NCT01586039

Brief Summary

The timing and quality of sleep is governed by environmental and physiologic factors. Environmental factors, especially ambient lighting can impact the circadian system and alter the timing and structure of sleep. Light exposure can also acutely alter neural activation state and impair sleep. These effects all demonstrate marked sensitivity to short-wavelength blue light with maximal sensitivity in the 460-480 nm range. The alerting effects of blue light in the evening persist for at least 3-4 hours after the lights are turned off, and can disturb subsequent sleep. Avoiding these deleterious effects of light exposure prior to sleep on subsequent sleep would be beneficial to sleep quality and potentially health. The investigators will compare the effects of two light sources, equated for visual stimulus (lux), on multiple non-visual responses to light. The investigators will compare a 90 lux exposure of a commercially available Compact Fluorescent Light (CFL) with a novel LED white light source that is depleted in the short-wavelength visible range (Biological Illumination LCC, FL). In a within-subject design, the investigators will test the hypotheses that exposure to a blue-depleted LED as compared to a CFL exposure at (1) 90 lux or (2) 50 lux will cause significantly:

  1. 1.Less melatonin suppression between melatonin onset and bedtime;
  2. 2.Less subjective and objective alerting responses before bedtime;
  3. 3.Less disruption of nocturnal sleep structure and quality.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
33

participants targeted

Target at P25-P50 for not_applicable

Timeline
Completed

Started Aug 2012

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

April 24, 2012

Completed
2 days until next milestone

First Posted

Study publicly available on registry

April 26, 2012

Completed
3 months until next milestone

Study Start

First participant enrolled

August 1, 2012

Completed
1.6 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 1, 2014

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

March 1, 2014

Completed
7 years until next milestone

Results Posted

Study results publicly available

March 5, 2021

Completed
Last Updated

September 14, 2021

Status Verified

September 1, 2021

Enrollment Period

1.6 years

First QC Date

April 24, 2012

Results QC Date

February 13, 2021

Last Update Submit

September 10, 2021

Conditions

Non-visual Photoreception

Keywords

MelatoninSleepLightAlertnessCircadian Rhythms

Outcome Measures

Primary Outcomes (1)

  • Melatonin Suppression

    Melatonin suppression is measured as the percentage of melatonin AUC relative to the AUC measured in dim light on the previous day. AUC was calculated during the 6 h of light exposure and the corresponding 6-h interval 24 hours earlier. Higher values indicate more light-induced melatonin suppression.

    6-h constant posture interval of the light exposure

Secondary Outcomes (4)

  • Sleep Structure

    8-h time in bed immediately following CFL/LED light exposure.

  • Sleep Quality

    First morning after 8-h time in bed immediately following CFL/LED light exposure.

  • Subjective Alerting Response

    6-h constant posture interval of the light exposure.

  • Objective Alerting Response

    6-h constant posture interval of the light exposure

Study Arms (4)

Compact Fluorescent Light 90 lux

ACTIVE COMPARATOR

90 lux exposure of a commercially available Compact Fluorescent Light (CFL).

Device: Visible light

Blue-depleted LED light 90 lux

EXPERIMENTAL

90 lux exposure of a novel LED white light source that is depleted in the short-wavelength visible range (Biological Illumination LCC, FL).

Device: Visible light

Compact Fluorescent Light 50 lux

ACTIVE COMPARATOR

50 lux exposure of a commercially available Compact Fluorescent Light (CFL).

Device: Visible light

Blue-depleted LED light 50 lux

EXPERIMENTAL

50 lux exposure of a novel LED white light source that is depleted in the short-wavelength visible range (Biological Illumination LCC, FL).

Device: Visible light

Interventions

Visible lightDEVICE

We will compare the effects of two light sources, equated for visual stimulus (lux), on multiple non-visual responses to light including melatonin suppression before bedtime. We will compare a 90 lux exposure of a commercially available Compact Fluorescent Light (CFL) with a novel LED white light source that is depleted in the short-wavelength visible range (Biological Illumination LCC, FL).

Blue-depleted LED light 50 luxBlue-depleted LED light 90 luxCompact Fluorescent Light 50 luxCompact Fluorescent Light 90 lux

Eligibility Criteria

Age18 Years - 30 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • (i) Aged between 18-30 years to reduce the confounding effects of lens aging on the transmission of light to the retina;
  • (ii) Non-smoking for at least 6 months;
  • (iii) Healthy (no medical, psychiatric or sleep disorders);
  • (iv) No clinically significant deviations from normal in medical history, vital signs, physical examination, blood chemistry and hematology, urine chemistry and ECG;
  • (v) Women of childbearing potential must agree to use an acceptable method of birth control, and must have a negative urine pregnancy test;
  • (vi) Body mass index of \> 18 or \< 30 kg/m2;
  • (vii) No drugs or medication likely to affect sleep or alertness, as determined by the investigators;
  • (viii) Habitual caffeine consumption \< 300mg per day on average;
  • (ix) Habitual alcohol consumption \< 10 alcoholic units per week on average.

You may not qualify if:

  • (i) History of alcohol or substance abuse;
  • (ii) Positive result on drugs of abuse screening;
  • (iii) Current or past history of sleep disorders, including but not limited to obstructive sleep apnea, or any significant sleep complaint;
  • (iv) Psychiatric disorder;
  • (v) Recent acute or chronic medical disorder, including but not limited to hepatic impairment and severe chronic obstructive pulmonary disease;
  • (vi) Visual disorder, including but not limited to color blindness, or family history of glaucoma;
  • (vii) History of intolerance or hypersensitivity to melatonin or melatonin agonists;
  • (viii) Pregnancy or lactation;
  • (ix) Shift work;
  • (x) Transmeridian travel (2 or more time zones) in past 2 months;
  • (xi) Any other reason as determined by the Principal Investigator.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Brigham and Women's Hospital

Boston, Massachusetts, 02115, United States

Location

Results Point of Contact

Title
Dr. Steven W. Lockley
Organization
Brigham and Women's Hospital
slockley@hms.harvard.edu
617-732-4977

Study Officials

  • Steven W Lockley, Ph.D.

    Brigham and Women's Hospital; Harvard Medical School

    PRINCIPAL INVESTIGATOR

Publication Agreements

PI is Sponsor Employee
No
Restrictive Agreement
No

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
SINGLE
Who Masked
PARTICIPANT
Purpose
BASIC SCIENCE
Intervention Model
FACTORIAL
Model Details: Stratified randomized crossover trial. Participants randomized between CFL and LED conditions stratified by light intensity (50 lux and 90 lux).
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Associate Professor of Medicine

Study Record Dates

First Submitted

April 24, 2012

First Posted

April 26, 2012

Study Start

August 1, 2012

Primary Completion

March 1, 2014

Study Completion

March 1, 2014

Last Updated

September 14, 2021

Results First Posted

March 5, 2021

Record last verified: 2021-09

Locations

US(1)