Background/Purpose: Autoimmune inflammatory rheumatic diseases (AIRD) such as rheumatoid arthritis and systemic lupus erythematosus affect 3-5% of Americans and causes significant morbidity due to chronic inflammation and immune dysfunction¹. Patients with AIRD are vulnerable to infections due to their immune abnormalities and immunosuppressive therapies, including Disease modifying anti-rheumatic drug (DMARD) therapy². Understanding the impact of these treatments on COVID-19 outcomes is crucial. With COVID-19 vaccination, there’s an opportunity to protect this high-risk group^3,4. However, there’s inadequate data on vaccination rates, efficacy, and adverse events among patients’ with AIRD. This study compares the incidence of COVID-19 between patients on biological and conventional DMARDs.

Methods: A retrospective cross-sectional study was conducted from March 1st, 2020 to April 30th, 2022. Adult patients on immunosuppressive therapy (prednisone >=5mg, conventional and biologic DMARDs) at a rheumatology clinic were included. Statistical analysis used Chi-square tests for categorical variables and t-tests for continuous variables, with significance set at p < 0.05. Confidence intervals (95%) were calculated to assess estimate precision.

Results: The study included 790 patients, predominantly female (81.8%), with a racial composition of 39.4% Caucasian, 48.0% African American, and 12.5% Other. The most common diagnoses were rheumatoid arthritis (40.9%), Systemic Lupus Erythematosus (16.5%), and Psoriatic Arthritis (9.4%). COVID-19 incidence was 16.3%, with no significant differences across gender (12.5% in males vs. 17.2% in females, p = 0.169, 95% CI: -0.870 to 4.177) or ethnicity (16.1% in Caucasians, 15.3% in African Americans, and 21.2% in Others, p = 0.362). Treatment regimens included hydroxychloroquine (31.3%), methotrexate (18.4%), adalimumab (11.0%), and etanercept (6.7%), with 23.3% receiving biologics and 76.7% DMARDs. No significant difference in COVID-19 infection rates was observed between biologics (18.5%) and DMARDs (15.7%, p = 0.368, 95% CI: -0.806 to 4.113). Higher infection rates were noted for guselkumab (66.7%) and apremilast, methotrexate (50%). Mortality was low with seven deaths, but a higher death rate was associated with abatacept (7.1%) and mycophenolate (6.5%). Despite high vaccination rates, vaccinated patients showed a higher incidence of COVID-19, likely due to underlying factors.

Conclusion: This study suggests that conventional and biological DMARD use does not increase the risk of SARS-CoV-2 infection or COVID-19-related mortality in patients with AIRD, irrespective of vaccination status. Despite high vaccination rates, vaccinated individuals had a higher incidence of COVID-19, likely due to other factors. Specific immunotherapies such as abatacept (7.1%) and mycophenolate (6.5%) were associated with higher mortality rates, emphasizing the need for careful monitoring. The findings support the safe use of DMARD therapy in managing AIRD during the COVID-19 pandemic.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/comparison-of-covid-19-infection-and-mortality-rates-in-vaccinated-and-unvaccinated-patients-with-autoimmune-inflammatory-rheumatic-disease-aird-using-conventional-and-biologic-dmard-therapy-at-an-u/