The effectiveness of vagus nerve stimulation in rheumatoid arthritis: a systematic review

Objective: This review aims to assess the effectiveness of vagus nerve stimulation (VNS) in relieving RA symptoms.Methods: A systematic review was performed in seven databases to identify randomized clinical trials that investigated the use of VNS on the symptom improvement of adults with RA.The review adhered to PRISMA guidelines and assessed bias risk using the RoB 2.0 Tool.Results: A total of 1131 documents were identified, but only four were included.It was found no significant difference between active and sham stimulation in ACR20 response rates at week 12 (25.0%vs. 26.9%,p = 0.823), with similar results for Disease Activity Score 28 with C-reactive protein (DAS28-CRP) and HAQ-DI.However, high-disease activity participants showed significant reductions in DAS28-CRP, CRP levels, and interferon-y with non-invasive VNS (n-VNS), whereas low-disease activity participants did not benefit and experienced a decrease in cardiac vagal tone and interleukin-10 levels.Overall, n-VNS was well tolerated.VNS with a small neurostimulator was safe and effective in alleviating RA symptoms in drug-resistant patients.Two patients experienced significant improvements in various measures between the screening visit and day 42, but after device deactivation, they experienced worsened DAS28 and VAS pain scores.Conclusions: VNS was well-tolerated and yielded favorable results, indicating its potential as a viable treatment option.Its efficacy in treatment-resistant RA patients offers promising prospects.