric Disorders

Medical illnesses such as chronic pain, respiratory problems, or cardiovascular problems, as well as mental illnesses, seem to be factors in age-related sleep disorders (Table 1).¹⁰ The incidence of insomnia increases with advancing age. For instance, patients who are treated for an underlying medical condition also may fall into a depressive state, which causes sleep problems. Lifestyle changes?common in the elderly as a result of their work status, retirement, and reduction in income?also may result in depression and anxiety. Other factors leading to psychiatric disorders include the loss of a spouse, friend, or family member; hospitalization; feelings of neglect; and even the emotional adjustment of leaving familiar surroundings when moving to a long-term care facility.

Medication

Evaluation of medication use, including psychotropic medications and OTC remedies, is essential in assessing sleep disorders. Elderly persons often are treated by several physicians, who may prescribe medications with a potential for drug interactions. The elderly may use OTC products, vitamins, or herbal products inappropriately. In fact, many medications regularly prescribed for the elderly can result in insomnia (Table 2). Alcohol, caffeine, and nicotine should be avoided by patients who are experiencing insomnia. Whereas alcohol may cause drowsiness initially, it can cause fragmented sleep and increased wakefulness in the second half of the sleep cycle. Furthermore, the metabolism of alcohol slows down with age, causing excessive sedation.¹¹

Goals of Treatment

Treatment should begin with a medical history and a comprehensive evaluation of the patient, whereby problems in sleep can be defined and medical or psychological conditions addressed. Nonpharmacologic methods should be considered first as a means toward restoring a normal sleep pattern. A number of routines can be established to prevent insomnia (eg, establishing a consistent time to go to bed, awaken, and eat; avoiding alcohol and caffeine after noon; creating a suitable sleep environment; and avoiding daytime naps).

Pharmacotherapy

Pharmacologic therapy with hypnotic agents generally is implemented in the elderly when other methods have failed. When choosing an agent, it is important to keep in mind its onset of action,¹² half-life, side-effect profile, and degree of impairment of daytime activities. Changes in metabolism in the elderly also dictate caution when prescribing an agent. For example, because there is a decrease in body water and an increase in total body fat in older patients, fat-soluble drugs such as flurazepam (Dalmane; Roche) and diazepam (Valium; Roche) can cause a delay in clearance and prolong the effect of the drug.¹³ Drug accumulation also can result due to alterations in hepatic and renal function.

Benzodiazepines are widely used to treat insomnia, because they decrease sleep latency as well as awakenings.¹⁴ Yet, they vary in terms of half-life, onset of action, and side effects. Triazolam (Halcion; Upjohn), a short-acting agent often prescribed for insomnia, has been associated with such adverse effects as agitation and amnesia, and it may cause rebound insomnia and anxiety. Estazolam (ProSom; Abbott) and temazepam (Restoril; Sandoz) are intermediate in action, with no active metabolites, and are frequently prescribed. Flurazepam is longacting, with active metabolites, and it should be avoided. Side effects of these drugs as a class include daytime sedation, confusion, dizziness, and amnesia.¹⁰ Because abrupt discontinuation of these agents can cause withdrawal symptoms, it is recommended that they be tapered slowly.

Newer hypnotic agents?zolpidem (Ambien; Searle) and zaleplon (Sonata; Wyeth)?also are prescribed for insomnia. These drugs, although not benzodiazepines, act selectively at the benzodiazepine receptor. Zolpidem has a duration of action of 6 to 8 hours and is associated with a decrease in residual sedation. The recommended daily dose is 10 mg and 5 mg in the elderly.¹⁵ Adverse effects include dizziness, headache, and gastrointestinal complaints. Zaleplon, a pyrazolopyrimidine, has a quick onset of action, with minimal residual sedation. As with zolpidem, the recommended dose is 5 mg in the elderly.¹⁶

Other therapeutic options include antidepressants and antihistamines. Tricyclic antidepressants, however?such as amitriptyline (Elavil; Zeneca) and doxepin (Sinequan; Roerig)?may cause cardiac episodes, orthostatic hypotension, and confusion^13,14; therefore, patient monitoring is important. The use of antihistamines, including OTC remedies, has limitations due to their anticholinergic effects.⁵ Herbal supplements also used include melatonin, a hormone produced by the pineal gland, and valerian.

Conclusion

The normal aging process frequently leads to insomnia in the elderly. The initial evaluation should address medical conditions, medications, or sleep habits. Once a pharmacologic agent is deemed necessary, it should be initiated at the lowest dose, taking into consideration underlying medical and psychiatric conditions, pharmacokinetic parameters, and the side-effect profile of the drug.

Dr. Pelegrin is a clinical pharmacy writer practicing in the community pharmacy setting in Miami, Fla.

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