A new study has found a link between gum disease and greater rates of cognitive decline in people with early stages of Alzheimer’s disease.
Periodontitis or gum disease is common in older people, according to researchers at King’s College London and the University of Southampton in England, who note it may become more common in Alzheimer’s disease because of a reduced ability to take care of oral hygiene as the disease progresses.
Higher levels of antibodies to periodontal bacteria are associated with an increase in levels of inflammatory molecules elsewhere in the body, which in turn has been linked to greater rates of cognitive decline in Alzheimer’s disease, the researchers said.
In the new study, published in PLOS ONE, 59 participants with mild to moderate Alzheimer’s disease were cognitively assessed and a blood sample was taken to measure inflammatory markers in their blood.
Dental health was assessed by a dental hygienist who was blind to cognitive outcomes.
The majority of the participants — 52 — were followed-up at six months when all assessments were repeated.
The presence of gum disease at baseline was associated with a six-fold increase in the rate of cognitive decline over the six months, according to the study’s findings.
Periodontitis at baseline was also associated with a relative increase in the pro-inflammatory state over the six-month follow-up period.
The researchers postulate that gum disease is associated with an increase in cognitive decline in Alzheimer’s disease, possibly via mechanisms linked to the body’s inflammatory response.
They suggest it may be worth exploring whether the treatment of gum disease might also benefit the treatment of dementia and Alzheimer’s disease.
“These are very interesting results which build on previous work we have done that shows that chronic inflammatory conditions have a detrimental effect on disease progression in people with Alzheimer’s disease,” said Professor Clive Holmes from the University of Southampton.
“Our study was small and lasted for six months, so further trials need to be carried out to develop these results. However, if there is a direct relationship between periodontitis and cognitive decline, as this current study suggests, then treatment of gum disease might be a possible treatment option for Alzheimer’s.”
Dr. Mark Ide, from the Dental Institute at King’s College London, notes that gum disease is widespread in the UK and the U.S.
In the UK in 2009, around 80 percent of adults over 55 had evidence of gum disease, while 60 percent of adults over the age of 75 had less than 21 of their original 32 teeth, with half of them reporting gum disease before they lost teeth, he recounted.
“A number of studies have shown that having few teeth, possibly as a consequence of earlier gum disease, is associated with a greater risk of developing dementia,” he said.
“We also believe, based on various research findings, that the presence of teeth with active gum disease results in higher body-wide levels of the sorts of inflammatory molecules, which have also been associated with an elevated risk of other outcomes, such as cognitive decline or cardiovascular disease. Research has suggested that effective gum treatment can reduce the levels of these molecules closer to that seen in a healthy state.
“Previous studies have also shown that patients with Alzheimer’s disease have poorer dental health than others of similar age and that the more severe the dementia, the worse the dental health, most likely reflecting greater difficulties with taking care of oneself as dementia becomes more severe,” he concluded.
Source: King’s College London