Precipitating and perpetuating factors of rheumatoid arthritis immunopathology: linking the triad of genetic predisposition, environmental risk factors and autoimmunity to disease pathogenesis.

Rheumatoid arthritis (RA) is considered to occur when genetic and environmental factors interact to trigger immunopathological changes and consequently an inflammatory arthritis. Over the last few decades, epidemiological and genetic studies have identified a large number of risk factors for RA development, the most prominent of which comprise cigarette smoking and the shared epitope alleles. These risks appear to differ substantially between anti-cyclic citrullinated peptide (ACPA)-positive and ACPA-negative disease. In this article, we will summarise the risk factors for RA development that have currently been identified, outlining the specific gene-environment and gene-gene interactions that may occur to precipitate and perpetuate autoimmunity and RA. We will also focus on how this knowledge of risk factors for RA may be implemented in the future to identify individuals at a high risk of disease development in whom preventative strategies may be undertaken.