non 24 sleep disorderJoe Segen2016-11-11T12:42:36+00:00
non 24 sleep disorder
Definition A chronic circadian rhythm sleep disorder, defined* as insomnia or excessive sleepiness related to abnormal synchronisation between the 24-hour light–dark cycle and the endogenous circadian rhythms of sleep and wake propensity.
*In the International Classification of Sleep Disorders Diagnostic and Coding Manual
Comment Most individuals with non-24 are blind, and become symptomatic when their non-entrained (free-running) endogenous circadian rhythm (clock) drifts out of alignment with a desired or conventional sleep–wake schedule. Non-24 disorder debilitates because it is incompatible with most social and professional obligations. It can also occur in sighted people; nobody knows why.
Synonyms Circadian rhythm sleep disorder—free-running type, circadian rhythm sleep disorder—nonentrained type, free running disorder, hypernychthemeral disorder, non 24, non-24-hour circadian rhythm disorder, non-24-hour sleep–wake disorder