Transcranial Direct Current Stimulation and the Interaction Between Chronic Pain and the Intestinal Epithelial Barrier in Patients With Chronic Inflammatory Bowel Diseases (IBD)

Study Overview
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Brief Summary
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In the study the investigators aim to test whether transcranial direct current stimulation (tDCS) induced pain reduction is in association with functional changes in the brain measured with magnetic resonance imaging (MRI) and also with a change in permeability of the intestinal epithelial barrier in patients with chronic inflammatory bowel diseases (IBD) Hypothesis: Transcranial direct current stimulation can reduce the perception of pain in patients with chronic inflammatory bowel diseases, which is in association with changes in the brain measured via MRI. Additionally, transcranial direct current stimulation and the induced pain reduction influence the permeability of the intestinal epithelial barrier

Official Title
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Transkranielle Gleichstromstimulation Und Die Interaktion Zwischen Chronischem Schmerz Und Der Intestinalen Epithelbarriere

Conditions
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Inflammatory Bowel Diseases

Intervention / Treatment
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* Device: Sham OR active Transcranial direct current stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Inflammatory bowel disease Chronic pain (more than 3 months) Pain (VAS > 3/10) Exclusion Criteria: Contraindication to transcranial direct current stimulation Contraindications to functional magnetic resonance imaging (fMRI) Pregnancy Sever internal or psychiatric condition

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Active tDCS<br>Active transcranial direct current stimulation | Device: Sham OR active Transcranial direct current stimulation<br>* Sham OR active transcranial direct current stimulation over the motor cortex<br>* Other names: Sham OR active tDCS;|
| Sham Comparator: Sham tDCS<br>Sham transcranial direct current stimulation | Device: Sham OR active Transcranial direct current stimulation<br>* Sham OR active transcranial direct current stimulation over the motor cortex<br>* Other names: Sham OR active tDCS;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Functional changes in the brain measured with cerebral MRI | Exploratory analyses of resting-state fMRI | 6 weeks | 
| Structural changes in the brain measured with cerebral MRI | Exploratory analyses of MRI with respect to DTI (diffusions tensor imaging) and VBM (voxel based morphometry) | 6 weeks | 
| Functional and/or structural changes in the Intestinal Epithelial Barrier measured with endoscopy of the rectum with sample-taking |  | 6 weeks | 
| Changes in pain measured with visual analogue scale | VAS , scale from 0-10 | 6 weeks | 
| Changes in perception of pain measured with an algometer (pain pressure threshold) | continuous scale form 0 kg | 6 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in questionnaire quality of life | questionnaire quality of life analyses daily activities, scale running from 32 points (worse outcome) to 224 points (best outcome) | 6 weeks | 
| Changes in functional symptoms using IBS-SSS | IBS-SSS: irritable bowel syndrome - severity score system , questionnaire analyses functional symptoms, score running from 0 (best outcome) until 600 points (worst outcome) | 6 weeks | 
| Changes in activity indices using HWI questionnaire or SCCAI questionnaire | HWI: Harvey-Bradshaw-Index, SCCAI: Simple Clinical Colitis Activity Index, scale: points: 0-20 points (low points are best outcome, high points are worst outcome) | 6 weeks | 
| Changes in pain catastrophizing scale questionnaire | pain catastrophizing scale questionnaire analyses subjective catastrophizing due to pain, score running from 0-52 points (low points are best outcome, high points are worst outcome) | 6 weeks | 
| Changes in inflammation biomarker (blood - C-reactive protein) | unit: mg/dl | 6 weeks | 
| Changes in inflammation biomarker (stool - calprotectin) | Unit: mg/g | 6 weeks |