The effects of transcranial direct-current stimulation (tDCS) on pain intensity of patients with fibromyalgia: a systematic review and meta-analysis

Abstract

Introduction Fibromyalgia (FM) is a chronic pain condition that affects millions of people worldwide. Transcranial Direct Current Stimulation (tDCS) is a non-invasive brain stimulation technique that has shown promise as a potential treatment for FM by modulating pain perception and reducing symptoms, such as fatigue and depression. We aimed to systematically review studies that assess the effect of tDCS on pain reduction in FM patients. Methods Seven electronic databases (PubMed, Scopus, Embase, PsycINFO, Web of Science, Cochrane, and CINAHL Complete) were searched for records in English. Studies that measured the effect of tDCS on pain intensity in FM patients were included. The Cochrane Collaboration’s tool was used to assess the quality of the included studies. A random-effect model was preferred, and statistical analysis was performed by Stata software version 17. Results Twenty studies were included for qualitative, and eleven for quantitative analysis. Out of 664 patients included in the study, 443 were in the stimulation group. The left M1 area was the most common stimulation target (n = 12), and 2 mA was the most common stimulation amplitude (n = 19). The analysis showed that active tDCS significantly reduced pain intensity in FM patients in comparison to the sham group (SMD= -1.55; 95% CI -2.10, -0.99); also, no publication bias was noted. Conclusion Our systematic review highlights the potential effect of tDCS on the reduction of pain intensity in FM patients. Additionally, this current evidence could suggest that tDCS applied at an intensity of 2mA to the left M1 is the most effective strategy.

Fibromyalgia: one year in review 2024

“…Regarding tDCS protocols, anodal stimulation is generally applied in sessions of 20 minutes, at an intensity of 1.5-2 mA, with a minimum of 5 sessions. The most effective strategy to achieve pain relief of active tDCS seems to be the application at an intensity of 2mA to the left M1 (45).…”

“…Settings and modalities of treatment should be modulated on patient's needs and major symptoms (31)(32)(33)(34)(35)(36)(37)(38)(39). • Among electrophysical agents, evidences about the effectiveness of TMS and tDCS (applicated adjacent to DLPFC or to M1) are growing; their mechanisms of action worth to be investigated more (40)(41)(42)(43)(44)(45)(46)(47). • Acupuncture seems to improve pain and other symptoms in FM patients.…”

Maternal prenatal stress induces sex-dependent changes in tRNA fragment families and cholinergic pathways in newborns

“…Indeed, prenatal perceived stress (PPS) has been associated with offspring neurodevelopmental impairments, including escalated neurobehavioral problems and greater vulnerability towards developing psychiatric disorders later in life (12,13). Moreover, PPS was negatively correlated with fetal left hippocampal volume (14,15), infant cognitive performance at 18 months (8), and newborn telomeres length (16,17). In some cases, these effects were shown to be sex-specific, pointing mainly at male newborns as more vulnerable (9,18).…”

Efficacy of Transcranial Direct Current Stimulation on Pain Level and Disability of Patients with Fibromyalgia: A Systematic Review of Randomized Controlled Trials with Parallel-Group Design

“…Accordingly, there is a need to update the current literature on the efficacy of tDCS for FM. The most recent systematic review of this topic included studies published until June 2022 and included studies without control and placebo groups as well [17]. One novel aspect of the current systematic review compared to recent reviews and meta-analyses [11,17,18] is that we only included randomized controlled trials that applied tDCS (no other electrical stimulation and no combined intervention) in a parallel-group design with a sham control group.…”

“…The most recent systematic review of this topic included studies published until June 2022 and included studies without control and placebo groups as well [17]. One novel aspect of the current systematic review compared to recent reviews and meta-analyses [11,17,18] is that we only included randomized controlled trials that applied tDCS (no other electrical stimulation and no combined intervention) in a parallel-group design with a sham control group. This was to examine the sole and specific effects of active tDCS in reducing pain in FM patients and to prevent potential carry-over effects that might occur in studies with a cross-over design.…”