Environmental Factors Contributing to the Development of RA

Abstract

Environmental factors play a major role in the pathogenesis of rheumatoid arthritis（RA）, accounting for approximately 70% of the disease, and the breakdown of immune tolerance caused by environmental factors is a trigger for the development of RA. The most important environmental factor is smoking. Other factors such as periodontal disease, microbiome, air pollutants, diet, and sex hormones have been implicated in the pathogenesis of RA, and their pathogenesis is gradually being elucidated. Cessation of smoking has been shown to have the potential for risk reduction, although the effects are stronger with quantity and duration. The effects of passive smoking during childhood have also been suggested. It has been suggested that periodontal disease may play a role in the pathogenesis of RA, not only for specific species of bacteria, but also by itself. Air pollutants such as PM2.5 and silica have been reported to cause various health problems, and RA, an autoimmune disease, is no exception. Knowledge of these environmental factors may lead to preventive intervention for people at high risk of RA. “Preventive intervention” in addition to “early diagnosis and early treatment” is essential to truly overcome the disease of RA, and further accumulation of knowledge is expected.