Transcranial Direct Current Stimulation (tDCS) as Treatment Method for Pain in Fibromyalgia

The purpose of this study is to investigate Transcranial Direct Current Stimulation as treatment method for pain in fibromyalgia.

Fibromyalgia (FIM) is a chronic pain condition with high prevalence. Studies involving neuroimaging techniques have identified functional differences in cerebral pain processing in patients with FIM, as compared to healthy controls. This may support that FIM do have a functional CNS component. Transcranial Direct Current Stimulation (tDCS) is a non-invasive and safe method for inducing changes in cortical excitability. Previous studies showed that anodal stimulation of M1 may change pain perception, possibly by modulating functional anomalies in the FIM brain. The present study has two main goals: To investigate if tDCS may provide FIM patients with symptom relief due to reduction of pain. To investigate tDCS induced functional changes in the brain by using fMRI.

Pain (intensity and unpleasentness) measured with Visual Analog Scale. Repported at 3 points daily (0900hrs, 1500hrs, 2100hrs) using Short Message System (SMS) 14 days pre-treatment (baseline), during treatment 5 days, and 30 days post-treatment. Measure effect of active\sham tDCS on pain. 2 levels of group (active tDCS\ sham tDCS, 7 repeated measures: pre-treatment day 1, 2 ,3, 4, 5 - post) SMS messages contain 4 questions, mesauring pain intensity / pain unpleasentness (primary outcome), and stress / activation (secondary outcome).

Phillps tesla 1.5 fMRi, pathway pain stimulator (Medoc, Israel) fMRI under pain stimulation for 60 participants. 20 recieve active tDCS, 20 recieve sham-tDCS, 20 age and gender matched (matched to active tDCS group) healthy controls. Baseline scan, post treatment scan.

Time from inclusion to treatment start determines 30\14 days. Rating scales on Samsung Galaxy tab 10.1. HADS mesure anxiety and depression, SCL 90 measure symtoms of mental illness, SF36 mesure health related life quality, FIQ mesure symptom severity in fibromyalgia.

Pain (intensity and unpleasentness) measured with Visual Analog Scale. 3 times daily (0900hrs, 1500hrs, 2100hrs). A randomly selected sample of participants have VAS measured with SMS for 30 days pre treatment. Intention is to gather natural history sample to compare with a similarly lengthed post-treatment period.

Stress and activation measured with Visual Analog Scale. Repported at 3 points daily (0900hrs, 1500hrs, 2100hrs) using Short Message System (SMS) 14 days pre-treatment (baseline), during treatment 5 days, and 30 days post-treatment. Measure effect of active\sham tDCS on stress and activation. 2 levels of group (active tDCS\ sham tDCS, 7 repeated measures: pre-treatment day 1, 2 ,3, 4, 5 - post) Measured using the same instrumet as the primary outcome.

Stress and activation measured with Visual Analog Scale. 3 times daily (0900hrs, 1500hrs, 2100hrs). A randomly selected sample of participants have VAS measured with SMS for 30 days pre treatment. Intention is to gather natural history sample to compare with a similarly lengthed post-treatment period.

Inclusion Criteria: Fibromyalgia (ACR-90 criteria, M79.7 ICD10) Mean VAS > 4 daily 2 weeks prior to study). Exclusion Criteria: Severe mental disease CNS disease Mental retardation Age < 18