Anodal tDCS of the swallowing motor cortex for treatment of dysphagia in multiple sclerosis: a pilot open-label study

Swallowing difficulties are a common symptom of multiple sclerosis (MS). The early detection and treatment of dysphagia is critical to prevent complications, including poor nutrition, dehydration, and lung infections. Recently, transcranial direct current stimulation (tDCS) has been proven to be effective in ameliorating swallowing problems in stroke patients. In this pilot study, we aimed to assess safety and efficacy of transcranial direct current stimulation (tDCS) in the treatment of dysphagia in MS patients. We screened 30 patients by using the 10-item DYsphagia in MUltiple Sclerosis (DYMUS) questionnaire, and patients at risk for dysphagia underwent a clinical and fiberoptic endoscopic evaluation of swallowing (FEES). Six patients who presented with mild to moderate dysphagia underwent the experimental procedures. These consisted of 5 sessions of anodal tDCS applied in consecutive days over the right swallowing motor cortex. Patients were followed-up at 1 week, 1 month and 3 months after treatment, and changes in the Dysphagia Outcome and Severity Scale (DOSS) score between baseline and post-tDCS were assessed. Our results showed that in all patients, the tDCS treatment determined a mild but significant clinical benefit (one-point improvement in the DOSS score) lasting up to 1 month. In conclusion, our preliminary results show that anodal tDCS has therapeutic potential in the treatment of swallowing problems in patients suffering with MS. However, future double-blind, randomized, and sham-controlled studies are needed to confirm the present findings.