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Completed

NCT Number: NCT05524961

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

This is a 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

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Key information

Conditions

Parkinson Disease Basal Ganglia Diseases Brain Diseases Central Nervous System Diseases Disorders of Excessive Somnolence Dyssomnias Mental Disorders Movement Disorders Nervous System Diseases Neurodegenerative Diseases Parkinsonian Disorders Sleep Disorders, Intrinsic Sleep Wake Disorders Synucleinopathies

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

The Chinese University of Hong Kong

Hong Kong

About this study

The primary aim of this study is to compare the efficacy of timed-BLT (BLT group) in reducing excessive daytime sleepiness in patients with Parkinson's disease, when compared to a timed-inactivated negative ion generator (active-control group).

The secondary aims of the study are to examine the effect of timed-BLT on other non-motor symptoms, including depression, fatigue; and the quality of life.

Additional analyses will be carried out to examine the efficacy of the timed-placebo as compared to the random-time placebo (placebo group).

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

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

Exclusion criteria

  • 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)
  • Unstable medical or psychiatric condition
  • Presence of substantial suicidal risk as judged by the clinician and/or screening instruments
  • Presence of active psychotic symptoms that might impair the ability to consent or validity of the interview
  • Cognitive impairment with score of 19 or below by the Hong Kong version of Montreal Cognitive Assessment (HK-MoCA)
  • 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
  • Significant medical condition/ hearing impairment/ speech deficit lead to incapability in completing clinical interview
  • Regular shift worker or trans-meridian flight in the past three months
  • Enrolment in another clinical trial of an investigational medicinal product or device
  • Subjects who are on exogenous melatonin
  • Patients with deep brain stimulation (DBS) implant
  • Patients with known sleep disorders, eg. untreated severe sleep apnea, restless leg syndrome

Treatment and study plan

Bright Light Therapy

Device

Regularly-timed exposure to 10,000lux bright light therapy for 60minutes a day for six weeks

Inactivated negative ion generator

Device

Regularly-timed exposure to an inactivated negative ion generator for 60minutes a day for six weeks

Primary outcomes

  1. Change of daytime sleepiness

    Time frame: at the end of 6-week treatment

    Change in the score of Epworth Sleepiness Scale (ESS), ESS score ranges from 0-24, higher score indicates greater sleepiness

Secondary outcomes

  1. Change of depressive symptoms

    Time frame: at the end of 6-week treatment

    Change in the score of Montgomery-Åsberg Depression Rating Scale (MADRS), MARDS ranges from 0-60, higher score indicates greater severity of depressive symptoms

  2. Change in fatigue symptoms

    Time frame: at the end of 6-week treatment

    Change in the score of Faitgue Severity Scale (FSS), FSS consists of 9 items and each as rated on a scale from 1-7, higher score indicates greater severity of fatigue

  3. Change in quality of life

    Time frame: at the end of 6-week treatment

    Change in score of Short-Form 12-item (SF-12) scale. SF-12 consists of two subscales - a mental component score (MCS-12) and a physical component score (PCS-12), a higher score indicates better quality of life. Scores range from 0 to 100, with higher scores indicating better physical and mental health functioning

Sponsors and collaborators

Lead sponsor

Chinese University of Hong Kong

Other

Registry information

Official study title

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

Important dates

Study start
2022
Primary completion
2025
Study completion
2026
First posted
Sep 1, 2022
Registry last updated
Mar 20, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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