Prophylactic effects of hydroxychloroquine on the incidence of COVID-19 in patients with rheumatic arthritis: an observational cohort study

Introduction: Rheumatoid arthritis (RA) is a systemic autoimmune disease with substantial morbidity and mortality. Anti-malarial drugs like hydroxychloroquine are indicated in several rheumatic diseases such as RA. Some reports have suggested hydroxychloroquine for prevention of COVID-19. Objectives: Whether hydroxychloroquine has prophylactic effects for COVID-19 in rheumatic patients. Patients and Methods: In this multicenter cohort-based observational study the preventive effect of hydroxychloroquine regarding the incidence and severity of COVID-19 was investigated in patients with RA who referred to rheumatology clinics of academic hospitals of Isfahan between April and July 2020 and already have been treated with hydroxychloroquine for more than three months. Around 215 patients with RA and current use of hydroxychloroquine were recruited and followed for three months. Patients’ information was gathered using the medical record or by phone call. Results: The incidence of COVID-19 in this selected sample was 4.2% (n=9). Only one in nine patients needed hospitalization, without need for intubation or ICU care. Symptoms including dry cough, headache, body pain, malaise, dyspnea, fever, sore throat, chills, and chest pain, were reported to be statistically higher in COVID-19+ group. Conclusion: In contrast to the mortality rate in the general population of Isfahan, Iran (4.8% - until June 2020), no mortality has been reported in these patients. Therefore, it seems that the use of hydroxychloroquine has been able to reduce the incidence and severity of the disease after reaching steady-state levels. This finding has clinical importance, especially for rheumatic patients using immunomodulatory drugs.