Transcranial Direct Current Stimulation Over the Vagus Nerve Promotes Poststroke Dysphagia Recovery: A Randomized, Double-Blind, Sham-Controlled Clinical Trial

Abstract

Objective: The aim of this study was to confirm whether transcranial direct current stimulation over the vagus nerve can improve swallowing function in patients with poststroke dysphagia.

Design: This is a parallel-group, randomized, double-blind, sham-controlled clinical trial.

Methods: Sixty-four patients with poststroke dysphagia were randomly allocated to receive real or sham transcranial direct current stimulation over the vagus nerve combined with routine swallowing rehabilitation therapy. Swallowing function was assessed by Fiberoptic Endoscopic Dysphagia Severity Scale, Modified Mann Assessment of Swallowing Ability Scale, Functional Communication Measure, and Rosenbek Penetration-Aspiration Scale before and after treatment.

Results: After 4 weeks of treatment, swallowing function improved in both the transcranial direct current stimulation over the vagus nerve group and control group. Intragroup changes in the Fiberoptic Endoscopic Dysphagia Severity Scale, Modified Mann Assessment of Swallowing Ability Scale, Functional Communication Measure, and Rosenbek Penetration-Aspiration Scale scores were more significant in the transcranial direct current stimulation over the vagus nerve group than in the control group.

Conclusions: This preliminary study suggested that the performance of transcranial direct current stimulation over the vagus nerve improved the swallowing function in patients with poststroke dysphagia and extended the clinical application of transcranial direct current stimulation in poststroke dysphagia.

Keywords: Dysphagia; Stroke; Transcranial Direct Current Stimulation; Vagus Nerve.