Transcutaneous Vagus Nerve Stimulation as a Complementary Therapy to Exercise in Chronic Fatigue

Transcutaneous Vagus Nerve Stimulation as a Complementary Therapy to Exercise in Chronic Fatigue: Single-center, Controlled, Randomized, Blinded Study

Chronic fatigue is enhanced by adapted physical activity (APA) programs. Patients consulting on St Etienne hospital and suffering from fibromyalgia and long Covid benefit from a 4-6 week APA program, with 2 sessions per week. While most patients are improved by these exercise-training programs, for some the benefits remain very modest, and patients describe persistent fatigue. The literature unanimously describes the necessity of longer APA protocols (8-12 weeks, 2-3 sessions/week) for fatigue reduction in fibromyalgia and long Covid. However, it seems difficult to adhere to an optimal program as described in the literature for these fatigued patients. The investigators want to test a device that would both reduce fatigue and improve recovery between APA sessions, in order to gradually reach the recommendations for APA practice. Transcutaneous vagal nerve stimulation (tVNS) seems to be a promising approach. Thus, combining an APA intervention with a tVNS protocol could potentiate the expected and now well-known effect of exercise.

Inclusion Criteria:

• Patient over 18 years old
• Signature of informed consent
• Confirmed diagnosis of fibromyalgia or long Covid (ACR 2016 criteria and persistent symptoms lasting more than 6 months after a positive RT-PCR test, respectively)
• Persistent fatigue after an exercise rehabilitation program (FSS score > 36)
• Physical inactivity, i.e. <150 minutes per week of physical activity

Exclusion Criteria:

• Pre-existing atrial fibrillation,
• Left ventricular ejection fraction <40%
• Severe heart failure
• Recent stroke or myocardial infarction (<6 months)
• Unilateral or bilateral vagotomy
• Pregnancy or breastfeeding