Ever Use of Nicotine and Nonnicotine Electronic Cigarettes Among High School Students in Ontario, Canada

Youth Demographic Characteristics and Risk Perception of Using Alternative Tobacco Products: An Analysis of the 2014-2015 Canadian Student Tobacco, Alcohol, and Drugs Survey (CSTADS)

Background

There is a growing attraction by youth to alternative tobacco products (ATPs) such as e-cigarettes and hookahs. This study investigated risk perceptions and demographic characteristics associated with ATP use in grade 8-10 students.

Methods

Data were drawn from the 2014/15 cycle of the CSTADS. The analytic sample included 1819 students from a total pool of 42 094 students who completed the survey. Logistic regression models were used to examine factors (demographic characteristics and risk perception) associated with ATP use in the past 30 days.

Results

12% of students in grade 8-10 self-identified as having used ATPs in the past 30-days, with a majority of students in grade 10 (56%). Male students had higher odds of reporting ATP use when compared to females. Although a lesser proportion of Indigenous students reported ATP use in comparison to White students (31% vs 61%), Indigenous students were 2.42 (1.49, 3.93) times as likely to use ATPs as White students. Students who perceived smoking hookah once in a while as "no to slight risk" were 1.58 (1.09, 2.28) times more likely to report ATP use than students who perceived "moderate to great risk." Also, students who perceived using e-cigarettes on a regular basis as "no to slight risk" were 2.21 (1.53, 3.21) times more likely to report ATP use as students who perceived "moderate-great risk."

Conclusion

A significant number of grade 8-10 students use ATPs, especially e-cigarettes, with the misconception of minimal health risks. There remains the need to do more to counteract the rise in social and epidemiological alternative tobacco use trends among the youth.

Correlates of Lifetime and Past Month Vape Use in a Sample of Canadian University Students

Introduction

This study examines correlates of lifetime (ie, ever vaped) and past month vape use among students aged 17 to 19 years, 20 to 25 years, and 26+ years from Western University in London, Ontario. The secondary objective is to assess lifetime and past month vape use among students not of legal age to purchase vaping products in Ontario (ie, those 17 to 18 years only).

Methods

Using Qualtrics, a cross-sectional survey was sent via email to all students at Western University (N = 38 442), assessing their current and past risk-taking behaviors, mental health, sociodemographic characteristics, as well as questions pertaining to their family structure and socioeconomic background during childhood. Students were asked if they had ever vaped in their lifetime and about past month vape use. Logistic regression models were used to assess correlates of lifetime and past month vape use.

Results

The sample consisted of 2626 university students. Compared to those ages 26+ years, teenage university students were 10 times more likely to have vaped in the past month and males were twice as likely as females to have vaped. Alcohol use doubled the odds of vaping in the past month, whereas cigarette, cannabis, or cocaine use approximately tripled the odds. Students who reported many sexual partners were far more likely to have vaped in the past month.

Conclusion

Vape use is more common among teenage university students, males, those who drink alcohol, smoke, use cannabis or cocaine, and who report many sexual partners.

Advances in Smoking Related In Vitro Inhalation Toxicology: A Perspective Case of Challenges and Opportunities from Progresses in Lung-on-Chip Technologies

The inhalation toxicology of multifaceted particulate matter from the environment, cigarette smoke, and e-cigarette liquid vapes is a major research topic concerning the adverse effect of these items on lung tissue. In vitro air-liquid interface (ALI) culture models hold more potential in an inhalation toxicity assessment. Apropos to e-cigarette toxicity, the multiflavor components of the vapes pose a complex experimental bottleneck. While an appropriate ALI setup has been one part of the focus to overcome this, parallel attention towards the development of an ideal exposure system has pushed the field forward. With the advent of microfluidic devices, lung-on-chip (LOC) technologies show enormous opportunities in in vitro smoke-related inhalation toxicity. In this review, we provide a framework, establish a paradigm about smoke-related inhalation toxicity testing in vitro, and give a brief overview of breathing LOC experimental design concepts. The capabilities with optimized bioengineering approaches and microfluidics and their fundamental pros and cons are presented with specific case studies. The LOC model can imitate the structural, functional, and mechanical properties of human alveolar-capillary interface and are more reliable than conventional in vitro models. Finally, we outline current perspective challenges as well as opportunities of future development to smoking lungs-on-chip technologies based on advances in soft robotics, machine learning, and bioengineering.

Factors associated with electronic cigarettes use among adolescents in Jakarta, Indonesia

Purpose

This study aimed to examine factors associated with electronic cigarette use among adolescents aged 15–19 in Jakarta, Indonesia.

Design/methodology/approach

The study was a school-based survey involving 1,318 students from 14 high schools in Jakarta. A multistage cluster sampling methodology was used. The authors used the chi-square test and multiple logistic regression to examine the association between electronic cigarette use and sociodemographic, social influences, health risk perceptions, availability, affordability and conventional cigarette smoking status.

Findings

Overall, 6.3% of females and 29% of males reported ever having used electronic cigarettes. Electronic cigarette use was independently associated with sex, school locations, conventional cigarette smoking status, peer use, availability and perceptions that electronic cigarettes aid conventional cigarette smoking cessation. Compared with non-smokers, lifetime (AOR: 8.740, 95% CI: 5.126–14.901) and current conventional cigarette smokers (AOR: 18.380, 95% CI: 10.577–31.938) were more likely to use electronic cigarettes.

Social implications

The use of electronic cigarettes among adolescents was considerably high in this study. Therefore, the tobacco control policy should be extended to regulate the marketing and use of all types of tobacco products and not just conventional cigarettes.

Originality/value

The study explored beyond individual lifestyle factors that contributed to electronic cigarette use in Indonesia such as affordability, school locations and availability of electronic cigarettes. These issues have not been specifically discussed in previous studies.

E-cigarettes: A new hazard for children and adolescents

Objectives

Electronic cigarettes and fluid (e-cigarettes, e-fluid) are hazardous materials that when inhaled or ingested may pose significant health risks to children and adolescents. The objective of this work was to explore the spectrum of injury related to e-cigarette exposure among Canadian children and adolescents.

Methods

A one-time survey was sent to all paediatricians in Canada. Information was collected on children and adolescents who presented with e-cigarette exposure (inhalation and ingestion cases) in the previous 12 months. Questions included the number of injuries and symptoms, in addition to age, sex, treatment setting, intentional e-cigarette use, and how the products were accessed.

Results

A total of 520 surveys were completed and returned, identifying 35 cases. Symptoms related to inhalation were present in 30 cases and in 5 ingestion cases (5 unintentional, 0 intentional). For inhalation cases, most were male, ages 15 to 19 years, who sought treatment for nausea/vomiting, cough, throat irritation, or acute nicotine toxicity in an outpatient clinic/office. Most inhalation cases reported e-cigarette use 2 to 3 days/week, and e-cigarettes purchases from a mall kiosk/store. For ingestion cases, most were male, ages 1 to 4 years presenting to an emergency department with nausea/vomiting, cough, or respiratory irritation. Younger cases accessed e-fluid at home, older cases purchased in a mall kiosk/store. E-fluid flavours reported consumed were fruit, candy, and tobacco.

Conclusions

E-cigarettes, recently introduced into the North American market are hazardous to children and adolescents. Given the low response rate to the survey, further investigation into the true burden of injury, as well as the risks that e-cigarettes pose, together with ways to reduce exposure, is needed.

World vaping update

PURPOSE OF REVIEW

Although death and injury related to e-cigarette use and vaping products has decreased since the peak in 2019, concern over the popularity of electronic nicotine delivery systems (ENDS - a term which includes vape pens, electronic or e-cigarettes, and products that produce vapor for inhaling rather than combusting to produce smoke) continues. ENDS are used as an aid to quit smoking and for harm reduction.

RECENT FINDINGS

This review covers peer-reviewed literature from January 2019 through February 2020 on vaping (the process of using ENDS). Prevalence, risk factors for use, and health risks and benefits from use predominated. Policy articles, commentaries and editorials were excluded from review. E-cigarette or vaping product use-associated lung injury (EVALI)-related injury and death were in the news and literature this year. Because most EVALI-related injury and death occurred among young people who had vaped tetrahydrocannabinol (THC), data from the Healthy Minds (United States) study are reviewed to consider variation in risk factors for vaping THC compared with nicotine.

SUMMARY

Findings provide up-to-date information on vaping as a way to consume a drug, whether THC or nicotine. Harm reduction benefits were shown in a year-long follow-up of smoking cessation; harms continue to accumulate, including from passive consumption.

Heat-not-burn tobacco, electronic cigarettes, and combustible cigarette use among Japanese adolescents: a nationwide population survey 2017

BACKGROUND

From among the global public health concerns, smoking remains one of the most crucial challenges. Especially for adolescents, the increase in the use of electronic cigarettes is controversial, as its use may lead to established smoking. In Japan, where a unique tobacco regulation system exists, the heat-not-burn tobacco market has been growing. However, the prevalence and association of combustible cigarettes and new tobacco-related products have not yet been closely investigated among Japanese adolescents. This study aimed to clarify the prevalence of smoking among adolescents, including new types of tobacco-related products, and to compare the characteristics of their users.

METHODS

The 2017 Lifestyle Survey of Adolescents is a nationally-representative survey collected in Japan. From the national school directory, 98 junior high schools and 86 high schools were randomly sampled throughout Japan. The students completed an anonymous questionnaire at school. We calculated the prevalence of use for each type of tobacco product. Then, the use of a combination of products and the characteristics of different types of products were examined.

RESULTS

In total, 64,152 students from 48 junior high schools and 55 high schools were included the analysis (school response rate = 56%, Mage = 15.7 years, 53.9% boys). The age-adjusted rate of ever (current) use of electronic cigarettes was 2.1% (0.7%) in junior high school and 3.5% (1.0%) in high school; that of combustible cigarettes was 2.6% (0.6%) in junior high school and 5.1% (1.5%) in high school. The rate of heat-not-burn tobacco use was lower relative to other products: 1.1% (0.5%) in junior high school and 2.2% (0.9%) in high school. An examination of the combined use of the three products identified a high number of dual users. Comparisons between different types of users indicated different backgrounds for combustible cigarette users and new product users.

CONCLUSIONS

The prevalence of new tobacco-alternative products is growing in popularity among Japanese adolescents. Dual use is common, and many adolescents use new products only. Moreover, e-cigarettes might attract a broader range of groups to smoking. Continuous monitoring and research are needed to investigate their influence as a possible gateway to tobacco smoking.

Nicotine and marijuana attitudes among flavor-only vaping youth: New evidence from Monitoring the Future

BACKGROUND

Vaping has become increasingly popular among youth and young adults in the last decade. At present, very little research has examined how vaping is associated with attitudes concerning the disapproval and perceived risk of using other substances. This paper examines the association between flavor-only vaping and attitudes concerning nicotine and marijuana use in a sample of high school students with no history of nicotine or marijuana use.

METHODS

We employed negative binomial regression and logistic regression techniques to examine the associations between flavor-only vaping activity and attitudes concerning the risk and disapproval of nicotine and marijuana use utilizing data from the 2017 cohort of Monitoring the Future (MTF).

RESULTS

The results suggest that, net of covariates, flavor-only vaping is not significantly associated with attitudes concerning traditional forms of nicotine use. However, flavor-only vaping does appear to be positively and significantly associated with the failure to disapprove and/or perceive the risk of vaping nicotine and regular marijuana use.

CONCLUSIONS

Flavor-only vaping is positively and significantly associated with the failure to disapprove and/or perceive the risk of vaping nicotine and regular marijuana use.

Sex Differences in Becoming a Current Electronic Cigarette User, Current Smoker and Current Dual User of Both Products: A Longitudinal Study among Mexican Adolescents

This study aimed to assess sex differences in predictors for becoming a current exclusive electronic cigarette (e-cigarette) user, current exclusive smoker, or current dual user (concurrent smoking and e-cigarette use). This longitudinal study included 2399 females and 2177 males who had tried neither cigarettes nor e-cigarettes at baseline and attended 57 middle schools in the three largest cities in Mexico. We estimated multinomial logistic models stratified by sex. At follow-up, the prevalence of current exclusive e-cigarette use was 6.4% for males and 5.5% for females; current exclusive smoking was similar among males (3.6%) and females (3.5%); dual use was 2.4% females and 1.8% males. In the adjusted model, current e-cigarette use among females was associated with baseline current drinking (ARR = 1.85; p < 0.05), having a job (ARR = 1.99; p < 0.05), higher technophilia (ARR = 1.27; p < 0.05), and higher positive smoking expectancies (ARR = 1.39; p < 0.05). Among males, only having friends who smoke cigarettes at baseline was a significant predictor of current exclusive e-cigarette use at follow-up (ARR = 1.44; p < 0.05). For both sexes, current exclusive smoking at follow-up was associated with baseline current drinking (male ARR = 2.56; p < 0.05; female ARR = 2.31; p < 0.05) and, among males, only with having a parent who smoked (ARR = 1.64; p < 0.05). For both sexes, dual use at follow-up was associated with baseline current drinking (male ARR = 3.52; p < 0.005; female ARR = 2.77; p < 0.05); among females, with having paid work (ARR = 2.50; p < 0.001); and among males, with parental smoking (ARR = 3.20; p < 0.05). Results suggested both common and different risk factors by sex, suggesting that interventions may need to consider targeting sex differences.

The Prevalence of Vaping and Smoking as Modes of Delivery for Nicotine and Cannabis among Youth in Canada, England and the United States

Background: Vaping has become an increasingly common mode of administration for both nicotine and cannabis, with overlap among users, devices, as well as nicotine and cannabis companies. There is a need to understand patterns of use among youth, including the way nicotine and cannabis are administered. Methods: Data are from Wave 2 of the ITC Youth Tobacco and Vaping survey, an online survey conducted in 2018 among 16-19 year-olds recruited from commercial panels in Canada (n = 3757), England (n = 3819), and the U.S. (n = 3961). The prevalence of past 30-day vaping nicotine, non-nicotine and cannabis substances, as well as cannabis modes of use was examined. Logistic regression models examined between country differences in prevalence. Results: Past 30-day cannabis use was highest among Canadian youth (16.6%), followed by youth in the U.S. (13.8%) and England (9.0%). Vaping e-cigarettes was substantially more prevalent than vaping cannabis in all three countries. All forms of cannabis use were higher among Canadian and U.S. youth compared to England (p < 0.001 for all). Past 30-day cannabis users in the U.S. were more likely to report vaping cannabis oil (30.1%), and consuming solid concentrates such as wax and shatter (30.2%), compared to cannabis users in Canada (18.6% and 22.9%) and England (14.3% and 11.0%; p < 0.001 for all). Conclusions: Youth are administering cannabis and nicotine using a wide diversity of modes. Cannabis users in the U.S.-where an increasing number of states have legalized medical and non-medical cannabis-reported notably higher use of more potent cannabis products, including cannabis oils and extracts.

Electronic Cigarette Burns: A Case Report and Review of Current Literature

Due to the development of electronic cigarettes and their use in our patient population, this article seeks to evaluate the safety and associated morbidity that may result from their use. This article also presents a patient case regarding an explosion of an electronic cigarette battery and the resultant injury and deformity that occurred.

The association between alcohol, marijuana, illegal drug use and current use of E-cigarette among youth and young adults in Canada: results from Canadian Tobacco, Alcohol and Drugs Survey 2017

Background

E-cigarettes have grown in popularity around the world since 2003. Although marketed as a smoking cessation tool, e-cigarettes can lead to tobacco cigarette smoking in youth. In Canada, among all age groups, youth and young adults have the highest prevalence of e-cigarette use. The objective of this study was to assess the factors associated with e-cigarette use among youth and young adults in Canada, and to specifically examine the association between alcohol, marijuana and illicit drug use.

Methods

Data from the 2017 Canadian Tobacco, Alcohol and Drugs Survey were used. The sample was restricted to those aged 15–24 years (n = 10,322), and main outcome defined as ‘E-cigarette use in the past 30-days’. Multivariable logistic regression was performed to assess the association between the main outcome and substance use variables (illicit drug, marijuana and alcohol use), tobacco exposure variables, and demographic and health-related factors.

Results

6.2% Canadians aged 15–24 reported using e-cigarettes in the past 30-days, while 23.9% reported having ever tried e-cigarettes. Twenty-three percent of the past 30-day users reported using e-cigarettes every day and 72.5% of the past 30-day users reported having nicotine in their last e-cigarette. Additionally, youth aged 15–17 were 4.95 times more likely to be e-cigarette users as compared to those aged 22–24 (OR: 4.95, 95% CI: 3.1–7.9). Moreover, e-cigarette use was significantly associated with marijuana use (OR:4.17, 95% CI: 2.6–6.7) and alcohol use (OR: 5.08, 95% CI: 2.9–9.0), and approached significance with illicit drug use (OR: 1.68, 95% CI: 1.0–2.9). Furthermore, being a current smoker (OR: 2.93, 95% CI: 1.8–4.7) and male (OR: 2.28, 95% CI: 1.5–3.4) was significantly associated with the outcome.

Conclusion

This study is nationally representative and provides insight into e-cigarette use among youth and young adults aged 15–24 years. Given that e-cigarettes can be used as illicit drug delivery systems, more studies are needed to understand how Canadian youth and young adults are using e-cigarettes. Stricter restrictions on public e-cigarette smoking, and awareness campaigns informing youth of risks of e-cigarette smoking should be implemented.

The rise of e-cigarettes, pod mod devices, and JUUL among youth: Factors influencing use, health implications, and downstream effects

BACKGROUND

Electronic cigarettes (e-cigarettes) were first introduced in the U.S. market in 2006, with the more recent evolution of "pod-mod" e-cigarettes such as JUUL introduced in 2015. Although marketed as a smoking cessation tool, e-cigarettes are rarely used for this purpose in youth. This review aims to synthesize the literature regarding e-cigarette use among youth, and provides a resource for clinicians, educators, and families that helps answer commonly asked questions about e-cigarettes.

METHODS

PubMed, Scopus, and PsycINFO search was performed using search terms "Electronic Nicotine Delivery Systems," "e cigarettes," "e-cigarettes," "electronic cigarettes," "vaping," "JUUL," "e-cigs," and "vape pens." Search results were filtered to only include those related to adolescents and young adults.

RESULTS

E-cigarette use among youth is common, with rates of use increasing from 1.5% in 2011 to 20.8% in 2018. Pod mod devices such as JUUL have gained favor among youth for their sleek design, user-friendly function, desirable flavors, and ability to be used discreetly in places where smoking is forbidden. Adolescents are often uninformed about the constituents of e-cigarettes, and little is known about the long-term effects of e-cigarettes. Studies have suggested a "gateway" effect for combustible cigarettes and cannabis use.

CONCLUSIONS

E-cigarette use is becoming increasingly common among youth, leading to a myriad of questions and concerns from providers, educators, and family members. More research is needed to determine the ultimate public health impact of e-cigarette use. The authors provide a summary table of frequently asked questions in order to help clarify these common concerns.

Young people's perspectives of e-cigarette use in the home

There is concern that the emergence of e-cigarettes could result in an increase in young people's intake of, and exposure to, nicotine. This UK study used friendship group interviews to elicit the perspectives of young people from socioeconomically contrasting backgrounds regarding e-cigarettes. Young people from both advantaged and disadvantaged backgrounds described similar e-cigarette practices in the home environment, and, for both health and sensory reasons, viewed these as preferable to tobacco smoking. Space-related practices of adult e-cigarette use in the home were revealed to be more malleable than those of tobacco use. Results also highlighted that e-cigarettes offered young people new opportunities for nicotine consumption in the home. Methods of storing e-cigarettes in domestic spaces posed safety risks to younger children and easy access to e-cigarettes for others.

Gateway effects and electronic cigarettes

BACKGROUND

E-cigarettes are alleged to be a gateway to cigarette smoking in non-smokers. This study examines whether the gateway theory has value, whether the criteria to establish causality have been met and what type of evidence is required to test this theory.

ANALYSIS

Experiments are impractical, and we may not be able to test properly the gateway effects via observational studies that simply adjust for confounders. Multivariate models cannot eliminate all the variance in propensity to smoke captured by the variable 'vaping' because of the proximity of these two behaviours. It may be difficult to prove that vaping precedes smoking when product use co-occurs and when, in fact, smoking usually precedes vaping. The gateway theory is not compatible with either (1) the decrease in smoking prevalence observed in adolescents in countries where vaping increased or (2) an increase in smoking among teenagers after age restrictions were imposed on e-cigarette purchases. A spurious gateway effect can be produced artificially by mathematical models in which a propensity to use substances is correlated with opportunities to use substances. Finally, neither nicotine medications nor smokeless tobacco produce gateway effects. Available data are compatible with a common liability model in which people who are liable to use nicotine are more likely to use both e-cigarettes and cigarettes.

CONCLUSIONS

Despite its weaknesses and scant empirical support, the gateway theory of smoking initiation has had enormous political influence. Policies based on this theory will not have the intended effects if the association between vaping and smoking is explained by common liabilities.

What Factors are Associated with Electronic Cigarette, Shisha-Tobacco and Conventional Cigarette Use? Findings from a Cross-Sectional Survey of Australian Adolescents?

BACKGROUND

Adolescents' use of electronic cigarettes and shisha-tobacco increased in several countries during the 2000s, including in the United States, United Kingdom and Canada. Few studies have examined the factors associated with exclusive e-cigarette or shisha-tobacco use and whether adolescents using these substances exclusively differ from those using traditional cigarettes.

OBJECTIVES

To examine the socio-demographic and behavioural correlates of exclusive e-cigarette and exclusive shisha-tobacco use to those found for users of tobacco cigarettes and multiple nicotine products in Australian adolescents.

METHODS

Cross-sectional survey of smoking behaviours of a random sample of 4,576 students in the Australian state of Victoria aged 12-17 conducted between June 2014 and December 2014.

RESULTS

Overall, 14% of students had used an e-cigarette with 3% using e-cigarettes exclusively. 13% had used shisha-tobacco, with 2% using shisha-tobacco exclusively. Most students (65%) using e-cigarette and shisha-tobacco (67%) had also used tobacco cigarettes. After adjusting for demographic factors, students using e-cigarettes only were more likely to have never used cannabis or drink alcohol in the past year compared to tobacco cigarette users. Compared to tobacco cigarette users, students using only shisha-tobacco were younger, less likely to use cannabis or alcohol or have friends or parents who smoke.

CONCLUSIONS

Most Australian adolescents who use alternative nicotine and tobacco-related products do so in conjunction with tobacco cigarettes. Students using e-cigarettes or shisha-tobacco exclusively were less likely to use other substances. Australian longitudinal studies are needed to determine whether this group of students are on a pathway to traditional tobacco use.

E-cigarettes: A new hazard for children and adolescents

OBJECTIVES

Electronic cigarettes and fluid (e-cigarettes, e-fluid) are hazardous materials that when inhaled or ingested may pose significant health risks to children and adolescents. The objective of this work was to explore the spectrum of injury related to e-cigarette exposure among Canadian children and adolescents.

METHODS

A one-time survey was sent to all paediatricians in Canada. Information was collected on children and adolescents who presented with e-cigarette exposure (inhalation and ingestion cases) in the previous 12 months. Questions included the number of injuries and symptoms, in addition to age, sex, treatment setting, intentional e-cigarette use and how the products were accessed.

RESULTS

A total of 520 surveys were completed and returned, identifying 220 cases. Symptoms related to inhalation were present in 135 cases (43 unintentional, 92 intentional) and in 85 ingestion cases (35 unintentional, 50 intentional). For inhalation cases, most were male, aged 15 to 19 years, who sought treatment for nausea/vomiting, cough, throat irritation or acute nicotine toxicity in an outpatient clinic/office. Most inhalation cases reported e-cigarette use 2 to 3 days/week, and e-cigarettes purchases from a mall kiosk/store. For ingestion cases, most were male, aged 1 to 4 years presenting to an emergency department with nausea/vomiting, cough or respiratory irritation. Younger cases accessed e-fluid at home, older cases purchased in a mall kiosk/store. E-fluid flavours reported consumed were fruit, candy, and tobacco.

CONCLUSIONS

E-cigarettes, recently introduced into the North American market are hazardous to children and adolescents. Further investigation into the risks that e-cigarettes pose and ways to reduce exposure is needed to minimize injury.

E-cigarette use and quantity of cigarette smoking among adolescent cigarette smokers: A finite mixture model analysis

BACKGROUND

E-cigarette use is popular among adolescents and youth, but its long-term public health implications remain largely unknown. Much of the literature has focused on understanding the relationship between e-cigarette use and youth cigarette initiation. However, very little is known about e-cigarette use and cigarette quantity among those who continue to smoke cigarettes. The objective of the present study was to examine the association between current e-cigarette use and quantity of cigarette smoking.

METHODS

Cross-sectional data on current smokers were drawn from the 2014-2015 Canadian Student Tobacco, Alcohol and Drugs Survey among high school students (n = 1411). A finite mixture model (FMM) was employed to account for unobserved heterogeneity due to clusters of finite sub-populations.

RESULTS

Current e-cigarette users reported smoking more conventional cigarettes in the past week compared to non-e-cigarette users (t [1409] = 4.7998; p < 0.001 in unadjusted analysis). Results from a finite mixture regression showed that current e-cigarette use was significantly associated with the number of cigarettes smoked in the past week, but only among light smokers (IRR = 1.40; CI = 1.05-1.85). However, additional analyses found that the association between e-cigarette use and quantity of cigarette smoked varied by individual smoking pattern. An FMM with a group or class modelling using individual smoking pattern showed a weaker association between e-cigarette use and quantity of cigarette smoking.

CONCLUSION

Findings of this study suggest that the significant association between e-cigarette use and quantity of cigarette smoking may be driven by patterns of use among experimental or beginner smokers.

Prevalence of electronic nicotine delivery systems (ENDS) use among youth globally: a systematic review and meta-analysis of country level data

OBJECTIVE

To describe the prevalence and change in prevalence of electronic nicotine delivery systems (ENDS) use in youth by country and combustible smoking status.

METHODS

Databases and the grey literature were systematically searched to December 2015. Studies describing the prevalence of ENDS use in the general population aged ≤20 years in a defined geographical region were included. Where multiple estimates were available within countries, prevalence estimates of ENDS use were pooled for each country separately.

RESULTS

Data from 27 publications (36 surveys) from 13 countries were included. The prevalence of ENDS ever use in 2013-2015 among youth were highest in Poland (62.1%; 95%CI: 59.9-64.2%), and lowest in Italy (5.9%; 95%CI: 3.3-9.2%). Among non-smoking youth, the prevalence of ENDS ever use in 2013-2015 varied, ranging from 4.2% (95%CI: 3.8-4.6%) in the US to 14.0% in New Zealand (95%CI: 12.7-15.4%). The prevalence of ENDS ever use among current tobacco smoking youth was the highest in Canada (71.9%, 95%CI: 70.9-72.8%) and lowest in Italy (29.9%, 95%CI: 18.5-42.5%). Between 2008 and 2015, ENDS ever use among youth increased in Poland, Korea, New Zealand and the US; decreased in Italy and Canada; and remained stable in the UK.

CONCLUSIONS

There is considerable heterogeneity in ENDS use among youth globally across countries and also between current smokers and non-smokers. Implications for public health: Population-level survey data on ENDS use is needed to inform public health policy and messaging globally.

Frequency of E-cigarette Use, Health Status, and Risk and Protective Health Behaviors in Adolescents

OBJECTIVES

E-cigarettes (ECs) are increasingly popular among adolescents, who perceive them as "safer" than cigarettes. Although research has examined risk factors for adolescent EC use, little is known about how EC use correlates with health status and protective health behaviors.

METHODS

In all, 2488 adolescents (mean age = 17.31 years, SD = 0.67; 46% male) completed a survey on EC and cigarette use, physical and mental health, physical activity, diet, sleep, and alcohol and other drug (AOD) use. Logistic regression compared EC-only users to dual EC/cigarette users, cigarette-only users, and nonusers on these health factors. Among EC-only users, separate ordinary least-squares regression models assessed the effects of health status/behavior variables on frequency of past-year EC use, controlling for demographics and smokeless tobacco use.

RESULTS

User groups were similar on physical health and engagement in protective health behaviors (physical activity, sleep duration/quality, healthy diet), but EC-only users reported fewer mental health symptoms and less AOD use than dual or cigarette-only users. Among EC-only users, AOD use (all P < 0.0001) predicted more frequent EC use; healthy diet predicted less frequent use (P < 0.01).

CONCLUSIONS

EC-only use is associated with lower engagement in risky behaviors, but not better health status or higher engagement in protective health behaviors, compared with cigarette smoking. Dual EC/cigarette users may represent a particularly high-risk group due to their greater AOD use and cigarette consumption. Among "intermediate-risk" EC-only users, AOD use and unhealthy diet correlated with heavier use, and may be important targets for preventing escalation to more harmful tobacco use.

Susceptibility to cigarette smoking among middle and high school e-cigarette users in Canada

There is a growing concern that the historic reductions in tobacco consumption witnessed in the past decades may be undermined by the rapid increase in e-cigarette use. This study examined the association between e-cigarette use and future intention to smoke cigarettes among middle and high school students who had never smoked cigarettes. Data were drawn from the 2014-2015 Canadian Student Tobacco, Alcohol and Drugs Survey (n=25,637). A multivariable logistic regression model was used to examine the association between e-cigarette use and susceptibility to cigarette smoking. In addition, an inverse probability of treatment weighted regression adjustment method (doubly robust estimator), which models both the susceptibility to smoking and the probability of e-cigarette use, was conducted. About 10% of the students had ever tried an e-cigarette. There were higher rates of ever e-cigarette use among students in grades 10-12 (12.5%) than those in grades 7-9 (7.3%). Students who had ever tried an e-cigarette had higher odds of susceptibility to cigarette smoking (adjusted odds ratio=2.16, 95% confidence interval=1.80-2.58) compared to those that had never tried an e-cigarette. Current use of an e-cigarette was associated with higher odds of smoking susceptibility (adjusted odds ratio=2.02, 95% confidence interval=1.43-2.84). Similar results were obtained from the doubly robust estimation. Among students who had never smoked cigarettes, e-cigarette use was associated with a higher susceptibility to cigarette smoking.

A critique of the US Surgeon General's conclusions regarding e-cigarette use among youth and young adults in the United States of America

BACKGROUND

In December 2016, the Surgeon General published a report that concluded e-cigarette use among youth and young adults is becoming a major public health concern in the United States of America.

METHODS

Re-analysis of key data sources on nicotine toxicity and prevalence of youth use of e-cigarettes cited in the Surgeon General report as the basis for its conclusions.

RESULTS

Multiple years of nationally representative surveys indicate the majority of e-cigarette use among US youth is either infrequent or experimental, and negligible among never-smoking youth. The majority of the very small proportion of US youth who use e-cigarettes on a regular basis, consume nicotine-free products. The sharpest declines in US youth smoking rates have occurred as e-cigarettes have become increasingly available. Most of the evidence presented in the Surgeon General's discussion of nicotine harm is not applicable to e-cigarette use, because it relies almost exclusively on exposure to nicotine in the cigarette smoke and not to nicotine present in e-cigarette aerosol emissions. Moreover, the referenced literature describes effects in adults, not youth, and in animal models that have little relevance to real-world e-cigarette use by youth. The Surgeon General's report is an excellent reference document for the adverse outcomes due to nicotine in combination with several other toxicants present in tobacco smoke, but fails to address the risks of nicotine decoupled from tobacco smoke constituents. The report exaggerates the toxicity of propylene glycol (PG) and vegetable glycerin (VG) by focusing on experimental conditions that do not reflect use in the real-world and provides little discussion of emerging evidence that e-cigarettes may significantly reduce harm to smokers who have completely switched.

CONCLUSIONS

The U.S. Surgeon General's claim that e-cigarette use among U.S. youth and young adults is an emerging public health concern does not appear to be supported by the best available evidence on the health risks of nicotine use and population survey data on prevalence of frequent e-cigarette use. Nonetheless, patterns of e-cigarettes use in youth must be constantly monitored for early detection of significant changes. The next US Surgeon General should consider the possibility that future generations of young Americans will be less likely to start smoking tobacco because of, not in spite of, the availability of e-cigarettes.

Current Use of E-Cigarettes and Conventional Cigarettes Among US High School Students in Urban and Rural Locations: 2014 National Youth Tobacco Survey

PURPOSE

Adolescent tobacco use is higher in rural than in urban areas. While e-cigarette use is increasing rapidly among this age group, differences in prevalence between rural versus urban populations for this relatively novel product have not been explored. The purpose is to investigate whether location of school (rural-urban) is associated with e-cigarette use and dual use (defined as the use of both e-cigarettes and conventional cigarettes) among high school students.

DESIGN

Cross-sectional survey obtained using a stratified, 3-stage cluster sample design.

SETTING

United States.

PARTICIPANTS

A nationally representative sample of US high school students (N = 11 053) who completed the 2014 National Youth Tobacco Survey (NYTS); slightly more than half were urban (54%).

MEASURES

The NYTS measures tobacco-related knowledge, attitudes, and use behavior and demographics of students in the United States.

ANALYSIS

Weighted logistic regression assessed the relationships of urban-rural location with current e-cigarette use and dual use, adjusting for demographic factors, perceived risk, and social norms.

RESULTS

There were clear differences in patterns of adolescent e-cigarette and cigarette use in rural versus urban areas. Social norms and perceptions may play a role in understanding these differences.

CONCLUSION

Urban youth current cigarette smokers were nearly twice as likely as rural cigarette smokers to also use e-cigarettes. Reasons for urban-rural differences need to be taken into account when designing prevention programs and policy changes.

Prevalence and correlates of electronic cigarette use among Canadian students: cross-sectional findings from the 2014/15 Canadian Student Tobacco, Alcohol and Drugs Survey

BACKGROUND

Over the past decade, youth tobacco use has declined, and electronic cigarettes (e-cigarettes) have entered the market. The aims of this study were to describe the prevalence of e-cigarette use among youth in Canada, by province, across sociodemographic variables and smoking-related correlates; and to examine associations among e-cigarette use, sociodemographic variables and smoking-related correlates, with adjustment for other factors.

METHODS

The 2014/15 Canadian Student Tobacco, Alcohol and Drugs Survey, a biennial, school-based survey, was administered to students in grades 6-12 in all Canadian provinces. Logistic regression models were fitted to estimate odds of ever and past 30-day e-cigarette use by sociodemographic variables and smoking-related correlates.

RESULTS

A total of 336 schools from 128 school boards (47% of eligible schools approached) and 42 094 students (66% of eligible students approached) participated in the survey. In Canada, 17.7% (95% confidence interval [CI] 16.4%-18.9%) of students in grades 6-12 reported ever using e-cigarettes, and 5.7% (95% CI 5.2%-6.3%) reported past 30-day use. Substantial variation was observed across provinces. Female students had decreased odds of past 30-day use relative to male students (odds ratio [OR] 0.71, 95% CI 0.59-0.86), whereas current smokers (OR 10.0, 95% CI 6.66-15.02) and experimental smokers (OR 3.61, 95% CI 2.40-5.42) had increased odds relative to never smokers. Students who perceived that access was easy also had increased odds of using e-cigarettes relative to students who perceived that access was difficult (OR 3.86, 95% CI 2.96-5.03). Students who believed that regular use entailed slight risk (OR 0.68, 95% CI 0.52-0.88) and those who did not know risk levels (OR 0.31, 95% CI 0.21-0.46) had decreased odds compared with those perceiving no risk.

INTERPRETATION

Our data confirm that many youth used e-cigarettes in the 30 days preceding the survey, although rates were substantially higher among current and experimental smokers than among students who had never tried smoking.

Electronic cigarettes: what are they and what do they do?

Electronic cigarettes (ECIGs) use electricity to power a heating element that aerosolizes a liquid containing solvents, flavorants, and the dependence-producing drug nicotine for user inhalation. ECIGs have evolved rapidly in the past 8 years, and the changes in product design and liquid constituents affect the resulting toxicant yield in the aerosol and delivery to the user. This rapid evolution has been accompanied by dramatic increases in ECIG use prevalence in many countries among adults and, especially, adolescents in the United States. The increased prevalence of ECIGs that deliver nicotine and other toxicants to users' lungs drives a rapidly growing research effort. This review highlights the most recent information regarding the design of ECIGs and their liquid and aerosol constituents, the epidemiology of ECIG use among adolescents and adults (including correlates of ECIG use), and preclinical and clinical research regarding ECIG effects. The current literature suggests a strong rationale for an empirical regulatory approach toward ECIGs that balances any potential ECIG-mediated decreases in health risks for smokers who use them as substitutes for tobacco cigarettes against any increased risks for nonsmokers who may be attracted to them.

Overview of Electronic Nicotine Delivery Systems: A Systematic Review

CONTEXT

Rapid developments in e-cigarettes, or electronic nicotine delivery systems (ENDS), and the evolution of the overall tobacco product marketplace warrant frequent evaluation of the published literature. The purpose of this article is to report updated findings from a comprehensive review of the published scientific literature on ENDS.

EVIDENCE ACQUISITION

The authors conducted a systematic review of published empirical research literature on ENDS through May 31, 2016, using a detailed search strategy in the PubMed electronic database, expert review, and additional targeted searches. Included studies presented empirical findings and were coded to at least one of nine topics: (1) Product Features; (2) Health Effects; (3) Consumer Perceptions; (4) Patterns of Use; (5) Potential to Induce Dependence; (6) Smoking Cessation; (7) Marketing and Communication; (8) Sales; and (9) Policies; reviews and commentaries were excluded. Data from included studies were extracted by multiple coders (October 2015 to August 2016) into a standardized form and synthesized qualitatively by topic.

EVIDENCE SYNTHESIS

There were 687 articles included in this systematic review. The majority of studies assessed patterns of ENDS use and consumer perceptions of ENDS, followed by studies examining health effects of vaping and product features.

CONCLUSIONS

Studies indicate that ENDS are increasing in use, particularly among current smokers, pose substantially less harm to smokers than cigarettes, are being used to reduce/quit smoking, and are widely available. More longitudinal studies and controlled trials are needed to evaluate the impact of ENDS on population-level tobacco use and determine the health effects of longer-term vaping.

E-cigarettes and National Adolescent Cigarette Use: 2004-2014

BACKGROUND

E-cigarette use is rapidly increasing among adolescents in the United States, with some suggesting that e-cigarettes are the cause of declining youth cigarette smoking. We hypothesized that the decline in youth smoking changed after e-cigarettes arrived on the US market in 2007.

METHODS

Data were collected by using cross-sectional, nationally representative school-based samples of sixth- through 12th-graders from 2004-2014 National Youth Tobacco Surveys (samples ranged from 16 614 in 2013 to 25 324 in 2004). Analyses were conducted by using interrupted time series of ever (≥1 puff) and current (last 30 days) cigarette smoking. Logistic regression was used to identify psychosocial risk factors associated with cigarette smoking in the 2004-2009 samples; this model was then applied to estimate the probability of cigarette smoking among cigarette smokers and e-cigarette users in the 2011-2014 samples.

RESULTS

Youth cigarette smoking decreased linearly between 2004 and 2014 (P = .009 for ever smoking and P = .05 for current smoking), with no significant change in this trend after 2009 (P = .57 and .23). Based on the psychosocial model of smoking, including demographic characteristics, willingness to wear clothing with a tobacco logo, living with a smoker, likelihood of smoking in the next year, likelihood of smoking cigarettes from a friend, and use of tobacco products other than cigarettes or e-cigarettes, the model categorized <25% of current e-cigarette-only users (between 11.0% in 2012 and 23.1% in 2013) as current smokers.

CONCLUSIONS

The introduction of e-cigarettes was not associated with a change in the linear decline in cigarette smoking among youth. E-cigarette-only users would be unlikely to have initiated tobacco product use with cigarettes.

Adolescent Awareness and Use of Electronic Cigarettes: A Review of Emerging Trends and Findings

Adult electronic cigarette (e-cigarette) use is increasing globally, and early studies have suggested that similar trends may be observed among the adolescent population, albeit at lower levels. The current literature review presents data collected since 2014 from 21 cross-sectional studies and one cohort study that were all published in English. In particular, it focuses on awareness, ever use, past 30-day use, and regular use of e-cigarettes. The article suggests that adolescents are nearing complete awareness of e-cigarettes. Furthermore, in relation to ever use and past 30-day use, higher prevalence rates continue to be reported across time, especially in the United States. Nonetheless, reported regular use of e-cigarettes remains much lower than past 30-day use, although conclusions are limited due to inconsistencies with measurement and consequent lack of cross-cultural applicability. The majority of studies do not report whether adolescents use non-nicotine e-cigarettes. There is a current absence of longitudinal studies that explore any association between e-cigarettes and tobacco use and little qualitative data that may illuminate how and why adolescents use e-cigarettes. Through addressing these methodological limitations, future research will be able to inform health care and policy more effectively.

Looking beyond cigarettes: Are Ontario adolescents with asthma less likely to smoke e-cigarettes, marijuana, waterpipes or tobacco cigarettes?

OBJECTIVES

The purpose of this paper is to examine whether high school students in Ontario with asthma smoke cigarettes, waterpipes, marijuana or e-cigarettes more or less than those without asthma.

METHODS

The 2013 Ontario Student Drug Use and Health Survey provides self-report data on tobacco cigarettes, waterpipes, marijuana and e-cigarette smoking and asthma rates from 109 high schools in Ontario, Canada. Individual and social characteristics were also collected. Multiple binary logistic regression models measures the association with the various types of smoking in relation to asthma.

RESULTS

Adolescents with asthma have higher odds of smoking e-cigarettes or smoking any type including either cigarettes, waterpipes, marijuana or e-cigarettes. Respondents of lower socio-economic status had a higher odds of smoking marijuana or any type. Boys were more likely to smoke waterpipes, e-cigarettes or any type, while students in higher grades had a higher odds of smoking cigarettes, waterpipes, marijuana or any type.

CONCLUSIONS

Results from this study suggest that adolescents with asthma have a higher odds of smoking e-cigarettes than those without asthma, but no relationship was found for cigarettes, waterpipes or marijuana. Findings present some new challenges as technology changes how adolescents can smoke. Public health campaigns should target adolescents, especially those with asthma, to raise their awareness of the risks of all types of smoking including e-cigarettes.

Nicotine concentration of e-cigarettes used by adolescents

OBJECTIVE

E-cigarettes are popular among youth, but little is known about the nicotine concentrations of e-liquids used by adolescents.

MATERIALS AND METHOD

In Spring, 2014, we conducted cross-sectional surveys in four Connecticut high schools and two middle schools. Among past-30-day e-cigarette users (n=513, 45% female, mean age 15.9 [SD=1.4]), we examined what nicotine concentration adolescents typically used in their e-cigarettes (range 0-30mg/mL and "I don't know"). We first examined whether age, sex, smoking status, e-cigarette use frequency, and/or e-cigarette acquisition source were associated with using nicotine-free e-liquid, nicotine e-liquid, or not knowing the e-liquid nicotine concentration. Among nicotine users (n=185), we then examined whether the aforementioned variables were associated with using higher nicotine concentrations.

RESULTS

Adolescents reported using nicotine-free e-liquid (28.5%), nicotine e-liquid (37.4%), or not knowing their e-liquid nicotine concentration (34.1%). Nicotine users comprised more smokers and heavier e-cigarette users compared to nicotine-free e-liquid users and those who did not know their nicotine concentration. Nicotine users also comprised more males and were more likely to purchase e-cigarettes online or from tobacco shops compared to those who did not know their nicotine concentration. Among nicotine users, cigarette smoking, male sex, and purchasing e-cigarettes from tobacco shops predicted using higher nicotine concentrations.

CONCLUSIONS

Adolescents reported using e-liquids with variable nicotine concentrations. Smokers, males, and those who purchased their own e-cigarettes reported using the highest nicotine levels. Of concern, many adolescents were unaware of the nicotine concentration in their e-liquid, raising concerns about inadvertent nicotine exposure among youth.

Reasons for using flavored liquids among electronic cigarette users: A concept mapping study

BACKGROUND

Electronic cigarettes (ECIGs) aerosolize liquids often containing flavorants for inhalation. Few studies have examined the role of flavors in ECIG use. This study's purpose was to examine reasons for flavored ECIG use using a mixed-method approach, concept mapping (CM).

METHODS

Forty-six past 30-day adult ECIG users recruited from vape forums/conferences completed three online CM tasks. Participants brainstormed responses to a prompt: "A specific reason I use flavored e-liquid in my electronic cigarette product is…". The final 107 brainstormed statements were sorted by participants into groups of similar content. Participants rated each statement on a 7-point scale (1-Definitely NOT a reason to 7-Definitely a reason) based on a prompt: "This is a specific reason why I used flavored e-liquid in my electronic cigarette product in the past month." A cluster map was generated from participants' sorting and ratings using CM statistical software. Cluster mean ratings were compared.

RESULTS

Analysis revealed five clusters of reasons for flavored ECIG use including Increased Satisfaction/Enjoyment, Better Feel/Taste than Cigarettes, Variety/Customization, Food Craving Suppression, and Social Impacts. Statements in the Increased Satisfaction/Enjoyment and Better Feel/Taste than Cigarettes clusters were rated significantly higher than statements from other clusters (ps<0.05). Some statements indicated flavors were perceived as masking agents for nicotine or other bad tastes associated with cigarette smoking making ECIG use more palatable.

CONCLUSIONS

Flavored ECIGs are used for many reasons. Some statements suggested flavors may increase the rewarding and possible addictive effects of ECIGs. These results support continued examination of the role of flavors and ECIG use behaviors.

What are kids vaping? Results from a national survey of US adolescents

OBJECTIVE

To examine what substances US youth vape.

METHODS

Data come from Monitoring the Future, an annual, nationally representative survey of USA 12th-grade, 10th-grade and 8th-grade students. Respondents reported what substance they vaped the last time they used a vaporiser such as an e-cigarette.

RESULTS

Among students who had ever used a vaporiser, 65-66% last used 'just flavouring' in 12th, in 10th and in 8th grade, more than all other responses combined. In all three grades, the percentage using 'just flavouring' was above 57% for males, females, African-Americans, Hispanics, Whites, and students both with and without a parent with a college degree. Nicotine use came in a distant second, at about 20% in 12th and 10th grade and 13% in 8th grade. Taking into account youth who vaped nicotine at last use increases national estimates of tobacco/nicotine prevalence in the past 30 days by 24-38% above and beyond cigarette smoking, which is substantial but far less than estimates that assume all vaporiser users inhale nicotine.

CONCLUSIONS

These results challenge the common assumption that all vaporiser users inhale nicotine. They (a) call into question the designation of vaporisers and e-cigarettes as ENDS ('Electronic Nicotine Delivery System'), (b) suggest that the recent rise in adolescent vaporiser use does not necessarily indicate a nicotine epidemic, and (c) indicate that vaporiser users can be candidates for primary prevention programmes. Finally, the results suggest the importance of developing different rationales for the regulation of vaporiser devices as compared to the regulation of substances marketed for vaporiser use.

Reported electronic cigarette use among adolescents in the Niagara region of Ontario

BACKGROUND

Use of electronic cigarettes (e-cigarettes) among adolescents has not been fully described, in particular their motivations for using them and factors associated with use. We sought to evaluate the frequency, motivations and associated factors for e-cigarette use among adolescents in Ontario.

METHODS

We conducted a cross-sectional study in the Niagara region of Ontario, Canada, involving universal screening of students enrolled in grade 9 in co-operation with the Heart Niagara Inc. Healthy Heart Schools' Program (for the 2013-2014 school year). We used a questionnaire to assess cigarette, e-cigarette and other tobacco use, and self-rated health and stress. We assessed household income using 2011 Canadian census data by matching postal codes to census code.

RESULTS

Of 3312 respondents, 2367 answered at least 1 question in the smoking section of the questionnaire (1274 of the 2367 respondents [53.8%] were male, with a mean [SD] age of 14.6 [0.5] yr) and 2292 answered the question about use of e-cigarettes. Most respondents to the questions about use of e-cigarettes (n = 1599, 69.8%) had heard of e-cigarettes, and 380 (23.8%) of these respondents had learned about them from a store sign or display. Use of e-cigarettes was reported by 238 (10.4%) students. Most of the respondents who reported using e-cigarettes (171, 71.9%) tried them because it was "cool/fun/new," whereas 14 (5.8%) reported using them for smoking reduction or cessation. Male sex, recent cigarette or other tobacco use, family members who smoke and friends who smoke were strongly associated with reported e-cigarette use. Reported use of e-cigarettes was associated with self-identified fair/poor health rating (odds ratio [OR] 1.9 (95% confidence interval [CI] 1.2-3.0), p < 0.001), high stress level (OR 1.7 (95% CI 1.1-2.7), p < 0.001) and lower mean (33.4 [8.4] × $1000 v. 36.1 [10.7] × $1000, p = 0.001) and median [interquartile range] (26.2 [5.6] × $1000 v. 28.1 [5.7] × $1000) household incomes.

INTERPRETATION

Use of e-cigarettes is common among adolescents in the Niagara region and is associated with sociodemographic features. Engaging in seemingly exciting new behaviours appears to be a key motivating factor rather than smoking cessation.

Electronic cigarette use among adolescents: a cross-sectional study in Hong Kong

Background

Little is known about electronic cigarette (e-cigarette) use among Chinese adolescents. We examined the prevalence of current (past 30-day) e-cigarette use and its associated factors in a large sample of adolescents in Hong Kong.

Methods

We analyzed data of the School-based Survey on Smoking among Students 2012/13 from a representative sample of 45,857 secondary school students (mean age: 14.8 ± 1.9). We conducted chi-square tests and t-test to compare current e-cigarette use by covariates. We used multivariable logistic regression to examine the association between current e-cigarette use and demographic variables, parental smoking, peer smoking, knowledge about the harm of cigarette smoking, attitudes toward cigarette smoking, cigarette smoking status, use of other tobacco products, and alcohol consumption.

Results

Overall, 1.1 % of students reported current e-cigarette use. Of e-cigarette users, 11.7 % were never-cigarette smokers, 15.8 % were experimental cigarette smokers, 39.3 % were former cigarette smokers, and 33.2 % were current cigarette smokers. Current e-cigarette use was associated with male sex, poor knowledge about the harm of smoking, cigarette smoking, use of other tobacco products, and alcohol consumption.

Conclusions

Surveillance and intervention efforts should address a wide range of tobacco products, including e-cigarettes. Tobacco cessation programs should also address alcohol use collectively. Policies prohibiting e-cigarette sales to minors may help prevent e-cigarette uptake among adolescents.

Cigarette Smoking and Electronic Cigarettes Use: A Meta-Analysis

Increasing evidence indicates that cigarette smoking is a strong predictor of electronic cigarettes (e-cigarettes) use, particularly in adolescents, yet the effects has not be systematically reviewed and quantified. Relevant studies were retrieved by searching three databases up to June 2015. The meta-analysis results were presented as pooled odds ratios (ORs) with 95% confidence intervals (CIs) calculated by a random-effects model. Current smokers were more likely to use e-cigarette currently (OR: 14.89, 95% CI: 7.70–28.78) and the probability was greater in adolescents than in adults (39.13 vs. 7.51). The probability of ever e-cigarettes use was significantly increased in smokers (OR: 14.67, 95% CI: 11.04–19.49). Compared with ever smokers and adults, the probabilities were much greater in current smokers (16.10 vs. 9.47) and adolescents (15.19 vs. 14.30), respectively. Cigarette smoking increases the probability of e-cigarettes use, especially in current smokers and adolescents.

Prevalence and correlates of electronic cigarette use among adolescents in Greece: a preliminary cross-sectional analysis of nationwide survey data

INTRODUCTION

This study reports the prevalence of electronic cigarette (e-cigarette) use among adolescents in Greece and explores how dual smokers of e-cigarettes and combustible (conventional) cigarettes differ from smokers of only combustible cigarettes across socio-demographic, familial, psychosomatic health and substance use characteristics.

METHODS

Self-reports on smoking were collected from a nationally representative sample of 1320 15-year-old Greek students in the 2014 Health Behaviour in School-aged Children study. Bivariate and multivariable logistic regression analyses were carried out with dependent variables a) lifetime smoking conventional cigarettes and b) lifetime e-cigarette use among lifetime smokers.

RESULTS

About 36.9% of 15-year-olds reported lifetime smoking of conventional cigarettes, and 16.6% lifetime use of e-cigarettes, mostly experimenting (0.5% reported current e-cigarette use). Six in 7 ever e-cigarette smokers had smoked conventional cigarettes. Peers who smoke and lifetime cannabis use were significant correlates of both lifetime conventional cigarette and e-cigarette smoking, but more strongly for smoking conventional cigarettes. Alcohol use and low parental monitoring correlated with tobacco smoking but not e-cigarette use. Girls were more likely than boys to report lifetime use of tobacco, but, among lifetime smokers, boys had almost seven times the odds of girls of e-cigarette use. In lifetime smokers, low life satisfaction in females and current smoking of conventional tobacco were independently associated with the experimentation with e-cigarettes.

CONCLUSIONS

Experimental use of e-cigarettes is relatively widespread among adolescents in Greece. Targeted interventions should focus on male smokers and the role of peer processes and cannabis use in the risk of experimenting with e-cigarettes.