People with rheumatoid arthritis (RA) may be up to four times more likely to have gum disease than people without this autoimmune disease. What's more, gum disease is often more severe in people with RA, a new study suggests.

The findings, which appear in the Annals of Rheumatic Disease, add to a growing body of evidence linking oral health to systemic diseases including RA.

During RA, the body's immune system misfires against its own joints and tissues, causing inflammation, joint damage, and pain.

The new study compared the teeth and gums of 91 people with RA and 93 age-matched individuals without RA. None of the participants were smokers, and none of the people with RA were taking RA drugs known as disease-modifying anti-rheumatic drugs. Most participants were women and the average age was in the early 40s.

Close to 65% of people with RA had gum disease, compared with 28% of their RA-free counterparts. Gum disease was more severe in people with RA. People with RA also had deeper pockets between their gums and teeth (a sign of gum disease severity) than those without RA. 

People with RA and gum disease were also more likely to test positive for the presence of anti-citrullinated peptide antibodies (ACPA). Researchers suggest that these antibodies may generate and maintain inflammation in the mouth and elsewhere in the body. Levels of ACPA tended to be higher in people with RA and gum disease than in those with RA and no gum disease.
Oral Health and RA Are Linked

"The connection is there and it's becoming better established," says David Pisetsky, MD, PhD. He is the chief of rheumatology at Duke University Medical Center in Durham, N.C.

"If you have RA, go to the dentist regularly and don't smoke," he says. Smoking is known to worsen both RA and gum disease.

Gum disease is worse in people with RA, but we don't yet know what comes first, the gum disease or the RA, says Eric Matteson, MD, MPH. He is the head of rheumatology at Mayo Clinic in Rochester, Minn. 

"If you have RA and bad teeth, paying attention to your oral hygiene could be very important," he says. "Chronic inflammation in your mouth can be an aggravating factor for chronic inflammation elsewhere, and this is not widely appreciated by patients or doctors."

In this sense, "the new study should serve as a springboard to heightened awareness of this problem."

Saul Pressner, DMD, says he would like to see people with RA come in up to four times a year for cleaning. He is a dentist in private practice in New York City.