BackgroundThe association between periodontitis and post-bronchodilator lung function is unclear. We aimed to determine the associations between symptoms of severe periodontitis (SSP) and post-bronchodilator lung function in the Chinese population.MethodsA cross-sectional study (China Pulmonary Health study) was conducted from 2012 to 2015 in a large Chinese nationally representative sample of 49,202 participants aged 20–89 years. Data on demographic characteristics and periodontal symptoms of participants were collected by questionnaire. Participants who had at least one of the two severe symptoms (tooth mobility and natural tooth loss) in the past year were defined to have SSP, which was set as one variable for analyses. Post-bronchodilator lung function data including forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were collected by spirometry.ResultsThe values of post-FEV1, post-FVC and post-FEV1/FVC of the participants with SSP were all significantly lower than the participants without SSP (allp< 0.001). SSP were significantly associated with post-FEV1/FVC < 0.7 (p< 0.001). In the multiple regression analyses, SSP were still negatively associated with post-FEV1(b = -0.04, 95%CI (-0.05 -0.03),p< 0.001), post-FEV1/FVC (b = -0.45, 95%CI (-0.63, -0.28),p< 0.001) and significantly associated with post-FEV1/FVC < 0.7 (OR = 1.08, 95%CI 1.01—1.16,p= 0.03) after full adjustment for potential confounders.ConclusionsOur data suggest that SSP were negatively associated with post-bronchodilator lung function in the Chinese population. Longitudinal cohort studies are needed to confirm these associations in the future.