Incidence of COVID-19 in patients with rheumatic diseases treated with targeted immunosuppressive drugs: what can we learn from observational data?

Objectives: To describe the incidence and severity of coronavirus disease 2019 (COVID-19) in rheumatic patients treated with targeted synthetic or biological anti-rheumatic drugs (ts/bDMARDs) compared with the general population living in the same Italian region. Methods: Patients followed at two referral rheumatology centres in Lombardy from 25th February to 10th April 2020 were invited to participate in a survey to detect patients with confirmed COVID-19, close contacts with known COVID-19 cases, symptoms of infection, working, behavioural and disease management changes applied to prevent the contagion. The incidence of COVID-19 in the Lombardy population was obtained from the National Institute of Statistics. Confirmed COVID-19 was defined by nasopharyngeal swab. Results: The survey was circulated amongst 955 patients (531 rheumatoid arthritis, 203 psoriatic arthritis, 181 spondyloarthritis, and 40 of connective tissue diseases/vasculitides/autoinflammatory diseases; mean age 53.7 years; female: 67.4%). The rate of responders was 98.05%. The incidence of confirmed COVID-19 is consistent with the general population (0.62% vs 0.66%; p=0.92). None of the patients had severe complications or required intensive care treatment, and all of them temporarily discontinued ongoing ts/bDMARDs therapy. Almost all patients adopted precautions to prevent the contagion (90.6%) and maintained the ongoing treatment with ts/bDMARDs (93.2%). The disease activity remained stable in 89.5% of patients. Conclusions: Our results highlight the attitude from rheumatic patients to prevent the contagion while maintaining their chronic treatments. The incidence and severity of COVID-19 in patients treated with ts/bDMARDs was not significantly different from that of the general population in the same region.