The International Classification of Sleep Disorders (ICSD) is "a primary diagnostic, epidemiological and coding resource for clinicians and researchers in the field of sleep and sleep medicine". The ICSD was produced by the American Academy of Sleep Medicine (AASM) in association with the European Sleep Research Society, the Japanese Society of Sleep Research, and the Latin American Sleep Society. The classification was developed as a revision and update of the Diagnostic Classification of Sleep and Arousal Disorders (DCSAD) that was produced by both the Association of Sleep Disorders Centers (ASDC) and the Association for the Psychophysiological Study of Sleep and was published in the journal Sleep in 1979. A second edition, called ICSD-2, was published by the AASM in 2005. The third edition, ICSD-3, was released by the AASM in 2014. A text revision of the third edition (ICSD-3-TR) was published in 2023 by the AASM.
Milestones of sleep disorder classifications
YearICSDICDDSM1974DSM-III1975ICD-91979Nosology1980ICD-CMDSM-III1987DSM-III-R1991ICSD1992ICD-101994DSM-IV1997ICSD-R2000DSM-IV-TR2005ICSD-22006ICSD-2 Pocket Version2010ICD-10-CM2014ICSD-3DSM-52015ICD-11 Beta2022ICD-112023ICSD-3-TRDSM-5-TR
Introduction
In 1979, the first Diagnostic Classification of Sleep and Arousal Disorders (DCSAD) was developed by the Association of Sleep Disorders Centers (ASDC) and the Association for the Psychophysiological Study of Sleep. Disorders were divided into four main categories. Disorders of initiating and maintaining sleep (DIMS) – Insomnias Disorders of Excessive somnolence (DOES) – Hypersomnias Disorders of the Sleep-Wake Schedule – Circadian Disorders Dysfunctions Associated with Sleep, Sleep Stages, or Partial Arousals – Parasomnias
In 1990, the first comprehensive classification of disorders of sleep and arousal, the International Classification of Sleep Disorders (ICSD-1990), was developed by the American Academy of Sleep Medicine (AASM) in association with the European Sleep Research Society, the Japanese Society of Sleep Research, and the Latin American Sleep Society. 84 sleep disorders were inventoried, based on pathophysiological characteristics. It was later revised as the ICSD-R in 1997.
The International Classification of Sleep Disorders (ICSD) uses a multiaxial system for stating and coding diagnoses both in clinical reports or for database purposes. The axial system uses International Classification of Diseases (ICD-9-CM) coding wherever possible. Additional codes are included for procedures and physical signs of particular interest to sleep disorders clinicians and researchers. Diagnoses and procedures are listed and coded on three main "axes". The axial system is arranged as follows:
Axis A ICSD Classification of Sleep Disorders
Axis B ICD-9-CM Classification of Procedures
Axis C ICD-9-CM Classification of Diseases (nonsleep diagnoses).
ICSD-I (1990) and ICSD-Revised (1997)
Dyssomnias Intrinsic Sleep Disorders Extrinsic Sleep Disorders Circadian Rhythm Sleep Disorders Parasomnias Arousal Disorders Sleep-Wake Transition Disorders Parasomnias Usually Associated with REM Sleep Other Parasomnias Sleep Disorders Associated with Mental, Neurologic, or Other Medical Disorders Associated with Mental Disorders Associated with Neurologic Disorders Associated with Other Medical Disorders Proposed Sleep Disorders Shorter Sleeper Long Sleeper Menstrual-Associated Sleep Disorders
ICSD-2
In 2005, the International Classification of Sleep Disorders underwent minor updates and modifications resulting in version 2 (ICSD-2). ICSD-2 ICD-9-CM ICD-10-CMInsomnia: Insomnia is defined as the subjective perception of difficulty with sleep initiation, duration, consolidation, or quality that occurs despite adequate opportunity for sleep, and that results in some form of daytime impairment. Adjustment sleep disorder (acute insomnia) 307.41 F 51.02 Psychophysiological insomnia 307.42 F 51.04 Paradoxical insomnia (formerly sleep state misperception) 307.42 F 51.03 Idiopathic insomnia 307.42 F 51.01 Insomnia due to mental disorder 307.42 F 51.05 Inadequate sleep hygiene V69.4 Z72.821 Behavioral insomnia of childhood 307.42 — - Sleep-onset association type — z73.810 - Limit-setting sleep type — z73.811 - Combined type — Z73.812 Insomnia due to drug or substance 292.85 G47.02 Insomnia due to medical condition (code also the associated medical condition) 327.01 G47.01 Insomnia not due to a substance or known physiological condition, unspecified 780.52 F51.09 Physiological (organic) insomnia, unspecified; (organic insomnia, NOS) 327.00 G47.09Sleep-Related Breathing Disorders:Central sleep apnea syndromes Primary central sleep apnea 327.21 G47.31 Central sleep apnea due to Cheyne-Stokes breathing pattern 768.04 R06.3 Central sleep apnea due to high altitude periodic breathing 327.22 G47.32 Central sleep apnea due to a medical condition, not Cheyne-Stokes 327.27 G47.31 Central sleep apnea due to a drug or substance 327.29 F10-19 Primary sleep apnea of infancy 770.81 P28.3Obstructive sleep apnea syndromes Obstructive sleep apnea, adult 327.23 G47.33 Obstructive sleep apnea, pediatric 327.23 G47.33Sleep-related hypoventilation/hypoxemic syndromes Sleep-related non-obstructive alveolar hypoventilation, bidiopathic 327.24 G47.34 Congenital central alveolar hypoventilation syndrome 327.25 G47.35Sleep-related hypoventilation/hypoxemia due to a medical condition Sleep-related hypoventilation/hypoxemia due to pulmonary parenchymal or vascular pathology 327.26 G47.36 Sleep-related hypoventilation/hypoxemia due to lower airways obstruction 327.26 G47.36 Sleep-related hypoventilation/hypoxemia due to neuromuscular or chest wall disorders 327.26 G47.36Other sleep-related breathing disorder Sleep apnea/sleep related breathing disorder, unspecified 320.20 G47.30 Hypersomnias of Central Origin: Narcolepsy with cataplexy 347.01 G47.411 Narcolepsy without cataplexy 347.00 G47.419 Narcolepsy due to medical condition 347.10 G47.421 Narcolepsy, unspecified 347.00 G47.43 Recurrent hypersomnia 780.54 G47.13 - Kleine-Levin Syndrome 327.13 G47.13 - Menstrual-related hypersomnia 327.13 G47.13 Idiopathic hypersomnia with long sleep time 327.11 G47.11 Idiopathic hypersomnia without long sleep time 327.12 G47.12 Behaviorally induced insufficient sleep syndrome 307.44 F51.12 Hypersomnia due to medical condition 327.14 G47.14 Hypersomnia due to drug or substance 292.85 G47.14 Hypersomnia not due to a substance or known physiological condition 327.15 F51.1 Physiological (organic) hypersomnia, unspecified (organic hypersomnia, NOS) 327.10 G47.10Circadian Rhythm Sleep Disorders: Circadian rhythm sleep disorder, delayed sleep phase type 327.31 G47.21 Circadian rhythm sleep disorder, advanced sleep phase type 327.32 G47.22 Circadian rhythm sleep disorder, irregular sleep-wake type 327.33 G47.23 Circadian rhythm sleep disorder, free-running (non-entrained) type 327.34 G47.24 Circadian rhythm sleep disorder, jet lag type 327.35 G47.25 Circadian rhythm sleep disorder, shift work type 327.36 G47.26 Circadian rhythm sleep disorders due to medical condition 327.37 G47.27 Other circadian rhythm sleep disorder 327.39 G47.29 Other circadian rhythm sleep disorder due to drug or substance 292.85 G47.27Parasomnias:Disorders of arousal (from non-REM sleep) - Confusional arousals 327.41 G47.51 - Sleepwalking 307.46 F51.3 - Sleep terrors 307.46 F51.4Parasomnias usually associated with REM sleep - REM sleep behavior disorder (including parasomnia overlap disorder and status dissociatus) 327.42 G47.52 - Recurrent isolated sleep paralysis 327.43 G47.53 - Nightmare disorder 307.47 F51.5Other Parasomnias Sleep-related dissociative disorders 300.15 F44.9 Sleep enuresis 788.36 N39.44 Sleep-related groaning (catathrenia) 327.49 G47.59 Exploding head syndrome 327.49 G47.59 Sleep-related hallucinations 368.16 R29.81 Sleep-related eating disorder 327.49 G47.59 Parasomnia, unspecified 227.40 G47.50 Parasomnia due to a drug or substance 292.85 G47.54 Parasomnia due to a medical condition 327.44 G47.54Sleep-Related Movement Disorders: Restless legs syndrome (including sleep-related growing pains) 333.49 G25.81 Periodic limb movement sleep disorder 327.51 G47.61 Sleep-related leg cramps 327.52 G47.62 Sleep-related bruxism 327.53 G47.63 Sleep-related rhythmic movement disorder 327.59 G47.69 Sleep-related movement disorder, unspecified 327.59 G47.90 Sleep-related movement disorder due to drug or substance 327.59 G47.67 Sleep-related movement disorder due to medical condition 327.59 G47.67Isolated Symptoms, Apparently Normal Variants, and Unresolved Issues Long sleeper 307.49 R29.81 Short sleeper 307.49 R29.81 Snoring 786.09 R06.83 Sleep talking 307.49 R29.81 Sleep starts, hypnic jerks 307.47 R25.8 Benign sleep myoclonus of infancy 781.01 R25.8 Hypnagogic foot tremor and alternating leg muscle activation during sleep 781.01 R25.8 Propriospinal myoclonus at sleep onset 781.01 R25.8 Excessive fragmentary myoclonus 781.01 R25.8Other Sleep Disorders Other physiological (organic) sleep disorder 327.8 G47.8 Other sleep disorder not due to a known substance or physiological condition 327.8 G47.9 Environmental sleep disorder 307.48 F51.8Sleep disorders associated with conditions classifiable elsewhere Fatal familial insomnia 046.8 A81.8 Fibromyalgia 729.1 M79.7 Sleep-related epilepsy 345 G40.5 Sleep-related headaches 784.0 R51 Sleep-related gastroesophageal reflux disease 530.1 K21.9 Sleep-related coronary artery ischemia 411.8 I25.6 Sleep-related abnormal swallowing, choking, and laryngospasm 787.2 R13.1Other psychiatric/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 — —
The ICSD-2 thus lists 81 sleep disorder diagnostic categories divided in 8 major categories. Each diagnostic is detailed in a description that presents the diagnostic criteria. The 81 diagnostics are divided into 8 main categories, namely insomnias, sleep-related breathing disorders, hypersomnias of central origin, circadian rhythm sleep disorders, parasomnias, sleep-related movement disorders, isolated symptoms apparently normal variants and unresolved issues, other sleep disorders. The two last categories (i.e. sleep disorders associated with disorders classified elsewhere and psychiatric disorders frequently encountered in the differential diagnosis of sleep disorders) are presented in the appendices and count 13 diagnostics.
In 2006, a pocket version of the ICSD-2 was released. In this version, a pediatric section was added listing the following diagnostic categories: Behavioural Insomnia in Childhood Onset Type Limit Setting Type Primary Sleep Apnea of Infancy Obstructive Sleep Apnea, Pediatric Congenital Central Alveolar Hypoventilation Syndrome Sleep Enuresis Restless Legs Syndrome Sleep-related Rhythmic Movement Disorder
However, this classification brought some confusion into the field, which led to the revision of the classification in 2011. The classification was much more discussed by experts of the field and led to the third edition of the ICSD.
ICSD-3 (2014) and ICSD-3-TR (2023)
The revision of the ICSD-2 was firstly made by the AASM and other International Societies. This revision integrates pediatric diagnosis into clinical adult diagnosis (except for obstructive sleep apnea) and led to the third edition of the ICSD, which was released in 2014.