Development of SARS-CoV-2 infection in patients with rheumatic conditions on hydroxychloroquine monotherapy vs. patients without rheumatic conditions: A retrospective, propensity-matched cohort study

The primary purpose of the current study was to examine whether patients with rheumatologic conditions receiving only chronic hydroxychloroquine therapy for their disease are at less risk of developing SARS-CoV-2 infection than a comparative group of patients without rheumatologic conditions. A retrospective, observational, nationwide stratified propensity analysis was conducted comparing patients only on chronic treatment with hydroxychloroquine for their rheumatologic condition to a random sample of patients without rheumatologic conditions and not receiving hydroxychloroquine, utilizing a Veterans Health Administration nationwide clinical administrative database. The 1-to-1 stratified propensity analysis was undertaken using a random sample of patients without rheumatoid conditions and not receiving hydroxychloroquine (n 33,081) and patients with rheumatoid conditions receiving hydroxychloroquine as the lone medication for their condition (n 6047). A total of 5,474 patients in each group were successfully matched. The incidence of documented SARS-CoV-2 infections during the study period did not differ between patients receiving hydroxychloroquine and patients not receiving hydroxychloroquine (41/5,474 [0.749%] vs. 36/5,474 [0.658%], respectively, p = 0.57; Odds ratio [OR] 1.14, 95% confidence interval [CI] 0.73-1.79). There were no statistically-significant differences in secondary outcomes between the two groups in patients who developed active SARS-CoV-2 infection. Multivariate logistic regression to determine independent variables associated with the development of active SARS-CoV-2 infection failed to include receipt of hydroxychloroquine (OR 0.99, 95% CI 0.62-1.56). Hydroxychloroquine failed to demonstrate a preventative effect against SARS-CoV-2 infection in a large group of patients with rheumatologic conditions compared to patients without rheumatologic conditions.