Cigarettes Cause More Severe Arthritis
March 15, 2002 -- Here's one more reason to quit smoking: it may save your joints. A new study shows cigarette smoking can cause a genetic reaction that leads to a more severe form of rheumatoid arthritis.
Rheumatoid arthritis (RA) is an often-debilitating condition in which the joints become painful, stiff, and swollen. Prior studies have shown that smokers seem to suffer from a more serious form of the disease, but it wasn't clear why.
Researchers now say this study, published in the March issue of Arthritis and Rheumatism, suggests that smoking may trigger a genetic chain of events that leads to more severe RA.
The gene GSTM1 is involved with the processing of an enzyme that detoxifies the cancer-causing agents found in tobacco smoke. About 50% of Caucasians don't have this gene. Prior studies have suggested that people lacking the GSTM1 gene have a more severe form of RA along with an increased risk of smoking-related cancers and heart disease.
Smoking has also been linked to an increase in the production of rheumatoid factor (RF), the substance checked for in blood tests to help determine if someone has RA.
Based on those findings, researchers speculated that smoking in people who already lack this gene might play a role in the development of more severe RA. They examined a group of 164 women with RA, including smokers and nonsmokers.
The researchers found past and current smokers had more joint damage and more severe symptoms than non-smokers. Smokers who lacked the GSTM1 gene also had significantly worse disease and higher levels of RF than those who lacked the gene but never smoked.
Since the gene is needed to detoxify the effects of smoking, researchers say smoking in people without this gene may have a big influence on the progression of the disease by affecting production of RF.