Anodal transcranial direct current stimulation can relieve aphasia among stroke survivors: A meta-analysis of randomized and controlled trials

Abstract

Objective To systematically review the efficacy of anodal transcranial direct current stimulation (A-tDCS) for relieving aphasia among stroke survivors. Methods The Chinese BioMedical Literature database, China National Knowledge Infrastructure, WanFang database, Chinese Scientific Journals full-text database, PubMed, Embase, MEDLINE and the Cochrane Library for clinical randomized and controlled trials were searched for reports about the use of A-tDCS in the treatment of aphasia after stroke. The resulting reports were retrieved manually and evaluated by two independent reviewers according to pre-set inclusion and exclusion criteria. The reports covered the period to November 2016. A meta-analysis was then conducted using RevMan software version 5.3. Results Seven studies covering 101 patients were selected for analysis. Meta-analysis showed that the average aphasia function score improved after A-tDCS significantly more than in the control group. Picture naming ability in stroke survivors with aphasia showed particular improvement. Only 11 patients in the 7 studies presented light adverse effects from A-tDCS, always within the patients′ tolerance range. Conclusion A-tDCS can significantly improve the speech of patients with aphasia after cerebral infarction. It is safe and easy to administer and is a rehabilitation technology worth popularizing and applying. Considering the limited number of articles, the conclusion remains to be further verified with randomized clinical trials of higher quality and a larger sample. Key words: Transcranial direct current stimulation; Stroke; Aphasia; Meta-analyses