Parkinson's disease (PD) is characterized not only by motor symptoms but also by common and clinically significant non-motor symptoms, including constipation and sleep disturbances, which can substantially impair quality of life. The concept of the "gut-brain axis" describes bidirectional communication among the central nervous system, autonomic nervous system, enteric nervous system, and gut microbiota. Increasing evidence from animal models suggests that the gut-brain axis may play an important role in the pathophysiology and progression of PD.
Given the central role of autonomic nervous system regulation in the gut-brain axis, this study will use laser acupuncture as a safe, non-invasive form of photobiomodulation (PBM) with potential neuromodulatory effects. Based on the concept of segmental neuromodulation, laser stimulation will be applied to the thoracolumbar paraspinal regions (T10-L2) and sacral segments (S2-S4, corresponding to the Baliao points) to modulate sympathetic activity arising from T10-L2 and pelvic parasympathetic activity arising from S2-S4. This approach is intended to promote intestinal motility and defecation reflexes. Meanwhile, by modulating autonomic balance and stabilizing stress-sleep rhythms, as assessed by salivary biomarkers including salivary cortisol and salivary alpha-amylase (sAA), the intervention is expected to improve sleep quality in patients with PD.
This study is designed as a randomized, double-blind, sham-controlled clinical trial. Participants with PD who experience constipation will be recruited and undergo an 8-week intervention. The primary outcomes will assess changes in constipation symptoms using the Bristol Stool Form Scale (BSFS) and the Constipation Scoring System (CSS; Agachan Score). Secondary outcomes will assess sleep quality using the Parkinson's Disease Sleep Scale-2 (PDSS-2) and the REM Sleep Behavior Disorder Screening Questionnaire (RBDSQ). Objective salivary biomarkers, including salivary cortisol and sAA, will also be measured to investigate changes in autonomic function and their associations with improvements in clinical symptoms.
This study is expected to provide preliminary evidence regarding the potential role of segmental laser acupuncture in modulating the gut-brain axis and improving non-motor symptoms in patients with PD, thereby providing a basis for future larger-scale studies and the development of clinical care strategies.
Diagnosis of Parkinson's disease by a neurologist according to the Movement Disorder Society (MDS) clinical diagnostic criteria.
Coexisting chronic constipation meeting the Rome IV diagnostic criteria. Age ≥ 50 years.
Stable dosage of anti-Parkinson's medications for at least 4 weeks prior to study enrollment.
Ability to understand the study procedures, provide written informed consent, and comply with scheduled visits and study assessments.
Organic gastrointestinal diseases, such as gastrointestinal malignancy, intestinal obstruction, or inflammatory bowel disease.
Severe cognitive impairment, including dementia that significantly interferes with study participation, or severe psychiatric disorders that affect compliance.
Severe skin infection or open wounds at the treatment sites, including the thoracolumbar or sacral regions.
Implanted electronic medical devices, such as cardiac pacemakers or deep brain stimulation (DBS) devices, unless deemed eligible after appropriate safety evaluation.
Parallel
TI-816-3E3 Portable Laser Phototherapy Device
DeviceSegmental laser acupuncture is administered using the TI-816-3E3 Portable Laser Phototherapy Device at the T10-L2 and S2-S4 regions. The device is applied in contact mode, with a power density of 100 mW/cm² and a treatment dose of 6 J/cm² per application. Each treatment session lasts 60 seconds. Treatment is administered twice weekly for 8 weeks.
TI-816-3E3 Portable Laser Phototherapy Device - Sham (0 J/cm²)
DeviceSham segmental laser acupuncture is administered using the TI-816-3E3 Portable Laser Phototherapy Device at the T10-L2 and S2-S4 regions. The device is applied in contact mode with a power density of 0 mW/cm² and a treatment dose of 0 J/cm² per application. The sham procedure provides visible light and is designed to be identical to the active treatment in terms of device operation, treatment procedure, treatment duration, and participants' sensory experience. Each treatment session lasts 60 seconds. Treatment is administered twice weekly for 8 weeks. No therapeutic laser energy is delivered.
Change in Constipation Scoring System (CSS; Agachan score)
Change in constipation severity assessed using the Constipation Scoring System (CSS; Agachan score). The CSS consists of 8 items assessing bowel movement frequency, difficulty, sensation of incomplete evacuation, abdominal pain, time spent on the toilet, and use of assistance for bowel evacuation. Scores range from 0 to 30, with higher scores indicating more severe constipation.
Change in Bristol Stool Form Scale (BSFS) score
Change in stool form assessed using the Bristol Stool Form Scale (BSFS), which classifies stool consistency into seven types ranging from hard stool to watery stool (Type1 to Type7).
Change in Parkinson's Disease Sleep Scale-2 (PDSS-2) score
Change in sleep disturbance assessed using the Parkinson's Disease Sleep Scale-2 (PDSS-2), a disease-specific questionnaire for patients with Parkinson's disease. The PDSS-2 assesses nocturnal motor symptoms, such as difficulty turning in bed and tremor, rapid eye movement (REM)-related symptoms, and daytime sleepiness, thereby reflecting changes in overall sleep quality following the intervention. Higher scores indicate greater sleep disturbance.
REM Sleep Behavior Disorder Screening Questionnaire (RBDSQ) score
The RBDSQ is used to screen for symptoms suggestive of REM sleep behavior disorder (RBD) and to characterize baseline RBD-related features. RBDSQ results will be used for prespecified subgroup analyses to investigate whether the presence or absence of RBD affects the therapeutic efficacy of segmental laser acupuncture.
Change in salivary cortisol level
Change in salivary cortisol level as a biomarker of hypothalamic-pituitary-adrenal (HPA) axis activity and physiological stress response. Saliva samples are collected between 08:00 and 09:00 to minimize the influence of diurnal variation.
Change in salivary alpha-amylase (sAA) level
Change in salivary alpha-amylase (sAA) level as a surrogate biomarker of sympathetic nervous system activity, used to evaluate changes in autonomic nervous system activity following the intervention.
Click on the lead sponsor to view all of their trials.
This trial is not recruiting at the moment. You can still explore other options:
