Can those who have fallen ill with Covid develop a rheumatological disease?

I read that there may be a link between Covid and an increased risk of developing rheumatological diseases: is this true? What is this association based on?

He replies Carlo Selmihead of Rheumatology and Clinical Immunology, Humanitas Institute, Milan (GO TO THE FORUM)

It has been hypothesized since the early stages of the Sars-CoV-2 pandemic a direct link between Covid and chronic inflammatory and autoimmune diseases. This came after the identification of common mechanisms between Covid and rheumatoid arthritis the so-called cytokine release syndrome (also known as cytokine storm), which is observed as a consequence of both Covid and some rheumatological diseases. There are at least three observations that have strengthened this hypothesis.

Drugs used in rheumatology

First, many cases have been described of people who developed chronic inflammatory or autoimmune diseases, such as arthritis or vasculitis, after contracting the viral infection. Secondly, the immunological mechanisms associated with the severity of Covid are also important in rheumatological diseases, as in the case of interleukin 6 (IL-6) in rheumatoid arthritis. Third: Covid was successfully treated using drugs that have been in use for a long time also in rheumatology, such as tocilizumab or glucocorticoids.

The study conducted in Hong Kong

Based on these connections it was hypothesized that having had Covid could increase the risk of developing a rheumatological disease and that vaccination against Sars-CoV-2 could reduce it. A study, conducted in Hong Kong between April 2020 and November 2022compared the risk of developing autoimmune diseases (including many rheumatological diseases) in over one million people who had Covid and three million people who did not contract the infection.

The vaccine reduces the risk

The comparison of these two large populations has shown that those who had had Covid showed a significantly higher risk of developing spondyloarthritis (+32%), rheumatoid arthritis (+29%), vasculitis (+46%), compared to people who had not had the infection. Completing two doses of the Sars-CoV-2 vaccine instead reduced the risk of developing other rheumatological diseases, such as anti-phospholipid antibody syndrome and systemic lupus erythematosus.

The role of inflammation

Mechanisms that could explain this increased risk of rheumatological diseases include the role of inflammation observed during Covid as a trigger of autoimmunity, a mechanism common to many rheumatological diseases.