Evidence for Intermittent Theta Burst Transcranial Magnetic Stimulation for Dysphagia after Stroke: A Systematic Review and Meta-analysis.

Dysphagia is the most common serious complication after stroke, with an incidence of about 37-78%, which seriously affects the independence of patients in daily life and clinical recovery. Repetitive transcranial magnetic stimulation (rTMS), as a non-invasive neuromodulation technique, is an emerging option for post-stroke dysphagia. Theta burst stimulation (TBS) is a new mode of transcranial magnetic stimulation that simulates the frequency of pulses released in the hippocampus.Intermittent theta burst stimulation (iTBS) has been shown to increase cortical excitability and improve swallowing function in patients. Our study sought to summarize existing clinical randomized controlled trials to provide evidence-based medical evidence for the clinical use of iTBS. A computer search was conducted on 4 Chinese (Chinese Biomedical Literature Database, VIP Information Resource System, CNKI, and Wanfang Medical Science) and 4 English (including Cochrane Library, Embase, PubMed, Web of Science) databases to retrieve all randomized controlled trials in Chinese and English that explored the effects of Intermittent Theta Burst Stimulation for post-stroke dysphagia. The retrieval years are from database construction to 23 November 2023. The primary outcome measure was a change in Penetration/Aspiration Scale (PAS), Standardized Swallowing Assessment (SSA) and Functional Oral Intake Scale (FOIS), Secondary outcomes included Fiberoptic Endoscopic Dysphagia Severity Scale (FEDSS), water-swallowing test (WST) etc. A meta-analysis by Standardized Mean Difference (SMD) and 95% confidence interval (CI) was performed with RevMan 5.3. we appraise risk of bias(RoB) of each study with the Cochrane RoB tool. Detailed instructions for using the Cochrane RoB tool are provided in the Cochrane Handbook for Systematic Reviews of Interventions (The Cochrane Handbook). Nine studies were obtained from eight databases after screening by inclusion and exclusion criteria, 567 patients from 9 studies were included in the meta-analysis, and one study was included in the qualitative analysis due to different control groups. Two of the nine studies had an unclear risk of bias, and four studies were at low risk. The results showed that iTBS significantly improved SSA, PAS, FOIS, and PAS scores in stroke patients compared to the control group(P < 0.05), and promoted swallowing function recovery. Our systematic review provides the first evidence of the efficacy of iTBS in improving dysphagia in stroke patients. However, the number of available studies limits the persuasiveness of the evidence and further validation by additional randomized controlled trials is needed.