Urbanization
Studies show that early stages of life can affect the outcome of rheumatoid arthritis. Children who live in urban areas are much more likely to develop rheumatoid arthritis than children who live in rural areas, as rheumatoid arthritis has less incidence in these areas.
Early environment
Research shows that early development and the environment around the child have a high impact on developing or protecting against autoimmune diseases. This research inferred that children who live in a clean environment with fewer infections are more likely to develop an allergy and autoimmune diseases such as type 1 diabetes in early stages of life or autoimmune diseases in older ages such as rheumatoid arthritis.