Cigarette smoking and tooth loss are seldom considered concurrently as determinants of chronic obstructive pulmonary disease (COPD). This study examines the multiplicative effect of self-reported tooth loss and cigarette smoking on COPD among United States adults aged ≥18 years.

Data were taken from the 2012 Behavioral Risk Factor Surveillance System (n = 439,637). Log-linear regression–estimated prevalence ratios (PRs) are reported for the interaction of combinations of tooth loss (0, 1 to 5, 6 to 31, or all) and cigarettes smoking status (never, former, or current) with COPD after adjusting for age, sex, race/ethnicity, marital status, educational attainment, employment, health insurance coverage, dental care utilization, and diabetes.

Overall, 45.7% respondents reported having ≥1 teeth removed from tooth decay or gum disease, 18.9% reported being current cigarette smokers, and 6.3% reported having COPD. Smoking and tooth loss from tooth decay or gum disease were associated with an increased likelihood of COPD. Compared with never smokers with no teeth removed, all combinations of smoking status categories and tooth loss had a higher likelihood of COPD, with adjusted PRs ranging from 1.5 (never smoker with 1 to 5 teeth removed) to 6.5 (current smoker with all teeth removed) (all P <0.05).

Tooth loss status significantly modifies the association between cigarette smoking and COPD. An increased understanding of causal mechanisms linking cigarette smoking, oral health, and COPD, particularly the role of tooth loss, infection, and subsequent inflammation, is essential to reduce the burden of COPD. Health providers should counsel their patients about cigarette smoking, preventive dental care, and COPD risk.