Oral Health and Cognitive Decline in an Aging Population
Sonu Acharya, BDS, MDS; and Sheetal Acharya, BDS, MDS
As the global population ages, there is a growing recognition of the multifaceted impact of aging on various aspects of health and well-being. Oral ailments and conditions linked to the aging process increase the demand for preventive, restorative, and periodontal dental interventions. This holds particularly true for individuals aged 65 and above, specifically those facing economic disadvantages, belonging to racial or ethnic minority communities, or residing in institutions, experiencing disabilities, or being confined to their homes.1
An intricate interplay exists between cognitive decline and oral health within the aging population, underscoring how these two seemingly distinct realms are interconnected and mutually influential.2 By exploring the underlying mechanisms, shared risk factors, and potential implications, the dental profession can gain a deeper understanding of the importance of comprehensive geriatric care that addresses both cognitive well-being and oral health maintenance.3 In doing so, the way is paved for more holistic approaches to promote the overall quality of life for our aging population.
Intricate Links
Alzheimer's disease, a progressive neurodegenerative disorder that primarily affects cognitive functions, has far-reaching implications that extend beyond the realm of cognitive health. One often overlooked factor is the intricate connection between Alzheimer's disease and oral health. As individuals with Alzheimer's experience cognitive decline, their ability to maintain proper oral hygiene and manage oral care diminishes, leading to a range of oral health challenges. Furthermore, emerging research suggests a potential bidirectional relationship, where poor oral health might contribute to an increased risk of cognitive decline in susceptible individuals. Such exploration of the multifaceted interactions between Alzheimer's disease and oral health sheds light on the implications for both patient care and a broader understanding of the intricate links between systemic health and neurological disorders.4 By recognizing the significance of maintaining oral health in Alzheimer's patients and elucidating the potential pathways connecting these two domains, comprehensive care strategies can be developed that enhance the overall well-being and quality of life for those affected by this devastating disease.
The precise underlying cause of Alzheimer's disease, which is the predominant form of dementia, remains largely unknown, rendering it a challenging affliction to both prevent and treat. The complexity of its origin contributes to the intricacies associated with devising effective preventive measures and treatment strategies. Previous research has demonstrated a clear correlation between Alzheimer's disease and the Porphyromonas gingivalis bacterium, which is responsible for gum tissue degradation. Additionally, the enzyme produced by this bacterium, referred to as "gingipains," has also been identified in the brain tissue of individuals with Alzheimer's.5 Such investigations explore the potential mechanisms through which gum disease and the associated bacterial proteins could potentially foster the development of brain lesions. A study soon to be published in the Journal of Alzheimer's Disease underscores that nerve cells within the brain harbor a specific protein variant called "tau." When the tau encounters the gingipains enzyme, it disengages from the nerve cell.6 Upon release, the tau undergoes a physical transformation, manifesting as both coiled and uncoiled filaments. Subsequently, these tau filaments rejoin the nerve cell and integrate into a lesion termed "neurofibrillary tangles." Regrettably, these tangles culminate in the demise of the nerve cells.7
This essentially unveils a critical process: as a nerve cell succumbs and the tau protein is discharged into the brain, it might affix itself to healthy neighboring nerve cells. This cycle perpetuates, exacerbating brain damage as the ailment progressively spreads. An additional recent investigation examined the impact of the gingipains enzyme, liberated by the bacterium, on the genesis of amyloid-beta plaques. These plaques constitute another category of lesions, alongside the aforementioned tangles, that emerge in the brains of individuals with Alzheimer's disease.8 New research from the Forsyth Institute shows a link between periodontal (gum) disease and the formation of amyloid plaque, a hallmark of Alzheimer's disease.9 Gum disease possesses the capacity to induce modifications in brain cells termed "microglial cells," which assume the vital role of safeguarding the brain against amyloid plaque. This particular plaque constitutes a form of protein intricately linked to cell demise and cognitive regression in individuals with Alzheimer's. This study not only furnishes pivotal understanding regarding the traversal of oral bacteria to the brain but also sheds light on the role of neuroinflammation in the progression of Alzheimer's disease.10
Beyond Esthetics
The significance of maintaining oral health as one ages transcends mere esthetics. It preserves one's ability to eat, speak, and interact without discomfort or limitation. It is an embodiment of the interconnectedness between oral health and overall well-being. Furthermore, the oral cavity serves as a window to systemic health, offering insights into conditions that might otherwise remain concealed. In this journey, proactive steps take center stage. From adhering to meticulous oral hygiene practices to fostering a diet that nourishes both body and teeth, and from sustaining regular dental visits to embracing habits that support overall vitality, the choices individuals make contribute to the longevity and vitality of their oral health.11 These choices, though seemingly simple, collectively shape a trajectory that can greatly enhance people's quality of life as they age.
In the ever-evolving landscape of medical research and practice, the amalgamation of Alzheimer's disease and oral health serves as a poignant reminder that the human body's intricacies often defy conventional boundaries. As the dental profession strives to comprehend the nuanced relationship between these two domains, it opens the door to innovative treatments, enhanced patient care, and a more comprehensive understanding of the human experience in the face of Alzheimer's.
ABOUT THE AUTHOR
Sonu Acharya, BDS, MDS
Professor, Pediatric and Preventive Dentistry, Institute of Dental Sciences, Siksha ‘O' Anusandhan (SOA) (deemed to be) University, Bhubaneswar, Odisha, India; Private Practice, Bhubaneswar, Odisha; Fellow, International Association of Pediatric Dentistry
Sheetal Acharya, BDS, MDS
Senior Lecturer, Periodontology and Implantology, Kalinga Institute of Dental Sciences, KIIT University, Bhubaneswar, Odisha, India
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