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Sample records for adolescent cannabis users

  1. The Motivational Enhancement Therapy and Cognitive Behavioral Therapy Supplement: 7 Sessions of Cognitive Behavioral Therapy for Adolescent Cannabis Users, Cannabis Youth Treatment (CYT) Series, Volume 2.

    ERIC Educational Resources Information Center

    Webb, Charles; Scudder, Meleney; Kaminer, Yifrah; Kaden, Ron

    This manual, a supplement to "Motivational Enhancement Therapy and Cognitive Behavioral Therapy for Adolescent Cannabis Users: 5 Sessions, Cannabis Youth Treatment (CYT) Series, Volume 1", presents a seven-session cognitive behavioral treatment (CBT7) approach designed especially for adolescent cannabis users. It addresses the implementation and…

  2. The Adolescent Community Reinforcement Approach for Adolescent Cannabis Users, Cannabis Youth Treatment (CYT) Series, Volume 4.

    ERIC Educational Resources Information Center

    Godley, Susan Harrington; Meyers, Robert J.; Smith, Jane Ellen; Karvinen, Tracy; Titus, Janet C.; Godley, Mark D.; Dent, George; Passetti, Lora; Kelberg, Pamela

    This publication was written for therapists and their supervisors who may want to implement the adolescent community reinforcement approach intervention, which was one of the five interventions tested by the Center for Substance Abuse Treatment's (CSAT's) Cannabis Youth Treatment (CYT) Project. The CYT Project provided funding to support a study…

  3. The Importance of Family Relations for Cannabis Users: The Case of Serbian Adolescents

    PubMed Central

    TERZIC SUPIC, Zorica; SANTRIC MILICEVIC, Milena; SBUTEGA, Isidora; VASIC, Vladimir

    2013-01-01

    Background Adolescence is transitional stage of physical and mental human development occuring between childhood and adult life. Social interactions and environmental factors together are important predictors of adolescent cannabis use. This study aimed to examine the relationship between the social determinants and adolescents behavior with cannabis consumption. Methods: A cross sectional study as part of the European School Survey Project on Alcohol and other Drugs was conducted among 6.150 adolescents aged 16 years in three regions of Serbia, and three types of schools (gymnasium, vocational – professional, and vocational – handicraft) during May – June 2008. A multivariate logistic regression analysis was carried out to obtain adjusted odds ratios with 95% confidence intervals in which the dependent variable was cannabis consumption non-user and user. Results: Among 6.7% of adolescents who had tried cannabis at least one in their lives, boys were more involved in cannabis use than girls, especially boys from gymnasium school. Well off family, lower education of mother, worse relations with parents were significantly associated with cannabis use (P < 0.05). Behaviors like skipping from schools, frequent evening outs, and playing on slot machines were also related to cannabis use (P < 0.05). Conclusions: The study confirmed the importance of family relationship development. Drug use preventive programmes should include building interpersonal trust in a family lifecycle and school culture. PMID:23641402

  4. Response inhibition and elevated parietal-cerebellar correlations in chronic adolescent cannabis users.

    PubMed

    Behan, B; Connolly, C G; Datwani, S; Doucet, M; Ivanovic, J; Morioka, R; Stone, A; Watts, R; Smyth, B; Garavan, H

    2014-09-01

    The ability to successfully inhibit an inappropriate behaviour is a crucial component of executive functioning and its impairment has been linked to substance dependence. Cannabis is the most widely used illicit drug in adolescence and, given the accelerated neuromaturation during adolescence, it is important to determine the effects of cannabis use on neurocognitive functioning during this developmental period. In this study, a cohort of adolescent heavy cannabis users and age-matched non-cannabis-using controls completed a Go/No-Go paradigm. Users were impaired in performance on the task but voxelwise and region-of-interest comparisons revealed no activation differences between groups. Instead, an analysis of correlation patterns between task-activated areas revealed heightened correlation scores in the users between bilateral inferior parietal lobules and the left cerebellum. The increased correlation activity between these regions was replicated with resting state fMRI data and was positively correlated with self-reported, recent cannabis usage. The results suggests that the poorer inhibitory control of adolescent cannabis users might be related to aberrant connectivity between nodes of the response inhibition circuit and that this effect is observable in both task-induced and intrinsic correlation patterns. This article is part of the Special Issue Section entitled 'Neuroimaging in Neuropharmacology'.

  5. A preliminary evaluation of synthetic cannabinoid use among adolescent cannabis users: Characteristics and treatment outcomes.

    PubMed

    Blevins, Claire E; Banes, Kelsey E; Stephens, Robert S; Walker, Denise D; Roffman, Roger A

    2016-12-01

    Little is known regarding the use of synthetic cannabinoids (SC), particularly use among adolescent substance users who may be at higher risk. The present exploratory study seeks to describe SC use and subjective effects among cannabis-using adolescents as well as compare the characteristics of cannabis users who do and do not use SC. Exploratory analyses evaluated cannabis treatment outcomes among SC users and non-users. Participants enrolled in a randomized, controlled intervention for cannabis-using high school students aged 14-19 (N=252) completed questionnaires regarding their use of SC and other substances. Those who used SC in the past 60days reported subjective effects of SC, consequences, and SC use disorder symptoms. Baseline characteristics, alcohol and other drug use, and treatment outcomes of SC users were compared to participants who never tried SC. Within this sample 29% had tried SC, and 6% used SC recently. Although most reported use at a relatively low rate, 43% of recent SC users reported SC use-disorder symptoms. Positive and negative subjective effects of SC were endorsed, with positive subjective effects reported more often. SC use was associated with more cannabis use, but not more alcohol or other (non-SC and non-cannabis) drug use. SC users did not differ from non-users on cannabis treatment outcomes. This exploratory study described SC use, and compared characteristics and treatment outcomes among SC users and non-users. Negative subjective effects of SC were reported as occurring less often, but SC use was associated with use disorder psychopathology. SC use was associated with more problematic cannabis use at baseline, but was not associated with use of other substances or differences in treatment outcome.

  6. Latent Classes of Substance Use in Adolescent Cannabis Users: Predictors and Subsequent Substance-Related Harm

    PubMed Central

    Fallu, Jean-Sébastien; Brière, Frédéric N.; Janosz, Michel

    2014-01-01

    Cannabis use is highly prevalent in late adolescence, but not all users experience significant negative consequences. Little information is available to identify the substance use patterns and risk factors of users who are at greater risk of experiencing negative consequences. In this prospective study, we aimed to empirically identify latent classes of substance use in adolescent cannabis users and to examine how these classes relate to antecedent psychosocial predictors and subsequent substance-related outcomes. The sample was recruited from 68 high schools in Quebec and consisted of 1618 participants who reported using cannabis in grade 10. We used latent class analysis to empirically identify classes of users based on the age of onset, frequency, and typical quantity of cannabis and other substance use, as well as substance mixing behaviors. We then compared classes in terms of (a) sociodemographic and psychosocial predictors in grades 7–8 and (b) substance-related consequences in grade 11. Four distinct classes were identified: Late-Light Users (28%); Late-Heavy + Polydrug Users (14%); Early-Moderate Users (33%); Early-Heavy + Polydrug Users (26%). Late-Light Users reported the lowest levels of substance use, while Early-Heavy + Polydrug Users reported the highest levels. Intermediate levels of substance use were found in the other two classes. Sex, age, delinquency, peer delinquency, school bonding, parental monitoring, and parental conflict all helped to differentiate classes. Class membership predicted substance-related harm, with greater consequences in early- and late-onset heavy using classes. In light of results, in addition to age and sex, screening and intervention for risky cannabis use among adolescents should focus on school bonding in order to target the most risky late-onset adolescents and on peer delinquency in order to target the most risky early-onset ones. PMID:24570663

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

    PubMed

    de Gee, Elisabeth A; Verdurmen, Jacqueline E E; Bransen, Els; de Jonge, Jannet M; Schippers, Gerard M

    2014-09-01

    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.

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

    PubMed

    de Gee, Elisabeth A; Verdurmen, Jacqueline E E; Bransen, Els; de Jonge, Jannet M; Schippers, Gerard M

    2014-09-01

    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. PMID:24969735

  9. Altered cerebral blood flow and neurocognitive correlates in adolescent cannabis users

    PubMed Central

    Jacobus, Joanna; Goldenberg, Diane; Wierenga, Christina E.; Tolentino, Neil J.; Liu, Thomas T.

    2012-01-01

    Rationale The effects of adolescent marijuana use on the developing brain remain unclear, despite its prevalence. Arterial spin labeling (ASL) is a noninvasive imaging technique that characterizes neurovascular status and cerebral blood flow (CBF), potentially revealing contributors to neuropathological alterations. No studies to date have looked at CBF in adolescent marijuana users. Objectives This study examined CBF in adolescent marijuana users and matched healthy controls at baseline and after 4 weeks of monitored abstinence. Methods Heavy adolescent marijuana users (n=23, >200 lifetime marijuana use days) and demographically matched controls (n=23) with limited substance exposure underwent an ASL brain scan at an initial session and after 4 weeks of sequential urine toxicology to confirm abstinence. Results Marijuana users showed reduced CBF in four cortical regions including the left superior and middle temporal gyri, left insula, left and right medial frontal gyrus, and left supramarginal gyrus at baseline; users showed increased CBF in the right precuneus at baseline, as compared to controls (corrected p values<0.05). No between group differences were found at follow-up. Conclusions Marijuana use may influence CBF in otherwise healthy adolescents acutely; however, group differences were not observed after several weeks of abstinence. Neurovascular alterations may contribute to or underlie changes in brain activation, neuropsychological performance, and mood observed in young cannabis users with less than a month of abstinence. PMID:22395430

  10. Multidimensional Family Therapy for Adolescent Cannabis Users, Cannabis Youth Treatment (CYT) Series, Volume 5.

    ERIC Educational Resources Information Center

    Liddle, Howard A.

    The purpose of the Substance Abuse and Mental Health Services Administration's Center for Substance Abuse Treatment's (CSAT's) Cannabis Youth Treatment (CYT) Project Cooperative Agreement was to test the relative effectiveness and cost-effectiveness of a variety of interventions designed to eliminate marijuana use and associated problems in…

  11. Motivational Enhancement Therapy and Cognitive Behavioral Therapy for Adolescent Cannabis Users: 5 Sessions. Cannabis Youth Treatment (CYT) Series, Volume 1.

    ERIC Educational Resources Information Center

    Sampl, Susan; Kadden, Ronald

    This manual is designed to help train substance abuse treatment counselors to conduct a brief five-session treatment intervention for adolescents with cannabis use disorders presenting for outpatient treatment. It combines two sessions of motivational enhancement therapy provided individually and three sessions of cognitive behavioral therapy…

  12. Family Support Network for Adolescent Cannabis Users, Cannabis Youth Treatment (CYT) Series, Volume 3.

    ERIC Educational Resources Information Center

    Hamilton, Nancy L.; Brantley, Laura Bunch; Tims, Frank M.; Angelovich, Nancy; McDougall, Barbara

    Substance-abusing adolescents experiencing inadequate family structure and functioning will be at a serious disadvantage with regard to recovery. The family support network (FSN) intervention seeks to extend the focus of treatment beyond the world of the adolescent by engaging the family, a major system in his or her life. Designed to increase…

  13. Structural and Functional Imaging Studies in Chronic Cannabis Users: A Systematic Review of Adolescent and Adult Findings

    PubMed Central

    Batalla, Albert; Bhattacharyya, Sagnik; Yücel, Murat; Fusar-Poli, Paolo; Crippa, Jose Alexandre; Nogué, Santiago; Torrens, Marta; Pujol, Jesús; Farré, Magí; Martin-Santos, Rocio

    2013-01-01

    Background The growing concern about cannabis use, the most commonly used illicit drug worldwide, has led to a significant increase in the number of human studies using neuroimaging techniques to determine the effect of cannabis on brain structure and function. We conducted a systematic review to assess the evidence of the impact of chronic cannabis use on brain structure and function in adults and adolescents. Methods Papers published until August 2012 were included from EMBASE, Medline, PubMed and LILACS databases following a comprehensive search strategy and pre-determined set of criteria for article selection. Only neuroimaging studies involving chronic cannabis users with a matched control group were considered. Results One hundred and forty-two studies were identified, of which 43 met the established criteria. Eight studies were in adolescent population. Neuroimaging studies provide evidence of morphological brain alterations in both population groups, particularly in the medial temporal and frontal cortices, as well as the cerebellum. These effects may be related to the amount of cannabis exposure. Functional neuroimaging studies suggest different patterns of resting global and brain activity during the performance of several cognitive tasks both in adolescents and adults, which may indicate compensatory effects in response to chronic cannabis exposure. Limitations However, the results pointed out methodological limitations of the work conducted to date and considerable heterogeneity in the findings. Conclusion Chronic cannabis use may alter brain structure and function in adult and adolescent population. Further studies should consider the use of convergent methodology, prospective large samples involving adolescent to adulthood subjects, and data-sharing initiatives. PMID:23390554

  14. Cannabis Use Disorder in Adolescence.

    PubMed

    Simpson, Annabelle K; Magid, Viktoriya

    2016-07-01

    Cannabis use in the adolescent population poses a significant threat of addiction potential resulting in altered neurodevelopment. There are multiple mechanisms of treatment of cannabis use disorder including behavioral therapy management and emerging data on treatment via pharmacotherapy. Recognizing the diagnostic criteria for cannabis use disorder, cannabis withdrawal syndrome, and mitigating factors that influence adolescent engagement in cannabis use allows for comprehensive assessment and management in the adolescent population.

  15. Cannabis Use Disorder in Adolescence.

    PubMed

    Simpson, Annabelle K; Magid, Viktoriya

    2016-07-01

    Cannabis use in the adolescent population poses a significant threat of addiction potential resulting in altered neurodevelopment. There are multiple mechanisms of treatment of cannabis use disorder including behavioral therapy management and emerging data on treatment via pharmacotherapy. Recognizing the diagnostic criteria for cannabis use disorder, cannabis withdrawal syndrome, and mitigating factors that influence adolescent engagement in cannabis use allows for comprehensive assessment and management in the adolescent population. PMID:27338965

  16. Cannabis and adolescent brain development.

    PubMed

    Lubman, Dan I; Cheetham, Ali; Yücel, Murat

    2015-04-01

    Heavy cannabis use has been frequently associated with increased rates of mental illness and cognitive impairment, particularly amongst adolescent users. However, the neurobiological processes that underlie these associations are still not well understood. In this review, we discuss the findings of studies examining the acute and chronic effects of cannabis use on the brain, with a particular focus on the impact of commencing use during adolescence. Accumulating evidence from both animal and human studies suggests that regular heavy use during this period is associated with more severe and persistent negative outcomes than use during adulthood, suggesting that the adolescent brain may be particularly vulnerable to the effects of cannabis exposure. As the endocannabinoid system plays an important role in brain development, it is plausible that prolonged use during adolescence results in a disruption in the normative neuromaturational processes that occur during this period. We identify synaptic pruning and white matter development as two processes that may be adversely impacted by cannabis exposure during adolescence. Potentially, alterations in these processes may underlie the cognitive and emotional deficits that have been associated with regular use commencing during adolescence. PMID:25460036

  17. Cannabis and adolescent brain development.

    PubMed

    Lubman, Dan I; Cheetham, Ali; Yücel, Murat

    2015-04-01

    Heavy cannabis use has been frequently associated with increased rates of mental illness and cognitive impairment, particularly amongst adolescent users. However, the neurobiological processes that underlie these associations are still not well understood. In this review, we discuss the findings of studies examining the acute and chronic effects of cannabis use on the brain, with a particular focus on the impact of commencing use during adolescence. Accumulating evidence from both animal and human studies suggests that regular heavy use during this period is associated with more severe and persistent negative outcomes than use during adulthood, suggesting that the adolescent brain may be particularly vulnerable to the effects of cannabis exposure. As the endocannabinoid system plays an important role in brain development, it is plausible that prolonged use during adolescence results in a disruption in the normative neuromaturational processes that occur during this period. We identify synaptic pruning and white matter development as two processes that may be adversely impacted by cannabis exposure during adolescence. Potentially, alterations in these processes may underlie the cognitive and emotional deficits that have been associated with regular use commencing during adolescence.

  18. Altered Frontal Cortical Volume and Decision Making in Adolescent Cannabis Users

    PubMed Central

    Churchwell, John C.; Lopez-Larson, Melissa; Yurgelun-Todd, Deborah A.

    2010-01-01

    Anticipating future outcomes is central to decision making and a failure to consider long-term consequences may lead to impulsive choices. Adolescence is a vulnerable period during which underdeveloped prefrontal cortical systems may contribute to poor judgment, impulsive choices, and substance abuse. Conversely, substance abuse during this period may alter neural systems involved in decision making and lead to greater impulsivity. Although a broad neural network which supports decision making undergoes extensive change during adolescent development, one region that may be critical is the medial prefrontal cortex. Altered functional integrity of this region may be specifically related to reward perception, substance abuse, and dependence. In the present investigation, we acquired structural magnetic resonance images (MRI), using a 3T Siemens Trio scanner, from 18 cannabis abusing adolescents (CA; 2 female and 16 male subjects; mean age, 17.7 years; range 16–19 years), and 18 healthy controls (HC; 6 female and 12 male subjects; mean age, 17.2 years; range 16–19 years). In order to measure medial orbital prefrontal cortex (moPFC) morphology related to substance abuse and impulsivity, semi-automated cortical reconstruction and volumetric segmentation of MRIs was performed with FreeSurfer. Impulsivity was evaluated with the Barratt Impulsiveness Scale (BIS). Our results indicate that cannabis abusing adolescents have decreased right moPFC volume compared to controls, p = 0.01, d = 0.92, CI0.95 = 0.21, 1.59. Cannabis abusing adolescents also show decreased future orientation, as indexed by the BIS non-planning subscale, when compared to controls, p = 0.01, d = 0.89, CI0.95 = 0.23, 1.55. Moreover, total moPFC volume was positively correlated with age of first use r (18) = 0.49, p < 0.03, suggesting that alterations in this region may be related to initiation of cannabis use or that early initiation may lead to reduced moPFC volume

  19. Randomized controlled trial of motivational enhancement therapy with nontreatment-seeking adolescent cannabis users: a further test of the teen marijuana check-up.

    PubMed

    Walker, Denise D; Stephens, Robert; Roffman, Roger; Demarce, Josephine; Lozano, Brian; Towe, Sheri; Berg, Belinda

    2011-09-01

    Cannabis use adversely affects adolescents and interventions that are attractive to adolescents are needed. This trial compared the effects of a brief motivational intervention for cannabis use with a brief educational feedback control and a no-assessment control. Participants were randomized into one of three treatment conditions: Motivational Enhancement Therapy (MET), Educational Feedback Control (EFC), or Delayed Feedback Control (DFC). Those who were assigned to MET and EFC were administered a computerized baseline assessment immediately following randomization and completed assessments at the 3- and 12-month follow-up periods. Participants in the DFC condition were not assessed until the 3-month follow-up. Following the completion of treatment sessions, all participants were offered up to four optional individual treatment sessions aimed at cessation of cannabis use. The research was conducted in high schools in Seattle, Washington. The participant s included 310 self-referred adolescents who smoked cannabis regularly. The main outcome measures included days of cannabis use, associated negative consequences, and engagement in additional treatment. At the 3-month follow-up, participants in both the MET and EFC conditions reported significantly fewer days of cannabis use and negative consequences compared to those in the DFC. The frequency of cannabis use was less in MET relative to EFC at 3 months, but it did not translate to differences in negative consequences. Reductions in use and problems were sustained at 12 months, but there were no differences between MET and EFC interventions. Engagement in additional treatment was minimal and did not differ by condition. Brief interventions can attract adolescent cannabis users and have positive impacts on them, but the mechanisms of the effects are yet to be identified.

  20. "CAN Stop" - Implementation and evaluation of a secondary group prevention for adolescent and young adult cannabis users in various contexts - study protocol

    PubMed Central

    2011-01-01

    Background Current research shows that overall numbers for cannabis use among adolescents and young adults dropped in recent years. However, this trend is much less pronounced in continuous cannabis use. With regard to the heightened risk for detrimental health- and development-related outcomes, adolescents and young adults with continuous cannabis use need special attention. The health services structure for adolescents and young adults with substance related problems in Germany, is multifaceted, because different communal, medical and judicial agencies are involved. This results in a rather decentralized organizational structure of the help system. This and further system-inherent characteristics make the threshold for young cannabis users rather high. Because of this, there is a need to establish evidence-based low-threshold help options for young cannabis users, which can be easily disseminated. Therefore, a training programme for young cannabis users (age 14-21) was developed in the "CAN Stop" project. Within the project, we seek to implement and evaluate the training programme within different institutions of the help system. The evaluation is sensitive to the different help systems and their specific prerequisites. Moreover, within this study, we also test the practicability of a training provision through laypersons. Methods/Design The CAN Stop study is a four-armed randomized wait-list controlled trial. The four arms are needed for the different help system settings, in which the CAN Stop training programme is evaluated: (a) the drug addiction aid and youth welfare system, (b) the out-patient medical system, (c) the in-patient medical system and (d) prisons for juvenile offenders. Data are collected at three points, before and after the training or a treatment as usual, and six months after the end of either intervention. Discussion The CAN Stop study is expected to provide an evidence-based programme for young cannabis users seeking to reduce or quit

  1. Exposure to Cannabis in Popular Music and Cannabis Use among Adolescents

    PubMed Central

    Primack, Brian A.; Douglas, Erika L.; Kraemer, Kevin L.

    2009-01-01

    Background Cannabis use is frequently referenced in American popular music, yet it remains uncertain whether exposure to these references is associated with actual cannabis use. We aimed to determine if exposure to cannabis in popular music is independently associated with current cannabis use in a cohort of urban adolescents. Methods We surveyed all 9th grade students at three large U.S. urban high schools. We estimated participants’ exposure to lyrics referent to cannabis with overall music exposure and content analyses of their favorite artists’ songs. Outcomes included current (past 30 day) and ever use of cannabis. We used multivariable regression to assess independent associations between exposures and outcomes while controlling for important covariates. Results Each of the 959 participants was exposed to an estimated 40 cannabis references per day (standard deviation = 104). Twelve percent (N = 108) were current cannabis users and 32% (N=286) had ever used cannabis. Compared with those in the lowest tertile of total cannabis exposure in music, those in the highest tertile of exposure were almost twice as likely to have used cannabis in the past 30 days (odds ratio = 1.83; 95% confidence interval = 1.04, 3.22), even after adjusting for sociodemographic variables, personality characteristics, and parenting style. As expected, however, there was no significant relationship between our cannabis exposure variable and a sham outcome variable of alcohol use. Conclusions This study supports an independent association between exposure to cannabis in popular music and early cannabis use among urban American adolescents. PMID:20039860

  2. [Internalizing problem behaviour and cannabis use: associations and variables of influence in a cross-sectional study of 14- to 23 year old cannabis users].

    PubMed

    Baldus, Christiane; Haevelmann, Andrea; Reis, Olaf; Thomasius, Rainer

    2014-01-01

    Regarding the association between internalizing problem behaviour and cannabis use in adolescents and young adults, several studies were published in recent time. Using cross-sectional data from adolescent and young adult cannabis users of the project "CAN Stop" (n = 239; age 14-23), associations between internalizing problem behaviour, cannabis effects expectancies, number of psychosocial problems and severity of dependence were analysed with an age- and gender-sensitive perspective. By describing young cannabis users, we seek to deepen the understanding of the association between cannabis use and internalizing problem behaviour. Cannabis users with normal-range YSR/YASR-profiles, internalizing problem behaviour, externalizing problem behaviour or combined problems differ significantly regarding their age of first cannabis use, age of regular cannabis use and number of both cannabis and alcohol use days. Regarding cannabis effects expectancies, cannabis users with externalizing problem behaviour show a broader variation of positive expectancies. Internalizing problems were associated with impairing and sedating effects expectancies. PMID:24707768

  3. [Internalizing problem behaviour and cannabis use: associations and variables of influence in a cross-sectional study of 14- to 23 year old cannabis users].

    PubMed

    Baldus, Christiane; Haevelmann, Andrea; Reis, Olaf; Thomasius, Rainer

    2014-01-01

    Regarding the association between internalizing problem behaviour and cannabis use in adolescents and young adults, several studies were published in recent time. Using cross-sectional data from adolescent and young adult cannabis users of the project "CAN Stop" (n = 239; age 14-23), associations between internalizing problem behaviour, cannabis effects expectancies, number of psychosocial problems and severity of dependence were analysed with an age- and gender-sensitive perspective. By describing young cannabis users, we seek to deepen the understanding of the association between cannabis use and internalizing problem behaviour. Cannabis users with normal-range YSR/YASR-profiles, internalizing problem behaviour, externalizing problem behaviour or combined problems differ significantly regarding their age of first cannabis use, age of regular cannabis use and number of both cannabis and alcohol use days. Regarding cannabis effects expectancies, cannabis users with externalizing problem behaviour show a broader variation of positive expectancies. Internalizing problems were associated with impairing and sedating effects expectancies.

  4. [Decision making in cannabis users].

    PubMed

    Alameda Bailén, Jose Ramón; Paíno Quesada, Susana; Mogedas Valladares, Ana Isabel

    2012-01-01

    Several neuropsychological studies have shown that chronic cannabis users have cognitive impairments, including decision-making process. Therefore, this study aims to evaluate the process, through the somatic marker hypothesis in a sample of 41 cannabis users compared with a control group of equal size, and to analyze the influence of age, sex, education level, age of onset and amount of daily consumption. In order to do that, the software "Cartas" (similar to the Iowa Gambling Task), was used, implementing its two versions: normal and reverse. The results show significant differences between cannabis users and control group in the normal and reverse task execution. By block analysis, the control group obtained higher scores in the normal task execution, however, in the reverse task, the differences between groups are present in the initial task execution but not final task execution. None of the analyzed variables (age, sex ...) are significantly related to task performance. These results suggest the existence of alterations in the decision making process of consumers cannabis, which may relate to the difficulty in generating somatic markers, and not for insensitivity punishments insensitivity.

  5. Cannabis Use and Performance in Adolescents

    ERIC Educational Resources Information Center

    Malhotra, Anil; Biswas, Parthasarathy

    2006-01-01

    Cannabis is a widely used illicit drug among adolescents, many of whom perceive little risk from cannabis. Cannabis use is associated with poor academic performance and increased school drop-outs. It is also associated with high-risk behaviors in adolescents like crime, violence, unprotected sexual encounters, and car accidents. Many of these…

  6. Poor School Satisfaction and Number of Cannabis Using Peers within School Classes as Individual Risk Factors for Cannabis Use among Adolescents

    ERIC Educational Resources Information Center

    Hoff, Dominic A.; Andersen, Anette; Holstein, Bjorn E.

    2010-01-01

    There is little information available on the topic of poor school satisfaction as a risk factor for cannabis use among adolescents. We examined if there was an association between poor school satisfaction, school class cannabis use and individual cannabis use. Further, we investigated if many cannabis users within the school class statistically…

  7. Cannabis Use during Adolescent Development: Susceptibility to Psychiatric Illness.

    PubMed

    Chadwick, Benjamin; Miller, Michael L; Hurd, Yasmin L

    2013-10-14

    Cannabis use is increasingly pervasive among adolescents today, even more common than cigarette smoking. The evolving policy surrounding the legalization of cannabis reaffirms the need to understand the relationship between cannabis exposure early in life and psychiatric illnesses. cannabis contains psychoactive components, notably Δ(9)-tetrahydrocannabinol (THC), that interfere with the brain's endogenous endocannabinoid system, which is critically involved in both pre- and post-natal neurodevelopment. Consequently, THC and related compounds could potentially usurp normal adolescent neurodevelopment, shifting the brain's developmental trajectory toward a disease-vulnerable state, predisposing early cannabis users to motivational, affective, and psychotic disorders. Numerous human studies, including prospective longitudinal studies, demonstrate that early cannabis use is associated with major depressive disorder and drug addiction. A strong association between schizophrenia and cannabis use is also apparent, especially when considering genetic factors that interact with this environmental exposure. These human studies set a foundation for carefully controlled animal studies which demonstrate similar patterns following early cannabinoid exposure. Given the vulnerable nature of adolescent neurodevelopment and the persistent changes that follow early cannabis exposure, the experimental findings outlined should be carefully considered by policymakers. In order to fully address the growing issues of psychiatric illnesses and to ensure a healthy future, measures should be taken to reduce cannabis use among teens.

  8. Statistics on Cannabis Users Skew Perceptions of Cannabis Use

    PubMed Central

    Burns, Rachel M.; Caulkins, Jonathan P.; Everingham, Susan S.; Kilmer, Beau

    2013-01-01

    Collecting information about the prevalence of cannabis use is necessary but not sufficient for understanding the size, dynamics, and outcomes associated with cannabis markets. This paper uses two data sets describing cannabis consumption in the United States and Europe to highlight (1) differences in inferences about sub-populations based on the measure used to quantify cannabis-related activity; (2) how different measures of cannabis-related activity can be used to more accurately describe trends in cannabis usage over time; and (3) the correlation between frequency of use in the past-month and average grams consumed per use-day. Key findings: focusing on days of use instead of prevalence shows substantially greater increases in U.S. cannabis use in recent years; however, the recent increase is mostly among adults, not youth. Relatively more rapid growth in use days also occurred among the college-educated and Hispanics. Further, data from a survey conducted in seven European countries show a strong positive correlation between frequency of use and quantity consumed per day of use, suggesting consumption is even more skewed toward the minority of heavy users than is suggested by days-of-use calculations. PMID:24223560

  9. Implicit Associations and Explicit Expectancies toward Cannabis in Heavy Cannabis Users and Controls

    PubMed Central

    Beraha, Esther M.; Cousijn, Janna; Hermanides, Elisa; Goudriaan, Anna E.; Wiers, Reinout W.

    2013-01-01

    Cognitive biases, including implicit memory associations are thought to play an important role in the development of addictive behaviors. The aim of the present study was to investigate implicit affective memory associations in heavy cannabis users. Implicit positive-arousal, sedation, and negative associations toward cannabis were measured with three Single Category Implicit Association Tests (SC-IAT’s) and compared between 59 heavy cannabis users and 89 controls. Moreover, we investigated the relationship between these implicit affective associations and explicit expectancies, subjective craving, cannabis use, and cannabis related problems. Results show that heavy cannabis users had stronger implicit positive-arousal associations but weaker implicit negative associations toward cannabis compared to controls. Moreover, heavy cannabis users had stronger sedation but weaker negative explicit expectancies toward cannabis compared to controls. Within heavy cannabis users, more cannabis use was associated with stronger implicit negative associations whereas more cannabis use related problems was associated with stronger explicit negative expectancies, decreasing the overall difference on negative associations between cannabis users and controls. No other associations were observed between implicit associations, explicit expectancies, measures of cannabis use, cannabis use related problems, or subjective craving. These findings indicate that, in contrast to other substances of abuse like alcohol and tobacco, the relationship between implicit associations and cannabis use appears to be weak in heavy cannabis users. PMID:23801968

  10. Assessing Topographical Orientation Skills in Cannabis Users

    PubMed Central

    Palermo, Liana; Bianchini, Filippo; Iaria, Giuseppe; Tanzilli, Antonio; Guariglia, Cecilia

    2012-01-01

    The long-term effects of cannabis on human cognition are still unclear, but, considering that cannabis is a widely used substance and, overall, its potential use in therapeutic interventions, it is important to evaluate them. We hypothesize that the discrepancies among studies could be attributed to the specific cognitive function investigated and that skills subserved by the hippocampus, such as the spatial orientation abilities and, specifically, the ability to form and use cognitive maps, should be more compromised than others. Indeed it has been showed that cannabis users have a reduced hippocampus and that the hippocampus is the brain region in which cannabis has the greatest effect since it contains the highest concentration of cannabinoid receptors. To test this hypothesis we asked 15 heavy cannabis users and 19 nonusers to perform a virtual navigational test, the CMT, that assesses the ability to form and use cognitive maps. We found that using cannabis has no effect on these hippocampus-dependent orientation skills. We discuss the implications of our findings and how they relate to evidence reported in the literature that the intervention of functional reorganization mechanisms in cannabis user allows them to cope with the cognitive demands of navigational tasks. PMID:22272167

  11. Dissociation between implicit and explicit expectancies of cannabis use in adolescence.

    PubMed

    Schmits, Emilie; Maurage, Pierre; Thirion, Romain; Quertemont, Etienne

    2015-12-30

    Cannabis is one of the most commonly drugs used by teenagers. Expectancies about its effects play a crucial role in cannabis consumption. Various tools have been used to assess expectancies, mainly self-report questionnaires measuring explicit expectancies, but implicit measures based on experimental tasks have also been developed, measuring implicit expectancies. The aim of this study was to simultaneously assess implicit/explicit expectancies related to cannabis among adolescent users and non-users. 130 teenagers attending school (55 girls) were enrolled (Age: M=16.40 years); 43.84% had never used cannabis ("non-users") and 56.16% had used cannabis ("users"). They completed self-report questionnaires evaluating cannabis use, cannabis-related problems, effect expectancies (explicit expectancies), alcohol use, social and trait anxiety, depression, as well as three Implicit Association Tests (IAT) assessing implicit expectancies. Adolescents manifested more implicit affective associations (relaxation, excitation, negative) than neutral ones regarding cannabis. These were not related to explicit expectancies. Cannabis users reported more implicit relaxation expectancies and less negative explicit expectancies than non-users. The frequency of use and related problems were positively associated with the explicit expectancies regarding relaxation and enhancement, and were negatively associated with negative explicit expectancies and negative implicit expectancies. Findings indicate that implicit and explicit expectancies play different roles in cannabis use by adolescents. The implications for experimentation and prevention are discussed.

  12. Dissociation between implicit and explicit expectancies of cannabis use in adolescence.

    PubMed

    Schmits, Emilie; Maurage, Pierre; Thirion, Romain; Quertemont, Etienne

    2015-12-30

    Cannabis is one of the most commonly drugs used by teenagers. Expectancies about its effects play a crucial role in cannabis consumption. Various tools have been used to assess expectancies, mainly self-report questionnaires measuring explicit expectancies, but implicit measures based on experimental tasks have also been developed, measuring implicit expectancies. The aim of this study was to simultaneously assess implicit/explicit expectancies related to cannabis among adolescent users and non-users. 130 teenagers attending school (55 girls) were enrolled (Age: M=16.40 years); 43.84% had never used cannabis ("non-users") and 56.16% had used cannabis ("users"). They completed self-report questionnaires evaluating cannabis use, cannabis-related problems, effect expectancies (explicit expectancies), alcohol use, social and trait anxiety, depression, as well as three Implicit Association Tests (IAT) assessing implicit expectancies. Adolescents manifested more implicit affective associations (relaxation, excitation, negative) than neutral ones regarding cannabis. These were not related to explicit expectancies. Cannabis users reported more implicit relaxation expectancies and less negative explicit expectancies than non-users. The frequency of use and related problems were positively associated with the explicit expectancies regarding relaxation and enhancement, and were negatively associated with negative explicit expectancies and negative implicit expectancies. Findings indicate that implicit and explicit expectancies play different roles in cannabis use by adolescents. The implications for experimentation and prevention are discussed. PMID:26575651

  13. Prospective Assessment of Cannabis Withdrawal in Adolescents with Cannabis Dependence: A Pilot Study

    ERIC Educational Resources Information Center

    Milin, Robert; Manion, Ian; Dare, Glenda; Walker, Selena

    2008-01-01

    A study to identify and assess the withdrawal symptoms in adolescents afflicted with cannabis dependence is conducted. Results conclude that withdrawal symptoms of cannabis were present in adolescents seeking treatment for this substance abuse.

  14. Motivational and control mechanisms underlying adolescent cannabis use disorders: A prospective study.

    PubMed

    Cousijn, Janna; van Benthem, Patty; van der Schee, Evelien; Spijkerman, Renske

    2015-12-01

    Cannabis use disorders (CUDs) are the most prevalent substance use disorders among adolescents in treatment. Yet, little is known about the neuropsychological mechanisms underlying adolescent CUDs. Studies in adult cannabis users suggest a significant role for cognitive control and cannabis-oriented motivational processes, such as attentional bias, approach bias, and craving in CUDs. The current 6-month prospective study investigated the relationships between attentional bias, approach bias, craving, cognitive control, and cannabis use in adolescent patients in treatment for a primary or secondary CUD. Moreover, we investigated if these motivational processes and cognitive control could predict treatment progression after 6 months. Adolescents with a CUD had an attentional but no approach bias towards cannabis. In contrast to adult findings on the role of attentional bias, approach bias and cognitive control, only cannabis craving significantly correlated with current cannabis use and predicted cannabis use-related problems and abstinence from cannabis 6 months later. These findings identify craving as a predictor of treatment outcome, thereby supporting an important role for craving in the course of adolescent cannabis use and dependence. This prospective study is among the first to investigate neuropsychological mechanisms underlying adolescent CUDs, warranting future longitudinal studies.

  15. Cannabis consumption initiation among adolescents: a longitudinal study.

    PubMed

    Pérez, Anna; Ariza, Carles; Sánchez-Martínez, Francesca; Nebot, Manel

    2010-02-01

    This study aimed to investigate factors related to initiation of cannabis consumption among adolescents. A questionnaire was administered to 2043 14-15-year-olds from Barcelona who were followed-up and re-interviewed after 15 months. A bivariate analysis was performed to identify the factors associated with consumption, and multivariate logistic regression was carried out to model cannabis initiation. Among matched students, 23.7% of non-users at baseline had started to consume 15 months later (23.0% boys and 24.2% girls). Among those who had reported occasional cannabis use, 30.3% reported consumption during the previous month at the follow-up survey. Factors associated with cannabis initiation among boys and girls were smoking, risky alcohol use and intention to consume cannabis. Among boys, other associated factors were frequenting bars or discotheques and not having organized activities in leisure time. Among girls, another risk factor for initiation was having cannabis-using friends. Cannabis initiation was facilitated by legal drug use, favorable attitudes and context-related variables. These results highlight the role of behavioral and contextual variables and support the importance of reinforcing social skills in preventive programs.

  16. The brain effects of cannabis in healthy adolescents and in adolescents with schizophrenia: a systematic review.

    PubMed

    James, Anthony; James, Christine; Thwaites, Thomas

    2013-12-30

    Cannabis is widely used in adolescence; however, the effects of cannabis on the developing brain remain unclear. Cannabis might be expected to have increased effects upon brain development and cognition during adolescence. There is extensive re-organisation of grey (GM) and white matter (WM) at this time, while the endocannabinoid (eCB) system, which is involved in the normal physiological regulation of neural transmission, is still developing. In healthy adolescent cannabis users there is a suggestion of greater memory loss and hippocampal volume changes. Functional studies point to recruitment of greater brain areas under cognitive load. Structural and DTI studies are few, and limited by comorbid drug and alcohol use. The studies of cannabis use in adolescent-onset schizophrenia (AOS) differ, with one study pointing to extensive GM and WM changes. There is an intriguing suggestion that the left parietal lobe may be more vulnerable to the effects of cannabis in AOS. As in adult schizophrenia cognition does not appear to be adversely affected in AOS following cannabis use. Given the limited number of studies it is not possible to draw firm conclusions. There is a need for adequately powered, longitudinal studies.

  17. Gender Differences in the Correlates of Adolescents' Cannabis Use

    PubMed Central

    Tu, Andrew W.; Ratner, Pamela A.; Johnson, Joy L.

    2008-01-01

    Adolescents' gender-specific cannabis use rates and their correlates were examined. Data were obtained via a cross-sectional survey conducted in 2004 in British Columbia, Canada, funded by the Canadian Institutes of Health Research. School districts were invited to participate, and schools within consenting districts were recruited. In total, 8,225 students (50% male)from Grades 7 to 12 participated. About 73% were “White” and 47% had used cannabis in their lifetime. Cannabis users were grouped according to their frequency of use: “never users” “frequent users” or “heavy users” Male heavy cannabis users (14.3% of boys) were more likely to be in Grade 9 or higher; be Aboriginal; report poorer economic status; never feel like an outsider; frequently use alcohol and tobacco; and have lower satisfaction with family, friends, and school compared with boys that never used. Female heavy users (8.7% of girls) were more likely to be in a higher grade; report poorer economic status, mental health, and academic performance; frequently use alcohol and tobacco; and have lower satisfaction with their school compared with female never users. Three important gender differences in the multivariate analysis of the correlates of cannabis use were noted: school grade (for boys only), Aboriginal status (for boys only), and mental health (for girls only). Despite the limitations of relying on self-reports, a subset of youth appears to be at risk for excessive cannabis use that may impair life opportunities and health. The gender differences may be important in the design and implementation of prevention or treatment programs for adolescents. PMID:18696378

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

    PubMed

    Wu, Li-Tzy; Swartz, Marvin S; Brady, Kathleen T; Hoyle, Rick H

    2015-05-01

    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. PMID:25795093

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

    PubMed

    Wu, Li-Tzy; Swartz, Marvin S; Brady, Kathleen T; Hoyle, Rick H

    2015-05-01

    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.

  20. [Cannabis and adolescence - drug misuse and development].

    PubMed

    Berthel, T

    2007-02-01

    In the last decades the consumption of Cannabis increased strongly. Parents and teachers are disconcerted. Instruments, to successfully offer assistance, are missing to many physicians and therapists. We need sufficient knowledge of the substance, the effects, side effects and possible damages, so that treatment can be successful. At the same time we have to identify the development phase of adolescence, in which the consumption takes place. Thereby it is particularly important to question, whether the consumption of Cannabis initiates psychoses, the development of addiction is possible or mental and physical development is disturbed. In this article the problem of the consumption of Cannabis in the phases of adolescence will be represented according to the challenges of adolescent people. Further more some intervention approaches, which were successful, will be presented.

  1. Mental health symptoms and their relationship to cannabis use in adolescents attending residential treatment.

    PubMed

    Albertella, Lucy; Norberg, Melissa M

    2012-01-01

    The present study examined mental health symptoms and their relationship to cannabis use and treatment outcomes in a sample of adolescents who received treatment for cannabis dependence through a residential substance use program. The sample included 132 adolescents who nominated cannabis as their primary drug of concern upon admission and who completed at least 30 days of treatment. This study found that mental health symptoms of young cannabis users reduced significantly from admission to three-month follow-up. Further, pretreatment symptoms of anxiety were associated with greater pretreatment cannabis use, while symptoms of phobic anxiety were associated with less pretreatment cannabis use. Pretreatment obsessive-compulsive and somatization symptoms were associated with greater follow-up cannabis use, whereas pretreatment paranoid ideation symptoms were associated with less follow-up cannabis use. Further, follow-up somatization, obsessive-compulsive symptoms, hostility, and phobic anxiety were associated with greater follow-up cannabis use while follow-up symptoms of interpersonal sensitivity were associated with less follow-up cannabis use. These findings highlight a variety of areas for further investigation in order to enhance current treatment for cannabis use. PMID:23457889

  2. Responsible and controlled use: Older cannabis users and harm reduction

    PubMed Central

    Lau, Nicholas; Sales, Paloma; Averill, Sheigla; Murphy, Fiona; Sato, Sye-Ok; Murphy, Sheigla

    2015-01-01

    Background Cannabis use is becoming more accepted in mainstream society. In this paper, we use Zinberg’s classic theoretical framework of drug, set, and setting to elucidate how older adult cannabis users managed health, social and legal risks in a context of normalized cannabis use. Methods We present selected findings from our qualitative study of Baby Boomer (born 1946–1964) cannabis users in the San Francisco Bay Area. Data collection consisted of a recorded, in-depth life history interview followed by a questionnaire and health survey. Qualitative interviews were analyzed to discover the factors of cannabis harm reduction from the users’ perspectives. Results Interviewees made harm reduction choices based on preferred cannabis derivatives and routes of administration, as well as why, when, where, and with whom to use. Most interviewees minimized cannabis-related harms so they could maintain social functioning in their everyday lives. Responsible and controlled use was described as moderation of quantity and frequency of cannabis used, using in appropriate settings, and respect for non-users. Users contributed to the normalization of cannabis use through normification. Conclusion Participants followed rituals or cultural practices, characterized by sanctions that helped define “normal” or “acceptable” cannabis use. Users contributed to cannabis normalization through their harm reduction methods. These cultural practices may prove to be more effective than formal legal prohibitions in reducing cannabis-related harms. Findings also suggest that users with access to a regulated market (medical cannabis dispensaries) were better equipped to practice harm reduction. More research is needed on both cannabis culture and alternative routes of administration as harm reduction methods. PMID:25911027

  3. Perceived Cannabis Use Norms and Cannabis Use among Adolescents in the United States

    PubMed Central

    Wu, Li-Tzy; Swartz, Marvin S.; Brady, Kathleen T.; Hoyle, Rick H.

    2015-01-01

    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. PMID:25795093

  4. Effects of cannabis on the adolescent brain.

    PubMed

    Jacobus, Joanna; Tapert, Susan F

    2014-01-01

    This article reviews neuroimaging, neurocognitive, and preclinical findings on the effects of cannabis on the adolescent brain. Marijuana is the second most widely used intoxicant in adolescence, and teens who engage in heavy marijuana use often show disadvantages in neurocognitive performance, macrostructural and microstructural brain development, and alterations in brain functioning. It remains unclear whether such disadvantages reflect pre-existing differences that lead to increased substances use and further changes in brain architecture and behavioral outcomes. Future work should focus on prospective investigations to help disentangle dose-dependent effects from pre-existing effects, and to better understand the interactive relationships with other commonly abused substances (e.g., alcohol) to better understand the role of regular cannabis use on neurodevelopmental trajectories.

  5. Medial temporal structures and memory functions in adolescents with heavy cannabis use

    PubMed Central

    Ashtari, Manzar; Avants, Brian; Cyckowski, Laura; Cervellione, Kelly L.; Roofeh, David; Cook, Philip; Gee, James; Sevy, Serge; Kumra, Sanjiv

    2011-01-01

    Converging lines of evidence suggest an adverse effect of heavy cannabis use on adolescent brain development, particularly on the hippocampus. In this preliminary study, we compared hippocampal morphology in 14 “treatment-seeking” adolescents (aged 18-20) with a history of prior heavy-cannabis use (5.8 joints/day) after an average of 6.7 months of drug abstinence, and 14 demographically matched normal controls. Participants underwent a high-resolution 3D MRI as well as cognitive testing including the California Verbal Learning Test (CVLT). Heavy-cannabis users showed significantly smaller volumes of the right (p< .04) and left (p< .02) hippocampus, but no significant differences in the amygdala region compared to controls. In controls, larger hippocampus volumes were observed to be significantly correlated with higher CVLT verbal learning and memory scores, but these relationships were not observed in cannabis users. In cannabis users, a smaller right hippocampus volume was correlated with a higher amount of cannabis use (r= - .57, p< .03). These data support a hypothesis that heavy-cannabis use may have an adverse effect on hippocampus development. These findings, after an average 6.7 month of supervised abstinence, lend support to a theory that cannabis use may impart long-term structural and functional damage. Alternatively, the observed hippocampal volumetric abnormalities may represent a risk factor for cannabis dependence. These data have potential significance for understanding the observed relationship between early cannabis exposure during adolescence and subsequent development of adult psychopathology reported in the literature for schizophrenia and related psychotic disorders. PMID:21296361

  6. Decreased respiratory symptoms in cannabis users who vaporize

    PubMed Central

    Earleywine, Mitch; Barnwell, Sara Smucker

    2007-01-01

    Cannabis smoking can create respiratory problems. Vaporizers heat cannabis to release active cannabinoids, but remain cool enough to avoid the smoke and toxins associated with combustion. Vaporized cannabis should create fewer respiratory symptoms than smoked cannabis. We examined self-reported respiratory symptoms in participants who ranged in cigarette and cannabis use. Data from a large Internet sample revealed that the use of a vaporizer predicted fewer respiratory symptoms even when age, sex, cigarette smoking, and amount of cannabis used were taken into account. Age, sex, cigarettes, and amount of cannabis also had significant effects. The number of cigarettes smoked and amount of cannabis used interacted to create worse respiratory problems. A significant interaction revealed that the impact of a vaporizer was larger as the amount of cannabis used increased. These data suggest that the safety of cannabis can increase with the use of a vaporizer. Regular users of joints, blunts, pipes, and water pipes might decrease respiratory symptoms by switching to a vaporizer PMID:17437626

  7. [Adolescent cannabis consumption and schizophrenia: epidemiological and experimental evidences].

    PubMed

    Parolaro, Daniela

    2010-01-01

    Marijuana is consistently the most widely used illicit drug among teenagers and most users first experiment it in adolescence. Adolescence is a critical period between childhood and adulthood, including not only reproductive maturation, but also cognitive, emotional and social maturation. In this period adolescent brain is still in transition differing anatomically and neurochemically from the adult's one. The endocannabinoid system is an important determinant for cerebral maturation, therefore its strong stimulation by the delta-9- tetrahydrocannabinol, that acts through the endocannabinoid system, might lead to subtle but lasting neurobiological changes that can affect adult brain functions and behaviour. We summarize the more recent researches investigating the relationships between adolescent exposure to cannabinoids and increased risk for psychotic disease such as schizophrenia, as highlighted by both human and animal studies. Epidemiological evidence suggests that cannabis use is a risk factor for schizophrenia, and an exacerbation of symptoms and worsening of the schizophrenic prognosis may occur in individuals with a predisposition for schizophrenia. The characteristic of adolescent brain probably makes it more vulnerable to cannabis effect producing psychotic like symptoms and possibly cause schizophrenia.

  8. The Co-Use of Tobacco and Cannabis among Adolescents over a 30-Year Period

    ERIC Educational Resources Information Center

    Webster, Lauren; Chaiton, Michael; Kirst, Maritt

    2014-01-01

    Background: This study explores the patterns of use and co-use of tobacco and cannabis among Ontario adolescents over 3 decades and if characteristics of co-users and single substance users have changed. Methods: Co-use trends for 1981-2011 were analyzed using the Centre for Addiction and Mental Health Ontario Student Drug Use and Health Survey,…

  9. Cannabis Problem Experiences Among Users of the Tobacco-Cannabis Combination Known As Blunts

    PubMed Central

    Fairman, Brian J.

    2015-01-01

    Background In most of the world, cannabis smokers mix loose tobacco inside a joint, pipe, spliff, or cone. More recently, a ‘blunt’ formulation combines these two drugs by inserting cannabis into a hollowed-out cigar. Epidemiological research linking simultaneous use of these two drugs and the development of cannabis use disorders (CUD) remains unclear. This study estimates associations linking blunt smoking with levels and subtypes of cannabis problems. Methods Cross-sectional data on 27,767 past-year cannabis users were analyzed from the US National Survey on Drug Use and Health (NSDUH) conducted from 2009–2012. Ten self-reported items of DSM-IV CUD features elicited a single latent trait of cannabis problem (CP) severity, which was then regressed on past-year blunt smoking and past-month blunt frequency measures within the context of a conceptual model. Differential item functioning (DIF) analysis evaluated potential bias in CP feature response by blunt smoking history. Results Past-year blunt smoking was associated with higher CP severity compared to cannabis users who did not smoke blunts. Days of blunt smoking in the past month also predicted higher CP severity than less frequent blunt use. Those smoking blunts experienced more subjectively felt tolerance and having spent more time obtaining or using cannabis, but were less likely to experience other problems, even at the same level of CP severity. Conclusions These findings suggest smoking blunts might promote the development of problematic cannabis use. Responses to cannabis problems differed by history of blunt smoking, possibly implicating an influence of tobacco on measurement of cannabis use disorders. PMID:25746234

  10. Neuropsychological Sex Differences Associated with Age of Initiated Use Among Young Adult Cannabis Users

    PubMed Central

    Crane, Natania A.; Schuster, Randi Melissa; Mermelstein, Robin J.; Gonzalez, Raul

    2015-01-01

    Introduction Earlier initiation of cannabis use is associated with poorer neuropsychological functioning across several domains. Given well-documented sex differences in neuromaturation during adolescence, initiation of cannabis use during this time may affect neuropsychological functioning differently for males and females. Method In the current study, we examined sex differences in the relationship between age of initiated cannabis use and neuropsychological performance after controlling for amount of lifetime cannabis use in 44 male and 25 female young adult cannabis users. Results We found that an earlier age of initiated use was related to poorer episodic memory, especially immediate recall, in females, but not in males. On the other hand, we found that, surprisingly, an earlier age of initiated use was associated with better decision-making overall. However, exploratory analyses found sex-specific factors associated with decision-making and age of initiated use, specifically that ADHD symptoms in females may drive the relationship between an earlier age of initiated use and better decision-making. Further, an earlier age of initiated use was associated with less education, a lower IQ, and fewer years of mother’s education for females, but more lifetime cannabis use for males. Conclusions Taken together, our findings suggest there are sex-differences in the associations between age of initiated cannabis use and neuropsychological functioning. The current study provides preliminary evidence that males and females may have different neuropsychological vulnerabilities that place them at risk for initiating cannabis use and continued cannabis use, highlighting the importance of examining the impact of cannabis on neuropsychological functioning separately for males and females. PMID:25832823

  11. Cannabis Liberalization and Adolescent Cannabis Use: A Cross-National Study in 38 Countries

    PubMed Central

    Shi, Yuyan; Lenzi, Michela; An, Ruopeng

    2015-01-01

    Aims To assess the associations between types of cannabis control policies at country level and prevalence of adolescent cannabis use. Setting, Participants and Design Multilevel logistic regressions were performed on 172,894 adolescents 15 year of age who participated in the 2001/2002, 2005/2006, or 2009/2010 cross-sectional Health Behaviour in School-Aged Children (HBSC) survey in 38 European and North American countries. Measures Self-reported cannabis use status was classified into ever use in life time, use in past year, and regular use. Country-level cannabis control policies were categorized into a dichotomous measure (whether or not liberalized) as well as 4 detailed types (full prohibition, depenalization, decriminalization, and partial prohibition). Control variables included individual-level sociodemographic characteristics and country-level economic characteristics. Findings Considerable intra-class correlations (.15-.19) were found at country level. With respect to the dichotomized cannabis control policy, adolescents were more likely to ever use cannabis (odds ratio (OR) = 1.10, p = .001), use in past year (OR = 1.09, p = .007), and use regularly (OR = 1.26, p = .004). Although boys were substantially more likely to use cannabis, the correlation between cannabis liberalization and cannabis use was smaller in boys than in girls. With respect to detailed types of policies, depenalization was associated with higher odds of past-year use (OR = 1.14, p = .013) and regular use (OR = 1.23, p = .038), and partial prohibition was associated with higher odds of regular use (OR = 2.39, p = .016). The correlation between cannabis liberalization and regular use was only significant after the policy had been introduced for more than 5 years. Conclusions Cannabis liberalization with depenalization and partial prohibition policies was associated with higher levels of regular cannabis use among adolescents. The correlations were heterogeneous between genders and

  12. Cannabis users differ from non-users on measures of personality and schizotypy.

    PubMed

    Fridberg, Daniel J; Vollmer, Jennifer M; O'Donnell, Brian F; Skosnik, Patrick D

    2011-03-30

    Accumulating evidence indicates that cannabis use may be a risk factor for schizophrenia (SZ), and chronic cannabis users score higher than non-users on measures of schizotypal personality traits. The purpose of the present study was to investigate the relations between normal personality, schizotypy, and cannabis use. Sixty-two chronic cannabis users and 45 cannabis-naïve controls completed a measure of normal personality, the NEO-Five Factor Inventory (NEO-FFI), and two measures of schizotypy, the schizotypal personality questionnaire (SPQ) and perceptual aberration scale (PAS). Substance use was assessed using the SCID I alcohol/drug module and a locally developed drug use questionnaire. On the NEO-FFI, users scored higher than controls on openness, but lower on agreeableness and conscientiousness, and endorsed greater schizotypy on the SPQ and PAS. Higher neuroticism predicted greater schizotypy in both groups, and, higher Extraversion predicted lower negative-syndrome schizotypy among users. Finally, duration of cannabis use was positively correlated with scores on the SPQ and PAS among users, suggesting a relation between overall cannabis use chronicity and schizotypy. These data show that cannabis users differ from non-users on dimensions of normal personality and schizotypy, and provide further evidence that cannabis use is associated with increased levels of psychosis-related personality traits.

  13. [Cannabis use among children and adolescents: impacts and consequences].

    PubMed

    Peyret, Emmanuelle; Delorme, Richard

    2014-03-01

    A health policy for the prevention and treatment of cannabis-related disorders is urgently needed in France, given the high prevalence of cannabis use among children and adolescents. Such a policy will require a better understanding of the endo-cannabinoid system and the impact of exogenous cannabinoids in this fragile population. The brain continues to undergo significant development until the age of about 25 years, and cannabis consumption by young people therefore carries specific risks of dependence (frequency and intensity), and of neuroanatomical, cognitive and emotional damage. This article summarizes the available data and offers a medical view of the risks and consequences of cannabis use by children and adolescents.

  14. When Cannabis Is Available and Visible at School--A Multilevel Analysis of Students' Cannabis Use

    ERIC Educational Resources Information Center

    Kuntsche, Emmanuel

    2010-01-01

    Aims: To investigate the links between the visibility of cannabis use in school (measured by teachers' reports of students being under the influence of cannabis on school premises), the proportion of cannabis users in the class, perceived availability of cannabis, as well as adolescent cannabis use. Methods: A multilevel regression model was…

  15. Psychotic experiences are linked to cannabis use in adolescents in the community because of common underlying environmental risk factors.

    PubMed

    Shakoor, Sania; Zavos, Helena M S; McGuire, Philip; Cardno, Alastair G; Freeman, Daniel; Ronald, Angelica

    2015-06-30

    Cannabis users are more likely to have psychotic experiences (PEs). The degree to which these associations are driven by genetic or environmental influences in adolescence is unknown. This study estimated the genetic and environmental contributions to the relationship between cannabis use and PEs. Specific PEs were measured in a community-based twin sample (4830 16-year-old pairs) using self-reports and parent-reports. Adolescents reported on ever using cannabis. Multivariate liability threshold structural equation model-fitting was conducted. Cannabis use was significantly correlated with PEs. Modest heritability (37%), common environmental influences (55%) and unique environment (8%) were found for cannabis use. For PEs, modest heritability (27-54%), unique environmental influences (E=12-50%) and little common environmental influences (11-20%), with the exception of parent-rated Negative Symptoms (42%), were reported. Environmental influences explained all of the covariation between cannabis use and paranoia, cognitive disorganization and parent-rated negative symptoms (bivariate common environment=69-100%, bivariate unique environment=28-31%), whilst the relationship between cannabis use and hallucinations indicated familial influences. Cannabis use explains 2-5% of variance in positive, cognitive, and negative PEs. Cannabis use and psychotic experience co-occur due to environmental factors. Focus on specific environments may reveal why adolescent cannabis use and psychotic experiences tend to 'travel together'.

  16. Cannabis receptor haplotype associated with fewer cannabis dependence symptoms in adolescents.

    PubMed

    Hopfer, Christian J; Young, Susan E; Purcell, Shaun; Crowley, Thomas J; Stallings, Michael C; Corley, Robin P; Rhee, Soo Hyun; Smolen, Andrew; Krauter, Ken; Hewitt, John K; Ehringer, Marissa A

    2006-12-01

    Cannabis is a major substance of abuse, and the gene encoding for the central cannabinoid receptor (CNR1) is a logical candidate gene for vulnerability toward developing symptoms of cannabis dependence. We studied four single-nucleotide polymorphisms (SNPs) in the CNR1 gene for association with having one or more symptoms of cannabis dependence in 541 adolescent subjects who had all tried cannabis five or more times. Cases (327) were defined as those who had tried marijuana and developed one or more symptoms, and controls (214) as those who had tried marijuana but developed no dependence symptoms. Cannabis dependence symptoms were assessed in these youth when they were 17 or older with the Composite International Diagnostic Interview--Substance Abuse Module. Univariate (single-marker) association tests demonstrated that SNP rs806380, located in intron 2 of the CNR1 gene, was significantly associated with developing one or more cannabis dependence symptoms, with the G allele having a protective effect (P < 0.02). This was consistent with the results of the global haplotype test (P < 0.01). One of the common haplotypes examined (present in 21% of the subjects) was significantly associated with a lower rate of having one or more cannabis dependence symptoms. Our findings provide evidence suggesting that a common CNR1 haplotype is associated with developing fewer cannabis dependence symptoms among adolescents who have experimented with cannabis.

  17. Rat models of prenatal and adolescent cannabis exposure.

    PubMed

    Dinieri, Jennifer A; Hurd, Yasmin L

    2012-01-01

    Marijuana (Cannabis sativa) is the illicit drug most commonly used by two vulnerable populations relevant to neurodevelopment-pregnant women and teenagers. Human longitudinal studies have linked prenatal and adolescent cannabis exposure with long-term behavioral abnormalities as well as increased vulnerability to neuropsychiatric disorders in adulthood. Animal models provide a means of studying the neurobiological mechanisms underlying these long-term effects. This chapter provides an overview of the animal models we have used to study the developmental impact of cannabis.

  18. The Role of Cannabinoids in Neuroanatomic Alterations in Cannabis Users.

    PubMed

    Lorenzetti, Valentina; Solowij, Nadia; Yücel, Murat

    2016-04-01

    The past few decades have seen a marked change in the composition of commonly smoked cannabis. These changes primarily involve an increase of the psychoactive compound ∆(9)-tetrahydrocannabinol (THC) and a decrease of the potentially therapeutic compound cannabidiol (CBD). This altered composition of cannabis may be linked to persistent neuroanatomic alterations typically seen in regular cannabis users. In this review, we summarize recent findings from human structural neuroimaging investigations. We examine whether neuroanatomic alterations are 1) consistently observed in samples of regular cannabis users, particularly in cannabinoid receptor-high areas, which are vulnerable to the effects of high circulating levels of THC, and 2) associated either with greater levels of cannabis use (e.g., higher dosage, longer duration, and earlier age of onset) or with distinct cannabinoid compounds (i.e., THC and CBD). Across the 31 studies selected for inclusion in this review, neuroanatomic alterations emerged across regions that are high in cannabinoid receptors (i.e., hippocampus, prefrontal cortex, amygdala, cerebellum). Greater dose and earlier age of onset were associated with these alterations. Preliminary evidence shows that THC exacerbates, whereas CBD protects from, such harmful effects. Methodologic differences in the quantification of levels of cannabis use prevent accurate assessment of cannabis exposure and direct comparison of findings across studies. Consequently, the field lacks large "consortium-style" data sets that can be used to develop reliable neurobiological models of cannabis-related harm, recovery, and protection. To move the field forward, we encourage a coordinated approach and suggest the urgent development of consensus-based guidelines to accurately and comprehensively quantify cannabis use and exposure in human studies. PMID:26858212

  19. Cue reactivity in cannabis-dependent adolescents.

    PubMed

    Nickerson, Lisa D; Ravichandran, Caitlin; Lundahl, Leslie H; Rodolico, John; Dunlap, Steven; Trksak, George H; Lukas, Scott E

    2011-03-01

    The authors measured event-related potentials with a craving manipulation to investigate the neural correlates of drug cue reactivity in 13 adolescents who are cannabis dependent (CD; ages 14-17). The P300 responses to marijuana (MJ) pictures (MJ-P300) and control pictures (C-P300) were assessed after handling neutral objects and again after handling MJ paraphernalia (MJP). Self-reported drug craving and heart rates also were measured. MJ-P300 were larger than C-P300 (p < .001), and both the MJ-P300 and craving increased significantly after handling MJP (p = .002 and p = .003, respectively), with no association between the magnitude of craving and MJ-P300. Heart rates were not affected by handling MJP. The results showed that adolescents who are CD have an attentional bias to MJ stimuli that increases after handling marijuana paraphernalia. Generally, the results are consistent with what has been reported for adult heavy chronic cannabis smokers, although there were some differences that require further investigation. PMID:21142334

  20. Sex differences in cannabis withdrawal symptoms among treatment-seeking cannabis users.

    PubMed

    Herrmann, Evan S; Weerts, Elise M; Vandrey, Ryan

    2015-12-01

    Over 300,000 individuals enter treatment for cannabis-use disorders (CUDs) in the United States annually. Cannabis withdrawal is associated with poor CUD-treatment outcomes, but no prior studies have examined sex differences in withdrawal among treatment-seeking cannabis users. Treatment-seeking cannabis users (45 women and 91 men) completed a Marijuana Withdrawal Checklist (Budney, Novy, & Hughes, 1999, Budney, Moore, Vandrey, & Hughes, 2003) at treatment intake to retrospectively characterize withdrawal symptoms experienced during their most recent quit attempt. Scores from the 14-item Composite Withdrawal Discomfort Scale (WDS), a subset of the Marijuana Withdrawal Checklist that corresponds to valid cannabis withdrawal symptoms described in the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; APA, 2013) were calculated. Demographic and substance-use characteristics, overall WDS scores, and scores on individual WDS symptoms were compared between women and men. Women had higher overall WDS scores than men, and women had higher scores than men on 6 individual symptoms in 2 domains, mood symptoms (i.e., irritability, restlessness, increased anger, violent outbursts), and gastrointestinal symptoms (i.e., nausea, stomach pain). Follow-up analyses isolating the incidence and severity of WDS symptoms demonstrated that women generally reported a higher number of individual withdrawal symptoms than men, and that they reported experiencing some symptoms as more severe. This is the first report to demonstrate that women seeking treatment for CUDs may experience more withdrawal then men during quit attempts. Prospective studies of sex differences in cannabis withdrawal are warranted.

  1. Approach-bias predicts development of cannabis problem severity in heavy cannabis users: results from a prospective FMRI study.

    PubMed

    Cousijn, Janna; Goudriaan, Anna E; Ridderinkhof, K Richard; van den Brink, Wim; Veltman, Dick J; Wiers, Reinout W

    2012-01-01

    A potentially powerful predictor for the course of drug (ab)use is the approach-bias, that is, the pre-reflective tendency to approach rather than avoid drug-related stimuli. Here we investigated the neural underpinnings of cannabis approach and avoidance tendencies. By elucidating the predictive power of neural approach-bias activations for future cannabis use and problem severity, we aimed at identifying new intervention targets. Using functional Magnetic Resonance Imaging (fMRI), neural approach-bias activations were measured with a Stimulus Response Compatibility task (SRC) and compared between 33 heavy cannabis users and 36 matched controls. In addition, associations were examined between approach-bias activations and cannabis use and problem severity at baseline and at six-month follow-up. Approach-bias activations did not differ between heavy cannabis users and controls. However, within the group of heavy cannabis users, a positive relation was observed between total lifetime cannabis use and approach-bias activations in various fronto-limbic areas. Moreover, approach-bias activations in the dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC) independently predicted cannabis problem severity after six months over and beyond session-induced subjective measures of craving. Higher DLPFC/ACC activity during cannabis approach trials, but lower activity during cannabis avoidance trials were associated with decreases in cannabis problem severity. These findings suggest that cannabis users with deficient control over cannabis action tendencies are more likely to develop cannabis related problems. Moreover, the balance between cannabis approach and avoidance responses in the DLPFC and ACC may help identify individuals at-risk for cannabis use disorders and may be new targets for prevention and treatment.

  2. A comparison of delay discounting in adolescents and adults in treatment for cannabis use disorders.

    PubMed

    Lee, Dustin C; Stanger, Catherine; Budney, Alan J

    2015-04-01

    Delay discounting is associated with problematic substance use and poorer treatment outcomes in adolescents and adults with substance use disorders. Although some research has addressed delay discounting among individuals with cannabis use disorders (CUDs), results have been equivocal, and no study has examined whether discounting rates differ between adolescent and adult cannabis users. The aim of this study was to compare discounting rates between adolescents and adults in treatment for CUD to determine whether discounting at intake or changes in discounting across treatment differed between age groups. Participants were 165 adolescents and 104 adults enrolled in treatment for CUD. Participants completed a delay discounting task at intake and end of treatment for 2 commodities (money and cannabis) at 2 different magnitudes ($100 and $1,000). Repeated measures mixed models examined differences in discounting rates by commodity and magnitude across age groups at intake and changes in discounting across treatment. At intake, adolescents discounted money more than adults whereas adults showed greater discounting at $100 magnitude than $1,000. In addition, adults had greater decreases in discounting of cannabis over the course of treatment. Overall, adolescents appeared less sensitive to changes in magnitude of rewards, discounted money at higher rates, and showed less improvement in discounting over the course of treatment compared to adults. Comparing delay discounting in adolescents and adults with CUD can contribute to a better understanding of how development influences the effect of discounting on substance use to better inform treatment for substance use disorders.

  3. Cannabis use in early adolescence: Evidence of amygdala hypersensitivity to signals of threat.

    PubMed

    Spechler, Philip A; Orr, Catherine A; Chaarani, Bader; Kan, Kees-Jan; Mackey, Scott; Morton, Aaron; Snowe, Mitchell P; Hudson, Kelsey E; Althoff, Robert R; Higgins, Stephen T; Cattrell, Anna; Flor, Herta; Nees, Frauke; Banaschewski, Tobias; Bokde, Arun L W; Whelan, Robert; Büchel, Christian; Bromberg, Uli; Conrod, Patricia; Frouin, Vincent; Papadopoulos, Dimitri; Gallinat, Jurgen; Heinz, Andreas; Walter, Henrik; Ittermann, Bernd; Gowland, Penny; Paus, Tomáš; Poustka, Luise; Martinot, Jean-Luc; Artiges, Eric; Smolka, Michael N; Schumann, Gunter; Garavan, Hugh

    2015-12-01

    Cannabis use in adolescence may be characterized by differences in the neural basis of affective processing. In this study, we used an fMRI affective face processing task to compare a large group (n=70) of 14-year olds with a history of cannabis use to a group (n=70) of never-using controls matched on numerous characteristics including IQ, SES, alcohol and cigarette use. The task contained short movies displaying angry and neutral faces. Results indicated that cannabis users had greater reactivity in the bilateral amygdalae to angry faces than neutral faces, an effect that was not observed in their abstinent peers. In contrast, activity levels in the cannabis users in cortical areas including the right temporal-parietal junction and bilateral dorsolateral prefrontal cortex did not discriminate between the two face conditions, but did differ in controls. Results did not change after excluding subjects with any psychiatric symptomology. Given the high density of cannabinoid receptors in the amygdala, our findings suggest cannabis use in early adolescence is associated with hypersensitivity to signals of threat. Hypersensitivity to negative affect in adolescence may place the subject at-risk for mood disorders in adulthood. PMID:26347227

  4. Cannabis use in early adolescence: Evidence of amygdala hypersensitivity to signals of threat.

    PubMed

    Spechler, Philip A; Orr, Catherine A; Chaarani, Bader; Kan, Kees-Jan; Mackey, Scott; Morton, Aaron; Snowe, Mitchell P; Hudson, Kelsey E; Althoff, Robert R; Higgins, Stephen T; Cattrell, Anna; Flor, Herta; Nees, Frauke; Banaschewski, Tobias; Bokde, Arun L W; Whelan, Robert; Büchel, Christian; Bromberg, Uli; Conrod, Patricia; Frouin, Vincent; Papadopoulos, Dimitri; Gallinat, Jurgen; Heinz, Andreas; Walter, Henrik; Ittermann, Bernd; Gowland, Penny; Paus, Tomáš; Poustka, Luise; Martinot, Jean-Luc; Artiges, Eric; Smolka, Michael N; Schumann, Gunter; Garavan, Hugh

    2015-12-01

    Cannabis use in adolescence may be characterized by differences in the neural basis of affective processing. In this study, we used an fMRI affective face processing task to compare a large group (n=70) of 14-year olds with a history of cannabis use to a group (n=70) of never-using controls matched on numerous characteristics including IQ, SES, alcohol and cigarette use. The task contained short movies displaying angry and neutral faces. Results indicated that cannabis users had greater reactivity in the bilateral amygdalae to angry faces than neutral faces, an effect that was not observed in their abstinent peers. In contrast, activity levels in the cannabis users in cortical areas including the right temporal-parietal junction and bilateral dorsolateral prefrontal cortex did not discriminate between the two face conditions, but did differ in controls. Results did not change after excluding subjects with any psychiatric symptomology. Given the high density of cannabinoid receptors in the amygdala, our findings suggest cannabis use in early adolescence is associated with hypersensitivity to signals of threat. Hypersensitivity to negative affect in adolescence may place the subject at-risk for mood disorders in adulthood.

  5. Weeding Out the Truth: Adolescents and Cannabis.

    PubMed

    Ammerman, Seth; Tau, Gregory

    2016-01-01

    The use of cannabis for both legal (similar to alcohol) and medical purposes is becoming more common. Although cannabis remains an illegal Schedule 1 drug federally, as of November 2015, 23 states and the District of Columbia have legalized "medical" cannabis, and 4 states and the District of Columbia have legalized the use of cannabis for adults aged 21 years and older. It is very likely that more and more states will sooner rather than later allow cannabis for both medical and legal purposes. This review article will focus on a variety of issues relevant to the current debate about cannabis, and will address the following.

  6. Considering Cannabis: The Effects of Regular Cannabis Use on Neurocognition in Adolescents and Young Adults

    PubMed Central

    Lisdahl, Krista M.; Wright, Natasha E.; Kirchner-Medina, Christopher; Maple, Kristin E.; Shollenbarger, Skyler

    2014-01-01

    Thirty-six percent of high school seniors have used cannabis in the past year, and an alarming 6.5% smoked cannabis daily, up from 2.4% in 1993 (Johnston et al., 2013). Adolescents and emerging adults are undergoing significant neurodevelopment and animal studies suggest they may be particularly vulnerable to negative drug effects. In this review, we will provide a detailed overview of studies outlining the effects of regular (at least weekly) cannabis use on neurocognition, including studies outlining cognitive, structural and functional findings. We will also explore the public health impact of this research. PMID:25013751

  7. Potential protective effects of cannabidiol on neuroanatomical alterations in cannabis users and psychosis: a critical review.

    PubMed

    Hermann, Derik; Schneider, Miriam

    2012-01-01

    Cannabis use and the development of schizophrenic psychoses share a variety of similarities. Both start during late adolescence; go along with neuropsychological deficits, reduced activity, motivation deficits, and hallucinations suggesting impairment of similar brain structures. In cannabis heavy users diminished regional gray and white matter volume was reported. Similar alterations were observed in the large literature addressing structural abnormalities in schizophrenia. Furthermore, in cannabis using schizophrenic patients, these brain alterations were especially pronounced. Close relatives of schizophrenic patients showed greater cannabis-associated brain tissue loss than non-relatives indicating a genetically mediated particular sensitivity to brain tissue loss. Possible mechanisms for the induction of structural brain alterations are here discussed including impairments of neurogenesis, disturbance of endocannabinoids and diminished neuroplasticity. Especially direct THC effects (or via endocannabinoids) may mediate diminished glutamatergic neurotransmission usually driving neuroplasticity. Correspondingly, alterations of the kynurenic acid blocking NMDA receptors may contribute to brain structure alterations. However, different cannabis compounds may exert opposite effects on the neuroanatomical changes underlying psychosis. In particular, cannabidiol (CBD) was shown to prevent THC associated hippocampal volume loss in a small pilot study. This finding is further supported by several animal experiments supporting neuroprotective properties of CBD mainly via anti-oxidative effects, CB2 receptors or adenosine receptors. We will discuss here the mechanisms by which CBD may reduce brain volume loss, including antagonism of THC, interactions with endocannabinoids, and mechanisms that specifically underlie antipsychotic properties of CBD.

  8. Antecedents and Consequences of Cannabis Use among Racially Diverse Cannabis Users: An Analysis from Ecological Momentary Assessment

    PubMed Central

    Buckner, Julia D.; Zvolensky, Michael J.; Crosby, Ross D.; Wonderlich, Stephen A.; Ecker, Anthony H.; Richter, Ashley

    2015-01-01

    Background Cannabis remains the most commonly used illicit substance and use rates are rising. Notably, the prevalence of cannabis use disorders (CUD) nearly equals that of other illicit substance use disorders combined. Thus, the present study aimed to identify cognitive, affective, and situational predictors and consequences of ad-lib cannabis use in a racially diverse sample. Methods The sample consisted of 93 current cannabis users (34.4% female; 57.1% non-Hispanic Caucasian), 87.1% of whom evinced a current CUD. Ecological momentary assessment was used to collect frequent ratings of cannabis withdrawal, craving, affect, cannabis use motives, and peer cannabis use over two weeks. Mixed effects linear models examined within- and between-day correlates and consequences of cannabis use. Results Withdrawal and craving were higher on cannabis use days than non-use days. Withdrawal, craving, and positive and negative affect were higher immediately prior to cannabis use compared to non-use episodes. Withdrawal and craving were higher among those who subsequently used cannabis than those who did not. Cannabis use resulted in less subsequent withdrawal, craving, and negative affect. Enhancement and coping motives were the most common reasons cited for use. Withdrawal and negative affect were related to using cannabis for coping motives and social motives. Participants were most likely to use cannabis if others were using, and withdrawal and craving were greater in social situations when others were using. Conclusions Data support the contention that cannabis withdrawal and craving and affect and peer use play important roles in the maintenance of cannabis use. PMID:25578250

  9. Limitations in the assessment of DSM-IV cannabis tolerance as an indicator of dependence in adolescents.

    PubMed

    Chung, Tammy; Martin, Christopher S; Winters, Ken C; Cornelius, Jack R; Langenbucher, James W

    2004-05-01

    The usefulness of the Diagnostic and Statistical Manual's (4th ed.; DSM-IV; American Psychiatric Association, 1994) tolerance criterion as an indicator of dependence has been debated. The authors of this study evaluated the performance of DSM's cannabis tolerance criterion, operationally defined as a percentage increase in quantity needed to get high, in distinguishing adolescents with and without cannabis dependence. Two samples of adolescent cannabis users (ages 12-19) provided data (ns = 417 and 380). Tolerance, defined as a percentage increase (median increase = 300% and 175%, respectively, in the samples), had only moderate overall sensitivity and specificity in distinguishing those with and without cannabis dependence. Results suggest limitations of the DSM-IV and change-based operational definition of tolerance in adolescents. PMID:15122958

  10. Cannabis use and memory brain function in adolescent boys: a cross-sectional multicenter fMRI study

    PubMed Central

    Jager, Gerry; Block, Robert I.; Luijten, Maartje; Ramsey, Nick F.

    2010-01-01

    Objective Early-onset cannabis use has been associated with later (ab)use, mental health problems (psychosis, depression) and abnormal development of cognition and brain function. During adolescence ongoing neurodevelopmental maturation and experience shape the neural circuitry underlying complex cognitive functions such as memory and executive control. Prefrontal and temporal regions are critically involved in these functions. Maturational processes leave these brain areas prone to the potentially harmful effects of cannabis use. Method We performed a two-site (US and NL; pooled data) functional MRI study with a cross-sectional design, investigating the effects of adolescent cannabis use on working memory (WM) and associative memory (AM) brain function in twenty-one abstinent but frequent cannabis using boys (age 13 – 19) and compared them with twenty-four non-using peers. Brain activity during WM was assessed before and following rule-based learning (automatization). AM was assessed using a pictorial hippocampal-dependent memory task. Results Cannabis users performed normally on both memory tasks. During WM assessment cannabis users showed excessive activity in prefrontal regions when a task was novel, whereas automatization of the task reduced activity to the same level in users and controls. No effect of cannabis use on AM-related brain function was found. Conclusions In adolescent cannabis users the WM system was overactive during a novel task, suggesting functional compensation. Inefficient WM recruitment was not related to a failure in automatization, but became evident when processing continuously changing information. The results seem to confirm the vulnerability of still developing frontal lobe functioning for early-onset cannabis use. PMID:20494266

  11. [Cannabis use among children and adolescents: impacts and consequences].

    PubMed

    Peyret, Emmanuelle; Delorme, Richard

    2014-03-01

    A health policy for the prevention and treatment of cannabis-related disorders is urgently needed in France, given the high prevalence of cannabis use among children and adolescents. Such a policy will require a better understanding of the endo-cannabinoid system and the impact of exogenous cannabinoids in this fragile population. The brain continues to undergo significant development until the age of about 25 years, and cannabis consumption by young people therefore carries specific risks of dependence (frequency and intensity), and of neuroanatomical, cognitive and emotional damage. This article summarizes the available data and offers a medical view of the risks and consequences of cannabis use by children and adolescents. PMID:26427298

  12. Cannabis Use in Adolescence and Young Adulthood: A Review of Findings from the Victorian Adolescent Health Cohort Study.

    PubMed

    Coffey, Carolyn; Patton, George C

    2016-06-01

    The Victorian Adolescent Health Cohort Study (VAHCS) is a long-term Australian cohort study that has documented cannabis use in young Australians from the mid-teens to the mid-30s. The study findings have described the natural history of early cannabis use, remission, and escalation and the social and mental health consequences of different patterns of use. The adverse consequences of cannabis use are most clear-cut in heavy early adolescent users. These consequences include educational failure, persisting mental health problems, and progression to other substance use. For later onset and occasional users, the risks are lower and appear to entail modest elevations in risk for other drug use compared with never users. With growing evidence of health consequences, there is a strong case for actions around early heavy adolescent users. Prevention of early use, identification and treatment of early heavy users, and harm reduction through diversion of early heavy users away from the custodial justice system into health care are all priority responses. PMID:27254840

  13. Cannabis Use in Adolescence and Young Adulthood: A Review of Findings from the Victorian Adolescent Health Cohort Study.

    PubMed

    Coffey, Carolyn; Patton, George C

    2016-06-01

    The Victorian Adolescent Health Cohort Study (VAHCS) is a long-term Australian cohort study that has documented cannabis use in young Australians from the mid-teens to the mid-30s. The study findings have described the natural history of early cannabis use, remission, and escalation and the social and mental health consequences of different patterns of use. The adverse consequences of cannabis use are most clear-cut in heavy early adolescent users. These consequences include educational failure, persisting mental health problems, and progression to other substance use. For later onset and occasional users, the risks are lower and appear to entail modest elevations in risk for other drug use compared with never users. With growing evidence of health consequences, there is a strong case for actions around early heavy adolescent users. Prevention of early use, identification and treatment of early heavy users, and harm reduction through diversion of early heavy users away from the custodial justice system into health care are all priority responses.

  14. Adolescent ischemic stroke associated with anabolic steroid and cannabis abuse.

    PubMed

    El Scheich, Tarik; Weber, Artur-Aron; Klee, Dirk; Schweiger, Daniel; Mayatepek, Ertan; Karenfort, Michael

    2013-01-01

    We report on a 16-year-old body builder who suffered from an acute ischemic stroke. In the urine, cannabis metabolites as well as metabolites of the oral androgenic-anabolic steroid methandrostenolone were detected, both known to be associated with stroke events. This report highlights the role of cannabis and steroid abuse that induce strokes in the absence of arteriopathy, cardioembolism or thrombophilia. Owing to new upcoming socio-behavioral aspects of late childhood and early adolescent life, this formally rare abuse of cannabis and/or anabolic steroids as well as their associations with strokes becomes more current than ever. PMID:23382306

  15. Tentative evidence for striatal hyperactivity in adolescent cannabis-using boys: a cross-sectional multicenter fMRI study.

    PubMed

    Jager, Gerry; Block, Robert I; Luijten, Maartje; Ramsey, Nick F

    2013-01-01

    Adolescents' risk-taking behavior has been linked to a maturational imbalance between reward ("go") and inhibitory-control ("stop")-related brain circuitry. This may drive adolescent drug-taking, such as cannabis use. In this study, we assessed the non-acute effects of adolescent cannabis use on reward-related brain function. We performed a two-site (United States and Netherlands; pooled data) functional magnetic resonance imaging (fMRI) study with a cross-sectional design. Twenty-one abstinent but frequent cannabis-using boys were compared with 24 non-using peers on reward-related brain function, using a monetary incentive delay task with fMRI. Focus was on anticipatory and response stages of reward and brain areas critically involved in reward processing like the striatum. Performance in users was normal. Region-of-interest analysis indicated striatal hyperactivity during anticipatory stages of reward in users. Intriguingly, this effect was most pronounced during non-rewarding events. Striatal hyperactivity in adolescent cannabis users may signify an overly sensitive motivational brain circuitry. Frequent cannabis use during adolescence may induce diminished ability to disengage the motivational circuit when no reward can be obtained. This could strengthen the search for reinforcements like drugs of abuse, even when facing the negative (non-rewarding) consequences. PMID:23909003

  16. Tentative Evidence for Striatal Hyperactivity in Adolescent Cannabis Using Boys: A Cross-Sectional Multicenter fMRI Study

    PubMed Central

    Jager, Gerry; Block, Robert I.; Luijten, Maartje; Ramsey, Nick F.

    2013-01-01

    Adolescents' risk-taking behavior has been linked to a maturational imbalance between reward (“go”) and inhibitory-control (“stop”) related brain circuitry. This may drive adolescent drug-taking, such as cannabis use. In this study we assessed the non-acute effects of adolescent cannabis use on reward-related brain function. We performed a two-site (United States and Netherlands; pooled data) functional magnetic resonance imaging (fMRI) study with a cross-sectional design. Twenty-one abstinent but frequent cannabis-using boys were compared with 24 non-using peers on reward-related brain function, using a monetary incentive delay task with fMRI. Focus was on anticipatory and response stages of reward and brain areas critically involved in reward processing like the striatum. Performance in users was normal. Region-of-interest analysis indicated striatal hyperactivity during anticipatory stages of reward in users. Intriguingly, this effect was most pronounced during non-rewarding events. Striatal hyperactivity in adolescent cannabis users may signify an overly sensitive motivational brain circuitry. Frequent cannabis use during adolescence may induce diminished ability to disengage the motivational circuit when no reward can be obtained. This could strengthen the search for reinforcements like drugs of abuse, even when facing the negative (non-rewarding) consequences. PMID:23909003

  17. Tentative evidence for striatal hyperactivity in adolescent cannabis-using boys: a cross-sectional multicenter fMRI study.

    PubMed

    Jager, Gerry; Block, Robert I; Luijten, Maartje; Ramsey, Nick F

    2013-01-01

    Adolescents' risk-taking behavior has been linked to a maturational imbalance between reward ("go") and inhibitory-control ("stop")-related brain circuitry. This may drive adolescent drug-taking, such as cannabis use. In this study, we assessed the non-acute effects of adolescent cannabis use on reward-related brain function. We performed a two-site (United States and Netherlands; pooled data) functional magnetic resonance imaging (fMRI) study with a cross-sectional design. Twenty-one abstinent but frequent cannabis-using boys were compared with 24 non-using peers on reward-related brain function, using a monetary incentive delay task with fMRI. Focus was on anticipatory and response stages of reward and brain areas critically involved in reward processing like the striatum. Performance in users was normal. Region-of-interest analysis indicated striatal hyperactivity during anticipatory stages of reward in users. Intriguingly, this effect was most pronounced during non-rewarding events. Striatal hyperactivity in adolescent cannabis users may signify an overly sensitive motivational brain circuitry. Frequent cannabis use during adolescence may induce diminished ability to disengage the motivational circuit when no reward can be obtained. This could strengthen the search for reinforcements like drugs of abuse, even when facing the negative (non-rewarding) consequences.

  18. Research note: adolescents' perception of psychosis risk following cannabis consumption.

    PubMed

    Mihalca, Andreea Mihaela; Gherasim, Loredana Ruxandra; Chendran, Laura Alexandra

    2012-03-01

    Cannabis consumption during adolescence has been associated with the onset of psychosis. In 2010, we examined adolescents' perception of this association. Adolescents (N = 583) from four Romanian urban high schools filled in psychosis proneness scales according to the risk they assigned to hypothetical adolescents described in vignettes. Target adolescent's frequency and age of first consumption were manipulated. Analysis of variance indicated a main effect of target's consumption frequency, but no effect of age of first consumption on psychosis risk perception. Participants' own consumption status acted as moderator. Results highlight the discrepancy between clinical research results and adolescents' perception of psychosis risk. The study's limitations are noted.

  19. Believability of Messages about Cannabis, Cocaine and Heroin among Never-Triers, Trier-Rejecters and Current Users of Cannabis

    ERIC Educational Resources Information Center

    Jones, Sandra C.; Rossiter, John R.

    2004-01-01

    This paper examines the believability of strong warnings about the negative consequences of drug use among young adults in Australia who have never tried, currently use, or have tried and rejected cannabis. It finds that the strong warnings about cannabis are generally believed by never-triers. The same warnings are perceived by current users as…

  20. A Meta-Analysis of Interventions to Reduce Adolescent Cannabis Use

    ERIC Educational Resources Information Center

    Bender, Kimberly; Tripodi, Stephen J.; Sarteschi, Christy; Vaughn, Michael G.

    2011-01-01

    Objective: This meta-analytic review assesses the effectiveness of substance abuse interventions to reduce adolescent cannabis use. Method: A systematic search identified 15 randomized controlled evaluations of interventions to reduce adolescent cannabis use published between 1960 and 2008. The primary outcome variables, frequency of cannabis use,…

  1. The medicalisation of revolt: a sociological analysis of medical cannabis users.

    PubMed

    Pedersen, Willy; Sandberg, Sveinung

    2013-01-01

    In a qualitative study, we investigated the medical motives of 100 Norwegian cannabis users, none of whom had legal access to medical cannabis. Cannabis was used therapeutically for conditions such as multiple sclerosis, attention deficit hyperactivity disorder and rheumatism, as well as for quality of life conditions such as quality of sleep, relaxation and wellbeing. The borders between medical and recreational cannabis use were blurred. This article identifies strategies of medical cannabis users to gain social acceptance. Several respondents downplayed effects such as intoxication and euphoria. Others used the language of medicine and knowledge of current research in psychopharmacology. Cannabis was contrasted with the potential for abuse of prescription medicines. The medical cannabis movement has had little success in Norway. Medical professionals are unable to accept that users may be more knowledgeable than experts and medical users cannot discard the values of traditional cannabis culture. Calls for medical cannabis use are thus perceived as a gambit in attempts to have cannabis legalised. We argue that, despite having had little effect on health authorities, the medical cannabis movement may be having the unintended effect of medicalising cannabis use and using it as a cure for everyday problems. PMID:22827932

  2. The medicalisation of revolt: a sociological analysis of medical cannabis users.

    PubMed

    Pedersen, Willy; Sandberg, Sveinung

    2013-01-01

    In a qualitative study, we investigated the medical motives of 100 Norwegian cannabis users, none of whom had legal access to medical cannabis. Cannabis was used therapeutically for conditions such as multiple sclerosis, attention deficit hyperactivity disorder and rheumatism, as well as for quality of life conditions such as quality of sleep, relaxation and wellbeing. The borders between medical and recreational cannabis use were blurred. This article identifies strategies of medical cannabis users to gain social acceptance. Several respondents downplayed effects such as intoxication and euphoria. Others used the language of medicine and knowledge of current research in psychopharmacology. Cannabis was contrasted with the potential for abuse of prescription medicines. The medical cannabis movement has had little success in Norway. Medical professionals are unable to accept that users may be more knowledgeable than experts and medical users cannot discard the values of traditional cannabis culture. Calls for medical cannabis use are thus perceived as a gambit in attempts to have cannabis legalised. We argue that, despite having had little effect on health authorities, the medical cannabis movement may be having the unintended effect of medicalising cannabis use and using it as a cure for everyday problems.

  3. Item Response Theory Analysis of DSM-IV Cannabis Abuse and Dependence Criteria in Adolescents

    ERIC Educational Resources Information Center

    Hartman, Christie A.; Gelhorn, Heather; Crowley, Thomas J.; Sakai, Joseph T.; Stallings, Michael; Young, Susan E.; Rhee, Soo Hyun; Corley, Robin; Hewitt, John K.; Hopfer, Christian J.

    2008-01-01

    A study to examine the DSM-IV criteria for cannabis abuse and dependence among adolescents is conducted. Results conclude that abuse and dependence criteria were not found to affect the different levels of severity in cannabis use.

  4. COMT val158met and 5-HTTLPR genetic polymorphisms moderate executive control in cannabis users.

    PubMed

    Verdejo-García, Antonio; Fagundo, Ana Beatriz; Cuenca, Aida; Rodriguez, Joan; Cuyás, Elisabet; Langohr, Klaus; de Sola Llopis, Susana; Civit, Ester; Farré, Magí; Peña-Casanova, Jordi; de la Torre, Rafael

    2013-07-01

    The adverse effects of cannabis use on executive functions are still controversial, fostering the need for novel biomarkers able to unveil individual differences in the cognitive impact of cannabis consumption. Two common genetic polymorphisms have been linked to the neuroadaptive impact of Δ9-tetrahydrocannabinol (THC) exposure and to executive functions in animals: the catechol-O-methyltransferase (COMT) gene val158met polymorphism and the SLC6A4 gene 5-HTTLPR polymorphism. We aimed to test if these polymorphisms moderate the harmful effects of cannabis use on executive function in young cannabis users. We recruited 144 participants: 86 cannabis users and 58 non-drug user controls. Both groups were genotyped and matched for genetic makeup, sex, age, education, and IQ. We used a computerized neuropsychological battery to assess different aspects of executive functions: sustained attention (CANTAB Rapid Visual Information Processing Test, RVIP), working memory (N-back), monitoring/shifting (CANTAB ID/ED set shifting), planning (CANTAB Stockings of Cambridge, SOC), and decision-making (Iowa Gambling Task, IGT). We used general linear model-based analyses to test performance differences between cannabis users and controls as a function of genotypes. We found that: (i) daily cannabis use is not associated with executive function deficits; and (ii) COMT val158met and 5-HTTLPR polymorphisms moderate the link between cannabis use and executive performance. Cannabis users carrying the COMT val/val genotype exhibited lower accuracy of sustained attention, associated with a more strict response bias, than val/val non-users. Cannabis users carrying the COMT val allele also committed more monitoring/shifting errors than cannabis users carrying the met/met genotype. Finally, cannabis users carrying the 5-HTTLPR s/s genotype had worse IGT performance than s/s non-users. COMT and SLC6A4 genes moderate the impact of cannabis use on executive functions.

  5. Characteristics of Cannabis-Only and Other Drug Users Who Visit the Emergency Department

    PubMed Central

    Woodruff, Susan I.; McCabe, Cameron T.; Hohman, Melinda; Clapp, John D.; Shillington, Audrey M.; Eisenberg, Kimberly; Sise, C. Beth; Castillo, Edward M.; Chan, Theodore C.; Sise, Michael J.

    2016-01-01

    Abstract Emergency department (ED) settings have gained interest as venues for illegal drug misuse prevention and intervention, with researchers and practitioners attempting to capitalize on the intersection of need and opportunity within these settings. This study of 686 adult patients visiting two EDs for various reasons who admitted drug use compared daily cannabis-only users, nondaily cannabis-only users, and other drug users on sociodemographic and drug-related severity outcomes. The three drug use groups did not differ on most sociodemographic factors or medical problem severity scores. Forty-five percent of the sample was identified as having a drug use problem. ED patients who used drugs other than cannabis were at particular risk for high drug use severity indicators and concomitant problems such as psychiatric problems and alcohol use severity. However, 19–29% of cannabis-only users were identified as having problematic drug use. Furthermore, daily cannabis-only users fared less well than nondaily cannabis users with regard to drug use severity indicators and self-efficacy for avoiding drug use. Results may assist emergency medicine providers and medical social workers in matching patients to appropriate intervention. For example, users of drugs other than cannabis (and perhaps heavy, daily cannabis-only users) may need referral to specialty services for further assessment. Enhancement of motivation and self-efficacy beliefs could be an important target of prevention and treatment for cannabis-only users screened in the ED. PMID:27689138

  6. Characteristics of Cannabis-Only and Other Drug Users Who Visit the Emergency Department

    PubMed Central

    Woodruff, Susan I.; McCabe, Cameron T.; Hohman, Melinda; Clapp, John D.; Shillington, Audrey M.; Eisenberg, Kimberly; Sise, C. Beth; Castillo, Edward M.; Chan, Theodore C.; Sise, Michael J.

    2016-01-01

    Abstract Emergency department (ED) settings have gained interest as venues for illegal drug misuse prevention and intervention, with researchers and practitioners attempting to capitalize on the intersection of need and opportunity within these settings. This study of 686 adult patients visiting two EDs for various reasons who admitted drug use compared daily cannabis-only users, nondaily cannabis-only users, and other drug users on sociodemographic and drug-related severity outcomes. The three drug use groups did not differ on most sociodemographic factors or medical problem severity scores. Forty-five percent of the sample was identified as having a drug use problem. ED patients who used drugs other than cannabis were at particular risk for high drug use severity indicators and concomitant problems such as psychiatric problems and alcohol use severity. However, 19–29% of cannabis-only users were identified as having problematic drug use. Furthermore, daily cannabis-only users fared less well than nondaily cannabis users with regard to drug use severity indicators and self-efficacy for avoiding drug use. Results may assist emergency medicine providers and medical social workers in matching patients to appropriate intervention. For example, users of drugs other than cannabis (and perhaps heavy, daily cannabis-only users) may need referral to specialty services for further assessment. Enhancement of motivation and self-efficacy beliefs could be an important target of prevention and treatment for cannabis-only users screened in the ED.

  7. Cerebellar grey-matter deficits, cannabis use and first-episode schizophrenia in adolescents and young adults.

    PubMed

    Cohen, Martin; Rasser, Paul E; Peck, Greg; Carr, Vaughan J; Ward, Philip B; Thompson, Paul M; Johnston, Patrick; Baker, Amanda; Schall, Ulrich

    2012-04-01

    Epidemiological data link adolescent cannabis use to psychosis and schizophrenia, but its contribution to schizophrenia neuropathology remains controversial. First-episode schizophrenia (FES) patients show regional cerebral grey- and white-matter changes as well as a distinct pattern of regional grey-matter loss in the vermis of the cerebellum. The cerebellum possesses a high density of cannabinoid type 1 receptors involved in the neuronal diversification of the developing brain. Cannabis abuse may interfere with this process during adolescent brain maturation leading to 'schizophrenia-like' cerebellar pathology. Magnetic resonance imaging and cortical pattern matching techniques were used to investigate cerebellar grey and white matter in FES patients with and without a history of cannabis use and non-psychiatric cannabis users. In the latter group we found lifetime dose-dependent regional reduction of grey matter in the right cerebellar lobules and a tendency for more profound grey-matter reduction in lobule III with younger age at onset of cannabis use. The overall regional grey-matter differences in cannabis users were within the normal variability of grey-matter distribution. By contrast, FES subjects had lower total cerebellar grey-matter:total cerebellar volume ratio and marked grey-matter loss in the vermis, pedunculi, flocculi and lobules compared to pair-wise matched healthy control subjects. This pattern and degree of grey-matter loss did not differ from age-matched FES subjects with comorbid cannabis use. Our findings indicate small dose-dependent effects of juvenile cannabis use on cerebellar neuropathology but no evidence of an additional effect of cannabis use on FES cerebellar grey-matter pathology.

  8. A Survey of Synthetic Cannabinoid Consumption by Current Cannabis Users

    PubMed Central

    Gunderson, Erik W.; Haughey, Heather M.; Ait-Daoud, Nassima; Joshi, Amruta S.; Hart, Carl L.

    2013-01-01

    Background Despite growing concern about the increased rates of synthetic cannabinoid (SC) use and their effects, only limited data are available that addresses these issues. This study assessed the extent of SC product use and reported effects among a cohort of adult marijuana and tobacco users. Methods A brief telephone interview was conducted with individuals who had given permission to be contacted for future research while screening for a cannabis/nicotine dependence medication development study (NCT01204723). Results Respondents (N= 42: 88% participation rate) were primarily young adults, male, racially diverse, and high school graduates. Nearly all currently smoked tobacco and cannabis, with 86% smoking cannabis on 5 or more days per week. Nearly all (91%) were familiar with SC products, half (50%) reported smoking SC products previously, and a substantial minority (24%) reported current use (i.e., past month). Despite a federal ban on five common SCs, which went into effect on March 1, 2011, a number of respondents reported continued SC product use. Common reasons reported for use included, but were not limited to, seeking a new “high” similar to that produced by marijuana and avoiding drug use detection via a positive urine screen. The primary side effects were trouble thinking clearly, headache, dry mouth, and anxiety. No significant differences were found between synthetic cannabinoid product users (ever or current) and non-users by demographics or other characteristics. Conclusions Among current marijuana and tobacco users, SC product consumption was common and persisted despite a Federal ban. The primary reasons for the use of SC-containing products seem to be to evade drug detection and to experience a marijuana-like high. (Support: DA027131) PMID:24821356

  9. Avoiding emotional bonds: an examination of the dimensions of therapeutic alliance among cannabis users.

    PubMed

    Healey, Alison; Kay-Lambkin, Frances; Bowman, Jenny; Childs, Steven

    2013-01-01

    There is a growing need to provide treatment for cannabis users, yet engaging and maintaining this population in treatment is particularly difficult. Although past research has focused on the importance of therapeutic alliance on drug treatment outcomes, this is the first study to examine the dimensions of therapeutic alliance for cannabis users compared with users of alcohol or other drugs in a naturalistic setting. The acceptability of Internet-delivered interventions for drug and alcohol treatments is also investigated. Participants (n = 77) included clients who were receiving outpatient drug and alcohol treatment at a publicly funded health service, including a Specialist Cannabis Clinic. The results indicated that one particular domain of alliance, Bond, was consistently lower, from both client and clinician perspectives, for current cannabis users relative to those not currently using cannabis. Client perceptions of Bond decreased as the severity of cannabis use increased (r = -0.373, p = 0.02). Cannabis Clinic clients did not report a significantly lower Bond with their clinicians, suggesting that specialized cannabis services may be better placed to provide appropriate treatment for this population than embedding cannabis treatment within traditional drug and alcohol treatment teams. In addition, Internet/computer-based treatments may be one potential way to engage, transition, or retain cannabis users in treatment.

  10. Trajectory of adolescent cannabis use on addiction vulnerability.

    PubMed

    Hurd, Yasmin L; Michaelides, Michael; Miller, Michael L; Jutras-Aswad, Didier

    2014-01-01

    The adolescent brain is a period of dynamic development making it vulnerable to environmental factors such as drug exposure. Of the illicit drugs, cannabis is most used by teenagers since it is perceived by many to be of little harm. This perception has led to a growing number of states approving its legalization and increased accessibility. Most of the debates and ensuing policies regarding cannabis were done without consideration of its impact on one of the most vulnerable population, namely teens, or without consideration of scientific data. We provide an overview of the endocannabinoid system in relation to adolescent cannabis exposure and provide insights regarding factors such as genetics and behavioral traits that confer risk for subsequent addiction. While it is clear that more systematic scientific studies are needed to understand the long-term impact of adolescent cannabis exposure on brain and behavior, the current evidence suggests that it has a far-reaching influence on adult addictive behaviors particularly for certain subsets of vulnerable individuals. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'.

  11. Trajectory of Adolescent Cannabis Use on Addiction Vulnerability

    PubMed Central

    Hurd, Yasmin L.; Michaelides, Michael; Miller, Michael L.; Jutras-Aswad, Didier

    2013-01-01

    The adolescent brain is a period of dynamic development making it vulnerable to environmental factors such as drug exposure. Of the illicit drugs, cannabis is most used by teenagers since it is perceived by many to be of little harm. This perception has led to a growing number of states approving its legalization and increased accessibility. Most of the debates and ensuing policies regarding cannabis were done without consideration of its impact on one of the most vulnerable population, namely teens, or without consideration of scientific data. We provide an overview of the endocannabinoid system in relation to adolescent cannabis exposure and provide insights regarding factors such as genetics and behavioral traits that confer risk for subsequent addiction. While it is clear that more systematic scientific studies are needed to understand the long-term impact of adolescent cannabis exposure on brain and behavior, the current evidence suggests that it has a far-reaching influence on adult addictive behaviors particularly for certain subsets of vulnerable individuals. PMID:23954491

  12. Tobacco May Mask Poorer Episodic Memory among Young Adult Cannabis Users

    PubMed Central

    Schuster, Randi M.; Crane, Natania A.; Mermelstein, Robin; Gonzalez, Raul

    2014-01-01

    Objective Co-occurring cannabis and tobacco use has become increasingly prevalent among young adults, but it is not clear how tobacco use may alter the neurocognitive profile typically observed among cannabis users. Although there is substantial evidence citing cannabis and tobacco's individual impact on episodic memory and related brain structures, few studies have examined the impact of combined cannabis and tobacco use on memory. Method This investigation examined relationships between amount of past year cannabis and tobacco use on four different indices of episodic memory among a sample of young adults who identified cannabis as their drug of choice. Results Results indicated that more cannabis use was linked with poorer initial acquisition, total learning and delayed recall on the Hopkins Verbal Learning Test--Revised (HVLT-R), but only among cannabis users who sporadically smoked cigarettes in the past year. Conversely, amount of past year cannabis use was not associated with episodic memory performance among individuals who more consistently smoked cigarettes in the past year. These differences could not be explained by several relevant potential confounds. Conclusions These findings provide important insight into a potential mechanism (i.e., attenuation of cognitive decrements) that might reinforce use of both substances and hamper cessation attempts among cannabis users who also smoke cigarettes. Ongoing and future research will help to better understand how co-use of cannabis and tobacco impacts memory during acute intoxication and abstinence, and the stability of these associations over time. PMID:25558879

  13. The association between early cannabis use and psychotic-like experiences in a community adolescent sample.

    PubMed

    Hides, Leanne; Lubman, Dan I; Buckby, Joe; Yuen, Hok Pan; Cosgrave, Elizabeth; Baker, Kathryn; Yung, Alison R

    2009-07-01

    Cannabis use has been associated with greater risk of developing psychotic-like experiences (PLEs) and psychosis. This paper aims to determine if different levels of cannabis (lifetime, regular, recent) exposure are associated with PLEs and specific PLE subscales among adolescents. Participants consisted of a community sample of 880 adolescents in Melbourne, Australia. Adolescents were administered the positive symptom scale of the Community Assessment of Psychic Experiences (CAPE) and measures of substance use and depression. Lifetime cannabis use and the frequency of cannabis use in the last year (recent use) were associated with PLEs, primarily the experience of auditory and visual hallucinations (perceptual abnormalities). Low levels of recent cannabis use were more strongly associated with PLEs than more frequent use. These findings indicate that different levels of cannabis exposure were differentially associated with PLEs and highlight the need for early detection and treatment strategies for PLEs and cannabis use in adolescents.

  14. Reliability and validity of the Marijuana Motives Measure among young adult frequent cannabis users and associations with cannabis dependence.

    PubMed

    Benschop, Annemieke; Liebregts, Nienke; van der Pol, Peggy; Schaap, Rick; Buisman, Renate; van Laar, Margriet; van den Brink, Wim; de Graaf, Ron; Korf, Dirk J

    2015-01-01

    The Marijuana Motives Measure (MMM) has so far been examined mainly in student populations, often with relatively limited involvement in cannabis use. This study evaluated the factor structure of the MMM in a demographically mixed sample of 600 young adult (18-30 years) frequent (≥ 3 days per week) cannabis users in the Netherlands. Analysis confirmed a five-factor solution, denoting coping, enhancement, social, conformity and expansion motives. Additionally, the original MMM was extended with two items (boredom and habit), which formed a distinct, internally consistent sixth factor labelled routine motives. In a multivariable logistic regression analysis, coping and routine motives showed significant associations with 12-month DSM-IV cannabis dependence. The results suggest general reliability and validity of the MMM in a heterogeneous population of experienced cannabis users.

  15. Feasibility of Momentary Sampling Assessment of Cannabis Use in Adolescents and Young Adults

    ERIC Educational Resources Information Center

    Black, Shimrit K.; de Moor, Carl; Kendall, Ashley D.; Shrier, Lydia A.

    2014-01-01

    This study examines the feasibility of recruiting and retaining adolescents and young adults with frequent cannabis use for a 2-week momentary sampling study of cannabis use. Participants responded to random signals on a handheld computer with reports of their use. Participants also initiated reports pre- and post-cannabis use. Participants had…

  16. Long lasting consequences of cannabis exposure in adolescence.

    PubMed

    Rubino, T; Parolaro, D

    2008-04-16

    Despite the increasing use of cannabis among adolescents, there are little and often contradictory studies on the long-term neurobiological consequences of cannabis consumption in juveniles. Adolescence is a critical phase for cerebral development, where the endocannabinoid system plays an important role influencing the release and action of different neurotransmitters. Therefore, a strong stimulation by the psychoactive component of marijuana, delta-9-tetrahydrocanabinol (THC), might lead to subtle but lasting neurobiological changes that can affect adult brain functions and behaviour. The literature here summarized by use of experimental animal models, puts forward that heavy cannabis consumption in adolescence may induce subtle changes in the adult brain circuits ending in altered emotional and cognitive performance, enhanced vulnerability for the use of more harmful drugs of abuse in selected individuals, and may represent a risk factor for developing schizophrenia in adulthood. Therefore, the potential problems arising in relation to marijuana consumption in adolescence suggest that this developmental phase is a vulnerable period for persistent adverse effects of cannabinoids.

  17. Disrupted ‘reflection’ impulsivity in cannabis users but not current or former ecstasy users

    PubMed Central

    Clark, L; Roiser, JP; Robbins, TW; Sahakian, BJ

    2009-01-01

    Abstract Evidence for serotonin involvement in impulsivity has generated interest in the measurement of impulsivity in regular ecstasy users, who are thought to display serotonergic dysfunction. However, current findings are inconsistent. Here, we used a recently developed Information Sampling Test to measure ‘reflection’ impulsivity in 46 current ecstasy users, 14 subjects who used ecstasy in the past, 15 current cannabis users and 19 drug-naïve controls. Despite elevated scores on the Impulsivity subscale of the Eysenck Impulsiveness-Venturesomeness-Empathy questionnaire, the current and previous ecstasy users did not differ significantly from the drug-naive controls on the Information Sampling Test. In contrast, the cannabis users sampled significantly less information on the task, and tolerated a lower level of certainty in their decision-making, in comparison to the drug-naive controls. The effect in cannabis users extends our earlier observations in amphetamine- and opiate-dependent individuals (Clark, et al., 2006, Biological Psychiatry 60: 515–522), and suggests that reduced reflection may be a common cognitive style across regular users of a variety of substances. However, the lack of effects in the two ecstasy groups suggests that the relationship between serotonin function, ecstasy use and impulsivity is more complex. PMID:18515464

  18. Psychiatric effects of cannabis use.

    PubMed

    Tunving, K

    1985-09-01

    That cannabis use may provoke mental disturbances is well known to Scandinavian psychiatrists today. A review of the psychiatric aspects of cannabis use is given, and the clinical signs of 70 cases of cannabis psychoses collected in Sweden are described. The bluntness and "amotivation" following chronic cannabis use are discussed. Anxiety reactions, flashbacks, dysphoric reactions and an abstinence syndrome are all sequels of cannabis use. Three risk groups begin to emerge: a) Young teenage cannabis users who lose some of their capacity to learn complex functions and who flee from reality to a world of dreams. With its sedative effect, cannabis could modify such emotions as anger and anxiety and slow down the liberation process of adolescence. b) Heavy daily users, often persons who cannot cope with depression or their life circumstances. c) Psychiatric patients whose resistance to relapses into psychotic reactions might be diminished according to the psychotropic effects of cannabis.

  19. Dose-dependent effects of cannabis on the neural correlates of error monitoring in frequent cannabis users.

    PubMed

    Kowal, Mikael A; van Steenbergen, Henk; Colzato, Lorenza S; Hazekamp, Arno; van der Wee, Nic J A; Manai, Meriem; Durieux, Jeffrey; Hommel, Bernhard

    2015-11-01

    Cannabis has been suggested to impair the capacity to recognize discrepancies between expected and executed actions. However, there is a lack of conclusive evidence regarding the acute impact of cannabis on the neural correlates of error monitoring. In order to contribute to the available knowledge, we used a randomized, double-blind, between-groups design to investigate the impact of administration of a low (5.5 mg THC) or high (22 mg THC) dose of vaporized cannabis vs. placebo on the amplitudes of the error-related negativity (ERN) and error positivity (Pe) in the context of the Flanker task, in a group of frequent cannabis users (required to use cannabis minimally 4 times a week, for at least 2 years). Subjects in the high dose group (n=18) demonstrated a significantly diminished ERN in comparison to the placebo condition (n=19), whereas a reduced Pe amplitude was observed in both the high and low dose (n=18) conditions, as compared to placebo. The results suggest that a high dose of cannabis may affect the neural correlates of both the conscious (late), as well as the initial automatic processes involved in error monitoring, while a low dose of cannabis might impact only the conscious (late) processing of errors.

  20. The Role of Study and Work in Cannabis Use and Dependence Trajectories among Young Adult Frequent Cannabis Users

    PubMed Central

    Liebregts, Nienke; van der Pol, Peggy; Van Laar, Margriet; de Graaf, Ron; van den Brink, Wim; Korf, Dirk J.

    2013-01-01

    Life course theory considers events in study and work as potential turning points in deviance, including illicit drug use. This qualitative study explores the role of occupational life in cannabis use and dependence in young adults. Two and three years after the initial structured interview, 47 at baseline frequent cannabis users were interviewed in-depth about the dynamics underlying changes in their cannabis use and dependence. Overall, cannabis use and dependence declined, including interviewees who quit using cannabis completely, in particular with students, both during their study and after they got employed. Life course theory appeared to be a useful framework to explore how and why occupational life is related to cannabis use and dependence over time. Our study showed that life events in this realm are rather common in young adults and can have a strong impact on cannabis use. While sometimes changes in use are temporary, turning points can evolve from changes in educational and employment situations; an effect that seems to be related to the consequences of these changes in terms of amount of leisure time and agency (i.e., feelings of being in control). PMID:23950748

  1. Poorer frontolimbic white matter integrity is associated with chronic cannabis use, FAAH genotype, and increased depressive and apathy symptoms in adolescents and young adults

    PubMed Central

    Shollenbarger, Skyler G.; Price, Jenessa; Wieser, Jon; Lisdahl, Krista

    2015-01-01

    Background The heaviest period of cannabis use coincides with ongoing white matter (WM) maturation. Further, cannabis-related changes may be moderated by FAAH genotype (rs324420). We examined the association between cannabis use and FAAH genotype on frontolimbic WM integrity in adolescents and emerging adults. We then tested whether observed WM abnormalities were linked with depressive or apathy symptoms. Methods Participants included 37 cannabis users and 37 healthy controls (33 female; ages 18–25). Multiple regressions examined the independent and interactive effects of variables on WM integrity. Results Regular cannabis users demonstrated reduced WM integrity in the bilateral uncinate fasciculus (UNC) (MD, right: p = .009 and left: p = .009; FA, right: p = .04 and left: p = .03) and forceps minor (fMinor) (MD, p = .03) compared to healthy controls. Marginally reduced WM integrity in the cannabis users was found in the left anterior thalamic radiation (ATR) (FA, p = .08). Cannabis group ∗ FAAH genotype interaction predicted WM integrity in bilateral ATR (FA, right: p = .05 and left: p = .001) and fMinor (FA, p = .02). In cannabis users, poorer WM integrity was correlated with increased symptoms of depression and apathy in bilateral ATR and UNC. Conclusions Consistent with prior findings, cannabis use was associated with reduced frontolimbic WM integrity. WM integrity was also moderated by FAAH genotype, in that cannabis-using FAAH C/C carriers and A carrying controls had reduced WM integrity compared to control C/C carriers. Observed frontolimbic white matter abnormalities were linked with increased depressive and apathy symptoms in the cannabis users. PMID:26106535

  2. Swiss Adolescents' and Adults' Perceptions of Cannabis Use: A Qualitative Study

    ERIC Educational Resources Information Center

    Menghrajani, P.; Klaue, K.; Dubois-Arber, F.; Michaud, P.-A.

    2005-01-01

    Few studies have attempted to investigate the nature of adolescents and adults conceptions and perceptions of cannabis use. Our objectives were to explore adolescent and adult perception of use and misuse of cannabis, and their opinions and beliefs about the current legal context and preventive strategies. We used focus group discussions with four…

  3. Cannabis cue reactivity and craving among never, infrequent and heavy cannabis users.

    PubMed

    Henry, Erika A; Kaye, Jesse T; Bryan, Angela D; Hutchison, Kent E; Ito, Tiffany A

    2014-04-01

    Substance cue reactivity is theorized as having a significant role in addiction processes, promoting compulsive patterns of drug-seeking and drug-taking behavior. However, research extending this phenomenon to cannabis has been limited. To that end, the goal of the current work was to examine the relationship between cannabis cue reactivity and craving in a sample of 353 participants varying in self-reported cannabis use. Participants completed a visual oddball task whereby neutral, exercise, and cannabis cue images were presented, and a neutral auditory oddball task while event-related brain potentials (ERPs) were recorded. Consistent with past research, greater cannabis use was associated with greater reactivity to cannabis images, as reflected in the P300 component of the ERP, but not to neutral auditory oddball cues. The latter indicates the specificity of cue reactivity differences as a function of substance-related cues and not generalized cue reactivity. Additionally, cannabis cue reactivity was significantly related to self-reported cannabis craving as well as problems associated with cannabis use. Implications for cannabis use and addiction more generally are discussed.

  4. Alterations of monetary reward and punishment processing in chronic cannabis users: an FMRI study.

    PubMed

    Enzi, Björn; Lissek, Silke; Edel, Marc-Andreas; Tegenthoff, Martin; Nicolas, Volkmar; Scherbaum, Norbert; Juckel, Georg; Roser, Patrik

    2015-01-01

    Alterations in reward and punishment processing have been reported in adults suffering from long-term cannabis use. However, previous findings regarding the chronic effects of cannabis on reward and punishment processing have been inconsistent. In the present study, we used functional magnetic resonance imaging (fMRI) to reveal the neural correlates of reward and punishment processing in long-term cannabis users (n = 15) and in healthy control subjects (n = 15) with no history of drug abuse. For this purpose, we used the well-established Monetary Incentive Delay (MID) task, a reliable experimental paradigm that allows the differentiation between anticipatory and consummatory aspects of reward and punishment processing. Regarding the gain anticipation period, no significant group differences were observed. In the left caudate and the left inferior frontal gyrus, cannabis users were - in contrast to healthy controls - not able to differentiate between the conditions feedback of reward and control. In addition, cannabis users showed stronger activations in the left caudate and the bilateral inferior frontal gyrus following feedback of no punishment as compared to healthy controls. We interpreted these deficits in dorsal striatal functioning as altered stimulus-reward or action-contingent learning in cannabis users. In addition, the enhanced lateral prefrontal activation in cannabis users that is related to non-punishing feedback may reflect a deficit in emotion regulation or cognitive reappraisal in these subjects. PMID:25799565

  5. Alterations of monetary reward and punishment processing in chronic cannabis users: an FMRI study.

    PubMed

    Enzi, Björn; Lissek, Silke; Edel, Marc-Andreas; Tegenthoff, Martin; Nicolas, Volkmar; Scherbaum, Norbert; Juckel, Georg; Roser, Patrik

    2015-01-01

    Alterations in reward and punishment processing have been reported in adults suffering from long-term cannabis use. However, previous findings regarding the chronic effects of cannabis on reward and punishment processing have been inconsistent. In the present study, we used functional magnetic resonance imaging (fMRI) to reveal the neural correlates of reward and punishment processing in long-term cannabis users (n = 15) and in healthy control subjects (n = 15) with no history of drug abuse. For this purpose, we used the well-established Monetary Incentive Delay (MID) task, a reliable experimental paradigm that allows the differentiation between anticipatory and consummatory aspects of reward and punishment processing. Regarding the gain anticipation period, no significant group differences were observed. In the left caudate and the left inferior frontal gyrus, cannabis users were - in contrast to healthy controls - not able to differentiate between the conditions feedback of reward and control. In addition, cannabis users showed stronger activations in the left caudate and the bilateral inferior frontal gyrus following feedback of no punishment as compared to healthy controls. We interpreted these deficits in dorsal striatal functioning as altered stimulus-reward or action-contingent learning in cannabis users. In addition, the enhanced lateral prefrontal activation in cannabis users that is related to non-punishing feedback may reflect a deficit in emotion regulation or cognitive reappraisal in these subjects.

  6. Cannabis craving in response to laboratory-induced social stress among racially diverse cannabis users: The impact of social anxiety disorder.

    PubMed

    Buckner, Julia D; Zvolensky, Michael J; Ecker, Anthony H; Jeffries, Emily R

    2016-04-01

    Social anxiety disorder appears to be a risk factor for cannabis-related problems. Although it is presumed that increases in cannabis craving during elevated social anxiety reflect an intent to cope with greater negative affectivity, it is unclear whether increases in physiological arousal during social stress are related to cannabis craving, especially among those with social anxiety disorder. Similarly, no studies have assessed motivational reasons for cannabis use during elevated social stress. Thus, the current study tested whether increases in state social anxiety (measured subjectively and via physiological arousal) were related to greater cannabis craving among 126 current cannabis users (88.9% with cannabis use disorder, 31.7% with social anxiety disorder, 54.0% non-Hispanic Caucasian) randomly assigned to either a social interaction or reading task. As predicted, cannabis users in the social interaction condition reported greater cannabis craving than those in the reading condition. This effect was particularly evident among those with social anxiety disorder. Although physiological arousal did not moderate the relationship between condition and craving, coping motives were the most common reasons cited for wanting to use cannabis and were reported more among those in the social interaction task. These experimental results uniquely add to a growing literature suggesting the importance of elevated state social anxiety (especially among those with social anxiety disorder) in cannabis use vulnerability processes. PMID:26839322

  7. Cannabis craving in response to laboratory-induced social stress among racially diverse cannabis users: The impact of social anxiety disorder.

    PubMed

    Buckner, Julia D; Zvolensky, Michael J; Ecker, Anthony H; Jeffries, Emily R

    2016-04-01

    Social anxiety disorder appears to be a risk factor for cannabis-related problems. Although it is presumed that increases in cannabis craving during elevated social anxiety reflect an intent to cope with greater negative affectivity, it is unclear whether increases in physiological arousal during social stress are related to cannabis craving, especially among those with social anxiety disorder. Similarly, no studies have assessed motivational reasons for cannabis use during elevated social stress. Thus, the current study tested whether increases in state social anxiety (measured subjectively and via physiological arousal) were related to greater cannabis craving among 126 current cannabis users (88.9% with cannabis use disorder, 31.7% with social anxiety disorder, 54.0% non-Hispanic Caucasian) randomly assigned to either a social interaction or reading task. As predicted, cannabis users in the social interaction condition reported greater cannabis craving than those in the reading condition. This effect was particularly evident among those with social anxiety disorder. Although physiological arousal did not moderate the relationship between condition and craving, coping motives were the most common reasons cited for wanting to use cannabis and were reported more among those in the social interaction task. These experimental results uniquely add to a growing literature suggesting the importance of elevated state social anxiety (especially among those with social anxiety disorder) in cannabis use vulnerability processes.

  8. Developmental trajectories of adolescent cannabis use and their relationship to young adult social and behavioural adjustment: A longitudinal study of Australian youth.

    PubMed

    Scholes-Balog, Kirsty E; Hemphill, Sheryl A; Evans-Whipp, Tracy J; Toumbourou, John W; Patton, George C

    2016-02-01

    This study aimed to identify distinct developmental trajectories (sub-groups of individuals who showed similar longitudinal patterns) of cannabis use among Australian adolescents, and to examine associations between trajectory group membership and measures of social and behavioural adjustment in young adulthood. Participants (n=852, 53% female) were part of the International Youth Development Study. Latent class growth analysis was used to identify distinct trajectories of cannabis use frequency from average ages 12 to 19, across 6 waves of data. Logistic regression analyses and analyses of covariance were used to examine relationships between trajectory group membership and young adult (average age: 21) adjustment, controlling for a range of covariates. Three trajectories were identified: abstainers (62%), early onset users (11%), and late onset occasional users (27%). The early onset users showed a higher frequency of antisocial behaviour, violence, cannabis use, cannabis-related harms, cigarette use, and alcohol harms, compared to the abstinent group in young adulthood. The late onset occasional users reported a higher frequency of cannabis use, cannabis-related harms, illicit drug use, and alcohol harms, compared to the abstinent group in young adulthood. There were no differences between the trajectory groups on measures of employment, school completion, post-secondary education, income, depression/anxiety, or alcohol use problems. In conclusion, early onset of cannabis use, even at relatively low frequency during adolescence, is associated with poorer adjustment in young adulthood. Prevention and intervention efforts to delay or prevent uptake of cannabis use should be particularly focussed on early adolescence prior to age 12.

  9. Developmental trajectories of adolescent cannabis use and their relationship to young adult social and behavioural adjustment: A longitudinal study of Australian youth.

    PubMed

    Scholes-Balog, Kirsty E; Hemphill, Sheryl A; Evans-Whipp, Tracy J; Toumbourou, John W; Patton, George C

    2016-02-01

    This study aimed to identify distinct developmental trajectories (sub-groups of individuals who showed similar longitudinal patterns) of cannabis use among Australian adolescents, and to examine associations between trajectory group membership and measures of social and behavioural adjustment in young adulthood. Participants (n=852, 53% female) were part of the International Youth Development Study. Latent class growth analysis was used to identify distinct trajectories of cannabis use frequency from average ages 12 to 19, across 6 waves of data. Logistic regression analyses and analyses of covariance were used to examine relationships between trajectory group membership and young adult (average age: 21) adjustment, controlling for a range of covariates. Three trajectories were identified: abstainers (62%), early onset users (11%), and late onset occasional users (27%). The early onset users showed a higher frequency of antisocial behaviour, violence, cannabis use, cannabis-related harms, cigarette use, and alcohol harms, compared to the abstinent group in young adulthood. The late onset occasional users reported a higher frequency of cannabis use, cannabis-related harms, illicit drug use, and alcohol harms, compared to the abstinent group in young adulthood. There were no differences between the trajectory groups on measures of employment, school completion, post-secondary education, income, depression/anxiety, or alcohol use problems. In conclusion, early onset of cannabis use, even at relatively low frequency during adolescence, is associated with poorer adjustment in young adulthood. Prevention and intervention efforts to delay or prevent uptake of cannabis use should be particularly focussed on early adolescence prior to age 12. PMID:26414206

  10. Cannabis Reclassification: What Is the Message to the Next Generation of Cannabis Users?

    ERIC Educational Resources Information Center

    McCrystal, Patrick; Winning, Kerry

    2009-01-01

    At the beginning of 2004 the UK government downgraded the legal status of cannabis from a Class B to a Class C drug. Following a review of this decision two years later, cannabis remained a Class C substance--which for some contrasted with the potential harmful social and health effects associated with its use, particularly for young people. These…

  11. Electrophysiological evidence of early attentional bias to drug-related pictures in chronic cannabis users.

    PubMed

    Asmaro, Deyar; Carolan, Patrick L; Liotti, Mario

    2014-01-01

    Behavioral and electrophysiological correlates of attentional bias to cannabis-related cues were investigated in a marijuana dependent group and a non-user group employing a drug Stroop task in which cannabis-related, negative and neutral images were presented. Behaviorally, cannabis users were less accurate during drug-containing blocks than non-users. Electrophysiologically, in chronic marijuana-users, an early positive ERP enhancement over left frontal scalp (EAP, 200-350ms) was present in response to drug-containing blocks relative to negative blocks. This effect was absent in the non-user group. Furthermore, drug-containing blocks gave rise to enhanced voltage of a posterior P300 (300-400ms), and a posterior sustained slow wave (LPP, 400-700ms) relative to negative blocks. However, such effects were similar between cannabis users and non-users. Brain source imaging in cannabis users revealed a generator for the EAP effect to drug stimuli in left ventromedial prefrontal cortex/medial orbitofrontal cortex, a region active in fMRI studies of drug cue-reactivity and a target of the core dopaminergic mesolimbic pathway involved in the processing of substances of abuse. This study identifies the timing and brain localization of an ERP correlate of early attentional capture to drug-related pictures in chronic marijuana users. The EAP to drug cues may identify a new electrophysiological marker with clinical implications for predicting abstinence versus relapse or to evaluate treatment interventions.

  12. High School Students’ Use of Electronic Cigarettes to Vaporize Cannabis

    PubMed Central

    Kong, Grace; Camenga, Deepa R.; Cavallo, Dana A.; Krishnan-Sarin, Suchitra

    2015-01-01

    BACKGROUND AND OBJECTIVES: Electronic cigarette (e-cigarette) use is increasing rapidly among high school (HS) students. Of concern, e-cigarettes can be used to vaporize cannabis, although use rates among adolescents are unknown. We evaluated lifetime rates of using e-cigarettes to vaporize cannabis among all lifetime e-cigarette users (27.9%), all lifetime cannabis users (29.2%), and lifetime users of both e-cigarettes and cannabis (18.8%); common means of vaporizing cannabis including hash oil, wax infused with Δ-9-tetrahydrocannabinol (THC), and dried cannabis; and demographic predictors of using e-cigarettes to vaporize cannabis. METHODS: In the spring of 2014, 3847 Connecticut HS students completed an anonymous survey assessing e-cigarette and cannabis use. RESULTS: Vaporizing cannabis using e-cigarettes was common among lifetime e-cigarette users, lifetime cannabis users, and lifetime dual users (e-cigarette 18.0%, cannabis 18.4%, dual users 26.5%). Students reported using e-cigarettes to vaporize hash oil (e-cigarette 15.4%, cannabis 15.5%, dual users 22.9%) and wax infused with THC (e-cigarette 10.0%, cannabis 10.2%, dual users 14.8%) and using portable electronic vaporizers to vaporize dried cannabis leaves (e-cigarette 19.6%, lifetime cannabis 23.1%, lifetime dual users 29.1%). Binary logistic regression indicated that male students (odds ratio [OR] = 2.05), younger students (OR = 0.64), lifetime e-cigarette users (OR = 5.27), and lifetime cannabis users (OR = 40.89) were most likely to vaporize cannabis using e-cigarettes. Rates also differed by HS attended. CONCLUSIONS: Rates of vaporizing cannabis using e-cigarettes were high. These findings raise concerns about the lack of e-cigarette regulations and the potential use of e-cigarettes for purposes other than vaping nicotine. PMID:26347431

  13. Parietal Lobe Volume Deficits in Adolescents with Schizophrenia and Adolescents with Cannabis Use Disorders

    ERIC Educational Resources Information Center

    Kumra, Sanjiv; Robinson, Paul; Tambyraja, Rabindra; Jensen, Daniel; Schimunek, Caroline; Houri, Alaa; Reis, Tiffany; Lim, Kelvin

    2012-01-01

    Objective: In early-onset schizophrenia (EOS), the earliest structural brain volumetric abnormalities appear in the parietal cortices. Early exposure to cannabis may represent an environmental risk factor for developing schizophrenia. This study characterized cerebral cortical gray matter structure in adolescents in regions of interest (ROIs) that…

  14. Characteristics and Predictors of Health Problems from Use among High-Frequency Cannabis Users in a Canadian University Student Population

    ERIC Educational Resources Information Center

    Fischer, Benedikt; Dawe, Meghan; Mcguire, Fraser; Shuper, Paul A; Jones, Wayne; Rudzinski, Katherine; Rehm, Jurgen

    2012-01-01

    Aims: Assess key cannabis use, risk and outcome characteristics among high-frequency cannabis users within a university student sample in Toronto, Canada. Methods: N = 134 active universities students (ages of 18-28) using cannabis at least three times per week were recruited by mass advertisement, telephone-screened and anonymously assessed by an…

  15. [Epidemiological news in cannabis].

    PubMed

    Beck, François; Guignard, Romain; Richard, Jean-Baptiste

    2013-12-01

    Cannabis is by far the most common illicit drug in France. Among 15-64 years, 32.1% have already experienced it and 8.4% declare they have used it at least once during the past twelve months. In Europe, France is one of the countries with the highest prevalence. Males are markedly more often cannabis users than females and this gender gap tends to increase with the level of use. During the last two decades, the part of the population having tried cannabis did not stop increasing, under the influence of a generalization of the cannabis experience among young people. However, cannabis last year prevalence is rather stable since 2000. Cannabis lifetime use is very rare at the beginning of middle school (1.5% in sixth grade at age 11) but increases in the following years (11% of the pupils of the eighth grade, 24% of the pupils of the ninth grade). Cannabis use at a younger age is related to subsequent onset of cannabis related problems. Adolescent and young adults from high socioeconomic status (SES) more often try cannabis than young people from lower SES. However, cannabis regular use is associated with bad school results, truancy and early school leaving, and with a lower SES. Young people from high SES indeed dispose of greater sociocultural resources to master and regulate their consumption and are more often conscious of their interest not to be tipped over in problematic use.

  16. Mismatch Negativity and P50 Sensory Gating in Abstinent Former Cannabis Users

    PubMed Central

    Broyd, Samantha J.; Greenwood, Lisa-marie; van Hell, Hendrika H.; Croft, Rodney J.; Coyle, Hannah; Lee-Bates, Ben; Todd, Juanita; Johnstone, Stuart J.; Michie, Patricia T.; Solowij, Nadia

    2016-01-01

    Prolonged heavy exposure to cannabis is associated with impaired cognition and brain functional and structural alterations. We recently reported attenuated mismatch negativity (MMN) and altered P50 sensory gating in chronic cannabis users. This study investigated the extent of brain functional recovery (indexed by MMN and P50) in chronic users after cessation of use. Eighteen ex-users (median 13.5 years prior regular use; median 3.5 years abstinence) and 18 nonusers completed (1) a multifeature oddball task with duration, frequency, and intensity deviants and (2) a P50 paired-click paradigm. Trend level smaller duration MMN amplitude and larger P50 ratios (indicative of poorer sensory gating) were observed in ex-users compared to controls. Poorer P50 gating correlated with prior duration of cannabis use. Duration of abstinence was positively correlated with duration MMN amplitude, even after controlling for age and duration of cannabis use. Impaired sensory gating and attenuated MMN amplitude tended to persist in ex-users after prolonged cessation of use, suggesting a lack of full recovery. An association with prolonged duration of prior cannabis use may indicate persistent cannabis-related alterations to P50 sensory gating. Greater reductions in MMN amplitude with increasing abstinence (positive correlation) may be related to either self-medication or an accelerated aging process. PMID:27019754

  17. Mismatch Negativity and P50 Sensory Gating in Abstinent Former Cannabis Users.

    PubMed

    Broyd, Samantha J; Greenwood, Lisa-marie; van Hell, Hendrika H; Croft, Rodney J; Coyle, Hannah; Lee-Bates, Ben; Todd, Juanita; Johnstone, Stuart J; Michie, Patricia T; Solowij, Nadia

    2016-01-01

    Prolonged heavy exposure to cannabis is associated with impaired cognition and brain functional and structural alterations. We recently reported attenuated mismatch negativity (MMN) and altered P50 sensory gating in chronic cannabis users. This study investigated the extent of brain functional recovery (indexed by MMN and P50) in chronic users after cessation of use. Eighteen ex-users (median 13.5 years prior regular use; median 3.5 years abstinence) and 18 nonusers completed (1) a multifeature oddball task with duration, frequency, and intensity deviants and (2) a P50 paired-click paradigm. Trend level smaller duration MMN amplitude and larger P50 ratios (indicative of poorer sensory gating) were observed in ex-users compared to controls. Poorer P50 gating correlated with prior duration of cannabis use. Duration of abstinence was positively correlated with duration MMN amplitude, even after controlling for age and duration of cannabis use. Impaired sensory gating and attenuated MMN amplitude tended to persist in ex-users after prolonged cessation of use, suggesting a lack of full recovery. An association with prolonged duration of prior cannabis use may indicate persistent cannabis-related alterations to P50 sensory gating. Greater reductions in MMN amplitude with increasing abstinence (positive correlation) may be related to either self-medication or an accelerated aging process. PMID:27019754

  18. Cue-Reactivity in Cannabis-Dependent Adolescents

    PubMed Central

    Nickerson, Lisa D.; Ravichandran, Caitlin; Lundahl, Leslie H.; Rodolico, John; Dunlap, Steven; Trksak, George H.; Lukas, Scott E.

    2010-01-01

    We measured event-related potentials (ERPs) with a craving manipulation to investigate the neural correlates of drug cue-reactivity in 13 cannabis-dependent (CD) adolescents (ages 14–17). The P300 responses to marijuana (MJ) pictures (MJ-P300) and control pictures (C-P300) were assessed after handling neutral objects and again after handling MJ paraphernalia (MJP). Self-reported drug craving and heart rates also were measured. MJ-P300 were larger than C-P300 (p<0.001) and both the MJ-P300 and craving increased significantly after handling MJP (p=0.002 and p=0.003, respectively), with no association between the magnitude of craving and MJ-P300. Heart rates were not affected by handling MJP. Our results show that CD adolescents have an attentional bias to MJ stimuli that increases after handling marijuana paraphernalia. Generally, our results are consistent with what has been reported for adult heavy chronic cannabis smokers; although there were some differences that require further investigation. PMID:21142334

  19. Family Stressors and Adolescent Cannabis Use: A Pathway to Problem Use.

    ERIC Educational Resources Information Center

    Butters, Jennifer E.

    2002-01-01

    Estimates the direct impact of family stressors on the progression to problem cannabis use among adolescents in Ontario. Results suggest that family stressors have direct and indirect effects increasing the probability of cannabis use outcomes. The implications of these more complex associations between factors believed to influence adolescent…

  20. Social Skills as Precursors of Cannabis Use in Young Adolescents: A Trails Study

    ERIC Educational Resources Information Center

    Griffith-Lendering, Merel F. H.; Huijbregts, Stephan C. J.; Huizink, Anja C.; Ormel, Hans; Verhulst, Frank C.; Vollebergh, Wilma A. M.; Swaab, Hanna

    2011-01-01

    Social skills (cooperation, assertion, and self-control) were assessed by teachers for a longitudinal cohort of (pre)adolescents, with measurements at average ages 11.1 (baseline) and 16.3 years (follow-up). Prospective associations with participants' self-reported use of cannabis, (age of) onset of cannabis use, and frequency of use at follow-up…

  1. Early Cannabis Use and Schizotypal Personality Disorder Symptoms from Adolescence to Middle Adulthood

    PubMed Central

    Anglin, Deidre M.; Corcoran, Cheryl; Brown, Alan; Chen, Henian; Lighty, Quenesha; Brook, Judith; Cohen, Patricia

    2012-01-01

    Background While increasing evidence suggests that cannabis use may play a role in the development of schizophrenia in some young people, less is known about the strength and specificity of its relationship to latent schizophrenia liability, i.e., schizotypal personality disorder traits. Aims Determine the predictive value of cannabis use during childhood and early adolescence on schizotypal personality disorder (SPD) symptoms projecting into adulthood, using a community-based longitudinal cohort from upstate New York. Method Prospective data from 804 participants was used to determine associations between early cannabis use and later schizotypal symptoms, accounting for important potential confounds (e.g., adolescent schizotypal symptoms). Results Cannabis use with onset prior to age 14 strongly predicted SPD symptoms in adulthood, independent of early adolescent SPD symptoms, major depression, anxiety disorder, other drug use, and cigarette use. There was no interaction effect of early cannabis use and early adolescent SPD symptoms on SPD symptoms into adulthood. Conclusions Our data provide further support for a strong association of early cannabis use with the development of symptoms characteristic of schizophrenia spectrum disorders. As with studies in schizophrenia, early SPD symptoms could not fully explain the association of early cannabis use with later schizotypal symptoms. The mechanisms that underlie the association of cannabis use and schizotypal symptoms in a developmental context deserve further exploration. PMID:22325079

  2. Telling true from false: cannabis users show increased susceptibility to false memories

    PubMed Central

    Riba, J; Valle, M; Sampedro, F; Rodríguez-Pujadas, A; Martínez-Horta, S; Kulisevsky, J; Rodríguez-Fornells, A

    2015-01-01

    Previous studies on the neurocognitive impact of cannabis use have found working and declarative memory deficits that tend to normalize with abstinence. An unexplored aspect of cognitive function in chronic cannabis users is the ability to distinguish between veridical and illusory memories, a crucial aspect of reality monitoring that relies on adequate memory function and cognitive control. Using functional magnetic resonance imaging, we show that abstinent cannabis users have an increased susceptibility to false memories, failing to identify lure stimuli as events that never occurred. In addition to impaired performance, cannabis users display reduced activation in areas associated with memory processing within the lateral and medial temporal lobe (MTL), and in parietal and frontal brain regions involved in attention and performance monitoring. Furthermore, cannabis consumption was inversely correlated with MTL activity, suggesting that the drug is especially detrimental to the episodic aspects of memory. These findings indicate that cannabis users have an increased susceptibility to memory distortions even when abstinent and drug-free, suggesting a long-lasting compromise of memory and cognitive control mechanisms involved in reality monitoring. PMID:25824306

  3. Blunted psychotomimetic and amnestic effects of delta-9-tetrahydrocannabinol in frequent users of cannabis.

    PubMed

    D'Souza, Deepak Cyril; Ranganathan, Mohini; Braley, Gabriel; Gueorguieva, Ralitza; Zimolo, Zoran; Cooper, Thomas; Perry, Edward; Krystal, John

    2008-09-01

    Cannabis is one of the most widely used illicit substances and there is growing interest in the association between cannabis use and psychosis. Delta-9-Tetrahydrocannabinol (Delta-9-THC) the principal active ingredient of cannabis has been shown to induce psychotomimetic and amnestic effects in healthy individuals. Whether people who frequently use cannabis are either protected from or are tolerant to these effects of Delta-9-THC has not been established. In a 3-day, double-blind, randomized, placebo-controlled study, the dose-related effects of 0, 2.5, and 5 mg intravenous Delta-9-THC were studied in 30 frequent users of cannabis and compared to 22 healthy controls. Delta-9-THC (1) produced transient psychotomimetic effects and perceptual alterations; (2) impaired memory and attention; (3) increased subjective effects of 'high'; (4) produced tachycardia; and (5) increased serum cortisol in both groups. However, relative to controls, frequent users showed blunted responses to the psychotomimetic, perceptual altering, cognitive impairing, anxiogenic, and cortisol increasing effects of Delta-9-THC but not to its euphoric effects. Frequent users also had lower prolactin levels. These data suggest that frequent users of cannabis are either inherently blunted in their response to, and/or develop tolerance to the psychotomimetic, perceptual altering, amnestic, endocrine, and other effects of cannabinoids.

  4. Evaluation of herbal cannabis characteristics by medical users: a randomized trial

    PubMed Central

    Ware, Mark A; Ducruet, Thierry; Robinson, Ann R

    2006-01-01

    Background Cannabis, in herbal form, is widely used as self-medication by patients with diseases such as HIV/AIDS and multiple sclerosis suffering from symptoms including pain, muscle spasticity, stress and insomnia. Valid clinical studies of herbal cannabis require a product which is acceptable to patients in order to maximize adherence to study protocols. Methods We conducted a randomized controlled crossover trial of 4 different herbal cannabis preparations among 8 experienced and authorized cannabis users with chronic pain. Preparations were varied with respect to grind size, THC content and humidity. Subjects received each preparation on a separate day and prepared the drug in their usual way in a dedicated and licensed clinical facility. They were asked to evaluate the products based on appearance (smell, colour, humidity, grind size, ease of preparation and overall appearance) and smoking characteristics (burn rate, hotness, harshness and taste). Five-point Likert scores were assigned to each characteristic. Scores were compared between preparations using ANOVA. Results Seven subjects completed the study, and the product with highest THC content (12%), highest humidity (14%) and largest grind size (10 mm) was rated highest overall. Significant differences were noted between preparations on overall appearance and colour (p = 0.003). Discussion While the small size of the study precludes broad conclusions, the study shows that medical cannabis users can appreciate differences in herbal product. A more acceptable cannabis product may increase recruitment and retention in clinical studies of medical cannabis. PMID:17101054

  5. Cannabis use disorders are comparatively prevalent among nonwhite racial/ethnic groups and adolescents: A national study

    PubMed Central

    Wu, Li-Tzy; Brady, Kathleen T.; Mannelli, Paolo; Killeen, Therese K.

    2014-01-01

    The racial/ethnic composition of the US population is shifting, with the nonwhite population growing faster than whites. We examined cannabis use disorder (CUD) prevalences and correlates in seven racial/ethnic groups. We included cannabis use (CU) prevalence as a comparison. Data were from the 2005–2011 National Surveys on Drug Use and Health (N=394,400). Substance use among respondents aged ≥12 years was assessed by computer-assisted, self-interviewing methods. The following were included as control variables: age, sex, family income, government assistance, county type, residential stability, major depressive episode history, arrest history, nicotine dependence, alcohol disorder, and survey year. Past-year CU prevalence increased significantly from 10.45% in 2005 to 11.41–11.54% during 2009–2011. Compared with whites, mixed-race individuals had higher odds of CU; Asian Americans and Hispanics had lower odds of CU. There were no significant yearly changes in CUD prevalence in the sample during 2005–2011 (1.58–1.73%). Compared with whites, individuals who were mixed-race, black, and Native American had higher odds of CUD; Asian Americans had lower odds. In aggregate, 15.35% of past-year cannabis users met criteria for a CUD in the 12-month period. Past-year cannabis users who were black, Native American, Hispanic, or Asian American had higher odds of CUD than white users. In each racial/ethnic group, adolescent cannabis users generally showed greater odds of CUD than adult users. Behavioral health indicators (major depressive episode, arrest history, nicotine dependence, alcohol disorder) were associated with CU and CUD. In conclusion, CUD disproportionally affects nonwhite groups and youth. PMID:24342767

  6. Cannabis use disorders are comparatively prevalent among nonwhite racial/ethnic groups and adolescents: a national study.

    PubMed

    Wu, Li-Tzy; Brady, Kathleen T; Mannelli, Paolo; Killeen, Therese K

    2014-03-01

    The racial/ethnic composition of the US population is shifting, with the nonwhite population growing faster than whites. We examined cannabis use disorder (CUD) prevalences and correlates in seven racial/ethnic groups. We included cannabis use (CU) prevalence as a comparison. Data were from the 2005-2011 National Surveys on Drug Use and Health (N = 394,400). Substance use among respondents aged ≥12 years was assessed by computer-assisted, self-interviewing methods. The following were included as control variables: age, sex, family income, government assistance, county type, residential stability, major depressive episode history, arrest history, nicotine dependence, alcohol disorder, and survey year. Past-year CU prevalence increased significantly from 10.45% in 2005 to 11.41-11.54% during 2009-2011. Compared with whites, mixed-race individuals had higher odds of CU; Asian Americans and Hispanics had lower odds of CU. There were no significant yearly changes in CUD prevalence in the sample during 2005-2011 (1.58-1.73%). Compared with whites, individuals who were mixed-race, black, and Native American had higher odds of CUD; Asian Americans had lower odds. In aggregate, 15.35% of past-year cannabis users met criteria for a CUD in the 12-month period. Past-year cannabis users who were black, Native American, Hispanic, or Asian American had higher odds of CUD than white users. In each racial/ethnic group, adolescent cannabis users generally showed greater odds of CUD than adult users. Behavioral health indicators (major depressive episode, arrest history, nicotine dependence, alcohol disorder) were associated with CU and CUD. In conclusion, CUD disproportionally affects nonwhite groups and youth.

  7. Increased ventral striatal BOLD activity during non-drug reward anticipation in cannabis users.

    PubMed

    Nestor, Liam; Hester, Robert; Garavan, Hugh

    2010-01-01

    Despite an increased understanding of the pharmacology and long-term cognitive effects of cannabis in humans, there has been no research to date examining its chronic effects upon reward processing in the brain. Motivational theories regarding long-term drug use posit contrasting predictions with respect to how drug users are likely to process non-drug incentives. The reward deficiency syndrome (RDS) of addiction posits that there are deficits in dopamine (DA) motivational circuitry for non-drug rewards, such that only drugs of abuse are capable of normalizing DA in the ventral striatum (VS). Alternatively, the opponent process theory (OPT) holds that in individuals prone to drug use, there exists some form of mesolimbic hyperactivity, in which there is a bias towards reward-centred behaviour concomitant with impulsivity. The current study examined BOLD responses during reward and loss anticipation and their outcome deliveries in 14 chronic cannabis users and 14 drug-naive controls during a monetary incentive delay (MID) task. Despite no significant behavioural differences between the two groups, cannabis users had significantly more right VS BOLD activity during reward anticipation. Correlation analyses demonstrated that this right VS BOLD response was significantly correlated with life-time use and reported life-time cannabis joints consumed. No correlations between cannabis abstinence and BOLD responses were observed. We also observed a number of group differences following outcome deliveries, most notably hypoactivity in the left insula cortex in response to loss and loss avoidance outcome notifications in the cannabis group. These results may suggest hypersensitivity during instrumental response anticipation for non-drug rewards and a hyposensitivity to loss outcomes in chronic cannabis users; the implications of which are discussed with respect to the potentially sensitizing effects of cannabis for other rewards.

  8. Increased ventral striatal BOLD activity during non-drug reward anticipation in cannabis users

    PubMed Central

    Nestor, Liam; Hester, Robert; Garavan, Hugh

    2009-01-01

    Despite an increased understanding of the pharmacology and long-term cognitive effects of cannabis in humans, there has been no research to date examining its chronic effects upon reward processing in the brain. Motivational theories regarding long-term drug use posit contrasting predictions with respect to how drug users are likely to process non-drug incentives. The reward deficiency syndrome (RDS) of addiction posits that there are deficits in dopamine (DA) motivational circuitry for non-drug rewards, such that only drugs of abuse are capable of normalizing DA in the ventral striatum (VS). Alternatively, the opponent process theory (OPT) holds that in individuals prone to drug use, there exists some form of mesolimbic hyperactivity, in which there is a bias towards reward-centred behaviour concomitant with impulsivity. The current study examined BOLD responses during reward and loss anticipation and their outcome deliveries in 14 chronic cannabis users and 14 drug-naïve controls during a monetary incentive delay (MID) task. Despite no significant behavioural differences between the two groups, cannabis users had significantly more right VS BOLD activity during reward anticipation. Correlation analyses demonstrated that this right VS BOLD response was significantly correlated with life-time use and reported life-time cannabis joints consumed. No correlations between cannabis abstinence and BOLD responses were observed. We also observed a number of group differences following outcome deliveries, most notably hypoactivity in the left insula cortex in response to loss and loss avoidance outcome notifications in the cannabis group. These results may suggest hypersensitivity during instrumental response anticipation for non-drug rewards and a hyposensitivity to loss outcomes in chronic cannabis users; the implications of which are discussed with respect to the potentially sensitizing effects of cannabis for other rewards. PMID:19631753

  9. Personality Characteristics of Adolescents with Hallucinogen, Methamphetamine, and Cannabis Dependence: A Comparative Study

    ERIC Educational Resources Information Center

    Palmer, Glen A.; Daiss, Doyle D.

    2005-01-01

    A comparison of personality factors on scales of the Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A) was conducted with a sample of adolescents referred to a residential substance abuse treatment program. A total of sixty adolescents identified with hallucinogen (n = 20), cannabis (n = 20), or methamphetamine (n = 20) as their drug…

  10. Abnormal striatal circuitry and intensified novelty seeking among adolescents who abuse methamphetamine and cannabis.

    PubMed

    Churchwell, John C; Carey, Paul D; Ferrett, Helen L; Stein, Dan J; Yurgelun-Todd, Deborah A

    2012-01-01

    It has been hypothesized that changes in striatal-mediated dopamine modulation during adolescence may increase the risk for initiating substance abuse as a result of its fundamental role in arbitrating reward sensitivity and motivation during learning and decision making. However, substance abuse during adolescence may also significantly modify striatal structure and function and concomitantly alter reward sensitivity and action control while this brain region is undergoing remodeling. In the present investigation, to assess the relationship of methamphetamine (Meth) or Meth and cannabis (CA) abuse to regional striatal morphology, we acquired structural magnetic resonance images, using a 3T Siemens Trio scanner, from three groups of adolescents composed of healthy controls (n = 10), Meth abusers (n = 9) and combined Meth and CA abusers (Meth+CA, n = 8). We also assessed novelty seeking using the novelty seeking subscale of Cloninger's Tridimensional Character Inventory. The results indicate that adolescent Meth+CA abusers have increased regional striatal volume and show intensified novelty seeking in contrast to the controls. The degree of Meth exposure was also positively correlated with regional striatal volume and novelty seeking in both the Meth and Meth+CA users. These preliminary findings support theories that propose a role for the striatum in adolescent substance abuse and further indicate that novelty seeking may be related to the initiation of, or sustained, drug use.

  11. Disrupted Gamma-Band Neural Oscillations During Coherent Motion Perception in Heavy Cannabis Users

    PubMed Central

    Skosnik, Patrick D; Krishnan, Giri P; D'Souza, Deepak C; Hetrick, William P; O'Donnell, Brian F

    2014-01-01

    Previous work in animals and humans has shown that exogenous cannabinoids disrupt time-locked, evoked gamma oscillations (30–80 Hz). However, no studies to date have examined the effect of cannabis on non-time-locked, induced gamma oscillations during more complex Gestalt perception. The current study therefore utilized electroencephalography (EEG) to examine gamma oscillations during coherent motion perception in heavy cannabis users and controls. Chronic cannabis users (n=24; 12 h abstinence before study; positive 11-nor-9-carboxy-delta-9-tetrahydrocannabinol urine levels) and cannabis-naive controls (n=23) were evaluated. Stimuli consisted of random dot kinetograms (RDKs) that subjects passively viewed during three different conditions: coherent motion, incoherent motion, and static. Time × frequency analysis on EEG data was performed using Fourier-based mean trial power (MTP). Transient event-related potentials (ERPs) to stimulus onset (visual N100 and P200 components) were also evaluated. The results showed that the coherent motion condition produced a robust increase in neural activity in the gamma range (induced power from 40 to 59 Hz) as compared with the incoherent motion and static conditions. As predicted, the cannabis group showed significant reductions in induced gamma power in the coherent condition relative to healthy controls. No differences were observed between the groups in the N100 or P200 components, indicating intact primary sensory processing. Finally, cannabis users showed a trend toward increased scores on the Chapman Perceptual Aberration Scale (PAS) that was positively correlated with total years of active cannabis use. These data suggest that cannabis use may interfere with the generation of induced gamma-band neural oscillations that could in part mediate the perceptual-altering effects of exogenous cannabinoids. PMID:24990428

  12. Performance of Young Adult Cannabis Users on Neurocognitive Measures of Impulsive Behavior and their Relationship to Symptoms of Cannabis Use Disorders

    PubMed Central

    Gonzalez, Raul; Schuster, Randi Melissa; Mermelstein, Robin J.; Vassileva, Jasmin; Martin, Eileen M.; Diviak, Kathleen R.

    2012-01-01

    Recent studies suggest that abstinent cannabis users show deficits on neurocognitive laboratory tasks of impulsive behavior. But results are mixed and less is known on the performance of non-treatment seeking, young adult cannabis users. Importantly, relationships between performance on measures of impulsive behavior and symptoms of cannabis addiction remain relatively unexplored. We compared young adult current cannabis users (CU, n = 65) and non-using controls (NU, n = 65) on several laboratory measures of impulsive behavior, as well as on a measure of episodic memory commonly impacted by cannabis use. The CU group performed more poorly than the NU group on the Hopkins Verbal Learning Test-Revised Total Immediate Recall and Delayed Recall. No significant differences were observed on the measures of impulsive behavior (i.e., Iowa Gambling Task [IGT], Go-Stop Task, Monetary Choice Questionnaire, Balloon Analogue Risk Task). We examined relationships between neurocognitive performance and symptoms of cannabis use disorder symptoms (DSM-IV CUD) among the CU group, which revealed that poorer IGT performance was associated with more symptoms of DSM-IV CUD. Our results show poorer memory performance among young adult cannabis users relative to healthy controls, but no differences on measures of impulsive behavior. However, performance on a specific type of impulsive behavior (i.e., poorer decision-making) was associated with more cannabis use disorder symptoms. These results provide preliminary evidence to suggest that decision-making deficits may be more strongly associated with problems experienced from cannabis use, rather than solely being a consequence of cannabis use, per se. PMID:22882144

  13. Performance of young adult cannabis users on neurocognitive measures of impulsive behavior and their relationship to symptoms of cannabis use disorders.

    PubMed

    Gonzalez, Raul; Schuster, Randi Melissa; Mermelstein, Robin J; Vassileva, Jasmin; Martin, Eileen M; Diviak, Kathleen R

    2012-01-01

    Recent studies suggest that abstinent cannabis users show deficits on neurocognitive laboratory tasks of impulsive behavior. But results are mixed, and less is known on the performance of non-treatment-seeking, young adult cannabis users. Importantly, relationships between performance on measures of impulsive behavior and symptoms of cannabis addiction remain relatively unexplored. We compared young adult current cannabis users (CU, n = 65) and nonusing controls (NU, n = 65) on several laboratory measures of impulsive behavior, as well as on a measure of episodic memory commonly impacted by cannabis use. The CU group performed more poorly than the NU group on the Hopkins Verbal Learning Test-Revised Total Immediate Recall and Delayed Recall. No significant differences were observed on the measures of impulsive behavior (i.e., Iowa Gambling Task, IGT; Go-Stop Task; Monetary Choice Questionnaire; Balloon Analogue Risk Task). We examined relationships between neurocognitive performance and symptoms of cannabis use disorder symptoms (Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition, DSM-IV CUD) among the CU group, which revealed that poorer IGT performance was associated with more symptoms of DSM-IV CUD. Our results show poorer memory performance among young adult cannabis users than among healthy controls, but no differences on measures of impulsive behavior. However, performance on a specific type of impulsive behavior (i.e., poorer decision making) was associated with more cannabis use disorder symptoms. These results provide preliminary evidence to suggest that decision-making deficits may be more strongly associated with problems experienced from cannabis use, rather than solely being a consequence of cannabis use, per se. PMID:22882144

  14. Mismatch negativity in tobacco-naïve cannabis users and its alteration with acute nicotine administration.

    PubMed

    Impey, Danielle; El-Marj, Nicole; Parks, Andrea; Choueiry, Joelle; Fisher, Derek; Knott, Verner J

    2015-09-01

    Chronic cannabis use may interact with factors, such as age of onset of cannabis use, family history, and genetic factors, to elicit schizophrenia (SZ)-like symptoms, including sensory and cognitive deficits. However, evidence of a relationship between cannabis use and cognitive impairment is confounded by concomitant use of tobacco. The objective of this study was to compare tobacco-naïve cannabis users with individuals without a history of tobacco/cannabis use on the auditory mismatch negativity (MMN) event-related potential (ERP), a neural measure of auditory deviance detection which is diminished in SZ. An exploratory arm of the study, conducted within a randomized, double-blind, placebo controlled design, examined the acute effects of nicotine gum (6mg) on MMN in cannabis users. MMN was recorded in response to 5 deviant stimuli within an optimal MMN paradigm in 44 healthy, non-tobacco smoking volunteers aged 18-26. Cannabis users (n=21) started smoking cannabis prior to age 17, at least 1 joint per month. To examine the effects of chronicity, users were grouped into relatively heavy long-term (HLT; n=11) users and light short-term (LST; n=10) users. Impaired deviance detection was shown in cannabis users vs. nonusers as reflected by a smaller MMN to duration deviants. Chronicity of use was also associated with MMN alterations, as HLTs displayed a reduced duration and gap MMN vs. LSTs. Compared with placebo, nicotine treatment enhanced select MMN deviants in cannabis user subgroups. As deficits associated with early and persistent cannabis use are similar to those seen in SZ, these dose-dependant disturbances in early sensory processing with cannabis use may be one cognitive pathway which mediates an increased risk for SZ in vulnerable youth, and be influenced by concurrent cigarette smoking behavior.

  15. Mismatch negativity in tobacco-naïve cannabis users and its alteration with acute nicotine administration.

    PubMed

    Impey, Danielle; El-Marj, Nicole; Parks, Andrea; Choueiry, Joelle; Fisher, Derek; Knott, Verner J

    2015-09-01

    Chronic cannabis use may interact with factors, such as age of onset of cannabis use, family history, and genetic factors, to elicit schizophrenia (SZ)-like symptoms, including sensory and cognitive deficits. However, evidence of a relationship between cannabis use and cognitive impairment is confounded by concomitant use of tobacco. The objective of this study was to compare tobacco-naïve cannabis users with individuals without a history of tobacco/cannabis use on the auditory mismatch negativity (MMN) event-related potential (ERP), a neural measure of auditory deviance detection which is diminished in SZ. An exploratory arm of the study, conducted within a randomized, double-blind, placebo controlled design, examined the acute effects of nicotine gum (6mg) on MMN in cannabis users. MMN was recorded in response to 5 deviant stimuli within an optimal MMN paradigm in 44 healthy, non-tobacco smoking volunteers aged 18-26. Cannabis users (n=21) started smoking cannabis prior to age 17, at least 1 joint per month. To examine the effects of chronicity, users were grouped into relatively heavy long-term (HLT; n=11) users and light short-term (LST; n=10) users. Impaired deviance detection was shown in cannabis users vs. nonusers as reflected by a smaller MMN to duration deviants. Chronicity of use was also associated with MMN alterations, as HLTs displayed a reduced duration and gap MMN vs. LSTs. Compared with placebo, nicotine treatment enhanced select MMN deviants in cannabis user subgroups. As deficits associated with early and persistent cannabis use are similar to those seen in SZ, these dose-dependant disturbances in early sensory processing with cannabis use may be one cognitive pathway which mediates an increased risk for SZ in vulnerable youth, and be influenced by concurrent cigarette smoking behavior. PMID:26188167

  16. Rapid elimination of Carboxy-THC in a cohort of chronic cannabis users.

    PubMed

    Lewis, John; Molnar, Anna; Allsop, David; Copeland, Jan; Fu, Shanlin

    2016-01-01

    Urinary 11-nor-Δ(9)-tetrahydrocannabinol-9-carboxylic acid (Carboxy-THC) concentrations, normalised to creatinine output, have been demonstrated to be a useful tool in the interpretation of the results of a series of urine tests for cannabis. These tests, often termed historical data, can be used to identify potential chronic cannabis users who may present occupational health and safety risks within the workplace. Conversely, the data can also be used to support employee claims of previous regular, rather than recent, cannabis use. This study aimed at examining the mean elimination of Carboxy-THC in 37 chronic users undergoing voluntary abstinence over a 2-week period. Urine specimens were collected prior to the study and after 1 and 2 weeks of abstinence. Carboxy-THC levels in urine were measured by gas chromatography-mass spectrometry (GC-MS) following alkaline hydrolysis, organic solvent extraction and derivatisation to form its pentafluoropropionic derivative. The creatinine-normalised Carboxy-THC concentrations declined rapidly over the 2 weeks of abstinence period and the majority of chronic cannabis users (73%) reduced their urinary Carboxy-THC levels to below the 15-μg/L confirmatory cutoff within that time. The study further highlights the value of historical urinary Carboxy-THC data as a means of identifying potential occupational health and safety risks among chronic cannabis users.

  17. Cannabis use history and characteristics of quit attempts: a comparison study of treatment-seeking and non-treatment-seeking cannabis users.

    PubMed

    Pacek, Lauren R; Vandrey, Ryan

    2014-12-01

    Cannabis is the most commonly used illicit substance worldwide, and cannabis use disorders (CUDs) are correspondingly high. Increased demand for treatment and relatively low rates of positive clinical outcomes has led to a large scientific investment in the development of interventions for the treatment of CUD. Much of this research is conducted with cannabis users who are not seeking treatment at the time of study participation, and it is unknown whether these individuals are representative of those who seek treatment. This study contrasted samples of cannabis users participating in screening interviews for treatment and nontreatment research studies. Several differences between groups emerged: Treatment-seekers were more likely to be female (43% vs. 29%), older (33.4 vs. 29.7 years), and have longer cannabis use histories compared with non-treatment-seekers (p = .007). Treatment-seekers were more likely to report experiencing guilt after using cannabis and to feel that cannabis use has been a problem for them. Additionally, treatment-seekers reported a greater mean number of reasons for making a quit attempt, experiencing a greater number of withdrawal symptoms, and employing more coping strategies during prior quit attempts. Despite the aforementioned differences, the 2 groups were similar on several key characteristics, particularly with regards to current levels of cannabis use and related problems. PMID:25150537

  18. Cannabis use history and characteristics of quit attempts: a comparison study of treatment-seeking and non-treatment-seeking cannabis users.

    PubMed

    Pacek, Lauren R; Vandrey, Ryan

    2014-12-01

    Cannabis is the most commonly used illicit substance worldwide, and cannabis use disorders (CUDs) are correspondingly high. Increased demand for treatment and relatively low rates of positive clinical outcomes has led to a large scientific investment in the development of interventions for the treatment of CUD. Much of this research is conducted with cannabis users who are not seeking treatment at the time of study participation, and it is unknown whether these individuals are representative of those who seek treatment. This study contrasted samples of cannabis users participating in screening interviews for treatment and nontreatment research studies. Several differences between groups emerged: Treatment-seekers were more likely to be female (43% vs. 29%), older (33.4 vs. 29.7 years), and have longer cannabis use histories compared with non-treatment-seekers (p = .007). Treatment-seekers were more likely to report experiencing guilt after using cannabis and to feel that cannabis use has been a problem for them. Additionally, treatment-seekers reported a greater mean number of reasons for making a quit attempt, experiencing a greater number of withdrawal symptoms, and employing more coping strategies during prior quit attempts. Despite the aforementioned differences, the 2 groups were similar on several key characteristics, particularly with regards to current levels of cannabis use and related problems.

  19. fMRI study of neural sensitization to hedonic stimuli in long-term, daily cannabis users.

    PubMed

    Filbey, Francesca M; Dunlop, Joseph; Ketcherside, Ariel; Baine, Jessica; Rhinehardt, Tyler; Kuhn, Brittany; DeWitt, Sam; Alvi, Talha

    2016-10-01

    Although there is emergent evidence illustrating neural sensitivity to cannabis cues in cannabis users, the specificity of this effect to cannabis cues as opposed to a generalized hyper-sensitivity to hedonic stimuli has not yet been directly tested. Using fMRI, we presented 53 daily, long-term cannabis users and 68 non-using controls visual and tactile cues for cannabis, a natural reward, and, a sensory-perceptual control object to evaluate brain response to hedonic stimuli in cannabis users. The results showed an interaction between group and reward type such that the users had greater response during cannabis cues relative to natural reward cues (i.e., fruit) in the orbitofrontal cortex, striatum, anterior cingulate gyrus, and ventral tegmental area compared to non-users (cluster-threshold z = 2.3, P < 0.05). In the users, there were positive brain-behavior correlations between neural response to cannabis cues in fronto-striatal-temporal regions and subjective craving, marijuana-related problems, withdrawal symptoms, and levels of THC metabolites (cluster-threshold z = 2.3, P < 0.05). These findings demonstrate hyper-responsivity, and, specificity of brain response to cannabis cues in long-term cannabis users that are above that of response to natural reward cues. These observations are concordant with incentive sensitization models suggesting sensitization of mesocorticolimbic regions and disruption of natural reward processes following drug use. Although the cross-sectional nature of this study does not provide information on causality, the positive correlations between neural response and indicators of cannabis use (i.e., THC levels) suggest that alterations in the reward system are, in part, related to cannabis use. Hum Brain Mapp 37:3431-3443, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

  20. fMRI study of neural sensitization to hedonic stimuli in long-term, daily cannabis users.

    PubMed

    Filbey, Francesca M; Dunlop, Joseph; Ketcherside, Ariel; Baine, Jessica; Rhinehardt, Tyler; Kuhn, Brittany; DeWitt, Sam; Alvi, Talha

    2016-10-01

    Although there is emergent evidence illustrating neural sensitivity to cannabis cues in cannabis users, the specificity of this effect to cannabis cues as opposed to a generalized hyper-sensitivity to hedonic stimuli has not yet been directly tested. Using fMRI, we presented 53 daily, long-term cannabis users and 68 non-using controls visual and tactile cues for cannabis, a natural reward, and, a sensory-perceptual control object to evaluate brain response to hedonic stimuli in cannabis users. The results showed an interaction between group and reward type such that the users had greater response during cannabis cues relative to natural reward cues (i.e., fruit) in the orbitofrontal cortex, striatum, anterior cingulate gyrus, and ventral tegmental area compared to non-users (cluster-threshold z = 2.3, P < 0.05). In the users, there were positive brain-behavior correlations between neural response to cannabis cues in fronto-striatal-temporal regions and subjective craving, marijuana-related problems, withdrawal symptoms, and levels of THC metabolites (cluster-threshold z = 2.3, P < 0.05). These findings demonstrate hyper-responsivity, and, specificity of brain response to cannabis cues in long-term cannabis users that are above that of response to natural reward cues. These observations are concordant with incentive sensitization models suggesting sensitization of mesocorticolimbic regions and disruption of natural reward processes following drug use. Although the cross-sectional nature of this study does not provide information on causality, the positive correlations between neural response and indicators of cannabis use (i.e., THC levels) suggest that alterations in the reward system are, in part, related to cannabis use. Hum Brain Mapp 37:3431-3443, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:27168331

  1. Psychosocial correlates of adolescent cannabis use: data from the Italian subsample of the second International Self-Reported Delinquency study.

    PubMed

    Maniglio, Roberto; Innamorati, Marco

    2014-01-01

    To provide a comprehensive picture of the whole spectrum of psychosocial factors potentially associated with adolescent cannabis use, bivariate and multivariate analyses were used to assess a variety of social, demographic, psychological, and behavioral correlates of last-month cannabis use and age of first use among 6,838 students. Results showed that only family problems, alcohol and/or other drug use/misuse, deviant behavior, and victimization were independently associated with either recent cannabis use or early onset of cannabis use when multiple, interacting factors were considered. Certain family and behavioral factors might be more important than other psychosocial correlates of adolescent cannabis use. PMID:25115199

  2. Cannabis use and neurocognitive functioning in a non-clinical sample of users

    PubMed Central

    Thames, April D.; Arbid, Natalie; Sayegh, Philip

    2014-01-01

    Objective With the recent debates over marijuana legalization and increases in use, it is critical to examine its role in cognition. While many studies generally support the adverse acute effects of cannabis on neurocognition, the non-acute effects remain less clear. The current study used a cross-sectional design to examine relationships between recent and past cannabis use on neurocognitive functioning in a non-clinical adult sample. Method One hundred and fifty-eight participants were recruited through fliers distributed around local college campuses and the community. All participants completed the Brief Drug Use History Form, the Structured Clinical Interview for DSM-IV Disorders, and neurocognitive assessment, and underwent urine toxicology screening. Participants consisted of recent users (n = 68), past users (n = 41), and non-users (n = 49). Results Recent users demonstrated significantly (p < .05) worse performance than non-users across cognitive domains of attention/working memory (M = 42.4, SD = 16.1 vs. M = 50.5, SD = 10.2), information processing speed (M = 44.3, SD = 7.3 vs. M = 52.1, SD = 11.0), and executive functioning (M = 43.6, SD = 13.4 vs. M = 48.6, SD = 7.2). There were no statistically significant differences between recent users and past users on neurocognitive performance. Frequency of cannabis use in the last 4 weeks was negatively associated with global neurocognitive performance and all individual cognitive domains. Similarly, amount of daily cannabis use was negatively associated with global neurocognitive performance and individual cognitive domains. Conclusions Our results support the widespread adverse effects of cannabis use on neurocognitive functioning. Although some of these adverse effects appear to attenuate with abstinence, past users' neurocognitive functioning was consistently lower than non-users. PMID:24556155

  3. Associations between Cannabinoid Receptor-1 (CNR1) Variation and Hippocampus and Amygdala Volumes in Heavy Cannabis Users

    PubMed Central

    Schacht, Joseph P; Hutchison, Kent E; Filbey, Francesca M

    2012-01-01

    Heavy cannabis users display smaller amygdalae and hippocampi than controls, and genetic variation accounts for a large proportion of variance in liability to cannabis dependence (CD). A single nucleotide polymorphism in the cannabis receptor-1 gene (CNR1), rs2023239, has been associated with CD diagnosis and intermediate phenotypes, including abstinence-induced withdrawal, cue-elicited craving, and parahippocampal activation to cannabis cues. This study compared hippocampal and amygdalar volumes (potential CD intermediate phenotypes) between heavy cannabis users and healthy controls, and analyzed interactions between group, rs2023239 variation, and the volumes of these structures. Ninety-four heavy cannabis users participated, of whom 37 (14 men, 23 women; mean age=27.8) were matched to 37 healthy controls (14 men, 23 women; mean age=27.3) for case-control analyses. Controlling for total intracranial volume and other confounding variables, matched cannabis users had smaller bilateral hippocampi (left, p=0.002; right, p=0.001) and left amygdalae (p=0.01) than controls. When genotype was considered in the case-control analyses, there was a group by genotype interaction, such that the rs2023239 G allele predicted lower volume of bilateral hippocampi among cannabis users relative to controls (both p<0.001). This interaction persisted when all 94 cannabis users were compared to controls. There were no group by genotype interactions on amygdalar volume. These data replicate previous findings of reduced hippocampal and amygdalar volume among heavy cannabis users, and suggest that CNR1 rs2023239 variation may predispose smaller hippocampal volume after heavy cannabis use. This association should be tested in future studies of brain volume differences in CD. PMID:22669173

  4. Creating the cannabis user: a post-structuralist analysis of the re-classification of cannabis in the United Kingdom (2004-2005).

    PubMed

    Acevedo, Beatriz

    2007-05-01

    In January 2004 the British government announced that cannabis would be reclassified from Classes B to C, taking into account its level of harmfulness for human health and considering the penalties for possession and supplying. It was argued by the Government, that cannabis reclassification would save some resources and stop the criminalisation of otherwise law-abiding citizens. One year later, in 2005 the discussion about cannabis reclassification shifted from the argument about efficiency in the use of resources toward a debate about the effects of cannabis on mental health. The purpose of this article is to determine what happened between these two moments, and how the discussion originally formulated in terms of public management and efficiency became a matter of both mental health and criminality. Using a post-Structuralist approach, based on selected ideas from the French philosopher Michel Foucault, and supported by extensive research, this article proposes that the political decision regarding cannabis reclassification can be understood as part of the re-definition of the 'cannabis problem' and hence, the creation of a new type of 'cannabis user'. Although the debate took place in the United Kingdom, the main arguments can be extended to other reforms on cannabis legislation in other European countries. PMID:17689364

  5. Adverse effects of cannabis.

    PubMed

    2011-01-01

    Cannabis, Cannabis sativa L., is used to produce a resin that contains high levels of cannabinoids, particularly delta9-tetrahydrocannabinol (THC), which are psychoactive substances. Although cannabis use is illegal in France and in many other countries, it is widely used for its relaxing or euphoric effects, especially by adolescents and young adults. What are the adverse effects of cannabis on health? During consumption? And in the long term? Does cannabis predispose users to the development of psychotic disorders? To answer these questions, we reviewed the available evidence using the standard Prescrire methodology. The long-term adverse effects of cannabis are difficult to evaluate. Since and associated substances, with or without the user's knowledge. Tobacco and alcohol consumption, and particular lifestyles and behaviours are often associated with cannabis use. Some traits predispose individuals to the use of psychoactive substances in general. The effects of cannabis are dosedependent.The most frequently report-ed adverse effects are mental slowness, impaired reaction times, and sometimes accentuation of anxiety. Serious psychological disorders have been reported with high levels of intoxication. The relationship between poor school performance and early, regular, and frequent cannabis use seems to be a vicious circle, in which each sustains the other. Many studies have focused on the long-term effects of cannabis on memory, but their results have been inconclusive. There do not * About fifteen longitudinal cohort studies that examined the influence of cannabis on depressive thoughts or suicidal ideation have yielded conflicting results and are inconclusive. Several longitudinal cohort studies have shown a statistical association between psychotic illness and self-reported cannabis use. However, the results are difficult to interpret due to methodological problems, particularly the unknown reliability of self-reported data. It has not been possible to

  6. Adverse effects of cannabis.

    PubMed

    2011-01-01

    Cannabis, Cannabis sativa L., is used to produce a resin that contains high levels of cannabinoids, particularly delta9-tetrahydrocannabinol (THC), which are psychoactive substances. Although cannabis use is illegal in France and in many other countries, it is widely used for its relaxing or euphoric effects, especially by adolescents and young adults. What are the adverse effects of cannabis on health? During consumption? And in the long term? Does cannabis predispose users to the development of psychotic disorders? To answer these questions, we reviewed the available evidence using the standard Prescrire methodology. The long-term adverse effects of cannabis are difficult to evaluate. Since and associated substances, with or without the user's knowledge. Tobacco and alcohol consumption, and particular lifestyles and behaviours are often associated with cannabis use. Some traits predispose individuals to the use of psychoactive substances in general. The effects of cannabis are dosedependent.The most frequently report-ed adverse effects are mental slowness, impaired reaction times, and sometimes accentuation of anxiety. Serious psychological disorders have been reported with high levels of intoxication. The relationship between poor school performance and early, regular, and frequent cannabis use seems to be a vicious circle, in which each sustains the other. Many studies have focused on the long-term effects of cannabis on memory, but their results have been inconclusive. There do not * About fifteen longitudinal cohort studies that examined the influence of cannabis on depressive thoughts or suicidal ideation have yielded conflicting results and are inconclusive. Several longitudinal cohort studies have shown a statistical association between psychotic illness and self-reported cannabis use. However, the results are difficult to interpret due to methodological problems, particularly the unknown reliability of self-reported data. It has not been possible to

  7. Cannabis withdrawal syndrome: An important diagnostic consideration in adolescents presenting with disordered eating.

    PubMed

    Chesney, Tyler; Matsos, Laura; Couturier, Jennifer; Johnson, Natasha

    2014-03-01

    Although previously thought to have no withdrawal symptoms, there is now convergent evidence for a cannabis withdrawal syndrome (CWS), criteria for its diagnosis, and evidence of its impact in the adolescent population. Cannabis withdrawal syndrome represents an important and under-recognized consideration in adolescents with disordered eating. We describe three clinical cases of adolescents presenting to an eating disorders program with primary complaints of gastrointestinal symptoms, food avoidance, and associated weight loss. They did not meet the criteria for an eating disorder, but did fulfill the DSM-5 criteria for CWS. This report emphasizes the importance of considering the impact of heavy cannabis use in adolescents presenting with gastrointestinal complaints, and eating disorder symptoms, including weight loss. PMID:24281745

  8. Do cigarette smoking and alcohol consumption associate with cannabis use and problem gambling among Spanish adolescents?

    PubMed

    Míguez Varela, M Del Carmen; Becoña, Elisardo

    2015-03-01

    This article examined the relationship between cigarette smoking or alcohol consumption and cannabis use and problem gambling among a random and representative sample of 1447 Spanish adolescents (797 males and 650 females with an average of 12.8 years). An ad-hoc questionnaire was used to assess cigarette smoking, alcohol consumption (beer, wine and spirits) and cannabis use. Gambling was assessed with the South Oaks Gambling Screen Revised for Adolescents (SOGS-RA). Results indicated a positive and significant association between cigarette smoking and alcohol consumption and the two aforementioned variables. A larger percentage of cigarette smokers and drinkers was found among those participants who had consumed cannabis before or scored significantly in problem gambling. Additionally, multiple regression analysis confirmed that both cigarette smoking and alcohol consumption (beer and wine) were the most determinant variables for cannabis use and problem gambling.

  9. Do cigarette smoking and alcohol consumption associate with cannabis use and problem gambling among Spanish adolescents?

    PubMed

    Míguez Varela, M Del Carmen; Becoña, Elisardo

    2015-01-01

    This article examined the relationship between cigarette smoking or alcohol consumption and cannabis use and problem gambling among a random and representative sample of 1447 Spanish adolescents (797 males and 650 females with an average of 12.8 years). An ad-hoc questionnaire was used to assess cigarette smoking, alcohol consumption (beer, wine and spirits) and cannabis use. Gambling was assessed with the South Oaks Gambling Screen Revised for Adolescents (SOGS-RA). Results indicated a positive and significant association between cigarette smoking and alcohol consumption and the two aforementioned variables. A larger percentage of cigarette smokers and drinkers was found among those participants who had consumed cannabis before or scored significantly in problem gambling. Additionally, multiple regression analysis confirmed that both cigarette smoking and alcohol consumption (beer and wine) were the most determinant variables for cannabis use and problem gambling. PMID:25879473

  10. Adolescent Tobacco and Cannabis Use: Young Adult Outcomes from the Ontario Child Health Study

    ERIC Educational Resources Information Center

    Georgiades, Katholiki; Boyle, Michael H.

    2007-01-01

    Background: This study examines the longitudinal associations between adolescent tobacco and cannabis use and young adult functioning. Methods: Data for analysis come from the Ontario Child Health Study (OCHS), a prospective study of child health, psychiatric disorder and adolescent substance use in a general population sample that began in 1983,…

  11. [Cognitive mechanisms in risky decision-making in cannabis users].

    PubMed

    J R, Alameda-Bailén; M P, Salguero-Alcañiz; A, Merchán-Clavellino; S, Paíno-Quesada

    2014-01-01

    The relationship between the use of cannabis and the decision-making processes was explored. A computerized version of the Iowa Gambling Task (Cards Software) in its normal and reverse version was used, and the Prospect Valence Learning (PVL) model, which characterize the process of decision-making based on the parameters: Recency, Consistency, Loss aversion and Utility shape, was applied. Seventy-three cannabis consumers and a control group with 73 nonconsumers participated in the study. In the normal mode, subjects in the control group scored higher than cannabis consumers. Both groups showed consistent responses and aversion to loss. Nonconsumers showed greater influence of the gain-loss frequency, while consumers were more influenced by the magnitude of the gain-loss. The influence of immediate choices was higher among consumers who showed a quick oblivion while in the control group this process was more gradual. In the reverse mode, task performance was better among control group participants. Both groups showed consistency, loss aversion, more influenced by the magnitude of the gain-loss, and low influence of immediate elections. The results show the relationship between drug use and the decision-making processes, being consistent with the results obtained in other studies where consumers had worse results than control group. Moreover, the PVL parameters allow to adequately characterize decision-making. This confirms the relationship between drug use and decision-making by either the vulnerability prior to consumption or the neurotoxicity of drugs.

  12. A preliminary examination of how serotonergic polymorphisms influence brain response following an adolescent cannabis intervention.

    PubMed

    Feldstein Ewing, Sarah W; Mead, Hilary K; Yezhuvath, Uma; Dewitt, Sam; Hutchison, Kent E; Filbey, Francesca M

    2012-11-30

    Given the link between depression, anxiety, and cannabis abuse, a serotonin receptor (rs6311) and transporter polymorphism (rs2020936) were examined as moderators of neural response as measured by functional magnetic resonance imaging following a psychosocial treatment for cannabis use disorders (CUDs). While the proposed hypotheses were unsupported, we found that the rs6311 C allele was significantly related to brain activation (medial frontal gyrus, precuneus), indicating the role of this serotonin receptor in adolescent treatment response. PMID:23217578

  13. Cannabis Use Frequency and Use-Related Impairment among African American and White Users: The Impact of Cannabis Use Motives

    PubMed Central

    Shah, Sonia M.; Dean, Kimberlye E.; Zvolensky, Michael J.

    2015-01-01

    Objectives Cannabis use motives are differentially related to cannabis-related impairment and coping motives appear to have the strongest relation to use-related impairment. However, it is currently unknown whether African American individuals differ from White persons in reasons for using cannabis. It is also unknown whether motives’ relations to cannabis use and related impairment vary as a function of race. The present study examined the role of race on cannabis use motives and tested whether motives’ relations with cannabis use and related impairment differed by race. Design The sample consisted of 111 (67.6% non-Hispanic White, 32.4% African American) current cannabis-using adults. Results African American participants did not significantly differ from White participants on cannabis use frequency or use-related impairment. African American participants endorsed more social motives than White participants. Race interacted with social, coping, and conformity motives to predict cannabis-related impairment such that these motives were positively related to cannabis impairment among African American, but not White, participants. Conclusion Although African American and White participants do not differ in their cannabis use frequency or cannabis-related impairment, they appear to use cannabis for different reasons. Further, conformity, coping, and social motives were differentially associated with cannabis-related impairment as a function of race. Findings suggest motives for cannabis use should be contexualized in the context of race. PMID:26264291

  14. Clinical Approach to the Heavy Cannabis User in the Age of Medical Marijuana.

    PubMed

    Cermak, Timmen L

    2016-01-01

    This article begins with a case vignette exemplifying the common clinical problem of heavy marijuana users. The epidemiology and basic science underlying cannabis dependence is outlined, followed by clinical strategies for basing a therapeutic alliance on known research findings and using motivational interviewing to deal with typical patterns of denial.

  15. Sizing the cannabis market: a demand-side and user-specific approach in seven European countries.

    PubMed

    van Laar, Margriet; Frijns, Tom; Trautmann, Franz; Lombi, Linda

    2013-06-01

    Demand-based estimates of total cannabis consumption rarely consider differences among different user types and variation across countries. To describe cannabis consumption patterns and estimate annual consumption for different user types across EU Member States, a web survey in Bulgaria, Czech Republic, Italy, the Netherlands, Portugal, Sweden and United Kingdom (England & Wales) collected data on cannabis use patterns from 3,922 persons who had consumed cannabis at least once in the past year. They were classified into four groups based on their number of use days in the past 12 months: infrequent users or chippers (<11 days), occasional users (11-50 days), regular users (51-250 days) and intensive users (>250 days). User type specific data on typical amounts consumed were matched with data on numbers of users per user type estimated from existing population surveys, taking differences in mode of consumption, age and gender into account. Estimates were supplemented with data from populations of problem users to compensate for under coverage. Results showed remarkably consistent differences among user groups across countries. Both the average number of units consumed per typical use day and the average amount of cannabis consumed per unit increased across user types of increasing frequency of use. In all countries except Portugal, intensive users formed the smallest group of cannabis users but were responsible for the largest part of total annual cannabis consumption. Annual cannabis consumption varied across countries but confidence intervals were wide. Results are compared with previous estimates and discussed in the context of improving estimation methods.

  16. Adolescent exposure to cannabis as a risk factor for psychiatric disorders.

    PubMed

    Rubino, Tiziana; Zamberletti, Erica; Parolaro, Daniela

    2012-01-01

    Adolescence represents a critical period for brain development and the endocannabinoid system plays a crucial role in the regulation of neuronal refinement during this period. Cannabis is the most consumed drug among adolescent people and its heavy use may affect maturational refinement by disrupting the regulatory role of the endocannabinoid system. In animals, adolescent cannabinoid exposure has been reported to cause long-term impairment in specific components of learning and memory and to differentially affect emotional reactivity with milder effects on anxiety behaviour and more pronounced effects on depression-like behaviour. Moreover, adolescent exposure to cannabinoids might represent a risk factor for developing psychotic-like symptoms at adulthood. Also epidemiological studies suggest that heavy adolescent cannabis use may increase the risk of cognitive abnormalities, psychotic illness, mood disorders and other illicit substance use later in life. In conclusion, the available data point to the hypothesis that heavy cannabis use in adolescence could increase the risk of developing psychiatric disorders, especially in people who already have a vulnerability to develop a psychiatric syndrome. Only few papers have investigated the neurobiological substrates of this vulnerability, thus further studies are needed to clarify the molecular mechanisms underlying the effect of cannabis on the adolescent brain.

  17. Health effects of using cannabis for therapeutic purposes: a gender analysis of users' perspectives.

    PubMed

    Bottorff, Joan L; Bissell, Laura J L; Balneaves, Lynda G; Oliffe, John L; Kang, H Bindy K; Capler, N Rielle; Buxton, Jane A; O'Brien, Robin K

    2011-01-01

    The purpose of this qualitative study was to describe how individuals who self-report therapeutic use of cannabis perceive its health effects. Data from 23 individual interviews were transcribed and analyzed. Understandings of gendered roles and identities were used to explore the data and interpret differences in perceptions. Descriptions of the health benefits of cannabis for therapeutic purposes included cannabis as life preserving, a disease therapy, a medicine for the mind, a means for self-management, and a way to manage addiction. Self-management of risks focused on the potential effects of excessive use, smoking-related risks, and purchasing precautions. Although the reports of women and men were similar in many respects, there were important differences in patterns and practices of use that reflected gender influences. Insights from the study provide direction for developing gender-specific information to support decision making and usage for therapeutic users.

  18. Swiss adolescents' and adults' perceptions of cannabis use: a qualitative study.

    PubMed

    Menghrajani, P; Klaue, K; Dubois-Arber, F; Michaud, P-A

    2005-08-01

    Few studies have attempted to investigate the nature of adolescents' and adults' conceptions and perceptions of cannabis use. Our objectives were to explore adolescent and adult perception of use and misuse of cannabis, and their opinions and beliefs about the current legal context and preventive strategies. We used focus group discussions with four categories of stakeholders: younger (12-15 year old) adolescents, older (16-19 year old) adolescents, parents of teenagers and professionals working with young people. In some areas (legal framework, role of the media, importance of early preventive interventions), we found consensual attitudes and beliefs across the four groups of participants. In all four groups, participants did not have any consensual vision of the risks of cannabis use or the definition of misuse. In the area of the prevention of cannabis use/misuse, while parents focused on the potential role of professionals and the media, thus minimizing their own educational and preventive role, professionals stressed the importance of parental control and education. Within the Swiss context, we conclude there exists an urgent need for information and clarification of the issues linked with cannabis use and misuse directed at parents and professionals. PMID:15572435

  19. Adolescent cannabis exposure interacts with mutant DISC1 to produce impaired adult emotional memory

    PubMed Central

    Ballinger, Michael D.; Saito, Atsushi; Abazyan, Bagrat; Taniguchi, Yu; Huang, Ching-Hsun; Ito, Koki; Zhu, Xiaolei; Segal, Hadar; Jaaro-Peled, Hanna; Sawa, Akira; Mackie, Ken; Pletnikov, Mikhail V.; Kamiya, Atsushi

    2015-01-01

    Cannabis is an increasingly popular and controversial drug used worldwide. Cannabis use often begins during adolescence, a highly susceptible period for environmental stimuli to alter functional and structural organization of the developing brain. Given that adolescence is a critical time for the emergence of mental illnesses before full-onset in early adulthood, it is particularly important to investigate how genetic insults and adolescent cannabis exposure interact to affect brain development and function. Here we show for the first time that a perturbation in Disrupted in Schizophrenia 1 (DISC1) exacerbates the response to adolescent exposure to delta-9-tetrahydrocannabinol (Δ9-THC), a major psychoactive ingredient of cannabis, consistent with the concept that gene-environment interactions may contribute to the pathophysiology of psychiatric conditions. We found that chronic adolescent treatment with Δ9-THC exacerbates deficits in fear-associated memory in adult mice that express a putative dominant-negative mutant of DISC1 (DN-DISC1). Synaptic expression of cannabinoid receptor 1 (CB1R) is down-regulated in the prefrontal cortex, hippocampus, and amygdala, critical brain regions for fear-associated memory, by either expression of DN-DISC1 or adolescent Δ9-THC treatment. Notably, elevation of c-Fos expression evoked by context-dependent fear memory retrieval is impaired in these brain regions in DN-DISC1 mice. We also found a synergistic reduction of c-Fos expression induced by cue-dependent fear memory retrieval in DN-DISC1 with adolescent Δ9-THC exposure. These results suggest that alteration of CB1R-mediated signaling in DN-DISC1 mice may underlie susceptibility to detrimental effects of adolescent cannabis exposure on adult behaviors. PMID:26093170

  20. Adolescent cannabis exposure interacts with mutant DISC1 to produce impaired adult emotional memory.

    PubMed

    Ballinger, Michael D; Saito, Atsushi; Abazyan, Bagrat; Taniguchi, Yu; Huang, Ching-Hsun; Ito, Koki; Zhu, Xiaolei; Segal, Hadar; Jaaro-Peled, Hanna; Sawa, Akira; Mackie, Ken; Pletnikov, Mikhail V; Kamiya, Atsushi

    2015-10-01

    Cannabis is an increasingly popular and controversial drug used worldwide. Cannabis use often begins during adolescence, a highly susceptible period for environmental stimuli to alter functional and structural organization of the developing brain. Given that adolescence is a critical time for the emergence of mental illnesses before full-onset in early adulthood, it is particularly important to investigate how genetic insults and adolescent cannabis exposure interact to affect brain development and function. Here we show for the first time that a perturbation in disrupted in schizophrenia 1 (DISC1) exacerbates the response to adolescent exposure to delta-9-tetrahydrocannabinol (Δ(9)-THC), a major psychoactive ingredient of cannabis, consistent with the concept that gene-environment interaction may contribute to the pathophysiology of psychiatric conditions. We found that chronic adolescent treatment with Δ(9)-THC exacerbates deficits in fear-associated memory in adult mice that express a putative dominant-negative mutant of DISC1 (DN-DISC1). Synaptic expression of cannabinoid receptor 1 (CB1R) is down-regulated in the prefrontal cortex, hippocampus, and amygdala, critical brain regions for fear-associated memory, by either expression of DN-DISC1 or adolescent Δ(9)-THC treatment. Notably, elevation of c-Fos expression evoked by context-dependent fear memory retrieval is impaired in these brain regions in DN-DISC1 mice. We also found a synergistic reduction of c-Fos expression induced by cue-dependent fear memory retrieval in DN-DISC1 with adolescent Δ(9)-THC exposure. These results suggest that alteration of CB1R-mediated signaling in DN-DISC1 mice may underlie susceptibility to detrimental effects of adolescent cannabis exposure on adult behaviors.

  1. Adolescent cannabis exposure interacts with mutant DISC1 to produce impaired adult emotional memory.

    PubMed

    Ballinger, Michael D; Saito, Atsushi; Abazyan, Bagrat; Taniguchi, Yu; Huang, Ching-Hsun; Ito, Koki; Zhu, Xiaolei; Segal, Hadar; Jaaro-Peled, Hanna; Sawa, Akira; Mackie, Ken; Pletnikov, Mikhail V; Kamiya, Atsushi

    2015-10-01

    Cannabis is an increasingly popular and controversial drug used worldwide. Cannabis use often begins during adolescence, a highly susceptible period for environmental stimuli to alter functional and structural organization of the developing brain. Given that adolescence is a critical time for the emergence of mental illnesses before full-onset in early adulthood, it is particularly important to investigate how genetic insults and adolescent cannabis exposure interact to affect brain development and function. Here we show for the first time that a perturbation in disrupted in schizophrenia 1 (DISC1) exacerbates the response to adolescent exposure to delta-9-tetrahydrocannabinol (Δ(9)-THC), a major psychoactive ingredient of cannabis, consistent with the concept that gene-environment interaction may contribute to the pathophysiology of psychiatric conditions. We found that chronic adolescent treatment with Δ(9)-THC exacerbates deficits in fear-associated memory in adult mice that express a putative dominant-negative mutant of DISC1 (DN-DISC1). Synaptic expression of cannabinoid receptor 1 (CB1R) is down-regulated in the prefrontal cortex, hippocampus, and amygdala, critical brain regions for fear-associated memory, by either expression of DN-DISC1 or adolescent Δ(9)-THC treatment. Notably, elevation of c-Fos expression evoked by context-dependent fear memory retrieval is impaired in these brain regions in DN-DISC1 mice. We also found a synergistic reduction of c-Fos expression induced by cue-dependent fear memory retrieval in DN-DISC1 with adolescent Δ(9)-THC exposure. These results suggest that alteration of CB1R-mediated signaling in DN-DISC1 mice may underlie susceptibility to detrimental effects of adolescent cannabis exposure on adult behaviors. PMID:26093170

  2. Cannabis and caries--does regular cannabis use increase the risk of caries in cigarette smokers?

    PubMed

    Schulz-Katterbach, Michèle; Imfeld, Thomas; Imfeld, Carola

    2009-01-01

    The use of cannabis by adolescents in Switzerland has almost doubled in the past decade. Empirical observations in private dental practices indicate that cannabis users have more carious lesions than those who do not use cannabis. The aim of this study was to investigate the hypothesis that regular cannabis use increases the risk of caries because of hyposalivation or lifestyle. Forty-three regular cannabis users were enrolled in the test group and 42 tobacco smokers were used as a negative control group. All subjects were 18-25 years old. Data were obtained using a standardized questionnaire and a clinical examination. There was no significant difference between groups in decayed and filled surfaces (DFS), saliva flow rate and plaque and gingival indices. The cannabis group had, however, significantly higher DS (decayed surface) values (p = 0.0001) and significantly lower frequencies of daily tooth brushing and dental control visits (p < 0.0001) than the control group. Additionally, the cannabis group reported a significantly higher consumption of sugar-containing beverages than the control group (p = 0.0078). To obtain more objective data relations, the DS values of male cannabis users were also compared with those of Swiss military recruits found in another study. The cannabis users had more caries on smooth surfaces than the military recruits. Although comparison with epidemiological data suggested that the prevalence of caries on smooth surfaces is elevated in cannabis users, DFS data indicated that cannabis users do not have an increased risk of caries. Lifestyle combined with short-term hyposalivation after delta-9-tetrahydrocannabinol consumption is the most probable cause of the high prevalence of caries on smooth surfaces in cannabis users. Further studies are needed to investigate the effects of cannabis use on oral health.

  3. Early Cannabis Use, Polygenic Risk Score for Schizophrenia, and Brain Maturation in Adolescence

    PubMed Central

    French, Leon; Gray, Courtney; Leonard, Gabriel; Perron, Michel; Pike, G. Bruce; Richer, Louis; Séguin, Jean R.; Veillette, Suzanne; Evans, C. John; Artiges, Eric; Banaschewski, Tobias; Bokde, Arun W. L.; Bromberg, Uli; Bruehl, Ruediger; Buchel, Christian; Cattrell, Anna; Conrod, Patricia J.; Flor, Herta; Frouin, Vincent; Gallinat, Jurgen; Garavan, Hugh; Gowland, Penny; Heinz, Andreas; Lemaitre, Herve; Martinot, Jean-Luc; Nees, Frauke; Orfanos, Dimitri Papadopoulos; Pangelinan, Melissa Marie; Poustka, Luise; Rietschel, Marcella; Smolka, Michael N.; Walter, Henrik; Whelan, Robert; Timpson, Nic J.; Schumann, Gunter; Smith, George Davey; Pausova, Zdenka; Paus, Tomáš

    2016-01-01

    IMPORTANCE Cannabis use during adolescence is known to increase the risk for schizophrenia in men. Sex differences in the dynamics of brain maturation during adolescence may be of particular importance with regard to vulnerability of the male brain to cannabis exposure. OBJECTIVE To evaluate whether the association between cannabis use and cortical maturation in adolescents is moderated by a polygenic risk score for schizophrenia. DESIGN, SETTING, AND PARTICIPANTS Observation of 3 population-based samples included initial analysis in 1024 adolescents of both sexes from the Canadian Saguenay Youth Study (SYS) and follow-up in 426 adolescents of both sexes from the IMAGEN Study from 8 European cities and 504 male youth from the Avon Longitudinal Study of Parents and Children (ALSPAC) based in England. A total of 1577 participants (aged 12–21 years; 899 [57.0%] male) had (1) information about cannabis use; (2) imaging studies of the brain; and (3) a polygenic risk score for schizophrenia across 108 genetic loci identified by the Psychiatric Genomics Consortium. Data analysis was performed from March 1 through December 31, 2014. MAIN OUTCOMES AND MEASURES Cortical thickness derived from T1-weighted magnetic resonance images. Linear regression tests were used to assess the relationships between cannabis use, cortical thickness, and risk score. RESULTS Across the 3 samples of 1574 participants, a negative association was observed between cannabis use in early adolescence and cortical thickness in male participants with a high polygenic risk score. This observation was not the case for low-risk male participants or for the low- or high-risk female participants. Thus, in SYS male participants, cannabis use interacted with risk score vis-à-vis cortical thickness (P = .009); higher scores were associated with lower thickness only in males who used cannabis. Similarly, in the IMAGEN male participants, cannabis use interacted with increased risk score vis-à-vis a change in

  4. Adolescent brain maturation, the endogenous cannabinoid system and the neurobiology of cannabis-induced schizophrenia.

    PubMed

    Bossong, Matthijs G; Niesink, Raymond J M

    2010-11-01

    Cannabis use during adolescence increases the risk of developing psychotic disorders later in life. However, the neurobiological processes underlying this relationship are unknown. This review reports the results of a literature search comprising various neurobiological disciplines, ultimately converging into a model that might explain the neurobiology of cannabis-induced schizophrenia. The article briefly reviews current insights into brain development during adolescence. In particular, the role of the excitatory neurotransmitter glutamate in experience-dependent maturation of specific cortical circuitries is examined. The review also covers recent hypotheses regarding disturbances in strengthening and pruning of synaptic connections in the prefrontal cortex, and the link with latent psychotic disorders. In the present model, cannabis-induced schizophrenia is considered to be a distortion of normal late postnatal brain maturation. Distortion of glutamatergic transmission during critical periods may disturb prefrontal neurocircuitry in specific brain areas. Our model postulates that adolescent exposure to Δ9-tetrahydrocannabinol (THC), the primary psychoactive substance in cannabis, transiently disturbs physiological control of the endogenous cannabinoid system over glutamate and GABA release. As a result, THC may adversely affect adolescent experience-dependent maturation of neural circuitries within prefrontal cortical areas. Depending on dose, exact time window and duration of exposure, this may ultimately lead to the development of psychosis or schizophrenia. The proposed model provides testable hypotheses which can be addressed in future studies, including animal experiments, reanalysis of existing epidemiological data, and prospective epidemiological studies in which the role of the dose-time-effect relationship should be central.

  5. Pharmacokinetic and pharmacodynamic profile of supratherapeutic oral doses of Δ(9) -THC in cannabis users.

    PubMed

    Lile, Joshua A; Kelly, Thomas H; Charnigo, Richard J; Stinchcomb, Audra L; Hays, Lon R

    2013-07-01

    Oral Δ(9) -tetrahydrocannabinol (Δ(9) -THC) has been evaluated as a medication for cannabis dependence, but repeated administration of acute oral doses up to 40 mg has not been effective at reducing drug-taking behavior. Larger doses might be necessary to affect cannabis use. The purpose of the present study was therefore to determine the physiological and behavioural effects of oral Δ(9) -THC at acute doses higher than those tested previously. The pharmacokinetic and pharmacodynamic profile of oral Δ(9) -THC, administered in ascending order in 15 mg increments across separate sessions, up to a maximum of 90 mg, was determined in seven cannabis users. Five subjects received all doses and two experienced untoward side effects at lower doses. Δ(9) -THC produced a constellation of effects consistent with previous clinical studies. Low cannabinoid concentrations were associated with significant effects on drug-sensitive measures, although progressively greater levels did not lead to proportionately larger drug effects. Considerable variability in Cmax and tmax was observed. Doses of oral Δ(9) -THC larger than those tested previously can be administered to individuals with a history of cannabis use, although given the pharmacokinetic variability of oral Δ(9) -THC and individual differences in sensitivity, individualized dose adjustment is needed to avoid side effects and maximize therapeutic response.

  6. Reasoning deficits among illicit drug users are associated with aspects of cannabis use.

    PubMed

    Fisk, John E; Morley, Andy M; Hadjiefthyvoulou, Florentia; Montgomery, Catharine

    2014-11-01

    Deficits in deductive reasoning have been observed among ecstasy/polydrug users. The present study seeks to investigate dose-related effects of specific drugs and whether these vary with the cognitive demands of the task. One hundred and five participants (mean age 21.33, SD 3.14; 77 females, 28 males) attempted to generate solutions for eight one-model syllogisms and one syllogism for which there was no valid conclusion. All of the one-model syllogisms generated at least one valid conclusion and six generated two valid conclusions. In these six cases, one of the conclusions was classified as common and the other as non-common. The number of valid common inferences was negatively associated with the aspects of short-term cannabis use and with measures of IQ. The outcomes observed were more than simple post-intoxication effects since cannabis use in the 10 days immediately before testing was unrelated to reasoning performance. Following adjustment for multiple comparisons, the number of non-common valid inferences was not significantly associated with any of the drug-use measures. Recent cannabis use appears to impair the processes associated with generating valid common inferences while not affecting the production of non-common inferences. It is possible, therefore, that the two types of inference may recruit different executive resources, which may differ in their susceptibility to cannabis-related effects. PMID:24723099

  7. Cannabis abuse in adolescence and the risk of psychosis: a brief review of the preclinical evidence.

    PubMed

    Rubino, T; Parolaro, D

    2014-07-01

    Epidemiological studies suggest that Cannabis use during adolescence confers an increased risk for developing psychotic symptoms later in life. However, despite their interest, the epidemiological data are not conclusive, due to their heterogeneity; thus modeling the adolescent phase in animals is useful for investigating the impact of Cannabis use on deviations of adolescent brain development that might confer a vulnerability to later psychotic disorders. Although scant, preclinical data seem to support the presence of impaired social behaviors, cognitive and sensorimotor gating deficits as well as psychotic-like signs in adult rodents after adolescent cannabinoid exposure, clearly suggesting that this exposure may trigger a complex behavioral phenotype closely resembling a schizophrenia-like disorder. Similar treatments performed at adulthood were not able to produce such phenotype, thus pointing to a vulnerability of the adolescent brain towards cannabinoid exposure. The neurobiological substrate of the adolescent vulnerability is still largely unknown and experimental studies need to elucidate the cellular and molecular mechanism underlying these effects. However, the few data available seem to suggest that heavy adolescent exposure to cannabinoids is able to modify neuronal connectivity in specific brain areas long after the end of the treatment. This is likely due to disruption of maturational events within the endocannabinoid system during adolescence that in turn impact on the correct neuronal refinement peculiar of the adolescent brain, thus leading to altered adult brain functionality and behavior.

  8. [18F]MK-9470 PET measurement of cannabinoid CB1 receptor availability in chronic cannabis users.

    PubMed

    Ceccarini, Jenny; Kuepper, Rebecca; Kemels, Dieter; van Os, Jim; Henquet, Cécile; Van Laere, Koen

    2015-03-01

    Δ(9) -Tetrahydrocannabinol, the main psychoactive component of cannabis, exerts its central effects through activation of the cerebral type 1 cannabinoid (CB1 ) receptor. Pre-clinical studies have provided evidence that chronic cannabis exposure is linked to decreased CB1 receptor expression and this is thought to be a component underlying drug tolerance and dependence. In this study, we make first use of the selective high-affinity positron emission tomography (PET) ligand [(18) F]MK-9470 to obtain in vivo measurements of cerebral CB1 receptor availability in 10 chronic cannabis users (age = 26.0 ± 4.1 years). Each patient underwent [(18) F]MK-9470 PET within the first week following the last cannabis consumption. A population of 10 age-matched healthy subjects (age = 23.0 ± 2.9 years) was used as control group. Parametric modified standardized uptake value images, reflecting CB1 receptor availability, were calculated. Statistical parametric mapping and volume-of-interest (VOI) analyses of CB1 receptor availability were performed. Compared with controls, cannabis users showed a global decrease in CB1 receptor availability (-11.7 percent). VOI-based analysis demonstrated that the CB1 receptor decrease was significant in the temporal lobe (-12.7 percent), anterior (-12.6 percent) and posterior cingulate cortex (-13.5 percent) and nucleus accumbens (-11.2 percent). Voxel-based analysis confirmed this decrease and regional pattern in CB1 receptor availability in cannabis users. These findings revealed that chronic cannabis use may alter specific regional CB1 receptor expression through neuroadaptive changes in CB1 receptor availability, opening the way for the examination of specific CB1 -cannabis addiction interactions which may predict future cannabis-related treatment outcome.

  9. From child maltreatment to adolescent cannabis abuse and dependence: A developmental cascade model

    PubMed Central

    Rogosch, Fred A.; Oshri, Assaf; Cicchetti, Dante

    2010-01-01

    A developmental cascade model tested associations among child maltreatment, internalizing and externalizing psychopathology, social competence, and cannabis abuse and dependence symptoms in a longitudinal cohort (N = 415). Nested structural equation models evaluated continuity and cross-domain influences among broad multi-informant constructs across four developmental periods: age 7 to 9, 10 to 12, 13 to 15, and 15 to 18. Results indicated significant paths from child maltreatment to early externalizing and internalizing problems and social competence, as well as to cannabis abuse and dependence (CAD) symptoms in adolescence. Youth CAD symptoms were primarily related directly to child maltreatment and externalizing problems. Childhood internalizing symptoms contributed to later childhood decreases in social competence, which predicted increases in late adolescent externalizing problems. Using a developmental psychopathology framework, results are discussed in relation to cascade and transactional effects and the interplay between problem behaviors during childhood and development of CAD symptoms during early and late adolescence. PMID:20883588

  10. Age, sex and personality in early cannabis use.

    PubMed

    Muro I Rodríguez, A

    2015-06-01

    Previous studies analysing personality and cannabis use in adult samples suggest that cannabis users show significant higher levels of impulsivity, sensation seeking and schizotypy. However, there are few studies exploring this relationship in adolescence using psychobiological models of personality. Given the relevance of identifying individual differences that lead adolescents to early cannabis use to prevent future health problems, the present study aimed to explore the relationship between age, sex, personality and early cannabis use using a psychobiological model of personality in a sample of 415 students (51.8% boys) from 12 to 18 years. Chi(2) tests showed significant higher prevalence of cannabis use in boys and in the group aged 15-18 years. Multiple analysis of variance showed significant higher scores in psychoticism, sensation seeking and in all its subscales in cannabis users group, while an interaction with age was found for extraversion and neuroticism: cannabis users scored higher than non-users in the youngest group (12-14 years) but lower in the oldest group in both dimensions. Finally, regression analysis showed that narrower traits of sensation seeking (experience seeking and disinhibition) were the most associated to early cannabis use. Results are discussed in terms of early cannabis users' personality profiles and in terms of the self-medication theory.

  11. Clustering of smoking, alcohol drinking and cannabis use in adolescents in a rapidly developing country

    PubMed Central

    Faeh, David; Viswanathan, Bharathi; Chiolero, Arnaud; Warren, Wick; Bovet, Pascal

    2006-01-01

    Background Smoking, alcohol drinking and cannabis use ("risk behaviors") are often initiated at a young age but few epidemiological studies have assessed their joined prevalence in children in developing countries. This study aims at examining the joint prevalence of these behaviors in adolescents in the Seychelles, a rapidly developing country in the Indian Ocean. Methods Cross-sectional survey in a representative sample of secondary school students using an anonymous self-administered questionnaire (Global Youth Tobacco Survey). The questionnaire was completed by 1,321 (92%) of 1,442 eligible students aged 11 to 17 years. Main variables of interest included smoking cigarettes on ≥1 day in the past 30 days; drinking any alcohol beverage on ≥1 day in the past 30 days and using cannabis at least once in the past 12 months. Results In boys and girls, respectively, prevalence (95% CI) was 30% (26–34)/21% (18–25) for smoking, 49% (45–54)/48% (43–52) for drinking, and 17% (15–20)/8% (6–10) for cannabis use. The prevalence of all these behaviors increased with age. Smokers were two times more likely than non-smokers to drink and nine times more likely to use cannabis. Drinkers were three times more likely than non-drinkers to smoke or to use cannabis. Comparison of observed versus expected frequencies of combination categories demonstrated clustering of these risk behaviors in students (P < 0.001). Conclusion Smoking, drinking and cannabis use were common and clustered among adolescents of a rapidly developing country. These findings stress the need for early and integrated prevention programs. PMID:16803621

  12. The mediation role of licit drugs in the influence of socializing on cannabis use among adolescents: A quantitative approach.

    PubMed

    Mayet, Aurélie; Legleye, Stéphane; Chau, Nearkasen; Falissard, Bruno

    2010-10-01

    Licit substance use could be an early stage leading on to cannabis use. The aim of the study was to test a hypothetical sequential process leading from socializing to cannabis use so as to evaluate the mediator role of tobacco and alcohol. Data was derived from a French nationwide survey carried out in 2005 involving 29,393 teenagers aged 17. The analysis used structural equation modelling. The sequence tested was: socializing with friends-tobacco/alcohol use-cannabis use-cannabis use disorders (CUD). Tobacco and alcohol consumptions appeared to be similarly influenced by the time spent with friends. However, tobacco mediation explained 57% of the sequence leading to cannabis use and 61% of the sequence leading to CUD, while the role of alcohol was weaker, at around 13%. Our results underline the effect of peer influence, in the course of night-out socializing, on substance use among adolescents, and the importance of tobacco mediation in the process leading to cannabis use and misuse. This suggests that prevention in places frequented by adolescents should primarily target tobacco consumption, which explains the largest part of cannabis use variance. However, processes linking substance uses seem to be more complex, with the existence of reverse pathways from cannabis to licit drugs. Thus, the gateway effects of tobacco and alcohol require further exploration in relation to simultaneous polysubstance use.

  13. Long term marijuana users seeking medical cannabis in California (2001–2007): demographics, social characteristics, patterns of cannabis and other drug use of 4117 applicants

    PubMed Central

    O'Connell, Thomas J; Bou-Matar, Ché B

    2007-01-01

    Background Cannabis (marijuana) had been used for medicinal purposes for millennia. Cannabinoid agonists are now attracting growing interest and there is also evidence that botanical cannabis is being used as self-medication for stress and anxiety as well as adjunctive therapy by the seriously ill and by patients with terminal illnesses. California became the first state to authorize medicinal use of cannabis in 1996, and it was recently estimated that between 250,000 and 350,000 Californians may now possess the physician's recommendation required to use it medically. More limited medical use has also been approved in 12 additional states and new initiatives are being considered in others. Despite that evidence of increasing public acceptance of "medical" use, a definitional problem remains and all use for any purpose is still prohibited by federal law. Results California's 1996 initiative allowed cannabis to be recommended, not only for serious illnesses, but also "for any other illness for which marijuana provides relief," thus maximally broadening the range of allowable indications. In effect, the range of conditions now being treated with federally illegal cannabis, the modes in which it is being used, and the demographics of the population using it became potentially discoverable through the required screening of applicants. This report examines the demographic profiles and other selected characteristics of 4117 California marijuana users (62% from the Greater Bay Area) who applied for medical recommendations between late 2001 and mid 2007. Conclusion This study yielded a somewhat unexpected profile of a hitherto hidden population of users of America's most popular illegal drug. It also raises questions about some of the basic assumptions held by both proponents and opponents of current policy. PMID:17980043

  14. Cannabis and tobacco use: where are the boundaries? A qualitative study on cannabis consumption modes among adolescents.

    PubMed

    Akre, Christina; Michaud, Pierre-André; Berchtold, André; Suris, Joan-Carles

    2010-02-01

    The purpose of this article is to identify tobacco and cannabis co-consumptions and consumers' perceptions of each substance. A qualitative research including 22 youths (14 males) aged 15-21 years in seven individual interviews and five focus groups. Discussions were recorded, transcribed verbatim and transferred to Atlas.ti software for narrative analysis. The main consumption mode is cannabis cigarettes which always mix cannabis and tobacco. Participants perceive cannabis much more positively than tobacco, which is considered unnatural, harmful and addictive. Future consumption forecasts thus more often exclude tobacco smoking than cannabis consumption. A substitution phenomenon often takes place between both substances. Given the co-consumption of tobacco and cannabis, in helping youths quit or decrease their consumptions, both substances should be taken into account in a global approach. Cannabis consumers should be made aware of their tobacco use while consuming cannabis and the risk of inducing nicotine addiction through cannabis use, despite the perceived disconnect between the two substances. Prevention programs should correct made-up ideas about cannabis consumption and convey a clear message about its harmful consequences. Our findings support the growing evidence which suggests that nicotine dependence and cigarette smoking may be induced by cannabis consumption.

  15. Modulation of brain structure by catechol-O-methyltransferase Val(158) Met polymorphism in chronic cannabis users.

    PubMed

    Batalla, Albert; Soriano-Mas, Carles; López-Solà, Marina; Torrens, Marta; Crippa, José A; Bhattacharyya, Sagnik; Blanco-Hinojo, Laura; Fagundo, Ana B; Harrison, Ben J; Nogué, Santiago; de la Torre, Rafael; Farré, Magí; Pujol, Jesús; Martín-Santos, Rocío

    2014-07-01

    Neuroimaging studies have shown that chronic consumption of cannabis may result in alterations in brain morphology. Recent work focusing on the relationship between brain structure and the catechol-O-methyltransferase (COMT) gene polymorphism suggests that functional COMT variants may affect brain volume in healthy individuals and in schizophrenia patients. We measured the influence of COMT genotype on the volume of four key regions: the prefrontal cortex, neostriatum (caudate-putamen), anterior cingulate cortex and hippocampus-amygdala complex, in chronic early-onset cannabis users and healthy control subjects. We selected 29 chronic cannabis users who began using cannabis before 16 years of age and matched them to 28 healthy volunteers in terms of age, educational level and IQ. Participants were male, Caucasians aged between 18 and 30 years. All were assessed by a structured psychiatric interview (PRISM) to exclude any lifetime Axis-I disorder according to Diagnostic and Statistical Manual for Mental Disorders-Fourth Edition. COMT genotyping was performed and structural magnetic resonance imaging data was analyzed by voxel-based morphometry. The results showed that the COMT polymorphism influenced the volume of the bilateral ventral caudate nucleus in both groups, but in an opposite direction: more copies of val allele led to lesser volume in chronic cannabis users and more volume in controls. The opposite pattern was found in left amygdala. There were no effects of COMT genotype on volumes of the whole brain or the other selected regions. Our findings support recent reports of neuroanatomical changes associated with cannabis use and, for the first time, reveal that these changes may be influenced by the COMT genotype.

  16. Cannabis use and quality of life of adolescents and young adults: findings from an Australian birth cohort.

    PubMed

    Fischer, Jane A; Clavarino, Alexandra M; Plotnikova, Maria; Najman, Jackob M

    2015-01-01

    Cannabis is generally used to enhance mood (quality of life), but it is not known whether it has this effect in the medium to longer term. Little is currently known about the temporal sequence between cannabis use and the quality of life (QOL). Data are taken from a prospective longitudinal study of pregnant women recruited at their first antenatal visit in Brisbane, Australia. Offspring data from the follow-ups with 14-year-olds and 21-year-olds are used here. Indicators of QOL, happiness, and satisfaction at 14 years are considered as predictors of subsequent cannabis use. The association between cannabis use and QOL at 21 years, adjusting for prior QOL (14 years), is also examined. Socio-demographic characteristics were included as potential confounders relevant to QOL assessments. In this cohort, lower QOL in the early teenage years predicted subsequent onset of cannabis use in young adulthood. After adjustment for socio-demographic characteristics and for QOL pre-cannabis use, participants who used cannabis more frequently had a lower QOL at the 21-years follow-up. Frequent use of cannabis does not appear to enhance the user's QOL and appears to be associated with a reduced QOL into young adulthood. PMID:25950590

  17. Cannabis use and quality of life of adolescents and young adults: findings from an Australian birth cohort.

    PubMed

    Fischer, Jane A; Clavarino, Alexandra M; Plotnikova, Maria; Najman, Jackob M

    2015-01-01

    Cannabis is generally used to enhance mood (quality of life), but it is not known whether it has this effect in the medium to longer term. Little is currently known about the temporal sequence between cannabis use and the quality of life (QOL). Data are taken from a prospective longitudinal study of pregnant women recruited at their first antenatal visit in Brisbane, Australia. Offspring data from the follow-ups with 14-year-olds and 21-year-olds are used here. Indicators of QOL, happiness, and satisfaction at 14 years are considered as predictors of subsequent cannabis use. The association between cannabis use and QOL at 21 years, adjusting for prior QOL (14 years), is also examined. Socio-demographic characteristics were included as potential confounders relevant to QOL assessments. In this cohort, lower QOL in the early teenage years predicted subsequent onset of cannabis use in young adulthood. After adjustment for socio-demographic characteristics and for QOL pre-cannabis use, participants who used cannabis more frequently had a lower QOL at the 21-years follow-up. Frequent use of cannabis does not appear to enhance the user's QOL and appears to be associated with a reduced QOL into young adulthood.

  18. [Clinical characteristics of cannabis-induced schizophrenia spectrum disorder].

    PubMed

    Makkos, Zoltán; Fejes, Lilla; Inczédy-Farkas, Gabriella; Kassai-Farkas, Akos; Faludi, Gábor; Lazáry, Judit

    2011-09-01

    Marijuana (cannabis) is the most commonly abused drug by adolescents and young adults and also by people with schizophrenia or other psychotic disorders. An increasing number of studies suggest that regular cannabis users can show psychotic episodes similar to schizophrenic disorders but it still unclear if cannabis induced psychotic disorder is a distinct entity requiring special therapy or regular cannabis use consequently leads to schizophrenia. Therefore, we retrospectively compared psychotic patients with and without cannabis use by clinical profile. Clinical data of 85 patients with schizophrenia spectrum disorder were analyzed retrospectively. Cannabis use was not reported by 43 persons (Cnbs0 subgroup) and 42 patients used regularly cannabis during at least 1 year (Cnbs1 subgroup). Clinical data were collected from electronic medical documentation of patients concerning anamnesis, family history, socio-demographic condition, symptoms and psychiatric state, acute and long-term therapies. Men were over-represented in the cannabis abuser group while mean age was lower among them compared to the Cnbs0 subgroup. Prevalence of suicidal attempts was increased in men without cannabis use. Patients without cannabis use spent more time in hospital and smoking was more frequent among them. Positive and negative symptoms and family history did not differ significantly between the two subgroups. Dosage, intensity and length of pharmacotherapy was different between the two subgroups. These results revealed that certain clinical aspects were different in case of cannabis-related schizophrenia spectrum disorder compared to schizophrenia.

  19. The choice of screening instrument matters: the case of problematic cannabis use screening in spanish population of adolescents.

    PubMed

    Thanki, Danica; Domingo-Salvany, Antónia; Barrio Anta, Gregorio; Sánchez Mañez, Amparo; Llorens Aleixandre, Noelia; Suelves, Josep Maria; Brime Beteta, Begoña; Vicente, Julián

    2013-01-01

    The aim of this study was to examine the feasibility of problem cannabis use screening instruments administration within wide school surveys, their psychometric properties, overlaps, and relationships with other variables. Students from 7 Spanish regions, aged 14-18, who attended secondary schools were sampled by two-stage cluster sampling (net sample 14,589). Standardized, anonymous questionnaire including DSM-IV cannabis abuse criteria, Cannabis Abuse Screening Test (CAST), and Severity of Dependence Scale (SDS) was self-completed with paper and pencil in the selected classrooms. Data was analysed using classical psychometric theory, bivariate tests, and multinomial logistic regression analysis. Not responding to instruments' items (10.5-12.3%) was associated with reporting less frequent cannabis use. The instruments overlapped partially, with 16.1% of positives being positive on all three. SDS was more likely to identify younger users with lower frequency of use who thought habitual cannabis use posed a considerable problem. CAST positivity was associated with frequent cannabis use and related problems. It is feasible to use short psychometric scales in wide school surveys, but one must carefully choose the screening instrument, as different instruments identify different groups of users. These may correspond to different types of problematic cannabis use; however, measurement bias seems to play a role too. PMID:25969832

  20. The Choice of Screening Instrument Matters: The Case of Problematic Cannabis Use Screening in Spanish Population of Adolescents

    PubMed Central

    Domingo-Salvany, Antónia; Barrio Anta, Gregorio; Sánchez Mañez, Amparo; Llorens Aleixandre, Noelia; Brime Beteta, Begoña; Vicente, Julián

    2013-01-01

    The aim of this study was to examine the feasibility of problem cannabis use screening instruments administration within wide school surveys, their psychometric properties, overlaps, and relationships with other variables. Students from 7 Spanish regions, aged 14–18, who attended secondary schools were sampled by two-stage cluster sampling (net sample 14,589). Standardized, anonymous questionnaire including DSM-IV cannabis abuse criteria, Cannabis Abuse Screening Test (CAST), and Severity of Dependence Scale (SDS) was self-completed with paper and pencil in the selected classrooms. Data was analysed using classical psychometric theory, bivariate tests, and multinomial logistic regression analysis. Not responding to instruments' items (10.5–12.3%) was associated with reporting less frequent cannabis use. The instruments overlapped partially, with 16.1% of positives being positive on all three. SDS was more likely to identify younger users with lower frequency of use who thought habitual cannabis use posed a considerable problem. CAST positivity was associated with frequent cannabis use and related problems. It is feasible to use short psychometric scales in wide school surveys, but one must carefully choose the screening instrument, as different instruments identify different groups of users. These may correspond to different types of problematic cannabis use; however, measurement bias seems to play a role too. PMID:25969832

  1. A Web-Based Self-Help Intervention With and Without Chat Counseling to Reduce Cannabis Use in Problematic Cannabis Users: Three-Arm Randomized Controlled Trial

    PubMed Central

    Wenger, Andreas; Berg, Oliver; Beck, Thilo; Stark, Lars; Buehler, Eveline; Haug, Severin

    2015-01-01

    Background After alcohol and tobacco, cannabis is the most widely used psychoactive substance in many countries worldwide. Although approximately one in ten users develops serious problems of dependency, only a minority attend outpatient addiction counseling centers. A Web-based intervention could potentially reach those users who hesitate to approach such treatment centers. Objective To test the efficacy of a Web-based self-help intervention with and without chat counseling—Can Reduce—in reducing the cannabis use of problematic cannabis users as an alternative to outpatient treatment services. Methods Altogether, 436 participants were recruited by various online and offline media for the Web-based trial. A total of 308 of these were eligible for study participation and were randomly allocated in an unblinded manner to either self-help with chat (n=114), self-help without chat (n=101), or a waiting list control group (n=93). The fully automated self-help intervention consisted of eight modules designed to reduce cannabis use, and was based on the principles of motivational interviewing, self-control practices, and methods of cognitive behavioral therapy. Additional individual chat counseling sessions were based on the same therapeutic principles. The sessions were conducted by trained counselors and addressed participants' personal problems. The main outcomes were the frequency (number of days) and quantity of cannabis use (number of standardized joints) per week, as entered into the consumption diary at baseline and at the 3-month follow-up. Secondary outcomes included self-reported symptoms of cannabis use disorder, severity of cannabis dependence, risky alcohol use, and mental health symptoms. Intervention participation and retention were extracted from the user progress data and the consumption diary, respectively. Results Can Reduce participants were older (U=2.296, P=.02) and reported a greater number of cannabis use days at baseline than patients who

  2. Cannabis Use Is Quantitatively Associated with Nucleus Accumbens and Amygdala Abnormalities in Young Adult Recreational Users

    PubMed Central

    Gilman, Jodi M.; Kuster, John K.; Lee, Sang; Lee, Myung Joo; Kim, Byoung Woo; Makris, Nikos; van der Kouwe, Andre; Blood, Anne J.

    2014-01-01

    Marijuana is the most commonly used illicit drug in the United States, but little is known about its effects on the human brain, particularly on reward/aversion regions implicated in addiction, such as the nucleus accumbens and amygdala. Animal studies show structural changes in brain regions such as the nucleus accumbens after exposure to Δ9-tetrahydrocannabinol, but less is known about cannabis use and brain morphometry in these regions in humans. We collected high-resolution MRI scans on young adult recreational marijuana users and nonusing controls and conducted three independent analyses of morphometry in these structures: (1) gray matter density using voxel-based morphometry, (2) volume (total brain and regional volumes), and (3) shape (surface morphometry). Gray matter density analyses revealed greater gray matter density in marijuana users than in control participants in the left nucleus accumbens extending to subcallosal cortex, hypothalamus, sublenticular extended amygdala, and left amygdala, even after controlling for age, sex, alcohol use, and cigarette smoking. Trend-level effects were observed for a volume increase in the left nucleus accumbens only. Significant shape differences were detected in the left nucleus accumbens and right amygdala. The left nucleus accumbens showed salient exposure-dependent alterations across all three measures and an altered multimodal relationship across measures in the marijuana group. These data suggest that marijuana exposure, even in young recreational users, is associated with exposure-dependent alterations of the neural matrix of core reward structures and is consistent with animal studies of changes in dendritic arborization. PMID:24741043

  3. Are IQ and educational outcomes in teenagers related to their cannabis use? A prospective cohort study.

    PubMed

    Mokrysz, C; Landy, R; Gage, S H; Munafò, M R; Roiser, J P; Curran, H V

    2016-02-01

    There is much debate about the impact of adolescent cannabis use on intellectual and educational outcomes. We investigated associations between adolescent cannabis use and IQ and educational attainment in a sample of 2235 teenagers from the Avon Longitudinal Study of Parents and Children. By the age of 15, 24% reported having tried cannabis at least once. A series of nested linear regressions was employed, adjusted hierarchically by pre-exposure ability and potential confounds (e.g. cigarette and alcohol use, childhood mental-health symptoms and behavioural problems), to test the relationships between cumulative cannabis use and IQ at the age of 15 and educational performance at the age of 16. After full adjustment, those who had used cannabis ⩾ 50 times did not differ from never-users on either IQ or educational performance. Adjusting for group differences in cigarette smoking dramatically attenuated the associations between cannabis use and both outcomes, and further analyses demonstrated robust associations between cigarette use and educational outcomes, even with cannabis users excluded. These findings suggest that adolescent cannabis use is not associated with IQ or educational performance once adjustment is made for potential confounds, in particular adolescent cigarette use. Modest cannabis use in teenagers may have less cognitive impact than epidemiological surveys of older cohorts have previously suggested.

  4. Are IQ and educational outcomes in teenagers related to their cannabis use? A prospective cohort study

    PubMed Central

    Mokrysz, C; Landy, R; Gage, SH; Munafò, MR; Roiser, JP; Curran, HV

    2016-01-01

    There is much debate about the impact of adolescent cannabis use on intellectual and educational outcomes. We investigated associations between adolescent cannabis use and IQ and educational attainment in a sample of 2235 teenagers from the Avon Longitudinal Study of Parents and Children. By the age of 15, 24% reported having tried cannabis at least once. A series of nested linear regressions was employed, adjusted hierarchically by pre-exposure ability and potential confounds (e.g. cigarette and alcohol use, childhood mental-health symptoms and behavioural problems), to test the relationships between cumulative cannabis use and IQ at the age of 15 and educational performance at the age of 16. After full adjustment, those who had used cannabis ⩾50 times did not differ from never-users on either IQ or educational performance. Adjusting for group differences in cigarette smoking dramatically attenuated the associations between cannabis use and both outcomes, and further analyses demonstrated robust associations between cigarette use and educational outcomes, even with cannabis users excluded. These findings suggest that adolescent cannabis use is not associated with IQ or educational performance once adjustment is made for potential confounds, in particular adolescent cigarette use. Modest cannabis use in teenagers may have less cognitive impact than epidemiological surveys of older cohorts have previously suggested. PMID:26739345

  5. Fitness to drive and cannabis: validation of two blood THCCOOH thresholds to distinguish occasional users from heavy smokers.

    PubMed

    Fabritius, Marie; Augsburger, Marc; Chtioui, Haithem; Favrat, Bernard; Giroud, Christian

    2014-09-01

    Many studies based on either an experimental or an epidemiological approach, have shown that the ability to drive is impaired when the driver is under the influence of cannabis. Baseline performances of heavy users remain impaired even after several weeks of abstinence. Symptoms of cannabis abuse and dependence are generally considered incompatible with safe driving. Recently, it has been shown that traffic safety can be increased by reporting the long-term unfit drivers to the driver licensing authorities and referring the cases for further medical assessment. Evaluation of the frequency of cannabis use is a prerequisite for a reliable medical assessment of the fitness to drive. In a previous paper we advocated the use of two thresholds based on 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCCOOH) concentration in whole blood to help to distinguish occasional cannabis users (≤3 μg/L) from heavy regular smokers (≥40 μg/L). These criteria were established on the basis of results obtained in a controlled cannabis smoking study with placebo, carried out with two groups of young male volunteers; the first group was characterized by a heavy use (≥10 joints/month) while the second group was made up of occasional users smoking at most 1 joint/week. However, to date, these cutoffs have not been adequately assessed under real conditions. Their validity can now be evaluated and confirmed with 146 traffic offenders' real cases in which the whole blood cannabinoid concentrations and the frequency of cannabis use are known. The two thresholds were not challenged by the presence of ethanol (40% of cases) and of other therapeutic and illegal drugs (24%). Thus, we propose the following procedure that can be very useful in the Swiss context but also in other countries with similar traffic policies: if the whole blood THCCOOH concentration is higher than 40 μg/L, traffic offenders must be directed first and foremost toward medical assessment of their fitness to drive. This

  6. Treatment of Adolescent Marijuana Abuse: A Randomized Clinical Trial. Presentation 1: Structure of the Cannabis Youth Treatment Study.

    ERIC Educational Resources Information Center

    Titus, Janet C.; Dennis, Michael L.; Diamond, Guy; Godley, Susan H.; Babor, Thomas; Donaldson, Jean; Herrell, James; Tims, Frank; Webb, Charles

    The Cannabis Youth Treatment (CYT) study is a multi-site randomized field experiment examining five outpatient treatment protocols for adolescents who abuse or are dependent on marijuana. The purpose of the CYT project is twofold: (a) to test the relative clinical effectiveness and cost-effectiveness of five promising interventions targeted at…

  7. Cannabis Use and Memory Brain Function in Adolescent Boys: A Cross-Sectional Multicenter Functional Magnetic Resonance Imaging Study

    ERIC Educational Resources Information Center

    Jager, Gerry; Block, Robert I.; Luijten, Maartje; Ramsey, Nick F.

    2010-01-01

    Objective: Early-onset cannabis use has been associated with later use/abuse, mental health problems (psychosis, depression), and abnormal development of cognition and brain function. During adolescence, ongoing neurodevelopmental maturation and experience shape the neural circuitry underlying complex cognitive functions such as memory and…

  8. Classification and Short-Term Course of DSM-IV Cannabis, Hallucinogen, Cocaine, and Opioid Disorders in Treated Adolescents

    ERIC Educational Resources Information Center

    Chung, Tammy; Martin, Christoper S.

    2005-01-01

    This study examined the latent class structure of Diagnostic and Statistical Manual of Mental Disorders (text rev.; DSM-IV; American Psychiatric Association, 2000) symptoms used to diagnose cannabis, hallucinogen, cocaine, and opiate disorders among 501 adolescents recruited from addictions treatment. Latent class results were compared with the…

  9. Methamphetamine and cannabis abuse in adolescence: a quasi-experimental study on specific and long-term neurocognitive effects

    PubMed Central

    Cuzen, Natalie L; Koopowitz, Sheri-Michelle; Ferrett, Helen L; Stein, Dan J; Yurgelun-Todd, Deborah

    2015-01-01

    Objectives Methamphetamine abuse affects brain structure and function. Although methamphetamine and cannabis are commonly abused together, few studies have investigated the differential neurocognitive consequences of methamphetamine abuse with or without cannabis. Furthermore, the effects of drug use on the developing adolescent brain remain poorly understood. We compared neurocognitive function between adolescents with ‘pure’ methamphetamine abuse, those with comorbid methamphetamine and cannabis abuse, and healthy controls at baseline and follow-up. Methods Individuals residing in the greater Cape Town region, between the ages of 13 and 18 years, were recruited into either Methamphetamine only group (Meth-only; n=10), Methamphetamine and cannabis group (Meth-cann; n=10) or healthy control (n=20) groups using a quasi-experimental design. All participants underwent a comprehensive neurocognitive assessment. Substance-use variables and psychiatric symptom counts were also recorded. A portion of the Meth-only and control participants completed 12-month follow-up assessments. Results While the Meth-cann group demonstrated widespread neurocognitive deficits at baseline, these deficits were restricted to the self-monitoring domain in the Meth-only group at baseline and at follow-up. Conclusions Methamphetamine abuse with cannabis abuse is associated with significantly more neurocognitive impairment than methamphetamine abuse alone, and such deficits may be enduring. PMID:25636791

  10. The reinforcing, self-reported performance and physiological effects of Delta9-tetrahydrocannabinol, triazolam, hydromorphone, and methylphenidate in cannabis users.

    PubMed

    Lile, Joshua A; Kelly, Thomas H; Hays, Lon R

    2010-02-01

    The use of illicit prescription drugs is common in cannabis users; however, the effects of few psychoactive drugs have been characterized in this population. In this study, Delta-tetrahydrocannabinol (i.e. Delta-THC), triazolam, hydromorphone, and methylphenidate were administered to cannabis users (n=8). Subjects completed the multiple-choice procedure to assess drug reinforcement, as well as self-report questionnaires and performance tasks; physiological assessments were also conducted. Only Delta-THC increased the crossover point on the multiple-choice procedure, but all of the drugs increased ratings on one or more 'positive' drug-effect questionnaire items, as well as items specific for each drug. Triazolam produced the most robust performance impairment, except on a time reproduction task, which was impacted to a greater degree by Delta-THC. Delta-THC elevated heart rate and decreased temperature, triazolam increased heart rate, methylphenidate elevated all cardiovascular indices, and hydromorphone reduced respiration. The effects of the drugs tested in this study were generally consistent with their known pharmacology, although minimal responses to hydromorphone were observed. Future research to directly compare the effects of different psychoactive drugs in cannabis users and nonusers would be useful for identifying potential differences in drug effects as a function of use history. PMID:19949319

  11. Substance Use and Depression Symptomatology: Measurement Invariance of the Beck Depression Inventory (BDI-II) among Non-Users and Frequent-Users of Alcohol, Nicotine and Cannabis

    PubMed Central

    Moore, Ashlee A.; Neale, Michael C.; Silberg, Judy L.; Verhulst, Brad

    2016-01-01

    Depression is a highly heterogeneous condition, and identifying how symptoms present in various groups may greatly increase our understanding of its etiology. Importantly, Major Depressive Disorder is strongly linked with Substance Use Disorders, which may ameliorate or exacerbate specific depression symptoms. It is therefore quite plausible that depression may present with different symptom profiles depending on an individual’s substance use status. Given these observations, it is important to examine the underlying construct of depression in groups of substance users compared to non-users. In this study we use a non-clinical sample to examine the measurement structure of the Beck Depression Inventory (BDI-II) in non-users and frequent-users of various substances. Specifically, measurement invariance was examined across those who do vs. do not use alcohol, nicotine, and cannabis. Results indicate strict factorial invariance across non-users and frequent-users of alcohol and cannabis, and metric invariance across non-users and frequent-users of nicotine. This implies that the factor structure of the BDI-II is similar across all substance use groups PMID:27046165

  12. Substance Use and Depression Symptomatology: Measurement Invariance of the Beck Depression Inventory (BDI-II) among Non-Users and Frequent-Users of Alcohol, Nicotine and Cannabis.

    PubMed

    Moore, Ashlee A; Neale, Michael C; Silberg, Judy L; Verhulst, Brad

    2016-01-01

    Depression is a highly heterogeneous condition, and identifying how symptoms present in various groups may greatly increase our understanding of its etiology. Importantly, Major Depressive Disorder is strongly linked with Substance Use Disorders, which may ameliorate or exacerbate specific depression symptoms. It is therefore quite plausible that depression may present with different symptom profiles depending on an individual's substance use status. Given these observations, it is important to examine the underlying construct of depression in groups of substance users compared to non-users. In this study we use a non-clinical sample to examine the measurement structure of the Beck Depression Inventory (BDI-II) in non-users and frequent-users of various substances. Specifically, measurement invariance was examined across those who do vs. do not use alcohol, nicotine, and cannabis. Results indicate strict factorial invariance across non-users and frequent-users of alcohol and cannabis, and metric invariance across non-users and frequent-users of nicotine. This implies that the factor structure of the BDI-II is similar across all substance use groups. PMID:27046165

  13. Structural Network Topology Revealed by White Matter Tractography in Cannabis Users: A Graph Theoretical Analysis

    PubMed Central

    Kim, Dae-Jin; Skosnik, Patrick D.; Cheng, Hu; Pruce, Ben J.; Brumbaugh, Margaret S.; Vollmer, Jennifer M.; Hetrick, William P.; O'Donnell, Brian F.; Sporns, Olaf; Puce, Aina

    2011-01-01

    Abstract Endocannabinoid receptors modulate synaptic plasticity in the brain and may therefore impact cortical connectivity not only during development but also in response to substance abuse in later life. Such alterations may not be evident in volumetric measures utilized in brain imaging, but could affect the local and global organization of brain networks. To test this hypothesis, we used a novel computational approach to estimate network measures of structural brain connectivity derived from diffusion tensor imaging (DTI) and white matter tractography. Twelve adult cannabis (CB) users and 13 healthy subjects were evaluated using a graph theoretic analysis of both global and local brain network properties. Structural brain networks in both CB subjects and controls exhibited robust small-world network attributes in both groups. However, CB subjects showed significantly decreased global network efficiency and significantly increased clustering coefficients (degree to which nodes tend to cluster around individual nodes). CB subjects also exhibited altered patterns of local network organization in the cingulate region. Among all subjects, schizotypal and impulsive personality characteristics correlated with global efficiency but not with the clustering coefficient. Our data indicate that structural brain networks in CB subjects are less efficiently integrated and exhibit altered regional connectivity. These differences in network properties may reflect physiological processes secondary to substance abuse-induced synaptic plasticity, or differences in brain organization that increase vulnerability to substance use. PMID:22432904

  14. Neural Mechanisms of Risky Decision-Making and Reward Response in Adolescent Onset Cannabis Use Disorder

    PubMed Central

    De Bellis, Michael D.; Wang, Lihong; Bergman, Sara R.; Yaxley, Richard H.; Hooper, Stephen R.; Huettel, Scott A.

    2013-01-01

    Background Neural mechanisms of decision-making and reward response in adolescent cannabis use disorder (CUD) are underexplored. Methods Three groups of male adolescents were studied: CUD in full remission (n=15); controls with psychopathology without substance use disorder history(n=23); and healthy controls(n=18). We investigated neural processing of decision-making and reward under conditions of varying risk and uncertainty with the Decision-Reward Uncertainty Task while participants were scanned using functional magnetic resonance imaging. Results Abstinent adolescents with CUD compared to controls with psychopathology showed hyperactivation in one cluster that spanned left superior parietal lobule/left lateral occipital cortex/precuneus while making risky decisions that involved uncertainty, and hypoactivation in left orbitofrontal cortex to rewarded outcomes compared to no-reward after making risky decisions. Post-hoc region of interest analyses revealed that both control groups significantly differed from the CUD group (but not from each other) during both the decision-making and reward outcome phase of the Decision-Reward Uncertainty Task. In the CUD group, orbitofrontal activations to reward significantly and negatively correlated with total number of individual drug classes the CUD patients experimented with prior to treatment. CUD duration significantly and negatively correlated with orbitofrontal activations to no-reward. Conclusions The adolescent CUD group demonstrated distinctly different activation patterns during risky decision-making and reward processing (after risky decision-making) compared to both the controls with psychopathology and healthy control groups. These findings suggest that neural differences in risky decision-making and reward processes are present in adolescent addiction, persist after remission from first CUD treatment, and may contribute to vulnerability for adolescent addiction. PMID:23773952

  15. Quantification of the influence of friends and antisocial behaviour in adolescent consumption of cannabis using the ZINB model and data mining.

    PubMed

    Gervilla, Elena; Cajal, Berta; Palmer, Alfonso

    2011-04-01

    Cannabis is the most consumed illegal drug in Europe and its repercussions are more important when taken up at an early age. The aim of this study is to analyse and quantify the predictive value of different personal, family and environmental variables on the consumption of cannabis in adolescence. The sample is made up of 9284 adolescents (47.1% boys and 52.9% girls) with an average age of 15.59 years (SE=1.17). The ZINB model highlights, as factors that increase the number of joints consumed per week, consumption by the peer group, nights out during the week, gender, the production of forbidden behaviour and the use of other substances, whereas the risk factors for the consumption of cannabis are consumption by friends, ease of access, production of forbidden behaviour and the use of other substances. Association rules highlight the relationship between cannabis consumption, ease of access, production of forbidden behaviour and tobacco consumption. Finally, decision trees enable us to predict cannabis consumption as well as the number of joints an adolescent will consume per week based on the production of forbidden behaviour, consumption of other substances and number of friends who consume cannabis. The results of this work have practical implications concerning the prevention of cannabis consumption in an adolescent population.

  16. Decrease in adolescent cannabis use from 2002 to 2006 and links to evenings out with friends in 31 European and North America countries and regions

    PubMed Central

    Kuntsche, Emmanuel; Simons-Morton, Bruce; Fotiou, Anastasios; ter Bogt, Tom; Kokkevi, Anna

    2008-01-01

    Objective: To compare adolescent cannabis use between 2002 and 2006 and to investigate links to the frequency of evenings spent out with friends. Design and setting: National representative samples of 31 mostly European and North American countries and regions as part of the Health Behaviour in School-Aged Children (HBSC) study were analyzed by means of χ2-tests, t-test, and logistic regression analysis. Participants: 93,297 15-year old students. Outcome measure: Cannabis use in the last 12 month in relation to the mean frequency of evenings out with friends per week. Results: A decrease in the prevalence of cannabis use was found in most of the 31 participating countries and regions. The most marked decreases were found in England, Portugal, Switzerland, Slovenia, and Canada. Increases occurred only in Estonia, Lithuania, Malta, and among Russian girls. The more frequently adolescents reported going out with their friends in the evenings the more likely they were to report using cannabis. This link was consistent for boys and girls and across survey years. Across countries, changes in the mean frequency of evenings spent out were strongly linked to changes in cannabis use prevalence. Conclusion: The findings are consistent with the hypothesis that by going out less frequently in the evenings with friends adolescents had fewer opportunities to obtain and use cannabis. Future research is needed to learn more about the nature of evenings out with friends and related factors that might explain changes in adolescent cannabis use over time. PMID:19188643

  17. Cannabis and Tobacco Use: Where Are the Boundaries? A Qualitative Study on Cannabis Consumption Modes among Adolescents

    ERIC Educational Resources Information Center

    Akre, Christina; Michaud, Pierre-Andre; Berchtold, Andre; Suris, Joan-Carles

    2010-01-01

    The purpose of this article is to identify tobacco and cannabis co-consumptions and consumers' perceptions of each substance. A qualitative research including 22 youths (14 males) aged 15-21 years in seven individual interviews and five focus groups. Discussions were recorded, transcribed verbatim and transferred to Atlas.ti software for narrative…

  18. Cortical thickness in adolescent marijuana and alcohol users: A three-year prospective study from adolescence to young adulthood.

    PubMed

    Jacobus, Joanna; Squeglia, Lindsay M; Meruelo, Alejandro D; Castro, Norma; Brumback, Ty; Giedd, Jay N; Tapert, Susan F

    2015-12-01

    Studies suggest marijuana impacts gray and white matter neural tissue development, however few prospective studies have determined the relationship between cortical thickness and cannabis use spanning adolescence to young adulthood. This study aimed to understand how heavy marijuana use influences cortical thickness trajectories across adolescence. Subjects were adolescents with heavy marijuana use and concomitant alcohol use (MJ+ALC, n=30) and controls (CON, n=38) with limited substance use histories. Participants underwent magnetic resonance imaging and comprehensive substance use assessment at three independent time points. Repeated measures analysis of covariance was used to look at main effects of group, time, and Group × Time interactions on cortical thickness. MJ+ALC showed thicker cortical estimates across the brain (23 regions), particularly in frontal and parietal lobes (ps<.05). More cumulative marijuana use was associated with increased thickness estimates by 3-year follow-up (ps<.05). Heavy marijuana use during adolescence and into young adulthood may be associated with altered neural tissue development and interference with neuromaturation that can have neurobehavioral consequences. Continued follow-up of adolescent marijuana users will help understand ongoing neural changes that are associated with development of problematic use into adulthood, as well as potential for neural recovery with cessation of use.

  19. Internalizing and externalizing psychopathology as predictors of cannabis use disorder onset during adolescence and early adulthood.

    PubMed

    Farmer, Richard F; Seeley, John R; Kosty, Derek B; Gau, Jeff M; Duncan, Susan C; Lynskey, Michael T; Lewinsohn, Peter M

    2015-09-01

    Risk-related liabilities associated with the development of cannabis use disorders (CUDs) during adolescence and early adulthood are thought to be established well before the emergence of the index episode. In this study, internalizing and externalizing psychopathology from earlier developmental periods were evaluated as risk factors for CUDs during adolescence and early adulthood. Participants (N = 816) completed 4 diagnostic assessments between the ages 16 and 30, during which current and past CUDs were assessed as well as a full range of psychiatric disorders associated with internalizing and externalizing psychopathology domains. In unadjusted and adjusted time-to-event analyses, externalizing but not internalizing psychopathology from proximal developmental periods predicted subsequent CUD onset. A large proportion of adolescent and early adult cases, however, did not manifest any externalizing or internalizing psychopathology during developmental periods before CUD onset. Findings are consistent with the emerging view that externalizing disorders from proximal developmental periods are robust risk factors for CUDs. Although the identification of externalizing liabilities may aid in the identification of individuals at risk for embarking on developmental pathways that culminate in CUDs, such liabilities are an incomplete indication of overall risk. PMID:25799438

  20. Applying a Social Determinants of Health Perspective to Early Adolescent Cannabis Use--An Overview

    ERIC Educational Resources Information Center

    Hyshka, Elaine

    2013-01-01

    Cannabis is the most widely used illicit drug in the world. Although the risk of problematic cannabis use is relatively low, the lifetime prevalence of dependence is greater than for all other illicit drugs. As such, the population burden of problematic cannabis use warrants attention. Many health and psychosocial risks associated with cannabis…

  1. Dopamine response to psychosocial stress in chronic cannabis users: a PET study with [11C]-+-PHNO.

    PubMed

    Mizrahi, Romina; Suridjan, Ivonne; Kenk, Miran; George, Tony P; Wilson, Alan; Houle, Sylvain; Rusjan, Pablo

    2013-03-01

    A number of addictions have been linked with decreased striatal dopamine (DA) receptor availability and DA release. Stress has a key role in cannabis craving, as well as in modulation of dopaminergic signaling. The present study aimed to assess DA release in response to a laboratory stress task with [(11)C]-(+)-PHNO positron emission tomography in cannabis users (CU). Thirteen healthy CU and 12 healthy volunteers (HV) were scanned during a sensorimotor control task (SMCT) and under a stress condition using the validated Montreal imaging stress task (MIST). The simplified reference tissue model (SRTM) was used to obtain binding potential (BP(ND)) in striatal subdivisions: limbic striatum (LST), associative striatum (AST), and sensorimotor striatum (SMST). Stress-induced DA release (indexed as a percentage of reduction in [(11)C]-(+)-PHNO BP (ND)) between CU and HV was tested with analysis of variance. SMCT BP(ND) was significantly higher in CU compared with HV in the AST (F=10.38, p=0.003), LST (F=4.95, p=0.036), SMST (F=4.33, p=0.048), and whole striatum (F=9.02, p=0.006). Percentage of displacement (change in BP(ND) between SMCT and MIST PET scans) was not significantly different across groups in any brain region, except in the GP (-5.03±14.6 in CU, compared with 6.15±12.1 in HV; F=4.39, p=0.049). Duration of cannabis use was significantly associated with stress-induced [(11)C]-(+)-PHNO displacement by endogenous DA in the LST (r=0.566, p=0.044), with no effect in any other brain region. In conclusion, despite an increase in striatal BP(ND) observed during the control task, chronic cannabis use is not associated with alterations in stress-induced DA release. PMID:23212454

  2. Plasma Cannabinoid Pharmacokinetics After Controlled Smoking and Ad libitum Cannabis Smoking in Chronic Frequent Users.

    PubMed

    Lee, Dayong; Bergamaschi, Mateus M; Milman, Garry; Barnes, Allan J; Queiroz, Regina H C; Vandrey, Ryan; Huestis, Marilyn A

    2015-10-01

    More Americans are dependent on cannabis than any other illicit drug. The main analytes for cannabis testing include the primary psychoactive constituent, Δ(9)-tetrahydrocannabinol (THC), equipotent 11-hydroxy-THC (11-OH-THC) and inactive 11-nor-9-carboxy-THC (THCCOOH). Eleven adult chronic frequent cannabis smokers resided on a closed research unit with unlimited access to 5.9% THC cannabis cigarettes from 12:00 to 23:00 during two ad libitum smoking phases, followed by a 5-day abstinence period in seven participants. A single cigarette was smoked under controlled topography on the last day of the smoking and abstinence phases. Plasma cannabinoids were quantified by two-dimensional gas chromatography-mass spectrometry. Median plasma maximum concentrations (Cmax) were 28.3 (THC), 3.9 (11-OH-THC) and 47.0 μg/L (THCCOOH) 0.5 h after controlled single cannabis smoking. Median Cmax 0.2-0.5 h after ad libitum smoking was higher for all analytes: 83.5 (THC), 14.2 (11-OH-THC) and 155 μg/L (THCCOOH). All 11 participants' plasma samples were THC and THCCOOH-positive, 58.3% had THC ≥5 μg/L and 79.2% were 11-OH-THC-positive 8.1-14 h after last cannabis smoking. Cannabinoid detection rates in seven participants 106-112 h (4-5 days) after last smoking were 92.9 (THC), 35.7 (11-OH-THC) and 100% (THCCOOH), with limits of quantification of 0.5 μg/L for THC and THCCOOH, and 1.0 μg/L for 11-OH-THC. These data greatly expand prior research findings on cannabinoid excretion profiles in chronic frequent cannabis smokers during ad libitum smoking. Smoking multiple cannabis cigarettes led to higher Cmax and AUC compared with smoking a single cigarette. The chronic frequent cannabis smokers exhibited extended detection windows for plasma cannabinoids, reflecting a large cannabinoid body burden. PMID:26378131

  3. Plasma Cannabinoid Pharmacokinetics After Controlled Smoking and Ad libitum Cannabis Smoking in Chronic Frequent Users

    PubMed Central

    Lee, Dayong; Bergamaschi, Mateus M.; Milman, Garry; Barnes, Allan J.; Queiroz, Regina H.C.; Vandrey, Ryan; Huestis, Marilyn A.

    2015-01-01

    More Americans are dependent on cannabis than any other illicit drug. The main analytes for cannabis testing include the primary psychoactive constituent, Δ9-tetrahydrocannabinol (THC), equipotent 11-hydroxy-THC (11-OH-THC) and inactive 11-nor-9-carboxy-THC (THCCOOH). Eleven adult chronic frequent cannabis smokers resided on a closed research unit with unlimited access to 5.9% THC cannabis cigarettes from 12:00 to 23:00 during two ad libitum smoking phases, followed by a 5-day abstinence period in seven participants. A single cigarette was smoked under controlled topography on the last day of the smoking and abstinence phases. Plasma cannabinoids were quantified by two-dimensional gas chromatography–mass spectrometry. Median plasma maximum concentrations (Cmax) were 28.3 (THC), 3.9 (11-OH-THC) and 47.0 μg/L (THCCOOH) 0.5 h after controlled single cannabis smoking. Median Cmax 0.2–0.5 h after ad libitum smoking was higher for all analytes: 83.5 (THC), 14.2 (11-OH-THC) and 155 μg/L (THCCOOH). All 11 participants' plasma samples were THC and THCCOOH-positive, 58.3% had THC ≥5 μg/L and 79.2% were 11-OH-THC-positive 8.1–14 h after last cannabis smoking. Cannabinoid detection rates in seven participants 106–112 h (4–5 days) after last smoking were 92.9 (THC), 35.7 (11-OH-THC) and 100% (THCCOOH), with limits of quantification of 0.5 μg/L for THC and THCCOOH, and 1.0 μg/L for 11-OH-THC. These data greatly expand prior research findings on cannabinoid excretion profiles in chronic frequent cannabis smokers during ad libitum smoking. Smoking multiple cannabis cigarettes led to higher Cmax and AUC compared with smoking a single cigarette. The chronic frequent cannabis smokers exhibited extended detection windows for plasma cannabinoids, reflecting a large cannabinoid body burden. PMID:26378131

  4. Plasma Cannabinoid Pharmacokinetics After Controlled Smoking and Ad libitum Cannabis Smoking in Chronic Frequent Users.

    PubMed

    Lee, Dayong; Bergamaschi, Mateus M; Milman, Garry; Barnes, Allan J; Queiroz, Regina H C; Vandrey, Ryan; Huestis, Marilyn A

    2015-10-01

    More Americans are dependent on cannabis than any other illicit drug. The main analytes for cannabis testing include the primary psychoactive constituent, Δ(9)-tetrahydrocannabinol (THC), equipotent 11-hydroxy-THC (11-OH-THC) and inactive 11-nor-9-carboxy-THC (THCCOOH). Eleven adult chronic frequent cannabis smokers resided on a closed research unit with unlimited access to 5.9% THC cannabis cigarettes from 12:00 to 23:00 during two ad libitum smoking phases, followed by a 5-day abstinence period in seven participants. A single cigarette was smoked under controlled topography on the last day of the smoking and abstinence phases. Plasma cannabinoids were quantified by two-dimensional gas chromatography-mass spectrometry. Median plasma maximum concentrations (Cmax) were 28.3 (THC), 3.9 (11-OH-THC) and 47.0 μg/L (THCCOOH) 0.5 h after controlled single cannabis smoking. Median Cmax 0.2-0.5 h after ad libitum smoking was higher for all analytes: 83.5 (THC), 14.2 (11-OH-THC) and 155 μg/L (THCCOOH). All 11 participants' plasma samples were THC and THCCOOH-positive, 58.3% had THC ≥5 μg/L and 79.2% were 11-OH-THC-positive 8.1-14 h after last cannabis smoking. Cannabinoid detection rates in seven participants 106-112 h (4-5 days) after last smoking were 92.9 (THC), 35.7 (11-OH-THC) and 100% (THCCOOH), with limits of quantification of 0.5 μg/L for THC and THCCOOH, and 1.0 μg/L for 11-OH-THC. These data greatly expand prior research findings on cannabinoid excretion profiles in chronic frequent cannabis smokers during ad libitum smoking. Smoking multiple cannabis cigarettes led to higher Cmax and AUC compared with smoking a single cigarette. The chronic frequent cannabis smokers exhibited extended detection windows for plasma cannabinoids, reflecting a large cannabinoid body burden.

  5. Cross-national comparison of adolescent drinking and cannabis use in the United States, Canada, and the Netherlands

    PubMed Central

    Simons-Morton, Bruce; Pickett, William; Boyce, Will; ter Bogt, Tom F.M.; Vollebergh, Wilma

    2009-01-01

    Background This research examined the prevalence of drinking and cannabis use among adolescents in the United States, Canada, and the Netherlands, countries with substantially different laws and policies relating to these substances. Method Laws regarding drinking and marijuana use were rated for each country. Substance use prevalence data among 10th graders from the Health Behavior in School-Aged Children Survey conducted in each country in 2005–06 were examined. Results Laws regarding alcohol and cannabis were found to be strictest in the United States, somewhat less strict in Canada, and least strict in the Netherlands. On most measures of drinking, rates were lower in the United States than in Canada or the Netherlands. With United States as the referent, relative risks (RR) for monthly drinking were 1.30 (1.11–1.53) for Canadian boys and 1.55 (1.31–1.83) for girls, and 2.0 (1.73–2.31) for Dutch boys and 1.92 (1.62–2.27) for Dutch girls. Drunkenness was also higher among Canadian boys and girls and Dutch boys. However, rates of cannabis use did not differ between the countries, except that Dutch girls were less likely to use cannabis in the past year (RR= .67; 0.46–0.96). Conclusions The lower prevalence of adolescent drinking and drunkenness (except among Dutch girls) in the United States is consistent with the contention that strict drinking policies may limit drinking among 10th graders. However, the finding that marijuana use rates did not differ across countries is not consistent with the contention that prohibition-oriented policies deter use or that liberal marijuana policies are associated with elevated adolescent use. Based on these findings, the case for strict laws and policies is considerably weaker for marijuana than for alcohol. PMID:19303761

  6. White matter fractional anisotropy over two time points in early onset schizophrenia and adolescent cannabis use disorder: A naturalistic diffusion tensor imaging study.

    PubMed

    Epstein, Katherine A; Kumra, Sanjiv

    2015-04-30

    Recurrent exposure to cannabis in adolescence increases the risk for later development of psychosis, but there are sparse data regarding the impact of cannabis use on brain structure during adolescence. This pilot study investigated the effect of cannabis use disorder (CUD) upon white matter fractional anisotropy (WM FA) values in non-psychotic treatment-seeking adolescents relative to adolescents with early onset schizophrenia-spectrum disorders (EOSS) and to healthy control (HC) participants. Diffusion tensor imaging (DTI) and tractography methods were used to examine fractional anisotropy (FA) of the cingulum bundle, superior longitudinal fasciculus (SLF), corticospinal tract (CST), inferior longitudinal fasciculus (ILF), inferior fronto-occipital fasciculus (IFOF) and uncinate fasciculus in adolescents with EOSS (n=34), CUD (n=19) and HC (n=29). Participants received DTI and substance use assessments at baseline and at 18-month follow-up. Using multivariate analysis of variance, a significant main effect of diagnostic group was observed. Post-hoc testing revealed that adolescents with CUD showed an altered change in FA values in the left ILF and in the left IFOF (trend level) compared with HC adolescents. Greater consumption of cannabis during the inter-scan interval predicted a greater decrease in left ILF FA in CUD. These preliminary longitudinal data suggest that heavy cannabis use during adolescence, or some factor associated with cannabis use, is associated with an altered change in WM FA values in a fiber bundle that has been implicated in the pathophysiology of EOSS (i.e., the left ILF). Additional studies are needed to clarify the clinical significance of these findings.

  7. Are cannabis users who participate in a randomized clinical trial different from other treatment seekers?

    PubMed

    Frewen, Amie R; Baillie, Andrew J; Montebello, Mark E

    2009-04-01

    Randomized controlled trials (RCTs) provide the most convincing evidence for clinical questions concerning the efficacy of interventions. When participants in RCTs are characteristically different to those in usual clinical practice, it may be difficult to generalize findings. This study compares profiles taken from a centralized intake process for those presenting with cannabis as their main drug, which were then separated into three categories, (a) those who were offered a specialist assessment for cannabis dependence over the phone but did not attend their appointment, (b) those who presented for their initial appointment, and c) those attending and subsequently recruited into an RCT. To explore whether issues such as severity of cannabis use and co-occurring disorders acted as a barrier to attending treatment or to inclusion in an RCT, we examined basic triage information. Results indicated that there were no statistically significant differences on selected characteristics between groups, suggesting that RCT participants were representative of treatment seekers, and that the filtering that occurs between those who make phone contact with professional services and those who present to treatment are not necessarily due to presence of patient characteristics such as coexisting medical, psychological issues, or severity of their cannabis use.

  8. Strain dependence of adolescent Cannabis influence on heroin reward and mesolimbic dopamine transmission in adult Lewis and Fischer 344 rats.

    PubMed

    Cadoni, Cristina; Simola, Nicola; Espa, Elena; Fenu, Sandro; Di Chiara, Gaetano

    2015-01-01

    Adolescent Cannabis exposure has been hypothesized to act as a gateway to opiate abuse. In order to investigate the role of genetic background in cannabinoid-opiate interactions, we studied the effect of Δ(9) -tetrahydrocannabinol (THC) exposure of adolescent Lewis and Fischer 344 rats on the responsiveness of accumbens shell and core dopamine (DA), as monitored by microdialysis, to THC and heroin at adulthood. Heroin reward and reinstatement by heroin priming were studied by conditioned place preference (CPP) and cognitive and emotional functions by object recognition, Y maze and elevated plus maze paradigms. THC stimulated shell DA in Lewis but not in Fischer 344 rats. Adolescent THC exposure potentiated DA stimulant effects of heroin in the shell and core of Lewis and only in the core of Fischer 344 rats. Control Lewis rats developed stronger CPP to heroin and resistance to extinction compared with Fischer 344 strain. In Lewis rats, THC exposure did not affect heroin CPP but potentiated the effect of heroin priming. In Fischer 344 rats, THC exposure increased heroin CPP and made it resistant to extinction. Lewis rats showed seeking reactions during extinction and hedonic reactions in response to heroin priming. Moreover, adolescent THC exposure affected emotional function only in Lewis rats. These observations suggest that long-term effects of Cannabis exposure on heroin addictive liability and emotionality are dependent on individual genetic background.

  9. Explanations and expectations: drug narratives among young cannabis users in treatment

    PubMed Central

    Järvinen, Margaretha; Ravn, Signe

    2015-01-01

    This article analyses how young people enrolled in drug addiction treatment in Copenhagen, Denmark, explain their cannabis careers and how they view their possibilities for quitting drug use again. Inspired by Mead and narrative studies of health and illness, the article identifies four different drug use ‘aetiologies’ drawn upon by the interviewees. These cover childhood experiences, self-medication, the influence of friends and cannabis use as a specific lifestyle. A central argument of the article is that these explanations not only concern the past but also point towards the future by assigning the interviewee a more or less agential position in relation to drugs. Further, the drug narratives are viewed as interactional achievements, related to the social context in which they were produced, namely, the institutional setting of the treatment centres. The article is based on 30 qualitative interviews with young people in drug addiction treatment. PMID:25688710

  10. INCANT: a transnational randomized trial of Multidimensional Family Therapy versus treatment as usual for adolescents with cannabis use disorder

    PubMed Central

    2010-01-01

    Background In 2003, the governments of Belgium, France, Germany, the Netherlands and Switzerland agreed that there was a need in Europe for a treatment programme for adolescents with cannabis use disorders and other behavioural problems. Based on an exhaustive literature review of evidence-based treatments and an international experts meeting, Multidimensional Family Therapy (MDFT) was selected for a pilot study first, which was successful, and then for a joint, transnational randomized controlled trial named INCANT (INternational CAnnabis Need for Treatment). Methods/design INCANT is a randomized controlled trial (RCT) with an open-label, parallel group design. This study compares MDFT with treatment as usual (TAU) at and across sites in Brussels, Berlin, Paris, The Hague and Geneva. Assessments are at baseline and at 3, 6, 9 and 12 months after randomization. A minimum of 450 cases in total is required; sites will recruit 60 cases each in Belgium and Switzerland, and a maximum of 120 each in France, Germany and the Netherlands. Eligible for INCANT are adolescents from 13 through 18 years of age with a cannabis use disorder (dependence or abuse), with at least one parent willing to take part in the treatment. Randomization is concealed to, and therefore beyond control by, the researcher/site requesting it. Randomization is stratified as to gender, age and level of cannabis consumption. Assessments focus on substance use; mental function; behavioural problems; and functioning regarding family, school, peers and leisure time. For outcome analyses, the study will use state of the art latent growth curve modelling techniques, including all randomized participants according to the intention-to-treat principle. INCANT has been approved by the appropriate ethical boards in Belgium, France, Germany, the Netherlands, Switzerland, and the University of Miami Miller School of Medicine. INCANT is funded by the (federal) Ministries of Health of Belgium, Germany, the

  11. Characteristics of Steroid Users in an Adolescent School Population.

    ERIC Educational Resources Information Center

    Adlaf, Edward M.; Smart, Reginald G.

    1992-01-01

    Examined rates of steroid use among Ontario adolescent students. Findings from 3,892 students revealed that 1.1 percent reported using steroids over past year. Steroid users were significantly more likely to use stimulants, caffeine, and relaxants than were nonsteroid users. Demographically, steroid users were significantly more likely to be male…

  12. Parenting practices and adolescent risk behavior: rules on smoking and drinking also predict cannabis use and early sexual debut.

    PubMed

    de Looze, Margaretha; van den Eijnden, Regina; Verdurmen, Jacqueline; Vermeulen-Smit, Evelien; Schulten, Ingrid; Vollebergh, Wilma; ter Bogt, Tom

    2012-12-01

    Previous research has provided considerable support for idea that increased parental support and control are strong determinants of lower prevalence levels of adolescent risk behavior. Much less is known on the association between specific parenting practices, such as concrete rules with respect to smoking and drinking and adolescent risk behavior. The present paper examined whether such concrete parental rules (1) have an effect on the targeted behaviors and (2) predict other, frequently co-occurring, risk behaviors (i.e., cannabis use and early sexual intercourse). These hypotheses were tested in a nationally representative sample of 12- to 16-year-old adolescents in the Netherlands. We found that both types of rules were associated with a lower prevalence of the targeted behaviors (i.e., smoking and drinking). In addition, independent of adolescent smoking and drinking behaviors, parental rules on smoking predicted a lower prevalence of cannabis use and early sexual intercourse, and parental rules on alcohol use also predicted a lower prevalence of early sexual intercourse. This study showed that concrete parental rule setting is more strongly related to lower levels of risk behaviors in adolescents compared to the more general parenting practices (i.e., support and control). Additionally, the effects of such rules do not only apply to the targeted behavior but extend to related behaviors as well. These findings are relevant to the public health domain and suggest that a single intervention program that addresses a limited number of concrete parenting practices, in combination with traditional support and control practices, may be effective in reducing risk behaviors in adolescence.

  13. Cannabis and tolerance: acute drug impairment as a function of cannabis use history.

    PubMed

    Ramaekers, J G; van Wel, J H; Spronk, D B; Toennes, S W; Kuypers, K P C; Theunissen, E L; Verkes, R J

    2016-01-01

    Cannabis use history as predictor of neurocognitive response to cannabis intoxication remains subject to scientific and policy debates. The present study assessed the influence of cannabis on neurocognition in cannabis users whose cannabis use history ranged from infrequent to daily use. Drug users (N = 122) received acute doses of cannabis (300 μg/kg THC), cocaine HCl (300 mg) and placebo. Cocaine served as active control for demonstrating neurocognitive test sensitivity. Executive function, impulse control, attention, psychomotor function and subjective intoxication were significantly worse after cannabis administration relative to placebo. Cocaine improved psychomotor function and attention, impaired impulse control and increased feelings of intoxication. Acute effects of cannabis and cocaine on neurocognitive performance were similar across cannabis users irrespective of their cannabis use history. Absence of tolerance implies that that frequent cannabis use and intoxication can be expected to interfere with neurocognitive performance in many daily environments such as school, work or traffic.

  14. Cannabis and tolerance: acute drug impairment as a function of cannabis use history

    PubMed Central

    Ramaekers, J. G.; van Wel, J. H.; Spronk, D. B.; Toennes, S. W.; Kuypers, K. P. C.; Theunissen, E. L.; Verkes, R. J.

    2016-01-01

    Cannabis use history as predictor of neurocognitive response to cannabis intoxication remains subject to scientific and policy debates. The present study assessed the influence of cannabis on neurocognition in cannabis users whose cannabis use history ranged from infrequent to daily use. Drug users (N = 122) received acute doses of cannabis (300 μg/kg THC), cocaine HCl (300 mg) and placebo. Cocaine served as active control for demonstrating neurocognitive test sensitivity. Executive function, impulse control, attention, psychomotor function and subjective intoxication were significantly worse after cannabis administration relative to placebo. Cocaine improved psychomotor function and attention, impaired impulse control and increased feelings of intoxication. Acute effects of cannabis and cocaine on neurocognitive performance were similar across cannabis users irrespective of their cannabis use history. Absence of tolerance implies that that frequent cannabis use and intoxication can be expected to interfere with neurocognitive performance in many daily environments such as school, work or traffic. PMID:27225696

  15. Cannabis and tolerance: acute drug impairment as a function of cannabis use history.

    PubMed

    Ramaekers, J G; van Wel, J H; Spronk, D B; Toennes, S W; Kuypers, K P C; Theunissen, E L; Verkes, R J

    2016-01-01

    Cannabis use history as predictor of neurocognitive response to cannabis intoxication remains subject to scientific and policy debates. The present study assessed the influence of cannabis on neurocognition in cannabis users whose cannabis use history ranged from infrequent to daily use. Drug users (N = 122) received acute doses of cannabis (300 μg/kg THC), cocaine HCl (300 mg) and placebo. Cocaine served as active control for demonstrating neurocognitive test sensitivity. Executive function, impulse control, attention, psychomotor function and subjective intoxication were significantly worse after cannabis administration relative to placebo. Cocaine improved psychomotor function and attention, impaired impulse control and increased feelings of intoxication. Acute effects of cannabis and cocaine on neurocognitive performance were similar across cannabis users irrespective of their cannabis use history. Absence of tolerance implies that that frequent cannabis use and intoxication can be expected to interfere with neurocognitive performance in many daily environments such as school, work or traffic. PMID:27225696

  16. Grey Matter Changes Associated with Heavy Cannabis Use: A Longitudinal sMRI Study.

    PubMed

    Koenders, Laura; Cousijn, Janna; Vingerhoets, Wilhelmina A M; van den Brink, Wim; Wiers, Reinout W; Meijer, Carin J; Machielsen, Marise W J; Veltman, Dick J; Goudriaan, Anneke E; de Haan, Lieuwe

    2016-01-01

    Cannabis is the most frequently used illicit drug worldwide. Cross-sectional neuroimaging studies suggest that chronic cannabis exposure and the development of cannabis use disorders may affect brain morphology. However, cross-sectional studies cannot make a conclusive distinction between cause and consequence and longitudinal neuroimaging studies are lacking. In this prospective study we investigate whether continued cannabis use and higher levels of cannabis exposure in young adults are associated with grey matter reductions. Heavy cannabis users (N = 20, age baseline M = 20.5, SD = 2.1) and non-cannabis using healthy controls (N = 22, age baseline M = 21.6, SD = 2.45) underwent a comprehensive psychological assessment and a T1- structural MRI scan at baseline and 3 years follow-up. Grey matter volumes (orbitofrontal cortex, anterior cingulate cortex, insula, striatum, thalamus, amygdala, hippocampus and cerebellum) were estimated using the software package SPM (VBM-8 module). Continued cannabis use did not have an effect on GM volume change at follow-up. Cross-sectional analyses at baseline and follow-up revealed consistent negative correlations between cannabis related problems and cannabis use (in grams) and regional GM volume of the left hippocampus, amygdala and superior temporal gyrus. These results suggests that small GM volumes in the medial temporal lobe are a risk factor for heavy cannabis use or that the effect of cannabis on GM reductions is limited to adolescence with no further damage of continued use after early adulthood. Long-term prospective studies starting in early adolescence are needed to reach final conclusions.

  17. Grey Matter Changes Associated with Heavy Cannabis Use: A Longitudinal sMRI Study

    PubMed Central

    Cousijn, Janna; Vingerhoets, Wilhelmina A. M.; van den Brink, Wim; Wiers, Reinout W.; Meijer, Carin J.; Machielsen, Marise W. J.; Veltman, Dick J.; Goudriaan, Anneke E.; de Haan, Lieuwe

    2016-01-01

    Cannabis is the most frequently used illicit drug worldwide. Cross-sectional neuroimaging studies suggest that chronic cannabis exposure and the development of cannabis use disorders may affect brain morphology. However, cross-sectional studies cannot make a conclusive distinction between cause and consequence and longitudinal neuroimaging studies are lacking. In this prospective study we investigate whether continued cannabis use and higher levels of cannabis exposure in young adults are associated with grey matter reductions. Heavy cannabis users (N = 20, age baseline M = 20.5, SD = 2.1) and non-cannabis using healthy controls (N = 22, age baseline M = 21.6, SD = 2.45) underwent a comprehensive psychological assessment and a T1- structural MRI scan at baseline and 3 years follow-up. Grey matter volumes (orbitofrontal cortex, anterior cingulate cortex, insula, striatum, thalamus, amygdala, hippocampus and cerebellum) were estimated using the software package SPM (VBM-8 module). Continued cannabis use did not have an effect on GM volume change at follow-up. Cross-sectional analyses at baseline and follow-up revealed consistent negative correlations between cannabis related problems and cannabis use (in grams) and regional GM volume of the left hippocampus, amygdala and superior temporal gyrus. These results suggests that small GM volumes in the medial temporal lobe are a risk factor for heavy cannabis use or that the effect of cannabis on GM reductions is limited to adolescence with no further damage of continued use after early adulthood. Long-term prospective studies starting in early adolescence are needed to reach final conclusions. PMID:27224247

  18. Grey Matter Changes Associated with Heavy Cannabis Use: A Longitudinal sMRI Study.

    PubMed

    Koenders, Laura; Cousijn, Janna; Vingerhoets, Wilhelmina A M; van den Brink, Wim; Wiers, Reinout W; Meijer, Carin J; Machielsen, Marise W J; Veltman, Dick J; Goudriaan, Anneke E; de Haan, Lieuwe

    2016-01-01

    Cannabis is the most frequently used illicit drug worldwide. Cross-sectional neuroimaging studies suggest that chronic cannabis exposure and the development of cannabis use disorders may affect brain morphology. However, cross-sectional studies cannot make a conclusive distinction between cause and consequence and longitudinal neuroimaging studies are lacking. In this prospective study we investigate whether continued cannabis use and higher levels of cannabis exposure in young adults are associated with grey matter reductions. Heavy cannabis users (N = 20, age baseline M = 20.5, SD = 2.1) and non-cannabis using healthy controls (N = 22, age baseline M = 21.6, SD = 2.45) underwent a comprehensive psychological assessment and a T1- structural MRI scan at baseline and 3 years follow-up. Grey matter volumes (orbitofrontal cortex, anterior cingulate cortex, insula, striatum, thalamus, amygdala, hippocampus and cerebellum) were estimated using the software package SPM (VBM-8 module). Continued cannabis use did not have an effect on GM volume change at follow-up. Cross-sectional analyses at baseline and follow-up revealed consistent negative correlations between cannabis related problems and cannabis use (in grams) and regional GM volume of the left hippocampus, amygdala and superior temporal gyrus. These results suggests that small GM volumes in the medial temporal lobe are a risk factor for heavy cannabis use or that the effect of cannabis on GM reductions is limited to adolescence with no further damage of continued use after early adulthood. Long-term prospective studies starting in early adolescence are needed to reach final conclusions. PMID:27224247

  19. Longitudinal changes in white matter microstructure after heavy cannabis use.

    PubMed

    Becker, Mary P; Collins, Paul F; Lim, Kelvin O; Muetzel, R L; Luciana, M

    2015-12-01

    Diffusion tensor imaging (DTI) studies of cannabis users report alterations in brain white matter microstructure, primarily based on cross-sectional research, and etiology of the alterations remains unclear. We report findings from longitudinal voxelwise analyses of DTI data collected at baseline and at a 2-year follow-up on 23 young adult (18-20 years old at baseline) regular cannabis users and 23 age-, sex-, and IQ-matched non-using controls with limited substance use histories. Onset of cannabis use was prior to age 17. Cannabis users displayed reduced longitudinal growth in fractional anisotropy in the central and parietal regions of the right and left superior longitudinal fasciculus, in white matter adjacent to the left superior frontal gyrus, in the left corticospinal tract, and in the right anterior thalamic radiation lateral to the genu of the corpus callosum, along with less longitudinal reduction of radial diffusion in the right central/posterior superior longitudinal fasciculus, corticospinal tract, and posterior cingulum. Greater amounts of cannabis use were correlated with reduced longitudinal growth in FA as was relatively impaired performance on a measure of verbal learning. These findings suggest that continued heavy cannabis use during adolescence and young adulthood alters ongoing development of white matter microstructure, contributing to functional impairment. PMID:26602958

  20. Longitudinal changes in white matter microstructure after heavy cannabis use.

    PubMed

    Becker, Mary P; Collins, Paul F; Lim, Kelvin O; Muetzel, R L; Luciana, M

    2015-12-01

    Diffusion tensor imaging (DTI) studies of cannabis users report alterations in brain white matter microstructure, primarily based on cross-sectional research, and etiology of the alterations remains unclear. We report findings from longitudinal voxelwise analyses of DTI data collected at baseline and at a 2-year follow-up on 23 young adult (18-20 years old at baseline) regular cannabis users and 23 age-, sex-, and IQ-matched non-using controls with limited substance use histories. Onset of cannabis use was prior to age 17. Cannabis users displayed reduced longitudinal growth in fractional anisotropy in the central and parietal regions of the right and left superior longitudinal fasciculus, in white matter adjacent to the left superior frontal gyrus, in the left corticospinal tract, and in the right anterior thalamic radiation lateral to the genu of the corpus callosum, along with less longitudinal reduction of radial diffusion in the right central/posterior superior longitudinal fasciculus, corticospinal tract, and posterior cingulum. Greater amounts of cannabis use were correlated with reduced longitudinal growth in FA as was relatively impaired performance on a measure of verbal learning. These findings suggest that continued heavy cannabis use during adolescence and young adulthood alters ongoing development of white matter microstructure, contributing to functional impairment.

  1. Cannabis dependence in the San Francisco Family Study: age of onset of use, DSM-IV symptoms, withdrawal, and heritability.

    PubMed

    Ehlers, Cindy L; Gizer, Ian R; Vieten, Cassandra; Gilder, David A; Stouffer, Gina M; Lau, Philip; Wilhelmsen, Kirk C

    2010-02-01

    Cannabis is the most widely used illicit drug in the United States, yet the role of genetics in individual symptoms associated with cannabis use disorders has not been evaluated. The purpose of the present set of analyses was to describe the symptomatology and estimate the heritability of DSM-IV criteria/symptoms of cannabis dependence in a large sample of families. Participants were 2524 adults, participating in the University of California San Francisco (UCSF) Family Study of alcoholism. Seventy percent of the sample had ever used cannabis and 13.9% met DSM-IV criteria for cannabis dependence. Younger age at first cannabis use was found to be significantly associated with a shortened survival to becoming cannabis dependent. Although a greater percentage of men met criteria for cannabis dependence, women were found to demonstrate "telescoping" as indexed by a shorter survival time from initial use to dependence as compared to men. A cannabis withdrawal syndrome was identified in users, the primary symptoms of which were nervousness, appetite change, and sleep disturbance. Cannabis use (h(2)=0.31) and dependence (h(2)=0.20), age at first use, individual DSM-IV criteria for dependence, and cannabis-use associated symptoms of depression, trouble concentrating and paranoia were all found to be heritable. These findings suggest that within this population that cannabis use and dependence, as well as individual cannabis dependence symptoms have a significant heritable component, that cannabis dependence is more likely to occur when use begins during adolescence, and that the cannabis dependence syndrome includes a number of heritable untoward psychiatric side effects including withdrawal.

  2. Multimodal neuroimaging of frontal white matter microstructure in early phase schizophrenia: the impact of early adolescent cannabis use

    PubMed Central

    2013-01-01

    Background A disturbance in connectivity between different brain regions, rather than abnormalities within the separate regions themselves, could be responsible for the clinical symptoms and cognitive dysfunctions observed in schizophrenia. White matter, which comprises axons and their myelin sheaths, provides the physical foundation for functional connectivity in the brain. Myelin sheaths are located around the axons and provide insulation through the lipid membranes of oligodendrocytes. Empirical data suggests oligodendroglial dysfunction in schizophrenia, based on findings of abnormal myelin maintenance and repair in regions of deep white matter. The aim of this in vivo neuroimaging project is to assess the impact of early adolescent onset of regular cannabis use on brain white matter tissue integrity, and to differentiate this impact from the white matter abnormalities associated with schizophrenia. The ultimate goal is to determine the liability of early adolescent use of cannabis on brain white matter, in a vulnerable brain. Methods/Design Young adults with schizophrenia at the early stage of the illness (less than 5 years since diagnosis) will be the focus of this project. Four magnetic resonance imaging measurements will be used to assess different cellular aspects of white matter: a) diffusion tensor imaging, b) localized proton magnetic resonance spectroscopy with a focus on the neurochemical N-acetylaspartate, c) the transverse relaxation time constants of regional tissue water, d) and of N-acetylaspartate. These four neuroimaging indices will be assessed within the same brain region of interest, that is, a large white matter fibre bundle located in the frontal region, the left superior longitudinal fasciculus. Discussion We will expand our knowledge regarding current theoretical models of schizophrenia with a more comprehensive multimodal neuroimaging approach to studying the underlying cellular abnormalities of white matter, while taking into

  3. Prevalence and correlates of heavy smoking and nicotine dependence in adolescents with bipolar and cannabis use disorders.

    PubMed

    Heffner, Jaimee L; Anthenelli, Robert M; Adler, Caleb M; Strakowski, Stephen M; Beavers, Jennifer; DelBello, Melissa P

    2013-12-30

    The study examined the prevalence and correlates of heavy smoking and nicotine dependence in adolescents with bipolar and cannabis use disorders. Participants were 80 adolescents between 13 and 22 years of age with co-occurring bipolar I disorder and cannabis abuse or dependence who reported ever trying a cigarette. Diagnostic and symptom severity measures were completed as part of the baseline assessments for a clinical trial. Almost half (49%) of these participants who ever tried a cigarette were current heavy smokers (≥10 cigarettes/day), and 70% met DSM-IV-TR lifetime criteria for nicotine dependence. Heavy smoking was associated with older age, heavier marijuana use and greater compulsive craving, lifetime diagnoses of attention-deficit/hyperactivity disorder, conduct disorder, illicit drug use disorders, and poorer overall functioning. Nicotine dependence was related to White race, higher current mania severity, and poorer overall functioning. These findings suggest that heavy smoking and nicotine dependence were highly prevalent among these adolescents. Although both were associated with greater physical and psychosocial problems, only heavy smoking was linked to a clear pattern of more severe substance-related and psychiatric problems. Further research to elucidate mechanisms and develop interventions to address early, entrenched patterns of co-use of tobacco and marijuana is warranted.

  4. Do Societal Wealth, Family Affluence, and Gender account for Trends in Adolescent Cannabis Use? A 30 Country Cross-National Study

    PubMed Central

    ter Bogt, Tom F.M.; de Looze, Margreet; Molcho, Michal; Godeau, Emmanuelle; Hublet, Anne; Kokkevi, Anna; Kuntsche, Emmanuel; Gabhainn, Saoirse Nic; Franelic, Iva Pejnovic; Simons-Morton, Bruce; Sznitman, Sharon; Vieno, Alessio; Vollebergh, Wilma; Pickett, William

    2013-01-01

    Aims To examine cross-national changes in frequent adolescent cannabis use (40+ times consumed over lifetime at age 15) over time and relate these trends to societal wealth, family affluence, and gender. Design Data from three cycles (2002, 2006, 2010) of the Health Behaviour in School-aged Children (HBSC) Study were used for cross-sectional and trend analyses of adolescent cannabis use. Setting Representative surveys in thirty European and North American countries. Participants 160,606 15-year-old students. Measurements Respondents’ life-time cannabis use, demographics, family affluence (FAS), and frequency of peer contacts were measured individually. Indicators of wealth (Gross Domestic Product per capita, GDP) and perceived availability of cannabis were obtained from national public data bases. Findings The frequency of lifetime cannabis use decreased over time among adolescents in Europe and North America, particularly in Western European countries and the United States of America (Relative Risk (RR) = 0.86: Confidence Interval (CI) 0.79 – 0.93). This trend was not observed consistently in rapidly developing countries in Eastern, Central, and Southern Europe. Over time (2002–2010) cannabis use became: (1) less characteristic of high GDP countries in contrast to lower GDP countries (RR = 0.74: CI 0.57–0.95); (2) less characteristic of youth from high FAS families in contrast to youth from low FAS families (RR = 0.83: CI 0.72–0.96); and (3) characterized by an increasing gender gap, i.e. consumption was higher among males (RR 1.26: CI 1.04–1.53). Perceived availability of cannabis and peer contacts remained strong predictors of frequent cannabis use. Conclusions Among 30 European and North American countries, cannabis use appears to have “trickled down” over time, with developing countries taking on the former (heavier) use pattern of richer countries, and less affluent youth taking on the former (heavier) use pattern of more affluent youth

  5. Ethnicity as manifest in drug-specific vocabulary and subsequent risk of starting cannabis use in early adolescence.

    PubMed

    Wilcox, Holly C; Storr, Carla L; Benoit, Mike Z; Anthony, James C

    2005-01-01

    Working knowledge or vocabulary of drug slang, as a manifestation of learned behavior, might help predict or explain risk of starting to use cannabis in early adolescence. To study this issue, an epidemiologic sample of 1,255 11- to 12-year-olds was assessed for knowledge of cannabis slang terms in 1992, with follow-up in 1993 and 1994. The basic design is that of a prospective and longitudinal study, with recruitment of an epidemiologic sample of children as they entered primary school in a single metropolitan area, also with baseline assessments and randomization to intervention conditions, and subsequent multiple waves of follow-up assessment. Youths assessed in 1992 and who were familiar with terms such as blunts, Mary Jane, roach, and herb were more likely to start using cannabis within the subsequent two years of the follow-up interval, as compared to other youths (estimated relative risk, RR=11.0; 95% CI 3.6-33.7; P<.001). A youth's working vocabulary may signal important variations in health- and disease-related behavior, such as illegal drug use.

  6. Early endothelial dysfunction as a marker of vasculogenic erectile dysfunction in young habitual cannabis users.

    PubMed

    Aversa, A; Rossi, F; Francomano, D; Bruzziches, R; Bertone, C; Santiemma, V; Spera, G

    2008-01-01

    Aim of the study was to evaluate whether endothelial dysfunction is a marker of erectile dysfunction (ED) in recreational drug abuse. Sixty-four non-consecutive men complaining of ED from at least 3 months were included. All patients underwent detailed history about recreational drug abuse and were then submitted to dynamic penile duplex ultrasound (PDU). According to pharmaco-stimulated peak systolic velocity (PSV) cutoff at 35 cm s(-1), patients were divided into two groups: organic (O; n=30) and non-organic (NO; n=34) ED. All subjects and 7 healthy age-matched subjects as controls, underwent veno-occlusive plethysmography (VOP) for the evaluation of endothelium-dependent dilatation of brachial arteries. Blood pressure, total and free testosterone, prolactin, estradiol, low-density lipoprotein and high-density lipoprotein cholesterol were also evaluated; patients were classified with regard to insulin resistance through the HOMA-IR index. Cannabis smoking was more frequent in O-ED vs NO-ED (78% vs 3%, P<0.001) in the absence of any concomitant risk factor or comorbidity for ED. VOP studies revealed impaired endothelium-dependent vasodilatation in O-ED but not in NO-ED and controls (12+/-6 vs 32+/-4 and 34+/-5 ml min(-1), respectively; P=0.003). Overall patients showed a direct relationship between HOMA-IR and PSV (r(2)=0.47, P<0.0001), which was maintained in men with organic ED (r(2)=0.62, P<0.0001). In cannabis consumers, a direct relationship between HOMA-IR and VOP was also found (r(2)=0.74, P<0.0001). Receiver-operating characteristic (ROC) curve analysis revealed that VOP values below 17.22 ml min(-1) were suggestive for vasculogenic ED. We conclude that early endothelial damage may be induced by chronic cannabis use (and endocannabinoid system activation); insulin resistance may be the hallmark of early endothelial dysfunction and may concur to determine vascular ED in the absence of obesity. Further studies are warranted to establish a direct relationship

  7. Psychological Characteristics of Adolescent Steroid Users.

    ERIC Educational Resources Information Center

    Burnett, Kent F.; Kleiman, Mark E.

    1994-01-01

    Used Millon Adolescent Personality Inventory and Profile of Mood States to assess psychological characteristics in 72 adolescent males: 24 adolescent athletes who reported steroid use, 24 athletes with no steroid use, and 24 nonathletes. Although some personality variables differentiated between athletes and nonathletes, no personality variables…

  8. Progress toward pharmacotherapies for cannabis-use disorder: an evidence-based review

    PubMed Central

    Copeland, Jan; Pokorski, Izabella

    2016-01-01

    Cannabis is the most widely used and variably regulated drug in the world, with increasing trends of use being reported in the US, Australia, Asia, and Africa. Evidence has shown a decrease in the age of commencement of cannabis use in some developed countries and a prolongation of risk of initiation to cannabis use beyond adolescence among more recent users. Cannabis use is associated with numerous health risks and long-term morbidity, as well as risk of developing cannabis-use disorders. Cannabis users infrequently seek professional treatment, and normally do so after a decade of use. Cannabis-use disorders are currently treated using a selection of psychosocial interventions. Severity of withdrawal is a factor that increases the risk of relapse, and is the target of pharmacotherapy studies. Currently, there is no approved pharmacotherapy for cannabis-use disorders. A number of approaches have been examined, and trials are continuing to find a safe and effective medication with little abuse liability. PMID:27217809

  9. Progress toward pharmacotherapies for cannabis-use disorder: an evidence-based review.

    PubMed

    Copeland, Jan; Pokorski, Izabella

    2016-01-01

    Cannabis is the most widely used and variably regulated drug in the world, with increasing trends of use being reported in the US, Australia, Asia, and Africa. Evidence has shown a decrease in the age of commencement of cannabis use in some developed countries and a prolongation of risk of initiation to cannabis use beyond adolescence among more recent users. Cannabis use is associated with numerous health risks and long-term morbidity, as well as risk of developing cannabis-use disorders. Cannabis users infrequently seek professional treatment, and normally do so after a decade of use. Cannabis-use disorders are currently treated using a selection of psychosocial interventions. Severity of withdrawal is a factor that increases the risk of relapse, and is the target of pharmacotherapy studies. Currently, there is no approved pharmacotherapy for cannabis-use disorders. A number of approaches have been examined, and trials are continuing to find a safe and effective medication with little abuse liability. PMID:27217809

  10. The toxicology of cannabis and cannabis prohibition.

    PubMed

    Grotenhermen, Franjo

    2007-08-01

    The acute side effects caused by cannabis use are mainly related to psyche and cognition, and to circulation. Euphoria, anxiety, changes in sensory perception, impairment of memory and psychomotor performance are common effects after a dose is taken that exceeds an individually variable threshold. Cannabis consumption may increase heart rate and change blood pressure, which may have serious consequences in people with heart disease. Effects of chronic use may be induction of psychosis and development of dependency to the drug. Effects on cognitive abilities seem to be reversible after abstinence, except possibly in very heavy users. Cannabis exposure in utero may have negative consequences on brain development with subtle impairment of cognitive abilities in later life. Consequences of cannabis smoking may be similar to those of tobacco smoking and should be avoided. Use by young people has more detrimental effects than use by adults. There appear to be promising therapeutic uses of cannabis for a range of indications. Use of moderate doses in a therapeutic context is usually not associated with severe side effects. Current prohibition on cannabis use may also have harmful side effects for the individual and the society, while having little influence on prevalence of use. Harm is greatest for seriously ill people who may benefit from a treatment with cannabis. This makes it difficult to justify criminal penalties against patients. PMID:17712818

  11. The toxicology of cannabis and cannabis prohibition.

    PubMed

    Grotenhermen, Franjo

    2007-08-01

    The acute side effects caused by cannabis use are mainly related to psyche and cognition, and to circulation. Euphoria, anxiety, changes in sensory perception, impairment of memory and psychomotor performance are common effects after a dose is taken that exceeds an individually variable threshold. Cannabis consumption may increase heart rate and change blood pressure, which may have serious consequences in people with heart disease. Effects of chronic use may be induction of psychosis and development of dependency to the drug. Effects on cognitive abilities seem to be reversible after abstinence, except possibly in very heavy users. Cannabis exposure in utero may have negative consequences on brain development with subtle impairment of cognitive abilities in later life. Consequences of cannabis smoking may be similar to those of tobacco smoking and should be avoided. Use by young people has more detrimental effects than use by adults. There appear to be promising therapeutic uses of cannabis for a range of indications. Use of moderate doses in a therapeutic context is usually not associated with severe side effects. Current prohibition on cannabis use may also have harmful side effects for the individual and the society, while having little influence on prevalence of use. Harm is greatest for seriously ill people who may benefit from a treatment with cannabis. This makes it difficult to justify criminal penalties against patients.

  12. Gender Differences in Internalizing Symptoms and Suicide Risk Among Men and Women Seeking Treatment for Cannabis Use Disorder from Late Adolescence to Middle Adulthood.

    PubMed

    Foster, Katherine T; Li, Ningfei; McClure, Erin A; Sonne, Susan C; Gray, Kevin M

    2016-07-01

    Cannabis continues to rise in popularity as the perception of its harmfulness decreases and evidence of its deleterious developmental effect increases. While internalizing distress and suicide risk have been linked with cannabis use problems [DSM-5 cannabis use disorder (CUD); DSM-IV cannabis abuse and dependence] it remains unclear how this association varies over the course of development in treatment-seeking men and women. The current study utilized the National Drug Abuse Treatment Clinical Trials Network (NIDA CTN) to conduct a cross-sectional comparison of internalizing distress and suicide risk among men (n=437) and women (n=163) spanning ages 18-50 who met DSM-5 criteria for CUD. Interactions between gender and developmental stage (i.e., late adolescence, early adulthood, and middle adulthood) were observed for suicide risk and anxiety but not depression problems. Specifically, women seeking CUD treatment in late adolescence and middle adulthood exhibited significantly higher rates of anxiety and suicide risk compared to men seeking treatment during the same developmental stages. Internalizing distress and suicide risk did not differ between treatment-seeking men and women in the early adult stage. Overall, results suggest that the structure of risk for CUD may differ in men and women across the lifespan and that women presenting for CUD treatment during late adolescence and middle adulthood may uniquely benefit from intervention designed to address these elevations in anxiety and suicide risk.

  13. Gender Differences in Internalizing Symptoms and Suicide Risk Among Men and Women Seeking Treatment for Cannabis Use Disorder from Late Adolescence to Middle Adulthood.

    PubMed

    Foster, Katherine T; Li, Ningfei; McClure, Erin A; Sonne, Susan C; Gray, Kevin M

    2016-07-01

    Cannabis continues to rise in popularity as the perception of its harmfulness decreases and evidence of its deleterious developmental effect increases. While internalizing distress and suicide risk have been linked with cannabis use problems [DSM-5 cannabis use disorder (CUD); DSM-IV cannabis abuse and dependence] it remains unclear how this association varies over the course of development in treatment-seeking men and women. The current study utilized the National Drug Abuse Treatment Clinical Trials Network (NIDA CTN) to conduct a cross-sectional comparison of internalizing distress and suicide risk among men (n=437) and women (n=163) spanning ages 18-50 who met DSM-5 criteria for CUD. Interactions between gender and developmental stage (i.e., late adolescence, early adulthood, and middle adulthood) were observed for suicide risk and anxiety but not depression problems. Specifically, women seeking CUD treatment in late adolescence and middle adulthood exhibited significantly higher rates of anxiety and suicide risk compared to men seeking treatment during the same developmental stages. Internalizing distress and suicide risk did not differ between treatment-seeking men and women in the early adult stage. Overall, results suggest that the structure of risk for CUD may differ in men and women across the lifespan and that women presenting for CUD treatment during late adolescence and middle adulthood may uniquely benefit from intervention designed to address these elevations in anxiety and suicide risk. PMID:27211992

  14. WHY NOT POT?: A Review of the Brain-based Risks of Cannabis.

    PubMed

    MacDonald, Kai; Pappas, Katherine

    2016-01-01

    In this review, we provide a historical perspective on marijuana, and survey contemporary research investigating its potential negative effects on the brain. We discuss the evidence regarding cannabis dependence, driving under the influence of cannabis, underachievement, inducing (or worsening) certain psychiatric conditions, and the potential for progression to use of more dangerous drugs-summarized by the acronym DDUMB, a cognitive tool that may help healthcare providers in their risk/benefit discussions with patients who use cannabis. We also review and discuss the impact of marijuana use on target populations, including adolescents (who are at increased risk of harm); heavy users; and people suffering from-or at high risk of- mental illness. While cannabis presents certain subjective, healthrelated, and pecuniary benefits to users, growers, and other entities, it is also associated with several brainbased risks. Understanding these risks aids clinicians and their patients in making informed and balanced decisions regarding the initiation or continuance of marijuana use.

  15. Failure to Sustain Prepulse Inhibition in Adolescent Marijuana Users

    PubMed Central

    Mathias, Charles W.; Blumenthal, Terry D.; Dawes, Michael A.; Liguori, Anthony; Richard, Dawn M.; Bray, Bethany; Tong, Weiqun; Dougherty, Donald M.

    2011-01-01

    Background Marijuana use is typically initiated during adolescence, which is a critical period for neural development. Studies have reported reductions in prepulse inhibition (PPI) among adults who use marijuana chronically, although no human studies have been conducted during the critical adolescent period. Methods This study tested PPI of acoustic startle among adolescents who were either frequent marijuana Users or naïve to the drug (Controls). Adolescents were tested using two intensities of prepulses (70 and 85 dB) combined with a 105 dB startle stimulus, delivered across two testing blocks. Results There was a significant interaction of group by block for PPI; marijuana Users experienced a greater decline in the PPI across the testing session than Controls. The change in PPI of response magnitude for Users was predicted by change in urine THC/creatinine after atleast 18 hours of abstinence, the number of joints used during the previous week before testing, as well as self-reported DSM-IV symptoms of marijuana tolerance, and time spent using marijuana rather than participating in other activities. Conclusions These outcomes suggest that adolescents who are frequent marijuana users have problems maintaining of prepulse inhibition, possibly due to lower quality of information processing or sustained attention, both of may contribute to maintaining continued marijuana use as well as attrition from marijuana treatment. PMID:21196088

  16. Abnormal cerebellar morphometry in abstinent adolescent marijuana users

    PubMed Central

    Medina, Krista Lisdahl; Nagel, Bonnie J.; Tapert, Susan F.

    2010-01-01

    Background Functional neuroimaging data from adults have, in general, found frontocerebellar dysfunction associated with acute and chronic marijuana (MJ) use (Loeber & Yurgelun-Todd, 1999). One structural neuroimaging study found reduced cerebellar vermis volume in young adult MJ users with a history of heavy polysubstance use (Aasly et al., 1993). The goal of this study was to characterize cerebellar volume in adolescent chronic MJ users following one month of monitored abstinence. Method Participants were MJ users (n=16) and controls (n=16) aged 16-18 years. Extensive exclusionary criteria included history of psychiatric or neurologic disorders. Drug use history, neuropsychological data, and structural brain scans were collected after 28 days of monitored abstinence. Trained research staff defined cerebellar volumes (including three cerebellar vermis lobes and both cerebellar hemispheres) on high-resolution T1-weighted magnetic resonance images. Results Adolescent MJ users demonstrated significantly larger inferior posterior (lobules VIII-X) vermis volume (p<.009) than controls, above and beyond effects of lifetime alcohol and other drug use, gender, and intracranial volume. Larger vermis volumes were associated with poorer executive functioning (p’s<.05). Conclusions Following one month of abstinence, adolescent MJ users had significantly larger posterior cerebellar vermis volumes than non-using controls. These greater volumes are suggested to be pathological based on linkage to poorer executive functioning. Longitudinal studies are needed to examine typical cerebellar development during adolescence and the influence of marijuana use. PMID:20413277

  17. Beyond Effects: Adolescents as Active Media Users.

    ERIC Educational Resources Information Center

    Arnett, Jeffrey Jensen; And Others

    1995-01-01

    The articles in this special issue take a "uses and gratifications" approach that emphasizes that people make choices about the media they choose and that they differ in their interpretations of media content. The articles integrate this approach with developmental perspectives on adolescence. (SLD)

  18. Cannabis use among Swedish men in adolescence and the risk of adverse life course outcomes: results from a 20 year‐follow‐up study

    PubMed Central

    Falkstedt, Daniel; Hemmingsson, Tomas; Allebeck, Peter; Agardh, Emilie

    2015-01-01

    Abstract Aims To examine associations between cannabis use in adolescence (at age 18) and unemployment and social welfare assistance in adulthood (at age 40) among Swedish men. Design Longitudinal cohort study. Setting and Participants A total of 49 321 Swedish men born in 1949–51, who were conscripted to compulsory military service at 18–20 years of age. Measurements All men answered two detailed questionnaires at conscription and were subject to examinations of physical aptitude psychological functioning and medical status. By follow‐up in national databases, information on unemployment and social welfare assistance was obtained. Findings Individuals who used cannabis at high levels in adolescence had increased risk of future unemployment and of receiving social welfare assistance. Adjusted for all confounders (social background, psychological functioning, health behaviours, educational level, psychiatric diagnoses), an increased relative risk (RR) of unemployment remained in the group reporting cannabis use > 50 times [RR = 1.26, 95% confidence interval (CI) = 1.04–1.53] only. For social welfare assistance, RR in the group reporting cannabis use 1–10 times was 1.15 (95% CI = 1.06–1.26), RR for 11–50 times was 1.21 (95% CI = 1.04–1.42) and RR for > 50 times was 1.38 (95% CI = 1.19–1.62). Conclusions Heavy cannabis use among Swedish men in late adolescence appears to be associated with unemployment and being in need of social welfare assistance in adulthood. These associations are not explained fully by other health‐related, social or behavioural problems. PMID:26172111

  19. ALTERED PREFRONTAL AND INSULAR CORTICAL THICKNESS IN ADOLESCENT MARIJUANA USERS

    PubMed Central

    Lopez-Larson, Melissa P.; Bogorodzki, Piotr; Rogowska, Jadwiga; McGlade, Erin; King, Jace B.; Terry, Janine; Yurgelun-Todd, Deborah

    2011-01-01

    Introduction There are limited data regarding the impact of marijuana (MJ) on cortical development during adolescence. Adolescence is a period of substantial brain maturation and cortical thickness abnormalities may be indicative of disruptions of normal cortical development. This investigation applied cortical-surface based techniques to compare cortical thickness measures in MJ using adolescents compared to non-using controls. Methods Eighteen adolescents with heavy MJ use and 18 non-using controls similar in age received MRI scans using a 3T Siemens scanner. Cortical reconstruction and volumetric segmentation was performed with FreeSurfer. Group differences in cortical thickness were assessed using statistical difference maps covarying for age and gender. Results Compared to non-users, MJ users had decreased cortical thickness in right caudal middle frontal, bilateral insula and bilateral superior frontal corticies. Marijuana users had increased cortical thickness in the bilateral lingual, right superior temporal, right inferior parietal and left paracentral regions. In the MJ users, negative correlations were found between frontal and lingual regions for urinary cannabinoid levels and between age of onset of use and the right superior frontal gyrus. Conclusion This is one of the first studies to evaluate cortical thickness in a group of adolescents with heavy MJ use compared to non-users. Our findings are consistent with prior studies that documented abnormalities in prefrontal and insular regions. Our results suggest that age of regular use may be associated with altered prefrontal cortical gray matter development in adolescents. Furthermore, reduced insular cortical thickness may be a biological marker for increased risk of substance dependence. PMID:21310189

  20. Do adolescent Ecstasy users have different attitudes towards drugs when compared to Marijuana users?

    PubMed Central

    Martins, Silvia S.; Storr, Carla L.; Alexandre, Pierre K.; Chilcoat, Howard D.

    2008-01-01

    Background Perceived risk and attitudes about the consequences of drug use, perceptions of others expectations and self-efficacy influence the intent to try drugs and continue drug use once use has started. We examine associations between adolescents’ attitudes and beliefs towards ecstasy use; because most ecstasy users have a history of marijuana use, we estimate the association for three groups of adolescents: non-marijuana/ecstasy users, marijuana users (used marijuana at least once but never used ecstasy) and ecstasy users (used ecstasy at least once). Methods Data from 5,049 adolescents aged 12–18 years old who had complete weighted data information in Round 2 of the Restricted Use Files (RUF) of the National Survey of Parents and Youth (NSPY). Data were analyzed using jackknife weighted multinomial logistic regression models. Results Adolescent marijuana and ecstasy users were more likely to approve of marijuana and ecstasy use as compared to non-drug using youth. Adolescent marijuana and ecstasy users were more likely to have close friends who approved of ecstasy as compared to non-drug using youth. The magnitudes of these two associations were stronger for ecstasy use than for marijuana use in the final adjusted model. Our final adjusted model shows that approval of marijuana and ecstasy use was more strongly associated with marijuana and ecstasy use in adolescence than perceived risk in using both drugs. Conclusion Information about the risks and consequences of ecstasy use need to be presented to adolescents in order to attempt to reduce adolescents’ approval of ecstasy use as well as ecstasy experimentation. PMID:18068314

  1. Profiles of Adolescent Substance Abstainers, Users, and Abusers.

    ERIC Educational Resources Information Center

    Hillman, Stephen B.; Sawilowsky, Shlomo S.

    Psychoactive drugs are widely available in the United States. Many, such as coffee, cigarettes, and alcohol, are used commonly and acceptably by adults. For children and adolescents sorting through the complex messages about both licit and illicit drugs is difficult. Previous research examined differences between substance users and abusers with…

  2. Factors That Affect Adolescent Drug Users' Suicide Attempts.

    PubMed

    Park, Subin; Song, Hokwang

    2016-05-01

    Drug abuse has been widely linked to suicide risk. We examined the factors that affect adolescent drug users' suicide attempts in South Korea. This study analyzed the data of 311 adolescents who had used drugs such as inhalants, psychotropic drugs, and marijuana (195 males and 116 females). Among 311 subjects, 109 (35.0%) had attempted suicide during the last 12 months. After adjusting for other variables, depressive mood (OR=19.79) and poly-drug use (OR=2.79), and low/middle levels of academic achievement compared with a high level (OR=3.72 and 4.38) were independently associated with increased odds of a suicide attempt, while better perceived health (OR=0.32) was independently associated with reduced odds of a suicide attempt. For adolescent drug users, preventive work should be directed toward the active treatment of drug use, depression, and physical health and reinforcing proper coping strategies for academic and other stress. PMID:27247604

  3. Factors That Affect Adolescent Drug Users' Suicide Attempts

    PubMed Central

    Song, Hokwang

    2016-01-01

    Drug abuse has been widely linked to suicide risk. We examined the factors that affect adolescent drug users' suicide attempts in South Korea. This study analyzed the data of 311 adolescents who had used drugs such as inhalants, psychotropic drugs, and marijuana (195 males and 116 females). Among 311 subjects, 109 (35.0%) had attempted suicide during the last 12 months. After adjusting for other variables, depressive mood (OR=19.79) and poly-drug use (OR=2.79), and low/middle levels of academic achievement compared with a high level (OR=3.72 and 4.38) were independently associated with increased odds of a suicide attempt, while better perceived health (OR=0.32) was independently associated with reduced odds of a suicide attempt. For adolescent drug users, preventive work should be directed toward the active treatment of drug use, depression, and physical health and reinforcing proper coping strategies for academic and other stress. PMID:27247604

  4. The adverse health effects of chronic cannabis use.

    PubMed

    Hall, Wayne; Degenhardt, Louisa

    2014-01-01

    This paper summarizes the most probable of the adverse health effects of regular cannabis use sustained over years, as indicated by epidemiological studies that have established an association between cannabis use and adverse outcomes; ruled out reverse causation; and controlled for plausible alternative explanations. We have also focused on adverse outcomes for which there is good evidence of biological plausibility. The focus is on those adverse health effects of greatest potential public health significance--those that are most likely to occur and to affect a substantial proportion of regular cannabis users. These most probable adverse effects of regular use include a dependence syndrome, impaired respiratory function, cardiovascular disease, adverse effects on adolescent psychosocial development and mental health, and residual cognitive impairment.

  5. Attitudes to legalizing cannabis use.

    PubMed

    Williams, Jenny; van Ours, Jan C; Grossman, Michael

    2016-09-01

    In this paper, we investigate the relationship between cannabis use and attitudes to legalizing the use of cannabis. Predictions from theory provide a means of learning about the roles of information, self interest and regret in explaining differences in attitudes to legalization between those who currently use, those who have used in the past and those who have never used. Our empirical investigation suggests that users have a greater awareness of cannabis not being as harmful as abstainers think it is. This may explain why individuals are more inclined to be in favor of legalizing cannabis once they have used it themselves. Copyright © 2016 John Wiley & Sons, Ltd.

  6. Do Australian Adolescent Female Fake Tan (Sunless Tan) Users Practice Better Sun-Protection Behaviours than Non-Users?

    ERIC Educational Resources Information Center

    Williams, Melinda; Jones, Sandra C.; Caputi, Peter; Iverson, Don

    2012-01-01

    Objective: To determine differences in sun-protection behaviours, and incidence of sunburn, between Australian adolescent female fake tan users and non-users. Design: Cross sectional survey. Method: 398 adolescent females aged 12 to 18 years participated in a survey at public venues, schools, and online. The main outcome measures were…

  7. Neurocognitive Correlates of White Matter Quality in Adolescent Substance Users

    PubMed Central

    Bava, Sunita; Jacobus, Joanna; Mahmood, Omar; Yang, Tony T.; Tapert, Susan F.

    2009-01-01

    Background Progressive myelination during adolescence implicates an increased vulnerability to neurotoxic substances and enduring neurocognitive consequences. This study examined the cognitive manifestations of altered white matter microstructure in chronic marijuana and alcohol-using (MJ+ALC) adolescents. Methods Thirty-six MJ+ALC adolescents (ages 16-19) and 36 demographically similar controls were evaluated with diffusion tensor imaging (Bava et al., 2009) and neurocognitive tests. Regions of group difference in fractional anisotropy (FA) and mean diffusivity (MD) were analyzed in relation to cognitive performance. Results In users, lower FA in temporal areas related to poorer performance on attention, working memory, and speeded processing tasks. Among regions where users had higher FA than controls, occipital FA was positively associated with working memory and complex visuomotor sequencing, whereas FA in anterior regions was negatively associated with verbal memory performance. Conclusions Findings suggest differential influences of white matter development on cognition in MJ+ALC using adolescents than in non-using peers. Neuroadaptation may reflect additive and subtractive responses to substance use that are complicated by competing maturational processes. PMID:19932550

  8. Dutch coffee shops and trends in cannabis use.

    PubMed

    Korf, Dirk J

    2002-01-01

    Conflicting predictions have been made to the influence of decriminalization on cannabis use. Prohibitionists forecast that decriminalization will lead to an increase in consumption of cannabis, while their opponents hypothesise that cannabis use will decline after decriminalization. Most probably cannabis use in the Netherlands so far evolved in two waves, with a first peak around 1970, a low during the late 1970s and early 1980s, and a second peak in the mid-1990s. It is striking that this trend in cannabis use among youth in the Netherlands rather parallels four identified stages in the availability of cannabis. The number of cannabis users peaked when the cannabis was distributed through an underground market (late 1960s and early 1970s). Then the number decreased as house dealers were superseeding the underground market (1970s), and went up again after coffee shops took over the sale of cannabis (1980s), and stabilised or slightly decreased by the end of the 1990s when the number of coffee shops was reduced. Although changes in cannabis policy went along with changes in availability of cannabis and prevalence of cannabis use, it is questionable whether changes in cannabis policy were causally related to trends in cannabis use. Cannabis use also developed in waves in other European countries that did not decriminalize cannabis, as well as in the US. Consequently, trends in cannabis use seem to develop rather independently of cannabis policy. PMID:12369472

  9. Quality of life and risk of psychiatric disorders among regular users of alcohol, nicotine, and cannabis: An analysis of the National Epidemiological Survey on Alcohol and Related Conditions (NESARC).

    PubMed

    Cougle, Jesse R; Hakes, Jahn K; Macatee, Richard J; Chavarria, Jesus; Zvolensky, Michael J

    2015-01-01

    Research is limited on the effects of regular substance use on mental health-related outcomes. We used a large nationally representative survey to examine current and future quality of life and risk of psychiatric disorders among past-year regular (weekly) users of alcohol, nicotine, and cannabis. Data on psychiatric disorders and quality of life from two waves (Wave 1 N = 43,093, Wave 2 N = 34,653) of the National Epidemiological Survey on Alcohol and Related Conditions (NESARC) were used to test study aims. In cross-sectional analyses, regular nicotine and cannabis use were associated with higher rates of psychiatric disorder, though regular alcohol use was associated with lower rates of disorders. Prospective analyses found that regular nicotine use predicted onset of anxiety, depressive, and bipolar disorders. Regular alcohol use predicted lower risk of these disorders. Regular cannabis use uniquely predicted the development of bipolar disorder, panic disorder with agoraphobia, and social phobia. Lastly, regular alcohol use predicted improvements in physical and mental health-related quality of life, whereas nicotine predicted deterioration in these outcomes. Regular cannabis use predicted declines in mental, but not physical health. These data add to the literature on the relations between substance use and mental and physical health and suggest increased risk of mental health problems among regular nicotine and cannabis users and better mental and physical health among regular alcohol users. Examination of mechanisms underlying these relationships is needed. PMID:26022838

  10. Cannabis and Psychopathology : Update 2004

    PubMed Central

    Grover, Sandeep; Basu, Debasish

    2004-01-01

    The study of cannabis use and psychopathology remains an interesting area from both academic and pragmatic perspectives. This article provides an update on the progress made in this area over the past decade or so. Psychopathology and psychiatric syndromes associated with cannabis use that have received research attention in recent years include cannabis withdrawal, cannabis and psychotic disorders (especially schizophrenia), depression, anxiety, and cognitive impairment. Status of a specific cannabis withdrawal syndrome and a specific ‘cannabis psychosis’ remains controversial. Current evidence indicates that there is a clinically significant association between cannabis use disorders and psychotic syndromes, depression, anxiety and possibly mild cognitive impairment. However, the nature of this association is often not clear. Several hypothesis related to the cannabis-schizophrenia association are examined. Cannabis use might be casually related to the later development of schizophrenia in an indirect way in a few heavy users, but more commonly, its use may precipitate disorders in persons who are vulnerable to developing psychosis and worsen the course of the disorder. PMID:21206788

  11. Shifting the Paradigm: Adolescent Cannabis Abuse and the Need for Early Intervention.

    PubMed

    Golick, Jennifer

    2016-01-01

    This article describes the increasing risks of use of marijuana and related products by adolescents. As THC content increases and methods such as "dabbing" increase frequency of use, risks of marijuana use as perceived by youth are decreasing. At a time when marijuana access is increasing nationally, a new marijuana landscape is forming in which both adolescents and treatment providers must adjust their perceptions of what was once thought of as a "harmless" drug. This article describes this new landscape, and what it may mean for adolescent drug treatment.

  12. Shifting the Paradigm: Adolescent Cannabis Abuse and the Need for Early Intervention.

    PubMed

    Golick, Jennifer

    2016-01-01

    This article describes the increasing risks of use of marijuana and related products by adolescents. As THC content increases and methods such as "dabbing" increase frequency of use, risks of marijuana use as perceived by youth are decreasing. At a time when marijuana access is increasing nationally, a new marijuana landscape is forming in which both adolescents and treatment providers must adjust their perceptions of what was once thought of as a "harmless" drug. This article describes this new landscape, and what it may mean for adolescent drug treatment. PMID:26800275

  13. Gender effects on amygdala morphometry in adolescent marijuana users

    PubMed Central

    McQueeny, Tim; Padula, Claudia B.; Price, Jenessa; Medina, Krista Lisdahl; Logan, Patrick; Tapert, Susan F.

    2011-01-01

    Adolescent developments in limbic structures and the endogenous cannabinoid system suggest that teenagers may be more vulnerable to the negative consequences of marijuana use. This study examined the relationships between amygdala volume and internalizing symptoms in teenaged chronic marijuana users. Participants were 35 marijuana users and 47 controls ages 16–19 years. Exclusions included psychiatric (e.g., mood and anxiety) or neurologic disorders. Substance use, internalizing (anxiety/depression) symptoms and brain scans were collected after 28 days of monitored abstinence. Reliable raters manually traced amygdala and intracranial volumes on high-resolution magnetic resonance images. Female marijuana users had larger right amygdala volumes and more internalizing symptoms than female controls, after covarying head size, alcohol, nicotine and other substance use (p<0.05), while male users had similar volumes as male controls. For female controls and males, worse mood/anxiety was linked to smaller right amygdala volume (p<0.05), whereas more internalizing problems was associated with bigger right amygdala in female marijuana users. Gender interactions may reflect marijuana-related interruptions to sex-specific neuromaturational processes and staging. Subtle amygdala development abnormalities may underlie particular vulnerabilities to sub-diagnostic depression and anxiety in teenage female marijuana users. PMID:21664935

  14. Identification and Characterization of Adolescent Internet User's Profiles.

    PubMed

    Rial, Antonio; Gómez, Patricia; Picón, Eduardo; Braña, Teresa; Varela, Jesús

    2015-01-01

    The percentages of adolescent Internet use in general terms have been measured for nearly two decades now; however, it might be thought that not every teenager behaves online in the same way. This study aims to identify the different types or profiles of adolescents and to characterize them from an attitudinal, behavioral and socio-demographic viewpoint. A questionnaire was applied to a representative sample of 2,339 Compulsory Secondary School students (M = 13.77 years old) from Galicia (a North-Western region of Spain) for this purpose. A two-stage cluster analysis, based on the response pattern in relation to their attitudes toward Internet, was carried out. Four different segments with specific characteristics were identified: the first steppers, the trainees, the sensible users, and the heavy users. Besides the relevance of descriptive data, these results are of particular interest at an applied level, because they could lead to a better fit of programs to prevent risky behaviors and problematic Internet use in adolescents.

  15. What Can Rats Tell Us about Adolescent Cannabis Exposure? Insights from Preclinical Research.

    PubMed

    Renard, Justine; Rushlow, Walter J; Laviolette, Steven R

    2016-06-01

    Marijuana is the most widely used drug of abuse among adolescents. Adolescence is a vulnerable period for brain development, during which time various neurotransmitter systems such as the glutamatergic, GABAergic, dopaminergic, and endocannabinoid systems undergo extensive reorganization to support the maturation of the central nervous system (CNS). ▵-9-tetrahydrocannabinol (THC), the psychoactive component of marijuana, acts as a partial agonist of CB1 cannabinoid receptors (CB1Rs). CB1Rs are abundant in the CNS and are central components of the neurodevelopmental changes that occur during adolescence. Thus, overactivation of CB1Rs by cannabinoid exposure during adolescence has the ability to dramatically alter brain maturation, leading to persistent and enduring changes in adult cerebral function. Increasing preclinical evidence lends support to clinical evidence suggesting that chronic adolescent marijuana exposure may be associated with a higher risk for neuropsychiatric diseases, including schizophrenia. In this review, we present a broad overview of current neurobiological evidence regarding the long-term consequences of adolescent cannabinoid exposure on adult neuropsychiatric-like disorders. PMID:27254841

  16. [MEDICAL CANNABIS].

    PubMed

    Naftali, Timna

    2016-02-01

    The cannabis plant has been known to humanity for centuries as a remedy for pain, diarrhea and inflammation. Current research is inspecting the use of cannabis for many diseases, including multiple sclerosis, epilepsy, dystonia, and chronic pain. In inflammatory conditions cannabinoids improve pain in rheumatoid arthritis and:pain and diarrhea in Crohn's disease. Despite their therapeutic potential, cannabinoids are not free of side effects including psychosis, anxiety, paranoia, dependence and abuse. Controlled clinical studies investigating the therapeutic potential of cannabis are few and small, whereas pressure for expanding cannabis use is increasing. Currently, as long as cannabis is classified as an illicit drug and until further controlled studies are performed, the use of medical cannabis should be limited to patients who failed conventional better established treatment.

  17. [MEDICAL CANNABIS].

    PubMed

    Naftali, Timna

    2016-02-01

    The cannabis plant has been known to humanity for centuries as a remedy for pain, diarrhea and inflammation. Current research is inspecting the use of cannabis for many diseases, including multiple sclerosis, epilepsy, dystonia, and chronic pain. In inflammatory conditions cannabinoids improve pain in rheumatoid arthritis and:pain and diarrhea in Crohn's disease. Despite their therapeutic potential, cannabinoids are not free of side effects including psychosis, anxiety, paranoia, dependence and abuse. Controlled clinical studies investigating the therapeutic potential of cannabis are few and small, whereas pressure for expanding cannabis use is increasing. Currently, as long as cannabis is classified as an illicit drug and until further controlled studies are performed, the use of medical cannabis should be limited to patients who failed conventional better established treatment. PMID:27215115

  18. Infant with Altered Consciousness after Cannabis Passive Inhalation

    ERIC Educational Resources Information Center

    Zarfin, Yehoshua; Yefet, Enav; Abozaid, Said; Nasser, Wael; Mor, Tamer; Finkelstein, Yoram

    2012-01-01

    We report on an infant who was admitted to hospital with severe neurological symptoms following passive inhalation of cannabis. To date, cannabis abuse has been described almost entirely in adolescents and adults. In early childhood, however, cannabis effects were almost exclusively discussed in the context of maternal prenatal exposure, and the…

  19. [Cannabis-induced cognitive and psychiatric disorders].

    PubMed

    Dervaux, Alain; Krebs, Marie-Odile; Laqueille, Xavier

    2014-03-01

    Several studies have shown that Δ-9-THC the main psychoactive constituent of cannabis, can impair cognitive functions, especially attention, episodic memory, working memory and executive functions. These impairments have been related to the duration, frequency, dose and age at onset of cannabis use. Cognitive deficits may disappear with abstinence, but abnormalities may be long-lasting in subjects who began smoking cannabis before age 15. The lifetime prevalence of cannabis use disorders is about 1% in the general population. The main characteristics of cannabis use disorders are craving, persistent desire or unsuccessful efforts to cut down or control cannabis use, and persistent avoidance of familial, social occupational or recreational activities because of cannabis use. Nine prospective longitudinal studies in the generalpopulation have shown that cannabis use is associated with a two-fold increase in the risk of psychotic disorders, particularly schizophrenia, compared to controls. The risk of psychosis increases in a dose-related fashion. A higher risk of schizophrenia is predicted by earlier onset of cannabis use. The effects of cannabis are exerted primarily through THC interaction with cannabinoid (CB) 1 receptors in the brain. Cannabis exposure may disrupt the last steps of brain maturation, through the endocannabinoid system, thereby increasing the risk of psychosis during adolescence.

  20. State of the art treatments for cannabis dependence.

    PubMed

    Danovitch, Itai; Gorelick, David A

    2012-06-01

    The treatment of cannabis dependence can be viewed as a cup half empty or half full. On the one hand, few people who might benefit from treatment actually receive it. Among those who undergo treatment in randomized trials, long-term abstinence is achieved by fewer than 20%. Moderate use goals have been associated with decreases in consequences, but the differential impact of such goals on the long-term course of cannabis dependence is unknown. Optimal duration of treatment is unclear, and certain populations, particularly patients with co-occurring disorders, have not been studied adequately. Twelve-step programs are low cost, effective for other substance use disorders, and readily available in most regions of the world. However, their role and efficacy in cannabis dependence has not been examined. Finally, effective pharmacologic treatments are under development, but none have yet been firmly established. On the other hand, psychotherapeutic strategies used to treat other substance use disorders can be effective for cannabis dependence. A recent meta-analysis of psychosocial interventions for illicit substance use disorders found that treatments for cannabis dependence had comparatively larger effect sizes than treatments for other substance use disorders. Combination therapies have proven most effective, particularly those that begin with a motivational intervention, utilize incentives to enhance the commitment to change, and teach behavioral and cognitive copings skills to prevent relapse. Among adolescents, family engagement and collaboration with community stakeholders adds substantial value. Although only 9% of cannabis users develop cannabis dependence, the volume of people who smoke cannabis ensures that the total number of people in need of help is larger than the capacity of substance abuse specialty services. Thus, although efforts to refine and improve the efficacy of treatment interventions continue, innovations that increase the availability and

  1. Longitudinal Changes in White Matter Integrity Among Adolescent Substance Users

    PubMed Central

    Bava, Sunita; Jacobus, Joanna; Thayer, Rachel E.; Tapert, Susan F.

    2012-01-01

    Background The influence of repeated substance use during adolescent neurodevelopment remains unclear as there have been few prospective investigations. The aims of this study were to identify longitudinal changes in fiber tract integrity associated with alcohol and marijuana use severity over the course of 1.5 years. Method Adolescents with extensive marijuana and alcohol use histories by mid-adolescence (n = 41) and youth with consistently minimal if any substance use (n = 51) were followed over 18 months. Teens received diffusion tensor imaging and detailed substance use assessments with toxicology screening at baseline and 18-month follow-ups (i.e., 182 scans in all), as well as interim substance use interviews each 6 months. Results At 18-month follow-up, substance users showed poorer white matter integrity in seven tracts: (1) right superior longitudinal fasciculus, (2) left superior longitudinal fasciculus, (3) right posterior thalamic radiations, (4) right prefrontal thalamic fibers, (5) right superior temporal gyrus white matter, (6) right inferior longitudinal fasciculus, and (7) left posterior corona radiata (ps< .01). More alcohol use during the interscan interval predicted higher mean diffusivity (i.e., worsened integrity) in right (p<.05) and left (p=.06) superior longitudinal fasciculi, above and beyond baseline values in these bundles. Marijuana use during the interscan interval did not predict change over time. More externalizing behaviors at Time 1 predicted lower fractional anisotropy and higher radial diffusivity (i.e., poorer integrity) of the right prefrontal thalamic fibers (p<.025). Conclusion Findings add to previous cross sectional studies reporting white matter disadvantages in youth with substance use histories. In particular, alcohol use during adolescent neurodevelopment may be linked to reductions in white matter quality in association fiber tracts with frontal connections. In contrast, youth who engage in a variety of risk taking

  2. Cross-section and panel estimates of peer effects in early adolescent cannabis use: With a little help from my 'friends once removed'.

    PubMed

    Moriarty, John; McVicar, Duncan; Higgins, Kathryn

    2016-08-01

    Peer effects in adolescent cannabis are difficult to estimate, due in part to the lack of appropriate data on behaviour and social ties. This paper exploits survey data that have many desirable properties and have not previously been used for this purpose. The data set, collected from teenagers in three annual waves from 2002 to 2004 contains longitudinal information about friendship networks within schools (N = 5020). We exploit these data on network structure to estimate peer effects on adolescents from their nominated friends within school using two alternative approaches to identification. First, we present a cross-sectional instrumental variable (IV) estimate of peer effects that exploits network structure at the second degree, i.e. using information on friends of friends who are not themselves ego's friends to instrument for the cannabis use of friends. Second, we present an individual fixed effects estimate of peer effects using the full longitudinal structure of the data. Both innovations allow a greater degree of control for correlated effects than is commonly the case in the substance-use peer effects literature, improving our chances of obtaining estimates of peer effects than can be plausibly interpreted as causal. Both estimates suggest positive peer effects of non-trivial magnitude, although the IV estimate is imprecise. Furthermore, when we specify identical models with behaviour and characteristics of randomly selected school peers in place of friends', we find effectively zero effect from these 'placebo' peers, lending credence to our main estimates. We conclude that cross-sectional data can be used to estimate plausible positive peer effects on cannabis use where network structure information is available and appropriately exploited.

  3. Cross-section and panel estimates of peer effects in early adolescent cannabis use: With a little help from my 'friends once removed'.

    PubMed

    Moriarty, John; McVicar, Duncan; Higgins, Kathryn

    2016-08-01

    Peer effects in adolescent cannabis are difficult to estimate, due in part to the lack of appropriate data on behaviour and social ties. This paper exploits survey data that have many desirable properties and have not previously been used for this purpose. The data set, collected from teenagers in three annual waves from 2002 to 2004 contains longitudinal information about friendship networks within schools (N = 5020). We exploit these data on network structure to estimate peer effects on adolescents from their nominated friends within school using two alternative approaches to identification. First, we present a cross-sectional instrumental variable (IV) estimate of peer effects that exploits network structure at the second degree, i.e. using information on friends of friends who are not themselves ego's friends to instrument for the cannabis use of friends. Second, we present an individual fixed effects estimate of peer effects using the full longitudinal structure of the data. Both innovations allow a greater degree of control for correlated effects than is commonly the case in the substance-use peer effects literature, improving our chances of obtaining estimates of peer effects than can be plausibly interpreted as causal. Both estimates suggest positive peer effects of non-trivial magnitude, although the IV estimate is imprecise. Furthermore, when we specify identical models with behaviour and characteristics of randomly selected school peers in place of friends', we find effectively zero effect from these 'placebo' peers, lending credence to our main estimates. We conclude that cross-sectional data can be used to estimate plausible positive peer effects on cannabis use where network structure information is available and appropriately exploited. PMID:27391251

  4. Pathways to psychosis in cannabis abuse.

    PubMed

    Shrivastava, Amresh; Johnston, Megan; Terpstra, Kristen; Bureau, Yves

    2015-04-01

    Cannabis has been implicated as a risk factor for the development of schizophrenia, but the exact biological mechanisms remain unclear. In this review, we attempt to understand the neurobiological pathways that link cannabis use to schizophrenia. This has been an area of great debate; despite similarities between cannabis users and schizophrenia patients, the evidence is not sufficient to establish cause-and-effect. There have been advances in the understanding of the mechanisms of cannabis dependence as well as the role of the cannabinoid system in the development of psychosis and schizophrenia. The neurobiological mechanisms associated with the development of psychosis and effects from cannabis use may be similar but remain elusive. In order to better understand these associations, this paper will show common neurobiological and neuroanatomical changes as well as common cognitive dysfunction in cannabis users and patients of schizophrenia. We conclude that epidemiologic evidence highlights potential causal links; however, neurobiological evidence for causality remains weak. PMID:23491968

  5. Pathways to psychosis in cannabis abuse.

    PubMed

    Shrivastava, Amresh; Johnston, Megan; Terpstra, Kristen; Bureau, Yves

    2015-04-01

    Cannabis has been implicated as a risk factor for the development of schizophrenia, but the exact biological mechanisms remain unclear. In this review, we attempt to understand the neurobiological pathways that link cannabis use to schizophrenia. This has been an area of great debate; despite similarities between cannabis users and schizophrenia patients, the evidence is not sufficient to establish cause-and-effect. There have been advances in the understanding of the mechanisms of cannabis dependence as well as the role of the cannabinoid system in the development of psychosis and schizophrenia. The neurobiological mechanisms associated with the development of psychosis and effects from cannabis use may be similar but remain elusive. In order to better understand these associations, this paper will show common neurobiological and neuroanatomical changes as well as common cognitive dysfunction in cannabis users and patients of schizophrenia. We conclude that epidemiologic evidence highlights potential causal links; however, neurobiological evidence for causality remains weak.

  6. Synthetic cannabis and respiratory depression.

    PubMed

    Jinwala, Felecia N; Gupta, Mayank

    2012-12-01

    In recent years, synthetic cannabis use has been increasing in appeal among adolescents, and its use is now at a 30 year peak among high school seniors. The constituents of synthetic cannabis are difficult to monitor, given the drug's easy accessibility. Currently, 40 U.S. states have banned the distribution and use of some known synthetic cannabinoids, and have included these drugs in the Schedule I category. The depressive respiratory effect in humans caused by synthetic cannabis inhalation has not been thoroughly investigated in the medical literature. We are the first to report, to our knowledge, two cases of self-reported synthetic cannabis use leading to respiratory depression and necessary intubation. PMID:23234589

  7. A review of the world cannabis situation.

    PubMed

    Leggett, T

    2006-01-01

    Cannabis is the world's most widely cultivated and consumed illicit drug, but there remain major gaps in our understanding of global cannabis markets. For example, it appears that premium sinsemilla cannabis, often produced indoors in consumer countries, has become more potent in recent years and that its market share is also growing in some areas. This may be leading to greater localization of cannabis markets. It may also be responsible for the increase in the proportion of cannabis users in treatment populations at the international level. Assessing the extent and impact of this trend, however, is hampered both by a lack of international standards on issues such as terminology and by unanswered research questions. In order to arrive at accurate global estimates of the extent of production, there is a need for more scientific data on cannabis yields. On the demand side, more information is required on the question of cannabis dosage and volumes used by both occasional and regular users. Cannabis is not a uniform drug: the impact of using cannabis of differing potencies and chemical compositions needs to be researched. While issues concerning cannabis have been evaluated many times in the past, it remains a highly adaptable plant and, consequently, a dynamic drug, requiring constant reassessment.

  8. Cannabis Mobile Apps: A Content Analysis

    PubMed Central

    Popova, Lucy; Grana, Rachel; Zhao, Shirley; Chavez, Kathryn

    2015-01-01

    Background Mobile technology is pervasive and widely used to obtain information about drugs such as cannabis, especially in a climate of rapidly changing cannabis policy; yet the content of available cannabis apps is largely unknown. Understanding the resources available to those searching for cannabis apps will clarify how this technology is being used to reflect and influence cannabis use behavior. Objective We investigated the content of 59 cannabis-related mobile apps for Apple and Android devices as of November 26, 2014. Methods The Apple and Google Play app stores were searched using the terms “cannabis” and “marijuana.” Three trained coders classified the top 20 apps for each term and each store, using a coding guide. Apps were examined for the presence of 20 content codes derived by the researchers. Results Total apps available for each search term were 124 for cannabis and 218 for marijuana in the Apple App Store, and 250 each for cannabis and marijuana on Google Play. The top 20 apps in each category in each store were coded for 59 independent apps (30 Apple, 29 Google Play). The three most common content areas were cannabis strain classification (33.9%), facts about cannabis (20.3%), and games (20.3%). In the Apple App Store, most apps were free (77%), all were rated “17+” years, and the average user rating was 3.9/5 stars. The most popular apps provided cannabis strain classifications (50%), dispensary information (27%), or general facts about cannabis (27%). Only one app (3%) provided information or resources related to cannabis abuse, addiction, or treatment. On Google Play, most apps were free (93%), rated “high maturity” (79%), and the average user rating was 4.1/5. The most popular app types offered games (28%), phone utilities (eg, wallpaper, clock; 21%) and cannabis food recipes (21%); no apps addressed abuse, addiction, or treatment. Conclusions Cannabis apps are generally free and highly rated. Apps were most often informational

  9. Cannabis Exposure in an Omani Child

    PubMed Central

    Al-Shidhani, Thuraya A.; Arora, Vinita

    2011-01-01

    We report a confirmed case of cannabis exposure in an Omani female child with developmental delay. Cannabis exposure in children can lead to many consequences; for example, chronic use can result in developmental delay, abnormal behaviour, and hyperactivity while there is a risk of coma with acute exposure. It is important for clinicians to consider substance abuse as a differential diagnosis for similar presentations in paediatric patients, noting that children are at risk of cannabis exposure if their parents/caregivers are cannabis users. PMID:22087402

  10. Inhaled medicinal cannabis and the immunocompromised patient.

    PubMed

    Ruchlemer, Rosa; Amit-Kohn, Michal; Raveh, David; Hanuš, Lumír

    2015-03-01

    Medicinal cannabis is an invaluable adjunct therapy for pain relief, nausea, anorexia, and mood modification in cancer patients and is available as cookies or cakes, as sublingual drops, as a vaporized mist, or for smoking. However, as with every herb, various microorganisms are carried on its leaves and flowers which when inhaled could expose the user, in particular immunocompromised patients, to the risk of opportunistic lung infections, primarily from inhaled molds. The objective of this study was to identify the safest way of using medicinal cannabis in immunosuppressed patients by finding the optimal method of sterilization with minimal loss of activity of cannabis. We describe the results of culturing the cannabis herb, three methods of sterilization, and the measured loss of a main cannabinoid compound activity. Systematic sterilization of medicinal cannabis can eliminate the risk of fatal opportunistic infections associated with cannabis among patients at risk. PMID:25216851

  11. Inhaled medicinal cannabis and the immunocompromised patient.

    PubMed

    Ruchlemer, Rosa; Amit-Kohn, Michal; Raveh, David; Hanuš, Lumír

    2015-03-01

    Medicinal cannabis is an invaluable adjunct therapy for pain relief, nausea, anorexia, and mood modification in cancer patients and is available as cookies or cakes, as sublingual drops, as a vaporized mist, or for smoking. However, as with every herb, various microorganisms are carried on its leaves and flowers which when inhaled could expose the user, in particular immunocompromised patients, to the risk of opportunistic lung infections, primarily from inhaled molds. The objective of this study was to identify the safest way of using medicinal cannabis in immunosuppressed patients by finding the optimal method of sterilization with minimal loss of activity of cannabis. We describe the results of culturing the cannabis herb, three methods of sterilization, and the measured loss of a main cannabinoid compound activity. Systematic sterilization of medicinal cannabis can eliminate the risk of fatal opportunistic infections associated with cannabis among patients at risk.

  12. Highly sensitive quantification of unconjugated 11-nor-9-carboxy-Δ(9)-tetrahydrocannabinol in a cannabis user's hair using micropulverized extraction.

    PubMed

    Kuwayama, Kenji; Miyaguchi, Hajime; Yamamuro, Tadashi; Tsujikawa, Kenji; Kanamori, Tatsuyuki; Iwata, Yuko T; Inoue, Hiroyuki

    2016-05-01

    We previously developed a simple and highly sensitive analytical method for 11-nor-9-carboxy-Δ(9)-tetrahydrocannabinol (THC-COOH) in spiked hair using micropulverized extraction (MPE) and liquid chromatography/tandem mass spectrometry (LC/MS/MS). Using this method, we were able to quantify THC-COOH at 0.2pg/mg, which is the cut-off level recommended by the Society of Hair Testing. However, it was impossible to prove the validity of the method and the presence of THC-COOH conjugated with glucuronide in hair because we did not have authentic hair containing THC-COOH at the cut-off levels at that time. In this study, the previously developed method was verified using recently obtained hair from a cannabis user. The concentrations of THC-COOH quantified using the method were 0.36±0.01pg/mg without hydrolyzation for glucuronide and 0.49±0.05pg/mg with hydrolyzation after MPE, whereas the concentration quantified using the conventional alkaline dissolution and gas chromatography/tandem mass spectrometry with negative ion chemical ionization was 0.50±0.02pg/mg. The results proved that THC-COOH could be extracted completely from authentic hair containing THC-COOH at the recommended cut-off level using MPE. In addition, MPE with and without hydrolyzation, unlike alkaline dissolution of hair, enabled the measurement of the percentage of the conjugate form in total THC-COOH. The percentage of conjugated THC-COOH in hair measured using the MPE was approximately 26%, which was greatly different from previously reported data (>75%). The discrimination between conjugated and unconjugated compounds in hair is important to understand the mechanism of drug uptakes into hair. More data obtained with our simple and highly sensitive method from the hair of cannabis users would help to understand the relationship of concentrations between THC-COOH and its conjugate in hair.

  13. Highly sensitive quantification of unconjugated 11-nor-9-carboxy-Δ(9)-tetrahydrocannabinol in a cannabis user's hair using micropulverized extraction.

    PubMed

    Kuwayama, Kenji; Miyaguchi, Hajime; Yamamuro, Tadashi; Tsujikawa, Kenji; Kanamori, Tatsuyuki; Iwata, Yuko T; Inoue, Hiroyuki

    2016-05-01

    We previously developed a simple and highly sensitive analytical method for 11-nor-9-carboxy-Δ(9)-tetrahydrocannabinol (THC-COOH) in spiked hair using micropulverized extraction (MPE) and liquid chromatography/tandem mass spectrometry (LC/MS/MS). Using this method, we were able to quantify THC-COOH at 0.2pg/mg, which is the cut-off level recommended by the Society of Hair Testing. However, it was impossible to prove the validity of the method and the presence of THC-COOH conjugated with glucuronide in hair because we did not have authentic hair containing THC-COOH at the cut-off levels at that time. In this study, the previously developed method was verified using recently obtained hair from a cannabis user. The concentrations of THC-COOH quantified using the method were 0.36±0.01pg/mg without hydrolyzation for glucuronide and 0.49±0.05pg/mg with hydrolyzation after MPE, whereas the concentration quantified using the conventional alkaline dissolution and gas chromatography/tandem mass spectrometry with negative ion chemical ionization was 0.50±0.02pg/mg. The results proved that THC-COOH could be extracted completely from authentic hair containing THC-COOH at the recommended cut-off level using MPE. In addition, MPE with and without hydrolyzation, unlike alkaline dissolution of hair, enabled the measurement of the percentage of the conjugate form in total THC-COOH. The percentage of conjugated THC-COOH in hair measured using the MPE was approximately 26%, which was greatly different from previously reported data (>75%). The discrimination between conjugated and unconjugated compounds in hair is important to understand the mechanism of drug uptakes into hair. More data obtained with our simple and highly sensitive method from the hair of cannabis users would help to understand the relationship of concentrations between THC-COOH and its conjugate in hair. PMID:27020617

  14. The Moderating Effects of Cannabis Use and Decision Making on the Relationship between Conduct Disorder and Risky Sexual Behavior

    PubMed Central

    Ross, J. Megan; Coxe, Stefany; Schuster, Randi M.; Rojas, Angelica; Gonzalez, Raul

    2015-01-01

    Risky sexual behavior (RSB) is a current public health concern affecting adolescents and young adults. Conduct disorder, cannabis use and decision making (DM) ability are interrelated constructs that are relevant to RSB; however, there is little research on the association of DM and RSB. Participants were 79 cannabis users assessed through self-report measures of RSB and mental health, and a timeline follow-back procedure for substance use. DM ability was assessed via the Iowa Gambling Task. We found that more conduct disorder symptoms accounted for unique variance in measures of overall RSB and an earlier initiation of oral sex, even when taking into account DM and cannabis use. Amount of cannabis use and DM ability moderated the relationships between number of conduct disorder symptoms and number of oral sex partners and age of initiation for vaginal sex. An increase in conduct disorder symptoms was associated with more oral sex partners when DM was poor and fewer partners when DM was better, however this relationship was only present at higher levels of cannabis use. Furthermore, when DM was poor, more conduct disorder symptoms predicted a younger age of initiation of vaginal sex, with the age decreasing as amount of cannabis use increased. Determining how DM influences RSB may assist in the identification of novel treatment approaches to reduce engagement in RSB. PMID:25832553

  15. Social Anxiety and Cannabis Use: An Analysis from Ecological Momentary Assessment

    PubMed Central

    Buckner, Julia D.; Crosby, Ross D.; Wonderlich, Stephen A.; Schmidt, Norman B.

    2011-01-01

    Individuals with elevated social anxiety appear especially vulnerable to cannabis-related problems, yet little is known about the antecedents of cannabis-related behaviors among this high-risk population. The present study used ecological momentary assessment (EMA) to examine the relations among social anxiety, cannabis craving, state anxiety, situational variables, and cannabis use in the natural environment during ad-lib cannabis use episodes. Participants were 49 current cannabis users. During the two-week EMA period, social anxiety significantly interacted with cannabis craving to predict cannabis use both cross-sectionally and prospectively. Specifically, individuals with higher social anxiety and craving were most likely to use cannabis. There was a significant social anxiety X state anxiety X others’ use interaction such that when others were using cannabis, those with elevations in both trait social anxiety and state anxiety were the most likely to use cannabis. PMID:22246109

  16. Cannabis expectancies in substance misusers: French validation of the Marijuana Effect Expectancy Questionnaire.

    PubMed

    Guillem, Eric; Notides, Christine; Vorspan, Florence; Debray, Marcel; Nieto, Isabel; Leroux, Mayliss; Lépine, Jean-Pierre

    2011-01-01

    The aim of this study was to evaluate the psychometric properties of the French version of the Marijuana Effect Expectancy Questionnaire (48 items) and study the cannabis expectancies according to the patterns of substance use and psychiatric disorders (DSM-IV). A sample of 263 subjects (average age 33.1 years [SD = 8.7], 56% men) consisting of cannabis users (n = 64), psychiatric inpatients (n = 175, most of whom were hospitalized for withdrawal), and a control group (n = 24) completed the questionnaire. Internal reliability was good (α= .87) and temporal reliability was satisfactory, with 24 of 48 items having a significant κ ≥ .41. Factor analysis showed four main factors that explained 42.1% of the total variance. The women feared Cognitive Impairment and Negative Effects, and Negative Behavioral Effects more than the men. The onset age of cannabis use, onset age of abuse, abuse and dependence were associated with fewer negative expectancies. Cannabis dependents differed from abusers by more Relaxation and Social Facilitation expectancies. Patients with major depressive episodes, panic disorder, social anxiety disorder, or posttraumatic stress disorder feared negative effects the most. Schizophrenic patients expected more Perceptual Enhancement and Craving. The French version of the Marijuana Effect Expectancy Questionnaire has good psychometric properties and is valid to assess cannabis expectancies in adolescents and adults with substance use disorders.

  17. Characteristics of Marijuana Acquisition among a National Sample of Adolescent Users

    ERIC Educational Resources Information Center

    King, Keith A.; Merianos, Ashley L.; Vidourek, Rebecca A.

    2016-01-01

    Background: Because marijuana is becoming more accessible and perceived norms of use are becoming increasingly more favorable, research is needed to understand characteristics of marijuana acquisition among adolescents. Purpose: The study purpose was to examine whether sources and locations where adolescent users obtain and use marijuana differed…

  18. Actor Vocal Training for the Habilitation of Speech in Adolescent Users of Cochlear Implants

    ERIC Educational Resources Information Center

    Holt, Colleen M.; Dowell, Richard C.

    2011-01-01

    This study examined changes to speech production in adolescents with hearing impairment following a period of actor vocal training. In addition to vocal parameters, the study also investigated changes to psychosocial factors such as confidence, self-esteem, and anxiety. The group were adolescent users of cochlear implants (mean age at commencement…

  19. Impulsivity, Attention, Memory, and Decision-Making among Adolescent Marijuana Users

    PubMed Central

    Dougherty, Donald M.; Mathias, Charles W.; Dawes, Michael A.; Furr, R. Michael; Charles, Nora E.; Liguori, Anthony; Shannon, Erin E.; Acheson, Ashley

    2012-01-01

    Rationale Marijuana is a popular drug of abuse among adolescents, and they may be uniquely vulnerable to resulting cognitive and behavioral impairments. Previous studies have found impairments among adolescent marijuana users. However, the majority of this research has examined measures individually rather than multiple domains in a single cohesive analysis. This study used a logistic regression model that combines performance on a range of tasks to identify which measures were most altered among adolescent marijuana users. Objectives The purpose of this research was to determine unique associations between adolescent marijuana user and performances on multiple cognitive and behavioral domains (attention, memory, decision-making, and impulsivity) in 14- to 17-year-olds while simultaneously controlling for performances across the measures to determine which measures most strongly distinguish marijuana users from non-users. Methods Marijuana-using adolescents (n=45) and controls (n=48) were tested. Logistic regression analyses were conducted to test for: (a) differences between marijuana users and non-users on each measure, (b) associations between marijuana use and each measure after controlling for the other measures, and (c) the degree to which (a) and (b) together elucidated differences among marijuana users and non-users. Results Of all the cognitive and behavioral domains tested, impaired short-term recall memory and consequence sensitivity impulsivity were associated with marijuana use after controlling for performances across all measures. Conclusions This study extends previous findings by identifying cognitive and behavioral impairments most strongly associated with adolescent marijuana users. These specific deficits are potential targets of intervention for this at-risk population. PMID:23138434

  20. Cannabis and the maturing brain: Role in psychosis development.

    PubMed

    Crocker, C E; Tibbo, P G

    2015-06-01

    A common viewpoint has proliferated that cannabis use is mostly harmless. Some argue that by not supporting its use, we are missing a great therapeutic opportunity. The general public view on cannabis may partially be a result of poor knowledge translation. In fact, the "war on drugs" approach has not allowed for basic education on the varied effects of cannabis on the brain, especially at highly critical phases of brain development such as adolescence.

  1. Neurocognitive Correlates of White Matter Quality in Adolescent Substance Users

    ERIC Educational Resources Information Center

    Bava, Sunita; Jacobus, Joanna; Mahmood, Omar; Yang, Tony T.; Tapert, Susan F.

    2010-01-01

    Background: Progressive myelination during adolescence implicates an increased vulnerability to neurotoxic substances and enduring neurocognitive consequences. This study examined the cognitive manifestations of altered white matter microstructure in chronic marijuana and alcohol-using (MJ + ALC) adolescents. Methods: Thirty-six MJ + ALC…

  2. Young Adult Cannabis Users Report Greater Propensity for Risk-Taking Only in Non-Monetary Domains

    PubMed Central

    Gilman, Jodi M.; Calderon, Vanessa; Curran, Max T.; Evins, A. Eden

    2014-01-01

    BACKGROUND Though substance use is often associated with elevated risk-taking in real-world scenarios, many risk-taking tasks in experimental psychology using financial gambles fail to find significant differences between individuals with substance use disorders and healthy controls. We assessed whether participants using marijuana would show a greater propensity for risk-taking in distinct domains including, but not limited to, financial risk-taking. METHODS In the current study, we assessed risk-taking in young adult (age 18–25) regular marijuana users and in non-using control participants using a domain-specific risk-taking self-report scale (DOSPERT) encompassing five domains of risk-taking (social, financial, recreational, health/safety, and ethical). We also measured behavioral risk-taking using a laboratory monetary risk-taking task. RESULTS Marijuana users and controls reported significant differences on the social, health/safety, and ethical risk-taking scales, but no differences in the propensity to take recreational or financial risks. Complementing the self-report finding, there were no differences between marijuana users and controls in their performance on the laboratory risk-taking task. CONCLUSIONS These findings suggest that financial risk-taking may be less sensitive than other domains of risk-taking in assessing differences in risky behavior between those who use marijuana and those who do not. In order to more consistently determine whether increased risk-taking is a factor in substance use, it may be necessary to use both monetary risk-taking tasks and complementary assessments of non-monetary-based risk-taking measures. PMID:25577478

  3. Assessing the public health impacts of legalizing recreational cannabis use in the USA.

    PubMed

    Hall, W; Weier, M

    2015-06-01

    A major challenge in assessing the public health impact of legalizing cannabis use in Colorado and Washington State is the absence of any experience with legal cannabis markets. The Netherlands created a de facto legalized cannabis market for recreational use, but policy analysts disagree about how it has affected rates of cannabis use. Some US states have created de facto legal supply of cannabis for medical use. So far this policy does not appear to have increased cannabis use or cannabis-related harm. Given experience with more liberal alcohol policies, the legalization of recreational cannabis use is likely to increase use among current users. It is also likely that legalization will increase the number of new users among young adults but it remains uncertain how many may be recruited, within what time frame, among which groups within the population, and how many of these new users will become regular users.

  4. Medicinal cannabis.

    PubMed

    Murnion, Bridin

    2015-12-01

    A number of therapeutic uses of cannabis and its derivatives have been postulated from preclinical investigations. Possible clinical indications include spasticity and pain in multiple sclerosis, cancer-associated nausea and vomiting, cancer pain and HIV neuropathy. However, evidence is limited, may reflect subjective rather than objective outcomes, and is not conclusive. Controversies lie in how to produce, supply and administer cannabinoid products. Introduction of cannabinoids therapeutically should be supported by a regulatory and educational framework that minimises the risk of harm to patients and the community. The Regulator of Medicinal Cannabis Bill 2014 is under consideration in Australia to address this. Nabiximols is the only cannabinoid on the Australian Register of Therapeutic Goods at present, although cannabidiol has been recommended for inclusion in Schedule 4. PMID:26843715

  5. Medicinal cannabis

    PubMed Central

    Murnion, Bridin

    2015-01-01

    Summary A number of therapeutic uses of cannabis and its derivatives have been postulated from preclinical investigations. Possible clinical indications include spasticity and pain in multiple sclerosis, cancer-associated nausea and vomiting, cancer pain and HIV neuropathy. However, evidence is limited, may reflect subjective rather than objective outcomes, and is not conclusive. Controversies lie in how to produce, supply and administer cannabinoid products. Introduction of cannabinoids therapeutically should be supported by a regulatory and educational framework that minimises the risk of harm to patients and the community. The Regulator of Medicinal Cannabis Bill 2014 is under consideration in Australia to address this. Nabiximols is the only cannabinoid on the Australian Register of Therapeutic Goods at present, although cannabidiol has been recommended for inclusion in Schedule 4. PMID:26843715

  6. Mechanisms underlying the link between cannabis use and prospective memory.

    PubMed

    Cuttler, Carrie; McLaughlin, Ryan J; Graf, Peter

    2012-01-01

    While the effects of cannabis use on retrospective memory have been extensively examined, only a limited number of studies have focused on the links between cannabis use and prospective memory. We conducted two studies to examine the links between cannabis use and both time-based and event-based prospective memory as well as potential mechanisms underlying these links. For the first study, 805 students completed an online survey designed to assess cannabis consumption, problems with cannabis use indicative of a disorder, and frequency of experiencing prospective memory failures. The results showed small to moderate sized correlations between cannabis consumption, problems with cannabis use, and prospective memory. However, a series of mediation analyses revealed that correlations between problems with cannabis use and prospective memory were driven by self-reported problems with retrospective memory. For the second study, 48 non-users (who had never used cannabis), 48 experimenters (who had used cannabis five or fewer times in their lives), and 48 chronic users (who had used cannabis at least three times a week for one year) were administered three objective prospective memory tests and three self-report measures of prospective memory. The results revealed no objective deficits in prospective memory associated with chronic cannabis use. In contrast, chronic cannabis users reported experiencing more internally-cued prospective memory failures. Subsequent analyses revealed that this effect was driven by self-reported problems with retrospective memory as well as by use of alcohol and other drugs. Although our samples were not fully characterized with respect to variables such as neurological disorders and family history of substance use disorders, leaving open the possibility that these variables may play a role in the detected relationships, the present findings indicate that cannabis use has a modest effect on self-reported problems with prospective memory, with a

  7. Cannabis and neuropsychiatry, 1: benefits and risks.

    PubMed

    Andrade, Chittaranjan

    2016-05-01

    Cannabis is popularly believed to be a relatively benign substance. Cannabis is also considered to have potential medical benefits, and medical marijuana has been legislated in many parts of the world. However, a recent meta-analysis found that cannabinoids were associated with only modest benefits for chemotherapy-related nausea and vomiting, small and inconsistent benefits for pain and spasticity, and inconclusive benefits for other indications such as improvement of appetite and weight, reduction in tic severity, and improvement of mood or sleep. On the flip side, cannabinoids and cannabis have acute and long-term adverse effects. In randomized controlled trials, cannabinoids increase the risk of total adverse events, serious adverse events, and dropout due to adverse events. Cannabis impairs cognition, and driving after cannabis use is associated with an increased risk of traffic accidents, including fatal accidents. Long-term cannabis use may lead to dependence, respiratory conditions, psychosis, and possibly cancer, as well. Cannabis use during pregnancy may compromise certain pregnancy outcomes such as fetal growth, and use during adolescence may compromise neurodevelopment, social adjustment, and vocational success. The composition and bioavailability of cannabis vary across preparations of the substance and routes of administration; this limits the ability to generalize the findings of studies. The findings of older research may no longer apply to current strains of cannabis that are higher in psychotogenic content. It is important for medical professionals and the lay public to understand the limitations of the efficacy data and the seriousness of the risks associated with cannabis use in medical and recreational contexts. PMID:27249079

  8. Cannabis and neuropsychiatry, 1: benefits and risks.

    PubMed

    Andrade, Chittaranjan

    2016-05-01

    Cannabis is popularly believed to be a relatively benign substance. Cannabis is also considered to have potential medical benefits, and medical marijuana has been legislated in many parts of the world. However, a recent meta-analysis found that cannabinoids were associated with only modest benefits for chemotherapy-related nausea and vomiting, small and inconsistent benefits for pain and spasticity, and inconclusive benefits for other indications such as improvement of appetite and weight, reduction in tic severity, and improvement of mood or sleep. On the flip side, cannabinoids and cannabis have acute and long-term adverse effects. In randomized controlled trials, cannabinoids increase the risk of total adverse events, serious adverse events, and dropout due to adverse events. Cannabis impairs cognition, and driving after cannabis use is associated with an increased risk of traffic accidents, including fatal accidents. Long-term cannabis use may lead to dependence, respiratory conditions, psychosis, and possibly cancer, as well. Cannabis use during pregnancy may compromise certain pregnancy outcomes such as fetal growth, and use during adolescence may compromise neurodevelopment, social adjustment, and vocational success. The composition and bioavailability of cannabis vary across preparations of the substance and routes of administration; this limits the ability to generalize the findings of studies. The findings of older research may no longer apply to current strains of cannabis that are higher in psychotogenic content. It is important for medical professionals and the lay public to understand the limitations of the efficacy data and the seriousness of the risks associated with cannabis use in medical and recreational contexts.

  9. Adolescents' Beliefs about Marijuana Use: A Comparison of Regular Users, Past Users and Never/Occasional Users

    ERIC Educational Resources Information Center

    Plancherel, Bernard; Bolognini, Monique; Stephan, Philippe; Laget, Jacques; Chinet, Leonie; Bernard, Mathieu; Halfon, Olivier

    2005-01-01

    A questionnaire investigating adolescents' opinions and experiences regarding marijuana use was administered to 163 adolescents and young adults (96 boys and 67 girls) aged 13 to 20 (mean age = 16.8, s.d. = 1.5). Items referred to marijuana and other substances' dangerousness, representations regarding the positive and negative consequences of…

  10. Contributions of social influences and expectations of use to cannabis use in high-school students.

    PubMed

    Chabrol, Henri; Chauchard, Emeline; Mabila, Joel Dicial; Mantoulan, Régine; Adèle, Aurélie; Rousseau, Amélie

    2006-11-01

    The aim of the study was to evaluate the relative contributions of peers cannabis use or non-use, parental approval of such use, adolescents' own beliefs about use, to the prediction of cannabis use. The participants were 559 high-school students who completed questionnaires assessing the frequency of cannabis use, the number of peers using cannabis, the number of peers opposed to cannabis use, parental attitude toward cannabis use, and participants' expectations towards use. The number of peers using cannabis and participants' positive expectations of cannabis use were risk factors for use whereas the number of peers opposed to cannabis use and the negative expectations of use were protective factors. Parental attitudes towards use were not a significant independent predictor of use.

  11. The Cannabis Youth Treatment (CYT) Study: main findings from two randomized trials.

    PubMed

    Dennis, Michael; Godley, Susan H; Diamond, Guy; Tims, Frank M; Babor, Thomas; Donaldson, Jean; Liddle, Howard; Titus, Janet C; Kaminer, Yifrah; Webb, Charles; Hamilton, Nancy; Funk, Rod

    2004-10-01

    This article presents the main outcome findings from two inter-related randomized trials conducted at four sites to evaluate the effectiveness and cost-effectiveness of five short-term outpatient interventions for adolescents with cannabis use disorders. Trial 1 compared five sessions of Motivational Enhancement Therapy plus Cognitive Behavioral Therapy (MET/CBT) with a 12-session regimen of MET and CBT (MET/CBT12) and another that included family education and therapy components (Family Support Network [FSN]). Trial II compared the five-session MET/CBT with the Adolescent Community Reinforcement Approach (ACRA) and Multidimensional Family Therapy (MDFT). The 600 cannabis users were predominately white males, aged 15-16. All five CYT interventions demonstrated significant pre-post treatment during the 12 months after random assignment to a treatment intervention in the two main outcomes: days of abstinence and the percent of adolescents in recovery (no use or abuse/dependence problems and living in the community). Overall, the clinical outcomes were very similar across sites and conditions; however, after controlling for initial severity, the most cost-effective interventions were MET/CBT5 and MET/CBT12 in Trial 1 and ACRA and MET/CBT5 in Trial 2. It is possible that the similar results occurred because outcomes were driven more by general factors beyond the treatment approaches tested in this study; or because of shared, general helping factors across therapies that help these teens attend to and decrease their connection to cannabis and alcohol.

  12. Validation of the Waterpipe Tolerance Questionnaire among Jordanian School-Going Adolescent Waterpipe Users

    PubMed Central

    Alzyoud, Sukaina; Veeranki, Sreenivas P.; Kheirallah, Khalid A.; Shotar, Ali M.; Pbert, Lori

    2016-01-01

    Introduction: Waterpipe use among adolescents has been increasing progressively. Yet no studies were reported to assess the validity and reliability of nicotine dependence scale. The current study aims to assess the validity and reliability of an Arabic version of the modified Waterpipe Tolerance Questionnaire WTQ among school-going adolescent waterpipe users. Methods: In a cross-sectional study conducted in Jordan, information on waterpipe use among 333 school-going adolescents aged 11-18 years was obtained using the Arabic version of the WTQ. An exploratory factor analysis and correlation matrices were conducted to assess validity and reliability of the WTQ. Results: The WTQ had a 0.73 alpha of internal consistency indicating moderate level of reliability. The scale showed multidimensionality with items loading on two factors, namely waterpipe consumption and morning smoking. Conclusion: This study report nicotine dependence level among school-going adolescents who identify themselves as waterpipe users using the WTQ. PMID:26383198

  13. Brain Responses to Musical Feature Changes in Adolescent Cochlear Implant Users

    PubMed Central

    Petersen, Bjørn; Weed, Ethan; Sandmann, Pascale; Brattico, Elvira; Hansen, Mads; Sørensen, Stine Derdau; Vuust, Peter

    2015-01-01

    Cochlear implants (CIs) are primarily designed to assist deaf individuals in perception of speech, although possibilities for music fruition have also been documented. Previous studies have indicated the existence of neural correlates of residual music skills in postlingually deaf adults and children. However, little is known about the behavioral and neural correlates of music perception in the new generation of prelingually deaf adolescents who grew up with CIs. With electroencephalography (EEG), we recorded the mismatch negativity (MMN) of the auditory event-related potential to changes in musical features in adolescent CI users and in normal-hearing (NH) age mates. EEG recordings and behavioral testing were carried out before (T1) and after (T2) a 2-week music training program for the CI users and in two sessions equally separated in time for NH controls. We found significant MMNs in adolescent CI users for deviations in timbre, intensity, and rhythm, indicating residual neural prerequisites for musical feature processing. By contrast, only one of the two pitch deviants elicited an MMN in CI users. This pitch discrimination deficit was supported by behavioral measures, in which CI users scored significantly below the NH level. Overall, MMN amplitudes were significantly smaller in CI users than in NH controls, suggesting poorer music discrimination ability. Despite compliance from the CI participants, we found no effect of the music training, likely resulting from the brevity of the program. This is the first study showing significant brain responses to musical feature changes in prelingually deaf adolescent CI users and their associations with behavioral measures, implying neural predispositions for at least some aspects of music processing. Future studies should test any beneficial effects of a longer lasting music intervention in adolescent CI users. PMID:25705185

  14. Neural Correlates of Verbal Learning in Adolescent Alcohol and Marijuana Users

    PubMed Central

    Schweinsburg, Alecia Dager; Schweinsburg, Brian C.; Nagel, Bonnie J.; Eyler, Lisa T.; Tapert, Susan F.

    2012-01-01

    Aims Alcohol and marijuana are the most widely used intoxicants among adolescents, yet their potential unique and interactive influences on the developing brain are not well established. Brain regions subserving learning and memory undergo continued maturation during adolescence, and may be particularly susceptible to substance-related neurotoxic damage. Here, we characterize brain response during verbal learning among adolescent users of alcohol and marijuana. Design Participants performed a verbal paired associates encoding task during fMRI scanning. Setting Adolescent subjects were recruited from local public schools and imaged at a University-based fMRI Center. Participants Participants were 74 16- to 18-year-olds, divided into four groups: (1) 22 controls with limited alcohol and marijuana experience, (2) 16 binge drinkers, (3) 8 marijuana users, and (4) 28 binge drinking marijuana users. Measurements Diagnostic interview assured that all teens were free from neurologic or psychiatric disorders; urine toxicology and breathalyzer verified abstinence for 22–28 days before scanning; a verbal paired associates task was administered during fMRI. Findings Groups demonstrated no differences in performance on the verbal encoding task, yet exhibited different brain response patterns. A main effect of drinking pointed to decreased inferior frontal but increased dorsal frontal and parietal fMRI response among binge drinkers (corrected p < .05). There was no main effect of marijuana use. Binge drinking × marijuana interactions were found in bilateral frontal regions (corrected p < .05), where users of either alcohol or marijuana showed greater response than non-users, but users of both substances resembled non-users. Conclusions Adolescent substance users demonstrated altered fMRI response relative to nonusing controls, yet binge drinking appeared associated with more differences in activation than marijuana use. Alcohol and marijuana may have interactive effects that

  15. Brain responses to musical feature changes in adolescent cochlear implant users.

    PubMed

    Petersen, Bjørn; Weed, Ethan; Sandmann, Pascale; Brattico, Elvira; Hansen, Mads; Sørensen, Stine Derdau; Vuust, Peter

    2015-01-01

    Cochlear implants (CIs) are primarily designed to assist deaf individuals in perception of speech, although possibilities for music fruition have also been documented. Previous studies have indicated the existence of neural correlates of residual music skills in postlingually deaf adults and children. However, little is known about the behavioral and neural correlates of music perception in the new generation of prelingually deaf adolescents who grew up with CIs. With electroencephalography (EEG), we recorded the mismatch negativity (MMN) of the auditory event-related potential to changes in musical features in adolescent CI users and in normal-hearing (NH) age mates. EEG recordings and behavioral testing were carried out before (T1) and after (T2) a 2-week music training program for the CI users and in two sessions equally separated in time for NH controls. We found significant MMNs in adolescent CI users for deviations in timbre, intensity, and rhythm, indicating residual neural prerequisites for musical feature processing. By contrast, only one of the two pitch deviants elicited an MMN in CI users. This pitch discrimination deficit was supported by behavioral measures, in which CI users scored significantly below the NH level. Overall, MMN amplitudes were significantly smaller in CI users than in NH controls, suggesting poorer music discrimination ability. Despite compliance from the CI participants, we found no effect of the music training, likely resulting from the brevity of the program. This is the first study showing significant brain responses to musical feature changes in prelingually deaf adolescent CI users and their associations with behavioral measures, implying neural predispositions for at least some aspects of music processing. Future studies should test any beneficial effects of a longer lasting music intervention in adolescent CI users.

  16. Brain responses to musical feature changes in adolescent cochlear implant users.

    PubMed

    Petersen, Bjørn; Weed, Ethan; Sandmann, Pascale; Brattico, Elvira; Hansen, Mads; Sørensen, Stine Derdau; Vuust, Peter

    2015-01-01

    Cochlear implants (CIs) are primarily designed to assist deaf individuals in perception of speech, although possibilities for music fruition have also been documented. Previous studies have indicated the existence of neural correlates of residual music skills in postlingually deaf adults and children. However, little is known about the behavioral and neural correlates of music perception in the new generation of prelingually deaf adolescents who grew up with CIs. With electroencephalography (EEG), we recorded the mismatch negativity (MMN) of the auditory event-related potential to changes in musical features in adolescent CI users and in normal-hearing (NH) age mates. EEG recordings and behavioral testing were carried out before (T1) and after (T2) a 2-week music training program for the CI users and in two sessions equally separated in time for NH controls. We found significant MMNs in adolescent CI users for deviations in timbre, intensity, and rhythm, indicating residual neural prerequisites for musical feature processing. By contrast, only one of the two pitch deviants elicited an MMN in CI users. This pitch discrimination deficit was supported by behavioral measures, in which CI users scored significantly below the NH level. Overall, MMN amplitudes were significantly smaller in CI users than in NH controls, suggesting poorer music discrimination ability. Despite compliance from the CI participants, we found no effect of the music training, likely resulting from the brevity of the program. This is the first study showing significant brain responses to musical feature changes in prelingually deaf adolescent CI users and their associations with behavioral measures, implying neural predispositions for at least some aspects of music processing. Future studies should test any beneficial effects of a longer lasting music intervention in adolescent CI users. PMID:25705185

  17. AKT1 genotype moderates the acute psychotomimetic effects of naturalistically smoked cannabis in young cannabis smokers.

    PubMed

    Morgan, C J A; Freeman, T P; Powell, J; Curran, H V

    2016-01-01

    Smoking cannabis daily doubles an individual's risk of developing a psychotic disorder, yet indicators of specific vulnerability have proved largely elusive. Genetic variation is one potential risk modifier. Single-nucleotide polymorphisms in the AKT1 and catechol-O-methyltransferase (COMT) genes have been implicated in the interaction between cannabis, psychosis and cognition, but no studies have examined their impact on an individual's acute response to smoked cannabis. A total 442 healthy young cannabis users were tested while intoxicated with their own cannabis-which was analysed for delta-9-tetrahydrocannbinol (THC) and cannabidiol content-and also ± 7 days apart when drug-free. Psychotomimetic symptoms and working memory were assessed on both the sessions. Variation at the rs2494732 locus of the AKT1 gene predicted acute psychotic response to cannabis along with dependence on the drug and baseline schizotypal symptoms. Working memory following cannabis acutely was worse in females, with some suggestion of an impact of COMT polymorphism on working memory when drug-free. These findings are the first to demonstrate that AKT1 mediates the acute response to cannabis in otherwise healthy individuals and implicate the AKT1 pathway as a possible target for prevention and treatment of cannabis psychosis. PMID:26882038

  18. Gone to Pot - A Review of the Association between Cannabis and Psychosis.

    PubMed

    Radhakrishnan, Rajiv; Wilkinson, Samuel T; D'Souza, Deepak Cyril

    2014-01-01

    Cannabis is the most commonly used illicit drug worldwide, with ~5 million daily users worldwide. Emerging evidence supports a number of associations between cannabis and psychosis/psychotic disorders, including schizophrenia. These associations-based on case-studies, surveys, epidemiological studies, and experimental studies indicate that cannabinoids can produce acute, transient effects; acute, persistent effects; and delayed, persistent effects that recapitulate the psychopathology and psychophysiology seen in schizophrenia. Acute exposure to both cannabis and synthetic cannabinoids (Spice/K2) can produce a full range of transient psychotomimetic symptoms, cognitive deficits, and psychophysiological abnormalities that bear a striking resemblance to symptoms of schizophrenia. In individuals with an established psychotic disorder, cannabinoids can exacerbate symptoms, trigger relapse, and have negative consequences on the course of the illness. Several factors appear to moderate these associations, including family history, genetic factors, history of childhood abuse, and the age at onset of cannabis use. Exposure to cannabinoids in adolescence confers a higher risk for psychosis outcomes in later life and the risk is dose-related. Individuals with polymorphisms of COMT and AKT1 genes may be at increased risk for psychotic disorders in association with cannabinoids, as are individuals with a family history of psychotic disorders or a history of childhood trauma. The relationship between cannabis and schizophrenia fulfills many but not all of the standard criteria for causality, including temporality, biological gradient, biological plausibility, experimental evidence, consistency, and coherence. At the present time, the evidence indicates that cannabis may be a component cause in the emergence of psychosis, and this warrants serious consideration from the point of view of public health policy. PMID:24904437

  19. Gone to Pot – A Review of the Association between Cannabis and Psychosis

    PubMed Central

    Radhakrishnan, Rajiv; Wilkinson, Samuel T.; D’Souza, Deepak Cyril

    2014-01-01

    Cannabis is the most commonly used illicit drug worldwide, with ~5 million daily users worldwide. Emerging evidence supports a number of associations between cannabis and psychosis/psychotic disorders, including schizophrenia. These associations-based on case-studies, surveys, epidemiological studies, and experimental studies indicate that cannabinoids can produce acute, transient effects; acute, persistent effects; and delayed, persistent effects that recapitulate the psychopathology and psychophysiology seen in schizophrenia. Acute exposure to both cannabis and synthetic cannabinoids (Spice/K2) can produce a full range of transient psychotomimetic symptoms, cognitive deficits, and psychophysiological abnormalities that bear a striking resemblance to symptoms of schizophrenia. In individuals with an established psychotic disorder, cannabinoids can exacerbate symptoms, trigger relapse, and have negative consequences on the course of the illness. Several factors appear to moderate these associations, including family history, genetic factors, history of childhood abuse, and the age at onset of cannabis use. Exposure to cannabinoids in adolescence confers a higher risk for psychosis outcomes in later life and the risk is dose-related. Individuals with polymorphisms of COMT and AKT1 genes may be at increased risk for psychotic disorders in association with cannabinoids, as are individuals with a family history of psychotic disorders or a history of childhood trauma. The relationship between cannabis and schizophrenia fulfills many but not all of the standard criteria for causality, including temporality, biological gradient, biological plausibility, experimental evidence, consistency, and coherence. At the present time, the evidence indicates that cannabis may be a component cause in the emergence of psychosis, and this warrants serious consideration from the point of view of public health policy. PMID:24904437

  20. Limitations to the Dutch cannabis toleration policy: Assumptions underlying the reclassification of cannabis above 15% THC.

    PubMed

    Van Laar, Margriet; Van Der Pol, Peggy; Niesink, Raymond

    2016-08-01

    The Netherlands has seen an increase in Δ9-tetrahydrocannabinol (THC) concentrations from approximately 8% in the 1990s up to 20% in 2004. Increased cannabis potency may lead to higher THC-exposure and cannabis related harm. The Dutch government officially condones the sale of cannabis from so called 'coffee shops', and the Opium Act distinguishes cannabis as a Schedule II drug with 'acceptable risk' from other drugs with 'unacceptable risk' (Schedule I). Even in 1976, however, cannabis potency was taken into account by distinguishing hemp oil as a Schedule I drug. In 2011, an advisory committee recommended tightening up legislation, leading to a 2013 bill proposing the reclassification of high potency cannabis products with a THC content of 15% or more as a Schedule I drug. The purpose of this measure was twofold: to reduce public health risks and to reduce illegal cultivation and export of cannabis by increasing punishment. This paper focuses on the public health aspects and describes the (explicit and implicit) assumptions underlying this '15% THC measure', as well as to what extent these are supported by scientific research. Based on scientific literature and other sources of information, we conclude that the 15% measure can provide in theory a slight health benefit for specific groups of cannabis users (i.e., frequent users preferring strong cannabis, purchasing from coffee shops, using 'steady quantities' and not changing their smoking behaviour), but certainly not for all cannabis users. These gains should be weighed against the investment in enforcement and the risk of unintended (adverse) effects. Given the many assumptions and uncertainty about the nature and extent of the expected buying and smoking behaviour changes, the measure is a political choice and based on thin evidence. PMID:27471078

  1. Limitations to the Dutch cannabis toleration policy: Assumptions underlying the reclassification of cannabis above 15% THC.

    PubMed

    Van Laar, Margriet; Van Der Pol, Peggy; Niesink, Raymond

    2016-08-01

    The Netherlands has seen an increase in Δ9-tetrahydrocannabinol (THC) concentrations from approximately 8% in the 1990s up to 20% in 2004. Increased cannabis potency may lead to higher THC-exposure and cannabis related harm. The Dutch government officially condones the sale of cannabis from so called 'coffee shops', and the Opium Act distinguishes cannabis as a Schedule II drug with 'acceptable risk' from other drugs with 'unacceptable risk' (Schedule I). Even in 1976, however, cannabis potency was taken into account by distinguishing hemp oil as a Schedule I drug. In 2011, an advisory committee recommended tightening up legislation, leading to a 2013 bill proposing the reclassification of high potency cannabis products with a THC content of 15% or more as a Schedule I drug. The purpose of this measure was twofold: to reduce public health risks and to reduce illegal cultivation and export of cannabis by increasing punishment. This paper focuses on the public health aspects and describes the (explicit and implicit) assumptions underlying this '15% THC measure', as well as to what extent these are supported by scientific research. Based on scientific literature and other sources of information, we conclude that the 15% measure can provide in theory a slight health benefit for specific groups of cannabis users (i.e., frequent users preferring strong cannabis, purchasing from coffee shops, using 'steady quantities' and not changing their smoking behaviour), but certainly not for all cannabis users. These gains should be weighed against the investment in enforcement and the risk of unintended (adverse) effects. Given the many assumptions and uncertainty about the nature and extent of the expected buying and smoking behaviour changes, the measure is a political choice and based on thin evidence.

  2. Adolescents' Attitudes toward Wheelchair Users: A Provincial Survey

    ERIC Educational Resources Information Center

    Arbour-Nicitopoulos, Kelly P.

    2010-01-01

    The study aims were to examine (i) adolescents' attitudes towards family members who use a wheelchair in relation to other health problems and conditions, and (ii) the association between perceived wheelchair stigma and socio-demographic factors. Data were based on surveys from 2790 seventh to 12th grade students derived from the 2007 cycle of the…

  3. Psychological adverse effects of cannabis smoking: a tentative classification.

    PubMed

    Nigrete, J C

    1973-01-20

    This paper stresses the need for an early definition and description of the "deviant" cannabis smoker in North America. Attention is called to the fact that on this continent heavy smokers have not yet been separated as "problem" users from other smokers.A comprehensive review of possible psychological adverse effects of the drug is made. The following classification is suggested: a) Severe intoxications, b) Pathological intoxications, c) Acute cannabis psychoses, d) Subacute and chronic cannabis psychoses and e) Residual conditions.

  4. Psychological adverse effects of cannabis smoking: a tentative classification.

    PubMed

    Nigrete, J C

    1973-01-20

    This paper stresses the need for an early definition and description of the "deviant" cannabis smoker in North America. Attention is called to the fact that on this continent heavy smokers have not yet been separated as "problem" users from other smokers.A comprehensive review of possible psychological adverse effects of the drug is made. The following classification is suggested: a) Severe intoxications, b) Pathological intoxications, c) Acute cannabis psychoses, d) Subacute and chronic cannabis psychoses and e) Residual conditions. PMID:4569453

  5. [Cannabis: Use and dependence].

    PubMed

    Dervaux, Alain; Laqueille, Xavier

    2012-12-01

    The main characteristics of cannabis dependence are craving, persistent desire or unsuccessful efforts to cut down or control cannabis use and important social, occupational, or recreational activities given up or reduced because of cannabis use. Withdrawal symptoms include insomnia, irritability, anger, restlessness, depression, mood swings and cravings. Regular cannabis use induces cognitive impairment, especially of attention, episodic memory and working memory. Alcohol and other substances abuse or dependence are frequently found in patients with cannabis dependence. Psychiatric comorbidities are frequent in patients with cannabis dependence, in particular anxiety disorders, mood disorders, and personality disorders. The treatment of cannabis dependence includes behavioral psychotherapy, especially motivational interviewing and cognitive-behavioral therapy, alongside treatment of co-occurring mental health and substance use conditions. There are currently no available pharmacological treatment interventions for cannabis dependence. The treatment of cannabis dependence and withdrawal remains nonspecific. PMID:23040955

  6. Helium inhalation in adolescents: characteristics of users and prevalence of use.

    PubMed

    Whitt, Ahmed; Garland, Eric L; Howard, Matthew O

    2012-01-01

    Although helium-related fatalities and concerns about potentially harmful effects of helium use have increased in recent years, virtually nothing is known about the epidemiology of helium inhalation in adolescents. This exploratory investigation examined the prevalence and correlates of helium inhalation in a large sample of at-risk youth. Study participants were 723 Missouri adolescents (M age = 15.5, SD = 1.2) in residential treatment for delinquent behavior. More than one-in-nine (N = 81, 11.5%) adolescents had inhaled helium with the intention of getting high, and one-third (N = 27, 34.2%) of helium users reported they actually did get high when they inhaled helium. Helium users were significantly more likely to be Caucasian, to live in rural/small town areas, and to have histories of mental illness, auditory hallucinations, and alcohol and marijuana use than nonusers. Helium users also reported significantly more current psychiatric distress, suicidality, traumatic life experiences, and antisocial attitudes, traits, and behaviors than nonusers. Helium inhalation was prevalent in this sample and many such users reported getting high while using helium. Helium users had psychosocial profiles similar to those of volatile solvent users, suggesting that they may be at substantial risk for a variety of adverse health outcomes.

  7. The Association between Internet User Characteristics and Dimensions of Internet Addiction among Greek Adolescents

    ERIC Educational Resources Information Center

    Andreou, Eleni; Svoli, Hionia

    2013-01-01

    This study examined how internet users' psychological characteristics, amount of internet use and demographic factors contribute to particular dimensions of internet addiction. The sample consisted of 384 adolescents, ranging in age from 15 to 18 years. Participants were asked to complete the Internet Addiction Test (IAT), measures of Locus of…

  8. The occurrence of cannabis use disorders and other cannabis-related problems among first-year college students.

    PubMed

    Caldeira, Kimberly M; Arria, Amelia M; O'Grady, Kevin E; Vincent, Kathryn B; Wish, Eric D

    2008-03-01

    This study reports the prevalence of cannabis use disorders (CUD) and other cannabis-related problems in a large cohort (n=1253) of first-year college students, 17 to 20 years old, at one large public university in the mid-Atlantic region of the U.S. Interviewers assessed past-year cannabis use, other drug use, and cannabis-related problems (including DSM-IV criteria for CUD). The prevalence of CUD was 9.4%(wt) among all first-year students and 24.6% among past-year cannabis users (n=739). Of those endorsing any CUD criteria, 33.8% could be classified as diagnostic orphans. Among 474 "at-risk" cannabis users (>or= 5 times in the past year), concentration problems (40.1%), driving while high (18.6%) and missing class (13.9%) were among the most prevalent cannabis-related problems, even among those who endorsed no CUD criteria. Placing oneself at risk for physical injury was also commonly reported (24.3%). A significant proportion of cannabis-using college students meet diagnostic criteria for disorder. Even in the absence of disorder, users appear to be at risk for potentially serious cannabis-related problems. Implications for prevention, service delivery, and future research are discussed.

  9. Does liberalizing cannabis laws increase cannabis use?

    PubMed

    Williams, Jenny; Bretteville-Jensen, Anne Line

    2014-07-01

    A key question in the ongoing policy debate over cannabis' legal status is whether liberalizing cannabis laws leads to an increase in cannabis use. This paper provides new evidence on the impact of a specific type of liberalization, decriminalization, on initiation into cannabis use. Our identification strategy exploits variation in the timing of cannabis policy reforms and our estimation framework marries a difference-in-difference approach with a discrete time duration model. Our results reveal evidence of both heterogeneity and dynamics in the response of cannabis uptake to decriminalization. Overall, we find that the impact of decriminalization is concentrated amongst minors, who have a higher rate of uptake in the first five years following its introduction.

  10. Does liberalizing cannabis laws increase cannabis use?

    PubMed

    Williams, Jenny; Bretteville-Jensen, Anne Line

    2014-07-01

    A key question in the ongoing policy debate over cannabis' legal status is whether liberalizing cannabis laws leads to an increase in cannabis use. This paper provides new evidence on the impact of a specific type of liberalization, decriminalization, on initiation into cannabis use. Our identification strategy exploits variation in the timing of cannabis policy reforms and our estimation framework marries a difference-in-difference approach with a discrete time duration model. Our results reveal evidence of both heterogeneity and dynamics in the response of cannabis uptake to decriminalization. Overall, we find that the impact of decriminalization is concentrated amongst minors, who have a higher rate of uptake in the first five years following its introduction. PMID:24727348

  11. AKT1 genotype moderates the acute psychotomimetic effects of naturalistically smoked cannabis in young cannabis smokers

    PubMed Central

    Morgan, C J A; Freeman, T P; Powell, J; Curran, H V

    2016-01-01

    Smoking cannabis daily doubles an individual's risk of developing a psychotic disorder, yet indicators of specific vulnerability have proved largely elusive. Genetic variation is one potential risk modifier. Single-nucleotide polymorphisms in the AKT1 and catechol-O-methyltransferase (COMT) genes have been implicated in the interaction between cannabis, psychosis and cognition, but no studies have examined their impact on an individual's acute response to smoked cannabis. A total 442 healthy young cannabis users were tested while intoxicated with their own cannabis—which was analysed for delta-9-tetrahydrocannbinol (THC) and cannabidiol content—and also ±7 days apart when drug-free. Psychotomimetic symptoms and working memory were assessed on both the sessions. Variation at the rs2494732 locus of the AKT1 gene predicted acute psychotic response to cannabis along with dependence on the drug and baseline schizotypal symptoms. Working memory following cannabis acutely was worse in females, with some suggestion of an impact of COMT polymorphism on working memory when drug-free. These findings are the first to demonstrate that AKT1 mediates the acute response to cannabis in otherwise healthy individuals and implicate the AKT1 pathway as a possible target for prevention and treatment of cannabis psychosis. PMID:26882038

  12. Achieving Cannabis Cessation - Evaluating N-acetylcysteine Treatment (ACCENT): Design and implementation of a multi-site, randomized controlled study in the National Institute on Drug Abuse Clinical Trials Network

    PubMed Central

    McClure, Erin A.; Sonne, Susan C.; Winhusen, Theresa; Carroll, Kathleen M.; Ghitza, Udi E.; McRae-Clark, Aimee L.; Matthews, Abigail G.; Sharma, Gaurav; Van Veldhuisen, Paul; Vandrey, Ryan G.; Levin, Frances R.; Weiss, Roger D.; Lindblad, Robert; Allen, Colleen; Mooney, Larissa J.; Haynes, Louise; Brigham, Gregory S.; Sparenborg, Steve; Hasson, Albert L.; Gray, Kevin M.

    2014-01-01

    Despite recent advances in behavioral interventions for cannabis use disorders, effect sizes remain modest, and few individuals achieve long-term abstinence. One strategy to enhance outcomes is the addition of pharmacotherapy to complement behavioral treatment, but to date no efficacious medications targeting cannabis use disorders in adults through large, randomized controlled trials have been identified. The National Institute on Drug Abuse Clinical Trials Network (NIDA CTN) is currently conducting a study to test the efficacy of N-acetylcysteine (NAC) versus placebo (PBO), added to contingency management, for cannabis cessation in adults (ages 18–50). This study was designed to replicate positive findings from a study in cannabis-dependent adolescents that found greater odds of abstinence with NAC compared to PBO. This paper describes the design and implementation of an ongoing 12-week, intent-to-treat, double-blind, randomized, placebo-controlled study with one follow-up visit four weeks post-treatment. Approximately 300 treatment-seeking cannabis-dependent adults will be randomized to NAC or PBO across six study sites in the United States. The primary objective of this 12-week study is to evaluate the efficacy of twice-daily orally-administered NAC (1200 mg) versus matched PBO, added to contingency management, on cannabis abstinence. NAC is among the first medications to demonstrate increased odds of abstinence in a randomized controlled study among cannabis users in any age group. The current study will assess the cannabis cessation efficacy of NAC combined with a behavioral intervention in adults, providing a novel and timely contribution to the evidence base for the treatment of cannabis use disorders. PMID:25179587

  13. Achieving cannabis cessation -- evaluating N-acetylcysteine treatment (ACCENT): design and implementation of a multi-site, randomized controlled study in the National Institute on Drug Abuse Clinical Trials Network.

    PubMed

    McClure, Erin A; Sonne, Susan C; Winhusen, Theresa; Carroll, Kathleen M; Ghitza, Udi E; McRae-Clark, Aimee L; Matthews, Abigail G; Sharma, Gaurav; Van Veldhuisen, Paul; Vandrey, Ryan G; Levin, Frances R; Weiss, Roger D; Lindblad, Robert; Allen, Colleen; Mooney, Larissa J; Haynes, Louise; Brigham, Gregory S; Sparenborg, Steve; Hasson, Albert L; Gray, Kevin M

    2014-11-01

    Despite recent advances in behavioral interventions for cannabis use disorders, effect sizes remain modest, and few individuals achieve long-term abstinence. One strategy to enhance outcomes is the addition of pharmacotherapy to complement behavioral treatment, but to date no efficacious medications targeting cannabis use disorders in adults through large, randomized controlled trials have been identified. The National Institute on Drug Abuse Clinical Trials Network (NIDA CTN) is currently conducting a study to test the efficacy of N-acetylcysteine (NAC) versus placebo (PBO), added to contingency management, for cannabis cessation in adults (ages 18-50). This study was designed to replicate positive findings from a study in cannabis-dependent adolescents that found greater odds of abstinence with NAC compared to PBO. This paper describes the design and implementation of an ongoing 12-week, intent-to-treat, double-blind, randomized, placebo-controlled study with one follow-up visit four weeks post-treatment. Approximately 300 treatment-seeking cannabis-dependent adults will be randomized to NAC or PBO across six study sites in the United States. The primary objective of this 12-week study is to evaluate the efficacy of twice-daily orally-administered NAC (1200 mg) versus matched PBO, added to contingency management, on cannabis abstinence. NAC is among the first medications to demonstrate increased odds of abstinence in a randomized controlled study among cannabis users in any age group. The current study will assess the cannabis cessation efficacy of NAC combined with a behavioral intervention in adults, providing a novel and timely contribution to the evidence base for the treatment of cannabis use disorders.

  14. Residual cannabis levels in blood, urine and oral fluid following heavy cannabis use.

    PubMed

    Odell, Morris S; Frei, Matthew Y; Gerostamoulos, Dimitri; Chu, Mark; Lubman, Dan I

    2015-04-01

    An understanding of tetrahydrocannabinol (THC) kinetics and residual levels after cannabis use is essential in interpreting toxicology tests in body fluids from live subjects, particularly when used in forensic settings for drug abuse, traffic and interpersonal violence cases. However the current literature is largely based on laboratory studies using controlled cannabis dosages in experienced users, with limited research investigating the kinetics of residual THC concentrations in regular high dose cannabis users. Twenty-one dependent cannabis users were recruited at admission to two residential detoxification units in Melbourne, Australia. After being provided with information about, and consenting to, the study, subjects volunteered to provide once-daily blood, urine and oral fluid (saliva) samples for seven consecutive days following admission, involving cessation and abstinence from all cannabis use. Blood and oral fluid specimens were analysed for THC and urine specimens for the metabolite THC-COOH. In some subjects THC was detectable in blood for at least 7 days and oral fluid specimens were positive for THC up to 78 h after admission to the unit. Urinary THC-COOH concentrations exceeded 1000 ng/mL for some subjects 129 h after last use. The presented blood THC levels are higher and persist longer in some individuals than previously described, our understanding and interpretation of THC levels in long term heavy cannabis users may need to be reconsidered. PMID:25698515

  15. Acute effects of cannabis on breath-holding duration.

    PubMed

    Farris, Samantha G; Metrik, Jane

    2016-08-01

    Distress intolerance (an individual's perceived or actual inability to tolerate distressing psychological or physiological states) is associated with cannabis use. It is unknown whether a biobehavioral index of distress intolerance, breath-holding duration, is acutely influenced (increased or decreased) by cannabis. Such information may further inform understanding of the expression of psychological or physiological distress postcannabis use. This within-subjects study examined whether smoked marijuana with 2.7%-3.0% delta-9-tetrahydrocannabinol (THC), relative to placebo, acutely changed duration of breath holding. Participants (n = 88; 65.9% male) were nontreatment-seeking frequent cannabis users who smoked placebo or active THC cigarette on two separate study days and completed a breath-holding task postsmoking. Controlling for baseline breath-holding duration and participant sex, THC produced significantly shorter breath-holding durations relative to placebo. There was a significant interaction of drug administration × frequency of cannabis use, such that THC decreased breath-holding time among less frequent but not among more frequent users. Findings indicate that cannabis may exacerbate distress intolerance (via shorter breath-holding durations). As compared to less frequent cannabis users, frequent users display tolerance to cannabis' acute effects including increased ability to tolerate respiratory distress when holding breath. Objective measures of distress intolerance are sensitive to contextual factors such as acute drug intoxication, and may inform the link between cannabis use and the expression of psychological distress. (PsycINFO Database Record PMID:27454678

  16. Cannabis Use and Related Harms in the Transition to Young Adulthood: A Longitudinal Study of Australian Secondary School Students

    ERIC Educational Resources Information Center

    Scholes-Balog, Kirsty E.; Hemphill, Sheryl A.; Patton, George C.; Toumbourou, John W.

    2013-01-01

    The current study documents the changing rates of cannabis use, misuse and cannabis-related social harms among Australian adolescents as they grow into young adulthood. It utilised data from a longitudinal study of young people at ages 15, 16, 17, and 19. The rates of cannabis use were found to increase as participants aged; past year use…

  17. General and oral health implications of cannabis use.

    PubMed

    Cho, C M; Hirsch, R; Johnstone, S

    2005-06-01

    Cannabis, commonly known as marijuana, is the most frequently used illicit drug in Australia. Therefore, oral health care providers are likely to encounter patients who are regular users. An upward trend in cannabis use is occurring in Australia, with 40 per cent of the population aged 14 and above having used the drug. There are three main forms of cannabis: marijuana, hash and hash oil, all of which contain the main psychoactive constituent delta-9-tetrahydrocannabinol (THC). Cannabis is most commonly smoked, however it can be added to foods. THC from cannabis enters the bloodstream and exerts its effects on the body via interaction with endogenous receptors. Cannabis affects almost every system of the body, particularly the cardiovascular, respiratory and immune systems. It also has acute and chronic effects on the mental health of some users. Therefore, chronic abuse is a concern because of its negative effects on general physical and mental health. Cannabis abusers generally have poorer oral health than non-users, with an increased risk of dental caries and periodontal diseases. Cannabis smoke acts as a carcinogen and is associated with dysplastic changes and pre-malignant lesions within the oral mucosa. Users are also prone to oral infections, possibly due to the immunosuppressive effects. Dental treatment on patients intoxicated on cannabis can result in the patient experiencing acute anxiety, dysphoria and psychotic-like paranoiac thoughts. The use of local anaesthetic containing epinephrine may seriously prolong tachycardia already induced by an acute dose of cannabis. Oral health care providers should be aware of the diverse adverse effects of cannabis on general and oral health and incorporate questions about patients' patterns of use in the medical history.

  18. Genetic predisposition to schizophrenia associated with increased use of cannabis.

    PubMed

    Power, R A; Verweij, K J H; Zuhair, M; Montgomery, G W; Henders, A K; Heath, A C; Madden, P A F; Medland, S E; Wray, N R; Martin, N G

    2014-11-01

    Cannabis is the most commonly used illicit drug worldwide. With debate surrounding the legalization and control of use, investigating its health risks has become a pressing area of research. One established association is that between cannabis use and schizophrenia, a debilitating psychiatric disorder affecting ~1% of the population over their lifetime. Although considerable evidence implicates cannabis use as a component cause of schizophrenia, it remains unclear whether this is entirely due to cannabis directly raising risk of psychosis, or whether the same genes that increases psychosis risk may also increase risk of cannabis use. In a sample of 2082 healthy individuals, we show an association between an individual's burden of schizophrenia risk alleles and use of cannabis. This was significant both for comparing those who have ever versus never used cannabis (P=2.6 × 10(-4)), and for quantity of use within users (P=3.0 × 10(-3)). Although directly predicting only a small amount of the variance in cannabis use, these findings suggest that part of the association between schizophrenia and cannabis is due to a shared genetic aetiology. This form of gene-environment correlation is an important consideration when calculating the impact of environmental risk factors, including cannabis use. PMID:24957864

  19. Antianxiety effect of cannabis: involvement of central benzodiazepine receptors.

    PubMed

    Sethi, B B; Trivedi, J K; Kumar, P; Gulati, A; Agarwal, A K; Sethi, N

    1986-01-01

    The present work, involving clinical, behavioral, and biochemical studies, was undertaken to elucidate the probable mechanism of the observed antianxiety effects of cannabis. The population for the clinical study consisted of 50 male chronic cannabis users who were otherwise healthy and 50 matched controls. When evaluated on Taylor's Manifest Anxiety Scale (TMA), these subjects had low anxiety scores as compared with the controls. To explore the possible interaction of cannabis with the benzodiazepine receptors, behavioral and biochemical studies in mice were devised, involving acute and chronic cannabis administration. Behavioral study revealed that mice under chronic cannabis treatment scored significantly higher on foot shock-induced aggression, but this was significantly blocked by benzodiazepine receptor antagonist. Furthermore, chronic cannabis treatment significantly (p less than 0.001) increased the frequency of licking response periodically punished by shocks. This confirms the antianxiety effect of cannabis, which also appears to be mediated through a benzodiazepine receptor, as it was reduced significantly (p less than 0.001) by a benzodiazepine receptor blocker. Specific 3H-diazepam binding was carried out in frontal cortex to assess both the population and affinity of benzodiazepine receptors. Our results indicate that acute cannabis treatment has no significant effect, whereas chronic cannabis treatment significantly increased 3H-diazepam binding as compared with controls. Scatchard analysis further reveals that increased affinity is responsible for increased binding to these receptors. It is therefore our contention that the antianxiety effect of cannabis is mediated through central benzodiazepine receptors.

  20. Cannabis use in HIV for pain and other medical symptoms.

    PubMed

    Woolridge, Emily; Barton, Simon; Samuel, Jonathon; Osorio, Jess; Dougherty, Andrew; Holdcroft, Anita

    2005-04-01

    Despite the major benefits of antiretroviral therapy on survival during HIV infection, there is an increasing need to manage symptoms and side effects during long-term drug therapy. Cannabis has been reported anecdotally as being beneficial for a number of common symptoms and complications in HIV infections, for example, poor appetite and neuropathy. This study aimed to investigate symptom management with cannabis. Following Ethics Committee approval, HIV-positive individuals attending a large clinic were recruited into an anonymous cross-sectional questionnaire study. Up to one-third (27%, 143/523) reported using cannabis for treating symptoms. Patients reported improved appetite (97%), muscle pain (94%), nausea (93%), anxiety (93%), nerve pain (90%), depression (86%), and paresthesia (85%). Many cannabis users (47%) reported associated memory deterioration. Symptom control using cannabis is widespread in HIV outpatients. A large number of patients reported that cannabis improved symptom control.

  1. Predicting resistance to health education messages for cannabis use: the role of rebelliousness, autic mastery, health value and ethnicity.

    PubMed

    Boddington, Ellen L; McDermott, Mark R

    2013-02-01

    The prevalent use of cannabis by adolescents and young adults, combined with the common misconception that smoking cannabis is relatively harmless, warrants the exploration of factors influencing resistance to health education messages about cannabis use. This investigation did so within a Reversal Theory framework. One hundred and thirteen undergraduate students responded to an informative leaflet detailing the health effects of smoking cannabis. The most significant independent predictor of message resistance was frequency of cannabis use, followed by proactive rebelliousness, autic mastery, health value and ethnicity. These findings have implications for the development, design and targeting of cannabis health education programmes. PMID:22459759

  2. Long-term effects of cannabis on brain structure.

    PubMed

    Battistella, Giovanni; Fornari, Eleonora; Annoni, Jean-Marie; Chtioui, Haithem; Dao, Kim; Fabritius, Marie; Favrat, Bernard; Mall, Jean-Frédéric; Maeder, Philippe; Giroud, Christian

    2014-08-01

    The dose-dependent toxicity of the main psychoactive component of cannabis in brain regions rich in cannabinoid CB1 receptors is well known in animal studies. However, research in humans does not show common findings across studies regarding the brain regions that are affected after long-term exposure to cannabis. In the present study, we investigate (using Voxel-based Morphometry) gray matter changes in a group of regular cannabis smokers in comparison with a group of occasional smokers matched by the years of cannabis use. We provide evidence that regular cannabis use is associated with gray matter volume reduction in the medial temporal cortex, temporal pole, parahippocampal gyrus, insula, and orbitofrontal cortex; these regions are rich in cannabinoid CB1 receptors and functionally associated with motivational, emotional, and affective processing. Furthermore, these changes correlate with the frequency of cannabis use in the 3 months before inclusion in the study. The age of onset of drug use also influences the magnitude of these changes. Significant gray matter volume reduction could result either from heavy consumption unrelated to the age of onset or instead from recreational cannabis use initiated at an adolescent age. In contrast, the larger gray matter volume detected in the cerebellum of regular smokers without any correlation with the monthly consumption of cannabis may be related to developmental (ontogenic) processes that occur in adolescence.

  3. Long-term effects of cannabis on brain structure.

    PubMed

    Battistella, Giovanni; Fornari, Eleonora; Annoni, Jean-Marie; Chtioui, Haithem; Dao, Kim; Fabritius, Marie; Favrat, Bernard; Mall, Jean-Frédéric; Maeder, Philippe; Giroud, Christian

    2014-08-01

    The dose-dependent toxicity of the main psychoactive component of cannabis in brain regions rich in cannabinoid CB1 receptors is well known in animal studies. However, research in humans does not show common findings across studies regarding the brain regions that are affected after long-term exposure to cannabis. In the present study, we investigate (using Voxel-based Morphometry) gray matter changes in a group of regular cannabis smokers in comparison with a group of occasional smokers matched by the years of cannabis use. We provide evidence that regular cannabis use is associated with gray matter volume reduction in the medial temporal cortex, temporal pole, parahippocampal gyrus, insula, and orbitofrontal cortex; these regions are rich in cannabinoid CB1 receptors and functionally associated with motivational, emotional, and affective processing. Furthermore, these changes correlate with the frequency of cannabis use in the 3 months before inclusion in the study. The age of onset of drug use also influences the magnitude of these changes. Significant gray matter volume reduction could result either from heavy consumption unrelated to the age of onset or instead from recreational cannabis use initiated at an adolescent age. In contrast, the larger gray matter volume detected in the cerebellum of regular smokers without any correlation with the monthly consumption of cannabis may be related to developmental (ontogenic) processes that occur in adolescence. PMID:24633558

  4. Cannabis: its therapeutic use.

    PubMed

    Wall, J; Davis, S; Ridgway, S

    This article provides an overview of the issues surrounding the use of cannabis for therapeutic purposes. Examples of some of the ethical issues related to professional practice are discussed. The authors do not advocate legalising cannabis for all, but the therapeutic advantages and disadvantages of using cannabis are highlighted.

  5. Risk perceptions of smokeless tobacco among adolescents and adult users and nonusers

    PubMed Central

    Liu, Sherry T.; Nemeth, Julianna M.; Klein, Elizabeth G.; Ferketich, Amy K.; Kwan, Mei-Po; Wewers, Mary Ellen

    2015-01-01

    The recent growth in smokeless tobacco (ST) consumption has raised questions about consumer risk perceptions of ST products, especially in high-risk vulnerable populations. This qualitative study examined risk perceptions of ST among adolescent and adult users and non-users in Ohio Appalachia. Focus groups and interviews were held with adolescents (n=53; mean age of 17 years) and adults (n=63; mean age of 34 years) from four Ohio Appalachian counties. Participants were asked about their perceptions of ST-related health risks, ST safety, and the relative safety of ST compared to cigarettes. Transcriptions were coded independently by two individuals. Overall, participants were knowledgeable about health problems from ST use (e.g., oral cancers, periodontal disease). Nearly all participants stated that ST use is not safe; however, there was disagreement about its relative safety. Some perceived all tobacco products as equally harmful; others believed that ST is safer than cigarettes for either the user or those around the user. Disagreements about ST relative safety may reflect mixed public health messages concerning the safety of ST. Comprehensive consumer messages about the relative safety of ST compared to cigarettes are needed. Messages should address the effect of ST on the health of the user as well as those exposed to the user. PMID:25832126

  6. [Cannabis use and risk of psychosis, an etiological link?].

    PubMed

    Verdoux, Hélène; Tournier, Marie

    2004-04-24

    CANNABIS TO TREAT PSYCHOSIS: The nature of the link between cannabis use and psychosis remains to be clarified. Cross-sectional epidemiological studies have shown that individuals with psychosis use cannabis more often than other individuals in the general population. It has long been considered that this association was explained by the self-medication hypothesis, postulating that cannabis is used to self-medicate psychotic symptoms. This hypothesis has been recently challenged. PSYCHOTIC DISORDERS ENHANCED BY CANNABIS: Several prospective studies carried out in population-based samples, showed that cannabis exposure was associated with an increased risk of psychosis. A dose-response relationship was found between cannabis exposure and risk of psychosis, and this association was independent from potential confounding factors such as exposure to other drugs and pre-existence of psychotic symptoms. The brain mechanisms underlying the association have to be elucidated; they may implicate deregulation of cannabinoid and dopaminergic systems. A RISK FACTOR NOT TO BE NEGLECTED: Cannabis exposure may be a risk factor for psychotic disorders by interacting with a pre-existing vulnerability for these disorders. If further studies confirm that cannabis is a risk factor for psychosis, its impact on the population's mental health may not be negligible considering the growing number of adolescents exposed to this substance.

  7. Analysis of cannabis seizures in NSW, Australia: cannabis potency and cannabinoid profile.

    PubMed

    Swift, Wendy; Wong, Alex; Li, Kong M; Arnold, Jonathon C; McGregor, Iain S

    2013-01-01

    Recent analysis of the cannabinoid content of cannabis plants suggests a shift towards use of high potency plant material with high levels of Δ(9)-tetrahydrocannabinol (THC) and low levels of other phytocannabinoids, particularly cannabidiol (CBD). Use of this type of cannabis is thought by some to predispose to greater adverse outcomes on mental health and fewer therapeutic benefits. Australia has one of the highest per capita rates of cannabis use in the world yet there has been no previous systematic analysis of the cannabis being used. In the present study we examined the cannabinoid content of 206 cannabis samples that had been confiscated by police from recreational users holding 15 g of cannabis or less, under the New South Wales "Cannabis Cautioning" scheme. A further 26 "Known Provenance" samples were analysed that had been seized by police from larger indoor or outdoor cultivation sites rather than from street level users. An HPLC method was used to determine the content of 9 cannabinoids: THC, CBD, cannabigerol (CBG), and their plant-based carboxylic acid precursors THC-A, CBD-A and CBG-A, as well as cannabichromene (CBC), cannabinol (CBN) and tetrahydrocannabivarin (THC-V). The "Cannabis Cautioning" samples showed high mean THC content (THC+THC-A = 14.88%) and low mean CBD content (CBD+CBD-A = 0.14%). A modest level of CBG was detected (CBG+CBG-A = 1.18%) and very low levels of CBC, CBN and THC-V (<0.1%). "Known Provenance" samples showed no significant differences in THC content between those seized from indoor versus outdoor cultivation sites. The present analysis echoes trends reported in other countries towards the use of high potency cannabis with very low CBD content. The implications for public health outcomes and harm reduction strategies are discussed.

  8. Relationship between cannabis and psychosis: Reasons for use and associated clinical variables.

    PubMed

    Mané, Anna; Fernández-Expósito, Miguel; Bergé, Daniel; Gómez-Pérez, Laura; Sabaté, Agnés; Toll, Alba; Diaz, Laura; Diez-Aja, Cristobal; Perez, Victor

    2015-09-30

    The mechanism underneath the relationship between cannabis and psychosis remains controversial, for which several hypotheses have been proposed, including cannabis as self-medication and cannabis as a risk for the development of psychosis. The aim of this work was to study the relationship between cannabis and psychosis in first-episode psychosis cannabis users and non-users, and non-psychotic cannabis users. The age at the first psychotic episode, duration of untreated psychosis, psychopathology and reasons for cannabis use were assessed. First-episode psychosis cannabis users showed an earlier age at psychosis onset than non-user patients. No significant differences in symptomatology were found. The distinguishing reasons to use cannabis for patients with first-episode psychosis with respect to non-psychotic users were to arrange their thoughts and deal with hallucinations and suspiciousness. These findings are in agreement with both hypotheses: self-medication and secondary psychosis hypothesis. However, longitudinal prospective cohort studies assessing reasons for cannabis use are needed to investigate both hypotheses and their complementarity.

  9. Who is using cannabis as a medicine and why: an exploratory study.

    PubMed

    Ogborne, A C; Smart, R G; Weber, T; Birchmore-Timney, C

    2000-01-01

    This article reports on an exploratory study of medical cannabis users. Interviews were completed with 50 self-identified medical cannabis users recruited through notices in newspapers and on bulletin boards. They reported using cannabis for a variety of conditions including HIV-AIDS-related problems, chronic pain, depression, anxiety, menstrual cramps, migraine, narcotic addiction as well as everyday aches, pains, stresses and sleeping difficulties. A majority also used cannabis for recreational purposes, and many were longer-term cannabis users. However, there were some notable exceptions. Almost all smoked cannabis and many did so two to three times a day. Few admitted negative experiences with cannabis, although some problems evident to the researchers were not clearly admitted. Those who told their doctors about their medical cannabis use found doctors noncommittal or supportive. The results raise questions about the definition of medical cannabis use and about policies that might be developed to accommodate such use. Limitations of the study are noted and further research suggested. Research priorities include population surveys, studies involving larger, more representative samples of medical cannabis users and studies of medical cannabis use among people with HIV-AIDS.

  10. Who is using cannabis as a medicine and why: an exploratory study.

    PubMed

    Ogborne, A C; Smart, R G; Weber, T; Birchmore-Timney, C

    2000-01-01

    This article reports on an exploratory study of medical cannabis users. Interviews were completed with 50 self-identified medical cannabis users recruited through notices in newspapers and on bulletin boards. They reported using cannabis for a variety of conditions including HIV-AIDS-related problems, chronic pain, depression, anxiety, menstrual cramps, migraine, narcotic addiction as well as everyday aches, pains, stresses and sleeping difficulties. A majority also used cannabis for recreational purposes, and many were longer-term cannabis users. However, there were some notable exceptions. Almost all smoked cannabis and many did so two to three times a day. Few admitted negative experiences with cannabis, although some problems evident to the researchers were not clearly admitted. Those who told their doctors about their medical cannabis use found doctors noncommittal or supportive. The results raise questions about the definition of medical cannabis use and about policies that might be developed to accommodate such use. Limitations of the study are noted and further research suggested. Research priorities include population surveys, studies involving larger, more representative samples of medical cannabis users and studies of medical cannabis use among people with HIV-AIDS. PMID:11210205

  11. [Cannabis and psychosis].

    PubMed

    Curtis, L; Rey-Bellet, P; Merlo, M C G

    2006-09-20

    Cannabis is abused by a progressively larger and younger proportion of our population. For the clinician, this can raise the question of what the relationship between cannabis and psychosis is. For the patient who is already psychotic, this relationship is most certainly adverse; cannabis worsens the symptoms and prognosis of a psychosis. What may be of even greater concern is the growing evidence that cannabis may cause psychosis in healthy individuals. Many studies now show a robust and consistent association between cannabis consumption and the ulterior development of psychosis. Furthermore, our better understanding of cannabis biology allows the proposal of a plausible hypothetical model, based notably on possible interactions between cannabis and dopaminergic neurotransmission.

  12. Cannabis and breastfeeding.

    PubMed

    Garry, Aurélia; Rigourd, Virginie; Amirouche, Ammar; Fauroux, Valérie; Aubry, Sylvie; Serreau, Raphaël

    2009-01-01

    Cannabis is a drug derived from hemp plant, Cannabis sativa, used both as a recreational drug or as medicine. It is a widespread illegal substance, generally smoked for its hallucinogenic properties. Little is known about the adverse effects of postnatal cannabis exposure throw breastfeeding because of a lack of studies in lactating women. The active substance of cannabis is the delta 9 TetraHydroCannabinol (THC). Some studies conclude that it could decrease motor development of the child at one year of age. Therefore, cannabis use and abuse of other drugs like alcohol, tobacco, or cocaine must be contraindicated during breastfeeding. Mothers who use cannabis must stop breastfeeding, or ask for medical assistance to stop cannabis use in order to provide her baby with all the benefits of human milk.

  13. A comparison of adolescent methamphetamine and other substance users in Hawai'i.

    PubMed

    Kim, Richard J; Jackson, David S

    2008-11-01

    Methamphetamine use continues to be a significant problem for adolescents in Hawai'i, especially among Native Hawaiians and other Asian and Pacific Islanders. However, no research has compared the unique characteristics of these methamphetamine (MA) users to other substance users, which could contribute to enhanced treatment approaches. Utilizing a sample of adolescent treatment clients, this study compared those who have ever used and those who have never used methamphetamines on various domains. Results showed that girls were significantly more likely to use methamphetamines than other substances. Native Hawaiians and other Pacific Islanders were more likely to use methamphetamines as well, although the difference was not statistically significant. MA users reported significantly more homelessness and prior treatment episodes. While no differences were found in arrest rates or days in jail/prison/juvenile detention in the past 90 days, MA users scored significantly higher on all self-reported crime indices. MA users also scored significantly higher on all substance problem and mental health indices, and reported significantly poorer health. Implications for future research and treatment are discussed.

  14. Acute effects of delta-9-tetrahydrocannabinol, cannabidiol and their combination on facial emotion recognition: a randomised, double-blind, placebo-controlled study in cannabis users.

    PubMed

    Hindocha, Chandni; Freeman, Tom P; Schafer, Grainne; Gardener, Chelsea; Das, Ravi K; Morgan, Celia J A; Curran, H Valerie

    2015-03-01

    Acute administration of the primary psychoactive constituent of cannabis, Δ-9-tetrahydrocannabinol (THC), impairs human facial affect recognition, implicating the endocannabinoid system in emotional processing. Another main constituent of cannabis, cannabidiol (CBD), has seemingly opposite functional effects on the brain. This study aimed to determine the effects of THC and CBD, both alone and in combination on emotional facial affect recognition. 48 volunteers, selected for high and low frequency of cannabis use and schizotypy, were administered, THC (8mg), CBD (16mg), THC+CBD (8mg+16mg) and placebo, by inhalation, in a 4-way, double-blind, placebo-controlled crossover design. They completed an emotional facial affect recognition task including fearful, angry, happy, sad, surprise and disgust faces varying in intensity from 20% to 100%. A visual analogue scale (VAS) of feeling 'stoned' was also completed. In comparison to placebo, CBD improved emotional facial affect recognition at 60% emotional intensity; THC was detrimental to the recognition of ambiguous faces of 40% intensity. The combination of THC+CBD produced no impairment. Relative to placebo, both THC alone and combined THC+CBD equally increased feelings of being 'stoned'. CBD did not influence feelings of 'stoned'. No effects of frequency of use or schizotypy were found. In conclusion, CBD improves recognition of emotional facial affect and attenuates the impairment induced by THC. This is the first human study examining the effects of different cannabinoids on emotional processing. It provides preliminary evidence that different pharmacological agents acting upon the endocannabinoid system can both improve and impair recognition of emotional faces.

  15. Cannabis policy in Australia and New Zealand.

    PubMed

    Abel, S

    1997-12-01

    This paper describes and compares current developments in policies to deal with cannabis in Australia and New Zealand. Both countries are bound by international conventions to control cannabis and in each case cannabis use, possession, cultivation and supply is illegal. In both countries almost all the supply is grown locally and patterns of use and health concerns appear to be similar. Strategies used to deal with cannabis include: demand reduction through enforcement of legislation, drug education and treatment; supply reduction through enforcement of legislation and crop recovery operations; and harm reduction through diversion of some offenders from the courts system, lenient enforcement policies for users and, in Australia, the formal decriminalization of cannabis use in two states/territories and de facto decriminalization in another. Australia has had a co-ordinated national drugs policy with a stated harm reduction focus for over a decade, while in New Zealand efforts to co-ordinate policy have been delayed by ongoing debates about cannabis's harm potential and what constitutes an appropriate approach. However, a national drugs policy with a professed harm reduction focus is currently being finalized. Despite these developments, government cut-backs and international and local prohibitionist influences on policy in both countries suggest that a harm reduction model may not necessarily be secure. PMID:16203457

  16. Smoke your troubles away: exploring the effects of death cognitions on cannabis craving and consumption.

    PubMed

    Nagar, Maayan; Rabinovitz, Sharon

    2015-01-01

    Two studies informed by the terror management health model were conducted to examine the question of how death cognition affects cannabis craving and whether actual cannabis smoking alleviates death cognitions. The first study examined whether priming thoughts of death are associated with subjective cannabis craving among 42 frequent cannabis users randomly assigned to either a mortality salience or control task. When reminded of their death, participants craved cannabis, even though there was no change in their conscious negative mood. The second study examined the effect of cannabis smoking on death cognitions in an exploratory field setting. Fifty frequent cannabis users were randomly assigned to either mortality reminders or control task and completed death-related words accessibility measures before and after smoking cannabis. Results indicate that cannabis served as a buffer and prevented death-related thoughts from entering consciousness, thus acting as a defense mechanism against death anxiety. These findings indicate that death-related concerns may play a hitherto unsuspected role in cannabis craving and consumption. Also discussed are the implications of a terror management perspective in communication of negative health consequences of recreational cannabis smoking and in the use of cannabis for medical purposes among people with terminal illness.

  17. Smoke your troubles away: exploring the effects of death cognitions on cannabis craving and consumption.

    PubMed

    Nagar, Maayan; Rabinovitz, Sharon

    2015-01-01

    Two studies informed by the terror management health model were conducted to examine the question of how death cognition affects cannabis craving and whether actual cannabis smoking alleviates death cognitions. The first study examined whether priming thoughts of death are associated with subjective cannabis craving among 42 frequent cannabis users randomly assigned to either a mortality salience or control task. When reminded of their death, participants craved cannabis, even though there was no change in their conscious negative mood. The second study examined the effect of cannabis smoking on death cognitions in an exploratory field setting. Fifty frequent cannabis users were randomly assigned to either mortality reminders or control task and completed death-related words accessibility measures before and after smoking cannabis. Results indicate that cannabis served as a buffer and prevented death-related thoughts from entering consciousness, thus acting as a defense mechanism against death anxiety. These findings indicate that death-related concerns may play a hitherto unsuspected role in cannabis craving and consumption. Also discussed are the implications of a terror management perspective in communication of negative health consequences of recreational cannabis smoking and in the use of cannabis for medical purposes among people with terminal illness. PMID:25950588

  18. Mental Health Characteristics and Health-Seeking Behaviors of Adolescent School-Based Health Center Users and Nonusers

    ERIC Educational Resources Information Center

    Amaral, Gorette; Geierstanger, Sara; Soleimanpour, Samira; Brindis, Claire

    2011-01-01

    Background: The purpose of this study is to compare the mental health risk profile and health utilization behaviors of adolescent school-based health center (SBHC) users and nonusers and discuss the role that SBHCs can play in addressing adolescent health needs. Methods: The sample included 4640 students in grades 9 and 11 who completed the…

  19. Follow-up of adolescent oral contraceptive users.

    PubMed

    Delmore, T; Kalagian, W F; Loewen, I R

    1991-01-01

    Clients in birth control centers (St. Catharines, Niagara Falls, and Welland) in Ontario, Canada were profiled in 1989; factors affecting compliance with the use of oral contraceptives (OCs) were investigated. Compliance was assessed for those 16 years and after 3 months of OC use. A control group and 2 study groups were randomly formed. 1 group was told about a follow up telephone call if the 3-month checkup appointment was not kept and the other not told. Compliance was determined by keeping the follow-up appointment and taking the pill as directed. Self-administered questionnaires were obtained at the 1st appointment and the 2nd study group was interviewed at the 3-month appointment time. Of the 334 intake interviews, 28.4% were adolescents 16 years old. Information on birth control came most frequently from friends (78.7%; then high school classmates, 61.4% grade school classmates, 61.4%; and family, 38.0%). 94.3% had a boyfriend, primarily a steady one. 82.4% were sexually active before the Center visit. 21.3% had had sex when 15 years old. 9.2% of those sexually active had never used birth control. 85.2% of those using contraception had used a condom at least once, and 33.9% used withdrawal. In the preceding month, birth control was used 60% of the time. 46% of mothers and 25% of fathers were considered supportive of birth control. 228 16 years participated in the compliance study. The 2 study groups and the control group were not significantly different in their compliance. The only statistically significant predictor of compliance (from the intake interview) was the previous use of the condom. Those more likely to be compliant were the 10.9% sexually active who had never used a condom. Continuing with the family doctor, not sexually active, advice to stop, side effects concerns, and remembering to take the pill were the most common reasons for noncompliance. The implication for health and sex education is that emphasis needs to the placed on the risks taken

  20. Cannabis smoke condensate II: influence of tobacco on tetrahydrocannabinol levels.

    PubMed

    Van der Kooy, F; Pomahacova, B; Verpoorte, R

    2009-02-01

    Medicinal cannabis has attracted a lot of attention in recent times. Various forms of administration are used, of which smoking is very common but the least desirable. Smoking cannabis generates a large amount of unwanted side products, of which carcinogenic compounds are the most dangerous. A common practice among recreational drug users, and to a lesser degree patients who uses cannabis as medicine, is to mix the cannabis material with commercially available tobacco in order to increase the burning efficiency of the cigarette and to reduce the overall costs of the cigarette. In this study cannabis material has been mixed with tobacco in order to determine whether tobacco has an influence on the amount of and ratio between tetrahydrocannabinol (THC), cannabigerol (CBG), and cannabinol (CBN) administered while smoking. A small-scale smoking machine has been used and cannabis mixed with various ratios of tobacco was smoked. The trapped smoke was quantitatively analyzed by high-performance liquid chromatography (HPLC) and the amount of THC, CBG, and CBN was determined for each cigarette. We have found that tobacco increases the amount of THC inhaled per gram of cannabis from 32.70 +/- 2.29 mg/g for a 100% cannabis cigarette to 58.90 +/- 2.30 mg/g for a 25% cannabis cigarette. This indicates that tobacco increases the vaporization efficiency of THC by as much as 45% under the conditions tested.

  1. Snus user identity and addiction. A Swedish focus group study on adolescents

    PubMed Central

    2012-01-01

    Background The teenage years are the years when adolescents seek their identity, and part of this involves experimenting with tobacco. The use of tobacco as such, and norms among their friends, is more important to the adolescents than the norms of parents when it comes to using tobacco or not. The aim was to explore the significance of using snus for adolescents, and attitudes to snus, as well as the reasons why they began using snus and what maintained and facilitated the use of snus. Methods Adolescents who use snus were interviewed in focus groups. The material was analysed using content analysis. Results Four groups of boys and one group of girls were interviewed, a total of 27 students from the upper secondary vocational program. Three themes related to the students’ opinions on and experiences of using snus were found: Circumstances pertaining to snus debut indicate what makes them start using snus. Upholding, which focuses on the problem of becoming addicted and development of identity, and approach, where the adolescents reflect on their snus habits in relation to those around them. A number of factors were described as relevant to behaviour and norm building for the development into becoming a snus user. Attitudes and actions from adults and friends as well as – for the boys – development of an identity as a man and a craftsman influenced behaviour. Conclusions The results showed that development of identity was of major importance when adolescents start using snus. The adolescents were initially unable to interpret the early symptoms of abstinence problems, but subsequently became well aware of being addicted. Once they were stuck in addiction and in the creation of an image and identity, it was difficult to stop using snus. These factors are important when considering interventions of normative changes and tobacco prevention in schools as well as among parents. PMID:23148521

  2. Prescribing smoked cannabis for chronic noncancer pain

    PubMed Central

    Kahan, Meldon; Srivastava, Anita; Spithoff, Sheryl; Bromley, Lisa

    2014-01-01

    Objective To offer preliminary guidance on prescribing smoked cannabis for chronic pain before the release of formal guidelines. Quality of evidence We reviewed the literature on the analgesic effectiveness of smoked cannabis and the harms of medical and recreational cannabis use. We developed recommendations on indications, contraindications, precautions, and dosing of smoked cannabis, and categorized the recommendations based on levels of evidence. Evidence is mostly level II (well conducted observational studies) and III (expert opinion). Main message Smoked cannabis might be indicated for patients with severe neuropathic pain conditions who have not responded to adequate trials of pharmaceutical cannabinoids and standard analgesics (level II evidence). Smoked cannabis is contraindicated in patients who are 25 years of age or younger (level II evidence); who have a current, past, or strong family history of psychosis (level II evidence); who have a current or past cannabis use disorder (level III evidence); who have a current substance use disorder (level III evidence); who have cardiovascular or respiratory disease (level III evidence); or who are pregnant or planning to become pregnant (level II evidence). It should be used with caution in patients who smoke tobacco (level II evidence), who are at increased risk of cardiovascular disease (level III evidence), who have anxiety or mood disorders (level II evidence), or who are taking higher doses of opioids or benzodiazepines (level III evidence). Cannabis users should be advised not to drive for at least 3 to 4 hours after smoking, for at least 6 hours after oral ingestion, and for at least 8 hours if they experience a subjective “high” (level II evidence). The maximum recommended dose is 1 inhalation 4 times per day (approximately 400 mg per day) of dried cannabis containing 9% delta-9-tetrahydrocannabinol (level III evidence). Physicians should avoid referring patients to “cannabinoid” clinics (level

  3. Pathways from cannabis to psychosis: a review of the evidence.

    PubMed

    Burns, Jonathan K

    2013-01-01

    The nature of the relationship between cannabis use (CU) and psychosis is complex and remains unclear. Researchers and clinicians remain divided regarding key issues such as whether or not cannabis is an independent cause of psychosis and schizophrenia. This paper reviews the field in detail, examining questions of causality, the neurobiological basis for such causality and for differential inter-individual risk, the clinical and cognitive features of psychosis in cannabis users, and patterns of course and outcome of psychosis in the context of CU. The author proposes two major pathways from cannabis to psychosis based on a differentiation between early-initiated lifelong CU and a scenario where vulnerable individuals without a lifelong pattern of use consume cannabis over a relatively brief period of time just prior to psychosis onset. Additional key factors determining the clinical and neurobiological manifestation of psychosis as well as course and outcome in cannabis users include: underlying genetic and developmental vulnerability to schizophrenia-spectrum disorders; and whether or not CU ceases or continues after the onset of psychosis. Finally, methodological guidelines are presented for future research aimed at both elucidating the pathways that lead from cannabis to psychosis and clarifying the long-term outcome of the disorder in those who have a history of using cannabis. PMID:24133460

  4. The pharmacologic and clinical effects of medical cannabis.

    PubMed

    Borgelt, Laura M; Franson, Kari L; Nussbaum, Abraham M; Wang, George S

    2013-02-01

    Cannabis, or marijuana, has been used for medicinal purposes for many years. Several types of cannabinoid medicines are available in the United States and Canada. Dronabinol (schedule III), nabilone (schedule II), and nabiximols (not U.S. Food and Drug Administration approved) are cannabis-derived pharmaceuticals. Medical cannabis or medical marijuana, a leafy plant cultivated for the production of its leaves and flowering tops, is a schedule I drug, but patients obtain it through cannabis dispensaries and statewide programs. The effect that cannabinoid compounds have on the cannabinoid receptors (CB(1) and CB(2) ) found in the brain can create varying pharmacologic responses based on formulation and patient characteristics. The cannabinoid Δ(9) -tetrahydrocannabinol has been determined to have the primary psychoactive effects; the effects of several other key cannabinoid compounds have yet to be fully elucidated. Dronabinol and nabilone are indicated for the treatment of nausea and vomiting associated with cancer chemotherapy and of anorexia associated with weight loss in patients with acquired immune deficiency syndrome. However, pain and muscle spasms are the most common reasons that medical cannabis is being recommended. Studies of medical cannabis show significant improvement in various types of pain and muscle spasticity. Reported adverse effects are typically not serious, with the most common being dizziness. Safety concerns regarding cannabis include the increased risk of developing schizophrenia with adolescent use, impairments in memory and cognition, accidental pediatric ingestions, and lack of safety packaging for medical cannabis formulations. This article will describe the pharmacology of cannabis, effects of various dosage formulations, therapeutics benefits and risks of cannabis for pain and muscle spasm, and safety concerns of medical cannabis use.

  5. The pharmacologic and clinical effects of medical cannabis.

    PubMed

    Borgelt, Laura M; Franson, Kari L; Nussbaum, Abraham M; Wang, George S

    2013-02-01

    Cannabis, or marijuana, has been used for medicinal purposes for many years. Several types of cannabinoid medicines are available in the United States and Canada. Dronabinol (schedule III), nabilone (schedule II), and nabiximols (not U.S. Food and Drug Administration approved) are cannabis-derived pharmaceuticals. Medical cannabis or medical marijuana, a leafy plant cultivated for the production of its leaves and flowering tops, is a schedule I drug, but patients obtain it through cannabis dispensaries and statewide programs. The effect that cannabinoid compounds have on the cannabinoid receptors (CB(1) and CB(2) ) found in the brain can create varying pharmacologic responses based on formulation and patient characteristics. The cannabinoid Δ(9) -tetrahydrocannabinol has been determined to have the primary psychoactive effects; the effects of several other key cannabinoid compounds have yet to be fully elucidated. Dronabinol and nabilone are indicated for the treatment of nausea and vomiting associated with cancer chemotherapy and of anorexia associated with weight loss in patients with acquired immune deficiency syndrome. However, pain and muscle spasms are the most common reasons that medical cannabis is being recommended. Studies of medical cannabis show significant improvement in various types of pain and muscle spasticity. Reported adverse effects are typically not serious, with the most common being dizziness. Safety concerns regarding cannabis include the increased risk of developing schizophrenia with adolescent use, impairments in memory and cognition, accidental pediatric ingestions, and lack of safety packaging for medical cannabis formulations. This article will describe the pharmacology of cannabis, effects of various dosage formulations, therapeutics benefits and risks of cannabis for pain and muscle spasm, and safety concerns of medical cannabis use. PMID:23386598

  6. Clinical Correlates of Co-Occurring Cannabis and Tobacco Use: A Systematic Review

    PubMed Central

    Peters, Erica N.; Budney, Alan J.; Carroll, Kathleen M.

    2012-01-01

    Aims A growing literature has documented the substantial prevalence of and putative mechanisms underlying co-occurring (i.e., concurrent or simultaneous) cannabis and tobacco use. Greater understanding of the clinical correlates of co-occurring cannabis and tobacco use may suggest how intervention strategies may be refined to improve cessation outcomes and decrease the public health burden associated with cannabis and tobacco use. Methods A systematic review of the literature on clinical diagnoses, psychosocial problems, and outcomes associated with co-occurring cannabis and tobacco use. Twenty-eight studies compared clinical correlates in co-occurring cannabis and tobacco users vs. cannabis or tobacco only users. These included studies of treatment-seekers in clinical trials and non-treatment-seekers in cross-sectional or longitudinal epidemiological or non-population-based surveys. Results Sixteen studies examined clinical diagnoses, four studies examined psychosocial problems, and 11 studies examined cessation outcomes in co-occurring cannabis and tobacco users (several studies examined multiple clinical correlates). Relative to cannabis use only, co-occurring cannabis and tobacco use was associated with a greater likelihood of cannabis use disorders, more psychosocial problems, and poorer cannabis cessation outcomes. Relative to tobacco use only, co-occurring use did not appear to be consistently associated with a greater likelihood of tobacco use disorders, more psychosocial problems, nor poorer tobacco cessation outcomes. Conclusions Cannabis users who also smoke tobacco are more dependent on cannabis, have more psychosocial problems, and have poorer cessation outcomes than those who use cannabis but not tobacco. The converse does not appear to be the case. PMID:22340422

  7. The role of decision-making in cannabis-related problems among young adults

    PubMed Central

    Gonzalez, Raul; Schuster, Randi M.; Mermelstein, Robin M.; Diviak, Kathleen R.

    2015-01-01

    Background Deficits in decision-making and episodic memory are often reported among heavy cannabis users, yet little is known on how they influence negative consequences from cannabis use. Individual differences in decision-making may explain, in part, why some individuals experience significant problems from their cannabis use whereas others do not. We hypothesized that poor decision-making would moderate relationships between amount of cannabis use and problems from cannabis use whereas episodic memory performance would not. Method Young adult cannabis users (n = 52) with cannabis as their drug of choice and with minimal comorbidities completed semi-structured interviews, self-report questionnaires, and measures of neurocognitive functioning, with decision-making accessed via the Iowa Gambling Task (IGT), episodic memory via the Hopkins Verbal Learning Test – Revised (HVLT) and problems from cannabis use with the Marijuana Problems Scale. Results Strong relationships were observed between amount of cannabis use (lifetime, 12-month, and 30-day) and problems reported from use, but only among participants with Low (impaired) decision-making (R2 = .39 to .51; p < .01). No significant relationships were observed among those with better (low average to high average) decision-making performance (p > .05). In contrast, episodic memory performance was not a significant moderator of the relationship between amount of cannabis use and cannabis problems (p > .05). Conclusions Cannabis users with poor decision-making may be at greater risk for experiencing significant negative consequences from their cannabis use. Our results lend further support to emerging evidence of decision-making as a risk factor for addiction and extend these findings to cannabis users. PMID:26199058

  8. An Event-Related Potential Study on the Effects of Cannabis on Emotion Processing.

    PubMed

    Troup, Lucy J; Bastidas, Stephanie; Nguyen, Maia T; Andrzejewski, Jeremy A; Bowers, Matthew; Nomi, Jason S

    2016-01-01

    The effect of cannabis on emotional processing was investigated using event-related potential paradigms (ERPs). ERPs associated with emotional processing of cannabis users, and non-using controls, were recorded and compared during an implicit and explicit emotional expression recognition and empathy task. Comparisons in P3 component mean amplitudes were made between cannabis users and controls. Results showed a significant decrease in the P3 amplitude in cannabis users compared to controls. Specifically, cannabis users showed reduced P3 amplitudes for implicit compared to explicit processing over centro-parietal sites which reversed, and was enhanced, at fronto-central sites. Cannabis users also showed a decreased P3 to happy faces, with an increase to angry faces, compared to controls. These effects appear to increase with those participants that self-reported the highest levels of cannabis consumption. Those cannabis users with the greatest consumption rates showed the largest P3 deficits for explicit processing and negative emotions. These data suggest that there is a complex relationship between cannabis consumption and emotion processing that appears to be modulated by attention. PMID:26926868

  9. An Event-Related Potential Study on the Effects of Cannabis on Emotion Processing.

    PubMed

    Troup, Lucy J; Bastidas, Stephanie; Nguyen, Maia T; Andrzejewski, Jeremy A; Bowers, Matthew; Nomi, Jason S

    2016-01-01

    The effect of cannabis on emotional processing was investigated using event-related potential paradigms (ERPs). ERPs associated with emotional processing of cannabis users, and non-using controls, were recorded and compared during an implicit and explicit emotional expression recognition and empathy task. Comparisons in P3 component mean amplitudes were made between cannabis users and controls. Results showed a significant decrease in the P3 amplitude in cannabis users compared to controls. Specifically, cannabis users showed reduced P3 amplitudes for implicit compared to explicit processing over centro-parietal sites which reversed, and was enhanced, at fronto-central sites. Cannabis users also showed a decreased P3 to happy faces, with an increase to angry faces, compared to controls. These effects appear to increase with those participants that self-reported the highest levels of cannabis consumption. Those cannabis users with the greatest consumption rates showed the largest P3 deficits for explicit processing and negative emotions. These data suggest that there is a complex relationship between cannabis consumption and emotion processing that appears to be modulated by attention.

  10. An Event-Related Potential Study on the Effects of Cannabis on Emotion Processing

    PubMed Central

    Troup, Lucy J.; Bastidas, Stephanie; Nguyen, Maia T.; Andrzejewski, Jeremy A.; Bowers, Matthew; Nomi, Jason S.

    2016-01-01

    The effect of cannabis on emotional processing was investigated using event-related potential paradigms (ERPs). ERPs associated with emotional processing of cannabis users, and non-using controls, were recorded and compared during an implicit and explicit emotional expression recognition and empathy task. Comparisons in P3 component mean amplitudes were made between cannabis users and controls. Results showed a significant decrease in the P3 amplitude in cannabis users compared to controls. Specifically, cannabis users showed reduced P3 amplitudes for implicit compared to explicit processing over centro-parietal sites which reversed, and was enhanced, at fronto-central sites. Cannabis users also showed a decreased P3 to happy faces, with an increase to angry faces, compared to controls. These effects appear to increase with those participants that self-reported the highest levels of cannabis consumption. Those cannabis users with the greatest consumption rates showed the largest P3 deficits for explicit processing and negative emotions. These data suggest that there is a complex relationship between cannabis consumption and emotion processing that appears to be modulated by attention. PMID:26926868

  11. A Statewide Profile of Frequent Users of School-Based Health Centers: Implications for Adolescent Health Care

    ERIC Educational Resources Information Center

    Koenig, Kevin T.; Ramos, Mary M.; Fowler, Tara T.; Oreskovich, Kristin; McGrath, Jane; Fairbrother, Gerry

    2016-01-01

    Background: The purpose of this study is to describe patterns of care and service use among adolescent school-based health center (SBHC) users in New Mexico and contrast patterns and services between frequent and infrequent users. Methods: Medical claims/encounter data were analyzed from 59 SBHCs located in secondary schools in New Mexico during…

  12. The effect of design on the usability and real world effectiveness of medical devices: a case study with adolescent users.

    PubMed

    Lang, Alexandra R; Martin, Jennifer L; Sharples, Sarah; Crowe, John A

    2013-09-01

    Adolescents are currently overlooked in many fields of healthcare research and as a result are often required to use medical devices that have been designed for use by either children or adults. This can lead to poor adherence and a reduction in health outcomes. This study examines the role of device design in the real-world effectiveness of a medical device used in the treatment of cystic fibrosis from the perspective of adolescent users. Interactive design interviews were carried out with 20 adolescent users of the acapella(®) physiotherapy device to investigate user requirements and themes about the user-device relationship that are important to this user group. This study found that adolescent users of the acapella(®) device do not use the device as regularly and correctly as is recommended by clinicians. A number of aspects of the current design of the acapella(®) device were identified that affect how and how often it is used. Five factors are identified that may improve the real world effectiveness of the acapella(®) device for adolescents with Cystic Fibrosis: engagement, information, confidence, aesthetics and compatibility with lifestyle. PMID:23453773

  13. [Methamphetamine, cannabis].

    PubMed

    Naruse, Nobuya

    2015-09-01

    The persons with marijuana abuse tend to be increasing in Japan, although illegal drugs use in lifetime is remarkably lower than other advanced countries, Europe and USA. In addition, there have been many methamphetamine users in Japan. As use of methamphetamine induces psychotic states, we recognize them as one of the key illegal drugs for clinical psychiatrists. Regarding to diagnosis of methamphetamine psychosis, there is a large difference between Japanese psychiatrists and other advanced countries' ones. The former considers that they have persistent symptoms. In contrast, the latter embraces it as the model of acute toxicosis. The Japanese government has been based on a full commitment to the crackdown on drug problems. However, they will execute the new law in 2016, in which some persons charged with violating the methamphetamine control law will be adapted to partially probation on drug charges. Then, we have to improve our therapeutic and recovery supports to charged illegal drug users as rapidly as possible.

  14. Cannabis-Related treatment demands in Belgium: a socio-demographic and treatment seeking profile

    PubMed Central

    2010-01-01

    Aims Most people appear to stop using cannabis when getting older, but a certain subgroup becomes cannabis dependent, has problems in various life areas and needs treatment. Our aim is to compare a number of sociodemographic and treatment seeking variables between treatment seekers with primary cannabis problems and those with primary alcohol, opiate, amphetamine or cocaine problems. Understanding how primary canna-bis users seeking treatment differ from other treatment seekers may assist clinicians in better tailoring treatment processes to clients' needs. Methods For this purpose, intake information on 1,626 persons seeking treatment in one of 16 treat-ment agencies in the province of Antwerp (Belgium) was registered via an on-line web application. Primary cannabis users seeking treatment were compared with primary alcohol, opiate, amphetamine and cocaine users by means of bivariate analyses (Chi-square tests and analyses of variance), followed by four logistic regression analyses. Findings 14.5% of all clients used cannabis as their primary drug. Compared to primary alcohol, opiate, amphetamine or cocaine users seeking treatment, cannabis users seeking treatment appeared to be more often male, younger than 30 years old, Belgian and student. They are often referred to treatment by police or justice and 43.6% of them can be considered single-substance users. Multivariate analyses showed that besides age and sex, using no other substances than the primary drug and being registered in outpatient facilities only were significant determinants for being a primary cannabis user seeking treatment. Conclusions Primary cannabis users can clearly be differentiated from other drug users seeking treatment. Although cannabis plays an important part in a polydrug use pattern, persons who have cannabis as their primary drug often use only this one substance. Since they regularly have brief contacts with treatment agencies, more research is needed to measure the effect of this

  15. The check your cannabis screener: a new online personalized feedback tool.

    PubMed

    Cunningham, John A; van Mierlo, Trevor

    2009-01-01

    This brief report describes the development and first year of use of an Internet-based screener for Cannabis users. Two versions of the Check Your Cannabis screener were compared, one linked to an already established harm reduction website for young Cannabis users (as an exercise called "Check how I compare with others," on www.WhatsWithWeed.ca) and the other a standalone version (www.CheckYourCannabis.net). The What's With Weed version attracted ten times more users and had a significantly younger audience as compared to the standalone version, underlining the benefits of targeting a website to a specific audience and linking to websites with already established reputations. Further work is needed to establish any impact on actual Cannabis use from taking the Check Your Cannabis screener.

  16. Cannabis and Neuropsychiatry, 2: The Longitudinal Risk of Psychosis as an Adverse Outcome.

    PubMed

    Andrade, Chittaranjan

    2016-06-01

    Psychosis is one of the most serious among the adverse effects associated with cannabis use. The association between cannabis use and psychosis has been variously explored in a series of recent meta-analyses. The results of these meta-analyses show that persons who develop psychosis experience onset of psychosis about 2-3 years earlier if they are cannabis users; this effect is not observed with alcohol or other substance use. Higher levels of cannabis use are associated with greater risk of psychosis. Current cannabis abuse or dependence (but not past use or lower levels of current use) increases the risk of transition into psychosis in persons at ultrahigh risk of psychosis. About a third of patients with first-episode psychosis are cannabis users, and, at follow-up, about half of these users are found to continue their cannabis use. Continued cannabis use (in those who are treated after developing psychosis) is associated with higher risk of relapse into psychosis, and discontinuation of cannabis use reduces the risk of relapse to that in cannabis nonusers. Finally, persons with psychosis who continue to use cannabis have more severe positive symptoms and poorer levels of functioning. Because experimental studies in humans show that cannabinoids and cannabis can induce psychotic symptoms, it is reasonable to assume that the epidemiologic data indicate a causal effect of cannabis in anticipating, triggering, or exacerbating psychosis in vulnerable individuals and in worsening the course and outcome of the illness in those who continue to use the substance. Given the public health implications of these findings, the trend to legalize medical marijuana must be viewed with concern, and efforts are necessary to educate patients and the public about the serious mental and physical health risks associated with cannabis use and abuse.

  17. Cannabis and Neuropsychiatry, 2: The Longitudinal Risk of Psychosis as an Adverse Outcome.

    PubMed

    Andrade, Chittaranjan

    2016-06-01

    Psychosis is one of the most serious among the adverse effects associated with cannabis use. The association between cannabis use and psychosis has been variously explored in a series of recent meta-analyses. The results of these meta-analyses show that persons who develop psychosis experience onset of psychosis about 2-3 years earlier if they are cannabis users; this effect is not observed with alcohol or other substance use. Higher levels of cannabis use are associated with greater risk of psychosis. Current cannabis abuse or dependence (but not past use or lower levels of current use) increases the risk of transition into psychosis in persons at ultrahigh risk of psychosis. About a third of patients with first-episode psychosis are cannabis users, and, at follow-up, about half of these users are found to continue their cannabis use. Continued cannabis use (in those who are treated after developing psychosis) is associated with higher risk of relapse into psychosis, and discontinuation of cannabis use reduces the risk of relapse to that in cannabis nonusers. Finally, persons with psychosis who continue to use cannabis have more severe positive symptoms and poorer levels of functioning. Because experimental studies in humans show that cannabinoids and cannabis can induce psychotic symptoms, it is reasonable to assume that the epidemiologic data indicate a causal effect of cannabis in anticipating, triggering, or exacerbating psychosis in vulnerable individuals and in worsening the course and outcome of the illness in those who continue to use the substance. Given the public health implications of these findings, the trend to legalize medical marijuana must be viewed with concern, and efforts are necessary to educate patients and the public about the serious mental and physical health risks associated with cannabis use and abuse. PMID:27337422

  18. Two Sides of the Same Coin: Cannabis Dependence and Mental Health Problems in Help-Seeking Adolescent and Young Adult Outpatients

    ERIC Educational Resources Information Center

    Norberg, Melissa M.; Battisti, Robert A.; Copeland, Jan; Hermens, Daniel F.; Hickie, Ian B.

    2012-01-01

    The aim of the current study was to delineate the psychiatric profile of cannabis dependent young people (14-29 years old) with mental health problems (N = 36) seeking treatment via a research study. To do so, the Structured Clinical Interview for DSM-IV-TR Axis I Disorders and the Structured Clinical Interview for DSM-IV Childhood Diagnoses were…

  19. A critique of cannabis legalization proposals in Canada.

    PubMed

    Kalant, Harold

    2016-08-01

    An editorial in this issue describes a cannabis policy framework document issued by a major Canadian research centre, calling for legalization of non-medical use under strict controls to prevent increase in use, especially by adolescents and young adults who are most vulnerable to adverse effects of cannabis. It claims that such a system would eliminate the severe personal, social and monetary costs of prohibition, diminish the illicit market, and provide more humane management of cannabis use disorders. It claims that experience with regulation of alcohol and tobacco will enable a system based on public health principles to control access of youth to cannabis without the harm caused by prohibition. The present critique argues that the claims made against decriminalization and for legalization are unsupported, or even contradicted, by solid evidence. Early experience in other jurisdictions suggests that legalization increases use by adolescents and its attendant harms. Regulation of alcohol use does not provide a good model for cannabis controls because there is widespread alcohol use and harm among adolescents and young adults. Government monopolies of alcohol sale have been used primarily as sources of revenue rather than for guarding public health, and no reason has been offered to believe they would act differently with respect to cannabis. Good policy decisions require extensive unbiased information about the individual and social benefits and costs of both drug use and proposed control measures, and value judgments about the benefit/harm balance of each option. Important parts of the necessary knowledge about cannabis are not yet available, so that the value judgments are not yet possible. Therefore, a better case can be made for eliminating some of the harms of prohibition by decriminalization of cannabis possession and deferring decision about legalization until the necessary knowledge has been acquired.

  20. A critique of cannabis legalization proposals in Canada.

    PubMed

    Kalant, Harold

    2016-08-01

    An editorial in this issue describes a cannabis policy framework document issued by a major Canadian research centre, calling for legalization of non-medical use under strict controls to prevent increase in use, especially by adolescents and young adults who are most vulnerable to adverse effects of cannabis. It claims that such a system would eliminate the severe personal, social and monetary costs of prohibition, diminish the illicit market, and provide more humane management of cannabis use disorders. It claims that experience with regulation of alcohol and tobacco will enable a system based on public health principles to control access of youth to cannabis without the harm caused by prohibition. The present critique argues that the claims made against decriminalization and for legalization are unsupported, or even contradicted, by solid evidence. Early experience in other jurisdictions suggests that legalization increases use by adolescents and its attendant harms. Regulation of alcohol use does not provide a good model for cannabis controls because there is widespread alcohol use and harm among adolescents and young adults. Government monopolies of alcohol sale have been used primarily as sources of revenue rather than for guarding public health, and no reason has been offered to believe they would act differently with respect to cannabis. Good policy decisions require extensive unbiased information about the individual and social benefits and costs of both drug use and proposed control measures, and value judgments about the benefit/harm balance of each option. Important parts of the necessary knowledge about cannabis are not yet available, so that the value judgments are not yet possible. Therefore, a better case can be made for eliminating some of the harms of prohibition by decriminalization of cannabis possession and deferring decision about legalization until the necessary knowledge has been acquired. PMID:27292414

  1. Hippocampal harms, protection and recovery following regular cannabis use.

    PubMed

    Yücel, M; Lorenzetti, V; Suo, C; Zalesky, A; Fornito, A; Takagi, M J; Lubman, D I; Solowij, N

    2016-01-12

    Shifting policies towards legalisation of cannabis for therapeutic and recreational use raise significant ethical issues for health-care providers seeking evidence-based recommendations. We investigated whether heavy cannabis use is associated with persistent harms to the hippocampus, if exposure to cannabidiol offers protection, and whether recovery occurs with abstinence. To do this, we assessed 111 participants: 74 long-term regular cannabis users (with an average of 15.4 years of use) and 37 non-user healthy controls. Cannabis users included subgroups of participants who were either exposed to Δ9-tetrahydrocannabinol (THC) but not to cannabidiol (CBD) or exposed to both, and former users with sustained abstinence. Participants underwent magnetic resonance imaging from which three measures of hippocampal integrity were assessed: (i) volume; (ii) fractional anisotropy; and (iii) N-acetylaspartate (NAA). Three curve-fitting models across the entire sample were tested for each measure to examine whether cannabis-related hippocampal harms are persistent, can be minimised (protected) by exposure to CBD or recovered through long-term abstinence. These analyses supported a protection and recovery model for hippocampal volume (P=0.003) and NAA (P=0.001). Further pairwise analyses showed that cannabis users had smaller hippocampal volumes relative to controls. Users not exposed to CBD had 11% reduced volumes and 15% lower NAA concentrations. Users exposed to CBD and former users did not differ from controls on any measure. Ongoing cannabis use is associated with harms to brain health, underpinned by chronic exposure to THC. However, such harms are minimised by CBD, and can be recovered with extended periods of abstinence.

  2. Hippocampal harms, protection and recovery following regular cannabis use

    PubMed Central

    Yücel, M; Lorenzetti, V; Suo, C; Zalesky, A; Fornito, A; Takagi, M J; Lubman, D I; Solowij, N

    2016-01-01

    Shifting policies towards legalisation of cannabis for therapeutic and recreational use raise significant ethical issues for health-care providers seeking evidence-based recommendations. We investigated whether heavy cannabis use is associated with persistent harms to the hippocampus, if exposure to cannabidiol offers protection, and whether recovery occurs with abstinence. To do this, we assessed 111 participants: 74 long-term regular cannabis users (with an average of 15.4 years of use) and 37 non-user healthy controls. Cannabis users included subgroups of participants who were either exposed to Δ9-tetrahydrocannabinol (THC) but not to cannabidiol (CBD) or exposed to both, and former users with sustained abstinence. Participants underwent magnetic resonance imaging from which three measures of hippocampal integrity were assessed: (i) volume; (ii) fractional anisotropy; and (iii) N-acetylaspartate (NAA). Three curve-fitting models across the entire sample were tested for each measure to examine whether cannabis-related hippocampal harms are persistent, can be minimised (protected) by exposure to CBD or recovered through long-term abstinence. These analyses supported a protection and recovery model for hippocampal volume (P=0.003) and NAA (P=0.001). Further pairwise analyses showed that cannabis users had smaller hippocampal volumes relative to controls. Users not exposed to CBD had 11% reduced volumes and 15% lower NAA concentrations. Users exposed to CBD and former users did not differ from controls on any measure. Ongoing cannabis use is associated with harms to brain health, underpinned by chronic exposure to THC. However, such harms are minimised by CBD, and can be recovered with extended periods of abstinence. PMID:26756903

  3. Investigating the interaction between schizotypy, divergent thinking and cannabis use

    PubMed Central

    Schafer, Gráinne; Feilding, Amanda; Morgan, Celia J.A.; Agathangelou, Maria; Freeman, Tom P.; Valerie Curran, H.

    2012-01-01

    Cannabis acutely increases schizotypy and chronic use is associated with elevated rates of psychosis. Creative individuals have higher levels of schizotypy, however links between cannabis use, schizotypy and creativity have not been investigated. We investigated the effects of cannabis smoked naturalistically on schizotypy and divergent thinking, a measure of creativity. One hundred and sixty cannabis users were tested on 1 day when sober and another day when intoxicated with cannabis. State and trait measures of both schizotypy and creativity were administered. Quartile splits compared those lowest (n = 47) and highest (n = 43) in trait creativity. Cannabis increased verbal fluency in low creatives to the same level as that of high creatives. Cannabis increased state psychosis-like symptoms in both groups and the high creativity group were significantly higher in trait schizotypy, but this does not appear to be linked to the verbal fluency change. Acute cannabis use increases divergent thinking as indexed by verbal fluency in low creatives. PMID:22230356

  4. Effect of Long-Term Cannabis Use on Axonal Fibre Connectivity

    ERIC Educational Resources Information Center

    Zalesky, Andrew; Solowij, Nadia; Yucel, Murat; Lubman, Dan I.; Takagi, Michael; Harding, Ian H.; Lorenzetti, Valentina; Wang, Ruopeng; Searle, Karissa; Pantelis, Christos; Seal, Marc

    2012-01-01

    Cannabis use typically begins during adolescence and early adulthood, a period when cannabinoid receptors are still abundant in white matter pathways across the brain. However, few studies to date have explored the impact of regular cannabis use on white matter structure, with no previous studies examining its impact on axonal connectivity. The…

  5. Tobacco use among Norwegian adolescents: from cigarettes to snus

    PubMed Central

    Pedersen, Willy; von Soest, Tilmann

    2014-01-01

    Aims To: (i) investigate the development of smoking and snus use among Norwegian adolescents, and (ii) describe the users in each group. Design Two population-based surveys with identical procedures in 2002 (response rate 91.0%) and 2010 (response rate 84.3%). Setting Norway. Participants A total of 6217 respondents, aged 16–17 years. Measurements Data were collected on smoking and snus use, socio-demographic factors, school adjustment, social network, sport activities, alcohol and cannabis use and depression symptoms. Findings Prevalence of daily smoking fell from 23.6% in 2002 to 6.8% in 2010 (P < 0.001), while the prevalence of daily snus use increased from 4.3 to 11.9% (P < 0.001). Dual daily use of cigarettes and snus remained at 1%. The relative proportion of non-daily smokers using snus increased steeply. Both snus users and smokers reported more adverse socio-economic backgrounds, less favourable school adjustment and higher levels of alcohol intoxication and cannabis use than non-users of tobacco. However, snus users were better adjusted to school and used cannabis less often than smokers. Conclusions Adolescent smoking prevalence has fallen dramatically in Norway, accompanied by a smaller increase in snus use. Young snus users in Norway have many of the same risk factors as smokers, but to a lesser degree. PMID:24521070

  6. Cannabis Smoking in 2015

    PubMed Central

    Biehl, Jason R.

    2015-01-01

    Recent legislative successes allowing expanded access to recreational and medicinal cannabis have been associated with its increased use by the public, despite continued debates regarding its safety within the medical and scientific communities. Despite legislative changes, cannabis is most commonly used by smoking, although alternatives to inhalation have also emerged. Moreover, the composition of commercially available cannabis has dramatically changed in recent years. Therefore, developing sound scientific information regarding its impact on lung health is imperative, particularly because published data conducted prior to widespread legalization are conflicting and inconclusive. In this commentary, we delineate major observations of epidemiologic investigations examining cannabis use and the potential associated development of airways disease and lung cancer to highlight gaps in pulmonary knowledge. Additionally, we review major histopathologic alterations related to smoked cannabis and define specific areas in animal models and human clinical translational investigations that could benefit from additional development. Given that cannabis has an ongoing classification as a schedule I medication, federal funding to support investigations of modern cannabis use in terms of medicinal efficacy and safety profile on lung health have been elusive. It is clear, however, that the effects of inhaled cannabis on lung health remain uncertain and given increasing use patterns, are worthy of further investigation. PMID:25996274

  7. [Outpatient cannabis withdrawal programme].

    PubMed

    David, François; Vandevivere, Thierry; Cortes-Lebon, Marie-Anne; Bernard, Véronique; Tisserand, Laurence; Danel, Thierry

    2015-01-01

    Cannabis is the most consumed illicit substance in France, and its use can lead to dependency. Lille university hospital, le Pari association, offers patients wanting to stop using cannabis a support therapy based on positive feedback led by nurses, as well as symptomatic treatment of anxiety and sleep disorders. PMID:25751912

  8. Interaction Between Functional Genetic Variation of DRD2 and Cannabis Use on Risk of Psychosis.

    PubMed

    Colizzi, Marco; Iyegbe, Conrad; Powell, John; Ursini, Gianluca; Porcelli, Annamaria; Bonvino, Aurora; Taurisano, Paolo; Romano, Raffaella; Masellis, Rita; Blasi, Giuseppe; Morgan, Craig; Aitchison, Katherine; Mondelli, Valeria; Luzi, Sonija; Kolliakou, Anna; David, Anthony; Murray, Robin M; Bertolino, Alessandro; Di Forti, Marta

    2015-09-01

    Both cannabis use and the dopamine receptor (DRD2) gene have been associated with schizophrenia, psychosis-like experiences, and cognition. However, there are no published data investigating whether genetically determined variation in DRD2 dopaminergic signaling might play a role in individual susceptibility to cannabis-associated psychosis. We genotyped (1) a case-control study of 272 patients with their first episode of psychosis and 234 controls, and also from (2) a sample of 252 healthy subjects, for functional variation in DRD2, rs1076560. Data on history of cannabis use were collected on all the studied subjects by administering the Cannabis Experience Questionnaire. In the healthy subjects' sample, we also collected data on schizotypy and cognitive performance using the Schizotypal Personality Questionnaire and the N-back working memory task. In the case-control study, we found a significant interaction between the rs1076560 DRD2 genotype and cannabis use in influencing the likelihood of a psychotic disorder. Among cannabis users, carriers of the DRD2, rs1076560, T allele showed a 3-fold increased probability to suffer a psychotic disorder compared with GG carriers (OR = 3.07; 95% confidence interval [CI]: 1.22-7.63). Among daily users, T carrying subjects showed a 5-fold increase in the odds of psychosis compared to GG carriers (OR = 4.82; 95% CI: 1.39-16.71). Among the healthy subjects, T carrying cannabis users had increased schizotypy compared with T carrying cannabis-naïve subjects, GG cannabis users, and GG cannabis-naïve subjects (all P ≤ .025). T carrying cannabis users had reduced working memory accuracy compared with the other groups (all P ≤ .008). Thus, variation of the DRD2, rs1076560, genotype may modulate the psychosis-inducing effect of cannabis use.

  9. Interaction Between Functional Genetic Variation of DRD2 and Cannabis Use on Risk of Psychosis.

    PubMed

    Colizzi, Marco; Iyegbe, Conrad; Powell, John; Ursini, Gianluca; Porcelli, Annamaria; Bonvino, Aurora; Taurisano, Paolo; Romano, Raffaella; Masellis, Rita; Blasi, Giuseppe; Morgan, Craig; Aitchison, Katherine; Mondelli, Valeria; Luzi, Sonija; Kolliakou, Anna; David, Anthony; Murray, Robin M; Bertolino, Alessandro; Di Forti, Marta

    2015-09-01

    Both cannabis use and the dopamine receptor (DRD2) gene have been associated with schizophrenia, psychosis-like experiences, and cognition. However, there are no published data investigating whether genetically determined variation in DRD2 dopaminergic signaling might play a role in individual susceptibility to cannabis-associated psychosis. We genotyped (1) a case-control study of 272 patients with their first episode of psychosis and 234 controls, and also from (2) a sample of 252 healthy subjects, for functional variation in DRD2, rs1076560. Data on history of cannabis use were collected on all the studied subjects by administering the Cannabis Experience Questionnaire. In the healthy subjects' sample, we also collected data on schizotypy and cognitive performance using the Schizotypal Personality Questionnaire and the N-back working memory task. In the case-control study, we found a significant interaction between the rs1076560 DRD2 genotype and cannabis use in influencing the likelihood of a psychotic disorder. Among cannabis users, carriers of the DRD2, rs1076560, T allele showed a 3-fold increased probability to suffer a psychotic disorder compared with GG carriers (OR = 3.07; 95% confidence interval [CI]: 1.22-7.63). Among daily users, T carrying subjects showed a 5-fold increase in the odds of psychosis compared to GG carriers (OR = 4.82; 95% CI: 1.39-16.71). Among the healthy subjects, T carrying cannabis users had increased schizotypy compared with T carrying cannabis-naïve subjects, GG cannabis users, and GG cannabis-naïve subjects (all P ≤ .025). T carrying cannabis users had reduced working memory accuracy compared with the other groups (all P ≤ .008). Thus, variation of the DRD2, rs1076560, genotype may modulate the psychosis-inducing effect of cannabis use. PMID:25829376

  10. Psychological adverse effects of cannabis smoking: a tentative classification

    PubMed Central

    Negrete, J. C.

    1973-01-01

    This paper stresses the need for an early definition and description of the “deviant” cannabis smoker in North America. Attention is called to the fact that on this continent heavy smokers have not yet been separated as “problem” users from other smokers. A comprehensive review of possible psychological adverse effects of the drug is made. The following classification is suggested: a) Severe intoxications, b) Pathological intoxications, c) Acute cannabis psychoses, d) Subacute and chronic cannabis psychoses and e) Residual conditions. PMID:4569453

  11. Cannabis: a trigger for acute myocardial infarction? A case report.

    PubMed

    Cappelli, Francesco; Lazzeri, Chiara; Gensini, Gian Franco; Valente, Serafina

    2008-07-01

    Cannabis smoking is consistently increasing in Europe and after alcohol it is the most common recreational drug in the western world. Users and lay people believe that marijuana or hashish is safe. Over the past four decades, however, it has been well established that cannabis has pathophysiological effects on the cardiovascular system. Information concerning the link between cannabis consumption and myocardial infarction is limited and existing data are controversial on this topic. In our case report, we describe a case of a young man who after smoking marijuana experienced ST elevation myocardial infarction caused by acute thrombosis of the descending artery, submitted to efficacious primary coronary angioplasty. PMID:18545075

  12. Cannabis careers revisited: applying Howard S. Becker's theory to present-day cannabis use.

    PubMed

    Järvinen, Margaretha; Ravn, Signe

    2014-01-01

    A considerable part of today's sociological research on recreational drug use is (explicitly or implicitly) inspired by Howard Becker's classical model of deviant careers. The aim of the present paper is to directly apply Becker's theory to empirical data on present-day cannabis use and to suggest a revision of the theory. As part of this, we propose a stretch of the sociological approach represented by Becker and followers in order to include, not only recreational drug use, but also use for which young people have sought treatment. The paper is based on 30 qualitative interviews with young people in treatment for cannabis problems in Copenhagen, Denmark. We suggest a revision of Becker's career model in relation to four aspects: initiation of cannabis use, differentiation between socially integrated and individualised, disintegrated use, social control from non-users, and the users' moral stance on cannabis. A central point of the paper is that social interaction may both motivate cannabis use, as Becker proposed, and serve as a protective factor against extensive, problematic use.

  13. Influence of Handrim Wheelchair Propulsion Training in Adolescent Wheelchair Users, A Pilot Study

    PubMed Central

    Dysterheft, Jennifer L.; Rice, Ian M.; Rice, Laura A.

    2015-01-01

    Ten full-time adolescent wheelchair users (ages 13–18) completed a total of three propulsion trials on carpet and tile surfaces, at a self-selected velocity, and on a concrete surface, at a controlled velocity. All trials were performed in their personal wheelchair with force and moment sensing wheels attached bilaterally. The first two trials on each surface were used as pre-intervention control trials. The third trial was performed after receiving training on proper propulsion technique. Peak resultant force, contact angle, stroke frequency, and velocity were recorded during all trials for primary analysis. Carpet and tile trials resulted in significant increases in contact angle and peak total force with decreased stroke frequency after training. During the velocity controlled trials on concrete, significant increases in contact angle occurred, as well as decreases in stroke frequency after training. Overall, the use of a training video and verbal feedback may help to improve short-term propulsion technique in adolescent wheelchair users and decrease the risk of developing upper limb pain and injury. PMID:26042217

  14. Influence of handrim wheelchair propulsion training in adolescent wheelchair users, a pilot study.

    PubMed

    Dysterheft, Jennifer L; Rice, Ian M; Rice, Laura A

    2015-01-01

    Ten full-time adolescent wheelchair users (ages 13-18) completed a total of three propulsion trials on carpet and tile surfaces, at a self-selected velocity, and on a concrete surface, at a controlled velocity. All trials were performed in their personal wheelchair with force and moment sensing wheels attached bilaterally. The first two trials on each surface were used as pre-intervention control trials. The third trial was performed after receiving training on proper propulsion technique. Peak resultant force, contact angle, stroke frequency, and velocity were recorded during all trials for primary analysis. Carpet and tile trials resulted in significant increases in contact angle and peak total force with decreased stroke frequency after training. During the velocity controlled trials on concrete, significant increases in contact angle occurred, as well as decreases in stroke frequency after training. Overall, the use of a training video and verbal feedback may help to improve short-term propulsion technique in adolescent wheelchair users and decrease the risk of developing upper limb pain and injury.

  15. Cannabis use for chronic non-cancer pain: results of a prospective survey.

    PubMed

    Ware, Mark A; Doyle, Crystal R; Woods, Ryan; Lynch, Mary E; Clark, Alexander J

    2003-03-01

    There has been a surge in interest in medicinal cannabis in Canada. We conducted a questionnaire survey to determine the current prevalence of medicinal cannabis use among patients with chronic non-cancer pain, to estimate the dose size and frequency of cannabis use, and to describe the main symptoms for which relief was being sought. Over a 6-week period in mid-2001, 209 chronic non-cancer pain patients were recruited in an anonymous cross-sectional survey. Seventy-two (35%) subjects reported ever having used cannabis. Thirty-two (15%) subjects reported having used cannabis for pain relief (pain users), and 20 (10%) subjects were currently using cannabis for pain relief. Thirty-eight subjects denied using cannabis for pain relief (recreational users). Compared to never users, pain users were significantly younger (P=0.001) and were more likely to be tobacco users (P=0.0001). The largest group of patients using cannabis had pain caused by trauma and/or surgery (51%), and the site of pain was predominantly neck/upper body and myofascial (68% and 65%, respectively). The median duration of pain was similar in both pain users and recreational users (8 vs. 7 years; P=0.7). There was a wide range of amounts and frequency of cannabis use. Of the 32 subjects who used cannabis for pain, 17 (53%) used four puffs or less at each dosing interval, eight (25%) smoked a whole cannabis cigarette (joint) and four (12%) smoked more than one joint. Seven (22%) of these subjects used cannabis more than once daily, five (16%) used it daily, eight (25%) used it weekly and nine (28%) used it rarely. Pain, sleep and mood were most frequently reported as improving with cannabis use, and 'high' and dry mouth were the most commonly reported side effects. We conclude that cannabis use is prevalent among the chronic non-cancer pain population, for a wide range of symptoms, with considerable variability in the amounts used. Discussions between patients and health care providers concerning

  16. Emotional processing deficits in chronic cannabis use: a replication and extension.

    PubMed

    Hindocha, Chandni; Wollenberg, Olivia; Carter Leno, Virginia; Alvarez, Beatriz O; Curran, H Valerie; Freeman, Tom P

    2014-05-01

    Heavy cannabis use is associated with interpersonal problems that may arise in part from the inaccurate perception of emotional faces. Only one study reports impairments in emotional facial affect processing in heavy cannabis users; however, it is not clear whether these findings were attributable to differences between cannabis users and controls in schizotypy or gender, rather than from cannabis use itself. A total of 25 frequent cannabis users and 34 non-using controls completed an emotional processing task in an independent groups design. We asked participants to identify the emotions on faces morphed from neutral to 100% intensity, for six basic emotions. We measured percentage hit rate, sensitivity and response bias. Schizotypy was indexed using the Schizotypal Personality Questionnaire. Cannabis users showed lower accuracy and sensitivity on the emotional recognition task. Gender and schizotypy did not differ between the two groups. Men showed lower accuracy on the emotional processing task, but impairments in cannabis users remained when covarying for gender. Schizotypy negatively correlated with sensitivity scores, but this was unreliable when accounting for the groups. Chronic cannabis users showed generalised impairment in emotional processing. These results appeared as independent of the emotional processing deficits amongst men, and were not related to schizotypy.

  17. Association between schizotypal and borderline personality disorder traits, and cannabis use in young adults.

    PubMed

    Raynal, Patrick; Chabrol, Henri

    2016-09-01

    The aim of the study was to examine the association of schizotypal and borderline personality traits to cannabis use. Participants were 476 college students (95 males; 381 females; mean age of males=21; mean age of females=20.7) who completed self-report questionnaires assessing cannabis use, schizotypal and borderline personality traits. Problematic cannabis use, depressive symptoms, borderline and schizotypal traits were significantly inter-correlated. A logistic regression analysis showed that only borderline traits contributed significantly to cannabis use in the total sample. A multiple regression analysis showed that only schizotypal traits were positively and uniquely associated to problematic cannabis use symptoms among users. These results may imply that schizotypal traits are not a risk factor for initiating use, but may facilitate the development of problematic use symptoms among users. This study showed the necessity of taking into account schizotypal traits when exploring the relationships between depressive symptoms, borderline traits and cannabis use. PMID:27149691

  18. Association between schizotypal and borderline personality disorder traits, and cannabis use in young adults.

    PubMed

    Raynal, Patrick; Chabrol, Henri

    2016-09-01

    The aim of the study was to examine the association of schizotypal and borderline personality traits to cannabis use. Participants were 476 college students (95 males; 381 females; mean age of males=21; mean age of females=20.7) who completed self-report questionnaires assessing cannabis use, schizotypal and borderline personality traits. Problematic cannabis use, depressive symptoms, borderline and schizotypal traits were significantly inter-correlated. A logistic regression analysis showed that only borderline traits contributed significantly to cannabis use in the total sample. A multiple regression analysis showed that only schizotypal traits were positively and uniquely associated to problematic cannabis use symptoms among users. These results may imply that schizotypal traits are not a risk factor for initiating use, but may facilitate the development of problematic use symptoms among users. This study showed the necessity of taking into account schizotypal traits when exploring the relationships between depressive symptoms, borderline traits and cannabis use.

  19. Acute and long-term effects of cannabis use: a review.

    PubMed

    Karila, Laurent; Roux, Perrine; Rolland, Benjamin; Benyamina, Amine; Reynaud, Michel; Aubin, Henri-Jean; Lançon, Christophe

    2014-01-01

    Cannabis remains the most commonly used and trafficked illicit drug in the world. Its use is largely concentrated among young people (15- to 34-year-olds). There is a variety of cannabis use patterns, ranging from experimental use to dependent use. Men are more likely than women to report both early initiation and frequent use of cannabis. Due to the high prevalence of cannabis use, the impact of cannabis on public health may be significant. A range of acute and chronic health problems associated with cannabis use has been identified. Cannabis can frequently have negative effects in its users, which may be amplified by certain demographic and/or psychosocial factors. Acute adverse effects include hyperemesis syndrome, impaired coordination and performance, anxiety, suicidal ideations/tendencies, and psychotic symptoms. Acute cannabis consumption is also associated with an increased risk of motor vehicle crashes, especially fatal collisions. Evidence indicates that frequent and prolonged use of cannabis can be detrimental to both mental and physical health. Chronic effects of cannabis use include mood disorders, exacerbation of psychotic disorders in vulnerable people, cannabis use disorders, withdrawal syndrome, neurocognitive impairments, cardiovascular and respiratory and other diseases.

  20. Treatment of cannabis use among people with psychotic disorders: a critical review of randomised controlled trials.

    PubMed

    Baker, Amanda L; Thornton, Louise K; Hides, Leanne; Dunlop, Adrian

    2012-01-01

    There is growing and converging evidence that cannabis may be a major risk factor in people with psychotic disorders and prodromal psychotic symptoms. The lack of available pharmacological treatments for cannabis use indicates that psychological interventions should be a high priority, especially among people with psychotic disorders. However, there have been few randomised controlled trials (RCTs) of psychological interventions among this group. In the present study we critically overview RCTs of psychological and pharmacologic interventions among people with psychotic disorders, giving particular attention to those studies which report cannabis use outcomes. We then review data regarding treatment preferences among this group. RCTs of interventions within "real world" mental health systems among adults with severe mental disorders suggest that cannabis use is amenable to treatment in real world settings among people with psychotic disorders. RCTs of manual guided interventions among cannabis users indicate that while brief interventions are associated with reductions in cannabis use, longer interventions may be more effective. Additionally, RCTs reviewed suggest treatment with antipsychotic medication is not associated with a worsening of cannabis cravings or use and may be beneficial. The development of cannabinoid agonist medication may be an effective strategy for cannabis dependence and suitable for people with psychotic disorders. The development of cannabis use interventions for people with psychotic disorders should also consider patients' treatment preferences. Initial results indicate face-to-face interventions focussed on cannabis use may be preferred. Further research investigating the treatment preferences of people with psychotic disorders using cannabis is needed.

  1. Cannabidiol attenuates the appetitive effects of Delta 9-tetrahydrocannabinol in humans smoking their chosen cannabis.

    PubMed

    Morgan, Celia J A; Freeman, Tom P; Schafer, Gráinne L; Curran, H Valerie

    2010-08-01

    Worldwide cannabis dependence is increasing, as is the concentration of Delta(9)-tetrahydrocannabinol (THC) in street cannabis. At the same time, the concentration of the second most abundant cannabinoid in street cannabis, cannabidiol (CBD), is decreasing. These two cannabinoids have opposing effects both pharmacologically and behaviorally when administered in the laboratory. No research has yet examined how the ratio of these constituents impacts on the appetitive/reinforcing effects of cannabis in humans. A total of 94 cannabis users were tested 7 days apart, once while non-intoxicated and once while acutely under the influence of their own chosen smoked cannabis on dependence-related measures. Using an unprecedented methodology, a sample of cannabis (as well as saliva) was collected from each user and analyzed for levels of cannabinoids. On the basis of CBD : THC ratios in the cannabis, individuals from the top and bottom tertiles were directly compared on indices of the reinforcing effects of drugs, explicit liking, and implicit attentional bias to drug stimuli. When intoxicated, smokers of high CBD : THC strains showed reduced attentional bias to drug and food stimuli compared with smokers of low CBD : THC. Those smoking higher CBD : THC strains also showed lower self-rated liking of cannabis stimuli on both test days. Our findings suggest that CBD has potential as a treatment for cannabis dependence. The acute modulation of the incentive salience of drug cues by CBD may possibly generalize to a treatment for other addictive disorders.

  2. Dose-response effect between cannabis use and psychosis liability in a non-clinical population: evidence from a snowball sample.

    PubMed

    Ruiz-Veguilla, Miguel; Barrigón, María Luisa; Hernández, Laureano; Rubio, José Luis; Gurpegui, Manuel; Sarramea, Fernando; Cervilla, Jorge; Gutiérrez, Blanca; James, Anthony; Ferrin, Maite

    2013-08-01

    This study aimed to explore the associations between daily cannabis use and the specific profiles of subclinical symptoms in a non-clinical population obtained through snowball sampling, taking into account alcohol use, other drug use, social exclusion and age at onset of cannabis use. We included 85 daily cannabis users and 100 non-daily cannabis users. Both the case and the control populations were identified by snowball sampling. Daily cannabis use was associated with more alcohol intake and other drug use, as well as with early onset in the use of cannabis. Daily cannabis use appeared to exert a dose-response effect on first-rank symptoms, mania symptoms and auditory hallucinations, even after adjusting for sex, age, other drug use, social exclusion and age at onset of cannabis use. The paranoid dimension was only associated with the heaviest consumption of cannabis. Initial age of cannabis use modified the effects of daily cannabis use on the first-rank and voices experiences. Daily cannabis use was associated with significantly more first-rank and voices experiences among those subjects who started to use cannabis before 17 years of age. Our study supports the association of psychotic experiences with cannabis use even among non-psychotic subjects. PMID:23684550

  3. Dose-response effect between cannabis use and psychosis liability in a non-clinical population: evidence from a snowball sample.

    PubMed

    Ruiz-Veguilla, Miguel; Barrigón, María Luisa; Hernández, Laureano; Rubio, José Luis; Gurpegui, Manuel; Sarramea, Fernando; Cervilla, Jorge; Gutiérrez, Blanca; James, Anthony; Ferrin, Maite

    2013-08-01

    This study aimed to explore the associations between daily cannabis use and the specific profiles of subclinical symptoms in a non-clinical population obtained through snowball sampling, taking into account alcohol use, other drug use, social exclusion and age at onset of cannabis use. We included 85 daily cannabis users and 100 non-daily cannabis users. Both the case and the control populations were identified by snowball sampling. Daily cannabis use was associated with more alcohol intake and other drug use, as well as with early onset in the use of cannabis. Daily cannabis use appeared to exert a dose-response effect on first-rank symptoms, mania symptoms and auditory hallucinations, even after adjusting for sex, age, other drug use, social exclusion and age at onset of cannabis use. The paranoid dimension was only associated with the heaviest consumption of cannabis. Initial age of cannabis use modified the effects of daily cannabis use on the first-rank and voices experiences. Daily cannabis use was associated with significantly more first-rank and voices experiences among those subjects who started to use cannabis before 17 years of age. Our study supports the association of psychotic experiences with cannabis use even among non-psychotic subjects.

  4. Is the medical use of cannabis a therapeutic option for children?

    PubMed

    Rieder, Michael J

    2016-01-01

    Cannabis is a psychoactive compound with a long history of recreational and therapeutic use. Current considerations regarding cannabis use for medical purposes in children have been stimulated by recent case reports describing its beneficial effect with refractory epilepsy. Overall, there are insufficient data to support either the efficacy or safety of cannabis use for any indications in children, and an increasing body of data suggests possible harm, most importantly in specific conditions. The potential for cannabis as a therapeutic agent must be evaluated carefully for both efficacy and safety in treating specific paediatric health conditions. Smoking is not an acceptable mode of drug delivery for children. The use of cannabis for medical purposes in specific cases should not be construed as a justification for recreational cannabis use by adolescents. Recommendations for therapeutic use in exceptional paediatric cases are offered, always providing that this treatment course is carefully evaluated in individuals and in ongoing, well-designed research studies to determine safety and efficacy.

  5. Cannabinoid replacement therapy (CRT): Nabiximols (Sativex) as a novel treatment for cannabis withdrawal.

    PubMed

    Allsop, D J; Lintzeris, N; Copeland, J; Dunlop, A; McGregor, I S

    2015-06-01

    Cannabis is a common recreational drug that is generally considered to have low addictive potential. However, an increasing number of cannabis users are seeking treatment for dependence on the drug. There is interest in using agonist (substitution) pharmacotherapies to treat cannabis dependence and here we outline a novel approach involving a buccal spray (nabiximols) that contains tetrahydrocannabinol (THC) and cannabidiol (CBD). We review recent research with nabiximols and highlight findings relevant to clinical practice. PMID:25777582

  6. Can cannabis cause psychosis?

    PubMed

    Michaels, Timothy I; Novakovic, Vladan

    2015-01-01

    In recent years, increasing popular support for the medicinal and recreational use of cannabis has led to legalization for both medicinal and recreational purposes in the United States. To the extent that these changes in policy lead to increase widespread use, it is important to consider the association between heavy chronic cannabis use and the onset of psychotic illnesses, such as schizophrenia. This article provides a brief review of evidence that support cannabis use as a risk factor in the complex etiology of psychotic illness. In addition to reviewing psychopharmacology, longitudinal research, and clinical studies, the article addresses the potential implications of current research on public health policy. PMID:25768856

  7. Cannabis induced asystole.

    PubMed

    Brancheau, Daniel; Blanco, Jessica; Gholkar, Gunjan; Patel, Brijesh; Machado, Christian

    2016-01-01

    Cannabis or marijuana is the most used recreational, and until recently illegal, drug in the United States. Although cannabis has medicinal use, its consumption has been linked to motor vehicle accidents in dose dependent fashion. Marijuana and other cannabinoids produce a multitude of effects on the human body that may result in these motor vehicle accidents. Some of the effects that marijuana has been known to cause include altered sensorium, diminished reflexes, and increased vagal tone. We present a case of cannabis induced asystole from hypervagotonia. PMID:26520167

  8. Position statement on cannabis.

    PubMed

    Stein For The Executive Committee Of The Central Drug Authority, Dan Joseph

    2016-05-16

    There is an ongoing national debate around cannabis policy. This brief position statement by the Executive Committee of the Central Drug Authorityoutlines some of the factors that have contributed to this debate, delineates reduction strategies, summarises the harms and benefits ofmarijuana, and provides recommendations. These recommendations emphasise an integrated and evidence-based approach, the need forresources to implement harm reduction strategies against continued and chronic use of alcohol and cannabis, and the potential value of afocus on decriminalisation rather than the legalisation of cannabis.

  9. Cannabis induced asystole.

    PubMed

    Brancheau, Daniel; Blanco, Jessica; Gholkar, Gunjan; Patel, Brijesh; Machado, Christian

    2016-01-01

    Cannabis or marijuana is the most used recreational, and until recently illegal, drug in the United States. Although cannabis has medicinal use, its consumption has been linked to motor vehicle accidents in dose dependent fashion. Marijuana and other cannabinoids produce a multitude of effects on the human body that may result in these motor vehicle accidents. Some of the effects that marijuana has been known to cause include altered sensorium, diminished reflexes, and increased vagal tone. We present a case of cannabis induced asystole from hypervagotonia.

  10. [Cannabis in France, new insights].

    PubMed

    Costentin, Jean

    2014-03-01

    France holds the record for cannabis use in Europe, especially among adolescents. This drug of abuse is thus mainly used during a very sensitive period of brain development, education, vehicle driving and development of life projects. In addition, synthetic derivatives of tetrahydrocannabinol (THC), which are more noxious than cannabis itself are now appearing on the market. Traficking and cultivation for personnal use have intensified; products proposed for sale are richer in THC; and some methods of consumption (e-cigarettes, vaporizers, water pipes) increase the supply of THC to the lungs and thence to the body and brain. It is in this context that attempts are being made to legalize this drug of abuse. Other attempts are made to disguise it as a medication. Meanwhile, the list of its psychic as well as physical damages grows longer, with some very severe cases of major injuries. This evolution takes place in spite of numerous warnings expressed by the French Academy of Medicine. Subsequently, it is prompted to carefully and vigorously denounce these events. This will be the aim of this thematic session. PMID:26427294

  11. [Cannabis in France, new insights].

    PubMed

    Costentin, Jean

    2014-03-01

    France holds the record for cannabis use in Europe, especially among adolescents. This drug of abuse is thus mainly used during a very sensitive period of brain development, education, vehicle driving and development of life projects. In addition, synthetic derivatives of tetrahydrocannabinol (THC), which are more noxious than cannabis itself are now appearing on the market. Traficking and cultivation for personnal use have intensified; products proposed for sale are richer in THC; and some methods of consumption (e-cigarettes, vaporizers, water pipes) increase the supply of THC to the lungs and thence to the body and brain. It is in this context that attempts are being made to legalize this drug of abuse. Other attempts are made to disguise it as a medication. Meanwhile, the list of its psychic as well as physical damages grows longer, with some very severe cases of major injuries. This evolution takes place in spite of numerous warnings expressed by the French Academy of Medicine. Subsequently, it is prompted to carefully and vigorously denounce these events. This will be the aim of this thematic session.

  12. Correlates of Intentions to Use Cannabis among US High School Seniors in the Case of Cannabis Legalization

    PubMed Central

    Palamar, Joseph J.; Ompad, Danielle C.; Petkova, Eva

    2014-01-01

    Background Support for cannabis (“marijuana”) legalization is increasing in the United States (US). Use was recently legalized in two states and in Uruguay, and other states and countries are expected to follow suit. This study examined intentions to use among US high school seniors if cannabis were to become legally available. Methods Data from the last five cohorts (2007–2011) of high school seniors in Monitoring the Future, an annual nationally representative survey of students in the US were utilized. Data were analyzed separately for the 6,116 seniors who reported no lifetime use of cannabis and the 3,828 seniors who reported lifetime use (weighted Ns). We examined whether demographic characteristics, substance use and perceived friend disapproval towards cannabis use were associated with 1) intention to try cannabis among non-lifetime users, and 2) intention to use cannabis as often or more often among lifetime users, if cannabis was legal to use. Results Ten percent of non-cannabis-using students reported intent to initiate use if legal and this would constitute a 5.6% absolute increase in lifetime prevalence of cannabis use in this age group from 45.6% (95% CI=46.6, 44.6) to 51.2% (95% CI=50.2, 52.2). Eighteen percent of lifetime users reported intent to use cannabis more often if it was legal. Odds for intention to use outcomes increased among groups already at high risk for use (e.g., males, whites, cigarette smokers) and odds were reduced when friends disapproved of use. However, large proportions of subgroups of students normally at low risk for use (e.g., non-cigarette-smokers, religious students, those with friends who disapprove of use) reported intention to use if legal. Recent use was also a risk factor for reporting intention to use as often or more often. Conclusion Prevalence of cannabis use is expected to increase if cannabis is legal to use and legally available. PMID:24589410

  13. Cannabis Use in Patients with Fibromyalgia: Effect on Symptoms Relief and Health-Related Quality of Life

    PubMed Central

    Fiz, Jimena; Durán, Marta; Capellà, Dolors; Carbonell, Jordi; Farré, Magí

    2011-01-01

    Background The aim of this study was to describe the patterns of cannabis use and the associated benefits reported by patients with fibromyalgia (FM) who were consumers of this drug. In addition, the quality of life of FM patients who consumed cannabis was compared with FM subjects who were not cannabis users. Methods Information on medicinal cannabis use was recorded on a specific questionnaire as well as perceived benefits of cannabis on a range of symptoms using standard 100-mm visual analogue scales (VAS). Cannabis users and non-users completed the Fibromyalgia Impact Questionnaire (FIQ), the Pittsburgh Sleep Quality Index (PSQI) and the Short Form 36 Health Survey (SF-36). Results Twenty-eight FM patients who were cannabis users and 28 non-users were included in the study. Demographics and clinical variables were similar in both groups. Cannabis users referred different duration of drug consumption; the route of administration was smoking (54%), oral (46%) and combined (43%). The amount and frequency of cannabis use were also different among patients. After 2 hours of cannabis use, VAS scores showed a statistically significant (p<0.001) reduction of pain and stiffness, enhancement of relaxation, and an increase in somnolence and feeling of well being. The mental health component summary score of the SF-36 was significantly higher (p<0.05) in cannabis users than in non-users. No significant differences were found in the other SF-36 domains, in the FIQ and the PSQI. Conclusions The use of cannabis was associated with beneficial effects on some FM symptoms. Further studies on the usefulness of cannabinoids in FM patients as well as cannabinoid system involvement in the pathophysiology of this condition are warranted. PMID:21533029

  14. The association between psychopathology and substance use: adolescent and young adult substance users in inpatient treatment in Cape Town, South Africa

    PubMed Central

    Saban, Amina; Flisher, Alan; Laubscher, Ria; London, Leslie; Morojele, Neo

    2014-01-01

    Introduction Evidence suggests that comorbid psychopathology can negatively affect treatment outcomes in substance users. In South Africa, limited information exists regarding the prevalence, nature and role of psychiatric comorbidity in substance users. This study examined psychiatric comorbidity and its association with specific substance use, and young adult substance users in treatment for substance use. Methods Male and female inpatient substance users (n=95; ages 17-30 years) were sampled consecutively in order of admission from three clinics in Cape Town. An interview schedule was administered to elicit patients’ sociodemographic and substance use history details. The computer-assisted Diagnostic Interview Schedule DSM IV (C-DIS IV) was administered to screen patients for current psychiatric disorders. Resuls The sample was largely male, Coloured, Muslim and single. Cannabis (51.6%) and crystal methamphetamine (17.9%) were the most common first substances of use. Heroin (53.7%) and crystal methamphetamine (33.7%) were the most common substances for which treatment was sought (primary substances). The most common comorbid psychopathologies were anti-social personality disorder (ASPD 87.4%) and conduct disorder (CD 67.4%). Regression analyses showed a marginally significant association between specific phobia and first use of cannabis, but indicated no statistically significant associations between psychopathology and substance use. Conclusion The results demonstrated a high proportion of previously unidentified comorbid psychopathology in inpatient substance users. Further research is needed to investigate psychiatric comorbidity in inpatient substance users. PMID:24643118

  15. Adverse effects of cannabis on health: an update of the literature since 1996.

    PubMed

    Kalant, Harold

    2004-08-01

    Recent research has clarified a number of important questions concerning adverse effects of cannabis on health. A causal role of acute cannabis intoxication in motor vehicle and other accidents has now been shown by the presence of measurable levels of Delta(9)-tetrahydrocannabinol (THC) in the blood of injured drivers in the absence of alcohol or other drugs, by surveys of driving under the influence of cannabis, and by significantly higher accident culpability risk of drivers using cannabis. Chronic inflammatory and precancerous changes in the airways have been demonstrated in cannabis smokers, and the most recent case-control study shows an increased risk of airways cancer that is proportional to the amount of cannabis use. Several different studies indicate that the epidemiological link between cannabis use and schizophrenia probably represents a causal role of cannabis in precipitating the onset or relapse of schizophrenia. A weaker but significant link between cannabis and depression has been found in various cohort studies, but the nature of the link is not yet clear. A large body of evidence now demonstrates that cannabis dependence, both behavioral and physical, does occur in about 7-10% of regular users, and that early onset of use, and especially of weekly or daily use, is a strong predictor of future dependence. Cognitive impairments of various types are readily demonstrable during acute cannabis intoxication, but there is no suitable evidence yet available to permit a decision as to whether long-lasting or permanent functional losses can result from chronic heavy use in adults. However, a small but growing body of evidence indicates subtle but apparently permanent effects on memory, information processing, and executive functions, in the offspring of women who used cannabis during pregnancy. In total, the evidence indicates that regular heavy use of cannabis carries significant risks for the individual user and for the health care system.

  16. Cannabis Withdrawal in Patients With and Without Opioid Dependence

    PubMed Central

    Chauchard, Emeline; Goncharov, Oleg; Krupitsky, Evgeny; Gorelick, David A.

    2014-01-01

    Background Cannabis use is common among opioid-dependent individuals, but little is known about cannabis withdrawal in this population. Method Thirty inpatients (57% men) completed the Marijuana Quit Questionnaire (MJQQ) after completing acute heroin detoxification treatment in St. Petersburg, Russia. The MJQQ collected data on motivations for quitting, withdrawal symptoms, and coping strategies used to help maintain abstinence during their most “userious” (self-defined) quit attempt made without formal treatment outside a controlled environment. Results At the start of their quit attempt, 70% of participants smoked cannabis at least weekly (40% daily), averaging [SD] 2.73 [1.95] joints daily; 60% were heroin-dependent. Subjects with heroin dependence were significantly older at the start of their quit attempt (22.9 [3.6] years vs. 19.1 [2.9] years), were significantly less likely to report withdrawal irritability/anger/aggression (22% vs. 58%), restlessness (0% vs. 25%), or physical symptoms (6% vs. 33%), or to meet diagnostic criteria for DSM-5 cannabis withdrawal syndrome (6% vs. 33%), and had shorter duration of abstinence (29.6 [28.7] months vs. 73.7 [44.1] months) than those without heroin dependence. Conclusion Cannabis users with opioid dependence are less likely to experience cannabis withdrawal, suggesting that opiate use may prevent or mask the experience of cannabis withdrawal. Results should be considered preliminary due to small convenience sample and retrospective data. PMID:24745656

  17. Drinking, cannabis use and driving among Ontario students.

    PubMed

    Adlaf, Edward M; Mann, Robert E; Paglia, Angela

    2003-03-01

    Little is known about the risk of injury among adolescents who drive after the use of alcohol or cannabis or ride in cars driven by drunk drivers. We examined data from self-administered interviews with 1846 students in grades 7 to 13 who participated in the 2001 Ontario Student Drug Use Survey about their experiences related to alcohol, cannabis and driving during the 12 months preceding the survey. In all, 31.9% of the students reported being a passenger in a car driven by a drunk driver; of the students in grades 10 to 13 who had a driver's licence, 15.1% reported driving within an hour after consuming 2 or more drinks, and 19.7% reported driving within an hour after using cannabis. Our study shows that a sizeable proportion of adolescents are exposed to alcohol- and drug-related driving risks.

  18. Prevalence of internet addiction and its association with stressful life events and psychological symptoms among adolescent internet users.

    PubMed

    Tang, Jie; Yu, Yizhen; Du, Yukai; Ma, Ying; Zhang, Dongying; Wang, Jiaji

    2014-03-01

    Internet addiction (IA) among adolescents is a serious public health problem around the world. However, there have been few studies that examine the association between IA and stressful life events and psychological symptoms among Chinese adolescent internet users. We examined the association between IA and stressful life events and psychological symptoms among a random sample of school students who were internet users (N=755) in Wuhan, China. Internet addiction, stressful life events, coping style and psychological symptoms were measured by self-rated scales. The prevalence rate of internet addiction was 6.0% among adolescent internet users. Logistic regression analyses indicated that stressors from interpersonal problem and school related problem and anxiety symptoms were significantly associated with IA after controlling for demographic characteristics. Analyses examining the coping style with the IA revealed that negative coping style may mediate the effects of stressful life events to increase the risk of IA. However, no significant interaction of stressful life events and psychological symptoms was found. These findings of the current study indicate a high prevalence of internet addiction among Chinese adolescent internet users and highlight the importance of stressors from interpersonal problem and school related problem as a risk factor for IA which mainly mediated through negative coping style.

  19. Relation between cannabis use and subcortical volumes in people at clinical high risk of psychosis.

    PubMed

    Buchy, Lisa; Mathalon, Daniel H; Cannon, Tyrone D; Cadenhead, Kristin S; Cornblatt, Barbara A; McGlashan, Thomas H; Perkins, Diana O; Seidman, Larry J; Tsuang, Ming T; Walker, Elaine F; Woods, Scott W; Bearden, Carrie E; Addington, Jean

    2016-08-30

    Among people at genetic risk of schizophrenia, those who use cannabis show smaller thalamic and hippocampal volumes. We evaluated this relationship in people at clinical high risk (CHR) of psychosis. The Alcohol and Drug Use Scale was used to identify 132 CHR cannabis users, the majority of whom were non-dependent cannabis users, 387 CHR non-users, and 204 healthy control non-users, and all participants completed magnetic resonance imaging scans. Volumes of the thalamus, hippocampus and amygdala were extracted with FreeSurfer, and compared across groups. Comparing all CHR participants with healthy control participants revealed no significant differences in volumes of any ROI. However, when comparing CHR users to CHR non-users, a significant ROI×Cannabis group effect emerged: CHR users showed significantly smaller amygdala compared to CHR non-users. However, when limiting analysis to CHR subjects who reported using alcohol at a 'use without impairment' severity level, the amygdala effect was non-significant; rather, smaller hippocampal volumes were seen in CHR cannabis users compared to non-users. Controlling statistically for effects of alcohol and tobacco use rendered all results non-significant. These results highlight the importance of controlling for residual confounding effects of other substance use when examining the relationship between cannabis use and neural structure. PMID:27289213

  20. Cross-national differences in clinically significant cannabis problems: epidemiologic evidence from 'cannabis-only' smokers in the United States, Mexico, and Colombia

    PubMed Central

    2010-01-01

    Background Epidemiological studies show wide variability in the occurrence of cannabis smoking and related disorders across countries. This study aims to estimate cross-national variation in cannabis users' experience of clinically significant cannabis-related problems in three countries of the Americas, with a focus on cannabis users who may have tried alcohol or tobacco, but who have not used cocaine, heroin, LSD, or other internationally regulated drugs. Methods Data are from the World Mental Health Surveys Initiative and the National Latino and Asian American Study, with probability samples in Mexico (n = 4426), Colombia (n = 5,782) and the United States (USA; n = 8,228). The samples included 212 'cannabis only' users in Mexico, 260 in Colombia and 1,724 in the USA. Conditional GLM with GEE and 'exact' methods were used to estimate variation in the occurrence of clinically significant problems in cannabis only (CO) users across these surveyed populations. Results The experience of cannabis-related problems was quite infrequent among CO users in these countries, with weighted frequencies ranging from 1% to 5% across survey populations, and with no appreciable cross-national variation in general. CO users in Colombia proved to be an exception. As compared to CO users in the USA, the Colombia smokers were more likely to have experienced cannabis-associated 'social problems' (odds ratio, OR = 3.0; 95% CI = 1.4, 6.3; p = 0.004) and 'legal problems' (OR = 9.7; 95% CI = 2.7, 35.2; p = 0.001). Conclusions This study's most remarkable finding may be the similarity in occurrence of cannabis-related problems in this cross-national comparison within the Americas. Wide cross-national variations in estimated population-level cumulative incidence of cannabis use disorders may be traced to large differences in cannabis smoking prevalence, rather than qualitative differences in cannabis experiences. More research is needed to identify conditions that might make cannabis

  1. Screening Medications for the Treatment of Cannabis Use Disorder.

    PubMed

    Panlilio, L V; Justinova, Z; Trigo, J M; Le Foll, B

    2016-01-01

    Cannabis use has been increasingly accepted legally and in public opinion. However, cannabis has the potential to produce adverse physical and mental health effects, and cannabis use disorder (CUD) occurs in a substantial percentage of both occasional and daily cannabis users. Many people have difficulty discontinuing use despite receiving treatment. Therefore, it would be beneficial to develop safe and effective medications for treating CUD. To achieve this, methods have been developed for screening and evaluating potential medications using animal models and controlled experimental protocols in human volunteers. In this chapter, we describe: (1) animal models available for assessing the effect of potential medications on specific aspects of CUD, (2) the main findings obtained so far with these animal models, (3) the approaches used to assess potential medications in humans in laboratory experiments and clinical trials, and (4) the effectiveness of several potential pharmacotherapies on particular aspects of CUD modeled in these human studies.

  2. Cannabis, Cigarettes, and Their Co-Occurring Use: Disentangling Differences in Gray Matter Volume

    PubMed Central

    Jagannathan, Kanchana; Hager, Nathan; Childress, Anna Rose; Rao, Hengyi; Franklin, Teresa R.

    2015-01-01

    Background: Structural magnetic resonance imaging techniques are powerful tools for examining the effects of drug use on the brain. The nicotine and cannabis literature has demonstrated differences between nicotine cigarette smokers and cannabis users compared to controls in brain structure; however, less is known about the effects of co-occurring cannabis and tobacco use. Methods: We used voxel-based morphometry to examine gray matter volume differences between four groups: (1) cannabis-dependent individuals who do not smoke tobacco (Cs); (2) cannabis-dependent individuals who smoke tobacco (CTs); (3) cannabis-naïve, nicotine-dependent individuals who smoke tobacco (Ts); and (4) healthy controls (HCs). We also explored associations between gray matter volume and measures of cannabis and tobacco use. Results: A significant group effect was observed in the left putamen, thalamus, right precentral gyrus, and left cerebellum. Compared to HCs, the Cs, CTs, and Ts exhibited larger gray matter volumes in the left putamen. Cs also had larger gray matter volume than HCs in the right precentral gyrus. Cs and CTs exhibited smaller gray matter volume than HCs in the thalamus, and CTs and Ts had smaller left cerebellar gray matter volume than HCs. Conclusions: This study extends previous research that independently examined the effects of cannabis or tobacco use on brain structure by including an examination of co-occurring cannabis and tobacco use, and provides evidence that cannabis and tobacco exposure are associated with alterations in brain regions associated with addiction. PMID:26045474

  3. Cannabis use, gender and age of onset of schizophrenia: data from the ÆSOP study.

    PubMed

    Donoghue, Kim; Doody, Gillian A; Murray, Robin M; Jones, Peter B; Morgan, Craig; Dazzan, Paola; Hart, Jozella; Mazzoncini, Rodolfo; Maccabe, James H

    2014-03-30

    An earlier age of onset of schizophrenia has been identified as a poor prognostic indicator. The current study examines the interaction effect of gender and cannabis use on age of onset of schizophrenia and schizoaffective disorder. This research forms part of a two-centre epidemiological study of first-episode psychosis and included individuals with a diagnosis of schizophrenia or schizoaffective disorder and an age of onset between age 16 and 45. Kaplan-Meier curves and Cox proportional hazards regression were used to compare the effects of cannabis use and gender on age of first symptom of schizophrenia. Akaike's information criteria were used to find the model with the best fit to the data. Cannabis users had an earlier age of first symptom than non-users. There was an interaction with gender; the gender difference in age of onset was diminished in cannabis smokers compared with non-cannabis smokers. The model including cannabis use interacting with gender was the most parsimonious model, followed by cannabis use alone. The addition of other illegal drug use did not improve the model. Cannabis use is associated with an earlier age of onset of schizophrenia, and the gender difference in age of onset is reduced among cannabis smokers.

  4. Sleep disturbance and the effects of extended-release zolpidem during cannabis withdrawal

    PubMed Central

    Vandrey, Ryan; Smith, Michael T.; McCann, Una D.; Budney, Alan J.; Curran, Erin M.

    2011-01-01

    Background Sleep difficulty is a common symptom of cannabis withdrawal, but little research has objectively measured sleep or explored the effects of hypnotic medication on sleep during cannabis withdrawal. Methods Twenty daily cannabis users completed a within-subject crossover study. Participants alternated between periods of ad-libitum cannabis use and short-term cannabis abstinence (3 days). Placebo was administered at bedtime during one abstinence period (withdrawal test) and extended-release zolpidem, a non-benzodiazepine GABAA receptor agonist, was administered during the other. Polysomnographic (PSG) sleep architecture measures, subjective ratings, and cognitive performance effects were assessed each day. Results During the placebo-abstinence period, participants had decreased sleep efficiency, total sleep time, percent time spent in Stage 1 and Stage 2 sleep, REM latency and subjective sleep quality, as well as increased sleep latency and time spent in REM sleep compared with when they were using cannabis. Zolpidem attenuated the effects of abstinence on sleep architecture and normalized sleep efficiency scores, but had no effect on sleep latency. Zolpidem was not associated with any significant side effects or next-day cognitive performance impairments. Conclusions These data extend prior research that indicates abrupt abstinence from cannabis can lead to clinically significant sleep disruption in daily users. The findings also indicate that sleep disruption associated with cannabis withdrawal can be attenuated by zolpidem, suggesting that hypnotic medications might be useful adjunct pharmacotherapies in the treatment of cannabis use disorders. PMID:21296508

  5. [Cannabis--abuse and consequences].

    PubMed

    Wøien, Vidar-André; Horwitz, Henrik; Høgberg, Lotte C G; Askaa, Bjarke; Jürgens, Gesche

    2015-02-01

    Cannabis is the world's most popular illicit drug, and around half of all Danes have tried it at least once. In this paper we review the pharmacodynamic and pharmacokinetic properties of cannabis. We also discuss the treatment of cannabis intoxication and present data from The Danish Poison Information Center. PMID:25650575

  6. Neuropsychological Performance in Adolescent Marijuana Users with Co-Occurring Alcohol Use: A Three-Year Longitudinal Study

    PubMed Central

    Jacobus, Joanna; Squeglia, Lindsay M.; Infante, M. Alejandra; Castro, Norma; Brumback, Ty; Meruelo, Alejandro D.; Tapert, Susan F.

    2015-01-01

    Objective The effect of adolescent marijuana use on brain development remains unclear despite relaxing legal restrictions, decreased perceived harm, and increasing use rates among youth. The aim of this 3-year prospective study was to evaluate the long-term neurocognitive effects of adolescent marijuana use. Method Adolescent marijuana users with concomitant alcohol use (MJ+ALC, n=49) and control teens with limited substance use histories (CON, n=59) were given neuropsychological and substance use assessments at project baseline, when they were ages 16-19. They were then re-assessed 18 and 36 months later. Changes in neuropsychological measures were evaluated with repeated measures analysis of covariance (ANCOVA), controlling for lifetime alcohol use, and examined the effects of group, time, and group by time interactions on cognitive functioning. Results MJ+ALC users performed significantly worse than controls, across time points, in the domains of complex attention, memory, processing speed, and visuospatial functioning (ps<.05). Earlier age of marijuana use onset was associated with poorer processing speed and executive functioning by the 3-year follow-up (ps≤.02). Conclusions Frequent marijuana use throughout adolescence and into young adulthood appeared linked to worsened cognitive performance. Earlier age of onset appears to be associated with poorer neurocognitive outcomes that emerge by young adulthood, providing further support for the notion that the brain may be uniquely sensitive to frequent marijuana exposure during the adolescent phase of neurodevelopment. Continued follow-up of adolescent marijuana users will determine the extent of neural recovery that may occur if use abates. PMID:25938918

  7. Cannabis and psychotic illness.

    PubMed

    Mathers, D C; Ghodse, A H

    1992-11-01

    In-patients with psychotic symptoms and cannabis-positive urine analysis were assessed by PSE within one week of admission and again at one and six months. Concurrently admitted psychotic patients with drug-free urine analysis were controls. At one week the two groups differed significantly on only five PSE items: changed perception, thought insertion, non-verbal auditory hallucinations, delusions of control, and delusions of grandiose ability. One item (delayed sleep) differed at one month, and none at six months. The symptom cluster at one week is consistent with acute cannabis intoxication. Subjects and controls were mostly single, poorly educated, unemployed people with histories of psychotic disorders, and given major tranquillisers on admission. Compared with controls, subjects were younger, less likely to have psychiatric histories, more often male, Afro-Caribbeans with a history of convictions and compulsory admissions. The commonest diagnosis was schizophrenia. Use of the label 'cannabis-induced psychosis' may obscure a diagnosis of paranoid schizophrenia. A short-lived psychotic episode does occur in clear consciousness after cannabis intoxication, but chronic cannabis-induced psychosis was not found.

  8. [Cannabis--Position Paper of the German Respiratory Society (DGP)].

    PubMed

    Kreuter, M; Nowak, D; Rüther, T; Hoch, E; Thomasius, R; Vogelberg, C; Brockstedt, M; Hellmann, A; Gohlke, H; Jany, B; Loddenkemper, R

    2016-02-01

    In this position paper, the adverse health effects of cannabis are reviewed based on the existing scientific literature; in addition possible symptom-relieving effects on some diseases are depicted. In Germany, cannabis is the most widely used illicit drug. Approximately 600,000 adult persons show abusive or addictive cannabis consumption. In 12 to 17 year old adolescents, cannabis use increased from 2011 to 2014 from 2.8 to 6.4%, and the frequency of regular use from 0.2 to 1.5%. Currently, handling of cannabinoids is much debated in politics as well as in general public. Health aspects have to be incorporated into this debate. Besides analysing mental and neurological side effects, this position paper will mainly focus on the influences on the bronchopulmonary and cardiovascular system. There is strong evidence for the induction of chronic bronchitis. Allergic reactions including asthma are known, too. Associations with other diseases like pulmonary emphysema, lung cancer and pneumonia are not sufficiently proven, however cannot be excluded either. In connection with the use of cannabis cardiovascular events such as coronary syndromes, peripheral vascular diseases and cerebral complications have been noted. Often, the evidence is insufficient due to various reasons; most notably, the overlapping effects of tobacco and cannabis use can frequently not be separated adequately. Empirically, early beginning, high-dosed, long-lasting and regular cannabis consumption increase the risk of various psychological and physical impairments and negatively affect age-based development. Concerns therefore relate especially to children and adolescents. There is only little scientific evidence for medical benefits through cannabis as a remedy; systematic research of good quality, in particular prospective, randomised, placebo-controlled double-blinded studies are rare. The medical societies signing this position paper conclude that cannabis consumption is linked to adverse health

  9. [Cannabis--Position Paper of the German Respiratory Society (DGP)].

    PubMed

    Kreuter, M; Nowak, D; Rüther, T; Hoch, E; Thomasius, R; Vogelberg, C; Brockstedt, M; Hellmann, A; Gohlke, H; Jany, B; Loddenkemper, R

    2016-02-01

    In this position paper, the adverse health effects of cannabis are reviewed based on the existing scientific literature; in addition possible symptom-relieving effects on some diseases are depicted. In Germany, cannabis is the most widely used illicit drug. Approximately 600,000 adult persons show abusive or addictive cannabis consumption. In 12 to 17 year old adolescents, cannabis use increased from 2011 to 2014 from 2.8 to 6.4%, and the frequency of regular use from 0.2 to 1.5%. Currently, handling of cannabinoids is much debated in politics as well as in general public. Health aspects have to be incorporated into this debate. Besides analysing mental and neurological side effects, this position paper will mainly focus on the influences on the bronchopulmonary and cardiovascular system. There is strong evidence for the induction of chronic bronchitis. Allergic reactions including asthma are known, too. Associations with other diseases like pulmonary emphysema, lung cancer and pneumonia are not sufficiently proven, however cannot be excluded either. In connection with the use of cannabis cardiovascular events such as coronary syndromes, peripheral vascular diseases and cerebral complications have been noted. Often, the evidence is insufficient due to various reasons; most notably, the overlapping effects of tobacco and cannabis use can frequently not be separated adequately. Empirically, early beginning, high-dosed, long-lasting and regular cannabis consumption increase the risk of various psychological and physical impairments and negatively affect age-based development. Concerns therefore relate especially to children and adolescents. There is only little scientific evidence for medical benefits through cannabis as a remedy; systematic research of good quality, in particular prospective, randomised, placebo-controlled double-blinded studies are rare. The medical societies signing this position paper conclude that cannabis consumption is linked to adverse health

  10. Identifying Problematic Internet Users: Development and Validation of the Internet Motive Questionnaire for Adolescents (IMQ-A)

    PubMed Central

    Bischof-Kastner, Christina; Kuntsche, Emmanuel

    2014-01-01

    Background Internationally, up to 15.1% of intensive Internet use among adolescents is dysfunctional. To provide a basis for early intervention and preventive measures, understanding the motives behind intensive Internet use is important. Objective This study aims to develop a questionnaire, the Internet Motive Questionnaire for Adolescents (IMQ-A), as a theory-based measurement for identifying the underlying motives for high-risk Internet use. More precisely, the aim was to confirm the 4-factor structure (ie, social, enhancement, coping, and conformity motives) as well as its construct and concurrent validity. Another aim was to identify the motivational differences between high-risk and low-risk Internet users. Methods A sample of 101 German adolescents (female: 52.5%, 53/101; age: mean 15.9, SD 1.3 years) was recruited. High-risk users (n=47) and low-risk users (n=54) were identified based on a screening measure for online addiction behavior in children and adolescents (Online-Suchtverhalten-Skala, OSVK-S). Here, “high-risk” Internet use means use that exceeds the level of intensive Internet use (OSVK-S sum score ≥7). Results The confirmatory factor analysis confirmed the IMQ-A’s 4-factor structure. A reliability analysis revealed good internal consistencies of the subscales (.71 up to .86). Moreover, regression analyses confirmed that the enhancement and coping motive groups significantly predicted high-risk Internet consumption and the OSVK-S sum score. A mixed-model ANOVA confirmed that adolescents mainly access the Internet for social motives, followed by enhancement and coping motives, and that high-risk users access the Internet more frequently for coping and enhancement motives than low-risk users. Low-risk users were primarily motivated socially. Conclusions The IMQ-A enables the assessment of motives related to adolescent Internet use and thus the identification of populations at risk. The questionnaire enables the development of preventive

  11. Adolescence, sexual behavior and risk factors to health

    PubMed Central

    de Assis, Simone Gonçalves; Gomes, Romeu; Pires, Thiago de Oliveira

    2014-01-01

    OBJECTIVE To analyze the relationships between sexual behavior and risk factors to physical and mental health in adolescents. METHODS Study of 3,195 pupils aged 15 to 19 in secondary education, in public and private schools in 10 state capitals in Brazil between 2007 and 2008. Multi-stage (schools and pupils) cluster sampling was used in each city and public and private educational network. All of the students selected completed a questionnaire on the following items: socioeconomic and demographic data; sexual behavior; having sex with those of the same sex, the opposite sex, or both; alcohol and cannabis use; using condoms; traumatic sexual experiences as a child or adolescent; suicidal thoughts. The analysis included describing frequencies, Chi-square test, analysis of multiple and cluster correspondence. Responses to an open ended question in which the adolescent expressed general comments about themselves and their lives were qualitatively analyzed using content analysis. RESULTS Around 3.0% of adolescents reported homosexual or bisexual behavior, with no difference according to sex, age, skin color, social status family structure or educational network. Adolescents with homosexual/bisexual sexual behavior, compared to their heterosexual peers, reported: (p < 0.05): getting drunk (18.7% and 10.5%, respectively), frequent cannabis use (6.1% and 2.1%, respectively), suicidal thoughts (42.5% and 18.7%, respectively), and having been the victim of sexual violence (11.7% and 1.5%; respectively). Adolescents with homosexual/bisexual sexual behavior reported that they used condoms less frequently (74.2%) than their heterosexual peers (48.6%, p < 0.001). In the correspondence analysis, three groups were found, one composed of adolescents with homosexual/bisexual behavior and experiencing risk factors; suffering sexual violence, never using a condom, suicidal thoughts, frequent cannabis use; another composed of occasional cannabis and condom users, who got drunk

  12. A longitudinal study of cannabis use initiation among high school students: Effects of social anxiety, expectancies, peers and alcohol.

    PubMed

    Schmits, Emilie; Mathys, Cécile; Quertemont, Etienne

    2015-06-01

    This study identified protective and risk factors of cannabis use initiation, including expectancies and social anxiety. A questionnaire was completed twice by 877 teenagers. Logistic regressions, mediation and moderation analyses were performed. Significant risk factors were alcohol use, peer users, perceptual enhancement, and craving expectancies. Protective factors were negative behavior expectancies and social anxiety. Social anxiety protected from initiation through the mediating role of perceptual enhancement and craving expectancies, whatever the role of peer users and alcohol use. Findings are discussed in terms of risk and protection, in an overall approach including internalizing factors. Results support the identification of an internalizing profile of adolescents for prevention or treatment and the importance of social anxiety and expectancies in intervention.

  13. Pharmacotherapies for cannabis dependence

    PubMed Central

    Marshall, Kushani; Gowing, Linda; Ali, Robert; Le Foll, Bernard

    2015-01-01

    Background Cannabis is the most prevalent illicit drug in the world. Demand for treatment of cannabis use disorders is increasing. There are currently no pharmacotherapies approved for treatment of cannabis use disorders. Objectives To assess the effectiveness and safety of pharmacotherapies as compared with each other, placebo or supportive care for reducing symptoms of cannabis withdrawal and promoting cessation or reduction of cannabis use. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (to 4 March 2014), MEDLINE (to week 3 February 2014), EMBASE (to 3 March 2014) and PsycINFO (to week 4 February 2014). We also searched reference lists of articles, electronic sources of ongoing trials and conference proceedings, and contacted selected researchers active in the area. Selection criteria Randomised and quasi-randomised controlled trials involving the use of medications to reduce the symptoms and signs of cannabis withdrawal or to promote cessation or reduction of cannabis use, or both, in comparison with other medications, placebo or no medication (supportive care) in participants diagnosed as cannabis dependent or who were likely to be dependent. Data collection and analysis We used standard methodological procedures expected by The Cochrane Collaboration. Two review authors assessed studies for inclusion and extracted data. All review authors confirmed the inclusion decisions and the overall process. Main results We included 14 randomised controlled trials involving 958 participants. For 10 studies the average age was 33 years; two studies targeted young people; and age data were not available for two studies. Approximately 80% of study participants were male. The studies were at low risk of selection, performance, detection and selective outcome reporting bias. Three studies were at risk of attrition bias. All studies involved comparison of active medication and placebo. The medications included preparations containing

  14. Individual differences in decision making and reward processing predict changes in cannabis use: a prospective functional magnetic resonance imaging study.

    PubMed

    Cousijn, Janna; Wiers, Reinout W; Ridderinkhof, K Richard; van den Brink, Wim; Veltman, Dick J; Porrino, Linda J; Goudriaan, Anna E

    2013-11-01

    Decision-making deficits are thought to play an important role in the development and persistence of substance use disorders. Individual differences in decision-making abilities and their underlying neurocircuitry may, therefore, constitute an important predictor for the course of substance use and the development of substance use disorders. Here, we investigate the predictive value of decision making and neural mechanisms underlying decision making for future cannabis use and problem severity in a sample of heavy cannabis users. Brain activity during a monetary decision-making task (Iowa gambling task) was compared between 32 heavy cannabis users and 41 matched non-using controls using functional magnetic resonance imaging. In addition, within the group of heavy cannabis users, associations were examined between task-related brain activations, cannabis use and cannabis use-related problems at baseline, and change in cannabis use and problem severity after a 6-month follow-up. Despite normal task performance, heavy cannabis users compared with controls showed higher activation during wins in core areas associated with decision making. Moreover, within the group of heavy cannabis users, win-related activity and activity anticipating loss outcomes in areas generally involved in executive functions predicted change in cannabis use after 6 months. These findings are consistent with previous studies and point to abnormal processing of motivational information in heavy cannabis users. A new finding is that individuals who are biased toward immediate rewards have a higher probability of increasing drug use, highlighting the importance of the relative balance between motivational processes and regulatory executive processes in the development of substance use disorders.

  15. Predicting creativity: the role of psychometric schizotypy and cannabis use in divergent thinking.

    PubMed

    Minor, Kyle S; Firmin, Ruth L; Bonfils, Kelsey A; Chun, Charlotte A; Buckner, Julia D; Cohen, Alex S

    2014-12-15

    Evidence suggests that divergent thinking (DT), a measure of creativity, is associated with positive schizotypy and cannabis use. Given the high rates of cannabis use among those with schizotypy, it is unclear if the relation of DT to schizotypy is due to co-occurring cannabis use. In this study, we examined the relations between DT, schizotypy, and cannabis use among positive schizotypy (n=66), negative schizotypy (n=22), and non-schizotypy (n=60) groups. Results revealed that DT was greater in the positive schizotypy group, on the order of small to medium effects, compared to negative and non-schizotypy groups. Cannabis use and DT were associated in the non-schizotypy group, but not in the positive or negative schizotypy groups. Across all groups, positive schizotypy significantly predicted DT; however, cannabis use was not a significant predictor of DT. In line with previous findings, cannabis use and DT were only related in individuals low in creativity. This suggests that a ceiling effect may be present, with only cannabis users who are low in creativity receiving any increase in DT. Future research should aim to clarify the DT-cannabis relationship.

  16. [Frequent non-medical cannabis use: health sequelae and effectiveness of detoxification treatment].

    PubMed

    Bonnet, Udo; Specka, Michael; Scherbaum, Norbert

    2016-01-01

    The non-medical (recreational) use of cannabis is common particularly among young adults. In light of the ongoing legalization debate the clinical impact of physical and psychosocial consequences of regular recreational cannabis consumption should be presented. Health consequences appear to be more pronounced the earlier the regular recreational cannabis use had been started in the individual's development. There is an increasing demand from recreational cannabis users for medical treatment of cannabis-related complaints including the cannabis withdrawal syndrome. Physical sequelae such as chronic bronchitis, cyclical hyperemesis and fertility problems are usually reversible along with abstinence. The often debilitating cannabis-related mental and cognitive complaints respond on a qualified inpatient detoxification treatment with high effect sizes (Cohen's d 0.7 -1.4). The severity of the cannabis addiction benefits sustainably from psychotherapeutic approaches and individual psychosocial counseling (Cohen's d 0,5-1,2). Currently, the actual health hazard of recreational cannabis use was evaluated by addiction experts to be significantly lower than that of tobacco or alcohol use.

  17. [Frequent non-medical cannabis use: health sequelae and effectiveness of detoxification treatment].

    PubMed

    Bonnet, Udo; Specka, Michael; Scherbaum, Norbert

    2016-01-01

    The non-medical (recreational) use of cannabis is common particularly among young adults. In light of the ongoing legalization debate the clinical impact of physical and psychosocial consequences of regular recreational cannabis consumption should be presented. Health consequences appear to be more pronounced the earlier the regular recreational cannabis use had been started in the individual's development. There is an increasing demand from recreational cannabis users for medical treatment of cannabis-related complaints including the cannabis withdrawal syndrome. Physical sequelae such as chronic bronchitis, cyclical hyperemesis and fertility problems are usually reversible along with abstinence. The often debilitating cannabis-related mental and cognitive complaints respond on a qualified inpatient detoxification treatment with high effect sizes (Cohen's d 0.7 -1.4). The severity of the cannabis addiction benefits sustainably from psychotherapeutic approaches and individual psychosocial counseling (Cohen's d 0,5-1,2). Currently, the actual health hazard of recreational cannabis use was evaluated by addiction experts to be significantly lower than that of tobacco or alcohol use. PMID:26800074

  18. Cannabis use and mental health-related quality of life among individuals with depressive disorders.

    PubMed

    Aspis, Itay; Feingold, Daniel; Weiser, Mark; Rehm, Jurgen; Shoval, Gal; Lev-Ran, Shaul

    2015-12-15

    Cannabis is the most widely used illicit substance among individuals with depressive disorders. This study aimed to evaluate whether among individuals with depressive disorders, higher frequency of cannabis use would be associated with poorer Quality of Life (QoL), based on a large nationally representative US sample. Individuals with depressive disorders (N=3416) were divided into categories according to no use (N=3096), occasional use (less than weekly, N=176) and regular (at least weekly, N=144) use of cannabis in the past 12 months. QoL was assessed using the Short-Form 12 (SF-12) questionnaire. Women who used cannabis regularly had a significantly lower SF-12 Mental Component Summary score (MCS) compared to non-users, with a mean difference of 0.4 Standard Deviations (SDs). Comparison of subscale scores showed no significant differences. No significant difference was noted when comparing women who used cannabis occasionally to non-users. No differences were found among men when comparing MCS and mental subscale scores of both regular and occasional users to non-users. Our findings highlight the importance of taking gender and the frequency of cannabis use into account, when assessing functional and emotional aspects of cannabis use among individuals with depressive disorders.

  19. Cannabis use and mental health-related quality of life among individuals with depressive disorders.

    PubMed

    Aspis, Itay; Feingold, Daniel; Weiser, Mark; Rehm, Jurgen; Shoval, Gal; Lev-Ran, Shaul

    2015-12-15

    Cannabis is the most widely used illicit substance among individuals with depressive disorders. This study aimed to evaluate whether among individuals with depressive disorders, higher frequency of cannabis use would be associated with poorer Quality of Life (QoL), based on a large nationally representative US sample. Individuals with depressive disorders (N=3416) were divided into categories according to no use (N=3096), occasional use (less than weekly, N=176) and regular (at least weekly, N=144) use of cannabis in the past 12 months. QoL was assessed using the Short-Form 12 (SF-12) questionnaire. Women who used cannabis regularly had a significantly lower SF-12 Mental Component Summary score (MCS) compared to non-users, with a mean difference of 0.4 Standard Deviations (SDs). Comparison of subscale scores showed no significant differences. No significant difference was noted when comparing women who used cannabis occasionally to non-users. No differences were found among men when comparing MCS and mental subscale scores of both regular and occasional users to non-users. Our findings highlight the importance of taking gender and the frequency of cannabis use into account, when assessing functional and emotional aspects of cannabis use among individuals with depressive disorders. PMID:26388103

  20. Cannabis and psychosis revisited.

    PubMed

    Damjanović, Aleksandar; Pantović, Maja; Damjanović, Aleksandra; Dunjić-Kostić, Bojana; Ivković, Maja; Milovanović, Srđan; Lacković, Maja; Dimitrijević, Ivan

    2015-03-01

    The association between cannabinoids and psychosis has been known for almost a thousand years, but it is still speculated whether cannabis use may be a contributory cause of psychosis, that is, whether it may precipitate schizophrenia in those at risk. In this paper, we will briefly present the data from individual longitudinal studies in the field, together with the factors that are considered important for the association of cannabis abuse and occurrence of schizophrenia and prevention opportunities in the target population. The reviewed studies clearly suggest that cannabis abuse predicts an increased risk for schizophrenia, particularly in young adults. They underline both the need to create adequate prevention measures and consequently avoid the occurrence of the disease in the young at risk. Particular attention should be additionally devoted toward encouraging the young presenting with psychotic symptoms to stop or, at the very least, reduce the frequency of cannabis abuse. The issues are undoubtedly to be addressed by the health care system in general. PMID:25751443

  1. Cannabis and psychosis: Neurobiology.

    PubMed

    Shrivastava, Amresh; Johnston, Megan; Terpstra, Kristen; Bureau, Yves

    2014-01-01

    Cannabis is a known risk factor for schizophrenia, although the exact neurobiological process through which the effects on psychosis occur is not well-understood. In this review, we attempt to develop and discuss a possible pathway for the development of psychosis. We examine the neurobiological changes due to cannabis to see if these changes are similar to those seen in schizophrenic patients the findings show similarities; however, these mere similarities cannot establish a 'cause-effect' relationship as a number of people with similar changes do not develop schizophrenia. Therefore, the 'transition-to-psychosis' due to cannabis, despite being a strong risk factor, remains uncertain based upon neurobiological changes. It appears that other multiple factors might be involved in these processes which are beyond neurobiological factors. Major advances have been made in understanding the underpinning of marijuana dependence, and the role of the cannabinoid system, which is a major area for targeting medications to treat marijuana withdrawal and dependence, as well as other addictions is of now, it is clear that some of the similarities in the neurobiology of cannabis and schizophrenia may indicate a mechanism for the development of psychosis, but its trajectories are undetermined. PMID:24574553

  2. Social Representations Used by the Parents of Mexican Adolescent Drug Users under Treatment to Explain Their Children's Drug Use: Gender Differences in Parental Narratives

    ERIC Educational Resources Information Center

    Nuno-Gutierrez, Bertha Lidia; Alvarez-Nemegyei, Jose; Rodriguez-Cerda, Oscar

    2008-01-01

    The aim of this study was to explore the social representations used by the parents of adolescent drug users to explain the onset of drug use. Differences in explanations between the parents of male and female adolescents were also explored. Sixty parents who accompanied their children to four rehabilitation centers in 2004 completed two…

  3. Burnout among High-School Students and Cannabis Use, Consumption Frequencies, Abuse and Dependence

    ERIC Educational Resources Information Center

    Walburg, Vera; Moncla, Dany; Mialhes, Aurélie

    2015-01-01

    Background: Cannabis is a substance frequently consumed by adolescents, which is a risk factor for many psychopathological disorders. At the same time, adolescents in high-schools are likely to be exposed to significant stress from school that can sometimes lead to a burnout syndrome. Objective: The purpose of this study is to explore the impact…

  4. Externalizing Behavior Problems and Cigarette Smoking as Predictors of Cannabis Use: The TRAILS Study

    ERIC Educational Resources Information Center

    Korhonen, Tellervo; van Leeuwen, Andrea Prince; Reijneveld, Sijmen A.; Ormel, Johan; Verhulst, Frank C.; Huizink, Anja C.

    2010-01-01

    Objective: To examine externalizing behavior problems and cigarette smoking as predictors of subsequent cannabis use. Method: Dutch adolescents (N = 1,606; 854 girls and 752 boys) from the TRacking Adolescents' Individual Lives Survey (TRAILS) ongoing longitudinal study were examined at baseline (ages 10-12 [T1]) and at two follow-up assessments…

  5. Traditional marijuana, high‐potency cannabis and synthetic cannabinoids: increasing risk for psychosis

    PubMed Central

    Murray, Robin M.; Quigley, Harriet; Quattrone, Diego; Englund, Amir; Di Forti, Marta

    2016-01-01

    Epidemiological evidence demonstrates that cannabis use is associated with an increased risk of psychotic outcomes, and confirms a dose‐response relationship between the level of use and the risk of later psychosis. High‐potency cannabis and synthetic cannabinoids carry the greatest risk. Experimental administration of tetrahydrocannabinol, the active ingredient of cannabis, induces transient psychosis in normal subjects, but this effect can be ameliorated by co‐administration of cannabidiol. This latter is a constituent of traditional hashish, but is largely absent from modern high‐potency forms of cannabis. Argument continues over the extent to which genetic predisposition is correlated to, or interacts with, cannabis use, and what proportion of psychosis could be prevented by minimizing heavy use. As yet, there is not convincing evidence that cannabis use increases risk of other psychiatric disorders, but there are no such doubts concerning its detrimental effect on cognitive function. All of the negative aspects are magnified if use starts in early adolescence. Irrespective of whether use of cannabis is decriminalized or legalized, the evidence that it is a component cause of psychosis is now sufficient for public health messages outlining the risk, especially of regular use of high‐potency cannabis and synthetic cannabinoids. PMID:27717258

  6. Traditional marijuana, high‐potency cannabis and synthetic cannabinoids: increasing risk for psychosis

    PubMed Central

    Murray, Robin M.; Quigley, Harriet; Quattrone, Diego; Englund, Amir; Di Forti, Marta

    2016-01-01

    Epidemiological evidence demonstrates that cannabis use is associated with an increased risk of psychotic outcomes, and confirms a dose‐response relationship between the level of use and the risk of later psychosis. High‐potency cannabis and synthetic cannabinoids carry the greatest risk. Experimental administration of tetrahydrocannabinol, the active ingredient of cannabis, induces transient psychosis in normal subjects, but this effect can be ameliorated by co‐administration of cannabidiol. This latter is a constituent of traditional hashish, but is largely absent from modern high‐potency forms of cannabis. Argument continues over the extent to which genetic predisposition is correlated to, or interacts with, cannabis use, and what proportion of psychosis could be prevented by minimizing heavy use. As yet, there is not convincing evidence that cannabis use increases risk of other psychiatric disorders, but there are no such doubts concerning its detrimental effect on cognitive function. All of the negative aspects are magnified if use starts in early adolescence. Irrespective of whether use of cannabis is decriminalized or legalized, the evidence that it is a component cause of psychosis is now sufficient for public health messages outlining the risk, especially of regular use of high‐potency cannabis and synthetic cannabinoids.

  7. Distance to Cannabis Shops and Age of Onset of Cannabis Use.

    PubMed

    Palali, Ali; van Ours, Jan C

    2015-11-01

    In the Netherlands, cannabis use is quasi-legalized. Small quantities of cannabis can be bought in cannabis shops. We investigate how the distance to the nearest cannabis shop affects the age of onset of cannabis use. We use a mixed proportional hazard rate framework to take account of observable as well as unobservable characteristics that influence the uptake of cannabis. We find that distance matters. Individuals who grow up within 20 km of a cannabis shop have a lower age of onset.

  8. Cannabis Effects on Driving Skills

    PubMed Central

    Hartman, Rebecca L.; Huestis, Marilyn A.

    2013-01-01

    BACKGROUND Cannabis is the most prevalent illicit drug identified in impaired drivers. The effects of cannabis on driving continue to be debated, making prosecution and legislation difficult. Historically, delays in sample collection, evaluating the inactive Δ9-tetrahydrocannabinol (THC) metabolite 11-nor-9-carboxy-THC, and polydrug use have complicated epidemiologic evaluations of driver impairment after cannabis use. CONTENT We review and evaluate the current literature on cannabis’ effects on driving, highlighting the epidemiologic and experimental data. Epidemiologic data show that the risk of involvement in a motor vehicle accident (MVA) increases approximately 2-fold after cannabis smoking. The adjusted risk of driver culpability also increases substantially, particularly with increased blood THC concentrations. Studies that have used urine as the biological matrix have not shown an association between cannabis and crash risk. Experimental data show that drivers attempt to compensate by driving more slowly after smoking cannabis, but control deteriorates with increasing task complexity. Cannabis smoking increases lane weaving and impaired cognitive function. Critical-tracking tests, reaction times, divided-attention tasks, and lane-position variability all show cannabis-induced impairment. Despite purported tolerance in frequent smokers, complex tasks still show impairment. Combining cannabis with alcohol enhances impairment, especially lane weaving. SUMMARY Differences in study designs frequently account for inconsistencies in results between studies. Participant-selection bias and confounding factors attenuate ostensible cannabis effects, but the association with MVA often retains significance. Evidence suggests recent smoking and/or blood THC concentrations 2–5 ng/mL are associated with substantial driving impairment, particularly in occasional smokers. Future cannabis-and-driving research should emphasize challenging tasks, such as divided attention

  9. A Longitudinal Study of Speech Perception Skills and Device Characteristics of Adolescent Cochlear Implant Users

    PubMed Central

    Robinson, Elizabeth J.; Davidson, Lisa S.; Uchanski, Rosalie M.; Brenner, Christine M.; Geers, Ann E.

    2012-01-01

    Background For pediatric cochlear implant (CI) users, CI processor technology, map characteristics and fitting strategies are known to have a substantial impact on speech perception scores at young ages. It is unknown whether these benefits continue over time as these children reach adolescence. Purpose To document changes in CI technology, map characteristics, and speech perception scores in children between elementary grades and high school, and to describe relations between map characteristics and speech perception scores over time. Research Design A longitudinal design with participants 8–9 years old at session 1 and 15–18 years old at session 2. Study Sample Participants were 82 adolescents with unilateral CIs, who are a subset of a larger longitudinal study. Mean age at implantation was 3.4 years (range: 1.7 – 5.4), and mean duration of device use was 5.5 years (range: 3.8–7.5) at session 1 and 13.3 years (range: 10.9–15) at session 2. Data Collection and Analysis Speech perception tests at sessions 1 and 2 were the Lexical Neighborhood word Test (LNT-70) and Bamford-Kowal-Bench sentences in quiet (BKB-Q), presented at 70 dB SPL. At session 2, the LNT was also administered at 50 dB SPL (LNT-50) and BKB sentences were administered in noise with a +10 dB SNR (BKB-N). CI processor technology type and CI map characteristics (coding strategy, number of electrodes, map threshold levels [T levels], and map comfort levels [C levels]) were obtained at both sessions. Electrical dynamic range [EDR] was computed [C level – T level], and descriptive statistics, correlations, and repeated-measures ANOVAs were employed. Results Participants achieved significantly higher LNT and BKB scores, at 70 dB SPL, at ages 15-18 than at ages 8-9 years. Forty-two participants had 1-3 electrodes either activated or deactivated in their map between test sessions, and 40 had no change in number of active electrodes (mean change: -0.5; range: -3 to +2). After conversion from

  10. Cannabis - from cultivar to chemovar.

    PubMed

    Hazekamp, A; Fischedick, J T

    2012-01-01

    The medicinal use of Cannabis is increasing as countries worldwide are setting up official programs to provide patients with access to safe sources of medicinal-grade Cannabis. An important question that remains to be answered is which of the many varieties of Cannabis should be made available for medicinal use. Drug varieties of Cannabis are commonly distinguished through the use of popular names, with a major distinction being made between Indica and Sativa types. Although more than 700 different cultivars have already been described, it is unclear whether such classification reflects any relevant differences in chemical composition. Some attempts have been made to classify Cannabis varieties based on chemical composition, but they have mainly been useful for forensic applications, distinguishing drug varieties, with high THC content, from the non-drug hemp varieties. The biologically active terpenoids have not been included in these approaches. For a clearer understanding of the medicinal properties of the Cannabis plant, a better classification system, based on a range of potentially active constituents, is needed. The cannabinoids and terpenoids, present in high concentrations in Cannabis flowers, are the main candidates. In this study, we compared cultivars obtained from multiple sources. Based on the analysis of 28 major compounds present in these samples, followed by principal component analysis (PCA) of the quantitative data, we were able to identify the Cannabis constituents that defined the samples into distinct chemovar groups. The study indicates the usefulness of a PCA approach for chemotaxonomic classification of Cannabis varieties.

  11. Cannabis use is associated with increased CCL11 plasma levels in young healthy volunteers.

    PubMed

    Fernandez-Egea, Emilio; Scoriels, Linda; Theegala, Swathi; Giro, Maria; Ozanne, Susan E; Burling, Keith; Jones, Peter B

    2013-10-01

    Cannabis is a widely used recreational drug. Its effect on human health and psychosis remains controversial. In this study, we aimed to explore the possibility that cannabis use influenced CCL11 plasma levels. Increased CCL11 chemokine has been reported in schizophrenia and cannabis is a known trigger of schizophrenia. Additionally, plasma levels of the chemokine CCL11 have recently been shown to increase with age and with cognitive deficits and hippocampal neurogenesis. For this study, a total of 87 healthy volunteers (68% men, age range 18-35 years) completed the Cannabis Experience Questionnaire that included information on sociodemographic and morphometric data and provided a blood sample for CCL11 measurement. 'Current users' of cannabis (n=18) had significantly higher CCL11 plasma levels compared to 'past users' (n=33) and 'never users' (n=36) [F(3,84)=3.649; p=0.030]. The latter two groups had similar CCL11 levels. Higher CCL11 plasma levels could not be attributed to gender, age, body mass index, physical activity or use of other legal/illegal drugs. These results suggest that cannabis use increases CCL11 plasma levels and the effects are reversible when cannabis use ceases. PMID:23820464

  12. Cannabis use is associated with increased CCL11 plasma levels in young healthy volunteers.

    PubMed

    Fernandez-Egea, Emilio; Scoriels, Linda; Theegala, Swathi; Giro, Maria; Ozanne, Susan E; Burling, Keith; Jones, Peter B

    2013-10-01

    Cannabis is a widely used recreational drug. Its effect on human health and psychosis remains controversial. In this study, we aimed to explore the possibility that cannabis use influenced CCL11 plasma levels. Increased CCL11 chemokine has been reported in schizophrenia and cannabis is a known trigger of schizophrenia. Additionally, plasma levels of the chemokine CCL11 have recently been shown to increase with age and with cognitive deficits and hippocampal neurogenesis. For this study, a total of 87 healthy volunteers (68% men, age range 18-35 years) completed the Cannabis Experience Questionnaire that included information on sociodemographic and morphometric data and provided a blood sample for CCL11 measurement. 'Current users' of cannabis (n=18) had significantly higher CCL11 plasma levels compared to 'past users' (n=33) and 'never users' (n=36) [F(3,84)=3.649; p=0.030]. The latter two groups had similar CCL11 levels. Higher CCL11 plasma levels could not be attributed to gender, age, body mass index, physical activity or use of other legal/illegal drugs. These results suggest that cannabis use increases CCL11 plasma levels and the effects are reversible when cannabis use ceases.

  13. Individual Characteristics of Adolescent Methamphetamine Users in Relation to Self-Reported Trouble with the Police

    ERIC Educational Resources Information Center

    Gassman, Ruth; Nowicke, Carole E.; Jun, Mi Kung

    2010-01-01

    Survey responses by nonexperimental drug users in grades 6-12 were examined to determine whether MA users and nonusers with shared individual characteristics experience differential rates of police trouble, and whether specific factors place some users at greater risk than others. Findings showed that police trouble is pronounced for MA users,…

  14. Attempts to stop or reduce daily cannabis use: An intensive natural history study.

    PubMed

    Hughes, John R; Naud, Shelly; Budney, Alan J; Fingar, James R; Callas, Peter W

    2016-05-01

    We attempted to replicate and add to our prior study of attempts to stop or reduce cannabis use among daily cannabis users trying to change on their own, by observing a larger sample and adding further clinically relevant outcomes. Daily users (n = 193) who intended to stop or reduce sometime in the next 3 months called an Interactive Voice Response system each morning for 3 months to report on cannabis use, attempts to stop or reduce, withdrawal symptoms, and so forth, on the prior day. This study replicated our prior findings that (a) cannabis users trying to change make many, and often rapid, transitions among use as usual, reduction, and abstinence; (b) reduction attempts are more common than abstinence attempts; (c) quit and reduction attempts are short-lived and few participants achieve long-term abstinence; (d) alcohol and drug use are not greater on abstinence days; and (e) few users seek treatment. Novel findings included (f) a greater number of days of abstinence or intentional reduction predicted a greater decline in cannabis dependence, (g) most users do not prepare before their quit attempt, (h) coping outcomes during abstinence predict increased duration of abstinence, (i) tobacco use is less common on days of abstinence, and (j) withdrawal symptoms occur even with short quit attempts. Replication tests in more generalizable samples and of longer duration are indicated. Further natural history studies are likely to provide information to help improve the content of psychological treatments for cannabis use. (PsycINFO Database Record

  15. Attempts to Stop or Reduce Daily Cannabis Use: An Intensive Natural History Study

    PubMed Central

    Hughes, John R.; Naud, Shelly; Budney, Alan J.; Fingar, James R.; Callas, Peter W.

    2015-01-01

    We attempted to replicate and add to our prior study of attempts to stop or reduce cannabis use among daily cannabis users trying to change on their own, by observing a larger sample and adding further clinically-relevant outcomes. Daily users (n = 193) who intended to stop or reduce sometime in the next 3 months called an Interactive Voice Response system each morning for 3 months to report on cannabis use, attempts to stop or reduce, withdrawal symptoms, etc., on the prior day. This study replicated our prior findings that a) cannabis users trying to change make many, and often rapid, transitions among use as usual, reduction and abstinence; b) reduction attempts are more common than abstinence attempts; c) quit and reduction attempts are short-lived and few participants achieve long-term abstinence; d) alcohol and drug use are not greater on abstinence days; and e) few users seek treatment. Novel findings included f) a greater number of days of abstinence or intentional reduction predicted a greater decline in cannabis dependence; g) most users do not prepare before their quit attempt; h) coping outcomes during abstinence predict increased duration of abstinence; i) tobacco use is less common on days of abstinence; and j) withdrawal symptoms occur even with short quit attempts. Replication tests in more generalizable samples and of longer duration are indicated. Further natural history studies are likely to provide information to help improve the content of psychological treatments for cannabis use. PMID:26828641

  16. Attempts to stop or reduce daily cannabis use: An intensive natural history study.

    PubMed

    Hughes, John R; Naud, Shelly; Budney, Alan J; Fingar, James R; Callas, Peter W

    2016-05-01

    We attempted to replicate and add to our prior study of attempts to stop or reduce cannabis use among daily cannabis users trying to change on their own, by observing a larger sample and adding further clinically relevant outcomes. Daily users (n = 193) who intended to stop or reduce sometime in the next 3 months called an Interactive Voice Response system each morning for 3 months to report on cannabis use, attempts to stop or reduce, withdrawal symptoms, and so forth, on the prior day. This study replicated our prior findings that (a) cannabis users trying to change make many, and often rapid, transitions among use as usual, reduction, and abstinence; (b) reduction attempts are more common than abstinence attempts; (c) quit and reduction attempts are short-lived and few participants achieve long-term abstinence; (d) alcohol and drug use are not greater on abstinence days; and (e) few users seek treatment. Novel findings included (f) a greater number of days of abstinence or intentional reduction predicted a greater decline in cannabis dependence, (g) most users do not prepare before their quit attempt, (h) coping outcomes during abstinence predict increased duration of abstinence, (i) tobacco use is less common on days of abstinence, and (j) withdrawal symptoms occur even with short quit attempts. Replication tests in more generalizable samples and of longer duration are indicated. Further natural history studies are likely to provide information to help improve the content of psychological treatments for cannabis use. (PsycINFO Database Record PMID:26828641

  17. Therapeutic satisfaction and subjective effects of different strains of pharmaceutical-grade cannabis.

    PubMed

    Brunt, Tibor M; van Genugten, Marianne; Höner-Snoeken, Kathrin; van de Velde, Marco J; Niesink, Raymond J M

    2014-06-01

    In The Netherlands, pharmaceutical-grade cultivated cannabis is distributed for medicinal purposes as commissioned by the Ministry of Health. Few studies have thus far described its therapeutic efficacy or subjective (adverse) effects in patients. The aims of this study are to assess the therapeutic satisfaction within a group of patients using prescribed pharmaceutical-grade cannabis and to compare the subjective effects among the available strains with special focus on their delta-9-tetrahydrocannabinol and cannabidiol content. In a cross-sectional and natural design, users of pharmaceutical-grade cannabis were investigated with questionnaires. Medical background of the patients was asked as well as experienced therapeutic effects and characteristics of cannabis use. Subjective effects were measured with psychometric scales and used to compare among the strains of cannabis used across this group of patients. One hundred two patients were included; their average age was 53 years and 76% used it for more than a year preceding this study. Chronic pain (53%; n = 54) was the most common medical indication for using cannabis followed by multiple sclerosis (23%; n = 23), and 86% (n = 88) of patients (almost) always experienced therapeutic satisfaction when using pharmaceutical cannabis. Dejection, anxiety, and appetite stimulation were found to differ among the 3 strains of cannabis. These results show that patients report therapeutic satisfaction with pharmaceutical cannabis, mainly pain alleviation. Some subjective effects were found to differ among the available strains of cannabis, which is discussed in relation to their different tetrahydrocannabinol/cannabidiol content. These results may aid in further research and critical appraisal for medicinally prescribed cannabis products.

  18. Pharmacotherapies for cannabis dependence

    PubMed Central

    Marshall, Kushani; Gowing, Linda; Ali, Robert; Le Foll, Bernard

    2015-01-01

    Background Cannabis is the most prevalent illicit drug in the world. Demand for treatment of cannabis use disorders is increasing. There are currently no pharmacotherapies approved for treatment of cannabis use disorders. Objectives To assess the effectiveness and safety of pharmacotherapies as compared with each other, placebo or supportive care for reducing symptoms of cannabis withdrawal and promoting cessation or reduction of cannabis use. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (to 4 March 2014), MEDLINE (to week 3 February 2014), EMBASE (to 3 March 2014) and PsycINFO (to week 4 February 2014). We also searched reference lists of articles, electronic sources of ongoing trials and conference proceedings, and contacted selected researchers active in the area. Selection criteria Randomised and quasi-randomised controlled trials involving the use of medications to reduce the symptoms and signs of cannabis withdrawal or to promote cessation or reduction of cannabis use, or both, in comparison with other medications, placebo or no medication (supportive care) in participants diagnosed as cannabis dependent or who were likely to be dependent. Data collection and analysis We used standard methodological procedures expected by The Cochrane Collaboration. Two review authors assessed studies for inclusion and extracted data. All review authors confirmed the inclusion decisions and the overall process. Main results We included 14 randomised controlled trials involving 958 participants. For 10 studies the average age was 33 years; two studies targeted young people; and age data were not available for two studies. Approximately 80% of study participants were male. The studies were at low risk of selection, performance, detection and selective outcome reporting bias. Three studies were at risk of attrition bias. All studies involved comparison of active medication and placebo. The medications included preparations containing

  19. Motivational Enhancement Therapy for Adolescent Marijuana Users: A Preliminary Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Walker, Denise D.; Roffman, Roger A.; Stephens, Robert S.; Wakana, Kim; Berghuis, James

    2006-01-01

    This study's aims were (a) to investigate the feasibility of a school-based motivational enhancement therapy (MET) intervention in voluntarily attracting adolescents who smoke marijuana regularly but who are not seeking formal treatment and (b) to evaluate the efficacy of the intervention in reducing marijuana use. Ninety-seven adolescents who had…

  20. Surrender To Win: How Adolescent Drug and Alcohol Users Change Their Lives.

    ERIC Educational Resources Information Center

    Vaughn, Courtney; Long, Wesley

    1999-01-01

    Investigates the uniqueness and complexity of adolescent drug and alcohol abuse recovery, particularly the early years and events catalyzing the surrender process. Offers individual interviews of seven adolescents who surrendered their alcohol and drug addictions and constructed sober identities through participation in Alcoholics Anonymous. (GCP)

  1. Are Adolescent Substance Users Less Satisfied with Life as Young Adults and if so, Why?

    ERIC Educational Resources Information Center

    Bogart, Laura M.; Collins, Rebecca L.; Ellickson, Phyllis L.; Klein, David J.

    2007-01-01

    The present study investigated whether adolescent cigarette, alcohol, marijuana, and hard drug use predicts life satisfaction in young adulthood. Survey data were used from a longitudinal cohort of 2376 adolescents at ages 18 and 29, originally recruited from California and Oregon middle schools at age 13. Results of multivariate models indicated…

  2. The association between regular cannabis exposure and alterations of human brain morphology: an updated review of the literature.

    PubMed

    Lorenzetti, Valentina; Solowij, Nadia; Fornito, Alex; Lubman, Dan Ian; Yucel, Murat

    2014-01-01

    Cannabis is the most widely used illicit drug worldwide, though it is unclear whether its regular use is associated with persistent alterations in brain morphology. This review examines evidence from human structural neuroimaging investigations of regular cannabis users and focuses on achieving three main objectives. These include examining whether the literature to date provides evidence that alteration of brain morphology in regular cannabis users: i) is apparent, compared to non-cannabis using controls; ii) is associated with patterns of cannabis use; and with iii) measures of psychopathology and neurocognitive performance. The published findings indicate that regular cannabis use is associated with alterations in medial temporal, frontal and cerebellar brain regions. Greater brain morphological alterations were evident among samples that used at higher doses for longer periods. However, the evidence for an association between brain morphology and cannabis use parameters was mixed. Further, there is poor evidence for an association between measures of brain morphology and of psychopathology symptoms/neurocognitive performance. Overall, numerous methodological issues characterize the literature to date. These include investigation of small sample sizes, heterogeneity across studies in sample characteristics (e.g., sex, comorbidity) and in employed imaging techniques, as well as the examination of only a limited number of brain regions. These factors make it difficult to draw firm conclusions from the existing findings. Nevertheless, this review supports the notion that regular cannabis use is associated with alterations of brain morphology, and highlights the need to consider particular methodological issues when planning future cannabis research.

  3. Defining the Boundaries of Early Adolescence: A User's Guide to Assessing Pubertal Status and Pubertal Timing in Research with Adolescents

    ERIC Educational Resources Information Center

    Dorn, Lorah D.; Dahl, Ronald E.; Woodward, Hermi Rojahn; Biro, Frank

    2006-01-01

    This article addresses pragmatic issues regarding the assessment of puberty in research on adolescent health and development. Because pubertal processes have a major effect on physical, psychological, and social development, we posit that the assessment of pubertal status is at least as important as the specification of age for characterizing…

  4. Smoked Cannabis' Psychomotor and Neurocognitive Effects in Occasional and Frequent Smokers

    PubMed Central

    Desrosiers, Nathalie A.; Ramaekers, Johannes G.; Chauchard, Emeline; Gorelick, David A.; Huestis, Marilyn A.

    2015-01-01

    Δ9-Tetrahydrocannabinol (THC), the primary psychoactive constituent in cannabis, impairs psychomotor performance, cognition and driving ability; thus, driving under the influence of cannabis is a public safety concern. We documented cannabis' psychomotor, neurocognitive, subjective and physiological effects in occasional and frequent smokers to investigate potential differences between these smokers. Fourteen frequent (≥4x/week) and 11 occasional (<2x/week) cannabis smokers entered a secure research unit ∼19 h prior to smoking one 6.8% THC cigarette. Cognitive and psychomotor performance was evaluated with the critical tracking (CTT), divided attention (DAT), n-back (working memory) and Balloon Analog Risk (BART) (risk-taking) tasks at −1.75, 1.5, 3.5, 5.5 and 22.5 h after starting smoking. GLM (General Linear Model) repeated measures ANOVA was utilized to compare scores. Occasional smokers had significantly more difficulty compensating for CTT tracking error compared with frequent smokers 1.5 h after smoking. Divided attention performance declined significantly especially in occasional smokers, with session × group effects for tracking error, hits, false alarms and reaction time. Cannabis smoking did not elicit session × group effects on the n-back or BART. Controlled cannabis smoking impaired psychomotor function, more so in occasional smokers, suggesting some tolerance to psychomotor impairment in frequent users. These data have implications for cannabis-associated impairment in driving under the influence of cannabis cases. PMID:25745105

  5. Smoked cannabis' psychomotor and neurocognitive effects in occasional and frequent smokers.

    PubMed

    Desrosiers, Nathalie A; Ramaekers, Johannes G; Chauchard, Emeline; Gorelick, David A; Huestis, Marilyn A

    2015-05-01

    Δ9-Tetrahydrocannabinol (THC), the primary psychoactive constituent in cannabis, impairs psychomotor performance, cognition and driving ability; thus, driving under the influence of cannabis is a public safety concern. We documented cannabis' psychomotor, neurocognitive, subjective and physiological effects in occasional and frequent smokers to investigate potential differences between these smokers. Fourteen frequent (≥4x/week) and 11 occasional (<2x/week) cannabis smokers entered a secure research unit ∼19 h prior to smoking one 6.8% THC cigarette. Cognitive and psychomotor performance was evaluated with the critical tracking (CTT), divided attention (DAT), n-back (working memory) and Balloon Analog Risk (BART) (risk-taking) tasks at -1.75, 1.5, 3.5, 5.5 and 22.5 h after starting smoking. GLM (General Linear Model) repeated measures ANOVA was utilized to compare scores. Occasional smokers had significantly more difficulty compensating for CTT tracking error compared with frequent smokers 1.5 h after smoking. Divided attention performance declined significantly especially in occasional smokers, with session × group effects for tracking error, hits, false alarms and reaction time. Cannabis smoking did not elicit session × group effects on the n-back or BART. Controlled cannabis smoking impaired psychomotor function, more so in occasional smokers, suggesting some tolerance to psychomotor impairment in frequent users. These data have implications for cannabis-associated impairment in driving under the influence of cannabis cases. PMID:25745105

  6. Cannabis, the pregnant woman and her child: weeding out the myths.

    PubMed

    Jaques, S C; Kingsbury, A; Henshcke, P; Chomchai, C; Clews, S; Falconer, J; Abdel-Latif, M E; Feller, J M; Oei, J L

    2014-06-01

    To review and summarise the literature reporting on cannabis use within western communities with specific reference to patterns of use, the pharmacology of its major psychoactive compounds, including placental and fetal transfer, and the impact of maternal cannabis use on pregnancy, the newborn infant and the developing child. Review of published articles, governmental guidelines and data and book chapters. Although cannabis is one of the most widely used illegal drugs, there is limited data about the prevalence of cannabis use in pregnant women, and it is likely that reported rates of exposure are significantly underestimated. With much of the available literature focusing on the impact of other illicit drugs such as opioids and stimulants, the effects of cannabis use in pregnancy on the developing fetus remain uncertain. Current evidence indicates that cannabis use both during pregnancy and lactation, may adversely affect neurodevelopment, especially during periods of critical brain growth both in the developing fetal brain and during adolescent maturation, with impacts on neuropsychiatric, behavioural and executive functioning. These reported effects may influence future adult productivity and lifetime outcomes. Despite the widespread use of cannabis by young women, there is limited information available about the impact perinatal cannabis use on the developing fetus and child, particularly the effects of cannabis use while breast feeding. Women who are using cannabis while pregnant and breast feeding should be advised of what is known about the potential adverse effects on fetal growth and development and encouraged to either stop using or decrease their use. Long-term follow-up of exposed children is crucial as neurocognitive and behavioural problems may benefit from early intervention aimed to reduce future problems such as delinquency, depression and substance use.

  7. Cannabis, the pregnant woman and her child: weeding out the myths.

    PubMed

    Jaques, S C; Kingsbury, A; Henshcke, P; Chomchai, C; Clews, S; Falconer, J; Abdel-Latif, M E; Feller, J M; Oei, J L

    2014-06-01

    To review and summarise the literature reporting on cannabis use within western communities with specific reference to patterns of use, the pharmacology of its major psychoactive compounds, including placental and fetal transfer, and the impact of maternal cannabis use on pregnancy, the newborn infant and the developing child. Review of published articles, governmental guidelines and data and book chapters. Although cannabis is one of the most widely used illegal drugs, there is limited data about the prevalence of cannabis use in pregnant women, and it is likely that reported rates of exposure are significantly underestimated. With much of the available literature focusing on the impact of other illicit drugs such as opioids and stimulants, the effects of cannabis use in pregnancy on the developing fetus remain uncertain. Current evidence indicates that cannabis use both during pregnancy and lactation, may adversely affect neurodevelopment, especially during periods of critical brain growth both in the developing fetal brain and during adolescent maturation, with impacts on neuropsychiatric, behavioural and executive functioning. These reported effects may influence future adult productivity and lifetime outcomes. Despite the widespread use of cannabis by young women, there is limited information available about the impact perinatal cannabis use on the developing fetus and child, particularly the effects of cannabis use while breast feeding. Women who are using cannabis while pregnant and breast feeding should be advised of what is known about the potential adverse effects on fetal growth and development and encouraged to either stop using or decrease their use. Long-term follow-up of exposed children is crucial as neurocognitive and behavioural problems may benefit from early intervention aimed to reduce future problems such as delinquency, depression and substance use. PMID:24457255

  8. MDMA, cannabis, and cocaine produce acute dissociative symptoms.

    PubMed

    van Heugten-Van der Kloet, Dalena; Giesbrecht, Timo; van Wel, Janelle; Bosker, Wendy M; Kuypers, Kim P C; Theunissen, Eef L; Spronk, Desirée B; Jan Verkes, Robbert; Merckelbach, Harald; Ramaekers, Johannes G

    2015-08-30

    Some drugs of abuse may produce dissociative symptoms, but this aspect has been understudied. We explored the dissociative potential of three recreational drugs (3,4-methylenedioxymethamphetamine (MDMA), cannabis, and cocaine) during intoxication and compared their effects to literature reports of dissociative states in various samples. Two placebo-controlled studies were conducted. In Study 1 (N=16), participants received single doses of 25, 50, and 100 mg of MDMA, and placebo. In Study 2 (N=21), cannabis (THC 300 µg/kg), cocaine (HCl 300 mg), and placebo were administered. Dissociative symptoms as measured with the Clinician-Administered Dissociative States Scale (CADSS) significantly increased under the influence of MDMA and cannabis. To a lesser extent, this was also true for cocaine. Dissociative symptoms following MDMA and cannabis largely exceeded those observed in schizophrenia patients, were comparable with those observed in Special Forces soldiers undergoing survival training, but were lower compared with ketamine-induced dissociation. Cocaine produced dissociative symptoms that were comparable with those observed in schizophrenia patients, but markedly less than those in Special Forces soldiers and ketamine users. Thus, MDMA and cannabis can produce dissociative symptoms that resemble dissociative pathology. The study of drug induced dissociation is important, because it may shed light on the mechanisms involved in dissociative psychopathology.

  9. MDMA, cannabis, and cocaine produce acute dissociative symptoms.

    PubMed

    van Heugten-Van der Kloet, Dalena; Giesbrecht, Timo; van Wel, Janelle; Bosker, Wendy M; Kuypers, Kim P C; Theunissen, Eef L; Spronk, Desirée B; Jan Verkes, Robbert; Merckelbach, Harald; Ramaekers, Johannes G

    2015-08-30

    Some drugs of abuse may produce dissociative symptoms, but this aspect has been understudied. We explored the dissociative potential of three recreational drugs (3,4-methylenedioxymethamphetamine (MDMA), cannabis, and cocaine) during intoxication and compared their effects to literature reports of dissociative states in various samples. Two placebo-controlled studies were conducted. In Study 1 (N=16), participants received single doses of 25, 50, and 100 mg of MDMA, and placebo. In Study 2 (N=21), cannabis (THC 300 µg/kg), cocaine (HCl 300 mg), and placebo were administered. Dissociative symptoms as measured with the Clinician-Administered Dissociative States Scale (CADSS) significantly increased under the influence of MDMA and cannabis. To a lesser extent, this was also true for cocaine. Dissociative symptoms following MDMA and cannabis largely exceeded those observed in schizophrenia patients, were comparable with those observed in Special Forces soldiers undergoing survival training, but were lower compared with ketamine-induced dissociation. Cocaine produced dissociative symptoms that were comparable with those observed in schizophrenia patients, but markedly less than those in Special Forces soldiers and ketamine users. Thus, MDMA and cannabis can produce dissociative symptoms that resemble dissociative pathology. The study of drug induced dissociation is important, because it may shed light on the mechanisms involved in dissociative psychopathology. PMID:26003508

  10. Mobile App-Delivered Cognitive Behavioral Therapy for Insomnia: Feasibility and Initial Efficacy Among Veterans With Cannabis Use Disorders

    PubMed Central

    2015-01-01

    Background Cannabis is the most frequently used illicit substance in the United States resulting in high rates of cannabis use disorders. Current treatments for cannabis use are often met with high rates of lapse/relapse, tied to (1) behavioral health factors that impact cannabis use such as poor sleep, and (2) access, stigma, supply, and cost of receiving a substance use intervention. Objective This pilot study examined the feasibility, usability, and changes in cannabis use and sleep difficulties following mobile phone–delivered Cognitive Behavioral Therapy for Insomnia (CBT-I) in the context of a cannabis cessation attempt. Methods Four male veterans with DSM-5 cannabis use disorder and sleep problems were randomized to receive a 2-week intervention: CBT-I Coach mobile app (n=2) or a placebo control (mood-tracking app) (n=2). Cannabis and sleep measures were assessed pre- and post-treatment. Participants also reported use and helpfulness of each app. Changes in sleep and cannabis use were evaluated for each participant individually. Results Both participants receiving CBT-I used the app daily over 2 weeks and found the app user-friendly, helpful, and would use it in the future. In addition, they reported decreased cannabis use and improved sleep efficiency; one also reported increased sleep quality. In contrast, one participant in the control group dropped out of the study, and the other used the app minimally and reported increased sleep quality but also increased cannabis use. The mood app was rated as not helpful, and there was low likelihood of future participation. Conclusions This pilot study examined the feasibility and initial patient acceptance of mobile phone delivery of CBT-I for cannabis dependence. Positive ratings of the app and preliminary reports of reductions in cannabis use and improvements in sleep are both encouraging and support additional evaluation of this intervention. PMID:26187404

  11. Evidence for Shared Predisposition in the Relationship between Cannabis Use and Subcortical Brain Structure

    PubMed Central

    Pagliaccio, David; Barch, Deanna M.; Bogdan, Ryan; Wood, Phillip K.; Lynskey, Michael T.; Heath, Andrew C.; Agrawal, Arpana

    2015-01-01

    the exposed and unexposed siblings in pairs discordant for cannabis exposure showed reduced amygdala volumes relative to members of concordant unexposed pairs. Conclusions and Relevance Differences in amygdala volume in cannabis users are attributable to common predispositional factors, genetic or environmental in origin, with little support for causal influences. Causal influences, in isolation or in conjunction with predispositional factors, may exist for other brain regions (e.g. ventral striatum) or at more severe levels of cannabis involvement and deserve further study. PMID:26308883

  12. Preparation and Distribution of Cannabis and Cannabis-Derived Dosage Formulations for Investigational and Therapeutic Use in the United States.

    PubMed

    Thomas, Brian F; Pollard, Gerald T

    2016-01-01

    Cannabis is classified as a schedule I controlled substance by the US Drug Enforcement Agency, meaning that it has no medicinal value. Production is legally restricted to a single supplier at the University of Mississippi, and distribution to researchers is tightly controlled. However, a majority of the population is estimated to believe that cannabis has legitimate medical or recreational value, numerous states have legalized or decriminalized possession to some degree, and the federal government does not strictly enforce its law and is considering rescheduling. The explosive increase in open sale and use of herbal cannabis and its products has occurred with widely variable and in many cases grossly inadequate quality control at all levels-growing, processing, storage, distribution, and use. This paper discusses elements of the analytical and regulatory system that need to be put in place to ensure standardization for the researcher and to reduce the hazards of contamination, overdosing, and underdosing for the end-user. PMID:27630566

  13. Preparation and Distribution of Cannabis and Cannabis-Derived Dosage Formulations for Investigational and Therapeutic Use in the United States

    PubMed Central

    Thomas, Brian F.; Pollard, Gerald T.

    2016-01-01

    Cannabis is classified as a schedule I controlled substance by the US Drug Enforcement Agency, meaning that it has no medicinal value. Production is legally restricted to a single supplier at the University of Mississippi, and distribution to researchers is tightly controlled. However, a majority of the population is estimated to believe that cannabis has legitimate medical or recreational value, numerous states have legalized or decriminalized possession to some degree, and the federal government does not strictly enforce its law and is considering rescheduling. The explosive increase in open sale and use of herbal cannabis and its products has occurred with widely variable and in many cases grossly inadequate quality control at all levels—growing, processing, storage, distribution, and use. This paper discusses elements of the analytical and regulatory system that need to be put in place to ensure standardization for the researcher and to reduce the hazards of contamination, overdosing, and underdosing for the end-user.

  14. Preparation and Distribution of Cannabis and Cannabis-Derived Dosage Formulations for Investigational and Therapeutic Use in the United States

    PubMed Central

    Thomas, Brian F.; Pollard, Gerald T.

    2016-01-01

    Cannabis is classified as a schedule I controlled substance by the US Drug Enforcement Agency, meaning that it has no medicinal value. Production is legally restricted to a single supplier at the University of Mississippi, and distribution to researchers is tightly controlled. However, a majority of the population is estimated to believe that cannabis has legitimate medical or recreational value, numerous states have legalized or decriminalized possession to some degree, and the federal government does not strictly enforce its law and is considering rescheduling. The explosive increase in open sale and use of herbal cannabis and its products has occurred with widely variable and in many cases grossly inadequate quality control at all levels—growing, processing, storage, distribution, and use. This paper discusses elements of the analytical and regulatory system that need to be put in place to ensure standardization for the researcher and to reduce the hazards of contamination, overdosing, and underdosing for the end-user. PMID:27630566

  15. Preparation and Distribution of Cannabis and Cannabis-Derived Dosage Formulations for Investigational and Therapeutic Use in the United States.

    PubMed

    Thomas, Brian F; Pollard, Gerald T

    2016-01-01

    Cannabis is classified as a schedule I controlled substance by the US Drug Enforcement Agency, meaning that it has no medicinal value. Production is legally restricted to a single supplier at the University of Mississippi, and distribution to researchers is tightly controlled. However, a majority of the population is estimated to believe that cannabis has legitimate medical or recreational value, numerous states have legalized or decriminalized possession to some degree, and the federal government does not strictly enforce its law and is considering rescheduling. The explosive increase in open sale and use of herbal cannabis and its products has occurred with widely variable and in many cases grossly inadequate quality control at all levels-growing, processing, storage, distribution, and use. This paper discusses elements of the analytical and regulatory system that need to be put in place to ensure standardization for the researcher and to reduce the hazards of contamination, overdosing, and underdosing for the end-user.

  16. [Cannabis smoking and lung cancer].

    PubMed

    Underner, M; Urban, T; Perriot, J; de Chazeron, I; Meurice, J-C

    2014-06-01

    Cannabis is the most commonly smoked illicit substance in the world. It can be smoked alone in plant form (marijuana) but it is mainly smoked mixed with tobacco. The combined smoking of cannabis and tobacco is a common-place phenomenon in our society. However, its use is responsible for severe pulmonary consequences. The specific impact of smoking cannabis is difficult to assess precisely and to distinguish from the effect of tobacco. Marijuana smoke contains polycyclic aromatic hydrocarbons and carcinogens at higher concentration than tobacco smoke. Cellular, tissue, animal and human studies, and also epidemiological studies, show that marijuana smoke is a risk factor for lung cancer. Cannabis exposure doubles the risk of developing lung cancer. This should encourage clinicians to identify cannabis use and to offer patients support in quitting.

  17. Chest pain, troponin rise, and ST-elevation in an adolescent boy following the use of the synthetic cannabis product K2

    PubMed Central

    Zaleta, Sona; Kumar, Prashant; Miller, Sarah

    2016-01-01

    “Legal highs” such as K2, which typically contain synthetic cannabinoids, are increasingly popular with adolescents around the world. We have limited knowledge concerning their toxicity or adverse effects and their mechanism of action is poorly understood. While synthetic cannabinoids have been linked to adverse cardiovascular effects, cases of ST-elevation myocardial infarction (STEMI) associated with K2 use are exceedingly rare. We report a case of a 14-year-old boy who suffered an STEMI after smoking K2. To our knowledge, this is not only the youngest case of an STEMI associated with K2 use, but also the first case to be reported outside of the United States of America. Pediatricians worldwide must be aware of the clinical significance and potential harm associated with the use of synthetic cannabinoids, to better educate patients and their families regarding the dangers of using such “legal” substances. PMID:27011700

  18. Smoking tobacco along with marijuana increases symptoms of cannabis dependence

    PubMed Central

    Ream, Geoffrey L.; Benoit, Ellen; Johnson, Bruce D.; Dunlap, Eloise

    2008-01-01

    Aim User practices/rituals that involve concurrent use of tobacco and marijuana – smoking blunts and “chasing” marijuana with tobacco – are hypothesized to increase cannabis dependence symptoms. Design Ethnographers administered group surveys to a diverse, purposive sample of marijuana users who appeared to be 17–35 years old. Setting New York City, including non-impoverished areas of Manhattan, the transitional area of East Village/Lower East Side, low-income areas of northern Manhattan and South Bronx, and diverse areas of Brooklyn and Queens. Participants 481 marijuana users ages 14–35, 57% male, 43% female; 27% White, 30% Black, 19% Latino, 5% Asian, 20% of other/multiple race. Measurements Among many other topics, group surveys measured cannabis dependence symptoms; frequencies of chasing, blunt smoking, joint/pipe smoking, using marijuana while alone, and general tobacco use; and demographic factors. Findings Blunt smoking and chasing marijuana with tobacco were each uniquely associated with five of the seven cannabis dependence symptoms. Across symptoms, predicted odds were 2.4–4.1 times greater for participants who smoked blunts on all 30 of the past 30 days than for participants who did not smoke blunts in the past 30 days. Significant increases in odds over the whole range of the five-point chasing frequency measure (from never to always) ranged from 3.4 times to 5.1 times. Conclusions Using tobacco with marijuana – smoking blunts and “chasing” marijuana with tobacco – contributes to cannabis dependence symptoms. Treatment for cannabis dependence may be more effective it addresses the issue of concurrent tobacco use. PMID:18339491

  19. Cannabis-related hospitalizations: unexpected serious events identified through hospital databases

    PubMed Central

    Jouanjus, Emilie; Leymarie, Florence; Tubery, Marie; Lapeyre-Mestre, Maryse

    2011-01-01

    AIMS Cannabis is the most prevalent illicit drug used worldwide and can be responsible for serious health defects in users. However, the risk related to cannabis consumption is not well established. The present study aimed to assess cannabis-related adverse events leading to hospitalization, and to estimate the corresponding annual risk for consumers. METHODS Participants were patients admitted to the public hospitals in the Toulouse area (France) between January 2004 and December 2007 in relation to the use of cannabis. Reasons for admission and other occurring events were identified through hospital discharge summaries. We described all observed adverse events (AEs) and estimated their regional incidence on the basis of cannabis consumption data. RESULTS We included 200 patients, and identified a total of 619 adverse events (AEs), one of which was lethal. Psychiatric disorders involved 57.7% of patients and accounted for 18.2% of AEs. Most frequent outcomes were central and peripheral nervous system disorders (15.8% of AEs), acute intoxication (12.1%), respiratory system disorders (11.1%) and cardiovascular disorders (9.5%). We estimated that in 2007 the incidence of cannabis-related AEs in the Midi-Pyrenees region ranged from 1.2 per 1000 regular cannabis users (95% confidence interval (CI) 0.7, 1.6) to 3.2 (95% CI 2.5, 3.9). CONCLUSIONS Cannabis use is associated with complications, considered to be serious since they lead to hospitalization. Beyond the well-known and widely investigated psychiatric events, serious cerebro and cardiov