Transcutaneous Vagus Nerve Stimulation on Fibromyalgia- Double-blind, Sham-controlled Randomized Clinical Trial

Summary

Stimulation of the vagus nerve, a parasympathetic nerve that controls the digestive, the vascular and immune systems, produces pain relief in various clinical conditions. Transmission via vagal afferents to the nucleus of the solitary tract has been proposed as the primary physiological mechanism that reduces pain intensity following vagal stimulation. Medication is one of the pillars of dealing with chronic pain, with several benefits, but also side effects. Fibromyalgia is an idiopathic chronic pain syndrome with few, effective and safe treatments. However, current research in the field of vagal innervation suggests psychophysiological and electrical ways by which the syndrome may be treated.The chronic pain symptoms of fibromyalgia patients may benefit from vagus nerve stimulation, by normalizing the autonomic and immune system dysfunction that causes their respective symptoms. However, the effects of multiple sessions of transcutaneous vagus nerve stimulation (tVNS) in fibromyalgia have not been evaluated in randomized clinical trials. The hypothesis of our study is to evaluate if the addition of transcutaneous stimulation of the auricular branch of the vagus nerves in patients with fibromyalgia, can lead to better pain control and quality of life. We will offer a 2-week treatment (14 sessions of 30 minutes) in a randomized double-blind controlled trial. The sample of the study, which will be conducted in the pain clinic of the Aretaieion University General Hospital, will be consisted of 120 patients, who will be divided into 2 groups (1st group: standard pharmacological treatment + active tVNS, 2nd group: standard pharmacological treatment + sham tVNS). The study is designed to determine, if standard pharmacological treatment combined with 14 sessions of tVNS is able to improve pain symptomatology in fibromyalgia and all symptoms of this syndrome, by using appropriate scales. This study examines a new and potentially impactful way to address a major public health issue where prevalence is high in given groups, its impact is multidimensional and treatment options are limited. The holistic treatment of chronic pain, including its neurobiological, cognitive, behavioral and psychological components, may become a valuable aid in the completion of the research project, with the ultimate aim of the study being the establishment of non-invasive stimulation of the vagus nerve for the treatment of chronic pain in clinical practice in the future.

Conditions

• Transcutaneous Vagus Nerve Stimulation on Fibromyalgia

Interventions

DEVICE

tVNS

tVNS L is a battery-driven electrical stimulator connected to an ear electrode which is positioned over the skin of the cymba conchae. Thus, auricular vagal stimulation will be applied using the typical ear electrodes of the tVNS® L device. tVNS will be applied over the left branch for safety reasons. For sham auricular tVNS, the anodal electrode will be placed over the center of the left ear lobe. The cathode will be placed over the antitragus. This method and these stimulation parameters have been previously used for reliable blinding in other clinical studies. Series of electrical pulses with 250 μs pulse width, 25 Hz frequency, and 28 s inter-burst interval (32 sec on/28 sec off duty cycle) will be applied in each intervention session. Auricular tVNS will be applied at 1mA - 5mA intensity for 30 min per session (1 session per day, 7 consecutive days a week, 14 sessions in total)

Sponsors & Collaborators

• National and Kapodistrian University of Athens

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

79 Years

Sex

FEMALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2024-10-15

Primary Completion

2026-06-01

Completion

2026-06-01

Countries

• Greece

Study Locations