Today in JAMA Network Open, South Korean researchers identify a significantly higher risk of multiple new-onset autoimmune and autoinflammatory connective-tissue disorders after COVID-19 infection, some associated with illness severity, but vaccination lowers the risk.
For the retrospective study, researchers analyzed nationwide data from the Korea Disease Control and Prevention Agency COVID-19 National Health Insurance Service on COVID-19 patients from October 2020 to December 2021. A control group was made up of uninfected people identified through the National Health Insurance Service of Korea.
The average age of the 354,527 COVID-19 patients was 52.2 years, and 50.5% were women. Among the 6,134,940 controls, the average age was 52.1 years, and 50.1% were women. The average follow-up time for the COVID-19 and control groups were 120 and 121 days, respectively.
"Possible associations of COVID-19 with autoimmune diseases… have been suggested, because SARS-CoV-2 appears to perturb self-tolerance and trigger autoimmune reactions via cross-reactivity that may lead to the development of autoimmune diseases," the study authors wrote.
Vaccinated participants at lower risk
Relative to controls, COVID-19 patients had significantly higher risks of alopecia areata (adjusted hazard ratio [aHR], 1.12), alopecia totalis (aHR, 1.74), antineutrophil cytoplasmic antibody–associated vasculitis (aHR, 2.76), Crohn disease (aHR, 1.68), and sarcoidosis (aHR, 1.59).
These findings suggest that autoimmune and autoinflammatory connective tissue disorders may manifest as post–COVID-19 sequelae, highlighting the potential long-term health ramifications associated with COVID-19.
The risks of alopecia totalis, psoriasis, vitiligo, vasculitis, Crohn disease, ulcerative colitis, rheumatoid arthritis, adult-onset Still disease, Sjogren syndrome, ankylosing spondylitis, and sarcoidosis were associated with increasing COVID-19 severity.
In subgroup analyses, unvaccinated participants were at greater risk of autoimmune diseases such as alopecia areata, alopecia totalis, and Crohn disease, as well as for COVID-associated cardiovascular control outcomes. But in vaccinated participants, the increased risks were lower for both autoimmune and cardiovascular control outcomes. The risk of psoriasis was slightly higher in a COVID-19 subgroup made up of men and those who had severe COVID-19.
"These findings suggest that autoimmune and autoinflammatory connective tissue disorders may manifest as post–COVID-19 sequelae, highlighting the potential long-term health ramifications associated with COVID-19," the researchers wrote.