The Effect of Transcranial Direct Current Stimulation (tDCS) on Depression in PD

Study Overview
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Brief Summary
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Depression is common in Parkinson's disease (PD), but the effective treatment is not established yet. tDCS is a non-invasive brain stimulation to modulate brain function. The tDCS on the depression in general population were already conducted, but not in PD. This study is to know whether transcranial direct current stimulation (tDCS) is effective for the treatment of depression in PD. Participant will be asked to visit three consecutive days for the non-invasive stimulation.

Official Title
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The Effect of Transcranial Direct Current Stimulation (tDCS) on Depression in Parkinson's Disease

Conditions
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Parkinson's Disease

Intervention / Treatment
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* Device: transcranial direct current stimulation (tDCS)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: UK Parkinson's disease brain bank criteria more than 19 years old Able to provide consent for the protocol Depression (based on DSM-IV criteria) Exclusion Criteria: Dementia Unpredictable symptom fluctuations Contraindication to tDCS (i) irritations, cuts, lesions in the brain (ii) any preexisting unstable medical conditions, or conditions that may increase the risk of stimulation such as uncontrolled epilepsy (iii) history of severe cranial trauma with alteration of the cranial anatomy or metallic intracranial implants (iv) history of seizure Subjects without the capacity to give informed consent If participation in the study would, in the opinion of the investigators, cause undue risk or stress for reasons such as excessive fatigue, general frailty, or excessive apprehension

Ages Eligible for Study
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Minimum Age: 19 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Randomized, Parallel, Sham-controlled, single-blinded study
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Real tDCS<br>Constant weak electric currents through scalp via two electrodes will be delivered. Current intensity: 2mA, 20min/day | Device: transcranial direct current stimulation (tDCS)<br>* tDCS is one of non-invasive brain stimulation. Constant, low current is delivered to the specific brain areas to change brain plasticity.<br>|
| Sham Comparator: Sham tDCS<br>a 1 mA current, for 30 s giving an initial sensation of tDCS while minimizing stimulatory effects Ramp up and ramp down was over 10 s. (Ref. Loo CK et al., Br J Psychiatry 2012;200:52-9) | Device: transcranial direct current stimulation (tDCS)<br>* tDCS is one of non-invasive brain stimulation. Constant, low current is delivered to the specific brain areas to change brain plasticity.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| BDI score | The changes of Beck depression inventory after tDCS | (1) before the1st visit (within one month) (2) right after the 3rd tDCS (3) within one months after the 3rd tDCS | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| HDRS score | The changes of Hamilton Depression Rating Scale after tDCS | (1) before the 1st visit (within one month) (2) right after 3rd tDCS, within 24 hours (3) within one months after the 3rd tDCS | 
| MADRS score | The changes of Mongomery-Asberg Depression Rating Scale after tDCS | (1) before the 1st visit (within one month) (2) right after the 3rd tDCS, within 24 hours (3) within one months after 3rd tDCS | 
| resting state functional MRI | The changes of resting state functional MRI after tDCS | (1) before the 1st visit (within one month) (2) after the 3rd tDCS, within 24 hours (on the same day as the 3rd tDCS) |