TDCS and Tele-rehabilitation Exercise in Fibromyalgia

Effects of Anodal TDCS Applied Over M1 and DLPFC Combined with a Telerehabilitation Exercise Program in Patients with Fibromyalgia: a Randomized Controlled Trial

This randomized controlled trial aims to analyze the effects of anodal tDCS applied over the primary motor cortex and dorsolateral prefrontal cortex combined with a tele-rehabilitation exercise program in patients with fibromyalgia. The study will compare these effects with each other and with placebo tDCS on the following variables: pain intensity, pain mechanosensitivity, quality of life, fatigue, anxiety, depression, sleep quality, pain catastrophizing, functional capacity, isometric strength, and exercise adherence.

Secondary objectives include:

• Describing the sociodemographic, clinical, and functional characteristics of fibromyalgia patients.
• Comparing exercise intensity levels between patients receiving tDCS on M1, DLPFC, and placebo stimulation.
• Reporting any adverse effects of the intervention. Adult participants with fibromyalgia will be randomized into three groups: a) anodal tDCS over M1 + telerehabilitation, b) anodal tDCS over DLPFC + telerehabilitation, and c) sham-tDCS + telerehabilitation. The intervention will last for 12 weeks. The telerehabilitation exercise program will include an aerobic phase and a resistance phase, with four intensity levels regulated based on the Borg Rating of Perceived Exertion (0-10). The program will be conducted remotely through phone contact, with materials and videos provided to guide exercise execution. tDCS will be applied once per week for 20 minutes at 2 mA, either over M1 or DLPFC.

The dependent variables-pain intensity, fibromyalgia impact, fatigue, anxiety and depression levels, pain catastrophizing, sleep quality, functional capacity, and isometric muscle strength-will be collected in the week prior to the intervention, the week following the intervention, and 12 weeks after its completion. Additionally, pain intensity, fibromyalgia impact, fatigue severity, anxiety and depression levels, pain catastrophizing, and sleep quality will be evaluated during the 6th week of the intervention.

Exercise intensity, exercise adherence, and any adverse effects related to the intervention will be recorded weekly.

Inclusion Criteria:

• Age between 30 and 70 years.
• Medical diagnosis of fibromyalgia.Compliance with the latest diagnostic criteria from the American College of Rheumatology.
• Stable medication for at least 12 weeks prior to the start of the study.
• Ability to use communication technologies, such as smartphones and computers.
• Capacity to participate in an aerobic exercise program.
• Access to the internet.
• Proficiency in oral and written Spanish.
• Signed informed consent

Exclusion Criteria:

• Severe psychiatric disorders.
• Uncontrolled cardiovascular, respiratory, metabolic, neurological, rheumatic, or hepatic diseases.
• Concurrent chronic inflammatory or autoimmune disease.
• Contraindications to physical activity.
• Metal implants in the head.
• History of cancer, brain tumor, epileptic episodes, stroke, severe head trauma, or brain surgery.
• Pregnancy or lactation.
• Use of carbamazepine in the past 6 months.
• Changes in medication during the study.
• Participation in other non-pharmacological conservative therapies (e.g., hydrotherapy, electrotherapy, manual therapy, exercise, dry needling) during the study.