AbstractBackgroundIncreasing evidence links periodontal microbiota to several systemic conditions, including high blood pressure (BP). Antibodies to oral pathogens can be considered an indirect assessment of periodontal bacterial burden. We aimed at assessing the relationship between systemic exposure to periodontal microbiota, expressed in terms of relative antibodies, and BP, using data from the third National Health and Nutrition Examination Survey (NHANES III).MethodsWe analyzed cross‐sectional, nationally representative data from 7,928 adults aged ≥40 years who underwent determination of BP and serum antibodies to 21 periodontal microorganisms. BP was examined as both continuous (mmHg) and binary (≷130/80 mmHg, i.e. normal/controlled or high/uncontrolled BP) variables. Pearson and Spearman correlations restricted maximum likelihood, crude and adjusted generalized additive models, and a machine learning approach based on gradient boosting modeling were combined to verify any association between antibodies to periodontal microbiota and BP.ResultsAntibodies toCampylobacter rectus, Veillonella parvula, Prevotella melaninogenicawere consistently associated with high/uncontrolled BP by about +3 mmHg of systolic and +2 mmHg of diastolic BP and with 10% to 13% higher odds of high/uncontrolled BP, as well as with more active periodontal disease and greater changes in clinical parameters of periodontitis. Antibodies toC. rectusresulted in the strongest association with BP.ConclusionsThere is an association between systemic exposure to periodontal microbiota and BP. Understanding the pathogenetic mechanisms that shape such relationships, and the relative potential impact on personalized medicine, is the challenge of future research.