Auricular vagus nerve stimulation of little benefit in rheumatoid arthritis

Auricular vagus nerve stimulation (VNS) does not appear to be efficacious at managing disease activity in individuals with rheumatoid arthritis (RA), as reported in a study.

Conducted to address the limited evidence on the benefit of VNS in RA, the study included 113 adults (mean age 54 years, 82 precent women) with active RA who had inadequate response to conventional synthetic disease-modifying antirheumatic drugs (DMARDs) and were naïve to biologic and/or targeted synthetic DMARDs.

The participants received an auricular vagus nerve stimulator device and were randomly assigned to undergo either active stimulation or sham stimulation.

The primary endpoint was the proportion of patients achieving a 20-percent improvement in American College of Rheumatology criteria (ACR20) at week 12. Secondary endpoints were mean changes in disease activity score of 28 joints with C-reactive protein (DAS28-CRP) and Health Assessment Questionnaire-Disability Index (HAQ-DI).

Of the participants, 101 (89.4 percent) completed the study. ACR20 response at week 12 did not significantly differ between the active and sham stimulation groups (25.0 percent vs 26.9 percent, respectively; difference, −1.9, 95 percent confidence interval [CI], −18.8 to 14.9; p=0.823).

The same was true for the secondary endpoints, with no significant between-group difference seen in the least square mean change in DAS28-CRP (−0.95 vs −0.66; p=0.201) and in HAQ-DI (−0.19 vs −0.02; p=0.044).

Seventeen patients (15 percent) had adverse events, all of which were mild or moderate in severity.