Past 15-year trends in adolescent marijuana use: Differences by race/ethnicity and sex

Disentangling the lasting effects of adolescent cannabinoid exposure

Cannabis is the most widely used illicit substance among adolescents, and adolescent cannabis use is associated with various neurocognitive deficits that can extend into adulthood. A growing body of evidence supports the hypothesis that adolescence encompasses a vulnerable period of development where exposure to exogenous cannabinoids can alter the normative trajectory of brain maturation. In this review, we present an overview of studies of human and rodent models that examine lasting effects of adolescent exposure. We include evidence from meta-analyses, longitudinal, or cross-sectional studies in humans that consider age of onset as a factor that contributes to the behavioral dysregulation and altered structural or functional development in cannabis users. We also discuss evidence from preclinical rodent models utilizing well-characterized or innovative routes of exposure, investigating the effects of dose and timing to produce behavioral deficits or alterations on a neuronal and behavioral level. Multiple studies from both humans and animals provide contrasting results regarding the magnitude of residual effects. Combined evidence suggests that exposure to psychoactive cannabinoids during adolescence has the potential to produce subtle, but lasting, alterations in neurobiology and behavior.

Past 6-Year Trends in Current Alcohol Use among Cyberbullied Adolescents

Most of the research on alcohol use and being cyberbullied has focused on the correlation between the two. Less is known about the recent epidemiology of adolescent current alcohol use. Objective: To describe the trends in current alcohol use among adolescence that self-report being cyberbullied across sex and racial/ethnic groups. Methods: The data from the present study came from the national Youth Risk Behavior Surveys (YRBS) from 2011 to 2017. We estimated the prevalence of current alcohol use across years by biological sex and race/ethnicity. Further we tested for linear and quadratic trends. Results: We observed statistically significant decreases in alcohol use cyberbullied (b= -0.12, p < 0.00), and non-cyberbullied individuals (b=-0.15, p < 0.00). Further, we found significant decreases for cyberbullied males (b= -0.10, p < 0.01), females (b= -0.17, p < 0.01) blacks (b= -0.39, p < 0.00), and Hispanics (b= -0.17, p < 0.01). Whites and other races were did not have a significant change. We also found significant decreases for cyberbullied white males and females, black males (b=-0.46, p < 0.03) and females (b= -0.37, p < 0.02), Hispanic males (b=-0.33, p < 0.00). White males and females and other males and females did not have significant changes in alcohol use prevalence. Conclusions: Consistent with national trends, alcohol use among adolescents is decreasing. The decrease is occurring within those that are being cyberbullied. Further research with different data are necessary to further validate these results.

Attitudes, Subjective Norms, and Perceived Behavioral Control Associated with Age of First Use of Cannabis among Adolescents

BACKGROUND

Prevention of early age initiation of cannabis use is a national priority, highlighting the importance of identifying cannabis-specific attitudes, norms, and perceived behavioral control in relation to initiation age.

METHODS

Data were from the NEXT Generation Health Study, a national longitudinal sample of US adolescents followed from 10th grade (N = 1850). Cannabis-specific attitudes, norms, and perceived behavioral control were assessed at 10th grade. Age of first use was reported retrospectively 2-3 years after high-school and participants were categorized as early initiators (<14 years; 3.8%), high-school (HS) initiators (14-18 years; 35.6%), post-HS initiators (>18 years; 8.3%), or never users (52.3%).

RESULTS

Relative to never users, early initiators were more likely to endorse pro-use attitudes (AOR [adjusted odds ratio] = 2.39, 95% confidence interval [CI] = 1.27-4.50), less disapproving parental attitudes toward use (AOR = 2.50, 95% CI = 1.45-4.28), higher cannabis use among friends (AOR = 3.81, 95% CI = 2.21-6.60), and higher ease of access (AOR = 2.10, 95% CI = 1.14-3.87); HS initiators were similarly more likely to report less disapproving attitudes toward use (AOR = 1.55, 95% CI = 1.25-1.91), higher cannabis use among friends (AOR = 2.81, 95% CI = 2.18-3.65), and higher ease of access (AOR = 1.66, 95% CI = 1.21-2.28).

CONCLUSIONS

Earlier cannabis initiation was associated with more favorable cannabis attitudes, subjective norms, and perceived behavioral control, highlight these variables as potential intervention targets.

Changes in cannabis use according to socioeconomic status among Finnish adolescents from 2000 to 2015

BACKGROUND

Despite reduced sanctions and more permissive attitudes toward cannabis use in the USA and Europe, the prevalences of adolescent cannabis use have remained rather stable in the twenty-first century. However, whether trends in adolescent cannabis use differ between socioeconomic groups is not known. The aim of this study was to examine trends in cannabis use according to socioeconomic status among Finnish adolescents from 2000 to 2015.

METHODS

A population-based school survey was conducted biennially among 14-16-year-old Finns between 2000 and 2015 (n = 761,278). Distributions for any and frequent cannabis use over time according to socioeconomic adversities were calculated using crosstabs and chi-square test. Associations between any and frequent cannabis use, time, and socioeconomic adversities were studied using binomial logistic regression results shown by odds ratios with 95% confidence intervals.

RESULTS

At the overall level, the prevalences of lifetime and frequent cannabis use varied only slightly between 2000 and 2015. Cannabis use was associated with socioeconomic adversities (parental unemployment in the past year, low parental education, and not living with both parents). The differences in any and frequent cannabis use between socioeconomic groups increased significantly over the study period.

CONCLUSIONS

Although the overall changes in the prevalence of adolescent cannabis use were modest, cannabis use increased markedly among adolescents with the most socioeconomic adversities. Socioeconomic adversities should be considered in the prevention of adolescent cannabis use.

Analysis of US Teen Driving After Using Marijuana, 2017

This cross-sectional study examines the prevalence of and factors associated with driving after using marijuana among US adolescents.

TBI as a Risk Factor for Substance Use Behaviors: A Meta-analysis

OBJECTIVE

To quantify the relationship between substance use behaviors before and after traumatic brain injury (TBI), to identify populations that may benefit more from targeted interventions to reduce the effect of substance use on TBI recovery, and to establish areas for further study.

DATA SOURCES

Studies were identified via literature searches using MEDLINE, PsychInfo, PsychArticles, PubMed, and GoogleScholar (published before January 2019), as well as reference section reviews and forward searches. Searches were conducted using search terms for TBI and substance use behaviors.

STUDY SELECTION

Studies were included if they (1) contained both a measure of TBI and a measure of substance use behaviors; (2) reported an effect size representing the relationship between substance use behaviors before and after TBI, compared TBI vs non-TBI groups on substance use behaviors controlling for pre-TBI substance use, or compared groups with differing TBI severity on subsequent substance use behaviors controlling for pre-TBI substance use; (3) were written in English; and (4) were human subjects research. Studies examining effects of substance use intervention for people sustaining TBI were excluded from this study.

DATA EXTRACTION

Study variables included substance use behaviors, TBI severity, time since TBI, military status, age, race, and sex.

DATA SYNTHESIS

Substance use behaviors had a small but statistically significant decrease after moderate-severe TBI. After moderate-severe TBI, there was a statistically significant decline in both substance use (d=-0.29, P<.01) and negative substance use consequences (d=-0.67, P=.01). There was no significant change in substance use behaviors after mild TBI.

CONCLUSIONS

Substance use behaviors had a small decrease after moderate to severe TBI and no significant change after mild TBI. Study findings suggest the need for accurate assessment to identify those at greatest risk for problematic substance use behaviors after TBI.

Sex-Related Differences in Adolescent Cannabis Use: Influences of School Context and School Connectedness

BACKGROUND

Boys use cannabis at a younger age and more frequently than girls. It has been suggested these sex differences might vary according to students' relationship to school. We explored whether the association between sex and adolescents' cannabis use varies among schools and according to students' school connectedness.

METHODS

The study population consisted of all students from 11 secondary schools in the greater Québec City area. The sample included 6185 respondents in years 1 to 5 at the secondary level (equivalent to grades 7-11). Study outcomes were monthly cannabis use and early cannabis use.

RESULTS

The association between sex and monthly cannabis use varied significantly among schools after controlling for students' main characteristics and school socioeconomic environment. We found a statistically significant modifying effect of school connectedness on the association between sex and monthly cannabis use. For early cannabis use, we found no modifying effect of school connectedness nor any association with sex.

CONCLUSIONS

Measures to reduce adolescents' cannabis use could be better adapted to local context and more tailored to specific higher-risk groups. School connectedness is a protective factor for cannabis use, although this effect appears stronger for girls than boys.

Race, cannabis and the Canadian war on drugs: An examination of cannabis arrest data by race in five cities

BACKGROUND

The enforcement of drug laws in the United States has been heavily racialized. A substantial proportion of individuals arrested and prosecuted for drug possession in America are Black and Latino, despite similar rates of drug use across racial groups. Due to a lack of access to racially disaggregated criminal justice data, little is known about how race influences drug law enforcement in Canada.

METHODS

We conducted an analysis of cannabis arrest data obtained from police services in five Canadian cities (Vancouver, Calgary, Regina, Ottawa, Halifax) to determine whether racial differences exist in rates of arrest for minor cannabis possession in Canada.

RESULTS

With just one exception, we find that both Black and Indigenous people are over-represented amongst those arrested for cannabis possession across the five cities examined.

CONCLUSIONS

Canadian cannabis legalization lacks measures to redress the racialized harms caused by the war on drugs because the full extent of these harms remains largely unknown. Broader collection and dissemination of disaggregated criminal justice data is needed in the Canadian context in order to inform criminal justice and social policy.

Sex and Gender Differences in the Effects of Novel Psychoactive Substances

Sex and gender deeply affect the subjective effects and pharmaco-toxicological responses to drugs. Men are more likely than women to use almost all types of illicit drugs and to present to emergency departments for serious or fatal intoxications. However, women are just as likely as men to develop substance use disorders, and may be more susceptible to craving and relapse. Clinical and preclinical studies have shown important differences between males and females after administration of “classic” drugs of abuse (e.g., Δ9-tetrahydrocannabinol (THC), morphine, cocaine). This scenario has become enormously complicated in the last decade with the overbearing appearance of the new psychoactive substances (NPS) that have emerged as alternatives to regulated drugs. To date, more than 900 NPS have been identified, and can be catalogued in different pharmacological categories including synthetic cannabinoids, synthetic stimulants (cathinones and amphetamine-like), hallucinogenic phenethylamines, synthetic opioids (fentanyls and non-fentanyls), new benzodiazepines and dissociative anesthetics (i.e., methoxetamine and phencyclidine-derivatives). This work collects the little knowledge reached so far on the effects of NPS in male and female animal and human subjects, highlighting how much sex and gender differences in the effects of NPS has yet to be studied and understood.

Marijuana Legalization and Youth Marijuana, Alcohol, and Cigarette Use and Norms

INTRODUCTION

Rates of adolescent substance use have decreased in recent years. Knowing whether nonmedical marijuana legalization for adults is linked to increases or slows desirable decreases in marijuana and other drug use or pro-marijuana attitudes among teens is of critical interest to inform policy and promote public health. This study tests whether nonmedical marijuana legalization predicts a higher likelihood of teen marijuana, alcohol, or cigarette use or lower perceived harm from marijuana use in a longitudinal sample of youth aged 10-20 years.

METHODS

Data were drawn from the Seattle Social Development Project-The Intergenerational Project, an accelerated longitudinal study of youth followed both before (2002-2011) and after nonmedical marijuana legalization (2015-2018). Analyses included 281 youth surveyed up to 10 times and living in a state with nonmedical marijuana legalization between 2015 and 2018 (51% female; 33% white, 17% African American, 10% Asian/Pacific Islander, and 40% mixed race or other).

RESULTS

Multilevel modeling in 2019 showed that nonmedical marijuana legalization predicted a higher likelihood of self-reported past-year marijuana (AOR=6.85, p=0.001) and alcohol use (AOR 3.38, p=0.034) among youth when controlling birth cohort, sex, race, and parent education. Nonmedical marijuana legalization was not significantly related to past-year cigarette use (AOR=2.43, p=0.279) or low perceived harm from marijuana use (AOR=1.50, p=0.236) across youth aged 10-20 years.

CONCLUSIONS

It is important to consider recent broad declines in youth substance use when evaluating the impact of nonmedical marijuana legalization. States that legalize nonmedical marijuana for adults should increase resources for the prevention of underage marijuana and alcohol use.

Polysubstance use among frequent marijuana users: an examination of John Henryism Active Coping, psychiatric symptoms, and family social support among African American incarcerated men

Incarcerated African American men who use marijuana are vulnerable to polysubstance use, which is associated with greater risk for negative health and psychosocial outcomes than marijuana use alone. It is imperative to understand risk and protective factors for polysubstance use among this vulnerable population to inform the development of culturally tailored substance use interventions. The current study examined the association between John Henryism Active Coping (JHAC), family social support, psychiatric symptoms, and polysubstance use among African American incarcerated men who frequently use marijuana. Results indicated that higher John Henryism Active Coping (JHAC) is associated with decreased likelihood of engaging in polysubstance use, while psychiatric symptoms are associated with increased likelihood of polysubstance use. Incorporating elements of JHAC into concurrent mental health and substance use treatment may reduce risk for overdose and reincarceration among African American incarcerated men upon release into the community.

Illicit drug use by mothers and their daughters in Australia: A comparison of two generations

BACKGROUND

While recent decades have witnessed an increase in the use of illicit drugs in Australia, the extent to which the types of drugs used has changed over a generation of young women has not been documented.

METHODS

Data are from a prospective birth cohort study. Mothers were recruited in early pregnancy (1981-83) and then they and their child were followed up, with mothers interviewed 27 years (2008-2011), and daughters 30 years (2010-14), after the birth. At these most recent interviews both mothers and daughters were administered the Composite International Diagnostic Interview (CIDI III). Comparisons are for mothers and daughters separated by a 25 year period. For this study, we compare levels of lifetime use of a range of illicit drugs and drug use disorders reported by mothers and their daughters (N = 998 mother/daughter pairs) with adjustment for family income, marital status, education and occupation.

RESULTS

There has been a generational increase in the use of illicit substances and prevalence of substance use disorders experienced by Australian women. Mothers' use of illicit drugs was generally restricted to cannabis. By contrast the majority of daughters report lifetime use of an illicit drug with cannabis, club drugs and stimulants the most common. Compared to the mothers, daughters used club drugs 50 times, cocaine 19 times and inhalants 20 times more often. Daughters report experiencing 12 times the rate of cocaine use disorders, 9 times the rate of stimulant disorders and 7 times the rate of cannabis use disorders compared to their mothers.

CONCLUSIONS

Mothers of the current generation of 30 year old Australian women rarely used illicit drugs and few experienced a drug use disorder. The current generation of young women report commonly using one or more illicit drugs with a substantial minority experiencing a drug use disorder. It is unlikely that the use of illicit drugs by young women in Australia will be reversed in the foreseeable future. Government policies and treatment practices need to be calibrated to the reality of the much greater contact with illicit drugs being exhibited by younger women.

The growing transition from lifetime marijuana use to frequent use among 12th grade students: U.S. National data from 1976 to 2019

BACKGROUND

More United States adolescents now report high-frequency marijuana use than similar use levels of alcohol or tobacco. Increased high-frequency use raises questions such as (a) is frequent use likelihood growing among adolescents who experiment with use? (b) Is such change observed equally across sex and racial/ethnic subgroups? (c) Have sociodemographic and other covariate associations with frequent use changed over time?

METHODS

Data were obtained from 649,505 12th grade students participating in the cross-sectional, nationally-representative Monitoring the Future study from 1976 to 2019. Historical trends were modeled for any and frequent (20+ occasions) past 30-day marijuana use among all students and lifetime users, and lifetime user sex and racial/ethnic subgroups. Multivariable logistic regression estimates from 1989 to 1993 (lowest prevalence years) versus 2015-2019 (most recent years) were compared to examine covariate association changes with frequent use.

RESULTS

Among all students, recent linear trends in any and frequent marijuana use were not significantly different from zero (0.023 [SE 0.156] and 0.036 [0.073], respectively); frequent use among lifetime users increased (0.233 [0.107], p = 0.048). Among lifetime users, the increase was stronger for male than female students, and for minority versus White students. Significant association changes with race/ethnicity, parental education, and perceived risk were observed.

CONCLUSIONS

The proportion of adolescent lifetime marijuana users reporting current frequent marijuana use increased, and is now at near-record levels. Increases were particularly strong among males and minority students. There appears to be an increasing likelihood that adolescents who experiment with marijuana use may progress to frequent use.

Why now? Examining antecedents for substance use initiation among African American adolescents

Current adolescent substance use risk models have inadequately predicted use for African Americans, offering limited knowledge about differential predictability as a function of developmental period. Among a sample of 500 African American youth (ages 11-21), four risk indices (i.e., social risk, attitudinal risk, intrapersonal risk, and racial discrimination risk) were examined in the prediction of alcohol, marijuana, and cigarette initiation during early (ages 11-13), mid (ages 16-18), and late (ages 19-21) adolescence. Results showed that when developmental periods were combined, racial discrimination was the only index that predicted initiation for all three substances. However, when risk models were stratified based on developmental period, variation was found within and across substance types. Results highlight the importance of racial discrimination in understanding substance use initiation among African American youth and the need for tailored interventions based on developmental stage.

A growing need for youth mental health services in Canada: examining trends in youth mental health from 2011 to 2018

AIMS

The mental health of youth is continually changing and requires reliable monitoring to ensure that adequate social and economic resources are allocated. This study assessed trends in mental health among Canadian youth, 12-24 years old. Specifically, we examined the prevalence of poor/fair perceived mental health, diagnosis of mood and anxiety disorders, suicidality, perceived stress and sleep problems, substance use, and mental health consultations.

METHODS

Data were collected from eight cycles of the annual Canadian Community Health Survey (2011-2018). Prevalence of mental health outcomes was calculated from each survey, and meta-regression was used to assess trends over time. In the absence of a significant trend over time, the eight cycles were pooled together using meta-analysis techniques to gain precision. Trends in prevalence were assessed for the overall sample of youth (12-24 years) and separately for male and female adolescents (12-18 years) and young adults (19-24 years).

RESULTS

The prevalence of poor/fair perceived mental health, diagnosed mood and anxiety disorders, and past-year mental health consultations increased from 2011 to 2018, most strongly among young adult females. Past-year suicidality increased among young adult females but did not change for other age and sex groups. Notably, the prevalence of binge drinking decreased by 2.4% per year for young adult males, 1.0% for young adult females and 0.7% per year for adolescent males, while staying relatively stable for adolescent females. Prevalence of cannabis use declined among adolescents before legalisation (2011-2017); however, this trend did not persist in 2018. Instead, the 2018 prevalence was 5.6% higher than the 2017 prevalence (16.3 v. 10.7%). The combined prevalence of other illicit drug use was stable at 4.6%; however, cocaine use and hallucinogens increased by approximately 0.2% per year.

CONCLUSIONS

Our findings highlight a growing need for youth mental health services, as indicated by a rise in the prevalence of diagnosed mood and anxiety disorders and past-year mental health consultations. The reason for these observed increases is less apparent - it may represent a true rise in the prevalence of mental illness, or be an artefact of change in diagnostic practices, mental health literacy or diminishing stigma. Nonetheless, the findings indicate a need for the health care system to respond to the rising demand for mental health services among youth.

Modes of Marijuana Consumption Among Colorado High School Students Before and After the Initiation of Retail Marijuana Sales for Adults

OBJECTIVE

This study aimed to estimate the prevalence of different modes of marijuana consumption (e.g., smoking, ingesting) overall and by sociodemographic factors, marijuana-related perceptions, and other substance use among adolescents, as well as to characterize differences in the usual mode of consumption before and after the initiation of retail marijuana sales in 2014.

METHOD

Data are from the 2013 and 2015 administrations of the Healthy Kids Colorado Survey, a cross-sectional, school-based survey. We included 9th-12th grade students who reported past-30-day marijuana use in 2013 (n = 2,792; 44.8% female) or 2015 (n = 1,664; 48.9% female). We estimated the prevalence of any past-month use of each mode in 2015 and usual mode of consumption the past month in both years. We tested differences by year, sociodemographics, marijuana-related perceptions, and other substance use using Rao-Scott chi-square tests and multivariable logistic regression.

RESULTS

The prevalence of past-month marijuana use was 20.7% in both years. In 2015, 39.8% of students reported using multiple modes in the past month. Use of any mode other than smoking and use of multiple modes differed by sociodemographics, marijuana-related perceptions, and other substance use. Smoking remained the most common usual mode in 2015. The prevalence of usually ingesting significantly decreased from 4.7% to 2.1% between years, whereas "other mode(s)" significantly increased from 4.0% to 6.0%.

CONCLUSIONS

The use of multiple modes of marijuana consumption was prevalent among adolescents in Colorado. The usual mode of consumption changed in years before and after the implementation of retail marijuana sales, suggesting the need for continued surveillance.

Race/Ethnicity Differences in Trends of Marijuana, Cigarette, and Alcohol Use Among 8th, 10th, and 12th Graders in Washington State, 2004-2016

Accurate estimates of substance use in the teenage years by race/ethnicity may help identify when to intervene to prevent long-term substance use disparities. We examined trends in past 30-day use of marijuana, cigarette, and alcohol among 8th, 10th, and 12th graders in Washington State, which passed a recreational marijuana law in 2012 and initiated retail marijuana sales in 2014. Data are from the 2004-2016 Washington Healthy Youth Surveys (n = 161,992). We used time series regression models to assess linear and quadratic trends in substance use for the full sample and stratified on race/ethnicity and grade level and examined relative differences in prevalence of use by race/ethnicity. In Washington, across all racial/ethnic groups, marijuana use peaked in 2012. Although there was not a significant overall change in marijuana use for the full sample across the study period, there was a statistically significant increase in use among 12th graders and a statistically significant decrease among 8th graders. Relative to Whites, Asians had a lower prevalence of marijuana use, whereas all other race/ethnicity groups had a higher prevalence of use. Prevalence of marijuana use is particularly high among American Indian/Alaska Native and Black youth and has increased most rapidly among 12th grade Hispanic/Latinx youth. There were large and statistically significant decreases in alcohol and cigarette use across the study period for the full sample, as well as for each race/ethnicity group. These findings highlight the need for continued monitoring of trends in use among these groups and potentially warrant consideration of selective interventions that specifically focus on students of color and that include developmentally-appropriate strategies relevant to each grade.

Extension of the Theory of Planned Behavior (TPB) to Predict Patterns of Marijuana Use among Young Iranian Adults

Background: Marijuana use is increasing among adolescents and young adults. Long-term marijuana use magnifies the risk of a wide variety of behavioral, cognitive-emotional, and neurological problems, and can be a gateway to use of other drugs. In the present study, we investigated the cognitive-emotional and behavioral predictors of marijuana use. To this end, young Iranian adults answered questions based on an extended Theory of Planned Behavior (TPB) and related it to marijuana use. We hypothesized that cognitive-emotional and behavioral factors would predict intention to use marijuana, and that this, in turn, would predict actual consumption. Methods: A total of 166 young Iranian adults (mean age: 20.51 years; 15.7% females) attending a walk-in center for drug use took part in this cross-sectional study. Participants completed questionnaires covering sociodemographic information, frequency of marijuana use per week, along with questionnaires assessing the following dimensions of the TPB: attitude towards marijuana use, subjective norms, self-efficacy to resist marijuana use, environmental constraints, problem-solving skills, and behavioral intention for marijuana use. Results: Mean marijuana use was found to be 4.6 times/week. Attitude towards marijuana use, subjective norms, environmental constraints, and behavioral intention to use marijuana were positively correlated to each other and with marijuana use/week. In contrast, higher self-efficacy and problem-solving skills were associated with lower marijuana use/week. The multiple regression analysis showed that a positive attitude to marijuana use, lower self-efficacy in resisting its use, higher behavioral intention, and poorer problem-solving skills predicted actual use. Conclusion: The pattern of results suggests that dimensions of TPB can explain marijuana use among young Iranian adults self-admitted to a walk-in center for drug use. Specifically, poor problem-solving skills, low self-efficacy in resisting marijuana use, and positive labelling of its use appeared to be the best predictors of actual use. It follows that prevention programs aimed at improving problem-solving skills and raising self-efficacy, along with educational interventions aimed at highlighting the negative effects of marijuana might decrease the risk of its use among young adults in Iran.

Gender Norms, Roles and Relations and Cannabis-Use Patterns: A Scoping Review

Currently, boys and men use cannabis at higher rates than girls and women, but the gender gap is narrowing. With the legalization of recreational cannabis use in Canada and in multiple US states, these trends call for urgent attention to the need to consider how gender norms, roles and relations influence patterns of cannabis use to inform health promotion and prevention responses. Based on a scoping review on sex, gender and cannabis use, this article consolidates existing evidence from the academic literature on how gender norms, roles and relations impact cannabis-use patterns. Evidence is reviewed on: adherence to dominant masculine and feminine norms and cannabis-use patterns among adolescents and young adults, and how prevailing norms can be both reinstated or reimagined through cannabis use; gendered social dynamics in cannabis-use settings; and the impact of gender roles and relations on cannabis use among young adults of diverse sexual orientations and gender identities. Findings from the review are compared and contrasted with evidence on gender norms, roles and relations in the context of alcohol and tobacco use. Recommendations for integrating gender transformative principles in health promotion and prevention responses to cannabis use are provided.

Protective factors against juvenile delinquency: Exploring gender with a nationally representative sample of youth

Youth's social bonds' with conventional social institutions (e.g., family and school) and parental management of youth's leisure time represent two dimensions of suppressants against juvenile delinquency. Using Multivariate regression, this paper assesses these two dimensions of factors simultaneously on youth's aggressive and non-aggressive delinquency, and examines if their effects are gender sensitive. Findings suggest that girls have significantly lower involvement in both aggressive and non-aggressive delinquency than boys. However, girls are disproportionately involved in non-aggressive delinquency. Parental monitoring protects boys and girls distinctively on aggressive delinquency; this factor has a more pronounced inhibitory effect on girls' aggressive behavior. This study elucidates that there is a gendered pattern in adolescent delinquency, and that gender moderates the effect of some protective factor.

Sex differences in the acute effects of smoked cannabis: evidence from a human laboratory study of young adults

RATIONALE

Animal studies have found robust sex differences in the pharmacokinetics and pharmacodynamics of Δ⁹-tetrahydrocannabinol (THC). However, the human evidence remains equivocal, despite findings that women may experience more severe consequences of cannabis use than men.

OBJECTIVES

The objective of this secondary analysis was to examine sex differences in THC pharmacokinetics and in acute subjective, physiological, and cognitive effects of smoked cannabis in a sample of regular cannabis users (use 1-4 days per week) aged 19-25 years.

METHODS

Ninety-one healthy young adults were randomized to receive active (12.5% THC; 17 females, 43 males) or placebo (< 0.1% THC; 9 females, 21 males) cannabis using a 2:1 allocation ratio. Blood samples to quantify concentrations of THC, 11-OH-THC, and 11-Nor-carboxy-THC (THC-COOH), as well as measures of subjective drug effects, vital signs, and cognition were collected over a period of 6 h following ad libitum smoking of a 750-mg cannabis cigarette.

RESULTS

Females smoked less of the cannabis cigarette than males (p = 0.008) and had a lower peak concentration of THC and THC-COOH than males (p ≤ 0.01). Blood THC concentrations remained lower in females even when adjusting for differences in estimated dose of THC inhaled. There was very little evidence of sex differences in visual analog scale (VAS) ratings of subjective drug effects, mood, heart rate, blood pressure, or cognitive effects of cannabis.

CONCLUSIONS

Females experienced the same acute effects of smoked cannabis as males at a lower observed dose, highlighting the need for more research on sex differences in the pharmacology of THC, especially when administered by routes in which titrating to the desired effect is more difficult (e.g., cannabis edibles).

Sex- and Gender-Based Analysis in Cannabis Treatment Outcomes: A Systematic Review

There is evidence that sex- and gender-related factors are involved in cannabis patterns of use, health effects and biological mechanisms. Women and men report different cannabis use disorder (CUD) symptoms, with women reporting worse withdrawal symptoms than men. The objective of this systematic review was to examine the effectiveness of cannabis pharmacological interventions for women and men and the uptake of sex- and gender-based analysis in the included studies. Two reviewers performed the full-paper screening, and data was extracted by one researcher. The search yielded 6098 unique records—of which, 68 were full-paper screened. Four articles met the eligibility criteria for inclusion. From the randomized clinical studies of pharmacological interventions, few studies report sex-disaggregated outcomes for women and men. Despite emergent evidence showing the influence of sex and gender factors in cannabis research, sex-disaggregated outcomes in pharmacological interventions is lacking. Sex- and gender-based analysis is incipient in the included articles. Future research should explore more comprehensive inclusion of sex- and gender-related aspects in pharmacological treatments for CUD.

Persisting Reductions in Cannabis, Opioid, and Stimulant Misuse After Naturalistic Psychedelic Use: An Online Survey

BACKGROUND

Observational data and preliminary studies suggest serotonin 2A agonist psychedelics may hold potential in treating a variety of substance use disorders (SUDs), including opioid use disorder (OUD).

AIMS

The study aim was to describe and analyze self-reported cases in which naturalistic psychedelic use was followed by cessation or reduction in other substance use.

METHODS

An anonymous online survey of individuals reporting cessation or reduction in cannabis, opioid, or stimulant use following psychedelic use in non-clinical settings.

RESULTS

Four hundred forty-four respondents, mostly in the USA (67%) completed the survey. Participants reported 4.5 years of problematic substance use on average before the psychedelic experience to which they attributed a reduction in drug consumption, with 79% meeting retrospective criteria for severe SUD. Most reported taking a moderate or high dose of LSD (43%) or psilocybin-containing mushrooms (29%), followed by significant reduction in drug consumption. Before the psychedelic experience 96% met SUD criteria, whereas only 27% met SUD criteria afterward. Participants rated their psychedelic experience as highly meaningful and insightful, with 28% endorsing psychedelic-associated changes in life priorities or values as facilitating reduced substance misuse. Greater psychedelic dose, insight, mystical-type effects, and personal meaning of experiences were associated with greater reduction in drug consumption.

CONCLUSIONS

While these cross-sectional and self-report methods cannot determine whether psychedelics caused changes in drug use, results suggest the potential that psychedelics cause reductions in problematic substance use, and support additional clinical research on psychedelic-assisted treatment for SUD.

Sex and Gender Interactions on the Use and Impact of Recreational Cannabis

Cannabis is the second most frequently used substance in the world and regulated or legalized for recreational use in Canada and fourteen US states and territories. As with all substances, a wide range of sex and gender related factors have an influence on how substances are consumed, their physical, mental and social impacts, and how men and women respond to treatment, health promotion, and policies. Given the widespread use of cannabis, and in the context of its increasing regulation, it is important to better understand the sex and gender related factors associated with recreational cannabis use in order to make more precise clinical, programming, and policy decisions. However, sex and gender related factors include a wide variety of processes, features and influences that are rarely fully considered in research. This article explores myriad features of both sex and gender as concepts, illustrates their impact on cannabis use, and focuses on the interactions of sex and gender that affect three main areas of public interest: the development of cannabis use dependence, the impact on various routes of administration (ROA), and the impact on impaired driving. We draw on two separate scoping reviews to examine available evidence in regard to these issues. These three examples are described and illustrate the need for more comprehensive and precise integration of sex and gender in substance use research, as well as serious consideration of the results of doing so, when addressing a major public health issue such as recreational cannabis use.

Predictors of Substance Use Latent Classes Among American Indian Youth Attending Schools On or Near Reservations

BACKGROUND AND OBJECTIVES

Identical latent classes of substance use for 7 to 8 grade and 9 to 12 grade American Indian (AI) youth living on or near reservations suggest that patterns of substance use are established early among these youth. This study examines relationships of substance-related factors to latent class membership and whether these relationships differ by grade group.

METHODS

In-school surveys were administered to 1503 7 to 8 grade and 1995 9 to 12 grade students from 46 schools on or near reservations during the 2009/2010 to 2012/2013 school years. Four-class latent class models of substance use were specified and five classes of substance-related factors (peers, substance availability, perceived harm, family, early initiation), plus grade level and gender, were evaluated as predictors.

RESULTS

For 7 to 8 grade students, substance-related factors differentiated nonusers from users, while for 9 to 12 graders, these factors also differentiated types of users. Early initiation and peer factors were strongly related to class membership, while other factors were less strongly related.

DISCUSSION AND CONCLUSIONS

Early initiation of alcohol or marijuana is strongly related to being in a substance-using class for AI youth. Because these youth tend to initiate use earlier that other US youth, prevention resources should be targeted to reaching them and their families before age 12.

SCIENTIFIC SIGNIFICANCE

Predictors of latent classes of substance use were identified for reservation-based AI youth. While the classes were identical for 7 to 8 grade and 9 to 12 grade youth, predictors varied across grade group, which may inform how best to develop prevention efforts unique to middle and high school AI youth.

A Trend Analysis of Age of First Marijuana Use Among High School Students in the United States From 1991 to 2017

Background. Marijuana is the most commonly used illicit drug in the United States. There has been a rapidly changing marijuana policy environment and increased acceptability related to marijuana in the United States. How the changing environment will potentially influence adolescents age of initiation remains unknown. While much of extant literature has primarily focused on current marijuana use, less is known about age of first use. This study examined trends in adolescents' age of first marijuana use in the United States. Method. Data were drawn from the 1991 to 2017 Youth Risk Behavior Survey. We used linear regression for age of first use as a continuous variable, and logistic regression for marijuana use before the age of 15 years as a dichotomous variable. Joinpoint regression analysis identified where significant changes in trend occurred. Results. Results showed that the mean age of first marijuana use increased significantly between 1991 and 2017. Males had a younger age of first use than females. Between 1991 and 1997, there was an increasing trend in the prevalence of marijuana use before the age of 15 years in all adolescents and in subgroups for males, females, all races, and 9th and 10th grades. After 1997, a significant downward trend was found in all adolescents. Conclusions. Our results do not indicate an overall decreasing trend of age of first use among the general adolescent population. Results show a downward trend in the use of marijuana before the age of 15 years since 1997.

Age, period and cohort effects in frequent cannabis use among US students: 1991-2018

BACKGROUND AND AIMS

As the legal status of cannabis changes across the United States and modes of administration expand, it is important to examine the potential impact on adolescent cannabis use. This study aimed to assess changes in prevalence of frequent cannabis use in adolescents in the United States and how far this varies by age and cohort.

DESIGN

Analysis of Monitoring the Future, a nationally representative annual survey of 8th-, 10th- and 12th-grade students in the United States conducted from 1991 to 2018.

SETTING

In-school surveys completed by US adolescents.

PARTICIPANTS

A total of 1 236 159 8th-, 10th- and 12th-graders; 51.5% female, 59.6% non-Hispanic white, 12.3% non-Hispanic black, 13.4% Hispanic and 14.7% other race/ethnicity.

MEASUREMENTS

Frequent cannabis use (FCU), defined as six or more occasions in the past 30 days, stratified by sex, race/ethnicity and parental education.

FINDINGS

FCU among US adolescents increased over the study period; the peak in 2010-18 was 11.4% among 18-year-old students. This increase was best explained by both period and cohort effects. Compared with respondents in 2005, adolescents surveyed in 2018 had period effects in FCU that were 1.6 times greater. Adolescents in younger birth cohorts (those born > 1988) had a lower increase in FCU than those born prior to 1988. Results were consistent across sex, parent education and race/ethnicity, with period effects indicating increasing FCU after 2005 and cohort effects indicating a lower magnitude of increase in more recent birth cohorts. Age and parental education disparities in FCU have increased over time, whereas race/ethnicity differences have converged over time; black students were 0.67 [95% confidence interval (CI) = 0.64-0.70] times as likely to use cannabis frequently as white students from 1991 to 2000, and 1.03 (95% CI = 0.98-1.09) times as likely from 2011 to 2018 (P-value for time interaction < 0.001).

CONCLUSIONS

The prevalence of frequent cannabis use (FCU) increased from 1991 to 2018 among older adolescents in the United States. Racial/ethnic differences in FCU converged, whereas parental education differences have diverged.

Age Differences in Daily and Nondaily Cannabis Use in the United States, 2002-2014

OBJECTIVE

Adult cannabis use has increased in the United States since 2002, particularly after 2007, contrasting with stable/declining trends among youth. We investigated whether specific age groups disproportionately contributed to changes in daily and nondaily cannabis use trends.

METHOD

Participants ages 12 and older (N = 722,653) from the 2002-2014 National Survey on Drug Use and Health reported past-year cannabis use frequency (i.e., daily = ≥300 days/year; nondaily = 1-299 days/year; none). Multinomial logistic regression was used to model change in past-year daily and nondaily cannabis use prevalence by age group (i.e., 12-17, 18-25, 26-34, 35-49, 50-64, ≥65), before and after 2007. Multinomial logistic regressions estimated change in relative odds of cannabis use frequency over time by age, adjusting for other sociodemographics.

RESULTS

Daily cannabis use prevalence decreased in ages 12-17 before 2007 and increased significantly across adult age categories only after 2007. Increases did not differ significantly across adult ages 18-64 and ranged between 1 and 2 percentage points. Nondaily cannabis use decreased among respondents ages 12-25 and 35-49 before 2007 and increased across adult age categories after 2007, particularly among adults 26-34 (i.e., 4.5 percentage points). Adjusted odds of daily versus nondaily cannabis use increased after 2007 for ages 12-64.

CONCLUSIONS

Increases in daily and nondaily cannabis use prevalence after 2007 were specific to adult age groups in the context of increasingly permissive cannabis legislation, attitudes, and lower risk perception. Although any cannabis use may be decreasing among teens, relative odds of more frequent use among users increased in ages 12-64 since 2007. Studies should assess not only any cannabis use, but also frequency of use, to target prevention efforts of adverse effects of cannabis that are especially likely among frequent users.

Examining prevalence and correlates of cigarette and marijuana co-use among young adults using ten years of NHANES data

BACKGROUND

Prior research has documented a strong association between cigarette and marijuana use among young adults; it is critical to study patterns and risk factors for co-use.

METHODS

Appended, cross-sectional National Health and Nutrition Examination Survey (NHANES) data were used to assess prevalence and correlates of cigarette and marijuana co-use among young adults (ages 21-30) over a 10-year period (2005-2014). Respondents (unweighted sample = 4,948) were classified into four categories regarding past-month behavior: neither use, cigarette-only use, marijuana-only use, and co-use of both. Regression models were computed to predict these categories using three waves of NHANES (unweighted sample = 3,073).

RESULTS

Prevalence of past-month cigarette use decreased from 30.9% in 2005-2006 to 23.7% in 2013-2014 (p = 0.024) while past-month marijuana use (average 18.0%) and past-month co-use (average 9.8%) remained stable during this time. Co-use differed significantly by gender (p < 0.001; average 12.9% men, 6.8% women). Co-users were less likely to be married, more likely to endorse non-Hispanic black racial identity, more likely to have engaged in non-marijuana drug use in their lifetime and more likely to drink alcohol monthly than cigarette-only users. Co-users were more likely to have depressive symptoms, ever use non-marijuana drugs, live with a smoker, and initiate marijuana at a younger age than marijuana-only users.

CONCLUSIONS

Co-use of cigarettes and marijuana remained stable but high over a ten-year period; understanding the unique characteristics, living situations, experiences, and substance use behaviors of co-users can contribute to more effective, tailored prevention and education strategies to reduce the burden of comorbid cigarette and marijuana use.

Cocaine use is declining among emerging adults in the United States: Trends by college enrollment

BACKGROUND

The difference in cocaine use between student and non-student emerging adults is not well understood, despite the longstanding assumption that college is protective against use.

OBJECTIVE

To describe trends in cocaine use among emerging adults by college enrollment.

METHODS

Using cross-sectional, nationally-representative data from the National Survey on Drug Use and Health (2002-2016), we estimated the prevalence of four cocaine use indicators by year among emerging adults (ages 18-22) and stratified by college enrollment. We tested for linear and quadratic trends over time.

RESULTS

From 2002 to 2016, 11.7% reported lifetime cocaine use, 5.8% reported past 12-month use, 1.7% reported past 30-day use, and 1% had a use disorder in the past 12-months. We observed significant linear decreases in all four use indicators over time (Lifetime: β = -0.20, Past 12-months: β = -0.17, Past 30-days: β = -0.22, Past 12-months disorder: β = -0.37). Students had lower rates of cocaine use than non-students, although prevalence estimates were more similar between groups for past 12-month (Students:5.3%, 95% CI:5.0-5.5; Non-students:6.3%, 95% CI:6.1-6.5) and past 30-day use (Students:1.6%, 95% CI:1.4-1.7; Non-students:1.8%, 95% CI:1.7-1.9) than for lifetime use (Students:9.4%, 95% CI:9.1-9.7; Non-students:13.8%, 95% CI:13.5-14.1).

CONCLUSIONS

Cocaine use has declined among emerging adults since the early 2000s. The college environment appears compensate for early life differences in cocaine use risk between students and non-students, closing the gap between groups for recent indicators of cocaine use. Given the severe health consequences associated with cocaine use, more public health attention to this issue is needed.

What Every Pediatric Gynecologist Should Know About Marijuana Use in Adolescents

Use of marijuana in adolescent girls is common and shows no sign of decreasing. With recent trends toward legalization of "recreational" and "medical" marijuana products, adolescents are increasingly faced with information and misinformation about the health effects of marijuana use. We review the current literature on the risks and potential benefits of marijuana use during adolescence with a specific focus on pediatric and adolescent gynecological conditions. Despite limited research on this topic, the many risks associated with marijuana use in adolescents, including negative effects on the developing brain and adverse reproductive, sexual health, and mental health outcomes, likely outweigh potential benefits in this population.

Employment and Marijuana Use Among Washington State Adolescents Before and After Legalization of Retail Marijuana

PURPOSE

The purpose of the study was to describe associations between employment and marijuana use among adolescents 2 years before passage of 2012 ballot initiative and 2 years after the implementation of retail recreational marijuana sales took place in Washington.

METHODS

We used 2010 and 2016 data from Washington's statewide school-based Healthy Youth Survey, which is completed by more than 76,000 youth annually and representative of 8th, 10th, and 12th graders in public schools. We used "difference-in-differences" regression to estimate the odds of current, past 30-day marijuana use by working status and hours worked per week compared with nonworking youth.

RESULTS

Working adolescents in all grades had higher prevalence of recent marijuana use compared with nonworking adolescents. Youth working in formal settings, such as retail and service sectors, were more likely to use marijuana than nonworking and youth working in informal settings, such as babysitting. Between 2010 and 2016, marijuana use decreased significantly among working and nonworking 8th and 10th graders. Among working 12th graders, marijuana use increased significantly over time relative to nonworking youth (adjusted odds ratio: 1.34, 95% confidence interval: 1.22-1.48). Associations were stronger for youth who worked more hours per week.

CONCLUSIONS

Working youth were more likely to use marijuana before and after Washington's legalization of retail marijuana. Legalization was associated with increases in marijuana use specifically among 12th-grade working youth. States legalizing marijuana may consider implementing interventions to support healthy behaviors among working youth.

Trends in binge drinking and alcohol abstention among adolescents in the US, 2002-2016

BACKGROUND

Binge drinking accounts for several adverse health, social, legal, and academic outcomes among adolescents. Understanding trends and correlates of binge drinking and alcohol abstention has important implications for policy and programs and was the aim of this study. The current study examined trends in adolescent binge drinking and alcohol abstention by age, gender, and race/ethnicity over a 15-year period.

METHODS

Respondents between the ages of 12 and 17 years who participated in the National Survey on Drug Use and Health (NSDUH) between 2002 and 2016 were included in the sample of 258,309. Measures included binge drinking, alcohol abstention, and co-morbid factors (e.g., marijuana, other illicit drugs), and demographic factors.

RESULTS

Logistic regression analyses were conducted to examine the significance of trend changes by sub-groups while controlling for co-morbid and demographic factors. Findings indicated that binge drinking decreased substantially among adolescents in the US over the last 15 years. This decrease was shown among all age, gender, and racial/ethnic groups. In 2002, Year 1 of the study, 26% of 17-year-olds reported past-month binge drinking; in 2016, past-month binge drinking dropped to 12%. Findings also indicated comparable increases in the proportion of youth reporting abstention from alcohol consumption across all subgroups. Black youth reported substantially lower levels of binge alcohol use and higher levels of abstention, although the gap between Black, Hispanic and White youth narrowed substantially between 2002 and 2016.

CONCLUSION

Study findings are consistent with those of other research showing declines in problem alcohol- use behavior among youth.

Increasing marijuana use for black adolescents in the United States: A test of competing explanations

AIMS

In the last decade the relatively lower levels of marijuana use for black relative to non-black high school seniors has grown smaller and disappeared, drawing to a close a unique disparity that actually favored a disadvantaged group for at least thirty years. In this study we test trends in cigarette smoking and religiosity as possible explanations for this closing disparity. The study also examines whether increasing marijuana levels for black adolescents is better characterized as a cohort effect or an historical period effect.

DESIGN

Analyses use relative risk regression and focus on data from yearly, cross-sectional surveys from the time period 2008-2017.

SETTING AND PARTICIPANTS

Data comes from the nationally-representative Monitoring the Future survey, which conducts in-school surveys of secondary school students. The analysis uses data from 114,552 high school seniors (in 12th grade), 123,594 in 10th grade, and 136,741 in 8th grade.

FINDINGS

Past 12-month marijuana prevalence significantly increased for black as compared to non-black adolescents from 2008 to 2017 in 12th grade, 10th grade, and 8th grade. The increase attenuated by more than half and was not statistically significant after adjusting for cigarette smoking. In contrast, the increase was little changed after adjusting adolescent levels of religiosity. The increase is better characterized as a cohort effect than a period effect.

CONCLUSIONS

These results support the increase in marijuana use for black relative to non-black adolescents as an unexpected consequence of the great decline in adolescent cigarette smoking, which has occurred slower for black adolescents.

Time trends in US cannabis use and cannabis use disorders overall and by sociodemographic subgroups: a narrative review and new findings

Background: Due to significant comorbidity and impairment associated with cannabis use and cannabis use disorder, understanding time trends in cannabis use and cannabis use disorder is an important public health priority.Objectives: To identify trends in cannabis use and cannabis use disorder overall, and by sociodemographic subgroup.Methods: Narrative review of published findings on trends in cannabis use and cannabis use disorders in data from repeated cross-sectional US general population surveys. In addition, in National Epidemiologic Survey on Alcohol and Related Conditions (NESARC; 2002-2002) and NESARC-III (2012-2013) data, logistic regression was used to examine whether trends differed between subgroups of adults.Results: The review showed that in adults, cannabis use increased over the past decade overall and within sociodemographic subgroups (gender, age, race/ethnicity, income, education, marital status, urbanicity, region, pregnancy status, disability status), with greater increases in men and disabled adults. Most sources also indicated significant increases in cannabis use disorders. New analysis showed significantly greater increases in adult cannabis use and cannabis use disorder in men (p ≤ .0001); young adults (p < .05); Blacks (vs. Whites, p < .01); low income groups (p < .001); never-married p ≤ .0001), and urban residents (p < .05). In adolescents, cannabis use generally decreased, although recent increases were observed in older and non-White adolescents.Conclusion: Cannabis use and cannabis use disorder are increasing in adults, with specific sociodemographic groups at higher risk, and may be increasing in some adolescent subgroups. Studies should determine mechanisms for differential trends to provide information to policymakers and enable informed decisions on cannabis legalization and service planning.

Does Marijuana Use at Ages 16-18 Predict Initiation of Daily Cigarette Smoking in Late Adolescence and Early Adulthood? A Propensity Score Analysis of Add Health Data

Given the declining trend in adolescent cigarette smoking and increase in general access to marijuana, it is important to examine whether marijuana use in adolescence is a risk factor for subsequent cigarette smoking in late adolescence and early adulthood. Preliminary evidence from a very small number of studies suggests that marijuana use during adolescence is associated with later smoking; however, to control confounding, previously published studies used regression adjustment, which is susceptible to extrapolation when the confounder distributions differ between adolescent marijuana users and non-users. The current study uses propensity score weighting, a causal inference method not previously used in this area of research, to weight participants based on their estimated probability of exposure given confounders (the propensity score) to balance observed confounders between marijuana users and non-users. The sample consists of participants of Add Health (a nationally representative dataset of youth followed into adulthood) who were 16-18, with no history of daily cigarette smoking at baseline (n = 2928 for female and 2731 for male sub-samples). We assessed the effect of adolescent marijuana use (exposure, ascertained at wave 1) on any daily cigarette smoking during the subsequent 13 years (outcome, ascertained at wave 4). Analyses suggest that for females (but not males) who used marijuana in adolescence, marijuana use increased the risk for subsequent daily smoking: OR = 1.71, 95% CI = (1.13, 2.59). We recommend that adolescent marijuana use be viewed as a possible risk factor for subsequent initiation of daily cigarette smoking in women.

Adolescent Marijuana Use, Marijuana-Related Perceptions, and Use of Other Substances Before and After Initiation of Retail Marijuana Sales in Colorado (2013-2015)

Due to the recentness of changes to marijuana policies in a number of states, the effect on adolescent use and perceptions is not yet well understood. This study examines change in adolescent marijuana use and related perceptions in Colorado, before and after the implementation of legal commercial sale of recreational marijuana for adults starting on January 1, 2014. The data are from a repeated cross-sectional survey of a representative sample of Colorado high school students, with separately drawn samples surveyed in fall 2013 (prior to implementation) and fall 2015 (18 months after implementation). We examined change in the prevalence of adolescent marijuana use, measured by lifetime use, past 30-day use, frequent use, and use on school property. To consider the possibility of heterogeneity in the change in marijuana use, we examined change in past 30-day marijuana use by demographic characteristics (sex, grade, race/ethnicity), school characteristics (poverty, percent minority), urbanicity of the school district, and whether the city or county permitted retail marijuana stores. There was an absence of significant effects for change in lifetime or past 30-day marijuana use. Among those reporting past 30-day use, frequent use and use on school property declined. There was a significant decline in the perceived harm associated with marijuana use, but we did not find a significant effect for perceived wrongfulness, perceived ease of access, or perceived parental disapproval. We did not find significant variability in past 30-day use by demographic characteristics or by school and community factors from 2013 to 2015. We did not find a significant effect associated with the introduction of legal sales of recreational marijuana to adults in Colorado on adolescent (illegal) use, but ongoing monitoring is warranted, including consideration of heterogeneity in the effects of marijuana policies.

When Marijuana Is Used before Cigarettes or Alcohol: Demographic Predictors and Associations with Heavy Use, Cannabis Use Disorder, and Other Drug-related Outcomes

Recent loosening of state and federal policy restrictions on marijuana, along with changes in social norms regarding marijuana use and decreases in prevalence of other types of substance use, may lead to increases in youth initiating marijuana before other types of substances such as alcohol and tobacco. We investigated predictors and potential consequences of initiating marijuana before other drugs for youth aged 12-21-years in the USA. Nationally representative, cross-sectional survey data from the US National Survey on Drug Use and Health supplied self-reported age of first marijuana, cigarettes, alcohol, other tobacco, and other illegal drug use among 12-21-year-old samples from 2004 to 2014 (n = 275,559). We first examined the degree to which initiating marijuana use first was associated with sex, age, race/ethnicity, and survey year. Then, we examined whether using marijuana first predicted heavy marijuana use, cannabis use disorder (CUD), alcohol use disorder (AUD), nicotine dependence (ND), or lifetime use of other illegal drugs. Among all survey youth (substance users and non-users), the proportion using marijuana first increased from 4.8 to 8.8% from 2004 to 2014. Those using marijuana first (vs. alcohol or cigarettes first) were more likely to be male and older and Black, American Indian/Alaskan Native, multiracial, or Hispanic than White or Asian. Among substance users and adjusting for age of onset and the number of substances used, using marijuana first was associated higher odds of heavy current marijuana use and CUD. In recent years, youth have been increasingly likely to use marijuana as their first drug and sequence of initiation is associated with race/ethnicity, gender, and age. Using marijuana first might increase the chance of heavy use and CUD.

Preliminary development of a neuroimaging paradigm to examine neural correlates of relationship conflict

Social stress in the form of conflict between romantic partners is a salient correlate of substance use disorders (SUD), and also plays an integral role in SUD treatment outcomes. Neuroimaging has advanced the study of social stress on SUD etiology, course, and treatment. However, no neuroimaging paradigms have yet been developed to examine neural responses to conflict among romantic couples. In order to fill this gap in the literature, the goal of this exploratory study was to examine the preliminary feasibility of a novel relationship conflict fMRI paradigm. We compared the effects of an auditory relationship conflict versus a neutral cue on functional connectivity in corticolimbic brain regions, and the associations between neural activities and self-report ratings of relationship adjustment, substance use problems, and intimate partner violence. We also explored sex differences in neural correlates of relationship conflict versus neutral cues. Participants demonstrated increased functional connectivity between the amygdala and the prefrontal cortex during the relationship conflict cue compared to the neutral cue. Intimate partner violence was associated with functional connectivity. Sex differences emerged in neural responses to the relationship conflict cue compared to the neutral cue. Collectively, the findings demonstrate preliminary validity of this novel neuroimaging paradigm for couples.

Peer Victimization, Mood Symptoms, and Alcohol Use: Examining Effects among Diverse High School Youth

Peer victimization is associated with alcohol use among adolescents. However, few studies have examined the mediating role of depression and anxiety, or differences by race. The current study examined the prospective relationship of peer victimization, depressive and anxiety symptoms, and alcohol use across two timeframes: 9th to 11th grade and 10th to 12th grade among African American and White youth. Two thousand two hundred and two high school youth (57.6% female) who identified as either African American (n = 342, 15.2%) or White (n = 1860, 82.6%) provided data on study variables. Path analysis among the overall sample indicated that anxiety symptoms was a significant mediator for both timeframes, with depressive symptoms mediating the pathway during the 10th to 12th grade timeframe. The findings were most consistent among White youth, with no significant indirect effects observed for African American youth. Thus, addressing depressive and anxiety symptoms may be effective targets to decrease alcohol use risk as a result of peer victimization among White youth. However, further research is needed to better understand risk models for peer victimization exposure on substance use outcomes among racial/ethnic minority youth.

Past-month cannabis use among U.S. individuals from 2002-2015: An age-period-cohort analysis

BACKGROUND

Cannabis is the most commonly used illicit drug among U.S. adolescents and adults, but little is known about factors that drive trends in cannabis use prevalence. To better understand drivers of these trends, we aimed to estimate age, period, and cohort effects on past-month cannabis use among U.S. individuals age 12 and older from 2002 to 2015.

METHODS

We conducted an age-period-cohort analysis on past-month cannabis use among participants ages 12 and older using the National Survey on Drug Use and Health (NSDUH), an annual cross-sectional nationally-representative survey of drug use. Additionally, we examined how age, period, and cohort effects differed across gender. Participants (n = 779,799) self-reported cannabis patterns using a computer-assisted telephone interview (CATI).

RESULTS

Past-month cannabis use in this population increased from 6.0% in 2002 to 8.1% in 2015. Distinct age, period, and cohort effects were observed. Compared to participants ages 12-13, participants ages 18-21 (PR: 16.8, 95% CI: 15.6, 18.1) and 22-25 (PR: 13.2, 95% CI: 12.2, 14.4) had dramatically higher prevalence of past-month cannabis use. Compared to participants in 2002, participants in 2014 (PR: 1.2, 95% CI: 1.1, 1.4) and 2014 (PR: 1.2, 95% CI: 1.1, 1.4) had slightly higher prevalence of past-month cannabis use. Compared to the 1940s birth cohort, the 1950s birth cohort (PR: 1.8, 95% CI: 1.5, 2.2) had a higher prevalence of past-month cannabis use.

CONCLUSIONS

Past-month cannabis use is prevalent and increasing among U.S. adults. Distinct age, period, and cohort effects are at play, though age effects are strongest.

Cannabis Use: Neurobiological, Behavioral, and Sex/Gender Considerations

PURPOSE OF REVIEW

To summarize the current literature on the effects of cannabinoids in humans and to discuss the existing literature on the sex- and gender-related differences in the effects of cannabinoids.

RECENT FINDINGS

Cannabis and its constituent cannabinoids are associated with risk of addiction, cognitive deficits and mood/psychotic disorders. Preclinical and emerging clinical data suggest greater sensitivity to the effects of cannabinoids in women.

SUMMARY

Cannabis is one of the most commonly used drugs with increasing rates of use. Women in particular may be at a greater risk of adverse outcomes given the previously described "telescoping effect" of substance use in women. Human data examining the sex- and gender-related differences in the effects of cannabinoids and factors underlying these differences are very limited. This represents a critical gap in the literature and needs to be systematically examined in future studies.

Perceived Discrimination and Substance Use among Adolescents: Examining the Moderating Effect of Distress Tolerance and Negative Urgency

BACKGROUND

Perceived discrimination has been found to increase substance use vulnerability among adolescent populations. However, less is known about individual level factors which may moderate this risk.

OBJECTIVES

The aim of the current study is to examine whether two emotion-based personality traits (i.e., distress tolerance and negative urgency) moderates the effect of perceived discrimination on substance use. We hypothesized that high distress tolerance would decrease risk, while high negative urgency would increase risk for substance use as a consequence of discrimination.

METHODS

108 youth ages 12-18 (68.6% male; 56.2% African-American) provided data on perceived discrimination, distress tolerance, negative urgency, and substance use (i.e., alcohol and marijuana use).

RESULTS

Contrary to our hypothesis, no moderating effect was observed for negative urgency. Distress tolerance was found to moderate the relationship, but in the opposite direction than expected.

CONCLUSIONS

It is speculated that this counterintuitive finding may be due to the racial/ethnic composition of the sample, suggesting that distress tolerance may operate differently among minority youth. Further research examining these relationships among minority youth is warranted.

Racial Differences in Mechanisms Linking Childhood Socioeconomic Status With Growth in Adult Body Mass Index: The Role of Adolescent Risk and Educational Attainment

PURPOSE

The present study examined whether risk factors during adolescence, including substance use, depression, overweight status, and young adult educational attainment, mediated the association between low childhood socioeconomic status (SES) and higher body mass index (BMI) in adulthood. We also evaluated whether the hypothesized pathways differed based on racial group status.

METHODS

Participants from the Seattle Social Development Project were followed from ages 10 to 39years. Thepresent study included white (n = 381), African American (n = 207), and Asian American (n = 171) participants. Structural equation models tested pathways linking low childhood SES to BMI from ages 24 to 39 years. Multiple-group modeling was used to test potential racial differences.

RESULTS

Analyses indicated racial differences in the pathways linking low childhood SES with adult BMI. For whites, overweight status and educational attainment were significant mediators. For Asian Americans, there was an unmediated and significant pathway between low childhood SES and low adult BMI. For African Americans, there were no significant mediated or unmediated pathways.

CONCLUSIONS

Results stress that the pathways that link childhood SES with adult BMI may operate differently based on race. Research is particularly needed to identify mechanisms for African Americans in order to better inform obesity prevention efforts.