Objective: To investigate the effect of antimalarials on cancer risk in patients with systemic lupus erythematosus (SLE).
Methods: PubMed, EMBASE, Web of Science, and the Cochrane Library were searched from their inception to October 3, 2020. Relative risk (RR) with 95% confidence intervals (CI) was used to evaluate the results. Subgroup analyses were used to assess heterogeneity. A funnel plot was used to explore publication bias. STATA was applied for all analyses.
Results: A total of nine studies consisted of four nested case-control, two case-cohort and three cohort studies were included. The results showed that antimalarials might reduce the risk of cancer in SLE (RR = 0.68, 95%CI: 0.55-0.85). In the subgroup analysis of four nested case-control and two case-cohort studies, the pooled RR was estimated as 0.69 (95% CI: 0.60-0.80). In four studies about hydroxychloroquine, the pooled RR was estimated as 0.70 (95% CI: 0.53-0.93). Antimalarials might reduce the risk of cancer in SLE among the Asian population (RR = 0.66; 95% CI: 0.49-0.88) (I2 = 43.1%, p = .173). And the consistent result was also found in SLE from multiple centres (RR = 0.72; 95%CI: 0.60-0.87) (I2 = 0%, p = .671). On disease course- and comorbidities-matched studies, the pooled RRs were 0.69 (95% CI: 0.52-0.93) and 0.59 (95% CI: 0.46-0.75), respectively.
Conclusion: Results of this meta-analysis showed that antimalarial drugs might be protective factors for cancer in SLE. Hydroxychloroquine might be a protective factor for cancer in SLE patients.KEY MESSAGESAntimalarials might be protective factors for cancer in SLE.Hydroxychloroquine might be a protective factor for cancer in SLE patients.The first article to perform the meta-analysis of antimalarial drugs on the risk of cancer in SLE patients.
Keywords: Systemic lupus erythematosus; antimalarials; cancer; hydroxychloroquine.