LAUSR

Objectives: To investigate the association of severe COVID-19 in those with inflammatory rheumatic diseases (IRD) treated with different immunosuppressive therapies including 4663 individuals on biologics and targeted synthetic DMARDs. Methods: A list of IRD patients on biologics and targeted synthetic (ts) DMARDs in March 2020 was linked to the REACT-SCOT study, an incidence density-sampled case-control study that includes all new cases of COVID-19 diagnosed in Scotland since the start of the pandemic, linked to electronic health records including all prescribing in primary care. Main outcome measure: Hospitalised or fatal COVID-19 . Results: By 22 November 2021 433 of the 4633 patients treated with biologics and tsDMARDs had been diagnosed with COVID-19, of whom 58 had been hospitalised and 14 died within 28 days. With all those in the population not on DMARDs as reference category, the rate ratio for hospitalised COVID-19 associated with DMARD treatment was 2.14 (95% CI 2.02 to 2.26) in those on conventional synthetic (cs) DMARDs, 2.01 (95% CI 1.38 to 2.91) in those on TNF inhibitors as the only biologic agent, and 3.83 (95% CI 2.65 to 5.56) in those on other biologic agents. Among those on csDMARDs, rate ratios for hospitalised COVID-19 were lowest at NA in those on methotrexate and highest at 5.4 (95% CI 4.4 to 6.7) in those on glucocorticoids at average dose equivalent to >10 mg/day prednisolone. Conclusion: The risk of hospitalised COVID-19 is elevated in IRD patients treated with immunosuppressive drugs. Of these drugs, methotrexate, hydroxychloroquine, and TNF inhibitors carry the lowest risk; JAK inhibitors and B-cell depleting agents a higher risk and prednisolone the highest risk. This information should be taken into account in selecting the most appropriate immunosuppressive therapy for patients with IRD, but more a larger study is needed to estimate reliably the risks associated with each class of biologic agent.