Objective: Electrical stimulation of the vagus has proven effective in various inflammatory conditions in animal models. The aim of this study is to show the effect of vagal nerve neurostimulation on clinical and laboratory parameters in two patients with active rheumatoid arthritis (RA) and an inadequate response to methotrexate.
Patients and methods: The research was conducted as part of an international pilot study. Patients were implanted with the Cyberonics system for electrical stimulation of the vagus. After an initial in-clinic stimulation, the patients performed the stimulations at home for 42 days, when the device was inactivated. On day 56 the stimulations were reinitiated. The following parameters were evaluated: tender and swollen joint count, physician’s (PGA) and patient’s (PtGA) global score, intensity of pain, disease activity (DAS28), functional ability (HAQ), serum CRP level, and EULAR response.
Results: In the period from the screening visit to the day 42 visit, both patients experienced an improvement of DAS28 (7.00 and 6.22 vs. 4.03 and 2.13), PGA (70 and 53 vs. 27 and 16), PtGA (48 and 43 vs. 15 and 14), tender joint count (26 and 28 vs. 4 and 0), swollen joint count (24 and 14 vs. 8 and 2), intensity of pain (72 and 87 vs 21 and 7), HAQ score (2.25 and 2.25 vs. 1.5 and 1.375), and CRP levels (23.8 and 5.58 vs. 13 and 4.61). After the device deactivation, DAS28 and VAS pain worsened in both patients.
Conclusion: Vagal neural stimulation in the treatment of patients with active RA and an inadequate response to methotrexate is effective in reducing clinical symptoms and parameters of inflammation. Our results are in accordance with the results obtained in other centers. Research on a larger number of subjects is necessary for a better evaluation of the effect of this new approach to the treatment of patients with rheumatoid arthritis.