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Study Examines the Link Between Periodontitis and Cognitive Decline

Alexandria, VA, USA – A study examining the association between clinical, microbiological and host response features of periodontitis and MRI findings related to Alzheimer’s Disease and related dementias (ADRD) will be presented at the 101st General Session of the IADR, which will be held in conjunction with the 9th Meeting of the Latin American Region and the 12th World Congress on Preventive Dentistry on June 21-24, 2023, in Bogotá, Colombia.

The Interactive Talk presentation, “Periodontitis and Brain Magnetic Resonance Imaging Markers of Alzheimer’s Disease,” will take place on Wednesday June 21, 2023, at 8:10 a.m. Colombia Time (UTC-05:00) during the “Periodontal Research-Diagnosis/Epidemiology I” session.

The study by Panos N. Papapanou of the Columbia University College of Dental Medicine, New York, USA, carried out full-mouth periodontal examinations, subgingival microbial plaque collections, and contemporaneous brain MRIs on 486 participants. 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.

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.

The study concluded that 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.

About IADR
The International Association for Dental Research (IADR) is a nonprofit organization with a mission to drive dental, oral, and craniofacial research for health and well-being worldwide. IADR represents the individual scientists, clinician-scientists, dental professionals, and students based in academic, government, non-profit and private-sector institutions who share our mission. Learn more at