New Onset Autoimmune Disease More Common after Covid-19

ABSTRACT

Background: Viral infections including SARS-CoV-2 may trigger autoimmune disease through T-cell-mediated autoimmune response through molecular mimicry-cross-reactive T-cell recognition or bystander T-cell activation. Autoantibodies have been detected in patients with COVID-19 and some human proteins have homologous regions with SARS-CoV-2 peptides that could function as autoantigens. While there are scattered reports of various autoimmune diseases diagnosed after COVID-19, the risk is not known. Method(s) TriNetX (a global federated health research network providing access to electronic medical records across 72 large healthcare organizations) was utilized to define a cohort of adults 18 years or older seen on or after January 1, 2020 with at least one follow-up visit after an index date. Exposure was defined as COVID-19 diagnosis by ICD10 code or positive laboratory test. Controls did not have COVID-19 (by the same criteria) and were propensity score-matched to patients who had COVID-19 by age and female sex. Index date was the date of COVID-19 diagnosis or first provider visit for any reason during the study period for controls. Outcomes (see table) were assessed starting one month after index date (to exclude prior undiagnosed autoimmune disease) until one year after. Patients with a specific outcome prior to the index date or within one month after the index date were excluded from the analysis for that outcome. Incidence by COVID-19 exposure status and risk ratios for each outcome were assessed. Result(s) 4,016,472 patients were included (2,008,236 in both groups). Overall, mean (SD) age was 49.2 (17.9) and 57.7% were female. Patients who had COVID-19 were more likely to be white (63 vs 56.9%;p< 0.001). Rheumatoid arthritis, psoriasis and type 1 diabetes mellitus had the highest incidence after COVID-19 (0.24, 0.22 and 0.19%, respectively). While the incidence of most of the autoimmune diseases assessed were low in both groups, the risk ratios for all but one condition (Grave's) showed statistically significant higher risk in patients after COVID-19 than in those without COVID-19 (see table). Risk ratios were highest for polyarteritis nodosa (4.43, 3.27-6.01), reactive arthritis (3.56, 2.05-6.2) and ANCA-associated vasculitis (3.36, 2.6-4.34). Conclusion(s) Autoimmune diseases were more likely to be diagnosed within the first year after COVID-19 than in age-, sex-matched controls. Future work will assess the validity of autoantibodies in predicting autoimmune disease after COVID-19. (Table Presented).