Today I stumbled across some research that I just knew was going to be interpreted wrongly in the popular press. Sure enough, when I Googled the subject, I found a number of articles that inverted the findings of the study in such a way as to suggest that periodontal disease caused or was a risk factor for rheumatoid arthritis.
The actual study actually said the opposite, that there was a strong risk-factor association between having rheumatoid arthritis (RA) and developing gum disease. This is important information for dentists, who now know to ask their patients whether they suffer from RA on the information sheets they fill out before their first visits. If so, then it becomes wise for the dentists to be on the lookout for early signs of periodontal disease, so that they can stop it before it becomes more advanced. Because over 1.3 million Americans suffer from RA, this is a significant finding that could help both their doctors and their dentists to keep their gums more healthy.
The actual research
The German researchers published their findings in the journal Annals of the Rheumatic Diseases. In the study, they examined 91 adults with RA, compared to a control group of 93 healthy adults. None of the subjects were smokers (a known risk factor for both rheumatoid arthritis and gum disease), and none had been treated with a type of arthritis medication called disease-modifying drugs, which could have skewed the results. The patients were examined by physicians, and interviewed about the condition of their gums. They were also tested for indications of inflammation, which is a known causative factor for periodontitis.
In technical terms, the researchers found that the pathogenesis of “oral bacterial infections and inflammation seem to be linked directly to the etiopathogenesis of rheumatoid arthritis.” Translated into plain English, this means that two-thirds of the subjects with RA also showed signs of gum disease, as opposed to only 28 percent of the healthy control group.
A paper presented at a meeting of the American College of Rheumatology reported similar findings, based on a study of 57 RA patients and 52 healthy control subjects published in the Journal of Periodontology. The Internet health information site WebMD reported on these findings by drawing some useful conclusions: “People with rheumatoid arthritis (RA) are eight times more likely to have gum disease than people without this autoimmune disease. Inflammation may be the common denominator between the two. … Making matters worse: people with RA can have trouble brushing and flossing because of damage to finger joints.” WebMD thus recommended that RA patients, who often suffer from joint pain because of their disease, might need special tools to help them with brushing and flossing, such as a Waterpik.
Conclusions and directions for future research
Other researchers have commented on these studies, pointing out that the conclusions are far from clear-cut. One the one hand, because RA often affects people’s dexterity, they may be simply less able to care for their teeth properly, and thus more prone to gum disease. On the other hand, both rheumatoid arthritis and periodontitis are systemic inflammatory disorders, and thus there may be other associations between the two conditions. Probing deeper into these associations may in the future reveal information that can help to cure both diseases.
For now, however, one thing is clear from the data. Although no one can say for sure that having gum disease puts you at increased risk of contracting RA, having RA definitely puts you at increased risk of contracting gum disease. So if you or someone you love has RA, encourage them to brush and floss diligently, and to see their dentists on a regular basis. Rheumatoid arthritis is enough of a burden to live with in itself; you don’t need to compound it by developing gum disease as well.