Association Between Periodontitis and Mild Cognitive Impairment, Alzheimer's Disease, and Dementia: An Umbrella Review With Evidence Stratification.

AIM: The present umbrella review aims to assess the association between periodontitis and mild cognitive impairment(MCI), Alzheimer's disease and dementia.

METHODS AND

RESULTS

MEDLINE(via PubMed), Scopus, EMBASE, Google Scholar, and Cochrane Library was searched. Risk of Bias(ROB) was performed using Risk of Bias in Systematic Reviews (ROBIS) tool. Metaumbrella software was used for performing quantitative analysis, evidence stratification and GRADE analysis. 12 of the 14 included studies were judged to have a high ROB, while two systematic reviews and meta-analyses (SRMAs) demonstrated a low ROB. Individuals with periodontitis had a 1.651 times higher risk of developing MCI (95% CI = 1.391 to 1.96; I2 = 0%; P < 0.001), a 1.525 times higher risk of Alzheimer's disease (95% CI = 1.149 to 2.023; I2 = 85.877%; P < 0.001), and a 1.535 times higher risk of dementia (95% CI = 1.119 to 2.107; I2 = 82.972%; P < 0.001), all supported by Class IV evidence. Furthermore, severe periodontitis was associated with a 2.138 times higher risk of MCI (95% CI = 1.59 to 2.875; I2 = 0%; P < 0.001), while moderate or severe periodontitis was associated with a 2.048 times higher risk of dementia (95% CI = 1.45 to 2.893; I2 = 0%; P < 0.001), supported by Class IV and Class III evidence, respectively. Despite these associations, the certainty of evidence for all outcomes was rated as very low according to the GRADE assessment.

CONCLUSION

A significant association was found between periodontitis and MCI, Alzheimer's disease and dementia with a "very low" evidence certainty.