To examine the frequency of, and risk factors for, disease flare following COVID-19 vaccination in patients with systemic rheumatic disease (SRD).
An international study was conducted from April 2 to August 16, 2021, using an online survey of 5619 adults with SRD for adverse events following COVID-19 vaccination, including flares of disease requiring a change in treatment. We examined risk factors identified a priori based on published associations with SRD activity and SARS-CoV-2 severity, including demographics, SRD type, comorbidities, vaccine type, cessation of immunosuppressive medications around vaccination, and history of reactions to non-COVID-19 vaccines, using multivariable logistic regression.
Flares requiring a change in treatment following COVID-19 vaccination were reported by 4.9% of patients. Compared with rheumatoid arthritis, certain SRD, including systemic lupus erythematosus (OR 1.51, 95%CI 1.03, 2.20), psoriatic arthritis (OR 1.95, 95%CI 1.20, 3.18), and polymyalgia rheumatica (OR 1.94, 95%CI 1.08, 2.48) were associated with higher odds of flare, while idiopathic inflammatory myopathies were associated with lower odds for flare (OR 0.54, 95%CI 0.31-0.96). The Oxford-AstraZeneca vaccine was associated with higher odds of flare relative to the Pfizer-BioNTech vaccine (OR 1.44, 95%CI 1.07, 1.95), as were a prior reaction to a non-COVID-19 vaccine (OR 2.50, 95%CI 1.76, 3.54) and female sex (OR 2.71, 95%CI 1.55, 4.72).
SRD flares requiring changes in treatment following COVID-19 vaccination were uncommon in this large international study. Several potential risk factors, as well as differences by disease type, warrant further examination in prospective cohorts.

Published by Oxford University Press 2022.

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