SAN DIEGO— Chronic insomnia has been associated with impaired cognitive function, poor general health, and increased incidence of psychiatric disorders, and patients with chronic insomnia frequently suffer in silence, according to Sonia Ancoli-Israel, PhD, who spoke about sleep disorders at the 17th Annual Meeting of the American Neuropsychiatric Association.

DIAGNOSING INSOMNIA

The DSM-IV diagnostic criteria for primary insomnia are difficulty falling asleep, difficulty staying asleep, or nonrestorative sleep. "Not getting enough sleep at night is not sufficient. For a diagnosis of insomnia, there must be some sort of daytime impairment," said Dr. Ancoli-Israel, who is a Professor of Psychiatry at the University of California, San Diego.

The prevalence of insomnia increases with age. Surveys suggest that 10% to 20% of the general adult population complain of difficulty sleeping every night or at least three nights a week. In elderly populations, the prevalence increases to approximately 50%. "However, it is important to note that in older adults, insomnia is most prevalent among those who have a medical or psychiatric problem; so aging is not the cause. Rather, the cause is often a medical or psychiatric problem that goes along with aging and the medications we use to treat those problems," she said.

Insomnia can be difficult to identify because most patients don’t report sleep problems to their physicians, Dr. Ancoli-Israel continued. In fact, a survey conducted by the National Sleep Foundation found that only 5% of people who had chronic insomnia told their physicians about it, and 26% happened to mention it if they were visiting a physician for another reason. The survey found that 69% never discussed the problem with their doctor. "This means that physicians need to ask their patients about sleep to make a diagnosis of chronic insomnia," she added.

CAUSES OF INSOMNIA

Before developing a treatment plan, physicians need to understand why a patient is having difficulty sleeping. Common causes include:

• Psychiatric conditions, such as anxiety and depression.

• Medical conditions, such as chronic lung disease, heart failure, pain disorders.

• Acute stressors, such as bereavement, relocation, marriage/divorce.

• Circadian rhythm disorders, such as advanced/delayed sleep phase, irregular sleep/wake schedule.

• Medications, such as ß-blockers, bronchodilators, corticosteroids, decongestants.

• Primary sleep disorders, such as sleep apnea.

• Poor sleep hygiene practices, such as alcohol, caffeine, or nicotine use.

According to Dr. Ancoli-Israel, difficulty sleeping puts people at greater risk for psychiatric disorders. In a study comparing patients with resolved versus unresolved insomnia one year after the initial diagnosis of insomnia, investigators found that people whose insomnia was not successfully treated were at much greater risk for any psychiatric disorder, and specifically for depression and anxiety disorders, she said.

TREATING INSOMNIA

Insomnia treatment goals are to improve the patient’s presenting symptoms (ie, difficulty falling or staying asleep, nonrestorative sleep), quality of life, and functionality—and to reduce the burden of insomnia on comorbid conditions. Once a physician diagnoses a patient with insomnia, he or she needs to educate the patient about good sleep practices, including:

• Establishing a standardized wake-up time.

• Limiting the amount of time spent in bed, especially time not spent asleep.

• Limiting napping, unless the patient is a shift worker.

• Avoiding exercise right before bedtime.

• Avoiding looking at the clock after going to bed.

• Reducing or eliminating nicotine, caffeine, and alcohol intake.

Before initiating treatment, Dr. Ancoli-Israel recommends asking the patient to keep a sleep log for at least two weeks. "This is a good way for both the patient and the physician to find out about the patient’s sleep. Patients should keep track of their bedtime, time of awakening, time to sleep onset, total sleep time, frequency of awakening, difficulty falling back to sleep, feeling unrested upon wakening, and frequency and types of medications taken. A sleep diary will also be helpful in diagnosing circadian rhythm disorders and evaluating treatment outcomes."

However, to effectively treat their insomnia, patients will need more than just improved sleep hygiene. Other nonpharmacologic therapies include cognitive behavioral therapy, relaxation training, sleep restriction, and stimulus control. "People can change their sleep pattern using bright light," Dr. Ancoli-Israel said. "The timing of the light, as well as the intensity of the light, is crucial. People can use light boxes to get bright light exposure and adjust their circadian pattern."

COMBINATION THERAPY

"We believe that combining cognitive behavioral therapies with pharmacologic therapy is the best approach for treating insomnia. According to the NIH, behavioral and cognitive behavioral therapies have demonstrated efficacy in randomized controlled trials. Cognitive therapy methods include cognitive restructuring, in which anxiety-producing beliefs and erroneous beliefs about sleep and sleep loss are specifically targeted," said Dr. Ancoli-Israel. Cognitive therapy methods have been found to be as effective as prescription medications for the brief treatment of chronic insomnia. In addition, the beneficial effects of cognitive behavioral therapy, in contrast to those produced by medications, may last well beyond the end of treatment.

MELATONIN

The NIH also evaluated the effect of melatonin on sleep. Melatonin is a natural hormone produced by the pineal gland that plays a role in the control of circadian rhythms. Because synthetic melatonin is not regulated by the FDA and because preparations vary in their melatonin content, comparisons across studies are difficult. Although melatonin appears to be effective for the treatment of circadian rhythm disorders, little evidence exists for efficacy in the treatment of insomnia. Additionally, there is no well-defined effective dose. "In short-term use, melatonin is thought to be safe, but there is no information about the safety of long-term use," Dr. Ancoli-Israel said.

PHARMACOTHERAPY

Many medications have been used for the treatment of insomnia. One of the most common classes is the antihistamines, or the H¹ receptor antagonists. According to the NIH, antihistamines are the most commonly used over-the-counter treatments for chronic insomnia. However, there is no systematic evidence for efficacy, and there are significant concerns about the risks of these medications. "Tolerance develops rapidly to the sedative effects. Additionally, there is the potential for residual effects. There is no well-defined effective dose, and the half-life is poorly defined. The adverse effects are not benign, and they include dry mouth, blurred vision, urinary retention, constipation, and risk of increased intraocular pressure in individuals with narrow-angle glaucoma," Dr. Ancoli-Israel reported.

"There is also residual daytime sedation, diminished cognitive function, and delirium, which is a particular concern in the elderly," she said. In one study, hospitalized elderly who were cognitively intact were given 25 to 50 mg of diphenhydramine, and they experienced symptoms of delirium, inattention, disorganized speech, altered consciousness, abnormal psychomotor activity, altered sleep/wake cycle, and behavioral disturbances.

Sedating antidepressants are another pharmacologic choice. These medications are potentially advantageous for patients experiencing chronic insomnia secondary to depression. Disadvantages include inconsistent efficacy and a poor side effect profile, including cardiovascular effects and residual effects; also, there is no well-defined effective dose, Dr. Ancoli-Israel related. "The NIH has concluded that all antidepressants have potentially significant adverse effects, raising concerns about the risk-benefit ratio. Moreover, there is a need to establish and communicate to prescribers dose-response relationships for all of these agents," she said.

Other sedating medications, such as barbiturates and antipsychotics, have been used in the treatment of insomnia, Dr. Ancoli-Israel added. "Studies demonstrating the usefulness of these medications for either short- or long-term management of insomnia are lacking. Furthermore, all of these agents have significant risks, and thus their use in the treatment of chronic insomnia cannot be recommended."

Ten sedative hypnotics are currently FDA approved for the treatment of sleep disorders, Dr. Ancoli-Israel continued. Some are long acting and may have carryover effects, such as sedation, drowsiness, performance impairment, and amnesia. In contrast, short-acting agents may have reduced risk for carryover effects. Long-acting hypnotics include flurazepam and quazepam. The half-life ranges from 40 hours to more than 100 hours. "These are rarely used anymore for the treatment of insomnia," she noted. Intermediate-acting hypnotics are estazolam, temazepam, and eszopiclone. Their half-life ranges from four to 24 hours. The short-acting hypnotics are triazolam, zolpidem, zolpidem ER, zaleplon, and ramelteon. Their half-life ranges from one to five hours.

"In summary, over-the-counter sleep agents lack safety and efficacy data supporting their use in chronic insomnia. Few data support use of sedating antidepressants in insomnia not associated with depression, and their side effect profile is worse than that of indicated agents. Short-, intermediate-, and long-acting benzodiazepines are efficacious, but their safety and adverse event profiles are worse than those of newer agents. Short-acting nonbenzodiazepine hypnotics are effective in initiating sleep and/or maintaining sleep and have a superior safety/adverse event profile to that of older agents. Melatonin agonists have a new mechanism of action and appear to be effective, but clinical experience is too limited to compare their safety profile to other hypnotics," she said.

—Michelle Stephenson

Suggested Reading
Ancoli-Israel S, Ayalon L. Diagnosis and treatment of sleep disorders in older adults. Am J Geriatr Psychiatry. 2006;14:95-103.
Basu R, Dodge H, Stoehr GP, Ganguli M. Sedative-hypnotic use of diphenhydramine in a rural, older adult, community-based cohort: effects on cognition. Am J Geriatr Psychiatry. 2003;11:205-213.
Morin CM, Leblanc M, Daley M, et al. Epidemiology of insomnia: prevalence, self-help treatments, consultations, and determinants of help-seeking behaviors. Sleep Med. 2006;7:123-130.

Return to table of contents