Electronic cigarette use and smoking initiation among youth: a longitudinal cohort study.

BACKGROUND: The influence of e-cigarette use on smoking initiation is a highly controversial issue, with limited longitudinal data available for examining temporal associations. We examined e-cigarette use and its association with cigarette-smoking initiation at 1-year follow-up within a large cohort of Canadian secondary school students. METHODS: We analyzed data from students in grades 9-12 who participated in 2 waves of COMPASS, a cohort study of purposefully sampled secondary schools in Ontario and Alberta, Canada, at baseline (2013/14) and 1-year follow-up (2014/15). We assessed cigarette smoking and e-cigarette use at baseline and follow-up using self-completed surveys. We used generalized linear mixed-effects models to examine correlates of past 30-day e-cigarette use at baseline and smoking initiation between waves within the longitudinal sample. RESULTS: Past 30-day e-cigarette use increased from 2013/14 to 2014/15 (7.2% v. 9.7%, p < 0.001), whereas past 30-day cigarette smoking decreased slightly (11.4% v. 10.8%, p = 0.02). Among the 44 163 students evaluated at baseline, past 30-day e-cigarette use was strongly associated with smoking status and smoking susceptibility. In the longitudinal sample (n = 19 130), past 30-day use of e-cigarettes at baseline was associated with initiation of smoking a whole cigarette (adjusted odds ratio [OR] 2.12, 95% confidence interval [CI] 1.68-2.66) and with initiation of daily smoking (adjusted OR 1.79, 95% CI 1.41-2.28) at follow-up. INTERPRETATION: E-cigarette use was strongly associated with cigarette smoking behaviour, including smoking initiation at follow-up. The causal nature of this association remains unclear, because common factors underlying the use of both e-cigarettes and conventional cigarettes may also account for the temporal order of initiation.

Consumers' Preferences for Electronic Nicotine Delivery System Product Features: A Structured Content Analysis.

To inform potential governmental regulations, we aimed to develop a list of electronic nicotine delivery system (ENDS) product features important to U.S. consumers by age and gender. We employed qualitative data methods. Participants were eligible if they had used an ENDS at least once. Groups were selected by age and gender (young adult group aged 18-25, n = 11; middle-age group aged 26-64, n = 9; and women's group aged 26-64, n = 9). We conducted five individual older adult interviews (aged 68-80). Participants discussed important ENDS features. We conducted a structured content analysis of the group and interview responses. Of 34 participants, 68% were white and 56% were female. Participants mentioned 12 important ENDS features, including: (1) user experience; (2) social acceptability; (3) cost; (4) health risks/benefits; (5) ease of use; (6) flavors; (7) smoking cessation aid; (8) nicotine content; (9) modifiability; (10) ENDS regulation; (11) bridge between tobacco cigarettes; (12) collectability. The most frequently mentioned ENDS feature was modifiability for young adults, user experience for middle-age and older adults, and flavor for the women's group. This study identified multiple features important to ENDS consumers. Groups differed in how they viewed various features by age and gender. These results can inform ongoing regulatory efforts.

Association Between Initial Use of e-Cigarettes and Subsequent Cigarette Smoking Among Adolescents and Young Adults: A Systematic Review and Meta-analysis.

Importance: The public health implications of e-cigarettes depend, in part, on whether e-cigarette use affects the risk of cigarette smoking. Objective: To perform a systematic review and meta-analysis of longitudinal studies that assessed initial use of e-cigarettes and subsequent cigarette smoking. Data Sources: PubMed, EMBASE, Cochrane Library, Web of Science, the 2016 Society for Research on Nicotine and Tobacco 22nd Annual Meeting abstracts, the 2016 Society of Behavioral Medicine 37th Annual Meeting & Scientific Sessions abstracts, and the 2016 National Institutes of Health Tobacco Regulatory Science Program Conference were searched between February 7 and February 17, 2017. The search included indexed terms and text words to capture concepts associated with e-cigarettes and traditional cigarettes in articles published from database inception to the date of the search. Study Selection: Longitudinal studies reporting odds ratios for cigarette smoking initiation associated with ever use of e-cigarettes or past 30-day cigarette smoking associated with past 30-day e-cigarette use. Searches yielded 6959 unique studies, of which 9 met inclusion criteria (comprising 17 389 adolescents and young adults). Data Extraction and Synthesis: Study quality and risk of bias were assessed using the Newcastle-Ottawa Scale and the Risk of Bias in Non-randomized Studies of Interventions tool, respectively. Data and estimates were pooled using random-effects meta-analysis. Main Outcomes and Measures: Among baseline never cigarette smokers, cigarette smoking initiation between baseline and follow-up. Among baseline non-past 30-day cigarette smokers who were past 30-day e-cigarette users, past 30-day cigarette smoking at follow-up. Results: Among 17 389 adolescents and young adults, the ages ranged between 14 and 30 years at baseline, and 56.0% were female. The pooled probabilities of cigarette smoking initiation were 30.4% for baseline ever e-cigarette users and 7.9% for baseline never e-cigarette users. The pooled probabilities of past 30-day cigarette smoking at follow-up were 21.5% for baseline past 30-day e-cigarette users and 4.6% for baseline non-past 30-day e-cigarette users. Adjusting for known demographic, psychosocial, and behavioral risk factors for cigarette smoking, the pooled odds ratio for subsequent cigarette smoking initiation was 3.62 (95% CI, 2.42-5.41) for ever vs never e-cigarette users, and the pooled odds ratio for past 30-day cigarette smoking at follow-up was 4.28 (95% CI, 2.52-7.27) for past 30-day e-cigarette vs non-past 30-day e-cigarette users at baseline. A moderate level of heterogeneity was observed among studies (I2 = 60.1%). Conclusions and Relevance: e-Cigarette use was associated with greater risk for subsequent cigarette smoking initiation and past 30-day cigarette smoking. Strong e-cigarette regulation could potentially curb use among youth and possibly limit the future population-level burden of cigarette smoking.

E-cigs . . . Are They Cool? Talking to Teens About E-Cigarettes.

Electronic cigarettes, or e-cigarettes as they are commonly called, have gained wide acceptance among adolescents, especially those with sweet flavors such as bubble gum and cheesecake. Although health effects of e-cigarettes have not been well characterized, their use increases a teen's exposure to nicotine and may serve as a gateway to traditional cigarettes. This article outlines the basics of e-cigarettes and potential health hazards, followed by selected literature on teens' perceptions of e-cigarettes, as well as motivational interviewing strategies that can be used in talking to teens about using electronic cigarettes.

What factors are associated with current smokers using or stopping e-cigarette use?

BACKGROUND: While some smokers use e-cigarettes and stop smoking, a substantial proportion try e-cigarettes and later discontinue or use them concurrently with smoking (current dual users). The aim was to assess factors associated with ongoing e-cigarette use and discontinuation among smokers. METHODS: Secondary analysis of data of 1489 currently smoking adults, 18 and above, from a GB population-based online survey conducted in March 2016. A multivariable logistic regression assessed motivation to stop smoking among never e-cigarette users, past triers (

Patterns of electronic cigarette use and level of psychological distress.

BACKGROUND: Psychological distress has been correlated with higher levels of nicotine dependence. To date, the possible association between individuals' levels of psychological distress and e-cigarette use has not been investigated, despite the dramatic growth of e-cigarette use in the US. We examined this possible association using a nationally representative sample of US adults. METHODS: A total of 36,697 adults from the 2014 National Health Interview Survey (NHIS) were included. The Kessler 6 scale was used to measure psychological distress. Multivariate logistic regression analysis was conducted to assess the association between level of psychological distress and e-cigarette use. RESULTS: Both e-cigarette and cigarette use varied according to level of psychological distress as well as multiple socio-demographic characteristics. In a multivariate model, psychological distress was significantly associated with the following groups: (a) exclusive e-cigarette ever-use (aOR = 3.7; 95% CI = 1.6, 8.6), (b) current dual use of e-cigarettes and cigarettes (aOR = 4.6; 95% CI = 3.1, 6.7), (c) former cigarette use and ever use of e-cigarette (aOR = 3.2; 95% CI = 2.2, 4.8) and (d) current use of cigarettes only (aOR = 2.1; 95% CI = 1.7, 2.6). CONCLUSION: These are the first data to demonstrate that, as is true for cigarettes, e-cigarette use is associated with increased levels of psychological distress. Further large-scale, longitudinal studies are needed to determine the direction of this relationship and to evaluate the long-term positive and negative consequences of such use.

Lung cancer specialist physicians' attitudes towards e-cigarettes: A nationwide survey.

OBJECTIVES: Despite a sharp increase in e-cigarette use, there is debate about whether e-cigarettes are a viable alternative for harm reduction, and the forms that regulation should take. Healthcare providers can be effective in offering guidance to patients and their families and shaping regulatory policy. We described lung cancer specialists' attitudes toward e-cigarettes and its regulation. METHODS: We undertook a nationwide survey of pulmonologists, thoracic surgeons, medical and radiological oncologists who are members of Korean Association for Lung Cancer. Survey items included beliefs and attitudes toward e-cigarettes, attitudes toward e-cigarette regulation and preparedness on discussing e-cigarettes with their patients. RESULTS: Most respondents believed that e-cigarettes are not safer than conventional tobacco cigarettes (75.7%) or smokeless tobacco (83.2%), and feared that discussing e-cigarettes with the patients would encourage use (65.4%). They did not consider it a smoking cessation treatment (78.3%), and thus would not recommend it to smokers who do not want to quit (82.2%) or who failed to quit with conventional smoking cessation treatment (74.1%). Most respondents supported all examples of e-cigarette regulations, including the safety and quality check (97.8%), warning label (97.8%), advertisement ban (95.1%), restriction of flavoring (78.4%), minimum purchasing age (99.5%), and restriction of indoor use (94.6%). Most learned about e-cigarettes from media and advertisements, or conversation with patients rather than through professional scientific resources, and reported discomfort when discussing e-cigarette with patients. CONCLUSION: Lung cancer specialist physicians in Korea doubt the safety of e-cigarette and use of e-cigarette as smoking cessation treatment, and supported strict regulation. However, only 20% reported that they obtained information on e-cigarettes from the scientific literature and many lacked adequate knowledge based on scientific evidence, suggesting the need for better preparedness. Nevertheless, the views of professionals revealed from our study could help to develop clinical guidelines and regulatory guidance.

The Importance of Conditioned Stimuli in Cigarette and E-Cigarette Craving Reduction by E-Cigarettes.

This study examined the impact of four variables pertaining to the use of e-cigarettes (e-cigs) on cravings for tobacco cigarettes and for e-cigs after an overnight abstinence period. The four variables were the nicotine level, the sensorimotor component, the visual aspect, and the aroma of the e-cig. In an experimental study, 81 participants without prior vaping experience first got acquainted with using e-cigs in a one-week tryout period, after which they participated in a lab session assessing the effect of five minutes of vaping following an abstinence period of 12 h. A mixed-effects model clearly showed the importance of nicotine in craving reduction. However, also non-nicotine factors, in particular the sensorimotor component, were shown to contribute to craving reduction. Handling cues interacted with the level (presence/absence) of nicotine: it was only when the standard hand-to-mouth action cues were omitted that the craving reducing effects of nicotine were observed. Effects of aroma or visual cues were not observed, or weak and difficult to interpret, respectively.

Subjective experiences at first use of cigarette, e-cigarettes, hookah, and cigar products among Texas adolescents.

INTRODUCTION: Subjective experiences ("SEs") at first cigarette use have been thoroughly examined; however, limited research has examined SEs at first use of non-cigarette products. This study addresses this gap in the literature. METHODS: Cross-sectional data from 6th, 8th and 10th grade students in four metropolitan areas of Texas (n=3907/N=461,069). Nausea, coughing, relaxation, rush/buzz, and dizziness at first use were assessed for cigarettes, e-cigarettes, hookah, and cigar products. Chi-square analyses examined differences in the prevalence of first use SEs by product. Weighted multiple logistic regression analyses examined the association of SEs and current product use. Covariates were grade, gender, race/ethnicity, and current other tobacco product use. RESULTS: Exploratory factor analysis of SEs determined differing factor structures across tobacco products. For example, the following items loaded onto the positive SE factor: 1) relaxation, rush, and dizziness for cigarettes, and 2) relaxation and rush for e-cigarettes, hookah, and cigar products. Prevalence of negative SEs (coughing and nausea) were higher for cigarette and cigar products compared to e-cigarettes and hookah. Positive SEs for cigarettes were associated with increased odds of current cigarette use (AOR=1.51); similarly positive SEs for cigars were associated with increased odds of current cigar use (AOR=2.11). Feeling nauseous at first use of cigars was associated with decreased odds of current cigar use (AOR=0.18). No SEs were associated with current e-cigarette or hookah use. CONCLUSIONS: Subjective experiences at first use differ by tobacco product. Longitudinal studies are needed to examine temporal relationships between SEs at first use and sustained tobacco use.

Perceptions of E-Cigarettes among Black Youth in California.

Research suggests that Black youth are less likely to use e-cigarettes than their white counterparts, yet little is known as to why. We examined perceptions of e-cigarettes among Black young adults (ages 18-25) to explore the meanings these youth ascribe to e-cigarettes and the role that identity plays in how these devices are viewed. Analysis of in-depth interviews with 36 Black smokers and non-smokers in the San Francisco Bay Area suggests that Black youth perceive e-cigarettes as serving distinct, yet overlapping roles: a utilitarian function, in that they are recognized as legitimate smoking cessation tools, and a social function, insofar as they serve to mark social identity, specifically a social identity from which our participants disassociated. Participants described e-cigarette users in highly racialized and classed terms and generally expressed disinterest in using e-cigarettes, due in part perhaps to the fact that use of these devices would signal alignment with a middle class, hipster identity. This analysis is discussed within a highly charged political and public health debate about the benefits and harms associated with e-cigarette use.

Adolescent Risk Behaviors and Use of Electronic Vapor Products and Cigarettes.

BACKGROUND: Adolescent use of tobacco in any form is unsafe; yet the use of electronic cigarettes and other electronic vapor products (EVPs) has increased in recent years among this age group. We assessed the prevalence and frequency of cigarette smoking and EVP use among high school students, and associations between health-risk behaviors and both cigarette smoking and EVP use. METHODS: We used 2015 national Youth Risk Behavior Survey data (N = 15 624) to classify students into 4 mutually exclusive categories of smoking and EVP use based on 30-day use: nonuse, cigarette smoking only, EVP use only, and dual use. Prevalence of cigarette smoking and EVP use were assessed overall and by student demographics and frequency of use. Prevalence ratios were calculated to identify associations with health risk-behaviors. RESULTS: In 2015, 73.5% of high school students did not smoke cigarettes or use EVPs, 3.2% smoked cigarettes only, 15.8% used EVPs only, and 7.5% were dual users. Frequency of cigarette smoking and EVP use was greater among dual users than cigarette-only smokers and EVP-only users. Cigarette-only smokers, EVP-only users, and dual users were more likely than nonusers to engage in several injury, violence, and substance use behaviors; have ≥4 lifetime sexual partners; be currently sexually active; and drink soda ≥3 times/day. Only dual users were more likely than nonusers not to use a condom at last sexual intercourse. CONCLUSIONS: EVP use, alone and concurrent with cigarette smoking, is associated with health-risk behaviors among high school students.

A Qualitative Examination of Smoke-Free Policies and Electronic Cigarettes Among Sheltered Homeless Adults.

PURPOSE: To examine attitudes toward smoke-free policies and perceptions of e-cigarette use among homeless adults. APPROACH: A cross-sectional qualitative study was conducted. SETTING: Study setting comprised seven transitional homeless shelters with indoor smoke-free policies in San Diego County; facilities differed in outdoor restrictions on smoking. PARTICIPANTS: Sixty-six current or former smokers were the study participants. METHOD: Participants completed a questionnaire on smoking behaviors, perceived antitobacco norms, and attitudes toward smoke-free policies, and attended a focus group interview that explored these topics. We used a directed content analysis approach to analyze the focus group transcripts. RESULTS: Clients in facilities with outdoor restrictions on smoking had stronger perceived antitobacco norms than those in facilities without such restrictions. We identified the following major themes: attitudes toward smoke-free policies, the use of e-cigarettes, the addictive potential of cigarettes, vulnerability to tobacco industry marketing, and interest in smoking cessation. The consensus was that smoke-free policies were important because they limited secondhand smoke exposure to nonsmokers and children. All were curious about e-cigarettes, particularly if they could be smoked in areas where smoking was prohibited and/or used as a cessation aid. CONCLUSION: In this study of homeless adults, there was strong support for indoor and outdoor smoke-free policies. However, misperceptions that e-cigarettes could be used indoors could threaten antitobacco norms, highlighting opportunities to educate about the potential risks of e-cigarette use among homeless individuals.

Spousal concordance in the use of alternative tobacco products: A multi-country investigation.

BACKGROUND: Married couples often share similar health-related characteristics and behaviors, including cigarette smoking status. Despite their rising popularity in the U.S., little research has examined the patterns of spousal concordance (SC) for alternative tobacco products (ATPs), such as e-cigarettes, cigars, and hookah. METHODS: The purpose of this project was to examine the roles of age, gender, and culture in the strength of SC for these ATPs. Analyses focused on a diverse community sample of married individuals in Ohio, U.S. (N=278), but also examined patterns in Austria, Greece, Israel, the Netherlands, and Slovakia. All participants completed a survey in which they indicated both their own, and their spouse's ever-use of various tobacco products. RESULTS: For the U.S. sample, SC was highest for e-cigarettes, flavored e-cigarettes, flavored cigarettes, and hookah (ϕs=0.48- 0.61); SC appeared to be stronger among younger couples, and when there was only a small female vs. male differences in use. Similar patterns were found in the other countries, with a few key exceptions. In particular, there was low SC for e-cigarettes and flavored e-cigarettes in the other countries, where e-cigarettes had been federally regulated by the time of data collection. CONCLUSION: Overall, these findings have implications for the continued spreading popularity of these tobacco use behaviors.

Knowledge and Beliefs About E-Cigarettes in Straight-to-Work Young Adults.

INTRODUCTION: Young adults are a growing segment of electronic cigarette (e-cigarette) users. Young adults who go straight to work (STW) from high school make up a large portion of the young adult population, yet research to date has focused on college-educated young adults. This study explored STW young adult beliefs and knowledge about e-cigarettes. METHODS: Semistructured individual interviews were used to elicit in-depth information from STW young adults ages 19-31 from a state in the southwest United States. Thirty interviews were conducted focusing on beliefs about e-cigarettes, current knowledge, and information-seeking practices. Interviews were recorded, transcribed, and analyzed using NVivo. RESULTS: Nine themes were identified falling into three categories: (1) beliefs about e-cigarettes, (2) knowledge about e-cigarettes, and (3) personal rules about e-cigarettes. STW young adults held positive beliefs about the health and safety of e-cigarettes for themselves, others, and the environment. They reported their social networks and the Internet as reliable sources of information about e-cigarettes, but they reported parents as the best source for advice. Participants had rules about e-cigarettes that contradicted some of their beliefs such as using e-cigarettes around children indicating that their beliefs were not as strongly held as they initially reported. CONCLUSIONS: Industry marketing and contradictory information may contribute to STW young adult knowledge and beliefs about e-cigarettes. Lack of credible public health information may also contribute to this issue. Ensuring that what is known about the benefits and harms of e-cigarettes is conveyed through multichannel communication and continued monitoring of marketing practices of the e-cigarette industry in light of the soon to be implemented regulations should be top priorities for public health. IMPLICATIONS: Beliefs and knowledge of STW young adults have not been explored even though they are heavily targeted by the e-cigarette industry. This group holds strong positive beliefs about the health and safety of e-cigarettes, despite having little credible knowledge about them. This study indicates a need for efforts focused on educating STW young adults on the potential risks and benefits of e-cigarettes and the communication of credible information or at minimum the acknowledgment of the uncertainty regarding the long-term health effects of e-cigarettes. It also indicates a need for continued monitoring and advocacy related to marketing practices of the e-cigarette industry.

Adolescents' attitudes towards e-cigarette ingredients, safety, addictive properties, social norms, and regulation.

E-cigarette use has dramatically increased. While studies have examined adolescents' attitudes towards smoking, few have extended this research to adolescents' attitudes towards e-cigarettes. The goal of this study was to examine adolescents' attitudes regarding e-cigarette ingredients, safety, addictive properties, social norms, accessibility, price, and regulation; and determine whether attitudes differ by past cigarette/e-cigarette use. Participants were 786 9th and 12th graders from California (63.21% females; mean age=16.10years [SD=1.6]; 26.61% White, 21.98% Asian/Pacific Islander, 29.82% Hispanic, and 21.59% other). Results indicated that 19.05% of participants believed smoke from e-cigarettes is water; 23.03% believed e-cigarettes aren't a tobacco product; 40.36% considered e-cigarettes to be for cessation, and 43.13% felt they were safer than cigarettes. Participants felt it was more acceptable to use e-cigarettes indoors and outdoors compared to cigarettes (p<0.0001), 23.13% felt raising e-cigarette taxes is a bad idea, 63.95% thought e-cigarettes were easier to get than cigarettes, 54.42% felt e-cigarettes cost too much, 64.33% felt the age for buying e-cigarettes should be raised, and 64.37% favored e-cigarette regulation. Adolescents who used e-cigarettes and/or cigarettes had significantly more favorable e-cigarette attitudes than non-users. This study indicates that adolescents are aware of some of the risks of e-cigarettes, although many harbor misperceptions and hold more favorable attitudes towards e-cigarettes than cigarettes. Of concern is the relationship between favorable e-cigarette attitudes and use. Findings suggest the need to provide adolescents with correct information about e-cigarette ingredients, risks, and the insufficient evidence of their role in cigarette cessation.

Motivations and Limitations Associated with Vaping among People with Mental Illness: A Qualitative Analysis of Reddit Discussions.

This study aims to understand the nature and significance of online lay discussions about e-cigarettes and mental illness. We systematically searched the website Reddit.com using keywords related to e-cigarettes and mental illness. We coded relevant posts into themes under the framework of motivations for and limitations of vaping for people with mental illness. The thematic analysis included 3263 comments from 133 discussion threads. Six themes were classified as motivations to vape for people with mental illness: Self-medication; Quitting smoking; Freedom and control; Hobby; Social connectedness; and Motivation from caregivers and online communities. The limitations of vaping included: Unsatisfactory substitute for cigarettes and psychiatric medicines; Drug interactions; Nicotine addiction; Risks of e-liquid; Practical difficulties and Cost. People with mental illness; and their carers; use online discussion boards like Reddit to discuss the benefits and limitations of e-cigarettes for people with mental illness. Both positive and negative views exist. Media platforms like Reddit may shape the opinions of stakeholders and generate lay expertise about contentious health topics such as e-cigarettes. These findings have implications for policy and practice concerning assisting smokers with mental illness to reduce their health risk through switching to e-cigarettes.

Views and Preferences for Nicotine Products as an Alternative to Smoking: A Focus Group Study of People Living with Mental Disorders.

Aims and Background: People living with mental disorders experience a disproportionately higher burden of tobacco-related disease than the general population. Long-term substitution with less harmful nicotine products could reduce the tobacco-related harm among this population. This study investigated the views and preferences of people with mental health disorders about different nicotine products and their use as long-term substitutes for cigarettes. Methods: Semi-structured focus group discussion followed by a brief questionnaire. The discussion transcripts were analysed for content and themes and quantitative data summarised with descriptive statistics. Results: Twenty-nine participants took part in four focus groups. Vaping devices were the most acceptable nicotine products discussed; however preferences for nicotine products were individual and varied along aesthetic, pragmatic, sensory and symbolic dimensions. The concept of tobacco harm reduction was unfamiliar to participants, however they generally agreed with the logic of replacing cigarettes with less harmful nicotine products. Barriers to activating tobacco harm reduction included the symbolism of smoking and quitting; the importance placed on health; the consumer appeal of alternatives; and cost implications. Discussion and Conclusions: Engaging this population in tobacco harm reduction options will require communication that challenges black and white thinking (a conceptual framework in which smoking cigarettes or quitting all nicotine are the only legitimate options) as in practice this serves to support the continuance of smoking. Consumers should be encouraged to trial a range of nicotine products to find the most acceptable alternative to smoking that reduces health harms. Providing incentives to switch to nicotine products could help overcome barriers to using less harmful nicotine products among mental health consumers.

Changes in Electronic Cigarette Use from 2013 to 2015 and Reasons for Use among Finnish Adolescents.

Electronic cigarettes are quite a new potential source of nicotine addiction among youth. More research is needed, particularly on e-liquid use and socioeconomic factors as potential determinants. We studied changes from 2013 to 2015 in adolescent e-cigarette awareness and ever-use, types of e-liquids, and determinants in Finland. In 2015, we studied weekly use and reasons for ever-use. Data were from two national surveys of 12-18-year-old Finns (2013, n = 3535, response rate 38%; 2015, n = 6698, 41%). Descriptive statistics and logistic regression analysis were used. Awareness and ever-use of e-cigarettes increased significantly from 2013 to 2015 in all age and gender groups. Ever-use increased from 17.4% to 25%, with half having tried nicotine e-liquids. In 2015, weekly use was rare (1.5%). Daily cigarette smoking was the strongest determinant (OR 51.75; 95% CI 38.18-70.14) for e-cigarette ever-use, as for e-cigarette weekly use, but smoking experimentation and ever-use of snus (Swedish type moist snuff) and waterpipes alongside parental smoking and poor academic achievement also increased the odds for ever-use. The most common reason behind e-cigarette ever-use was the desire to try something new. To conclude, adolescent e-cigarette ever-use is increasing, and also among never-smokers. Tobacco-related factors are stronger determinants for e-cigarette use than socioeconomic factors.

How is the effect of adolescent e-cigarette use on smoking onset mediated: A longitudinal analysis.

E-cigarette use by adolescents has been related to onset of cigarette smoking but there is little knowledge about the process(es) through which this occurs. Accordingly, we tested the role of cognitive and social factors for mediating the relation between e-cigarette use and smoking onset. A school-based survey was conducted with a baseline sample of 2,338 students in Hawaii (9th and 10th graders, mean age 14.7 years) who were surveyed in 2013 (Time 1, T1) and followed up 1 year later (Time 2, T2). We assessed e-cigarette use, cigarette smoking, demographic covariates, and 4 hypothesized mediators: smoking-related expectancies, prototypes, and peer affiliations as well as marijuana use. The primary structural modeling analysis, based on initial never-smokers, used an autoregressive model (entering T2 mediator values adjusted for T1 values) to test for mediational pathways in the relation between e-cigarette use at T1 and cigarette smoking status at T2. Results showed that e-cigarette use was related to all of the mediators. Tests of indirect effects indicated that changes in expectancies, affiliations, and marijuana use were significant pathways in the relation between e-cigarette use and smoking onset. A direct effect from e-cigarette use to smoking onset was nonsignificant. Findings were replicated across autoregressive and prospective models. We conclude that the relation between adolescent e-cigarette use and smoking onset is in part attributable to cognitive and social processes that follow from e-cigarette use. Further research is needed to understand the relative role of nicotine and psychosocial factors in smoking onset. (PsycINFO Database Record

Effects of sweet flavorings and nicotine on the appeal and sensory properties of e-cigarettes among young adult vapers: Application of a novel methodology.

INTRODUCTION: Product characteristics that impact e-cigarette appeal by altering the sensory experience of vaping need to be identified to formulate evidence-based regulatory policies. While products that contain sweet flavorings and produce a "throat hit" (i.e., desirable airway irritation putatively caused by nicotine) are anecdotally cited as desirable reasons for vaping among young adults, experimental evidence of their impact on user appeal is lacking. This experiment applied a novel laboratory protocol to assess whether: (1) sweet flavorings and nicotine affect e-cigarette appeal; (2) sweet flavorings increase perceived sweetness; (3) nicotine increases throat hit; and (4) perceived sweetness and throat hit are associated with appeal. METHODS: Young adult vapers (N=20; age 19-34) self-administered 20 standardized doses of aerosolized e-cigarette solutions varied according to a 3 flavor (sweet [e.g., cotton candy] vs. non-sweet [e.g., tobacco-flavored] vs. flavorless)×2 nicotine (6mg/mL nicotine vs. 0mg/mL [placebo]) double-blind, cross-over design. Participants rated appeal (liking, willingness to use again and perceived monetary value), perceived sweetness and throat hit strength after each administration. RESULTS: Sweet-flavored (vs. non-sweet and flavorless) solutions produced greater appeal and perceived sweetness ratings. Nicotine produced greater throat hit ratings than placebo, but did not significantly increase appeal nor interact with flavor effects on appeal. Controlling for flavor and nicotine, perceived sweetness was positively associated with appeal ratings; throat hit was not positively associated with appeal. CONCLUSIONS: Further identification of compounds in e-cigarette solutions that enhance sensory perceptions of sweetness, appeal, and utilization of e-cigarettes are warranted to inform evidence-based regulatory policies.