title: Periodic fatigue symptoms due to desynchronization in a patient with non-24-h sleep-wake syndrome.
abstract: A 43-year-old man complaining of recurrent fatigue symptoms and sleep disorders occurring periodically every 4 weeks was studied. Using a wrist worn actigraphy and an ambulatory rectal temperature monitoring apparatus, his sleep-wake cycle and rectal temperature were measured continuously for 4 months, while diagnostic evaluation and therapeutic interventions were conducted. It was found that after he gave up an attempt to keep to a 24-h-day, a free-running sleep wake pattern appeared but his fatigue symptoms disappeared. An analysis of the relationship between his sleep-wake cycle and the rectal temperature rhythm found that his fatigue symptoms did not appear when both rhythms were synchronized with each other. Artificial bright light therapy entrained him to a 24-h day without relapsing of fatigue symptoms. Desynchronization between a 24-h sleep-wake schedule and his circadian pacemaker may have caused his periodically appearing fatigue symptoms.
authors.affiliation: Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Ichikawa, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Shibui
authors.forename: M
authors.initials: M
authors.lastname: Uchiyama
authors.forename: H
authors.initials: H
authors.lastname: Iwama
authors.forename: S
authors.initials: S
authors.lastname: Ozaki
authors.forename: K
authors.initials: K
authors.lastname: Takahashi
authors.forename: M
authors.initials: M
authors.lastname: Okawa
mesh_terms: D000328:Adult; D001831:Body Temperature / Q000502:physiology / Q000528:radiation effects; D019454:Chronotherapy; D002940:Circadian Rhythm / Q000502:physiology / Q000528:radiation effects; D005221:Fatigue / Q000209:etiology*; D006801:Humans; D016014:Linear Models; D008297:Male; D018670:Monitoring, Ambulatory; D010507:Periodicity; D017440:Photoperiod; D010789:Phototherapy; D012893:Sleep Wake Disorders / Q000150:complications* / Q000503:physiopathology / Q000628:therapy; D014940:Work Schedule Tolerance / Q000502:physiology