From Mouth to Back: Gum Disease and AS

Ankylosing spondylitis linked to prior periodontitis diagnosis

(RxWiki News) Many diseases are driven by inflammation, or the swelling of tissues and organs. Inflammation plays a part in both arthritis and gum disease. As such, there may be a link between arthritis and gum disease.

A recent study revealed that patients with ankylosing spondylitis (a type of spinal arthritis) were more likely to have had periodontitis (a type of gum disease) in the past compared to patients without ankylosing spondylitis.

The authors noted that treating periodontitis "did not greatly affect the association between the two conditions," which may suggest that inflammation isn't the only reason for the link between ankylosing spondylitis and periodontitis. However, the exact reason for the link remains unclear.

"Take special care of your teeth."

For their research, Joseph J. Keller, MD, MPH, of Taipei Medical University in Taiwan, and colleagues set out study the possible link between ankylosing spondylitis and chronic periodontitis.

In background information to the study, the authors said, "Ankylosing spondylitis is one type of chronic inflammatory rheumatic disease. It has been suggested that rheumatic diseases may have additional underlying factors in common with periodontitis. However, few studies have addressed the possible link between ankylosing spondylitis and chronic periodontitis."

The study included 6,821 patients with ankylosing spondylitis and 34,105 without ankylosing spondylitis.

Results showed:

  • The rate of prior periodontitis was 41.5 percent among ankylosing spondylitis patients versus 25.9 percent among those without ankylosing spondylitis.
  • Ankylosing spondylitis patients were more likely than those without ankylosing spondylitis to have been previously diagnosed with chronic periodontitis, with an odds ratio of 1.84.
  • Ankylosing spondylitis patients were 1.70 times more likely than those without ankylosing spondylitis to have undergone one of two procedures to treat periodontitis.

An odds ratio explains the odds of an event happening in one group versus the odds of that event in another group. In this case, for example, ankylosing spondylitis patients had 1.84 times the odds of prior periodontitis than those without ankylosing spondylitis.

According to the authors, "This study revealed an association between ankylosing spondylitis and a prior diagnosis of chronic periodontitis," and thus the findings contribute to similar findings from smaller past studies that looked at patients with all sorts of rheumatic diseases.

Still, the study had its limitations, which included:

  • less accurate diagnoses
  • the inability to adjust for other factors that could increase risk of periodontitis, including family history of cancer, cigarette smoking and occupational exposures
  • the potential for selection bias, meaning ankylosing spondylitis patients may have been more likely to have a prior periodontitis diagnosis not because of a link between the conditions but because they were already more exposed to the medical community
  • difficulty determining ankylosing spondylitis diagnoses, as patients can go many years before receiving a definitive diagnosis
  • the inability to calculate the risk of ankylosing spondylitis among patients with chronic periodontitis

In light of their findings, the authors concluded, "Clinicians treating patients with ankylosing spondylitis are advised to refer them to specialists to evaluate their periodontal health."

The study was published December 27 in Arthritis & Rheumatism. No funding or disclosure information was available.

Review Date: 
January 9, 2013