Diagnosing Sleep Disorders - Physician Information

The effects of inadequate sleep are a growing concern for physicians, researchers, and patients.

This Web page has been prepared by Sleep HealthCenters^® to provide you and your staff with practical information about the diagnosis and treatment of sleep disorders.

When a sleep disorder is suspected, specialized clinical evaluation and possibly sleep monitoring may be of great value to you and your patients.

It is recommended that the physician provide all patients who consider entering a sleep monitoring program with a copy of the patient brochure, Sleep HealthCenters: Can we help you get a good night's sleep? Patient brochures are available from Sleep HealthCenters^® at no charge. Printed copies of this physician information is also available. To obtain printed copies of either of these pieces, please contact Sleep HealthCenters^® at 1-877-753-3742 or 617-527-2227.

• Introduction
• Symptoms of Sleep Disorders 
• Types of Sleep Disorders                   
  • Chronic Insomnia                            
    • Conditioned Insomnia                       
    • Poor Sleep Hygiene
    • Mood/Anxiety Disorders 
    • Restless Legs Syndrome/Periodic Limb Movement Disorder
    • Medical Disorders
    • Circadian Rhythm Disorders
    • Medications
  • Hypersomnia
    • Sleep Apnea/Upper Airway Resistance Syndrome        
    • Narcolepsy
• Summary
• Bibliography
• Appendices
  • A: Ten Practical Tips for Good Sleep "Hygiene"
  • B: Sleep Apnea Screening Tool 
    

Introduction

There is abundant evidence that inadequate sleep, whether acute or chronic, can adversely impact the quality of life of the afflicted individual. These sequelae generally include diminished cognitive ability, reduced physical performance, and mood instability. The level of the impairment relates quantitatively to the severity of the sleep deprivation. Therefore, good quality sleep is an important component of optimal health and performance. In addition, there is evolving evidence that certain sleep disorders may negatively impact physical health as well. As a result, in optimally caring for patients, physicians need to recognize sleep disorders and provide timely treatment for patients afflicted by these disorders.

It is currently estimated that over 30 million Americans suffer from a chronic sleep disorder with an even greater number having episodic or transient problems. Two to four percent of adults suffer from symptomatic sleep apnea while five to ten percent of the population have chronic insomnia. Other sleep disorders (narcolepsy, periodic limb movement disorder, etc.) are less common, but substantially impact the well-being of these patients. However, only a small minority of these individuals have been identified and treated.

As the currently available modalities to diagnose and treat sleep disorders steadily improve and the public becomes increasingly focused on healthy life-styles and appropriate care of these diseases, physicians will be expected to have a working knowledge of healthy sleep practices and the standard approaches to the management of sleep disorders. This brochure provides an overview of the principal sleep disorders and the basics of sleep hygiene. However, if more detailed information is needed, it can be obtained by contacting Sleep HealthCenters.

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Symptoms of Sleep Disorders

Patients experiencing a sleep disorder often complain of one or more of the following symptoms:

• inability to stay awake during the day
• inability to fall asleep or stay asleep at night
• sleepiness at inappropriate times during the day
• prominent snoring
• gasping or choking during sleep
• restless, uncomfortable legs in the evening or at night
• unusual events occurring during sleep
  • walking
  • talking
  • nightmares

The information that follows is intended to provide you with a brief overview of several of the most common sleep disorders, their causes, diagnostic approaches, and treatment options. To find out more about sleep disorders or to contact a sleep specialist in your area, call 1--877-SleepHC (1-877-753-3742), or contact Sleep HealthCenters via  e-mail at info@sleephealth.com.

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Chronic Insomnia

At least sometime during the previous year, one in three adults has had trouble falling or staying asleep during the night, or waking up too early in the morning. This condition, known as insomnia, affects people of all ages and may lead to irritability, excessive daytime sleepiness, unrefreshing sleep, or depression.

Acute insomnia that lasts for a few days or weeks is often caused by stress or excitement and is usually self-limiting. However, if it is debilitating, it can be successfully treated with hypnotics. Importantly, without resolution of the acute insomnia or without proper treatment, it can become conditioned insomnia, a chronic disorder.

Chronic insomnia, that which lasts for months or years, is typically a symptom of an underlying disorder. What follows is a brief description of the most common underlying causes of insomnia and therapies recommended for treatment.

Conditioned Insomnia

Conditioned insomnia can begin with any acute insomnia, but persists and worsens because the patient starts to feel apprehensive about falling asleep. Most patients can return to normal sleep patterns after implementing good sleep habits and/or relaxation techniques. (See Appendix A) In some cases, hypnotics are needed for a short period of time to reduce anxiety and reestablish confidence.

Poor Sleep Hygiene

While many sleep disorders are related to a physical, psychological, or biological condition, some are merely the result of poor sleep hygiene, which refers to a variety of behaviors that can influence the quality or quantity of sleep. Improving such poor hygiene can be accomplished by integrating simple behavior modification techniques into the patient's daily routine. Such techniques may include making the bedroom a "restful" environment, sticking to a regular sleep schedule, using relaxation techniques, getting more exercise, and eliminating the use of stimulants prior to bed. (See Appendix A)

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Mood/Anxiety Disorders

Up to half of all chronic insomnias are caused by depression, anxiety disorders, bipolar disorder, or chronic psychoses. Appropriate treatment of these psychiatric disorders generally leads to improved sleep. Persistent sleep problems after psychiatric treatment may indicate the presence of another underlying cause of insomnia; in particular, many of the new antidepressants may produce insomnia.

Restless Legs Syndrome (RLS) and Periodic Limb Movement Disorder (PLMD)

Restless Legs Syndrome (RLS)

Restless Legs Syndrome (RLS) is a sensory-motor disorder affecting five to ten percent of the population that can produce difficulty falling asleep or returning to sleep after an awakening. The symptoms are a "crawly," "achy," or painful sensation, usually in the lower legs (or less commonly in the arms), and a need to move (restlessness) that may temporarily relieve the sensory symptoms. At times, involuntary twitches or "jumps" of the limb may occur. Once this disorder begins, it often continues to progress with advancing age.

Heredity accounts for about thirty percent of cases. The remaining seventy percent of cases have no identifiable cause, although neuropathy, renal failure, alcohol or caffeine use, iron deficiency, or certain medications may contribute to the problem.

If the underlying causes of RLS cannot be determined, first-line treatment is with low doses of dopaminergic agents (e.g., L-Dopa). Other options include benzodiazepines, opiates, and anticonvulsants.

Periodic Limb Movement Disorder (PLMD)

Like RLS, Periodic Limb Movement Disorder (PLMD), also known as nocturnal myoclonus, is a movement disorder that disturbs sleep. Unlike RLS, PLMD involves involuntary movements that occur when the person is sleeping. Patients with RLS usually have PLMD, but most people with PLMD do not have RLS. Restlessness and nonrestorative sleep may be the only recognized symptoms in a patient with PLMD.

The treatment of PLMD is similar to that of RLS.

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Medical Disorders

Several medical illnesses have been shown to cause or contribute to insomnia. These include: cardiac disorders such as nocturnal angina or paroxysmal nocturnal dyspnea; pulmonary dysfunction such as COPD and chronic bronchitis; gastrointestinal difficulties such as nocturnal reflux; urinary problems such as nocturia and renal failure; musculoskeletal pain caused by rheumatoid arthritis, osteoarthritis, or fibromyalgia; endocrine malfunction, most commonly hypothyroidism, hyperthyroidism, and diabetes; and neurologic disorders such as dementia, Parkinson's, stroke, and migraine.

Careful consideration of how these disorders influence sleep and how to modify their impact is an important aspect of sleep disorders medicine.

Circadian Rhythm Disorders

As the name implies, these disorders are associated with disruption in a person's circadian rhythm. They affect people in one of two ways and are therefore divided into two categories, Delayed Sleep Phase Syndrome (DSPS) and Advanced Sleep Phase Syndrome (ASPS). In both cases, light therapy and possibly melatonin can be used to reset the biological clock.

Delayed Sleep Phase Syndrome

This form is most frequently characterized by difficulty falling asleep until quite late and by trouble waking up at conventional times, and is most often seen in adolescents and young adults.

Advanced Sleep Phase Syndrome

This form most often affects the elderly and is characterized by falling asleep too early in the evening and awakening too early in the morning.

Medications

Multiple prescription medications may produce or aggravate insomnia. Some antidepressants, corticosteroids, antihypertensives, decongestants, or bronchodilators require particular consideration in a patient with insomnia.

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Hypersomnia (Excessive Daytime Sleepiness)

Excessive daytime sleepiness can be the result of inadequate sleep quality or quantity, medications, or a dysfunction within the part of the central nervous system responsible for sleep-wake patterns. What follows is a description of several of the more common causes of hypersomnia.

Sleep ApnealUpper Airway Resistance Syndrome

Sleep apnea syndrome is a potentially serious condition characterized by the repetitive cessation or reduction of airflow during sleep. There are two types of sleep apnea: obstructive sleep apnea (OSA) and central sleep apnea (CSA), and a related disorder known as Upper Airway Resistance Syndrome (UARS).

Obstructive Sleep Apnea (OSA)

The more common of the two, OSA, is a disorder characterized by repetitive collapse of the pharyngeal airway during sleep. It is caused by abnormalities in the anatomy and muscle control of the airway. The recurrent obstruction causes loud snoring, hypoxemia, brief awakenings, and a rise in blood pressure. Typically, these apneas occur hundreds of times every night. Chronic sleep apnea is associated with hypertension, excessive daytime sleepiness, and, possibly, increased mortality. This condition affects four percent of men and two percent of women, with middle-age, overweight men making up the majority of cases. OSA may also run in families.

A questionnaire has been developed to help clinicians determine the probability of sleep apnea in a specific patient. A copy of this questionnaire appears in Appendix B of this document.

Upper Airway Resistance Syndrome (UARS)

Patients with UARS present with many of the same symptoms as OSA patients (excessive daytime drowsiness, disrupted nocturnal sleep, and snoring), but they lack the frank apneas or hypopneas that are characteristic of OSA. UARS has no clearcut diagnostic criteria, making it one of the most underdiagnosed sleep disorders. Fortunately, the sophisticated recording techniques now used in sleep evaluations can help in making this diagnosis.

Treatment for both of these obstructive upper airway disorders varies by patient and severity of symptoms. Current therapies include weight loss for the obese, Continuous Positive Airway Pressure (CPAP) to prevent pharyngeal collapse, dental appliances that advance the tongue or jaw to open the airway, or surgery that removes excessive tissue from the upper airway.

Central Sleep Apnea (CSA)

CSA occurs when the respiratory center in the brain repetitively fails to initiate a breath. As oxygen levels fall, the sleeper often awakes gasping for breath as his/her body struggles to adjust its oxygen and carbon dioxide levels. Underlying causes include abnormalities or extremes of normality in the ventilatory control system and heart failure.

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Narcolepsy

Patients with narcolepsy experience excessive daytime sleepiness and may fall asleep at inappropriate times. Other symptoms include: cataplexy (a sudden loss of muscle control associated with strong emotions), disturbed nocturnal sleep, sleep paralysis, and hypnogogic hallucinations (in the sleep/wake transition).

Researchers have demonstrated a link between narcolepsy and certain genes. However, genetic testing is not often required as clinical findings from an overnight sleep study and a Multiple Sleep Latency Test (MSLT) generally provide adequate information for diagnosis.

While there is no cure for narcolepsy, prescription stimulants and scheduled daytime naps improve daytime wakefulness, while a REMsuppressant can abolish cataplexy.

Although the prevalence of narcolepsy is considered to be low, it is twice that of multiple sclerosis. While the symptoms of narcolepsy tend to appear during adolescence, the disorder is most commonly diagnosed during the patient's 30s or 40s.

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Summary

Patients with insomnia and hypersomnia often need careful evalua­tion to determine the underlying cause of their sleep disturbance. The varied symptoms of sleep disorders often result in these patients presenting in a complicated manner that leads to confusion as to their underlying diagnosis. Multiple underlying causes for sleep disruption may be present; each of which requires treatment to produce good quality sleep. Sleep medicine specialists using state­of-the-art diagnostic techniques as well as clinical experience with sleep disorder patients can often provide a thorough and accurate diagnosis plus effective treatment.

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Bibliography

Broughton RJ. Chapter on Narcolepsy. Handbook of Sleep Disorders. Edited by Michael J. Thorpy. Published by Marcel Dekker, Inc. NY; 1990:197-216.

Dijk, Derk-Jan. Internal rhythms in humans. Seminars in Cell and Developmental Biology 1996; 7:831-836.

Dyken ME, et al. Investigating the relationship between stroke and obstructive sleep apnea. Stroke 1996. American Heart Association Inc. March 1996; 27:401-407.

Earley CJ, Allen RP. Pergolide and carbidopal levodapa treatment of the restless legs syndrome and periodic leg movements in sleep in a consecutive series of patients. Sleep 1996; 19:801-810.

Ford DE, Kamerow DB. Epidemiologic study of sleep disturbances and psychiatric disorders. JAMA 1989; 262:1479­1484.

Freedman DX, et al. Consensus conference, drugs and insomnia: the use of medications to produce sleep. JAMA 1984; 251(18): 24102414.

Hla KM, et al. Sleep apnea and hypertension: a population-based study. Ann Intern Med 1994; 120:383-388.

Ondo W, Jankovie J. Restless legs syndrome: clinicoeriologic correlates. Neurology 1996; 47:1435-1441.

Report of the National Commission on Sleep Disorders Research. National Institute of Health. 1993.

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; 20:908-915.

Strollo PJ Jr. and Rogers RM. Obstructive sleep apnea. New Eng J Med 1996; 334.

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Appendix A

Ten Practical Tips for Good Sleep 'Hygiene" Developed by: John Winkelman, M.D., Ph.D., Boston, MA

1.      If you do not fall asleep within 20 minutes, get out of bed and do something relaxing and distracting. For many people, this is reading.

2.      Avoid housework, bills, work, or anything that is too stimulating within 2 hours of bedtime or during a nighttime awakening.

3.      Although some people's insomnia is helped by a midday nap, for most, napping will interfere with falling asleep at night.

4.      Avoid alcohol within 5 hours of bedtime. Alcohol is a poor hypnotic and causes nighttime awakenings.

5.      Avoid caffeine (tea, coffee, chocolate, soda) after noon. It can cause shallow sleep or nighttime awakenings.

6.      Make your bedroom quiet, safe, and relaxing. Face clocks away from the bed or remove completely to avoid "counting down" the minutes until morning.

7.      Keep consistent bedtimes and wake times 7 days a week.

8.      Schedule "worry time" earlier in the day. Use this time to resolve problems prior to bedtime.

9.      Daily exercise improves insomnia, although the effects may not be immediate. Do not exercise within 4 hours of bedtime.

10.   Avoid going to bed on either an empty stomach or a full stomach. A light snack may be of value.

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Appendix B