The efficacy of moxibustion on the pressure pain threshold and substance P / leukotriene B4 contents in serum to patients with rheumatoid arthritis

Abstract

Objective

To observe the effects of moxibustion on pressure-pain thresholds (PPTs) in affected joints and non-joint areas, as well as the contents of substance P (SP) and leukotriene B4 (LTB4) in serum of patients with rheumatoid arthritis (RA), and to explore the analgesic mechanism of moxibustion in RA patients.

Methods

A total of 72 patients with RA were randomly and equally classified into the control and treatment groups. The control group was treated with routine drug therapy, while the treatment group received routine drug therapy and moxibustion. Both groups were treated for 8 weeks. The symptoms, measured by PPTs, Visual analogue scale (VAS), pain joint count (PJC), swollen joint count (SJC) and disease activity score of 28 joints (DAS28), and laboratory indicators, measured by the level of SP, LTB4, tumor necrosis factor- α (TNF-α) and interleukin-1β (IL-1β), were compared in the two groups before and after intervention.

Results

A total of 66 patients completed the trial, with 1 patients dropping out from the treatment group and 5 patients being excluded and dropped from the control group. Trial endpoints were change (∆) in symptoms and laboratory indicators. The treatment group showed superior in ∆PPTs of the interphalangeal joints(1301.71 (95 %CI, 967.43–1636.00) vs 443.23(95 %CI, 99.51–786.95)), ∆SP(10.11 (95 %CI, 5.85–14.37) vs 3.10 (95 %CI, −1.13–7.34)), ∆ LTB4(13.17 (95 %CI, 7.81–18.54) vs 3.37 (95 %CI, −5.73–12.48)), ∆TNF-α(4.57 (95 %CI, 2.60–6.55) vs 0.68 (95 %CI, −1.03–2.40)), ∆IL-1β(4.63 (95 %CI, 2.59–6.66) vs 1.63 (95 %CI, −0.53–3.80)), ∆PJC(7.14 (95 %CI, 5.17–8.58) vs 1.84 (95 %CI, 0.66–3.02)), ∆SJC(5.20 (95 %CI, 3.44–6.96) vs 1.00(95 %CI, 0.02–1.98)), ∆VAS(3.6 (95 %CI, 2.99–4.21) vs 0.9 (95 %CI, 0.24–1.57)), and ∆DAS(1.68 (95 %CI, 1.44–1.92) vs 0.41 (95 %CI, 0.08–0.73)) compared to the control group, at weeks 4. Furthermore, there was a significant negative correlation between ∆PPTs of the interphalangeal joints and ∆SP in the treatment group (r < 0, P < 0.05).

Conclusion

Moxibustion combined with conventional western medicine can significantly improve PPTs in affected joints of RA patients, alleviate clinical symptoms, and reduce disease activity. The potential mechanism may be related to the down-regulation of SP and LTB4 levels and the reduction of the release of inflammatory factors Il-1β and TNF-α by moxibustion. The lack of double-blinding is a limitation of our study, which we plan to avoid by establishing a sham moxibustion group in the subsequent trials.