Insomnia



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Am Fam Physician. 1999 Apr 1;59(7):1911-1916.

  See related patient information handout on insomnia, written by the authors of this article.

Insomnia is a common complaint with potentially significant medical and psychologic complications. In some cases insomnia presents as a symptom of another underlying medical, psychiatric or environmental condition. In these cases, management of insomnia depends on accurate diagnosis and successful treatment of the underlying condition. In other cases, insomnia is a primary disorder requiring direct treatment. Pharmacologic treatments include nonprescription medications, sedating tricyclic anti-depressants, benzodiazepines and related drugs. Behavior management methods that may be administered in the office setting include stimulus control therapy, sleep restriction therapy and sleep hygiene education. Although prescription medications and behavior therapy have similar short-term efficacy, behavior interventions are recommended as the first line of treatment for primary insomnia because of their greater safety and long-term efficacy.

Insomnia affects approximately 10 to 17 percent of the adult U.S. population.1,2 In contrast to the occasional sleepless night experienced by most people, insomnia may be a persistent or recurrent problem3,4 with serious medical complications, including anxiety, depression and multiple physical complaints.46 The total cost of insomnia, including treatment, lost productivity and insomnia-related accidents, may exceed $100 billion per year.7

Definition and Etiology

Insomnia may be viewed as both a symptom and a syndrome. As a symptom, insomnia may develop secondary to an underlying medical, psychiatric or environmental factor. Several of these causal factors are presented in Table 1. In these cases, it is essential to identify and treat the underlying cause of insomnia. Misidentification of the underlying cause may result in ineffective or even harmful interventions, such as prescribing a benzodiazepine for patients with insomnia that is due to sleep apnea or substance abuse. In cases of symptomatic insomnia, the target of treatment is not the sleeplessness itself but the underlying disorder.

TABLE 1

Common Causes of Insomnia

Medical causes

Nonprescription drugs

Caffeine

“Diet pills” (e.g., those including pseudoephedrine, phenylpropanolamine)

Nicotine

Prescription drugs

Methylphenidate (Ritalin)

Theophylline

Albuterol (Ventolin)

Quinidine (Cardioquin)

Pemoline (Cylert)

Dextroamphetamine (Dexedrine)

Pseudoephedrine (Novafed)

Phenylephrine (Neo-Synephrine)

Phenylpropanolamine (Entex)

Selective serotonin reuptake inhibitors

Medical conditions

Primary sleep disorders (sleep apnea, periodic limb movement disorder, nocturnal myoclonus, restless legs syndrome)

Pain from any source or cause

Drug or alcohol intoxication or withdrawal

Thyrotoxicosis

Dyspnea from any cause

Psychologic causes

Depression

Anxiety

Life stressors

Bedtime worrying

Conditioning (associating the bed with wakefulness)

Mania or hypomania

Environmental causes

Bedroom too hot or too cold

Noise

Eating, exercise, caffeine or alcohol use before bedtime

Jet lag

Shift work

Daytime napping

TABLE 1   Common Causes of Insomnia

View Table

TABLE 1

Common Causes of Insomnia

Medical causes

Nonprescription drugs

Caffeine

“Diet pills” (e.g., those including pseudoephedrine, phenylpropanolamine)

Nicotine

Prescription drugs

Methylphenidate (Ritalin)

Theophylline

Albuterol (Ventolin)

Quinidine (Cardioquin)

Pemoline (Cylert)

Dextroamphetamine (Dexedrine)

Pseudoephedrine (Novafed)

Phenylephrine (Neo-Synephrine)

Phenylpropanolamine (Entex)

Selective serotonin reuptake inhibitors

Medical conditions

Primary sleep disorders (sleep apnea, periodic limb movement disorder, nocturnal myoclonus, restless legs syndrome)

Pain from any source or cause

Drug or alcohol intoxication or withdrawal

Thyrotoxicosis

Dyspnea from any cause

Psychologic causes

Depression

Anxiety

Life stressors

Bedtime worrying

Conditioning (associating the bed with wakefulness)

Mania or hypomania

Environmental causes

Bedroom too hot or too cold

Noise

Eating, exercise, caffeine or alcohol use before bedtime

Jet lag

Shift work

Daytime napping

Primary insomnia is sleeplessness that is not attributable to a medical, psychiatric or environmental cause. The diagnostic criteria for primary insomnia from the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) are presented in Table 2.8 The diagnosis is based on the patients' subjective reports of their sleep patterns, including complaints of nonrestful sleep as well as difficulties with sleep onset or maintenance. Symptom severity must be sufficient to result in significant emotional distress or impairment in functioning. The disorder is chronic by definition (i.e., lasting at least one month).

TABLE 2

DSM-IV Diagnostic Criteria for Primary Insomnia

A. The predominant complaint is difficulty initiating or maintaining sleep, or nonrestorative sleep, for at least 1 month.

B. The sleep disturbance (or associated daytime fatigue) causes clinically significant distress or impairment in social, occupational, or other important areas of functioning.

C. The sleep disturbance does not occur exclusively during the course of narcolepsy, breathing-related sleep disorder, circadian rhythm sleep disorder, or a parasomnia.

D. The disturbance does not occur exclusively during the course of another mental disorder (e.g., major depressive disorder, generalized anxiety disorder, a delirium).

E. The disturbance is not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication) or a general medical condition.


Reprinted with permission from the American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 4th ed. Washington, D.C.: American Psychiatric Association, 1994:557. Copyright 1994.

TABLE 2   DSM-IV Diagnostic Criteria for Primary Insomnia

View Table

TABLE 2

DSM-IV Diagnostic Criteria for Primary Insomnia

A. The predominant complaint is difficulty initiating or maintaining sleep, or nonrestorative sleep, for at least 1 month.

B. The sleep disturbance (or associated daytime fatigue) causes clinically significant distress or impairment in social, occupational, or other important areas of functioning.

C. The sleep disturbance does not occur exclusively during the course of narcolepsy, breathing-related sleep disorder, circadian rhythm sleep disorder, or a parasomnia.

D. The disturbance does not occur exclusively during the course of another mental disorder (e.g., major depressive disorder, generalized anxiety disorder, a delirium).

E. The disturbance is not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication) or a general medical condition.


Reprinted with permission from the American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 4th ed. Washington, D.C.: American Psychiatric Association, 1994:557. Copyright 1994.

The etiology of primary insomnia relates in part to psychologic conditioning processes.8 Most cases of insomnia develop initially in response to a medical or psychosocial stressor. As sleeplessness persists, the patient begins to associate the bed with wakefulness and heightened arousal rather than sleep. The patient may fall asleep easily outside the bedroom (i.e., when watching television or reading in the living room) but feel wide awake in bed. It is important to note that once this conditioning process has occurred, the patient's insomnia may persist long after the original psychosocial or medical stressor has been resolved.

Evaluation

A thorough clinical interview is critical for effective treatment of insomnia. A variety of medical, psychosocial and environmental factors that may cause insomnia must be ruled out (Table 1). Collateral interviews with the patient's sleep partner are also useful9,10 to gather information regarding nocturnal events of which the patient may be unaware, such as apneic episodes, periodic limb movements, nocturnal myoclonus or fitful sleep.

An extensive review of the medical conditions that can cause insomnia is beyond the scope of this article. However, medical conditions should be considered in the evaluation of patients with sleeplessness.

A sleep diary is also important in the evaluation of insomnia.9,10 A sleep diary is a questionnaire completed by the patient each morning to describe the previous night's sleep. Variables assessed by the diary may include time entering and leaving bed, sleep latency, total sleep time, number of awakenings and subjective assessment of the restfulness of sleep. Data from the sleep diary may help minimize distortions in sleep information recalled in the physician's office.

The usefulness of polysomnographic evaluation in cases of primary insomnia has been questioned because of its cost and the possibility that insomnia may be specific to the patient's usual sleep environment.9 However, polysomnographic evaluation may be considered when sleep-disordered breathing or periodic limb movement disorder is suspected or when behavior and psychopharmacologic treatments are unsuccessful.11 It is not recommended for the routine evaluation of insomnia.11

Pharmacologic Treatment of Insomnia

NONPRESCRIPTION DRUGS

A recent community-based sample of young adults indicated that approximately 10 percent had used nonprescription medications and 13 percent had used alcohol in the past year to improve sleep.1 The active agent in many over-the-counter medications (such as Sleep-Eze, Sominex and Nytol) is one of the sedating antihistamines (e.g., diphenhydramine [Benadryl], doxylamine [Unisom]). While these medications are generally safe, they have anticholinergic side effects such as urinary retention, dry mouth and constipation. The half-life of these agents is variable, and their use can result in residual drowsiness. Both nonprescription medications and alcohol are only minimally effective in inducing sleep and may reduce sleep quality.10 Consequently, patients should be discouraged from using them on a routine basis.

MELATONIN

Melatonin is currently a popular remedy for insomnia. An entire issue of the Journal of Biological Rhythms (December 1997) was devoted to this topic. The family physician should anticipate questions from patients regarding this compound and its use as a sleep aid. Melatonin is a hormone secreted by the pineal gland and is purported to have sleep-inducing properties.12 Although the effectiveness of melatonin remains controversial,13,14 it has received attention in the treatment of insomnia caused by circadian schedule changes (i.e., jet lag, shift work). In these circumstances, melatonin successfully hastens adaptation to the new circadian schedule. Its effectiveness in cases of chronic insomnia that are not related to circadian schedule shifts is less clear.15

No serious adverse effects have been reported from the short-term use of melatonin. However, no systematic long-term studies of the use of melatonin have been reported.13 Although melatonin is a naturally occurring substance in the human body, its ingestion in pharmacologic dosages has the potential to induce undesirable side effects, such as sleep disruption, daytime fatigue, headache, dizziness and increased irritability.12 In addition, standards of quality regarding purity, concentration and absence of harmful impurities are not regulated for melatonin as they are with prescription products. At this time, the use of melatonin for short-term adaptation to jet lag or shift changes would appear reasonable. However, given the availability of other safe and effective treatments for non–circadian-related insomnia, there is little basis for recommending the use of melatonin in these forms of insomnia until additional studies have been completed.

PRESCRIPTION DRUGS

The benzodiazepines are the medications most commonly prescribed for insomnia and have demonstrated efficacy in short-term treatment.2 However, the wide range of metabolic half-life in these medications produces a variety of side effects, including physical dependence, sedation and impairment of motor abilities. Longer-acting medications such as flurazepam (Dalmane) and quazepam (Doral) are less likely to produce rebound insomnia but more likely to cause daytime sleepiness. Shorter-acting drugs such as triazolam (Halcion), temazepam (Restoril) and zolpidem (Ambien) are effectively eliminated by morning, decreasing the likelihood of residual daytime effects.

Triazolam has been removed from the market in several European countries because of multiple problems, including dependency, transient psychotic reactions, anterograde amnesia and rebound insomnia.16 Although zolpidem is not a benzodiazepine per se, it acts at the benzodiazepine receptor sites, and there are concerns that it may carry the same risk of dependence as the benzodiazepines.10

The traditional duration of hypnotic drug use for treatment of insomnia has been four weeks. Long-term use increases the likelihood of habituation and problematic withdrawal symptoms. Concerns about the use of benzodiazepines resulted in a drop of approximately 30 percent in benzodiazepine prescriptions for the treatment of insomnia between 1987 and 1991.17

A class of drugs that may offer an alternative in the treatment of insomnia is the sedating tricyclic antidepressants (amitriptyline [Elavil] and doxepin [Sinequan]). These medications are effective soporific agents even when given in low dosages that would be considered subtherapeutic for the treatment of depression. There is some concern that if these agents are used in the elderly, the risk of falling is increased. In addition, their use raises concerns regarding anticholinergic, cardiovascular and other side effects, along with the danger of potentially lethal overdose. Trazodone (Desyrel) may offer a safer alternative, although priapism is a potential side effect with this medication. Some commonly used medications and their dosages are listed in Table 3.

TABLE 3

Medications Used in the Treatment of Insomnia

Agent Dosage Peak action Half-life Cost (generic)*

Estazolam (Prosom)

1 to 2 mg

2 hours (0.5 to 6 hours)

10 to 24 hours

$28.50

Flurazepam (Dalmane)

15 to 30 mg

0.5 to 1 hour

2 to 3 hours (47 to 100 hours for metabolite)

16.50 (5.50 to 18.00)

Oxazepam (Serax)

10 to 15 mg

3 hours

5 to 10 hours

23.00 (6.50 to 10.50)

Quazepam (Doral)

7.5 to 15 mg

2 hours

41 hours (47 to 100 hours for metabolite)

49.00

Temazepam (Restoril)

7.5 to 30 mg

1.2 to 1.6 hours

3.5 to 18.4 hours (9 to 15 hours for metabolite)

20.00 (14.00 to 16.00)

Triazolam (Halcion)

0.125 to 0.5 mg

1 to 2 hours

1.5 to 5.5 hours

22.50 (16.00 to 23.00)

Zolpidem (Ambien)†

5 to 10 mg

1.6 hours

2.5 hours

43.00


note: This selected list of benzodiazepines includes all those with U.S. Food and Drug Administration–approved labeling for insomnia.

*—Estimated cost to the pharmacist for 30 tablets/capsules at lowest usual dosage based on average wholesale prices (rounded to the nearest half dollar) in Red book. Montvale, N.J.: Medical Economics Data, 1998. Cost to the patient will be higher, depending on prescription filling fee.

†—Not a true benzodiazepine but acts at the benzodiazepine receptor sites.

TABLE 3   Medications Used in the Treatment of Insomnia

View Table

TABLE 3

Medications Used in the Treatment of Insomnia

Agent Dosage Peak action Half-life Cost (generic)*

Estazolam (Prosom)

1 to 2 mg

2 hours (0.5 to 6 hours)

10 to 24 hours

$28.50

Flurazepam (Dalmane)

15 to 30 mg

0.5 to 1 hour

2 to 3 hours (47 to 100 hours for metabolite)

16.50 (5.50 to 18.00)

Oxazepam (Serax)

10 to 15 mg

3 hours

5 to 10 hours

23.00 (6.50 to 10.50)

Quazepam (Doral)

7.5 to 15 mg

2 hours

41 hours (47 to 100 hours for metabolite)

49.00

Temazepam (Restoril)

7.5 to 30 mg

1.2 to 1.6 hours

3.5 to 18.4 hours (9 to 15 hours for metabolite)

20.00 (14.00 to 16.00)

Triazolam (Halcion)

0.125 to 0.5 mg

1 to 2 hours

1.5 to 5.5 hours

22.50 (16.00 to 23.00)

Zolpidem (Ambien)†

5 to 10 mg

1.6 hours

2.5 hours

43.00


note: This selected list of benzodiazepines includes all those with U.S. Food and Drug Administration–approved labeling for insomnia.

*—Estimated cost to the pharmacist for 30 tablets/capsules at lowest usual dosage based on average wholesale prices (rounded to the nearest half dollar) in Red book. Montvale, N.J.: Medical Economics Data, 1998. Cost to the patient will be higher, depending on prescription filling fee.

†—Not a true benzodiazepine but acts at the benzodiazepine receptor sites.

Psychologic Treatment of Insomnia

STIMULUS CONTROL THERAPY

The purpose of stimulus control therapy is to re-establish the connection between the bed and sleep by prohibiting the patient from engaging in non-sleep activities while in bed.10,18  The instructions given to the patient are presented in Table 4. This treatment is easily administered by the family physician and has demonstrated efficacy.18

TABLE 4

Stimulus Control Instructions

1. Go to bed only when sleepy.

2. Do not use the bed for any activities other than sleep (or sex). Do not read, watch television or eat in bed.

3. If you do not fall asleep in about 15 to 20 minutes, leave the bedroom. Return to bed when you are sleepy.

4. Repeat step 3 as many times as needed until sleep occurs within 15 to 20 minutes of returning to bed.

5. Get up at the same time each day regardless of how much you slept.

6. Do not nap during the day or sleep in locations other than bed.

TABLE 4   Stimulus Control Instructions

View Table

TABLE 4

Stimulus Control Instructions

1. Go to bed only when sleepy.

2. Do not use the bed for any activities other than sleep (or sex). Do not read, watch television or eat in bed.

3. If you do not fall asleep in about 15 to 20 minutes, leave the bedroom. Return to bed when you are sleepy.

4. Repeat step 3 as many times as needed until sleep occurs within 15 to 20 minutes of returning to bed.

5. Get up at the same time each day regardless of how much you slept.

6. Do not nap during the day or sleep in locations other than bed.

SLEEP RESTRICTION THERAPY

Sleep restriction therapy involves limiting the amount of time the patient spends in bed to the actual amount of time the patient usually spends sleeping.10,18 For example, if the patient normally spends only four hours per night asleep, then the total amount of time spent in bed per night would be limited to four hours, regardless of the actual amount of time spent sleeping. This allows a sleep debt to accumulate that results in more rapid sleep onset on subsequent nights. When the patient is spending 85 to 90 percent of the time in bed asleep, the allowable time spent in bed is increased. Although somewhat more complex for the family physician to describe, sleep restriction therapy is an effective treatment for insomnia.18

SLEEP HYGIENE EDUCATION

Sleep hygiene education consists of a set of instructions regarding environment and lifestyle factors that affect sleep.18  Table 5 presents a typical set of sleep hygiene instructions. Sleep hygiene is not effective as the sole intervention for insomnia18 but is recommended as an adjunct to other forms of therapy.

TABLE 5

Instructions for Improvement of Sleep Hygiene

1. Decrease or eliminate the use of caffeine, especially after noon.

2. Do not use tobacco or alcohol near bedtime.

3. Avoid heavy meals close to bedtime. However, a light snack at bedtime may promote sleep.

4. Avoid vigorous exercise within 3 to 4 hours of bedtime.

5. Establish a regular schedule for going to bed and getting up. Avoid daytime naps.

6. Keep the bedroom at a comfortable temperature and minimize light and noise.


Adapted with permission from Van Brunt DL, Riedel BW, Lichstein KL. Insomnia. In: Hasselt VB, Hersen M, eds. Sourcebook of psychological treatment manuals for adult disorders. New York: Plenum, 1996:539–56.

TABLE 5   Instructions for Improvement of Sleep Hygiene

View Table

TABLE 5

Instructions for Improvement of Sleep Hygiene

1. Decrease or eliminate the use of caffeine, especially after noon.

2. Do not use tobacco or alcohol near bedtime.

3. Avoid heavy meals close to bedtime. However, a light snack at bedtime may promote sleep.

4. Avoid vigorous exercise within 3 to 4 hours of bedtime.

5. Establish a regular schedule for going to bed and getting up. Avoid daytime naps.

6. Keep the bedroom at a comfortable temperature and minimize light and noise.


Adapted with permission from Van Brunt DL, Riedel BW, Lichstein KL. Insomnia. In: Hasselt VB, Hersen M, eds. Sourcebook of psychological treatment manuals for adult disorders. New York: Plenum, 1996:539–56.

Pharmacologic vs. Psychologic Treatment

Both pharmacologic and psychologic treatments are effective in the management of insomnia, reducing sleep onset latency by 15 to 30 minutes and reducing the number of awakenings by one to three episodes per night.10 Although pharmacologic agents act more reliably in the short term, psychologic approaches produce more durable results10 without the side effects associated with medications. Few studies have evaluated the effectiveness of combined pharmacologic and psychologic treatments, but some studies suggest that patients who use sleep medications benefit less from psychologic interventions.19,20

Since the efficacy of pharmacologic and psychologic treatments for insomnia is comparable, it is recommended that psychologic approaches be used as the first-line treatment whenever feasible, given their greater safety and long-term efficacy.

The Authors

MARK EDDY, PH.D., is an assistant professor in the Department of Family Medicine at Wright State University School of Medicine, Dayton, Ohio. He is the director of behavioral science at the St. Elizabeth Family Practice Residency at the Franciscan Medical Center–Dayton Campus. He received his doctorate in clinical psychology from Michigan State University, East Lansing.

GORDON S. WALBROEHL, M.D., is professor and vice chair of academic and community development in the Department of Family Medicine at Wright State University. He received his medical degree from the New Jersey College of Medicine and Dentistry, Newark, and completed a residency at Malcolm Grow Medical Center at Andrews Air Force Base, Washington, D.C.

Address correspondence to Mark Eddy, Ph.D., Division of Applied Psychology, Department of Family Medicine, Wright State University School of Medicine, 601 Edwin C. Moses Blvd., Dayton, Ohio 45408. Reprints are not available from the authors.

REFERENCES

1. Johnson EO, Roehrs T, Roth T, Breslau N. Epidemiology of alcohol and medication as aids to sleep in early adulthood. Sleep. 1998;21:178–86.

2. Nowell PD, Mazumdar S, Buysse DJ, Dew MA, Reynolds CF 3d, Kupfer DJ. Benzodiazepines and zolpidem for chronic insomnia: a meta-analysis of treatment efficacy. JAMA. 1997;278:2170–7.

3. Mendelson WB. Long-term follow-up of chronic insomnia. Sleep. 1995;18:698–701.

4. Kales JD, Kales A, Bixler EO, Soldatos CR, Cadieux RJ, Kashurba GJ, et al. Biopsychobehavioral correlates of insomnia, V: clinical characteristics and behavioral correlates. Am J Psychiatry. 1984;141:1371–6.

5. Ford DE, Kamerow DB. Epidemiologic study of sleep disturbances and psychiatric disorders. An opportunity for prevention? JAMA. 1989;262:1479–84.

6. Mellinger GD, Balter MB, Uhlenhuth EH. Insomnia and its treatment. Prevalence and correlates. Arch Gen Psychiatry. 1985;42:225–32.

7. Stoller MK. Economic effects of insomnia. Clin Ther. 1994;16:873–97.

8. Diagnostic and statistical manual of mental disorders. 4th ed. Washington, D.C.: American Psychiatric Association, 1994:553–7.

9. Lichstein KL, Riedel BW. Behavioral assessment and treatment of insomnia: a review with an emphasis on clinical application. Behavior Therapy. 1994;25:659–88.

10. Kupfer DJ, Reynolds CF 3d. Management of insomnia. N Engl J Med. 1997;336:341–6.

11. Practice parameters for the use of polysomnography in the evaluation of insomnia. Standards of Practice Committee of the American Sleep Disorders Association. Sleep. 1995;18:55–7.

12. Zhdanova IV, Lynch HJ, Wurtman RJ. Melatonin: a sleep-promoting hormone. Sleep. 1997;20:899–907.

13. Sack RL, Hughes RJ, Edgar DM, Lewy AJ. Sleep-promoting effects of melatonin: at what dose, in whom, under what conditions, and by what mechanisms? Sleep. 1997;20:908–15.

14. Mendelson WB. A critical evaluation of the hypnotic efficacy of melatonin. Sleep. 1997;20:916–9.

15. Mendelson WB. Efficacy of melatonin as a hypnotic agent. J Biol Rhythms. 1997;12:651–6.

16. Eisendrath SJ. Psychiatric disorders. In: Tierney LM Jr, McPhee SJ, Papadakis MA, eds. Current medical diagnosis and treatment. 38th ed. Stamford, Conn.: Appleton & Lange, 1999:1030.

17. Walsh JK, Engelhardt CL. Trends in the pharmacologic treatment of insomnia. J Clin Psychiatry. 1992;53:10–7.

18. Morin CM, Culbert JP, Schwartz SM. Nonpharmacological interventions for insomnia: a meta-analysis of treatment efficacy. Am J Psychiatry. 1994;151:1172–80.

19. Hauri PJ. Can we mix behavioral therapy with hypnotics when treating insomniacs? Sleep. 1997;20:1111–8.

20. Murtagh DR, Greenwood KM. Identifying effective psychological treatments for insomnia: a meta-analysis. J Consult Clin Psychol. 1995;63:79–89.

Each year, members of two different medical faculties develop articles for “Practical Therapeutics.” This article is one in a series coordinated by the Department of Family Medicine at Wright State University School of Medicine, Dayton, Ohio. Guest editors of the series are Cynthia G. Olsen, M.D., and Gordon S. Walbroehl, M.D.



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