Since the global emergence of SARS-CoV-2 at the end of 2019, a special concern has raised regarding patients with rheumatic and inflammatory diseases, such as systemic lupus erythematosus (SLE).1 Indeed, many treated patients with SLE are immunocompromised and often suffer from chronic kidney or cardiovascular diseases.2 Recently, anti-interferon antibodies have been implicated in severe SARS-CoV-2 infection3 while it has been known for decades that patients with SLE may produce such autoantibodies.4 Although available data from short SLE series are reassuring,5 6 large-scale nationwide studies are still needed to assess the risk of developing severe SARS-CoV-2 infection in SLE.

We therefore used the French healthcare database system called ‘Programme de Médicalisation des Systèmes d’Information’—which contains hospitalisation data of all inpatients in France—to analyse the population with SLE that had at least one stay in a French hospital between March and 30 October 2020 (online supplemental material). On this population, we compared inpatients with SLE with or without SARS-CoV-2 infection (SLE/COVID-19+, SLE/COVID-19). Among SLE/COVID-19+ inpatients, we distinguished patients with poor outcome after SARS-CoV-2 infection and patients with good outcome after COVID-19. We defined poor outcome as admission to intensive care unit (ICU) or death. We also compared the in-hospital mortality associated with SARS-CoV-2 infection in SLE and in the total population in France.