Seeing the World Through Assorted Glasses (SWAG)

Seeing the World Through Assorted Glasses (SWAG)

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.

Study Overview

• Status: Completed
• Conditions: Sleep
• Intervention / Treatment: Other: Amber Lenses; Other: Placebo Lenses

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 Type: Interventional
• Enrollment (Actual): 15
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • North Carolina
    • Chapel Hill, North Carolina, United States, 27599
      • University of North Carolina

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 50 years (ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: BASIC_SCIENCE
• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: SINGLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
OTHER: 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.	Other: Amber Lenses; Glasses fitted with amber lenses that block the blue spectrum of light (~470 nm) to be worn prior to desired sleep onset time.
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.	Other: Placebo Lenses; Glasses fitted with placebo lenses that allow all visible spectrum of light to be worn prior to desired sleep onset time.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Increase dim-light melatonin production	Hourly saliva samples will be collected from participants at the end of each 4 night interval in order to measure levels of melatonin production.	4 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Improved subjective self-reported mood	Participants will complete the Positive and Negative Affect Scale (PANAS) on a daily basis to measure self-reported mood.	4 days
Improved objective measures of sleep	Participants will complete nights in the sleep lab while wearing a watch device to measure arterial tone in order to objectively measure time spent in different sleep stages.	4 days
Improved subjective self-reported sleep quality	Participants will complete the Leeds Sleep Evaluation in order to assess self-report of sleep quality.	4 days

Collaborators and Investigators

• Sponsor: University of North Carolina, Chapel Hill
• Investigators: Principal Investigator: Eric Youngstrom, PhD, University of North Carolina, Chapel Hill

Study record dates

Study Major Dates

• Study Start: June 1, 2015
• Primary Completion (ACTUAL): May 1, 2016
• Study Completion (ACTUAL): May 1, 2016

Study Registration Dates

• First Submitted: June 13, 2015
• First Submitted That Met QC Criteria: June 24, 2015
• First Posted (ESTIMATE): June 29, 2015

Study Record Updates

• Last Update Posted (ESTIMATE): February 8, 2017
• Last Update Submitted That Met QC Criteria: February 6, 2017
• Last Verified: February 1, 2017

More Information

Terms related to this study

• Keywords: Melatonin; Sleep; Photoreceptor Cells, Vertebrate
• Other Study ID Numbers: 15-0389