Impact of Susceptibility to Placebo on the Effect of Transcranial Direct Current Stimulation (tDCS) in Fibromyalgia

NCT05845528 | Completed

• 1 other identifier: 20200383
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

Fibromyalgia (FM) is a syndrome characterized by generalized musculoskeletal pain, fatigue, non-restorative sleep, cognitive changes, depressive and neurovegetative symptoms. It is known that conventional pharmacological therapies produce responses with little clinical impact in more than 50% of patients. Functional alterations of the motor cortex and its connections with subcortical structures have also been demonstrated in FM. Based on the above, the objective of this research is to identify subgroups of patients with greater potential for responsiveness to treatment with a view to advancing diagnosis and treatment. In this study, the therapeutic target will be transcranial direct current stimulation (tDCS) according to the potential of responsiveness to the placebo effect, with the precise location of the stimulation area by a neuronavigation system, with the objective of counter-regulating the dysfunctional processes responsible for triggering and maintaining FM symptoms. Therefore, this clinical trial aims to compare the efficacy of anodal tDCS applied to the left dorsolateral prefrontal cortex (DLPFC) compared to simulated tDCS in FM, according to susceptibility to placebo effect and serum endorphin levels.

Conditions

Fibromyalgia

Keywords

Fibromyalgia; tDCS; placebo effect; pain; b-endorphin

Outcome Measures

Primary Outcomes (2)

• 1.Change in pain level - first phase

  Change from before and after the First phase of treatment on Pain scores assessed by a Numerical Pain Scale (NPS 0 to 10) (0 means no pain - 10 means the worst pain imaginable)

  Time Frame: 1 month

• Change in functional capacity - first phase

  The Brief Pain Inventory (BPI) rapidly assesses the severity of pain and its impact on functioning

  1 month

Secondary Outcomes (5)

• Change in pain level - second phase

  3 months

• Change in functional capacity - second phase

  3 months

• Change in Function of modulatory descending system

  1 month

• Change in Function of corticospinal pathway

  Time Frame: 1 month

• 7. Change in levels of Brain derived neurotrophic factor - BDNF

  Time Frame: 1 month

Study Arms (2)

Respondres placebo effect

PLACEBO COMPARATOR

Intervention: 'Transcranial Direct Current Stimulation - tDCS * The patients will receive tDCS stimulation treatment prefrontal cortex dorso lateral * According to 10-20 EEG system, anode will be placed at left F3 and cathode at contralateral F4. * Placebo stimulation uses a 2 milliamperes current during in the first minutes, in the 10 min and in 19 minutes.

Device: s-tDCS; Device: a- tDCS

No respondres placebo effect

ACTIVE COMPARATOR

Intervention: 'Transcranial Direct Current Stimulation - tDCS * The patients will receive tDCS stimulation treatment prefrontal cortex dorso lateral * According to 10-20 EEG system, anode will be placed at left F3 and cathode at contralateral F4. * Active stimulation uses a 2 milliamperes current during 20 minutes.

Device: s-tDCS; Device: a- tDCS

Interventions

s-tDCS DEVICE

\- Intervention: tDCS is a therapeutic method that modulates the membrane potential, where anodic stimuli induce cortical excitability and cathodic stimuli reduce it

No respondres placebo effect; Respondres placebo effect

a- tDCS DEVICE

\- Intervention: tDCS is a therapeutic method that modulates the membrane potential, where anodic stimuli induce cortical excitability and cathodic stimuli reduce it

No respondres placebo effect; Respondres placebo effect

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Women aged 18 to 65 years; who can read and write, with a confirmed diagnosis of FM according to the American College of Rheumatology criteria (2010-2016). Pain score equal to or greater than six on the Numerical Pain Scale (NPS 0-10) on most days of the last 3 months.

You may not qualify if:

• Residing outside the greater Porto Alegre area and pregnancy. Contraindications to TMS and tDCS: metallic implant in the brain; medical devices implanted in the brain, cardiac pacemakers; cochlear implant; history of alcohol or drug abuse in the last 6 months; neurological pathologies; hx of head trauma or neurosurgery; decompensated systemic diseases and chronic inflammatory diseases (lupus, rheumatoid arthritis, Reiter's syndrome); uncompensated hypothyroidism; personal history of cancer, past or undergoing treatment.

Sponsors & Collaborators

• Hospital de Clinicas de Porto Alegre: lead

Study Sites (1)

Hospital de Clinicas de Porto Alegre

Porto Alegre, Rio Grande do Sul, 90.450-120, Brazil

Location

Related Publications (4)

• Clauw DJ, Arnold LM, McCarberg BH; FibroCollaborative. The science of fibromyalgia. Mayo Clin Proc. 2011 Sep;86(9):907-11. doi: 10.4065/mcp.2011.0206.

  PMID: 21878603 BACKGROUND

• Keeser D, Meindl T, Bor J, Palm U, Pogarell O, Mulert C, Brunelin J, Moller HJ, Reiser M, Padberg F. Prefrontal transcranial direct current stimulation changes connectivity of resting-state networks during fMRI. J Neurosci. 2011 Oct 26;31(43):15284-93. doi: 10.1523/JNEUROSCI.0542-11.2011.

  PMID: 22031874 BACKGROUND

• Zanette SA, Dussan-Sarria JA, Souza A, Deitos A, Torres IL, Caumo W. Higher serum S100B and BDNF levels are correlated with a lower pressure-pain threshold in fibromyalgia. Mol Pain. 2014 Jul 8;10:46. doi: 10.1186/1744-8069-10-46.

  PMID: 25005881 BACKGROUND

• Caumo W, Franca BR, Orzechowski R, Bueno G, Franca de Souza A, Dos Santos da Silva JV, Sanches PRS, Da Silva DP Jr, Torres ILS, Hirakata VN, Pacheco-Barrios K, Fregni F. Home-Based Transcranial Direct Current Stimulation vs Placebo for Fibromyalgia: A Randomized Clinical Trial. JAMA Netw Open. 2025 Jun 2;8(6):e2514262. doi: 10.1001/jamanetworkopen.2025.14262.

  PMID: 40478572 DERIVED

MeSH Terms

Conditions

Fibromyalgia; Pain

Condition Hierarchy (Ancestors)

Muscular Diseases; Musculoskeletal Diseases; Rheumatic Diseases; Neuromuscular Diseases; Nervous System Diseases; Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Wolnei Caumo, PhD

  Hospital de Clinicas de Porto Alegre

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: The researcher will receive equipment already programmed by a research assistant, so the researcher who will deliver the tDCS to perform stimulation will not know the programed stimulation. Patients will be instructed to discuss aspects of treatment with the respective investigator. Two independent evaluators who will not participate in the consultations where guidance on the use of tDCS will be provided will be trained to make outcome assessments in follow-up. Patients will not be aware of the type of intervention received, since the sham condition produces a stimulus, but no expected effects. In order to study the level of the blinding, at each moment of evaluation, the patient will be asked about the type of intervention that he / she believes to have received (active or simulated), and about the degree of safety in the response, using a standardized questionnaire. The blinding will be evaluated at the end of each treatment week by means of a standardized instrument.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Double-Blind, Randomized, Parallel Group, Sham-Controlled Clinical Trial

Study Record Dates

• First Submitted: April 26, 2023
• First Posted: May 6, 2023
• Study Start: September 16, 2021
• Primary Completion: April 25, 2023
• Study Completion: June 20, 2024
• Last Updated: January 8, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

BR (1)