Access to dental care is severely limited in low- and middle-income countries as well as in lower-income communities in the U.S. Photo by Steve Evans; reprinted with permission through Creative Commons. http://bit.ly/23C9ULB
Published April 19, 2016 under Research News
Better oral hygiene and regular dental visits may be associated with a slower rate of cognitive decline as people age, but the strength of the evidence is weak. These findings, published recently in the Journal of the American Society of Geriatrics by nursing and global health professor Bei Wu and her colleagues, come from the first systematic review of the medical literature to examine studies focused on oral health and cognition.
Researchers have questioned whether an association exists between oral health status and cognitive status in the elderly, possibly through a common inflammatory pathway. “Clinical evidence suggests that the frequency of oral health problems increases significantly in cognitively impaired elderly, particularly those with dementia,” said Wu. “In addition, many of the factors associated with poor oral health—such as poor nutrition and systemic diseases like diabetes and cardiovascular disease—are also associated with poor cognitive function.”
Researchers Reviewed Twenty Years of Studies
To look for a link between oral health and cognitive status, Wu and her colleagues analyzed relevant studies published between 1993 and 2013. The researchers identified 56 cross-sectional and longitudinal studies; 11 of the longitudinal studies examined the impact of oral health on change in cognitive health or dementia incidence, and five of those studies examined the reverse.
Some studies found that oral health measures such as number of teeth and periodontal disease were associated with increased risk of cognitive decline or incident dementia, while others did not find the association. Also, findings based on number or change in number of teeth or cavities are conflicting, and limited studies found periodontal conditions, such as gingivitis, were associated with poorer cognitive status or cognitive decline.
More Rigorous Studies Are Needed
“There is not enough evidence to date to conclude that a causal association exists between cognitive function and oral health,” said Wu. “For future research, we recommend that investigators gather data from larger and more population representative samples, use standard cognitive assessments and oral health measures, and use more sophisticated data analyses.”
Oral Health Disparities Are a Major Global Health Challenge
Oral health disparities reflect some of the greatest challenges in the United States and around the globe. Wu has published a number of studies demonstrating notable oral health disparities across racial and ethnic groups and income. She notes that access to dental care is severely limited in low- and middle-income countries as well as in lower-income communities in the U.S.
“Many of these communities do not have access to providers with expertise in oral health, and even if they do, the cost of the care is usually prohibitive,” she said. “As a result, many people living in these areas suffer from serious oral health problems.”
Given these challenges, the connection between cognitive function and oral health—if established more firmly through further research—would have significant global health implications.
Article: “Association between Oral Health and Cognitive Status: A Systematic Review.” Bei Wu, Gerda G. Fillenbaum, Brenda L. Plassman, and Liang Guo. Journal of the American Geriatrics Society; Published Online: April 2016 (DOI: 10.1111/jgs.14036).
This article was adapted with permission from the original press release issued by the Journal of the American Society of Geriatrics.
