Chloroquine and hydroxychloroquine are associated with reduced cardiovascular risk: a systematic review and meta-analysis.

Background and aims: Chloroquine (CQ) and hydroxychloroquine (HCQ) are widely used in patients with rheumatic diseases, but their effects on the cardiovascular system remain unclear. We aimed to assess whether CQ/HCQ could reduce the risk of cardiovascular disease (CVD).

Materials and methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Embase, and the ClinicalTrials.gov for studies investigating the association between CQ/HCQ and the risk of CVD from inception to 20 December 2017. We carried out the quality assessment using the Newcastle-Ottawa Quality Assessment Scale (NOS). Random-effects model was used to pool the risk estimates relative ratio (RR), hazard ratio (HR) or odds ratio (OR) with 95% confidence interval (CI) for the outcomes.

Results: A total of 19 studies (7 case-control studies, 12 cohort studies, and no clinical trials) involving 19,679 participants were included in the meta-analysis. Pooled results for HRs or RRs showed that CQ/HCQ was associated with a significantly reduced risk of CVD (pooled RR 0.72, 95% CI 0.56-0.94, p =0.013). Results based on ORs showed a similar tendency towards a reduced risk of CVD with CQ/HCQ (pooled OR 0.41, 95% CI 0.25-0.69, p =0.001).

Conclusion: Our results suggested that CQ/HCQ was associated with a reduced risk of CVD in patients with rheumatic diseases. Randomized trials are needed to confirm the potential of CQ/HCQ in cardiovascular prevention in patients with and without rheumatic diseases.