Using bright light therapy to improve sleep and mood in Parkinson's disease

Randomized Placebo- and Active-controlled Trial for Assessing the Efficacy of Bright Light Therapy for Sleep and Mood Symptoms in Patients With Parkinson's Disease

NA · Chinese University of Hong Kong · NCT05524961

This study is testing if bright light therapy can help people with Parkinson's disease feel less sleepy during the day and improve their mood.

Quick facts

PhaseNA
Study typeInterventional
Enrollment69 (estimated)
Ages18 Years and up
SexAll
SponsorChinese University of Hong Kong (other)
Locations1 site (Hong Kong)
Trial IDNCT05524961 on ClinicalTrials.gov

What this trial studies

This trial evaluates the effectiveness of bright light therapy (BLT) in reducing excessive daytime sleepiness and improving mood symptoms in patients with Parkinson's disease. Participants will be randomly assigned to receive either timed-BLT or an active control using an inactivated negative ion generator. The study also aims to assess the impact of BLT on other non-motor symptoms such as depression and fatigue, as well as overall quality of life. Additional comparisons will be made between different placebo conditions to ensure robust results.

Who should consider this trial

Good fit: Ideal candidates are individuals diagnosed with idiopathic Parkinson's disease who experience excessive daytime sleepiness.

Not a fit: Patients with a history of severe psychiatric conditions or cognitive impairment may not benefit from this study.

Why it matters

Potential benefit: If successful, this therapy could significantly improve sleep quality and mood for patients with Parkinson's disease.

How similar studies have performed: Previous studies have shown promising results for light therapy in managing non-motor symptoms in Parkinson's disease, suggesting potential for success in this approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Idiopathic Parkinson's disease diagnosed by neurologist according to the UK Parkinson's Disease Society Brain Bank clinical diagnostic criteria
2. Capable to give informed consent
3. Maintained on stable dose of medications for Parkinson's disease/psychotropic drugs for at least four weeks prior to entry of the study
4. Score 14 or more on the Epworth Sleepiness Scale

Exclusion Criteria:

1. A current or past history of manic or hypomanic episode, schizophrenia, mental retardation, or substance use disorder. (Subjects with depression or anxiety disorders will not be excluded)
2. Unstable medical or psychiatric condition
3. Presence of substantial suicidal risk as judged by the clinician and/or screening instruments
4. Presence of active psychotic symptoms that might impair the ability to consent or validity of the interview
5. Cognitive impairment with score of 19 or below by the Hong Kong version of Montreal Cognitive Assessment (HK-MoCA)
6. Contraindication to bright light therapy: history of light induced migraine. Epilepsy, current use of photosensitizing medications, presence of eye disease, e.g. retinal disease, severe cataract, glaucoma and blindness
7. Significant medical condition/ hearing impairment/ speech deficit lead to incapability in completing clinical interview
8. Regular shift worker or trans-meridian flight in the past three months
9. Enrolment in another clinical trial of an investigational medicinal product or device
10. Subjects who are on exogenous melatonin
11. Patients with deep brain stimulation (DBS) implant
12. Patients with known sleep disorders, eg. untreated severe sleep apnea, restless leg syndrome

Where this trial is running

Hong Kong

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Parkinson Disease, Parkinson disease, Light therapy, Daytime sleepiness, Non-motor symptom

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.