Sleep disorders can manifest as an inability to sleep (insomnia), daytime sleepiness, abnormal movements or behavior during sleep, or an inability to sleep at the appropriate time. Insomnia, defined as a persistent difficulty falling or staying asleep that impairs daytime function, is the most common sleep complaint. Insomnia can be caused by a variety of conditions, and can take many forms.
People with daytime sleepiness are fatigued, have a tendency to fall asleep in inappropriate places at inappropriate times, and have poor concentration, among other problems.
Some people have abnormal behaviors during sleep that may manifest as leg jerking or other body movements. Common causes of this disorder include restless leg movement disorder, periodic limb movement disorder, or seizures.
Other disorders, related to sleep deprivation, result in sleepiness and an inability to fall asleep at appropriate times.
There are four different types of major sleep disorders: dyssomnias, parasomnias, those caused by medical, neurological, or psychiatric problems, and proposed sleep disorders, a category for which little information is currently available Table 01. Dyssomnias produce insomnia or excessive sleepiness as a result of either disturbed nighttime sleep or impaired wakefulness. The dyssomnias are a mix of disorders originating in different body systems, and are further divided into intrinsic, extrinsic, and circadian–rhythm sleep disorders. Intrinsic disorders such as narcolepsy, obstructive sleep apnea syndrome (OSAS), and restless legs syndrome (RLS) occur as a result of internal causes. Extrinsic dis-orders typically occur as a result of environmental factors. Circadian–rhythm disorders are a result of sleep–wake cycle disruption.
Parasomnias are undesirable phenomena, such as night terrors or sleepwalking, that occur during sleep. Parasomnias include rapid eye movement (REM)–related parasomnias that interfere with sleep, as well as disorders of arousal and sleep–wake transition.
Disorders associated with medical, psychiatric, and neurologic problems include conditions such as chronic obstructive pulmonary disease (COPD), anxiety disorders, alcoholism, and dementia.
Proposed sleep disorders comprise a category for cases in which there is not enough information to make a standard sleep disorder diagnosis. For example, it is not known whether short sleepers and long sleepers should be categorized as patients with sleep disorder, or if their time asleep merely represents an extreme in the range of normal sleep physiology.
Table 1. Sleep Disorder Classifications
Dyssomnias Parasomnias Medical or psychiatric sleep disorders Proposed sleep disorders Intrinsic sleep disorders ?Arousal disorders ?Mental disorders Short sleeperLong sleeperSubwakefulness syndromeFragmentary myoclonusSleep hyperhidrosisMenstrual?associated sleep disorderPregnancy?associated sleep disorderTerrifying hypnagogic hallucinationsSleep?related neurogenic tachypneaSleep?related laryngospasmSleep choking syndrome Psychophysiologic insomniaSleep?state misperceptionIdiopathic insomniaNarcolepsyRecurrent hypersomniaIdiopathic hypersomniaObstructive sleep apnea syndrome (OSAS)Central sleep apnea syndromeCentral alveolar hypoventilation syndromePeriodic limb movements in sleep disorderRestless legs syndrome Confusional insomniaSleepwalkingSleep terrors PsychosesMood disordersAnxiety disordersPanic disordersAlcoholism Sleep?wake transition disorders Rhythmic movement disordersSleep startsSleep talkingNocturnal leg cramps ?Extrinsic sleep disorders Parasomnias associated with rapid eye movement (REM) ?Neurologic disorders Inadequate sleep hygieneEnvironmental sleep disorderAltitude insomniaAdjustment sleep disorderInsufficient sleep disorderLimit?setting sleep disorderSleep?onset associationdisorderFood allergy insomniaHypnotic?dependent sleep disorderAlcohol?dependent sleep disorderNocturnal eating (drinking) syndromeToxin?induced sleep disorder Impaired sleep?related penile erectionsSleep?related painful penile erectionsSleep paralysisREM?sleep?related sinus arrestNightmaresREM?sleep behavior disorder Cerebral degenerative disordersDementiaParkinsonismFatal familial insomniaSleep?related epilepsyElectrical status epilepticus of sleepSleep?related headaches Circadian rhythm sleep disorders ?Other parasomnias ?Other medical disorders Time?zone (jet lag) syndromeShift?work sleep disorderIrregular sleep?wake pattern disorderDelayed?sleep phase syndromeNon?24?hour sleep?wake disorderAdvanced sleep phase syndrome Sleep bruxismSleep enuresisSleep?related abnormal swallowing syndromeNocturnal paroxysmal dystoniaSudden unexplained nocturnal death syndromePrimary snoringInfant sleep apneaCongenital central hypoventilation syndromeSudden infant death syndromeBenign neonatal sleep myoclonus Sleeping sicknessNocturnal cardiac ischemiaChronic obstructive pulmonary diseaseSleep?related asthmaSleep?related gastroesophageal refluxPeptic ulcer diseaseFibromyalgia
Sleep disorders affect about one–third of the population. While individuals of all ages—even infants—can be affected, the elderly are especially prone to sleep disorders. Fortunately, most sleep disorders can be treated successfully through behavior modification and/or medication.
Medical or surgical problems, neurological disorders, and psychiatric disorders can all cause sleep disorders.
The numerous medical problems affecting sleep include asthma, heart disease, peptic ulcer disease, chronic obstructive pulmonary disease, and rheumatic disorders. Any sort of chronic pain may also impair sleep. Neurological disorders such as neurodegenerative diseases, strokes, headache syndromes, and neuromuscular disorders are associated with sleep disorders.
Psychiatric disorders such as depression, anxiety disorders, and panic attacks may be the underlying cause for approximately half of all cases of insomnia.
Drug and alcohol use can induce insomnia. Although some people use it to relax, alcohol, like other sedatives, disrupts sustained sleep. The nicotine found in cigarettes, as well as the caffeine in coffee, tea, and chocolate can also prevent you from falling asleep. In fact, for individuals sensitive to caffeine, even a few cups of coffee consumed in the morning can adversely affect sleep at night. Stimulant drugs such as amphetamines and antidepressants postpone sleep, as does phenylpropanolamine, which is present in many nonprescription decongestant treatments and diet aids.
Disruptions in internal sleep–wake cycles (circadian rhythm) can cause sleep disorders. Circadian rhythm refers to biologic changes throughout a 24–hour cycle. In mammals, nerve cell pacemakers control the biological rhythms involving the sleep–wake cycle.
Patients with circadian rhythm sleep disorders typically experience delayed–sleep phase syndrome, causing them to stay up well after midnight and wake up late in the morning. Delayed sleep phase syndrome is most commonly found in adolescents and young adults, and the onset of this disorder usually occurs around puberty.
Individuals with advanced–sleep phase syndrome retire early in the evening and awaken early in the morning.
Jet travel and night shift work contribute to circadian rhythm disruptions. Jet lag from rapid travel across time zones and shift–work sleep disorder are the most common circadian rhythm sleep disorders.
Stress and environmental factors can also lead to sleep problems. Stressful events related to financial problems, marital or family difficulties, or work demands are common causes of insomnia. For some patients, conditioning factors may cause sleep disruptions to persist even after the stressful event has passed.
Being at a high altitude alters breathing patterns, and thus can disturb sleep. People in this situation may awaken several times throughout the night, and will have poor–quality sleep. Although this sleep disturbance usually is worse during the first few nights spent at a high altitude, it may continue for a longer period of time.
Other factors, such as ventilation, humidity, noise, or an uncomfortable mattress can negatively affect sleep.
Sleep disorders can delay sleep, prevent sleeping through the night, and hinder alertness and coordination during the daytime Table 02. Lack of sleep leads to drowsiness and diminished attention and performance. Primary care physicians should be alert to the possibility of sleep disorders in patients who complain of vague symptoms such as fatigue and tiredness.
Table 2. Symptoms of Sleep Disorders
Insomnia Excessive daytime sleepiness or hypersomnia Difficulty falling asleepFrequent awakeningsEarly morning awakeningInsufficient sleepDaytime fatigue or sleepinessIrritability or lack of concentratio.Anxiety, sometimes depressionForgetfulnessPsychomotor symptoms Excessive daytime sleepinessFalling asleep in inappropriate places and circumstancesLack of relief of symptoms after additional sleepDaytime fatigueInability to concentrateImpairment of motor skills and cognition
Sleep disorder symptoms range from an inability to sleep to excessive drowsines. While insomnia—the inability to fall asleep or to maintain sleep through the night—is an obvious sleep disorder, other symptoms are not so clear–cut, and at first glance may not appear to be related to a sleep disorder.
Some individuals may sleep for very long periods (hypersomnia), or may experience excessive drowsiness and fall asleep at inappropriate times during the day. Some individuals never really feel rested, although they do not recall any difficulty sleeping at night.
Snoring and moving can disrupt sleep. Patients with sleep apnea usually snore a great deal and repeatedly wake up throughout the night, although they may have no recollection of these activities.
Periodic limb movement disorder may lead to poor–quality sleep and daytime drowsiness.
Some patients with parasomnias may experience episodes of sleepwalking or sleep terrors. Another parasomnia, rapid eye movement sleep behavior disorder, involves aggressive movements, reflecting dream activity during REM sleep. This violent activity sometimes injures a bed partner. REM sleep behavior disorder is associated with neurological disorders in about half the cases. In elderly patients, REM sleep behavior disorder may be associated with cerebrovascular disease, Parkinson’s disease, or Alzheimer’s disease.
Narcolepsy, a disorder involving excessive sleepiness, is usually associated with abrupt loss of muscle tone (cataplexy) and REM sleep reactions. Symptoms of narcolepsy include sleep paralysis, the inability to move after awakening from sleep, and hallucinations.
Overweight, middle–aged men are at risk for sleep apnea. Obesity often contributes to reduced space in the upper airways by increasing deposition of fat in the soft tissues of the pharynx. Superficial fat masses in the neck may compress the pharynx. The upper airways are narrowed during sleep, a condition that sets the stage for obstructive sleep apnea. Because of the narrowed upper airway, most individuals with obstructive sleep apnea frequently snore.
Although not limited by age or sex, obstructive sleep apnea typically occurs in middle–aged and elderly men who are slightly overweight (with a body mass more than 20% of normal), have a history of snoring, and often have mild to moderate hypertension.
Enlarged tonsils or an enlarged tongue also may place an individual at risk for sleep apnea episodes.
People who abuse drugs and alcohol are at risk for sleep disorders. Although alcohol and sedatives may help some people relax enough to fall asleep easily, using these drugs often leads to poor–quality sleep. Alcohol use also makes obstructive sleep apnea worse because the drug adversely affects upper airway muscles. Individuals who take certain types of sedatives and antidepressants, or who are alcoholics, may be at risk for REM sleep behavior disorder.
The risk for some sleep disorders is genetic.
Many sleep disorders can be hard to detect, and must be diagnosed by a skilled clinician. A sleep specialist should handle your treatment. Sleep medicine is a relatively newly developed subspecialty, giving rise to sleep disorder centers with specialized physicians and technical staff.
Your doctor will take a thorough patient history when you seek treatment for sleep disorders. Your doctor should explore any complaints of fatigue and tiredness to find out if they are related to a sleep disorder. In addition to your input, quite often information from a family member about symptoms such as snoring and drowsiness can provide vital clues.
Your doctor may ask you to complete a sleep log over a period of two weeks, or to come in for testing in a sleep lab to document your sleep pattern Table 03 . Many patients will benefit from referral to a sleep laboratory where specialized tests can be performed. If you spend the night in a lab, you will most likely be given a polysomnography, which is an electrophysiological test for sleep disorders.
Patients undergoing a polysomnogram can expect to spend the night in the center where their sleep will be assessed by simultaneously measuring and recording electrocardiograph findings, airflow, respiratory effort, oxygen saturation, and leg movements.
Another test conducted in a sleep laboratory—the Multiple Sleep Latency Test—is performed during the daytime, usually after a polysomnography has been performed. A patient undergoing the MSLT will take four to five naps throughout the day at two–hour intervals.
Table 3. 24?Hour Sleep/Wake Log
For each hour of the day, indicate sleep or wake time with an X in the appropriate box(es). Indicate naps with an N in the appropriate box(es), and indicate periods of extreme sleepinesswith an S in the appropriate box(es) Date Date Date Time Awake Asleep Time Awake Asleep Time Awake Asleep 12:00 ? ? 12:00 ? ? 12:00 ? ? 13:00 ? ? 13:00 ? ? 13:00 ? ? 14:00 ? ? 14:00 ? ? 14:00 ? ? 15:00 ? ? 15:00 ? ? 15:00 ? ? 16:00 ? ? 16:00 ? ? 16:00 ? ? 17:00 ? ? 17:00 ? ? 17:00 ? ? 18:00 ? ? 18:00 ? ? 18:00 ? ? 19:00 ? ? 19:00 ? ? 19:00 ? ? 20:00 ? ? 20:00 ? ? 20:00 ? ? 21:00 ? ? 21:00 ? ? 21:00 ? ? 22:00 ? ? 22:00 ? ? 22:00 ? ? 23:00 ? ? 23:00 ? ? 23:00 ? ? 24:00 ? ? 24:00 ? ? 24:00 ? ? 01:00 ? ? 01:00 ? ? 01:00 ? ? 02:00 ? ? 02:00 ? ? 02:00 ? ? 03:00 ? ? 03:00 ? ? 03:00 ? ? 04:00 ? ? 04:00 ? ? 04:00 ? ? 05:00 ? ? 05:00 ? ? 05:00 ? ? 06:00 ? ? 06:00 ? ? 06:00 ? ? 07:00 ? ? 07:00 ? ? 07:00 ? ? 08:00 ? ? 08:00 ? ? 08:00 ? ? 09:00 ? ? 09:00 ? ? 09:00 ? ? 10:00 ? ? 10:00 ? ? 10:00 ? ? 11:00 ? ? 11:00 ? ? 11:00 ? ? Exercise Exercise Exercise Treatment Treatment Treatment Sleep Quality Sleep Quality Sleep Quality Medications Medications Medications Comments Comments Comments
It is essential to address any medical, neurological, or psychological condition that may be causing or contributing to a sleep disorder.
Various medical problems such as peptic ulcer disease, rheumatic disorders, asthma, and neurological disorders such as headache syndromes and neuromuscular disorders frequently cause discomfort and pain, thus impairing sleep. Patients with psychological conditions such as anxiety and obsessive disorders often lie in bed preoccupied with their thoughts, which hinder sleep. For such patients, it is important to address the underlying conditions that may be causing or contributing to their sleep disorder.
Prevention and Screening
- Alcohol and AntidepressantsThe dos and don'ts of drinking when you take antidepressants are mostly don'ts.
- Antidepressant Treatment TimelineYou can expect to feel some relief from depression symptoms as early as the first week, but the full response could take months.
- Medications to Avoid While on AntidepressantsCould your antidepressant interact with something else you're taking?