The Efficacy and Safety of Hydroxychloroquine in Patients with COVID-19: A Multicenter National Retrospective Cohort

Introduction Hydroxychloroquine (HCQ) is an antimalarial drug that received worldwide news and media attention in the treatment of patients with coronavirus disease 2019 (COVID-19). This drug was used on the basis of its antimicrobial and antiviral properties despite lack of definite evidence of clinical efficacy. In this study, we aim to assess the efficacy and safety of using HCQ in treatment of patients with COVID-19 who were admitted in acute care hospitals in Bahrain. Methods We conducted a retrospective cohort study on a random sample of patients admitted with COVID-19 between 24 February and 31 July 2020. The study was conducted in four acute care COVID-19 hospitals in Bahrain. Data was extracted from the medical records. The primary endpoint was the requirement of non-invasive ventilation, intubation, or death. Secondary endpoint was length of hospitalization for survivors. Three methods of analysis were used to control for confounding factors: logistic multivariate regression, propensity score adjusted regression, and matched propensity score analysis. Results A random sample of 1571 patients were included, 440 of whom received HCQ (treatment group) and 1131 did not receive it (control group). Our results showed that HCQ did not have a significant effect on primary outcomes due to COVID-19 infection when compared to controls after adjusting for confounders (OR 1.43, 95% CI 0.85-2.37, P = 0.17). Co-administration of azithromycin had no effect on primary outcomes (OR 2.7, 95% CI 0.82-8.85, P = 0.10). HCQ was associated with increased risk of hypoglycemia (OR 10.9, 95% CI 1.72-69.49, P = 0.011) and diarrhea (OR 2.8, 95% CI 1.4-5.5, P = 0.003), but not QT prolongation (OR 1.92, 95% CI 0.95-3.9, P = 0.06) or cardiac arrhythmia (OR 1.06, 95% CI 0.55-2.05, P = 0.85). Conclusion Our results showed no significant beneficial effect of using hydroxychloroquine on the outcome of patients with COVID-19. Moreover, the risk of hypoglycemia due to hydroxychloroquine would possess a significant risk for out-of-hospital use.