Trial Outcomes & Findings for Bright Light Therapy for Treatment of Sleep Problems Following Mild Traumatic Brain Injury (NCT NCT02374918)

NCT ID: NCT02374918

Last Updated: 2021-06-24

Results Overview

The Pittsburgh Sleep Quality Index (PSQI) subscale measurement that was used is overall sleep quality, which is derived from question 6 on the assessment and uses a Likert scale of 0 to 3. A score of 0 represents "very good" sleep quality (better outcome), while a measurement of 3 represents "very bad" sleep quality (worse outcome).

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

77 participants

Primary outcome timeframe

Post 6-week intervention

Results posted on

2021-06-24

Participant Flow

Participants were recruited from around the city of Tucson. The first participant was enrolled in December 2014. The Effect Localization Arm completed enrollment in April 2015 and the Treatment Arm completed enrollment in May 2019.

No pre-assignment criteria were needed after enrollment but before study group assignment for the Effect Localization Arm. For the Treatment Arm, participants went through a screening visit before study group assignment and were excluded based on the inclusion/exclusion criteria.

Participant milestones

Participant milestones
Measure
mTBI Wavelength-1 Bright Light
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
mTBI Wavelength-2 Bright Light
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
HC Wavelength-1 Bright Light
30 minutes of light exposure HC wavelength-1 bright light: 30 minutes of light exposure
HC Wavelength-2 Bright Light
30 minutes of light exposure HC wavelength-2 bright light: 30 minutes of light exposure
Overall Study
STARTED
17
18
22
20
Overall Study
COMPLETED
14
17
18
18
Overall Study
NOT COMPLETED
3
1
4
2

Reasons for withdrawal

Reasons for withdrawal
Measure
mTBI Wavelength-1 Bright Light
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
mTBI Wavelength-2 Bright Light
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
HC Wavelength-1 Bright Light
30 minutes of light exposure HC wavelength-1 bright light: 30 minutes of light exposure
HC Wavelength-2 Bright Light
30 minutes of light exposure HC wavelength-2 bright light: 30 minutes of light exposure
Overall Study
Protocol Violation
2
0
2
1
Overall Study
Withdrawal by Subject
1
1
1
0
Overall Study
Lack of Efficacy
0
0
1
1

Baseline Characteristics

The RPCSQ was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
mTBI Wavelength-1 Bright Light
n=17 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
mTBI Wavelength-2 Bright Light
n=18 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
HC Wavelength-1 Bright Light
n=18 Participants
30 minutes of light exposure HC wavelength-1 bright light: 30 minutes of light exposure
HC Wavelength-2 Bright Light
n=18 Participants
30 minutes of light exposure HC wavelength-2 bright light: 30 minutes of light exposure
Total
n=71 Participants
Total of all reporting groups
Age, Categorical
<=18 years
3 Participants
n=17 Participants
1 Participants
n=18 Participants
1 Participants
n=18 Participants
2 Participants
n=18 Participants
7 Participants
n=71 Participants
Age, Categorical
Between 18 and 65 years
14 Participants
n=17 Participants
17 Participants
n=18 Participants
17 Participants
n=18 Participants
16 Participants
n=18 Participants
64 Participants
n=71 Participants
Age, Categorical
>=65 years
0 Participants
n=17 Participants
0 Participants
n=18 Participants
0 Participants
n=18 Participants
0 Participants
n=18 Participants
0 Participants
n=71 Participants
Age, Continuous
25.53 years
STANDARD_DEVIATION 8.65 • n=17 Participants
26.23 years
STANDARD_DEVIATION 7.62 • n=18 Participants
21.61 years
STANDARD_DEVIATION 2.86 • n=18 Participants
22.28 years
STANDARD_DEVIATION 4.03 • n=18 Participants
23.95 years
STANDARD_DEVIATION 6.41 • n=71 Participants
Sex: Female, Male
Female
12 Participants
n=17 Participants
10 Participants
n=18 Participants
9 Participants
n=18 Participants
10 Participants
n=18 Participants
41 Participants
n=71 Participants
Sex: Female, Male
Male
5 Participants
n=17 Participants
8 Participants
n=18 Participants
9 Participants
n=18 Participants
8 Participants
n=18 Participants
30 Participants
n=71 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
2 Participants
n=17 Participants
3 Participants
n=18 Participants
3 Participants
n=18 Participants
6 Participants
n=18 Participants
14 Participants
n=71 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
15 Participants
n=17 Participants
15 Participants
n=18 Participants
15 Participants
n=18 Participants
12 Participants
n=18 Participants
57 Participants
n=71 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
n=17 Participants
0 Participants
n=18 Participants
0 Participants
n=18 Participants
0 Participants
n=18 Participants
0 Participants
n=71 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
n=17 Participants
0 Participants
n=18 Participants
0 Participants
n=18 Participants
0 Participants
n=18 Participants
0 Participants
n=71 Participants
Race (NIH/OMB)
Asian
1 Participants
n=17 Participants
0 Participants
n=18 Participants
1 Participants
n=18 Participants
3 Participants
n=18 Participants
5 Participants
n=71 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=17 Participants
0 Participants
n=18 Participants
0 Participants
n=18 Participants
0 Participants
n=18 Participants
0 Participants
n=71 Participants
Race (NIH/OMB)
Black or African American
0 Participants
n=17 Participants
1 Participants
n=18 Participants
0 Participants
n=18 Participants
0 Participants
n=18 Participants
1 Participants
n=71 Participants
Race (NIH/OMB)
White
16 Participants
n=17 Participants
17 Participants
n=18 Participants
15 Participants
n=18 Participants
15 Participants
n=18 Participants
63 Participants
n=71 Participants
Race (NIH/OMB)
More than one race
0 Participants
n=17 Participants
0 Participants
n=18 Participants
0 Participants
n=18 Participants
0 Participants
n=18 Participants
0 Participants
n=71 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
n=17 Participants
0 Participants
n=18 Participants
2 Participants
n=18 Participants
0 Participants
n=18 Participants
2 Participants
n=71 Participants
Region of Enrollment
United States
17 participants
n=17 Participants
18 participants
n=18 Participants
18 participants
n=18 Participants
18 participants
n=18 Participants
67 participants
n=71 Participants
Post-Concussive Symptoms - Rivermead Post-Concussion Symptoms Questionnaire
RPQ3
3.3 units on a scale
STANDARD_DEVIATION 3 • n=17 Participants • The RPCSQ was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
3.5 units on a scale
STANDARD_DEVIATION 2.5 • n=18 Participants • The RPCSQ was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
3.4 units on a scale
STANDARD_DEVIATION 2.7 • n=35 Participants • The RPCSQ was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
Post-Concussive Symptoms - Rivermead Post-Concussion Symptoms Questionnaire
RPQ13
12.3 units on a scale
STANDARD_DEVIATION 13 • n=17 Participants • The RPCSQ was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
15.9 units on a scale
STANDARD_DEVIATION 8 • n=18 Participants • The RPCSQ was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
14.1 units on a scale
STANDARD_DEVIATION 10.9 • n=35 Participants • The RPCSQ was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
Sleep Quality - PSQI
1.44 units on a scale
STANDARD_DEVIATION 0.7 • n=17 Participants • The PSQI was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
1.76 units on a scale
STANDARD_DEVIATION 0.66 • n=18 Participants • The PSQI was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
1.60 units on a scale
STANDARD_DEVIATION 0.69 • n=35 Participants • The PSQI was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
Actigraphy - Sleep Efficiency
82.53 Percentage of time asleep
STANDARD_DEVIATION 4.83 • n=17 Participants • Actigraphy was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
80.98 Percentage of time asleep
STANDARD_DEVIATION 4.71 • n=18 Participants • Actigraphy was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
81.73 Percentage of time asleep
STANDARD_DEVIATION 4.63 • n=35 Participants • Actigraphy was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
Actigraphy - Wake After Sleep Onset (WASO)
11.2 Minutes
STANDARD_DEVIATION 3.02 • n=17 Participants • Actigraphy data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
11.97 Minutes
STANDARD_DEVIATION 3.23 • n=18 Participants • Actigraphy data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
11.60 Minutes
STANDARD_DEVIATION 3.06 • n=35 Participants • Actigraphy data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
RBANS total score (index)
88.2 units on a scale
STANDARD_DEVIATION 10 • n=17 Participants • RBANS data was not collected for the HC wavelength-1 and HC wavelength-2 arms.
96.1 units on a scale
STANDARD_DEVIATION 11.5 • n=18 Participants • RBANS data was not collected for the HC wavelength-1 and HC wavelength-2 arms.
92.53 units on a scale
STANDARD_DEVIATION 11.4 • n=35 Participants • RBANS data was not collected for the HC wavelength-1 and HC wavelength-2 arms.
PVT average speed - Run 1
3.27 responses/second
STANDARD_DEVIATION 0.41 • n=17 Participants • PVT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
3.52 responses/second
STANDARD_DEVIATION 0.35 • n=18 Participants • PVT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
3.39 responses/second
STANDARD_DEVIATION 0.39 • n=35 Participants • PVT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
PVT average speed - Run 2
3.22 responses/second
STANDARD_DEVIATION 0.51 • n=17 Participants • PVT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
3.45 responses/second
STANDARD_DEVIATION 0.42 • n=18 Participants • PVT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
3.33 responses/second
STANDARD_DEVIATION 0.48 • n=35 Participants • PVT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
PVT average speed - Run 3
3.17 responses/second
STANDARD_DEVIATION 0.43 • n=17 Participants • PVT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
3.50 responses/second
STANDARD_DEVIATION 0.59 • n=18 Participants • PVT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
3.33 responses/second
STANDARD_DEVIATION 0.53 • n=35 Participants • PVT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
ANAM Code Substitution Learning - thruput score
46.78 correct responses/minute
STANDARD_DEVIATION 14.74 • n=17 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
55.88 correct responses/minute
STANDARD_DEVIATION 12.39 • n=18 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
51.20 correct responses/minute
STANDARD_DEVIATION 13.79 • n=35 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
ANAM Procedural Reaction Time - thruput score
86.83 correct responses/minute
STANDARD_DEVIATION 19.55 • n=17 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
97.06 correct responses/minute
STANDARD_DEVIATION 19.41 • n=18 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
95.26 correct responses/minute
STANDARD_DEVIATION 17.98 • n=35 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
ANAM Mathematical Processing - thruput score
17.89 correct responses/minute
STANDARD_DEVIATION 8.44 • n=17 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
21.18 correct responses/minute
STANDARD_DEVIATION 7.38 • n=18 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
19.49 correct responses/minute
STANDARD_DEVIATION 7.89 • n=35 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
ANAM Matching to Sample - thruput score
29.5 correct responses/minute
STANDARD_DEVIATION 8.05 • n=17 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
33.29 correct responses/minute
STANDARD_DEVIATION 11.55 • n=18 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
31.34 correct responses/minute
STANDARD_DEVIATION 9.86 • n=35 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
ANAM Code Substitution delay - thruput score
41.06 correct responses/minute
STANDARD_DEVIATION 13.11 • n=17 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
52.88 correct responses/minute
STANDARD_DEVIATION 8.72 • n=18 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
46.8 correct responses/minute
STANDARD_DEVIATION 11.96 • n=35 Participants • ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
ESS total score
8.72 units on a scale
STANDARD_DEVIATION 3.32 • n=17 Participants • ESS data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
8.18 units on a scale
STANDARD_DEVIATION 3.28 • n=18 Participants • ESS data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
8.46 units on a scale
STANDARD_DEVIATION 3.27 • n=35 Participants • ESS data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
FOSQ Total Score
17.10 units on a scale
STANDARD_DEVIATION 2.18 • n=17 Participants • FOSQ data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
15.37 units on a scale
STANDARD_DEVIATION 3.82 • n=18 Participants • FOSQ data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.
14.06 units on a scale
STANDARD_DEVIATION 10.86 • n=35 Participants • FOSQ data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

PRIMARY outcome

Timeframe: Post 6-week intervention

Population: The PSQI was not administered to the HC wavelength-2 and HC wavelength-1 arms of this study.

The Pittsburgh Sleep Quality Index (PSQI) subscale measurement that was used is overall sleep quality, which is derived from question 6 on the assessment and uses a Likert scale of 0 to 3. A score of 0 represents "very good" sleep quality (better outcome), while a measurement of 3 represents "very bad" sleep quality (worse outcome).

Outcome measures

Outcome measures
Measure
mTBI Wavelength-2 Bright Light
n=18 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
mTBI Wavelength-1 Bright Light
n=17 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
Sleep Quality - Pittsburgh Sleep Quality Index (PSQI)
1.28 score on a scale
Standard Deviation .67
1.35 score on a scale
Standard Deviation .7

PRIMARY outcome

Timeframe: Post 6-week intervention

Population: Actigraphy data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

Sleep Efficiency is the overall percentage of time that the participant was scored as sleeping during their night of sleep (range: 0-100%). Higher percentages suggest higher sleep quality and a better outcome.

Outcome measures

Outcome measures
Measure
mTBI Wavelength-2 Bright Light
n=18 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
mTBI Wavelength-1 Bright Light
n=17 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
Sleep Quality - Actigraphy Sleep Efficiency
82.57 percentage of time asleep
Standard Deviation 4.2
83.43 percentage of time asleep
Standard Deviation 5.11

PRIMARY outcome

Timeframe: Post 6-week intervention

Population: Actigraphy data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

Wake After Sleep Onset (WASO) is how many minutes the participant, during their night of sleep, was determined to be awake after their sleep onset. Sleep onset is defined as a state of at least 2 minutes of uninterrupted sleep. Higher values indicate a worse outcome (range: 1-125 minutes).

Outcome measures

Outcome measures
Measure
mTBI Wavelength-2 Bright Light
n=18 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
mTBI Wavelength-1 Bright Light
n=17 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
Sleep Quality - Actigraphy Wake After Sleep Onset
11.66 minutes
Standard Deviation 2.91
10.4 minutes
Standard Deviation 3.32

PRIMARY outcome

Timeframe: Post 6-week intervention

Population: Data was collected for this measure but was unable to be analyzed due to issues extracting the data from the computer it was stored on. In addition, MSIT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study 6-weeks after the inital visit.

Neural activation during functional magnetic resonance imaging (fMRI) measuring executive functioning using the MSIT.

Outcome measures

Outcome data not reported

PRIMARY outcome

Timeframe: Post 6-week intervention

Population: ANAM data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

The Automated Neuropsychological Assessment Metrics (ANAM) is a neuropsychological battery that uses individual tests to measure cognitive efficiency in areas including attention, concentration, reaction time, memory, processing speed, and decision making. Subscale scores are put in terms of a throughput score, which is calculated to be a ratio of correct responses per minute, as a way to measure cognitive efficiency in the participant; as such, the units for the throughput scores would be in terms of correct responses/minute. Higher throughput scores indicate increased levels of cognitive efficiency in the relevant subscale. The throughput score ranges for the ANAM subscales are: code substitution learning: 0-147 responses per minute procedural reaction time: 0-151 responses per minute mathematical processing: 0-145 responses per minute matching to sample: 0-97 responses per minute code substitution delayed: 0-155 responses per minute

Outcome measures

Outcome measures
Measure
mTBI Wavelength-2 Bright Light
n=18 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
mTBI Wavelength-1 Bright Light
n=17 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
Performance on Neuropsychological Assessment - Automated Neuropsychological Assessment Metrics
ANAM Code substitution learning -thruput score
51.3 correct responses/minute
Standard Deviation 15.8
60.3 correct responses/minute
Standard Deviation 10.8
Performance on Neuropsychological Assessment - Automated Neuropsychological Assessment Metrics
ANAM Procedural Reaction Time - thruput score
89.8 correct responses/minute
Standard Deviation 19.5
101.3 correct responses/minute
Standard Deviation 17.9
Performance on Neuropsychological Assessment - Automated Neuropsychological Assessment Metrics
ANAM Mathematical Processing - thruput score
18 correct responses/minute
Standard Deviation 8.5
22.1 correct responses/minute
Standard Deviation 8.2
Performance on Neuropsychological Assessment - Automated Neuropsychological Assessment Metrics
ANAM Matching to Sample - thruput score
30.5 correct responses/minute
Standard Deviation 10.1
33 correct responses/minute
Standard Deviation 12.2
Performance on Neuropsychological Assessment - Automated Neuropsychological Assessment Metrics
ANAM Code substitution delay-thruput score
43.3 correct responses/minute
Standard Deviation 14.2
56.2 correct responses/minute
Standard Deviation 8.9

PRIMARY outcome

Timeframe: Post 6-week intervention

Population: RBANs data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) uses all of its subscales to calculate the RBANS total score (index). To obtain the RBANS total score (index), the raw scores of the subtests must first be computed into index scores for their relevant subscale (different subtest raw scores feed into specific subscales) using RBANS specific tables that have scaled scores embedded and are normed for the age of the participant. The index scores of each subscale are then summed together to get the Sum of Index Scores, which has a possible range of 200-800. Once the Sum of Index Scores is found, the total score (index) is then found using another RBANS specific table with scaled scores embedded within it. The total score (index) has a possible range of 40-160, with a higher total score (index) is related to a better outcome.

Outcome measures

Outcome measures
Measure
mTBI Wavelength-2 Bright Light
n=18 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
mTBI Wavelength-1 Bright Light
n=17 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
Performance on Neuropsychological Assessment - Repeatable Battery for the Assessment of Neuropsychological Status
88.5 units on a scale
Standard Deviation 10.7
97.6 units on a scale
Standard Deviation 12.2

PRIMARY outcome

Timeframe: Post 6-week intervention

Population: PVT data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study 6-weeks after the initial visit.

The Psychomotor Vigilance Task (PVT) is a task that tests alertness by having the participant press a button every time they see a stimulus image appear on a screen. This image is presented at random 2-10 second intervals throughout the entirety of the task. The reaction time (RT) is one of the PVT measurements and is the time, measured in milliseconds, that it takes for the participant to view the stimulus image and then press the button, confirming that they have indeed viewed the stimulus image at that time. The PVT measures speed using the following equation: 1/RT \* 1000. The PVT measurement used here is average speed, so all the calculated speeds were then averaged over the entire trial period to obtain the final value for that trial at that time point (post-tx 1,2,3). Since the PVT is a timed measurement of reaction times, lower scores are considered 'better' or indicate an increased level of vigilance.

Outcome measures

Outcome measures
Measure
mTBI Wavelength-2 Bright Light
n=18 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
mTBI Wavelength-1 Bright Light
n=17 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
Performance on Neuropsychological Assessment - Psychomotor Vigilance Task
PVT average speed - Run 3 - post-tx
3.3 responses/minute
Standard Deviation 0.6
3.4 responses/minute
Standard Deviation 0.5
Performance on Neuropsychological Assessment - Psychomotor Vigilance Task
PVT average speed - Run 1 - post-tx
3.3 responses/minute
Standard Deviation 0.4
3.4 responses/minute
Standard Deviation 0.3
Performance on Neuropsychological Assessment - Psychomotor Vigilance Task
PVT average speed - Run 2 - post-tx
3.3 responses/minute
Standard Deviation 0.7
3.4 responses/minute
Standard Deviation 0.4

PRIMARY outcome

Timeframe: Post 6-week intervention

Population: ESS data was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

The Epworth Sleepiness Scale (ESS) is an 8-item questionnaire that characterizes the likelihood of the participant 'dozing off' during typical daily activities over their last 2 weeks, and uses a 0-3 point Likert scale, where 0 corresponds to "Would never doze" and 3 corresponds to having a "High chance of dozing" during the activity in question. The ESS score is calculated by adding up all the scores for each question, which means that the ESS score has a range of 0-24, while a higher score indicates that the participant had more issues with daytime sleepiness (worse outcome).

Outcome measures

Outcome measures
Measure
mTBI Wavelength-2 Bright Light
n=18 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
mTBI Wavelength-1 Bright Light
n=17 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
Daytime Sleepiness - Epworth Sleepiness Scale
9.33 units on a scale
Standard Deviation 3.74
6.82 units on a scale
Standard Deviation 3.11

PRIMARY outcome

Timeframe: Post 6-week intervention

Population: FOSQ was not collected for the HC wavelength-2 and HC wavelength-1 arms of this study.

The Functional Outcome of Sleep Questionnaire (FOSQ) questions 1-26 use a 1-4 (ordinal) likert (1 = "No difficulty" with sleepiness, 4 = "Yes, extreme difficulty" with sleepiness) and the participant also has the option of putting 0 = "I don't do this activity for other reasons". FOSQ questions 27-30 use a 1-4 Likert scale where 1 = "Very low" in terms of characterizing the level that sleepiness affects different aspects of their intimate romantic relations, while a 4 = "High" amount of impact on their intimate romantic relations. The FOSQ total score measurement is determined by calculating the mean of all 5 subscale scores and then multiplying that value by 5 (range: 0-24). A higher score indicates that the participant had more issues with daytime sleepiness.

Outcome measures

Outcome measures
Measure
mTBI Wavelength-2 Bright Light
n=18 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
mTBI Wavelength-1 Bright Light
n=17 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
Daytime Sleepiness - Functional Outcome of Sleep Questionnaire
16.28 units on a scale
Standard Deviation 1.88
17.33 units on a scale
Standard Deviation 2.39

PRIMARY outcome

Timeframe: Post 6-week intervention

Population: The RPCSQ was not administered to the HC wavelength-2 and HC wavelength-1 arms of this study.

The Rivermead Post-Concussion Symptoms Questionnaire (RPCSQ) will be used to assess post-concussive symptoms related to sleep. All questions on the RPCSQ use a 0 to 4 Likert scale concerning the severity of experiencing differing symptoms, where 0 = "not experienced" and 4 = "severe problem". As such, having a higher score is indicative that the participant is having more serious sleep issues related to their head injury. The RPCSQ subscale measurements that were used below are: RPQ3, which is the summed scores from the first 3 questions on the form, with the subscale total ranging from 0-12, and RPQ13, which is the summed scores from questions 4 to 16 on the form, with the subscale total ranging from 0-52. The RPQ3 subscale is associated with earlier symptom clusters of post-concussive symptoms as they relate to sleep disturbances, while the RPQ13 subscale is associated with later symptom clusters of post-concussive symptoms as they relate to sleep disturbances.

Outcome measures

Outcome measures
Measure
mTBI Wavelength-2 Bright Light
n=18 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-2 bright light: 6 weeks of daily light exposure, 30 minutes per morning
mTBI Wavelength-1 Bright Light
n=17 Participants
30 minutes daily light exposure for 6 weeks mTBI wavelength-1 bright light: 6 weeks of daily light exposure, 30 minutes per morning
Post-Concussive Symptoms (Rivermead Post-Concussion Symptoms Questionnaire)
RPQ3
3 score on a scale
Standard Deviation 2.4
2.7 score on a scale
Standard Deviation 2.7
Post-Concussive Symptoms (Rivermead Post-Concussion Symptoms Questionnaire)
RPQ13
12.8 score on a scale
Standard Deviation 11.1
11.1 score on a scale
Standard Deviation 8.3

Adverse Events

mTBI Wavelength-1 Bright Light

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

mTBI Wavelength-2 Bright Light

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

HC Wavelength-1 Bright Light

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

HC Wavelength-2 Bright Light

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. William "Scott" Killgore

University of Arizona

Phone: (520) 621-0605

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place