Bright Light Therapy for Non-motor Symptoms in Parkinson's Disease

November 4, 2025 updated by: Aleksandar Videnovic, MD, Massachusetts General Hospital

Bright Light Modulation of Non-motor Symptoms in Parkinson's Disease

Disruption of sleep and alertness is one of the most disabling non-motor symptoms of Parkinson's disease (PD). Mechanisms leading to impaired sleep and alertness in PD are not well understood, and treatment options remain limited. The proposed research will examine markers of the circadian system, sleepiness and sleep quality in PD patients. Further, the project will examine effects of bright light exposure on circadin function, sleep and alertness in PD.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

65

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Massachusetts
      • Boston, Massachusetts, United States, 02114
        • Massachusetts General Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

40 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion criteria:

  1. Diagnosis of idiopathic PD as defined by the United Kingdom PD Society Brain Bank Criteria
  2. PD Hoehn and Yahr stage 2-4
  3. Pittsburgh Sleep Quality Index (PSQI) score ≥ 5
  4. Treatment with levodopa and/or dopamine agonist; adjunctive PD medications will be allowed
  5. Stable dose of PD medications for at least 4 weeks prior to the study screening.

Exclusion criteria:

  1. Atypical or secondary forms of parkinsonism
  2. Co-existent significant sleep apnea (as assessed by polysomnography- derived apnea/hypopnea index ≥15 events/hr of sleep)
  3. Co-existent restless legs syndrome (RLS), as assessed by the International Classification of Sleep Disorders (ICDS) diagnostic criteria for RLS
  4. Cognitive impairment as determined by the Mini-Mental State Examination (MMSE) score of ≤ 26
  5. Presence of depression defined as the Beck Depression Inventory (BDI) score >14
  6. Untreated hallucinations or psychosis (drug-induced or spontaneous)
  7. Use of hypno-sedative drugs for sleep or stimulants; participants will be allowed to taper these drugs and will become eligible 4 weeks after the taper is completed
  8. Use of Selective Serotonin Reuptake Inhibitors (SSRIs) / Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs) antidepressants, unless the participant has been on a stable dose for at least 3 months prior to the screening
  9. Use of medications known to affect melatonin secretion, such as lithium, alpha- and beta-adrenergic antagonists
  10. Shift work, currently or within the prior 3 months
  11. Travel through ≥ 2 time zones within 60 days prior to study screening
  12. Hematocrit <32 mm3
  13. Pre-existing glaucoma/retinal disease contraindicated for light therapy (LT)
  14. Dense cataracts
  15. Use of medications known to photosensitize retinal tissue (phenothiazines, chloroquine, amiodarone, St. John's Wort)
  16. Unstable/serious medical illness.
  17. Pregnancy

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Bright light therapy
Participants will be treated twice daily with bright light therapy.
Device: Light Therapy Device
Active Comparator: Dim-Red light therapy
Participants will be treated twice daily with dim-red light therapy.
Device: Light Therapy Device

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Parkinson's Disease Sleep Scale (PDSS-2) score to measure sleep quality
Time Frame: 8 weeks
8 weeks

Secondary Outcome Measures

Outcome Measure
Time Frame
Epworth Sleepiness Scale (ESS) score to measure daytime sleepiness
Time Frame: 8 weeks
8 weeks
Non-Motor Symptoms Assessment Scale for Parkinson's Disease (NMSS) score to measure the severity and frequency of non-motor symptoms
Time Frame: 8 weeks
8 weeks
Plasma melatonin levels collected through blood samples to measure melatonin amplitude and circadian regulation
Time Frame: 8 weeks
8 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Massachusetts General Hospital

Investigators

  • Principal Investigator: Aleksandar Videnovic, MD, MSc, Massachusetts General Hospital

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

December 1, 2016

Primary Completion (Actual)

July 5, 2022

Study Completion (Estimated)

November 1, 2026

Study Registration Dates

First Submitted

September 15, 2016

First Submitted That Met QC Criteria

September 20, 2016

First Posted (Estimated)

September 21, 2016

Study Record Updates

Last Update Posted (Estimated)

November 5, 2025

Last Update Submitted That Met QC Criteria

November 4, 2025

Last Verified

November 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 2016P001775

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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