[Circadian rhythm sleep disorders].
BACKGROUND
Circadian rhythm sleep disorders often lead to sleepiness and insomnia. These disorders are characterized by a misalignment between the intrinsic circadian rhythm and the external social and physical environment.


METHODS
This review is based on the authors' research and clinical experience and on articles identified by non-systematic searches in Pubmed and ISI Web of Knowledge.


RESULTS
Circadian rhythm sleep disorders are categorized into six subtypes: Delayed sleep-phase disorder, advanced sleep-phase disorder, irregular sleep-wake rhythm, free-running disorder, jet-lag and shift work disorder. By administering light and/or melatonin at appropriate times in accordance with the phase response curves of light and melatonin, most of the circadian rhythm sleep disorders can be treated effectively. The documented effects of these interventions are good, but well-controlled studies with long-term follow-up are needed.


CONCLUSIONS
The best-documented approaches to treating circadian rhythm sleep disorders are light and melatonin; physicians can easily administer both treatments.
Pallesen
Ståle
S
Det psykologiske fakultet, Christiesgt. 12, 5015 Bergen, Norway. staale.pallesen@psysp.uib.no
Bjorvatn
Bjørn
B
D002492:Central Nervous System Depressants / Q000008:administration & dosage; D002940:Circadian Rhythm / Q000502:physiology; D006801:Humans; D020179:Jet Lag Syndrome / Q000188:drug therapy; D008550:Melatonin / Q000008:administration & dosage; D020178:Sleep Disorders, Circadian Rhythm / Q000145:classification / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology; D012894:Sleep Stages / Q000502:physiology
D002492:Central Nervous System Depressants; D008550:Melatonin