Transcranial direct current stimulation improves swallowing function in stroke patients

Abstract

Background: Poststroke dysphagia can persist, leading to many complications.

Objective: We investigated whether noninvasive brain stimulation to the pharyngeal motor cortex combined with intensive swallowing therapy can improve dysphagia.

Methods: A total of 20 patients who had dysphagia for at least 1 month after stroke were randomly assigned to receive 10 sessions lasting 20 minutes each of either 1-mA anodal transcranial direct current stimulation (tDCS) or a sham procedure to the ipsilesional pharyngeal motor cortex, along with simultaneous conventional swallowing therapies. We evaluated swallowing function with the dysphagia outcome and severity scale (DOSS) before, immediately after, and 1 month after the last session.

Results: Anodal tDCS resulted in an improvement of 1.4 points in DOSS (P = .006) immediately after the last session and 2.8 points (P = .004) 1 month after the last session. The sham tDCS group improved 0.5 points (P = .059) after the last session and 1.2 points (P = .026) 1 month after the final session. The improvements in the anodal tDCS group were significantly greater than those in the sham tDCS group (P = .029 after the last session, and P = .007 1 month after the last session).

Conclusions: Anodal tDCS to the ipsilesional hemisphere and simultaneous peripheral sensorimotor activities significantly improved swallowing function as assessed by the DOSS.