Summary: A new study has found that diabetes and complete tooth loss accelerate cognitive decline in older people. The study highlights the importance of regular dental visits, adherence to diabetes treatment, and cognitive screenings for people with both conditions.
Diabetes and tooth loss contribute to worse cognitive function and more rapid cognitive decline in older adults, according to a new study published in a special issue of the Journal of Dental Research focused on aging and oral health.
“Our findings underscore the importance of dental care and diabetes management for older adults in reducing the devastating personal and societal costs of Alzheimer’s disease and other related dementias,” said Bei Wu, vice-president dean of research at NYU Rory Meyers College of Nursing and co-director of the NYU Aging Incubator, as well as the lead author of the study.
Diabetes is a known risk factor for cognitive decline and dementia. Many of the hallmarks of diabetes – high blood sugar, insulin resistance, inflammation and related heart disease – are thought to contribute to changes in the brain.
A growing body of research has found a similar link between poor oral health, particularly gum disease and tooth loss, and cognitive impairment and dementia. Like diabetes, inflammation plays a key role in gum disease, and these inflammatory processes can contribute to cognitive decline. Additionally, sore gums and missing teeth can make chewing difficult, leading to dietary changes that can lead to nutritional deficiency.
Nutritional deficiency, which can also be aggravated by impaired glucose tolerance and insulin sensitivity in diabetes, is another risk factor for cognitive impairment and dementia.
“Poor oral health, diabetes and cognitive decline are all linked, and we are beginning to understand how they can influence and exacerbate each other,” Wu said.
While diabetes and missing teeth are risk factors for dementia, little research has focused on the effects of these two conditions during cognitive decline. To fill this gap, Wu and his colleagues turned to the University of Michigan Health and Retirement Study, analyzing 12 years of data (2006-2018) from the longitudinal study to observe changes cognitive over time.
The researchers included 9,948 seniors grouped by age (65-74, 75-84, and 85+) in their analysis. The health and retirement study included measures of memory and cognitive function, assessed every two years, as well as questions about tooth loss, diabetes and other health and demographic factors. In this analysis, the researchers were particularly interested in older people who had lost all their teeth.
They found that people aged 65 to 84 with both diabetes and complete tooth loss had worse cognitive function than their counterparts without either condition.
Over time, adults aged 65 to 74 with diabetes only experienced accelerated cognitive decline, and those aged 65 to 84 without teeth also experienced accelerated cognitive decline, but adults aged 65 to 74 years with both diabetes and complete tooth loss had the fastest rate of cognitive decline.
The relationship between diabetes, tooth loss and cognitive decline was inconclusive for adults aged 85 and over, which may be explained by the fact that this group has greater overall cognitive impairment, potentially in better health (as people in poor health may be less likely to survive to their late 80s), or perhaps having more experience managing their diabetes.
For older adults with both poor oral health and diabetes, researchers emphasize the importance of regular dental visits, adherence to diabetes treatment and self-care to control blood sugar levels, and cognitive screenings in primary care settings.
“Access to dental care for older adults, especially those with diabetes, is critical, and healthcare providers should educate their patients about the link between oral health and cognition,” Wu said. .
Funding: Other study authors include Chenxin Tan and Xiang Qi of NYU Meyers, Angela Kamer of NYU College of Dentistry, Mark Schwartz of NYU Grossman School of Medicine, Huabin Luo of East Carolina University and Brenda Plassman, Frank Sloan and Mackenzie Martinez of Duke University. The research was funded in part by the National Institutes of Health (R56AG067619, P30AG059304, and P50MD017356).
The summary was generated via ChatGPT AI technology
About this cognitive research news
Author: Rachel Harrison
Contact: Rachel Harrison – NYU
Picture: Image is in public domain
Original research: Free access.
“Diabetes, edentulism and cognitive decline: a 12-year prospective analysis” by Bei Wu et al. Journal of Dental Research
Diabetes, edentulism and cognitive decline: a 12-year prospective analysis
Diabetes mellitus (DM) is a recognized risk factor for dementia, and growing evidence shows that tooth loss is associated with cognitive impairment and dementia. However, the effect of the co-occurrence of DM and edentulism on cognitive decline is understudied.
This 12-year cohort study aimed to assess the effect of co-occurrence of DM and edentulism on cognitive decline and to examine whether the effect differs by age group.
Data are from the Health and Retirement Study from 2006 to 2018. The study sample included 5,440 adults aged 65-74, 3,300 aged 75-84 and 1,208 aged 85 or older. A mixed-effects linear regression was used to model rates of cognitive decline stratified by age cohorts.
Compared with their counterparts without diabetes or edentulism at baseline, adults aged 65 to 74 years (β = −1.12; 95% confidence interval (CI), −1.56 to −0.65; P < 0.001) and those aged 75 to 84 with both conditions (β = −1.35; 95% CI, −2.09 to −0.61; P < 0.001) had poorer cognitive function. For the rate of cognitive decline, compared to those who had neither in the same age cohort, those aged 65 to 74 with both conditions declined at a higher rate (β = -0.15; 95% CI, -0.20 to -0.10; P < 0.001).
Diabetes alone caused accelerated cognitive decline in people aged 65 to 74 years (β = -0.09; 95% CI, -0.13 to -0.05; P <0.001); edentulism alone caused an accelerated decline in people aged 65 to 74 years (β = -0.13; 95% CI, -0.17 to -0.08; P < 0.001) and adults aged 75 to 84 (β = −0.10; 95% CI, −0.17 to −0.03; P < 0.01).
Our study reveals that the co-occurrence of DM and edentulism led to deterioration of cognitive function and more rapid cognitive decline in people aged 65-74 years.