Pre-rheumatoid arthritis

The typical evolution of rheumatoid arthritis (RA) is that a person, with genetic risk factors, develops autoantibodies and subclinical inflammation under relevant environmental influences. There are indications that the primary site of the pathology is at mucosal surfaces (e.g. in the gums, lungs, and/or the gut), after which the disease translocates to the joints. Preclinical RA can be defined at the phase during which no clinically apparent features are present (i.e. no symptoms of inflammatory arthritis or clinically apparent joint swelling) but during which RA related biologic derangements such as the presence of autoantibodies are present. This chapter presents an overview of the risk factors, stages, and events occurring during the pre-RA phase. A better understanding of the factors involved will enable more accurate prediction of RA at the individual level and selection of high-risk individuals for inclusion in preventive studies. Several pharmacologic and non-pharmacologic studies aiming to prevent or delay the onset of RA in at-risk individuals are currently underway. It is hoped that such interventions in the pre-RA and indeed in the preclinical-RA phases will allow us to reduce the risk of RA and prevent RA developing in at least a proportion of at-risk patients.