Objectives: To compare the impact of COVID-19 on clinical status and psychological condition in patients with immune-mediated rheumatic diseases (IMRD) infected by SARS-CoV-2 with IMRD controls not infected, during a 6-month follow-up. Methods: The ReumaCoV Brasil is a longitudinal study designed to follow-up IMRD patients for 6 months after COVID-19 (cases) compared with IMRD patients no COVID-19 (controls). Clinical data, disease activity measurements and current treatment regarding IMRD, and COVID-19 outcomes were evaluated in all patients. Disease activity was assessed through validated tools at inclusion and at 3 and 6 months post-COVID-19. The FACIT-F (Functional Assessment of Chronic Illness Therapy) and DASS 21 (Depression, Anxiety and Stress Scale - 21 Items) questionnaires were also applied at 6 months after COVID-19 in both groups before large-scale vaccination. The significance level was set as p<0.05, with a 95% confidence interval. Results: A total of 601 patients were evaluated, being 321 cases (IMRD COVID-19+) and 280 controls (IMRD COVID-19 -), predominantly female with similar median age. No significant differences were noted in demographic data between the groups, including comorbidities, disease duration, and IMRD. Disease activity assessment over a 6-month follow-up showed no significant difference between cases and controls. While mean activity scores did not differ significantly, some patients reported worsened disease activity post-COVID-19, particularly in rheumatoid arthritis (RA) (32.2%) and systemic lupus erythematosus (SLE) (23.3%). Post-COVID-19 worsening in RA patients correlated with medical global assessment (MGA) and CDAI scores, with a moderate to large effect size. Diabetes mellitus showed a positive association (OR=7.15), while TNF inhibitors showed a protective effect (OR=0.51). Comparing SLEDAI pre- and post-COVID-19, a minority showed increased scores, with few requiring treatment changes. Fatigue, depression, anxiety, and stress were significantly higher in cases compared to controls. Worsening disease activity post-COVID correlated with worsened FACIT-F and DASS-21 stress scale in RA patients. No significant associations were found between COVID-19 outcomes and post-COVID-19 disease activity or psychological assessments. Conclusions: Post-COVID-19 IMRD patients show significant psychological well-being deterioration despite similar disease activity scores. The variability in reports on IMRD flares and the potential trigger of SARS-CoV-2 for autoimmune manifestations underline the need for detailed clinical assessment and a comprehensive approach to managing them.

The authors have declared no competing interest.

This study was funded by National Council for Scientific and Technological Development (CNPq) and Brazilian Society of Rheumatology

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Ethics committee of Hospital das Clinicas of Universidade Federal de Pernambuco and Brazilian National Committee of Ethics in Research (CONEP/CNS/MS) gave ethical approval for this work. Technical advice number: 3.955.206 CAAE number: 30186820.2.1001.8807 Confirm information using CAAE number: https://plataformabrasil.saude.gov.br/login.jsf;jsessionid=vijREetywDIn7gqLcXvlXAnf

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