periodontitis-related bacteria & their role in alzheimer's disease

As the predominant dementia variant in 50-75% of cases and a global health concern with numerous implications for communities, alzheimer s disease (ad) is the primary contributor to dependency and incapacity in aged people. the prevalence of ad is estimated to be doubled every five years after age 65. the worlds alzheimer report 2018 found ad in two-thirds of 50 million patients with dementia around the globe. in 2019, different types of dementia, including ad, constituted the 7th major cause of mortality, especially in older adults and women. as a progressive neurodegenerative condition, ad causes irreparable memory loss, language, learning, and thinking disorders, and ultimately death. the prevalence of ad in the us is anticipated to increase from 6.2 million in 2022 to 13.85 million in 2060 in patients aged at least 65 years.despite the clarification of the pathophysiological pathway of ad, new molecular and cellular pathways have also been identified to determine the exact mechanism. it is pathologically, characterized by senile plaques consisting of β-amyloid and neurofibrillary tangles (nfts) hyperphosphorylated tau as a key microtubule-associated protein. poor oral hygiene with immune deficiency in the elderly causes periodontal diseases and chronic inflammation through bacterial imbalance in the mouth. periodontitis through inflammatory pathways can be a risk factor for exacerbation of cognitive impairment in ad patients. toxic bacterial products, including the bacteria themselves, can reach the central nervous system through the bloodstream and cause inflammatory responses. this presentation is conducted to discuss the relationship between ad and bacteria, as the risk factor, involved in periodontitis. it is recommended to integrate oral hygiene practices with routine health care of community members and patients with cognitive impairment and dementia. oral health programs should be designed for adults to prevent extra-neuronal inflammation and neurodegeneration until more research is done to determine the exact molecular mechanisms of ad and the molecular pathways associated with bacterial gingival infections, especially periodontitis.