Understanding the Link between Oral Hygiene and Cognitive Function in Geriatric Chinese-Americans

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The Journal of the American Geriatrics Society recently published a study titled, “Oral Health Symptoms and Cognitive Function Among US Community-Dwelling Chinese Older Adults,” which examined how poor oral health impacts cognitive function in geriatric Chinese adults living in the United States. The studied showed that adults who report poor oral hygiene are much more likely than adults reporting good oral hygiene to suffer from impaired cognitive function. This discovery could support a link between poor oral hygiene and geriatric conditions like dementia and Alzheimer’s, though more research would need to be done to solidify this correlation.

The Goal & Research Sample

This is not the first study to examine the link between oral hygiene and cognitive function. Previous studies have suffered from small sample sizes and inconsistent conclusions. The goal of this study was to hone in on a specific demographic and use a large enough sample size to come to a concrete solution.

The researchers targeted geriatric Chinese Americans for their study based on the following facts:

  • Racial minorities are particularly susceptible to poor oral hygiene due to low socioeconomic status and language barriers.
  • Chinese Americans are one of the fastest-growing minority populations in the United States
  • Cognitive conditions such as dementia and Alzheimer’s are most notable in geriatric communities.

Petrovsky et al. used a research sample of 2,713 Chinese Americans from geriatric communities. The sample size was 58.4% female and 41.6% male, with a median age of 72.6 years.

The Process

A team of researchers from the PINE (Population Study of Chinese Elderly) team conducted two waves of research in which they asked the same questions approximately two years apart in order to see how symptoms progressed among participants. Data was only used from participants who were able to complete both waves of research.

First, participants were asked to discuss any oral health symptoms they have suffered from in the past and/or had oral health symptoms they were currently suffering from. Researchers distinguished between “teeth” symptoms and “gum” symptoms based on the language participants used during the interview.

After interviewing them about their oral health symptoms, researchers conducted five tests to evaluate the cognitive function of participants. The tests they used were:

  • The Symbol Digit Modalities Test (SDMT): A test which measures executive function by examining how well participants answer 11 questions comparing numbers and symbols in a 90-second period of time.
  • The East Boston Memory Test: A test used to assess episodic memory by examining how well participants remembered short stories immediately after they were told and then again after a delay.
  • Digit Span Backwards: A common test for dementia and deliria, which is used to assess working memory.
  • Delayed Recall Test and the Mini-Mental State Evaluation: Two additional tests which were used in conjunction with the first three tests to assess global cognitive function.

The five tests were given once in 2012-2013, and then again in 2015. The difference between a participant’s composite scores during the two different testing periods was used to evaluate the loss of cognitive function.

The Results

The results of the study showed a definitive correlation between poor oral health and loss of cognitive function. This is similar to findings in a previous study, which showed that losing teeth could lead to impaired cognitive function. The implications of this study could help scientists understand more about oral hygiene’s role in the development of conditions like dementia among geriatric patients.

Implications for Further Research

More research on the connection between cognitive function and oral hygiene could help policy-makers create informed healthcare decisions. Based on the findings in this study, help further research could include:

  • Research which uses oral examinations rather than self-reporting to measure oral health
  • Research involving different minority demographics
  • Research examining oral hygiene and cognitive impairments outside the United States

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