Clinical Trials Logo

Clinical Trial Summary

Jet lag and some sleep disorders are caused by a disruption in an individual's "internal clock." Understanding the most effective way to quickly re-adjust the body's internal clock will be beneficial for treating individuals with these conditions. This study will evaluate the combined effectiveness of light and non-light therapies at regulating sleep cycles and improving sleep quality.


Clinical Trial Description

Circadian rhythm disorders are disruptions in an individual's circadian rhythm, or "internal body clock." This internal clock regulates the 24-hour cycle of biological processes in the body, including sleep and hormone production. Jet lag, delayed sleep phase syndrome, in which individuals fall asleep and wake up later than desired, and advanced sleep phase syndrome, in which individuals fall asleep and wake up earlier than desired, are all examples of circadian rhythm disorders. Because of the disruptive nature of these conditions, it is important to identify the quickest and most effective method for regulating the body and reestablishing normal sleep patterns. Light therapy, in which individuals are exposed to bright, artificial light, is currently used to treat these disorders. Melatonin, a hormone that regulates circadian rhythms, and methylxanthines, a class of stimulant medications, are other common non-light treatments. While each of these individual treatments has been proven effective, little is known about the combined effect of light and non-light treatments. The purpose of this study is to evaluate the safety and effectiveness of light therapy, melatonin, and methylxanthine, alone and in combination, at regulating circadian rhythms and improving sleep quality and cognitive function.

This study will enroll healthy individuals. Participants will first attend two screening visits, which will include a review of medical, psychiatric, and sleep histories; vital sign measurements; blood and urine collection; a physical examination; and an electrocardiogram. For 1 week, participants will record sleep habits in a diary and by telephone. They will also wear a device that monitors activity and light exposure levels. Eligible participants will then attend four 5-day inpatient visits at the Sleep and Chronobiology Laboratory at the University of Colorado at Boulder. During each of the four visits, participants will be randomly assigned to one of the following four treatments:

- Dim light therapy and placebo

- Bright light therapy and placebo

- Dim light therapy, melatonin, and methylxanthines

- Bright light therapy, melatonin, and methylxanthines

At each visit, participants will receive a different treatment. During these visits, participants will remain awake for up to 40 hours at a time, while their eye movements, and brain, muscle, heart, and breathing activity are monitored. Urine and saliva will be collected, and participants will undergo various cognitive performance testing measures. At 3-week intervals between each visit, participants will record sleep habits and will wear the activity and light exposure monitoring device. A sleep diary will also be maintained by participants for 3 weeks following the end of the last visit. ;


Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Basic Science


Related Conditions & MeSH terms


NCT number NCT00387179
Study type Interventional
Source National Heart, Lung, and Blood Institute (NHLBI)
Contact Gayle Wright, MS
Phone 303-735-1923
Email Sleep.Study@colorado.edu
Status Recruiting
Phase N/A
Start date October 2006
Completion date March 2010

See also
  Status Clinical Trial Phase
Completed NCT05346588 - THRIVE Feasibility Trial Phase 3
Recruiting NCT05991453 - Trajectories of Recovery After Intravenous Propofol Versus Inhaled VolatilE Anesthesia Trial N/A
Withdrawn NCT05096130 - Lifestyle Medicine Strategies for Combating Sleepiness and Fatigue in Professional Drivers N/A
Completed NCT01327040 - Light Sensitization Study N/A
Completed NCT00593736 - Efficacy of Ramelteon on Speeding Up Sleep in Subjects With Delayed Sleep Phase Syndrome Phase 2
Recruiting NCT04900675 - Bright Light Intervention to Reduce Students' Stress N/A
Completed NCT01881854 - Sleep Wake and Melatonin Pattern in Craniopharyngioma N/A
Completed NCT00246051 - Comprehensive Police Fatigue Management Program N/A
Recruiting NCT04690504 - Validation of Circadian Biomarkers in Patients With Sleep Disorders
Completed NCT03363529 - ROOM-LIGHT: Dynamic LED-light as Treatment for Depressed Patients in Inpatient Wards N/A
Recruiting NCT05701969 - Effect of Melatonin on Sleep Patterns of Resident Trainees During Night Float Shift Early Phase 1
Completed NCT00723580 - Actigraphic Analysis of Treatment Response N/A
Completed NCT00207285 - Sleep Disorders Management, Health and Safety in Police N/A
Not yet recruiting NCT06336525 - Adult Sleep Health in the Rural Appalachia and Mississippi Delta Region and Its Relationships With Cardiometabolic Health Disparities.
Not yet recruiting NCT06181110 - Sleep-Wake Patterns on Illness Trajectories and Treatment Response in MDD N/A
Recruiting NCT05618405 - Changes in Circadian Rhythm After Anaesthesia in Children
Completed NCT05684523 - Feasibility Study on the Use of Redormin®500 on Day-time Cognition Phase 4
Recruiting NCT05247125 - The Role of Circadian Factors in Regulation of Neuroplasticity in Ischemic Stroke (Interventional) Phase 4
Completed NCT04219566 - Vestibular Nerve Stimulation to Improve Sleep N/A
Completed NCT02199847 - Evaluation of the Effects of Pharmaton Tablets on Mental Performance and Physical Fatigue in Nurses Working Night Shift Phase 2