Diet Quality and Advanced Periodontitis in Relation to Serum CRP Levels: An 11‐Year Follow‐Up Study

ABSTRACT This study aimed to evaluate the combined association of diet and advanced periodontitis with serum high‐sensitivity C‐reactive protein (hs‐CRP) levels at baseline and after 11 years. Study participants ( n = 3058 at baseline and n = 3007 at follow‐up) were drawn from the Finnish population‐based Health 2000 and 2011 surveys. Baltic Sea Diet Score (BSDS), Dietary Inflammatory Index, and periodontal status were used as exposure variables, with hs‐CRP serum levels as the outcome. Baseline CRP levels in participants, categorized into four groups according to exposure variables, were compared with the Kruskal–Wallis test. The association of dietary indices and advanced periodontitis with serum CRP levels after 11 years of follow‐up was analyzed with linear regression. Participants with advanced periodontitis (at least one tooth with ≥ 6 mm pocket depth) had higher hs‐CRP levels in serum at baseline, in comparison to controls. The concurrent exposure to low BSDS or proinflammatory diet and advanced periodontitis was not associated with further increase in serum CRP levels. At an 11‐year follow‐up, unadjusted regression models demonstrated associations between elevated CRP levels and advanced periodontitis ( β = 0.19; 95% CI 0.08–0.31 and β = 0.20; 95% CI 0.09–0.31) or advanced periodontitis combined with low BSDS ( β = 0.23; 95% CI 0.09–0.37) or proinflammatory diet ( β = 0.18; 95% CI 0.02–0.34). The statistically significant differences disappeared after controlling for confounding factors. In conclusion, combined exposure to low BSDS or a proinflammatory diet and advanced periodontitis was not significantly associated with elevated hs‐CRP levels compared to single risk factor exposure.