New data presented at EULAR 2007, the Annual European Congress of Rheumatology in Barcelona, Spain, sheds light on the role of environmental and genetic risk factors in the development of rheumatoid arthritis (RA).
Two new studies by a team in Sweden have identified smoking, a low formal level of education and certain metabolic indicators as important risk factors in the development of RA. These findings represent a significant step towards better understanding of the risk factors for RA and may contribute to improved future prevention and treatment of this debilitating disease.
The first study showed that smoking (odds ratio 1.77; 95% confidence interval 1.13 to 2.78) and a low level of formal education, such as elementary school education only versus university degree status (odds ratio 2.46 confidence interval 1.20 to 5.02), may independently increase the risk of developing RA.
The second study similarly highlights the link between of smoking and RA but, contrary to previously noted relationships between RA with active inflammation and impaired glucose tolerance, observes better glucose tolerance as a predictor of RA. In the multivariate model, a lower glucose level at 120 minutes after an oral glucose tolerance test (odds ratio 1.19 per mmol/L; confidence interval 1.04 to 1.35) and smoking (odds ratio 1.64; confidence interval 1.08 to 2.48) were both found to be independent predictors of RA. Thus the authors suggest that factors such as diet and genetics influencing metabolism may play an important part in RA development.