Effects of Transcutaneous Auricular Vagus Nerve Stimulation on Symptom Severity, Sleep Quality, Central Sensitization, and Kinesiophobia in Fibromyalgia

NCT07173400 | Completed

• 1 other identifier: E-10840098-202.3.02-4945 (30/0
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

Fibromyalgia is a chronic condition characterized by widespread musculoskeletal pain, fatigue, sleep disturbances, and sensitivity to touch. Current treatments often provide only partial relief. This study evaluates a non-invasive technique called transcutaneous auricular vagus nerve stimulation (TaVNS), which delivers gentle electrical impulses to a part of the ear connected to the vagus nerve. The vagus nerve plays an important role in regulating pain, stress, and autonomic body functions such as sleep. In this randomized controlled pilot trial, participants with fibromyalgia are assigned to receive either active TaVNS or sham (placebo) stimulation for 30 minutes per day, five days per week, over a four-week period. Participants are followed for a total of 8 weeks. The investigators will assess outcomes including pain intensity, sleep quality, central sensitization, and fear of movement (kinesiophobia).

Conditions

Fibromyalgia (FM); Chronic Pain

Keywords

Vagal Nerve Stimulation; fibromyalgia; pain; chronic pain

Outcome Measures

Primary Outcomes (3)

• Fibromyalgia Impact Questionnaire (FIQ)

  The FIQ evaluates the overall health status and functional impact of fibromyalgia, including physical functioning, pain, fatigue, and mood. Scores range from 0 to 100, with higher scores reflecting greater disease impact.

  Baseline, Week 2, Week 4, Week 8

• Pittsburgh Sleep Quality Index (PSQI)

  The PSQI is a validated self-report questionnaire that assesses subjective sleep quality and disturbances over the past month. Scores range from 0 to 21, with higher scores indicating poorer sleep quality.

  Baseline, Week 2, Week 4, Week 8

• Central Sensitization Inventory (CSI)

  The CSI is a 25-item self-report questionnaire assessing symptoms related to central sensitization, including sensitivity to pain, fatigue, and cognitive complaints. Scores range from 0 to 100, with higher scores indicating greater sensitization.

  Baseline, Week 2, Week 4, Week 8

Secondary Outcomes (2)

• Tampa Scale for Kinesiophobia (TSK)

  Baseline, Week 2, Week 4, Week 8

• Visual Analog Scale (VAS) for Pain

  Baseline, Week 2, Week 4, Week 8

Study Arms (2)

Active TaVNS

EXPERIMENTAL

Participants received active transcutaneous auricular vagus nerve stimulation (TaVNS) using the VagusStim® device (Vagus Medical Technologies, Istanbul, Türkiye). The electrode was placed on the left cymba concha and stimulation was applied for 30 minutes per day, 5 days per week, over 4 weeks (20 sessions). Stimulation parameters included 1-30 Hz frequency, 50-250 μs pulse width, and current individually adjusted (0.1-36 mA) to each participant's sensory threshold.

Device: Active Transcutaneous Auricular Vagus Nerve Stimulation (TaVNS)

Sham TaVNS

PLACEBO COMPARATOR

Participants underwent sham stimulation using the same VagusStim® device under identical conditions. The electrode was placed on the left earlobe, an area without vagal innervation, and sessions lasted 30 minutes per day, 5 days per week, for 4 weeks. No effective vagus nerve stimulation was delivered, maintaining participant blinding.

Device: Sham Transcutaneous Auricular Vagus Nerve Stimulation

Interventions

Active Transcutaneous Auricular Vagus Nerve Stimulation (TaVNS) DEVICE

Active TaVNS delivered with the VagusStim® device (Vagus Medical Technologies, Istanbul, Türkiye). The bipolar electrode was placed on the left cymba concha. Stimulation was applied for 30 minutes per day, 5 days per week, for 4 weeks (20 sessions). Parameters included frequency 1-30 Hz, pulse width 50-250 μs, and current intensity individually adjusted (0.1-36 mA) to the participant's sensory threshold.

Active TaVNS

Sham Transcutaneous Auricular Vagus Nerve Stimulation DEVICE

Sham stimulation delivered with the same VagusStim® device under identical conditions. The electrode was rotated and placed on the left earlobe, which lacks vagal innervation. Sessions lasted 30 minutes per day, 5 days per week, for 4 weeks (20 sessions). No effective vagus nerve stimulation was delivered, preserving participant blinding.

Sham TaVNS

Eligibility Criteria

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

You may qualify if:

• Age between 18 and 65 years
• Diagnosis of fibromyalgia according to the 2016 revised ACR criteria
• Receiving stable pharmacological and/or non-pharmacological treatment for at least 3 months
• Ability to understand study procedures and provide informed consent

You may not qualify if:

• Pregnancy
• History of epilepsy or cardiac arrhythmia
• Acute or chronic infection
• Heart failure (NYHA class II-IV)
• Renal failure stage II or higher
• Active malignancy
• Psychotic disorders or current psychiatric treatment
• Diagnosis of immune-mediated rheumatic disease

Sponsors & Collaborators

• Hatice Betigul Meral: lead

Study Sites (1)

Istanbul Medipol University, Faculty of Medicine, Department of Physical Medicine and Rehabilitation

Istanbul, Bagcılar, 34815, Turkey (Türkiye)

Location

Related Publications (4)

• Paccione CE, Stubhaug A, Diep LM, Rosseland LA, Jacobsen HB. Meditative-based diaphragmatic breathing vs. vagus nerve stimulation in the treatment of fibromyalgia-A randomized controlled trial: Body vs. machine. Front Neurol. 2022 Nov 3;13:1030927. doi: 10.3389/fneur.2022.1030927. eCollection 2022.

  PMID: 36438970 RESULT

• Abdel-Baset AM, Abdellatif MA, Ahmed HHS, El Shaarawy NK. Pain neuroscience education versus transcutaneous vagal nerve stimulation in the management of patients with fibromyalgia. Egypt Rheumatol. 2023;45:191-195. doi:10.1016/j.ejr.2023.03.001.

  RESULT

• Kutlu N, Ozden AV, Alptekin HK, Alptekin JO. The Impact of Auricular Vagus Nerve Stimulation on Pain and Life Quality in Patients with Fibromyalgia Syndrome. Biomed Res Int. 2020 Feb 28;2020:8656218. doi: 10.1155/2020/8656218. eCollection 2020.

  PMID: 32190684 RESULT

• Turk Kalkan T, Tarakci D, Kilic G, Celikyurt C. Investigation of the Effectiveness of Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) and Vestibular Rehabilitation in Patients with Unilateral Vestibular Hypofunction. Medicina (Kaunas). 2025 May 9;61(5):872. doi: 10.3390/medicina61050872.

  PMID: 40428830 RESULT

MeSH Terms

Conditions

Fibromyalgia; Chronic Pain; 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 Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: Participants and outcome assessors were blinded to group allocation. The treating clinician who applied stimulation was aware of assignment but did not participate in outcome assessment
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Principal Investigator

Model Details: This study used a two-arm, randomized, sham-controlled, parallel group design with a 1:1 allocation ratio

Study Record Dates

• First Submitted: September 5, 2025
• First Posted: September 15, 2025
• Study Start: August 1, 2025
• Primary Completion: October 10, 2025
• Study Completion: October 10, 2025
• Last Updated: January 15, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)