Periodontitis as a Modifiable Risk Factor for Dementia: A Nationwide Population-Based Cohort Study

Objectives: To determine whether periodontitis is a modifiable risk factor for dementia. Design: Prospective cohort study. Setting: National Health Insurance Research Database in Taiwan. Participants: Individuals aged 65 and older with periodontitis (n = 3,028) and an age- and sex-matched control group (n = 3,028). Measurements: Individuals with periodontitis were compared age- and sex-matched controls with for incidence density and hazard ratio (HR) of new-onset dementia. Periodontitis was defined according to International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes 523.3–5 diagnosed by dentists. To ensure diagnostic validity, only those who had concurrently received antibiotic therapies, periodontal treatment other than scaling, or scaling more than twice per year performed by certified dentists were included. Dementia was defined according to ICD-9-CM codes 290.0–290.4, 294.1, 331.0–331.2. Results: After adjustment for confounding factors, the risk of developing dementia was calculated to be higher for participants with periodontitis (HR = 1.16, 95% confidence interval = 1.01–1.32, P =.03) than for those without. Conclusion: Periodontitis is associated with greater risk of developing dementia. Periodontal infection is treatable, so it might be a modifiable risk factor for dementia. Clinicians must devote greater attention to this potential association in an effort to develop new preventive and therapeutic strategies for dementia.