The association between periodontitis and lung function: Results from the National Health and Nutrition Examination Survey 2009 to 2012

We aimed to explore the association between periodontitis and lung function in the United States.The data was based on the National Health and Nutrition Examination Survey (NHANES) 2009 to 2012. Periodontitis was defined following the CDC/AAP (Centers for Disease Control and Prevention/American Academy of periodontology) classification. Lung function measurements included forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio. Linear regression and binary logistic regression were used to explore the association between periodontitis and lung function measurements. Restricted cubic spline was used to assess the dose-response relationships between the mean attachment loss (AL), the mean probing depth (PD) and spirometry-defined airflow obstruction (FEV1/FVC <0.7).A total of 6313 adults aged 30 years or older were included. Compared to those with non-periodontitis, the multivariate-adjusted odds ratios (ORs) of airflow obstruction for moderate and severe periodontitis were 1.38 (95% CI: 1.01 to 1.75) and 1.47 (95% CI: 1.06 to 2.01), the β coefficients of FEV1 for moderate and severe periodontitis were -130.16 (95% CI: -172.30 to -88.01) and -160.46 (95% CI: -249.94 to -70.97), the β coefficients of FVC for moderate and severe periodontitis were -100.96 (95% CI: -155.08 to -46.85) and -89.89 (95% CI: -178.45 to -1.33), the β coefficients of FEV1/FVC for moderate and severe periodontitis were -0.01 (95% CI: -0.02 to -0.01) and -0.02 (95% CI: -0.03 to -0.01). In stratified analyses, the multivariate-adjusted ORs of airflow obstruction for the moderate and severe periodontitis were 1.27 (95% CI: 0.84 to 1.93) and 2.31 (95% CI: 1.10 to 4.83) in former smokers, 1.84 (95% CI: 1.03 to 3.30) and 1.79 (95% CI: 1.02 to 3.16) in current smokers, with no significant association observed in never smokers. Mean clinical AL and mean PD were negatively associated with FEV1, FVC, and FEV1/FVC in never, former, and current smokers. Dose-response relationship analysis showed that the risk of airflow obstruction increased with increasing mean clinical AL and mean PD, and showed a non-linear dose-response relationship.Our study suggested that moderate and severe periodontitis might be associated with the decline of lung function in the United States of America.