This clinical trial investigates the effects of bright light therapy on motor symptoms and sleep disorders in patients with Parkinson's disease. The study is conducted at the Second Affiliated Hospital of Soochow University in Suzhou, China.
Bright light therapy is a non-invasive intervention that uses controlled exposure to bright artificial light to help regulate circadian rhythms. In Parkinson's disease, circadian rhythm disturbances are common and contribute to sleep disorders, mood disturbances, and potentially motor symptom fluctuations.
| Parameter | Value |
|---|---|
| NCT Number | NCT06129942 |
| Title | Light Therapy in Parkinson's Disease |
| Status | Recruiting |
| Phase | Not Applicable |
| Sponsor | Second Affiliated Hospital of Soochow University |
| Principal Investigator | Chun-Feng Liu, PhD |
| Enrollment | 50 participants (estimated) |
| Start Date | September 1, 2021 |
| Primary Completion | May 16, 2026 (estimated) |
| Location | Suzhou, Jiangsu, China |
| Design Element | Details |
|---|---|
| Type | Interventional |
| Allocation | Randomized |
| Intervention Model | Crossover |
| Primary Purpose | Treatment |
| Masking | Double-blind (Participant, Investigator) |
Patients receive bright light therapy using a light box operating at 10,000 lux intensity:
The light box uses a spectrally transparent prism diffuser that blocks ultraviolet rays while preserving light quality.
Patients receive placebo treatment using a device operating at 300 lux intensity:
Parkinson's disease is associated with significant circadian rhythm disturbances:
Bright light therapy exerts its effects through:
Clinical evidence suggests bright light therapy may benefit PD patients through:
Sleep-related
Visual
Cognitive
Psychiatric
| Outcome | Assessment Timing |
|---|---|
| Total Sleep Time (TST) by polysomnography | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| Sleep Efficiency by polysomnography | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| REM Sleep Without Atonia (RWA) by PSG | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| Sleep Onset Latency by PSG | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| Periodic Limb Movement during Sleep (PLMS) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| Sleep Stage Duration and Percentage | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| Slow Wave Activity (SWA) and Slow Wave Energy (SWE) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| Outcome | Assessment Timing |
|---|---|
| MDS-UPDRS Score | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| Hoehn-Yahr Scale | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| PDSS-2 (Parkinson's Disease Sleep Scale-2) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| PSQI (Pittsburgh Sleep Quality Index) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| RBDQ-HK (REM Sleep Behavior Disorder Questionnaire-Hong Kong) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| ESS (Epworth Sleepiness Scale) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| MEQ (Morningness-Eveningness Questionnaire) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| HAMA (Hamilton Anxiety Scale) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| HAMD-24 (Hamilton Depression Scale-24) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| MoCA (Montreal Cognitive Assessment) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| NMSQ (Non-Motor Symptoms Questionnaire) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| PDQ-39 (Parkinson's Disease Questionnaire-39) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| FSS (Fatigue Severity Scale) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| EEG (Electroencephalogram) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| Melatonin rhythmic level (serum and saliva) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| Cortisol rhythmic level (serum and saliva) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
| fMRI (functional Magnetic Resonance Imaging) | Visit 1 (baseline), Visit 2 (Week 4), Visit 3 (Week 8), Visit 4 (Week 12) |
Sleep disturbances are among the most common non-motor symptoms in Parkinson's disease:
Current PD therapies primarily target:
However, these do not adequately address circadian rhythm disturbances.
Light therapy offers several advantages:
| Study | Intensity | Duration | Key Findings |
|---|---|---|---|
| This trial (NCT06129942) | 10,000 lux | 1 month | PSG sleep metrics, MDS-UPDRS |
| Videnovic et al. 2017 | 10,000 lux | 2 weeks | Improved sleep quality, daytime sleepiness |
| Rutten et al. 2019 | 10,000 lux | 6 weeks | Improved depression scores |
| Paus et al. 2007 | 5,000 lux | 4 weeks | Improved motor scores |