Electroencephalographic changes following trigeminal nerve stimulation for major depressive disorder: study protocol for a randomized sham-controlled trial

Abstract

Background: Major depressive disorder (MDD) is one of the most common psychiatric disorders. Trigeminal nerve stimulation (TNS) is a novel neuromodulation technology with impressive initial results in the treatment of MDD that lacks a better evaluation of neurobiological mechanisms of action. Methods/Design: This is a two-arm, randomized, double-blind, sham-controlled trial to evaluate the effect of TNS on severe MDD through quantitative electroencephalography (QEEG) pre and post intervention. Forty-four patients diagnosed with severe MDD will be randomly assigned to either a 10-session treatment protocol of real TNS or a 10-session treatment protocol of sham TNS. Outcome measures will be evaluated at baseline, at the end of the stimulation protocol and 30 days after the end of the 10-day treatment period. The primary outcome is changes in the previously established frequency band ranges in QEEG during resting state. The secondary outcome is heart rate variability for better evaluation of the sympathetic and parasympathetic changes after TNS. Discussion: Due to the high prevalence of MDD, the limited effect of antidepressant medications, the high rate of intolerable adverse events, and the high rate of refractoriness, we believe non-invasive neuromodulation strategies, e.g., TNS can be a useful tool for the treatment of MD. The evaluation of the effect of TNS with QEEG before and after stimulation may help us clarify the mechanisms involved in the clinical responses. Trial registration: ClinicalTrials.gov identifier: NCT02562703, registered on 25 September 2015. Ethics: This study protocol has been approved by the institutional review board (IRB) (approval number: 30960814.7.0000.5479) and will be performed in accordance with the Declaration of Helsinki. Informed consent: Patients will sign an informed consent prior to participation in the study.