Periodontitis is a chronic inflammation that destroys periodontal tissues caused by the accumulation of bacterial biofilms that can be affected by environmental factors. This report describes an association study to evaluate the relationship of environmental factors to the expression of periodontitis using the National Health and Nutrition Examination Study (NHANES) from 1999–2004. A wide range of environmental variables (156) were assessed in patients categorized for periodontitis (n = 8884). Multiple statistical approaches were used to explore this dataset and identify environmental variable patterns that enhanced or lowered the prevalence of periodontitis. Our findings indicate an array of environmental variables were different in periodontitis in smokers, former smokers, or non-smokers, with a subset of specific environmental variables identified in each population subset. Discriminating environmental factors included blood levels of lead, phthalates, selected nutrients, and PCBs. Importantly, these factors were found to be coupled with more classical risk factors (i.e. age, gender, race/ethnicity) to create a model that indicated an increased disease prevalence of 2–4 fold across the sample population. Targeted environmental factors are statistically associated with the prevalence of periodontitis. Existing evidence suggests that these may contribute to altered gene expression and biologic processes that enhance inflammatory tissue destruction.

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Published in Scientific Reports, v. 9, article no. 8227, p. 1-11.

© The Author(s) 2019

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This work was supported by funding from the Center for Oral Health Research in the University of Kentucky, College of Dentistry and from P20GM103538 and UL1TR000117 from the National Institute of Health.

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Repository for the data, R code, and SAS code can be accessed at https://github.com/joshuawlambert/PinarEtal2018.

Supplementary information accompanies this paper at https://doi.org/10.1038/s41598-019-44445-3.

41598_2019_44445_MOESM1_ESM.docx (14 kB)
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