- Last edited on May 5, 2021
Circadian Rhythm Sleep-Wake Disorder, Non-24-Hour Sleep-Wake Type
Primer
Circadian Rhythm Sleep-Wake Disorder, Non-24-Hour Sleep-Wake Type is a circadian rhythm sleep-wake disorder characterized by symptoms of insomnia or excessive sleepiness due to abnormal synchronization between the 24-hour light-dark cycle and the individual's endogenous circadian rhythm. Non-24-hour sleep-wake type is most common among individuals who are blind, are visually impaired, or have decreased light perception.
Epidemiology
Prognosis
Comorbidity
Risk Factors
Diagnostic Criteria
Criterion A
A persistent or recurrent pattern of sleep disruption that is primarily due to an alteration of the circadian system or to a misalignment between the endogenous circadian rhythm and the sleep-wake schedule required by an individual’s physical environment or social or professional schedule.
Criterion B
The sleep disruption leads to excessive sleepiness or insomnia, or both.
Criterion C
The sleep disturbance causes clinically significant distress or impairment in social, occupational, and other important areas of functioning.
Specifier Criteria
Non-24-hour sleep-wake type specifier
Specify whether:
- Non-24-hour sleep-wake type: A pattern of sleep-wake cycles that is not synchronized to the 24-hour environment, with a consistent daily drift (usually to later and later times) of sleep onset and wake times.
Length Specifier
Length Specifier
Specify if:
- Episodic: Symptoms last at least
1
month but less than3
months. - Persistent: Symptoms last
3
months or longer. - Recurrent:
2
or more episodes occur within the space of1
year.