A UK study has suggested that gum disease could be linked to cognitive decline in people living with dementia. Although the results are not conclusive, the researchers believe that their study indicates that further research may help to validate their results.
Dementia could be made worse by Gum Disease
The University of Southampton and Kings College London were two of the institutions involved in the study which was published in the open-access, peer reviewed PLOS ONE which can be accessed online.
The aims of this cohort study were to find out whether periodontitis or gum disease could be linked to an increase in the severity of cognitive decline and dementia in people who were living with Alzheimer’s disease. The study recruited 60 people with an average age of 77.7 who had been diagnosed with mild to moderate dementia but were not living in nursing homes. The researchers chose participants who had at least 10 of their own teeth, who had not been treated for gum disease in the six months previous to the study and who were able to consent to take part in the research.
The researchers tested the participants’ mental function using accepted tools. The main measure was the Alzheimer’s Disease Assessment Scale (ADAS-cog) and the standardised Mini-Mental State examination (sMMSE). Blood samples were taken to test for antibodies which are found as the body’s reaction to periodontitis. The participants’ dental health was also measured by recording the number of teeth, measuring the spread of gum disease, giving each person a plaque score, recording gum bleeding sites and checking for any gaps between the gum and the root of the tooth and measuring their depth.
The main caregivers of the participants were also interviewed to help record the medical and dental history of the participants. All of the assessments were repeated at the end of six months.The researchers performed statistical analyses to examine whether people who had gum disease showed a different pattern of cognitive decline. Confounding factors were taken into account, including the age, gender and cognitive status of the person taking part. The group was evenly split into men and women.
As the study began, 22 of the 60 participants had some gum disease. There seemed to be no relationship between the severity of the cognitive impairment of a person and the presence of gum disease. When the people taking part were assessed again six months later, only 52 of the original 60 could be assessed. 15 of the original 22 people who had gum disease continued to have the condition and of the people who did not have gum disease originally, two more had developed it.
The ADAS-cog score of people who had already had gum disease averaged about a six point worsening score after 6 months but those who did not have periodontitis only averaged a one point worsening score. The adjustments for confounding factors made no difference to these results. The results of the other cognitive score, sMMSE showed similar results initially, but made no statistical difference after being adjusted.
The researchers suggested that their results showed that gum disease was linked with an increase in cognitive decline which was independent to the baseline cognitive state. Their small study was not able to prove cause and effect and the results may not be replicated in a larger study. The participants had all already been diagnosed with dementia, so the researchers were not asserting that gum disease could cause dementia, just that it could worsen the symptoms. Whether other general poorer health in people with dementia could also be contributing to the problems was not able to be examined. People who had cognitive decline can neglect to take care of themselves.
The study helps to add to the growing interest in whether dental health has a wider impact on the health of the body, but a larger study sample will be needed to help explore the possibilities of the effect that gum health could have on cognitive health.
Ide M., Harris M., Stevens A., et al., Periodontitis and Cognitive Decline in Alzheimer’s Disease, PLOS One, published online March 10, 2016