High-frequency repetitive transcranial magnetic stimulation at dorsolateral prefrontal cortex for migraine prevention: A systematic review and meta-analysis

Utility of Repetitive Transcranial Magnetic Stimulation for Chronic Daily Headache Prophylaxis: A Systematic Review and Meta-Analysis

PURPOSE OF REVIEW

Management of chronic daily headaches (CDH) remains challenging due to the limited efficacy of standard prophylactic pharmacological measures. Several studies have reported that repetitive transcranial magnetic stimulation (rTMS) can effectively treat chronic headaches. The objective was to determine the utility of rTMS for immediate post-treatment and sustained CDH prophylaxis.

RECENT FINDINGS

All procedures were conducted per PRISMA guidelines. PubMed, Scopus, Web of Science, and ProQuest databases were searched for controlled clinical trials that have tested the efficacy of rTMS on populations with CDH. DerSimonian-Laird random-effects meta-analyses were performed using the 'meta' package in R to examine the post- vs. pre-rTMS changes in standardized headache intensity and frequency compared to sham-control conditions. Thirteen trials were included with a combined study population of N = 538 patients with CDH (rTMS, N = 284; Sham, N = 254). Patients exposed to rTMS had significantly reduced standardized CDH intensity and frequency in the immediate post-treatment period (Hedges' g = -1.16 [-1.89, -0.43], p = 0.002 and Δ = -5.07 [-10.05, -0.11], p = 0.045 respectively). However, these effects were sustained marginally in the follow-up period (Hedges' g = -0.43 [-0.76, -0.09], p = 0.012 and Δ = -3.33 [-5.52, -1.14], p = 0.003). Significant between-study heterogeneity was observed, at least partially driven by variations in rTMS protocols. Despite the observed clinically meaningful and statistically significant benefits in the immediate post-treatment period, the prophylactic effects of rTMS on CDH do not seem to sustain with discontinuation. Thus, the cost-effectiveness of the routine use of rTMS for CDH prophylaxis remains questionable.

REGISTRATION

Protocol preregistered in PROSPERO International Prospective Register of Systematic Reviews (CRD42021250100).

Neuromodulation Techniques for Headache Management

This narrative review aims to summarize evidence regarding the current utilization and future applications of neuromodulation in patients with headaches, with special attention paid to migraine and chronic cluster headache. A search was conducted in PubMed in August of 2023 to survey the current literature on neuromodulation for the treatment of headache. In total, the search yielded 1989 results, which were further filtered to include only systematic reviews published between 2022 to 2023 to capture the most up-to-date and comprehensive research on this topic. The citation lists of these articles were reviewed to find additional research on neuromodulation and supplement the results presented in this paper with primary literature. Research on the use of neuromodulation for the treatment of headache has predominantly focused on four neuromodulation techniques: peripheral nerve stimulation (PNS), transcranial magnetic stimulation (TMS), deep brain stimulation (DBS), and spinal cord stimulation (SCS). Outcome measures reported in this article include impact on migraine and headache frequency and/or pain intensity, adverse effects of the neuromodulation technique, and associated costs, when available. We found that neuromodulation has developed utility as an alternative treatment for both chronic cluster headaches and migraines, with a reduction in frequency and intensity of headache most elucidated from the articles mentioned in this review.

Transcranial Magnetic Stimulation as a Therapy for Migraine: An Overview of Systematic Reviews

Introduction

This overview of systematic reviews (SRs) systematically collected, evaluated, and combined the evidence for migraine treatment with transcranial magnetic stimulation (TMS).

Methods

We conducted a systematic literature search in various databases, such as PubMed, The Cochrane Library, Web of Science, Embase, the China National Knowledge Infrastructure, Wanfang, VIP, and China Biomedical Literature. Two reviewers independently assessed the methodological quality, risk of bias, reporting quality, and strength of evidence of the included studies using AMSTAR-2, ROBIS, the PRISMA checklist, and the GRADE system.

Results

We performed an overview of 7 relevant SRs, of which 4 were of moderate quality and 3 were of low quality according to AMSTAR 2. All SRs had low risk of bias in Phase 1 (Assessing relevance), Domain 1 (Study eligibility criteria), and Domain 4 (Synthesis and findings) as evaluated by ROBIS. In Domain 2 (Identification and selection of studies), 4 SRs (57.1%) had low risk of bias, while in Domain 3 (data collection and study appraisal) and Risk of Bias in the Review Phase 3, 4 SRs (57.1%) had low risk of bias. The PRISMA reporting standards were generally comprehensive, but some limitations were observed in the assessments, pooled results, evidence reliability, registration and protocols, and funding sources. The GRADE levels ranged from moderate to low, with 10 outcomes of moderate quality and 6 outcomes of low quality. The main reason for the low quality of evidence was the small sample size and high heterogeneity of the available studies.

Conclusion

TMS may improve migraine severity and frequency, but the evidence is limited due to methodological flaws and heterogeneity. Future studies should standardize use, assess side effects, and compare with other treatments.

Repetitive transcranial magnetic stimulation for cerebellar ataxia: a systematic review and meta-analysis

Background

Repetitive transcranial magnetic stimulation, a non-invasive brain stimulation technique, can manage cerebellar ataxia (CA) by suppressing cerebral cortical excitability. Hence, this study aimed to summarize the efficacy and safety of rTMS for CA patients by meta-analysis.

Methods

The PubMed, Embase, Web of Science, and Cochrane Library databases were searched for eligible studies published till 20 May 2023. Weighted mean difference (MD) and 95% confidence intervals (CIs) were used to assess the effect of rTMS treatment. Additionally, the quality of the included studies and the risk of bias were evaluated using the Physiotherapy Evidence Database (PEDro) scale.

Results

Overall, eight studies involving 278 CA patients were included in this meta-analysis. rTMS could significantly improve the Scale for the Assessment and Rating of Ataxia (SARA) (MD: -2.00; 95% CI: -3.97 to -0.02, p = 0.05), International Cooperative Ataxia Rating Scale (ICARS) (MD: -3.96; 95% CI: -5.51 to -2.40, p < 0.00001), Timed Up-and-Go test (TUG) (MD: -1.54; 95% CI: -2.24 to -0.84, p < 0.0001), 10-m walk test (10 MWT) (MD10-m steps: -2.44; 95% CI: -4.14 to -0.73, p = 0.005), and Berg Balance Scale (BBS) (MD: 2.59; 95% CI: 1.15-4.03, p = 0.0004) as compared to sham stimulation. Active rTMS was not significantly different from sham rTMS in changing the duration (MD10-m time: -1.29; 95% CI: -7.98 to 5.41, p = 0.71). No severe adverse events were observed in both sham stimulation and active rTMS groups.

Conclusion

This meta-analysis provides limited evidence that rTMS may be beneficial in treating CA patients. However, these findings should be treated with caution due to the limitations of the smaller sample size and the inconsistent approach and target of rTMS treatment. Therefore, more large-scale RCTs are required to further validate our analytical findings.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=295726, identifier: CRD42022295726.