Effects of Combined Blue and Red Home-Based Light Therapy on Sleep in Adults With Self-Reported Sleep Difficulties

NCT07465250 | Completed

• 1 other identifier: 5775
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this intervention is to learn if a combination of morning blue light and evening red light therapy can improve sleep quality in adults with subclinical sleep complaints (non-diagnosed difficulty initiating or maintaining sleep). The main questions it aims to answer are: Does combined morning blue light and evening red light therapy reduce sleep onset latency (the time it takes to fall asleep) and improve sleep efficiency? Does this light therapy intervention improve subjective alertness upon awakening? Researchers will compare each participant's objective and subjective sleep data during a 7-day baseline (habitual routine) with their data during a 7-day light therapy intervention to assess whether light therapy improves sleep and daytime alertness.

Conditions

Sleep

Keywords

light therapy; phototherapy; blue light exposure; red light exposure; sleep quality; sleep; actigraphy

Outcome Measures

Primary Outcomes (1)

• Sleep Onset Latency

  Sleep Onset Latency (SOL) is the amount of time (measured in minutes) it takes a participant to fall asleep after getting into bed. This will be measured objectively using a 24-hour wrist-worn actigraphy device. The study will compare the average SOL during the 7-day habitual baseline period (Control) to the average SOL during the 7-day light therapy intervention period (Treatment) to assess the efficacy of the dual-spectrum light exposure.

  Average of 7 days during the Control phase (Days 1-7) and average of 7 days during the Treatment phase (Days 8-14).

Secondary Outcomes (2)

• Total Sleep Time

  Average of 7 days during the Control phase (Days 1-7) and average of 7 days during the Treatment phase (Days 8-14).

• Subjective Morning Alertness

  Daily upon awakening for 15 days.

Study Arms (1)

LED Light Therapy

EXPERIMENTAL

Participants in this single-arm study follow a within-subject consecutive design. All participants complete a 7-day baseline period (Control) following their habitual routine, followed immediately by a 7-day intervention period (Treatment). The intervention consists of: Morning Exposure: 2 hours of short-wavelength blue light exposure immediately upon waking. Evening Exposure: 2 hours of long-wavelength red light exposure during the 2 hours prior to the participant's anticipated bedtime. The primary goal of this arm is to assess the impact of this dual-light protocol on objective sleep onset latency and subjective morning alertness compared to the participant's own baseline data.

Other: LED portable light therapy bulb

Interventions

LED portable light therapy bulb OTHER

Unlike studies that use only bright white light or single-wavelength blue light, this intervention combines morning short-wavelength (blue) light with evening long-wavelength (red) light. This study specifically targets individuals with "subclinical" sleep complaints-those with a Pittsburgh Sleep Quality Index (PSQI) score \>1-rather than patients already diagnosed with clinical insomnia or Circadian Rhythm Sleep Disorders. The protocol requires a precise 4-hour daily total exposure (2 hours in the morning and 2 hours in the evening), which is more intensive than many standard 30-minute light box protocols. This is an at-home intervention where participants use portable lamp mounting options to integrate 4 hours of therapy into their regular daily activities, rather than receiving treatment in a controlled laboratory setting.

Also known as: light therapy, Blue light, red light

LED Light Therapy

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults age 18 and older
• Subclinical complaints of disrupted sleep or poor sleep quality
• a score of 3 or greater on the Pittsburgh Sleep Quality Index (PSQI)

You may not qualify if:

• Younger than 18 years of age,
• Complaints of disrupted or poor sleep with a PSQI score of less than 2
• Previously diagnosed clinical sleep disorder, such as insomnia or Circadian Rhythm Sleep Disorder (CRSD)
• Employment in evening, night, or rotating shifts
• Engagement in irregular sleep patterns that are not aligned with the biological night
• Inability to comply with the study protocol and at-home study requirements

Sponsors & Collaborators

• Colorado State University: lead

Study Sites (1)

Colorado State University

Fort Collins, Colorado, 80523, United States

Location

Related Links

• Josiane Broussard's Bibliography

MeSH Terms

Conditions

Sleep Initiation and Maintenance Disorders

Interventions

Phototherapy; Blue Light; Red Light

Condition Hierarchy (Ancestors)

Sleep Disorders, Intrinsic; Dyssomnias; Sleep Wake Disorders; Nervous System Diseases; Mental Disorders

Intervention Hierarchy (Ancestors)

Therapeutics; Light; Electromagnetic Radiation; Electromagnetic Phenomena; Magnetic Phenomena; Physical Phenomena; Optical Phenomena; Radiation; Radiation, Nonionizing

Study Officials

• Josiane L Broussard, PhD

  Colorado State University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Model Details: This is a within-subject, consecutive design study in which each participant serves as their own control.

Study Record Dates

• First Submitted: February 17, 2026
• First Posted: March 11, 2026
• Study Start: July 9, 2024
• Primary Completion: July 7, 2025
• Study Completion: July 7, 2025
• Last Updated: March 12, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)