Research Establishes Link Between Gum Disease and Rheumatoid Arthritis
New research has documented a strong link between gum disease (periodontitis) and rheumatoid arthritis (RA), indicating a 'vicious cycle' where each condition exacerbates the other and triggers inflammation. The study, led by the University of Birmingham in collaboration with the University of Michigan, aimed to understand this relationship.
Rheumatoid arthritis is an autoimmune disorder that impacts joints and other body parts, affecting approximately 1.5 million Americans and 23 million individuals globally. It is a significant cause of disability.
Key Findings on Bacterial Communities
An unhealthy community of bacteria located beneath the gumline can induce local gum inflammation and systemic body-wide inflammation, serving as a mechanistic connection between periodontitis and rheumatoid arthritis. The presence of these bacteria and their byproducts appears to worsen autoimmune responses in RA. Conversely, RA itself can make the oral environment more susceptible to dysbiosis, an imbalance in the microbial community, thereby perpetuating the cycle.
Researchers determined that patients with RA, even without active periodontitis, exhibited a virulent group of bacteria and increased inflammation under their gumline. This suggests that inflammation associated with RA can negatively affect oral health. The study supports a mutually reinforcing relationship between periodontitis and RA, highlighting the importance of integrated dental and rheumatological care for affected patients.
Study Design and Outcomes
The study involved approximately 150 volunteers, including individuals with RA, periodontitis, both conditions, and healthy controls. It included a randomized controlled trial where patients with both RA and periodontitis were assigned to one of two groups: receiving a deep cleaning or receiving instructions on oral hygiene. The deep cleaning involved treating pockets under the gumline to remove plaque, tartar, and unhealthy root surface tissue, followed by regular monitoring and cleanings. The control group received deep cleaning after a six-month observation period.
The group that received treatment for their gum disease demonstrated significantly greater improvement in their RA status compared to the group that initially received only cleaning instructions.
Implications for Treatment and Future Research
Maintaining a healthy oral bacterial community through frequent cleanings and monitoring for dysbiosis is crucial. Deep cleanings, typically performed under local anesthesia, involve removing plaque, tartar, and necrotic root surface tissue to create an environment conducive to healing. This process is often the initial step in treatment and may involve additional procedures or ongoing monitoring.
Findings indicated that the interlinking of RA and periodontitis is a community-level event (dysbiosis) rather than attributed to a single oral pathogen. The observed positive response to deep cleaning emphasizes the need to approach the body as an integrated system rather than treating each organ system separately. Controlling inflammation triggers, such as smoking, vaping, high body mass index, and poor oral hygiene, is important for overall health.
Researchers plan to conduct more randomized trials with larger populations and are exploring similar circular relationships in other related diseases, such as Scleroderma and Lupus.
Collaborating Authors
Co-authors included Iain Chapple, Thomas Dietrich, Melissa Grant, Paola de Pablo, and Praveen Sharma from the University of Birmingham; Isabel Lopez-Olivia from the University of Birmingham and Birmingham Dental Hospital; Karim Raza and Andrew Filer from NIHR Birmingham Biomedical Research Centre in Inflammation; Stefan Serban from the University of Leeds School of Dentistry; Akshay Paropkari from Clear Labs Inc.; and Shweta Saraswat from Ohio State University. Purnima Kumar, professor and chair of the Department of Periodontics and Oral Medicine at the U-M School of Dentistry, served as the senior and corresponding author.