According to a large study, catching COVID-19 could increase the risk of developing autoimmune diseases by 43% in the months following the infection. Previous studies had linked COVID-19 to an increased risk of autoimmune diseases but were limited to small studies that focused on specific conditions such as such as autoimmune haemolytic anaemia, which affects red blood cells, and Guillain-Barre syndrome, which affects nerve cells. (Also read: Long Covid more than doubles risk of heart complications: Study)
In this yet to be peer reviewed study posted in the preprint database medRxiv, researchers analysed the health records of 640,000 people in Germany who caught COVID-19 in 2020 and 1.5 million people who did not catch the coronavirus to explore how the infection could affect the risk of developing any of 30 autoimmune conditions. They found that more than 15% of people who had caught COVID-19 developed an autoimmune disease for the first time during the follow-up period, compared with roughly 11% of the people who had not caught COVID-19. Vasculitis, thyroid problems, psoriasis, and rheumatoid arthritis were strongly linked to prior COVID-19 infection.
As per Dr Ravi Shekhar Jha, Covid can open autoimmune genes or lead to relapse of autoimmune disease that had already gone into remission for many years in some people but need not lead to an autoimmune disease directly.
“Covid cannot lead to any autoimmune disease directly, however, like many other viral illnesses, Covid can certainly harm in two ways as far as autoimmune disease is concerned. It can unmask an autoimmune disease in someone who has a family history of autoimmune disease. It can lead to opening up of autoimmune genes. For those who are already a known case of autoimmune disease, and were in remission for many years, Covid can lead to relapse of or waking up of sleeping autoimmune genes,” says Dr Ravi Shekhar Jha, Director and Unit Head Pulmonology, Fortis Escorts Hospital Faridabad.