The adolescent cannabis check-up: randomized trial of a brief intervention for young cannabis users

The aim of this study was to evaluate the efficacy of a brief motivational enhancement therapy in reducing cannabis use and cannabis-related problems in a population of non-treatment-seeking adolescent cannabis users. In a randomized controlled trial, 40 young people (aged 14–19 years) were randomly assigned to either a two-session brief intervention or a 3-month delayed-treatment control condition. The intervention consisted of a detailed assessment and a session of motivational enhancement therapy. An additional optional discussion of skills for reducing or quitting cannabis use was offered if a participant was interested in discussing these issues. Primary outcome measures were changes in days of cannabis use, mean quantity of cannabis used weekly, and number of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition dependence symptoms reported. Significantly greater reductions on these measures were found in the Adolescent Cannabis Check-up group at 3-month follow-up. Between-group effect sizes were moderate. The approach is acceptable to participants and merits further evaluation with this difficult to reach population.     

Factors associated with the use of solvents and cannabis by medical students

INTRODUCTION: The use of alcohol and other drugs among medical students has been a theme of growing interest and concern on the part of researchers, teaching institutions and medical associations since the decade of the 1960's. OBJECTIVE: Recent use of alcohol, tobacco, tranquillisers, amphetamines, cannabis, organic solvents, and cocaine among 456 medical students was surveyed. METHOD: Assessment was done by means of a self-report questionnaire according to World Health Organisation guidelines. RESULTS: Among medical students, after alcohol and tobacco, cannabis and solvents are the most frequently used psychoactive substances. As such, they were the most deeply analysed drugs in this study. Factors associated with the recent use of cannabis and solvents were established by logistic regression. Living with parents or a companion appeared as a protective factor for the use of cannabis. However, being male and regularly participating in the activities at the campus Sports Association showed as risk factors for the use of both cannabis and solvents. DISCUSSION: Concepts and misconceptions concerning protective and risk factors must be discussed in the light of cultural and circumstantial interferences. Harm reduction strategies should be seriously considered.     

Associations between state-level policy liberalism,cannabis use,and cannabis use disorder from 2004 to 2012: Looking beyond medical cannabis law status

BackgroundMedical cannabis laws (MCL) have received increased attention as potential drivers of cannabis use (CU), but little work has explored how the broader policy climate, independent of MCL, may impact CU outcomes. We explored the association between state-level policy liberalism and past-year cannabis use (CU) and cannabis use disorder (CUD).MethodsWe obtained state-level prevalence of past-year CU and CUD among past year cannabis users for ages 12–17, 18–25, and 26+ from the 2004–2006 and 2010–2012 National Surveys on Drug Use and Health. States were categorized as liberal, moderate, or conservative based on state-level policy liberalism rankings in 2005 and 2011. Linear models with random state effects examined the association between policy liberalism and past-year CU and CUD, adjusting for state-level social and economic covariates and medical cannabis laws.ResultsIn adjusted models, liberal states had higher average past-year CU than conservative states for ages 12–17 (+1.58 percentage points; p = 0.03) and 18–25 (+2.96 percentage points; p = 0.01) but not for 26+ (p = 0.19). CUD prevalence among past year users was significantly lower in liberal compared to conservative states for ages 12–17 (−2.87 percentage points; p = 0.045) and marginally lower for ages 26+ (-2.45 percentage points; p = 0.05).ConclusionLiberal states had higher past-year CU, but lower CUD prevalence among users, compared to conservative states. Researchers and policy makers should consider how the broader policy environment, independent of MCL, may contribute to CU outcomes.     

The economic geography of medical cannabis dispensaries in California

BackgroundThe introduction of laws that permit the use of cannabis for medical purposes has led to the emergence of a medical cannabis industry in some US states. This study assessed the spatial distribution of medical cannabis dispensaries according to estimated cannabis demand, socioeconomic indicators, alcohol outlets and other socio-demographic factors.MethodsTelephone survey data from 5940 residents of 39 California cities were used to estimate social and demographic correlates of cannabis consumption. These individual-level estimates were then used to calculate aggregate cannabis demand (i.e. market potential) for 7538 census block groups. Locations of actively operating cannabis dispensaries were then related to the measure of demand and the socio-demographic characteristics of census block groups using multilevel Bayesian conditional autoregressive logit models.ResultsCannabis dispensaries were located in block groups with greater cannabis demand, higher rates of poverty, alcohol outlets, and in areas just outside city boundaries. For the sampled block groups, a 10% increase in demand within a block group was associated with 2.4% greater likelihood of having a dispensary, and a 10% increase in the city-wide demand was associated with a 6.7% greater likelihood of having a dispensary.ConclusionHigh demand for cannabis within individual block groups and within cities is related to the location of cannabis dispensaries at a block-group level. The relationship to low income, alcohol outlets and unincorporated areas indicates that dispensaries may open in areas that lack the resources to resist their establishment.     

Cannabis effects and dependency concerns in long-term frequent users: a missing piece of the public health puzzle

Based on structured interviews with 104 experienced users in Toronto, Canada, this article examines the perceived costs and benefits of cannabis consumption. A pretested questionnaire that was developed by Cohen and Sas (1998) in the Netherlands, and later translated for use in the U.S. and Germany as part of a three-city cross-national comparative study [(Reinarman et al. (2000). Is availability destiny? Drug use prevalence and discontinuance in Amsterdam, San Francisco and Bremen. Paper presented at the 11th International Conference on the Reduction of Drug-Related Harm, St. Helier, Jersey, Channel Islands, April 9–13, 2000; Cohen and Kaal (2001). The Irrelevance of Drug Policy: Patterns and Careers of Experienced Cannabis Use in the Populations of Amsterdam, San Francisco and Bremen. Centre for Drug Research, University of Amsterdam)] guided data collection on a range of drug effects, including measures of dependence inspired by DSM-IV criteria. The findings support a rational choice view of cannabis use insofar as reported advantages outweigh negative use outcomes. Top reasons for use pertain to relaxation and enhancement of recreational activities followed by coping with stress and anxiety. The frequency of respiratory and throat problems attributed to using cannabis underscores the perceived risk of pulmonary damage due to long-term heavy use. Whereas concerns about use levels nonetheless overshadowed other dependency indicators, including concern for personal health, however, no association was found between amounts nor frequency of use and the number of DSM-IV items reported by respondents. Users acknowledged and accepted the potential for dependence, adapting use levels accordingly when seen as problematic.     

Reprioritizing dependence and abuse: A comparison of cannabis clients in treatment with a nontreatment sample of users

Despite the growing literatures on cannabis dependence, and urgent declarations as to treatment need, there is a scarcity of data on cannabis problems as a primary reason for treatment. This article compares characteristics of cannabis treatment seekers with those of a nontreatment sample of users. Findings are reported from two independent studies that included items from the DSM-IV criteria for diagnosing substance dependence and abuse. Other survey items covered different drug reactions, both positive and negative, commonly attributed to cannabis consumption. Adverse reactions, as expected, were more often reported by users in treatment, and positive effects by those in the nontreatment group. Expected differences on DSM measures of impairment were least pronounced for symptoms of compulsion as compared to other problems of dependence or indicators of abuse. Put otherwise, adverse effects are more germane or distinctive to the treatment seeker's profile than dependence in and of itself. The findings are interpreted as evidence in favor of expanding harm reduction oriented treatment options to target cannabis misuse, or psychosocial and health problems, as opposed to “chronic” use of cannabis per se.     

A randomized controlled trial of a brief motivational enhancement for non-treatment-seeking adolescent cannabis users

Evidence for negative effects of early-onset cannabis use has led to a need for effective interventions targeting adolescent cannabis users. A randomized controlled trial of an Australian two-session intervention based on motivational interviewing (the ACCU, or Weed-Check in Dutch) was replicated in a larger Dutch sample of 119 non-treatment-seeking adolescent cannabis users. Outcome measures at the 3-month follow-up were quantity and frequency of cannabis use, symptoms of dependence, stage of change, and psychosocial functioning. Changes in all measures were in the expected direction, yet not significant. In moderation analyses, heavier cannabis users at baseline receiving the Weed-Check had greater reductions in cannabis use than those in the control condition. These results suggest that the Weed-Check might be beneficial for heavier cannabis-using adolescents. Further research is needed to confirm these results in a sample of adolescent heavy cannabis users and to examine the relationship between MI skills of prevention workers and outcome.     

Spatial working memory in heavy cannabis users: a functional magnetic resonance imaging study

Rationale Many neuropsychological studies have documented deficits in working memory among recent heavy cannabis users. However, little is known about the effects of cannabis on brain activity.Objective We assessed brain function among recent heavy cannabis users while they performed a working memory task.Methods Functional magnetic resonance imaging was used to examine brain activity in 12 long-term heavy cannabis users, 6–36 h after last use, and in 10 control subjects while they performed a spatial working memory task. Regional brain activation was analyzed and compared using statistical parametric mapping techniques.Results Compared with controls, cannabis users exhibited increased activation of brain regions typically used for spatial working memory tasks (such as prefrontal cortex and anterior cingulate). Users also recruited additional regions not typically used for spatial working memory (such as regions in the basal ganglia). These findings remained essentially unchanged when re-analyzed using subjects ages as a covariate. Brain activation showed little or no significant correlation with subjects years of education, verbal IQ, lifetime episodes of cannabis use, or urinary cannabinoid levels at the time of scanning.Conclusions Recent cannabis users displayed greater and more widespread brain activation than normal subjects when attempting to perform a spatial working memory task. This observation suggests that recent cannabis users may experience subtle neurophysiological deficits, and that they compensate for these deficits by working harder—calling upon additional brain regions to meet the demands of the task.     

Barriers to access for Canadians who use cannabis for therapeutic purposes

BackgroundThere is increased interest in the therapeutic potential of cannabis in recent decades. Canada, the Netherlands, Israel and some states in the United States have developed programs to allow access to cannabis for therapeutic purposes (CTP). In Canada, enrollment in the federal CTP program represents fewer than 5% of the estimated users of CTP. The discrepancy between the number of Canadians who report using CTP and the rate of utilization of the federal CTP program suggests the existence of barriers to access to this program.MethodsIn the present study we employ a health services analytical framework to examine barriers to access to CTP among 628 current CTP users. We define barriers to access as areas of poor fit between clients and services. We use five dimensions of accommodation, accessibility, availability, affordability, and acceptability to examine access to CTP.ResultsOur findings reveal that it is difficult for Canadians to find a physician to support their application to access CTP. Accessing CTP from unauthorized sources was common; only 7% of respondents accessed CTP exclusively from authorized sources. Access to CTP was positively associated with the presence of medical cannabis dispensaries, which were not included in the regulatory regime. Access to CTP varied by medical condition and general quality of health. Affordability of CTP was a substantial barrier to access.ConclusionsStrategies need to be developed to encourage scientific inquiry into CTP and address the barriers to access to CTP and the stigma and controversy that surround CTP and strain patient–physician relationships.     

Gender moderates the impact of stereotype threat on cognitive function in cannabis users

Research reveals mixed results for the effects of cannabis on cognitive functioning. These divergent results might stem from stereotype threat (ST), which occurs when individuals believe that a group to which they belong is inferior, resulting in poor test performance. Widespread media coverage of purported cannabis-related deficits in cognitive functioning may elicit ST among cannabis users, particularly among men, who may be more likely than women to identify with the cannabis-user stereotype. To investigate this hypothesis, cannabis users (30 male, 27 female) read a summary of research indicating either that cannabis produced deficits (ST condition), or that cannabis actually created no changes in cognitive functions. Participants then completed cognitive tests. Examination of the gender × condition interaction revealed significant results on 4 tests: the California Verbal Learning Test-II immediate recall task, the Controlled Oral Word Association Test for number of words generated and number of switches between clusters, and the Digit Symbol Substitution Task. Males exposed to ST performed worse on all tests compared to men not exposed to ST, while women exposed to ST performed better than women not exposed. These results suggest that cognitive deficits observed in male cannabis users may be attributed to ST rather than decreased functioning. Surprisingly, women in the ST condition scored higher than controls. Perhaps female users do not identify with the typical cannabis stereotype. This study highlights the importance of disconfirming relevant stereotypes prior to examination of the cognitive abilities of cannabis users.     

It ain't what you do,it's the way that you do it: A qualitative study of advice for young cannabis users

Introduction: Advice is a widely recommended and practised intervention with young drug users. Study of precisely how advice is given and received in any setting has, however, been limited. Design and Methods: We qualitatively analysed 106 audio‐recordings of advice sessions on cannabis use for young people within a randomised trial. Inductive data analysis was guided by a focus on practitioner behaviour which served to engage the active participation of the young drug user in the session. Results: A cluster of ‘Information Management’ activities was identified together with an ‘Interactive Orientation’ evident in a series of specific behaviours. Participants were most successfully engaged when both were combined, understood here as ‘Personalised Advice‐giving’. Discussion and Conclusions: These components identified in this exploratory study might assist further research in rectifying the absence of a solid empirical basis for effective practice in advice giving with young drug users and more widely.[Faulkner N, McCambridge J, Slym RL, Rollnick S. It ain't what you do, it's the way that you do it: A qualitative study of advice for young cannabis users. Drug Alcohol Rev 2009;28:129–134]     

Predicting the transition from frequent cannabis use to cannabis dependence: A three-year prospective study

Background

Frequent cannabis users are at high risk of dependence, still most (near) daily users are not dependent. It is unknown why some frequent users develop dependence, whereas others do not. This study aims to identify predictors of first-incidence DSM-IV cannabis dependence in frequent cannabis users.

Methods

A prospective cohort of frequent cannabis users (aged 18–30, n = 600) with baseline and two follow-up assessments (18 and 36 months) was used. Only participants without lifetime diagnosis of DSM-IV cannabis dependence at baseline (n = 269) were selected. Incidence of DSM-IV cannabis dependence was established using the Composite International Diagnostic Interview version 3.0. Variables assessed as potential predictors of the development of cannabis dependence included sociodemographic factors, cannabis use variables (e.g., motives, consumption habits, cannabis exposure), vulnerability factors (e.g., childhood adversity, family history of mental disorders or substance use problems, personality, mental disorders), and stress factors (e.g., life events, social support).

Results

Three-year cumulative incidence of cannabis dependence was 37.2% (95% CI = 30.7–43.8%). Independent predictors of the first incidence of cannabis dependence included: living alone, coping motives for cannabis use, number and type of recent negative life events (major financial problems), and number and type of cannabis use disorder symptoms (impaired control over use). Cannabis exposure variables and stable vulnerability factors did not independently predict first incidence of cannabis dependence.

Conclusions

In a high risk population of young adult frequent cannabis users, current problems are more important predictors of first incidence cannabis dependence than the level and type of cannabis exposure and stable vulnerability factors.     

Observations of the role of science in the United States medical cannabis state policies: Lessons learnt

BackgroundClinical trials have shown cannabis to be effective in the treatment of some medical conditions and there is mounting public and political pressure to enact laws enabling the use of cannabis for medicinal purposes. To date, 28 United States (U.S.) states and the District of Columbia have enacted medical cannabis laws. This study sought to identify the main issues pertaining to the development of medical cannabis laws in the U.S, including the role of scientific evidence.MethodsData were collected from three groups of participants: government officials, lobbyists and medical professionals involved in the medical cannabis debate in five selected states in the U.S.; researchers from the same five states conducting funded research in the alcohol and other drugs field; and members of the International Society for the Study of Drug Policy. The data were analysed using thematic analysis.ResultsSix major themes emerged in relation to the factors influencing policy: scientific evidence plays a limited role in the development of policy; the available research is limited and mixed; there is a need for clearer communication and active dissemination of evidence to policy makers; researchers need to consider what research is likely to impact on policy; scientific evidence is not a major factor in policy development; and there is a need to consider evidence within a political context.ConclusionResearchers need to be aware of the political context in which medical cannabis laws are or are not enacted and consider ways in which research findings can achieve a higher profile within this context.     

Cannabis for therapeutic purposes: Patient characteristics,access, and reasons for use

BackgroundThe authorized and unauthorized use of cannabis for therapeutic purposes (CTP) has increased dramatically in recent years, and physicians have called for further research to better clarify the parameters of effective and appropriate use. We report findings from a large cross-sectional study of the use of CTP in Canada and compare use across medical conditions and across authorized and unauthorized users.MethodsWe examined cannabis use history, medical conditions and symptoms, patterns of current use of CTP, modes of access and perceived effectiveness among 628 self-selected Canadians consumers of CTP. Participants were recruited from medical cannabis dispensaries and from organizations that assist users of CTP.ResultsPatients reported using cannabis to treat multiple symptoms, with sleep, pain, and anxiety being the most common. Cannabis was perceived to provide effective symptoms relief across medical conditions. Patterns of use were also consistent across medical conditions. Notable differences were observed with regard to modes of access.ConclusionAcross medical conditions respondents reported using cannabis to effectively address diverse symptoms. Results indicate a substantial disconnect between the therapeutic use of cannabis and research on the risks and benefits of such use; particularly with regard to the anxiolytic and sedative use of cannabis. Authorized and unauthorized users exhibited few meaningful differences with regard to medical conditions and patterns of use, but faced substantial differences regarding access.     

Overview of “home” cultivation policies and the case for community-based cannabis supply

BackgroundCannabis policies should be relevant to communities most impacted by them. Home cultivation policies can engage people who grow cannabis and build on their motivation to supply a safe product. This paper aims to examine the laws pertaining to “home” (i.e. personal, small-scale) cannabis cultivation internationally and their different aspects, and to discuss the potential of these policies to be expanded into community-level cannabis supply models.MethodsWe reviewed relevant laws and regulations in states/countries that legalised, decriminalised or applied other non-prohibitive approaches to home cannabis cultivation.FindingsNon-prohibitive approaches to home cannabis cultivation have been adopted in at least 27 jurisdictions. Twelve jurisdictions “de jure” legalised home cultivation (three U.S. states and Antigua and Barbuda legalised only home cultivation; six U.S. states, Uruguay and Canada legalised commercial sales as well). Eight states/countries “de facto” (Belgium, the Netherlands) or “de jure” decriminalised it (Czech Republic, Spain, Jamaica, and three Australian states). “De jure" depenalisation was in place in Chile and Brazil and recent court rulings yielded “de facto” depenalisation or “de facto” legalisation in five other jurisdictions (South Africa, Mexico, Colombia, Costa Rica and Georgia). Varying number of plants (per person and per property) and the circumstances of cultivation were in place. The key limitations of the regulations included (i) possession thresholds for the produce from home cultivations, (ii) rules about sharing the produce, and (iii) potentially disproportionate sanctions for non-authorised behaviours. Despite currently being limited, home cultivation policies might have the capacity to engage cannabis networks that already exist in the community and like that, enhance their participation in legitimate policy schemes.ConclusionsRules around pooled cultivation and sharing could be made fit for purpose to accommodate community supply of cannabis. Home cultivation policies could serve as a basis for community-level cannabis supply models and as such, for more inclusive cannabis policies.     

Exploratory study of the psychopathological profiles of adolescent cannabis users

Although adolescent cannabis users have been reported not to be a homogeneous group, they are few typological studies and only one based on psychopathological variables. A better knowledge of the typology of cannabis users might contribute to the identification of specific needs concerning prevention or treatment. Among 199 adolescents using cannabis at least monthly during the last six month, cluster analysis yielded three clusters based on depressive symptoms, social anxiety, borderline personality traits, and psychopathic traits (impulsivity and callous-unemotional traits). The largest cluster, called 'ordinary' was well below the mean on all measures. Another cluster, labeled 'borderline' was distinguished by high levels of borderline traits, depressed mood, and social anxiety. The smallest cluster, called 'impulsive' was well above the mean in impulsivity and callous traits but low on all other measures. Frequency of cannabis use was higher in the borderline and impulsive clusters than in the ordinary cluster. Multiple regression analyses suggested that the contributions of psychopathological variables to cannabis use varied across clusters.     

Pattern of cannabis use in ecstasy polydrug users: moderate cannabis use may compensate for self-rated aggression and somatic symptoms

Cannabis is one of the most common 'co-drugs' for ecstasy users. The aim of the present study was to explore self-reported psychobiological problems in ecstasy polydrug users in relation to their pattern of cannabis use. Two hundred and eighty ecstasy polydrug users were allocated into five cannabis groups according to the frequency of their cannabis use. The control group comprised 121 alcohol-tobacco users. There were no significant group differences with regard to age, diagnosed family psychiatric history and level of self-rated stress experienced during 6 months prior to the study. The present study produced three main findings: (a) Ecstasy users with no concomitant use of cannabis displayed more self-rated aggression and somatic symptoms compared with ecstasy users who were smoking cannabis on a monthly or weekly basis. (b) Ecstasy users who reported heavy cannabis use in the past displayed higher paranoid symptoms compared with ecstasy weekly and daily cannabis users. (c) Former heavy cannabis users were the most likely to complain of a variety of ecstasy related long-term problems. In conclusion, moderate cannabis use may help to ameliorate or mask MDMA-induced aggressivity and somatic symptoms. However, this study confirms that heavy cannabis and ecstasy use is associated with several psychobiological problems, which may emerge after a period of abstinence from both drugs.