Vestibular rehabilitation therapy in combination with transcranial direct current stimulation (tDCS) for treatment of chronic vestibular dysfunction in the elderly: a double-blind randomized controlled trial

INTRODUCTION: Dizziness and imbalance are common dysfunctions in the elderly. Vestibular rehabilitation therapy is an effective method to alleviate chronic dizziness in patients with vestibular dysfunction. Transcranial direct current stimulation has reportedly improved balance function in patients with vestibular dysfunction. OBJECTIVE: This study was conducted to investigate the therapeutic efficacy of vestibular rehabilitation combined with transcranial direct current stimulation in elderly patients with vestibular dysfunction. METHODS: In a double-blinded randomized controlled trial, 36 elderly patients with chronic vestibular dysfunction were randomly assigned to either vestibular rehabilitation and transcranial direct current stimulation (n = 18) or vestibular rehabilitation alone (n = 18) group. The transcranial stimulation protocol consisted of multisession bifrontal electrical stimulation of the dorsolateral prefrontal cortex (2 mA intensity and 20 min duration), followed by rehabilitation exercises. The vestibular rehabilitation protocol consisted of habituation and adaptation exercises combined with gait exercises during a three week period. The primary outcome of this study was the dizziness handicap inventory score, and the secondary outcomes were activities-specific balance confidence and Beck anxiety inventory scores. RESULTS: For the dizziness handicap score, the repeated-measures analysis of variance showed a significant main effect of “time”, “stimulation” and stimulation × time interaction effect. There was a significant reduction in the overall dizziness handicap score with “time” for both the groups, which was more pronounced in the vestibular rehabilitation and electrical stimulation group. In terms of activities-specific balance confidence change scores, we found a significant main effect of “time” and “stimulation” main factors, but this effect for stimulation × time interaction was not significant. For the Beck anxiety score, we observed a significant main effect of “time”, but no evidence for the main effect of the “stimulation” factor. CONCLUSION: Bifrontal transcranial direct current stimulation in combination with vestibular rehabilitation therapy is a promising approach to improve chronic vestibular symptoms in the elderly.