Diabetes and tooth loss can cause double trouble for the aging brain

Written by Cara Murez

Health Day reporter

WEDNESDAY, March 15, 2023 (HealthDay News) — Diabetes is a known risk factor for mental decline and dementia. Combined with complete tooth loss, the potential damage to the brain is even more significant, according to new research.

The findings highlight the importance of good dental care and diabetes control in aging adults, said Bei Wu, lead author of a new study of nearly 10,000 adults.

“Access to dental care for older adults, especially those with diabetes, is very important,” said Wu, associate research associate at New York University’s Rory Meyers College of Nursing and co-director of the NYU Aging Incubator in New York.

The American Diabetes Association recommends regular dental checkups for all people with diabetes — “but how many people follow through and how many clinicians recommend it?” Wu said.

Poor oral hygiene itself, particularly gum disease and tooth loss, has also been linked to cognitive impairment and dementia.

Wu notes that researchers are just beginning to understand how oral hygiene, diabetes and cognitive decline can worsen each other.

“We need to draw attention to this,” he said.

Inflammation plays a role in both diabetes and gum disease, the study finds. These inflammatory processes can contribute to a decline in reasoning and thinking skills – known as cognitive decline.

Poor nutrition is another way. Painful gums and missing teeth can make it difficult to chew healthy foods. This can lead to nutrient deficiencies. According to the study, the reduced blood sugar and insulin sensitivity seen in diabetes can also worsen nutritional deficiencies.

And certain bacteria associated with chronic periodontitis or gum disease can also affect cognitive function, Wu said.

To study this combined, researchers divided older adults into age groups: 65-74, 75-84, and 85 and older.

The researchers used data from the University of Michigan Health and Retirement Study from 2006 to 2018, which measured memory and cognition every two years. This included 9,948 older adults.

Among adults aged 65 to 84, those with diabetes and complete tooth loss had the highest rates of accelerated mental decline compared to those without either condition.

Those with diabetes aged 65 to 74 or those aged 65 to 84 with complete tooth loss also had faster cognitive decline.

But mental decline was most rapid in the 65- to 74-year-old age group, with both diabetes and complete tooth loss.

The researchers found no conclusive evidence that mental decline was associated with toothlessness and diabetes in adults aged 85 and older.

It was assumed that the less healthy members of the group died before their late 80s. Or it is possible that cognitive impairment was already greater in this age group.

Wu noted that the study is observational and cannot prove cause and effect.

Dr. Cyprien Rivier, a postdoctoral fellow in neurology at the Yale School of Medicine, while cautioning that he is not a diabetes expert, said the association between diabetes and periodontitis makes sense. Rivier was not involved in the investigation.

Experts know that inflammation leads to changes in the microarchitecture of the brain.

“We know that when there’s a high level of systemic inflammation, the white matter becomes a little more fragmented,” Rivier said.

This leads to poorer brain health and cognitive outcomes, he said.

Rivier noted that oral health is very important to other areas of the body, including heart health. For example, according to the American Heart Association, patients with heart valve problems should take antibiotics before certain dental procedures because bacteria can travel through the bloodstream.

“The effects of oral hygiene on the whole body are now really well defined,” Rivier said.

More studies are needed to assess these connections, but good dental health is a simple and important goal of improving health, Rivier said.

“It’s quite cheap. It’s pretty easy to improve oral health at the population level,” said Rivier.

According to the study authors, older adults with poor dental health and diabetes would benefit from cognitive screening by primary care providers.

The results of the study were published on March 12 Journal of Dental Research.

More information

The US National Institute on Aging is more concerned with cognitive health and older adults.

SOURCES: Bei Wu, PhD, associate dean for research, New York University Rory Meyers College of Nursing and associate director, NYU Aging Incubator, New York City; Cyprien Rivier, MD, MSc, Postdoctoral Fellow, Neurology, Yale School of Medicine, New Haven, Conn.; Journal of Dental ResearchMarch 12, 2023