For decades it has been common knowledge that there is a connection between rheumatoid factor–positive and antibodies against citrullinated peptide–positive rheumatoid arthritis (RA) and smoking1. Cigarette smoking is regarded as one of the major environmental factors suggested to play a critical role in the development of a variety of disorders including autoimmune diseases such as RA, systemic lupus erythematosus, systemic sclerosis, multiple sclerosis, and Crohn’s disease2. It is safe to say that there is a widespread appreciation of the odiousness of smoking. However, does smoking also have an effect on actual disease activity and on the prognosis of patient outcome? Some statistical procedures, as well as some people, may nourish the illusion that there really is such a thing as a one-and-only risk factor. However, is this the case in reality? Is life really that simple?
Many aspects should be considered in relation to smoking and its consequences for patients with RA. Cigarette smoke represents a mixture of more than 4000 toxic substances including nicotine, polycyclic aromatic hydrocarbons, organic compounds, solvents, gas substances (primarily carbon monoxide), and free radicals. Extensive data suggest that smoking has a modulator role in the immune system contributing to a shift from Th type 1 to Th type 2 immune response3. Although there is consensus that smoking is highly likely to play a role in the pathogenesis of RA, does it also influence disease activity? The respective data …
Address correspondence to Dr. B.F. Leeb, 2nd Dept. of Medicine, Center for Rheumatology, Lower Austria, Landstrasse 18, Karl Landsteiner Institute for Clinical Rheumatology, Stockerau, A-2000, Austria. E-mail: burkhard.leeb{at}stockerau.lknoe.at