Severe Periodontitis Linked to Increased Risk of Alzheimer's Dementia: Study

A new study published in The Journal of Evidence-Based Dental Practice found a strong association between periodontitis and dementia, with severe periodontitis emerging as a potential risk factor for Alzheimer's disease. Further timely treatment and prevention of periodontitis progression may help reduce the risk of developing dementia.

The hallmarks of dementia include a gradual deterioration in cognitive function and disruption of day-to-day functioning. Dementia is quite likely to emerge from cognitive impairment, which is a condition that falls between dementia and the usual cognitive loss of normal aging. Alzheimer's disease (AD) is the most prevalent form of dementia, accounting for 60–80% of all cases.

By 2030, 82 million individuals worldwide will receive a dementia diagnosis, and the disease will cost $2 trillion worldwide, placing a significant financial strain on families and society. In addition to being a prevalent long-term infectious and inflammatory oral condition, periodontal disease also plays a role in systemic illnesses.

The link between periodontal disease and dementia has received increasing attention in recent years. For instance, even after controlling for confounding variables, those with periodontitis were shown to have a greater risk of dementia than those without the condition. Even with deep lesions or significant bleeding, periodontal disease was not linked to cognitive test results, according to a cross-sectional research. There is ongoing debate on the link between dementia and periodontitis. Thus, DONG-HEE KIM and colleagues examined this correlation with a focus on the kind of dementia and the severity of periodontitis.

From the beginning until June 30, 2021, this research explored the PubMed, Web of Science, Embase, and gray literature (OpenGrey, ProQuest) databases. We then combined the results for a meta-analysis. To assess the strength of the relationships between periodontitis and dementia, odds ratios (ORs), hazard ratios (HRs), and 95% confidence intervals (CIs) were computed using fixed- or random-effects models.

11 cohort studies and thirteen case-control studies were chosen. With an OR of 2.26 and HR of 1.15, the analysis of full studies showed a correlation between dementia and periodontitis. The risk of dementia was substantially correlated with severe periodontitis, but not with less-than-moderate periodontitis, based on the severity of the condition.

The patients with severe periodontitis were especially at a 2.92-fold increased risk of cognitive impairment and a 6.87-fold increased risk of Alzheimer's dementia. Overall, there is a direct correlation between periodontitis and dementia, and severe periodontitis may be a risk factor for Alzheimer's dementia. 

Reference:

Kim, D.-H., & Han, G.-S. (2025). Periodontitis as a risk factor for dementia: A systematic review and meta-analysis. The Journal of Evidence-Based Dental Practice, 25(2), 102094. https://doi.org/10.1016/j.jebdp.2025.102094