Is there a relationship between periodontitis and Alzheimer's disease? Systematic review and comparative analysis

Abstract

AbstractBackgroundAlzheimer’s disease is a neurodegenerative disease with unknown cause, being the first cause of dementia affecting 24 million people, which is set to double by 2040. Periodontitis is a multifactorial, inflammatory and chronic disease that causes the loss of the tooth’s support system; being the number one cause of tooth loss in adults. Both diseases are highly prevalent, making them an important public health issue. New studies have shown that there might be a relation between them.MethodSystematic review and comparative analysis of studies through a bibliographic search that included clinical trials, case‐control and cohort studies in humans, with objective tests for the diagnosis of both diseases. Excluding: descriptive studies or studies that didn’t focus on Alzheimer’s; studies that didn’t diagnose periodontitis clinically; sigle case studies; based on patients with syndromes; or evaluated exclusively the quality of life of the patients. From the 473 articles found only 9 fulfilled the inclusion and exclusion criteria.ResultOut of the 9 articles selected, 7 found a statistically significant difference between people with Alzheimer’s and without it in relation to periodontitis (Choi S et al, Ide M et al, de Suza T et al, Martande SS et al, Holmer J et al, Cestari JA at al, Aragón F et al). Chen CK et al didn’t find a statistical significance at the beginning (p=0.0547) but did in the 10 years follow‐up (p=0.00264). Tiisanoja A et al didn’t find a statistic significance (RR=1.54; IC=0.52‐4.56). However, when subjecting the article’s results to CI for the proportion analysis we discovered that only one study found this difference significant out of the 6 included.ConclusionThe most common oral problems in patients with Alzheimer’s were gingivitis, periodontitis, tooth loss, candidiasis, calculus. Although there seems to be a relationship between the two, further studies with larger populations and a better screening process for participants, are needed in order to truly assess whether there is a causal relationship between the two pathologies or not. One of the greatest limitations we encountered was the lack of homogeneity between the studies statistical tools, making it impossible to do a meta‐analysis.