CONTENTS
(1) An overview of Circadian Rhythm Sleep-Wake Disorders
(2) Types of Circadian Rhythm Sleep-Wake Disorders
(3) Authoritative online information
(4) Recommended book
(5) Related pages
(6) Resources for professionals
(7) Referrals
(1) An overview of Circadian Rhythm Sleep-Wake Disorders
According to the Cleveland Clinic, "circadian rhythm disorders are disruptions in a person’s circadian rhythm—a name given to the 'internal body clock' that regulates the (approximately) 24-hour cycle of biological processes in animals and plants. The key feature of circadian rhythm disorders is a continuous or occasional disruption of sleep patterns. The disruption results from either a malfunction in the 'internal body clock' or a mismatch between the 'internal body clock' and the external environment regarding the timing and duration of sleep. As a result of the circadian mismatch, individuals with these disorders usually complain of insomnia at certain times and excessive sleepiness at other times of the day, resulting in work, school, or social impairment."
(2) Types of Circadian Rhythm Sleep-Wake Disorders
According to the ICD-10 (International Classification of Diseases), there are six Circadian Rhythm Sleep Disorders:
Delayed sleep phase type: A sleep pattern that is delayed by two or more hours so that a person goes to sleep later at night and sleeps later in the morning.
Advanced sleep phase type: This disorder causes people to fall asleep several hours before a normal bedtime and wake up hours earlier than most people wake in the morning.
Irregular sleep wake type (see link below): This disorder occurs when a person's circadian rhythms to be so disorganized that there is no clear sleep or wake pattern. People with this sleep disorder may sleep off and on in a series of naps over a 24-hour period.
Free running type (see link below): A sleep disorder that causes a person's sleep time to shift a little later every day. Sleep times may go in and out of alignment with other people over time.
Jet lag type: Jet lag occurs when you travel across multiple time zones and have difficulty adjusting to the new schedule.
Shift work type (see link below): A non-traditional work schedule involving shifts that occur when most people are sleep can cause shift work disorder. The condition causes a person's sleep to be poor and results in consistent feelings of fatigue or exhaustion.
(3) Authoritative online information
Sleep Education (by the American Academy of Sleep Medicine) - Information about disorders
Non-24-Hour Sleep-Wake Rhythm (N24SWD) (free running type)
Sleep Education (by the American Academy of Sleep Medicine) - Information about treatment approaches
Circadian Sleep Disorders Network
Center for Environmental Therapeutics - Treatment of Circadian Rhythm Sleep Disorders
(4) Recommended book
Terman, M., & McMahan, I. (2013). Reset your inner clock: The drug free way to your best ever sleep, mood, and energy. Avery. [Amazon]
(5) Related pages
(7) Referrals