E-cigarette attitudes and behaviours amongst 15-30-year-olds in the UK

Abstract Background The use of e-cigarettes has been rising in the UK, particularly by young people. This study investigated behaviours, attitudes and beliefs about e-cigarettes amongst 15–30-year-olds in the UK. Methods An online survey was administered to a sample of 1009 15–30-year-olds in the UK. Results About one in five participants currently used e-cigarettes at least monthly, with 1 in 10 using them daily. Amongst those using e-cigarettes at least monthly, 90% had used e-cigarettes containing nicotine. E-cigarettes were mainly obtained from vape shops and used at home. Having friends who used e-cigarettes and using them to help quit/reduce smoking were the most common reasons for vaping. About half of participants had been exposed to e-cigarette advertising, especially online, and warning labels on e-cigarettes. Most participants agreed that e-cigarettes are addictive (75%), help people quitting smoking (64%) and are bad for health (63%). Previous or current tobacco smokers were 9 and 22 times more likely to use e-cigarettes than never smokers, respectively. Perceiving e-cigarettes as harmful was associated with a 40% lower likelihood of use. Conclusion Raising awareness on the uncertain long-term consequences of vaping and regulation of marketing and sales are crucial to protect young people in the UK.


Introduction
The prevalence of tobacco smoking has been steadily declining over the past decades in the UK. 1 In 2021, 6.6 million people or 13.3% of people aged 18 years and over smoked cigarettes, which is the lowest proportion of current smokers since 2011. 1 This reduction resulted from comprehensive public health policies and programmes, such as restrictions on marketing and selling of tobacco products and their use in public environments, together with a reduction in social acceptability of smoking motivated by growing concerns about its detrimental effect on health. 2 The impact of public health policies has been increased by the development and implementation of diverse pharmacological therapies to support smoking cessation, including a variety of nicotine replacement products. 3ectronic cigarettes, also known as e-cigarettes, are battery-operated devices invented in 2003 as an alternative to tobacco smoking. 4In addition to the battery component, an e-cigarette comprises an atomiser and a cartridge containing either a nicotine or a non-nicotine solution.When the device is operated, the battery heats the liquid in the cartridge and the atomiser vaporizes the liquid and emits a vapour (hence, the common designation of 'vaping') that the user inhales.E-cigarettes have been promoted as an effective aid to quit or reduce tobacco smoking because they may be less harmful than tobacco products, at least in the short term. 5However, whilst the updated tobacco guidelines issued by the National Institute for Health and Care Excellence (NICE) in the UK recommend the use of e-cigarettes to support smoking cessation in adults, they acknowledge the uncertainty on the short-and long-term health effects of e-cigarettes, especially for children, young people and pregnant women. 6he efficacy of e-cigarettes compared with other forms of nicotine replacement therapy in promoting and sustaining smoking cessation and treating dependence is controversial internationally. 7First, the chemicals contained in the solution and vapour may have harmful effects on the lungs, such as vaping-associated lung injury. 8Second, most e-cigarettes contain nicotine and hence are at least as addictive as regular cigarettes. 9Marketing of e-cigarettes as safer alternatives to tobacco together with their additive potential could promote their use and facilitate the transition to more harmful forms of smoking, such as tobacco. 10These concerns underpin the regulation of the composition, marketing and sales of ecigarettes.For instance, in the UK, chemicals that have been associated with vaping-associated lung injury are not allowed in e-cigarette liquids, 8,11 and marketing and advertising of ecigarettes, particularly to young people, is prohibited. 12otwithstanding public health information campaigns promoting e-cigarettes solely as a smoking cessation aid rather than as a harmless smoking alternative, 13 the popularity of ecigarettes has been steadily rising for the past years in the UK. 1 In 2021, it was estimated that 4 million or 7.7% of people aged 16 years and over currently used an e-cigarette daily or occasionally, which represents an increase on the estimate of 6.4% in 2020. 1 Furthermore, 2021 was the first year since data collection began in 2014 that young people aged 16-24 years reported the highest proportion of vapers (daily and occasional) at 11.1% in comparison to other age groups. 1 Amid growing concerns about the impact of e-cigarettes, understanding what is driving the upward trend of their use by young people is crucial to inform public health policy and interventions.Therefore, this study aimed to explore a wide range of vaping-related exposures, attitudes and behaviours amongst 15-30-year-olds in the UK.

Participants
As part of a larger international study, 14 an ISO-accredited social research agency (Pureprofile) was commissioned to recruit a national sample of ∼1000 residents in the UK aged 15-30 years from their web panel.Quotas were applied to ensure the sample had a proportionate distribution between genders and year groups.This quota system was designed to obtain a broadly representative sample and achieved adequate power to detect differences between demographic groups.Between October and November 2021, potential respondents were sent an e-mail invitation to complete an online survey taking ∼20 min.Participants were explained the topic and purpose of the study by a participant information letter once they clicked on the link to access the survey.The study was approved by a university Human Research Ethics Committee and all respondents provided informed consent.

Survey
The survey included questions related to respondent demographics (gender, age, income, education and postcode to assess geographical distribution), vaping/smoking products used, [15][16][17] how e-cigarettes are obtained 18 and where they are used (new question developed for this survey), motivations for vaping, 17,19 exposure to others' vaping behaviours, 17,20 exposure to e-cigarette advertising 17 and beliefs about ecigarettes. 21,22The questions were based on the referenced sources and adapted as required considering the purpose and target population of the survey.To equivalize item wording across substances, the e-cigarette and tobacco use items asked respondents to report if they 'Never used', 'Previously used' or 'Currently use' a range of products, including e-cigarettes, e-hookahs/pipes, cannabis e-cigarettes, tobacco cigarettes, cigars and pipes.Use was described in terms of 'even just once or twice'.

Data analysis
Descriptive analyses were carried out for the included variables and stratified by gender, age and smoking status.Differences between subgroups were tested using chi-squared test.Because of the large number of comparisons, a Pvalue < 0.001 was considered statistically significant.For the analysis of behaviours, only participants who used e-cigarettes at least once monthly were included.For the analyses of exposures and beliefs, participants who said they did not know about e-cigarettes were excluded.Multivariable logistic regression was used to identify factors associated with ever (i.e.previous or current) e-cigarette use.Variables included in the regression were respondent gender, age, education, income and tobacco use status; perceived harmfulness and addictiveness (continuous variable); numbers of family members and friends who use e-cigarettes; and exposure to ecigarette advertising (binary variable).The latter was coded as exposure to at least one of the four assessed forms of e-cigarette advertising (television/cinema/streaming services, internet, social media and corner stores/supermarkets/petrol stations).The significance threshold for the regression analysis was P < 0.05.

E-cigarette-related behaviours and motivations amongst at least monthly current e-cigarette users
Amongst the 1009 participants, 222 (22.0%) reported currently using e-cigarettes at least monthly (Table 1), with no meaningful differences between women (20.6%) and men (22.6%).People aged 15-19 years were less likely to use ecigarettes at least monthly than older age groups (15.6% for 15-19-year-olds versus 25.8% for 20-25-year-olds and 24.3% for 26-30-year-olds-results not shown in tables).Current smokers were the most likely to use e-cigarettes (44.9%) followed by previous smokers (28.5%), whereas never smokers used them rarely (2.3%) (results not shown in tables).
A total of 102 (45.9%) of those who used e-cigarettes at least monthly reported using them daily.Ever use of ecigarettes containing nicotine was reported by about 9 in 10 of those who used e-cigarettes at least monthly (199, 89.6%), whereas ever use of cannabis via e-cigarettes was reported by about one in three 72 (32.4%).Prescriptions for e-cigarettes were overall uncommon (34, 15.3%) in this group.
Over two-thirds of participants had one or two relatives who use e-cigarettes (447, 48.1% and 278, 29.9%, respectively) (Table 3).About three in four participants had up to three close friends who use e-cigarettes (one friend: 286, 30.8%; two friends: 212, 22.8%; three friends: 218, 23.4%).Participants had been widely exposed to e-cigarette advertising, including on social media (601, 64.6%); corner shops, supermarkets or petrol stations (512, 61.5%); the internet (335, 36.0%);and/or TV, streaming services or a movie at the cinema (256, 27.5%).About half of participants had been exposed to warning labels on e-cigarettes (489, 52.6%).About one in three had seen a warning label advising that e-cigarettes contain nicotine and nicotine is addictive (329, 35.4%), and one in five had seen a warning label cautioning that the longterm health risks associated with e-cigarettes are unknown (204, 21.9%).

Factors associated with ever use of e-cigarettes
Age and gender were not associated with ever use of ecigarettes (Table 4).The strongest predictors of using ecigarettes were previous or current tobacco smoking (OR 8.50 95% CI [5.15-14.04],P < 0.001 and 22.28 [12.19-40.71],P < 0.001, respectively).The likelihood of using e-cigarettes increased as the number of relatives or close friends using e-cigarettes increased (1.95 [1.49-2.56],P < 0.001 and 1.57 [1.32-1.88],P < 0.001, per each additional relative and close friend, respectively).Perceiving e-cigarettes as harmful was associated with a ∼40% lower likelihood of using e-cigarettes (0.64 [0.49-0.83],P < 0.001).Values represent number (%) of participants who selected 'Agree' or 'Strongly Agree' on a 5-point Likert scale from 'Strongly Disagree' to 'Strongly Agree'.Participants who responded that they did not know about e-cigarettes were excluded from these analyses.a Significant difference between columns for the same variable (sex, age, smoking) at P < 0.001.This refers to differences between that column and all other columns for the same variable.Participants who responded that they did not know about e-cigarettes were excluded from these analyses.Significant difference between columns for the same variable (sex, age, smoking) at P < 0.001.This refers to differences between that column and all other columns for the same variable.

Main finding of this study
In a sample of 1009 15-30-year-olds in the UK, about one in five currently used e-cigarettes at least monthly, with one in ten using them daily.Amongst vapers, e-cigarettes were similarly used by women and men and appeared to be more used by those over the age of 20 years.Current smokers were the most likely to use e-cigarettes followed by previous smokers, with low use reported by never smokers.Amongst those using e-cigarettes at least monthly, about 90% reported having used e-cigarettes containing nicotine and about one in three said they had used e-cigarettes containing cannabis.Approximately one in seven at least once monthly vapers had medical prescriptions for e-cigarettes.Ecigarettes were mainly obtained from vape shops and used at home (either their own or someone else's), parties and the workplace.Having friends who used e-cigarettes and using them to help quit or reduce the use of tobacco cigarettes were the most common reasons for using e-cigarettes.Most participants agreed that e-cigarettes are addictive, contain chemicals and nicotine, help people quitting smoking and are bad for health.About half of participants had been exposed to warning labels on e-cigarettes and e-cigarette advertising, especially online.Previous or current tobacco smokers were 9 and 22 times more likely to use e-cigarettes than never smokers, respectively.Perceiving e-cigarettes as harmful was associated with a 40% lower likelihood of use.

What is already known on this topic
Our estimated prevalence of using e-cigarettes at least monthly was approximately twice of that reported by the Office of National Statistics in the UK in 2021 (11% for daily or occasional vapers aged 16-34 years), when this survey was conducted. 1Our prevalence of vaping at least once monthly was also higher than official statistics for current (45 versus 25%) and previous cigarette smokers (29 versus 15%). 1 Use of e-cigarettes by never smokers in our survey was low (about 2%), which is broadly comparable to the estimated prevalence from several national studies (0.7%). 23Taken together, these comparisons suggest that our sample might have been enriched with vapers, possibly because they were more likely to respond to this survey.It is also possible that different definitions of vaping may have contributed to the observed discrepancy in prevalence between studies.Therefore, our findings may not be generalizable to the population of 15-30-year-olds, but they may be indicative of the behaviour, attitudes and beliefs of current vapers in the UK.

What this study adds
Our study adds to the official statistics by including under 18-year-olds, who are not included in the national survey.
We found important differences between under 20-year-olds, which includes under 18-year-olds to whom it is illegal to sell e-cigarettes, and those aged 20 and over.For instance, under 20-year-olds were more likely to use disposable e-cigarettes, which are cheaper than other devices and have been identified as drivers of vaping amongst teenagers. 24They were also more likely to have used fruit flavours, which seem to be particularly appealing to adolescents and hence promoted by targeted marketing campaigns. 25Under 20-year-olds were more likely to vape at parties and because of friends' influence as well as to have four or more friends who vaped than older age groups.This highlights the importance of peer pressure in this age group, which has been exploited by industry. 26lthough our findings are based on under 20-year-olds, they broadly support the adoption by the UK government of evidence-based policies that address the factors that encourage vaping by under 18-year-olds, such as reducing the appeal by regulating product characteristics, forbidding advertising and raising awareness about harms in education campaigns. 27ual use (i.e.concomitant use of tobacco and e-cigarettes) was very common, with ∼45% of current smokers using e-cigarettes at least monthly.It is uncertain whether dual smokers started by using e-cigarettes and then transitioned to tobacco cigarettes or vice-versa.This is a relevant question for future research and policy because of ongoing concerns that e-cigarettes might be a gateway to tobacco smoking visà-vis the rising prevalence of vaping amongst young people in the UK. 10 Furthermore, previous research has shown that users of e-cigarettes were two to four times more willing to try tobacco compared with those who had never used any tobacco product, which seemed partly mediated by positive expectations about smoking. 28,29Although recent evidence suggests that many young people who start using e-cigarettes and transition to smoking may not continue after initiation of vaping, 30 it is important to validate these findings in other cohorts and investigate whether e-cigarette users in youth have an increased risk of becoming smokers later in life.Evidence is also lacking on whether short-term or intermittent use of e-cigarettes in youth can lead to negative health outcomes in adulthood.
Environmental concerns about vaping have been increasing recently, particularly fuelled by the rise in disposable devices. 31Although our cross-sectional survey cannot investigate trends over time, the finding that about three in four vapers aged 15-19 years used disposable e-cigarettes suggests they are particularly common amongst teenagers, who may keep using them if they continue using e-cigarettes through adulthood.This is supported by a recent report from the public health charity 'Action on Smoking and Health' in the UK, which showed that, for the first time in 2022, disposable e-cigarettes were the devices most frequently used by 11-18year-olds in Britain (52.0%compared with 7.7% in 2021). 32nvironmental concerns because of this recent increase in use of disposable devices, especially by teenagers, add to concerns about harmful health consequences of vaping in this population. 33Together they underpin measures adopted by the UK government to prevent use e-cigarettes by under 18-year-olds. 34These include enforcing sales and marketing restrictions, such as plain packaging, which may be especially effective at reducing the appeal to young people. 35he results of this study suggest that influence of relatives and friends is an important driver of using e-cigarettes.The influence of significant others, particularly friends and family, on use of e-cigarettes by young people has been documented by previous studies in other countries. 36Understanding how complex social networks, both in person and online (e.g. on social media), can either promote or prevent vaping amongst young people is crucial to design effective public health campaigns raising awareness on the unknown health effects of e-cigarettes and discouraging their use. 37Individual-based interventions that fail to account for the influence of family and friends are unlikely to succeed for young people who do not have the support network needed to stop vaping and smoking and are immersed in an environment where they are consistently exposed to e-cigarettes and/or tobacco.Therefore, interventions based in schools or targeting all the smokers and/or e-cigarette users in a household or similar social group may be more likely to be successful in the long-term. 38he fact that perceiving e-cigarettes as harmful was associated with a 40% lower likelihood of using them demonstrates the importance of raising awareness on the already established harms of e-cigarettes, such as vaping-related lung injury.E-cigarettes are relatively recent and, thus, their potential risks, particularly associated with prolonged used, remain poorly understood. 39In addition, only half of e-cigarette users and less than a third of current tobacco smokers in our study reported having seen warning labels on packages of e-cigarettes.This is in keeping with evidence from other national surveys in the UK, which showed lack of awareness about the relative risks of smoking and vaping. 23Taken together, these findings demonstrate the need for stronger policy on labelling along with well-designed public health campaigns to inform about the potential harms of using e-cigarettes and prevent misinformation from luring young people into vaping.
The findings of our study are relevant to inform public health policy.Despite accruing evidence on their costeffectiveness to aid reducing or quitting tobacco smoking, 6 controversy remains about net population benefit amidst growing concerns about long-term health implications. 40ontrary to other countries that, in the absence of robust evidence, have adopted a precautionary approach to ecigarettes, 41 the UK has widely endorsed e-cigarettes as an aid to quitting or reducing tobacco smoking.The updated NICE guidelines on tobacco smoking published in 2021 recommend giving advice on how to use e-cigarettes to smokers who demonstrate interest in using them, including that they are likely to be 'substantially less harmful than smoking', but evidence is lacking on 'whether there are longterm harms from e-cigarette use'. 6Nonetheless, e-cigarettes were considered cost-effective and their recommendation by NICE guidelines may have influenced the Office for Health Improvement and Disparities, the public health arm of the Department of Health and Social Care, to recommend their use as a first-line therapy alongside medicinally licensed stop smoking products. 42Furthermore, the Crown Commercial Services added vaping product catalogues to existing public sector procurement frameworks in April 2023. 42This is likely to result in a significant increase in medical prescriptions of e-cigarettes, which our study suggests were rare in 2021 as only 15% of users were prescribed e-cigarettes.
The relatively lenient approach to e-cigarettes in the UK contrasts with World Health Organization recommendations to limit availability of e-cigarettes and minimize uptake because of concerns about their adverse health effects and the potential for tobacco use to be renormalized through public exposure to vaping. 43It is thus critical that policy and regulation are updated as evidence emerges on the long-term consequences of using e-cigarettes across the life course, particularly when used concomitantly with tobacco and by those who may be particularly vulnerable to harmful effects, such as young people. 44

Limitations of this study
This study has some limitations.First, it is possible that our findings are not generalizable to the general population of 15-30-year-olds even if quotas were used to obtain a roughly representative sample for demographic variables.Our study sample seems to have a higher prevalence of vaping than official statistics, which suggests our findings may be broadly generalizable to e-cigarette users but not to the general population of 15-30-year-olds.Second, many of the survey items did not differentiate between nicotine and non-nicotine ecigarettes because of the inconsistent labelling of e-cigarettes, which meant that participants could be unsure about the contents of the e-cigarettes they used.Third, the factors associated with using e-cigarettes may not be causal as this is a cross-sectional study.Fourth, under 18-year-olds represented only about 13% of the study population and, hence, further studies are warranted in this age group.

Conclusion
E-cigarettes seem to be used by a substantial proportion of 15-30-year-olds in the UK.Although they appear to be mainly used by current or former smokers, their regular use by under 20-year-olds is concerning.Further research is warranted to understand the drivers of their illegal use by under 18-yearolds.It is imperative that support for e-cigarettes as aids to reduce or stop smoking by public health authorities is matched by raising awareness about their uncertain impact and tight regulation on labelling, advertising and sales.

Table 1 E
-cigarette-related behaviours and motivations amongst at least monthly current users by gender, age and smoking status-n (%)

Table 3
External influences by gender, age and smoking status-n (%)

Table 4
Factors associated with ever use of e-cigarettes