Classification of sleep disorders

Frequently used classification systems are ICD–10 and ICSD–2.

ICD–10

The 10th Revision of the International Classification of Diseases (ICD-10) developed by the WHO is mainly based on clinical criteria and distinguishes between nonorganic and organic sleep disorders.

Nonorganic sleep disorders

The majority of sleep disorders (2/3) are nonorganic, i.e. have emotional causes. They can generally be divided into nonorganic insomnias (insufficient duration and quality of sleep), nonorganic hypersomnias (excessive tiredness or sleep attacks during the day), nonorganic disorders of the sleep-wake rhythm (imbalance between the individual sleep-wake rhythm and that of the environment) and parasomnias (functional disorders associated with sleep, e.g. sleep walking, pavor nocturnus, nightmares and nocturnal bruxism). Apart from the main diagnosis of sleep disorders, there may be a variety of comorbidities, among which anxiety, stress-related and somatoform disorders are most prominent (41%), followed by affective disorders (depression) (31%) and disorders due to use of alcohol or drugs (15%).

Organic sleep disorders

One third of sleep disorders are organic. They can be split up into insomnias, hypersomnias, disorders of the sleep-wake cycle, sleep apnea (repeated nocturnal apneas with decrease of the blood oxygen level), narcolepsy (excessive daytime sleepiness) and others such as parasomnias (e.g. nocturnal enuresis, REM behavior disorder, primary snoring), but also movement disorders such as restless legs syndrome (RLS) (nocturnal dysesthesias in the extremities with an urge to move) and periodic limb movements (PLM).

ICSD–2

The International Classification of Sleep Disorders (ICSD-2), which apart from clinical criteria is also based on sleep laboratory findings, distinguishes a total number of more than 100 (!) different sleep disorders. They are sub-classified into 8 chapters and 2 appendices:

  • insomnia
  • sleep-related breathing disorders
  • hypersomnias of central origin not due to a circadian rhythm sleep disorder, sleep-related breathing disorder, or other cause of disturbed nocturnal sleep
  • circadian rhythm sleep disorders
  • parasomnias
  • sleep-related movement disorders
  • isolated symptoms, apparently normal variants and unresolved issues
  • other sleep disorders
  • sleep disorders associated with conditions classifiable elsewhere (appendix A)
  • other psychiatric and behavioral disorders frequently encountered in the differential diagnosis of sleep disorders (appendix B)

The great number of different sleep disorders requires extensive diagnostic and therapeutic skills, which are guaranteed at the Sleep Laboratory Rudolfinerhaus as it fully meets the sleep medical quality and accreditation standards of the interdisciplinary Austrian Sleep Research Association (ASRA).

International Classification of Sleep Disorders– ICSD-2

1. Insomnia
  • Adjustment insomnia (acute insomnia) 307.41
  • Psychophysiological insomnia 307.42
  • Paradoxical insomnia 307.42
  • Idiopathic insomnia 307.42
  • Insomnia due to mental disorder 327.02
  • Inadequate sleep hygiene V69.4
  • Behavioral insomnia of childhood V69.5
  • Insomnia due to drug or substance 292.85
  • Insomnia due to medical condition 327.01
  • Insomnia not due to substance or known physiological condition, unspecified (nonorganic insomnia) 780.52
  • Physiological (organic) insomnia, unspecified 327.00
2. Sleep–related breathing disorders
  • Central sleep apnea syndromes
    • Primary central sleep apnea 327.21
    • Central sleep apnea due to Cheyne Stokes breathing pattern 786.04
    • Central sleep apnea due to high-altitude periodic breathing 327.22
    • Central sleep apnea due to drug or substance 327.29
    • Primary sleep apnea of infancy (formerly primary sleep apnea of newborn) 770.81
  • Obstructive sleep apnea syndromes
    • Obstructive sleep apnea, adult 327.23
    • Obstructive sleep apnea, pediatric 327.23
  • Sleep-related hypoventilation/hypoxemic syndromes
    • sleep-related nonobstructive alveolar hypoventilation, idiopathic 327.24
    • congenital central alveolar hypoventilation syndrome 327.25
3 Hypersomnias of central origin

not due to a circadian rhythm sleep disorder,sleep-related breathing disorder, or other cause of disturbed nocturnal sleep

  • Narcolepsy with cataplexy 347.01
  • Narcolepsy without cataplexy 347.00
  • Narcolepsy due to medical condition 347.11/347.10
  • Narcolepsy, unspecified 347.00
  • Recurrent hypersomnias
    • Kleine-Levin syndrome 327.13
    • Menstrual-related hypersomnia 327.13
  • Idiopathic hypersomnia with long sleep time 327.11
  • Idiopathic hypersomnia without long sleep time 327.12
  • Behaviorally induced insufficient sleep syndrome 307.44
  • Hypersomnia due to medical condition 327.14
  • Hypersomnia due to drug or substance 292.85
  • Hypersomnia not due to substance or known physiological condition (nonorganic hypersomnia) 327.15
4. Circadian rhythm sleep disorders
  • Circadian rhythm sleep disorder, delayed sleep phase type (delayed sleep phase disorder) 327.31
  • Circadian rhythm sleep disorder, advanced sleep phase type (advanced sleep phase disorder) 327.32
  • Circadian rhythm sleep disorder, irregular sleep-wake type (irregular sleep-wake rhythm) 327.33
  • Circadian rhythm sleep disorder, free-running type (nonentrained type) 327.34
  • Circadian rhythm sleep disorder, jet lag type (jet lag disorder) 327.35
  • Circadian rhythm sleep disorder, shift work type (shift work disorder) 327.36
  • Circadian rhythm sleep disorder due to medical condition 327.37
  • Other circadian rhythm sleep disorder (circadian rhythm disorder, NOS) 327.39
  • Other circadian rhythm sleep disorder due to drug or substance 292.85
5. Parasomnias
  • Disorders of arousal (from non-REM sleep)
    • Confusional arousals 327.41
    • Sleepwalking 307.46
    • Sleep terrors 307.46
  • Parasomnias usually associated with REM sleep
    • REM sleep behavior disorder (including parasomnia overlap disorder and status dissociatus) 327.42
    • Recurrent isolated sleep paralysis 327.43
    • Nightmare disorder 307.47
  • Other parasomnias
    • Sleep-related dissociative disorder 300.15
    • Sleep enuresis 788.36
    • Sleep-related groaning (catathrenia) 327.49
    • Exploding head syndrome 327.49
    • Sleep-related hallucinations 368.16
    • Sleep–related eating disorder 327.49
    • Parasomnia, unspecified 327.40
    • Parasomnia due to drug or substance 292.85
    • Parasomnia due to medical condition 327.44
6. Sleep–related movement disorders
  • Restless legs syndrome 333.99
  • Periodic limb movement disorder 327.51
  • Sleep-related leg cramps 327.52
  • Sleep-related bruxism 327.53
  • Sleep-related rhythmic movement disorder 327.59
  • Sleep-related movement disorder, unspecified 327.59
  • Sleep-related movement disorder due to drug or substance 327.59
  • Sleep-related movement disorder due to medical condition 327.59
7. Isolated symptoms, normal variants and unresolved issues
  • Long sleeper
  • Short sleeper
  • Snoring 786.09
  • Sleep talking
  • Sleep starts (hypnic jerks)
  • Benign sleep myoclonus of infancy
  • Hypnagogic foot tremor and alternating leg muscle activation during sleep
  • Propriospinal myoclonus at sleep onset
  • Excessive fragmentary myoclonus
8. Other sleep disorders
  • Other physiological (organic) sleep disorders 327.8
  • Other sleep disorders not due to substance or known physiological condition 307.40
  • Environmental sleep disorder 307.48
Appendix A: Sleep disorders associated with conditions classifiable elsewhere
  • Fatal familial insomnia
  • Fibromyalgia
  • Sleep-related epilepsy
  • Sleep-related headaches
  • Sleep-related gastroesophageal reflux disease
  • Sleep-related coronary ischemia
  • Sleep-related abnormal swallowing, choking, and laryngospasm
Appendix B: Other psychiatric and behavioral disorders frequently encountered in the differential diagnosis of sleep disorders
  • Mood disorders
  • Anxiety disorders
  • Somatoform disorders
  • Schizophrenia and other psychotic disorders
  • Disorders usually first diagnosed in infancy, childhood, or adolescence
  • Personality disorders