Although conventional cigarette smoking among adolescents and emerging adults has declined over time, a review of international studies has provided evidence that the use of e-cigarettes has increased with a pooled international prevalence from previous studies of 15.3% for lifetime prevalence, 7.7% for current prevalence, and 4.0% for dual use prevalence (Kim et al., 2022). This work also indicated the highest current prevalence found in Canada (31.4%) and the lowest in South Korea (1.7%) (Kim et al., 2022). Data from Canada has shown that after the introduction of electronic vaping products (e.g., e-cigarettes) in Canada, adolescent e-cigarette use increased substantially in a short timeframe. In 2018 to 2019, it was reported that 20% of Canadian adolescents in grades 7 to 12 used e-cigarettes in the past month, a 14% increase from 2014 to 2015, and 34% previously tried e-cigarettes (Health Canada, 2019). It was also reported that 90% of past-month vapers had used products containing nicotine (Health Canada, 2019). In a recent study using qualitative focus groups with Canadian youth, nicotine was noted as the main reason for vaping (Health Canada, 2020). Many participants indicated a preference to vape products containing high levels of nicotine in order to experience a head rush, and there was little inclination to use products with less nicotine for that reason (Health Canada, 2020).

Originally marketed for smoking cessation, electronic vaping products are considered less harmful than cigarettes due to the absence of tobacco, fewer and lower levels of toxic chemicals, and a different mode of delivery involving aerosolized liquid rather than combustion (Health Canada, 2022). Vaping liquids typically contain propylene glycol, vegetable glycerin, other chemicals including flavouring compounds, and may contain nicotine. Although nicotine is not known to cause cancer, it is not without health risks especially at young ages. Nicotine is highly addictive and is associated with harmful effects on adolescent brain development and cognition (Health Canada, 2022). In addition, vaping has been linked to respiratory, cardiovascular, and other health conditions (Lyzwinski et al., 2022). In some cases, the harmful effects of vaping have been attributed to specific chemical additives. For example, cases of vaping-associated lung injury were found to result from tetrahydrocannabinol and vitamin-E acetate (Lyzwinski et al., 2022). The long-term consequences of vaping are unknown.

A growing literature indicates that young people who use electronic vapor products are more likely to initiate the use of other substances, though little is known about the Canadian context. Based on data from the 2017 Canadian Tobacco, Alcohol, and Drugs Survey (CTADS), Mehra et al. (2019) found that e-cigarette use was associated with alcohol and cannabis use among 15- to 24-year-olds. However, due to the cross-sectional design of the CTADS, it was unclear whether e-cigarette use was associated with incident alcohol and cannabis use (Mehra et al., 2019). Longitudinal studies conducted in other countries have found that adolescent vaping predicted combustible cigarette smoking and cannabis use (Bentivegna et al., 2021; Seidel et al., 2022; Soneji et al., 2017; Staff et al., 2022). Fewer studies have investigated the association between vaping and subsequent alcohol consumption. With a sample of emerging adults, Evans-Polce and colleagues (2020) found that e-cigarette use was prospectively associated with the use of cigarettes, cannabis, and non-medical prescription drugs, but not alcohol use, in adjusted models. Adolescent vaping may also be associated with increased risk of concurrent polysubstance use (defined as the use of more than one substance during a certain timeframe [e.g., past year]) and simultaneous polysubstance use (the use of more than one substance on the same occasion) (Østergaard et al., 2016).

More recent Canadian data indicate that the prevalence of adolescent vaping does not differ between males and females (Health Canada, 2019), though vaping was found to be more common among males in earlier surveys (Health Canada, 2018). It was also reported that prevalence estimates of alcohol and cannabis in Canadian adolescents did not vary by sex, but the use of tobacco products was higher among males compared to females (Health Canada, 2019). Whether sex differences exist in the associations between adolescent vaping and use of other substances or polysubstance use is not known.

Furthermore, understanding risk factors for concurrent and simultaneous polysubstance use is important for prevention programs. Adverse childhood experiences (ACEs), peer victimization, and mental illness are risk factors for many harmful outcomes across the lifespan (e.g., Copeland et al., 2013; Copeland et al., 2015; Erskine et al., 2015; Hughes et al., 2017; Merrick et al., 2017; Moore et al., 2017), including substance use (Afifi et al., 2020a, b; Duke, 2018; Fortier et al., 2022; Krygsman & Vaillancourt, 2022; Riehm et al., 2019). Yet, to our knowledge, no studies have investigated among youth the associations between ACEs or peer victimization and (a) concurrent polysubstance use that includes vaping or (b) simultaneous polysubstance use. Also, few studies have analyzed risk factors such as mental health problems or sex differences.

Alvarez-Alonso et al. (2016) examined several types of abuse, neglect, and psychiatric disorders in relation to concurrent polysubstance use among a sample of treatment-seeking adolescents, but did not include vaping or simultaneous use. Williams et al. (2021) analyzed patterns of concurrent polysubstance use comprising alcohol, cannabis, cigarettes, and e-cigarettes, but not simultaneous use, with cross-sectional data collected from Canadian secondary school students (Grades 7 to 12). Symptoms of anxiety and depression were found to be associated with both polysubstance use classes compared with no substance use (Williams et al., 2021). No difference was apparent in the percentages of males and females in the dual use class, but a higher percentage of males were in the poly-use class (Williams et al., 2021). Brière and colleagues (2011) investigated predictors of simultaneous alcohol and cannabis use among secondary school students (Grades 7 to 11) in Québec (Canada). Male sex and depressive symptoms were prospectively associated with simultaneous alcohol and cannabis use in unadjusted models, but were not significant after adjusting for all predictors assessed in Grades 7 and 8 including alcohol intoxication, cannabis use, conflict with parents, and peer substance use (Brière et al., 2011).

Some youth may use substances as a coping mechanism (Wills & Shiffman, 1985). Adolescents participating in recent qualitative research reported vaping to relieve stress and anxiety, and to cope in general (Health Canada, 2020; Kong et al., 2021). Similarly, in a recent quantitative study 37.2% of Californian adolescents reported vaping to relax or relieve stress and anxiety (Donaldson et al., 2022). However, the extent to which youth identify vaping nicotine as a coping mechanism, and whether this differs by sex, has not been previously reported.

The objectives of this longitudinal study were to examine: (a) the associations between adolescent vaping at Wave 1 (2017/18; ages 14 to 17 years) and continued or new onset use of alcohol, cannabis, and/or cigarettes at Wave 2 (2019; ages 15 to 20 years), and whether the results varied by sex; (b) the associations between adolescent vaping at Wave 1 and concurrent (past-year) and simultaneous polysubstance use at Wave 2, and whether the results varied by sex; (c) factors at Wave 1 (i.e., sex, self-reported mental health disorder, history of childhood adversity, and history of peer victimization) associated with concurrent (past year) and simultaneous polysubstance use at Wave 2; and (d) the prevalence of adolescents and emerging adults who report vaping nicotine as a coping mechanism at Wave 2, and whether the results varied by sex.

Methods

Study Design and Participants

The Well-being and Experiences Study (The WE Study) is a multi-wave, longitudinal and intergenerational study conducted in Manitoba, Canada. Adolescents aged 14 to 17 years and a person-most-knowledgeable about the adolescent (98% parents; 2% other caregivers) were recruited between July 2017 and October 2018 via random digit dialing (21%), referrals (40.6%), and community advertisements (38.4%). During recruitment, demographic characteristics were monitored to ensure the adolescent sample reflected the population from which it was drawn (Afifi et al., 2020a, b). The Wave 1 sample included 1,000 parent/caregiver-adolescent dyads. Parents/caregivers and adolescents completed separate self-administered questionnaires in private rooms at a research facility. In 2019, the adolescent participants were recontacted to participate in Wave 2 (retention = 75%). The Wave 2 questionnaire was self-administered electronically via phone, tablet, or computer. Participants were aged 15 to 20 years at Wave 2 (n = 756). Participants at Wave 2 did not differ from Wave 1 based on sex or age; however, at Wave 2 more participants identified as white and had a higher household income. Some differences were also detected related to history of childhood adversity: fewer Wave 2 participants previously reported a history of household substance use problems, parental separation or divorce, contact with a child protective organization (CPO) or foster care, and poverty (proxy). All participants provided their informed consent. The WE Study received ethics approval from the University of Manitoba Health Research Ethics Board. The present study is a secondary data analysis that has drawn data from the WE Study.

Measures

Vaping (Wave 1-Wave 2). Past-30-day vaping was assessed at Wave 1 (“During the past 30 days, on about how many days did you use an electronic vapour product [such as e-cigarettes, e-cigars, vape pipes, vaping pens]?”). The seven ordinal response categories were dichotomized (“0 days” = 0; “1 or 2 days” to “All 30 days” = 1). Past-year vaping nicotine was assessed at Wave 2 (“In the past 12 months, have you used an electronic vapour product (such as e-cigarettes, e-cigars, vape pipes, vaping pens) for nicotine?”). Response options were “yes” or “no.”

Alcohol (Wave 1-Wave 2). Lifetime alcohol consumption was assessed at Wave 1. Responses of “never drank alcohol in lifetime” and “I had a sip of alcohol to see what it’s like” were coded “no.” All other responses, including “drank, but not in the past 12 months” and ordinal responses ranging from “once a month or less” to “almost every day, 6 or 7 times a week,” were coded “yes.” Past-year alcohol consumption was assessed at Wave 2 (“In the past 12 months, did you drink alcohol?”). Response options were “no,” “yes, but only once,” “yes, but only a few times,” and “yes, on a regular basis” and dichotomized as “yes” versus “no.” New onset or continued use of alcohol at Wave 2 was coded by combining the Wave 1 and Wave 2 data.

Cannabis (Wave 1-Wave 2). Past-year cannabis use was assessed at Wave 1 (“In the past 12 months, how many times have you used marijuana/hashish (e.g., pot, weed)?”). A response of “never” was coded “no” and responses of “1 to 2 times” to “10 times or more” were coded “yes.” Past-year cannabis use was assessed at Wave 2 (“In the past 12 months, have you used marijuana/cannabis in any form to get high (e.g., edibles, sprays, vaping, smoking, oils, etc.)?”). Response options were “yes” or “no.” New onset or continued use of cannabis at Wave 2 was coded by combining the Wave 1 and Wave 2 data.

Cigarettes (Wave 1-Wave 2). Lifetime cigarette smoking was assessed at Wave 1 (“Have you ever tried smoking a cigarette, even just a few puffs?”) with “yes” or “no” response options. Past-year cigarette smoking was assessed at Wave 2 (“In the past 12 months, have you smoked a cigarette?”). Response options were “no,” “yes, but only once,” “yes, but only a few times,” and “yes, on a regular basis” and dichotomized as “yes” versus “no.” New onset or continued use of cigarettes at Wave 2 was coded by combining the Wave 1 and Wave 2 data.

Polysubstance use (Wave 2). Concurrent polysubstance use combined the past-year measures of alcohol, cannabis, cigarettes, and vaping nicotine assessed at Wave 2 and was coded into three categories: “no polysubstance use,” “two substances,” and “three or four substances.” Due to low cell sizes, counts of three or four were combined. Simultaneous polysubstance use was assessed with the question: “Have you ever used any of the following substances (alcohol, nicotine, marijuana/cannabis) together at the same time?” Response options were: “never used any substances” and “never used more than one substance at a time” (recoded to “no polysubstance use”); “alcohol and nicotine (smoking or vaping nicotine)”; “alcohol and marijuana/cannabis”; “marijuana/cannabis and nicotine (smoking or vaping nicotine)”; and “alcohol, marijuana/cannabis, and nicotine (smoking or vaping nicotine).”

Vape nicotine to cope (Wave 2). Participants were asked “When you feel stressed or have negative emotions what do you do to cope?” and instructed to mark all that apply. Those who responded “vape nicotine” were coded “yes.”

Mental health disorder (Wave 1). Participants were asked “Do you currently have a long-term health condition that is expected to last or has lasted 6 months or more and has been diagnosed by a medical doctor or other health care professional?” and instructed to mark all that apply. Those who indicated any of the following were coded “yes”: depression, bipolar disorder, anxiety disorder, obsessive-compulsive disorder, post-traumatic stress disorder, eating disorder, oppositional defiant disorder, and/or conduct disorder.

Adverse Childhood Experiences (Wave 1). The ACEs that were examined included emotional abuse, emotional neglect, exposure to verbal intimate partner violence, being spanked, household substance abuse, household mental illness, parental separation/divorce, parental problems with police, parental gambling, foster care or contact with a CPO, poverty (proxy), and living in an unsafe neighbourhood. Because of mandatory reporting laws for minors, it was not possible to examine physical abuse, sexual abuse, physical neglect, or exposure to physical intimate partner violence. Detailed descriptions of these measures have been reported previously (Afifi, et al., 2020a).

Peer Victimization (Wave 1). Seven items were used to assess peer victimization (e.g., “How many times in the past 12 months has a friend, peer, kid at school, or other young person [not an adult or a sibling] done any of the following to you: pushed you, shoved you, tripped you, or spit on you.”). Each item was dichotomized (“never” to “7 to 11 times a year” = 0; “once a month” to “every day” = 1). Peer victimization was coded by combining all items. Additional details are available elsewhere (Afifi, et al., 2020a).

Covariates (Wave 1). Sociodemographic characteristics included: adolescent sex (male, female), adolescent age (14 to 17 years), parent-reported household income ($49,999 or less; $50,000 to $99,999; $100,000 to $149,999; $150,000 or more; no response), and parent-reported marital status (married or common-law; separated, divorced, or widowed; never married).

Data Analysis

Descriptive statistics for sociodemographic characteristics, risk factors, and substance use history at Wave 1 were computed for the total sample and by adolescent vaping at Wave 1. Differences were tested with logistic regression analysis. The prevalence of Wave 2 substance use was computed for the total sample and by adolescent vaping at Wave 1. Multinomial logistic regression analysis was conducted to estimate the associations between adolescent vaping (Wave 1) and new onset or continued use of alcohol, cannabis, and cigarettes, as well as past-year polysubstance use and lifetime simultaneous polysubstance use. Sex differences were examined with interaction terms. Multinomial logistic regression analysis was conducted to examine the factors associated with past-year concurrent and lifetime simultaneous polysubstance use. Models were first unadjusted then adjusted for sociodemographic characteristics. The percentage of Wave 2 respondents who reported vaping nicotine and doing so to cope was computed; sex differences were tested with chi-square analysis.

Results

The prevalence of adolescent vaping at Wave 1 was 26.6%. Adolescent vaping differed by age, but not by sex, household income, or parental marital status (Table 1). Histories of mental health disorder, emotional abuse, exposure to verbal IPV, household substance use, household mental illness, parental gambling, and peer victimization were associated with increased odds of Wave 1 vaping (odds ratio [OR] range: 1.46–2.57, p ≤ .05; Table 1). Alcohol, cannabis, and cigarette use reported at Wave 1 were also associated with increased odds of Wave 1 vaping (OR range: 11.86–14.42, p ≤ .001; Table 1).

Table 1 Sociodemographic characteristics, risk factors, and substance use in the total sample and by adolescent vaping (Wave 1)
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Wave 1 vaping was associated with greater relative risk of continued alcohol, cannabis, and cigarette use at Wave 2 (adjusted relative risk ratio [aRRR] range: 12.92–19.39, p ≤ .001) and new onset use of cannabis (aRRR = 6.04, p ≤ .001) and cigarettes (aRRR = 3.66, p ≤ .001), but not new onset use of alcohol (Table 2). Wave 1 vaping was associated with concurrent past-year polysubstance use (two substances: aRRR = 3.14, p ≤ .001; three or four substances: aRRR = 19.71, p ≤ .001) and simultaneous polysubstance use for all combinations of alcohol, nicotine (smoking or vaping), and cannabis (aRRR range: 5.58–24.25, p ≤ .001; Table 2).

Table 2 Prevalence and associations between adolescent vaping (Wave 1) and continued or new onset substance use and polysubstance use (Wave 2)
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Testing for sex differences, a significant interaction term between adolescent sex and Wave 1 vaping was observed for any new onset use of alcohol, cannabis, or cigarettes at Wave 2 (p = .016; Table 2). Post-hoc sex-stratified models were examined. Among females, adolescent vaping was associated with lower relative risk of any new onset use of alcohol, cannabis, or cigarettes at Wave 2 (aRRR = 0.22, p = .034), but the association was non-significant among males (aRRR = 1.70, p = .293). No other interaction terms were significant. Because the interaction term for new onset alcohol use approached significance (p = .065; Table 2), post-hoc sex-stratified models were examined and found to follow a similar trend (females: aRRR = 0.44, p = .142; males: aRRR = 1.53, p = .353).

Polysubstance use was prevalent with nearly half the sample (46.7%) reporting concurrent use of more than one substance in the past year and one-third (33.6%) reporting simultaneous polysubstance use. Those with a history of mental health disorder, childhood adversity (emotional abuse, emotional neglect, exposure to verbal IPV, household substance use, household mental illness, parental separation/divorce, parental gambling [unadjusted model only], foster care or contact with CPO, and living in an unsafe neighbourhood), and peer victimization were more likely to use three or four substances in the past year concurrently compared with no polysubstance use (aRRR range: 1.76–2.86, p ≤ .05; Table 3).

Table 3 Factors (Wave 1) associated with past-year polysubstance use (Wave 2)
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Histories of mental health disorder, emotional abuse, emotional neglect, household mental illness, parental separation/divorce, parental problems with police, parental gambling, and foster care or contact with CPO (aRRR range: 1.99–3.11, p ≤ .05), as well as exposure to verbal IPV (RRR = 1.72, p ≤ .05) and household substance use (RRR = 1.89, p ≤ .05) in unadjusted models only, were associated with increased relative risk of simultaneously using alcohol, cannabis, and nicotine compared with no polysubstance use (Table 4).

Table 4 Factors (Wave 1) associated with lifetime simultaneous polysubstance use (Wave 2)
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Among adolescents and emerging adults who reported vaping nicotine at Wave 2, 28.4% reported that they vape nicotine to cope with stress or negative emotions, including 33.6% of males and 24.2% of females (X2(1) = 3.09, p = .079).

Discussion

Adolescent vaping has been associated with adverse health effects and the use of other substances. The current study provides new evidence in a Canadian community-based sample of older adolescents and emerging adults (aged 15–20 years) that adolescent vaping was prospectively associated with: (a) continued use of alcohol, cannabis, and cigarettes; (b) new onset use of cannabis and cigarettes; (c) past-year polysubstance use; and (d) simultaneous polysubstance use. Prior research has shown adolescent vaping to be associated with incident cannabis and cigarette use (Bentivegna et al., 2021; Lozano et al., 2021; Seidel et al., 2022; Soneji et al., 2017; Staff et al., 2022), but longitudinal Canadian studies are lacking. Similar to a recent study conducted among a sample of emerging adults (e-cigarette use assessed at age 18; Evans-Polce et al., 2020), we found that adolescent vaping was not associated with new onset alcohol use. Although, this relationship along with bidirectional associations between e-cigarette use and alcohol use among adolescents has been noted in previous research (Lozano et al., 2021).

Owing to differences in measurement, the prevalence of concurrent polysubstance use in this study (46.7%) is not directly comparable to estimates reported in similar samples. For example, according to Zuckermann and colleagues (2020), 18% of Canadian high school students reported concurrent use of past-year alcohol binge drinking, past-year cannabis use, past-month cigarette smoking, past-month e-cigarette use, and/or past-year opioid use. Furthermore, because of a lack of relevant research, it is unclear how the prevalence of simultaneous polysubstance use (33.6%) reported in this analysis compares with that of other populations.

Adolescents who reported vaping at Wave 1 had increased risk of using multiple substances over time, including alcohol, cannabis, cigarettes, and/or vaping nicotine. Notably, adolescent vaping was associated with a 19-fold increase in the risk of using three or four of these substances concurrently. It is possible that the health risks of vaping may be greater with polysubstance use. For instance, concurrent use of cigarettes and e-cigarettes among adults has been reported to increase the risk of cardiopulmonary symptoms and conditions (Wang et al., 2018). Research on the health risks of vaping and concurrent polysubstance use is needed.

To our knowledge, this study is the first to demonstrate that adolescent vaping was associated with simultaneously using all combinations of alcohol, cannabis, and nicotine (smoking or vaping), including a 21-fold increase in the risk of using all three together. There may be several reasons for simultaneous polysubstance use including to enhance or offset the effects of a substance. Participants in a recent qualitative study reported that “vaping improves the effects of cannabis and of other recreational drugs and that the head rush they got from vaping tended to be better when they had consumed alcohol” (Health Canada, 2020, p. 12). However, mixing substances may exacerbate the risk of harm. For example, simultaneous use of nicotine and alcohol may increase craving for and consumption of both substances, while decreasing the perceived effects of alcohol such as feeling intoxicated (Verplaetse & McKee, 2017).

Interventions to prevent the initiation of vaping and to help adolescents quit should be prioritized. Such efforts may also prevent or delay the use of other substances and polysubstance use. Importantly, other research has also indicated that vaping is emerging as an increased avenue for cannabis consumption among adolescents (Tai et al., 2021). As well, reducing substance use and polysubstance use is important since some studies have shown a relationship between cannabis use and dissociative and psychotic symptoms (Ricci et al., 2021, 2023). Several e-cigarette interventions have been developed, including school- and community-based programs (O’Connor et al., 2019); evaluation of the efficacy of these strategies is needed.

Overall, evidence of sex differences in these associations was lacking, which suggests that interventions may not need to be tailored to males and females separately. While it is possible that adolescent vaping is associated with a lower risk of initiating alcohol use among females but not males, the findings indicate that adolescent vaping was associated with continued use of alcohol over time for both sexes. Also, sex was not clearly associated with polysubstance use. Compared with males, females were more likely to have used two substances in the past year (unadjusted model only), but not three or four. Females were more likely than males to simultaneously use alcohol and cannabis (unadjusted model only), but no differences between males and females emerged for combinations including nicotine. Further investigation is warranted.

Risk factors identified for concurrent and simultaneous polysubstance use included: adolescent mental health disorder, a history of ACEs (emotional abuse, emotional neglect, exposure to verbal IPV, household substance use, household mental illness, parental separation or divorce, parental problems with police, parental gambling, foster care or contact with CPO, and living in an unsafe neighbourhood), and for concurrent, but not simultaneous use, peer victimization. Some risk factors had large effect sizes in the adjusted model, although were non-significant. It is possible that these factors (e.g., exposure to verbal IPV, household substance use, parental problems with police, parental gambling, unsafe neighbourhood) were underpowered resulting in a Type II error. Most of these risk factors were also identified cross-sectionally for adolescent vaping at Wave 1. These trends suggest that strategies to prevent adolescent vaping and concurrent and simultaneous polysubstance use should take into consideration histories of mental health disorder, childhood adversity, and peer victimization. Such strategies must include both primary prevention of mental illness, adversity, and peer victimization as well as selective substance use prevention interventions. The Rise Above program is one intervention aimed at preventing e-cigarette and other substance use for adolescents exposed to ACEs, and is currently being evaluated with a pilot randomized controlled trial (Shin, 2021).

The current study also identifies vaping nicotine as a coping mechanism for a sizable number of Wave 2 respondents who reported vaping, including one-third of males and one-quarter of females who were vaping. Coping motives for substance use were identified in a recent systematic review as key targets for interventions designed to prevent substance use among youth exposed to adversity (Grummitt et al., 2021). Efforts are needed to provide adolescents and emerging adults with alternative positive strategies for coping with stress and negative emotions.

The results of this analysis should be considered in the context of several limitations. The types of substances used while vaping at Wave 1 was not specified; it is possible that adolescents vaped without nicotine or with cannabis. The wording of the alcohol, cannabis, and cigarette use measures also differed between timepoints, which may contribute to differences in reporting and possibly introduce some error in the findings. In the concurrent polysubstance use measurement, both vaping nicotine and smoking cigarettes involve the use of nicotine. Substance use outcomes had to be dichotomized to gain adequate statistical power to compute the models. Future work using a large sample size is needed to examine these relationships using more detailed frequency of use data. It was not possible to assess all ACEs due to mandatory reporting rules for respondents less than 18 years, which means ACEs will be underreported in this study and may have led to more conservative estimates. The data were self-reported and may be subject to recall and social desirability bias. However, it is important to note that the time for recall is shorter for adolescents and previous research has found that retrospective recall of adversity during childhood is a valid method in research (Hardt & Rutter, 2004). The baseline WE Study sample was similar to the adolescent population, but not representative. Although 75% of the baseline adolescent sample was retained at Wave 2, differences in sample characteristics at Wave 2 suggest non-random attrition. A small sample size meant that sex, but not gender, was examined. Few sex differences were noted, but important gender differences may exist.

Adolescent vaping is an important risk factor for the subsequent use of alcohol, cannabis, and cigarettes, and may increase the risk of using multiple substances both concurrently and simultaneously. Interventions to prevent vaping initiation and to help with vaping cessation should be prioritized for this age group. Adolescents and emerging adults may also need alternative coping strategies when they feel stressed or have negative emotions. Furthermore, the findings from this study indicate that upstream efforts to prevent adolescent vaping and later polysubstance use should include primary prevention of childhood adversity as well as selective interventions for those who have a mental health disorder or have experienced ACEs or peer victimization.