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Non-24-hour sleep-wake syndrome

Synonym(s) Hypernychthemeral syndrome
Prevalence Unknown
Inheritance Unknown
Age of onset All ages
  • G47.2
MeSH -
MedDRA -


Disease definition

Non-24-hour sleep-wake disorder (non-24 disorder), also known as hypernychthemeral syndrome, is a circadian rhythm sleep disorder characterized by non-synchronization to a 24-hour day leading to insomnia and daytime sleepiness with sometimes severe associated manifestations.

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