September 25, 2020
In this time of social distancing and coronavirus concerns, here’s an important reminder to keep your dental health in check and visit the dentist if you can. A large new study found that gum disease is tied to an increased risk of Alzheimer’s disease and other forms of dementia. Severe gum disease, with loss of teeth, was also tied to an increased risk of mild cognitive impairment, a brain disorder that often progresses to full-blown Alzheimer’s.
“We looked at people’s dental health over a 20-year period and found that people with the most severe gum disease at the start of our study had about twice the risk for mild cognitive impairment or dementia by the end,” said study author Ryan T. Demmer, of the University of Minnesota School of Public Health in Minneapolis. “However, the good news was that people with minimal tooth loss and mild gum disease were no more likely to develop thinking problems or dementia than people with no dental problems.” The findings appeared in the journal Neurology.
For the study, researchers looked at 8,275 men and women whose average age was 63. None had memory problems or dementia when the study began. All received a full periodontal exam, looking for signs of gingivitis and gum disease like gum bleeding, “pockets” around the teeth caused by a receding gumline, or lost teeth.
At the start of the study, 22% had no gum disease, 12% had mild gum disease, 12% had severe gum inflammation, 8% had some tooth loss, 12% had disease in their molars, 11% had severe tooth loss, 6% had severe gum disease, and 20% had no teeth at all.
By the end of the study, nearly 20 years later, nearly one in five participants, or 19%, had developed dementia. The researchers found that of the people who had healthy gums and all their teeth at the start of the study, 14% had developed dementia by the study’s end. But among those with severe gum disease, 22% had developed dementia. Those who had lost all their teeth had twice the risk of mild cognitive impairment or dementia compared to those with healthy gums and all their teeth.
Other studies have found that people who die with Alzheimer’s disease are more likely to have bacteria linked to gum disease in the brain than those who don’t have Alzheimer’s disease. It is possible that bacteria in the mouth could travel to the brain, causing damage there. Gum disease is also tied to body-wide inflammation, which may damage blood vessels throughout the body, including in the brain.
“Our study does not prove that an unhealthy mouth causes dementia,” since the data is observational and only shows an association, Dr. Demmer, the study’s lead author, said. But this study was large, and other research has likewise linked gum disease with an increased risk of dementia.
“The take-home message from this paper is that it further supports the possibility that oral infections could be a risk factor for dementia,” Dr. Demmer said. “Good dental hygiene” — including daily brushing and flossing as well as regular dental checkups — “is a proven way to keep healthy teeth and gums throughout your lifetime.” And good dental hygiene is good not just for dental health, these findings suggest, it may also be good for your brain.
By ALZinfo.org, The Alzheimer’s Information Site. Reviewed by Marc Flajolet, Ph.D., Fisher Center for Alzheimer’s Research Foundation at The Rockefeller University.
Source: Ryan T. Demmer, Faye L. Norby, Kamakshi Lakshminarayan, et al: “Periodontal Disease and Incident Dementia: The Atherosclerosis Risk in Communities Study (ARIC). Neurology, July 29, 2020