High School Students' Use of Electronic Cigarettes to Vaporize Cannabis

Vaping and cardiac disease

Tobacco cigarette smoking is the most prevalent reversible risk factor for cardiovascular disease in the USA. Electronic cigarettes, invented as an alternative nicotine source for smokers unable or unwilling to stop smoking, have gained skyrocketing popularity, but their cardiovascular risk remains uncertain. Although data recently analysed in a Cochran report do support their superior effectiveness to other forms of nicotine replacement therapies for smoking cessation, electronic cigarettes are also frequently used by non-smokers-especially high school students. There are no long-term outcome studies on the cardiovascular risk of vaping electronic cigarettes, but the effects of electronic cigarettes on known risk factors for cardiovascular disease, including neurohumoural activation, oxidative stress and inflammation, endothelial function and thrombosis, have been studied. In this review, we summarise evidence in humans that supports the notion that while electronic cigarettes may be less harmful than traditional cigarettes, they are not harmless. Additionally, the increasing popularity of vaping marijuana with its unknown cardiovascular risks as well as the outbreak in 2019 of EVALI (electronic cigarette, or vaping, product use-associated lung injury) related to bootlegged vaping products raise further concerns. Before physicians can confidently advise their smoking patients about the role of electronic cigarettes as a means of smoking cessation to lower cardiovascular risk, improved regulation and quality control is necessary.

Effects of Δ⁹-tetrahydrocannabinol (THC) vapor inhalation in Sprague-Dawley and Wistar rats

An inhalation system based on e-cigarette technology produces hypothermic and antinociceptive effects of Δ⁹-tetrahydrocannabinol (THC) in rats. Indirect comparison of some prior investigations suggested differential impact of inhaled THC between Wistar (WI) and Sprague-Dawley (SD) rats; thus, this study was conducted to directly compare the strains across inhaled and injected routes of administration. Groups (N = 8 per strain) of age-matched male SD and WI rats were prepared with radiotelemetry devices to measure temperature and then exposed to vapor from the propylene glycol (PG) vehicle or THC (25-200 mg/mL of PG) for 30 or 40 min. Additional studies evaluated effects of THC inhalation on plasma THC (50-200 mg/mL) and nociception (100-200 mg/mL) as well as the thermoregulatory effect of intraperitoneal injection of THC (5-30 mg/kg). Hypothermic effects of THC were more pronounced in SD rats, where plasma levels of THC were identical across strains, under either fixed inhalation conditions or injection of a mg/kg equivalent dose. Strain differences in hypothermia were largest after i.p. injection of THC, with SD rats exhibiting dose-dependent temperature reduction after 5 or 10 mg/kg, i.p. and the WI rats only exhibiting significant hypothermia after 20 mg/kg, i.p. The antinociceptive effects of inhaled THC (100, 200 mg/mL) did not differ significantly across the strains. These studies confirm an insensitivity of WI rats, compared with SD rats, to hypothermia induced by THC following inhalation conditions that produced identical plasma THC and antinociception. Thus, quantitative, albeit not qualitative, strain differences may be obtained when studying thermoregulatory effects of THC. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Electronic Vapor Product Use and Violence Victimization Among a Nationally Representative Sample of Adolescents

PURPOSE

We examined associations between electronic vapor product use (vaping) and violence victimization (adolescent relationship abuse (ARA), youth violence, bullying, and experiencing all three types of violence).

METHODS

Data were drawn from the 2017 National Youth Risk Behavioral Survey. Logistic regression examined associations between vaping and violence victimization, adjusting for sex, age, race, identification as a sexual minority, and use of other substances.

RESULTS

After adjusting for demographic characteristics, vaping was significantly and positively associated with ARA, youth violence, bullying, and experiencing all three types of violence (ARA: adjusted odds ratio (aOR) 3.0, 95% CI: 2.5-3.5; youth violence: aOR 3.0, CI: 2.4-3.6; bullying: aOR 1.5, CI: 1.4-1.7; all three types of violence: 10, CI: 6.3, 15.8). When use of other substances was added into the model, these associations attenuated, and, for bullying, lost significance.

CONCLUSIONS

Vaping is associated with increased violence victimization, particularly for youth experiencing ARA, youth violence, and polyvictimization. Further longitudinal studies are needed to determine directionality of these associations and guide prevention efforts.

E-cigarettes: A novel therapy or a looming catastrophe

Electronic cigarettes (e-cigarettes) were originally developed in 2003 as healthier alternatives to conventional tobacco cigarettes. Their popularity has since significantly increased and both users and nonusers are exposed to their aerosol and product constituents. Although some evidence suggests that e-cigarette use may facilitate smoking cessation, definitive data are lacking and e-cigarettes are not approved by the Food and Drug Administration as a cessation aid. While e-cigarette aerosol contains fewer toxins than conventional cigarette smoke, studies evaluating whether e-cigarettes are less harmful are inconclusive. The health impact of e-cigarettes for both users and nonusers cannot be determined with currently available data, and there are both environmental concerns and issues regarding nonuser exposure. Most of the currently available data related to the health effects of e-cigarettes do not evaluate their effects on the general population and evidence regarding the systemic health effects of e-cigarettes is limited. In addition, there has been a recent rise in vaping-related lung injuries. Therefore, the detrimental effects of e-cigarette use should be further investigated, and every effort should be made to increase public awareness of the harmful effects of e-cigarettes.

School-based e-cigarette education in Alabama: Impact on knowledge of e-cigarettes, perceptions and intent to try

BACKGROUND AND OBJECTIVES

Educational programs are needed to combat the sharp rise in adolescent e-cigarette use. We assessed adolescent knowledge about e-cigarettes, perceptions of harmfulness and addictiveness and intent to try e-cigarettes before and after an e-cigarette educational session.

METHODS

We conducted a one-group pre- and post-test study among middle and high school students in Alabama in 2019. The intervention included a 30-minute educational session based on the Stanford Tobacco Prevention Toolkit on e-cigarette types, contents, marketing and advertising, health effects and nicotine addiction. McNemar tests of paired proportions and multi-level, mixed-effects logistic regression models were used to analyze intervention effects.

RESULTS

Surveys were completed by 2,889 middle and high school students. The intervention was associated with significantly increased knowledge about e-cigarettes and perceptions that e-cigarettes are harmful and addictive, and with significantly lower intent to try e-cigarettes. At pre-test, middle school students had lower knowledge, believed that e-cigarettes were not as addictive and showed higher intent to try both e-cigarettes and cigarettes compared to high school students. Groups that were associated with lower perceived harmfulness and addictiveness were: ever-users of e-cigarettes, ever-users of both e-cigarettes and cigarettes and prior users of mint/menthol flavored e-cigarettes.

CONCLUSIONS

A school-based educational session was significantly associated with improved adolescent knowledge about e-cigarettes, increased the perceived harmfulness and addictiveness of e-cigarettes, and reduced intent to try e-cigarettes. E-cigarette education should be prioritized for middle school students due to lower levels of knowledge and higher intent to try tobacco compared to high school students.

Characterizing the predictive validity of measures of susceptibility to future use of combustible, vaporized and edible cannabis products in adolescent never-users

BACKGROUND AND AIMS

The construct of susceptibility to substance use initiation (i.e. cognitive proclivity to future use) is critical for prevention efforts in adolescent populations. This study aimed to provide empirical evidence for the validity of the susceptibility construct for different cannabis products (i.e. combustible, edible or vaporized cannabis), and evaluate whether susceptibility measures are predictive of subsequent initiation.

DESIGN

Prospective cohort study including baseline data (Spring 2015) and four follow-up surveys administered every 6 months through Spring 2017.

SETTING

Ten schools in the Los Angeles, California metropolitan area.

PARTICIPANTS

Adolescents [n = 2100; mean age = 16.1; standard deviation (SD) = 0.41; 54% female] who reported never having used any cannabis product at baseline.

MEASUREMENTS

We assessed five indices of a susceptibility to use cannabis composite index at baseline, adapted from a validated tobacco use index (intention to use, willingness, curiosity and positive/negative cannabis use outcome expectancies, with four response categories, definitely not [1] to definitely yes [4]), by cannabis product (combustible, edible or vaporized). A composite index was created for each product by averaging responses across the five susceptibility items. Subsequent initiation of use of each cannabis product was assessed at each follow-up wave.

FINDINGS

Factorial validity for unidimensionality for each five-item index (by product) was confirmed. The composite index for susceptibility to cannabis use was greatest for combustible (mean = 1.44; SD = 0.58), moderate for edible (mean = 1.37; SD = 0.53) and lowest for vaporized cannabis (mean = 1.30; SD = 0.44). The associations of each composite susceptibility index with subsequent initiation of that product and each of the other cannabis products over follow-up (i.e. cross-product associations) were statistically significant, with hazard ratios ranging from 2.30 to 2.80 across 24 months of follow-up (all Ps < 0.05).

CONCLUSIONS

A five-item susceptibility to cannabis use composite index (by product) appears to be useful for characterizing and predicting youth at risk for cannabis use initiation across a spectrum of cannabis products.

Availability of substances for use in personal vaporisers on three online cryptomarkets

BACKGROUND

Personal vaporisers are gaining popularity as an alternative route of administration for a range of substances. Online cryptomarkets are becoming increasingly popular among people who use substances due to their perceived anonymity, ease of use, and reduced risk of violence compared to traditional face-to-face dealers. We examined the diversity of substances marketed for use in a personal vaporiser on these marketplaces.

METHODS

Vaping related listings were extracted from three online cryptomarkets ('Agartha', 'Cryptonia', and 'Tochka') using The Onion Router browser. Data collection occurred between October and November 2019.

RESULTS

We identified 1929 listings from 201 unique sellers. The top product on Agartha, Cryptonia, and Tochka were vape cartridges prefilled with the e-liquid (70.4 %, 39.4 %, 52.3 % respectively). The most common substance in these products was cannabis oil (96.1 %, 82.1 %, 87.8 %), followed by synthetic cannabinoids (3.7 %, 9.7 %, 9.8 %) and psychedelic substances (0.2 %, 6.4 %, 1.2 %). Vendors were primarily from the USA. Many products offered worldwide shipping (96.3 %, 42.4 %, 51.2 %).

CONCLUSION

Vaping products listed on online cryptomarkets in 2019 primarily contained cannabis oils. Future studies should continue to examine cryptomarkets to identify emerging trends of substances that can be used in personal vaporisers.

Assessment of Nicotine and Cannabis Vaping and Respiratory Symptoms in Young Adults

IMPORTANCE

Rates of e-cigarette use (ie, nicotine vaping) and cannabis vaping continue to increase among youth and young adults. However, the association of nicotine and cannabis vaping with independent respiratory health outcomes has not been well studied.

OBJECTIVE

To investigate associations of nicotine and cannabis vaping with bronchitic symptoms, wheeze, and shortness of breath.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional survey data on self-reported lifetime, 6-month, and 30-day vaping from 2553 young adults recruited from high schools in Southern California were collected from June 2018 to October 2019. Of these participants, 94% provided data for shortness of breath and wheeze, and 86% provided data for chronic bronchitis.

MAIN OUTCOMES AND MEASURES

Self-reported nicotine and cannabis vaping were measured on a Likert-type scale using the following responses: (1) never used, (2) lifetime but no past 6-month use, (3) past 6-month use but no use in the past 30 days, (4) use on 1 or 2 of the past 30 days, and (5) use on 3 or more of the past 30 days. Three respiratory health outcomes were assessed separately on the basis of self-reported symptoms: bronchitic symptoms in the previous 12 months (ie, daily cough for 3 months in a row, congestion or phlegm other than with a cold, and/or bronchitis), wheeze in the previous 12 months, and shortness of breath when hurrying on level ground or walking up a slight hill.

RESULTS

Of 2553 participants in the analytic sample (mean [SD] age, 19.3 [0.79] years; 1477 [57.9%] female individuals), 1095 of 2553 young adults (42.9%) reported vaping nicotine and 939 of 2553 (38.4%) reported vaping cannabis. Compared with those who never vaped cannabis, individuals who vaped cannabis in their lifetime but not in the past 60 months (204 of 2553 [8.4%]; adjusted odds ratio [aOR], 1.83 [95% CI, 1.08-3.10]), in the past 6 months but not in the last 30 days (490 of 2443 [20.1%]; aOR, 1.58 [95% CI, 1.02-2.46]), 1-2 days in the past 30 days (90 of 2443 [3.7%]; aOR, 2.83 [95% CI, 1.46-5.50]), and 3 or more days in the past 30 days (155 of 2443 [6.3%]; aOR, 2.14 [95% CI, 1.16-3.92]) had significantly higher odds of chronic bronchitic symptoms after adjusting for nicotine vaping, cigarette smoking, cannabis smoking, and sociodemographic characteristics. Cannabis vaping 3 or more times in the last 30 days was also associated with increased odds of wheeze (aOR, 2.27 [95% CI, 1.17-4.37]). Associations of cannabis vaping with shortness of breath and nicotine vaping with any respiratory health outcome were not statistically significant in fully adjusted models.

CONCLUSIONS AND RELEVANCE

Findings of this cross-sectional study suggest that cannabis vaping is associated with increased risk of bronchitic symptoms and wheeze in young adults. Further research is needed to understand the temporality of the association and the mechanisms underlying the difference between nicotine and cannabis vaping in the risk of bronchitic symptoms and wheeze.

Vaping while high: Factors associated with vaping marijuana among youth in the United States

INTRODUCTION

The use of e-cigarette and other vaping devices have become popular among youth in US. In addition to nicotine, vaping devices can be used to vaporize marijuana. However, factors associated with vaping marijuana among youth remain unexplored. This study examined the rates of vaping marijuana and its correlates among youth in the US.

METHODS

We conducted a cross-sectional analysis of survey data from the 2018 National Youth Tobacco Survey of middle-and high-schoolers who provided information regarding ever use of vaping devices to vape marijuana (n = 10,680). Multivariable regression model was conducted to assess factors associated with vaping marijuana.

RESULTS

Overall, 26.2 % of participants reported ever vaping marijuana. High-schoolers [vs middle-schoolers; aOR = 2.16,95 %CI:1.76-2.67], Hispanics [vs Whites; aOR = 2.30,95 %CI:1.90-2.80], and Blacks [vs Whites; aOR = 1.42,95 %CI:1.04-1.92] were more likely to ever vape marijuana. Those who perceived e-cigarette as equally addictive to cigarettes, were less likely to ever vape marijuana [aOR = 0.79, 95 %CI:0.65-0.97]. In addition, those who reported ever trying cigarettes [aOR = 1.63,95 %CI:1.29-2.06], cigars [aOR = 2.62, 95 %CI:2.08-3.30], or hookah [aOR = 2.88,95 %CI:2.14-3.89] were more likely to ever vape marijuana. Lifetime frequency of e-cigarette use was associated with greater odds of ever vaping marijuana (p-values <0.001).

CONCLUSION

Large numbers of youth in the US have ever vaped marijuana. Our findings indicate that sociodemographic characteristics, tobacco product use, frequency of e-cigarette use are important factors associated with vaping marijuana. Tobacco control campaigns targeted at curbing the use of e-cigarette and other vaping devices among youth in the US should be extended to address vaping substances other than nicotine such as marijuana.

Psychological distress and substance use among young adults with comorbid asthma and obesity

This study examined psychosocial distress and substance use in young adults with asthma (A), obesity (O), comorbid asthma and obesity (AO), or neither (controls). Participants: Eight hundred eighty-one young adults were included in the A, O, AO, or control group. Methods: ANCOVA and logistic regression analyses were performed to compare responses to screeners for psychological distress and substance use among the four groups. Results: Levels of depressive symptoms, worry, nonsuicidal self-injury, emotion dysregulation, and chronic pain symptoms differed across groups, with the A and AO groups showing greater psychological distress than the O and control groups. The AO group exhibited the highest levels of cigarette and smokeless tobacco use, while the O group exhibited the least frequent binge drinking behaviors. Conclusions: Individuals with asthma or comorbid asthma and obesity appear to experience the poorest psychosocial functioning and highest use of tobacco products. Potential mechanisms and implications of these relationships are discussed.

Adolescent Marijuana Use and Related Risk Behaviors, National Findings From 2015 to 2017

INTRODUCTION

As policies legalizing nonmedical marijuana have increased in states, understanding the implications of marijuana use among adolescents is increasingly important. This study uses nationally representative data to assess behavioral risk factors among students with different patterns of marijuana use.

METHODS

Data from the 2015 and 2017 Youth Risk Behavior Surveys, cross-sectional surveys conducted among a nationally representative sample of students in Grades 9-12 (n=30,389), were used to examine the association between self-reported current marijuana use status and self-report of 30 risk behaviors across 3 domains: substance use, injury/violence, and sexual health. Among current marijuana users, authors assessed differences between established (≥100 lifetime uses) and nonestablished (<100 uses) users. Multivariable models were used to calculate adjusted prevalence ratios. Data were analyzed in 2019.

RESULTS

Current marijuana users (regardless of use pattern) had a significantly greater likelihood of engaging in 27 of the 30 behaviors assessed across the 3 domains than the noncurrent users. Those with established use patterns (versus nonestablished) had a greater risk of lifetime use of most other substances (licit and illicit, including tobacco, alcohol, heroin, misuse of opioids), some injury/violence behaviors (including driving while using marijuana and suicide ideation and attempt), and sexual risk behaviors.

CONCLUSIONS

Both established and nonestablished patterns of adolescent marijuana use are associated with a number of other risky behaviors. In addition to interventions focused on preventing youth initiation of marijuana, clinicians and public health professionals should consider interventions to help adolescents who have nonestablished use patterns to avoid continued, established use.

A vapor exposure method for delivering heroin alters nociception, body temperature and spontaneous activity in female and male rats

BACKGROUND

The ongoing crisis related to non-medical use of opioids makes it of continued importance to understand the risk factors for opioid addiction, the behavioral and neurobiological consequences of opioid exposure and to seek potential avenues for therapy. Pre-clinical rodent models have been critical to advancing understanding of opioid consequences for decades, but have been mostly limited to drug delivery by injection or by oral dosing. Inhalation, a significant route for many human users, has not been as well-established.

METHOD

We adapted an e-cigarette based exposure system, previously shown efficacious for delivery of other drugs to rats, to deliver heroin vapor. Effectsin vivo were assessed in male and female Sprague-Dawley rats using a warm-water assay for anti-nociception and an implanted radiotelemetry system for evaluating changes in body temperature and spontaneous activity rate.

RESULTS

Inhalation of vapor created by heroin 100 mg/mL in the propylene glycol (PG) vehicle significantly slowed tail-withdrawal from a 52 °C water bath, bi-phasically altered activity, and increased temperature in male and female rats. Inhalation of heroin 50 mg/mL for 15 min produced significant effects, as the lower bound on efficacy, whereas inhalation of heroin 100 mg/mL for 30 min produced robust effects across all endpoints and groups.

CONCLUSIONS

This work shows that e-cigarette devices deliver psychoactive doses of heroin to rats, using concentrations of ∼50-100 mg/mL and inhalation durations of 15-30 min. This technique may be useful to assess the health consequences of inhaled heroin and other opioid drugs.

E-cigarette use and concurrent risk behaviors among adolescents

PURPOSE

Although electronic cigarette (e-cigarette) use is on the rise among adolescents, its relationship with risk behaviors is unclear. This study aimed to examine whether e-cigarette use was related to other risk behaviors and whether age and sex play a role in those associations.

METHODS

Data from the 2017 Youth Risk Behavior Surveillance System was used. Weighted logistic regression analysis was conducted to examine the relationships among variables of interest.

FUNDINGS

The results showed that e-cigarette users, compared to nonusers, had higher odds of using other types of substances, as well as being involved in other risk behaviors including driving-related behaviors, sexual activity-related behaviors, and violence-related behaviors. Furthermore, some of these relationships are moderated by age and sex.

DISCUSSION

Our findings suggest that e-cigarette use is linked to other risk behaviors among adolescents. Policy makers and educators should address multiple risk behaviors as part of comprehensive tobacco-free policies and youth substance use prevention programs.

Trajectories of Nicotine and Cannabis Vaping and Polyuse From Adolescence to Young Adulthood

IMPORTANCE

Little is known about cannabis vaping trajectories across adolescence and young adulthood or the co-occurrence with nicotine vaping.

OBJECTIVE

To evaluate nicotine vaping and cannabis vaping trajectories from late adolescence to young adulthood (≥18 years of age) and the extent of polysubstance vaping.

DESIGN, SETTING, AND PARTICIPANTS

In this prospective cohort study, 5 surveys (including information on substance vaped) were completed at 10 high schools in the Los Angeles, California, metro area. Students were surveyed at 6-month intervals from fall of 11th grade (October to December 2015; wave 5) through spring of 12th grade (March to June 2017; wave 8) and again approximately 1 to 2 years after high school (October 2018 to October 2019; wave 9).

EXPOSURES

Past 30-day nicotine and cannabis vaping frequency across 5 waves.

MAIN OUTCOMES AND MEASURES

Self-reported frequency of nicotine vaping and cannabis vaping within the past 30 days across 5 time points from late adolescence to young adulthood. Trajectories were measured with these past 30-day use frequencies at each wave. Parallel growth mixture modeling estimated conditional probabilities of polysubstance vaping.

RESULTS

The analytic sample included 3322 participants with at least 1 time point of data (mean [SD] age, 16.50 [0.42] years at baseline; 1777 [53.5%] female; 1573 [47.4%] Hispanic or Latino). Growth mixture modeling identified the 5-trajectory model as optimal for both nicotine vaping and cannabis vaping. Trajectories for nicotine and cannabis vaping were similar (nonusers: 2246 [67.6%] nicotine, 2157 [64.9%] cannabis; infrequent users: 566 [17.0%] nicotine, 608 [18.3%] cannabis; moderate users: 167 [5.0%] nicotine, 233 [7.0%] cannabis; young adult-onset frequent users: 213 [6.4%] nicotine, 190 [5.7%] cannabis; adolescent-onset escalating frequent users: 131 [3.9%] nicotine, 134 [4.0%] cannabis). Males had greater odds of belonging to the adolescent-onset escalating frequent users nicotine (adjusted odds ratio, 2.88; 95% CI, 1.58-5.23; P < .01) and cannabis (adjusted odds ratio, 1.95; 95% CI,1.03-3.66; P < .05) vaping trajectories compared with nonusers. Polysubstance vaping was common, with those in trajectories reflecting more frequent nicotine vaping (adolescent-onset escalating frequent users and young adult-onset frequent users) having a high probability of membership (85% and 93%, respectively) in a cannabis-use trajectory.

CONCLUSIONS AND RELEVANCE

In this cohort study, the prevalence and type of nicotine vaping and cannabis vaping developmental trajectories from late adolescence to young adulthood were similar. Polysubstance vaping was common from late adolescence to young adulthood, particularly among those reporting more frequent vaping use. The findings suggest that public health policy and clinical interventions should address polysubstance vaping in both adolescence and young adulthood.

School-Level Prevalence and Predictors of e-Cigarette Use in 8th, 10th, and 12th Grade U.S. Youth: Results From a National Survey (2015-2016)

PURPOSE

The aim of this study was to examine the school-level prevalence and predictors of e-cigarette use among U.S. adolescents.

METHODS

The Monitoring the Future study is an annual national cross-sectional study of secondary (middle and high) school students. This study uses 2015 and 2016 survey data from 8th, 10th, and 12th grade students (n = 38,926) attending 580 U.S. public and private secondary schools. E-cigarette use, binge drinking, cigarette smoking, marijuana use, and nonmedical prescription drug use were measured at the individual level. School-level characteristics were measured with both aggregated student-level measures (e.g., school-level e-cigarette use, school-level racial composition) and school characteristics (e.g., public vs. private, urban vs. rural).

RESULTS

The prevalence of past-month e-cigarette use varied considerably across 580 U.S. middle and high schools, ranging from 0% to 60% at individual schools (mean = 10.2%, standard deviation = 8.9%). Multivariable regression analyses indicated that past-month e-cigarette use was significantly higher at schools with a higher proportion of White students, schools that were located in the U.S. Southern and Western regions, and schools with higher prevalence of past-month cigarette smoking, after controlling for relevant individual- and school-level covariates.

CONCLUSIONS

E-cigarette use varies considerably across schools, and this study suggests that school context plays an important role in e-cigarette use. Cigarette smoking and e-cigarette use at the school level are closely linked and are important risk factors for individual-level e-cigarette use. The wide variation in prevalence of e-cigarette use highlights the need for schools to work with professionals to obtain school-level assessment rather than relying solely on state or national results to guide prevention efforts.

Predictors of JUUL, other electronic nicotine delivery systems, and combustible tobacco initiation among Texas youth

The objectives of this study were to 1) examine longitudinal predictors of JUUL and other tobacco product initiation, 2) compare these predictors across product type, and 3) describe cross-sectional characteristics of JUUL initiators, among a cohort of Texas adolescents. Analyses were also stratified to examine whether predictors of initiation differed by susceptibility to tobacco use at baseline. This study utilized data from Waves 7 and 8 (Fall 2017 and Spring 2018) of the Texas Adolescent Tobacco and Marketing Surveillance System (n = 2272). Chi-square tests and multinomial logistic regressions were conducted to examine differences in predictors of initiation. Among those who initiated at Wave 8 (n=107), 40.2% initiated JUUL, 43.9% initiated other ENDS, and 15.9% initiated other combustible tobacco. For the full sample, ever marijuana use predicted the initiation of all tobacco products (Relative Risk Ratios "RRRs" from 2.31-4.13) as compared to non-users. For non-susceptible youth, ever marijuana use significantly predicted the initiation of JUUL (RRR = 10.08, 95% CI = 2.11-48.17) and other ENDS use (RRR = 12.07, 95% CI = 2.97-49.04). Peer tobacco use predicted the initiation of JUUL (RRR = 3.06, 95% CI = 1.38-6.81) and other ENDS use (RRR = 5.36, 95% CI = 2.11-13.64) for the full sample, as well as those who were susceptible to tobacco use. For non-susceptible youth, peer tobacco use predicted the initiation of combustible tobacco use (RRR = 16.56, 95% CI = 1.56-175.84). Prominent reasons for JUUL use included curiosity, friend use, and less harmful that cigarettes. Results highlight the role of marijuana in the initiation of all tobacco products, even among low-risk youth; other predictors varied between product type. Interventions should address specific predictors to prevent youth from transitioning to tobacco use.

Explication of CB1 receptor contributions to the hypothermic effects of Δ9-tetrahydrocannabinol (THC) when delivered by vapor inhalation or parenteral injection in rats

The use of Δ⁹-tetrahydrocannabinol (THC) by inhalation using e-cigarette technology grows increasingly popular for medical and recreational purposes. This has led to development of e-cigarette based techniques to study the delivery of THC by inhalation in laboratory rodents. Inhaled THC reliably produces hypothermic and antinociceptive effects in rats, similar to effects of parenteral injection of THC. This study was conducted to determine the extent to which the hypothermic response depends on interactions with the CB₁ receptor, using pharmacological antagonist (SR141716, AM-251) approaches. Groups of rats were implanted with radiotelemetry devices capable of reporting activity and body temperature, which were assessed after THC inhalation or injection. SR141716 (4 mg/kg, i.p.) blocked or attenuated antinociceptive effects of acute THC inhalation in male and female rats. SR141716 was unable to block the initial hypothermia caused by THC inhalation, but temperature was restored to normal more quickly. Alterations in antagonist pre-treatment time, dose and the use of a rat strain with less sensitivity to THC-induced hypothermia did not change this pattern. Pre-treatment with SR141716 (4 mg/kg, i.p.) blocked hypothermia induced by i.v. THC and reversed hypothermia when administered 45 or 90 min after THC (i.p.). SR141716 and AM-251 (4 mg/kg, i.p.) sped recovery from, but did not block, hypothermia caused by vapor THC in female rats made tolerant by prior repeated THC vapor inhalation. The CB₂ antagonist AM-630, had no effect. These results suggest that hypothermia consequent to THC inhalation is induced by other mechanisms in addition to CB₁ receptor activation.

Youth marijuana use: a review of causes and consequences

The legalization of medical and recreational marijuana has raised concerns about a potential increase in the availability and illegal use of marijuana by adolescent minors. To better understand the etiology, patterns, and consequences of adolescent marijuana use, this article reviews high quality, methodologically rigorous, longitudinal studies that focus on the role of personality factors such as sensation-seeking in the etiology of use, developmental trajectories of use and the effects of chronic use, potential gateway effects of marijuana on other illicit drugs, and its role in the onset of psychiatric disorders in adolescents and young adults. Implications are discussed in terms of mechanisms that account for initial and continued use of marijuana by adolescents, how use is associated with key developmental milestones and adult role socialization, and the potential of marijuana use during adolescence in furthering later drug involvement.

Review of Health Consequences of Electronic Cigarettes and the Outbreak of Electronic Cigarette, or Vaping, Product Use-Associated Lung Injury

Electronic cigarettes (e-cigarettes) are battery-operated devices to insufflate nicotine or other psychoactive e-liquid aerosols. Despite initial claims of e-cigarettes as a nicotine-cessation device, aggressive marketing of e-cigarettes has led to an explosion in adolescents' and young adults' use over the last few years. Coupled with a lack of adequate investigation and regulation of e-cigarettes, the USA is facing an outbreak of e-cigarette, or vaping, product use-associated lung injury (EVALI) starting in mid-2019. While little long-term health hazard data are available, the components and constituents of e-cigarettes may adversely impact health. Propylene glycol and glycerin are humectants (water-retaining excipients) that generate pulmonary irritants and carcinogenic carbonyl compounds (e.g., formaldehyde, acetaldehyde, and acrolein) when heated in e-cigarettes. Metals contained in heating coils and cartridge casings may leach metals such as aluminum, chromium, iron, lead, manganese, nickel, and tin. Flavoring agents are considered safe for ingestion but lack safety data for inhalational exposures. Diacetyl, a common buttery flavoring agent, has known pulmonary toxicity with inhalational exposures leading to bronchiolitis obliterans. In 2019, clusters of lung injury associated with e-cigarette use were identified in Wisconsin and Illinois. Patients with EVALI present with a constellation of respiratory, gastrointestinal, and constitutional symptoms. Radiographically, patients have bilateral ground glass opacifications. As of February 18, 2020, the Centers for Disease Control has identified 2807 hospitalized patients diagnosed with either "confirmed" or "probable" EVALI in the US. Currently, vitamin E acetate (VEA) used as a diluent in tetrahydrocannabinol vape cartridges is implicated in EVALI. VEA cuts tetrahydrocannabinol oil without changing the appearance or viscosity. When inhaled, pulmonary tissue lacks the mechanism to metabolize and absorb VEA, which may lead to its accumulation. While most EVALI patients were hospitalized, treatment remains largely supportive, and use of corticosteroids has been associated with clinical improvement. The outbreak of EVALI highlights the need for regulation of e-cigarette devices and e-liquids. Clinicians need to be aware of the health hazards of e-cigarettes and be vigilant in asking about vaping.

Public Health Considerations for Adolescent Initiation of Electronic Cigarettes

Adolescent use of electronic cigarettes (e-cigarettes) has increased dramatically, with younger and nicotine-naive adolescents starting to use these devices and use them more frequently than combustible cigarettes. In emerging evidence, it is shown that e-cigarettes are not effective in helping adult smokers quit and that youth using e-cigarettes are at risk for becoming nicotine dependent and continuing to use as adults. Important gaps in our knowledge remain regarding the long-term health impact of e-cigarettes, effective strategies to prevent and reduce adolescent e-cigarette use, and the impact of provider screening and counseling to address this new method of nicotine use.

Smoking and use of electronic cigarettes (vaping) in relation to preterm birth and small-for-gestational-age in a 2016 U.S. national sample

Women who smoke may be motivated to switch to vaping (use electronic cigarettes, e-cigs) around pregnancy in seeking to alleviate known hazards of smoking. E-cigs typically contain nicotine but either eliminates or greatly reduces exposure to the combustion products of tobacco. We studied a U.S.-wide representative sample of 31,973 live singleton births in 2016. In the three months before pregnancy, 5029 (14%) mothers exclusively smoked tobacco ("sole smokers") and 976 (3%) used both tobacco and e-cigs ("dual-users"). Among pre-pregnancy sole smokers, 44% continued to only smoke while 1% became dual-users in late pregnancy. Logistic regression models were used to assess the adjusted odds ratios (aOR) for preterm and small-for-gestational-age (SGA) by reported smoking or vaping in late pregnancy. Compared to women who used neither product ("non-users"), late-pregnancy sole smokers had increased risks for preterm birth (aOR 1.6, 95% CI 1.2-2.0) and SGA (aOR 2.4, 95% CI 1.8-2.9), after adjusting for their pre-pregnancy smoking or vaping status and other confounders. The adjusted models also showed that late-pregnancy sole vapers had similar risk of preterm birth as non-users (aOR 1.2, 95% CI 0.5-2.7). Late-pregnancy dual-users also had similar risk of preterm birth as non-users (aOR 1.3, 95% CI 0.8-2.3). However, late-pregnancy sole vapers and dual-users had increased risk of SGA compared to non-users (aOR 2.4, 95% CI 1.0-5.7 for sole vapers, and aOR 2.3 95% CI 1.3-4.1 for dual-users). These findings suggest that vapers during pregnancy had similar risk of preterm as non-users but still had elevated risk for restricted fetal growth.

Psychiatric comorbidity in adolescent use and poly-use of combustible, vaporized, and edible cannabis products

Cannabis legalization and commercialization has resulted in novel alternative cannabis products on the market, including edible and vaporized cannabis, which may appeal to youth with psychiatric problems. Psychiatric comorbidity in adolescent use and poly-use (i.e., use of >2 products) of combustible, edible, and vaporized cannabis products has largely gone uninvestigated. This 2015 cross-sectional survey of Los Angeles, California area adolescents (Mage = 16.1, N = 3177) characterized associations of various psychiatric problems with use and poly-use of combustible, edible, and vaporized cannabis. Exposure variables included past 30-day non-cannabis substance use (alcohol, e-cigarettes, combustible cigarettes, and nonmedical prescription opioid and stimulant use; yes/no), and psychiatric problems including past-week depressive symptom frequency, past 6-month ADHD symptom and conduct problem frequency, anhedonia, and five dimensions of impulsivity (sensation seeking, perseverance, lack of premeditation, positive urgency, and negative urgency). Outcome variables included past 30-day use (yes/no) of combustible, edible, and vaporized cannabis, independently, and number of cannabis products used (single, dual-use, poly-use). Results showed that all forms of non-cannabis substance use (ORs range: 13.7-36.1) and all psychiatric symptoms and traits (ORs in SD units range: 1.1-2.1) were positively associated with combustible, edible, and vaporized cannabis product use. The magnitude of comorbidity did not significantly differ by cannabis product type used in most cases. Psychiatric comorbidity was typically stronger in poly-product than single-product cannabis use and greater for externalizing-type than internalizing-type psychiatric problems. Practitioners, policy makers, and scientists should be aware that pervasive psychiatric comorbidity may be observed across the spectrum of cannabis product use among adolescents, particularly poly-product users.

Pine rosin identified as a toxic cannabis extract adulterant

Pine rosin (colophony) has been identified as a potentially new adulterant in cannabis oil. Its inhalation toxicity poses a significant health concern to users. For example, pine rosin fumes are released during soldering, and have been cited as a causative agent of occupational asthma. Symptoms also include desquamation of bronchial epithelium, which has also been observed in e-cigarette or vaping product used-associated lung injury (EVALI) patients. The sample analyzed herein was acquired from a cannabis industry source, also contains medium chain triglycerides and oleamide, the latter of which is a hypnotic that is commonly found in the synthetic marijuana product Spice, or K2. A combination of proton nuclear magnetic resonance (¹H NMR) and high pressure liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESIMS) was used to unambiguously identify major pine rosin ingredients such as abietic and other resin acids. Comparison to commercial samples of pure pine rosin confirmed the assignment.

Vaporization of Marijuana Among Recreational Users: A Qualitative Study

OBJECTIVE

Vaporization of marijuana products, or "vaping," has become a prevalent mode of administration and is typically perceived to hold unique benefits compared to combustible administration methods. Such positive beliefs regarding marijuana vaporization may contribute to its abuse liability. This qualitative study examined cognitions pertaining to vaping among recreational marijuana users.

METHOD

Focus groups were conducted with frequent marijuana users (N = 31; five groups; six to seven per group; M = 5.0 days/week marijuana use). Three topic areas were queried during discussions with the goal of revealing factors that may contribute to the abuse liability of vaporization. These comprised differences between smoking and vaporizing marijuana products, perceived advantages of vaporization, and perceived disadvantages of vaporization. Focus groups lasted approximately 60 minutes and followed a semistructured agenda; the sessions were audio recorded and transcribed for an applied thematic analysis. An executive summary of each group was made and key themes pertaining to vaporization were summarized.

RESULTS

Several themes emerged, including differences between smoking and vaporizing marijuana, convenience, discretion, and efficiency of vaping, perceived health benefits, the absence of traditional smoking rituals, and the high cost of vaporization devices.

CONCLUSIONS

Several factors appear to promote marijuana vaporization, including device aspects (e.g., discreet, convenient), the subjective high, economical efficiency, and perceived harm-reducing and health-promoting effects. These qualitative data highlight unique cognitions about marijuana vaping that may substantially increase its abuse liability. Quantitative research is needed to examine the extent to which cognitions about marijuana vaporization contribute to actual use patterns and problematic behaviors.

The Dangers of Vaping

As our nation turns away from smoking tobacco and toward legalization of marijuana, vaporization of both plants has increased in popularity. There are medical and cultural implications of this new trend which are just recently being reported and investigated. The purpose of this article is to review the scientific and sociological literature as it pertains to the vaporization of both marijuana and tobacco products and the potential medical and cultural implications of this new phenomenon.

Is E-cigarette use a gateway to marijuana use? Longitudinal examinations of initiation, reinitiation, and persistence of e-cigarette and marijuana use

BACKGROUND

Concerns have been raised regarding e-cigarette use as a potential stepping-stone to marijuana use. Based on Kandel's gateway hypothesis, this study investigated if e-cigarette use could lead to marijuana use by testing two hypotheses with a longitudinal national U.S. adult sample, including (1) primary hypothesis: e-cigarette use is a gateway to marijuana use; and (2) falsification hypothesis: marijuana use is not a gateway to e-cigarette use.

METHODS

Adults were extracted from the Population Assessment of Tobacco and Health Study Waves 1-3 (2013-2016). For primary hypotheses, based on baseline e-cigarette use statuses, three study groups were defined, and three logistic regressions were conducted to examine associations between baseline e-cigarette use and follow-up marijuana use initiation, reinitiation, and persistence, respectively. Similarly, for falsification hypotheses, three additional study groups were defined, and three logistic regressions were conducted to examine associations between baseline marijuana use and follow-up e-cigarette use behaviors.

RESULTS

Baseline e-cigarette use was associated with marijuana use initiation and reinitiation (ORs = 2.08, 1.37, respectively, both ps < .05) but not persistence at follow-up. Additionally, baseline marijuana use was associated with only e-cigarette use initiation (OR = 2.23, p < .01) but not reinitiation or persistence at follow-up.

CONCLUSIONS

Findings partially support the gateway hypothesis that e-cigarette use could be a steppingstone to marijuana use reinitiation among the U.S. adults. The mechanisms and behavioral characteristics, such as etiological and psychosocial factors, that may pertain to the progression from e-cigarette use to reinitiation of other substance use should be further investigated to inform effective behavioral, educational, and policy interventions.

Modes of delivery in concurrent nicotine and cannabis use ("co-use") among youth: Findings from the International Tobacco Control (ITC) Survey

BACKGROUND

Cannabis use is more common among nicotine users than non-users. This study characterized concurrent use of nicotine and cannabis ("co-use") among 12,064 youth aged 16-19 years residing in Canada, the United States, and England in 2017. Methods: Data were from the ITC Youth Tobacco & Vaping Survey (Wave 1). Seven modes of cannabis delivery (MOD) were characterized by country of residence and past 30-day use of combusted tobacco and electronic cigarettes. Weighted multivariable regression models were fitted to assess the correlates of co-use and each cannabis MOD. Results: Seventy percent of cannabis users reported nicotine use. Co-users exhibited behavioral and demographic differences compared to exclusive users of either substance. "Smoking cannabis without tobacco" was the most popular form of use (78%). Use of nicotine-containing e-cigarettes was associated with "using an e-cigarette to vape cannabis oil/liquid" (aOR: 4.96, 95%CI: 2.23-11.06). Combustible tobacco use was associated with "smoking cannabis with tobacco in a joint/blunt" (aOR: 2.93, 95%CI: 1.89-4.56). Country-level differences were detected. Conclusions: Nicotine use is substantial among cannabis users, and associations exist between modes of delivery for both drugs. Results underscore the importance of studying cannabis and nicotine use concurrently, and the need to address the use of both substances in developing interventions for youth users.

Urinary Excretion Profile of 11-Nor-9-Carboxy-Δ9-Tetrahydrocannabinol (THCCOOH) Following Smoked and Vaporized Cannabis Administration in Infrequent Cannabis Users

As cannabis has become more accessible, use of alternative methods for cannabis administration such as vaporizers has become more prevalent. Most prior controlled pharmacokinetic evaluations have examined smoked cannabis in frequent (often daily) cannabis users. This study characterized the urinary excretion profile of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCCOOH), the primary analytical outcome for detection of cannabis use, among infrequent cannabis users following controlled administration of both smoked and vaporized cannabis. Healthy adults (N = 17), with a mean of 398 (range 30-1,825) days since last cannabis use, smoked and vaporized cannabis containing 0, 10, and 25 mg of Δ9-tetrahydrocannabinol (THC) across six outpatient sessions. Urinary concentrations of THCCOOH were measured at baseline and for 8 h after cannabis administration. Sensitivity, specificity, and agreement between three immunoassays (IA) for THCCOOH (with cutoffs of 20, 50, and 100 ng/mL) and gas chromatography-mass spectrometry (GC/MS) results (confirmatory concentration of 15 ng/mL) were assessed. THCCOOH concentrations peaked 4-6 h after cannabis administration. Median maximum concentrations (Cmax) for THCCOOH were qualitatively higher after administration of vaporized cannabis compared to equal doses of smoked cannabis. Urine THCCOOH concentrations were substantially lower in this study relative to prior examinations of experienced cannabis users. The highest agreement between IA and GC/MS was observed at the 50 ng/mL IA cutoff while sensitivity and specificity were highest at the 20 and 100 ng/mL IA cutoffs, respectively. Using federal workplace drug-testing criteria (IA cutoff of 50 ng/mL and GC/MS concentration ≥15 ng/mL) urine specimens tested positive in 47% of vaporized sessions and 21% of smoked sessions with active THC doses (N = 68). Urinary concentrations of THCCOOH are dissimilar after administration of smoked and vaporized cannabis, with qualitatively higher concentrations observed after vaporization. Infrequent users of cannabis may excrete relatively low concentrations of THCCOOH following acute inhalation of smoked or vaporized cannabis.

Adolescents' Use of Basic, Intermediate, and Advanced Device Types for Vaping

Introduction

Advanced vaping devices likely pose a greater risk to adolescent health than basic or intermediate devices because advanced devices deliver nicotine more effectively and heat e-liquid to higher temperatures, producing more harmful chemical emissions. However, little is known about adolescents' risk factors for using different device types.

Methods

We used social media to recruit an online sample of 1508 US adolescents aged 15-17 who reported past 30-day use of electronic vaping products (EVPs) in September 2016. We assessed tobacco use, beliefs, and knowledge about EVPs and EVP use behavior, including the device type participants use most frequently. We used multinomial logistic regression to examine differences between adolescents who usually use intermediate versus basic and advanced versus basic devices.

Results

Most respondents usually used modifiable advanced devices (56.8%) rather than basic "cigalike" (14.5%) or pen-style intermediate (28.7%) devices. Use of multiple device types was common, particularly among those who primarily used basic devices. Younger age and less frequent vaping were associated with mainly using basic devices. Adolescents who were older, male, personally bought their main device, and had ever mixed e-liquids were at elevated risk for usually using advanced devices.

Conclusions

Adolescents who primarily use basic devices may be newer users who are experimenting with multiple devices. Future research should examine which adolescents are most likely to transition to advanced devices in order to develop targeted interventions. Regulators should consider strategies to reduce access to all types of EVPs, such as better enforcement of the current ban on sales to minors.

Implications

This research addresses two gaps in research on adolescent electronic vaping product use: (1) characterizing use of advanced devices as distinct from intermediate devices rather than grouping them together and (2) examining factors associated with use of specific device types. This study suggests that there are distinct profiles of adolescents who use primarily basic, intermediate, or advanced devices. Adolescents who most often use basic devices may be new users experimenting with vaping, whereas adolescents who most often use advanced devices appear to be buying devices for themselves and engaging in risky behaviors such as mixing their own e-liquid.

Risk of Persistence and Progression of Use of 5 Cannabis Products After Experimentation Among Adolescents

IMPORTANCE

While a diverse array of cannabis products that may appeal to youth is currently available, it is unknown whether the risk of persistent cannabis use and progression to higher frequency of use after experimentation differs among cannabis products.

OBJECTIVE

To estimate the comparative relative risk of experimental use of 5 cannabis products on use status and frequency of use among adolescents during 12 months of follow-up.

DESIGN, SETTING, AND PARTICIPANTS

In this cohort study, data were collected from 3065 adolescents at 10 high schools in southern California, with baseline data collected in spring 2016, when students were in 11th grade, and 6-month and 12-month follow-up surveys collected in fall 2016 and spring 2017, when students were in 12th grade. Analyses, conducted from April to June 2019, were restricted to 2685 participants who were light or nonusers of any cannabis product (ie, ≤2 days in the past 30 days) at baseline.

EXPOSURES

Number of days of use of each cannabis product (ie, combustible, blunts, vaporized, edible, or concentrated) in the past 30 days at baseline (ie, 1-2 vs 0 days).

MAIN OUTCOMES AND MEASURES

Past 6-month use (ie, yes vs no) and number of days of use in the past 30 days at 6-month and 12-month follow-ups for each product.

RESULTS

Of 2685 individuals in the analytic sample, 1477 (55.0%) were young women, the mean (SD) age was 17.1 (0.4) years, and a plurality (1231 [46.6%]) were Hispanic individuals. Among them, 158 (5.9%) reported combustible cannabis use on 1 to 2 days of the past 30 days at baseline, 90 (3.4%) reported blunt use, 78 (2.9%) reported edible cannabis use, 17 (0.6%) reported vaping cannabis, and 15 (0.6%) reported using cannabis concentrates. In regression models adjusting for demographic characteristics and poly-cannabis product use, statistically stronger associations of baseline use with subsequent past 6-month use at the 6-month and 12-month follow-ups were observed for combustible cannabis use (odds ratio, 6.01; 95% CI, 3.66-9.85) and cannabis concentrate use (odds ratio, 5.87; 95% CI, 1.18-23.80) compared with use of blunts (OR, 2.77; 95% CI, 1.45-5.29) or edible cannabis (OR, 3.32; 95% CI, 1.86-5.95) (P for comparison < .05); vaporized cannabis use (OR, 5.34; 95% CI, 1.51-11.20) was not significantly different from the other products. In similarly adjusted models, we found the association of cannabis use at baseline with mean days of use at the 6-month and 12-month follow-ups was significantly stronger for cannabis concentrate than for other cannabis products; participants who had used cannabis concentrate on 1 to 2 of the past 30 days at baseline (vs 0 days) used cannabis concentrate a mean of 9.42 (95% CI, 2.02-35.50) more days in the past 30 days at the 6-month and 12-month follow-ups (P for comparison < .05).

CONCLUSIONS AND RELEVANCE

Cannabis control efforts should consider targeting specific cannabis products, including combustible cannabis and cannabis concentrate, for maximum public health consequences.

Cannabis legalization, tobacco prevention policies, and Cannabis use in E-cigarettes among youth

BACKGROUND

E-cigarettes are the most popular tobacco product among youth. As more states adopt cannabis legalization policies, youth cannabis use in e-cigarettes is a mounting concern.

METHODS

Data were from the 2016 and 2017 National Youth Tobacco Survey, a nationally-representative repeated cross-sectional survey administered to US middle and high school students. Ever use groups were categorized into e-cigarette ever users, cannabis in e-cigarette ever users, other tobacco ever users, and never users. Weighted multinomial logistic regression compared ever use groups, while controlling for state-level cannabis legalization and tobacco prevention polices, tobacco perceptions and exposures, and sociodemographic variables. Weighted prevalence of ever and current, or past 30 day, tobacco product use was determined by ever use groups.

RESULTS

Compared to e-cigarette ever users, cannabis in e-cigarette ever users increased (Adjusted Relative Risk Ratio (ARRR) = 1.65; p < 0.01) from 2016 to 2017. Medical-only and medical and recreational cannabis laws, and no e-cigarette minimum legal sales age (MLSA) and increased e-cigarette MLSA at 19 or 21 were positively associated with cannabis in e-cigarette ever users (ARRR = 1.34-1.85; p < 0.01, each). Ever and current use of all individual tobacco products was highest among cannabis in e-cigarette ever users compared to e-cigarette and other tobacco ever users.

CONCLUSIONS

Cannabis use in e-cigarettes has increased among youth, and these trends will likely continue as e-cigarettes continue to gain popularity and cannabis legalization policies proliferate. Targeted tobacco and cannabis prevention strategies are needed for youth, especially in states that have implemented cannabis 'medical and recreational laws.

Electronic Cigarettes to Vaporize Cannabis: Prevalence of Use and Associated Factors among Current Electronic Cigarette Users in Germany (DEBRA Study)

Background: In Germany, cannabis is the most widely used illicit drug, and inhalation together with tobacco is most popular. However, it has been described that electronic cigarettes (ECs) are being used to vaporize cannabis (extract). No current data on EC cannabis use in the German population are yet available. Objectives: This study examines the prevalence of EC cannabis consumption for mood changing effects among current EC users, and associated consumer characteristics in Germany. Methods: We used data from the German Study on Tobacco Use (period: 8/2016-01/2019, DEBRA, www.debra-study.info), a nationally representative household survey. EC cannabis use for mood-changing effects was assessed in 504 current EC users (aged ≥ 18 years) of the total sample (N = 32,678). Ever use was defined by: (1) occasional or regular use, or (2) experimental consumption. Associations with socio-demographic consumer characteristics and tobacco smoking were analyzed using multivariable regression analyses. Results: Amongst current EC users, 7.2% had ever vaporized cannabis: 2.3% (95%CI = 1.2-3.9) reported occasional or regular use (1) and 4.8% (95%CI = 3.2-7.1) reported experimental use (2). Age was associated with ever EC cannabis use: highest prevalence rates were found among 18-24-year-olds: 6.5% (95%CI = 2.3-13.1) (1) and 8.0% (95%CI = 3.7-15.8) (2), respectively. The majority (90.2%) of ever EC cannabis users were current tobacco smokers. Conclusions: One in 14 current EC users in Germany has ever vaporized cannabis for mood-changing reasons, and almost all EC cannabis consumers also smoke tobacco. Highest usage rates can be observed among young adults. Hence, trends of EC drug misuse need to be monitored consequently, particularly in young people.

Routes of cannabis administration among females in the year before and during pregnancy: Results from a pilot project

Use of cannabis during pregnancy is on the rise, yet little is known about how women administer cannabis during the perinatal period. This study examined self-reported modes of cannabis administration among women in the year before and during pregnancy, and their association with self-reported cannabis use frequency using data from 585 women screened in 2018-2019 for cannabis use during standard prenatal care in two medical centers in Northern California. The prevalence of cannabis use was 12% before pregnancy and 3% during pregnancy. Among the 71 women who reported cannabis use before pregnancy and the 19 women who reported cannabis use during pregnancy, smoking was the most common mode of administration (58% and 42%), followed by edibles (27% and 16%), vaping (23% and 16%), lotions (11% and 5%), and other (10% and 0%). In the year before pregnancy and during pregnancy, monthly or less use was most common (56% and 58%), followed by weekly use (24% and 26%) and daily use (20% and 16%). Among cannabis users, 43% used more than one mode before pregnancy compared to 15% during pregnancy. Daily cannabis use was most common among women who reported smoking only or smoking in combination with other modes. These novel results indicate that while smoking is the most common mode of cannabis administration during the perinatal period, there is variation in use and co-use of alternative modes. Future studies are needed to understand the relative health effects associated with individual and combined modes of cannabis administration during pregnancy.

Subjective effects of combustible, vaporized, and edible cannabis: Results from a survey of adolescent cannabis users

BACKGROUND

Data from controlled laboratory experiments in adults indicate that the subjective effects of cannabis vary by administration method (e.g., combustible, vaporized). Whether the subjective effects of cannabis experienced in the natural ecology and among adolescents differ by cannabis administration method is unknown. In this observational study, adolescents' retrospective reports of subjective effects after combustible, edible, and vaporized cannabis use were examined.

METHODS

Students from ten public schools in Los Angeles, CA, USA (M[SD] age = 16.1 [.43] years) who reported past 6-month use of combustible, edible, or vaporized cannabis (N = 584) were surveyed on subjective effects experienced after use (yes/no). They were provided with a 12 item self-report checklist of six positive (e.g., relaxed, energetic) and six negative (e.g., drowsy, lazy) subjective effects. For each method of administration, affirmative responses were summed in positive (range: 0-6) and negative (range: 0-6) effect composite scores.

RESULTS

Generalized estimating equations adjusted for demographics and recent cannabis use revealed a graded pattern of differences in positive subjective effects across products, with highest scores for combustible (M[SD] = 3.98[1.76]), followed by edible (M[SD] = 3.58 [2.04]) and vaporized (M[SD] = 3.11 [2.21]) cannabis (all pairwise cross-product contrasts p < .01). Mean negative effect score was highest for edible (M[SD] = 2.27 [1.95]), followed by combustible (M[SD] = 1.94 [1.66]), and vaporized (M[SD] = 1.34 [1.73]) cannabis, respectively (all pairwise contrasts p < .02).

CONCLUSION

Adolescents' reports of subjective effects varied across cannabis administration methods. Combustible cannabis' more desirable subjective effects profile might be indicative of higher abuse liability.

Effects of a Nicotine Fact Sheet on Perceived Risk of Nicotine and E-Cigarettes and Intentions to Seek Information About and Use E-Cigarettes

We examined how a nicotine fact sheet influenced smokers’ beliefs about nicotine and electronic cigarettes (e-cigarettes), a potentially less harmful alternative to conventional cigarettes. In an exploratory online experiment, 756 US adult current and recent former smokers (quit in the past 2 years) were randomized to view a nicotine fact sheet or control messages (bottled water ads). Effects of the nicotine fact sheet on perceived nicotine addictiveness, nicotine risk, comparative risk of e-cigarettes, and dual use intentions were analyzed using log-Poisson regression with robust error. Linear regression analyzed effects on perceived absolute risk and switching and information seeking intentions about e-cigarettes. Compared to control, the nicotine fact sheet doubled the probability of disagreeing that nicotine is the main cause of smoking-related disease (26.2% vs. 12.7%, RR = 2.06, 95% CI = 1.51, 2.82, p < 0.001). However, nearly three quarters of participants viewing the nicotine fact sheet still thought that nicotine is the main cause of smoking-related disease. The nicotine fact sheet increased smokers’ intentions to seek information about e-cigarettes (b = 0.45, 95% CI = 0.15, 0.74, p = 0.003). We did not find evidence suggesting unintended consequences of the nicotine fact sheet on smokers’ e-cigarettes risk perceptions or use intentions (e.g., increased dual use intentions or reduced absolute e-cigarette risk perception).

VpALI-Vaping-related Acute Lung Injury: A New Killer Around the Block

The use of electronic cigarettes, known as vaping, has become increasingly popular over the past decade, particularly in the adolescent and young adult population, often exposing users to harmful chemicals. Vaping has been associated with a heterogeneous group of pulmonary disease. Recently, a multistate epidemic has emerged surrounding vaping-related acute lung injury, prompting the Centers for Disease Control and Prevention to list an official health advisory. In this review, we describe the current literature on the epidemiology, clinical significance, as well as recommended evaluation and treatment of vaping-related lung injury.

Beyond the Bud: Emerging Methods of Cannabis Consumption for Youth

Cannabis continues to be the most widely used illicit substance among youth, as many teens view the risks of cannabis consumption to be low. With cannabis laws becoming lax and dispensaries becoming more prevalent throughout the United States, highly concentrated Δ-9-tetrahydrocannibinol (THC) is becoming readily available. This article examines the available literature on consumption of concentrated THC, focusing on potential consequences of concentrate use among youth. Various methods for consuming concentrated THC, including ingestion of edibles, vaping, and dabbing, are discussed, along with associated risks of each consumption method. Recommendations for health professionals are provided.

E-cigarette use as a potential cardiovascular disease risk behavior

Electronic cigarette (e-cigarette) use is rapidly increasing among youth and adults despite limited information regarding the long-term risks or benefits. The potential impact of e-cigarette use on public health is complex. E-cigarettes are sometimes considered as smoking cessation aids and, to the extent that they are successful in this regard, could have a net population benefit for adult smokers. However, limited knowledge exists about the long-term health effects of e-cigarette use, and research has suggested these novel tobacco products may lead to initiation and continued use among vulnerable populations, including youth. The current review aimed to summarize trends and available scientific information about e-cigarette use, focusing on the potential cardiovascular health risks and benefits, characteristics associated with e-cigarette use, and critical areas for future investigation to inform the research and clinical work of psychologists. Psychologists have a leadership role in mitigating health risks from smoking behavior, and there is a need for rigorous research assessing the impact of e-cigarette use on population health. In addition, psychologists are uniquely qualified to understand the underlying processes regarding decision-making and behaviors around e-cigarette use. Collectively, the research of psychologists in this area can have a substantial impact on patient education, policies, and the development of prevention and intervention programs to promote public health. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Acute Cannabis Toxicity

The change in legal status of cannabis (the botanical species Cannabis sativa, commonly known as marijuana) in the United States has had significant impact on pediatric drug exposures. In states with decriminalization of recreational and medicinal use of cannabis, emergency department visits and poison control center calls for unintentional pediatric cannabis intoxication are on the rise in the last few decades. Exploratory or unintentional ingestions of cannabis-containing products (as opposed to those derived from synthetic cannabinoids, which may mimic the structure and/or function of cannabis, but are not the focus of this article) can lead to significant pediatric toxicity, including encephalopathy, coma, and respiratory depression. With the increasing magnitude of the public health implications of widespread cannabis use, clinicians who care for pediatric patients routinely must be adept in the recognition, evaluation, management, and counseling of unintentional cannabis exposure.

Route of administration effects on nicotine discrimination in female and male mice

BACKGROUND

Use of electronic cigarettes (e-cigarettes) has increased exponentially since their appearance on the U.S. market around 2007. To provide preclinical models of vaping that incorporate olfactory cues and chemosensory effects (including flavors) that play a role in human vaping behavior, the feasibility of using a modified e-cigarette device for delivery of aerosolized nicotine was examined in a nicotine discrimination procedure in mice.

METHODS

Adult female and male C57BL/6 mice were trained to discriminate 0.75 mg/kg subcutaneous (s.c.) nicotine from saline. After determination of a s.c. nicotine dose-effect curve, aerosolized freebase nicotine and nicotine-containing tobacco products (i.e., non-flavored and Arctic Blast e-liquids) were evaluated.

RESULTS

Nicotine (s.c.) dose-dependently substituted in mice of both sexes, although females showed less sensitivity and greater variability. By contrast, aerosolized nicotine, regardless of formulation, produced concentration-dependent increases up to maximum of 46-62% nicotine-associated responding. Brain nicotine concentrations for each sex were similar for s.c. 0.75 mg/kg nicotine and 30 mg/ml freebase nicotine.

CONCLUSIONS

Mice of both sexes readily acquired s.c. nicotine discrimination, but females showed less sensitivity. Further, all three formulations of aerosolized nicotine produced increases in nicotine-like responding in mice of each sex. However, the maximum magnitude of these increases did not engender a similar degree of substitution as s.c. 0.75 mg/kg nicotine, despite similar brain concentrations of nicotine at 30 mg/ml aerosolized nicotine. Additional research is needed for determination of the reason(s); however, results here demonstrate initial feasibility for examination of the discriminative stimulus effects of vaped drugs such as nicotine.

Cannabinoids versus placebo or no intervention for pain: protocol for a systematic review with meta-analysis and trial sequential analysis

INTRODUCTION

Pain is a frequent clinical symptom with significant impact on the patient's well-being. Therefore, adequate pain management is of utmost importance. While cannabinoids have become a more popular alternative to traditional types of pain medication among patients, the quality of evidence supporting the use of cannabinoids has been questioned. The beneficial and harmful effects of cannabinoids in patients with pain is unknown. Accordingly, we aim to assess the efficacy, tolerability and safety of cannabinoids (herbal, plant-derived extracts and synthetic) compared with placebo or no intervention for any type of pain.

METHODS AND ANALYSES

We will conduct a systematic review of randomised clinical trials with meta-analysis and Trial Sequential Analysis to assess the beneficial and harmful effects of cannabinoids in any dose, formulation and duration. We will accept placebo or no treatment as control interventions. We will include participants with any type of pain (acute and chronic pain, cancer-related pain, headache, neuropathic pain or any other types of pain). We will systematically search The Cochrane Library, MEDLINE, Embase, Science Citation Index and BIOSIS for relevant literature. We will follow the recommendations by Cochrane and the Preferred Reporting Items for Systematic Review and Meta-Analysis statement. The risk of systematic errors (bias) and random errors (play of chance) will be assessed. The overall certainty of evidence will be evaluated using the Grading of Recommendations Assessment, Development and Evaluation approach.

ETHICS AND DISSEMINATION

Ethical approval is not a requirement since no primary data will be collected. The findings of this systematic review will be submitted for peer-reviewed publication and disseminated in national and international conferences.

DISCUSSION

Although cannabinoids are now being used to manage different pain conditions, the evidence for the clinical effects are unclear. The present review will systematically assess the current evidence for the benefits and harms of cannabinoids to inform practice and future research.

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.

Modeling drug exposure in rodents using e-cigarettes and other electronic nicotine delivery systems

Smoking tobacco products is the leading cause of preventable death worldwide. Coordinated efforts have successfully reduced tobacco cigarette smoking in the United States; however, electronic cigarettes (e-cigarette) and other electronic nicotine delivery systems (ENDS) recently have replaced traditional cigarettes for many users. While the clinical risks associated with long-term ENDS use remain unclear, advancements in preclinical rodent models will enhance our understanding of their overall health effects. This review examines the peripheral and central effects of ENDS-mediated exposure to nicotine and other drugs of abuse in rodents and evaluates current techniques for implementing ENDS in preclinical research.

Acute Pharmacokinetic Profile of Smoked and Vaporized Cannabis in Human Blood and Oral Fluid

Currently, an unprecedented number of individuals can legally access cannabis. Vaporization is increasingly popular as a method to self-administer cannabis, partly due to perception of reduced harm compared with smoking. Few controlled laboratory studies of cannabis have used vaporization as a delivery method or evaluated the acute effects of cannabis among infrequent cannabis users. This study compared the concentrations of cannabinoids in whole blood and oral fluid after administration of smoked and vaporized cannabis in healthy adults who were infrequent users of cannabis. Seventeen healthy adults, with no past-month cannabis use, self-administered smoked or vaporized cannabis containing Δ9-tetrahydrocannabinol (THC) doses of 0, 10 and 25 mg in six double-blind outpatient sessions. Whole blood and oral fluid specimens were obtained at baseline and for 8 h after cannabis administration. Cannabinoid concentrations were assessed with enzyme-linked immunosorbent assay (ELISA) and liquid chromatography-tandem mass spectrometry (LC-MS-MS) methods. Sensitivity, specificity and agreement between ELISA and LC-MS-MS results were assessed. Subjective, cognitive performance and cardiovascular effects were assessed. The highest concentrations of cannabinoids in both whole blood and oral fluid were typically observed at the first time point (+10 min) after drug administration. In blood, THC, 11-OH-THC, THCCOOH and THCCOOH-glucuronide concentrations were dose-dependent for both methods of administration, but higher following vaporization compared with smoking. THC was detected longer in oral fluid compared to blood and THCCOOH detection in oral fluid was rare and highly erratic. For whole blood, greater detection sensitivity for ELISA testing was observed in vaporized conditions. Conversely, for oral fluid, greater sensitivity was observed in smoked sessions. Blood and/or oral fluid cannabinoid concentrations were weakly to moderately correlated with pharmacodynamic outcomes. Cannabis pharmacokinetics vary by method of inhalation and biological matrix being tested. Vaporization appears to be a more efficient method of delivery compared with smoking.

Aerosol Gas-Phase Components from Cannabis E-Cigarettes and Dabbing: Mechanistic Insight and Quantitative Risk Analysis

Consumption of cannabis by nontraditional methods has surged since the advent of legalization in North America and worldwide. Inhaling cannabis extracts using vaporizers and via dabbing has risen in popularity, while concerns over product safety have not hindered their proliferation. The work herein is the first step toward assessing the safety of vaporizing and dabbing concentrated cannabis extracts as a function of gas-phase reaction products. The gas-phase thermal degradants of Δ⁹-tetrahydrocannabinol (THC) have not been previously investigated. It was found that users may be exposed to concerning degradants such as methacrolein, benzene, and methyl vinyl ketone when using cartridge vaporizers and dabbing. It was shown that THC alone and mixed with terpenes generated similar degradation products and, most notably, elevated levels of isoprene. Importantly, it was shown that added terpenes led to higher levels of gas-phase products compared to THC alone. To estimate cancer and noncancer risks associated with exposure to these and other degradants, quantitative risk assessment was applied to experimentally determined values for dabbing and vaping and literature-sourced levels of hazardous components in cannabis smoke. Overall, gas-phase aerosol products had significantly lower values in dabbing and vaporizing compared to cannabis smoking, although these results should be interpreted in light of potential variations in degradant levels due to disparate usage patterns and the dangers of the higher aerosol concentration of THC.