Risk factor gums: Anyone who suffers from chronic inflammation of the gums could have a higher risk of a severe course of Covid-19. Patients with periodontitis have to be treated in the intensive care unit 3.5 times more often and 4.5 times more often ventilated, as a study of 560 patients suggests. The cause of this could be the inflammatory messengers generated by periodontitis, but also a direct effect of the oral bacteria.
Most people get infected with the SARS-CoV-2 coronavirus without any problems, but around 20 percent of Covid-19 patients suffer a severe course: They have to be treated in hospital, some of them have a severe, body-wide inflammatory reaction, the cytokine storm. Classic risk factors for such a severe course are cardiovascular diseases, diabetes, obesity, but genetic factors and the immune type also play a role.
Does oral health affect the course of Covid?
Now researchers have identified another risk factor: periodontal disease. This chronic inflammation of the gums is caused by bacteria and in extreme cases can lead to teeth falling out. Around half of all adults worldwide develop mild to moderate periodontitis, around ten percent suffer from a more severe form. It has long been known that the underlying inflammation and the messenger substances it generates can also promote other diseases, including cardiovascular diseases, Alzheimer’s and even cancer.
That is why Nadya Marouf from Hamad Medical Corporation in Doha and her colleagues took a closer look at the role of periodontitis in Covid-19. The starting point was that some of the messenger substances observed in severe courses are also released in gingivitis: “Covid-19 mortality is associated with increased serum levels of interleukin-6, the C-reactive protein, D-dimer and ferritin”, explain it.
For their study, the researchers examined the course of Covid-19 in 568 patients who were admitted to hospitals in Qatar between February and July 2020. With the help of electronic medical files, they were also able to understand whether and to what extent the affected person suffered from periodontitis.
More ventilation, higher mortality
The result: 33 of the 258 Covid 19 patients with periodontal disease developed severe complications and had to be treated and ventilated in intensive care. There were only seven of the 310 patients with no or only mild gingivitis. More detailed analyzes showed that the severe course also occurred disproportionately more often in periodontal disease patients when other risk factors were taken into account.
Overall, the risk was as follows: Covid-19 patients with periodontitis were 3.5 times more likely to be admitted to the intensive care unit, they needed a ventilator 4.5 times more often and died almost nine times more often than those without gum disease. Inflammation-related biomarkers were also increased in COVID-19 patients with periodontal disease. According to the researchers, this strongly suggests that periodontitis, like other previous illnesses, is a risk factor for severe courses of Covid-19.
Effect via messenger substances or the bacteria directly
Why and how the gingivitis affects the course of Covid-19 is still unclear. According to one hypothesis, the messenger substances released in the mouth favor systemic inflammation and the overreaction of the immune system during the cytokine storm. Another assumption would be that the periodontal bacteria affect the coronavirus or the ACE2 receptors on the cells.
Another possibility would be a secondary infection by periodontal bacteria, which get from the mouth into the lungs and cause additional inflammation there. “This can contribute to the deterioration of patients with Covid-19 and increase the risk of death,” explains co-author Mariano Sanz from the Complutense University of Madrid. He therefore recommends disinfecting the oral cavity of Covid 19 patients with periodontitis before ventilation.
Oral health matters right now
In general, doctors recommend not to neglect oral health, even in times of pandemic: “Establishing and maintaining periodontal health can become an important part of the care of Covid-19 patients. Oral care should be part of the health recommendations in order to reduce the risk of severe disease, “said Bettina Dannewitz, President of the German Society for Periodontology, commenting on the study results. (Journal of Clinical Periodontology, 2021; doi: 10.1111 / jcpe.13435)
Source: German Society for Periodontology eV