- Studies suggest that treating gum disease (with other stroke risk factors) could reduce your risk for stroke.
- Gum bacteria known as P. gingivalis has been identified in carotid arteries, and gum infection bacteria known as Streptococcus sp DNA has been found in brain blood vessels.
- Gum disease was linked to strokes caused by a hardening of large arteries in the brain and also with severe artery blockages.
Experts know there’s a link between gum disease and cardiovascular events, but now new research has put a spotlight on why this link exists.
According to two research abstracts being presented at the American Stroke Association’s International Stroke Conference, gum disease (also known as periodontitis or periodontal disease) was linked to a higher rate of strokes caused by the hardening of large arteries in the brain and also with severe artery blockages that haven’t yet caused symptoms.
The studies suggest that treating gum disease (with other stroke risk factors) could reduce your risk for stroke.
Gum disease is a chronic bacterial infection that impacts soft and hard structures supporting the teeth. It’s associated with inflammation, which seems to play a role in blood vessel hardening, also known as atherosclerosis.
The studies don’t show that gum disease can cause artery blockage or stroke, just that there’s a link.
Cardiovascular diseases, including strokes, are multi-factorial diseases.
Periodontal diseases could be one of the variables associated with cardiovascular diseases, but there are numerous other risk factors that make the cause-effect relationship effect difficult to determine, noted Paulo Camargo, DDS, FACD, a professor at the UCLA School of Dentistry.
While there could be sources of inflammation that impact blood vessels, researchers think the gums are the likely origin, noted Dr. Souvik Sen, a professor and chair of clinical neurology at the University of South Carolina School of Medicine in Columbia, who led both studies.
This is because the gum bacteria known as P. gingivalis has been identified in carotid arteries, and gum infection bacteria known as Streptococcus sp DNA has been found in brain blood vessels.
Here are the major findings from both studies:
Of 265 patients studied who experienced a stroke between 2015 and 2017, the team found that large artery strokes due to intracranial atherosclerosis were twice as common in patients with gum disease as in those without gum disease.
The people with gum disease were 3 times as likely to have a stroke involving blood vessels in the back of the brain, which controls vision, coordination, and other vital bodily functions.
Gum disease was more common in patients who had a stroke involving large blood vessels within the brain, yet not more common among those who had a stroke due to a blockage in blood vessels outside the skull.
Researchers examined two magnetic resonance images (MRIs) to evaluate 1,145 people who hadn’t experienced a stroke. They also conducted oral exams to classify the presence and severity of gum disease.
They discovered that arteries in the brain were severely blocked (50 percent or more) in 10 percent of those evaluated.
People with gingivitis, or inflammation of the gums, were twice as likely to have moderately severe narrowed brain arteries from plaque buildup compared to those with no gum disease.
After they adjusted for risk factors, those with gingivitis were 2.4 times as likely to have severely blocked brain arteries.
“It’s important for clinicians to recognize that gum disease is an important source of inflammation for their patients and to work with patients to address gum disease,” Sen said in a statement.
Thomas E. Van Dyke, DDS, PhD, a periodontitis researcher, vice president for clinical and translational research at the Forsyth Institute, and professor in oral medicine, infection, and immunity at Harvard School of Dental Medicine, said the research confirms what he and others have found.
Sen’s team was able to further correlate that gum disease patients had a higher proportion of stroke due to posterior circulation disease, a specific subtype of stroke.
They also found people with gum disease had a significantly higher rate of stroke due to intracranial atherosclerosis (ICAS) compared to those without gum disease. Showing this localization sets this study apart, Van Dyke said.
Research has indicated that local, chronic inflammation has a systemic impact on the body.
“Gums are a common space for chronic inflammation that people don’t do much about,” Van Dyke said. This is because gum disease doesn’t always hurt right away. Even if it does, many people ignore it.
“Chronic inflammation is not good for you,” he said. “[It] has an impact on whole-body health. It can have systemic implications.”
Gum disease treatment has been shown to improve control of high blood pressure, diabetes, and cholesterol, all of which are stroke risk factors, Sen said. He’s working on another trial to test what type of gum disease treatment can reduce the risk of stroke.
Having periodontal health is essential to maintain healthy teeth. “It might have the additional benefits of mitigating the risks for a cardiovascular event,” Camargo added.