The Effect and Optimal Parameters of Repetitive Transcranial Magnetic Stimulation on Poststroke Dysphagia: A Meta-Analysis of Randomized Controlled Trials

Abstract

ObjectiveThe objectives of the study were to evaluate the efficacy of repetitive transcranial magnetic stimulation (rTMS) treatment for poststroke dysphagia (PSD) and explore the optimal stimulation parameters.MethodThe databases of Medline, Embase, Web of Science, and Cochrane Library were searched from the establishment to June 2021. All randomized controlled trials about rTMS treatment for PSD were enrolled. Dysphagia Grade (DG) and Penetration Aspiration Scale (PAS) were applied as the major dysphagia severity rating scales to evaluate the outcomes.ResultsA total of 12 clinical randomized controlled studies were included in our study. The summary effect size indicated that rTMS had a positive effect on PSD (SMD = −0.67, p < 0.001). The subgroup analysis for treatment duration and different stroke stages showed significant differences (treatment duration >5 days: SMD = −0.80, p < 0.001; subacute phase after stroke: SMD = −0.60, p < 0.001). Furthermore, no significant differences were observed among the other stimulation parameter subgroups (including stimulation frequency, location, and a single stimulation time) (p > 0.05).ConclusionrTMS is beneficial to the recovery of PSD patients, while an intervention of more than 5 days and in the subacute phase after stroke might bring new strategies and rational therapeutics to the treatment of PSD.Systematic Review Registrationhttp://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022299469.

Effects of Insular Cortex on Post-Stroke Dysphagia: A Systematic Review and Meta Analysis

“…For example, noninvasive brain stimulation (NIBS), including repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), is a practical technique which has proved effective, and is widely used to promote the recovery of PSD [ 56 ]. However, the rTMS relies on accurate stimulation at specific brain regions to achieve clinical efficacy [ 57 ]. Therefore, the insular cortex may become the target in the treatment of PSD and aspiration.…”

Effects of repetitive transcranial magnetic stimulation on sequelae in patients with chronic stroke: A systematic review and meta-analysis of randomized controlled trials

“…Transcranial magnetic stimulation may induce cortical plasticity in the human brain networks involved in language function, thus promoting language improvement (Szaflarski et al, 2021 ). In contrast, for post-stroke dysphagia, early rTMS intervention may better facilitate recovery (Qiao et al, 2022 ).…”

Assessment and treatment of neurogenic dysphagia in stroke and Parkinson's disease

“…A minimum number of five sessions seems to be required for rTMS to obtain a significant clinical benefit on dysphagia [99 ▪▪ ]. However, future studies are needed to define the optimal duration of NIBS treatment.…”

“…Conflicting findings are partly because of the low number of studies, assessing the therapeutic effects of low-frequency rTMS [106]. Furthermore, it should be considered, which hemisphere is stimulated: Qiao et al [99 ▪▪ ] found that while high-frequency rTMS can improve dysphagia when applied to the ipsilesional hemisphere (i.e. the damaged hemisphere), low-frequency rTMS is mainly effective when applied to the contralesional hemisphere (i.e.…”