Periodic fatigue symptoms due to desynchronization in a patient with non-24-h sleep-wake syndrome

Psychiatry Clin Neurosci. 1998 Oct;52(5):477-81. doi: 10.1046/j.1440-1819.1998.00424.x.


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.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Body Temperature / physiology
  • Body Temperature / radiation effects
  • Chronotherapy
  • Circadian Rhythm / physiology
  • Circadian Rhythm / radiation effects
  • Fatigue / etiology*
  • Humans
  • Linear Models
  • Male
  • Monitoring, Ambulatory
  • Periodicity*
  • Photoperiod
  • Phototherapy
  • Sleep Wake Disorders / complications*
  • Sleep Wake Disorders / physiopathology
  • Sleep Wake Disorders / therapy
  • Work Schedule Tolerance / physiology