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Synchronization and Desynchronization Between Circadian Rhythms in Patients With Delayed Sleep Phase Syndrome (DSPS)

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified January 2006 by Sheba Medical Center.
Recruitment status was:  Recruiting
Information provided by:
Sheba Medical Center Identifier:
First received: January 24, 2006
Last updated: December 14, 2006
Last verified: January 2006
This study's first aim is to widen the knowledge of the characteristics of delayed sleep phase disorder (DSPS) by focusing on the circadian rhythms of appetite regulation factors and their phase relations to the cycles of sleep-wake, melatonin, cortisol and body temperature. This study's second aim is to assess the influence of forced morning awakening, as a daily struggle faced by DSPS patients, upon the synchronization of these variables in DSPS patients. The investigators hypothesize that the chronic incompatibility between the endogenous sleep-wake rhythm of the DSPS patients and the morning wakefulness, as a social demand, may impair the synchronization between the different rhythms, as findings indicate in normal subjects under jet lag. And finally, the third aim of the study is to assess the influence of successful treatment with melatonin upon the phase locations of circadian rhythms of studied measures and the synchronization between them. These measures will be assessed in a controlled study, for 36 hours (sampled every 2 hours) under three distinct experimental conditions: first, under free sleep-wake conditions (ad-libitum bedtime and arousal); second, under restricted sleep-wake conditions (enforced morning wake-up); and finally, after 12 weeks of melatonin treatment.

Condition Intervention Phase
Delayed Sleep Phase Syndrome
Drug: Melatonin
Phase 1

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Educational/Counseling/Training

Resource links provided by NLM:

Further study details as provided by Sheba Medical Center:


Ages Eligible for Study:   22 Years to 50 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Clinical diagnosis of DSPS

Exclusion Criteria:

  • BMI higher than 28 or lower than 22
  • Shift-work
  • Chronic disease and chronic medication use
  Contacts and Locations
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Please refer to this study by its identifier: NCT00282061

Contact: Julia Tamir, MA 972-54-811146

The Institute for Sleep and Fatigue Medicine, Sheba Medical Center Recruiting
Tel Hashomer, Israel
Contact: Julia Tamir, MA    972-54-4811146   
Sponsors and Collaborators
Sheba Medical Center
Principal Investigator: Yaron Dagan, MD, PhD Sheba Medical Center
  More Information Identifier: NCT00282061     History of Changes
Other Study ID Numbers: SHEBA-04-3497-YD-CTIL
Study First Received: January 24, 2006
Last Updated: December 14, 2006

Keywords provided by Sheba Medical Center:
3 conditions in a within-subject design:
1-ad-lib sleep wake
2-forced morning wake-up
3- ad-lib sleep wake after treatment with melatonin

Additional relevant MeSH terms:
Sleep Disorders, Circadian Rhythm
Pathologic Processes
Chronobiology Disorders
Nervous System Diseases
Sleep Wake Disorders
Occupational Diseases
Mental Disorders
Molecular Mechanisms of Pharmacological Action
Protective Agents
Physiological Effects of Drugs
Central Nervous System Depressants processed this record on April 21, 2017