‘High’-School: The Relationship between Early Marijuana Use and Educational Outcomes

We use unique survey data linked to nearly a decade of administrative income support data to examine the relationship between early marijuana use (at age 14 or younger) and young people's educational outcomes. We find evidence that early marijuana use is related to educational penalties that are compounded by high-intensity use and are larger for young people living in families with a history of income support receipt. The relationships between marijuana use and both high school completion and achieving a university entrance score appear to stem from selectivity into the use of marijuana. In contrast, early marijuana use is associated with significantly lower university entrance scores for those who obtain one, and we provide evidence that this effect is unlikely to be driven by selection. Collectively, these findings point to a more nuanced view of the relationship between adolescent marijuana use and educational outcomes than is suggested by the existing literature.

The Association between Tobacco Control Policies and Marijuana Use among Ontario Undergraduate Students

Background: Research indicates a steady increase in marijuana use and that it is concurrent with tobacco. There is speculation this concurrency reaches beyond use, to where policies aimed at reducing one may result in the reduction of the other. Purpose: To investigate the association between tobacco control policies and marijuana use among young adult undergraduates. Methods: A stratified sample of Ontario universities resulted in a sample of 4,966 participants. Results: Campuses with a moderately strong policy was found to be significantly associated with decreased marijuana use compared to campuses with a weak tobacco control policy. (OR=0.52, 95% CI: 0.36-0.76). Conclusions: The findings show tobacco control strategies are related to decreased odds of marijuana use among Ontario undergraduates. These findings are important to both policy makers and researchers interested in health strategies pertaining to marijuana and tobacco use and/or how health policies aimed at reducing one risk behaviour can affect another.

Developmental trajectories of marijuana use and psychological distress : exploring the co-occurrence of these phenomena in early adolescence

Le début de l’adolescence est une période de changements rapides où la détresse psychologique et l’expérimentation de la marijuana sont choses fréquentes. Certaines études longitudinales ont démontré que ces deux phénomènes ont tendance à se manifester conjointement tandis que d’autres n’ont pu observer de tel lien. Ces résultats divergents suggèrent que plusieurs questions persistent concernant la nature de cette relation. Cette thèse a pour objectif d’explorer la consommation de marijuana et la détresse psychologique en début d’adolescence afin de mieux saisir les changements à travers le temps, ainsi que d’examiner si ces deux problématiques évoluent conjointement et s’influencent réciproquement. Un échantillon de 448 adolescents garçons et filles fréquentant deux écoles secondaires de Montréal, ont été suivi de secondaire I à secondaire III. De 1999 à 2001, les participants ont complété un questionnaire à chaque année de l’étude incluant des mesures portant sur la consommation de marijuana et la détresse psychologique (IDPESQ-14). Un modèle de mixture semi-paramétrique (Nagin, 2005) a été utilisé afin d’identifier les trajectoires développementales de la consommation de marijuana et de détresse psychologique. Des analyses ont également été effectuées afin d’établir les liens d’appartenance entre chacune des trajectoires de consommation identifiées et la détresse psychologique lors de la première année de l`étude, ainsi qu’entre chacune des trajectoires de détresse psychologique et la consommation de marijuana en première année du secondaire. Finalement, des analyses de trajectoires jointes ont été effectuées afin de déterminer l’interrelation entre la consommation de marijuana et la détresse psychologique. Les résultats de notre étude suggèrent qu’il existe une grande hétérogénéité au niveau de la consommation de marijuana et la détresse psychologique. Trois trajectoires développementales ont été identifiées pour la consommation de marijuana: consommation légère, consommation grandissante et consommation élevée et stable. Trois trajectoires ont également été observées pour la détresse psychologique : basse, moyenne et élevée. Nos résultats démontrent la présence d’un lien entre la détresse psychologique rapportée lors de la première année de l’étude et les trajectoires de consommation problématiques. Ce lien a également été observé entre la consommation de marijuana rapportée lors de première année de l’étude et les trajectoires problématiques de détresse psychologique. Les analyses de trajectoires jointes démontrent la présence d’une concordance entre la consommation de marijuana et la détresse psychologique. Cette interrelation est toutefois complexe puisque les trajectoires de détresse psychologique élevée sont associées à un niveau de consommation de marijuana plus problématique mais l’inverse de cette association est moins probable. Notre étude met en lumière la nature asymétrique de la concordance entre la consommation de marijuana et la détresse psychologique.

Commitment language as a predictor of alcohol and marijuana use outcomes among adolescents in school -based group treatment

Despite widespread recognition of the problem of adolescent alcohol and other drug (AOD) abuse, research on its most common treatment modality, group work, is lacking. This research gap is alarming given that outcomes range from positive to potentially iatrogenic. This study sought to identify change mechanisms and/or treatment factors that are observable within group treatment sessions and that may predict AOD use outcomes. This NIH (F31 DA 020233-01A1) study evaluated 108, 10-19 year olds and the 19 school-based treatment groups to which they were previously assigned (R01 AA10246; PI: Wagner). Associations between motivational interviewing (MI) based change talk variables, group leader MI skills, and alcohol and marijuana use outcomes up to 12-months following treatment were evaluated. Treatment session audio recordings and transcripts (1R21AA015679-01; PI: Macgowan) were coded using a new discourse analysis coding scheme for measuring group member change talk (Amrhein, 2003). Therapist MI skills were similarly measured using the Motivational Interviewing Treatment Integrity instrument. Group member responses to commitment predicted group marijuana use at the 1-month follow up. Also, group leader empathy was significantly associated with group commitment for marijuana use at the middle and ending stages of treatment. Both of the above process measures were applied in a group setting for the first time. Building upon MI and social learning theory principles, group commitment and group member responses to commitment are new observable, in-session, process constructs that may predict positive and negative adolescent group treatment outcomes. These constructs, as well as the discourse analysis method and instruments used to measure them, raise many possibilities for future group work process research and practice.

The Impact of Marijuana Use on Memory in Patients with HIV/AIDS

The most robust neurocognitive effect of marijuana use is memory impairment. Memory deficits are also high among persons living with HIV/AIDS, and marijuana use among this population is disproportionately common. Yet research examining neurocognitive outcomes resulting from co-occurring marijuana and HIV is virtually non-existent. The primary aim of this case-controlled study was to identify patterns of neurocognitive impairment among HIV patients who used marijuana compared to HIV patients who did not use drugs by comparing the groups on domain T-scores. Participants included 32 current marijuana users and 37 non-drug users. A comprehensive battery assessed substance use and neurocognitive functioning. Among the full sample, marijuana users performed significantly worse on verbal memory tasks compared to non-drug users and significantly better on attention/working memory tasks. A secondary aim of this study was to test whether the effect of marijuana use on memory was moderated by HIV disease progression, but these models were not significant. This study also examined whether the effect of marijuana use was differentially affected by marijuana use characteristics, finding that earlier age of initiation was associated with worse memory performance. These findings have important clinical implications, particularly given increased legalization of this drug to manage HIV infection.

Assessing teen risk behavior and later drug use

Gemstone Team Risky Business

Perceived cannabis use norms and cannabis use among adolescents in the United States.

Due to changes in cannabis policies, concerns about cannabis use (CU) in adolescents have increased. The population of nonwhite groups is growing quickly in the United States. We examined perceived CU norms and their association with CU and CU disorder (CUD) for White, Black, Hispanic, Native-American, Asian-American, Native Hawaiian/Pacific Islander (NH/PI), and mixed-race adolescents. Data were from adolescents (12-17 years) in the 2004-2012 National Surveys on Drug Use and Health (N = 163,837). Substance use and CUD were assessed by computer-assisted, self-interviewing methods. Blacks, Hispanics, Native-Americans, and mixed-race adolescents had greater odds of past-year CU and CUD than Whites. Among past-year cannabis users (CUs), Hispanics and Native-Americans had greater odds of having a CUD than Whites. Asian-Americans had the highest prevalence of perceived parental or close friends' CU disapproval. Native-Americans and mixed-race adolescents had lower odds than Whites of perceiving CU disapproval from parents or close friends. In adjusted analyses, adolescent's disapproval of CU, as well as perceived disapproval by parents or close friends, were associated with a decreased odds of CU in each racial/ethnic group, except for NHs/PIs. Adolescent's disapproval of CU was associated with a decreased odds of CUD among CUs for Whites (personal, parental, and close friends' disapproval), Hispanics (personal, parental, and close friends' disapproval), and mixed-race adolescents (personal, close friends' disapproval). Racial/ethnic differences in adolescent CU prevalence were somewhat consistent with adolescents' reports of CU norm patterns. Longitudinal research on CU health effects should oversample nonwhite adolescents to assure an adequate sample for analysis and reporting.

Moderating effects of gender and general self-efficacy on the relationship between sensation-seeking and adolescent substance use /

This study performed a aecondvy dau analysis of information collected during the Youth Leisure Study (YLS). The purpose of this study was to examine the potential moderating influences of gender and general self-efTicacy on the relationships aoKXig sensation-seeking and various forms of substance use in adolescents. Specifically, the predictive ability of sensation seeking on five adolescents substance use outcomes (alcohol, tobacco, and marijuana use; binge drinking; and number of times drunk) was examined. Moderated hierarchical multiple regression (MHMR) analyses were used to examine the relationships among study variables. The results for this study indicate that the relationships among sensation-seeking and forms of adolescent substance use are more complex than literature suggests. Main effect relationships were found consistently for sensation-seeking and general self-efficacy with each of the outcome variables. Results for gender were not consistent across the substance use outcomes. Gender was a significant predictor for marijuana use only. The moderating effects of general self-efficacy (GSE) on the sensation-seekingsubstance use relationship were inconsistent. While no significant interactions were found for tobacco or alcohol use outcomes, GSE was found to moderate the relationship between sensation-seeking and marijuana use indicating that feelings of high general selfefficacy act as a buffer or guard against marijuana use. A consistent pattern was found among the alcohol use variables (alcohol use. binge drinking, and number of times drunk). Gender was found to moderate each of these variables indicating that higher levels of sensation seeking are more predictive of higher levels of adolescent alcohol use in males only. Implications of this study on the field of education, are discussed further, and suggestions for future research are presented.

Moderating effects of gender on the relationships among substance use and school outcomes /

The following study was a secondary analysis of data drawn from adolescents in South Western Ontario. The purpose of the study was to: examine the relationships among substance use and school outcomes, explore the relationships between gender and school outcomes, examine the moderating potential of gender on the substance useschool outcomes relationship, and to provide researchers and educators further knowledge of adolescent substance use behaviours. Many previous studies have failed to include the three most common substances used by adolescents (i.e., alcohol, tobacco, and marijuana). Furthermore, many studies have included only one school outcome instead of comparing several outcome variables. Moderated hierarchical regression was used to determine if gender moderated the substance use-school outcomes relationships. The dependent variables consisted of alcohol use, binge drinking, tobacco use, and marijuana use. Five measure of school outcomes were used as independent variables, including Grade Point Average, Positive School-role Behaviour, Negative School Behaviour, School Withdrawal, and School Misbehaviour. The results for this study indicated that substance use and gender were both predictors of all school outcome variables. Furthermore, gender was found to moderate 5 of the 25 substance use-school outcome relationships.

Relationships among adolescent substance use, leisure boredom, and physical activity

This study was a secondary analysis of data drawn from the Youth Leisure Study. The purpose of the study was to: a) explore the relationships among physical activity, leisure boredom, and various substance use variables; b) determine if leisure boredom moderated the relationship among physical activity and substance use variables; and c) create a foundation of knowledge with which to educate adolescents and educators of the importance of adopting and maintaining a healthy lifestyle early in life (i.e., free from unhealthy behaviours such as substance use and physical inactivity). Studies examining relationships among physical activity and substance are limited and, in the past, have yielded inconsistent results. The interaction of leisure boredom with physical activity intensity variables, including both team and individual pursuits were tested using moderated hierarchical regression procedures. Six measures of physical activity were used as independent variables, including, frequency of high, medium, and low intensity individual and team physical activities. Various types of substance use, including, tobacco, marijuana, and alcohol use, binge drinking, and drunkenness were used as dependent variables. The results for this study indicated that frequency of physical activity intensity was a consistent, positive predictor of alcohol use and binge drinking, but not tobacco use, marijuana use, or drunkenness. Leisure boredom was found to be a highly significant predictor of tobacco use, however, it was not a moderator of relationships among physical activity intensity and substance use variables. The implications for the study findings, are discussed further, and suggestions for future research are presented.

Does Education Setting Influence the Relationship between Substance use and Depression among Post Secondary Students

Background. This study examined whether experiences of and relationships between depressive symptoms and substance use differs for first year college and university students. Methods. A proportionate stratified random sample of 6,100 university students and a census sample of 7,300 college students were invited to anonymously complete the National College Health Assessment. The final sample included 444 young adult first year university (n = 298) and college (n = 146) students. Results. More college than university students used tobacco (26.7; 11.1%) and marijuana (26.7%; 20.8%). Similar proportions consumed alcohol (75.3%; 76.5%). Almost all students reported past-year depressive symptoms. Mean number of symptoms was 5.43. Tobacco, alcohol and marijuana use were each positively associated with depression after adjusting for age and gender. Educational setting moderated the relationship between depression and tobacco use, and depression and marijuana use, with the relationship being stronger for university students. Implications. University campus health professionals especially, need to assess depression among students using substances and vice versa. Differences between college and university students require further attention.

Whither RDS? An investigation of respondent driven sampling as a method of recruiting mainstream marijuana users.

Background: An important challenge in conducting social research of specific relevance to harm reduction programs is locating hidden populations of consumers of substances like cannabis who typically report few adverse or unwanted consequences of their use. Much of the deviant, pathologized perception of drug users is historically derived from, and empirically supported, by a research emphasis on gaining ready access to users in drug treatment or in prison populations with higher incidence of problems of dependence and misuse. Because they are less visible, responsible recreational users of illicit drugs have been more difficult to study. Methods: This article investigates Respondent Driven Sampling (RDS) as a method of recruiting experienced marijuana users representative of users in the general population. Based on sampling conducted in a multi-city study (Halifax, Montreal, Toronto, and Vancouver), and compared to samples gathered using other research methods, we assess the strengths and weaknesses of RDS recruitment as a means of gaining access to illicit substance users who experience few harmful consequences of their use. Demographic characteristics of the sample in Toronto are compared with those of users in a recent household survey and a pilot study of Toronto where the latter utilized nonrandom self-selection of respondents. Results: A modified approach to RDS was necessary to attain the target sample size in all four cities (i.e., 40 'users' from each site). The final sample in Toronto was largely similar, however, to marijuana users in a random household survey that was carried out in the same city. Whereas well-educated, married, whites and females in the survey were all somewhat overrepresented, the two samples, overall, were more alike than different with respect to economic status and employment. Furthermore, comparison with a self-selected sample suggests that (even modified) RDS recruitment is a cost-effective way of gathering respondents who are more representative of users in the general population than nonrandom methods of recruitment ordinarily produce. Conclusions: Research on marijuana use, and other forms of drug use hidden in the general population of adults, is important for informing and extending harm reduction beyond its current emphasis on 'at-risk' populations. Expanding harm reduction in a normalizing context, through innovative research on users often overlooked, further challenges assumptions about reducing harm through prohibition of drug use and urges consideration of alternative policies such as decriminalization and legal regulation.

Major Depressive Disorder, Suicidal Ideation, and Suicide Attempt in Twins Discordant for Cannabis Dependence and Early-Onset Cannabis Use

Background: Previous research has reported both a moderate degree of comorbidity between cannabis dependence and major depressive disorder (MDD) and that early-onset cannabis use is associated with increased risks for MDD. Objective: To examine whether associations between both lifetime cannabis dependence and early cannabis use and measures of MDD, suicidal ideation, and suicide attempt persist after controlling for genetic and/or shared environmental influences. Design: Cross-sectional survey of twin pairs discordant for lifetime cannabis dependence and those discordant for early cannabis use. Setting: General population sample of twins (median age, 30 years). Participants: Two hundred seventy-seven same-sex twin pairs discordant for cannabis dependence and 311 pairs discordant for early-onset cannabis use (before age 17 years). Main Outcome Measures: Self-report measures of DSM-IV-defined lifetime MDD, suicidal ideation, and suicide attempt. Results: Individuals who were cannabis dependent had odds of suicidal ideation and suicide attempt that were 2.5 to 2.9 times higher than those of their non-cannabis-dependent co-twin. Additionally, cannabis dependence was associated with elevated risks of MDD in dizygotic but not in monozygotic twins. Those who initiated cannabis use before age 17 years had elevated rates of subsequent suicide attempt (odds ratio, 3.5 [95% confidence interval, 1.4-8.6]) but not of MDD or suicidal ideation. Early MDD and suicidal ideation were significantly associated with subsequent risks of cannabis dependence in discordant dizygotic pairs but not in discordant monozygotic pairs. Conclusions: Comorbidity between cannabis dependence and MDD likely arises through shared genetic and environmental vulnerabilities predisposing to both outcomes. In contrast, associations between cannabis dependence and suicidal behaviors cannot be entirely explained by common predisposing genetic and/or shared environmental predispositions. Previously reported associations between early-onset cannabis use and subsequent MDD likely reflect shared genetic and environmental vulnerabilities, although it remains possible that early-onset cannabis use may predispose to suicide attempt.

The influence of neurocognitive impairment, alcohol and other drug (AOD) use, and psychosocial factors on antiretroviral treatment adherence, service utilization and viral load among HIV-seropositive adults

Among people living with HIV (PLWH), adherence to antiretroviral therapy (ART) can be affected by problems of neurocognitive (NC) impairment, stress, alcohol and other drug (AOD) abuse, and other barriers. The aims of this research were to: (1) examine factors associated with NC impairment, (2) explore relationships between psychosocial variables with ART adherence and viral load (VL), and (3) evaluate the efficacy of an evidence-based intervention in improving ART adherence, increasing service utilization, and decreasing VL. The first study (n=370) was cross sectional and used structural equation modeling to test whether AOD use, years living with HIV, and time from HIV diagnosis to seeking care were associated with poorer NC functioning. The second study (n=246) used similar methods to test the hypothesis that stress, barriers to adherence, NC impairment, poor social support, and AOD use were related to lower VL mediated by ART adherence. The third study (n=243) evaluated an evidence-based, eight-session program to improve ART adherence, reduce VL, and increase service utilization in a randomized controlled trial. Study participants were PLWH living in South Florida, 18 to 60 years old, with a history of alcohol abuse enrolled from January 2009 through November 2012. Secondary analysis of available data showed: (1) scores on interference with executive functioning increased by 0.32 for each day of marijuana use and 1.18 for each year living with HIV, but no association was found between alcohol use and NC functioning; (2) each barrier to adherence was associated with a 10% decrease in adherence to ART and a 0.42 unit increase in VL (log10) and the relationship between barriers and VL was partially mediated by ART adherence; (3) participants in the evidence-based program were more likely than the comparison group to report an undetectable VL (OR=2.25, p<0.01) at 6 months, but not 3 months, post-intervention. Psychosocial factors affect VL, but ART adherence is essential in achieving an undetectable VL in PLWH.