Clinical characteristics of COVID-19 patients with underlying rheumatic diseases in Japan: data from a multicenter observational study using the COVID-19 Global Rheumatology Alliance physician-reported registry

INTRODUCTION: To describe clinical characteristics of patients in Japan with coronavirus disease 19 (COVID-19) and pre-existing rheumatic disease and examine the possible risk factors associated with severe COVID-19. METHODS: Adults with rheumatic disease and a COVID-19 diagnosis who were registered in the COVID-19 Global Rheumatology Alliance (C19-GRA) physician-reported registry from Japan between 15 May 2020 and 12 May 2021 were included. Multivariable logistic regression models were used to assess factors associated with severe COVID-19 progression, defined as death or requiring oxygen inhalation. RESULTS: In total, 222 patients were included in the study. Rheumatoid arthritis (48.2%), gout (14.4%), and systemic lupus erythematosus (8.1%) were the most common types of rheumatic disease, 55.1% of patients were in remission and 66.2% had comorbid disease. Most patients were hospitalised (86.9%) for COVID-19, 43.3% received oxygen, and 9.0% died. Older age (≥ 65 years), corticosteroid use, comorbid diabetes, and lung diseases are associated with higher risk for severe COVID-19 progression (odds ratio (OR) 3.52 [95% confidence interval (CI) 1.69–7.33], OR 2.68 [95% CI 1.23–5.83], OR 3.56 [95% CI 1.42–8.88], and OR 2.59 [95% CI 1.10–6.09], respectively). CONCLUSIONS: This study described clinical characteristics of COVID-19 patients with rheumatic diseases in Japan. Several possible risk factors for severe COVID-19 progression were suggested. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10067-022-06305-w.