Cerebellar transcranial magnetic stimulation in essential tremor: a systematic review and meta-analysis of safety and efficacy.

Background: Essential tremor (ET) is a common neurological disorder that significantly impacts daily activities. This meta-analysis aims to evaluate the safety and efficacy of cerebellar repetitive Transcranial Magnetic Stimulation (rTMS) and cerebellar Theta Burst Stimulation (TBS) in treating ET.

Methods: We searched through June 14, 2024, four databases (Scopus, PubMed, Web of Science, and Cochrane CENTRAL) to identify clinical trials investigating cerebellar rTMS or TBS in ET patients. Eligibility criteria included clinical trials reporting on safety and efficacy outcomes. Six reviewers screened and extracted data independently, resolving conflicts through consensus. Risk of bias was assessed. Statistical analyses involved pooling continuous outcomes using the mean difference (MD) and 95% confidence intervals (CI) with RevMan 5.3.

Results: Out of 201 screened studies, nine studies were included, with a total of 261 participants (149 received rTMS, 112 were in control groups). The meta-analysis revealed no statistically significant difference between rTMS and sham groups for Fahn-Tolosa-Marin (FTM) subscores A (MD: -3.03, 95% CI: [-7.66, 1.60], P = 0.20), B (MD: -2.74, 95% CI: [-8.09, 2.61], P = 0.32), C (MD: -1.57, 95% CI: [-5.12, 1.97], P = 0.38), and FTM-Total (MD: -8.12, 95% CI: [-20.47, 4.23], P = 0.20). Sensitivity analysis confirmed these results. Adverse events were minimal: headaches (1/44 rTMS, 2/19 sham), dizziness (1/44 rTMS, 0/19 sham), and no reported seizures or syncope.

Conclusion: While individual studies noted significant FTM score improvements post-rTMS treatment, the pooled analysis found no significant differences versus sham. Further research with standardized protocols and larger samples is required to optimize rTMS use for ET.