Background: The objective of this study was to examine the relationship between airway obstruction and periodontal disease.Methods: Participants were a subset of 860 community-dwelling, well functioning elderly (aged 70 to 79, blacks and whites, males and females) selected from 2,732 participants enrolled in the Health, Aging, and Body Composition Study (Health ABC). The periodontal evaluations occurred over years 2 and 3 of the study and included four indices of periodontal health: plaque index (PI), gingival index (GI), probing depth (PD), and loss of attachment (LOA). The pulmonary evaluation took place in year 1: conducted according to American Thoracic Society criteria, based on the forced expiratory volume/forced vital capacity (FEV1/FVC) ratio and then using the percent of predicted FEV1 to categorize severity.Results: GI (P= 0.023) and LOA (P= 0.009) were significantly better in participants with normal pulmonary function compared to those with airway obstruction after adjusting for age, race, gender, and field center. When stratified by smoking status and after adjusting for age, race, gender, center, and pack-years, there was a significant association between periodontal health and airway obstruction in former smokers. Within this group, those with normal pulmonary function had significantly better GI (P= 0.036) and LOA (P= 0.0003) scores than those with airway obstruction. All periodontal indices were elevated in smokers regardless of pulmonary status; however, the current smoker group was too small to detect a periodontitis effect.Conclusion: While the present cross-sectional study cannot provide direct inference of cause and effect, it does reveal a significant association between periodontal disease and airway obstruction, particularly informer smokers.