The oral-systemic link between perio and Alzheimer’s: Are we educating our patients?

Imagine a world where we no longer fear Alzheimer’s disease (AD) as we age, or watch those we love trapped in their bodies as their minds are adversely affected. Recent studies have brought to the forefront the oral-systemic link between periodontal disease and the increased risk of developing AD. These studies provide more evidence for what we already preach to our patients—the connection between the oral inflammation process and the whole body.

For too many years, the mouth has been considered unrelated to the rest of the body in the eyes of the general public, and many times by the medical profession. We’ve all had patients tell us that changes in their medical history or medications don’t matter because they don’t have anything to do with their mouths. A lack of education on health connections could have detrimental effects for our patients. With more and more evidence coming out each year to establish the correlation between the mouth and systemic illnesses, we should be educating our patients on the link of periodontal disease pathogens and other inflammatory body responses.

The oral-systemic link

A study at Chung Shan Medical University concluded that individuals who had periodontal disease for more than 10 years were at a 70% higher risk of developing AD than their peers without periodontal disease. (1) The study additionally accounts for other factors associated with Alzheimer’s, such as heart disease, stroke, diabetes, and environmental factors.

Another study found that after inducing chronic periodontitis in mice, the periodontal pathogen Porphyromonas gingivalis (Pg)and/or its byproduct gingipain was present in brain tissues. Previous studies of the brains of deceased AD patients have already “strongly [suggested]” that Pg and and gingipain are translocated to the brain. (2) This animal study “strongly [suggests] that low grade chronic periodontal pathogen infection can result in the development of neuropathology that is consistent with that of AD.” (2) The periodontal pathogens had traveled in the bloodstream and crossed the blood-brain barrier. In addition, the authors noted that “periodontal bacteria may kick-start the development of Alzheimer’s disease.” (3)These examples provide more evidence that inflammatory responses from periodontal disease may affect more than just the mouth.

Effects of Alzheimer’s disease

AD affects the functioning of the brain by disrupting the connections between the neurons as well as reducing the overall function of synapses and causing cell death within the brain. As the cells die, the damage can be widespread and drastically affect the individual. The most commonly affected areas of the brain are the entorhinal cortex, the hippocampus, and the cerebral cortex, ultimately impairing memory, language, reasoning, and social behaviors. Over time, AD proves to be fatal as other areas of the brain governing vital systems are affected. People affected with AD often have more than one factor associated with brain change, including ministrokes and atherosclerosis of the arteries within the brain combined with chronic inflammation.(4)

When oral hygiene and periodontal care can be preventive factors in possibly delaying or eliminating the risk of developing AD, why wouldn’t one take their oral health a little more seriously?

According to the Alzheimer’s Association, every 65 seconds someone in the United States develops AD, which means one in 10 people over the age of 65 are affected. It is listed as the sixth leading cause of death in the United States, with diagnosis rates increasing 123% from 2000 to 2015. An astounding 5.7 million Americans are affected by the disease. It strikes women more than men with two thirds of cases being female. By the year 2050, it is expected to affect nearly 14 million Americans, and the costs can climb to 1.1 trillion dollars for Alzheimer’s and dementia care.To put it into perspective, AD kills more people than breast cancer and prostate cancer combined each year. (5)

Educating our patients

When we speak with our patients and recommend periodontal therapy to treat the oral disease process, are we also talking to them about associated risks? AD joins the list of known inflammatory diseases associated with periodontal disease, including cardiovascular disease and diabetes. Discuss family history with your patients. If there is a history of cognitive impairment, it may be the deciding factor the patient needs to accept your periodontal diagnosis and treatment. Watching a family member robbed of memories and forgetting loved ones is heartbreaking and stressful for those left behind. When oral hygiene and periodontal care can be preventive factors in possibly delaying or eliminating the risk of developing AD, why wouldn’t one take their oral health a little more seriously?

References

1. Chen CK, Wu YT, Chang YC. Association between chronic periodontitis and the risk of Alzheimer's disease: a retrospective, population-based, matched-cohort study. Alzheimers Res Ther. 2017;9(1):56. doi: 10.1186/s13195-017-0282-6.
2. Ilievski V, Zuchowska PK, Green SJ, et al. Chronic oral application of a periodontal pathogen results in brain inflammation, neurodegeneration and amyloid beta production in wild type mice. PLoS One. 2018;13(10):e0204941. doi: 10.1371/journal.pone.0204941.
3. Carey J. Periodontal disease bacteria may kick-start Alzheimer’s. Medical Xpress website. https://medicalxpress.com/news/2018-10-periodontal-disease-bacteria-kick-start-alzheimer.html. Published October 4, 2018.
4. What Happens to the Brain in Alzheimer's Disease? National Institutes of Health website. https://www.nia.nih.gov/health/what-happens-brain-alzheimers-disease.
5. Alzheimer’s Disease Facts and Figures. Alzheimer’s Association website. https://www.alz.org/alzheimers-dementia/facts-figures.

Jamie Collins, RDH, CDA, is a practicing clinical hygienist in Idaho and Washington states. She has been in the dental field for nearly 20 years, both as an assistant and hygienist. With a passion for patient care, especially patients with higher risk factors, she enjoys sharing the tips and tricks of the dental profession through speaking and writing. In addition to clinical practice, she is also an educator, has contributed to multiple textbooks and curriculum development, and is a key opinion leader. Contact her at [email protected].