Characteristics of COVID-19 and Impact of Disease Activity in Patients with Adult-Onset Still's Disease.

Introduction: This study aimed to characterize the morbidity, hospitalization, and mortality rates among patients with adult-onset Still's disease (AOSD) affected by coronavirus disease 2019 (COVID-19) and explore the impact of COVID-19 on the disease activity of AOSD.

Methods: Data on the clinical and demographic characteristics, COVID-19-related symptoms, and outcomes were retrospectively collected. Patients were stratified according to COVID-19 severity and associations between risk factors and outcomes were analyzed using multivariate logistic regression. The disease activity of patients with AOSD flares after COVID-19 was described.

Results: A total of 188 patients with AOSD were followed up, of whom 75.5% (n = 142) had a confirmed or highly suspected COVID-19. Patients on medium or high-dose oral glucocorticoids or Janus kinase (JAK) inhibitors were at increased risk of developing moderate to severe COVID-19. Six patients suffered flares of AOSD following COVID-19 in a short period; however, the relapse rate was not statistically increased compared with patients without COVID-19.

Conclusion: Patients with AOSD receiving medium or high-dose glucocorticoid therapy or JAK inhibitors had worse COVID-19 outcomes. Further work is needed to explore risk factors affecting COVID-19 outcomes and the impact of COVID-19 on disease activity in AOSD.