While many people think that their oral health is separate from their overall health, more and more research is showing that the two are closely related. In fact, a recent study published in the Journal of Post-Acute and Long-term Care Medicine by researchers at New York University Rory Meyers College of Nursing has suggested a connection between tooth loss and dementia. In this blog post, we will first look at the issues individually, then provide a summary of the study and its results to explore this connection.
Tooth loss is a prevalent problem in older adults. In fact, the Centers for Disease Control and Prevention (CDC) note that as many as 1 in 6 adults over the age of 65 have no natural teeth. The most common cause of tooth loss in adults is severe gum disease (periodontitis). Luckily, however, there are dental prosthetic options available for individuals with missing teeth. Dentures are one commonly used prosthetic and are mentioned in the article. Dental implants are also commonly used to replace missing teeth, although there was no mention of them in the article.
Dementia is the term used to describe multiple symptoms associated with brain degeneration. It is characterized by impairments with thinking, memory, and decision-making. There are various different types of dementia out there, however Alzheimer’s disease is the most common and the most well-known type of dementia. The CDC reports that over 5 million people over the age of 65 are affected by dementia. Currently, there is no known cause of dementia, but risk factors include: age, genetics, race/ethnicity, past or present head injuries, smoking, and health conditions such as high blood pressure and high cholesterol.
Now that we know a little bit more about each condition, let’s take a look at how this new study found a connection. To determine if there was a significant relationship between tooth loss and dementia, researchers analyzed longitudinal studies of tooth loss and cognitive impairment. Specifically, 14 different studies including 37,074 adults and 4,689 cases of adults with diminished cognitive function were analyzed. The results of this analysis yielded the following conclusions:
- Adults with more tooth loss had a 1.48 times higher risk of developing cognitive impairment
- Adults with more tooth loss had a 1.28 times higher risk of being diagnosed with dementia, despite controlling for other factors
- Adults with missing teeth were more likely to be affected by cognitive decline if they did not have dentures (23.8% of individuals without dentures were more likely to have cognitive impairment, compared to only 16.9% of individuals with dentures.
- A larger amount of missing teeth was associated with a higher risk for cognitive decline (each additional missing tooth increased the risk of cognitive impairment by 1.4% and the risk of being diagnosed with dementia by 1.1%)
“…[the] relationship between the number of missing teeth and risk of diminished cognitive function substantially strengthens the evidence linking tooth loss to cognitive impairment, and provides some evidence that tooth loss may predict cognitive decline”-Xiang Qi, a doctoral candidate at NYU Meyers
Although the findings in this study indicate a link between tooth loss and cognitive decline, researchers are still unsure about what causes it. There are currently three hypotheses that they have mentioned, including:
- Nutritional deficiencies caused by an impaired chewing ability due to missing teeth
- A possible connection between gum disease and cognitive decline
- Life-long socioeconomic challenges that are risk factors for both tooth loss and cognitive decline
“Our findings underscore the importance of maintaining good oral health and its role in helping to preserve cognitive function”Bei Wu, PhD and the study’s senior author
Researchers have identified a link between tooth loss and dementia that suggests tooth loss is another risk factor. Despite the fact that this link is still being evaluated, researchers are urging people to improve or maintain their oral health as a way of decreasing their individual risk of developing cognitive decline and/or dementia.
Dr. Alina Huang has been practicing dentistry in Manhattan for the last eight years. She was born in New York City, and raised in California where she received her Bachelor’s degree at UCLA, and her D.D.S. at the University of the Pacific in San Francisco. She then made her return to NYC where she completed her General Practice Residency at Montefiore Medical Center and has been working in private practice ever since. She continues her learning by attending courses to stay current with the latest advancements in dentistry and refine her skills.