Periodontitis and periodontal inflamed surface area in context of plant-based dietary patterns: Insights from the Hamburg City Health Study

Nutrition is a modifiable risk factor of periodontitis. Evidence for dietary scores reflecting current dietary behavior and relevant periodontitis staging in epidemiological studies remains limited. In n = 10,929 participants from a population-based cohort, we examined plant-based dietary patterns and the periodontal inflamed surface area (PISA), as well as periodontitis, according to the 2017 American Academy of Periodontology/European Federation of Periodontology periodontitis classification. Participants underwent full-mouth dental and periodontal examination. We assessed diet with a validated food-frequency questionnaire and determined a plant-based diet index (PDI), a healthful PDI (hPDI), and an unhealthful PDI (uPDI). Each dietary score and their association with periodontitis and PISA were analyzed with regression models, adjusted for age, sex, education, smoking, diabetes, and body mass index. Mediation analyses investigated systemic inflammation, quantified with hsCRP, in the association between each dietary score and periodontitis. The prevalence of Stage IV periodontitis was higher in individuals with higher uPDI scores. In fully adjusted regression analyses, higher PDI and hPDI scores were significantly associated with decreased odds of Stage IV periodontitis (adjusted OR = 0.85, 95%CI: 0.75–0.97, p = 0.014; adjusted OR = 0.86, 95%CI: 0.77–0.95, p = 0.004, respectively). A higher hPDI score was associated with a lower PISA (β = 0.95, 95% CI: 0.91–0.00, p = 0.008), a higher uPDI score with higher PISA (β = 1.08, 95% CI: 1.03–1.12, p < 0.001). Mediation analysis revealed a partial contribution by hsCRP in the association of PDI (13%), hPDI (11%), and uPDI (8%) with periodontitis. The inverse association between plant-based diet, periodontitis and PISA suggests potential benefits of plant-based foods for periodontal health.