Trial Outcomes & Findings for The Effect of Light Therapy on Chronic Pain (NCT NCT03677206)

Last Updated: 2025-11-18

Results Overview

Change in the intensity of chronic pain as measured by the Numerical Pain Scale (NPS). The NPS has a value ranging from 0 to 10 out of a maximum of 10. 0 means no pain. 10 means the most severe pain.

Recruitment status

ACTIVE_NOT_RECRUITING

Study phase

Target enrollment

55 participants

Primary outcome timeframe

baseline and 10 - 22 weeks, depending on study arm

Results posted on

2025-11-18

Participant Flow

Participant milestones

Participant milestones
Measure	Exposure to White LED Light Crossed Over to Green LED. Subjects will exposed to white light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks Exposure to white LED light: Participants will be exposed to white LED strip lights in a dark room for 2 hours a day.
Overall Study STARTED	55
Overall Study COMPLETED	53
Overall Study NOT COMPLETED	2

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

The Effect of Light Therapy on Chronic Pain

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Exposure to White LED Light and Crossover to Green LED Light. n=55 Participants Subjects will exposed to white light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks Exposure to white LED light: Participants will be exposed to white LED strip lights in a dark room for 2 hours a day. Subjects will exposed to green light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks. Exposure to green LED light: Participants will be exposed to green LED strip lights in a dark room for 2 hours a day. Subject will be exposed to white light (sham) for 10 weeks, then have a wash out period for 2 weeks, then exposed to green light (experimental) for 10 weeks. Exposure to green LED light: Participants will be exposed to green LED strip lights in a dark room for 2 hours a day. Exposure to white LED light: Participants will be exposed to white LED strip lights in a dark room for 2 hours a day.
Age, Categorical <=18 years	0 Participants n=202 Participants
Age, Categorical Between 18 and 65 years	50 Participants n=202 Participants
Age, Categorical >=65 years	5 Participants n=202 Participants
Age, Continuous	52.7 years STANDARD_DEVIATION 2.95 • n=202 Participants
Sex: Female, Male Female	53 Participants n=202 Participants
Sex: Female, Male Male	2 Participants n=202 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	16 Participants n=202 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	39 Participants n=202 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=202 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=202 Participants
Race (NIH/OMB) Asian	0 Participants n=202 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=202 Participants
Race (NIH/OMB) Black or African American	0 Participants n=202 Participants
Race (NIH/OMB) White	55 Participants n=202 Participants
Race (NIH/OMB) More than one race	0 Participants n=202 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=202 Participants
Region of Enrollment United States	55 participants n=202 Participants

PRIMARY outcome

Timeframe: baseline and 10 - 22 weeks, depending on study arm

Population: Adult patients with chronic pain

Change in the intensity of chronic pain as measured by the Numerical Pain Scale (NPS). The NPS has a value ranging from 0 to 10 out of a maximum of 10. 0 means no pain. 10 means the most severe pain.

Outcome measures

Outcome measures
Measure	Exposure to White LED Light n=55 Participants Subjects will be exposed to white light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks	Green LED Light Exposure n=55 Participants Subjects will be exposed to green light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks
For Chronic Pain	0.45 score on a scale Standard Deviation 0.2	3.7 score on a scale Standard Deviation 0.4

SECONDARY outcome

Timeframe: baseline and 10 - 22 weeks, depending on study arm

Population: patients with fibromyalgia

Change in Fibromyalgia Impact Questionnaire (FIQ) total score. The FIQ is a validated, self-reported measure assessing physical functioning, work status, depression, anxiety, sleep, pain, stiffness, fatigue, and well-being over the past week. Scores range from 0 to 100, with higher scores indicating greater impairment.

Outcome measures

Outcome measures
Measure	Exposure to White LED Light n=55 Participants Subjects will be exposed to white light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks	Green LED Light Exposure n=55 Participants Subjects will be exposed to green light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks
Fibromyalgia Impact Questionnaire	10.43 score on a scale Standard Deviation 3.46	28.92 score on a scale Standard Deviation 4.32

SECONDARY outcome

Timeframe: baseline and 10 - 22 weeks, depending on study arm

Change in Headache Impact Test-6 (HIT-6) total score from baseline to 10-22 weeks. The HIT-6 is a 6-item questionnaire designed to assess the impact of headaches on daily life, including pain severity, disability, and emotional effects over the past 4 weeks. Scores range from 36 to 78, where 36-49 indicates little or no impact, 50-55 indicates some impact, 56-59 reflects substantial impact, and 60-78 indicates severe impact requiring intervention. A higher score indicates greater headache impact.

Outcome measures

Outcome measures
Measure	Exposure to White LED Light n=55 Participants Subjects will be exposed to white light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks	Green LED Light Exposure n=55 Participants Subjects will be exposed to green light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks
Headache Impact Test-6	1.14 score on a scale Standard Deviation 1.3	12.85 score on a scale Standard Deviation 1.6

SECONDARY outcome

Timeframe: baseline and 10 - 22 weeks, depending on study arm

Change in health-related quality of life as measured by the EQ-5D-5L. The EQ-5D-5L is a standardized, patient-reported outcome measure that assesses health-related quality of life across five dimensions (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression), each rated on a 5-level scale (no problems to extreme problems). The score is calculated using a country-specific value set to produce a single index value ranging from -0.594 (worse than death) to 1.0 (perfect health), where higher scores indicate better health status.

Outcome measures

Outcome measures
Measure	Exposure to White LED Light n=55 Participants Subjects will be exposed to white light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks	Green LED Light Exposure n=55 Participants Subjects will be exposed to green light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks
EQ-5D-5L	0.13 score on a scale Standard Deviation 0.03	0.28 score on a scale Standard Deviation 0.04

Adverse Events

Exposure to White LED Light

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Exposure to Green LED 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. Mohab Ibrahim

University of Arizona

Phone: (520) 626-7221

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place