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A4451 - Prospective Follow-Up of Respiratory Symptoms Among Young Adults with a History of Electronic Cigarette Use
Author Block: R. Urman1, J. Barrington-Trimis1, F. Liu1, H. Hong2, K. Berhane1, A. Leventhal1, R. McConnell1; 1University of Southern California, Los Angeles, CA, United States, 2Pulmonology, Children's Hospital Los Angeles, Los Angeles, CA, United States.
RATIONALE: Use of electronic (e-) cigarettes has increased rapidly worldwide since their introduction into the market. In the United States, approximately 11% of high school students in 2016 reported using e-cigarettes in the past 30-days. Components of e-cigarette aerosol have known pulmonary toxicity, resulting in oxidative stress and inflammatory effects, and decreased cell viability. Yet, there has been little study of the chronic effects of e-cigarette use on respiratory health. We investigated prospectively the association of e-cigarette use with chronic respiratory symptoms in young adults.
METHODS: Ever and current use of e-cigarettes and cigarettes by 1470 Southern California Children’s Health Study participants was assessed in a self-completed baseline questionnaire in 11th and 12th grade in 2014 and in two follow-up waves in 2015-2016 and in 2017. Respiratory symptoms assessed at the last follow-up in 2017 included chronic bronchitic symptoms (chronic cough, phlegm or bronchitis), or wheeze, in the past 12 months, and shortness of breath when walking on level ground or slightly uphill. The associations of use of e-cigarettes, characterized based on when use was first initiated and on current (past 30-day) use in repeated waves of follow-up, with respiratory symptoms were assessed in prospective analyses using logistic regression models.
RESULTS: Baseline e-cigarette use was reported by 22% of participants. In models adjusted for sociodemographic characteristics, baseline secondhand smoke exposure, and lifetime number of cigarettes smoked, we found ever use of e-cigarettes at baseline to be associated with an increased risk of chronic bronchitic symptoms during last follow-up in 2017 (OR: 1.51; 95% CI: 1.03, 2.21). Participants who initiated e-cigarette use between baseline and the first follow-up visit were also at increased risk of reporting chronic bronchitis (OR: 1.71; 95% CI: 1.20, 2.44) as well as wheeze (OR: 1.95; 95% CI: 1.28, 2.99). Compared to never users of e-cigarettes, participants who indicated being a current user of e-cigarettes at baseline and both follow-up waves were at greater risk of reporting wheeze (OR: 3.18; 95% CI: 1.18, 8.53) and shortness of breath (OR: 3.57; 95% CI: 1.37, 9.30) but not chronic bronchitic symptoms (OR: 1.08, 95% CI: 0.40, 2.94).
CONCLUSIONS: The prospective association of adolescent e-cigarette use with respiratory symptoms, independent of cigarette use, is consistent with emerging evidence from toxicological and epidemiological studies that e-cigarette use adversely affects lung health.