Having Covid-19 increases a person’s risk of developing an autoimmune disease in the year after infection, a large study out of South Korea and Japan reports, but vaccination helps decrease that risk.
Researchers used the medical records of 10 million Korean and 12 million Japanese adults to see whether those who had Covid were more likely to be diagnosed with autoimmune inflammatory rheumatic diseases, or AIRDs, in the year following infection. AIRDs include rheumatoid arthritis, systemic lupus erythematosus, Sjögren syndrome, mixed connective tissue disease, vasculitis, and other conditions. The Covid group was compared with an uninfected control group and a group of patients who had influenza during the same period from 2020 to 2022.