4. Immune Response
Rheumatoid arthritis is an autoimmune disorder in which the body mistakenly perceives its own healthy tissue as a dangerous invader. In an attempt at healing, your immune system attacks those tissues. It is a useful system if the tissue really is dangerous, but when it comes to RA, this is a case of mistaken identity.
With rheumatoid arthritis, the immune system doesn’t stop at the joints but also attacks the heart, eyes, bones, lungs, and skin. This erroneous immune response has been directly linked to skin cancer, but damaged cells in general are also vulnerable to other types of cancer.