Infection burden, periodontal pathogens, and their interactive association with incident all-cause and Alzheimer's disease dementia in a large national survey

Abstract

Introduction: Relationships and interplay of an infection burden (IB) and periodontal pathogens or periodontal disease (Pd) markers with Alzheimer's disease (AD) and all-cause dementia among US adults were examined.

Methods: Less than or equal to 2997 participants from the National Health and Nutrition Survey III were linked to CMS-Medicare [≥45 years (1988-1994); ≤30 years follow-up].

Results: Hepatitis C (hazard ratio = 3.33, p = 0.004) and herpes simplex virus 2 were strongly associated with greater all-cause dementia risk. Porphyromonas gingivalis and Streptococcus oralis were associated with greater AD risk at higher IB. The red-green periodontal pathogen cluster coupled with higher IB count increased the risk of all-cause dementia among minority racial groups. Pocket probing depth associated with dementia risk at lower IB in the overall sample.

Discussion: Select viruses and bacteria were associated with all-cause and AD dementia, while the IB interacted with Pd markers in relation to these outcomes.

Highlights: Interplay of infection burden (IB) and periodontal disease with dementia was tested. ≤2997 participants from NHANES III were linked to Medicare. Hepatitis C and herpes simplex virus 2 strongly associated with dementia risk. Tetanus sero-positivity increased Alzheimer's disease (AD) risk. Porphyromonas gingivalis and Streptococcus oralis associated with AD at higher IB. Red-green periodontal cluster at high IB, increased dementia in racial minorities. Pocket probing depth associated with dementia risk at lower IB.

Keywords: Alzheimer's disease; aging; dementia; infection burden; periodontal pathogens; periodontitis.

FIGURE 1

Participant flowchart. Note: Both phases: 1988‐1994. AD, Alzheimer's disease; CMS, Centers for Medicare and Medicaid Services; NHANES III, Third National Health and Nutrition Examination Surveys.