Sleep disorder

Sleep disorder
Specialty	Neurology, sleep medicine, psychiatry

A sleep disorder (somnipathy) is a medical disorder of the sleep patterns of a person or animal. Some sleep disorders are serious enough to interfere with normal physical, mental and emotional functioning. A test commonly ordered for some sleep disorders is the polysomnogram.

Common sleep disorders

The most common sleep disorders include:

• Bruxism: Involuntarily grinding or clenching of the teeth while sleeping
• Delayed sleep phase syndrome (DSPS): inability to awaken and fall asleep at socially acceptable times but no problem with sleep maintenance, a disorder of circadian rhythms. Other such disorders are advanced sleep phase syndrome (ASPS) and Non-24-hour sleep-wake syndrome (Non-24), both much less common than DSPS.
• Hypopnea syndrome: Abnormally shallow breathing or slow respiratory rate while sleeping
• Narcolepsy: Excessive daytime sleepiness, often culminating in falling asleep spontaneously and unwillingly at inappropriate times. Cataplexy, a sudden weakness in the motor muscles that could result in collapse to the floor is also common.
• Night terror, Pavor nocturnus, sleep terror disorder: abrupt awakening from sleep with behavior consistent with terror
• Parasomnias: Disruptive sleep-related events involving inappropriate actions during sleep stages - sleep walking and night-terrors are examples.
• Periodic limb movement disorder (PLMD): Sudden involuntary movement of arms and/or legs during sleep, for example kicking the legs. Also known as nocturnal myoclonus. See also Hypnic jerk, which is not a disorder.
• Rapid eye movement behavior disorder (RBD): Acting out violent or dramatic dreams while in REM sleep
• Restless legs syndrome (RLS): An irresistible urge to move legs. RLS sufferers often also have PLMD.
• Situational circadian rhythm sleep disorders: shift work sleep disorder (SWSD) and jet lag
• Obstructive sleep apnea: Obstruction of the airway during sleep, causing lack of sufficient deep sleep; often accompanied by snoring. Central sleep apnea is less common.
• Sleep paralysis is characterized by temporary paralysis of the body shortly before or after sleep. Sleep paralysis may be accompanied by visual, auditory or tactile hallucinations. Not a disorder unless severe. Often seen as part of Narcolepsy.
• Sleepwalking or somnambulism: Engaging in activities that are normally associated with wakefulness (such as eating or dressing), which may include walking, without the conscious knowledge of the subject

Broad classifications of sleep disorders

• Dyssomnias - A broad category of sleep disorders characterized by either hypersomnolence or insomnia. The three major subcategories include intrinsic (i.e., arising from within the body), extrinsic (secondary to environmental conditions or various pathologic conditions), and disturbances of circadian rhythm. MeSH
  • Insomnia
  • Narcolepsy
  • Obstructive sleep apnea
  • Restless leg syndrome
  • Periodic limb movement disorder
  • Hypersomnia
    • Recurrent hypersomnia - including Kleine-Levin syndrome
    • Posttraumatic hypersomnia
    • "Healthy" hypersomnia
  • Circadian rhythm sleep disorders
    • Delayed sleep phase syndrome
    • Advanced sleep phase syndrome
    • Non-24-hour sleep-wake syndrome
• Parasomnias
  • REM sleep behaviour disorder
  • Sleep terror
  • Sleepwalking (or somnambulism)
  • Bruxism (Tooth-grinding)
  • Bedwetting or sleep enuresis.
  • Sudden infant death syndrome (or SIDS)
  • Sleep talking (or somniloquy)
  • Sleep sex (or sexsomnia)
  • Exploding head syndrome - Waking up in the night hearing loud noises.
• Medical or Psychiatric Conditions that may produce sleep disorders
  • Psychoses (such as Schizophrenia)
  • Mood disorders
  • Depression
  • Anxiety
  • Panic
  • Alcoholism
• Sleeping sickness - a parasitic disease which can be transmitted by the Tsetse fly
• Snoring - Not a disorder in and of itself, but it can be a symptom of deeper problems.

Common causes of sleep disorders

Changes in life style, such as shift work change (SWC), can contribute to sleep disorders.

Other problems that can affect sleep:

• Anxiety
• Back pain
• Chronic pain
• Sciatica
• Neck pain
• Environmental noise
• Incontinence
• Various drugs - Many drugs can affect the ratio of the various stages of sleep, thus affecting the overall quality of sleep. Poor sleep can lead to accumulation of Sleep debt.
• Withdrawal - Drug Withdrawal during the 'cold-turkey' actual withdrawal stage can lead to loss of ability to get to sleep and can last for several days through to several weeks. It is particularly a pervasive symptom for withdrawal from Opiods and in particular Heroin, see Heroin#Withdrawal.
• Endocrine imbalance mainly due to Cortisol but not limited to this hormone. Hormone changes due to impending menstruation or during the menopause transition years.
• Chronobiological disorders, mainly Circadian rhythm disorders

A sleep diary can be used to help diagnose, and measure improvements in, sleep disorders. The Epworth Sleepiness Scale and the Morningness-Eveningness Questionnaire.

According to Dr. William Dement, of the Stanford Sleep Center, anyone who snores and has daytime drowsiness should be evaluated for sleep disorders .

Any time back pain or another form of chronic pain is present, both the pain and the sleep problems should be treated simultaneously, as pain can lead to sleep problems and vice versa.

General principles of treatment

Treatments for sleep disorders generally can be grouped into four categories:

• behavioral/ psychotherapeutic treatments
• rehabilitation/management
• medications
• other somatic treatments

None of these general approaches is sufficient for all patients with sleep disorders. Rather, the choice of a specific treatment depends on the patient's diagnosis, medical and psychiatric history, and preferences, as well as the expertise of the treating clinician. Often, behavioral/psychotherapeutic and pharmacological approaches are not incompatible and can effectively be combined to maximize therapeutic benefits. Management of sleep disturbances that are secondary to mental, medical, or substance abuse disorders should focus on the underlying conditions.

Medications and somatic treatments may provide the most rapid symptomatic relief from some sleep disturbances. Some disorders, such as narcolepsy, are best treated pharmacologically. Others, such as chronic and primary insomnia, may be more amenable to behavioral interventions, with more durable results.

Special equipment may be required for treatment of several disorders such as obstructive apnea, the circadian rhythm disorders and bruxism. In these cases, when severe, an acceptance of living with the disorder, however well managed, is often necessary.

Sleep medicine

main article: Sleep medicine

Due to rapidly increasing knowledge about sleep in the 20th century, including the discovery of REM sleep and sleep apnea, the medical importance of sleep was recognized. The medical community began paying more attention than previously to primary sleep disorders, such as sleep apnea, as well as the role and quality of sleep in other conditions. By the 1970s in the USA, clinics and laboratories devoted to the study of sleep and sleep disorders had been founded, and a need for standards arose.

Sleep Medicine is now a recognized subspecialty within internal medicine, family medicine, pediatrics, otolaryngology, psychiatry and neurology in the United States. Certification in Sleep Medicine shows that the specialist:

"has demonstrated expertise in the diagnosis and management of clinical conditions that occur during sleep, that disturb sleep, or that are affected by disturbances in the wake-sleep cycle. This specialist is skilled in the analysis and interpretation of comprehensive polysomnography, and well-versed in emerging research and management of a sleep laboratory."

Competence in sleep medicine requires an understanding of a plethora of very diverse disorders, many of which present with similar symptoms such as excessive daytime sleepiness, which, in the absence of volitional sleep deprivation, "is almost inevitably caused by an identifiable and treatable sleep disorder", such as sleep apnea, narcolepsy, idiopathic central nervous system (CNS) hypersomnia, Kleine-Levin syndrome, menstrual-related hypersomnia, idiopathic recurrent stupor, or circadian rhythm disturbances. Another common complaint is insomnia, a set of symptoms which can have a great many different causes, physical and mental. Management in the varying situations differs greatly and cannot be undertaken without a correct diagnosis.

Sleep dentistry (bruxism, snoring and sleep apnea), while not recognized as one of the nine dental specialties, qualifies for board-certification by the American Board of Dental Sleep Medicine (ABDSM). The resulting Diplomate status is recognized by the American Academy of Sleep Medicine (AASM), and these dentists are organized in the Academy of Dental Sleep Medicine (USA). The qualified dentists collaborate with sleep physicians at accredited sleep centers and can provide oral appliance therapy and upper airway surgery to treat or manage sleep-related breathing disorders.

In the UK, knowledge of sleep medicine and possibilities for diagnosis and treatment seem to lag. Guardian.co.uk quotes the director of the Imperial College Healthcare Sleep Centre: "One problem is that there has been relatively little training in sleep medicine in this country – certainly there is no structured training for sleep physicians." The Imperial College Healthcare site shows attention to obstructive sleep apnoea syndrome (OSA) and very few other disorders, specifically not including insomnia.

See also

• Auditory masking
• Chronotypes
• International Classification of Sleep Disorders
• Environmental noise health effects
• Reversed vegetative symptoms
• Sleep hygiene
• White noise machine

External links

• Australian fact sheets