Repetitive transcranial magnetic stimulation for motor function in stroke: a systematic review and meta-analysis of randomized controlled studies.

Objective: This study aimed to systematically evaluate the safety and effectiveness of repetitive transcranial magnetic stimulation (rTMS) in treating motor dysfunction in stroke patients.

Methods: A systematic search was conducted in five online databases, namely, Medline, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL, and SPORTDiscus, from their inception to July 29, 2024. Studies meeting the predetermined inclusion criteria were included. The data were analyzed using RevMan 5.4.1 software and Stata 15.0. The subgroup analysis was conducted based on various disease stages and intervention frequencies. The overall effects were estimated using either the fixed effects model or the random effects model, with standardized mean differences (SMDs). The level of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework.

Results: A total of 70 studies encompassing 2951 stroke survivors were included. The results of the quantitative analysis revealed that the application of 1 Hz rTMS over the contralesional primary motor cortex (M1) significantly improved motor function during both the early stage (< 1 month) with moderate effect size (n = 443, SMD = 0.44, 95% CI 0.24 to 0.63, P < 0.00001, I² = 47%, fixed-effect model) and recovery period (1-6 months) with moderate effect size (n = 233, SMD = 0.61, 95% CI 0.34 to 0.87, P < 0.0001, I² = 33%, fixed-effect model). In the context of activities of daily living (ADLs), the application of 1 Hz rTMS over the contralesional M1 can lead to improvements in ADLs among individuals in the early stages of stroke with moderate effect size (n = 343, SMD = 0.67, 95% CI 0.44 to 0.89, I² = 79%, P < 0.00001, fixed-effect model). However, evidence to support that 1 Hz rTMS over contralesional M1 can improve motor dysfunction in the chronic phase of stroke (> 6 months) is insufficient.

Conclusion: Moderate- to high-quality evidence suggests that 1 Hz rTMS over the contralesional M1 may enhance motor function and independence in ADL during the early stages of stroke and the recovery period (within 6 months) with moderate effect. Nonetheless, as for the efficacy of 3, 5, 10, and 20 Hz rTMS in the treatment of motor dysfunction after stroke, it needs to be further determined. It is important to interpret these findings with caution in clinical practice due to the small sample sizes and low quality of the studies reviewed.

Systematic review registration: INPLASY, Registration number is INPLASY202360042. DOI number is https://doi.org/10.37766/inplasy2023.6.0042 .