Childhood Cigarette Smoking and Risk of Chronic Obstructive Pulmonary Disease in Older U.S. Adults
James D. Sargent, Michael J. Halenar, Alexander W. Steinberg, Jenny E. Ozga, Zhiqun Tang, Cassandra A. Stanton, Laura M. Paulin
Abstract
Abstract Rationale It is not certain the extent to which childhood smoking adds chronic obstructive pulmonary disease (COPD) risk independent of lifetime cigarette exposure. Objectives We examined the association between age started smoking cigarettes regularly, current smoking status, smoking history, and risk of COPD. Methods Cross-sectional survey of U.S. adults ≥40 years old in the 2020 National Health Interview Survey. Respondents who were ever cigarette smokers were asked when they began smoking regularly. Multivariable analysis assessed self-report of COPD diagnosis as a function of age started smoking (<15 yr vs. ≥15 yr) adjusting for current smoking, cigarette pack-years, and covariates. Measurements and Main Results Overall, 7.1% reported that they had COPD, 2.6% for never-smokers compared with 23.1% and 11.6% for smoking onset <15 and ≥15 years, respectively. Persons who began smoking regularly at <15 years of age had higher pack-years of smoking (median, 29 vs. 15, respectively), and higher smoking intensity (median, 20 cigarettes/d for <15 yr vs. 10 cigarettes/d for ≥15 yr for current smokers). In the multivariable analysis, the relative risk for COPD among childhood smokers was 1.41 (95% confidence interval, 1.22–1.63) compared with later-onset smokers. Substituting smoking duration for pack-years confounded the association between current smoking and COPD but did not change the childhood smoking estimate. In a stratified analysis, higher risk for childhood smoking was found at all current smoking intensity levels. Conclusions Among adults aged ≥40 years, one-fifth of childhood smokers have COPD. Lifetime cigarette smoking explained some but not all of the higher risk. If replicated, this suggests a lung development window of enhanced vulnerability to cigarette smoking.