High-frequency rTMS over the dorsolateral prefrontal cortex on chronic and provoked pain: A systematic review and meta-analysis

Xianwei Che; Robin F H Cash; Xi Luo; Hong Luo; Xiaodong Lu; Feng Xu; Yu-Feng Zang; Paul B Fitzgerald; Bernadette M Fitzgibbon

doi:10.1016/j.brs.2021.07.004

High-frequency rTMS over the dorsolateral prefrontal cortex on chronic and provoked pain: A systematic review and meta-analysis

Brain Stimul. 2021 Sep-Oct;14(5):1135-1146. doi: 10.1016/j.brs.2021.07.004. Epub 2021 Jul 16.

Authors

Xianwei Che¹, Robin F H Cash², Xi Luo³, Hong Luo⁴, Xiaodong Lu⁵, Feng Xu⁶, Yu-Feng Zang⁷, Paul B Fitzgerald⁸, Bernadette M Fitzgibbon⁹

Affiliations

¹ Centre for Cognition and Brain Disorders, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, China; Institutes of Psychological Sciences, Hangzhou Normal University, Hangzhou, China; Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments, Hangzhou, China. Electronic address: xwcheswu@gmail.com.
² Melbourne Neuropsychiatry Centre, The University of Melbourne, Victoria, Australia; Department of Biomedical Engineering, The University of Melbourne, Victoria, Australia.
³ Shenzhen Key Laboratory of Affective and Social Cognitive Science, School of Psychology, Shenzhen University, Shenzhen, China.
⁴ Children and Adolescents Mental Health Joint Clinic, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, China.
⁵ Department of Neurology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, China.
⁶ Shenzhen Yingchi Technology Co., Ltd, China.
⁷ Centre for Cognition and Brain Disorders, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, China; Institutes of Psychological Sciences, Hangzhou Normal University, Hangzhou, China; Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments, Hangzhou, China.
⁸ Epworth Centre for Innovation in Mental Health, Epworth Healthcare and Monash University Department of Psychiatry, Victoria, Australia.
⁹ Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Australia.

PMID: 34280583
DOI: 10.1016/j.brs.2021.07.004

Abstract

Background: High-frequency rTMS over the dorsolateral prefrontal cortex (DLPFC) has demonstrated mixed effects on chronic and provoked pain.

Objectives/methods: In this study, a meta-analysis was conducted to characterise the potential analgesic effects of high-frequency rTMS over the DLPFC on both chronic and provoked pain.

Results: A total of 626 studies were identified in a systematic search. Twenty-six eligible studies were included for the quantitative review, among which 17 modulated chronic pain and the remaining investigated the influence on provoked pain. The left side DLPFC was uniformly targeted in the chronic pain studies. While our data identified no overall effect of TMS across chronic pain conditions, there was a significant short-term analgesia in neuropathic pain conditions only (SMD = -0.87). In terms of long-lasting analgesia, there was an overall pain reduction in the midterm (SMD = -0.53, 24.6 days average) and long term (SMD = -0.63, 3 months average) post DLPFC stimulation, although these effects were not observed within specific chronic pain conditions. Surprisingly, the number of sessions was demonstrated to have no impact on rTMS analgesia. In the analysis of provoked pain, our data also indicated a significant analgesic effect following HF-rTMS over the DLPFC (SMD = -0.73). Importantly, we identified a publication bias in the studies of provoked pain but not for chronic pain conditions.

Conclusions: Overall, our findings support that HF-DLPFC stimulation is able to induce an analgesic effect in chronic pain and in response to provoked pain. These results highlight the potential of DLPFC-rTMS in the management of certain chronic pain conditions and future directions are discussed to enhance the potential long-term analgesic effects.

Keywords: Analgesia; DLPFC; High-frequency; Pain; meta-Analysis; rTMS.

Publication types

Meta-Analysis
Research Support, Non-U.S. Gov't
Review
Systematic Review

MeSH terms

Chronic Pain* / therapy
Humans
Pain Management
Pain Measurement
Prefrontal Cortex
Transcranial Magnetic Stimulation*