Comparison of lymphocyte populations, cytokine, and autoantibody profile in patients with rheumatoid arthritis: a study of cases with COVID-19 and controls without COVID-19

INTRODUCTION: The SARS-CoV-2 pandemic is associated with the development of acute respiratory distress syndrome (ARDS) and post-COVID syndrome (PCS). PSC has been linked to autoimmune diseases, including rheumatoid arthritis (RA), a condition characterized by chronic joint pain driven by dysregulated immune response. This study aims to evaluate the impact of SARS-CoV-2 infection on patients with RA. METHODS: A total of 300 RA patients were included in the study, categorized into two groups: patients with a history of SARS-CoV-2 infection (n = 148) and without prior COVID-19 infection (control group; n = 152). Demographic information, comorbidities, treatments, autoantibodies, cell populations, and cytokines were assessed. RESULTS: A majority of the patients included in this study were female. A high percentage of patients completed the COVID-19 vaccination schedule. The mean age at RA diagnosis was 44.71 years, with most patients presenting with low disease activity. Patients with a history of SARS-CoV-2 infection reported headache, cough, and fatigue more often. A proportion of these symptoms persisted beyond 12 weeks, consistent with PCS. Autoantibody analysis revealed a high seropositivity rate in both groups, with no statistically significant differences related to SARS-CoV-2 infection. Similarly, the evaluation of immune system cell populations showed no significant variations between groups. Cytokine level analysis also demonstrated no statistically significant differences between cases and controls. However, IL-6 data were unavailable for 37% of participants. CONCLUSIONS: Long-term follow-up did not demonstrate statistically significant alterations in the immunological profile of RA patients with SARS-CoV-2 infection. Nevertheless, further prospective studies are required to elucidate potential long-term immunological effects in this population.