Hydroxychloroquine use reduces mortality risk in systemic lupus erythematosus: A systematic review and meta-analysis of cohort studies

Objective Hydroxychloroquine (HCQ) is widely used in patients with systemic lupus erythematosus (SLE), but its effects on the mortality have not reached a definite conclusion. In this systematic review and meta-analysis, we aimed to assess whether HCQ use could reduce the risk of mortality in SLE patients. Methods PubMed, Embase, Web of Science, and Cochrane database were searched from inception to April 17, 2022 without language restrictions to explore the relationship between HCQ use and SLE mortality. The relative risk (HR) was pooled using the STATA software. Results A total of 21 studies with a pooled patient population of 26,037 were included in the study, including 14 studies on the association between HCQ alone and mortality risk and seven studies on the association between HCQ/chloroquine (CQ) and mortality risk. The pooled findings suggested that HCQ significantly reduced the overall mortality risk of SLE (pooled HR 0.46, 95% CI 0.38–0.57, p < 0.001). In subgroup analysis of SLE complications, HCQ use also decreased the risk of death in SLE patients with renal (HR=0.43, 95% CI 0.26–0.70, p = 0.001) and cardiopulmonary involvement (HR=0.37, 95% CI= 0.25–0.54, p < 0.001). In addition, HCQ use was also protective against the risk of mortality in SLE patients in different regions, such as Asia (HR=0.46, 95% CI=0.33–0.64, p < 0.001), Europe (HR= 0.40, 95% CI = 0.22–0.71, p = 0.002), and America (HR=0.52, 95% CI= 0.42–0.64, p < 0.001). Conclusion Our data suggested that HCQ use was associated with a reduced risk of mortality in patients with SLE.