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Educational Activity

How the Circadian Rhythm Affects Sleep, Wakefulness, and Overall Health: Background for Understanding Shift Work Disorder

Andrew D. Krystal, MD, MS

Published: February 15, 2012

Article Abstract

It is estimated that 15 to 25% of the U.S. labor force works night, evening, or rotating shifts. These non-traditional schedules can affect the circadian rhythm, a self-sustained rhythm of biological processes that plays an important role in modulating sleep/wake function, resulting in circadian rhythm sleep disorder, shift work type, usually referred to as shift work disorder. The disorder consists of a constant or recurrent pattern of sleep interruption that results in insomnia w’ ‹hen sleep is needed and excessive sleepiness during waking hours. Clinicians need more information about the role of the circadian rhythm in human functioning as well as the pathophysiology, prevalence, and consequences of shift work disorder, so that they can recognize and diagnose this problem in clinical practice.


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The Journal of Clinical Psychiatry
The Primary Care Companion for CNS Disorders

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