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Extended Work Schedules, Sleep Loss and Health (EW and EWD)

This study has been completed.
Information provided by (Responsible Party):
University of Chicago Identifier:
First received: October 1, 2009
Last updated: September 29, 2016
Last verified: September 2016
This study aims to determine whether abnormal bodily rhythms contribute to elevate the risk of diabetes, independently of the amount of sleep loss.

Condition Intervention
Sleep Behavioral: Fixed restricted bedtimes Behavioral: Sleep restriction with circadian misalignment

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Official Title: Extended Work Schedules and Health: Role of Sleep Loss

Further study details as provided by University of Chicago:

Enrollment: 49
Study Start Date: January 2003
Study Completion Date: September 2009
Primary Completion Date: December 2007 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Sleep loss and circadian alignment
Sleep restriction without circadian misalignment
Behavioral: Fixed restricted bedtimes
Sleep restricted to 5 hours per night for 8 nights
Experimental: Sleep loss and circadian misalignment Behavioral: Sleep restriction with circadian misalignment
Sleep restricted to 5 h per day for 8 days, alternating night sleep and day sleep


Ages Eligible for Study:   21 Years to 39 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • normal healthy men and women between the ages of 21 years and 39 years (inclusive) with normal weight (i.e., body mass index under 28 kg/m2 in men, 27 kg/m2 in women)
  • normal findings on clinical examination, normal results on routine laboratory tests, normal EKG, normal glucose tolerance test, negative pregnancy test for women
  • no personal history of psychiatric or endocrine illness
  • no personal history of sleep disorder, usual total sleep time of at least 7 hours
  • only female volunteers with normal ovulatory cycles will be included

Exclusion Criteria:

  • subjects with irregular life habits (shiftworkers and subjects having traveled across time zones less than one month prior to the beginning of the baseline study)
  • subjects taking any medication (including hormonal contraceptive therapy), and smokers are excluded
  • subjects with significant sleep apnea (apnea index above 10) or significant arousal-associated periodic leg movements are excluded
  Contacts and Locations
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Please refer to this study by its identifier: NCT00989534

United States, Illinois
The University of Chicago
Chicago, Illinois, United States, 60637
Sponsors and Collaborators
University of Chicago
  More Information

Responsible Party: University of Chicago Identifier: NCT00989534     History of Changes
Other Study ID Numbers: 11403A
Study First Received: October 1, 2009
Last Updated: September 29, 2016

Keywords provided by University of Chicago:
shift work
Affects of shift work and sleep loss on health processed this record on July 28, 2017