The association between hydroxychloroquine treatment and cardiovascular morbidity among rheumatoid arthritis patients

Objectives: To examine the independent effect of hydroxychloroquine (HCQ) treatment on cardiovascular morbidity among RA patients. Materials and Methods: A retrospective cohort study of RA patients treated at Meir medical center between 2003-2013 was conducted. Patients were divided into two groups, those who had been treated with HCQ during the course of their disease and those who had never received it. The two groups were compared for possible confounding factors. Study endpoints included arterial and venous thrombotic events. Results: A total of 514 suitable RA patients were identified, 241 HCQ-treated and 273 non-treated patients. Of the HCQ-treated patients, 32 (13.3%) suffered from cardiovascular events compared to 104 (38.1%) of the non-treated group. HCQ treatment had a significant protective effect for all cardiovascular events examined (HR = 0.456 CI 0.287 to 0.726) as well as arterial events alone (HR = 0.461 CI 0.274 to 0.778). A dose of 400 mg HCQ per day demonstrated a protective effect for any cardiovascular event (HR = 0.432 CI 0.243 to 0.768), while the lower dose of 200 mg per day showed no significant protective effect. Conclusions: The use of HCQ is independently associated with decreased risk for cardiovascular morbidity among RA patients, particularly with a higher dose of 400 mg per day. This newly demonstrated effect of HCQ should be considered in the overall management of RA.