New report explores the critical link between oral health and Alzheimer’s disease

Imagine if a simple dental checkup could be a key to preserving memories and cognitive function as we age. It sounds almost too good to be true, but a new report points to a link between oral health and the risk of being diagnosed with dementia.

The report from CareQuest Institute¹ highlights research that shows poor oral health—particularly periodontal disease—can increase the risk of being diagnosed with Alzheimer’s disease and related dementias (ADRD). The aggregated findings indicate that having an infection of periodontal bacteria, notably Porphyromonas gingivalis, may trigger the accumulation of beta-amyloid protein in the brain, contributing to cognitive decline and memory loss associated with ADRD. Additionally, adults with ADRD, especially at advanced stages, face challenges in maintaining oral hygiene, leading to broader oral health issues.

The connection between oral health and ADRD

Across the US, one in nine older adults, accounting for 6.9 million adults aged 65 and older,² were diagnosed with Alzheimer’s disease in 2023. ADRD has a disproportionate impact across race and gender—for example, individuals identifying as Black or Hispanic are at a higher risk of being diagnosed with ADRD than white individuals. And it is estimated that by 2060, the number of Hispanic individuals diagnosed with ADRD will increase by seven times, and by four times among Black individuals.³

Meanwhile, periodontal disease, characterized by inflammation and infection of the gums, has been linked to several systemic conditions, including diabetes⁴ and cardiovascular disease.⁵

Recent research⁶ has expanded those conditions to include ADRD. Studies have found that older adults with antibodies against P. gingivalis are significantly more likely to be diagnosed with ADRD than those without antibodies. This association is thought to be due to the brain’s response to the periodontal bacteria. A buildup of beta-amyloid protein (plaque) occurs as a response to infection with P. gingivalis. These plaques can block brain cells from communicating with each other, leading to memory loss and confusion, hallmark symptoms of Alzheimer’s disease.

Oral health challenges in ADRD patients

Individuals with Alzheimer’s disease encounter significant barriers to maintaining oral health. This is particularly true in advanced stages of the disease when cognitive decline impairs their ability to perform routine oral care tasks. They may struggle to understand or complete their oral care routine, report oral pain, or cooperate with oral health-care providers.

According to the report, compared to adults aged 50–80 without Alzheimer’s disease, adults of the same age with Alzheimer’s disease have worse periodontal health across several markers,⁷ including more plaque, deeper gingival pockets, more bone loss around the teeth, and more gingival bleeding.

Moreover, the financial burden associated with dental care is notably higher for individuals with ADRD.⁸ They often incur higher costs for restorative and surgical procedures compared to those without the disease. This financial strain underscores the urgent need for preventive oral health measures and the integration of oral health into overall health.

The importance of preventive care

Regular dental checkups and maintaining good oral hygiene can play a crucial role in mitigating the risk of developing dementia. For older adults—especially those at higher risk for ADRD—proactive oral health care can play a part in maintaining cognitive health.

ADRD primarily impacts older adults, many who are enrolling in Medicare for the first time. But because traditional Medicare does not cover most dental services, nearly 25 million older Americans⁹ lack access to dental health care. Around the same number of Medicare enrollees haven’t visited a dentist in 12 months.⁹ That number is closer to 70% for Black, Hispanic, and lower-income Medicare beneficiaries.

This has profound implications for the health and well-being of older adults who often need to make difficult financial trade-offs such as whether to go to the dentist or pay their mortgage and utility bills.

Integrating oral health into broader health-care policies is essential. Ensuring equitable access to preventive oral health care for all older Americans by adding an adult dental benefit to Medicare coverage¹⁰ can help reduce the incidence and progression of ADRD for millions of people.

Addressing knowledge gaps

While the link between poor oral health and ADRD is increasingly evident, there are still knowledge gaps. Large-scale clinical trials⁶ are necessary to determine whether periodontal treatment can reduce the risk of developing ADRD or mitigate its symptoms. Researchers should also examine the association between oral and ADRD-related health-care costs to provide evidence for the benefits of including oral health care in the management of dementia.

Long-term studies using comprehensive electronic health records or clinical trial registries could provide deeper insights into factors influencing the relationship between oral health and dementia.

Emerging research on the connection between oral health and Alzheimer’s disease underscores the importance of maintaining good oral hygiene throughout life. As we continue to explore this link, the potential to reduce the burden of dementia through improved oral health practices offers a promising avenue for enhancing the quality of life for millions of individuals and their caregivers.

Editor’s note: This article first appeared in Clinical Insights newsletter, a publication of the Endeavor Business Media Dental Group. Read more articles and subscribe.

References

1. Poor oral health may contribute to the risk of dementia. CareQuest Institute. April 24, 2024. https://www.carequest.org/resource-library/poor-oral-health-may-contribute-risk-dementia
2. 2024 Alzheimer’s disease facts and figures. Special report: Mapping a better future for dementia care navigation. Alzheimer’s Association. 2024. https://www.alz.org/media/Documents/alzheimers-facts-and-figures.pdf
3. Minorities and women are at a greater risk of Alzheimer’s disease. Division of Population Health, National Center for Chronic Disease Prevention and Health Promotion. Centers for Disease Control and Prevention. Alzheimer’s Disease and Healthy Aging. Reviewed August 20, 2019. https://www.cdc.gov/aging/publications/features/Alz-Greater-Risk.html
4. Periodontal treatment associated with decreased diabetes-related treatment costs. CareQuest Institute for Oral Health. June 6, 2024. https://www.carequest.org/resource-library/periodontal-treatment-associated-decreased-diabetes-related-treatment-costs
5. The relationship between oral health and heart disease. CareQuest Institute for Oral Health. December 18, 2023. https://www.carequest.org/about/blog-post/relationship-between-oral-health-and-heart-disease
6. Large study links gum disease with dementia. National Institute on Aging. National Institutes of Health. July 9, 2020. https://www.nia.nih.gov/news/large-study-links-gum-disease-dementia
7. Martande SS, Pradeep AR, Singh SP, et al. Periodontal health condition in patients with Alzheimer’s disease. Am J Alzheimers Dis Other Demen. 2014;29(6):498-502. doi:10.1177/1533317514549650
8. Li M, Donkor IK, Shao R, et al. Effects of Alzheimer’s disease and related dementias on dental care usage and economic burden in older adults: a cross-sectional study. BMJ Open. 2023;13(6):e068944. doi:10.1136/bmjopen-2022-068944
9. Why we (still) need to add dental to Medicare. CareQuest Institute for Oral Health. November 15, 2021. https://www.carequest.org/resource-library/why-we-still-need-add-dental-medicare
10. Another billion reasons for a Medicare dental benefit. CareQuest Institute for Oral Health. September 30, 2022. https://www.carequest.org/resource-library/another-billion-reasons-medicare-dental-benefit