IADR Abstract Archives
Periodontitis and Brain Magnetic Resonance Imaging Markers of Alzheimer’s Disease
Objectives: A range of findings on multimodal brain magnetic resonance imaging (MRI) is associated with Alzheimer’s disease (AD) and related dementias (ADRD). Earlier studies have linked poor oral/periodontal health with cognitive decline/ADRD. We examined the association between clinical, microbiological and host response features of periodontitis and MRI findings related to ADRD in the Washington Heights-Inwood Columbia Aging Project Ancillary Study of Oral Health.
Methods: 486 participants underwent full-mouth periodontal examination, subgingival microbial plaque collection, and contemporaneous brain MRI. Microbial samples were analyzed using checkerboard DNA-DNA hybridization and 16sRNA sequencing. Serum IgG levels against periodontal microbiota were assessed using checkerboard immunoblotting. MRI features included presence of cerebral microbleeds, white matter hyperintensities (WMH), hippocampal volume, supratentorial white matter volume, entorhinal cortex volume (ECv), and a composite measure of cortical thickness in areas prone to AD-associated neurodegeneration (“AD signature”). Multiple regression analyses used periodontitis features as independent and MRI features as dependent variables, adjusting for age, sex, race, education, diabetes, hypertension, cardiovascular disease, smoking and APOE4 genotype.
Results: In fully adjusted models, having more teeth was associated with lower WMH, higher ECv, and less cortical thinning. A higher extent of periodontitis (% of teeth with attachment loss≥3mm) was associated with more microbleeds, more WMH, lower ECv, and more cortical thinning. In checkerboard-based analyses, subgingival levels of Tannerella forsythia were negatively associated with ECv, and levels of Veillonella parvula and Actinomyces naeslundii were negatively associated with WMH. Sequencing-based analyses identified several genera that were differentially associated with volumetric MRI outcomes. Likewise, differential associations emerged between serum IgG responses to specific periodontal bacteria and individual MRI outcomes.
Conclusions: In an elderly cohort, clinical, microbiological and serological features of periodontitis were cross-sectionally associated with MRI findings related to ADRD after adjustment for multiple AD risk factors. Further investigation of causal associations is warranted.
Methods: 486 participants underwent full-mouth periodontal examination, subgingival microbial plaque collection, and contemporaneous brain MRI. Microbial samples were analyzed using checkerboard DNA-DNA hybridization and 16sRNA sequencing. Serum IgG levels against periodontal microbiota were assessed using checkerboard immunoblotting. MRI features included presence of cerebral microbleeds, white matter hyperintensities (WMH), hippocampal volume, supratentorial white matter volume, entorhinal cortex volume (ECv), and a composite measure of cortical thickness in areas prone to AD-associated neurodegeneration (“AD signature”). Multiple regression analyses used periodontitis features as independent and MRI features as dependent variables, adjusting for age, sex, race, education, diabetes, hypertension, cardiovascular disease, smoking and APOE4 genotype.
Results: In fully adjusted models, having more teeth was associated with lower WMH, higher ECv, and less cortical thinning. A higher extent of periodontitis (% of teeth with attachment loss≥3mm) was associated with more microbleeds, more WMH, lower ECv, and more cortical thinning. In checkerboard-based analyses, subgingival levels of Tannerella forsythia were negatively associated with ECv, and levels of Veillonella parvula and Actinomyces naeslundii were negatively associated with WMH. Sequencing-based analyses identified several genera that were differentially associated with volumetric MRI outcomes. Likewise, differential associations emerged between serum IgG responses to specific periodontal bacteria and individual MRI outcomes.
Conclusions: In an elderly cohort, clinical, microbiological and serological features of periodontitis were cross-sectionally associated with MRI findings related to ADRD after adjustment for multiple AD risk factors. Further investigation of causal associations is warranted.