Quick viewing(Text Mode)

Sleep Disorders

Sleep Disorders

CHAPTER 2

Sleep Disorders

CHAPTER OUTLINE excessive daytime maintenance of sleepiness (EDS) test (MWT) History of Disorders Index (AHI) Classifi cation of Sleep Disorders Respiratory Disturbance Insomnias Index (RDI) sleep Sleep-Related Breathing Disorders respiratory effort–related hypnagogic Central Disorders of Hypersomnolence arousal (RERA) narcolepsy tetrad Sleep–Wake Disorders upper airway resistance (UARS) Sleep-Related Movement Disorders sudden infant death narcolepsy type i Other Sleep Disorders syndrome (SIDS) hypnagogic Chapter Summary central (CSA) central apnea REM periods LEARNING OBJECTIVES (SOREMPs) Cheyne-Stokes breathing narcolepsy type ii 1. Discuss a brief history of sleep disorders high-altitude periodic idiopathic 2. Learn the classifi cation of sleep disorders as outlined by the breathing recurrent hypersomnia AASM primary sleep apnea of periodic hypersomnolence 3. Describe the features and symptoms of each disorder infancy kleine-levin syndrome 4. Discuss the social and personal impact of specifi c disorders treatment-emergent central hypersomnia sleep apnea insuffi cient sleep syndrome KEY TERMS complex sleep apnea circadian rhythm sleep– obesity hypoventilation wake disorders pickwickian syndrome behavioral of syndrome delayed sleep–wake phase Association of Sleep childhood congenital central alveolar disorder Disorders Centers (ASDC) adjustment insomnia hypoventilation syndrome advanced sleep–wake phase International Classi cation of group therapy late-onset central disorder Sleep Disorders (ICSD) hypoventilation with irregular sleep–wake rhythm insomnia sleep restriction hypothalamic dysfunction disorder psychophysiological self-control techniques alveolar hypoventilation free-running circadian insomnia idiopathic central alveolar rhythm idiopathic insomnia sleep-related breathing hypoventilation non-24-hour sleep–wake sleep state misperception disorders primary rhythm disorder paradoxical insomnia snoring disorder sleep diary (OSA) sleep-related groaning disorder sleep log obstructive apnea hypopnea central disorders of confusional arousal limit-setting disorder oxygen desaturation hypersomnolence EEG arousal multiple sleep latency test sleep terror (MSLT) 12

9781284030273_CH02_Pass3.indd 12 03/04/14 2:19 PM Classifi cation of Sleep Disorders 13

sleep-related periodic limb movements in professional sleep societies had developed, including disorder sleep (PLMS) REM-related parasomnias pLM index the ASDC, Clinical Sleep Society (CSS), Association of REM sleep behavior sleep-related leg cramps Professional Sleep Societies (APSS), American Board of disorder (RBD) (ABSM), and National Sleep Foundation isomorphism sleep-related bruxism (NSF).  e American Academy of Sleep Medicine was body rocking known as the Clinical Sleep Society from 1984 to 1986 recurrent isolated sleep head banging paralysis sleep-related rhythmic and the American Sleep Disorders Association from 1987 to 1998; in 1999 it became the American Academy posttraumatic benign sleep of of Sleep Medicine. disorder (PTSD) infancy In 1990, the AASM developed the fi rst edition of the exploding head myoclonus International Classifi cation of Sleep Disorders (ICSD), syndrome propriospinal myoclonus at sleep-related hallucinations sleep onset (PSM) which categorized and described all known sleep dis- nocturnal excessive fragmentary orders. A second edition of the ICSD was published in bedwetting myoclonus 2005, and the third edition was published in 2014.  e sleep enuresis hypnagogic foot (HFT) information in this chapter is refl ective of the updated sleep talking alternating leg muscle defi nitions and classifi cations of sleep disorders found in sleep-related movement activation (ALMA) disorders sleep starts the ICSD-3. (RLS) hypnic jerks periodic limb movement environmental sleep Classifi cation of Sleep Disorders disorder (PLMD) disorder  e following pages categorize sleep disorders as 1 History of Sleep Disorders outlined in the third edition of the ICSD : 1. Insomnia Since the beginning of time, humans have been fas- a. Chronic insomnia disorder cinated with sleep. Many early writings discuss sleep b. Short-term insomnia disorder and sleep disorders in a variety of ways. In 1836, c. Other insomnia disorder published a series of papers called the d. Isolated symptoms and normal variants “Posthumous Papers of the Pickwick Club.” In these writ- ings, he describes a boy named Joe who was overweight 2. Sleep-related breathing disorders and very tired, and who snored heavily. A drawing of the a. Obstructive sleep apnea disorders boy shows an obese young man with a short, fat neck. i. Obstructive sleep apnea, adult From this, the term Pickwickian syndrome was coined; ii. Obstructive sleep apnea, pediatric although it is not used today, it is similar to a sleep disor- b. syndrome der called obesity hypoventilation syndrome (OHS). i. Central sleep apnea with Cheyne-Stokes Pioneering sleep researchers in the 1950s and 1960s, breathing such as Nathaniel Kleitman, William Dement, and oth- ii. Central sleep apnea due to a medical dis- ers, identifi ed diff erent stages of sleep and were able to order without Cheyne-Stokes breathing recognize specifi c patterns of these stages throughout iii. Central sleep apnea due to high altitude the night.  is, along with the development of new tech- periodic breathing nologies designed to read and record physiological activ- iv. Central sleep apnea due to or ities, gave way to the development of the fi eld of sleep substance disorders. In 1961, the Sleep Research Society began v. Primary central sleep apnea informally with such sleep pioneers as Doctors William vi. Primary central sleep apnea of infancy Dement, Allan Rechtschaff en, Nathaniel Kleitman, vii. Primary central sleep apnea of prematurity Michel Jouvet, and Eugene Aserinsky. In 1968, Doctors viii. Treatment-emergent central sleep apnea Rechtschaff en and Anthony Kales produced A Manual of Standardized Technology Techniques and Scoring Systems c. Sleep-related hypoventilation disorders for Sleep Stages of Human Subjects, which defi ned scor- i. Obesity hypoventilation syndrome ing techniques for sleep studies for the next 40 years. ii. Congenital central alveolar hypoventila- In 1970, Dement started the fi rst sleep disorders tion syndrome lab, which provided all-night evaluations of patients iii. Late-onset central hypoventilation with with sleep complaints; within fi ve years there were four hypothalamic dysfunction more sleep centers in business. In 1975, the Association iv. Idiopathic central alveolar hypoventilation of Sleep Disorders Centers (ASDC) was developed, v. Sleep-related hypoventilation due to which is now known as the American Academy of Sleep medication or substance Medicine (AASM). Its sleep center accreditation went into vi. Sleep-related hypoventilation due to eff ect two years later, in 1977. By the early 1990s, several medical disorder

9781284030273_CH02_Pass3.indd 13 03/04/14 2:19 PM 14 CHAPTER 2 Sleep Disorders

d. Sleep-related hypoxemia disorder h. Sleep-related movement disorder due to e. Isolated symptoms and normal variants medical disorder i. Snoring i. Sleep-related movement disorder due to ii. Catathrenia medication or substance j. Sleep-related movement disorder, unspecifi ed 3. Central disorders of hypersomnolence a. Narcolepsy type I b. Narcolepsy type II Insomnias c. Insomnia can be defi ned as a complaint of a lack of sleep or d. Kleine-Levin syndrome of nonrestorative sleep.  e ICSD-3 defi nes insomnia as “a e. Hypersomnia due to a medical disorder repeated diffi culty with sleep initiation, duration, consoli- f. Hypersomnia due to a medication or dation, or quality that occurs despite adequate opportunity substance and circumstances for sleep, and results in some form of g. Hypersomnia associated with a psychiatric daytime impairment."  e ICSD-2 identifi ed several dif- disorder ferent types of insomnia.  e ICSD-3 consolidates these h. Insuffi cient sleep syndrome types and groups them into the categories of chronic and 4. Circadian rhythm sleep–wake disorders short-term insomnia. Within the chronic insomnia group- a. Delayed sleep–wake phase disorder ing, several characteristic types of insomnia are defi ned. b. Advanced sleep–wake phase disorder c. Irregular sleep–wake rhythm Psychophysiological Insomnia d. Non-24-hour sleep–wake rhythm disorder Psychophysiological insomnia is very prevalent.  e e. Shift work disorder insomnia must last at least one month to classify as f. Jet lag disorder psychophysiological insomnia, and is not caused by an g. Circadian rhythm sleep–wake disorder not outside stressor. Rather, psychophysiological insomnia is otherwise specifi ed (NOS) caused by a learned response that teaches the subject to 5. Parasomnias not fall asleep when planned.  e subject typically has a. NREM-related parasomnias no diffi culty asleep when sleep is not planned, but i. Disorders of arousal from NREM sleep at the normal and during planned , sleep ii. onset is diffi cult to achieve. iii. Sleepwalking iv. Sleep terrors Idiopathic Insomnia v. Sleep-related Perhaps the most detrimental and debilitating form of insomnia is idiopathic insomnia . Idiopathic insomnia, b. REM-related parasomnias also termed “life-long insomnia,” is fi rst identifi ed at i. REM sleep behavior disorder infancy or early childhood and persists throughout the ii. Recurrent isolated sleep paralysis patient’s life.  ere appears to be no external cause for iii. this insomnia, and no other exists that c. Other parasomnias could be a contributing factor. i. ii. Sleep-related hallucinations Paradoxical Insomnia iii. Sleep enuresis Formerly termed sleep state misperception , paradoxical iv. Parasomnia due to medical disorder insomnia consists of the subject’s complaint of insomnia v. Parasomnia due to medication or without any actual evidence of insomnia. Many times in substance the sleep lab, a patient will present poststudy complaints vi. Parasomnia, unspecifi ed of being awake all night, even though the technician d. Isolated symptoms and normal variants was able to determine by viewing the electroencepha- i. Sleep talking lograms (EEGs) that sleep was achieved. In some cases, 6. Sleep-related movement disorders the patient may have had a normal sleep effi ciency, but a. Restless legs syndrome still insists he or she did not sleep at all.  is type of b. Periodic limb movement disorder comment should always be included in the technician’s c. Sleep-related leg cramps notes, because the patient may have paradoxical insom- d. Sleep-related bruxism nia. A useful tool for both the clinician and patient when e. Sleep-related rhythmic movement disorder facing paradoxical insomnia is a sleep diary. A sleep f. Benign sleep myoclonus of infancy diary or sleep log is a self-report of sleep habits over a g. Propriospinal myoclonus at sleep onset period of time. Sleep diaries usually last at least fi ve days,

9781284030273_CH02_Pass3.indd 14 03/04/14 2:19 PM Insomnias 15

and sometimes as long as a month. Figure 2– 1 shows a ■ Get up at the same time every day. sample sleep diary. ■ Go to only when tired. A sleep diary can help the patient see abnormalities ■ Establish relaxing presleep rituals. in their own sleep habits, such as irregular or inconsis- ■ Eat a healthy diet. tent bedtimes, or daytime naps that may aff ect the sleep ■ Exercise regularly. schedule at night. Clinicians can use a patient’s sleep ■ Do not exercise heavily within four hours of diary to point out some of these inconsistencies or poor bedtime. sleep habits.  ey can also use a patient’s sleep diary ■ Maintain a regular schedule. during recorded sleep from a to identify the ■ Avoid caff eine for six hours before bedtime. patient’s misperception of sleep. ■ Avoid drinking . ■ Avoid smoking. Inadequate Sleep Hygiene ■ If you must , do it at the same time every day. ■  e term sleep hygiene refers to habits that are healthy Use sleeping pills conservatively and with a physi- for one’s sleep.  erefore, inadequate sleep hygiene is a cian’s advice. ■ Avoid unnecessary stress when possible. set of habits or practices that are bad for a person’s sleep, ■ Use the bed for sleep rather than watching televi- or may cause a person to sleep poorly. Sleep hygiene sion, reading, planning, or studying. techniques are practices that everyone should follow to ■ Make the a clean, comfortable, relaxing help them fall asleep easier and stay asleep longer. Often environment. a clinician fi nds that a person’s insomnia may be due to ■ Block out light and noise as much as possible from bad habits, in which case the use of these and other sleep the bedroom. hygiene techniques may be taught:

Day Date Time in Time Out Total Time Time Awake Total Sleep Estimated Notes Bed of Bed in Bed Asleep Time Time Sleep Efficiency 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Time in Bed: The final time of day the subject got in bed to go to sleep. Time Out of Bed: The time of day the subject got out of bed for the last time in the morning. Total Time in Bed: The total time in minutes the subject spent in bed during the night. This equals the Time Out of Bed minus the Time in Bed. Time Asleep: The estimated time of day the subject fell asleep for the first time. Awake Time: The estimated time of day the subject awoke for the last time in the morning. Total Sleep Time (TST): The estimated total amount of time the subject actually slept. Estimated Sleep Efficiency: This is calculated by dividing the TST by the Total Time in Bed. A sleep efficiency >90% is considered normal.

FIGURE 2– 1 Sleep log.

9781284030273_CH02_Pass3.indd 15 03/04/14 2:19 PM 16 CHAPTER 2 Sleep Disorders

Following these habits can greatly improve one’s to a REM rebound.  e use of alcohol, sedatives, and ability to fall asleep and stay asleep. pain can increase the likelihood of sleep disturbances due to obstructive respiratory events.  ese Behavioral Insomnia of Childhood relax the muscles, which can lead to the likelihood Also called limit-setting disorder , behavioral insomnia of obstructions in the upper airway. of childhood is comparable to inadequate sleep hygiene Prescription and illegal drugs alike can cause sleep for children or infants. In addition to the sleep hygiene problems, including insomnia. Medications with insom- practices listed in the previous section, parents should nia as a side eff ect include, but are not limited to, the consider other sleep hygiene practices specifi c for children following: such as not putting toys or other distractions in the crib, ■ Beta blockers allowing the child to fall asleep alone rather than in the ■ parent’s arms, or preventing the infant from becoming ■ Adrenocorticotropic dependent on a bottle to initiate sleep. Although some of ■ Monoamine oxidase inhibitors these actions may be appropriate at some points during ■ Diphenylhydantoin infancy or childhood, they should not be practiced on a ■ Calcium blockers regular basis because the child may develop poor sleep ■ Alpha habits. A normal, healthy bedtime routine for a child is ■ Bronchodilators recommended, such as reading for a short period of time. ■ Stimulating tricyclics ■ Insomnia Due to a ■  yroid hormones As its name implies, this insomnia is caused by a diagnosed ■ Oral contraceptives mental illness, and persists for at least one month. Common ■ Antimetabolites mental illnesses contributing to insomnia include depres- ■ Decongestants sion and disorders. Clinicians are faced with the ■  iazides challenge of determining whether the mental illness is causing the insomnia or if another type of insomnia is Short-Term Insomnia Disorder causing the mental illness. For example, a patient suff ering adjustment insomnia from a chronic insomnia can experience as a Also called , short-term insomnia result of the inability to sleep. Alternately, a person who is disorder is extremely common, especially in today’s busy, depressed will often experience insomnia as a symptom. high-stress culture. Almost everyone experiences diffi - culty initiating or maintaining sleep for a night or two Insomnia Due to Medical Condition at some point in their lives.  is can be due to stress, excitement, anticipation, pain, illness, changes in time A very large number of medical conditions have the zones or altitude, reactions to medications, changes in potential of causing insomnia, either short-term or sleep schedules, light, noise, or many other intrinsic or long-term. Some of the most common and persistent extrinsic factors. Adjustment insomnia is also known as insomnia-causing medical conditions include those acute insomnia, and was formerly known as transient associated with pain or discomfort.  ese are more insomnia or short-term insomnia. Adjustment insom- common in the elderly, but can, of course, occur at any age. nia is insomnia associated with a specifi c stressor.  ese Insomnia Due to or Substance stressors can be events in our everyday lives such as stress from work, fi nancial hardship, or marital stress.  ey can Another form of insomnia is secondary to substance also be atypical events such as the death of a loved one abuse or withdrawal.  ese substances most often or a natural disaster. Although adjustment insomnia is include alcohol, drugs, sedatives, stimulants, extremely common, it also typically corrects itself when and opiates. Most drugs have the ability to alter or create the stressor is corrected. If a college student experiences a disturbance in sleep, in one form or another.  ese adjustment insomnia due to stress from upcoming fi nal disturbances can, of course, vary greatly depending on exams, for example, the insomnia will likely be corrected the type of drug used, and the amount, duration, and when fi nals are over. regularity of its use, as well as individual factors. Alcohol can have many eff ects on sleep, including a reduced Insomnia Treatment Options sleep latency, reduced wakefulness, and reduced rapid eye movement (REM) sleep and increased slow wave Insomnia is often a secondary condition. In these cases, sleep during the fi rst third of the night. During the the insomnia is treated naturally as the primary condi- latter portions of the night, alcohol can increase the tion is resolved. For example, a woman experiencing number of arousals and produce sleep fragmentation. insomnia as a result of her painful will likely be It can also increase the likelihood of due able to sleep better if her pain is reduced by medications.

9781284030273_CH02_Pass3.indd 16 03/04/14 2:19 PM Sleep-Related Breathing Disorders 17

When insomnia is the primary condition, or the primary the decrease in airfl ow is 30–90% in amplitude. Both condition is unknown, the clinician must seek to resolve are often associated with an oxygen desaturation the insomnia independently. Some sleep labs include (a decrease in the amount of hemoglobin saturated by an insomnia clinic.  ese clinics use a variety of tech- oxygen), and are often associated with other events such niques to help patients treat their insomnia including as body jerks, limb movements, snores, or brief (three group therapy , light therapy, sleep hygiene, sleep seconds or longer) shifts in EEG frequency called EEG restriction , self-control techniques , and biofeedback . arousals . Group therapy is useful in that it allows the patient to OSA has long been believed to be a contributor to explore possible underlying psychological causes for the hypertension, heart , , depression, and many insomnia and hear the causes of other people’s insom- other serious complications. It often leads to excessive nias. Light therapy can help adjust the circadian rhythm, daytime sleepiness (EDS), memory loss, lack of concen- to help the patient initiate sleep at the appropriate time. tration, and morning . Biofeedback mechanisms train the patient to control Obesity is believed to be the largest contributor to certain physiological parameters such as muscle tension, OSA. Patients with a large neck circumference and excess skin temperature, and EEG recordings, in order to gain body fat, particularly males between the ages of 30 and control over their insomnia.  ese techniques have been 60, are at a higher risk for OSA. Diagnostic criteria for shown to be eff ective in patients who are especially OSA call for an Apnea Hypopnea Index (AHI) of at least tense or stressed. Self-control techniques are more psy- a total of fi ve and per hour of sleep chological in nature than biofeedback mechanisms, but with complaints of daytime sleepiness as well as gasp- the underlying purpose is the same: to allow the patient ing, choking, or snoring, or a Respiratory Disturbance to gain control over his or her ability to initiate and Index (RDI) of at least 15 in the absence of these com- maintain sleep.  ese are helpful for patients who feel plaints. AHI is calculated by dividing the total apneas that their lives are out of control because of any num- and hypopneas by the total sleep time in hours. RDI is ber of reasons. Sleep restriction is another useful tool for calculated by dividing the total apneas, hypopneas, and treating chronic insomnia, especially for older patients. respiratory effort–related arousals (RERAs) by the total  is is particularly useful for people who tend to stay sleep time in hours. A RERA is an EEG arousal that is in bed for longer and longer periods of time per night. associated with a marked decrease in airfl ow, contin- Many people with chronic insomnia may stay in bed ued respiratory eff ort, and consistent oxygen saturation. for 10 hours per night but only sleep 6 hours. For these Upper airway resistance syndrome (UARS), which is patients, the clinician may decide to treat the insomnia similar to OSA, is characterized by RERAs during sleep by restricting the amount of time the patient is in bed and symptoms similar to those of OSA, but that do not per night.  is is another case in which a sleep diary may meet the diagnostic criteria for OSA. be useful. Figure 2– 2 illustrates an obstructive apnea.  e air- fl ow is absent despite the persistence of respiratory Sleep-Related Breathing Disorders eff ort. With the chest and abdomen expanding and con- tracting, and no airfl ow through the nose or mouth, an Sleep-related breathing disorders are divided into those airway obstruction exists. of central origin and those caused by an obstruction. Figure 2– 3 illustrates a hypopnea, also an obstructive Central breathing disorders are characterized by a lack respiratory event. Like obstructive apneas, the eff ort of respiratory eff ort caused by either a central nervous persists; however, the airfl ow is not completely absent, disorder or a cardiac dysfunction. 2 Obstructive respira- but rather decreased. tory events are caused by an obstruction, usually in the Figure 2– 4 shows an obstructive apnea.  e respiratory upper airway, and often are associated with obesity; large eff ort decreases slightly, but persists despite the cessation tongue, tonsils, or adenoids; or infl amed tissue in the of airfl ow. At the end of the event, the patient jerks the upper airway. right leg as a response. Figure 2– 5 Obstructive Sleep Apnea, Adult  e sample in shows another obstructive apnea with an associated EEG arousal and limb Obstructive sleep apnea (OSA) is one of the most movements. common sleep disorders. Although common and  e sample in Figure 2– 6 shows an obstructive apnea dangerous, it is relatively easily diagnosed and treated. during REM sleep. Notice that the cessation of airfl ow OSA is characterized by the presence of repeated is easier to detect with the pressure cannula than with obstructive apneas and hypopneas . Obstructive apneas the thermister. Figure 2– 7 also shows an obstructive are respiratory events classifi ed by a complete cessation apnea. (defi ned as a decrease in amplitude of at least 90%) of  e epoch in Figure 2– 8 shows a subtle hypopnea. airfl ow for at least 10 seconds, and continued respiratory  e decrease in airfl ow would be very diffi cult to see eff ort. A hypopnea is similar to an apnea, although using just a thermister.

9781284030273_CH02_Pass3.indd 17 03/04/14 2:19 PM 18 CHAPTER 2 Sleep Disorders

Obstructive Apnea

Airflow

Effort

FIGURE 2– 2 An obstructive apnea.

Hypopnea

Airflow

Effort

FIGURE 2– 3 A hypopnea.

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin

ECG Snore L Leg R Leg Cannula Thermister Thorax Abdomen SpO2

Cessation of Airflow Continuation of Effort Associated Limb Movement

FIGURE 2– 4 An obstructive apnea. At the end of the event, the patient jerks the right leg.

9781284030273_CH02_Pass3.indd 18 03/04/14 2:19 PM Sleep-Related Breathing Disorders 19

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 Associated EEG Arousal E1-M2 E2-M2 Chin

ECG Snore Associated Limb Movements L Leg R Leg Cessation of Airflow Cannula Thermister Thorax Abdomen Continuation of Effort SpO2

FIGURE 2– 5 Another obstructive apnea with an associated EEG arousal and limb movements.

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin

ECG Snore L Leg R Leg Cannula Thermister Thorax Abdomen SpO2

Obstructive Apnea

FIGURE 2– 6 An obstructive apnea during REM sleep.

Obstructive Sleep Apnea, Pediatric hypercapnia. Paradoxical respiratory eff ort motion in the Like OSA in adults, pediatric OSA is characterized by rib cage may be present as well. obstructive apneas and hypopneas.  e associated OSA has been shown to be more prevalent in infants events are similar as well, and include snoring, labored and children who are obese, and those with Down’s breathing, morning headaches, oxygen desaturation, and syndrome. Even mild cases of pediatric OSA can have

9781284030273_CH02_Pass3.indd 19 03/04/14 2:19 PM 20 CHAPTER 2 Sleep Disorders

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin ECG Snore L Leg R Leg Cannula Thermister Thorax

Abdomen SpO2

FIGURE 2– 7 An obstructive apnea.

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin ECG Snore L Leg R Leg Hypopnea Cannula Thermister Thorax

Abdomen SpO2

FIGURE 2– 8 A subtle hypopnea.

lasting and severe eff ects. OSA in infants and children can sometimes the most appropriate treatment. Continuous inhibit both physical and mental growth, and is believed positive airway pressure (CPAP) is occasionally pre- to be associated with sudden infant death syndrome scribed, but should be used with careful consideration. (SIDS) , an occurrence in which an infant dies during sleep seemingly without warning. Diagnostic criteria for Central Sleep Apnea pediatric OSA require an average of only one obstructive apnea or hypopnea per hour of sleep. Because one of the Primary central sleep apnea (CSA) is characterized by a main causes of OSA in infants and children is large ton- repeated cessation of airfl ow and a concurrent cessation sils or adenoids, a tonsillectomy and adenoidectomy is of respiratory eff ort. Central apneas are often seen in

9781284030273_CH02_Pass3.indd 20 03/04/14 2:19 PM Sleep-Related Breathing Disorders 21

older patients or in patients on CPAP for the fi rst time these samples that there is very little oxygen desatura- or with a very high CPAP pressure.  is is often caused tion, as is common in central events. Figure 2– 12 by low CO 2 levels in the blood. Normal respiratory eff ort is another example of a central apnea, this comes as a result of hypercapnia, or the presence of a one during REM and lasting at least 20 seconds.

high level of CO2 . To reduce these levels, we exhale the CO2 in our lungs. A patient with a resting PaCO2 level less Central Sleep Apnea with Cheyne-Stokes than 40 mm Hg is likely to have CSA. Diagnostic features Breathing of CSA include an average of at least fi ve central apneas per hour during sleep. Occasional central apneas are also Cheyne-Stokes breathing is similar to central sleep common at sleep onset. Figure 2– 9 illustrates a typical apnea in that the underlying cause is central. However, in central apnea.  e airfl ow ceases at the same time as the Cheyne-Stokes breathing, the volume of breaths shows respiratory eff ort, and resumes as the eff ort resumes. a distinct waning and waxing pattern.  is pattern is  e sample epoch in Figure 2– 10 shows a central typically seen during nonrapid eye movement (NREM) apnea.  e airfl ow drops as a result of the lack of respira- sleep and is corrected during REM. Most patients with tory eff ort. When the patient attempts to breathe at the Cheyne-Stokes breathing are males over the age of 60. end of the apnea, he is able to do so without any diffi culty  e diagnostic criteria for Cheyne-Stokes breathing because there is no obstruction present. pattern require an average of at least 10 central apneas  e sample epoch in Figure 2– 11 shows another per hour of sleep that show a crescendo–decrescendo central apnea, approximately 15 seconds long. Notice in pattern.

Airflow

Effort

FIGURE 2– 9 A typical central apnea.

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin ECG Snore L Leg R Leg Cannula Cessation of Airflow Thermister Thorax Cessation of Effort Abdomen SpO2

FIGURE 2– 10 Another central apnea.

9781284030273_CH02_Pass3.indd 21 03/04/14 2:19 PM 22 CHAPTER 2 Sleep Disorders

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin

ECG Snore L Leg R Leg Cannula Thermister Thorax Abdomen SpO2

Central Apnea…cessation of airflow and respiratory effort

FIGURE 2– 11 A 15-second-long central apnea.

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin

ECG Snore L Leg R Leg Cannula Thermister Thorax Abdomen SpO2

Central Apnea…cessastion of airflow and respiratory effort

FIGURE 2– 12 A central apnea during REM and lasting at least 20 seconds.

Central Sleep Apnea Due to Medical Disorder Central Sleep Apnea Due to High-Altitude Without Cheyne-Stokes Breathing Periodic Breathing Medical conditions such as degenerative brainstem High-altitude periodic breathing disorder is character- lesions have been known to cause central respiratory ized by central apneas and hypopneas occurring during events. In this case, the central respiratory events occur a recent ascent to at least 4,000 meters, or approximately as a secondary disorder. 12,000 feet.  e events occur at least fi ve times per hour

9781284030273_CH02_Pass3.indd 22 03/04/14 2:19 PM Sleep-Related Breathing Disorders 23

of sleep.  e occurrence of central events during an Congenital Central Alveolar Hypoventilation altitude adjustment such as this is considered a normal Syndrome response, and tends to correct itself when the subject Congenital central alveolar hypoventilation syndrome returns to lower altitudes. is characterized by the failure of automatic central control of breathing, and is caused by a genetic mutation Central Sleep Apnea Due to Medication in the PHOX2B gene. Subjects with this disorder experi- or Substance ence hypoventilation during both wake and sleep, with Certain drugs, including methadone and hydrocodone, onset usually at birth. Hypoventilation is typically worse have been known to occasionally cause central respiratory during sleep than during wake. events. In this case, the disorder is secondary in nature. Late-Onset Central Hypoventilation with Primary Central Sleep Apnea of Infancy Hypothalamic Dysfunction  is life-threatening disorder affl icting infants is char- Subjects with late-onset central hypoventilation with acterized by long respiratory events, obstructive or hypothalamic dysfunction are typically healthy until central in nature, lasting at least 20 seconds. Primary approximately age 2, when they develop severe obesity central sleep apnea of infancy is extremely dangerous and central hypoventilation. Diagnostic criteria call for for newborns, and should be diagnosed and treated as an absence of symptoms during the fi rst few years of quickly as possible. life, sleep-related hypoventilation, obesity, and a lack of mutation in the PHOX2B gene. Primary Central Sleep Apnea of Prematurity Central sleep apnea is common in premature infants, and Idiopathic Central Alveolar Hypoventilation sometimes requires ventilator support.  e diagnostic Formerly called alveolar hypoventilation or central alveo- criteria for primary central sleep apnea of prematurity lar hypoventilation, idiopathic central alveolar hypoven- include a conceptional age of less than 37 weeks and tilation is defi ned in the ICSD-3 as “the presence of either recurrent central apneas of at least 20 seconds alveolar ventilation resulting in sleep related hypercapnia in duration or periodic breathing for at least 5% of the and hypoxemia in individuals with presumed normal duration of sleep study monitoring. mechanical properties of the lung and respiratory pump.” Diagnostic criteria for this disorder include the presence Treatment-Emergent Central Sleep Apnea of sleep-related hypoventilation that is not primarily due Treatment-emergent central sleep apnea , often referred to another medical disorder or medication. to as complex sleep apnea, is diagnosed after the patient has been diagnosed with OSA and has had a subsequent Sleep-Related Hypoventilation Due to a Medication or positive airway pressure (PAP) titration. After resolu- Substance tion of obstructive events during the titration, central  is disorder is characterized by hypoventilation during events emerge and persist with at least fi ve central sleep that can be traced to a medication or other sub- events per hour of sleep.  ese patients are often placed stance that is known to inhibit respiration, and is not on bilevel PAP, sometimes with a backup rate to help caused by a medical disorder. resolve the central events.  ere is currently much dis- cussion on the existence and prevalence of complex sleep apnea. Sleep-Related Hypoventilation Due to a Medical Disorder Sleep-Related Hypoventilation Disorders  is disorder is characterized by hypoventilation dur- ing sleep that can be traced to a medical disorder that is Obesity Hypoventilation Syndrome known to inhibit respiration, and is not primarily caused Also referred to as hypercapnic sleep apnea, obesity by a medication or substance. hypoventilation syndrome is characterized by hypoven- tilation occurring during sleep in obese individuals. Isolated Symptoms and Normal Variants  is was formerly called Pickwickian syndrome, but this term is no longer preferred because it is also Snoring occasionally used to describe those who have OSA. Also called primary snoring , snoring is defi ned as

Diagnostic criteria for this disorder include a PaCO2 audible vibrations of the upper airway during respira- greater than 45 mm Hg during sleep, a body mass index tions in sleep. Snoring is caused by a partial obstruction (measured by kg/m2) greater than 30, and the absence of the upper airway, often including nasal obstruction, of a medical disorder or medication that may cause and in isolation may or may not be considered malig- hypoventilation. nant. Snoring can often lead to dry mouth or irritated

9781284030273_CH02_Pass3.indd 23 03/04/14 2:19 PM 24 CHAPTER 2 Sleep Disorders

tissues in the throat and can awaken the snorer or the activities. Often these activities appear to be performed bed partner. In some cases, snoring can be loud enough deliberately. A common example of automatic behavior to be disruptive to sleepers in adjacent rooms. Snoring is speaking on a subject matter that is completely out of tends to increase with body mass, and may or may not context for the situation. be combined with obstructive apneas. Because snoring is EDS is the most common symptom of narcolepsy. often combined with apnea and is a common feature of EDS can manifest itself in many ways, such as diffi culty OSA, it is typically investigated further with a sleep study. concentrating, diffi culty remaining awake during nor- Snoring can often be corrected with CPAP, dental appli- mal waking hours, decreased cognition, napping, ances, or in mild cases a multitude of other devices and hallucinations, memory loss, and decreased performance methods. Many snoring treatments have been developed in work-related tasks. Memory loss and diffi culty concen- in the last few years, including throat lubricants, special- trating as a result of EDS often lead to poor performance ized to further open the airway, dental devices to in school or work (see Figure 2– 13 ). Excessive daytime pull the lower jaw forward, pillar implants inserted into sleepiness can also negatively aff ect one’s personal rela- the soft tissues of the palate, and adhesive strips to widen tionships. Individuals experiencing profound EDS are the nasal cavity.  e eff ectiveness of many of these treat- also at an increased risk for automobile accidents and ments varies greatly according to the severity and other work-related accidents. Nearly half of narcoleptics have characteristics of the patient. reported falling asleep at the wheel. 4 Narcoleptic patients are often able to detect an oncoming sleep attack in time Catathrenia to fi ght it off ; however, narcoleptics are known for falling Sleep-related groaning , or catathrenia , consists of asleep unintentionally and at inappropriate times, such repeated groaning during exhalation, mainly in REM as in the middle of a conversation, while laughing, or dur- sleep. Typically the patient is not aff ected by this disor- ing sexual activity. Even those who fi ght off sleep attacks microsleep . Microsleep is a der, but the bed partner’s sleep is often disrupted as a may experience periods of period of sleep that is so brief the individual may not be result.  is disorder is rare but appears to be more com- aware that he or she slept. Microsleep is often felt as a mon in males than in females. brief lack of or . Brief naps may help narcoleptic patients momentarily with feelings of Central Disorders of EDS and periods of microsleep. Hypersomnolence One of the most well-known and disruptive symp- toms of narcolepsy is cataplexy. Cataplexy comes from  e ICSD-3 refers to this group of sleep disorders as those the Greek words kata , meaning down, and plexis , mean- in which “the primary complaint is daytime sleepiness ing stroke or . Cataplexy is sometimes mistaken not caused by disturbed nocturnal sleep or misaligned for seizure activity, and is characterized by a bilateral loss circadian rhythms.”3 Sleepiness can often be classifi ed of muscle tone, usually provoked by strong . It by questionnaires such as the manifests itself as muscle that can range from or the Stanford Sleepiness Scale, or by tests such as the a mild feeling of weakness to complete limb atonia with a multiple sleep latency test (MSLT) or the maintenance resulting fall. Patients suff ering from cataplexy may drop of wakefulness test (MWT) . items they are holding, which can cause embarrassment Narcolepsy Type I or can be hazardous. Periods of cataplexy usually last only a few seconds, but if prolonged they may lead to a period  e term narcolepsy is derived from the Greek words of REM sleep. Cataplexy is seen in approximately 70% narke, meaning numbness or , and lepsis , mean- ing attack. As the name suggests, narcolepsy is a disorder characterized by sleep attacks. Narcolepsy is primarily caused by a physiological or pathological abnormality. Although the severity and symptoms of narcolepsy may vary greatly between individuals, it is characterized by a variety of symptoms, which may include excessive day- time sleepiness (EDS), cataplexy , and other REM-sleep phenomena such as sleep paralysis and hypnagogic hal- lucinations .  ese four characteristics constitute the nar- colepsy tetrad. Very few narcoleptic patients suff er from all of the listed symptoms, but many suff er from more than one of these. Frequent and often irresistible nap- ping is also a common symptom of narcolepsy. Another common symptom of narcolepsy seen in approximately 20–40% of narcoleptics is automatic behavior , which FIGURE 2– 13 An individual experiencing severe excessive daytime is characterized by the subconscious performance of sleepiness.

9781284030273_CH02_Pass3.indd 24 03/04/14 2:19 PM Central Disorders of Hypersomnolence 25

of narcoleptics, but often these individuals are able to the average sleep latency for normal sleepers usually control the symptoms by controlling emotional stimuli. ranges from 5 to 20 minutes, more than 80% of narco- Narcolepsy type I includes the diagnosis of narcolepsy leptic patients have an average sleep latency of less than with the complaint of cataplexy.  is type was formerly 5 minutes. Sleep onset REM periods (SOREMPs) are also called narcolepsy with cataplexy. indicators of narcolepsy. Two or more SOREMPs during Sleep paralysis, another symptom of narcolepsy, is fi ve MSLT naps and the previous night’s diagnostic sleep characterized by a partial or total paralysis of skeletal study may be indicative of narcolepsy.  e fi nal diagno- muscles that occurs upon awakening or at sleep onset. sis is based on medical history, physical examination, When occurring at sleep onset, this is called hypnagogic ; patient questionnaires, and sleep study results. when it occurs upon awakening it is referred to as As mentioned earlier in this section, there is cur- hypnopompic .  e average REM latency for a normal, rently no known cure for narcolepsy; however, certain healthy adult sleeper is 90–120 minutes; in contrast, behavioral and medical treatments have been shown narcoleptics with sleep paralysis may enter REM sleep to be eff ective in treating the symptoms. A behavioral immediately or almost immediately after sleep onset. treatment that has been shown to be very eff ective Sleep paralysis occurs in about 25% of narcoleptic in narcoleptics is taking short, regularly scheduled patients, and is also often associated with hypnagogic naps during the daytime. Narcoleptics also may fi nd and/or hypnopompic hallucinations, which are seen it helpful to discuss their disorder and its associated in approximately 30% of narcoleptic suff erers.  ese symptoms with friends, family members, and cowork- hallucinations are characterized by vivid, dreamlike ers. Doing so can help relieve some of the embarrass- experiences occurring at sleep onset or upon awakening. ment and stress that may occur with EDS and some of  ey are often accompanied by intense feelings of . the other symptoms of narcolepsy. Perhaps the most Sleep paralysis and hypnagogic and hypnopompic signifi cant behavioral treatment for narcoleptics is hallucinations may also be seen in subjects other than to practice proper sleep hygiene. Sleep hygiene tech- narcoleptics who are severely sleep deprived. Typical niques include practices that are benefi cial to the qual- onset for narcolepsy is during the late teen years or early ity of one’s sleep, and have been shown to be eff ective 20s, and although there is no known cure, there are in improving a patient’s ability to initiate and maintain treatments available that have been shown to be eff ec- sleep and remain awake and alert during the daytime. tive against the symptoms of narcolepsy. Although the Examples of sleep hygiene practices include retiring exact cause of narcolepsy is not known, there appears to and awakening at consistent times from day to day; be a strong genetic component.  ere also appear to be avoiding caff eine, alcohol, and sedatives; getting reg- certain variations in an area on the sixth chromosome ular exercise but avoiding heavy exercise within four called the HLA complex that tend to increase the likeli- hours of retiring; avoiding reading or watching televi- hood of developing narcolepsy. Additional studies of the sion while in bed; and avoiding greasy, fatty foods and brains of narcoleptic patients have found increased levels snacks. Consistently practicing proper sleep hygiene of , , and epinephrine. In some techniques can greatly improve the quality of sleep cases, severe head and brain tumors have been and the quality of life for both narcoleptics and normal known to cause narcolepsy. sleepers. Narcoleptic patients often suff er from depression, In addition to behavioral modifi cations, narcoleptics possibly as a result of the inability to carry out certain may use certain medications to treat the disorder and normal activities, and are often underachievers.  is can its symptoms.  e most common medications used to also lead to low self-esteem. treat narcolepsy are CNS stimulants such as Provigil, Because of the large number of sleep disorders with Ritalin, and Dexedrine. -like stimulants resulting symptoms similar to those of narcolepsy, such as and are diagnosing the disorder may be diffi cult. Physicians also commonly used to treat narcolepsy. CNS stimulants suspecting narcolepsy may have the patient com- are the most commonly prescribed drugs for treating plete certain sleepiness scales or a sleep diary. Most narcoleptics with excessive daytime sleepiness; REM importantly, the physician should order an MSLT pre- suppressants and are often used to ceded by an overnight diagnostic sleep study.  e over- treat narcoleptics with cataplexy, hypnagogic hallucina- night diagnostic sleep study is to rule out the presence tions, and sleep paralysis. In recent years, fl uoxetine and of other sleep disorders such as OSA or periodic limb monoamine oxidase inhibitors have also been shown to movement disorder, which are often the underlying be useful in treating cataplexy.  e diagnostic criteria for causes of certain narcoleptic symptoms.  e MSLT is narcolepsy call for a mean sleep latency of eight minutes performed the following day and consists of a series of or less during an MSLT, at least two sleep onset REM four or fi ve short nap opportunities.  e patient is given periods during the fi ve MSLT naps and the diagnostic the opportunity to fall asleep during these periods, and study from the previous night, and the irresistible need if asleep within 20 minutes, is monitored for the next to sleep or daytime lapses into sleep for at least three 15 minutes. REM periods and early sleep onsets dur- months. Diagnostic criteria for narcolepsy type I also ing these naps can be indicators of narcolepsy. Whereas include cataplexy.

9781284030273_CH02_Pass3.indd 25 03/04/14 2:19 PM 26 CHAPTER 2 Sleep Disorders

Narcolepsy Type II a total sleep time less than expected for the patient’s age Narcolepsy type II is characterized by a diagnosis of for a period of at least three months, and an absence of narcolepsy as defi ned in the ICSD-3, but without the another sleep disorder, medication, or mental or physical presence of cataplexy. An additional diagnostic criterion disorder that may cause the symptoms. Sleep patterns, for narcolepsy type II requires that either cerebrospinal durations, and times are often recorded in a sleep log or fl uid (CSF) hypocretin-1 concentration was not mea- with . Although there are many possible causes sured or that it is measured at > 110 pg/mL. of insuffi cient sleep syndrome, it is common during the teenage years when the need for sleep is high but the sub- Idiopathic Hypersomnia ject’s lifestyle is not conducive to adequate sleep periods. Idiopathic hypersomnia is characterized by EDS, refresh- ing naps, decreased sleep latency (less than eight minutes Circadian Rhythm Sleep–Wake average on an MSLT), an absence of cataplexy, and a sleep Disorders period of a normal duration (6–10 hours). Although these Circadian rhythm sleep–wake disorders are charac- symptoms may be common secondary symptoms in other terized by a disturbance or disruption to the normal disorders, the diagnostic criteria for this disorder require circadian rhythm, which causes the patient to experi- the absence of other sleep disorders causing them. ence excessive daytime sleepiness, insomnia, or both. When the sleep schedule is not a consistent part of the Kleine-Levin Syndrome circadian rhythm, it can greatly disturb the ability to Also referred to as recurrent hypersomnia or periodic initiate or maintain sleep, or the ability to achieve restful, hypersomnolence , Kleine-Levin syndrome occurs when restorative sleep. a patient experiences repeating episodes of hypersomnia (excessive sleeping). Patients may sleep 16–18 hours a Delayed Sleep–Wake Phase Disorder day during these periods, and have associated symptoms Delayed sleep–wake phase disorder is characterized by including hallucinations and .  ese periods of a later sleep time than expected or desired. A patient with hypersomnia may last as long as four weeks, and recur at this disorder is unable to fall asleep at the desired time least once a year. A typical episode lasts approximately or at a time that is considered normal, but is able to at 10 days, with some rare cases lasting several weeks. a later time in the night.  e patient then sleeps until Hypersomnia Due to Medical Disorder late in the morning.  is disorder is common in adoles- cents or young adults who develop habits of staying up  is disorder exists when a primary medical condition is late at night. the underlying cause for hypersomnia. Patients with this diagnosis have the symptoms of hypersomnia, but the Advanced Sleep–Wake Phase Disorder daytime sleepiness occurs as a result of a medical disorder. Advanced sleep–wake phase disorder is character- ized by an earlier sleep time than expected or desired. Hypersomnia Due to Drug or Substance A patient with this disorder has diffi culty staying awake  is disorder is present when the use or abuse of a drug until the normal or expected bedtime, but then awak- or medication is responsible for extended periods of ens early in the morning.  is is common in older adults sleepiness or excessive sleep.  is can occur as a result who develop the lifestyle of eating and sleeping at earlier of drug abuse or prescribed use of certain medications. times than they did at younger ages.

Hypersomnia Associated with a Psychiatric Irregular Sleep–Wake Rhythm Disorder Disorder Irregular sleep–wake rhythm disorder is character- Patients with this disorder meet the diagnostic criteria ized by abnormal sleep and wake times. Although the for hypersomnolence, but the daytime sleepiness is asso- total sleep time during the 24-hour cycle is comparable ciated with a psychiatric disorder.  is is most common with normal sleepers, the sleep periods may come in among those with mood disorders such as depression, the form of several naps as opposed to one main sleep , and seasonal aff ective disorder. period.  e patient also experiences periods of insom- nia and EDS. Insuffi cient Sleep Syndrome Non-24-Hour Sleep–Wake Rhythm Sleep insuf- A very common sleep disorder in today’s busy world, Disorder fi cient sleep syndrome is characterized by not sleeping long enough to satisfy physical and psychological needs. Formerly called free-running disorder , non-24-hour Common alternate names include chronic sleep depriva- sleep–wake rhythm sleep disorder tion and sleep restriction. Diagnostic criteria for insuf- is characterized by a circadian rhythm not consistent fi cient sleep syndrome include daytime lapses into sleep, with the 24-hour .  e patient’s circadian rhythm

9781284030273_CH02_Pass3.indd 26 03/04/14 2:19 PM Parasomnias 27

is often longer than 24 hours, and does not seem to be Sleepwalking related to the light–dark cycle. Many patients with this Sleepwalking is a disorder characterized by certain disorder are blind. behaviors during slow wave sleep such as sitting up in bed, walking, or jumping up and running from the bed. Shift Work Disorder Sleepwalking can range from common behaviors such as Patients with shift work disorder are assigned to work walking calmly through the bedroom or house to violent, a shift that occurs during the late night or early morn- unusual, or dangerous behaviors such as jumping out of ing hours, such as the graveyard shift. As a result of the a second story window. Because of this, sleepwalking has disturbance of the circadian rhythm, the patient typically received much interest over the years. Behaviors such experiences EDS. As a result, many of these workers as sexual activity, texting, or even homicide have been have poor work performance, impaired judgment, and known to occur during sleep. Sleepwalking is common in reduced wakefulness while at work. Much research has children and is considered normal in most prepubescent been done on the topic of shift work and its eff ects on cases. the human body, as more and more people are assigned to work during the normal sleep period. Sleep Terrors Sleep terrors , also known as night terrors , are character- Jet Lag Disorder ized by awakenings from slow wave sleep with feelings of intense fear.  ese events begin with a loud scream or cry Jet lag disorder occurs when a person travels across two and typically involve the patient jumping out of bed and or more time zones, resulting in EDS or insomnia. Other often committing violent acts. Upon going back to sleep symptoms such as gastrointestinal disturbances or poor after a sleep terror, the patient will usually return directly performance often occur. to slow wave sleep and have no recollection of the event in the morning. Circadian Rhythm Sleep Disorder Not Otherwise Specifi ed Sleep-Related Eating Disorder  is disorder is characterized by a disturbance to the Sleep-related eating disorder is characterized by normal circadian rhythm that does not meet the criteria repeated episodes of eating and/or drinking during for other disorders in this class of sleep disorders. Most arousals from sleep.  is often occurs on a nightly basis of these are secondary to medical conditions or medica- or even several times per night, and the patient usually tion or substance use. Examples of medical conditions chooses junk foods that are not typically eaten during associated with this condition include disturbances due the day.  e patient may eat strange combinations of to , Alzheimer’s disease, and movement disor- foods or even dangerous substances. Most patients with ders such as Parkinson’s disease. this disorder are very diffi cult to awaken during these episodes and have no recollection of them in the morn- Parasomnias ing. Patients with this disorder will often gain weight as a result of the high volume of junk foods eaten during parasomnia A is an unwanted physical movement or the night.  ey may also injure themselves while cooking action during sleep. Commonly occurring parasom- during sleep. nias include walking and talking in sleep.  is group of sleep disorders is classifi ed by disorders of arousal from REM-Related Parasomnias NREM sleep, those associated with REM sleep, and other parasomnias. REM Sleep Behavior Disorder (RBD) REM sleep behavior disorder (RBD) consists of physi- Disorders of Arousal from NREM Sleep cal events or activities occurring during REM sleep. In normal sleepers, muscle atonia occurs during REM. Confusional Arousals In patients with RBD, muscle tone is maintained dur- A confusional arousal occurs when a person awakens ing REM sleep, and the muscles may twitch or move. in a confused state.  is usually occurs when awakening Periodic limb movements frequently occur during REM from slow wave sleep during the fi rst third of the night, in patients with RBD. Patients with RBD often - but can occur upon awakening from any stage of sleep. strate isomorphism, or acting out . Upon awaken- Upon awakening, a person with a confusional arousal ing, the patient is likely to remember the he or may be confused about who they are, where they are, and she acted out. Occasionally, the patient may act out vio- what is happening around them.  eir speech may be lently, performing such acts as fl ailing the arms, hitting, slurred and their mental processes slowed. Other sleep kicking, yelling, and so on. Polysomnograms performed disorders such as insomnia or hypersomnia can increase to diagnose RBD typically include arm leads to detect the prevalence of confusional arousals, as can shift work muscle twitches or movements and extra EEG leads to or . rule out seizure activity.

9781284030273_CH02_Pass3.indd 27 03/04/14 2:19 PM 28 CHAPTER 2 Sleep Disorders

Recurrent Isolated Sleep Paralysis this disorder do not respond to bladder sensations by Sleep paralysis, a symptom sometimes associated awakening or restricting the fl ow of .  is is very with narcolepsy, refers to the inability to move at sleep common in children and infants, and is considered nor- onset (hypnagogic) or upon awakening (hypnopom- mal in subjects of this age group. Diagnostic criteria for pic). Periods of sleep paralysis may last a few seconds sleep enuresis require the patient to be at least fi ve years to several minutes. Because sleep paralysis is a common of age and wet the bed at least twice a week. Secondary symptom of narcolepsy, diagnostic criteria for recurrent sleep enuresis can occur in patients with PTSD, those isolated sleep paralysis call for a negative diagnosis of who are victims of abuse, or those who are experiencing narcolepsy. Sleep paralysis is often caused by periods of the enuresis as a result of a medical condition such as sleep deprivation or shifting sleep times or habits. .

Nightmare Disorder Parasomnias Due to Medical Disorder A nightmare is a common occurrence in which a per-  ese disorders are secondary to a medical condition son has an intense, frightening dream that causes an that leads to the parasomnia. Certain neurological disor- awakening. Often upon awakening, the person is still ders such as Parkinson’s disease or dementia can lead to frightened because of the intensity of . sleep-related hallucinations. Nightmares are very common in children and are con- sidered normal for this age group. As a person grows into Parasomnias Due to Medication or Substance , nightmares typically reduce in frequency  ese disorders are secondary to drug or medication use and intensity. Nightmares are common in patients with posttraumatic stress disorder (PTSD) or abuse. Some medications, including tricyclic antide- . A patient with pressants and some treatments for Alzheimer’s disease, PTSD is likely to experience nightmares that relive or can cause RBD. Consuming large amounts of caff eine can cause the patient to re-experience the event(s) that led also lead to RBD. to PTSD. Nightmares occur during REM sleep, which is when most dreaming occurs, and often cause the person Isolated Symptoms and Normal Variants to delay falling back to sleep. Sleep Talking Other Parasomnias Talking during sleep can occur at any age, during any Exploding Head Syndrome stage of sleep, and in people who are otherwise normal and healthy. Sleep talking is often considered benign Exploding head syndrome is a sleep disorder character- unless it disturbs the sleep of the talker or the bed part- ized by an imagined loud noise or sense of explosion in ner, or is associated with other behaviors in sleep. Many the head while falling asleep or awakening. Occasionally, people talk in their sleep without knowing it until they the patient may believe that he or she sees a fl ash of bright begin to share their room with someone else. light. No other physical complaints occur with this disor- der, and there are no malignant physical eff ects to these episodes other than occasional feelings of pain in the head. Sleep-Related Movement Disorders Sleep-related movement disorders are a class of sleep Sleep-Related Hallucinations disorders characterized by simple, often repetitive move- Like sleep paralysis, sleep-related hallucinations are ments during sleep or wake that can disrupt the sleep of common features of narcolepsy. Hypnagogic and the patient, the bed partner, or both. hypnopompic hallucinations often occur in patients with narcolepsy; the patient experiences a visual hallu- Restless Legs Syndrome (RLS) cination either just before sleep onset or at awakening. Restless legs syndrome (RLS) is a disorder charac-  ese hallucinations are often related to sleep onset terized by the irresistible urge to move the body in an REM periods, and may be frightening and vivid enough eff ort to stop uncomfortable or odd sensations, most to cause the patient to jump out of bed and occasion- often in the legs.  ese sensations or feelings are typi- ally injure him- or herself. Diagnostic criteria for sleep- cally described as creeping, crawling, itchy, burning, related hallucinations require the absence of other sleep or tingling feelings.  ese feelings and symptoms tend disorders such as narcolepsy that could be the primary to increase during periods of , such as while cause.  ese episodes occur more frequently in adoles- watching television, reading, or attempting to fall asleep. cents and young adults, and can be a secondary feature Because these feelings usually occur at night while the of Parkinson’s disease or dementia. individual is attempting to fall asleep, restless legs syn- drome often leads to complaints of insomnia. Sleep Enuresis Individuals suff ering from RLS often fi nd themselves Also called or bedwetting , sleep rubbing or slapping their legs, twitching their muscles, enuresis is characterized by repeated episodes of invol- bouncing their feet, jerking their legs, and getting up to untary during sleep. Patients suff ering from walk around the room in order to alleviate the feelings of

9781284030273_CH02_Pass3.indd 28 03/04/14 2:19 PM Sleep-Related Movement Disorders 29

restlessness.  e amount of time required to alleviate the agents have been shown to regulate muscle movements symptoms of RLS can range anywhere from a few min- during sleep. agents have also been eff ec- utes to over an hour. tive in inhibiting the muscle contractions, and GABA Restless legs syndrome onset can occur at any age, also help relax muscle contractions. including infancy. RLS in children is often misdiagnosed On the polysomnogram, periodic limb movements as hyperactivity or growing pains. Most RLS suff erers last 0.5 to 5 seconds. Periodic limb movements occur begin experiencing symptoms by young adulthood and within 5 to 90 seconds of each other, and at least four of continue to experience these symptoms throughout their these movements occur in a series.  e required ampli- lives. RLS aff ects more than 5% of the total population tude of these limb movements is at least 8 μV higher than in the .  e severity and frequency of RLS the resting electromyogram (EMG) amplitude. symptoms tend to vary with stress, pain, illness, or other A PLM index is calculated by dividing the total num- factors.  ey often appear during pregnancy and disap- ber of periodic limb movements by the total sleep time in pear immediately after pregnancy.  e most commonly hours, giving an average number of periodic limb move- associated medical condition with RLS is iron defi ciency. ments per hour of sleep time. PLMD may be diagnosed if Obstructive sleep apnea, Parkinson’s disease, diabetes, the patient has a PLM index greater than 15 per hour, or and rheumatoid arthritis are other medical condi- 5 per hour in children. tions that are commonly seen in RLS patients. Certain  e sample shown in Figure 2– 14 shows a series of medications such as antihistamines, antidepressants, six periodic limb movements on a 300-second epoch. and can worsen the symptoms of RLS.  ey are not associated with respiratory events, and they Medications used to treat RLS often include dopamine occur during NREM sleep. agonists, opioids, , and .  e sample in Figure 2– 15 shows another 300-second Massage and musculoskeletal manipulations have also epoch in which four periodic limb movements occur. In been found to be helpful in some cases. this example, both legs are showing movement. Sleep technicians should watch their patients carefully Finally, in the sample shown in Figure 2– 16 we again for signs of RLS and make note of them for the physician. see limb movements (outlined with dark circles) in a Because patients are often not aware of this disorder, it is 300-second epoch. However, the limb movements in this important for the technician to ask the patient appropri- case are preceded by respiratory events (outlined with ate questions to help the physician determine if RLS is lighter circles on the line below). Because the respiratory present. Many patients with RLS also have periodic limb events appear to be the primary cause of the limb move- movement disorder (PLMD) . ments, these would not be considered part of a PLMD diagnosis. If periodic limb movements persisted after the Periodic Limb Movement Disorder (PLMD) respiratory events were corrected, the patient may then be diagnosed with PLMD. Periodic limb movement disorder, also called periodic limb movements in sleep (PLMS) , and formerly known Sleep-Related Leg Cramps as nocturnal myoclonus, is a common sleep disorder  is disorder is characterized by intense and sudden aff ecting approximately one third of adults over the age muscle cramps in the legs during sleep.  ese muscle of 60 years.  is disorder occurs when the patient invol- cramps are often painful, and result in the patient waking untarily moves the limbs (usually the legs) during sleep, up from sleep, thereby disturbing the sleep period. and other symptoms occur as a result of this movement. Occasional sleep-related leg cramps are very common  ese movements are repetitive and occur in periodic in the elderly, and have been reported only occasionally episodes, and are seen mostly in stage N2.  e symptoms in infants and young children. of PLMD are not usually seen during REM sleep because of the muscle atonia that occurs during REM. Sleep-Related Bruxism  e most common symptoms of periodic limb move- ment disorder include fragmented sleep architecture, Bruxism is grinding the teeth or clenching the jaw daytime sleepiness, and frequent EEG arousals.  ese during sleep.  is parasomnia is usually discovered or symptoms tend to increase with stress and certain medi- initially suspected by the patient’s dentist, who may see cations such as tricyclic antidepressants. Periodic limb evidence of the teeth grinding. Sleep-related bruxism movement disorder not only aff ects the sleep of the indi- can occasionally cause the patient to awaken, but is often vidual suff ering from the disorder, but also can often, and more disruptive to the bed partner.  e patient may in some cases more severely, aff ect the sleep of the bed experience muscle soreness or headaches in the morning, partner who is being kicked during the night. As a result, but more importantly can grind down the enamel of the PLMD patients are often referred to the physician by the teeth. Bruxism is most commonly seen among children spouse or bed partner. and adolescents, who typically grow out of the disorder;  e most common treatments for PLMD include the however, some people experience bruxism their entire use of certain medications. Benzodiazepines, which sup- lives. For many, a dental appliance such as a mouth guard press the muscle contractions, are perhaps the most com- is appropriate and can be eff ective in preventing further monly prescribed medications for PLMD. damage to the teeth.

9781284030273_CH02_Pass3.indd 29 03/04/14 2:19 PM 30 CHAPTER 2 Sleep Disorders

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin

ECG Snore L Leg R Leg Cannula Thermister Thorax Abdomen SpO2

Periodic Limb Movements

FIGURE 2– 14 A series of six periodic limb movements on a 300-second epoch.

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin

ECG Snore L Leg R Leg Cannula Thermister Thorax Abdomen SpO2

Periodic Limb Movements in Both Legs

FIGURE 2– 15 Another 300-second epoch, this one showing four periodic limb movements.

 e sample epoch in Figure 2– 17 shows a patient that the technician make note of snores. In this case, the with sleep-related bruxism.  e events directly under the technician saw these events and noted that no snoring arrows show disruptions in the EEGs, electro- oculograms was present. (EOGs), chin EMG, and snore channel. When a patient  e arrows in the sample shown in Figure 2– 18 again clenches the jaw or grinds the teeth, many muscles in point to episodes of bruxism, or grinding of the teeth or the face, head, jaw, and neck will tighten, causing disrup- clenching of the jaw. tion in several channels, as shown in the fi gure. Heavy  e sample epoch in Figure 2– 19 shows another snoring can cause the same eff ect, so it is important example of sleep-related bruxism.  e episodes of jaw

9781284030273_CH02_Pass3.indd 30 03/04/14 2:19 PM Sleep-Related Movement Disorders 31

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin ECG Snore L Leg R Leg Cannula Thermister Thorax

Abdomen SpO2

FIGURE 2– 16 Limb movements in a 300-second epoch preceded by respiratory events.

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin ECG Snore L Leg R Leg Cannula

Thermister Thorax Abdomen SpO2

FIGURE 2– 17 Sleep-related bruxism.

clenching or teeth grinding are shown underneath the As the names suggest, body rocking refers to the entire arrows. Again, the muscle activity is shown throughout body moving back and forth, whereas head banging all the leads on the head. refers to movements of the head. A majority of patients aff ected with this disorder are infants, and it is consid- Sleep-Related Rhythmic Movement Disorder ered normal for infants to perform rhythmic motions like (RMD) this on occasion. By the age of fi ve, very few children have these symptoms.  ese movements can cause a distur- Also known as body rocking or head banging , sleep- bance to sleep, and may occasionally cause harm to the related rhythmic movement disorder is characterized by person infl icted or to the bed partner. repetitive body movements during drowsiness or sleep.

9781284030273_CH02_Pass3.indd 31 03/04/14 2:19 PM 32 CHAPTER 2 Sleep Disorders

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin ECG Snore L Leg R Leg Cannula

Thermister Thorax Abdomen SpO2

FIGURE 2– 18 Another episode of bruxism.

F3-M2 F4-M1 C3-M2 C4-M1 O1-M2 O2-M1 E1-M2 E2-M2 Chin ECG Snore L Leg R Leg Cannula

Thermister Thorax Abdomen SpO2

FIGURE 2– 19 A third example of sleep-related bruxism.

Benign Sleep Myoclonus of Infancy (BSMI) sleep or health, other than occasional arousals from Myoclonus , or limb jerks or movements during sleep, sleep. can occur at any age; however, it is very rarely seen in Propriospinal Myoclonus at Sleep Onset (PSM) infants. In the cases in which these repetitive leg jerks or movements have been noted during infancy, they Propriospinal myoclonus at sleep onset (PSM) are have typically resolved by the age of six months and events similar to sleep starts but mainly involve body do not appear to pose any serious threat to the infant’s movements in the abdominal, trunk, and neck areas.

9781284030273_CH02_Pass3.indd 32 03/04/14 2:19 PM Chapter Summary 33

 ey typically occur at sleep onset or during brief arous- causing a disruption. For example, if a person has PLMD, als from sleep. the bed partner is likely to experience sleep disruptions, causing EDS, , or insomnia.  is would be con- Sleep-Related Movement Disorder Due to sidered an environmental sleep disorder. Other factors Medical Disorder in the environment can cause these disruptions, such as poor room temperature or lighting, music, or leaving the  is disorder is classifi ed as movement disorders caused television on. by a medical condition. Certain medical conditions such as Parkinson’s disease can cause involuntary muscle movements during sleep, disrupting the sleep period. Chapter Summary Man has known about the existence of sleep disorders for Sleep-Related Movement Disorder Due to centuries, but until the past few decades has not exten- Medication or Substance sively researched and categorized them.  is category is reserved for movement disorders in Seven main classes of sleep disorders have been sleep that are caused by drug use or abuse. identifi ed by the American Academy of Sleep Medicine and are outlined and detailed in the ICSD-3.  e main Isolated Symptoms and Normal Variants classes of sleep disorders are insomnia, sleep-related breathing disorders, central disorders of hypersomno-  is group of sleep disorders consists of characteristics lence, circadian rhythm sleep–wake disorders, parasom- that are borderline abnormal, but are not otherwise spe- nias, sleep-related movement disorders, and other sleep cifi c disorders. disorders. Insomnia is the inability to initiate or maintain sleep Excessive Fragmentary Myoclonus or restful, restorative sleep. Insomnia can be caused by a Excessive fragmentary myoclonus is characterized by wide variety of factors. Paradoxical insomnia, also known frequent small twitches of fi ngers, toes, or muscles of as sleep state misperception, occurs when a person the mouth during wake or sleep.  ey are typically insig- believes they have slept very little or not at all during the nifi cant and benign in nature.  ey occur during NREM night, when in actuality they were asleep during much sleep, and persist for at least 20 minutes. or all of the night. Poor sleep hygiene can be a common contributor to insomnia, but is easily corrected. Proper Hypnagogic Foot Tremor (HFT) and Alternating Leg sleep hygiene refers to practices such as maintaining a Muscle Activation (ALMA) comfortable bedroom temperature, not consuming caf- feine shortly before bedtime, and not watching television Hypnagogic foot tremor (HFT) is characterized by rhyth- in bed. Alternating leg mic leg or foot movements at sleep onset. Sleep-related breathing disorders are also very com- muscle activation (ALMA) is similar, but presents itself mon, and occur most frequently in overweight and obese as a movement by one leg followed by a movement in individuals. Obstructive sleep apnea occurs when an the other leg.  ese events can cause brief arousals or individual is unable to maintain an open airway during awakenings from sleep but are otherwise typically benign the night, resulting in breathing stoppages. Apneas can in most patients. lead to excessive daytime sleepiness, morning headaches, frequent awakenings during the night, hypertension, Sleep Starts (Hypnic Jerks) memory loss, and other symptoms. Central sleep apnea A sleep start, also called a , is a sudden diff ers from OSA in that the patient is not attempting to muscle jerk or movement at sleep onset often accompa- breathe during the events. Rather than an obstruction in nied by feelings of surprise or fear.  ey often accompany the upper airway causing the apnea, the central nervous feelings of falling, but are typically benign.  ey can dis- system is the underlying cause. turb the sleep of the bed partner, and sometimes cause Central disorders of hypersomnolence cause exces- diffi culty returning to sleep. sive daytime sleepiness and include disorders such as narcolepsy that can be very debilitating and disruptive to normal daytime functions. Narcolepsy is character- Other Sleep Disorders ized by periods of REM at times when REM should not  ese disorders are not classifi ed in other catego- present itself, including during wakefulness. Symptoms ries because either they overlap categories or they are of narcolepsy can include excessive daytime sleepi- relatively new or proposed disorders that need more ness, hypnagogic hallucinations, sleep paralysis, and research. Although the ICSD-3 does not specifi cally list cataplexy. any sleep disorders in this category, the ICSD-2 listed Circadian rhythm sleep–wake disorders are char- environmental sleep disorder here. Environmental acterized by disruptions to the normal 24-hour sleep– sleep disorder can consist of many diff erent factors, wake cycle.  ese disruptions may be self-induced, including a disorder held by the bed partner that is externally induced, or caused by medical conditions or

9781284030273_CH02_Pass3.indd 33 03/04/14 2:19 PM 34 CHAPTER 2 Sleep Disorders

drugs. One of the most common circadian rhythm sleep Chapter 2 Questions disorders is jet lag disorder.  is occurs when a person Please consider the following questions as they relate to experiences insomnia or excessive daytime sleepiness the material in this chapter. as a result of traveling across two or more time zones. 1. What are the classes of sleep disorders? Why are Shift work is another common cause of circadian rhythm they grouped the way they are? disorder. Individuals who work shifts that overlap into 2. What are some important features of sleep their normal sleep schedule are more likely to experience hygiene? Why are these important practices for fatigue, EDS, insomnia, and lack of concentration. everyone to follow? Parasomnias are sleep disorders in which the indi- 3. Why is OSA important to diagnose and treat vidual performs some sort of undesirable or unwanted quickly and eff ectively? action during sleep.  ese can cause disturbances to 4. What is narcolepsy? What social impacts might the individual’s sleep and can put the patient and those narcolepsy have on an individual? nearby in physical danger. Sleepwalking is a parasomnia 5. How do delayed sleep–wake phase disorder and in which the individual will arise from bed during NREM advanced sleep–wake phase disorder diff er from sleep to walk, run, or perform other normal activities. In each other? some cases, the individual may jump out of a high win- 6. What is a night terror? In what ways can a night dow or assault the bed partner. Sleep enuresis is a para- terror be dangerous? somnia in which the individual has limited or no bladder 7. How does RLS diff er from PLMD? In what ways control during sleep. are they similar? Sleep-related movement disorders are a class of sleep 8. What are hypnic jerks, and how can they aff ect a disorders that cause smaller, less signifi cant, and often person’s sleep? rhythmic or repetitive movements during sleep. Perhaps the most common of these is periodic limb movement disorder. Patients with PLMD exhibit frequent, repetitive FOOTNOTES movements of the limbs during sleep.  ese movements 1. American Academy of Sleep Medicine. (2014). e international can disturb the sleep of the patient or the bed partner. classifi cation of sleep disorders (3rd ed.). Darien, IL: American Sleep-related bruxism is another common movement Academy of Sleep Medicine. disorder in which the individual grits or grinds the teeth 2. American Academy of Sleep Medicine. (2014). e international or clenches the jaw during sleep.  is can disrupt the classifi cation of sleep disorders (3rd ed.). Darien, IL: American sleep period and can damage the individual’s teeth. Academy of Sleep Medicine.  e fi nal class of sleep disorders is called other sleep 3. American Academy of Sleep Medicine. (2014). e international classifi cation of sleep disorders (3rd ed.). Darien, IL: American disorders, and is reserved for disorders that may overlap Academy of Sleep Medicine. other classes or that need to be researched further before 4. Sleep Management Services. (2002). Principles of polysomnogra- being properly classifi ed. phy . South Jordan, UT.

9781284030273_CH02_Pass3.indd 34 03/04/14 2:19 PM

Top View