Scrambler therapy improves pain in neuromyelitis optica: a randomized controlled trial

Objective: The primary objective aimed to determine if Scrambler therapy is an effective, acceptable and feasible treatment of persistent central neuropathic pain in patients with neuromyelitis optica spectrum disorder (NMOSD). The secondary objective explored the effect of Scrambler therapy on co-occurring symptoms.

Methods: We conducted a randomized single blind, sham-controlled trial in patients with NMOSD who have central neuropathic pain using Scrambler therapy for 10 consecutive weekdays. Pain severity, pain interference, anxiety, depression and sleep disturbance were assessed at baseline, end of treatment, and at 30- and 60-day follow-up.

Results: Twenty-two patients (11 per arm) were enrolled into and completed this trial. The median baseline NRS pain score decreased from 5.0 to 1.5 following 10 days of treatment with Scrambler therapy, whereas the median NRS score did not significantly decrease in the sham arm. Depression was also reduced in the treatment arm, and anxiety was decreased in a subset of patients who responded to treatment. These symptoms were not impacted in the sham arm. The safety profiles were similar between groups.

Conclusions: Scrambler therapy is an effective, feasible and safe intervention for central neuropathic pain in patients with NMOSD. Decreasing pain with Scrambler therapy may additionally improve depression and anxiety. Clinicaltrials.gov identifier NCT03452176 Classification of Evidence This study provides Class II evidence for patients with NMOSD and persistent central neuropathic pain that Scrambler therapy significantly reduces pain.