In the treatment of severe liver disorders such as cirrhosis the standard of care traditionally has not focused on the patient’s teeth. Yet now, investigators at the Virginia Commonwealth University (VCU) have just released new study findings that show routine oral care to treat gum disease (periodontitis) may play a role in reducing inflammation and toxins in the blood (endotoxemia) and improving cognitive function in people with liver cirrhosis. Results from the new study were published online in the American Journal of Physiology-Gastrointestinal and Liver Physiology through an article titled “Periodontal Therapy Favorably Modulates the Oral-Gut-Hepatic Axis in Cirrhosis.”
“Cirrhosis is associated with a systemic pro-inflammatory milieu, endotoxemia, and gut dysbiosis. The oral cavity could be an additional source of inflammation,” the authors wrote. “We aimed to determine the effect of periodontal therapy in cirrhosis through evaluating endotoxemia, inflammation, cognition, and quality of life (QOL).”
Cirrhosis is a growing epidemic in the U.S. and is hallmarked by the presence of scar tissue on the liver. When severe, it can often lead to liver failure. Complications of cirrhosis can include infections throughout the body and hepatic encephalopathy, a buildup of toxins in the brain caused by the advanced liver disease. Symptoms of hepatic encephalopathy include confusion, mood changes, and impaired cognitive function.
Previous research uncovered that people with cirrhosis have changes in the gut and salivary microbiota, which can lead to gum disease and a higher risk of cirrhosis-related complications. Also, studies have found that people with cirrhosis have increased levels of inflammation throughout the body, which is associated with hepatic encephalopathy.
In the current study, the VCU researchers studied two groups of volunteers that had cirrhosis and mild-to-moderate periodontitis. One group received periodontal care ("treated"), including teeth cleaning and removal of bacterial toxins from the teeth and gums. The other group was not treated for gum disease ("untreated"). The research team collected blood, saliva, and stool samples before and 30 days after treatment. Each volunteer took standardized tests to measure cognitive function before and after treatment.
“Age-matched cirrhotic/non-cirrhotic subjects exhibiting chronic gingivitis and mild/moderate periodontitis underwent periodontal therapy with follow-up at 30 days,” the authors wrote. “Saliva/stool for microbial composition and serum for MELD score, endotoxin and lipopolysaccharide binding protein (LBP) and immune-inflammatory markers (IL-1β, IL-6, histatins 1, 3, 5 and lysozyme) were collected at baseline and day 30. The cognitive function and QOL were also evaluated similarly.”
The treated group, especially those with hepatic encephalopathy, had increased levels of beneficial gut bacteria that could reduce inflammation, as well as lower levels of endotoxin-producing bacteria in the saliva when compared to the untreated group. The untreated group, on the other hand, demonstrated an increase in endotoxin levels in the blood over the same time period. The improvement in the treated group "could be related to a reduction in oral inflammation leading to lower systemic inflammation, or due to [less harmful bacteria] being swallowed and affecting the gut microbiota," the research team wrote.
Cognitive function also improved in the treated group, suggesting that the reduced inflammation levels in the body may minimize some of the symptoms of hepatic encephalopathy in people who are already receiving standard-of-care therapies for the condition. This finding is relevant because there are no further therapies approved by the FDA to alleviate cognition problems in this population, the researchers said. "The oral cavity could represent a treatment target to reduce inflammation and endotoxemia in patients with cirrhosis to improve clinical outcomes."