Transcranial direct current stimulation in inflammatory bowel disease patients modifies resting-state functional connectivity: A RCT

Chronic pain is known to be associated with functional and structural changes in the brain. Inflammatory bowel disease (IBD) presents with chronic abdominal pain in almost 35% of all patients. This study investigates structural and functional changes in magnetic resonance imaging (MRI) after transcranial direct current stimulation (tDCS) applied to ameliorate pain in IBD. This phase-III, placebo-controlled, randomized study included 36 patients with IBD and chronic pain. MRI scans were performed before and following tDCS, which was applied for 5 days. For the first time, this study revealed an association of changes in resting-state functional MRI and pain reduction in IBD. There was a significant increase in functional connectivity after active tDCS within the visual medial and the right frontoparietal network being connected with the amygdala, the insula, and the primary somatosensory cortex indicating central pain mechanisms in IBD. Moreover, tDCS offers a novel therapeutic strategy for abdominal pain. •Analgesic effects of tDCS are associated with changes in resting-state fMRI in IBD.•Chronic abdominal pain in IBD seems to operate on a central level.•The brain-gut-axis is involved in a bidirectional manner.•Implications for patient care: Pain therapy for IBD should incorporate this knowledge.