Periodontitis is associated with cognitive impairment among older adults: analysis of NHANES-III

J Neurol Neurosurg Psychiatry. 2009 Nov;80(11):1206-11. doi: 10.1136/jnnp.2009.174029. Epub 2009 May 5.


Background: Periodontitis is ubiquitous and associated with serological evidence of exposure to periodontal organisms, systemic inflammation and vascular disease. Dementia is a major public health problem likely related to a complex interaction between genetics and diseases associated with systemic inflammation, including diabetes, smoking and stroke.

Methods: To assess relationships between systemic exposure to periodontal pathogens and cognitive test outcomes, data were analysed from the Third National Health and Nutrition Examination Survey (NHANES-III), a nationally representative cross sectional observational study among older adults. We included 2355 participants >or=60 years who completed measures of cognition and Poryphyromonas gingivalis IgG. Using SUDAAN, logistic regression models examined the association of P gingivalis IgG with cognitive test performance.

Results: Poor immediate verbal memory (<5/9 points) was prevalent in 5.7% of patients, and 6.5% overall had impaired delayed recall (<4/9); 22.1% had difficulty with serial subtractions (<5/5 trials correct). Individuals with the highest P gingivalis IgG (>119 ELISA Units (EU)) were more likely to have poor delayed verbal recall (OR 2.89, 95% CI 1.14 to 7.29) and impaired subtraction (OR 1.95, 95% CI 1.22 to 3.11) than those with the lowest (<or=57 EU), with dose-response relationships for both (p trend, delayed memory = 0.045, subtraction = 0.04). After adjusting for socioeconomic and vascular variables, these relationships remained robust for the highest P gingivalis IgG group (delayed verbal memory OR 3.01 (95% CI 1.06 to 8.53); subtraction OR 2.00 (95% CI 1.19 to 3.36)). In contrast, immediate verbal memory was not significantly associated with P gingivalis.

Conclusion: A serological marker of periodontitis is associated with impaired delayed memory and calculation. Further exploration of relationships between oral health and cognition is warranted.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Aged
  • Cognition
  • Cognition Disorders / complications
  • Cognition Disorders / epidemiology*
  • Cross-Sectional Studies
  • Female
  • Humans
  • Immunoglobulin G / blood
  • Male
  • Middle Aged
  • Nutrition Surveys
  • Periodontitis / complications
  • Periodontitis / epidemiology*
  • Periodontitis / immunology
  • Porphyromonas gingivalis / immunology


  • Immunoglobulin G