Fei Liu

Bio: Fei Liu is an academic researcher from University of Southern California. The author has contributed to research in topics: Tobacco control & Cigarillo. The author has an hindex of 5, co-authored 7 publications receiving 72 citations.

Tobacco Marketing and Subsequent Use of Cigarettes, E-Cigarettes, and Hookah in Adolescents

Abstract: Introduction Tobacco marketing has expanded from cigarettes to other tobacco products through many promotional channels. Marketing exposure is associated with use of that tobacco product. However, it is unclear if marketing for one product leads to subsequent use of other tobacco products. Methods This prospective cohort study assessed self-reported marketing exposure for six tobacco products across five marketing channels in 11th and 12th grade students in 2014. Approximately 16 months later, a follow-up survey was conducted online (N = 1553) to assess initiation of cigarettes, electronic cigarettes (e-cigarettes), and hookah. Results Adolescent never-smokers with frequent exposure to cigarette marketing on the Internet and in stores are more than two times as likely to begin smoking as young adults (Internet OR = 2.98 [95% CI = 1.56 to 5.66]; stores OR = 2.83 [95% CI = 1.23 to 6.50]). Never users of e-cigarettes were significantly more likely to initiate use, if exposed to Internet, store, and outdoor e-cigarette marketing. Never users of hookah were more likely to use hookah after seeing it marketed in stores. Youth exposed to marketing of e-cigarettes, hookah, cigars, smokeless tobacco, and pipe tobacco in stores were two to three times more likely to begin smoking cigarettes even though the marketed products were not cigarettes. Conclusions Adolescent exposure to marketing of tobacco products is associated with initiation of those products as young adults. Exposure to marketing for non-cigarette tobacco products is associated with subsequent cigarette smoking, even when the promoted products are not cigarettes. Future research and interventions should consider the influence of marketing from multiple tobacco products on adolescent tobacco use. Implications Adolescents grow up in a rich media environment with exposure to tobacco marketing in both their homes (eg, through the Internet and television) and their communities (eg, stores and billboards). This prospective study provides evidence that adolescents exposed to tobacco marketing for multiple tobacco products are more likely to subsequently begin using those products and to begin smoking cigarettes even when the marketing they recall is for different tobacco products. Adolescent exposure to tobacco marketing can increase likelihood of cigarette smoking, e-cigarette, and hookah use with potential lifelong health effects.

E-cigarette and cigarette purchasing among young adults before and after implementation of California's tobacco 21 policy.

Abstract: Background Tobacco 21 (T21) laws, which raise the minimum legal age of sale of tobacco products to 21, have been proposed and implemented in states and cities across the USA. However, limited data are available on the effect of T21 laws on youth tobacco purchasing behaviours and access to tobacco products. Methods Participants in a population-based prospective cohort in southern California completed questionnaires before (n=1609, age=18–19 y) and after (n=1502, age=19–20 y) T21 was implemented in California (June 2016). We examined the prevalence of past 30-day cigarette and e-cigarette use, and among past 30-day users, purchase location of tobacco products before (pre-) versus after (post-) T21. We also examined whether, post-T21, participants were refused purchase of tobacco products due to their age, and the perceived relative ease of purchasing cigarettes and e-cigarettes (vs pre-T21). Results Negligible changes in cigarette and e-cigarette use were observed pre-T21 versus post-T21. At both time points, the majority of past 30-day users purchased cigarettes from gas stations and e-cigarettes from vape shops. Post-T21, the proportion of participants who reported purchasing cigarettes at gas stations decreased. Post-T21, most past 30-day cigarette or e-cigarette users were not refused purchase of cigarettes (65.4%) or e-cigarettes (82.0%) in the past 30 days, despite being under 21; half of the participants felt it was harder to purchase cigarettes (54.3%) and e-cigarettes (43.6%) post-T21. Conclusion Post-T21, few participants were refused purchase of any tobacco product, despite the illegality of such sales. Better enforcement of T21 is needed to improve the efficacy of T21 legislation.

E-cigarette Use and Subsequent Smoking Frequency Among Adolescents

Abstract: BACKGROUND AND OBJECTIVES: Electronic cigarette (e-cigarette) use is associated with cigarette initiation among adolescents. However, it is unclear whether e-cigarette use is associated with more frequent cigarette use after initiation. Also, the extent to which cigarette or dual cigarette and e-cigarette users transition to exclusive e-cigarette use or to the nonuse of either product is not yet known. METHODS: Data were pooled from 3 prospective cohort studies in California and Connecticut (baseline: 2013–2014; follow-up: 2014–2016; N = 6258). Polytomous regression models were used to evaluate the association of baseline e-cigarette use (never or ever) with cigarette use frequency at follow-up (experimental: initiation but no past-30-day use; infrequent: 1–2 of the past 30 days; frequent: 3–5 or more of the past 30 days). Polytomous regression models were also used to evaluate transitions between baseline ever or past-30-day single or dual product use and past-30-day single or dual product use at follow-up. RESULTS: Among baseline never smokers, e-cigarette users had greater odds of subsequent experimental (odds ratio [OR] = 4.58; 95% confidence interval [CI]: 3.56–5.88), infrequent (OR = 4.27; 95% CI: 2.75–6.62) or frequent (OR = 3.51; 95% CI: 1.97–6.24) cigarette use; the 3 OR estimates were not significantly different. Baseline past-30-day exclusive cigarette use was associated with higher odds at follow-up of exclusive cigarette or dual product use than of exclusive e-cigarette use. CONCLUSIONS: Tobacco control policy to reduce adolescent use of both e-cigarettes and cigarettes is needed to prevent progression to more frequent tobacco use patterns and reduce combustible cigarette use (with or without concurrent e-cigarette use) to lessen the adverse public health impact of e-cigarettes.

A Review of the Use and Appeal of Flavored Electronic Cigarettes

Abstract: E-cigarettes are available in a variety of flavors not found in traditional tobacco products (i.e., “nontraditional flavors”), which is a commonly cited reason for e-cigarette use. This review examines the prevalence of nontraditional-flavored e-cigarette use, mechanisms through which flavorings enhance product appeal, use of nontraditional-flavored e-cigarettes for smoking cessation, and differences in these findings between youth and adults. Nontraditional-flavored e-cigarettes are used at e-cigarette initiation by the majority of youth. These flavors enhance the appeal of e-cigarettes by creating sensory perceptions of sweetness and coolness and masking the aversive taste of nicotine. Use of nontraditional-flavored e-cigarettes is higher among youth and young adults (vs. older adults) and among nonsmokers (vs. combustible cigarette smokers). Nontraditional-flavored e-cigarettes are popular among youth, but may be less common among older adults and combustible cigarette smokers. Further research is needed to determine whether use of e-cigarettes in nontraditional flavors affects smoking cessation.

Race, Educational Attainment, and E-Cigarette Use

Abstract: Background: Although higher educational attainment lowers high-risk behaviors such as substance use, according to the Minorities’ Diminished Returns theory, the effect of educational attainment may be smaller for Blacks than Whites. Aims: To explore the racial differences in the link between educational attainment and electronic cigarettes (e-cigarettes). Methods: We used the Health Information National Trends Survey (HINTS) data. This national survey was conducted in 2017 and included 2,277 American adults composed of 1,868 White and 409 Black individuals. Educational attainment was the independent variable. E-cigarette use (lifetime) was the dependent variables. Age and gender were the covariates. Race was the effect modifier. Results: In the overall sample, a higher level of education attainment was linked to lower odds of e-cigarette use (OR = 0.76, 95% CI =0.61-0.95). Race showed a significant interaction with educational attainment on the outcome (OR = 1.63, 95% CI =1.04-2.56), suggesting a weaker negative association between high educational attainment and e-cigarette use for Blacks than Whites. In race-stratified logistic regression models, high educational attainment was inversely associated with risk of e-cigarette use for Whites but not Blacks. Conclusion: Educational attainment shows a stronger effect on e-cigarette use in White than Black Americans.

Predictive Validity of the Expanded Susceptibility to Smoke Index - eScholarship

Abstract: Objectives:The susceptibility to smoking index can be improved as it only identifies one third of future adult smokers. Adding curiosity to this index may increase the identification of future smokers and improve the identification of effective prevention messages.Methods:Analyses used data from the California Longitudinal Study of Smoking Transitions in Youth, for whom tobacco use behaviors, attitudes, and beliefs were assessed at 3 time points from age 12 through early adulthood. Logistic regressions were used to evaluate whether baseline curiosity about smoking was predictive of smoking during the 6-year follow-up period and whether curiosity about smoking provided evidence of incremental validity over existing measures of susceptibility to smoking.Results:Compared to those who were classified as definitely not curious about smoking, teens who were classified as probably not curious (ORadj = 1.90, 95% CI = 1.28–2.81) and those classified as definitely curious (ORadj = 2.38, 95% CI= 1.49–3.79) had an increase in the odds of becoming a young adult smoker. Adding curiosity to the original susceptibility to smoking index increased the sensitivity of the enhanced susceptibility index to 78.9% compared to 62.2% identified by the original susceptibility index. However, a loss of specificity meant there was no improvement in the positive predictive value.Conclusions:The enhanced susceptibility index significantly improves identification of teens at risk for becoming young adult smokers. Thus, this enhanced index is preferred for identifying and testing potentially effective prevention messages.