Effectiveness of Repetitive Transcranial Magnetic Stimulation on Managing Fibromyalgia: A Systematic Meta-Analysis.

OBJECTIVE: In fibromyalgia, central sensitization is a key mechanism, and repetitive transcranial magnetic stimulation (rTMS) has been reported to potentially manage symptoms of fibromyalgia. In this meta-analysis, we evaluated the therapeutic effect of rTMS in patients with fibromyalgia according to stimulation locations and follow-up time points. METHODS: We searched the MEDLINE, Cochrane, Embase, Scopus, Cumulative Index to Nursing and Allied Health Literature, and Web of Science databases for articles published from January 1, 1990, to August 26, 2021, including randomized controlled studies investigating the effectiveness of rTMS on managing fibromyalgia. RESULTS: In total, 10 articles and 299 participants were included. High-frequency rTMS on the left primary motor cortex (Lt. M1) had a significant effect on pain reduction immediately and 1-4 weeks after the end of the session but had no significant effect after 5-12 weeks. Additionally, after high-frequency rTMS sessions on the Lt. M1, the effect on patients' quality of life appeared late at 5-12 weeks of follow-up. In contrast, high-frequency rTMS on the left dorsolateral prefrontal cortex (Lt. DLPFC) did not reduce pain from fibromyalgia. The effect on controlling the affective problem was not observed after rTMS treatment on either the Lt. M1 or the Lt. DLPFC. CONCLUSIONS: High-frequency rTMS had a positive pain-reducing effect immediately and at 1-4 weeks after completion of the rTMS sessions, and the patients' quality of life improved after 5-12 weeks. However, Lt. DLPFC stimulation was not effective in controlling fibromyalgia symptoms.