Dual Use of Electronic Cigarettes and Traditional Cigarettes Among Adults: Psychosocial Correlates and Associated Respiratory Symptoms.

Background: Prolonged use of both electronic cigarettes (e-cigarettes) and traditional cigarettes can increase breathing difficulties and other adverse health effects. Research is needed to provide a deeper understanding of predictors of dual use, particularly given rapid changes in the e-cigarette market and related public health communications and policy.

Methods: The sample consists of subjects in the National Longitudinal Study of Adolescent to Adult Health Wave 5 (cross-sectional) subsample ( = 3,800) from 2016 to 2018. Participants were 31-42 y old. Multinomial logistic regression analyses were used to determine predictors of mutually exclusive categories: e-cigarette use only, cigarette use only, and concurrent e-cigarette and traditional cigarette use (compared to no use). Predictors included sex, age, poverty status, race/ethnicity, self-reported diagnosed depression, self-reported diagnosed anxiety, and previous experience of child maltreatment.

Results: Among the total sample ( = 3,800), 2% reported e-cigarette use only, 20% reported traditional cigarette use only, and 3% reported dual use of both e-cigarettes and traditional cigarettes. Among subjects who reported any e-cigarette or traditional cigarette use ( = 957), 12% reported dual use. In the final adjusted multivariable multinomial model, dual use was associated with living at or below the poverty line (odds ratio 2.49 [95% CI 1.19-5.70]), self-reported diagnosed depression (odds ratio 1.99 [95% CI 1.10-3.61]), and a history of child maltreatment (odds ratio 1.80 [95% CI 1.10-2.95]). Additionally, Hispanic-American individuals were more likely to report dual use compared to cigarette-only use.

Conclusions: Prolonged dual use of both e-cigarettes and traditional cigarettes is a considerable public health problem. While our study identified a low percentage of dual usage among U.S. adults, dual use was disproportionately prevalent among those with depression, history of child maltreatment, living at or below the poverty line, and among Hispanic-American individuals. Culturally appropriate interventions and increasing access to cessation programs may help mitigate health disparities pertaining to dual use.