A randomized, double-blind, sham-controlled study of static electric field therapy by high voltage alternating current for active rheumatoid arthritis

Static electric field therapy by high voltage alternating current (EF-HVAC) is a traditional complementary Japanese medicine used for headache, shoulder stiffness, chronic constipation and insomnia. Open-label studies and clinical experience in Japan have suggested that this electric field therapy is safe and effective in treating chronic arthritis. We evaluated the efficacy of EF-HVAC therapy in a randomized, double-blinded, sham-controlled trial in patients with active rheumatoid arthritis (RA) in community-based general physician centers. Thirty patients fulfilling American College of Rheumatology (ACR) criteria for RA were treated with EF-HVAC therapy with the LEGACIS PLUS System (COCOROCA Corp., Tokyo, Japan) or sham therapy for 12 weeks and followed for 4 weeks without treatment. The disease activity score 28 (DAS28-CRP), visual analogue scale for pain (VAS), modified health assessment questionnaire (MHAQ), and inflammatory parameters were used as the outcome variable. Twenty four patients (n = 12 in each group) were analyzed by a per protocol analysis. Although a significant reduction in DAS28-CRP was observed in EF-HVAC group at 8 and 12 weeks compared to before treatment, there were no significant differences in DAS28-CRP scores during treatment between two groups. The scale of VAS was also significantly decreased by the treatment with EF-HVAC compared to before treatment, in addition, the scale of VAS in EF-HVAC group was significantly lower than sham group at 8 and 12 weeks. Changes in another parameters including MHAQ were not significant between before and after treatment, or by all comparative study between two groups. There were no adverse events related the treatment. In conclusion, the EF-HVAC therapy has a beneficial effect on the improvement to subjective pain of RA.