Cranial Electrotherapy Stimulation for Fibromyalgia in Veterans: A Randomized Sham-Controlled Feasibility Study of Resting-State Functional Connectivity Magnetic Resonance Imaging to Evaluate Pain and Treatment Response.

Abstract

Background: Fibromyalgia is a chronic pain disorder frequently co-occurring with depression, anxiety, post-traumatic stress disorder (PTSD), and insomnia, particularly in veterans, and safer nonpharmacological therapies are needed. Cranial electrotherapy stimulation, also referred to as cranial electrotherapy stimulation (CES), may help with anxiety and sleep, but its effect on pain is unclear. This feasibility study evaluated magnetic resonance imaging (MRI) to identify neural correlates of pain and treatment response for CES effects on fibromyalgia pain in veterans.

Methods: In a randomized, double-blind, sham-controlled trial at a single US government hospital, veterans aged 20 to 60 with fibromyalgia were assigned to active or sham in-home CES, stratified by sex. Participants self-administered CES for 60 minutes daily over 12 weeks. Resting-state functional magnetic resonance imaging (fMRI) was acquired at baseline, 6 weeks, and 12 weeks with clinical outcomes, including the Defense and Veterans Pain Rating Scale (DVPRS), National Institutes of Health (NIH) Patient-Reported Outcomes Measurement Information System (PROMIS) measures, and tests of physical function.

Results: Forty-eight participants were randomized (25 active, 23 sham) and 47 were analyzed. Both groups showed significant improvements in DVPRS pain (-1.88 ± 2.2) and pain interference with sleep (-2.25 ± 2.8), mood (-1.88 ± 2.6), activity (-1.83 ± 2.4) and stress (-1.77 ± 3.0) at 12 weeks versus baseline (P < .01), with significant between-group differences only in sleep (P = .04). Neuroimaging revealed significant increases in connectivity between the cerebellar 7b seed and the left occipital fusiform gyrus (0.079 ± 0.1) left lingual gyrus (0.063 ± 0.08), and right lingual gyrus (0.058 ± 0.08) for the CES group and decreases in the sham group (-0.088 ± 0.1; -0.121 ± 0.08; and -0.135 ± 0.1), respectively. No adverse events occurred.

Conclusions: Both groups improved similarly in pain and function, though new analgesic usage was more prevalent in the sham group. Neuroimaging revealed differential changes in cerebellar-sensory-visual networks and baseline patterns distinguishing responders from nonresponders, supporting feasibility and design of larger, adequately powered CES trials in fibromyalgia.