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Symptoms and Signs of Sleeplessness and Circadian Rhythm Disorder

Doctor's Notes on Sleeplessness and Circadian Rhythm Disorder

A person's circadian rhythm (“biological clock”) regulates several biological processes according to an approximate 24-hour period. The malfunctioning the circadian system causes circadian rhythm disorders. The body systems with the most prominent circadian variations are the sleep-wake cycle, the temperature regulation system, and the endocrine system. Sleep-wake cycle is a type of circadian rhythm disorder and can be categorized into transient disorders (short-term) and chronic disorders. Transient disorders include jet lag, altered sleep schedule due to work hours or social responsibilities, and illness. Chronic biological clock disorders include irregular sleep-wake cycle, delayed sleep-phase syndrome (DSPS), and advanced sleep-phase syndrome (ASPS).

Symptoms of a biological clock sleep disorder include poor concentration, depression, difficulty concentrating, daytime sleepiness, problems falling asleep and staying asleep, non-restorative or poor quality sleep, problems with school or work performance, decreased cognitive skills, headaches, problems with coordination, and digestive problems.

Medical Author: John P. Cunha, DO, FACOEP
Medically Reviewed on 3/11/2019

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Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.