Here’s Why Gum Disease Has Been Linked to Severe COVID-19, According to a Dentist

A new study found that coronavirus patients with gum disease were nine times more likely to die—but why?

• A new study suggests that people with gum disease could be nearly nine times more likely to die of COVID-19 than people without dental problems.
• Researchers found that those with periodontal disease were also 3.5 times more likely to be admitted to the ICU and 4.5 times more likely to require a ventilator.
  
• A dentist explains why gum disease could be linked to a more severe case of COVID-19.
  

From the beginning, doctors have known that COVID-19 is especially dangerous for high-risk groups, including older adults and people with underlying health conditions like heart disease and asthma. But research is still uncovering new risk factors, which now includes gum disease. The condition may affect up to half of American adults, and appears to be linked to a higher COVID-19 death rate, per a new study published earlier this month in the Journal of Clinical Periodontology.

In the study, researchers followed 568 patients infected with the novel coronavirus, dividing them into two groups: those without major issues (mild symptoms) and those who faced complications like ICU admission and ventilation or, eventually, death. They found that COVID-19 patients with gum disease were nine times more likely to die, 4.5 times more likely to require a ventilator, and 3.5 times more likely to be admitted to the ICU than patients without signs of dental issues.

It’s not the only science linking the coronavirus and gum health; research from Mexico and the United Kingdom, respectively released in June and November last year, also identified periodontal disease as a significant risk factor of severe SARS-CoV-2 infection and death. Newly discovered oral symptoms like “COVID tongue,” which causes bumps, inflammation, and discoloration on the tongue, further drive home the connection between the virus and the mouth.

“We’ve known for a long time, decades, that oral health is connected to lung and cardiovascular health,” says Kami Hoss, D.D.S., member of the Board of Counselors at the UCLA School of Dentistry and CEO of San Diego-based practice The Super Dentists. “In fact, what happens in your mouth really impacts the health of many parts of the body.”

What is gum disease?

Gum disease—called gingivitis in early stages and periodontitis in later, more serious ones—is caused by bacteria in the mouth that infect the tissue around the teeth, which results in inflammation. Those bacteria form the plaque that build up on our teeth; without proper care, the plaque hardens and spreads below the gums, speeding up the disease process.

Gums become inflamed at first, then start to pull away from the teeth as the disease progresses, Dr. Hoss explains. Eventually, teeth can become mobile, shifting around and even falling out. Symptoms include swollen gums, tooth sensitivity, bad breath, bleeding, and changes in bite.

Periodontal disease impacts just under half of American adults 30 and older, according to the Centers for Disease Control and Prevention (CDC). It also becomes more common with age; 70% of people 65 and older have some form of gum disease. Men and smokers are more likely to have some form of periodontal disease, but it can affect anyone. Gum disease is also more likely in people with systemic conditions like hypertension, diabetes, and respiratory diseases.

OK, so what is the connection between gum disease and COVID-19?

Even though you go to different types of doctors for your teeth and body, your teeth are part of your body—it’s all one system, Dr. Hoss explains. “People have really forgotten that your mouth is connected to your body, and what happens in your mouth impacts the body in all sorts of ways.”

The most recent study mentioned above discovered high levels of blood markers indicating inflammation in COVID-19 patients with gum disease, meaning that systemic inflammation could be the culprit behind the higher risk of complications.

Those same bacteria might also cause COVID-19 complications when patients inhale them into their lungs during their illness, Dr. Hoss says. The resulting secondary infections—on top of the one already making it difficult to breathe—could require assisted ventilation. Another theory is that ACE2 receptors, which act as a point of entry for SARS-CoV-2 and exist in large numbers in the mouth, could become overactive in those with gum disease, potentially offering reduced resistance to the virus.

Out of all of these theories, however, it’s most likely that inflammation is the driving factor of COVID-19 complications in people who have signs of gum disease, Dr. Hoss explains.

Can having gum disease directly lead to a severe COVID-19 infection?

For now, there is no concrete data on whether gum disease increases the likelihood of infection. “There was insufficient evidence to link periodontal disease with an increased risk of COVID-19 infection,” the researchers of the United Kingdom study concluded. “However, amongst the COVID-19 positive, there was significantly higher mortality for participants with periodontal disease.”

Although there’s a clear correlation between serious periodontal disease and a severe case of COVID-19, their true relationship is probably more complicated than simple cause and effect. The bacteria and inflammation already present with gum disease could aggravate a nascent SARS-CoV-2 infection, Dr. Hoss explains, or the gums might rather serve more as an indicator of overall health.

Gum disease is also more prevalent in patients with hypertension, cardiovascular disease, diabetes, asthma, pregnancy, and cancer, all known comorbidities of COVID-19. The exact relationship between these conditions and oral health remains unknown, per the Mexico study, but it certainly makes sense that COVID-19 would fit in with them.

Until more research is completed, however, there is no way to draw a clear association between the diseases—and no way to tell if treatment of periodontal disease can also lessen the risk of COVID-19 complications.

What should I do to prevent gum disease?

If your gums bleed when you brush and floss your teeth, that’s probably a sign of periodontal disease, Dr. Hoss explains. Swollen gums are also a common first symptom, and pain or soreness might present in some people, although painless gums are more common.

“It can go for months and years without getting diagnosed, and that’s why it’s so critical to see your dentist routinely,” Dr. Hoss says. “The best treatment is prevention.”

To keep your mouth in good shape, the CDC recommends brushing twice a day and flossing at least once every day, which can effectively remove the bacteria that cause gum disease. You should also see a dentist at least once a year (ideally every six months), since they’ll be able to clean plaque below the gums and monitor for serious issues.

Patients with gingivitis can keep it at bay with proper tooth and gum care, plus dentist intervention; patients with periodontitis might require more extensive dental work, medication, and corrective surgery to protect their gums. If you’re worried about your gums, visit your dentist, who will give you options to stop or reverse the condition.

“This study is an opportunity for us to remind people how absolutely critical their oral health is, both in normal times and especially during this pandemic,” says Dr. Hoss, who stresses the importance of visiting the dentist despite COVID-19. “Take care of your oral health—go to the dentist regularly and do a good job at home.”

This article by Jake Smith was originally posted on Prevention.com on February 18, 2021.