Correlates and trends in youth co-use of marijuana and tobacco in the United States, 2005-2014

Cannabis Use Disorder Symptoms in Weekly Cannabis Users: A Network Comparison Between Daily Cigarette Users and Nondaily Cigarette Users

Background: Concurrent use (co-use) of cannabis and tobacco is common and associated with worse clinical outcomes compared with cannabis use only. The mechanisms and interactions of cannabis use disorder (CUD) symptoms underlying co-use remain poorly understood. Methods: We examined differences in the symptom presence and symptom network configurations between weekly cannabis users who use tobacco daily (co-users, n=789) or non- or nondaily (nondaily co-users, n=428). Results: First, we identified a range of symptoms (craving, failed reduce or quit attempts, neglected responsibilities, and negative social effects) that are most central to the highly interconnected CUD symptom network. Risky cannabis use was mostly associated with negative social and health effects, and independent of other CUD symptoms. Craving symptoms act as a bridge between different CUD and withdrawal symptoms. Among co-users, (1) craving is more strongly associated with negative psychosocial effects, (2) feelings of depression and negative health effects are more central to the network, and (3) the negative health effects are more strongly associated with failed attempts to reduce or quit attempts compared with nondaily co-users. Discussion: Our results go beyond existing findings focused on the mere increase in CUD symptom presence, and speak to the potential synergistic effects of co-use on dependence and withdrawal symptoms. We outline clinical implications with respect to targeting specific CUD symptoms in co-users, and point to future research to disentangle tobacco and cannabis craving symptoms.

Tobacco and alcohol co-use: Lifestyle and sociodemographic factors, and personality aspects as potential predictors in the "Seguimiento Universidad de Navarra" cohort

Tobacco and alcohol co-use are two major lifestyle modifiable risk factors. Understanding the determinants of both behaviors helps to develop interventions to prevent these exposures. However, previous studies have focused on predictors of individual tobacco or alcohol use. This study aims to explore the potential predictors of tobacco and alcohol co-use among Spanish university graduates from the "Seguimiento Universidad de Navarra" (SUN) cohort study. A total of 7175 participants who were co-users of tobacco and alcohol were selected for this cross-sectional analysis. Their mean age was 39.1 years (12.04 SD) and 57.3% were women. Univariate regression models were used to select the potential predictors of tobacco and alcohol co-use, and the areas under the ROC curves (AUC) were calculated. Multivariable logistic regression models were used to create a predictive model. Baseline potential predictors included sociodemographic factors, lifestyle habits, and perceived personality aspects. In the multivariable model, the main significant potential predictors of tobacco and alcohol co-use were driving under the influence of alcohol (odds ratio [OR] = 1.65 [1.43-1.90]), drinking 1-2 cups of coffee daily (OR = 1.50 [1.24-1.84]), drinking three or more cups of coffee daily (OR = 1.61 [1.35-1.91]), and doing more physical activity than recommended (OR = 1.18 [1.02-1.34]) when compared with the reference group. Conversely, those who were married (OR = 0.87 [0.75-0.99], ate at home 7 days a week (OR = 0.69 [0.60-0.80]), or had a high perceived level of competitiveness (OR = 0.83 [0.72-0.95]) had a lower risk of co-use (AUC 0.61 [confidence interval 95% 0.59-0.63]), compared to the reference group. These results could be used by healthcare professionals, especially nurses, to effectively assess patients at higher risk of tobacco and alcohol co-use. [Correction added on 16 February 2024, after first online publication: The abstract section has been revised to provide more clarity in this version.].

Patterns of blunt and cigar use in the United States, 2015-2019

Background

The use of cigars for blunts (i.e., cannabis rolled in cigar paper) is well-documented; proportions of cigar and blunt use and associated characteristics are less studied.

Methods

Pooled data from the 2015-2019 National Survey on Drug Use and Health (NSDUH) were analyzed in 2023. Respondents aged 12+ who reported past 30-day cigar use were categorized into three mutually exclusive use categories: (1) exclusively cigars, (2) exclusively blunts, and (3) both cigars and blunts. We examined associations between cigar-blunt use category and sociodemographic characteristics.

Results

Among people 12 and older who reported past 30-day cigar use, 48.6% (95% CI=47.6-49.6) reported exclusive cigar use; 44.3% (95% CI=43.3-45.3) reported exclusive blunt use; and 7.2% (95% CI=6.8-7.6) reported cigars and blunts. The prevalence differed by age, with exclusively blunts most prevalent among youth (72.5% [95% CI=70.7-74.3]) and young adults (62.4% [95% CI=61.4-63.5]), and exclusively cigars most prevalent among adults 26+ (61.2% [95% CI=59.8-62.5]). Exclusive blunt users smoked more days in the past month (17.5; 95% CI=16.8-18.2), compared to 13.8 days (95% CI=13.2-14.4) for cigar and blunt users, and 7.7 days (95% CI=7.5-8.0) for exclusive cigar users. There were significant differences in characteristics, with exclusive blunt use more prevalent among female (41.6%; 95% CI=40.3-42.9) and Hispanic (18.2%; 95% CI=17.3-19.2) participants.

Conclusions

Exclusive blunt use was the most prevalent pattern of past-30-day cigar use among youth and young adults. Those who use cigars as blunts smoke more cigars per month, suggesting this may be an important group for additional education and policy efforts.

In-Home Cannabis Smoking Among a Cannabis-Using Convenience Sample from the Global Drug Survey: With Weighted Estimates for U.S. Respondents

Introduction: Secondhand and thirdhand tobacco smoke exposure most often occur at home, but little is known about occurrences of in-home cannabis smoking. We ascertained in-home cannabis smoking reported by all cannabis-using (i.e., used in the last 12 months) respondents to the Global Drug Survey (GDS; international-GDS sample), and among U.S. cannabis-using respondents (US-GDS sample). Materials and Methods: We used data collected November 2019-January 2020 for the 2020 GDS, an annual anonymous, cross-sectional survey; respondents were 16+ years old, from 191 countries. We estimated any and daily in-home cannabis smoking in the last 30 days among international-GDS respondents (n=63,797), using mixed effects logistic regression. US-GDS respondents (n=6,580) were weighted to the covariate distribution of the nationally representative 2018 National Survey on Drug Use and Health cannabis-using sample, using inverse odds probability weighting, to make estimates more generalizable to the U.S. cannabis-using population. Results: For the international-GDS cannabis-using respondents, any in-home cannabis smoking was reported by 63.9% of men, 61.9% of women, and 68.6% of nonbinary people; and by age (<25 years old=62.7%, 25-34 years old=65.0%, and 35+ years old=62.8%). Daily in-home cannabis smoking was highest among nonbinary (28.7%) and respondents 35+ years of age (28.0%). For the weighted US-GDS cannabis-using respondents, any in-home cannabis smoking was reported by 49.8% of males and 61.2% of females; and by age (<25 years old=62.6%, 25-34 years old=41.8%, 35+ years old=57.9%). Weighted daily in-home smoking was 23.2% among males and 37.1% among females; by age (<25 years old=34.8%, 25-34 years old=27.8%, and 35+ years old=21.6%). Conclusions: There was high daily cannabis smoking in homes of international-GDS and US-GDS respondents who used cannabis in the last 12 months. In part, due to cannabis legalization, the number of users worldwide has increased over the past decade. Criminal stigma historically associated with cannabis continues to drive those users indoors. In this context, our findings support further investigation of cannabis use behavior to understand how often people are exposed to secondhand and thirdhand cannabis smoke and the consequences of that exposure.

Associations of daily alcohol, cannabis, combustible tobacco, and e-cigarette use with same-day co-use and poly-use of the other substances

BACKGROUND

Young adults frequently use alcohol, cannabis, and tobacco together. Given the increased prevalence of e-cigarette use and recreational cannabis use, we investigated daily patterns of alcohol, cannabis, and tobacco use and distinguished combustible tobacco from e-cigarettes.

METHODS

Young adult college students (N=341) reporting past-month alcohol and cannabis use "at the same time so that their effects overlapped" completed two 28-day bursts of repeated daily surveys. Exposures were day- and person-level use of each substance. Outcomes were (1) same-day co-use of each remaining substance or (2) poly-use of the other substances.

RESULTS

Daily use of alcohol, cannabis, combustible cigarettes, and e-cigarettes increased the odds of same-day co-use of the other substances (except combustible tobacco with e-cigarettes) and each poly-use outcome. The influence of person-level substance use on daily substance use was less consistent. Only e-cigarette use increased the odds of daily alcohol use. Use of either tobacco product but not alcohol increased the odds of daily cannabis use. Person-level alcohol and cannabis use increased the odds of daily use of either tobacco product but use of one tobacco product was not associated with daily use of the other product.

CONCLUSIONS

These findings increase our understanding of emerging daily patterns of alcohol, cannabis, and tobacco co-use, and the impact of different tobacco products. Future work is needed to extend this research into non-college samples and people who use tobacco but do not use alcohol and cannabis simultaneously, and examine daily chronologies of multiple substances that could serve as dynamic markers of risk.

Associations between tobacco and cannabis use and anxiety and depression among adults in the United States: Findings from the COVID-19 citizen science study

BACKGROUND

Little is known about whether people who use both tobacco and cannabis (co-use) are more or less likely to have mental health disorders than single substance users or non-users. We aimed to examine associations between use of tobacco and/or cannabis with anxiety and depression.

METHODS

We analyzed data from the COVID-19 Citizen Science Study, a digital cohort study, collected via online surveys during 2020-2022 from a convenience sample of 53,843 US adults (≥ 18 years old) nationwide. Past 30-day use of tobacco and cannabis was self-reported at baseline and categorized into four exclusive patterns: tobacco-only use, cannabis-only use, co-use of both substances, and non-use. Anxiety and depression were repeatedly measured in monthly surveys. To account for multiple assessments of mental health outcomes within a participant, we used Generalized Estimating Equations to examine associations between the patterns of tobacco and cannabis use with each outcome.

RESULTS

In the total sample (mean age 51.0 years old, 67.9% female), 4.9% reported tobacco-only use, 6.9% cannabis-only use, 1.6% co-use, and 86.6% non-use. Proportions of reporting anxiety and depression were highest for the co-use group (26.5% and 28.3%, respectively) and lowest for the non-use group (10.6% and 11.2%, respectively). Compared to non-use, the adjusted odds of mental health disorders were highest for co-use (Anxiety: OR = 1.89, 95%CI = 1.64-2.18; Depression: OR = 1.77, 95%CI = 1.46-2.16), followed by cannabis-only use, and tobacco-only use. Compared to tobacco-only use, co-use (OR = 1.35, 95%CI = 1.08-1.69) and cannabis-only use (OR = 1.17, 95%CI = 1.00-1.37) were associated with higher adjusted odds for anxiety, but not for depression. Daily use (vs. non-daily use) of cigarettes, e-cigarettes, and cannabis were associated with higher adjusted odds for anxiety and depression.

CONCLUSIONS

Use of tobacco and/or cannabis, particularly co-use of both substances, were associated with poor mental health. Integrating mental health support with tobacco and cannabis cessation may address this co-morbidity.

Associations of polygenic risk scores for smoking heaviness and lifetime cannabis use with tobacco and cannabis co-use trajectories among African Americans

BACKGROUND

We aimed to identify distinct trajectories of tobacco, cannabis, and their co-use among African Americans, and to investigate whether these patterns were associated with polygenic risk scores (PRS) for tobacco and cannabis use.

METHOD

Participants (N=428 participants; 50.9% male) were initially recruited for an elementary school-based prevention in a Mid-Atlantic city when they were in first grade. From ages 14-26, participants reported on their frequency of tobacco and cannabis use in the past year during annual assessments. DNA was collected from participants at age 21. PRS for smoking heaviness (i.e., cigarettes per day) and lifetime cannabis use were created based on genome-wide association study results derived from Liu et al. (2019) and Pasman et al. (2018), respectively.

RESULTS

We identified five distinct trajectories of tobacco and cannabis co-use, including (1) Low Tobacco and Cannabis Use, (2) Adolescent Limited Tobacco and Cannabis Use, (3) Experimental Cannabis, Young Adult Increasing Tobacco, (4) Experimental Tobacco, Young Adult Increasing Cannabis, and (5) High, Chronic Tobacco and Cannabis Use. Compared to the Low Tobacco and Cannabis Use subgroup, individuals in the High, Chronic Tobacco and Cannabis Use subgroup had greater PRS for smoking heaviness, and individuals in the Experimental Cannabis, Young Adult Increasing Tobacco subgroup had higher PRS for lifetime cannabis use.

CONCLUSIONS

Polygenic risk for lifetime cannabis use and smoking heaviness is associated with the developmental progression of tobacco and cannabis co-use among African Americans, furthering knowledge on the etiology of co-use in this population.

Objective and perceived measures of tobacco marketing are uniquely associated with cigar use

BACKGROUND

Few studies have examined associations between perceived and objective exposure to tobacco marketing and cigar use, which is the second most commonly used tobacco product by youth.

METHODS

We used Geographic Ecological Momentary Assessment data over 14 days from youth aged 16-20 years (n=83 participants, n=948 observations; 34% past month users of any tobacco product) in eight city areas in California. Tobacco outlets in study cities were visited by trained observers to record outlet Global Positioning System (GPS) point locations and outdoor tobacco marketing. We assessed daily perceived exposure to tobacco marketing within participants' activity spaces; daily objective exposure to tobacco outlets with outdoor marketing within 50 m of activity space polylines (number of outlets and time spent near outlets) and daily cigar use excluding and including blunts.

RESULTS

Controlling for demographics and baseline tobacco use, results from mixed logistic regression models showed that greater perceived exposure to tobacco marketing was positively associated with higher odds of cigar use each day, excluding blunts (adjusted odds ratios (aOR): 2.00; 95% CI 1.03 to 3.87) and including blunts (aOR: 1.87; 95% CI 1.26 to 2.77). Also, exposure to a greater number of tobacco outlets with outdoor marketing was associated with higher odds of cigar use each day, excluding blunts (aOR: 1.34; 95% CI 1.01 to 1.78), but not including blunts.

CONCLUSIONS

Tobacco control efforts should consider both perceived and objective exposure to tobacco marketing and unique associations with blunt use to prevent cigar use.

Latent Classes of Tobacco and Cannabis Use among Youth and Young Adults in the United States

Background: Research characterizing patterns of tobacco and cannabis use by product type and route of administration among youth and young adults (YAs) is limited. Methods: We conducted latent class analysis of tobacco and cannabis use (i.e., cigarettes, electronic nicotine delivery systems (ENDS), cigars, blunts, cannabis vaping, and other cannabis use (without blunting/vaping)) among youth (ages 15-17) and YAs (ages 18-24) who used at least one product in the past 30 days, using data from the Population Assessment of Tobacco and Health Study (Wave 4, 2016-2017). We used multinomial logistic regression models to examine associations between sociodemographic characteristics and use classes. Results: The latent use classes for youth included cigarettes (2.5%), ENDS (2.6%), blunts (2.5%), other cannabis (6.3%), ENDS + cannabis vaping (2.7%), and cigarettes + cigars + other cannabis (1.5%), while the latent use classes for YAs included cigarettes (11.7%), ENDS (3.9%), blunts (5.3%), other cannabis (7.0%), cigarettes + cigars (8.2%), and cigarettes + ENDS + cannabis vaping (4.9%). We compared use classes to never/former use for youth (82.0%) and YAs (59.0%) and found that they differed by each sociodemographic characteristic. For example, non-Hispanic Black YAs had higher odds of cigarettes + cigar use compared to non-Hispanic White YAs, whereas racial/ethnic minority youth and YAs had lower odds of other dual/poly use groups compared to their non-Hispanic White counterparts. Conclusions: We observed differences in use classes by sociodemographic characteristics for youth and YAs. Health professionals must consider tobacco and cannabis use patterns when implementing prevention and cessation interventions.

A latent class analysis of patterns of tobacco and cannabis use in Australia and their health-related correlates

INTRODUCTION

The shifting landscape in Australia's tobacco and cannabis policies and emerging new products and modes of administration may increase experimentation and the risks of addiction to these drugs.

METHODS

We analysed cross-sectional data from the 2019 National Drug Strategy and Household Survey (n = 22,015) of Australians aged 14 and above. Latent class analysis was used to identify distinct groups based on types of tobacco and cannabis products used. The socio-demographic, health-rated correlates and past-year substance use of each latent class was examined.

RESULTS

A four-class solution was identified: co-use of tobacco and cannabis (2.4%), cannabis-only (5.5%), tobacco-only (8.0%) and non-user (84.0%). Males (odds ratio [OR] range 1.5-2.9), younger age (OR range 2.4-8.4), moderate to high psychological distress (OR range 1.3-3.0), using illicit substances in the last year (OR range 1.41-22.87) and high risk of alcohol use disorder (OR range 2.0-21.7) were more likely to be in the tobacco/cannabis use classes than non-users. Within the co-use class, 78.4% mixed tobacco with cannabis and 89.4% had used alcohol with cannabis at least once.

DISCUSSION AND CONCLUSIONS

Approximately 16% of respondents used tobacco or cannabis, or both substances, and no major distinct subgroups were identified by the use of different product types. Mental health issues and the poly-substance use were more common in the class who were co-users of cannabis and tobacco. Existing policies need to minimise cannabis and tobacco-related harms to reduce the societal burden associated with both substances.

Educational Attainment and Differences in Patterns of Alcohol, Cannabis, and Tobacco Use Among Young Adults

Multigroup latent profile analysis examined whether patterns of alcohol, cannabis, and tobacco use varied between college student and nonstudent young adults ( N = 745), and profiles were characterized by alcohol- and drug-related problems, psychological distress, and perceived stress. Findings supported three profiles (high use across substances, primarily high tobacco use, and low use across substances) among students. Students in the high use group, relative to other groups, experienced the highest number of problems and psychological distress. Among nonstudents, two profiles emerged (high use across substances and primarily high tobacco use), and noncollege participants in the high use group experienced the highest problems, psychological distress, and perceived stress. Students, compared to nonstudents, reported more variability in their substance use profiles, as a low substance use group was not observed among nonstudents. Prevention and intervention efforts should target nonstudents, which could aid in reducing negative health outcomes based on disparities in education.

The Role of Cigarillo Flavor in the Co-Use of Cigarillos and Cannabis among Young Adults

Background: Research suggests flavor facilitates cigarillo use, but it is unknown if flavor impacts patterns of co-use of cigarillos and cannabis ("co-use"), which is common among young adult smokers. This study's aim was to determine the role of the cigarillo flavor in co-use among young adults. Methods: Data were collected (2020-2021) in a cross-sectional online survey administered to young adults who smoked ≥2 cigarillos/week (N = 361), recruited from 15 urban areas in the United States. A structural equation model was used to assess the relationship between flavored cigarillo use and past 30-day cannabis use (flavored cigarillo perceived appeal and harm as parallel mediators), including several social-contextual covariates (e.g., flavor and cannabis policies). Results: Most participants reported usually using flavored cigarillos (81.8%) and cannabis use in the past 30 days ("co-use") (64.1%). Flavored cigarillo use was not directly associated with co-use (p = 0.90). Perceived cigarillo harm (β = 0.18, 95% CI = 0.06, 0.29), number of tobacco users in the household (β = 0.22, 95% CI = 0.10, 0.33), and past 30-day use of other tobacco products (β = 0.23, 95% CI = 0.15, 0.32) were significantly positively associated with co-use. Living in an area with a ban on flavored cigarillos was significantly negatively associated with co-use (β = -0.12, 95% CI = -0.21, -0.02). Conclusions: Use of flavored cigarillos was not associated with co-use; however, exposure to a flavored cigarillo ban was negatively associated with co-use. Cigar product flavor bans may reduce co-use among young adults or have a neutral impact. Further research is needed to explore the interaction between tobacco and cannabis policy and use of these products.

Determining the impact of cannabis use and severity on tobacco cessation outcomes: study protocol for a prospective tobacco treatment trial

BACKGROUND

Several evidence-based tobacco cessation treatment strategies exist, though significant barriers to cessation remain which must be addressed to improve abstinence rates for sub-populations of those smoking cigarettes. Cannabis co-use among those who use tobacco is common and appears to be increasing among adults in the United States (US). The literature evaluating the impact of cannabis use on tobacco cessation has been mixed and has several important limitations, which precludes development of treatment recommendations specific to individuals who use tobacco and co-use cannabis. To date, no prospective studies have evaluated the impact of cannabis use and severity on tobacco cessation or quantified cannabis use changes during tobacco treatment to assess for concurrent reductions, abstinence, or compensatory (i.e., increased) cannabis use. This study's aims are to: (1) evaluate tobacco cessation outcomes among participants who co-use cannabis compared to participants only using tobacco, (2) using daily diaries and biochemical verification, assess changes in cannabis use during tobacco treatment, and (3) assess for a dose-dependent impact of cannabis use on tobacco cessation.

METHOD

A multi-site, prospective, quasi-experimental 12-week tobacco treatment trial enrolling treatment-seeking adults (ages 18-40; N = 208) from three sites across South Carolina (US) who use tobacco daily and oversampling (2:1) those who co-use cannabis. Participants receive tobacco cessation pharmacotherapy (varenicline) paired with behavioral support, while cannabis use is not addressed as part of treatment. The primary outcome is 7-day point prevalence tobacco abstinence at the week 12 end of treatment visit, measured via biochemical verification and self-report. Secondary outcome measures include changes in cannabis use (via biochemical verification and self-report) during tobacco cessation treatment.

DISCUSSION

Results from this trial have the potential to inform tobacco treatment among those co-using cannabis, which may require a tailored approach to address the role of cannabis in quitting tobacco.

TRIAL REGISTRATION

The trial is registered with ClinicalTrials.gov: NCT04228965. January 14th, 2020.

Cigarette, electronic cigarette, and marijuana use among young adults under policy changes in California

Introduction

Since 2016, California has implemented a series of policies, including prohibiting the sale of tobacco products and electronic cigarettes (e-cigarettes) to persons under 21, cigarette tax increase, and recreational marijuana legalization. The study aims to examine the use of cigarettes, e-cigarettes, and marijuana among young adults (ages 18-25) and their associations with other factors in the context of these policy changes.

Methods

We used the data from the California Health Interview Survey (CHIS) 2017-2018 to compare the rates of using cigarettes, e-cigarettes, and marijuana separately or any use of the three. Using CHIS 2018 data, weighted logistic regression models were used to examine associations of using cigarettes, e-cigarettes, and marijuana separately or any use of these products/substance with demo-socioeconomic factors, psychological distress, and use of each product/substances.

Results

Cigarette smoking remained flat while the use of e-cigarettes and marijuana escalated among young adults from 2017 to 2018. Using tobacco products increased the use of marijuana or vice versa among young adults. Severe psychological distress was significantly associated with cigarette use (adjusted odds ratio [AOR] = 4.06; 95% CI = 1.32, 12.55), marijuana use (AOR = 2.32; 95% CI = 1.10, 4.48), and any use (AOR = 4.11; 95% CI = 1.93, 8.77). Moderate psychological distress was also significantly associated with the use of these products/substance. Underage (ages 18-20) young adults had lower odds of using cigarettes than other young adults (ages 21-25).

Conclusions

Our findings highlight the importance of addressing the use of cigarettes, e-cigarettes, and marijuana simultaneously through policies to curtail tobacco and marijuana use among young adults.

PATH to understanding cannabis and nicotine initiation and co-use among emerging adults

OBJECTIVES

The purpose of this study was to describe the characteristics and age of initiation of nicotine and cannabis use, with a particular focus on the emerging adult period (ages 18-24 years) and concurrent use of nicotine with cannabis.

DESIGN

A secondary analysis of Population Assessment of Tobacco and Health (PATH).

SAMPLE

32,078 participants from a nationally representative study of tobacco use and health outcomes.

MEASUREMENT

Variables of interest included ever use, regular use and age of initiation (first-time use) of nicotine (including tobacco) and/or cannabis and selected demographic factors.

RESULTS

Ever-use of nicotine was associated with a 13-fold increase in the likelihood of having ever used cannabis. Among those who reported cannabis use, 96.4% had also used nicotine. While initiation in adolescence was most common, 27.1% of those who use nicotine and 34.9% of those who use cannabis initiated during emerging adulthood. Among regular users of nicotine, 41.5% began regular use in emerging adulthood.

CONCLUSIONS

These findings underscore the continued susceptibility of emerging adults to initiation of these substances. Co-use of nicotine and cannabis is an understudied phenomenon in emerging adults with significant potential to cause harm and should be a public health priority.

Simultaneous quantification of urinary tobacco and marijuana metabolites using solid-supported liquid-liquid extraction coupled with liquid chromatography tandem mass spectrometry

Co-exposure to tobacco and marijuana has become common in areas where recreational marijuana use is legal. To assist in the determination of the combined health risks of this co-exposure, an analytical method capable of simultaneously measuring tobacco and marijuana metabolites is needed to reduce laboratory costs and the required sample volume. So far, no such analytical method exists. Thus, we developed and validated a method to simultaneously quantify urinary levels of trans-3'-hydroxycotinine (3OH-COT), cotinine (COT), and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (COOH-THC) to assess co-exposure to tobacco and marijuana. Urine (200 µL) was spiked with labelled internal standards and enzymatically hydrolyzed to liberate the conjugated analytes before extraction using solid-supported liquid-liquid extraction (SLE) with ethyl acetate serving as an eluent. The target analytes were separated on a C18 (4.6 × 100 mm, 5 μm) analytical column with a gradient mobile phase elution and analyzed using tandem mass spectrometry with multiple reaction monitoring of target ion transitions. Positive electrospray ionization (ESI) was used for 3OH-COT and COT, while negative ESI was used for COOH-THC. The total run time was 13 min. The extraction recoveries were 18.4-23.9 % (3OH-COT), 65.1-96.8 % (COT), and 80.6-95.4 % (COOH-THC). The method limits of quantification were 5.0 ng/mL (3OH-COT) and 2.5 ng/mL (COT and COOH-THC). The method showed good accuracy (82.5-98.5 %) and precision (1.22-6.21 % within-day precision and 1.42-6.26 % between-day precision). The target analytes were stable for at least 144 h inside the autosampler (10 °C). The analyses of reference materials and 146 urine samples demonstrated good method performance. The use of a 96-well plate for preparation makes the method useful for the analysis of large numbers of samples.

[Individual and contextual factors associated with smoking among young Brazilian adults]

Young people receive special attention regarding smoking as it is a period of life in which the use of this and other substances generally starts and is consolidated. There are no studies on risk factors associated with young adults with a representative sample from Brazil that take into consideration individual and contextual aspects. The objective was to identify factors associated with smoking among young Brazilian adults aged 18 to 24 years, considering the combined influence of individual and contextual factors assessed through the Municipal Human Development Index (MHDI). It involved a cross-sectional, population-based study that used data from the 2019 National Health Survey. Using the Poisson multilevel model with robust variance for estimating the Prevalence Ratio, individual variables were analyzed, and the MHDI as a contextual variable in each Federative Unit. In addition to individual factors, the MHDI was also associated with smoking among young people, with an increase in the prevalence of tobacco consumption among young people as the state's MHDI increases (p<0.001), indicating that living in a state with better conditions according to the MHDI, socioeconomic status is associated with a higher probability of young people smoking when compared to those residing in other states.

Cigarillo Flavor and Motivation to Quit among Co-Users of Cigarillos and Cannabis: A Structural Equation Modeling Approach

Flavored cigar restrictions have the potential to benefit public health. Flavor availability facilitates cigarillo use, but it is unknown if flavor impacts patterns of co-use of cigarillos and cannabis, an increasingly prevalent behavior among young adults. Data were collected (2020-2021) in a cross-sectional online survey administered to a convenience sample of young adults who smoked cigarillos from 15 areas with high cigar use prevalence. We assessed the relationship between flavored cigarillo use and motivation to quit cannabis and cigarillo use among past 30-day co-users (N = 218), as well as several covariates (e.g., cigarillo price and flavor/cannabis policy). Flavored cigarillo perceived appeal and harm were hypothesized parallel mediators. Most co-users reported usually using flavored cigarillos (79.5%), which was not significantly associated with motivation to quit cigarillos or cannabis. Perceived cigarillo harm (β = 0.17, 95% CI = 0.00, 0.33), advertising exposure (β = 0.12, 95% CI = 0.00, 0.24), and income (among racial/ethnic minorities; β = -0.13, 95% CI = -0.25, -0.02) were significant predictors of motivation to quit cigarillos. There were no significant predictors of motivation to quit cannabis. Cigarillo flavor was not associated with motivation to quit, so findings could suggest that banning flavors in cigars may have a neutral impact on co-use with cannabis among young adults.

Additive roles of tobacco and cannabis co-use in relation to delay discounting in a sample of heavy drinkers

RATIONALE

Alcohol use disorder (AUD) is associated with steeper delay discounting rates; however, it is unknown whether substance co-use, particularly cannabis use, has an additive effect on discounting rates among heavy drinkers. Furthermore, it is unclear whether substance co-use and delay discounting are independently associated with AUD severity.

OBJECTIVES

The purpose of this study was to determine whether alcohol, tobacco, and cannabis co-use impacts delay discounting rates. We also sought to determine whether substance co-use and delay discounting were associated with AUD symptom counts.

METHODS

The study sample was culled from several human laboratory studies and consisted of 483 heavy drinking individuals who completed a baseline visit (prior to experimental procedures). Participants were divided into groups based on self-reported alcohol, tobacco, and cannabis use during the past 30 days: alcohol only (n = 184), alcohol + cigarettes (n = 89), alcohol + cannabis (n = 82), and tri-use (n = 128). We examined discounting rates across the 4 groups and used multiple linear regression to test whether co-use and delay discounting were associated with AUD symptoms.

RESULTS

After adjusting for covariates, individuals in the alcohol + cannabis group and the tri-use group had steeper discounting rates relative to the alcohol-only group. In addition, tri-use and delay discounting rates were independently correlated with a greater number of AUD symptoms.

CONCLUSIONS

Delay discounting rates were significantly greater among subgroups reporting cannabis use providing partial support for an additive effect, while also highlighting the importance of co-use substance type. Both tri-use and delay discounting were associated with greater AUD severity, which may provide relevant intervention targets.

Youth risk profiles and their prediction of distal cannabis and tobacco co-use in the Population Assessment of Tobacco Health (PATH)

Background: Co-use of cannabis and tobacco is common and increases negative behavioral, physical and mental health consequences. This study aimed to describe latent profiles of youth internalizing and externalizing problems, sensation seeking, and family environment in the US and their relationships with substance co-use. Methods: Data come from the Population Assessment of Tobacco Health (PATH). Using latent profile analysis with a distal outcome, we conducted a secondary data analysis examining relationships between latent profiles and the distal outcome of cannabis/tobacco use and co-use one year later. Participants were a nationally representative sample of youth ages 12-17 (N = 13,651). Results: We identified five youth subgroups: (1;11%) Family Risk, (2;32%) Family Protection with Very Low Internalizing, (3;21%) Family Protection with High Youth Risk, (4;24%) Family Protection with Moderate Youth Risk, (5;12%) Family Risk with High Youth Risk. Relationships between group membership and tobacco/cannabis outcomes, one year later, indicated that the least likely tobacco/cannabis users were the Family Protection with Very Low Internalizing class (no lifetime use probability (PR)=0.86, standard error (SE)=0.007; no 30-day use PR = 0.96, SE = 0.004). In contrast, the Family Risk with High Youth Risk class had the highest probability of both co-use (lifetime co-use PR = 0.33; SE = 0.014; 30-day co-use PR = 0.10; SE = 0.010) and single substance use (probability of lifetime single substance use PR = 0.30; SE = 0.013; 30-day single substance use PR = 0.24; SE = 0.014). Conclusions: A "protective but reactive" risk buffering pattern effect of family factors on youth factors was observed in that the lowest rates of co-use were observed in the three classes with family protection. These findings highlight the need for interventions addressing multiple domains and focusing on youth and family risk factors.

Cannabis Abuse and Perioperative Complications After Treatment of Intracranial Aneurysms: A Nationwide Analysis

OBJECTIVE

In the present retrospective cohort analysis, we examined the differences in baseline characteristics and peri- and postoperative outcomes stratified by 3 groups: cannabis abuse or dependence versus none, surgical versus endovascular treatment, and unruptured and ruptured intracranial aneurysms.

METHODS

A study population of 26,868 patients was defined using the 2009-2016 National Inpatient Sample database. The baseline characteristics were compared between the cannabis and no-cannabis groups, and the traits that differed significantly were factored into the multivariate analysis using 1:1 propensity score matching. The matched groups were analyzed to compare the cannabis and no-cannabis cohorts for the following endpoints: mortality, length of stay, discharge disposition, total hospital charges, and several peri- and postoperative outcomes.

RESULTS

In the surgically and endovascularly treated groups for unruptured intracranial aneurysms, those in the cannabis group were more likely to be male and younger and to smoke tobacco than were those in the no-cannabis group. After matching, no significant endpoint differences were noted. Similarly, in the surgically and endovascularly treated ruptured aneurysm groups, those in the cannabis group were more likely to be male and younger and to smoke tobacco. After matching, the cannabis group within the endovascular treatment group had had a longer length of stay and were more likely to have developed any hydrocephalus, obstructive hydrocephalus, sepsis, and acute kidney injury. Those in the cannabis group who had undergone surgery were more likely to have developed any hydrocephalus, specifically, communicating hydrocephalus.

CONCLUSIONS

The cannabis group with ruptured intracranial aneurysms was more likely to experience certain adverse outcomes after surgical or endovascular treatment compared with the no-cannabis group. However, such was not the case for cannabis abusers treated for unruptured aneurysms.

Changes in cannabis, tobacco, and alcohol use among sexually active female adolescents and young adults over a twelve-year period ending in 2019

BACKGROUND

The United States has experienced an increasing divergence in cannabis, tobacco, and alcohol use among adolescents and young adults (AYA). We assessed the changes in cannabis, tobacco and alcohol use in an inner-city population of predominantly minority AYA females attending a large adolescent-specific health center in New York City.

METHODS

This was a longitudinal study of AYA women recruited and followed over a twelve-year period between 2007 and 2019. Lifetime and past 30-day use were assessed by self-administered questionnaire every six months. In addition, we assessed associations with race, ethnicity, sexual behaviors, receipt of social services, living situation at home (e.g., with or without parents), and use of other drugs.

RESULTS

Participants included 1549 AYA females aged 13-21 at baseline, 95% of whom were youth of color. Use of cannabis increased significantly over the twelve-year period, with frequent cannabis use (≥20 times in 30-days) increasing almost 18% per year (OR = 1.18; 95%CI:1.13-1.23). In contrast, past 30-day tobacco use declined over the same period (OR = 0.86; 95%CI:0.83-0.89). Past 30-day cannabis use was more likely among African Americans (OR = 1.33; 95%CI:1.08-1.63), women who had sex with both men and women compared to with men only (OR = 1.44; 95%CI:1.18-1.75), recent users of tobacco (OR = 2.20; 95%CI:1.92-2.52) and alcohol (OR = 2.84; 95%CI:2.52-3.20), and ever users of other drugs (OR = 1.69; 95%CI:1.44-1.99), independent of age, time and living situation.

CONCLUSIONS

Increasing rates of cannabis use and the association with concurrent tobacco and alcohol use in AYA females underscore the need to screen for unhealthy cannabis use, in addition to tobacco and alcohol, especially among inner-city AYA.

Cannabis use and co-use in tobacco smokers and non-smokers: prevalence and associations with mental health in a cross-sectional, nationally representative sample of adults in Great Britain, 2020

BACKGROUND AND AIMS

In Great Britain, cannabis and tobacco are commonly used substances, both independently and together. Use of either substance is associated with mental health problems, but prevalence of co-use within these populations is unknown. We aimed to (1) estimate prevalence of cannabis use, frequency of use and routes of administration (ROA) among tobacco smokers and non-smokers and (2) investigate mental health problems among non-users, tobacco-only, cannabis-only and co-users of both substances.

DESIGN

Cross-sectional national on-line survey (Action on Smoking and Health) fielded in February-March 2020.

SETTING

Great Britain.

PARTICIPANTS

Adults in Great Britain aged ≥ 18 years (n = 12 809) MEASUREMENTS: Tobacco use status [smoker (daily or non-daily) or non-smoker (never or ex-smoker)], cannabis use frequency (never to daily), detailed ROAs of cannabis, self-reported treatment for mental health disorders (depression, anxiety and any). Statistically weighted prevalence estimates were computed to ensure representativeness. Correlates were assessed using χ² tests and logistic regression.

FINDINGS

In Great Britain in 2020, 7.1% of the sample had used cannabis in the past year. Tobacco smokers had greater odds of using cannabis in the past year (21.9%) and using cannabis daily (8.7%) than non-smokers [past-year: 4.7%; adjusted odds ratio (aOR) = 10.07, 95% confidence interval (CI) = 8.4-12.0; daily: 0.7%; aOR = 24.6, 95% CI = 18.0-33.6)]. Co-administration with tobacco was common (46.2% of non-smokers, 80.8% of tobacco smokers). Co-users reported the highest prevalence of any treatment for mental health problems (54.2%) in comparison to cannabis-only (45.8%), tobacco-only (33.2%) and non-users (22.7%; all P ≤ 0.05).

CONCLUSION

Approximately one in 13 adults in Great Britain reports having used cannabis in the past year, approximately four times as many among cigarette smokers as non-smokers. Co-administration of cannabis and tobacco, via smoking, appears to be common, including among self-identified non-smokers. Mental health problems appear to be particularly common among dual users.

Alcohol, cannabis, and tobacco polysubstance use: A latent profile analysis of age of onset

BACKGROUND

Despite understanding the long-term risks associated with early substance use, less is known about the specific patterns of the age of onset (AO) across multiple substances and whether these patterns of early exposure are linked to substance use later in young adulthood. Consequently, the present study sought to (1) identify distinct classes regarding AO for alcohol, cannabis, and tobacco and (2) compare these classes on patterns of individual and simultaneous alcohol, cannabis, and tobacco use, other substance use, and mental health symptoms.

METHODS

Participants were 510 emerging adults (Mage = 21.35; 88.6% men) who reported past-year use of alcohol, cannabis, and tobacco.

RESULTS

Latent profile analysis was used to identify classes based on three indicators: AO for alcohol, cannabis, and tobacco. Results revealed that four classes best fit the data: Earliest AO for Alcohol (19.8%); Latest AO for Substances (6.5%); Late AO for Substances (67.8%); Earliest AO for Cannabis and Tobacco (5.9%). Classes varied on current patterns of individual substance use, co-use of substances, other illicit drug use, and mental health symptomology. The Latest AO of Substances class reported the lowest alcohol use, cannabis use, other illicit drug use, and mental health symptomology than the other classes. The Earliest AO for Alcohol and the Late AO of Substances reported a lower frequency of tobacco compared to the other classes. The Late AO of Substance class reported the highest past-year frequency of simultaneous alcohol and cannabis use.

CONCLUSIONS

The current study contributed to the larger polysubstance literature by identifying profiles that may signify risky patterns of use. Findings may help guide prevention and intervention work with adolescents and young adults.

Unknown population-level harms of cannabis and tobacco co-use: if you don't measure it, you can't manage it

BACKGROUND

Nationally representative data of cannabis-tobacco co-use have shown that these substances are closely entwined and have significant adverse health consequences, although population-level harms of co-use are largely unknown. Current epidemiological research does not assess co-use in a manner that has yielded the necessary data to draw conclusions regarding health effects. This has given rise to a hidden population of co-users who go under-served. Therefore, this paper has two aims: (1) to review new challenges in the collection of co-use data due to rapidly changing regulations of cannabis and nicotine products and (2) to provide recommendations for the terminology and assessment of co-use.

ARGUMENT

We argue that: (1) the prevalence of co-use is not being assessed accurately at a population level and (2) changes in legalization have created novel challenges, but without proper monitoring the impact on co-use will go undetected. We propose a three-level tiered set of recommendations for co-use assessments, which includes assessments of cannabis, tobacco and co-use metrics ranging from least burdensome (self-report of co-administered products) to most burdensome (assays, event-level data).

CONCLUSIONS

We propose that clinical studies begin to incorporate cannabis-tobacco co-use assessments to justify better their inclusion in clinical trials and national surveillance surveys. Integration of co-use assessments will aid in understanding the true impact on co-use of the changing cannabis and tobacco/nicotine regulatory environments. Co-use is prevalent and problematic, and the ability to make conclusions about its health outcomes is hindered by lack of nuance in data collection. If you do not measure it, you cannot manage it.

Predictors of cannabis and tobacco co-use in youth: exploring the mediating role of age at first use in the population assessment of tobacco health (PATH) study

Background

Adolescents often use substances such as tobacco and cannabis. Co-use of these substances can lead to physical, mental, and psychosocial difficulties beyond that which would be anticipated by simple additivity of their individual effects.

Methods

We aimed to examine the mediating role of age at first use of cannabis or tobacco (AU) between youth factors of internalizing, externalizing, and sensation seeking and two co-use outcomes (lifetime; last 30 days). Path analytic modeling using data from youth age 12–17 who had tried cannabis or tobacco at least once in their lives and participated in the Population Assessment of Tobacco Health (PATH) waves one and two (collected 2013–2015; n=3,847; approximately 46% female) study allowed us to examine these relationships.

Results

The lifetime use model indicated significant direct (internalizing (B = 0.18), externalizing (B = 0.30), sensation seeking (B = 0.15)) and indirect relationships (internalizing (B = 0.18), externalizing (B = 0.33), sensation seeking (B = 0.10)) between each of the three youth factors, the mediator (AU) and the lifetime co-use outcome (p < 0.05 for all). A direct relationship between AU and lifetime co-use was also observed (B = − 1.54). In the past 30-day use model, significant direct paths from AU (B = − 0.49) and sensation seeking (B = 0.06) to past 30-day use were present (p < 0.05 for all).

Discussion

Examination of mediation by AU in the relationships between youth factors and youth co-use of cannabis and tobacco is an important step in understanding these complex relationships. This study is strengthened by the use of a large, nationally representative sample, yet is limited by several factors, such as the use of a secondary dataset and the use of youth self-report.

Conclusions

Based on the findings, programs or interventions targeting youth factors of internalizing, externalizing, and sensation seeking as well as interventions aiming to stave off AU should promote decreased tobacco and cannabis co-use. Sensation seeking and AU appear to be the most influential factors and should be considered when developing and promoting prevention policies/programs for higher risk youth populations.

Early and Late Adolescent Factors that Predict Co-use of Cannabis with Alcohol and Tobacco in Young Adulthood

The changing legal landscape of cannabis in the USA has coincided with changes in how cannabis is used, including its co-use with other substances. This study analyzed 10 years of data from a diverse cohort of youth (N = 2429; 54% Hispanic, 16% Asian, 16% white, 3% black, 10% multiracial) to examine predictors in early and late adolescence of co-use of alcohol with cannabis (AC) and tobacco with cannabis (TC) at age 21. Two forms of co-use were examined: concurrent (use of both substances in past month) and sequential (use of one substance right after the other). Analyses focused on four predictor domains: individual (e.g., resistance self-efficacy), peer (e.g., time spent around peers who use), family (e.g., sibling use), and neighborhood (i.e., perceived alcohol and drug problems in neighborhood). For each co-use combination (AC or TC), we estimated parallel process piecewise latent growth models in a structural equation modeling framework using Mplus v8. The final AC and TC co-use models included all predictor variables from the four domains. Increases in positive expectancies and time spent around peers who use AC, as well as steeper decreases in resistance self-efficacy, were all related to a greater likelihood of AC co-use in young adulthood. Increases in sibling TC use and time spent around peers who use TC, as well as steeper decreases in resistance self-efficacy, were all related to a greater likelihood of TC co-use in young adulthood. Overall, findings highlight the importance of addressing peer influence in prevention programming during both early and late adolescence.

Twitter Surveillance at the Intersection of the Triangulum

INTRODUCTION

A holistic public health surveillance approach can help capture the public's tobacco and marijuana-related attitudes and behaviors. Using publicly available data from Twitter, this is one of the first studies to describe key topics of discussions related to each intersection (e-cigarette, combustible tobacco, and marijuana) of the Triangulum framework.

METHOD

Twitter posts (n=999,447) containing marijuana, e-cigarette and combustible tobacco terms were collected from January 1, 2018, to December 23, 2019. Posts to Twitter with co-occurring mentions of keywords associated with the Triangulum were defined as an intersection (e-cigarettes and combustible tobacco, combustible tobacco and marijuana, e-cigarettes and marijuana, and marijuana, e-cigarettes and combustible tobacco). Text classifiers and unsupervised machine learning was used to identify predominant topics in posts.

RESULTS

Product Features and Cartridges were commonly referenced at the intersection of e-cigarette and marijuana-related conversations. Blunts and Cigars and Drugs and Alcohol were commonly referenced at the intersection of combustible tobacco and marijuana-related discussions. Flavors and Health Risks were discussed at the intersection of e-cigarette and combustible-related conversations, while discussions about Illicit products and Health risks were key topics of discussion when e-cigarettes, combustible tobacco, and marijuana were referenced all together in a single post.

CONCLUSION

By examining intersections of marijuana and tobacco products, this study offers inputs for designing comprehensive FDA regulations including regulating product features associated with appeal, improving enforcement to curb sales of illicit products, and informing the FDA's product review and standards procedures for tobacco products that can be used with marijuana.

IMPLICATIONS

This study is the first to leverage the Triangulum framework and Twitter data to describe key topics of discussions at the intersection of e-cigarette, combustible tobacco, and marijuana. Real-time health communication interventions can identify Twitter users posting in the context of e-cigarettes, combustible tobacco, and marijuana by automated methods and deliver tailored messages. This study also demonstrates the utility of Twitter data for surveillance of complex and evolving health behaviors.

Cannabis Use, Cannabis Use Disorder, and Comorbid Psychiatric Illness: A Narrative Review

BACKGROUND

The landscape of attitudes, legal status and patterns of use of cannabis is rapidly changing in the United States and elsewhere. Therefore, the primary aim of this narrative review is to provide a concise overview of the literature on the comorbidity of cannabis use and cannabis use disorder (CUD) with other substance use and psychiatric disorders, and to use this information to accurately guide future directions for the field.

METHODS

A literature review of PubMed was conducted for studies relating to cannabis use, CUD, and a co-occurring psychiatric disorder. To provide an overview of representative data, the literature review focused on national-level, population-based work from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) and National Survey on Drug Use and Health (NSDUH) surveys. Considering rapidly changing cannabis laws, recent (past five-year) studies were addressed.

RESULTS

A strong body of literature shows associations between cannabis use and CUD with other drug use, psychosis, mood disorders, anxiety disorders, and personality disorders. The strongest evidence of a potential causal relationship exists between cannabis use and psychotic disorders. While some evidence shows potential directionality between cannabis use and mood and anxiety disorders, results are inconsistent. Studies have established higher rates of CUD among those with personality disorders, but little about the specifics of this relationship is understood.

CONCLUSIONS

Although the general population in the United States increasingly perceives cannabis to be a harmless substance, empirical evidence shows that cannabis use is associated both with CUD and comorbid psychiatric illness. However, there is mixed evidence regarding the role of cannabis in the etiology, course, and prognosis of a co-occurring disorder across all categories of psychiatric disorders. Future research should expand on the existing body of literature with representative, longitudinal data, in order to better understand the acute and long-term effects of cannabis on comorbid psychiatric illness.

Cannabis and Alcohol Co-Use in a Smoking Cessation Pharmacotherapy Trial for Adolescents and Emerging Adults

INTRODUCTION

The co-use of cannabis and alcohol among tobacco-using youth is common. Alcohol co-use is associated with worse tobacco cessation outcomes, but results are mixed regarding the impact of cannabis on tobacco outcomes and if co-use leads to increased use of non-treated substances. This secondary analysis from a youth smoking cessation trial aimed to (1) evaluate the impact of cannabis or alcohol co-use on smoking cessation, (2) examine changes in co-use during the trial, and (3) explore secondary effects of varenicline on co-use.

METHODS

The parent study was a 12-week, randomized clinical trial of varenicline for smoking cessation among youth (ages 14-21, N = 157; Mage = 19, 40% female; 76% White). Daily cigarette, cannabis, and alcohol use data were collected via daily diaries during treatment and Timeline Follow-back for 14 weeks post-treatment.

RESULTS

Baseline cannabis co-users (68%) had double the odds of continued cigarette smoking throughout the trial compared with noncannabis users, which was pronounced in males and frequent cannabis users. Continued smoking during treatment was associated with higher probability of concurrent cannabis use. Baseline alcohol co-users (80%) did not have worse smoking outcomes compared with nonalcohol users, but continued smoking was associated with higher probability of concurrent drinking. Varenicline did not affect co-use.

CONCLUSIONS

Inconsistent with prior literature, results showed that alcohol co-users did not differ in smoking cessation, whereas cannabis co-users had poorer cessation outcomes. Youth tobacco treatment would benefit from added focus on substance co-use, particularly cannabis, but may need to be tailored appropriately to promote cessation.

IMPLICATIONS

Among youth cigarette smokers enrolled in a pharmacotherapy evaluation clinical trial, alcohol and/or cannabis co-use was prevalent. The co-use of cannabis affected smoking cessation outcomes, but more so for males and frequent cannabis users, whereas alcohol co-use did not affect smoking cessation. Reductions in smoking were accompanied by concurrent reductions in alcohol or cannabis use. Substance co-use does not appear to affect all youth smokers in the same manner and treatment strategies may need to be tailored appropriately for those with lower odds of smoking cessation.

Nicotine and Toxicant Exposure Among Concurrent Users (Co-Users) of Tobacco and Cannabis

BACKGROUND

Smoking cannabis may potentially increase exposure to numerous toxic chemicals that are commonly associated with tobacco use. There is a paucity of data related to toxicant exposures among concurrent users of tobacco and cannabis (co-users).

METHODS

Data are from the Population Assessment of Tobacco and Health Study Wave 1 Biomarker Restricted-Use Files. Analyses focused on adults who provided urine samples (N = 5859). Urine samples were analyzed for biomarkers of exposure to nicotine, tobacco-specific nitrosamines, polycyclic aromatic hydrocarbons, and volatile organic compounds. Using weighted linear regression, we compared adjusted geometric mean concentrations of 15 biomarkers between user groups of various tobacco product types according to their self-reported past 30-day cannabis use.

RESULTS

Past 30-day cannabis use was similar across various types of tobacco product use subgroups (range: 13%-23%) and significantly more common compared to non-tobacco users (1.0%; p < .001). Across all groups of tobacco users, those who co-used cannabis exhibited significantly higher concentrations of the biomarker of exposure to acrylonitrile (CYMA) compared to non-cannabis users (by 39%-464%). Tobacco-cannabis co-users also showed significantly elevated levels of the biomarker of exposure to acrylamide (AAMA) compared to exclusive tobacco users, and significantly higher exposure to many polycyclic aromatic hydrocarbons (including fluorene and pyrene).

CONCLUSIONS

Co-users exhibited higher concentrations for biomarkers of exposure to many combustion byproducts, compared to exclusive tobacco users. More robust measurements of cannabis use can address potential confounding in assessments of exposures to tobacco-related constituents, and potential health effects resulting from co-use.

IMPLICATIONS

With disproportionately greater rates of cannabis use occurring among tobacco users, it is critical to consider how concurrent cannabis use may influence health-related outcomes among smokers. Our findings suggest potential additive toxicant exposures among co-users of tobacco and cannabis. Lack of consideration and measurement of cannabis use in assessing tobacco-related exposures may confound estimates thought to be attributable to tobacco, particularly for non-specific biomarkers. Assessing tobacco and cannabis use in tandem will allow for more precise measurement of outcomes related to one or both substances, and can provide additional information on potential health effects related to co-use.

Predictors of marijuana vaping onset and escalation among young adults

BACKGROUND

Little is known about factors that influence marijuana vaping among young people. We examined cigarette, e-cigarette and marijuana use experiences, social network characteristics and exposure to direct e-cigarette marketing as predictors of marijuana vaping initiation and escalation.

METHODS

One-year prospective data were collected between 2017 and 2019 from 2327 young adults (Mean age = 21.2; SD = 2.1; 54 % women) attending 2-year and 4-year colleges in Hawaii.

RESULTS

Among participants who were never marijuana users at baseline, being a dual user of cigarette and e-cigarette at baseline was the strongest predictor of marijuana vaping initiation, followed by baseline cigarette-only and e-cigarette-only use. Higher prevalence of regular marijuana users in one's social networks, but not e-cigarette users or cigarette smokers, significantly predicted marijuana vaping initiation a year later. Among baseline current e-cigarette users and lifetime marijuana users, higher presence in social networks of individuals who frequented vape shops at baseline was a significant predictor of increased current marijuana vaping at one-year follow-up.

CONCLUSIONS

Dual use of cigarette and e-cigarette and greater presence in social networks of marijuana users and people who frequent vape shops appear to be robust predictors of marijuana vaping onset and escalation among young adults. In addition to promoting e-cigarette use prevention/cessation, efforts to control marijuana vaping may need to consider promoting smoking prevention/cessation and the effects of increasing prevalence of marijuana use.

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.

Change over time in adolescent smoking, cannabis use and their association: findings from the School Health Research Network in Wales

Background

While tobacco smoking has declined among UK youth in recent decades, cannabis use has begun to show some growth. Given their interrelationship, growth in cannabis use may act as a barrier to continued reduction in youth smoking. This paper assesses recent tobacco and cannabis use trends in Wales, and their association, to explore whether change in cannabis use might have impacted youth tobacco smoking prevalence.

Methods

Repeat cross-sectional data on tobacco and cannabis use were obtained from biennial Welsh Student Health and Wellbeing surveys between 2013 and 2019. Data were pooled and analysed using logistic regression with adjustment for school-level clustering.

Results

No change in regular youth tobacco smoking was observed between 2013 and 2019. In contrast, current cannabis use increased during this time, and cannabis users had significantly greater odds of regular tobacco smoking. After adjusting for change in cannabis use, a significant decline in youth tobacco smoking was observed (OR 0.95; 95% confidence intervals: 0.92, 0.97).

Conclusion

Recent growth in cannabis use among young people in Wales may have offset prospective declines in regular tobacco smoking. Further reductions in youth smoking may require more integrated policy approaches to address the co-use of tobacco and cannabis among adolescents.

Youth Exposure to Marijuana Advertising in Oregon's Legal Retail Marijuana Market

Introduction

Research from tobacco and alcohol markets suggests advertising exposure is associated with perceptions of lower risk and increased use among young people. Limiting marketing may be a regulatory approach to prevent potential negative effects of retail marijuana legalization on youth use. This study assessed marijuana advertising exposure reported by youths in Oregon after the start of retail marijuana sales in October 2015.

Methods

Data from a 2017 school-based survey of Oregon 8th (N = 14,852) and 11th (N = 11,895) graders were used to characterize marijuana advertising exposure. Subgroup differences in reported exposure were assessed by using Pearson χ² tests and multiple logistic regression.

Results

About three-quarters of 8th (72.2%) and 11th graders (78.1%) in Oregon reported seeing marijuana advertising in the past month. Youths most frequently reported seeing advertising on storefronts and online, and odds of exposure were significantly higher for girls; lesbian, gay, or bisexual youths; current marijuana users; 8th graders living with an adult who uses marijuana; and youths in school districts with a closer average proximity to retail marijuana stores.

Conclusion

Reporting exposure to marijuana advertising is common among youths in Oregon’s legal retail market. Oregon and other states working to prevent youth marijuana use may want to examine how well their rules are working to prevent youth exposure. Although some sources of youth advertising exposure may be difficult to regulate and enforce (eg, online), others may be within the purview of state authority (eg, billboards, storefronts) depending on state-specific interpretation of free speech protections.

Developmental Trajectories of Tobacco/Nicotine and Cannabis Use and Patterns of Product Co-use in Young Adulthood

Introduction

Concurrent co-use of tobacco/nicotine and cannabis (T/C) products is common among young people and may increase risks for negative health and psychosocial outcomes, but little is known about developmental patterns of T/C co-use. This study aimed to identify distinct trajectory classes of concurrent T/C co-use from ages 16 to 21 and compare groups on T/C co-use behaviors in young adulthood.

Methods

Participants (n = 2497) reported T/C use on annual online surveys from 2015 to 2019 (ages 16-22). We used parallel process growth mixture models to model simultaneous trajectories of past-month cigarette, e-cigarette, smokeless tobacco, and cannabis use and identify latent classes of T/C trajectories. Classes were then compared on types and number of T/C products used and types of T/C co-use in young adulthood.

Results

Models revealed 4 T/C classes: Low/No T/C Use, Early Concurrent T/C Co-use, Late Concurrent T/C Co-use, and Tobacco Quitters/Cannabis Maintainers. Compared to other classes, the Early Concurrent T/C Co-use group-individuals with rapid progression to concurrent T/C co-use during adolescence-were more likely to report poly-tobacco use, poly-cannabis use, same-occasion sequential T/C co-use and T/C co-administration (ie, mixing T/C) of both combustible and vaping products in young adulthood.

Conclusion

Early progression to concurrent T/C co-use in adolescence is prospectively linked to poly-product use and co-use of T/C products in young adulthood. Prevention efforts targeting co-use of T/C products in adolescence may help to reduce riskier patterns of T/C use and co-use in young adulthood.

Co-occurring Use of Cannabis and Tobacco and the Presence of Acute Respiratory Symptoms among Young Adult Light and Intermittent Smokers

BACKGROUND

Cannabis use and intermittent smoking are becoming increasingly prevalent among young adults. Thus, identifying health consequences of co-occurring use of these substances represents an emerging research priority. Purpose/Objectives: This study evaluated the relationship between tobacco/cannabis co-use and acute symptoms of respiratory illness among young adult intermittent smokers. We hypothesized that tobacco/cannabis co-use would be more strongly associated with respiratory symptoms relative to use of neither or one product. Methods: A secondary analysis of a three-year observational study was conducted. Non-daily smokers (n = 563) aged 18-24 were recruited via social media and completed electronic surveys at baseline and annually for two years, producing three total assessments. Past-two-week use of tobacco and cannabis was measured at each assessment, as was severity of six acute respiratory symptoms. The respiratory measure was dichotomized to indicate the presence or absence of symptoms. Results: Tobacco/cannabis co-use decreased from 54.8% at baseline to 43.4% at year two (p < .001). Mean respiratory symptoms also declined significantly over time (ps < .05). At each timepoint, co-use was more strongly associated with presence of respiratory symptoms than the use of neither product (aORs = 2.73-4.39, ps ≤ .013). Co-users were also 38%-183% more likely to endorse the presence of respiratory symptoms than single product users at each timepoint (aORs = 1.38-2.83, ps = .023-.212). Conclusions/Importance: Although co-occurring use of tobacco and cannabis by young adults may represent experimental use of multiple substances, it may also promote or exacerbate acute symptoms of respiratory illness. Further exploration with more granular patterns of co-use and across different routes of administration is warranted.

Blunt and Non-Blunt Cannabis Use and Risk of Subsequent Combustible Tobacco Product Use Among Adolescents

INTRODUCTION

Cannabis-including blunts (cannabis rolled in tobacco-containing cigar casing) -is commonly the first substance used among adolescents and may increase the likelihood of subsequent initiation of combustible tobacco products.

AIMS AND METHODS

Data were pooled from two prospective studies of adolescents in California and Connecticut (total N = 4594). Logistic regression models assessed the association of baseline ever blunt use and ever non-blunt cannabis use (vs. never cannabis use) with subsequent initiation of any combustible tobacco-only product (ie, cigarettes, cigars, or cigarillos) by 1-year follow-up after adjustment for demographic characteristics and other tobacco product use at baseline. We also assessed whether estimates differed by prior e-cigarette or hookah use at baseline.

RESULTS

Among never combustible tobacco-only product users (N = 2973), 221 (7.4%) had ever used a blunt and 114 (3.8%) had ever used only non-blunt cannabis at baseline. Blunt use (adjusted odds ratio [AOR] = 1.98, 95% confidence interval [CI]: 1.30 to 3.01) and non-blunt cannabis use (AOR = 2.38, 95% CI: 1.41 to 4.00) were independently associated with greater odds of combustible tobacco-only product initiation by follow-up. Among those who had not tried e-cigarettes or who had not tried hookah, blunt use and non-blunt cannabis use were associated with significantly increased odds of combustible tobacco product initiation; among those who had tried e-cigarettes or hookah, the association was not significant.

CONCLUSIONS

We found blunt and non-blunt cannabis use to be associated with subsequent combustible tobacco-only product initiation, particularly among adolescents who had not also tried other products containing nicotine.

IMPLICATIONS

Adolescent-focused tobacco prevention efforts should consider incorporating cannabis products, including blunts. More research is needed to understand how blunt use and cannabis use more broadly are associated with initiation of tobacco products.

Digital health for assessment and intervention targeting tobacco and cannabis co-use

Purpose of review

This article aims to summarize current research on digital health for assessment and intervention targeting tobacco and cannabis co-use and to answer the following questions: Which digital tools have been used? Which populations have been targeted? And what are implications for future research?

Recent findings

Ecological Momentary Assessment (EMA) via text messages or interactive voice response calls has been used to capture co-use patterns within a time window or co-administration of both substances via blunts among young adults. Feasibility of multicomponent interventions targeting dual cessation of both substances among adult co-users with cannabis use disorder, delivered via smartphone apps, online, and computer modules has been demonstrated.

Summary

Digital tools, particularly those using EMAs and mobile sensors, should be expanded to assess co-use of emerging tobacco and cannabis products. Digital cessation interventions should be tailored to different groups of co-users and address specific mechanisms underlying different co-use patterns.

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.

Quantitative biochemical screening for marijuana use and concordance with tobacco use in urban adolescents

BACKGROUND

Assessing the prevalence and level of exposure (dose) of tobacco and marijuana use is important in studies of harm from use of these substances. We used biochemical analysis of urine to quantitatively assess exposure to nicotine and delta 9-tetrahydrocannabinol (THC) in adolescents receiving medical care in a public hospital METHODS: Participants were 686 adolescents between 12 and 21 years old seen at Zuckerberg San Francisco General Hospital between 2012 and 2014. Urine samples were assayed using high sensitivity liquid chromatographic assays for cotinine, a major metabolite of nicotine, and 11-nor-9-carboxy-delta 9-THC (THC-COOH), a major metabolite of THC. A commonly used immunoassay screen for THC-COOH was also performed.

RESULTS

The THC-COOH immunoassay substantially underestimated THC exposure, as measured with the high sensitivity assay. THC use was detected in 25% of participants, with higher prevalence with increasing age and in non-Hispanic blacks. Active tobacco smokers had an 80% prevalence of THC use (odds ratio for cigarette smoking predicting THC use 13.2). Urine cotinine and THC-COOH were significantly correlated (r = 0.60).

CONCLUSIONS

The use of a high sensitivity chromatographic urine assay provides a much more complete picture of adolescent tobacco use compared to a commonly used immunoassay. The immunoassay provides high specificity but moderate sensitivity. We confirm high concordance of tobacco and marijuana use and the high predictive value of cigarette smoking in predicting marijuana use, and provide novel data on the quantitative correlation between level of exposure to nicotine and THC. Quantitative screening of nicotine and THC exposure may enhance our understanding of addiction and harm from single and dual product use.

Cannabis and tobacco use and co-use: Trajectories and correlates from early adolescence to emerging adulthood

BACKGROUND

Cannabis and tobacco co-use is a growing concern, yet little is known about its developmental course or associated outcomes during emerging adulthood. This study examines developmental trajectories of cannabis and tobacco co-use from adolescence to emerging adulthood, associations of co-use trajectories with four domains of functioning, and differences across racial/ethnic groups.

METHODS

Survey data come from a racially/ethnically diverse and predominantly California-based cohort that completed 10 surveys from 2008 (wave 1: mean age 11.5; n = 6,509) to 2018 (wave 10: mean age 20.7; n = 2,429). Co-use was defined as use of both cannabis and tobacco (cigarettes or smokeless tobacco) in the past 30 days. Trajectories of use were examined using latent growth modeling in a structural equation modeling framework.

RESULTS

Prevalence of cannabis and tobacco co-use increased from 0.3% at wave 1 to 9.5% at wave 10, with average probabilities of co-use higher among non-Hispanic white versus Hispanic or Asian participants. Higher average probability of co-use was associated with greater delinquency, more mental health symptoms, and poorer physical health during emerging adulthood. Higher rate of change in the probability of co-use over time was associated with greater delinquency, but better social functioning and less physical ailments. There was some evidence of racial/ethnic disparities in functioning, even at similar levels of co-use.

CONCLUSIONS

Cannabis and tobacco co-use deserves greater attention, especially regarding its effects on functioning during emerging adulthood. Results also emphasize the need for future research to focus on racial/ethnic disparities related to co-use and associated outcomes.

Past 30-day co-use of tobacco and marijuana products among adolescents and young adults in California

BACKGROUND

Limited research among adolescents and young adults (AYA) has assessed tobacco and marijuana co-use in light of specific products. We examined the patterns of past 30-day co-use of tobacco and marijuana products, and the product-specific associations among past 30-day use of these substances.

METHODS

Data from three school-based convenience samples of California AYA (aged 15-22) (Sample 1 = 3008; Sample 2 = 1419; Sample 3 = 466) were collected during 2016-2017. Proportions of past 30-day co-use of tobacco (e-cigarettes, cigarettes, hookah, cigars) and marijuana (combustible, vaporized, edible, blunt) were estimated. Multivariable logistic regression analyses examined associations between use of each tobacco and marijuana product for individual samples, then the pooled analysis calculated combined ORs.

RESULTS

In the three samples, 7.3-11.3% of participants reported past 30-day co-use. Combinations of e-cigarettes or cigarettes and combustible marijuana were the most common co-use patterns. Past 30-day use of e-cigarettes or cigarettes (vs. non-use) increased the odds of past 30-day use of all marijuana products [e-cigarettes: ORs (95%CI) ranging from 2.5 (1.7, 3.2) for edible marijuana to 4.0 (2.8, 5.2) for combustible marijuana; cigarettes: from 3.2 (2.1, 4.2) for vaporized marijuana to 5.5 (3.8, 7.3) for combustible marijuana]. Past 30-day use of hookah or cigars was positively associated with past 30-day use of three of four marijuana products, except for hookah and vaporized marijuana, and for cigars and combustible marijuana.

CONCLUSIONS

Given various co-use patterns and significant associations among tobacco and marijuana products, interventions targeting AYA should address co-use across the full spectrum of specific products for both substances.

Consequences of Perinatal Cannabis Exposure

Cannabis exposure during the perinatal period results in varied and significant consequences in affected offspring. The prevalence of detrimental outcomes of perinatal cannabis exposure is likely to increase in tandem with the broadening of legalization and acceptance of the drug. As such, it is crucial to highlight the immediate and protracted consequences of cannabis exposure on pre- and postnatal development. Here, we identify lasting changes in neurons' learning flexibility (synaptic plasticity) and epigenetic misregulation in animal models of perinatal cannabinoid exposure (using synthetic cannabinoids or active components of the cannabis plant), in addition to significant alterations in social behavior and executive functions. These findings are supported by epidemiological data indicating similar behavioral outcomes throughout life in human offspring exposed to cannabis during pregnancy. Further, we indicate important lingering questions regarding accurate modeling of perinatal cannabis exposure as well as the need for sex- and age-dependent outcome measures in future studies.

Alcohol, tobacco, and marijuana consumption is associated with increased odds of same-day substance co- and tri-use

BACKGROUND

Little is known about event-level patterns of marijuana co- or tri-use with alcohol and tobacco. Thus, the study goal was to examine patterns of same-day alcohol, cigarette, and marijuana co- and tri-use at the individual level in non-treatment-seeking alcohol users.

METHODS

Participants (N = 551) completed an in-person interview for alcohol, cigarette, and marijuana use over the previous 30 days, and the event-level substance use patterns of n = 179 participants who reported using each of these substances at least once per month were analyzed.

RESULTS

The use of alcohol, marijuana, or cigarettes independently increased the probability of subsequent, simultaneous co-use of one of the two remaining substances. The co-use of alcohol with cigarettes and marijuana with cigarettes produced generally additive effects on the odds of same day tri-use of marijuana and alcohol, respectively. Conversely, the co-use of alcohol and marijuana produced sub-additive effects on likelihood of cigarette use. Sex moderated several of the observed patterns of co- and tri-use: the relationship between alcohol or cigarette use predicting marijuana co-use was stronger in men, whereas the observed additive relationships between drug co-use leading to tri-use was stronger in women.

CONCLUSIONS

The presented results may aid in the understanding of how simultaneous co-use of marijuana with alcohol and/or tobacco relates to the etiology, maintenance, and treatment of comorbid and trimorbid substance use disorder. Replication and extension of the results in treatment seeking populations using more fine-grained analysis approaches, e.g. ecological momentary assessment, is needed.

Tobacco and cannabis co-use: Drug substitution, quit interest, and cessation preferences

The co-use of tobacco and cannabis is a common practice worldwide and carries with it substantial public health burden. Few interventions exist that target both substances and little is known about quit interest, treatment preferences, and drug substitution during past cessation attempts, which is critical to guide the development of treatment strategies. The goal of this study was to provide descriptive information regarding quit interest, treatment preferences, and perceived drug substitution among adult (age 18 +) cannabis-tobacco co-users. Participants (N = 282) from two independent survey samples (recruited from Amazon Mechanical Turk) from across the United States were combined. Among all participants, 57% were female, 79% were White, and average age was 33.31 (SD = 9.54) years old. Approximately 80% had tried to quit smoking cigarettes at least once, while 40% had tried to quit using cannabis at least once. Of those who tried to quit, 50% self-reported a perceived increase in their cannabis use during tobacco cessation and 62% self-reported a perceived increase in their tobacco use during cannabis cessation. Average quit interest (10-point scale) for cannabis was 2.39 (SD = 2.35) and for tobacco was 7.07 (SD = 2.90). Results of this study suggest that tobacco use should be addressed among cannabis-tobacco co-users, but interventions should consider lack of interest in cannabis cessation. Reduction-based strategies for cannabis use appear to be more acceptable to this nontreatment-seeking, co-using population. Drug substitution during quit attempts for one substance should be further explored as an important treatment consideration. (PsycINFO Database Record (c) 2019 APA, all rights reserved).