The efficacy of statins in the treatment of rheumatoid arthritis: A systematic review and meta-analysis

BACKGROUND: A large body of research has investigated the use of statins in rheumatoid arthritis (RA); however, the therapeutic effects of statins remain uncertain. Thus, we designed a systematic review and meta-analysis to evaluate the role of statins in patients with RA. METHODS: Databases searched to detect clinical randomized controlled trials or clinical controlled trials on the interaction between statins and RA before January 2020 included PubMed, Web of Sciences, Embase, Cochrane Library, CNKI, Wan Fang Database. Efficacy was measured by Disease Activity Score in 28 Joints (DAS28), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), tenderness of the joint (TJ), swelling of the joint (SJ), and interleukin-6. The level of blood lipid was also evaluated. STATA 12.0 was used for the meta-analysis. The Cochrane method was used for quality assessment. Heterogeneity was considered to determine fixed effects or random effects models. RESULTS: Nineteen clinical trials with a total of 22,906 subjects were included in the meta-analysis. Sixteen studies reported a change in DAS28 after statin treatment. The pooled analysis showed that statins reduced DAS28 in RA patients. Change in ESR after statin treatment was reported in 9 studies. The summary analysis showed that statins lowered ESR in RA patients. Twelve studies reported a change in CRP after statin treatment. The results of the entire analysis showed that statins lowered CRP in RA patients. Seven studies reported a change in TJ after statin treatment. The combined analysis showed that statins reduced TJ at RA patients. Six studies reported changes in IL6 after statin therapy. The results showed that statins failed to reduce IL6 in RA patients. Seven studies reported changes in SJ after statin therapy, which showed that statins failed to reduce SJ in RA patients. We also found that statins can reduce blood lipid levels in RA patients. CONCLUSION: In conclusion, statins were able to reduce DAS28, ESR, CRP, TJ, and blood lipids. It indicated that stains can benefit patients with RA by inhibiting the expression of inflammatory factors and reducing the levels of lipids in the blood. Our study may offer a new perspective on the treatment of RA and provide research ideas for future larger multi-center clinical trials.