Seeing the World Through Assorted Glasses (SWAG)
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Enrollment
- 15
- Locations
- 1
- Primary Endpoint
- Increase dim-light melatonin production
Study Overview
Brief Summary
The purpose of the study is to test the use of amber glasses at night as a method to block blue light from the eye, allowing the brain to produce a dim-light melatonin onset. The investigators hypothesize that blue-blocking will produce measurable benefits in subjectively and objectively rated sleep quality and mood as well as salivary melatonin levels during the night.
Detailed Description
Participants will complete a self-report battery containing measures of sleep quality, morningness-eveningness chronotype, and mood. Participants will then wear a wrist-worn accelerometer for 14 days to objectively record activity level and sleep quality. Participants will also fill out a daily sleep log and short self-report measures assessing sleep and mood. On days 4-7 and 11-14 of the study the participants will wear either amber or placebo control lenses prior to sleep onset in a randomized crossover design (i.e., participants will be randomized to wear either amber lenses or placebo lenses for the first part of the protocol and then switch to wear the opposite lenses for the second part of the protocol). Participants will spend nights 7 and 14 of the study in a sleep laboratory in order to obtain hourly melatonin samples and wear a wrist sleep monitor to non-invasively and objectively measure sleep state and quality using peripheral arterial tone and oxygen perfusion.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Crossover
- Primary Purpose
- Basic Science
- Masking
- Single (Participant)
Eligibility Criteria
- Ages
- 18 Years to 50 Years (Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Good physical health
- •Proficiency in written and spoken English
- •Reported average total sleep time <9 hours (so nights spent in sleep lab will not result in sleep deprivation)
Exclusion Criteria
- •Taking regular medication affecting sleep and/or mood
- •Travel across more than two time zones within the past month
- •Smoke > 5 cigarettes per day
- •Excessive caffeine use (>2 cups at one time or >500 mg daily)
- •No current Axis I Diagnostic and Statistical Manual of Mental Disorders (DSM-5) Disorder
- •No current use of street drugs
- •No history of sleep disorder/bipolar disorder/psychosis/seizure disorder/chronic medical condition
- •Night shift work within the past 2 months
Arms & Interventions
Amber Lenses
Participants will be randomized to participate in the amber lens condition first or second. Outcome measures to assess the effects of wearing amber lenses to block the blue light spectrum of light includes mood and sleep rating questionnaires (Positive and Negative Affect Scale, PANAS; Leeds Sleep Evaluation Questionnaire) as well as measuring the levels of melatonin the body is producing while wearing the glasses.
Intervention: Amber Lenses (Other)
Placebo Lenses
Participants will be randomized to participate in the placebo lens condition first or second. Outcome measures to assess the effects of wearing placebo lenses to allow all spectrums of light includes mood and sleep rating questionnaires (Positive and Negative Affect Scale, PANAS; Leeds Sleep Evaluation Questionnaire) as well as measuring the levels of melatonin the body is producing while wearing the glasses.
Intervention: Placebo Lenses (Other)
Outcomes
Primary Outcomes
Increase dim-light melatonin production
Time Frame: 4 days
Hourly saliva samples will be collected from participants at the end of each 4 night interval in order to measure levels of melatonin production.
Secondary Outcomes
- Improved subjective self-reported mood(4 days)
- Improved objective measures of sleep(4 days)
- Improved subjective self-reported sleep quality(4 days)
Investigators
Eric Youngstrom, PhD
Professor of Psychology and Psychiatry
University of North Carolina, Chapel Hill