Parkinson's disease and Porphyromonas gingivalis levels: a case-control study

This study aimed to evaluate the clinical and epidemiological aspects of the association between Parkinson's disease (PKD) and periodontitis (PE), including the quantification of Porphyromonas gingivalis and the influence of different risk variables on this association.

This case-control study included 172 individuals: 86 cases (PKD) and 86 controls (without any neurodegenerative disease). Participants underwent a complete periodontal examination (plaque index and probing depth), and clinical subgingival sampling was conducted to quantify Porphyromonas gingivalis counts. The association between PKD and PE was evaluated through univariate and binary logistic regression analyses.

A high prevalence of PE (73.2%) was observed among individuals with PKD [OR=3.99 (2.00-7.59); p<0.001]. Variables that were significantly retained in the final binary logistic regression model for the occurrence of PKD were: PE (OR=3.23; p=0.003), mean P. gingivalis counts (OR= 3.39; p=0.036), lower number of teeth (OR= 2.21, p<0.001), low frequency of toothbrushing/day (OR=1.95; p=0.006), and bleeding on probing (OR=2.45; p<0.001). The significant positive correlations observed between P. gingivalis counts and clinical periodontal parameters were considered moderate to strong in individuals with PKD.

A strong association between PKD and PE was demonstrated, with risk increasing in parallel with the severity of periodontal involvement. Furthermore, individuals with PKD exhibited significantly higher levels of P. gingivalis compared to controls.