Altered subjective reward valuation among female heavy marijuana users.

PubMed

Hefner, Kathryn R; Starr, Mark J

2017-02-01

Maladaptive decision-making is a cardinal feature of drug use, contributing to ongoing use, and reflecting alterations in how drug users assess uncertain reward value. Accumulating evidence indicates the consequences of heavy marijuana use are worse for female versus male animals and humans, but research assessing sex differences in reward-related decision-making among marijuana users remains scarce. We examined sex differences in the subjective valuation of certain and uncertain rewards among heavy marijuana users (52; 26 male and 26 female) and controls (52; 26 male and 26 female). We offered male and female heavy marijuana users and controls monetary rewards of certain and uncertain (probabilistic) values. We measured how preferences for uncertain rewards varied by the objective value of those rewards, moderators of reward uncertainty, Marijuana Group and Sex. Men were more sensitive to changes in the objective value of uncertain rewards than women. However, this effect of Sex differed by Marijuana Group. Female heavy marijuana users were more sensitive to changes in uncertain reward value, particularly when the "stakes" were high (i.e., greater difference between potential uncertain rewards), than female controls. Female heavy marijuana users' sensitivity to changes in the value of high stakes uncertain rewards was comparable to male marijuana users and controls. In contrast, male marijuana users' sensitivity to changes in the value of high stakes uncertain rewards did not differ from male controls. These results suggest sex differences in sensitivity to high risk rewards may be one pathway contributing to severer consequences of heavy marijuana use among women. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Characterizing marijuana concentrate users: A web-based survey.

PubMed

Daniulaityte, Raminta; Lamy, Francois R; Barratt, Monica; Nahhas, Ramzi W; Martins, Silvia S; Boyer, Edward W; Sheth, Amit; Carlson, Robert G

2017-09-01

The study seeks to characterize marijuana concentrate users, describe reasons and patterns of use, perceived risk, and identify predictors of daily/near daily use. An anonymous web-based survey was conducted (April-June 2016) with 673 US-based cannabis users recruited via the Bluelight.org web-forum and included questions about marijuana concentrate use, other drugs, and socio-demographics. Multivariable logistic regression analyses were conducted to identify characteristics associated with greater odds of lifetime and daily use of marijuana concentrates. About 66% of respondents reported marijuana concentrate use. The sample was 76% male, and 87% white. Marijuana concentrate use was viewed as riskier than flower cannabis. Greater odds of marijuana concentrate use was associated with living in states with "recreational" (AOR=4.91; p=0.001) or "medical, less restrictive" marijuana policies (AOR=1.87; p=0.014), being male (AOR=2.21, p=0.002), younger (AOR=0.95, p<0.001), number of other drugs used (AOR=1.23, p<0.001), daily herbal cannabis use (AOR=4.28, p<0.001), and lower perceived risk of cannabis use (AOR=0.96, p=0.043). About 13% of marijuana concentrate users reported daily/near daily use. Greater odds of daily concentrate use was associated with being male (AOR=9.29, p=0.033), using concentrates for therapeutic purposes (AOR=7.61, p=0.001), using vape pens for marijuana concentrate administration (AOR=4.58, p=0.007), and lower perceived risk of marijuana concentrate use (AOR=0.92, p=0.017). Marijuana concentrate use was more common among male, younger and more experienced users, and those living in states with more liberal marijuana policies. Characteristics of daily users, in particular patterns of therapeutic use and utilization of different vaporization devices, warrant further research with community-recruited samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Rules regarding marijuana and its use in personal residences: findings from marijuana users and nonusers recruited through social media.

PubMed

Berg, Carla J; Buller, David B; Schauer, Gillian L; Windle, Michael; Stratton, Erin; Kegler, Michelle C

2015-01-01

Recent changes in policy and social norms related to marijuana use have increased its use and concern about how/where marijuana should be used. We aimed to characterize rules regarding marijuana and its use in homes. We recruited 1,567 US adults aged 18-34 years through Facebook advertisements to complete an online survey assessing marijuana use, social factors, perceptions of marijuana, and rules regarding marijuana and its use in the home, targeting tobacco and marijuana users to ensure the relevance of this topic. Overall, 648 (41.6%) were current marijuana users; 46.0% of participants reported that "marijuana of any type is not allowed in their home or on their property." Of those allowing marijuana on their property, 6.4% prohibited use of marijuana in their home. Of the remainder, 29.2% prohibited smoking marijuana, and 11.0% prohibited vaping, eating, or drinking marijuana. Correlates of more restrictive rules included younger age, being female, having marijuana, perceiving use to be less socially acceptable and more harmful, and being a nonuser (p's <.05). Attitudes and subjective norms regarding marijuana are correlates of allowing marijuana in residential settings. Future work should examine areas of risk regarding household marijuana rules.

Altered subjective reward valuation among female heavy marijuana users

PubMed Central

Hefner, Kathryn R.; Starr, Mark. J.

2016-01-01

Maladaptive decision-making is a cardinal feature of drug use, contributing to ongoing use, and reflecting alterations in how drug users assess uncertain reward value. Accumulating evidence indicates the consequences of heavy marijuana use are worse for female versus male animals and humans, but research assessing sex differences in reward-related decision-making among marijuana users remains scarce. We examined sex differences in the subjective valuation of certain and uncertain rewards among heavy marijuana users (52; 26 male and 26 female) and controls (52; 26 male and 26 female). We offered male and female heavy marijuana users and controls monetary rewards of certain and uncertain (probabilistic) values. We measured how preferences for uncertain rewards varied by the objective value of those rewards, moderators of reward uncertainty, marijuana use, and sex. Men were more sensitive to changes in the objective value of uncertain rewards than women. However, this effect of sex differed by marijuana group. Female heavy marijuana users were more sensitive to changes in uncertain reward value, particularly when the ‘stakes’ were high (i.e., greater difference between potential uncertain rewards), than female controls. Female heavy marijuana users’ sensitivity to changes in the value of high stakes uncertain rewards was comparable to male marijuana users and controls. In contrast, male marijuana users’ sensitivity to changes in the value of high stakes uncertain rewards did not differ from male controls. These results suggest sex differences in sensitivity to high risk rewards may be one pathway contributing to severer consequences of heavy marijuana use among women. PMID:27936816

Sociopsychological Characteristics of Undergraduate Marijuana Users

ERIC Educational Resources Information Center

Cunningham, William H.; And Others

1974-01-01

Presents a study of 547 college students which found that: 1) It is possible to distinguish between undergraduate subjects who smoke marijuana and those who do not, 2) It is possible to draw a reasonable clear picture of the marijuana users' demographic characteristics, and 3) There is a positive relationship between the use of marijuana and the…

Psychometric evaluation of the Marijuana Reduction Strategies Self-Efficacy Scale with young recreational marijuana users.

PubMed

Davis, Alan K; Osborn, Lawrence A; Rosenberg, Harold; Cross, Nicole; Lauritsen, Kirstin J; Ashrafioun, Lisham; Bradbury, Stacey; Feuille, Margaret; Lackey, Jennifer H; Hawley, Anna; Leith, Jaclyn

2014-12-01

This study evaluated the cue-reactivity and several psychometric properties of a questionnaire designed to assess marijuana users' self-efficacy to employ 21 specific cognitive-behavioral strategies to reduce their marijuana use. Using a web-based recruitment and data-collection procedure, 513 regular marijuana users completed dependent measures following marijuana-related or control cue exposure. Although exposure to marijuana-related stimuli significantly increased reported craving, mean reduction-strategy self-efficacy scores did not differ as a function of cue exposure. Reliability analyses supported retaining all 21 items as a single scale. Reduction-strategy self-efficacy was positively associated with marijuana-refusal self-efficacy and with recent past use of reduction strategies, was negatively associated with quantity and frequency of marijuana use and marijuana-related problems, and was positively but weakly associated with general self-efficacy. The most frequently reported strategies that were employed reflected restricting marijuana use to once per day, not keeping a large stash available, turning down unwanted hits, and not obtaining more marijuana right away if one's supply runs out. These findings further support the reliability and validity of the questionnaire when administered to a diverse sample of regular marijuana users. Copyright © 2014 Elsevier Ltd. All rights reserved.

Daily marijuana users with past alcohol problems increase alcohol consumption during marijuana abstinence.

PubMed

Peters, Erica N; Hughes, John R

2010-01-15

Drug abuse treatment programs typically recommend complete abstinence because of a fear that clients who stop use of one drug will substitute another. A within-subjects study investigated whether consumption of alcohol and other substances changes during marijuana abstinence. Twenty-eight daily marijuana users who were not trying to stop or reduce their marijuana consumption completed an 8-day baseline period in which they used marijuana and other drugs as usual, a 13-day marijuana abstinence period, and a 7-day return-to-baseline period. Participants provided self-report of substance use daily and submitted urine samples twice weekly to verify marijuana abstinence. A diagnosis of past alcohol abuse or dependence significantly moderated the alcohol increase from baseline to marijuana abstinence (p<0.01), such that individuals with this diagnosis significantly increased alcohol use (52% increase) but those without this history did not (3% increase). Increases in marijuana withdrawal discomfort scores and alcohol craving scores from baseline to marijuana abstinence significantly and positively correlated with increases in alcohol use. Increases in cigarettes, caffeine, and non-marijuana illicit drugs did not occur. This study provides empirical validation of drug substitution in a subgroup of daily marijuana users, but results need to be replicated in individuals who seek treatment for marijuana problems. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

Emotion regulation deficits in regular marijuana users.

PubMed

Zimmermann, Kaeli; Walz, Christina; Derckx, Raissa T; Kendrick, Keith M; Weber, Bernd; Dore, Bruce; Ochsner, Kevin N; Hurlemann, René; Becker, Benjamin

2017-08-01

Effective regulation of negative affective states has been associated with mental health. Impaired regulation of negative affect represents a risk factor for dysfunctional coping mechanisms such as drug use and thus could contribute to the initiation and development of problematic substance use. This study investigated behavioral and neural indices of emotion regulation in regular marijuana users (n = 23) and demographically matched nonusing controls (n = 20) by means of an fMRI cognitive emotion regulation (reappraisal) paradigm. Relative to nonusing controls, marijuana users demonstrated increased neural activity in a bilateral frontal network comprising precentral, middle cingulate, and supplementary motor regions during reappraisal of negative affect (P < 0.05, FWE) and impaired emotion regulation success on the behavioral level (P < 0.05). Amygdala-focused analyses further revealed impaired amygdala downregulation in the context of decreased amygdala-dorsolateral prefrontal cortex functional connectivity (P < 0.05, FWE) during reappraisal in marijuana users relative to controls. Together, the present findings could reflect an unsuccessful attempt of compensatory recruitment of additional neural resources in the context of disrupted amygdala-prefrontal interaction during volitional emotion regulation in marijuana users. As such, impaired volitional regulation of negative affect might represent a consequence of, or risk factor for, regular marijuana use. Hum Brain Mapp 38:4270-4279, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Working Memory and Impulsivity Predict Marijuana-Related Problems Among Frequent Users

PubMed Central

Day, Anne M.; Metrik, Jane; Spillane, Nichea S.; Kahler, Christopher W.

2012-01-01

Background Although marijuana is the most commonly used illicit substance in the US, only a small portion of users go on to develop dependence, suggesting that there are substantial individual differences in vulnerability to marijuana-related problems among users. Deficits in working memory and high trait impulsivity are two factors that may place marijuana users at increased risk for experiencing related problems. Methods Using baseline data from an experimental study that recruited 104 frequent marijuana users (M=71.86% of prior 60 days, SD=22%), we examined the associations of working memory and trait impulsivity with marijuana-related problems. Results Lower working memory, as measured by Trail Making Test B, but not short-term memory capacity, predicted more marijuana-related problems. Higher trait impulsivity scores were independently associated with greater number of problems. Conclusions Results suggest that marijuana users with reduced executive cognitive ability are more susceptible to developing problems related to their use. Trait impulsivity and executive working memory appear to be independent risk factors for experiencing marijuana-related problems. PMID:23312340

Examining Marijuana User and Non-User Prototypes in Formative Research for Prevention Campaigns

ERIC Educational Resources Information Center

Comello, Maria Leonora G.; Slater, Michael D.

2010-01-01

We report on research--both quantitative and qualitative--conducted to explore perceptions of prototypes of marijuana users, as well as the extent to which self-prototype congruence predicted marijuana use intention. Results of a survey of undergraduates (N = 139) showed that prototypes of users and non-users differed in terms of key attributes,…

Stigma towards Marijuana Users and Heroin Users.

PubMed

Brown, Seth A

2015-01-01

Despite high levels of stigmatizing attitudes and behaviors toward individuals with substance use problems, there is surprisingly limited research on understanding the contributors to such high levels. College students with no history of marijuana or heroin use (N=250) completed self-report measures to examine the level of substance use stigma towards individuals using two illicit substances (marijuana and heroin) and the contribution of three perceiver characteristics (sex, previous contact with substance users, and five beliefs about substance use) to three dimensions of stigma (social distance, negative emotions, and forcing treatment). Greater levels of internalized stigma were noted towards individuals who use heroin (versus marijuana). For marijuana use, those who had less previous contact and higher endorsement of certain beliefs (rarity, severity, and less controllability) were associated with greater stigmatizing attitudes. For heroin use, the associations were weak or non-existent. The findings strengthen the argument that substance use stigma needs to be examined and perhaps addressed substance by substance, rather than as a group. Further, contact interventions may be a particularly effective strategy for altering substance use stigma.

Spatial Working Memory Performance and fMRI Activation Interactions in Abstinent Adolescent Marijuana Users

PubMed Central

Padula, Claudia B.; Schweinsburg, Alecia D.; Tapert, Susan F.

2008-01-01

Previous studies have suggested neural disruption and reorganization in adult marijuana users. However, it remains unclear whether these effects persist in adolescents after 28 days of abstinence and, if they do, what Performance × Brain Response interactions occur. Adolescent marijuana users (n = 17) and controls (n = 17) aged 16–18 years were recruited from local schools. Functional magnetic resonance imaging data were collected after 28 days’ monitored abstinence as participants performed a spatial working memory task. Marijuana users show Performance × Brain Response interactions in the bilateral temporal lobes, left anterior cingulate, left parahippocampal gyrus, and right thalamus (clusters ≥ 1358 μl; p <.05), although groups do not differ on behavioral measures of task performance. Marijuana users show differences in brain response to a spatial working memory task despite adequate performance, suggesting a different approach to the task via altered neural pathways. PMID:18072830

One-year prospective prediction of marijuana use cessation among youth at continuation high schools.

PubMed

Sussman, S; Dent, C W

1999-01-01

This article reports a large-scale study of the prediction of marijuana use cessation among adolescents who were regular users at baseline. Social, attitude, intrapersonal, violence-related, drug-use-related, and demographic baseline measures served as predictors of whether or not 566 current marijuana users reported having quit use 1 year later. Quitting was defined as having not used marijuana in the last 30 days and having no intention to use marijuana in the future (31% of the baseline users). Those who were slightly older, who reported receiving relatively less approval for using drugs, who held relatively unfavorable attitudes about the acceptability of drug use, and who reported relatively less victimization in the last year were relatively likely to quit. Implications of these results include the need to increase unacceptability of marijuana use to help increase efforts at self-initiated quitting.

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. Published by Elsevier Ltd.

Altered Neural Processing to Social Exclusion in Young Adult Marijuana Users

PubMed Central

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

2015-01-01

Previous studies have reported that peer groups are one of the most important predictors of adolescent and young adult marijuana use, and yet the neural correlates of social processing in marijuana users have not yet been studied. In the current study, marijuana-using young adults (n = 20) and non-using controls (n = 22) participated in a neuroimaging social exclusion task called Cyberball, a computerized ball-tossing game in which the participant is excluded from the game after a pre-determined number of ball tosses. Controls, but not marijuana users, demonstrated significant activation in the insula, a region associated with negative emotion, when being excluded from the game. Both groups demonstrated activation of the ventral anterior cingulate cortex (vACC), a region associated with affective monitoring, during peer exclusion. Only the marijuana group showed a correlation between vACC activation and scores on a self-report measure of peer conformity. This study indicates that marijuana users show atypical neural processing of social exclusion, which may be either caused by, or the result of, regular marijuana use. PMID:26977454

Functional MRI of inhibitory processing in abstinent adolescent marijuana users.

PubMed

Tapert, Susan F; Schweinsburg, Alecia D; Drummond, Sean P A; Paulus, Martin P; Brown, Sandra A; Yang, Tony T; Frank, Lawrence R

2007-10-01

Marijuana intoxication appears to impair response inhibition, but it is unclear if impaired inhibition and associated brain abnormalities persist after prolonged abstinence among adolescent users. We hypothesized that brain activation during a go/no-go task would show persistent abnormalities in adolescent marijuana users after 28 days of abstinence. Adolescents with (n = 16) and without (n = 17) histories of marijuana use were compared on blood oxygen level dependent (BOLD) response to a go/no-go task during functional magnetic resonance imaging (fMRI) after 28 days of monitored abstinence. Participants had no neurological problems or Axis I diagnoses other than cannabis abuse/dependence. Marijuana users did not differ from non-users on task performance but showed more BOLD response than non-users during inhibition trials in right dorsolateral prefrontal, bilateral medial frontal, bilateral inferior and superior parietal lobules, and right occipital gyri, as well as during "go" trials in right prefrontal, insular, and parietal cortices (p < 0.05, clusters > 943 microl). Differences remained significant even after controlling for lifetime and recent alcohol use. Adolescent marijuana users relative to non-users showed increased brain processing effort during an inhibition task in the presence of similar task performance, even after 28 days of abstinence. Thus, increased brain processing effort to achieve inhibition may predate the onset of regular use or result from it. Future investigations will need to determine whether increased brain processing effort is associated with risk to use.

Discriminability of Personality Profiles in Isolated and Co-Morbid Marijuana and Nicotine Users

PubMed Central

Ketcherside, Ariel; Jeon-Slaughter, Haekyung; Baine, Jessica L.; Filbey, Francesca M

2016-01-01

Specific personality traits have been linked with substance use disorders (SUDs), genetic mechanisms, and brain systems. Thus, determining the specificity of personality traits to types of SUD can advance the field towards defining SUD endophenotypes as well as understanding the brain systems involved for the development of novel treatments. Disentangling these factors is particularly important in highly co-morbid SUDs, such as marijuana and nicotine use, so treatment can occur effectively for both. This study evaluated personality traits that distinguish isolated and co-morbid use of marijuana and nicotine. To that end, we collected the NEO Five Factor Inventory in participants who used marijuana-only (n=59), nicotine-only (n=27), both marijuana and nicotine (n=28), and in non-using controls (n=28). We used factor analyses to identify personality profiles, which are linear combinations of the five NEO Factors. We then conducted Receiver Operating Characteristics (ROC) curve analysis to test accuracy of the personality factors in discriminating isolated and co-morbid marijuana and nicotine users from each other. ROC curve analysis distinguished the four groups based on their NEO personality patterns. Results showed that NEO Factor 2 (openness, extraversion, agreeableness) discriminated marijuana and marijuana + nicotine users from controls and nicotine-only users with high predictability. Additional ANOVA results showed that the openness dimension discriminated marijuana users from nicotine users. These findings suggest that personality dimensions distinguish marijuana users from nicotine users and should be considered in prevention strategies. PMID:27086256

Psychosocial and cessation-related differences between tobacco-marijuana co-users and single product users in a college student population.

PubMed

Masters, Matthew N; Haardörfer, Regine; Windle, Michael; Berg, Carla

2018-02-01

Limited research has examined psychosocial factors that differ among cigarette users, marijuana users, and co-users and influence their cessation efforts. We examined: 1) sociodemographic, mental health, and other substance use in relation to user category; and 2) associations among these factors in relation to recent quit attempts and readiness to quit among single product versus co-users. We used a cross-sectional design to study college students aged 18-25 from seven Georgia campuses, focusing on the 721 reporting cigarette and/or marijuana use in the past 4months (238 cigarette-only; 331 marijuana-only; 152 co-users). Multinomial logistic regression showed that correlates (p's<0.05) of cigarette-only versus co-use included attending public or technical colleges (vs. private) and not using little cigars/cigarillos (LCCs), e-cigarettes, and alcohol. Correlates of marijuana-only versus co-use included being Black or Hispanic (vs. White), not attending technical school, and not using LCCs and e-cigarettes. Importance was rated higher for quitting cigarettes versus marijuana, but confidence was rated lower for quitting cigarettes versus marijuana (p's<0.001). Co-users were more likely to report readiness to quit and quit attempts of cigarettes versus marijuana (p's<0.001). While 23.26% of marijuana-only and 15.13% of cigarette-only users reported readiness to quit, 41.18% of cigarette-only and 21.75% of marijuana-only users reported recent quit attempts (p's<0.001). Binary logistic regressions indicated distinct correlates of readiness to quit and quit attempts of cigarettes and marijuana. Cessation efforts of the respective products must attend to co-use with the other product to better understand relative perceptions of importance and confidence in quitting and actual cessation efforts. Copyright © 2017 Elsevier Ltd. All rights reserved.

Anxious arousal and anhedonic depression symptoms and the frequency of current marijuana use: testing the mediating role of marijuana-use coping motives among active users.

PubMed

Johnson, Kirsten A; Bonn-Miller, Marcel O; Leyro, Teresa M; Zvolensky, Michael J

2009-07-01

The present investigation examined anxious arousal and anhedonic depression symptoms in relation to frequency of past-30-day marijuana use, as well as the role of marijuana-use coping motives in terms of mediating this relation. The present sample included current young adult marijuana users (N = 154; 48.1% female; mean [SD] age = 20.75 [5.97] years) who were recruited via study flyers and printed advertisements in local newspapers placed throughout the Burlington, VT, community. After controlling for daily cigarette smoking rate, alcohol consumption, and gender, anxious arousal symptoms, but not anhedonic depression symptoms, were significantly and uniquely associated with the frequency of marijuana use. In addition, coping motives for marijuana use mediated the relation between anxious arousal symptoms and the frequency of current marijuana use. These results provide novel information related to the explanatory role of marijuana-use coping motives in the relation between anxious arousal symptoms and the frequency of marijuana use among young adult active users. Clinical implications for the current findings are discussed.

Discriminability of personality profiles in isolated and Co-morbid marijuana and nicotine users.

PubMed

Ketcherside, Ariel; Jeon-Slaughter, Haekyung; Baine, Jessica L; Filbey, Francesca M

2016-04-30

Specific personality traits have been linked with substance use disorders (SUDs), genetic mechanisms, and brain systems. Thus, determining the specificity of personality traits to types of SUD can advance the field towards defining SUD endophenotypes as well as understanding the brain systems involved for the development of novel treatments. Disentangling these factors is particularly important in highly co morbid SUDs, such as marijuana and nicotine use, so treatment can occur effectively for both. This study evaluated personality traits that distinguish isolated and co-morbid use of marijuana and nicotine. To that end, we collected the NEO Five Factor Inventory in participants who used marijuana-only (n=59), nicotine-only (n=27), both marijuana and nicotine (n=28), and in non-using controls (n=28). We used factor analyses to identify personality profiles, which are linear combinations of the five NEO Factors. We then conducted Receiver Operating Characteristics (ROC) curve analysis to test accuracy of the personality factors in discriminating isolated and co-morbid marijuana and nicotine users from each other. ROC curve analysis distinguished the four groups based on their NEO personality patterns. Results showed that NEO Factor 2 (openness, extraversion, agreeableness) discriminated marijuana and marijuana+nicotine users from controls and nicotine-only users with high predictability. Additional ANOVA results showed that the openness dimension discriminated marijuana users from nicotine users. These findings suggest that personality dimensions distinguish marijuana users from nicotine users and should be considered in prevention strategies. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Marijuana use among older adults in the U.S.A.: user characteristics, patterns of use, and implications for intervention.

PubMed

Dinitto, Diana M; Choi, Namkee G

2011-06-01

Epidemiological studies show that the number of older adults using marijuana is increasing. This study aimed to determine the correlates and patterns of marijuana use among older adults that might help health and social service providers better assist this group. Data are from the 2008 National Survey on Drug Use and Health conducted by the Substance Abuse and Mental Health Services Administration in the U.S.A. The sample consisted of 5,325 adults aged 50 years and older. Of the sample, 2.8% were past-year marijuana users. Of them, 23% had used marijuana on at least half the days of the year. Past-year users were more likely to be younger (50-64 years old), black, and not married, and they had significantly higher psychological distress scores, but they did not rate their health as poorer than others in the sample, nor did they attribute many problems, including psychological problems, as being related to their marijuana use. Nevertheless, past-year users present a high-risk profile because, in addition to frequent marijuana use, they also are more likely to smoke cigarettes, engage in binge drinking, and use other illicit drugs. Health and social service providers should be alert to the small number of routine marijuana users among the younger members of the older adult population, especially those suffering significant psychological distress, so that these individuals can be encouraged to utilize services that will help alleviate this distress and promote a healthier lifestyle and increase general well being.

Long-term heavy marijuana users make costly decisions on a gambling task.

PubMed

Whitlow, Christopher T; Liguori, Anthony; Livengood, L Brooke; Hart, Stephanie L; Mussat-Whitlow, Becky J; Lamborn, Corey M; Laurienti, Paul J; Porrino, Linda J

2004-10-05

Chronic marijuana use has been associated with impairments of learning, memory, and executive functions. Little is known, however, about the effects of marijuana use on other cognitive domains, such as decision-making, which are thought to play an important role in addiction and drug abuse. The purpose of the present study was to determine if long-term heavy marijuana users employ different decision-making strategies than individuals with minimal marijuana exposure. Volunteers were assigned to a cannabis (n = 10) or control group (n = 10) based upon history of prior marijuana use. Demographic and neuropsychological variables were evaluated, and a decision-making task--the gambling task (GT) was administered. Although few demographic and neuropsychological differences were noted between groups, marijuana users made more decisions that led to larger immediate gains despite more costly losses than controls. These data suggest that long-term heavy marijuana users may have specific deficits in the ability to balance rewards and punishments that may contribute to continued drug-taking behavior. It is unknown, however, whether the basis for such deficits might be attributed directly to marijuana exposure or pre-existing genetic or behavioral differences.

Motivational and mindfulness intervention for young adult female marijuana users

PubMed Central

de Dios, Marcel A.; Herman, Debra S.; Britton, Willoughby B.; Hagerty, Claire E.; Anderson, Bradley J.; Stein, Michael D.

2011-01-01

This pilot study tested the efficacy of a brief intervention using motivational interviewing (MI) plus mindfulness meditation (MM) to reduce marijuana use among young adult female. Thirty-four female marijuana users between the ages of 18–29 were randomized to either the intervention group (n = 22), consisting of 2 sessions of MI-MM or an assessment-only control group (n = 12). Participants’ marijuana use was assessed at baseline, 1, 2, and 3 months post-treatment. Fixed-effects regression modeling was used to analyze treatment effects. Participants randomized to the intervention group were found to use marijuana on 6.15 (z = −2.42, p=.015), 7.81 (z = −2.78, p=.005), and 6.83 (z = −2.23, p=.026) fewer days at months 1, 2, and 3, respectively, than controls. Findings from this pilot study provide preliminary evidence for the feasibility and effectiveness of a brief MI-MM for young adult female marijuana users. PMID:21940136

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

Relations Between Anxiety Sensitivity, Distress Tolerance, and Fear Reactivity to Bodily Sensations to Coping and Conformity Marijuana Use Motives Among Young Adult Marijuana Users

PubMed Central

Zvolensky, Michael J.; Marshall, Erin C.; Johnson, Kirsten; Hogan, Julianna; Bernstein, Amit; Bonn-Miller, Marcel O.

2011-01-01

The present investigation examines anxiety sensitivity, distress tolerance, and fear reactivity to bodily sensations in relation to Coping and Conformity marijuana use motives among a sample of young adult marijuana users (n = 135; 46.7% women; Mage = 20.45, SD = 5.0). After controlling for current marijuana use frequency (past 30 days), daily cigarette smoking rate, average volume of alcohol used over the past year, negative affectivity, and other marijuana use motives, anxiety sensitivity was significantly and uniquely associated with Coping and Conformity motives for marijuana use. Distress tolerance evidenced significant and unique incremental relations to Coping motives, whereas fear reactivity to bodily sensations was unrelated to any marijuana use motive. These results provide novel information related to the role of emotional sensitivity and tolerance factors as they pertain to specific types of motives for marijuana use among young adults. PMID:19186932

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…

Let's Be Blunt: Consumption Methods Matter Among Black Marijuana Smokers.

PubMed

Montgomery, LaTrice; Bagot, Kara

2016-05-01

Despite the high prevalence of blunt (i.e., hollowed-out cigars that are filled with marijuana) use among Black marijuana smokers, few studies have examined if and how blunt users differ from traditional joint users. The current study compared the prevalence and patterns of use for those who smoked blunts in the past month (i.e., blunt users) with those who used marijuana through other methods (i.e., other marijuana users). The sample included 935 Black past-month marijuana smokers participating in the 2013 National Survey on Drug Use and Health. Among past-month marijuana smokers, 73.2% were blunt users and 26.8% were other marijuana users. Overall, blunt users initiated marijuana use at an earlier age (15.9 vs. 17.3 years, p < .01) and reported more days of marijuana use in the past month (16 vs. 8 days, p < .01) than did other marijuana users. There were also differences by gender. Among females, blunt users reported a higher odds of past-year marijuana abuse or dependence (23.8%) than other marijuana users (11.2%) (adjusted odds ratio = 1.23, 95% CI [1.12, 3.17], p < .01). However, blunt-using males reported similar odds of past-year marijuana abuse or dependence (approximately 25%) as other marijuana-using males. These findings highlight the need for targeted interventions for blunt users as a subgroup of marijuana users, especially among Black females, who may be at increased risk for developing a marijuana use disorder as a result of blunt smoking.

Adolescents’ Attitudes toward Anti-marijuana Ads, Usage Intentions, and Actual Marijuana Usage

PubMed Central

Alvaro, Eusebio M.; Crano, William D.; Siegel, Jason T.; Hohman, Zachary; Johnson, Ian; Nakawaki, Brandon

2015-01-01

The association of adolescents’ appraisals of the anti-marijuana television ads used in the National Youth Anti-drug Media Campaign with future marijuana use was investigated. The 12 to 18 year old respondents (N = 2993) were first classified as users, resolute nonusers, or vulnerable nonusers (Crano, Siegel, Alvaro, Lac, & Hemovich, 2008). Usage status and the covariates of gender, age, and attitudes toward marijuana were used to predict attitudes toward the ads (Aad) in the first phase of a multi-level linear analysis. All covariates were significantly associated with Aad, as was usage status: resolute nonusers evaluated the ads significantly more positively than vulnerable nonusers and users (all p < .001), who did not differ. In the second phase, the covariates along with Aad and respondents’ usage status predicted intentions and actual usage one year after initial measurement. The lagged analysis disclosed negative associations between Aad and usage intentions, and between Aad and actual marijuana use (both p < .05); however, this association held only for users (p < .01), not vulnerable or resolute nonusers. Users reporting more positive attitudes towards the ads were less likely to report intention to use marijuana and to continue marijuana use at 1-year follow-up. These findings may inform designers of persuasion-based prevention campaigns, guiding pre-implementation efforts in the design of ads that targeted groups find appealing and thus, influential. PMID:23528197

Moderate and vigorous physical activity patterns among marijuana users: Results from the 2007-2014 National Health and Nutrition Examination Surveys.

PubMed

Vidot, Denise C; Bispo, Jordan B; Hlaing, WayWay M; Prado, Guillermo; Messiah, Sarah E

2017-09-01

The relationship between marijuana use and recreational physical activity has yet to be explored in the United States. Our aim was to examine this relationship in a population-based sample of 20-to-59-year olds (N=12,618) using 2007-2014 National Health and Nutrition Examination Surveys. Marijuana use was categorized as never (reference group), past (previously but not within the last 30-days), and current (>1day in the last 30-days) use. Current users were further categorized based on frequency of use (light, moderate, and heavy users). Physical activity was self-reported as moderate (small increase in heartrate/breathing for >10min; MPA) and vigorous (large increase in heartrate/breathing for >10min; VPA). Adjusted odds ratios (AOR) for the relationship between marijuana use and physical activity were estimated via logistic regression models. The majority of the overall sample reported either past (40.5%) or current (12.6%) marijuana use. Marijuana users had a lower prevalence of moderate physical activity than never users (current: 51.9%, past: 50.4%, never: 55.3%, p=0.001). Current (66.8%) and past (67.9%) marijuana users also had a lower prevalence of vigorous physical activity than never users (71.9%, p=0.001). Current and past users had lower odds of recreational MPA (current user AOR: 0.66, 95% CI: 0.50-0.87; past user AOR: 0.78, 95% CI: 0.62-0.98) than never users. As the frequency of marijuana use increased, time spent on MPA decreased. Results suggest that current and past marijuana users were less likely to report recreational MPA than never users. Future studies should examine the potential mechanisms and temporality of this relationship. Copyright © 2017 Elsevier B.V. All rights reserved.

Altered subjective reward valuation among drug-deprived heavy marijuana users: Aversion to uncertainty

PubMed Central

Hefner, Kathryn R.; Starr, Mark. J.; Curtin, John. J.

2015-01-01

Marijuana is the most commonly used illicit drug in the United States and its use is rising. Nonetheless, scientific efforts to clarify the risk for addiction and other harm associated with marijuana use have been lacking. Maladaptive decision-making is a cardinal feature of addiction that is likely to emerge in heavy users. In particular, distorted subjective reward valuation related to homeostatic or allostatic processes has been implicated for many drugs of abuse. Selective changes in responses to uncertainty have been observed in response to intoxication and deprivation from various drugs of abuse. To assess for these potential neuroadaptive changes in reward valuation associated with marijuana deprivation, we examined the subjective value of uncertain and certain rewards among deprived and non-deprived heavy marijuana users in a behavioral economics decision-making task. Deprived users displayed reduced valuation of uncertain rewards, particularly when these rewards were more objectively valuable. This uncertainty aversion increased with increasing quantity of marijuana use. These results suggest comparable decision-making vulnerability from marijuana use as other drugs of abuse, and highlights targets for intervention. PMID:26595464

Medical Marijuana Users are More Likely to Use Prescription Drugs Medically and Nonmedically.

PubMed

Caputi, Theodore L; Humphreys, Keith

2018-04-17

Previous studies have found a negative population-level correlation between medical marijuana availability in US states, and trends in medical and nonmedical prescription drug use. These studies have been interpreted as evidence that use of medical marijuana reduces medical and nonmedical prescription drug use. This study evaluates whether medical marijuana use is a risk or protective factor for medical and nonmedical prescription drug use. Simulations based upon logistic regression analyses of data from the 2015 National Survey on Drug Use and Health were used to compute associations between medical marijuana use, and medical and nonmedical prescription drug use. Adjusted risk ratios (RRs) were computed with controls added for age, sex, race, health status, family income, and living in a state with legalized medical marijuana. Medical marijuana users were significantly more likely (RR 1.62, 95% confidence interval [CI] 1.50-1.74) to report medical use of prescription drugs in the past 12 months. Individuals who used medical marijuana were also significantly more likely to report nonmedical use in the past 12 months of any prescription drug (RR 2.12, 95% CI 1.67-2.62), with elevated risks for pain relievers (RR 1.95, 95% CI 1.41-2.62), stimulants (RR 1.86, 95% CI 1.09-3.02), and tranquilizers (RR 2.18, 95% CI 1.45-3.16). Our findings disconfirm the hypothesis that a population-level negative correlation between medical marijuana use and prescription drug harms occurs because medical marijuana users are less likely to use prescription drugs, either medically or nonmedically. Medical marijuana users should be a target population in efforts to combat nonmedical prescription drug use.

Differences in Tobacco Product Use Among Past Month Adult Marijuana Users and Nonusers: Findings From the 2003-2012 National Survey on Drug Use and Health.

PubMed

Schauer, Gillian L; Berg, Carla J; Kegler, Michelle C; Donovan, Dennis M; Windle, Michael

2016-03-01

This study assessed differences in individual tobacco product use between past month marijuana users and nonusers, and trends in overall tobacco use and use of specific tobacco products among marijuana users. Data were obtained from 378 459 adults participating in the 2003-2012 National Survey on Drug Use and Health, a cross-sectional, household interview survey conducted annually. Data from the most recent 2 years (2011-2012) were used to assess differences in the prevalence of various tobacco products by past month marijuana status. Data from all years were used to assess historical trends in overall tobacco use, and use of cigarettes, cigars, and blunts among marijuana users; trend significance was assessed using orthogonal polynomials. From 2011-2012, the prevalence of any past month tobacco use among the 9727 past month marijuana users was 68.6% excluding blunts, and 78.3% including blunts (vs. 25.3% for nonusers, P < .0001); 77.3% of past month marijuana users reported past month combusted tobacco use (vs. 23.4% of non-MJ users, P < .0001). By product, 60.1% of past month marijuana users reported past month cigarette use, 42.0% reported past month blunt use, and 20.6% reported past month cigar use. Overall, adjusted trends in past month cigarette use decreased, while trends in past month blunt use increased; cigar use did not change. Tobacco use is highly prevalent among adult marijuana users and represents an important potential comorbidity of marijuana use. In light of increasing policies legalizing marijuana, it is critical to monitor changes in overall and specific tobacco product use. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Medical marijuana legalization and cigarette and marijuana co-use in adolescents and adults.

PubMed

Wang, Julie B; Ramo, Danielle E; Lisha, Nadra E; Cataldo, Janine K

2016-09-01

Medical marijuana legalization is associated with a higher prevalence of marijuana use which may affect cigarette use and nicotine dependence in co-users. In the present study, we examined relationships between statewide legalization of medical marijuana and prevalence of cigarette and marijuana co-use and nicotine dependence in co-using adolescents and adults. Data were analyzed from the 2013 National Survey on Drug Use and Health. We compared cigarette and marijuana co-use in the past 30days across age categories (12-64 years) by statewide medical marijuana legalization. Logistic regression models were used to estimate the odds of having nicotine dependence among current cigarette smokers who also reported past 30-day marijuana use and "ever but not current" marijuana use (vs. "never" use) adjusting for covariates including statewide legalization of medical marijuana. Overall, 5.1% of the sample reported past 30-day cigarette and marijuana co-use and a higher proportion of co-users resided in states where medical marijuana was legal compared to illegal (5.8% vs. 4.8%; p=0.0011). Co-use was associated with greater odds of having nicotine dependence compared to cigarette-only use across age categories. Odds were highest and up to 3-times higher in adolescents aged 12-17 years (OR=3.54; 95%CI: 1.81-6.92) and adults aged 50-64 years (OR=3.08; CI: 1.45-6.55). Marijuana policy could inadvertently affect cigarette and marijuana co-use and pose challenges to tobacco cessation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Marijuana use and depression among adults: Testing for causal associations.

PubMed

Harder, Valerie S; Morral, Andrew R; Arkes, Jeremy

2006-10-01

To determine whether marijuana use predicts later development of depression after accounting for differences between users and non-users of marijuana. An ongoing longitudinal survey of 12 686 men and women beginning in 1979. The National Longitudinal Survey of Youth of 1979, a nationally representative sample from the United States. A total of 8759 adults (age range 29-37 years) interviewed in 1994 had complete data on past-year marijuana use and current depression. Self-reported past-year marijuana use was tested as an independent predictor of later adult depression using the Center for Epidemiologic Studies-Depression questionnaire. Individual's propensity to use marijuana was calculated using over 50 baseline covariates. Before adjusting for group differences, the odds of current depression among past-year marijuana users is 1.4 times higher (95% CI: 1.1, 1.9) than the odds of depression among the non-using comparison group. After adjustment, the odds of current depression among past-year marijuana users is only 1.1 times higher than the comparison group (95% CI: 0.8, 1.7). Similarly, adjustment eliminates significant associations between marijuana use and depression in four additional analyses: heavy marijuana use as the risk factor, stratifying by either gender or age, and using a 4-year lag-time between marijuana use and depression. After adjusting for differences in baseline risk factors of marijuana use and depression, past-year marijuana use does not significantly predict later development of depression. These findings are discussed in terms of their relevance for understanding possible causal effects of marijuana use on depression.

New product trial, use of edibles, and unexpected highs among marijuana and hashish users in Colorado.

PubMed

Allen, Jane A; Davis, Kevin C; Duke, Jennifer C; Nonnemaker, James M; Bradfield, Brian R; Farrelly, Matthew C

2017-07-01

This study examines the relationships between trial of new marijuana or hashish products and unexpected highs, and use of edible products and unexpected highs. We conducted an online survey of 634 adult, past-year marijuana users in Colorado. We used logistic regression models to examine the relationship between new product trial or edible use and unexpected highs. In the first year that recreational marijuana was legal in Colorado, 71.4% of respondents tried a new marijuana or hashish product, and 53.6% used an edible product. Trial of new products was associated with greater odds of experiencing an unexpected high after controlling for age, gender, education, mental health status, current marijuana or hashish use, and mean amount of marijuana or hashish consumed in the past month (OR=2.13, p<0.001). Individuals who reported having used edibles had greater odds of experiencing an unexpected high, after controlling for the same set of variables (OR=1.56, p<0.05). People who try new marijuana or hashish products, or use edible marijuana or hashish products, are at greater risk for an unexpected high. It is possible that some negative outcomes associated with marijuana use and unexpected highs may be averted through a better understanding of how to use product packaging to communicate with consumers. Copyright © 2017 Elsevier B.V. All rights reserved.

Marijuana use among US tobacco users: Findings from wave 1 of the population assessment of tobacco health (PATH) study.

PubMed

Strong, David R; Myers, Mark G; Pulvers, Kim; Noble, Madison; Brikmanis, Kristin; Doran, Neal

2018-05-01

With an increase in marijuana use among adults in the United States (US), understanding the potential impact of marijuana use on tobacco use and associated behavioral and health consequences, including respiratory conditions, is necessary. Survey responses from Wave 1 of the nationally representative Population Assessment of Tobacco and Health (PATH) Study were used to assess tobacco use and marijuana use among non-current tobacco users (n = 17,952) and current established tobacco-users classified as: cigarette only users (n = 8689), e-cigarette only users (n = 437), cigar only (traditional, cigarillo, or filtered) users (n = 706), hookah only users (n = 461), smokeless tobacco only users (n = 971), cigarette + e-cigarette users (n = 709), and users of multiple tobacco products (n = 2314). When compared to non-current tobacco users, each tobacco user group except smokeless only users had higher odds (odds ratios ranging from 3.86-8.07) of reporting current marijuana use. Among current tobacco users, higher levels of tobacco dependence did not explain the relationship between tobacco use and marijuana use. Additionally, concurrent marijuana use was associated with lower odds of attempts to quit tobacco (OR = 0.86, 95% CI = 0.79, 0.94, p < 0.001) and a higher probability (OR = 1.35, 95CI = 1.21, 1.51, p < 0.01) of reporting a history of respiratory disease. The association between concurrent use of tobacco and marijuana and higher tobacco dependence and lower rates of quit attempts suggests the potential for sustained tobacco use and deleterious health effects. Further, marijuana use may represent an additive risk for respiratory harm among concurrent users of tobacco and marijuana. Copyright © 2018 Elsevier B.V. All rights reserved.

Marijuana use trajectories and academic outcomes among college students.

PubMed

Suerken, Cynthia K; Reboussin, Beth A; Egan, Kathleen L; Sutfin, Erin L; Wagoner, Kimberly G; Spangler, John; Wolfson, Mark

2016-05-01

Marijuana is the most commonly used illicit drug by college students. Prior studies have established an association between marijuana use and poor academic performance in college, but research on the frequency of marijuana use over the entire college career is limited. The study objective was to examine the association of marijuana use trajectories on academic outcomes, including senior year enrollment, plans to graduate on time, and GPA. Data were collected from a cohort of 3146 students from 11 colleges in North Carolina and Virginia at six time points across the college career. Group-based trajectory models were used to characterize longitudinal marijuana use patterns during college. Associations between marijuana trajectory groups and academic outcomes were modeled using random-effects linear and logistic regressions. Five marijuana trajectory groups were identified: non-users (69.0%), infrequent users (16.6%), decreasing users (4.7%), increasing users (5.8%), and frequent users (3.9%). Decreasing users and frequent users were more likely to drop out of college and plan to delay graduation when compared to non-users. All marijuana user groups reported lower GPAs, on average, than non-users. These results identify marijuana use patterns that put students at risk for poor academic performance in college. Students who use marijuana frequently at the beginning of the college career are especially at risk for lower academic achievement than non-users, suggesting that early intervention is critical. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Marijuana Use Trajectories and Academic Outcomes among College Students

PubMed Central

Suerken, Cynthia K.; Reboussin, Beth A.; Egan, Kathleen L.; Sutfin, Erin L.; Wagoner, Kimberly G.; Spangler, John; Wolfson, Mark

2016-01-01

Background Marijuana is the most commonly used illicit drug by college students. Prior studies have established an association between marijuana use and poor academic performance in college, but research on the frequency of marijuana use over the entire college career is limited. The study objective was to examine the association of marijuana use trajectories on academic outcomes, including senior year enrollment, plans to graduate on time, and GPA. Methods Data were collected from a cohort of 3,146 students from 11 colleges in North Carolina and Virginia at six time points across the college career. Group-based trajectory models were used to characterize longitudinal marijuana use patterns during college. Associations between marijuana trajectory groups and academic outcomes were modeled using random-effects linear and logistic regressions. Results Five marijuana trajectory groups were identified: non-users (69.0%), infrequent users (16.6%), decreasing users (4.7%), increasing users (5.8%), and frequent users (3.9%). Decreasing users and frequent users were more likely to drop out of college and plan to delay graduation when compared to non-users. All marijuana user groups reported lower GPAs, on average, than non-users. Conclusion These results identify marijuana use patterns that put students at risk for poor academic performance in college. Students who use marijuana frequently at the beginning of the college career are especially at risk for lower academic achievement than non-users, suggesting that early intervention is critical. PMID:27020322

Marijuana Use at School and Achievement-Linked Behaviors

ERIC Educational Resources Information Center

Finn, Kristin V.

2012-01-01

Marijuana remains one of the most frequently used drugs among adolescents and usage has increased in recent years. In addition to general use, many high school students use marijuana during the school day. The present study focused on achievement-linked correlates of in-school marijuana use by comparing non-users, general users, and school users…

Marijuana Primes, Marijuana Expectancies, and Arithmetic Efficiency*

PubMed Central

Hicks, Joshua A.; Pedersen, Sarah L.; McCarthy, Denis M.; Friedman, Ronald S.

2009-01-01

Objective: Previous research has shown that primes associated with alcohol influence behavior consistent with specific alcohol expectancies. The present study examined whether exposure to marijuana-related primes and marijuana expectancies interact to produce similar effects. Specifically, the present study examined whether marijuana primes and marijuana expectancies regarding cognitive and behavioral impairment interact to influence performance on an arithmetic task. Method: Two independent samples (N = 260) of undergraduate students (both marijuana users and nonusers) first completed measures of marijuana-outcome expectancies associated with cognitive and behavioral impairment and with general negative effects (Sample 2). Later in the semester, participants were exposed to marijuana-related (or neutral) primes and then completed an arithmetic task. Results: Results from Sample 1 indicated that participants who were exposed to marijuana-themed magazine covers performed more poorly on the arithmetic task if they expected that marijuana would lead to cognitive and behavioral impairment. Results from Sample 2 indicated that, for marijuana users, cognitive and behavioral impairment expectancies, but not expectancies regarding general negative effects, similarly moderated arithmetic performance for participants exposed to marijuana-related words. Conclusions: Results support the hypothesis that the implicit activation of specific marijuana-outcome expectancies can influence cognitive processes. Implications for research on marijuana are discussed. PMID:19371490

Marijuana alters the human cerebellar clock.

PubMed

O'Leary, Daniel S; Block, Robert I; Turner, Beth M; Koeppel, Julie; Magnotta, Vincent A; Ponto, Laura Boles; Watkins, G Leonard; Hichwa, Richard D; Andreasen, Nancy C

2003-06-11

The effects of marijuana on brain perfusion and internal timing were assessed using [15O] water PET in occasional and chronic users. Twelve volunteers who smoked marijuana recreationally about once weekly, and 12 volunteers who smoked daily for a number of years performed a self-paced counting task during PET imaging, before and after smoking marijuana and placebo cigarettes. Smoking marijuana increased rCBF in the ventral forebrain and cerebellar cortex in both groups, but resulted in significantly less frontal lobe activation in chronic users. Counting rate increased after smoking marijuana in both groups, as did a behavioral measure of self-paced tapping, and both increases correlated with rCBF in the cerebellum. Smoking marijuana appears to accelerate a cerebellar clock altering self-paced behaviors.

The effects of chronic marijuana use on circadian entrainment.

PubMed

Whitehurst, Lauren N; Fogler, Kethera; Hall, Kate; Hartmann, Matthew; Dyche, Jeff

2015-05-01

Animal literature suggests a connection between marijuana use and altered circadian rhythms. However, the effect has not yet been demonstrated in humans. The present study examined the effect of chronic marijuana use on human circadian function. Participants consisted of current users who reported smoking marijuana daily for at least a year and non-marijuana user controls. Participants took a neurocognitive assessment, wore actigraphs and maintained sleep diaries for three weeks. While no significant cognitive changes were found between groups, data revealed that chronic marijuana use may act as an additional zeitgeber and lead to increased entrainment in human users.

A comparison of male users and nonusers of marijuana on the perceived harmfulness of drugs.

PubMed

Primavera, L H; Pascal, R

1986-01-01

Subjects (n = 108) who volunteered to participate in a study in which they expected to smoke marijuana were asked, as part of a screening procedure, to rate the harmfulness of a number of illicit drugs including marijuana. Subjects were separated into three groups according to their reported history of use of marijuana. The three groups were: naive users (at least 1 but no more than 25 incidences of use in a lifetime), light users (1 to 3 incidences of use per week), and heavy users (at least 5 incidences of use per week). Groups did not differ in terms of their perceived harmfulness of any of the drugs. Cluster analyses of the results for each group and for the total group indicated three distinct clusters: the drugs perceived to be the most harmful were heroin, morphine, and LSD; drugs perceived to be less harmful were cocaine, amphetamines, barbiturates, and nicotine; and the drugs perceived to be the least harmful were caffeine and marijuana, with marijuana being judged the least harmful of all the drugs.

Marijuana use trajectories during college predict health outcomes nine years post-matriculation

PubMed Central

Arria, Amelia M.; Caldeira, Kimberly M.; Bugbee, Brittany A.; Vincent, Kathryn B.; O’Grady, Kevin E.

2015-01-01

Background Several studies have linked marijuana use with a variety of health outcomes among young adults. Information about marijuana’s long-term health effects is critically needed. Methods Data are from a ten-year study of 1,253 young adults originally recruited as first-year college students and assessed annually thereafter. Six trajectories of marijuana use during college (Non-Use, Low-Stable, Early-Decline, College-Peak, Late-Increase, Chronic) were previously derived using latent variable growth mixture modeling. Nine health outcomes assessed in Year 10 (modal age 27) were regressed on a group membership variable for the six group trajectories, holding constant demographics, baseline health status, and alcohol and tobacco trajectory group membership. Results Marijuana trajectory groups differed significantly on seven of the nine outcomes (functional impairment due to injury, illness, or emotional problems; psychological distress; subjective well-being; and mental and physical health service utilization; all ps<.001), but not on general health rating or body mass index. Non-Users fared better than the Late-Increase and Chronic groups on most physical and mental health outcomes. The declining groups (Early-Decline, College-Peak) fared better than the Chronic group on mental health outcomes. The Late-Increase group fared significantly worse than the stable groups (Non-Use, Low-Stable, Chronic) on both physical and mental health outcomes. Conclusions Even occasional or time-limited marijuana use might have adverse effects on physical and mental health, perhaps enduring after several years of moderation or abstinence. Reducing marijuana use frequency might mitigate such effects. Individuals who escalate their marijuana use in their early twenties might be at especially high risk for adverse outcomes. PMID:26778758

Use of Protective Behavioral Strategies among Young Adult Veteran Marijuana Users.

PubMed

Pedersen, Eric R; Villarosa-Hurlocker, Margo C; Prince, Mark A

2018-01-01

Young adult veterans are at risk for problematic marijuana use and associated consequences, which is partially due to their high rates of Posttraumatic Stress Disorder (PTSD), depression, and problematic substance use. Veterans tend to endorse more severe and chronic mental health symptoms compared to their civilian counterparts and they identify marijuana use as a method to cope with their symptoms. Given the prevalence of marijuana use among veterans in the community and in clinical settings, it is important to explore the factors that may help minimize harm associated with use for those that choose to use the drug. The present study sought to examine the impact of protective behavioral strategies on the relationship between mental health symptoms and marijuana use and consequences in a sample of 180 young adult veteran marijuana users. Participants were recruited via social media advertisements and completed measures of marijuana use and consequences, protective behavioral strategies, and PTSD and depression symptoms. Findings indicated that more frequent use of protective behavioral strategies was associated with less marijuana use and consequences. Participants who screened positive for PTSD or depression reported more marijuana consequences than did those not positive on these screeners. Regression analyses revealed protective strategies moderated the relationship between PTSD and marijuana consequences such that young veterans who endorsed more PTSD symptoms and infrequent use of protective strategies reported the most marijuana consequences. No moderating effects were found for the relationship between depression and marijuana consequences. Findings have clinical implications for working with young veterans.

Prevalence, correlates, and trends in tobacco use and cessation among current, former, and never adult marijuana users with a history of tobacco use, 2005-2014.

PubMed

Schauer, Gillian L; King, Brian A; McAfee, Timothy A

2017-10-01

Approximately 70% of current (past 30-day) adult marijuana users are current tobacco users, which may complicate tobacco cessation. We assessed prevalence and trends in tobacco cessation among adult ever tobacco users, by marijuana use status. Data came from the National Survey on Drug Use and Health, a cross-sectional, nationally representative, household survey of U.S. civilians. Analyses included current, former, and never marijuana users aged≥18 reporting ever tobacco use (cigarette, cigar, chew/snuff). We computed weighted estimates (2013-2014) of current tobacco use, recent tobacco cessation (quit 30days to 12months), and sustained tobacco cessation (quit>12months) and adjusted trends in tobacco use and cessation (2005-2014) by marijuana use status. We also assessed the association between marijuana and tobacco use status. In 2013-2014, among current adult marijuana users reporting ever tobacco use, 69.1% were current tobacco users (vs. 38.5% of former marijuana users, p<0.0001, and 28.2% of never marijuana users, p<0.0001); 9.1% reported recent tobacco cessation (vs. 8.4% of former marijuana users, p<0.01, and 6.3% of never marijuana users, p<0.001), and 21.8% reported sustained tobacco cessation (vs. 53.1% of former marijuana users, p<0.01, and 65.5% of never marijuana users, p<0.0001). Between 2005 and 2014, current tobacco use declined and sustained tobacco cessation increased among all marijuana use groups. Current marijuana users who ever used tobacco had double the prevalence (vs. never-marijuana users) of current tobacco use, and significantly lower sustained abstinence. Interventions addressing tobacco cessation in the context of use of marijuana and other substances may be warranted. Copyright © 2017 Elsevier Ltd. All rights reserved.

Twitter chatter about marijuana.

PubMed

Cavazos-Rehg, Patricia A; Krauss, Melissa; Fisher, Sherri L; Salyer, Patricia; Grucza, Richard A; Bierut, Laura Jean

2015-02-01

We sought to examine the sentiment and themes of marijuana-related chatter on Twitter sent by influential Twitter users and to describe the demographics of these Twitter users. We assessed the sentiment and themes of a random sample (n = 7,000) of influential marijuana-related tweets (sent from February 5, 20114, to March 5, 2014). Demographics of the users tweeting about marijuana were inferred using a social media analytics company (Demographics Pro for Twitter). Most marijuana-related tweets reflected a positive sentiment toward marijuana use, with pro-marijuana tweets outnumbering anti-marijuana tweets by a factor of greater than 15. The most common theme of pro-marijuana tweets included the Tweeter stating that he/she wants/plans to use marijuana, followed by tweeting about frequent/heavy/or regular marijuana use, and that marijuana has health benefits and/or should be legalized. Tweeters of marijuana-related content were younger and a greater proportion was African-American compared with the Twitter average. Marijuana Twitter chatter sent by influential Twitter users tends to be pro-marijuana and popular among African-Americans and youth/young adults. Marijuana-related harms may afflict some individuals; therefore, our findings should be used to inform online and offline prevention efforts that work to target individuals who are most at risk for harms associated with marijuana use. Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Verbal learning in marijuana users seeking treatment: a comparison between depressed and non-depressed samples.

PubMed

Roebke, Patrick V; Vadhan, Nehal P; Brooks, Daniel J; Levin, Frances R

2014-07-01

Both individuals with marijuana use and depressive disorders exhibit verbal learning and memory decrements. This study investigated the interaction between marijuana dependence and depression on learning and memory performance. The California Verbal Learning Test-Second Edition (CVLT-II) was administered to depressed (n = 71) and non-depressed (n = 131) near-daily marijuana users. The severity of depressive symptoms was measured by the self-rated Beck Depression Inventory (BDI-II) and the clinician-rated Hamilton Depression Rating Scale (HAM-D). Multivariate analyses of covariance statistics (MANCOVA) were employed to analyze group differences in cognitive performance. Pearson's correlation coefficients were calculated to examine the relative associations between marijuana use, depression and CVLT-II performance. Findings from each group were compared to published normative data. Although both groups exhibited decreased CVLT-II performance relative to the test's normative sample (p < 0.05), marijuana-dependent subjects with a depressive disorder did not perform differently than marijuana-dependent subjects without a depressive disorder (p > 0.05). Further, poorer CVLT-II performance was modestly associated with increased self-reported daily amount of marijuana use (corrected p < 0.002), but was not significantly associated with increased scores on measures of depressive symptoms (corrected p > 0.002). These findings suggest an inverse association between marijuana use and verbal learning function, but not between depression and verbal learning function in regular marijuana users.

METABOLIC EFFECTS OF MARIJUANA USE AMONG BLACKS

PubMed Central

Racine, C.; Vincent, M.; Rogers, A.; Donat, M.; Ojike, N. I.; Necola, O.; Yousef, E.; Masters-Israilov, A.; Jean-Louis, G.; McFarlane, S. I.

2015-01-01

Background Increased legalization of marijuana has resulted in renewed interest in its effects on body weight and cardiometabolic risk. Conflicting data exist regarding marijuana effects on body weight, waist circumference as well as lipid profiles, blood pressure and cardiovascular disease. Furthermore, there is a dearth of data available on this effect in the black population. Objective To assess the metabolic profile and cardiovascular risk factors as well as body weight and waist circumference among urban black marijuana users. Methods A cross sectional study design involving 100 patients seen in a Family Practice clinic at University hospital of Brooklyn, NY, USA, over a period of 3 months from January 2014 to March 2014. Participants were administered a questionnaire regarding marijuana use, and other associated behaviors. Socio-demographic, laboratory, and clinical data were collected. We report measures of central tendencies, and dispersion for continuous variables and the frequency of distribution for categorical variables. Results Of the 100 patients surveyed, 57% were females. The mean (±SEM) age of the entire cohort was 46.3 years±1.5; range, 19–78 years. The mean body mass index (BMI) was 29.6 kg/m2±0.73; SBP=128.0 mmHg±1.69; DBP=76.1 mmHg±1.17. Current marijuana users had the lowest waist circumference compared to former or never users respectively (32.9±0.66 vs. 35.9±0.88 vs. 33.4±0.74), p<0.01. Diastolic blood pressure in mmHg was significantly higher among former marijuana users compared to current or never users, (80.0±2.1 vs. 73.3±2.3 vs. 73.4±1.6), p<0.01. Current marijuana users showed a tendency (not statistically significant) towards lower total cholesterol, Triglycerides (TG), High Density Lipoprotein (HDL)-cholesterol, Low Density Lipoprotein (LDL)-cholesterol, body mass index (BMI) and systolic blood pressure, compared to former users or never users. Conclusion Current marijuana use is associated with significantly lower waist

Use of Marijuana Edibles by Adolescents in California

PubMed Central

Friese, Bettina; Slater, Michael D.; Battle, Robynn S.

2017-01-01

We explored how adolescent marijuana edible users differ in regards to marijuana use and related beliefs from marijuana users who do not use edibles. We analyzed California Healthy Kids Survey data collected in one Northern California school district with a racially and ethnically diverse student population. Survey respondents were youth in grades 9 – 12. Overall, 33% of respondents reported having used marijuana in their lifetime, and 50% of lifetime marijuana users reported using marijuana in the past 30 days. Seventy-two percent of lifetime marijuana users and 82% of past month marijuana users reported having used edibles in their lifetime. Comparing marijuana users who have never used edibles to those users who have, we found that edible users reported using marijuana more frequently in their lifetime. Edible users were also more likely to have used marijuana in the past 30 days, more frequently in the past 30 days, more likely on school property and more frequently on school property. Edible users and non-users differed in their perceptions of risk; edible users were less likely to agree that edible use is very risky. Edible users also reported a younger age of first marijuana use and more attempts to stop using marijuana than non-edible users. Multi-level regression analyses indicate that prevalence of edible use among marijuana users was related to perceived risk of edible use. Perceived risk of edible use among marijuana users was higher among marijuana users who do not use edibles, females, and those youth who perceive school rules to be clear. The findings indicate that prevalence of edible use is high among marijuana users, especially frequent users. PMID:28470448

A latent class analysis of poly-marijuana use among young adults.

PubMed

Krauss, Melissa J; Rajbhandari, Biva; Sowles, Shaina J; Spitznagel, Edward L; Cavazos-Rehg, Patricia

2017-12-01

With more states legalizing marijuana use, the marijuana industry has grown, introducing a variety of marijuana products. Our study explores the use of multiple marijuana products (poly-marijuana use) and the characteristics associated with this behavior. Past-month marijuana users aged 18-34years were surveyed online via an existing online panel (n=2444). Participants answered questions about past-month use of three types of marijuana (plant-based, concentrates, edibles), marijuana use patterns, and driving after use. Latent class analysis was used to identify subgroups of marijuana users. Four classes of marijuana users were identified: Light plant users, who used only plant-based products infrequently and were unlikely to drive after use (32%); Heavy plant users, who used mainly plant-based products frequently, multiple times per day, and were likely to drive after use (37%); Plant and concentrates users, who used plant-based products heavily and concentrates at least infrequently, used multiple times per day, and were likely to drive after use (20%); Light plant and edibles users, who used both products infrequently and were unlikely to drive after use (10%). Those in legal marijuana states were more likely to belong to the poly-marijuana groups. Our findings reflect the increase in popularity of new marijuana products in legal states and suggest that heavy user groups, including concentrates users, are associated with driving after use. As various forms of marijuana use increases, monitoring and surveillance of the use of multiple types of marijuana will be important for determining potential varying impacts on physiological and social consequences. Copyright © 2017 Elsevier Ltd. All rights reserved.

Verbal learning in marijuana users seeking treatment: a comparison between depressed and non-depressed samples

PubMed Central

Roebke, Patrick V.; Vadhan, Nehal P.; Brooks, Daniel J.; Levin, Frances R.

2014-01-01

Background: Both individuals with marijuana use and depressive disorders exhibit verbal learning and memory decrements. Objectives: This study investigated the interaction between marijuana dependence and depression on learning and memory performance. Methods: The California Verbal Learning Test – Second Edition (CVLT-II) was administered to depressed (n=71) and non-depressed (n=131) near-daily marijuana users. The severity of depressive symptoms was measured by the self-rated Beck Depression Inventory (BDI-II) and the clinician-rated Hamilton Depression Rating Scale (HAM-D). Multivariate analyses of covariance statistics (MANCOVA) were employed to analyze group differences in cognitive performance. Pearson’s correlation coefficients were calculated to examine the relative associations between marijuana use, depression and CVLT-II performance. Findings from each group were compared to published normative data. Results: Although both groups exhibited decreased CVLT-II performance relative to the test’s normative sample (p<0.05), marijuana-dependent subjects with a depressive disorder did not perform differently than marijuana-dependent subjects without a depressive disorder (p>0.05). Further, poorer CVLT-II performance was modestly associated with increased self-reported daily amount of marijuana use (corrected p<0.002), but was not significantly associated with increased scores on measures of depressive symptoms (corrected p>0.002). Conclusion: These findings suggest an inverse association between marijuana use and verbal learning function, but not between depression and verbal learning function in regular marijuana users. PMID:24918839

Predictors of Recent Marijuana Use and Past Year Marijuana Use Among a National Sample of Hispanic Youth.

PubMed

King, Keith A; Vidourek, Rebecca A; Merianos, Ashley L; Bartsch, Lauren A

2015-01-01

Marijuana use rates remain higher among Hispanic youth compared to youth from other ethnic groups. The purpose of the study was to examine if sex, age, authoritarian parenting, perceived school experiences, lifetime depression, legal involvement, and perceived social norms of marijuana use predicted recent marijuana use and past year marijuana use among Hispanic youth. The participants of this study were a nationwide sample of Hispanic youth (n = 3,457) in the United States. A secondary data analysis of the 2012 National Survey on Drug Use and Health was performed. Unadjusted odds ratios were computed via univariate logistic regression analyses and all statistically significant variables were retained and included in the final multiple logistic regression analyses. Recent marijuana use was operationally defined as use within the past 30 days, and marijuana use in the past year was defined as use within the past year. Results indicated that 7.5% of Hispanic youth used within the past month and 14.5% of Hispanic youth used within the past year. Results revealed that significant predictors for recent use were age, authoritarian parenting, perceived school experiences, legal involvement, and perceived social norms of youth marijuana use. Predictors for past year were age, perceived school experiences, legal involvement, and perceived social norms of youth marijuana use. Findings from this study can be used to address the public health problem of marijuana use among Hispanic youth that is ultimately contributing to health disparities among this ethnic group nationwide. Recommendations for future studies are included.

E-cigarette use and subsequent cigarette and marijuana use among Hispanic young adults.

PubMed

Unger, Jennifer B; Soto, Daniel W; Leventhal, Adam

2016-06-01

Electronic cigarettes (e-cigarettes) could have a multifaceted effect on public health by changing the likelihood that: (a) non-smokers and non-users of marijuana subsequently transition to cigarette and marijuana use, respectively, and/or: (b) cigarette smokers subsequently quit smoking. We analyzed data from a longitudinal study of Hispanic young adults in Los Angeles, California to determine whether e-cigarette use is associated with subsequent cigarette or marijuana use over a one-year period. Survey data were collected from 1332 Hispanic young adults (59% female, mean age=22.7 years, SD=0.39 years) in 2014 and 2015. Logistic regression analyses examined the association between e-cigarette use in 2014 and cigarette/marijuana use in 2015, controlling for age, sex, and other substance use. In 2014, prevalence of past-month use was 9% for e-cigarettes, 21% for cigarettes, and 23% for marijuana. Among past-month cigarette nonsmokers in 2014, those who were past-month e-cigarette users in 2014 were over 3 times more likely to be past-month cigarette smokers in 2015, compared with those who did not report past-month e-cigarette use in 2014 (26% vs. 7%; OR=3.32, 95% CI=1.55, 7.10). Among past-month marijuana non-users in 2014, those who were past-month e-cigarette users in 2014 were nearly 2 times more likely to be past-month marijuana users in 2015 (24% vs. 12%;OR=1.97, 95% CI=1.01, 3.86). Among past-month cigarette and marijuana users in 2014, e-cigarette use in 2014 was not associated with a change cigarette and marijuana use, respectively, in 2015. Among Hispanic young adults, e-cigarettes could increase the likelihood of transitioning from non-user to user of cigarettes or marijuana and was not associated with smoking cessation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Marijuana abstinence effects in marijuana smokers maintained in their home environment.

PubMed

Budney, A J; Hughes, J R; Moore, B A; Novy, P L

2001-10-01

Although withdrawal symptoms are commonly reported by persons seeking treatment for marijuana dependence, the validity and clinical significance of a marijuana withdrawal syndrome has not been established. This controlled outpatient study examined the reliability and specificity of the abstinence effects that occur when daily marijuana users abruptly stop smoking marijuana. Twelve daily marijuana smokers were assessed on 16 consecutive days during which they smoked marijuana as usual (days 1-5), abstained from smoking marijuana (days 6-8), returned to smoking marijuana (days 9-13), and again abstained from smoking marijuana (days 14-16). An overall measure of withdrawal discomfort increased significantly during the abstinence phases and returned to baseline when marijuana smoking resumed. Craving for marijuana, decreased appetite, sleep difficulty, and weight loss reliably changed across the smoking and abstinence phases. Aggression, anger, irritability, restlessness, and strange dreams increased significantly during one abstinence phase, but not the other. Collateral observers confirmed participant reports of these symptoms. This study validated several specific effects of marijuana abstinence in heavy marijuana users, and showed they were reliable and clinically significant. These withdrawal effects appear similar in type and magnitude to those observed in studies of nicotine withdrawal.

Medical marijuana laws in 50 states: investigating the relationship between state legalization of medical marijuana and marijuana use, abuse and dependence

PubMed Central

Cerdá, Magdalena; Wall, Melanie; Keyes, Katherine M; Galea, Sandro; Hasin, Deborah

2011-01-01

Background Marijuana is the most frequently used illicit substance in the United States. Little is known of the role that macro-level factors, including community norms and laws related to substance use, play in determining marijuana use, abuse and dependence. We tested the relationship between state-level legalization of medical marijuana and marijuana use, abuse, and dependence. Methods We used the second wave of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), a national survey of adults aged 18+ (n=34,653). Selected analyses were replicated using the National Survey on Drug Use and Health (NSDUH), a yearly survey of ~68,000 individuals aged 12+. We measured past-year cannabis use and DSM-IV abuse/dependence. Results In NESARC, residents of states with medical marijuana laws had higher odds of marijuana use (OR: 1.92; 95% CI: 1.49-2.47) and marijuana abuse/dependence (OR: 1.81; 95% CI: 1.22-2.67) than residents of states without such laws. Marijuana abuse/dependence was not more prevalent among marijuana users in these states (OR: 1.03; 95% CI: 0.67-1.60), suggesting that the higher risk for marijuana abuse/dependence in these states was accounted for by higher rates of use. In NSDUH, states that legalized medical marijuana also had higher rates of marijuana use. Conclusions States that legalized medical marijuana had higher rates of marijuana use. Future research needs to examine whether the association is causal, or is due to an underlying common cause, such as community norms supportive of the legalization of medical marijuana and of marijuana use. PMID:22099393

Prevalence of medical marijuana use in California, 2012.

PubMed

Ryan-Ibarra, Suzanne; Induni, Marta; Ewing, Danielle

2015-03-01

The US Drug Enforcement Agency classifies marijuana as an illegal substance, yet in 22 states marijuana is legal for medicinal use. In 1996, California legalised the use of marijuana for medicinal purposes, but population-based data describing medical marijuana users in the state has not been available. Our aim was to examine the demographic differences between users and non-users of medical marijuana in California utilising population-based data. We used data from the California Behavioral Risk Factor Surveillance System 2012, an annual, random-digit-dial state-wide telephone survey that collects health data from a representative adult sample (n = 7525). Age-adjusted prevalence rates were estimated. Five percent of adults in California reported ever using medical marijuana, and most users believed that medical marijuana helped alleviate symptoms or treat a serious medical condition. Prevalence was similar when compared by gender, education and region. Prevalence of ever using medical marijuana was highest among white adults and younger adults ages 18-24 years, although use was reported by every racial/ethnic and age group examined in our study and ranged from 2% to 9%. Our study's results lend support to the idea that medical marijuana is used equally by many groups of people and is not exclusively used by any one specific group. As more states approve marijuana use for medical purposes, it is important to track medical marijuana use as a health-related behaviour and risk factor. © 2014 Australasian Professional Society on Alcohol and other Drugs.

Marijuana use and risk of lung cancer: a 40-year cohort study.

PubMed

Callaghan, Russell C; Allebeck, Peter; Sidorchuk, Anna

2013-10-01

Cannabis (marijuana) smoke and tobacco smoke contain many of the same potent carcinogens, but a critical-yet unresolved-medical and public-health issue is whether cannabis smoking might facilitate the development of lung cancer. The current study aimed to assess the risk of lung cancer among young marijuana users. A population-based cohort study examined men (n = 49,321) aged 18-20 years old assessed for cannabis use and other relevant variables during military conscription in Sweden in 1969-1970. Participants were tracked until 2009 for incident lung cancer outcomes in nationwide linked medical registries. Cox regression modeling assessed relationships between cannabis smoking, measured at conscription, and the hazard of subsequently receiving a lung cancer diagnosis. At the baseline conscription assessment, 10.5 % (n = 5,156) reported lifetime use of marijuana and 1.7 % (n = 831) indicated lifetime use of more than 50 times, designated as "heavy" use. Cox regression analyses (n = 44,284) found that such "heavy" cannabis smoking was significantly associated with more than a twofold risk (hazard ratio 2.12, 95 % CI 1.08-4.14) of developing lung cancer over the 40-year follow-up period, even after statistical adjustment for baseline tobacco use, alcohol use, respiratory conditions, and socioeconomic status. Our primary finding provides initial longitudinal evidence that cannabis use might elevate the risk of lung cancer. In light of the widespread use of marijuana, especially among adolescents and young adults, our study provides important data for informing the risk-benefit calculus of marijuana smoking in medical, public-health, and drug-policy settings.

Modulation of risk-taking in marijuana users by transcranial direct current stimulation (tDCS) of the dorsolateral prefrontal cortex (DLPFC).

PubMed

Boggio, Paulo S; Zaghi, Soroush; Villani, Ana Beatriz; Fecteau, Shirley; Pascual-Leone, Alvaro; Fregni, Felipe

2010-12-01

Cognitive deficits that are reported in heavy marijuana users (attention, memory, affect perception, decision-making) appear to be completely reversible after a prolonged abstinence period of about 28 days. However, it remains unclear whether the reversibility of these cognitive deficits indicates that (1) chronic marijuana use is not associated with long-lasting changes in cortical networks or (2) that such changes occur but the brain adapts to and compensates for the drug-induced changes. Therefore, we examined whether chronic marijuana smokers would demonstrate a differential pattern of response in comparison to healthy volunteers on a decision-making paradigm (Risk Task) while undergoing sham or active transcranial direct current stimulation (tDCS) of the dorsolateral prefrontal cortex (DLPFC). Twenty-five chronic marijuana users who were abstinent for at least 24h were randomly assigned to receive left anodal/right cathodal tDCS of DLPFC (n=8), right anodal/left cathodal tDCS of DLPFC (n=9), or sham stimulation (n=8); results on Risk Task during sham/active tDCS were compared to healthy volunteers from a previously published dataset. Chronic marijuana users demonstrated more conservative (i.e. less risky) decision-making during sham stimulation. While right anodal stimulation of the DLPFC enhanced conservative decision-making in healthy volunteers, both right anodal and left anodal DLPFC stimulation increased the propensity for risk-taking in marijuana users. These findings reveal alterations in the decision-making neural networks among chronic marijuana users. Finally, we also assessed the effects of tDCS on marijuana craving and observed that right anodal/left cathodal tDCS of DLPFC is significantly associated with a diminished craving for marijuana. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Marijuana: Facts for Teens.

ERIC Educational Resources Information Center

National Inst. on Drug Abuse (DHHS), Rockville, MD. Div. of Research.

Using a question and answer format, this booklet is designed to inform teens about the dangers of marijuana usage. Inset facts about marijuana and teen perspectives compliment the following topics: (1) What is marijuana? (2) How is marijuana used? (3) How long does marijuana stay in the user's body? (4) How many teens smoke marijuana? (5) Why do…

Predicting Self-Initiated Marijuana Use Cessation among Youth at Continuation High Schools.

PubMed

Little, Melissa A; Spruijt-Metz, Donna; Pokhrel, Pallav; Sun, Ping; Rohrbach, Louise Ann; Sussman, Steve

2013-01-01

The current article reports a large scale study of the prediction of marijuana use cessation among individuals attending alternative high schools who were regular users at baseline. Based on the Triadic Influence Theory, predictors of marijuana use cessation at 1-year follow-up were organized by type of influence (e.g., interpersonal, cultural and attitudinal, and intrapersonal) and level of influence (e.g., distal and ultimate). Among the 522 students who were past 30-day marijuana users at baseline, quitting was defined as having not used marijuana in the last 30 days at 1-year follow-up (43% of baseline users). To account for the level of influence we employed a theory-based analytic strategy, hierarchical regression. In the final multivariate model, lower level of baseline marijuana use and less of a likelihood to endorse pro-drug-use myths remained predictors of marijuana use cessation 1-year later. Implications of these findings include the need to develop cessation programs that reduce psychological dependence on marijuana use, and correct cognitive misperceptions about drug use in order to help adolescents make decisions that lead to health-promoting behaviors.

Marijuana Use Among 10th Grade Students - Washington, 2014.

PubMed

Shah, Anar; Stahre, Mandy

2016-12-30

Some studies have suggested that long-term, regular use of marijuana starting in adolescence might impair brain development and lower intelligence quotient (1,2). Since 2012, purchase of recreational or retail marijuana has become legal for persons aged ≥21 years in the District of Columbia, Alaska, California, Colorado, Maine, Massachusetts, Nevada, Oregon, and Washington, raising concern about increased marijuana access by youths. The law taxing and regulating recreational or retail marijuana was approved by Washington voters in 2012 and the first retail licenses were issued in July 2014; medical marijuana use has been legal since 1998. To examine the prevalence, characteristics, and behaviors of current marijuana users among 10th grade students, the Washington State Department of Health analyzed data from the state's 2014 Healthy Youth Survey (HYS) regarding current marijuana use. In 2014, 18.1% of 10th grade students (usually aged 15-16 years) reported using marijuana during the preceding 30 days; of these students, 32% reported using it on ≥10 days. Among the marijuana users, 65% reported obtaining marijuana through their peer networks, which included friends, older siblings, or at a party. Identification of comprehensive and sustainable public health interventions are needed to prevent and reduce youth marijuana use. Establishment of state and jurisdiction surveillance of youth marijuana use could be useful to anticipate and monitor the effects of legalization and track trends in use before states consider legalizing recreational or retail marijuana.

A Comparison of Marijuana Users and Nonusers On A Number of Personality Variables

ERIC Educational Resources Information Center

Simon, William E.; And Others

1974-01-01

The present study compares marijuana users and nonusers in terms of (a) psychological needs, (b) self-descriptions, (c) self-esteem, (d) academic achievement, (e) ordinal position of birth, and (f) attitudes toward the legalization of various items. Some significant differences were reported between groups of users. (Author/PC)

Marijuana's acute effects on cognitive bias for affective and marijuana cues.

PubMed

Metrik, Jane; Aston, Elizabeth R; Kahler, Christopher W; Rohsenow, Damaris J; McGeary, John E; Knopik, Valerie S

2015-10-01

Marijuana produces acute increases in positive subjective effects and decreased reactivity to negative affective stimuli, though may also acutely induce anxiety. Implicit attentional and evaluative processes may explicate marijuana's ability to acutely increase positive and negative emotions. This within-subjects study examined whether smoked marijuana with 2.7-3.0% delta-9-tetrahydrocannabinol (THC), relative to placebo, acutely changed attentional processing of rewarding and negative affective stimuli as well as marijuana-specific stimuli. On 2 separate days, regular marijuana users (N = 89) smoked placebo or active THC cigarette and completed subjective ratings of mood, intoxication, urge to smoke marijuana, and 2 experimental tasks: pleasantness rating (response latency and perceived pleasantness of affective and marijuana-related stimuli) and emotional Stroop (attentional bias to affective stimuli). On the pleasantness rating task, active marijuana increased response latency to negatively valenced and marijuana-related (vs. neutral) visual stimuli, beyond a general slowing of response. Active marijuana also increased pleasantness ratings of marijuana images, although to a lesser extent than placebo due to reduced marijuana urge after smoking. Overall, active marijuana did not acutely change processing of positive emotional stimuli. There was no evidence of attentional bias to affective word stimuli on the emotional Stroop task with the exception of attentional bias to positive word stimuli in the subgroup of marijuana users with cannabis dependence. Marijuana may increase allocation of attentional resources toward marijuana-specific and negatively valenced visual stimuli without altering processing of positively valenced stimuli. Marijuana-specific cues may be more attractive with higher levels of marijuana craving and less wanted with low craving levels. (c) 2015 APA, all rights reserved).

Planting the seed for marijuana use: Changes in exposure to medical marijuana advertising and subsequent adolescent marijuana use, cognitions, and consequences over seven years.

PubMed

D'Amico, Elizabeth J; Rodriguez, Anthony; Tucker, Joan S; Pedersen, Eric R; Shih, Regina A

2018-05-10

Marijuana use during adolescence is associated with neurocognitive deficits and poorer functioning across several domains. It is likely that more states will pass both medical and recreational marijuana legalization laws in the coming elections; therefore, we must begin to look more closely at the longitudinal effects of medical marijuana (MM) advertising on marijuana use among adolescents so that we can better understand effects that this advertising may have on their subsequent marijuana use and related outcomes. We followed two cohorts of 7th and 8th graders (mean age 13) recruited from school districts in Southern California from 2010 until 2017 (mean age 19) to examine effects of MM advertising on adolescents' marijuana use, cognitions, and consequences over seven years. Latent growth models examined trajectories of self-reported exposure to medical marijuana ads in the past three months and trajectories of use, cognitions, and consequences. Higher average exposure to MM advertising was associated with higher average use, intentions to use, positive expectancies, and negative consequences. Similarly, higher rates of change in MM advertising exposure were associated with higher rates of change in use, intentions, expectancies, and consequences over seven years. Results suggest that exposure to MM advertising may not only play a significant role in shaping attitudes about marijuana, but may also contribute to increased marijuana use and related negative consequences throughout adolescence. This highlights the importance of considering regulations for marijuana advertising, similar to regulations in place for the promotion of tobacco and alcohol in the U.S. Copyright © 2018. Published by Elsevier B.V.

Marijuana: Facts for Teens. Revised.

ERIC Educational Resources Information Center

National Inst. on Drug Abuse (DHEW/PHS), Rockville, MD.

This booklet provides teenagers with information concerning the use of marijuana. It is presented in a question/answer format. The following sixteen questions are briefly answered: What is marijuana? How is marijuana used? How long does marijuana stay in the user's body? How many teens smoke marijuana? Why do young people use marijuana? What…

Relationship between marijuana and other illicit drug use and depression/suicidal thoughts among late middle-aged and older adults.

PubMed

Choi, Namkee G; DiNitto, Diana M; Marti, C Nathan; Choi, Bryan Y

2016-04-01

Despite growing numbers of older-adult illicit drug users, research on this topic is rare. This study examined the relationship between marijuana and/or other illicit drug use and major depressive episode (MDE) and serious suicidal thoughts among those aged 50+ years in the USA. The public use files of the 2008 to 2012 US National Survey on Drug Use and Health (NSDUH) provided data on 29,634 individuals aged 50+ years. Logistic regression analysis was used to test hypothesized associations between past-year marijuana and/or other illicit drug use and MDE and serious suicidal thoughts. Nearly 6% of the 50+ years age group reported past-year marijuana and/or other illicit drug use. Compared to non-users of any illicit drug, the odds of past-year MDE among those who used marijuana only, other illicit drugs only, and marijuana and other illicit drugs were 1.54 (95% CI = 1.17-2.03), 2.75 (95% CI = 1.75-4.33), and 2.12 (95% CI = 1.45-3.09), respectively. Those who used marijuana and other drugs also had higher odds (2.44, 95% CI = 1.58-3.77) of suicidal thoughts than non-users of any illicit drug. However, among users of any illicit drug, no difference was found among users of marijuana only, marijuana and other illicit drugs, and other illicit drugs only. Among marijuana users, marijuana use frequency was a significant correlate of suicidal thoughts only among those with MDE. Health and mental health (MH) service providers should pay close attention to the potential reciprocal effects of marijuana and other illicit drug use and MDE and suicidal thoughts among late middle-aged and older adults.

A Twitter-based survey on marijuana concentrate use.

PubMed

Daniulaityte, Raminta; Zatreh, Mussa Y; Lamy, Francois R; Nahhas, Ramzi W; Martins, Silvia S; Sheth, Amit; Carlson, Robert G

2018-06-01

The purpose of this paper is to analyze characteristics of marijuana concentrate users, describe patterns and reasons of use, and identify factors associated with daily use of concentrates among U.S.-based cannabis users recruited via a Twitter-based online survey. An anonymous Web-based survey was conducted in June 2017 with 687 U.S.-based cannabis users recruited via Twitter-based ads. The survey included questions about state of residence, socio-demographic characteristics, and cannabis use including marijuana concentrates. Multiple logistic regression analyses were conducted to identify characteristics associated with lifetime and daily use of marijuana concentrates. Almost 60% of respondents were male, 86% were white, and the mean age was 43.0 years. About 48% reported marijuana concentrate use. After adjusting for multiple testing, significant predictors of concentrate use included: living in "recreational" (AOR = 2.04; adj. p = .042) or "medical, less restrictive" (AOR = 1.74; adj. p = .030) states, being younger (AOR = 0.97, adj. p = .008), and daily herbal cannabis use (AOR = 2.57, adj. p = .008). Out of 329 marijuana concentrate users, about 13% (n = 44) reported daily/near daily use. Significant predictors of daily concentrate use included: living in recreational states (AOR = 3.59, adj. p = .020) and using concentrates for therapeutic purposes (AOR = 4.34, adj. p = .020). Living in states with more liberal marijuana policies is associated with greater likelihood of marijuana concentrate use and with more frequent use. Characteristics of daily users, in particular, patterns of therapeutic use warrant further research with community-recruited samples. Copyright © 2018 Elsevier B.V. All rights reserved.

Association between marijuana exposure and pulmonary function over 20 years.

PubMed

Pletcher, Mark J; Vittinghoff, Eric; Kalhan, Ravi; Richman, Joshua; Safford, Monika; Sidney, Stephen; Lin, Feng; Kertesz, Stefan

2012-01-11

Marijuana smoke contains many of the same constituents as tobacco smoke, but whether it has similar adverse effects on pulmonary function is unclear. To analyze associations between marijuana (both current and lifetime exposure) and pulmonary function. The Coronary Artery Risk Development in Young Adults (CARDIA) study, a longitudinal study collecting repeated measurements of pulmonary function and smoking over 20 years (March 26, 1985-August 19, 2006) in a cohort of 5115 men and women in 4 US cities. Mixed linear modeling was used to account for individual age-based trajectories of pulmonary function and other covariates including tobacco use, which was analyzed in parallel as a positive control. Lifetime exposure to marijuana joints was expressed in joint-years, with 1 joint-year of exposure equivalent to smoking 365 joints or filled pipe bowls. Forced expiratory volume in the first second of expiration (FEV(1)) and forced vital capacity (FVC). Marijuana exposure was nearly as common as tobacco exposure but was mostly light (median, 2-3 episodes per month). Tobacco exposure, both current and lifetime, was linearly associated with lower FEV(1) and FVC. In contrast, the association between marijuana exposure and pulmonary function was nonlinear (P < .001): at low levels of exposure, FEV(1) increased by 13 mL/joint-year (95% CI, 6.4 to 20; P < .001) and FVC by 20 mL/joint-year (95% CI, 12 to 27; P < .001), but at higher levels of exposure, these associations leveled or even reversed. The slope for FEV(1) was -2.2 mL/joint-year (95% CI, -4.6 to 0.3; P = .08) at more than 10 joint-years and -3.2 mL per marijuana smoking episode/mo (95% CI, -5.8 to -0.6; P = .02) at more than 20 episodes/mo. With very heavy marijuana use, the net association with FEV(1) was not significantly different from baseline, and the net association with FVC remained significantly greater than baseline (eg, at 20 joint-years, 76 mL [95% CI, 34 to 117]; P < .001). Occasional and low cumulative

How and Where Young Adults Obtain Marijuana. The NSDUH Report. Issue 20

ERIC Educational Resources Information Center

Substance Abuse and Mental Health Services Administration, 2006

2006-01-01

The National Survey on Drug Use and Health (NSDUH) asks persons aged 12 or older about their use of marijuana or hashish in the past year, including their frequency of use. This report focuses on how and where past year marijuana users aged 18 to 25 obtained their most recently used marijuana. Findings include estimates from the combined 2002,…

Reasons for Marijuana Use Among Young Adults and Long-Term Associations With Marijuana Use and Problems

PubMed Central

Patrick, Megan E.; Bray, Bethany C.; Berglund, Patricia A.

2016-01-01

Objective: This study examines reasons for marijuana use among young adults age 19/20 in the United States and the extent to which patterns of reasons are associated with marijuana use and problems 15 years later. Method: The national Monitoring the Future study provided data on marijuana users at age 19/20 who were also surveyed at age 35 (n = 2,288; 50% women; 83% White). Latent class analysis was used to identify distinct patterns of reasons for marijuana use, which were then used as predictors of later marijuana use and problems. Results: Five latent classes described the following patterns of reasons for marijuana use at age 19/20: Experimental, Get High + Relax, Typical, Typical + Escape, and Coping + Drug Use. Highest risk for later marijuana use and problems was found for people with Coping + Drug Use and Get High + Relax reasons in young adulthood; those with Experimental reasons were at lowest risk for later use or problems. Conclusions: Coping and getting high emerged as strong predictors of later marijuana use and problems. Results support the predictive value of self-reported reasons for using marijuana among young adults. PMID:27797689

Brain glucose metabolism in chronic marijuana users at baseline and during marijuana intoxication.

PubMed

Volkow, N D; Gillespie, H; Mullani, N; Tancredi, L; Grant, C; Valentine, A; Hollister, L

1996-05-31

Despite the widespread abuse of marijuana, knowledge about its effects in the human brain is limited. Brain glucose metabolism with and without delta 9 tetrahydrocannabinol (THC) (main psychoactive component of marijuana) was evaluated in eight normal subjects and eight chronic marijuana abusers with positron emission tomography. At baseline, marijuana abusers showed lower relative cerebellar metabolism than normal subjects. THC increased relative cerebellar metabolism in all subjects, but only abusers showed increases in orbitofrontal cortex, prefrontal cortex, and basal ganglia. Cerebellar metabolism during THC intoxication was significantly correlated with the subjective sense of intoxication. The decreased cerebellar metabolism in marijuana abusers at baseline could account for the motor deficits previously reported in these subjects. The activation of orbitofrontal cortex and basal ganglia by THC in the abusers but not in the normal subjects could underlie one of the mechanisms leading to the drive and the compulsion to self-administer the drug observed in addicted individuals.

Medical Marijuana Legalization and Co-use in Adult Cigarette Smokers.

PubMed

Wang, Julie B; Cataldo, Janine K

2016-03-01

We examined effects of long-term medical marijuana legalization on cigarette co-use in a sample of adults. We conducted secondary analysis using data from the 2014 US Tobacco Attitudes and Beliefs Survey, which consisted of cigarette smokers, aged ≥ 45 years (N = 506). Participants were categorized by their state residence, where medical marijuana was (1) illegal, (2) legalized < 10 years, and (3) legalized ≥ 10 years. The Web-based survey assessed participants' marijuana use, beliefs and attitudes on marijuana, and nicotine dependence using Fagerstrom Tolerance for Nicotine Dependence (FTND) and Hooked on Nicotine Checklist (HONC) scores. In cigarette smokers aged ≥ 45 years, long-term legalization of medical marijuana was associated with stable positive increases in marijuana use prevalence (ever in a lifetime) (p = .005) and frequency (number of days in past 30 days) (unadjusted p = .005; adjusted p = .08). Those who reported marijuana co-use had greater FTND and HONC scores after adjusting for covariates (p = .05). These preliminary findings warrant further examination of the potential impact of long-term legalization of medical marijuana on greater cigarette and marijuana co-use in adults and higher nicotine dependence among co-users at the population level.

Adolescents' attitudes toward antimarijuana ads, usage intentions, and actual marijuana usage.

PubMed

Alvaro, Eusebio M; Crano, William D; Siegel, Jason T; Hohman, Zachary; Johnson, Ian; Nakawaki, Brandon

2013-12-01

The association of adolescents' appraisals of the antimarijuana TV ads used in the National Youth Antidrug Media Campaign with future marijuana use was investigated. The 12- to 18-year-old respondents (N = 2,993) were first classified as users, resolute nonusers, or vulnerable nonusers (Crano, Siegel, Alvaro, Lac, & Hemovich, 2008). Usage status and the covariates of gender, age, and attitudes toward marijuana were used to predict attitudes toward the ads (Aad) in the first phase of a multilevel linear analysis. All covariates were significantly associated with Aad, as was usage status: Resolute nonusers evaluated the ads significantly more positively than vulnerable nonusers and users (all ps < .001), who did not differ. In the second phase, the covariates along with Aad and respondents' usage status predicted intentions and actual usage 1 year after initial measurement. The lagged analysis disclosed negative associations between Aad and usage intentions and between Aad and actual marijuana use (both ps < .05); however, this association held only for users (p < .01), not vulnerable or resolute nonusers. Users who reported more positive attitudes toward the ads were less likely to report intention to use marijuana and to continue marijuana use at 1-year follow-up. These findings may inform designers of persuasion-based prevention campaigns, guiding preimplementation efforts in the design of ads that targeted groups find appealing and thus, influential. PsycINFO Database Record (c) 2013 APA, all rights reserved.

The Impact of Recreational Marijuana Legislation in Washington, DC on Marijuana Use Cognitions.

PubMed

Clarke, Paige; Dodge, Tonya; Stock, Michelle L

2018-04-13

There is little published research that tests the effect of recreational marijuana legislation on risk-related cognitions and how individuals respond immediately after legislative approval. The objective was to test whether learning about the passage of Initiative 71, a voter referendum that legalized recreational use of marijuana in the District of Columbia, would lead individuals to adopt more favorable marijuana cognitions than they had before the Initiative was passed. Undergraduate students (N = 402) completed two web-based questionnaires in 2014. The first questionnaire was completed prior to the referendum vote and the follow-up questionnaire was completed after voters approved Initiative 71. Attitudes, perceived norms, intentions, prototypes, and willingness were measured at time 1 and time 2. Study hypotheses were tested using repeated-measures analysis of covariance. Results showed that attitudes, intentions, perceived norms, and willingness to use marijuana were more favorable after Initiative 71 was passed. However, the increase in attitudes and willingness was moderated by past experience with marijuana whereby the increases were statistically significant only among those with the least experience. The increase in perceived norms was also moderated by past experience whereby increases were statistically significant among those who were moderate or heavy users. The passage of Initiative 71 had no effect on favorable prototypes. Conclusion/Importance: Legalization may have the unintended outcome of leading to more favorable intentions to use marijuana and might lead abstainers or experimental users to become more frequent users of marijuana via more positive attitudes and willingness towards marijuana use.

Marijuana Use and Cardiovascular Disease.

PubMed

Franz, Christopher A; Frishman, William H

2016-01-01

Marijuana is currently the most used illicit substance in the world. With the current trend of decriminalization and legalization of marijuana in the US, physicians in the US will encounter more patients using marijuana recreationally over a diverse range of ages and health states. Therefore, it is relevant to review marijuana's effects on human cardiovascular physiology and disease. Compared with placebo, marijuana cigarettes cause increases in heart rate, supine systolic and diastolic blood pressures, and forearm blood flow via increased sympathetic nervous system activity. These actions increase myocardial oxygen demand to a degree that they can decrease the time to exercise-induced angina in patients with a history of stable angina. In addition, marijuana has been associated with triggering myocardial infarctions (MIs) in young male patients. Smoking marijuana has been shown to increase the risk of MI onset by a factor of 4.8 for the 60 minutes after marijuana consumption, and to increase the annual risk of MI in the daily cannabis user from 1.5% to 3% per year. Human and animal models suggest that this effect may be due to coronary arterial vasospasm. However, longitudinal studies have indicated that marijuana use may not have a significant effect on long-term mortality. While further research is required to definitively determine the impact of marijuana on cardiovascular disease, it is reasonable to recommend against recreational marijuana use, especially in individuals with a history of coronary artery disorders.

College student marijuana involvement: Perceptions, use, and consequences across 11 college campuses.

PubMed

Pearson, Matthew R; Liese, Bruce S; Dvorak, Robert D

2017-03-01

Marijuana is currently the most commonly used illicit drug in the United States, and with the movement toward legalization of recreational marijuana, the country faces numerous issues regarding policy, prevention, and treatment of marijuana use. The present study examines the prevalence of marijuana use and consequences and compares users and non-users on a wide range of other marijuana-related constructs among college students across 11 universities. Participants included 8141 college students recruited from the psychology department participant pools of 11 universities throughout the US, including four major regions of the US (West, South, Midwest, Northeast) and states with varying policies regarding the legality of marijuana use. We observed marijuana use rates similar to representative samples of young adults and college students (i.e., 53.3% lifetime marijuana users, 26.2% past month marijuana users). About 1 in 10 past month marijuana users experienced no consequences from their use, whereas nearly 1 in 10 experienced 19 or more consequences. Lifetime marijuana users had more positive perceptions of marijuana compared to non-users on a wide-range of marijuana-related constructs. We report descriptive statistics on a wide range of marijuana-related variables. We hope that these data provide a useful baseline prior to increased legalization of recreational marijuana use. Multi-site studies like this one are needed to study the risky and protective factors for problematic marijuana use. These findings can inform interventions and public policy. Copyright © 2016 Elsevier Ltd. All rights reserved.

College Student Marijuana Involvement: Perceptions, Use, and Consequences across 11 College Campuses

PubMed Central

Pearson, Matthew R; Liese, Bruce S; Dvorak, Robert D

2016-01-01

Background Marijuana is currently the most commonly used illicit drug in the United States, and with the movement toward legalization of recreational marijuana, the country faces numerous issues regarding policy, prevention, and treatment of marijuana use. The present study examines the prevalence of marijuana use and consequences and compare users and non-users on a wide range of other marijuana-related constructs among college students across 11 universities. Method Participants included 8,141 college students recruited from the psychology department participant pools of 11 universities throughout the US, including four major regions of the US (West, South, Midwest, Northeast) and states with varying policies regarding the legality of marijuana use. Results We observed marijuana use rates similar to representative samples of young adults and college students (i.e., 53.3% lifetime marijuana users, 26.2% past month marijuana users). About 1 in 10 past month marijuana users experienced no consequences from their use, whereas nearly 1 in 10 experienced 19 or more consequences. Lifetime marijuana users had more positive perceptions of marijuana compared to non-users on a wide-range of marijuana-related constructs. Conclusions We report descriptive statistics on a wide range of marijuana-related variables. We hope that these data provide a useful baseline prior to increased legalization of recreational marijuana use. Multi-site studies like this one are needed to study the risky and protective factors for problematic marijuana use. These findings can inform interventions and public policy. PMID:27894029

Marijuana Exposure Among Children Younger Than Six Years in the United States.

PubMed

Onders, Bridget; Casavant, Marcel J; Spiller, Henry A; Chounthirath, Thiphalak; Smith, Gary A

2016-05-01

This study investigates marijuana exposures among children <6 years old in the United States using data from the National Poison Data System. From 2000 through 2013, there were 1969 marijuana exposures among children <6 years old and an exposure rate of 5.90 per million children. The mean age of an exposed child was 1.81 years (median = 1.58 years). The majority of the children were exposed through ingestion (75.0%), and 18.5% of exposures required admission to a health care facility. The rate of marijuana exposure was significantly (2.82 times) higher in states where its use was legalized prior to 2000 compared with states where its use is not legal. Because more states are likely to pass legislation legalizing medical and recreational use of marijuana, increased efforts to establish child-focused safety requirements regarding packaging of commercially sold marijuana products are needed to help prevent more children from being exposed to this schedule I substance. © The Author(s) 2015.

Oral health assessment for users of marijuana and cocaine/crack substances.

PubMed

Sordi, Mariane Beatriz; Massochin, Rachel Captzan; Camargo, Alessandra Rodrigues de; Lemos, Tadeu; Munhoz, Etiene de Andrade

2017-12-18

The objective of this study was to assess the oral health status of users of illicit drugs such as marijuana and cocaine/crack and compare it with individuals not using these chemical substances. Questionnaires were applied to 35 illicit drugs users to gather information on demographic status, general health, and use of drugs. Then, a clinical assessment of the oral health condition was performed to collect data on decayed, missing and filled teeth (DMFT) index, salivary flow rate (SFR), and mucosal lesions. The control group was composed of 35 non-illicit drug users. In the experimental group, 91.43% were males, 80% were smokers, and 42.85% were alcoholics. Cocaine was the most common drug used (77.15%), followed by marijuana (68.6%), and crack (51.4%). The average DMFT index was 9.8 and the SFR was reduced in 60% of subjects. Mucosal alterations were detected, but no potentially malignant disorders or oral cancer were diagnosed. Compared to control group, significantly higher values for gender (40%, p = 0.0001), smoking (22.86%) and heavy drinking (5.7%) habits (p = 0.0001), SFR (31.4%; p = 0.0308), and oral lesions (p = 0.0488) were found for the experimental group, although significantly higher values were found in the control group for DMFT index (p = 0.0148). It can be concluded that the use of illicit drugs contributed to an increased prevalence of oral mucosa lesions. In addition, a decline on SFR and a reduced DMFT index was observed for illicit drug users.

Medical Marijuana Legalization and Co-use in Adult Cigarette Smokers

PubMed Central

Wang, Julie B.; Cataldo, Janine K.

2016-01-01

Objectives We examined effects of long-term medical marijuana legalization on cigarette co-use in a sample of adults. Methods We conducted secondary analysis using data from the 2014 US Tobacco Attitudes and Beliefs Survey, which consisted of cigarette smokers, aged ≥ 45 years (N = 506). Participants were categorized by their state residence, where medical marijuana was (1) illegal, (2) legalized < 10 years, and (3) legalized ≥ 10 years. The Web-based survey assessed participants’ marijuana use, beliefs and attitudes on marijuana, and nicotine dependence using Fagerstrom Tolerance for Nicotine Dependence (FTND) and Hooked on Nicotine Checklist (HONC) scores. Results In cigarette smokers aged ≥ 45 years, long-term legalization of medical marijuana was associated with stable positive increases in marijuana use prevalence (ever in a lifetime) (p = .005) and frequency (number of days in past 30 days) (unadjusted p = .005; adjusted p = .08). Those who reported marijuana co-use had greater FTND and HONC scores after adjusting for covariates (p = .05). Conclusions These preliminary findings warrant further examination of the potential impact of long-term legalization of medical marijuana on greater cigarette and marijuana co-use in adults and higher nicotine dependence among co-users at the population level. PMID:26931752

Chronic Offenders: A Life-Course Analysis of Marijuana Users

ERIC Educational Resources Information Center

Ragan, Daniel T.; Beaver, Kevin M.

2010-01-01

Marijuana is the most widely used illegal drug, and the use of marijuana has been linked to a wide array of maladaptive outcomes. As a result, there is great interest in identifying the factors that are associated with the use of marijuana and with desistance from marijuana. The current study employed a life-course framework to examine the factors…

Adult work commitment, financial stability, and social environment as related to trajectories of marijuana use beginning in adolescence.

PubMed

Brook, Judith S; Lee, Jung Yeon; Finch, Stephen J; Seltzer, Nathan; Brook, David W

2013-01-01

The objective of this study is to examine trajectories of marijuana use among African Americans and Puerto Ricans from adolescence to adulthood, with attention paid to work commitment, financial stability, drug use, and violence. Participants (N = 816) completed in-class questionnaires as students in the East Harlem area of New York City at the first wave and provided follow-up data at 4 additional points in time (mean ages = 14, 19, 24, 29, and 32 years). Among 816 participants, there were 60% females, 52% African American, and 48% Puerto Ricans. The chronic marijuana user trajectory group compared with the none or low, increasing, and/or moderate marijuana user trajectory group was associated with negative aspects of work commitment, financial stability, and the social environment. The chronic marijuana user group was similar to the increasing marijuana user group on work commitment and financial stability. These results suggest that treating marijuana use in late adolescence may reduce difficulty in the assumption of adult roles. Because chronic marijuana users experienced the most adverse effects in each of the domains, they require more intense clinical intervention than moderate marijuana users.

Pediatric marijuana exposures in a medical marijuana state.

PubMed

Wang, George Sam; Roosevelt, Genie; Heard, Kennon

2013-07-01

An increasing number of states are decriminalizing the use of medical marijuana, and the effect on the pediatric population has not been evaluated. To compare the proportion of marijuana ingestions by young children who sought care at a children's hospital in Colorado before and after modification of drug enforcement laws in October 2009 regarding medical marijuana possession. Retrospective cohort study from January 1, 2005, through December 31, 2011. Tertiary-care children's hospital emergency department in Colorado. A total of 1378 patients younger than 12 years evaluated for unintentional ingestions: 790 patients before September 30, 2009, and 588 patients after October 1, 2009. Marijuana ingestion. Marijuana exposure visits, marijuana source, symptoms, and patient disposition. The proportion of ingestion visits in patients younger than 12 years (age range, 8 months to 12 years)that were related to marijuana exposure increased after September 30, 2009, from 0 of 790 (0%; 95% CI, 0%-0.6%) to 14 of 588 (2.4%; 95% CI, 1.4%-4.0%) (P < .001). Nine patients had lethargy, 1 had ataxia, and 1 had respiratory insufficiency. Eight patients were admitted, 2 to the intensive care unit. Eight of the 14 cases involved medical marijuana, and 7 of these exposures were from food products. We found a new appearance of unintentional marijuana ingestions by young children after modification of drug enforcement laws for marijuana possession in Colorado. The consequences of unintentional marijuana exposure in children should be part of the ongoing debate on legalizing marijuana.

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.

Marijuana use patterns among patients with inflammatory bowel disease.

PubMed

Ravikoff Allegretti, Jessica; Courtwright, Andrew; Lucci, Matthew; Korzenik, Joshua R; Levine, Jonathan

2013-12-01

The prevalence and perceived effectiveness of marijuana use has not been well studied in inflammatory bowel disease (IBD) despite increasing legal permission for its use in Crohn's disease. Health care providers have little guidance about the IBD symptoms that may improve with marijuana use. The aim of this study was to assess the prevalence, sociodemographic characteristics, and perceived benefits of marijuana use among patients with IBD. Prospective cohort survey study of marijuana use patterns in patients with IBD at an academic medical center. A total of 292 patients completed the survey (response rate = 94%); 12.3% of patients were active marijuana users, 39.0% were past users, and 48.6% were never users. Among current and past users, 16.4% of patients used marijuana for disease symptoms, the majority of whom felt that marijuana was "very helpful" for relief of abdominal pain, nausea, and diarrhea. On multivariate analysis, age and chronic abdominal pain were associated with current marijuana use (odds ratio [OR], 0.93; 95% confidence interval [CI], 0.89-0.97; P < 0.001 and OR, 3.5; 95% CI, 1.24-9.82; P = 0.02). Age and chronic abdominal pain were also multivariate predictors of medicinal use of marijuana (OR, 0.93; 95% CI, 0.89-0.97; P < 0.001 and OR, 4.7; 95% CI, 1.8-12.2; P = 0.001). Half of the never users expressed an interest in using marijuana for abdominal pain, were it legally available. A significant number of patients with IBD currently use marijuana. Most patients find it very helpful for symptom control, including patients with ulcerative colitis, who are currently excluded from medical marijuana laws. Clinical trials are needed to determine marijuana's potential as an IBD therapy and to guide prescribing decisions.

Support for Marijuana Legalization and Predictors of Intentions to Use Marijuana More Often in Response to Legalization Among U.S. Young Adults.

PubMed

Cohn, Amy M; Johnson, Amanda L; Rose, Shyanika W; Rath, Jessica M; Villanti, Andrea C

2017-01-28

As of 2015, more than half of U.S. states have legalized, medicalized, or decriminalized marijuana. This study examined the prevalence and correlates of support for marijuana legalization in a national sample of young adults and the intention to use marijuana more frequently if it were legalized. Data were from Wave 7 (weighted N = 3532) of the Truth Initiative Young Adult Cohort, a national sample of men and women aged 18-34. We assessed demographics, past 30-day substance (alcohol, tobacco, marijuana, other drug use), depression and anxiety, social smoking, marijuana harm perceptions (relative to cigarettes), and state-level marijuana policies as correlates of support for marijuana legalization and intentions to use marijuana more often if it were legalized. Multivariable models of correlates of support for legalization and intentions to use marijuana were conducted separately for the full sample and for nonmarijuana users. Weighted estimates showed that 39% of the full sample and 9% of nonmarijuana users supported marijuana legalization. Multivariable models showed that lower marijuana harm perceptions and lifetime and past 30-day tobacco use were common predictors of support for marijuana legalization and intentions to use marijuana among non-users of marijuana. Conclusions/Importance: Over a third of the sample supported marijuana legalization. Tobacco use and perceptions that marijuana is less harmful than cigarettes were robust risk correlates of support for marijuana legalization and intentions to use more frequently among nonusers. Public health campaigns should target these factors to deter marijuana-related harm in susceptible young adults.

Marijuana use and serum testosterone concentrations among U.S. males.

PubMed

Thistle, J E; Graubard, B I; Braunlin, M; Vesper, H; Trabert, B; Cook, M B; McGlynn, K A

2017-07-01

Marijuana has been reported to have several effects on the male reproductive system. Marijuana has previously been linked to reduced adult testosterone, however, a study in Denmark reported increased testosterone concentrations among marijuana users. This study was performed to estimate the effect of marijuana use on testosterone in U.S. males. Data on serum testosterone, marijuana use, and covariates for 1577 men from the 2011-2012 U.S. National Health and Nutrition Examination Survey (NHANES) were analyzed. Information on marijuana use was collected by a self-administered computer-assisted questionnaire. Serum testosterone was determined using isotope dilution liquid chromatography tandem mass spectrometry. The effects of marijuana use on serum testosterone concentrations were examined by frequency, duration, and recency of use. Adjusted means and 95% confidence intervals (CI) of serum testosterone across levels of marijuana use were estimated using multiple linear regression weighted by the survey weights. The majority (66.2%) of the weighted study population reported ever using marijuana with 26.6% reporting current marijuana use. There was no difference in serum testosterone between ever users (adjusted mean = 3.69 ng/mL, 95% CI: 3.46, 3.93) and never users (adjusted mean = 3.70 ng/mL, 95% CI: 3.45, 3.98) upon multivariable analysis. However, serum testosterone was inversely associated with time since last regular use of marijuana (p-value for trend = 0.02). When restricted to men aged 18-29 years, this relationship strengthened (p-value for trend <0.01), and serum testosterone was also inversely associated with time since last use (p-value for trend <0.01), indicating that recency of use, and not duration or frequency, had the strongest relationship with testosterone levels. Serum testosterone concentrations were higher in men with more recent marijuana use. Studies are needed to determine the extent to which circulating testosterone concentrations

Characterizing substance use and mental health profiles of cigar, blunt, and non-blunt marijuana users from the National Survey of Drug Use and Health.

PubMed

Cohn, Amy; Johnson, Amanda; Ehlke, Sarah; Villanti, Andrea C

2016-03-01

Smoking marijuana in a cigar (blunt use) is gaining popularity in the U.S. Research suggests that blunt users differ from exclusive cigar or marijuana users on a variety of demographic and substance use factors. Misreporting of blunts and cigars is also common, particularly among young people, and may lead to inaccurate prevalence estimates. To determine subtype differences, this study investigated the prevalence and demographic, mental health, and substance use correlates of four mutually-exclusive groups of blunt, cigar, and marijuana past 30-day users (cigar-only, blunt-only, non-blunt marijuana, or dual cigar-blunt). Data were analyzed from the 2013 National Survey of Drug Use and Health. In weighted multinomial logistic regression models, respondents who were younger, Black, and who had used tobacco, alcohol, or other drugs in the past 30-days had the highest odds of reporting blunt-only or dual cigar-blunt use. Those reporting blunt-only and dual cigar-blunt use also endorsed a greater number of marijuana and alcohol use disorder symptoms compared to those reporting cigar-only and non-blunt marijuana use. Lower marijuana risk perceptions were associated with increased odds of marijuana use with or without blunts. Major depressive episode was uniquely associated with non-blunt marijuana use. With respect to misclassifiers, respondents who reported past 30-day blunt use but not past 30-day marijuana use were younger, Black, female, and had lower education and income. Those who report blunt-only and dual cigar-blunt use showed the most severe risk profiles. Communicating health consequences and risks of blunt use should be directed toward specific subgroups. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

From Medical to Recreational Marijuana Sales: Marijuana Outlets and Crime in an Era of Changing Marijuana Legislation.

PubMed

Freisthler, Bridget; Gaidus, Andrew; Tam, Christina; Ponicki, William R; Gruenewald, Paul J

2017-06-01

A movement from medical to recreational marijuana use allows for a larger base of potential users who have easier access to marijuana, because they do not have to visit a physician before using marijuana. This study examines whether changes in the density of marijuana outlets were related to violent, property, and marijuana-specific crimes in Denver, CO during a time in which marijuana outlets began selling marijuana for recreational, and not just medical, use. We collected data on locations of crimes, marijuana outlets and covariates for 481 Census block groups over 34 months (N = 16,354 space-time units). A Bayesian Poisson space-time model assessed statistical relationships between independent measures and crime counts within "local" Census block groups. We examined spatial "lag" effects to assess whether crimes in Census block groups adjacent to locations of outlets were also affected. Independent of the effects of covariates, densities of marijuana outlets were unrelated to property and violent crimes in local areas. However, the density of marijuana outlets in spatially adjacent areas was positively related to property crime in spatially adjacent areas over time. Further, the density of marijuana outlets in local and spatially adjacent blocks groups was related to higher rates of marijuana-specific crime. This study suggests that the effects of the availability of marijuana outlets on crime do not necessarily occur within the specific areas within which these outlets are located, but may occur in adjacent areas. Thus studies assessing the effects of these outlets in local areas alone may risk underestimating their true effects.

Racial differences in marijuana-users' risk of arrest in the United States.

PubMed

Ramchand, Rajeev; Pacula, Rosalie Liccardo; Iguchi, Martin Y

2006-10-01

A recent study of arrest data show that African Americans are 2.5 times more likely to be arrested for marijuana possession offences than Whites, even though general prevalence estimates show that they are no more likely to be using. The current study investigates the purchase patterns of marijuana users from the 2002 National Survey on Drug Use and Health (NSDUH) to evaluate whether differences in purchasing behaviors exist across racial groups. Although in general people who purchase marijuana are more likely to buy in private settings and from someone they know, this analysis shows that African Americans are statistically more likely to engage in risky purchasing behaviors that increase their likelihood of arrest. Using trivariate probit regression with demographic, drug use, and drug market covariates, analyses reveal that African Americans are nearly twice as likely to buy outdoors (0.31 versus 0.14), three times more likely to buy from a stranger (0.30 versus 0.09), and significantly more likely to buy away from their homes (0.61 versus 0.48). These results provide an additional explanation for the differential in arrest rates between African Americans and Whites.

Marijuana Use by Adolescents and Young Adults with Inflammatory Bowel Disease.

PubMed

Hoffenberg, Edward J; McWilliams, Shannon K; Mikulich-Gilbertson, Susan K; Murphy, Brittany V; Lagueux, Megan; Robbins, Kristen; Hoffenberg, Analice S; de Zoeten, Edwin; Hopfer, Christian J

2018-04-16

To evaluate marijuana use by adolescents and young adults with inflammatory bowel disease (IBD). This descriptive cross-sectional study of patients seen between December 2015 through June 2017 at Children's Hospital Colorado for IBD enrolled patients 13-23 years of age, independent of marijuana use status. Information obtained consisted of chart review, electronic and interview self-report, and serum cannabinoid levels. Marijuana ever-users were compared with never-users for clinical characteristics and perceptions of risk with use; users provided information on routes, patterns, motivations, and perceived benefits and problems with use. Of 99 participants, ever-use was endorsed by 32% (32 of 99) and daily or almost daily use by 9% (9 of 99). Older age was the only characteristic related to endorsing marijuana use. Twenty-nine ever-users completed all questionnaires. After adjusting for age, users were 10.7 times more likely to perceive low risk of harm with regular use (P < .001). At least 1 medical reason for use was endorsed by 57% (17 of 30), most commonly for relief of physical pain (53%, 16 of 30) (2 did not complete all questionnaires). Problems from use were identified by 37% (11 of 30), most commonly craving/strong urge to use. Most common route of use was smoking (83%) followed by edibles (50%), dabbing (40%), and vaping (30%). Marijuana use by adolescents and young adults with IBD is common and perceived as beneficial. Guidelines for screening, testing, and counseling of marijuana use should be developed for patients with IBD. Copyright © 2018 Elsevier Inc. All rights reserved.

An Internet survey of marijuana and hot shower use in adults with cyclic vomiting syndrome (CVS).

PubMed

Venkatesan, Thangam; Sengupta, Jyotirmoy; Lodhi, Atena; Schroeder, Abigail; Adams, Kathleen; Hogan, Walter J; Wang, Yanzhi; Andrews, Christopher; Storr, Martin

2014-08-01

Cyclic vomiting syndrome (CVS) is a chronic disorder characterized by episodic nausea and vomiting. A large proportion of patients use marijuana to control their symptoms. Several case reports implicate marijuana as a cause of intractable vomiting with compulsive hot water bathing considered pathognomonic of "cannabinoid hyperemesis." We sought to examine the relationship between marijuana use and CVS. Patients >18 years of age diagnosed by a health care provider were invited to participate in an anonymous internet-based survey. A total of 514 patients participated and 437 completed questions about marijuana use. Mean age was 34 ± 12 years with patients being predominantly female (63%), Caucasian (92%) and from the USA (82%). Nineteen percent never used marijuana and 81% did. Fifty-four percent used marijuana for health issues and 43% for recreational purposes. Users stated that it improved nausea, appetite, general well-being, stress levels and vomiting. Users were more likely to be male and have an associated anxiety disorder. Sixty-seven percent of patients reported taking hot showers/baths for symptom relief, and this was associated with marijuana use. (OR 2.54, CI 1.50-4.31, P = 0.0006). Eighty-one percent of patients with CVS who completed an internet survey reported frequent use of marijuana. With marijuana use, patients noted the greatest improvement with stress levels, appetite and nausea. Marijuana users were more likely to be male and have associated anxiety. Hot showers were not pathognomonic of marijuana use though they were more likely to be associated with its use.

Profiles of Patients Who Use Marijuana for Inflammatory Bowel Disease.

PubMed

Kerlin, Ann Marie; Long, Millie; Kappelman, Michael; Martin, Christopher; Sandler, Robert S

2018-06-01

Marijuana is legal in a number of states for indications that include inflammatory bowel diseases (IBD), and patients are interested in its potential benefits. We aimed to describe the legal use of marijuana in individuals with IBD in the USA who participate within the CCFA Partners internet-based cohort. A total of 2357 participants who lived in states where prescription or recreational marijuana was legal, were offered the opportunity to complete a survey on marijuana use and IBD symptoms including perceived benefits of therapy. Bivariate statistics and logistic regression models were used to determine factors associated with marijuana use. Surveys were completed by 1666 participants (71%) with only 214 (12.8%) indicating they had asked their medical doctor about its use and 73 actually using prescribed marijuana (4.4%). Within the respondent group (N = 1666), 234 participants lived where both medical and recreational marijuana is legal and 49 (20.9%) reported recreational marijuana use specifically for IBD. Users reported positive benefits (80.7%), but users also reported more depression, anxiety, pain interference, and lower social satisfaction than non-users. Those prescribed marijuana reported more active disease, and more use of steroids, narcotics, and zolpidem. Few IBD patients consulted their medical doctors about marijuana use or used prescription marijuana. Where recreational marijuana was available, usage rates were higher. Users reported benefits but also more IBD symptoms, depression, anxiety, and pain. Marijuana use may be higher in patients with IBD symptoms not well treated by conventional medical approaches.

A population-based case-control study of marijuana use and head and neck squamous cell carcinoma.

PubMed

Liang, Caihua; McClean, Michael D; Marsit, Carmen; Christensen, Brock; Peters, Edward; Nelson, Heather H; Kelsey, Karl T

2009-08-01

Cannabinoids, constituents of marijuana smoke, have been recognized to have potential antitumor properties. However, the epidemiologic evidence addressing the relationship between marijuana use and the induction of head and neck squamous cell carcinoma (HNSCC) is inconsistent and conflicting. Cases (n = 434) were patients with incident HNSCC disease from nine medical facilities in the Greater Boston, MA area between December 1999 and December 2003. Controls (n = 547) were frequency matched to cases on age (+/-3 years), gender, and town of residence, randomly selected from Massachusetts town books. A questionnaire was adopted to collect information on lifetime marijuana use (decade-specific exposures) and associations evaluated using unconditional logistic regression. After adjusting for potential confounders (including smoking and alcohol drinking), 10 to 20 years of marijuana use was associated with a significantly reduced risk of HNSCC [odds ratio (OR)(10-<20 years versus never users), 0.38; 95% confidence interval (CI), 0.22-0.67]. Among marijuana users moderate weekly use was associated with reduced risk (OR(0.5-<1.5 times versus <0.5 time), 0.52; 95% CI, 0.32-0.85). The magnitude of reduced risk was more pronounced for those who started use at an older age (OR(15-<20 years versus never users), 0.53; 95% CI, 0.30-0.95; OR(> or =20 years versus never users), 0.39; 95% CI, 0.17-0.90; P(trend) < 0.001). These inverse associations did not depend on human papillomavirus 16 antibody status. However, for the subjects who have the same level of smoking or alcohol drinking, we observed attenuated risk of HNSCC among those who use marijuana compared with those who do not. Our study suggests that moderate marijuana use is associated with reduced risk of HNSCC.

Marijuana and lung diseases.

PubMed

Joshi, Manish; Joshi, Anita; Bartter, Thaddeus

2014-03-01

Cannabis sativa (marijuana) is used throughout the world, and its use is increasing. In much of the world, marijuana is illicit. While inhalation of smoke generated by igniting dried components of the plant is the most common way marijuana is used, there is concern over potential adverse lung effects. The purpose of this review is to highlight recent studies that explore the impact upon the respiratory system of inhaling marijuana smoke. Smoking marijuana is associated with chronic bronchitis symptoms and large airway inflammation. Occasional use of marijuana with low cumulative use is not a risk factor for the development of chronic obstructive pulmonary disease. The heavy use of marijuana alone may lead to airflow obstruction. The immuno-histopathologic and epidemiologic evidence in marijuana users suggests biological plausibility of marijuana smoking as a risk for the development of lung cancer; at present, it has been difficult to conclusively link marijuana smoking and cancer development. There is unequivocal evidence that habitual or regular marijuana smoking is not harmless. A caution against regular heavy marijuana usage is prudent. The medicinal use of marijuana is likely not harmful to lungs in low cumulative doses, but the dose limit needs to be defined. Recreational use is not the same as medicinal use and should be discouraged.

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

Current and former marijuana use: preliminary findings of a longitudinal study of effects on IQ in young adults

PubMed Central

Fried, Peter; Watkinson, Barbara; James, Deborah; Gray, Robert

2002-01-01

Background Assessing marijuana's impact on intelligence quotient (IQ) has been hampered by a lack of evaluation of subjects before they begin to use this substance. Using data from a group of young people whom we have been following since birth, we examined IQ scores before, during and after cessation of regular marijuana use to determine any impact of the drug on this measure of cognitive function. Methods We determined marijuana use for seventy 17- to 20-year-olds through self-reporting and urinalysis. IQ difference scores were calculated by subtracting each person's IQ score at 9–12 years (before initiation of drug use) from his or her score at 17–20 years. We then compared the difference in IQ scores of current heavy users (at least 5 joints per week), current light users (less than 5 joints per week), former users (who had not smoked regularly for at least 3 months) and non-users (who never smoked more than once per week and no smoking in the past two weeks). Results Current marijuana use was significantly correlated (p < 0.05) in a dose- related fashion with a decline in IQ over the ages studied. The comparison of the IQ difference scores showed an average decrease of 4.1 points in current heavy users (p < 0.05) compared to gains in IQ points for light current users (5.8), former users (3.5) and non-users (2.6). Interpretation Current marijuana use had a negative effect on global IQ score only in subjects who smoked 5 or more joints per week. A negative effect was not observed among subjects who had previously been heavy users but were no longer using the substance. We conclude that marijuana does not have a long-term negative impact on global intelligence. Whether the absence of a residual marijuana effect would also be evident in more specific cognitive domains such as memory and attention remains to be ascertained. PMID:11949984

Current and former marijuana use: preliminary findings of a longitudinal study of effects on IQ in young adults.

PubMed

Fried, Peter; Watkinson, Barbara; James, Deborah; Gray, Robert

2002-04-02

Assessing marijuana's impact on intelligence quotient (IQ) has been hampered by a lack of evaluation of subjects before they begin to use this substance. Using data from a group of young people whom we have been following since birth, we examined IQ scores before, during and after cessation of regular marijuana use to determine any impact of the drug on this measure of cognitive function. We determined marijuana use for seventy 17- to 20-year-olds through self-reporting and urinalysis. IQ difference scores were calculated by subtracting each person's IQ score at 9-12 years (before initiation of drug use) from his or her score at 17-20 years. We then compared the difference in IQ scores of current heavy users (at least 5 joints per week), current light users (less than 5 joints per week), former users (who had not smoked regularly for at least 3 months) and non-users (who never smoked more than once per week and no smoking in the past two weeks). Current marijuana use was significantly correlated (p < 0.05) in a dose-related fashion with a decline in IQ over the ages studied. The comparison of the IQ difference scores showed an average decrease of 4.1 points in current heavy users (p < 0.05) compared to gains in IQ points for light current users (5.8), former users (3.5) and non-users (2.6). Current marijuana use had a negative effect on global IQ score only in subjects who smoked 5 or more joints per week. A negative effect was not observed among subjects who had previously been heavy users but were no longer using the substance. We conclude that marijuana does not have a long-term negative impact on global intelligence. Whether the absence of a residual marijuana effect would also be evident in more specific cognitive domains such as memory and attention remains to be ascertained.

Marijuana Use and Self-reported Quality of Eyesight.

PubMed

Akano, Obinna F

2017-05-01

There is increasing use of marijuana among young adults and more states in the United States are legalizing medical marijuana use. A number of studies have revealed both the beneficial and harmful effects of marijuana to the human system. Despite some beneficial effects, studies have shown marijuana to have a lot of deleterious effects on the visual system, which subsequently reduces the quality of eyesight. The aim of this study was to investigate if heavy marijuana smoking is associated with a poor quality of eyesight compared with light/no use of marijuana. The National Longitudinal Survey of Youths (NLSY79), a nationally representative sample of 12,686 young men and women surveyed in 1979 to 2010 was used for this study. The quality of eyesight of 1304 heavy marijuana users was compared with 1304 respondents with light or no marijuana use. The t test, multivariate and weighted logistic regression were used in the data analysis. There was no statistically significant difference in the self-reported quality of eyesight among heavy marijuana smokers compared with youths who never used marijuana or are light marijuana users. Among heavy marijuana smokers, males and high school graduates have decreased odds of reporting a poor quality of eyesight, whereas blacks have increased odds of reporting a poor quality of eyesight. The self-reported quality of eyesight among marijuana users can aid clinicians and other health practitioners facilitate the development of sex-, racial/ethnic-, and educational level-informed prevention and early intervention programs and also help characterize public opinions regarding cannabis, which are particularly relevant given the ongoing debate concerning the medicalization and legalization of cannabis in the United States.

Marijuana.

PubMed

Ammerman, Seth

2014-04-01

Marijuana use in pediatric populations remains an ongoing concern, and marijuana use by adolescents had known medical, psychological, and cognitive side effects. Marijuana alters brain development and has detrimental effects on brain structure and function in ways that are incompletely understood at this point in time. Furthermore, marijuana smoke contains tar and other harmful chemicals, so marijuana cannot be recommended by physicians. At this time, no studies suggest a benefit of marijuana use by children and adolescents. In the context of limited but clear evidence showing harm or potential harm from marijuana use by adolescents, any recommendations for medical marijuana use by adolescents are based on research studies with adults and on anecdotal evidence. Criminal prosecution for marijuana possession adversely affects hundreds of thousands of youth yearly in the United States, particularly minority youth. Current evidence does not support a focus on punishment for youth who use marijuana. Rather, drug education and treatment programs should be encouraged to better help youth who are experimenting with or are dependent on marijuana. Decriminalization of recreational use of marijuana by adults has not led to an increase in youth use rates of recreational marijuana. Thus, decriminalization may be a reasonable alternative to outright criminalization, as long as it is coupled with drug education and treatment programs. The effect of outright legalization of adult recreational use of marijuana on youth use is unknown.

Exposure to and Content of Marijuana Product Reviews.

PubMed

Cavazos-Rehg, Patricia A; Krauss, Melissa J; Sowles, Shaina J; Murphy, Gabrielle M; Bierut, Laura J

2018-02-01

Many individuals now seek out product reviews in order to make an informed decision prior to making a purchase. In this study, we investigate consumers' exposure to and content within product reviews about marijuana because of their potential to shape marijuana purchasing decisions. The terms "weed review," "marijuana review," and "cannabis review" were searched on YouTube on June 10-11, 2015; the team viewed and coded the content of 83 product review videos about marijuana. In addition, we surveyed young adult (18-34 years old) current (past month) marijuana users (n = 742) from across the USA online to assess exposure to product reviews about marijuana and associations with socio-demographic characteristics and marijuana use behaviors. In our content analysis of videos, we observed that the reviewers tended to consume marijuana during the video and often shared personal, favorable experiences towards the marijuana they ingested (e.g., became as high as possible or experienced positive effects on physical and mental health). Most videos normalized marijuana use and could be easily accessed by underage youth. About one third (34%) of the survey participants viewed/sought a product review about marijuana in the past 30 days. In a multivariable logistic regression model, living in a state where recreational use is legal or using multiple forms of marijuana was associated with increased odds of viewing/seeking marijuana reviews. Prevention messages should counter product reviews about marijuana that tend to normalize and promote marijuana use given that they are more readily viewed by individuals who are increasingly susceptible to marijuana's potential harms.

Brain imaging study of the acute effects of Delta9-tetrahydrocannabinol (THC) on attention and motor coordination in regular users of marijuana.

PubMed

Weinstein, Aviv; Brickner, Orit; Lerman, Hedva; Greemland, Mazal; Bloch, Miki; Lester, Hava; Chisin, Roland; Mechoulam, Raphael; Bar-Hamburger, Rachel; Freedman, Nanette; Even-Sapir, Einat

2008-01-01

Twelve regular users of marijuana underwent two positron emission tomography (PET) scans using [18F] Fluorodeoxyglucose (FDG), one while subject to the effects of 17 mg THC, the other without THC. In both sessions, a virtual reality maze task was performed during the FDG uptake period. When subject to the effects of 17 mg THC, regular marijuana smokers hit the walls more often on the virtual maze task than without THC. Compared to results without THC, 17 mg THC increased brain metabolism during task performance in areas that are associated with motor coordination and attention in the middle and medial frontal cortices and anterior cingulate, and reduced metabolism in areas that are related to visual integration of motion in the occipital lobes. These findings suggest that in regular marijuana users, the immediate effects of marijuana may impact on cognitive-motor skills and brain mechanisms that modulate coordinated movement and driving.

Medical marijuana use among adolescents in substance abuse treatment.

PubMed

Salomonsen-Sautel, Stacy; Sakai, Joseph T; Thurstone, Christian; Corley, Robin; Hopfer, Christian

2012-07-01

To assess the prevalence and frequency of medical marijuana diversion and use among adolescents in substance abuse treatment and to identify factors related to their medical marijuana use. This study calculated the prevalence and frequency of diverted medical marijuana use among adolescents (n = 164), ages 14-18 years (mean age = 16.09, SD = 1.12), in substance abuse treatment in the Denver metropolitan area. Bivariate and multivariate analyses were completed to determine factors related to adolescents' use of medical marijuana. Approximately 74% of the adolescents had used someone else's medical marijuana, and they reported using diverted medical marijuana a median of 50 times. After adjusting for gender and race/ethnicity, adolescents who used medical marijuana had an earlier age of regular marijuana use, more marijuana abuse and dependence symptoms, and more conduct disorder symptoms compared with those who did not use medical marijuana. Medical marijuana use among adolescent patients in substance abuse treatment is very common, implying substantial diversion from registered users. These results support the need for policy changes that protect against diversion of medical marijuana and reduce adolescent access to diverted medical marijuana. Future studies should examine patterns of medical marijuana diversion and use in general population adolescents. Copyright © 2012 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

Marijuana and actual driving performance

DOT National Transportation Integrated Search

1993-11-01

This report concerns the effects of marijuana smoking on actual driving performance. It presents the results of one pilot and three actual driving studies. The pilot study's major purpose was to establish the THC dose current marijuana users smoke to...

The role of marijuana use etiquette in avoiding targeted police enforcement

PubMed Central

REAM, GEOFFREY L.; JOHNSON, BRUCE D.; DUNLAP, ELOISE; BENOIT, ELLEN

2012-01-01

Internationally, where marijuana is illegal, users follow etiquette rules that prevent negative consequences of use. In this study, adherence to etiquette is hypothesized to reduce likelihood of marijuana-related police stop/search and arrest. Ethnographers administered group surveys to a diverse, purposive sample of 462 marijuana-using peer groups in several areas of New York City. Findings indicated that lack of etiquette was associated with dramatically higher likelihood of police stop/search or arrest only for users who were Black, male, and/or recruited from Harlem/South Bronx. If these users followed a few identified etiquette rules, their risk of police stop/search or arrest was comparable to that of other users. Implications are that etiquette represents an intentional conscientiousness about marijuana use. Groups that are specially targeted for anti-marijuana enforcement can remediate that heightened risk by following marijuana etiquette. PMID:23155303

Recent Marijuana Use and Associations With Exhaled Nitric Oxide and Pulmonary Function in Adults in the United States.

PubMed

Papatheodorou, Stefania I; Buettner, Hannah; Rice, Mary B; Mittleman, Murray A

2016-06-01

The medical and recreational use of marijuana is now legal in some parts of the United States; the health effects are unknown. We aimed to evaluate associations between recent marijuana use and exhaled nitric oxide (eNO) and pulmonary function. We performed a cross-sectional study of 10,327 US adults participating in the National Health and Nutrition Examination Survey in the years 2007 to 2012. We examined associations between marijuana use and eNO, FEV1, FVC, the FEV1/FVC ratio, and forced expiratory flow (midexpiratory phase) (FEF25%-75%) by weighted linear regression. In the study population, there were 4,797 never users, 4,084 past marijuana users, 555 participants who used marijuana 5 to 30 days before the examination, and 891 participants who used marijuana 0 to 4 days before the examination. Current marijuana use in the past 4 days was associated with 13% lower eNO (95% CI, -18% to 8%). FVC was higher in past users (75 mL; 95% CI, 38-112) and current users in the past 5 to 30 days (159 mL; 95% CI, 80-237) and in users within 0 to 4 days of the examination (204 mL; 95% CI, 139-270) compared with never users. All associations remained unchanged and statistically significant in sensitivity analyses excluding current and past tobacco users. Current marijuana use was associated with lower levels of eNO and higher FVC. The lower eNO in marijuana smokers suggests that short-term exposure to marijuana may, like tobacco, acutely affect the pulmonary vascular endothelium and impair airflow through the small airways. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

Quantifying cannabis: A field study of marijuana quantity estimation.

PubMed

Prince, Mark A; Conner, Bradley T; Pearson, Matthew R

2018-06-01

The assessment of marijuana use quantity poses unique challenges. These challenges have limited research efforts on quantity assessments. However, quantity estimates are critical to detecting associations between marijuana use and outcomes. We examined accuracy of marijuana users' estimations of quantities of marijuana they prepared to ingest and predictors of both how much was prepared for a single dose and the degree of (in)accuracy of participants' estimates. We recruited a sample of 128 regular-to-heavy marijuana users for a field study wherein they prepared and estimated quantities of marijuana flower in a joint or a bowl as well as marijuana concentrate using a dab tool. The vast majority of participants overestimated the quantity of marijuana that they used in their preparations. We failed to find robust predictors of estimation accuracy. Self-reported quantity estimates are inaccurate, which has implications for studying the link between quantity and marijuana use outcomes. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

SOCIAL ANXIETY DISORDER AND MARIJUANA USE PROBLEMS: THE MEDIATING ROLE OF MARIJUANA EFFECT EXPECTANCIES

PubMed Central

Buckner, Julia D.; Schmidt, Norman B.

2009-01-01

Background: Individuals with social anxiety disorder (SAD) appear particularly vulnerable to marijuana-related problems. Yet, mechanisms underlying this association are unclear. Methods: This study examined the role of marijuana effect expectancies in the relation between SAD and marijuana problems among 107 marijuana users (43.0% female), 26.2% of whom met Diagnostic and Statistical Manual for Mental Disorders—Fourth Edition criteria for SAD. Anxiety and mood disorders were determined during clinical interviews using the Anxiety Disorders Interview Schedule—IV-L (ADIS-IV). Results: Analyses (including sex, marijuana use frequency, major depressive disorder, and other anxiety disorders) suggest that SAD was the only disorder significantly associated with past 3-month marijuana problems. Compared to those without SAD, individuals with SAD were more likely to endorse the following marijuana expectancies: cognitive/behavioral impairment and global negative expectancies. Importantly, these expectancies mediated the relations between SAD status and marijuana problems. Conclusions: These data support the contention that SAD is uniquely related to marijuana problems and provide insight into mechanisms underlying this vulnerability. PMID:19373871

Whither RDS? An investigation of Respondent Driven Sampling as a method of recruiting mainstream marijuana users

PubMed Central

2010-01-01

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

Further Validation of a Marijuana Purchase Task

PubMed Central

Aston, Elizabeth R.; Metrik, Jane; MacKillop, James

2015-01-01

Background A valid measure of the relative economic value of marijuana is needed to characterize individual variation in the drug’s reinforcing value and inform evolving national marijuana policy. Relative drug value (demand) can be measured via purchase tasks, and demand for alcohol and cigarettes has been associated with craving, dependence, and treatment response. This study examined marijuana demand with a marijuana purchase task (MPT). Methods The 22-item self-report MPT was administered to 99 frequent marijuana users (37.4% female, 71.5% marijuana use days, 15.2% cannabis dependent). Results Pearson correlations indicated a negative relationship between intensity (free consumption) and age of initiation of regular use (r=−0.34, p<0.001), and positive associations with use days (r=0.26, p<0.05) and subjective craving (r=0.43, p<0.001). Omax (maximum expenditure) was positively associated with use days (r=0.29, p<0.01) and subjective craving (r=0.27, p<0.01). Income was not associated with demand. An exponential demand model provided an excellent fit to the data across users (R2=0.99). Group comparisons based on presence or absence of DSM-IV cannabis dependence symptoms revealed that users with any dependence symptoms showed significantly higher intensity of demand and more inelastic demand, reflecting greater insensitivity to price increases. Conclusions These results provide support for construct validity of the MPT, indicating its sensitivity to marijuana demand as a function of increasing cost, and its ability to differentiate between users with and without dependence symptoms. The MPT may denote abuse liability and is a valuable addition to the behavioral economic literature. Potential applications to marijuana pricing and tax policy are discussed. PMID:26002377

Lessons learned after three years of legalized, recreational marijuana: The Colorado experience.

PubMed

Ghosh, Tista S; Vigil, Daniel I; Maffey, Ali; Tolliver, Rickey; Van Dyke, Mike; Kattari, Leonardo; Krug, Heather; Reed, Jack K; Wolk, Larry

2017-11-01

In November 2012 Colorado voters approved legalized recreational marijuana. On January 1, 2014 Colorado became the first state to allow legal sales of non-medical marijuana for adults over the age of 21. Since that time, the state has been monitoring potential impacts on population health. In this paper we present lessons learned in the first three years following legal sales of recreational marijuana. These lessons pertain to health behaviors and health outcomes, as well as to health policy issues. Our intent is to share these lessons with other states as they face the prospect of recreational marijuana legalization. Copyright © 2017 Elsevier Inc. All rights reserved.

A Case Series of Marijuana Exposures in Pediatric Patients Less than 5 Years of Age

ERIC Educational Resources Information Center

Wang, George Sam; Narang, Sandeep K.; Wells, Kathryn; Chuang, Ryan

2011-01-01

Objective: In Colorado, there has been a large increase in medical marijuana dispensaries and licenses for the use of medical marijuana over the past year. This is a retrospective case series of marijuana exposures that have presented to the emergency department (ED) in children less than 5 years of age. Methods: We performed a retrospective chart…

Marijuana and tobacco use and co-use among African Americans: results from the 2013, National Survey on Drug Use and Health.

PubMed

Montgomery, LaTrice

2015-12-01

Although studies have identified an increased likelihood of marijuana and tobacco co-use among African Americans as compared to other racial groups, few studies have specifically examined the prevalence and substance use characteristics of co-users among African Americans in a national survey. The current secondary analysis examined the prevalence rates and substance use characteristics (e.g., marijuana dependence) of 2024 African American past month marijuana and tobacco users and co-users participating in the 2013 National Survey on Drug Use and Health. Findings revealed that 18.5%, 53.8% and 27.7% of African Americans smoked marijuana only, tobacco only and marijuana and tobacco in the past 30days, respectively. Relative to participants who smoked marijuana only, African Americans who smoked marijuana and tobacco were more likely to be marijuana dependent in the past year and report more days of marijuana use in the past month. Further, relative to participants who smoked tobacco only, African Americans who smoked marijuana and tobacco were less likely to be dependent on nicotine, reported fewer days of cigarette use in the past month, and began smoking cigarettes, cigars and marijuana at a younger age, but were more likely to be marijuana dependent in the past year and reported more days of cigar use in the past month. Marijuana and tobacco co-use is a significant public health problem, especially among African Americans. Additional research on effective prevention and treatment interventions for African Americans who smoke marijuana and tobacco is warranted. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

PubMed

Fairman, Brian J; Furr-Holden, C Debra; Johnson, Renee M

2018-05-17

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

The Association between Early Conduct Problems and Early Marijuana Use in College Students

ERIC Educational Resources Information Center

Falls, Benjamin J.; Wish, Eric D.; Garnier, Laura M.; Caldeira, Kimberly M.; O'Grady, Kevin E.; Vincent, Kathryn B.; Arria, Amelia M.

2011-01-01

Early conduct problems have been linked to early marijuana use in adolescence. The present study examines this association in a sample of 1,076 college students that was divided into three groups: (1) early marijuana users (began marijuana use prior to age 15; N = 126), (2) late marijuana users (began marijuana use at or after age 15; N = 607),…

Driving Under the Influence of Alcohol, Marijuana, and Alcohol and Marijuana Combined Among Persons Aged 16-25 Years - United States, 2002-2014.

PubMed

Azofeifa, Alejandro; Mattson, Margaret E; Lyerla, Rob

2015-12-11

Motor vehicle accidents are the leading cause of death among youths and young adults aged 16-25 years in the United States (1). The prevalence of drinking and driving among high school students aged 16-19 years has declined by 54%, from 22.3% in 1991 to 10.3% in 2011 (2). However, the prevalence of weekend nighttime driving under the influence of marijuana (based on biochemical assays) among drivers aged ≥16 years has increased by 48%, from 8.6% in 2007 to 12.6% in 2013-2014 (3). Use of marijuana alone and in combination with alcohol has been shown to impair driving abilities (4-9). This report provides the most recent self-reported national estimates of driving under the influence of alcohol, marijuana, and alcohol and marijuana combined among persons aged 16-25 years, using data from the Substance Abuse and Mental Health Services Administration (SAMHSA) National Survey on Drug Use and Health (NSDUH) from 2002-2014. Prevalence data on driving under the influence of both substances were examined for two age groups (16-20 years and 21-25 years) and by sex and race/ethnicity. During 2002-2014, the prevalence of driving under the influence of alcohol alone significantly declined by 59% among persons aged 16-20 years (from 16.2% in 2002 to 6.6% in 2014; p<0.001) and 38% among persons 21-25 years (from 29.1% in 2002 to 18.1% in 2014; p<0.001). In addition, the prevalence of driving under the influence of alcohol and marijuana combined significantly declined by 39%, from 2.3% in 2002 to 1.4% in 2014 (p<0.001) among persons aged 16-20 years and from 3.1% in 2002 to 1.9% in 2014 (p<0.001) among persons aged 21-25 years. The prevalence of driving under the influence of marijuana alone declined 18%, from 3.8% in 2002 to 3.1% in 2014 (p = 0.05) only among persons aged 16-20 years. Effective public safety interventions,* such as minimum legal drinking age laws, prohibition of driving with any alcohol level >0 for persons aged <21 years, targeted mass media campaigns

Regular Marijuana Users May Have Impaired Brain Reward Centers

MedlinePlus

... use and use disorders increase in states with medical marijuana laws College students at increased risk for smoking ... dripping” 2016 New analysis highlights patterns of adult medical marijuana use Journal issue addresses nonmedical use of prescription ...

The at-risk adolescent marijuana nonuser: expanding the standard distinction.

PubMed

Crano, William D; Siegel, Jason T; Alvaro, Eusebio M; Lac, Andrew; Hemovich, Vanessa

2008-06-01

This research expands the user/nonuser dichotomy commonly used in research on marijuana. By conceptualizing nonusers as homogeneous, vital nuances in susceptibility to risk and protective factors may be overlooked. Research operations tested the predictive validity of a brief measure that divided nonusers into resolute and vulnerable subcategories; determined whether variables that distinguished nonusers and users were more informative when a tripartite classification was used; and with an eye on future prevention, examined variables on which resolute nonusers were similar to vulnerable nonusers or users, and on which they differed from both. A nationally representative sample of respondents (N = 2,111; ages 12-16 years) from the National Survey of Parents and Youth was used in this secondary analysis. Panel data gathered yearly over four rounds included information on intentions and use of marijuana and other illicit substances, along with social, demographic, intrapersonal, and parental variables. The three groups differed significantly on associates' marijuana use, participants' approval of others' use, and cigarette and alcohol use. Resolute nonusers differed from vulnerable nonusers and users alike on religiosity, delinquency (self and friends'), refusal strength, sensation seeking, parental monitoring and warmth, and adult supervision. Results support the utility of distinguishing vulnerable from resolute nonusers, counsel against considering nonusers as a homogeneous group, and provide insight into variables that might prove useful in future prevention efforts.

Frequency and Risk of Marijuana Use among Substance-Using Health Care Patients in Colorado with and without Access to State Legalized Medical Marijuana.

PubMed

Richmond, Melissa K; Pampel, Fred C; Rivera, Laura S; Broderick, Kerryann B; Reimann, Brie; Fischer, Leigh

2015-01-01

With increasing use of state legalized medical marijuana across the country, health care providers need accurate information on patterns of marijuana and other substance use for patients with access to medical marijuana. This study compared frequency and severity of marijuana use, and use of other substances, for patients with and without state legal access to medical marijuana. Data were collected from 2,030 patients who screened positive for marijuana use when seeking health care services in a large, urban safety-net medical center. Patients were screened as part of a federally funded screening, brief intervention, and referral to treatment (SBIRT) initiative. Patients were asked at screening whether they had a state-issued medical marijuana card and about risky use of tobacco, alcohol, and other illicit substances. A total of 17.4% of marijuana users had a medical marijuana card. Patients with cards had higher frequency of marijuana use and were more likely to screen at moderate than low or high risk from marijuana use. Patients with cards also had lower use of other substances than patients without cards. Findings can inform health care providers of both the specific risks of frequent, long-term use and the more limited risks of other substance use faced by legal medical marijuana users.

A Behavioral Economic Approach to Assessing Demand for Marijuana

PubMed Central

Collins, R. Lorraine; Vincent, Paula C.; Yu, Jihnhee; Liu, Liu; Epstein, Leonard H.

2014-01-01

In the U.S., marijuana is the most commonly used illicit drug. Its prevalence is growing, particularly among young adults. Behavioral economic indices of the relative reinforcing efficacy (RRE) of substances have been used to examine the appeal of licit (e.g., alcohol) and illicit (e.g., heroin) drugs. The present study is the first to use an experimental, simulated purchasing task to examine the RRE of marijuana. Young-adult (M age = 21.64 years) recreational marijuana users (N = 59) completed a computerized marijuana purchasing task designed to generate demand curves and the related RRE indices (e.g., intensity of demand - purchases at lowest price; Omax - max. spent on marijuana; Pmax - price at which marijuana expenditure is max). Participants “purchased” high-grade marijuana across 16 escalating prices that ranged from $0/free to $160/joint. They also provided 2-weeks of real-time, ecological momentary assessment reports on their marijuana use. The purchasing task generated multiple RRE indices. Consistent with research on other substances, the demand for marijuana was inelastic at lower prices but became elastic at higher prices, suggesting that increases in the price of marijuana could lessen its use. In regression analyses, the intensity of demand, Omax and Pmax, and elasticity each accounted for significant variance in real-time marijuana use. These results provide support for the validity of a simulated marijuana purchasing task to examine its reinforcing efficacy. This study highlights the value of applying a behavioral economic framework to young-adult marijuana use and has implications for prevention, treatment, and policies to regulate marijuana use. PMID:24467370

Early onset marijuana use is associated with learning inefficiencies.

PubMed

Schuster, Randi Melissa; Hoeppner, Susanne S; Evins, A Eden; Gilman, Jodi M

2016-05-01

Verbal memory difficulties are the most widely reported and persistent cognitive deficit associated with early onset marijuana use. Yet, it is not known what memory stages are most impaired in those with early marijuana use. Forty-eight young adults, aged 18-25, who used marijuana at least once per week and 48 matched nonusing controls (CON) completed the California Verbal Learning Test, Second Edition (CVLT-II). Marijuana users were stratified by age of initial use: early onset users (EMJ), who started using marijuana at or before age 16 (n = 27), and late onset marijuana user group (LMJ), who started using marijuana after age 16 (n = 21). Outcome variables included trial immediate recall, total learning, clustering strategies (semantic clustering, serial clustering, ratio of semantic to serial clustering, and total number of strategies used), delayed recall, and percent retention. Learning improved with repetition, with no group effect on the learning slope. EMJ learned fewer words overall than LMJ or CON. There was no difference between LMJ and CON in total number of words learned. Reduced overall learning mediated the effect on reduced delayed recall among EMJ, but not CON or LMJ. Learning improved with greater use of semantic versus serial encoding, but this did not vary between groups. EMJ was not related to delayed recall after adjusting for encoding. Young adults reporting early onset marijuana use had learning weaknesses, which accounted for the association between early onset marijuana use and delayed recall. No amnestic effect of marijuana use was observed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Early Onset Marijuana Use Is Associated with Learning Inefficiencies

PubMed Central

Schuster, Randi Melissa; Hoeppner, Susanne S.; Evins, A. Eden; Gilman, Jodi M.

2016-01-01

Objective Verbal memory difficulties are the most widely reported and persistent cognitive deficit associated with early-onset marijuana use. Yet, it is not known what memory stages are most impaired in those with early marijuana use. Method Forty-eight young adults, aged 18–25, who used marijuana at least once per week and 48 matched non-using controls (CON) completed the California Verbal Learning Test, Second Edition (CVLT-II). Marijuana users were stratified by age of initial use: ‘early onset’ users (EMJ), who started using marijuana at or before age 16 (n = 27), and ‘late onset’ marijuana user group (LMJ), who started using marijuana after age 16 (n = 21). Outcome variables included trial immediate recall, total learning, clustering strategies (semantic clustering, serial clustering, ratio of semantic to serial clustering, and total number of strategies used), delayed recall, and percent retention. Results Learning improved with repetition, with no group effect on the learning slope. EMJ learned fewer words overall than LMJ or CON. There was no difference between LMJ and CON in total number of words learned. Reduced overall learning mediated the effect on reduced delayed recall among EMJ, but not CON or LMJ. Learning improved with greater use of semantic versus serial encoding, but this did not vary between groups. EMJ was not related to delayed recall after adjusting for encoding. Conclusions Young adults reporting early onset marijuana use had learning weaknesses, which accounted for the association between early onset marijuana use and delayed recall. No amnestic effect of marijuana use was observed. PMID:26986749

Health Risk Behaviors With Synthetic Cannabinoids Versus Marijuana.

PubMed

Clayton, Heather B; Lowry, Richard; Ashley, Carmen; Wolkin, Amy; Grant, Althea M

2017-04-01

Data are limited on the behavioral risk correlates of synthetic cannabinoid use. The purpose of this study was to compare the behavioral risk correlates of synthetic cannabinoid use with those among marijuana users. Data from the 2015 Youth Risk Behavior Survey, a cross-sectional survey conducted in a nationally representative sample of students in grades 9 through 12 ( N = 15 624), were used to examine the association between self-reported type of marijuana use (ie, never use of marijuana and synthetic cannabinoids, ever use of marijuana only, and ever use of synthetic cannabinoids) and self-report of 36 risk behaviors across 4 domains: substance use, injury/violence, mental health, and sexual health. Multivariable models were used to calculate adjusted prevalence ratios. Students who ever used synthetic cannabinoids had a significantly greater likelihood of engaging in each of the behaviors in the substance use and sexual risk domains compared with students who ever used marijuana only. Students who ever used synthetic cannabinoids were more likely than students who ever used marijuana only to have used marijuana before age 13 years, to have used marijuana ≥1 times during the past 30 days, and to have used marijuana ≥20 times during the past 30 days. Several injury/violence behaviors were more prevalent among students who ever used synthetic cannabinoids compared with students who ever used marijuana only. Health professionals and school-based substance use prevention programs should include strategies focused on the prevention of both synthetic cannabinoids and marijuana. Copyright © 2017 by the American Academy of Pediatrics.

Long-term effects of marijuana use on the brain

PubMed Central

Filbey, Francesca M.; Aslan, Sina; Calhoun, Vince D.; Spence, Jeffrey S.; Damaraju, Eswar; Caprihan, Arvind; Segall, Judith

2014-01-01

Questions surrounding the effects of chronic marijuana use on brain structure continue to increase. To date, however, findings remain inconclusive. In this comprehensive study that aimed to characterize brain alterations associated with chronic marijuana use, we measured gray matter (GM) volume via structural MRI across the whole brain by using voxel-based morphology, synchrony among abnormal GM regions during resting state via functional connectivity MRI, and white matter integrity (i.e., structural connectivity) between the abnormal GM regions via diffusion tensor imaging in 48 marijuana users and 62 age- and sex-matched nonusing controls. The results showed that compared with controls, marijuana users had significantly less bilateral orbitofrontal gyri volume, higher functional connectivity in the orbitofrontal cortex (OFC) network, and higher structural connectivity in tracts that innervate the OFC (forceps minor) as measured by fractional anisotropy (FA). Increased OFC functional connectivity in marijuana users was associated with earlier age of onset. Lastly, a quadratic trend was observed suggesting that the FA of the forceps minor tract initially increased following regular marijuana use but decreased with protracted regular use. This pattern may indicate differential effects of initial and chronic marijuana use that may reflect complex neuroadaptive processes in response to marijuana use. Despite the observed age of onset effects, longitudinal studies are needed to determine causality of these effects. PMID:25385625

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…

A behavioral economic approach to assessing demand for marijuana.

PubMed

Collins, R Lorraine; Vincent, Paula C; Yu, Jihnhee; Liu, Liu; Epstein, Leonard H

2014-06-01

In the United States, marijuana is the most commonly used illicit drug. Its prevalence is growing, particularly among young adults. Behavioral economic indices of the relative reinforcing efficacy (RRE) of substances have been used to examine the appeal of licit (e.g., alcohol) and illicit (e.g., heroin) drugs. The present study is the first to use an experimental, simulated purchasing task to examine the RRE of marijuana. Young-adult (M age = 21.64 years) recreational marijuana users (N = 59) completed a computerized marijuana purchasing task designed to generate demand curves and the related RRE indices (e.g., intensity of demand-purchases at lowest price; Omax-max. spent on marijuana; Pmax-price at which marijuana expenditure is max). Participants "purchased" high-grade marijuana across 16 escalating prices that ranged from $0/free to $160/joint. They also provided 2 weeks of real-time, ecological momentary assessment reports on their marijuana use. The purchasing task generated multiple RRE indices. Consistent with research on other substances, the demand for marijuana was inelastic at lower prices but became elastic at higher prices, suggesting that increases in the price of marijuana could lessen its use. In regression analyses, the intensity of demand, Omax, and Pmax, and elasticity each accounted for significant variance in real-time marijuana use. These results provide support for the validity of a simulated marijuana purchasing task to examine marijuana's reinforcing efficacy. This study highlights the value of applying a behavioral economic framework to young-adult marijuana use and has implications for prevention, treatment, and policies to regulate marijuana use. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Effects of marijuana on visuospatial working memory: an fMRI study in young adults.

PubMed

Smith, Andra M; Longo, Carmelinda A; Fried, Peter A; Hogan, Matthew J; Cameron, Ian

2010-06-01

The effects of marijuana use on visuospatial working memory were investigated in 19-21-year-olds using functional magnetic resonance imaging (fMRI). Participants were members of the Ottawa Prenatal Prospective Study, a longitudinal study that collected a unique body of information on participants from infancy to young adulthood including: prenatal drug history, detailed cognitive/behavioral performance, and current and past drug usage. This information allowed for the measurement of an unprecedented number of potentially confounding drug exposure variables including: prenatal marijuana, nicotine, alcohol, and caffeine exposure and offspring alcohol, marijuana, and nicotine use. Ten marijuana users and 14 nonusing controls performed a visuospatial 2-back task while fMRI blood oxygen level-dependent response was examined. Despite similar task performance, marijuana users had significantly greater activation in the inferior and middle frontal gyri, regions of the brain normally associated with visuospatial working memory. Marijuana users also had greater activation in the right superior temporal gyrus, a region of the brain not typically associated with visuospatial working memory tasks. These results suggest that marijuana use leads to altered neural functioning during visuospatial working memory after controlling for other prenatal and current drug use. This alteration appears to be compensated for by the recruitment of blood flow in additional brain regions. It is possible that this compensation may not be sufficient in more real-life situations where this type of processing is required and thus deficits may be observed. Awareness of these neural physiological effects of marijuana in youth is critical.

How Is Marijuana Vaping Portrayed on YouTube? Content, Features, Popularity and Retransmission of Vaping Marijuana YouTube Videos.

PubMed

Yang, Qinghua; Sangalang, Angeline; Rooney, Molly; Maloney, Erin; Emery, Sherry; Cappella, Joseph N

2018-01-01

The purpose of the study is to investigate how vaping marijuana, a novel but emerging risky health behavior, is portrayed on YouTube, and how the content and features of these YouTube videos influence their popularity and retransmission. A content analysis of vaping marijuana YouTube videos published between July 2014 to June 2015 (n = 214) was conducted. Video genre, valence, promotional and warning arguments, emotional appeals, message sensation value, presence of misinformation and misleading information, and user-generated statistics, including number of views, comments, shares, likes and dislikes, were coded. The results showed that these videos were predominantly pro-marijuana-vaping, with the most frequent videos being user-sharing. The genre and message features influenced the popularity, evaluations, and retransmission of vaping marijuana YouTube videos. Theoretical and practical implications are discussed.

Sexual Risk Behavior and Heavy Drinking Among Weekly Marijuana Users

PubMed Central

Metrik, Jane; Caswell, Amy J.; Magill, Molly; Monti, Peter M.; Kahler, Christopher W.

2016-01-01

Objective: Sexual behavior that incurs increased risk for sexually transmitted infections and HIV incidence is associated with both heavy alcohol and marijuana use. Whereas detrimental effects of alcohol on increased sexual risk have been documented in event-level and laboratory studies, less is known about the combined use of alcohol and marijuana and their relative impact on sexual risk behavior. We examined the degree to which both heavy drinking and marijuana use were associated with condomless sexual intercourse with casual versus main partners in a sample of weekly marijuana smokers. Method: Participants reported substance use and sexual activity using a 60-day Timeline Followback interview method (n = 112). Results: Results of generalized estimating equations indicated that both alcohol and marijuana use were independently associated with greater odds of having sexual intercourse but were not associated with greater odds of unprotected sex with a casual partner. Heavy drinking on a given day was associated with increased odds of having casual protected sex. Using both substances synergistically increased the likelihood of unprotected sex with a main partner. Conclusions: Findings suggest that behaviors posing higher sexual risk (condomless intercourse or sex with casual partners) occur on days when alcohol use exceeds moderate drinking guidelines. Interventions designed to reduce sexual risk behaviors may need to specifically target heavy drinking alone or when used with marijuana. PMID:26751360

The impact of marijuana use on memory in HIV-infected patients: a comprehensive review of the HIV and marijuana literatures

PubMed Central

Skalski, Linda M.; Towe, Sheri L.; Sikkema, Kathleen J.; Meade, Christina S.

2016-01-01

Background The most robust neurocognitive effect of marijuana use is memory impairment. Memory deficits are also high among persons living with HIV/AIDS, and marijuana is the most commonly used drug in this population. Yet research examining neurocognitive outcomes resulting from co-occurring marijuana and HIV is limited. Objective The primary objectives of this comprehensive review are to: (1) examine the literature on memory functioning in HIV-infected individuals; (2) examine the literature on memory functioning in marijuana users; (3) synthesize findings and propose a theoretical framework to guide future research. Method PubMed was searched for English publications 2000–2013. Twenty-two studies met inclusion criteria in the HIV literature, and 23 studies in the marijuana literature. Results Among HIV-infected individuals, memory deficits with medium to large effect sizes were observed. Marijuana users also demonstrated memory problems, but results were less consistent due to the diversity of samples. Conclusion A compensatory hypothesis, based on the cognitive aging literature, is proposed to provide a framework to explore the interaction between marijuana and HIV. There is some evidence that individuals infected with HIV recruit additional brain regions during memory tasks to compensate for HIV-related declines in neurocognitive functioning. Marijuana use causes impairment in similar brain systems, and thus it is hypothesized that the added neural strain of marijuana can exhaust neural resources, resulting in pronounced memory impairment. It will be important to test this hypothesis empirically, and future research priorities are discussed. PMID:27138170

Polytobacco, marijuana, and alcohol use patterns in college students: A latent class analysis

PubMed Central

Haardörfer, Regine; Berg, Carla J.; Lewis, Michael; Payne, Jackelyn; Pillai, Drishti; McDonald, Bennett; Windle, Michael

2016-01-01

Limited research has examined polysubstance use profiles among young adults focusing on the various tobacco products currently available. We examined use patterns of various tobacco products, marijuana, and alcohol using data from the baseline survey of a multiwave longitudinal study of 3418 students aged 18-25 recruited from seven U.S. college campuses. We assessed sociodemographics, individual-level factors (depression; perceptions of harm and addictiveness,), and sociocontextual factors (parental/friend use). We conducted a latent class analysis and multivariable logistic regression to examine correlates of class membership (Abstainers were referent group). Results indicated five classes: Abstainers (26.1% per past 4-month use), Alcohol only users (38.9%), Heavy polytobacco users (7.3%), Light polytobacco users (17.3%), and little cigar and cigarillo (LCC)/hookah/marijuana co-users (10.4%). The most stable was LCC/hookah/marijuana co-users (77.3% classified as such in past 30-day and 4-month timeframes), followed by Heavy polytobacco users (53.2% classified consistently). Relative to Abstainers, Heavy polytobacco users were less likely to be Black and have no friends using alcohol and perceived harm of tobacco and marijuana use lower. Light polytobacco users were older, more likely to have parents using tobacco, and less likely to have friends using tobacco. LCC/hookah/marijuana co-users were older and more likely to have parents using tobacco. Alcohol only users perceived tobacco and marijuana use to be less socially acceptable, were more likely to have parents using alcohol and friends using marijuana, but less likely to have friends using tobacco. These findings may inform substance use prevention and recovery programs by better characterizing polysubstance use patterns. PMID:27074202

La Marihuana: Informacion para los Adolescentes. Revisada (Marijuana: Facts for Teens. Revised).

ERIC Educational Resources Information Center

National Inst. on Drug Abuse (DHHS/PHS), Rockville, MD.

Using a question and answer format, this booklet is designed to inform teens about the dangers of marijuana usage. Inset facts about marijuana and teen perspectives compliment the following topics: (1) What is marijuana? (2) How is marijuana used? (3) How long does marijuana stay in the user's body? (4) How many teens smoke marijuana? (5) Why do…

An epidemiologic review of marijuana and cancer: an update

PubMed Central

Huang, Yu-Hui Jenny; Zhang, Zuo-Feng; Tashkin, Donald P.; Feng, Bingjian; Straif, Kurt; Hashibe, Mia

2014-01-01

Marijuana use is legal in two states and additional states are considering legalization. Approximately 18 million Americans are current marijuana users. There is currently no consensus on whether marijuana use is associated with cancer risk. Our objective is to review the epidemiologic studies on this possible association. We identified 34 epidemiologic studies on upper aerodigestive tract cancers (n=11), lung cancer (n=6), testicular cancer (n=3), childhood cancers (n=6), all cancers (n=1), anal cancer (n=1), penile cancer (n=1), non-Hodgkin's lymphoma (n=2), malignant primary gliomas(n=1), bladder cancer (n=1), and Kaposi's sarcoma (n=1). Studies on head and neck cancer reported increased and decreased risks, possibly because there is no association, or because risks differ by HPV status or geographic differences. The lung cancer studies largely appear not to support an association with marijuana use, possibly because of the smaller amounts of marijuana regularly smoked compared to tobacco. Three testicular cancer case-control studies reported increased risks with marijuana use (summary odds ratios 1.56 (95%CI=1.09-2.23) for higher frequency; 1.50 (95%=1.08-2.09) for ≥10 years). For other cancer sites, there is still insufficient data to make any conclusions. Considering that marijuana use may change due to legalization, well-designed studies on marijuana use and cancer are warranted. PMID:25587109

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

PubMed

Johnson, Renee M; Fairman, Brian; Gilreath, Tamika; Xuan, Ziming; Rothman, Emily F; Parnham, Taylor; Furr-Holden, C Debra M

2015-10-01

The potential for increases in adolescent marijuana use is an important concern given recent changes in marijuana policy. The purpose of this study was to estimate trends in marijuana use from 1999 to 2013 among a national sample of US high school students. We examine changes over time by race/ethnicity and sex. Data are from the National Youth Risk Behavior Survey (YRBS), which involves biennial, school-based surveys that generate nationally representative data about 9th-12th grade students in the United States. Students self-reported sex, race/ethnicity, and marijuana use (i.e., lifetime use, past 30-day use, any use before age 13). We generated national estimates of the prevalence of marijuana use for the time period, and also tested for linear and quadratic trends (n=115,379). The prevalence of lifetime marijuana use decreased modestly from 1999 to 2009 (44% to 37%), and has increased slightly since 2009 (41%). Other marijuana use variables (e.g., past 30-day use) followed a similar pattern over time. The prevalence of past 30-day use from 1999 to 2013 for all groups and both sexes was 22.5%, and it was lowest among Asians and highest among American Indian/Alaska Natives. Although boys have historically had a higher prevalence of marijuana use, results indicate that male-female differences in marijuana use decreased over time. Despite considerable changes in state marijuana policies over the past 15 years, marijuana use among high school students has largely declined. Continued surveillance is needed to assess the impact of policy changes on adolescent marijuana use. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Past 15-Year Trends in Adolescent Marijuana Use: Differences by Race/Ethnicity and Sex

PubMed Central

Johnson, Renee M.; Fairman, Brian; Gilreath, Tamika; Xuan, Ziming; Rothman, Emily F.; Parnham, Taylor; Furr-Holden, C. Debra M.

2015-01-01

Background The potential for increases in adolescent marijuana use is an important concern given recent changes in marijuana policy. The purpose of this study was to estimate trends in marijuana use from 1999-2013 among a national sample of US high school students. We examine changes over time by race/ethnicity and sex. Methods Data are from the National Youth Risk Behavior Survey (YRBS), which involves biennial, school-based surveys that generate nationally-representative data about 9th-12th grade students in the United States. Students self-reported sex, race/ethnicity, and marijuana use (i.e., lifetime use, current use, any use before age 13). We generated national estimates of the prevalence of marijuana use for the time period, and also tested for linear and quadratic trends (n=115,379). Results The prevalence of lifetime marijuana use decreased modestly from 1999 to 2009 (44% to 37%), and has increased slightly since 2009 (41%). Other marijuana use variables (e.g., past 30-day use) followed a similar pattern over time. The prevalence of past 30-day use from 1999-2013 for all groups and both sexes was 22.5%, and it was lowest among Asians and highest among American Indian/Alaska Natives. Although boys have historically had a higher prevalence of marijuana use, results indicate that male-female differences in marijuana use decreased over time. Conclusion Despite considerable changes in state marijuana policies over the past 15 years, marijuana use among high school students has largely declined. Continued surveillance is needed to assess the impact of policy changes on adolescent marijuana use. PMID:26361714

Marijuana protective behavioral strategies as a moderator of the effects of risk/protective factors on marijuana-related outcomes.

PubMed

Bravo, Adrian J; Anthenien, Amber M; Prince, Mark A; Pearson, Matthew R

2017-06-01

Given that both marijuana use and cannabis use disorder peak among college students, it is imperative to determine the factors that may reduce risk of problematic marijuana use and/or the development of cannabis use disorder. From a harm reduction perspective, the present study examined whether the use of marijuana protective behavioral strategies (PBS) buffers or amplifies the effects of several distinct risk and protective factors that have been shown to relate to marijuana-related outcomes (i.e., use frequency and consequences). Specifically, we examined marijuana-PBS use as a moderator of the effects of impulsivity-like traits, marijuana use motives, gender, and marijuana use frequency on marijuana-related outcomes in a large sample of college students (n=2093 past month marijuana users across 11 universities). In all models PBS use was robustly related with use frequency and consequences (i.e., strongly negatively associated with marijuana outcomes). Among interactions, we found: 1) unique significant interactions between specific impulsivity-like traits (i.e., premeditation, perseverance, and sensation seeking) and marijuana-PBS use in predicting marijuana consequences, 2) unique significant interactions between each marijuana use motive and marijuana-PBS use in predicting marijuana use frequency and 3) marijuana-PBS use buffered the risk associated with male gender in predicting both marijuana outcomes. Our results suggest that marijuana-PBS use can buffer risk factors and enhance protective factors among marijuana using college students. Future research is needed to understand context-specific factors and individual-level factors that may make marijuana-PBS use more effective. Copyright © 2017 Elsevier Ltd. All rights reserved.

Longitudinal influence of alcohol and marijuana use on academic performance in college students.

PubMed

Meda, Shashwath A; Gueorguieva, Ralitza V; Pittman, Brian; Rosen, Rivkah R; Aslanzadeh, Farah; Tennen, Howard; Leen, Samantha; Hawkins, Keith; Raskin, Sarah; Wood, Rebecca M; Austad, Carol S; Dager, Alecia; Fallahi, Carolyn; Pearlson, Godfrey D

2017-01-01

Alcohol and marijuana are the two most abused substances in US colleges. However, research on the combined influence (cross sectional or longitudinal) of these substances on academic performance is currently scant. Data were derived from the longitudinal 2-year Brain and Alcohol Research in College Students (BARCS) study including 1142 freshman students who completed monthly marijuana use and alcohol consumption surveys. Subjects were classified into data-driven groups based on their alcohol and marijuana consumption. A linear mixed-model (LMM) was employed using this grouping factor to predict grade point average (GPA), adjusted for a variety of socio-demographic and clinical factors. Three data-driven clusters emerged: 1) No/low users of both, 2) medium-high alcohol/no-low marijuana, and 3) medium-high users of both substances. Individual cluster derivations between consecutive semesters remained stable. No significant interaction between clusters and semester (time) was noted. Post-hoc analysis suggest that at the outset, compared to sober peers, students using moderate to high levels of alcohol and low marijuana demonstrate lower GPAs, but this difference becomes non-significant over time. In contrast, students consuming both substances at moderate-to-high levels score significantly lower at both the outset and across the 2-year investigation period. Our follow-up analysis also indicate that when students curtailed their substance use over time they had significantly higher academic GPA compared to those who remained stable in their substance use patterns over the two year period. Overall, our study validates and extends the current literature by providing important implications of concurrent alcohol and marijuana use on academic achievement in college.

Longitudinal influence of alcohol and marijuana use on academic performance in college students

PubMed Central

Meda, Shashwath A.; Gueorguieva, Ralitza V.; Pittman, Brian; Rosen, Rivkah R.; Aslanzadeh, Farah; Tennen, Howard; Leen, Samantha; Hawkins, Keith; Raskin, Sarah; Wood, Rebecca M.; Austad, Carol S.; Dager, Alecia; Fallahi, Carolyn; Pearlson, Godfrey D.

2017-01-01

Background Alcohol and marijuana are the two most abused substances in US colleges. However, research on the combined influence (cross sectional or longitudinal) of these substances on academic performance is currently scant. Methods Data were derived from the longitudinal 2-year Brain and Alcohol Research in College Students (BARCS) study including 1142 freshman students who completed monthly marijuana use and alcohol consumption surveys. Subjects were classified into data-driven groups based on their alcohol and marijuana consumption. A linear mixed-model (LMM) was employed using this grouping factor to predict grade point average (GPA), adjusted for a variety of socio-demographic and clinical factors. Results Three data-driven clusters emerged: 1) No/low users of both, 2) medium-high alcohol/no-low marijuana, and 3) medium-high users of both substances. Individual cluster derivations between consecutive semesters remained stable. No significant interaction between clusters and semester (time) was noted. Post-hoc analysis suggest that at the outset, compared to sober peers, students using moderate to high levels of alcohol and low marijuana demonstrate lower GPAs, but this difference becomes non-significant over time. In contrast, students consuming both substances at moderate-to-high levels score significantly lower at both the outset and across the 2-year investigation period. Our follow-up analysis also indicate that when students curtailed their substance use over time they had significantly higher academic GPA compared to those who remained stable in their substance use patterns over the two year period. Conclusions Overall, our study validates and extends the current literature by providing important implications of concurrent alcohol and marijuana use on academic achievement in college. PMID:28273162

Maternal Patterns of Marijuana Use and Early Sexual Behavior in Offspring of Teenage Mothers

PubMed Central

Goldschmidt, Lidush; Cornelius, Marie D.

2015-01-01

Teenage mothers use marijuana more frequently than older mothers, and marijuana use may predict HIV risk behavior in offspring. Our goals were to (1) describe trajectories of marijuana use in teenage mothers and (2) determine if these trajectories were associated with early sexual behavior in their offspring. Pregnant adolescents (12–18 years) were recruited at a prenatal clinic and interviewed during pregnancy, at delivery, and during follow-up visits when offspring were 6, 10, 14 and 16 years old. At 16 years, 332 women (71 % Black, 29 % White) and their offspring were assessed. Mothers were asked about their marijuana use at each time point. Offspring reported on their sexual behavior at age 14. Trajectory analyses using growth mixture models revealed four maternal patterns of marijuana use: no use, only at the 6 year follow-up, quit by the 16 year follow-up, and used across most of the time points. The children of chronic users were more likely to have early sex. The maternal marijuana trajectory group variable remained a statistically significant predictor in multivariate models controlling for race, gender, socioeconomic status, child pubertal timing, child externalizing behavior problems, and child marijuana use. These findings suggest that a minority of teenage mothers continue to use marijuana over time. Chronic maternal marijuana use across a decade was associated with early sex in offspring (oral or vaginal sex by age 14). Early sexual behavior places these children at significantly higher risk of teenage pregnancy and HIV risk behaviors. PMID:24942139

Perceived Harm, Addictiveness, and Social Acceptability of Tobacco Products and Marijuana Among Young Adults: Marijuana, Hookah, and Electronic Cigarettes Win

PubMed Central

Berg, Carla J.; Stratton, Erin; Schauer, Gillian L.; Lewis, Michael; Wang, Yanwen; Windle, Michael; Kegler, Michelle

2015-01-01

Background There has been an increase in non-daily smoking, alternative tobacco product and marijuana use among young adults in recent years. Objectives This study examined perceptions of health risks, addictiveness, and social acceptability of cigarettes, cigar products, smokeless tobacco, hookah, electronic cigarettes, and marijuana among young adults and correlates of such perceptions. Methods In Spring 2013, 10,000 students at two universities in the Southeastern United States were recruited to complete an online survey (2,002 respondents), assessing personal, parental, and peer use of each product; and perceptions of health risks, addictiveness, and social acceptability of each of these products. Results Marijuana was the most commonly used product in the past month (19.2%), with hookah being the second most commonly used (16.4%). The least commonly used were smokeless tobacco products (2.6%) and electronic cigarettes (4.5%). There were high rates of concurrent product use, particularly among electronic cigarette users. The most positively perceived was marijuana, with hookah and electronic cigarettes being second. While tobacco use and related social factors, related positively, influenced perceptions of marijuana, marijuana use and related social factors were not associated with perceptions of any tobacco product. Conclusions/Importance Marketing efforts to promote electronic cigarettes and hookah to be safe and socially acceptable seem to be effective, while policy changes seem to be altering perceptions of marijuana and related social norms. Research is needed to document the health risks and addictive nature of emerging tobacco products and marijuana and evaluate efforts to communicate such risks to youth. PMID:25268294

Perceived harm, addictiveness, and social acceptability of tobacco products and marijuana among young adults: marijuana, hookah, and electronic cigarettes win.

PubMed

Berg, Carla J; Stratton, Erin; Schauer, Gillian L; Lewis, Michael; Wang, Yanwen; Windle, Michael; Kegler, Michelle

2015-01-01

There has been an increase in non-daily smoking, alternative tobacco product and marijuana use among young adults in recent years. This study examined perceptions of health risks, addictiveness, and social acceptability of cigarettes, cigar products, smokeless tobacco, hookah, electronic cigarettes, and marijuana among young adults and correlates of such perceptions. In Spring 2013, 10,000 students at two universities in the Southeastern United States were recruited to complete an online survey (2,002 respondents), assessing personal, parental, and peer use of each product; and perceptions of health risks, addictiveness, and social acceptability of each of these products. Marijuana was the most commonly used product in the past month (19.2%), with hookah being the second most commonly used (16.4%). The least commonly used were smokeless tobacco products (2.6%) and electronic cigarettes (4.5%). There were high rates of concurrent product use, particularly among electronic cigarette users. The most positively perceived was marijuana, with hookah and electronic cigarettes being second. While tobacco use and related social factors, related positively, influenced perceptions of marijuana, marijuana use and related social factors were not associated with perceptions of any tobacco product. Conclusions/Importance: Marketing efforts to promote electronic cigarettes and hookah to be safe and socially acceptable seem to be effective, while policy changes seem to be altering perceptions of marijuana and related social norms. Research is needed to document the health risks and addictive nature of emerging tobacco products and marijuana and evaluate efforts to communicate such risks to youth.

Polytobacco, marijuana, and alcohol use patterns in college students: A latent class analysis.

PubMed

Haardörfer, Regine; Berg, Carla J; Lewis, Michael; Payne, Jackelyn; Pillai, Drishti; McDonald, Bennett; Windle, Michael

2016-08-01

Limited research has examined polysubstance use profiles among young adults focusing on the various tobacco products currently available. We examined use patterns of various tobacco products, marijuana, and alcohol using data from the baseline survey of a multiwave longitudinal study of 3418 students aged 18-25 recruited from seven U.S. college campuses. We assessed sociodemographics, individual-level factors (depression; perceptions of harm and addictiveness,), and sociocontextual factors (parental/friend use). We conducted a latent class analysis and multivariable logistic regression to examine correlates of class membership (Abstainers were referent group). Results indicated five classes: Abstainers (26.1% per past 4-month use), Alcohol only users (38.9%), Heavy polytobacco users (7.3%), Light polytobacco users (17.3%), and little cigar and cigarillo (LCC)/hookah/marijuana co-users (10.4%). The most stable was LCC/hookah/marijuana co-users (77.3% classified as such in past 30-day and 4-month timeframes), followed by Heavy polytobacco users (53.2% classified consistently). Relative to Abstainers, Heavy polytobacco users were less likely to be Black and have no friends using alcohol and perceived harm of tobacco and marijuana use lower. Light polytobacco users were older, more likely to have parents using tobacco, and less likely to have friends using tobacco. LCC/hookah/marijuana co-users were older and more likely to have parents using tobacco. Alcohol only users perceived tobacco and marijuana use to be less socially acceptable, were more likely to have parents using alcohol and friends using marijuana, but less likely to have friends using tobacco. These findings may inform substance use prevention and recovery programs by better characterizing polysubstance use patterns. Copyright © 2016 Elsevier Ltd. All rights reserved.

Adolescent Marijuana Use and Perceived Ease of Access Before and After Recreational Marijuana Implementation in Colorado.

PubMed

Harpin, Scott B; Brooks-Russell, Ashley; Ma, Ming; James, Katherine A; Levinson, Arnold H

2018-02-23

As of January 1, 2017, eight states have approved laws for recreational marijuana use. While the social impacts of these changes remain under debate, the influence on adolescent marijuana use is a key policy and health issue across the U.S. To examine changes in adolescent marijuana-use behaviors in the first year after recreational marijuana implementation in Colorado, and to analyze the effect of retail marijuana store proximity on youth use and perceptions. Secondary analysis of Healthy Kids Colorado Survey data from 40 schools surveyed before and after recreational marijuana sales were implemented (2013 student n = 12,240; 2014 student n = 11,931). Self-reported marijuana use, ease of access, and perceived harms were compared between years and by proximity of recreational marijuana stores to surveyed schools. Adolescent marijuana use behaviors, wrongness of use, and perceptions of risk of harm were unchanged from baseline to one-year follow-up. Perceived ease of access to marijuana increased (from 46% to 52%). Proximity of recreational marijuana stores was not significantly associated with perceived ease of access to marijuana. Conclusions/Importance: In the first study of adolescent marijuana use and perceptions after state retail implementation of recreational marijuana, there was little change in adolescent marijuana use but a significant change in perception of ease of access. Public health workers and policymakers should continue to monitor these changes as essential for evaluating the impact of liberalization of marijuana policies.

Effect of marijuana use on cardiovascular and cerebrovascular mortality: A study using the National Health and Nutrition Examination Survey linked mortality file.

PubMed

Yankey, Barbara A; Rothenberg, Richard; Strasser, Sheryl; Ramsey-White, Kim; Okosun, Ike S

2017-11-01

Background Reports associate marijuana use with cardiovascular emergencies. Studies relating marijuana use to cardiovascular mortality are scarce. Recent advance towards marijuana use legalization emphasizes the importance of understanding relationships between marijuana use and cardiovascular deaths; the primary ranked mortality. Recreational marijuana is primarily smoked; we hypothesize that like cigarette smoking, marijuana use will be associated with increased cardiovascular mortalities. Design The design of this study was based on a mortality follow-up. Method We linked participants aged 20 years and above, who responded to questions on marijuana use during the 2005 US National Health and Nutrition Examination Survey to data from the 2011 public-use linked mortality file of the National Center for Health Statistics, Centers for Disease Control and Prevention. Only participants eligible for mortality follow-up were included. We conducted Cox proportional hazards regression analyses to estimate hazard ratios for hypertension, heart disease, and cerebrovascular mortality due to marijuana use. We controlled for cigarette smoking and other relevant variables. Results Of the 1213 eligible participants 72.5% were presumed to be alive. The total follow-up time was 19,569 person-years. Adjusted hazard ratios for death from hypertension among marijuana users compared to non-marijuana users was 3.42 (95% confidence interval: 1.20-9.79) and for each year of marijuana use was 1.04 (95% confidence interval: 1.00-1.07). Conclusion From our results, marijuana use may increase the risk for hypertension mortality. Increased duration of marijuana use is associated with increased risk of death from hypertension. Recreational marijuana use potentially has cardiovascular adverse effects which needs further investigation.

Psychological absorption. Affect investment in marijuana intoxication.

PubMed

Fabian, W D; Fishkin, S M

1991-01-01

Absorption (a trait capacity for total attentional involvement) was reported to increase during episodes of marijuana intoxication. Several subsets of the absorption scale items specifically characterized marijuana intoxication, and groups of users and nonusers showed differential affective involvement with these experiences. Additionally, within the drug-using group, a positive correlation between frequency of marijuana use and affective ratings of these experiences was found. The findings support the hypothesis that a specific type of alteration in consciousness that enhances capacity for total attentional involvement (absorption) characterizes marijuana intoxication, and that this enhancement may act as a reinforcer, possibly influencing future use.

Young Adults' Exposure to Alcohol- and Marijuana-Related Content on Twitter.

PubMed

Cabrera-Nguyen, E Peter; Cavazos-Rehg, Patricia; Krauss, Melissa; Bierut, Laura J; Moreno, Megan A

2016-03-01

Twitter is among the most popular social media platforms used by young adults, yet it has been underutilized in substance use research compared with older platforms (e.g., MySpace and Facebook). We took a first step toward studying the associations between exposure to pro-alcohol- and marijuana-related content among young adults via Twitter and current heavy episodic drinking and current marijuana use, respectively. We conducted an online survey of 587 (254 men, 333 women) Twitter users between ages 18 and 25 years in February 2014 using an online survey system that has been previously used in research on health behaviors and attitudes. Current heavy episodic drinking was significantly associated with higher levels of exposure to pro-alcohol content. Similarly, current marijuana use was significantly associated with higher levels of exposure to pro-marijuana content. Our findings suggest that in-depth research regarding young adults' exposure to pro-alcohol- and marijuana-related content via Twitter may provide a foundation for developing effective prevention messages on this social media platform to counter the pro-alcohol and marijuana messages.

Trends in U.S., Past-Year Marijuana Use from 1985–2009; An Age-Period-Cohort Analysis

PubMed Central

Miech, Richard; Koester, Stephen

2014-01-01

Background We present a formal age-period-cohort analysis to examine if the recent increase in past-year marijuana use among the young is specific to the younger generation or if, instead, it is part of a general increase present across cohorts of all ages. This is the first age-period-cohort analysis of past-year marijuana use that includes adult trends from 2001–09. Methods Data come from the National Survey on Drug Use and Health, a series of annual, nationally-representative, cross-sectional surveys of the U.S. civilian, non-institutionalized population. The analysis focuses on the 25 year time span from 1985–2009 and uses the recently developed ‘intrinsic estimator’ algorithm to estimate independent effects of age, period, and cohort. Results The recent increase in past-year marijuana use is not unique to the youngest birth cohorts. An independent, positive influence of cohort membership on past-year marijuana use, net of historical period and age effects, is smaller for today’s youngest cohorts than it was for the cohorts that came immediately before, and, in fact, is at its lowest level in three decades. The recent increase in marijuana use among the young is more consistent with a historical period effect that has acted across all cohorts. Period and cohort trends differ substantially for Hispanics. Conclusions The major forces that drive trends in past-year marijuana use are moving away from cohort-specific factors and toward broad-based influences that affect cohorts of all ages. Strategic public health and policy efforts aimed at countering the recent increase in past-year marijuana use should do the same. PMID:22361212

A virtue analysis of recreational marijuana use.

PubMed

Sullivan, Ezra; Austriaco, Nicanor

2016-05-01

Several empirical studies suggest that recreational marijuana is popularly perceived as an essentially harmless rite of passage that ends as young people settle into their careers and their adult intimate relationships. Is this perception accurate? To answer this question, we evaluate the morality of recreational marijuana use from a virtue perspective guided by the theological synthesis of St. Thomas Aquinas. Since the medical data reveals that recreational marijuana use is detrimental to the well-being of the user, we conclude that it is a vicious activity, an instance of the vice of intoxication, and as such would be morally illicit. In contrast to its medical use, the recreational use of marijuana cannot be justified for at least three reasons. First, as scientists have amply documented, it harms the organic functioning of the human body. Second, it impedes our ability to reason and in so doing does harm to us. Finally, it has lasting detrimental effects on the user and his neighbor, even when it occurs in a casual setting. Intoxication is always contrary to the integral good of the person. Thus, the use of marijuana is never warranted even for good, non-medical reasons.

Marijuana Use Associations with Pulmonary Symptoms and Function in Tobacco Smokers Enrolled in the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS).

PubMed

Morris, Madeline A; Jacobson, Sean R; Kinney, Gregory L; Tashkin, Donald P; Woodruff, Prescott G; Hoffman, Eric A; Kanner, Richard E; Cooper, Christopher B; Drummond, M Brad; Barr, R Graham; Oelsner, Elizabeth C; Make, Barry J; Han, MeiLan K; Hansel, Nadia N; O'Neal, Wanda K; Bowler, Russell P

2018-01-24

Background: Marijuana is often smoked via a filterless cigarette and contains similar chemical makeup as smoked tobacco. There are few publications describing usage patterns and respiratory risks in older adults or in those with chronic obstructive pulmonary disease (COPD). Methods: A cross-sectional analysis of current and former tobacco smokers from the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS) study assessed associations between marijuana use and pulmonary outcomes. Marijuana use was defined as never, former (use over 30 days ago), or current (use within 30 days). Respiratory health was assessed using quantitative high-resolution computed tomography (HRCT) scans, pulmonary function tests and questionnaire responses about respiratory symptoms. Results: Of the total 2304 participants, 1130 (49%) never, 982 (43%) former, and 192 (8%) current marijuana users were included. Neither current nor former marijuana use was associated with increased odds of wheeze (odds ratio [OR] 0.87, OR 0.97), cough (OR 1.22; OR 0.93) or chronic bronchitis (OR 0.87; OR 1.00) when compared to never users. Current and former marijuana users had lower quantitative emphysema ( P =0.004, P =0.03), higher percent predicted forced expiratory volume in 1 second (FEV 1 %) ( P <0.001, P <0.001), and percent predicted forced vital capacity (FVC%) ( p <0.001, P <0.001). Current marijuana users exhibited higher total tissue volume ( P =0.003) while former users had higher air trapping ( P <0.001) when compared to never marijuana users. Conclusions: Marijuana use was found to have little to no association with poor pulmonary health in older current and former tobacco smokers after adjusting for covariates. Higher forced expiratory volume in 1 second (FEV 1 ) and forced vital capacity (FVC) was observed among current marijuana users. However, higher joint years was associated with more chronic bronchitis symptoms (e.g., wheeze), and this study cannot determine if long

The Effects of Perceived Quality on Behavioral Economic Demand for Marijuana: A Web-Based Experiment

PubMed Central

Vincent, Paula C.; Collins, R. Lorraine; Liu, Liu; Yu, Jihnhee; De Leo, Joseph A.; Earleywine, Mitch

2016-01-01

Background Given the growing legalization of recreational marijuana use and related increase in its prevalence in the United States, it is important to understand marijuana's appeal. We used a behavioral economic (BE) approach to examine whether the reinforcing properties of marijuana, including “demand” for marijuana, varied as a function of its perceived quality. Methods Using an innovative, Web-based marijuana purchase task (MPT), a sample of 683 young-adult recreational marijuana users made hypothetical purchases of marijuana across three qualities (low, mid and high grade) at nine escalating prices per joint, ranging from $0/free to $20. Results We used nonlinear mixed effects modeling to conduct demand curve analyses, which produced separate demand indices (e.g., Pmax, elasticity) for each grade of marijuana. Consistent with previous research, as the price of marijuana increased, marijuana users reduced their purchasing. Demand also was sensitive to quality, with users willing to pay more for higher quality/grade marijuana. In regression analyses, demand indices accounted for significant variance in typical marijuana use. Conclusions This study illustrates the value of applying BE theory to young adult marijuana use. It extends past research by examining how perceived quality affects demand for marijuana and provides support for the validity of a Web-based MPT to examine the appeal of marijuana. Our results have implications for policies to regulate marijuana use, including taxation based on the quality of different marijuana products. PMID:27951424

The effects of perceived quality on behavioral economic demand for marijuana: A web-based experiment.

PubMed

Vincent, Paula C; Collins, R Lorraine; Liu, Liu; Yu, Jihnhee; De Leo, Joseph A; Earleywine, Mitch

2017-01-01

Given the growing legalization of recreational marijuana use and related increase in its prevalence in the United States, it is important to understand marijuana's appeal. We used a behavioral economic (BE) approach to examine whether the reinforcing properties of marijuana, including "demand" for marijuana, varied as a function of its perceived quality. Using an innovative, Web-based marijuana purchase task (MPT), a sample of 683 young-adult recreational marijuana users made hypothetical purchases of marijuana across three qualities (low, mid and high grade) at nine escalating prices per joint, ranging from $0/free to $20. We used nonlinear mixed effects modeling to conduct demand curve analyses, which produced separate demand indices (e.g., P max , elasticity) for each grade of marijuana. Consistent with previous research, as the price of marijuana increased, marijuana users reduced their purchasing. Demand also was sensitive to quality, with users willing to pay more for higher quality/grade marijuana. In regression analyses, demand indices accounted for significant variance in typical marijuana use. This study illustrates the value of applying BE theory to young adult marijuana use. It extends past research by examining how perceived quality affects demand for marijuana and provides support for the validity of a Web-based MPT to examine the appeal of marijuana. Our results have implications for policies to regulate marijuana use, including taxation based on the quality of different marijuana products. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Implications of marijuana legalization for adolescent substance use.

PubMed

Hopfer, Christian

2014-01-01

Marijuana that is legally available for adults has multiple implications for adolescent substance use. One potential effect that legalization may have is an increase in adolescent use to due increased availability, greater social acceptance, and possibly lower prices. Legalization may also facilitate the introduction of new formulations of marijuana (edible, vaporized) and with potentially higher potencies. It is unknown what adolescent consumption patterns will be if marijuana is widely available and marketed in different forms, or what effects different patterns of adolescent use will have on cognition, the development of marijuana use disorders, school performance, and the development of psychotic illnesses. Also unclear is whether adolescent users will be experiencing higher levels of tetrahydrocannabinol (THC) compared with previous generations of users due to higher potencies. Although previous studies of the effects of adolescent marijuana use provide some guidance for current policy and public health recommendations, many new studies will be needed that answer questions in the context of use within a legal adult environment. Claims that marijuana has medicinal benefits create additional challenges for adolescent prevention efforts, as they contrast with messages of its harmfulness. Prevention and treatment approaches will need to address perceptions of the safety of marijuana, claims of its medicinal use, and consider family-wide effects as older siblings and parents may increasingly openly consume and advocate for marijuana use. Guidance for primary care physicians will be needed regarded screening and counseling. Widespread legalization and acceptance of marijuana implies that as law enforcement approaches for marijuana control decline, public health, medical, and scientific efforts to understand and reduce negative consequences of adolescent marijuana use need to be substantially increased to levels commensurate with those efforts for tobacco and alcohol.

Association of marijuana use with oral HPV infection and periodontitis among Hispanic adults: Implications for oral cancer prevention.

PubMed

Ortiz, Ana P; González, Daisy; Ramos, Jeslie; Muñoz, Cristina; Reyes, Juan Carlos; Pérez, Cynthia M

2018-02-22

Despite limited data, research suggests that marijuana use is associated with oral HPV infection and periodontitis, two potential oropharyngeal cancer risk factors. We assessed these associations in a Hispanic adult population in Puerto Rico. A cross-sectional study of 735 adults assessed marijuana use, determined through an audio computer-assisted self-interview, and periodontitis and self-collection of oral HPV samples following the National Health and Nutrition Examination Survey methodology. The Centers of Disease Control and Prevention/American Academy of Periodontology definition was used for periodontitis. HPV typing was performed using polymerase chain reaction with modified L1 consensus primers (MY09/MY11). 26.5% of adults reported lifetime use of marijuana, 2.7% were frequent users (lifetime use ≥ 26 times, past year use ≥ 6 times, and past 30-day use ≥2 times), 5.7% had oral HPV infection, and 20.1% had severe periodontitis. The multivariate logistic regression analysis showed that frequent marijuana users were more likely to have severe periodontitis (OR = 2.91, 95%CI = 1.06 - 7.96) than never/once lifetime users after adjusting for age, sex, healthcare coverage, smoking, binge drinking, number of oral sex partners, and oral HPV infection. However, frequent marijuana use was not associated with oral HPV infection. Marijuana use was associated with periodontitis, but not with oral HPV infection. Further evaluation of the role of marijuana use in oral HPV infection and periodontitis may inform novel preventive public health strategies, as marijuana users could be at increased risk of oral cancer. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Association of race and age with treatment attendance and completion among adult marijuana users in community-based substance abuse treatment.

PubMed

Peters, Erica N; Hendricks, Peter S; Clark, C Brendan; Vocci, Frank J; Cropsey, Karen L

2014-01-01

African American youth who use marijuana are less likely to attend and complete treatment than white youth. Limited information is available on racial and age variation in treatment attendance and completion among adults who use marijuana. The current research examined differences in community-based substance abuse treatment attendance and completion between adult African American and white marijuana users in 2 independent samples from the US southeastern (N = 160; 70.6% African American) and mid-Atlantic (N = 450; 34.7% African American) regions. Attended at least 3 treatment sessions, successful treatment completion, number of days in treatment, and percentage of positive urine drug screens. Adjusted regression models examined the association of race, age, and the interaction of race and age with treatment attendance and completion. In the southeastern sample, successful treatment completion was significantly associated with the interaction of race and age (adjusted odds ratio = 1.35, 95% confidence interval = 1.08-1.69); whereas younger African Americans were less likely to complete treatment than older African Americans, age was unrelated to treatment completion among whites. In the mid-Atlantic sample, African Americans were significantly less likely to attend at least 3 treatment sessions (adjusted odds ratio = 0.37, 95% confidence interval = 0.23-0.58), and younger adult marijuana users were retained for fewer days in treatment (adjusted β = 0.13, 95% confidence interval = 0.27-2.48). Among African Americans, 37.9% (SD = 38.0) of urine drug screens tested positive for at least 1 illicit drug, and among whites, 34.2% (SD = 37.8%) tested positive; the percentage of positive urine drug screens was not associated with race or age. Among marijuana-using adults, treatment attendance and completion differ by race and age, and improvements in treatment completion may occur as some African Americans mature out of young adulthood.

Associations Between Microbiota, Mitochondrial Function, and Cognition in Chronic Marijuana Users.

PubMed

Panee, Jun; Gerschenson, Mariana; Chang, Linda

2018-03-01

Marijuana (MJ) use is associated with cognitive deficits. Both mitochondrial (mt) dysfunction and gut dysbiosis also affect cognition. We examined whether cognition is related to peripheral blood mononuclear cells' (PBMCs) mt function and fecal microbiota in chronic MJ users. Nineteen chronic MJ users and 20 non-users were evaluated using the Cognition Battery in NIH Toolbox, their mt function for ATP production, and basal and maximal respirations were measured in PBMCs using the Seahorse XFe96 Analyzer, and the abundances of Prevotella and Bacteroides (associated with plant-based and animal product-based diet, respectively) were calculated from stool microbiota analysis. Average Prevotella:Bacteroides ratio was ~13-fold higher in nonusers than users. Lifetime MJ use correlated inversely with Prevotella:Bacteroides ratio (p = 0.05), mt function (p = 0.0027-0.0057), and Flanker Inhibitory Control and Attention (p = 0.041). Prevotella abundance correlated positively, while Bacteroides abundance correlated inversely, with mt function across all participants (p = 0.0004-0.06). Prevotella abundance also correlated positively with scores of Fluid Cognition, Flanker Inhibitory Control and Attention, List Sorting, and Dimension Change Card Sort in MJ users, but not in non-users (interaction-p = 0.018-0.05). Similarly, mt function correlated positively with scores of Fluid Cognition and Flanker Inhibitory Control and Attention in MJ users, but not in non-users (interaction-p = 0.0018-0.08). These preliminary findings suggest that MJ use is associated with alterations of gut microbiota and mt function, which may further contribute to cognitive deficits. We posited that MJ-associated low vegetable/fruit intake may contribute to these changes. Future studies are needed to delineate the relationships among diet, microbiota, mt function, and cognition in MJ users.

It Depends on When You Ask: Motives for Using Marijuana Assessed Before versus After a Marijuana Use Event

PubMed Central

Shrier, Lydia A.; Scherer, Emily Blood

2014-01-01

Marijuana use motives are typically evaluated retrospectively using measures that summarize or generalize across episodes of use, which may compromise validity. Using Ecological Momentary Assessment data, we examined the main reason for a specific marijuana use event measured both prospectively and retrospectively. We then determined reason types, event characteristics, and user characteristics that predicted change in reason. Thirty-six medical outpatients age 15 to 24 years who used marijuana two times a week or more used a handheld computer to select their main reason for use from the five categories of the Marijuana Motives Measure (Simons, Correia, & Carey, 1998) just before and after each time they used marijuana over two weeks (n = 263 events with before/after reason). Reasons were examined individually and according to dimensions identified in motivational models of substance use (positive/negative, internal/external). Reason assessed before use changed to a different reason after use for 20% of events: 10% of events for pleasure; 21%, to cope; 35%, to be more social; 55%, to expand my mind; and 100%, to conform. In the multivariable model, external and expansion reasons each predicted change in reason for use (p < 0.0001 and p = 0.001, respectively). Youth were also more likely to change their reason if older (p = 0.04), if male (p = 0.02), and with weekend use (p = 0.002). Retrospective assessments of event-specific motives for marijuana use may be unreliable and therefore invalid for a substantial minority of events, particularly if use is for external or expansion reasons. PMID:25123342

The impact of the legalization of recreational marijuana on college students.

PubMed

Jones, Jacob; Nicole Jones, K; Peil, Jenny

2018-02-01

In January of 2014 the Regulate Marijuana like Alcohol Act or, Amendment 64, went into effect in Colorado. Even though it was the first state to enact recreational legalization, attitudes towards marijuana use have been changing for decades. Prompted by medical marijuana legalization, studies have found mixed results in regards to the impact that legalization has on frequency of use and abuse. With college students having the highest rates of use in the United States (U.S.), whether legal or not, it was important to explore the impact that legalization has on this population. In the current study, rates of marijuana and alcohol use in college students before and after recreational legalization were explored. Data was collected in four waves from October 2013 to March 2015, to be able to determine the trends in marijuana and alcohol use, and relationship between the substances. In addition, grade point average was measured as a possible consequence of marijuana use. We found the frequency of marijuana use in Colorado college students is much higher than the national average t(94445)=24.424, p<0.001, especially the percentage of daily or almost daily users, t(2191)=10.373, p<0.001. There were significant differences between the marijuana non-users and the once a week or more often but not daily marijuana users in grade point average, F(6, 227)=2.935, p<0.001. In addition, it seems that the relationship between alcohol and marijuana use in general is decreasing since the passing of Amendment 64, but not among the binge drinkers. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Effects of Marijuana on Human Cognition.

ERIC Educational Resources Information Center

Pearl, Joseph H.

Investigating the effects of marijuana on human psychological functioning, this study differs from previous research in two ways: 1) it is concerned with relatively complex cognitive processes; 2) it has a theoretical rationale. The general hypothesis of the study states that marijuana will impair its user's ability to form and use abstract…

Marijuana Craving During a Public Speaking Challenge: Understanding Marijuana Use Vulnerability among Women and those with Social Anxiety Disorder

PubMed Central

Silgado, José; Schmidt, Norman B.

2010-01-01

Social anxiety disorder (SAD) is associated with risk for developing marijuana dependence, yet it remains unclear whether urge to use marijuana increases in anticipation of social anxiety-provoking situation, during the situation, or afterwards (to avoid post-event processing). The present study examined the timing of marijuana craving in response to a social anxiety task among 60 (50% female; 33% with SAD) marijuana users randomly assigned to either a speech or reading task. Participants completed ratings of marijuana craving at baseline (prior to being informed of task assignment), before, during, and after task. Among women and participants with SAD, the speech task was associated with greater craving than the reading task. This effect was particularly pronounced during the social anxiety induction task. This effect was not observed for men or participants without SAD. Identification of timing of urge to use marijuana has important implications for treatment and relapse prevention of marijuana problems among women and people with SAD (a group at particular risk for marijuana-related problems). PMID:20797696

Survey of herbal cannabis (marijuana) use in rheumatology clinic attenders with a rheumatologist confirmed diagnosis.

PubMed

Ste-Marie, Peter A; Shir, Yoram; Rampakakis, Emmanouil; Sampalis, John S; Karellis, Angela; Cohen, Martin; Starr, Michael; Ware, Mark A; Fitzcharles, Mary-Ann

2016-12-01

Cannabinoids may hold potential for the management of rheumatic pain. Arthritis, often self-reported, is commonly cited as the reason for the use of medicinal herbal cannabis (marijuana). We have examined the prevalence of marijuana use among 1000 consecutive rheumatology patients with a rheumatologist-confirmed diagnosis and compared in an exploratory manner the clinical characteristics of medicinal users and nonusers. Current marijuana use, medicinal or recreational, was reported by 38 patients (3.8%; 95% CI: 2.8-5.2). Ever use of marijuana for medical purposes was reported by 4.3% (95% CI: 3.2-5.7), with 28 (2.8%; 95% CI: 1.9-4.0) reporting current medicinal use. Current medicinal users had a spectrum of rheumatic conditions, with over half diagnosed with osteoarthritis. Medicinal users were younger, more likely unemployed or disabled, and reported poorer global health. Pain report and opioid use was greater for users, but they had similar physician global assessment of disease status compared with nonusers. Medicinal users were more likely previous recreational users, with approximately 40% reporting concurrent recreational use. Therefore, less than 3% of rheumatology patients reported current use of medicinal marijuana. This low rate of use in patients with a rheumatologist-confirmed diagnosis is in stark contrast to the high rates of severe arthritis frequently reported by medicinal marijuana users, especially in Canada. Familiarity with marijuana as a recreational product may explain use for some as disease status was similar for both groups.

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. Copyright © 2014 Elsevier Ltd. All rights reserved.

Trajectories of Marijuana Use from Adolescence to Adulthood as Predictors of Unemployment Status in the Early Forties

PubMed Central

Zhang, Chenshu; Brook, Judith S.; Leukefeld, Carl G.; Brook, David W.

2016-01-01

Objectives To study the degree to which individuals in different trajectories of marijuana use are similar or different in terms of unemployment status at mean age 43. Methods We gathered longitudinal data on a prospective cohort taken from a community sample (N = 548). Forty nine percent of the original participants were females. Over 90% of the participants were white. The participants were followed from adolescence to early midlife. The mean ages of participants at the follow-up interviews were 14.1, 16.3, 22.3, 27.0, 31.9, 36.6, and 43.0, respectively. We used the growth mixture modeling (GMM) approach to identify the trajectories of marijuana use over a 29 year period. Results Five trajectories of marijuana use were identified: chronic users/decreasers (8.3%), quitters (18.6%), increasing users (7.3%), chronic occasional users (25.6%), and nonusers/experimenters (40.2%). Compared with nonusers/experimenters, chronic users/decreasers had a significantly higher likelihood of unemployment at mean age 43 (Adjusted Odds Ratio =3.51, 95% Confidence Interval = 1.13 – 10.91), even after controlling for the covariates. Conclusions and Scientific Significance The results of the associations between the distinct trajectories of marijuana use and unemployment in early midlife indicate that it is important to develop intervention programs targeting chronic marijuana use as well as unemployment in individuals at this stage of development. Results from this study should encourage clinicians, teachers, and parents to assess and treat chronic marijuana use in adolescents. PMID:26991779

Association of State Recreational Marijuana Laws With Adolescent Marijuana Use.

PubMed

Cerdá, Magdalena; Wall, Melanie; Feng, Tianshu; Keyes, Katherine M; Sarvet, Aaron; Schulenberg, John; O'Malley, Patrick M; Pacula, Rosalie Liccardo; Galea, Sandro; Hasin, Deborah S

2017-02-01

Historical shifts are occurring in marijuana policy. The effect of legalizing marijuana for recreational use on rates of adolescent marijuana use is a topic of considerable debate. To examine the association between the legalization of recreational marijuana use in Washington and Colorado in 2012 and the subsequent perceived harmfulness and use of marijuana by adolescents. We used data of 253 902 students in eighth, 10th, and 12th grades from 2010 to 2015 from Monitoring the Future, a national, annual, cross-sectional survey of students in secondary schools in the contiguous United States. Difference-in-difference estimates compared changes in perceived harmfulness of marijuana use and in past-month marijuana use in Washington and Colorado prior to recreational marijuana legalization (2010-2012) with postlegalization (2013-2015) vs the contemporaneous trends in other states that did not legalize recreational marijuana use in this period. Perceived harmfulness of marijuana use (great or moderate risk to health from smoking marijuana occasionally) and marijuana use (past 30 days). Of the 253 902 participants, 120 590 of 245 065(49.2%) were male, and the mean (SD) age was 15.6 (1.7) years. In Washington, perceived harmfulness declined 14.2% and 16.1% among eighth and 10th graders, respectively, while marijuana use increased 2.0% and 4.1% from 2010-2012 to 2013-2015. In contrast, among states that did not legalize recreational marijuana use, perceived harmfulness decreased by 4.9% and 7.2% among eighth and 10th graders, respectively, and marijuana use decreased by 1.3% and 0.9% over the same period. Difference-in-difference estimates comparing Washington vs states that did not legalize recreational drug use indicated that these differences were significant for perceived harmfulness (eighth graders: % [SD], -9.3 [3.5]; P = .01; 10th graders: % [SD], -9.0 [3.8]; P = .02) and marijuana use (eighth graders: % [SD], 5.0 [1.9]; P = .03; 10th graders

Can Marijuana Make It Better? Prospective Effects of Marijuana and Temperament on Risk for Anxiety and Depression

PubMed Central

Grunberg, Victoria A.; Cordova, Kismet A.; Bidwell, L. Cinnamon; Ito, Tiffany A.

2015-01-01

Increases in marijuana use in recent years highlight the importance of understanding how marijuana affects mental health. Of particular relevance is the effect of marijuana use on anxiety and depression given that marijuana use is highest among late adolescents/early adults, the same age range in which risk for anxiety and depression is the highest. Here we examine how marijuana use moderates the effects of temperament on level of anxiety and depression in a prospective design in which baseline marijuana use and temperament predict anxiety and depression one year later. We found that harm avoidance (HA) is associated with higher anxiety and depression a year later, but only among those low in marijuana use. Those higher in marijuana use show no relation between HA and symptoms of anxiety and depression. Marijuana use also moderated the effect of novelty seeking (NS), with symptoms of anxiety and depression increasing with NS only among those with high marijuana use. NS was unrelated to symptoms of anxiety and depression among those low in marijuana use. The temperament dimension of reward dependence was unrelated to anxiety and depression symptoms. Our results suggest that marijuana use does not have an invariant relationship with anxiety and depression, and that the effects of relatively stable temperament dimensions can be moderated by other contextual factors. PMID:26415059

Can marijuana make it better? Prospective effects of marijuana and temperament on risk for anxiety and depression.

PubMed

Grunberg, Victoria A; Cordova, Kismet A; Bidwell, L Cinnamon; Ito, Tiffany A

2015-09-01

Increases in marijuana use in recent years highlight the importance of understanding how marijuana affects mental health. Of particular relevance is the effect of marijuana use on anxiety and depression given that marijuana use is highest among late adolescents/early adults, the same age range in which risk for anxiety and depression is the highest. Here we examine how marijuana use moderates the effects of temperament on level of anxiety and depression in a prospective design in which baseline marijuana use and temperament predict anxiety and depression 1 year later. We found that harm avoidance (HA) is associated with higher anxiety and depression a year later, but only among those low in marijuana use. Those higher in marijuana use show no relation between HA and symptoms of anxiety and depression. Marijuana use also moderated the effect of novelty seeking (NS), with symptoms of anxiety and depression increasing with NS only among those with high marijuana use. NS was unrelated to symptoms of anxiety and depression among those low in marijuana use. The temperament dimension of reward dependence was unrelated to anxiety and depression symptoms. Our results suggest that marijuana use does not have an invariant relationship with anxiety and depression, and that the effects of relatively stable temperament dimensions can be moderated by other contextual factors. (c) 2015 APA, all rights reserved).

Correlates of Marijuana Drugged Driving and Openness to Driving While High: Evidence from Colorado and Washington.

PubMed

Davis, Kevin C; Allen, Jane; Duke, Jennifer; Nonnemaker, James; Bradfield, Brian; Farrelly, Matthew C; Shafer, Paul; Novak, Scott

2016-01-01

A potential unintended consequence of legalizing recreational marijuana is increased marijuana-related driving impairment. Some states where recreational marijuana is legal have begun implementing interventions to mitigate driving under the influence (DUI) of marijuana, including media campaigns to increase knowledge about DUI laws. However, little is known about the associations between knowledge of DUI laws and marijuana DUI behavior. In this study, we provide new data from a survey of marijuana users in Colorado and Washington to examine associations between marijuana drugged driving and two potential behavioral precursors of marijuana DUI. We also explore other factors that may influence marijuana DUI. Data are from an online survey of marijuana users in Colorado and Washington. Respondents who reported any marijuana use in the past 30 days (n = 865) served as the analytic sample. We examined prevalence of two behavioral outcomes: (1) any driving of a motor vehicle while high in the past year and (2) driving a motor vehicle within 1 hour of using marijuana 5 or more times in the past month. Additional outcomes measuring willingness to drive while high were also assessed. Logistic regressions were used to estimate each outcome as a function of two multi-item scales measuring knowledge of the legal consequences of driving high and perceptions that driving while high is not safe. Additional covariates for potential confounders were included in each model. Prevalence of past-year driving while under the influence of marijuana was 43.6% among respondents. The prevalence of driving within 1 hour of using marijuana at least 5 times in the past month was 23.9%. Increased perception that driving high is unsafe was associated with lower odds of past-year marijuana DUI (OR = 0.31, P < 0.01) and lower past-month odds of driving 5 or more times within 1 hour of using marijuana (OR = 0.26, P < 0.01). Increased knowledge of marijuana DUI laws was also associated with lower

Toking, Vaping, and Eating for Health or Fun: Marijuana Use Patterns in Adults, U.S., 2014.

PubMed

Schauer, Gillian L; King, Brian A; Bunnell, Rebecca E; Promoff, Gabbi; McAfee, Timothy A

2016-01-01

Policies legalizing marijuana for medical and recreational use have been increasing in the U.S. Considering the potential impact of these policies, important knowledge gaps exist, including information about the prevalence of various modes of marijuana use (e.g., smoked in joints, bowls, bongs; consumed in edibles or drinks) and about medical versus recreational use. Accordingly, this study assessed (1) prevalence and correlates of modes of current and ever marijuana use and (2) prevalence of medicinal and recreational marijuana use in U.S. adults. Data came from Summer Styles (n=4,269), a nationally representative consumer panel survey of adults aged ≥18 years, collected in 2014. The survey asked about past 30-day (current) and ever mode of marijuana use and current reason for use (medicinal, recreational, both). Weighted prevalence estimates were computed and correlates were assessed in 2014 using logistic regression. Overall, 7.2% of respondents reported current marijuana use; 34.5% reported ever use. Among current users, 10.5% reported medicinal-only use, 53.4% reported recreational-only use, and 36.1% reported both. Use of bowl or pipe (49.5%) and joint (49.2%) predominated among current marijuana users, with lesser use of bong, water pipe, or hookah (21.7%); blunts (20.3%); edibles/drinks (16.1%); and vaporizers (7.6%); 92.1% of the sample reported combusted-only marijuana use. Combusted modes of marijuana use are most prevalent among U.S. adults, with a majority using marijuana for recreation. In light of changing policies and patterns of use, improved marijuana surveillance is critical for public health planning. Copyright © 2016 American Journal of Preventive Medicine. All rights reserved.

Temporal trends in marijuana attitudes, availability and use in Colorado compared to non-medical marijuana states: 2003-11.

PubMed

Schuermeyer, Joseph; Salomonsen-Sautel, Stacy; Price, Rumi Kato; Balan, Sundari; Thurstone, Christian; Min, Sung-Joon; Sakai, Joseph T

2014-07-01

In 2009, policy changes were accompanied by a rapid increase in the number of medical marijuana cardholders in Colorado. Little published epidemiological work has tracked changes in the state around this time. Using the National Survey on Drug Use and Health, we tested for temporal changes in marijuana attitudes and marijuana-use-related outcomes in Colorado (2003-11) and differences within-year between Colorado and thirty-four non-medical-marijuana states (NMMS). Using regression analyses, we further tested whether patterns seen in Colorado prior to (2006-8) and during (2009-11) marijuana commercialization differed from patterns in NMMS while controlling for demographics. Within Colorado those reporting "great-risk" to using marijuana 1-2 times/week dropped significantly in all age groups studied between 2007-8 and 2010-11 (e.g. from 45% to 31% among those 26 years and older; p=0.0006). By 2010-11 past-year marijuana abuse/dependence had become more prevalent in Colorado for 12-17 year olds (5% in Colorado, 3% in NMMS; p=0.03) and 18-25 year olds (9% vs. 5%; p=0.02). Regressions demonstrated significantly greater reductions in perceived risk (12-17 year olds, p=0.005; those 26 years and older, p=0.01), and trend for difference in changes in availability among those 26 years and older and marijuana abuse/dependence among 12-17 year olds in Colorado compared to NMMS in more recent years (2009-11 vs. 2006-8). Our results show that commercialization of marijuana in Colorado has been associated with lower risk perception. Evidence is suggestive for marijuana abuse/dependence. Analyses including subsequent years 2012+ once available, will help determine whether such changes represent momentary vs. sustained effects. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Marijuana’s Acute Effects on Cognitive Bias for Affective and Marijuana Cues

PubMed Central

Metrik, Jane; Aston, Elizabeth R.; Kahler, Christopher W.; Rohsenow, Damaris J.; McGeary, John E.; Knopik, Valerie S.

2015-01-01

Marijuana produces acute increases in positive subjective effects and decreased reactivity to negative affective stimuli, though may also acutely induce anxiety. Implicit attentional and evaluative processes may explicate marijuana’s ability to acutely increase positive and negative emotions. This within-subjects study examined whether smoked marijuana with 2.7–3.0 % delta-9-tetrahydrocannabinol (THC), relative to placebo, acutely changed attentional processing of rewarding and negative affective stimuli as well as marijuana-specific stimuli. On two separate days, regular marijuana users (N=89) smoked placebo or active THC cigarette and completed subjective ratings of mood, intoxication, urge to smoke marijuana, and two experimental tasks: Pleasantness Rating (response latency and perceived pleasantness of affective and marijuana-related stimuli) and Emotional Stroop (attentional bias to affective stimuli). On the Pleasantness Rating task, active marijuana increased response latency to negatively-valenced and marijuana-related (vs. neutral) visual stimuli, beyond a general slowing of response. Active marijuana also increased pleasantness ratings of marijuana images, although to a lesser extent than placebo due to reduced marijuana urge after smoking. Overall, active marijuana did not acutely change processing of positive emotional stimuli. There was no evidence of attentional bias to affective word stimuli on the Emotional Stroop task with the exception of attentional bias to positive word stimuli in the subgroup of marijuana users with cannabis dependence. Marijuana may increase allocation of attentional resources towards marijuana-specific and negatively-valenced visual stimuli without altering processing of positively-valenced stimuli. Marijuana-specific cues may be more attractive with higher levels of marijuana craving and less wanted with low craving levels. PMID:26167716

Medicinal and recreational marijuana use among HIV-infected women in the Women's Interagency HIV Study (WIHS) cohort, 1994-2010.

PubMed

Dʼsouza, Gypsyamber; Matson, Pamela A; Grady, Cynthia D; Nahvi, Shadi; Merenstein, Dan; Weber, Kathleen M; Greenblatt, Ruth; Burian, Pam; Wilson, Tracey E

2012-12-15

Despite the major benefits of effective antiretroviral therapy on HIV-related survival, there is an ongoing need to help alleviate medication side effects related to antiretroviral therapy use. Initial studies suggest that marijuana use may reduce HIV-related symptoms, but medical marijuana use among HIV-infected individuals has not been well described. The authors evaluated trends in marijuana use and reported motivations for use among 2776 HIV-infected women in the Women's Interagency HIV Study between October 1994 and March 2010. Predictors of any and daily marijuana use were explored in multivariate logistic regression models clustered by person using generalized estimating equation. In 2009, participants were asked if their marijuana use was medical, "meaning prescribed by a doctor," or recreational, or both. Over the 16 years of this study, the prevalence of current marijuana use decreased significantly from 21% to 14%. In contrast, daily marijuana use almost doubled from 3.3% to 6.1% of all women and from 18% to 51% of current marijuana users. Relaxation, appetite improvement, reduction of HIV-related symptoms, and social use were reported as common reasons for marijuana use. In 2009, most marijuana users reported either purely medicinal use (26%) or both medicinal and recreational usage (29%). Daily marijuana use was associated with higher CD4 cell count, quality of life, and older age. Demographic characteristics and risk behaviors were associated with current marijuana use overall but were not predictors of daily use. This study suggests that both recreational and medicinal marijuana use are relatively common among HIV-infected women in the United States.

Marijuana Usage and Hypnotic Susceptibility

ERIC Educational Resources Information Center

Franzini, Louis R.; McDonald, Roy D.

1973-01-01

Anonymous self-reported drug usage data and hypnotic susceptibility scores were obtained from 282 college students. Frequent marijuana users (more than 10 times) showed greater susceptibility to hypnosis than nonusers. (Author)

The Associations Between E-Cigarettes and Binge Drinking, Marijuana Use, and Energy Drinks Mixed With Alcohol.

PubMed

Milicic, Sandra; Leatherdale, Scott T

2017-03-01

Use of e-cigarettes by youth is proliferating worldwide, but little is known about the behavioral profile of youth e-cigarette users and the association of e-cigarette use with other health-risky behaviors. This study examines the associations between e-cigarette use and tobacco, marijuana, and alcohol use among a large sample of Canadian youth. Using Canadian data from 39,837 grade 9 to 12 students who participated in year 3 (2014-2015) of the COMPASS study, logistic regression models were used to examine how current use of e-cigarettes were associated with tobacco, marijuana, binge drinking, and energy drinks mixed with alcohol. Pearson's chi-square tests were used to examine subgroup differences by sex. Overall, 9.75% of respondents were current e-cigarette users. Current cigarette smokers (odds ratio [OR] = 3.009), current marijuana users (OR = 5.549), and noncurrent marijuana users (OR = 3.653) were more likely to report using e-cigarettes than noncigarette smokers and nonmarijuana users. Gender differences among males and females showed higher risk of e-cigarette use among female current marijuana users (OR = 7.029) relative to males (OR = 4.931) and female current smokers (OR = 3.284) compared to males (OR = 2.862). Compared to nonbinge drinkers, weekly (OR = 3.253), monthly (OR = 3.113), and occasional (OR = 2.333) binge drinkers were more likely to use e-cigarettes. Similarly, students who consume energy drinks mixed with alcohol (OR = 1.650) were more likely to use e-cigarettes compared to students who do not consume them. We identify that youth who binge drink or use marijuana have a greater increased risk for using e-cigarettes compared to cigarette smokers. These data suggest that efforts to prevent e-cigarette use should not only be discussed in the domain of tobacco control. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Association of State Recreational Marijuana Laws With Adolescent Marijuana Use

PubMed Central

Cerdá, Magdalena; Wall, Melanie; Feng, Tianshu; Keyes, Katherine M.; Sarvet, Aaron; Schulenberg, John; O’Malley, Patrick M.; Pacula, Rosalie Liccardo; Galea, Sandro; Hasin, Deborah S.

2017-01-01

IMPORTANCE Historical shifts are occurring in marijuana policy. The effect of legalizing marijuana for recreational use on rates of adolescent marijuana use is a topic of considerable debate. OBJECTIVE To examine the association between the legalization of recreational marijuana use in Washington and Colorado in 2012 and the subsequent perceived harmfulness and use of marijuana by adolescents. DESIGN, SETTING, AND PARTICIPANTS We used data of 253 902 students in eighth, 10th, and 12th grades from 2010 to 2015 from Monitoring the Future, a national, annual, cross-sectional survey of students in secondary schools in the contiguous United States. Difference-indifference estimates compared changes in perceived harmfulness of marijuana use and in past-month marijuana use in Washington and Colorado prior to recreational marijuana legalization (2010–2012) with post legalization (2013–2015) vs the contemporaneous trends in other states that did not legalize recreational marijuana use in this period. MAIN OUTCOMES AND MEASURES Perceived harmfulness of marijuana use (great or moderate risk to health from smoking marijuana occasionally) and marijuana use (past 30 days). RESULTS Of the 253 902 participants, 120 590 of 245 065(49.2%) were male, and the mean (SD) age was 15.6 (1.7) years. In Washington, perceived harmfulness declined 14.2%and 16.1% among eighth and 10th graders, respectively, while marijuana use increased 2.0% and 4.1% from 2010–2012 to 2013–2015. In contrast, among states that did not legalize recreational marijuana use, perceived harmfulness decreased by 4.9% and 7.2%among eighth and 10th graders, respectively, and marijuana use decreased by 1.3%and 0.9%over the same period. Difference-in-difference estimates comparing Washington vs states that did not legalize recreational drug use indicated that these differences were significant for perceived harmfulness (eighth graders:%[SD], −9.3 [3.5]; P = .01; 10th graders:%[SD], −9.0 [3.8]; P = .02) and

Behavioral Aspects of Marijuana Use.

ERIC Educational Resources Information Center

Paulson, Patricia

This paper examines the behavioral aspects of marijuana use. The focus of the study was to investigate the attitudes and practices toward drugs by users and non-users and the relationship of these attitudes and practices to selected psychosocial factors. A survey instrument in the form of an anonymous questionnaire was developed and administered…

What Did You Expect?: The Interaction Between Cigarette and Blunt vs. Non-Blunt Marijuana Use among African American Young Adults

PubMed Central

Ramo, Danielle

2017-01-01

Background Marijuana and tobacco co-use is highly prevalent among African American young adults. In an effort to inform prevention and treatment interventions, the current study examined the expectancies around the co-use of marijuana and cigarettes among African American young adults. Methods An anonymous online survey recruited African American adults (N = 111) age 18 to 29 who reported past-month marijuana and cigarette co-use. Participants completed the 14-item Nicotine and Marijuana Interaction Expectancy (NAMIE) Questionnaire, with three scales: (1) marijuana use increases tobacco use and urges, (2) tobacco use increases marijuana use and urges and (3) smoking to cope with marijuana urges. Participants also answered questions about marijuana and tobacco initiation and use. Analyses were conducted separately for blunt co-users (i.e., blunt and cigarette use) and non-blunt co-users (i.e., non-blunt marijuana and cigarette use). Results A majority of co-users (66%) used blunts as a form of co-use. Non-blunt co-users had higher expectancy scores on NAMIE scales 2 and 3 than blunt co-users. However, only blunt co-users showed a positive association between severity of marijuana use and NAMIE scales 2 (p <.01) and 3 (p <.01). Conclusions Findings provide further evidence for the use of the NAMIE and suggest a need to assess and address expectations regarding marijuana and tobacco co-use in prevention and treatment interventions, especially among young African American adults who co-use blunts and cigarettes. PMID:29333104

Epidemiologic review of marijuana use and cancer risk.

PubMed

Hashibe, Mia; Straif, Kurt; Tashkin, Donald P; Morgenstern, Hal; Greenland, Sander; Zhang, Zuo-Feng

2005-04-01

Marijuana is the most commonly used illegal drug in the United States and is considered by young adults to be the illicit drug with the least risk. On the other hand, marijuana smoke contains several of the same carcinogens and co-carcinogens as the tar from tobacco, raising concerns that smoking of marijuana may be a risk factor for tobacco-related cancers. We reviewed two cohort studies and 14 case-control studies with assessment of the association of marijuana use and cancer risk. In the cohort studies, increased risks of lung or colorectal cancer due to marijuana smoking were not observed, but increased risks of prostate and cervical cancers among non-tobacco smokers, as well as adult-onset glioma among tobacco and non-tobacco smokers, were observed. The 14 case-control studies included four studies on head and neck cancers, two studies on lung cancer, two studies on non-Hodgkin's lymphoma, one study on anal cancer, one study on penile cancer, and four studies on childhood cancers with assessment of parental exposures. Zhang and colleagues reported that marijuana use may increase risk of head and neck cancers in a hospital-based case-control study in the United States, with dose-response relations for both frequency and duration of use. However, Rosenblatt and co-workers reported no association between oral cancer and marijuana use in a population-based case-control study. An eightfold increase in risk among marijuana users was observed in a lung cancer study in Tunisia. However, there was no assessment of the dose response, and marijuana may have been mixed with tobacco. Parental marijuana use during gestation was associated with increased risks of childhood leukemia, astrocytoma, and rhabdomyosarcoma, but dose-response relations were not assessed. In summary, sufficient studies are not available to adequately evaluate marijuana impact on cancer risk. Several limitations of previous studies include possible underreporting where marijuana use is illegal, small

The high prevalence of substance use disorders among recent MDMA users compared with other drug users: implications for intervention

PubMed Central

Wu, Li-Tzy; Parrott, Andy C.; Ringwalt, Christopher L.; Patkar, Ashwin A.; Mannelli, Paolo; Blazer, Dan G.

2009-01-01

Aim In light of the resurgence in MDMA use and its association with polysubstance use, we investigated the 12-month prevalence of substance use disorders (SUDs) among adult MDMA users to determine whether they are at risk of other drug-related problems that would call for targeted interventions. Methods Data were drawn from the 2006 National Survey on Drug Use and Health. Past-year adult drug users were grouped into three mutually exclusive categories: 1) recent MDMA users, who had used the drug within the past year; 2) former MDMA users, who had a history of using this drug but had not done so within the past year; and 3) other drug users, who had never used MDMA. Logistic regression procedures were used to estimate the association between respondents’ SUDs and MDMA use while adjusting for their socioeconomic status, mental health, age of first use, and history of polydrug use. Results Approximately 14% of adults reported drug use in the past year, and 24% of those past-year drug users reported a history of MDMA use. Recent MDMA users exhibited the highest prevalence of disorders related to alcohol (41%), marijuana (30%), cocaine (10%), pain reliever/opioid (8%), and tranquilizer (3%) use. Adjusted logistic regression analyses revealed that, relative to other drug users, those who had recently used MDMA were twice as likely to meet criteria for marijuana and pain reliever/opioid use disorders. They were also about twice as likely as former MDMA users to meet criteria for marijuana, cocaine, and tranquilizer use disorders. Conclusions Seven out of ten recent MDMA users report experiencing an SUD in the past year. Adults who have recently used MDMA should be screened for possible SUDs to ensure early detection and treatment. PMID:19361931

Uni-Morbid and Co-Occurring Marijuana and Tobacco Use: Examination of Concurrent Associations with Negative Mood States

PubMed Central

Bonn-Miller, Marcel O.; Zvolensky, Michael J.; Johnson, Kirsten A.

2010-01-01

The aim of the current investigation was to examine uni-morbid and co-occurring tobacco and marijuana use in relation to the negative emotional symptoms of anxiety and depression. Participants were 250 adult individuals (132 female; mage = 22.43, SD = 9.00), falling into one of four non-overlapping substance use categories: tobacco use only (n = 39), marijuana use only (n = 62), co-occurring tobacco and marijuana use (n = 82), and neither tobacco nor marijuana use (n = 67). Results revealed three key findings. First, tobacco-only using individuals reported significantly greater negative affectivity than any of the other groups. Second, tobacco-only users reported greater anxious arousal symptoms than either the marijuana or non-substance-using groups, but not the combined group. Third, tobacco-only users reported greater levels of depressive symptoms than either marijuana users or non-substance-users. These findings provide novel information about tobacco and marijuana use, and how these variables relate to the experience of general and specific types of negative emotional symptoms. PMID:20390700

Marijuana

MedlinePlus

... Search Share Print Home » Drugs of Abuse » Marijuana Marijuana Email Facebook Twitter Brief Description Marijuana refers to ... drugs-abuse/marijuana. . press ctrl+c to copy Marijuana and Cannabinoids: A Neuroscience Research Summit March 22- ...

State-Level Medical Marijuana Laws, Marijuana Use and Perceived Availability of Marijuana Among the General U.S. Population

PubMed Central

Martins, Silvia S.; Mauro, Christine M.; Santaella-Tenorio, Julian; Kim, June H.; Cerda, Magdalena; Keyes, Katherine M.; Hasin, Deborah S.; Galea, Sandro; Wall, Melanie

2016-01-01

Background Little is known on how perceived availability of marijuana is associated with medical marijuana laws. We examined the relationship between medical marijuana laws (MML) and the prevalence of past-month marijuana use, with perceived availability of marijuana. Methods Data were from respondents included in the National Survey of Drug Use and Health restricted use data portal 2004–2013. Multilevel logistic regression of individual- level data was used to test differences between MML and non-MML states and changes in prevalence of past-month marijuana use and perceived availability from before to after passage of MML among adolescents, young adults and older adults controlling for demographics. Results Among adults 26+, past-month prevalence of marijuana use increased from 5.87% to 7.15% after MML passage (Adjusted Odds Ratio (AOR): 1.24 [1.16–1.31]), but no change in prevalence of use was found for 12–17 or 18–25 year-olds. Perceived availability of marijuana increased after MML were enacted among those 26+ but not in younger groups. Among all age groups, prevalence of marijuana use and perception of it being easily available was higher in states that would eventually pass MML by 2013 compared to those that had not. Perceived availability was significantly associated with increased risk of past-month marijuana use in all age groups. Conclusion Evidence suggests perceived availability as a driver of change in use of marijuana due to MML. To date, this has only occurred in adults 26+ and different scenarios that could explain this change need to be further explored. PMID:27755989

State-level medical marijuana laws, marijuana use and perceived availability of marijuana among the general U.S. population.

PubMed

Martins, Silvia S; Mauro, Christine M; Santaella-Tenorio, Julian; Kim, June H; Cerda, Magdalena; Keyes, Katherine M; Hasin, Deborah S; Galea, Sandro; Wall, Melanie

2016-12-01

Little is known on how perceived availability of marijuana is associated with medical marijuana laws. We examined the relationship between medical marijuana laws (MML) and the prevalence of past-month marijuana use, with perceived availability of marijuana. Data were from respondents included in the National Survey of Drug Use and Health restricted use data portal 2004-2013. Multilevel logistic regression of individual-level data was used to test differences between MML and non-MML states and changes in prevalence of past-month marijuana use and perceived availability from before to after passage of MML among adolescents, young adults and older adults controlling for demographics. Among adults 26+, past-month prevalence of marijuana use increased from 5.87% to 7.15% after MML passage (Adjusted Odds Ratio (AOR): 1.24 [1.16-1.31]), but no change in prevalence of use was found for 12-17 or 18-25 year-olds. Perceived availability of marijuana increased after MML was enacted among those 26+ but not in younger groups. Among all age groups, prevalence of marijuana use and perception of it being easily available was higher in states that would eventually pass MML by 2013 compared to those that had not. Perceived availability was significantly associated with increased risk of past-month marijuana use in all age groups. Evidence suggests perceived availability as a driver of change in use of marijuana due to MML. To date, this has only occurred in adults 26+ and different scenarios that could explain this change need to be further explored. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Medical marijuana policies and hospitalizations related to marijuana and opioid pain reliever.

PubMed

Shi, Yuyan

2017-04-01

Twenty-eight states in the U.S have legalized medical marijuana, yet its impacts on severe health consequences such as hospitalizations remain unknown. Meanwhile, the prevalence of opioid pain reliever (OPR) use and outcomes has increased dramatically. Recent studies suggested unintended impacts of legalizing medical marijuana on OPR, but the evidence is still limited. This study examined the associations between state medical marijuana policies and hospitalizations related to marijuana and OPR. State-level annual administrative records of hospital discharges during 1997-2014 were obtained from the State Inpatient Databases (SID). The outcome variables were rates of hospitalizations involving marijuana dependence or abuse, opioid dependence or abuse, and OPR overdose in 1000 discharges. Linear time-series regressions were used to assess the associations of implementing medical marijuana policies to hospitalizations, controlling for other marijuana- and OPR-related policies, socioeconomic factors, and state and year fixed effects. Hospitalizations related to marijuana and OPR increased sharply by 300% on average in all states. Medical marijuana legalization was associated with 23% (p=0.008) and 13% (p=0.025) reductions in hospitalizations related to opioid dependence or abuse and OPR overdose, respectively; lagged effects were observed after policy implementation. The operation of medical marijuana dispensaries had no independent impacts on OPR-related hospitalizations. Medical marijuana polices had no associations with marijuana-related hospitalizations. Medical marijuana policies were significantly associated with reduced OPR-related hospitalizations but had no associations with marijuana-related hospitalizations. Given the epidemic of problematic use of OPR, future investigation is needed to explore the causal pathways of these findings. Copyright © 2017 Elsevier B.V. All rights reserved.

Medical marijuana policies and hospitalizations related to marijuana and opioid pain reliever*

PubMed Central

Shi, Yuyan

2017-01-01

Objectives Twenty-eight states in the U.S. have legalized medical marijuana, yet its impacts on severe health consequences such as hospitalizations remain unknown. Meanwhile, the prevalence of opioid pain reliever (OPR) use and outcomes has increased dramatically. Recent studies suggested unintended impacts of legalizing medical marijuana on OPR, but the evidence is still limited. This study examined the associations between state medical marijuana policies and hospitalizations related to marijuana and OPR. Methods State-level annual administrative records of hospital discharges during 1997–2014 were obtained from the State Inpatient Databases (SID). The outcome variables were rates of hospitalizations involving marijuana dependence or abuse, opioid dependence or abuse, and OPR overdose in 1,000 discharges. Linear time-series regressions were used to assess the associations of implementing medical marijuana policies to hospitalizations, controlling for other marijuana- and OPR-related policies, socioeconomic factors, and state and year fixed effects. Results Hospitalizations related to marijuana and OPR increased sharply by 300% on average in all states. Medical marijuana legalization was associated with 23% (p=.008) and 13% (p=.025) reductions in hospitalizations related to opioid dependence or abuse and OPR overdose, respectively; lagged effects were observed after policy implementation. The operation of medical marijuana dispensaries had no independent impacts on OPR- related hospitalizations. Medical marijuana polices had no associations with marijuana-related hospitalizations. Conclusion Medical marijuana policies were significantly associated with reduced OPR-related hospitalizations but had no associations with marijuana-related hospitalizations. Given the epidemic of problematic use of OPR, future investigation is needed to explore the causal pathways of these findings. PMID:28259087

Marijuana Use, Recent Marijuana Initiation, and Progression to Marijuana Use Disorder Among Young Male and Female Adolescents Aged 12–14 Living in US Households

PubMed Central

Forman-Hoffman, Valerie L; Glasheen, Cristie; Batts, Kathryn R

2017-01-01

Marijuana initiation during adolescence, and early adolescence in particular, is associated with adverse health consequences. Our study used 2005–2014 data from the annual, cross-sectional National Survey on Drug Use and Health to study the prevalence and correlates of marijuana initiation, use, and marijuana use disorder (MUD; abuse or dependence) among 12- to 14-year olds living in civilian US households (n = 84 954). Examined correlates included age, sex, race/ethnicity, poverty status, metropolitan status, year of survey, depression, tobacco use, alcohol use, and fighting at school. Sex differences in the correlates of lifetime use and past year marijuana initiation were tested via interaction. Lifetime prevalence of marijuana use was 5.5%; 3.2% reported past year initiation. About 1 in 6 (16.8%) past year initiates progressed to MUD within 12 months of first use. Although men had higher prevalence of lifetime use than women, past year initiation did not differ by sex. On examining the sex*race/ethnicity interaction effects, findings determined that non-Hispanic black and Hispanic men had higher prevalence estimates of ever using marijuana and incidence of past year initiation as compared with non-Hispanic white men; these race/ethnicity differences were not found among women. Identifying correlates of initiation and progression to MUD among young adolescents is critical to improve prevention and treatment program targets. PMID:28615948

Effects of smoking marijuana on focal attention and brain blood flow.

PubMed

O'Leary, Daniel S; Block, Robert I; Koeppel, Julie A; Schultz, Susan K; Magnotta, Vincent A; Ponto, Laura Boles; Watkins, G Leonard; Hichwa, Richard D

2007-04-01

Using an attention task to control cognitive state, we previously found that smoking marijuana changes regional cerebral blood flow (rCBF). The present study measured rCBF during tasks requiring attention to left and right ears in different conditions. Twelve occasional marijuana users (mean age 23.5 years) were imaged with PET using [15O]water after smoking marijuana or placebo cigarettes as they performed a reaction time (RT) baseline task, and a dichotic listening task with attend-right- and attend-left-ear instructions. Smoking marijuana, but not placebo, resulted in increased normalized rCBF in orbital frontal cortex, anterior cingulate, temporal pole, insula, and cerebellum. RCBF was reduced in visual and auditory cortices. These changes occurred in all three tasks and replicated our earlier studies. They appear to reflect the direct effects of marijuana on the brain. Smoking marijuana lowered rCBF in auditory cortices compared to placebo but did not alter the normal pattern of attention-related rCBF asymmetry (i.e., greater rCBF in the temporal lobe contralateral to the direction of attention) that was also observed after placebo. These data indicate that marijuana has dramatic direct effects on rCBF, but causes relatively little change in the normal pattern of task-related rCBF on this auditory focused attention task. Copyright 2007 John Wiley & Sons, Ltd.

Marijuana use and increased risk of squamous cell carcinoma of the head and neck.

PubMed

Zhang, Z F; Morgenstern, H; Spitz, M R; Tashkin, D P; Yu, G P; Marshall, J R; Hsu, T C; Schantz, S P

1999-12-01

Marijuana is the most commonly used illegal drug in the United States. In some subcultures, it is widely perceived to be harmless. Although the carcinogenic properties of marijuana smoke are similar to those of tobacco, no epidemiological studies of the relationship between marijuana use and head and neck cancer have been published. The relationship between marijuana use and head and neck cancer was investigated by a case-control study of 173 previously untreated cases with pathologically confirmed diagnoses of squamous cell carcinoma of the head and neck and 176 cancer-free controls at Memorial Sloan-Kettering Cancer Center between 1992 and 1994. Epidemiological data were collected by using a structured questionnaire, which included history of tobacco smoking, alcohol use, and marijuana use. The associations between marijuana use and head and neck cancer were analyzed by Mantel-Haenszel methods and logistic regression models. Controlling for age, sex, race, education, alcohol consumption, pack-years of cigarette smoking, and passive smoking, the risk of squamous cell carcinoma of the head and neck was increased with marijuana use [odds ratio (OR) comparing ever with never users, 2.6; 95% confidence interval (CI), 1.1-6.6]. Dose-response relationships were observed for frequency of marijuana use/day (P for trend <0.05) and years of marijuana use (P for trend <0.05). These associations were stronger for subjects who were 55 years of age and younger (OR, 3.1; 95% CI, 1.0-9.7). Possible interaction effects of marijuana use were observed with cigarette smoking, mutagen sensitivity, and to a lesser extent, alcohol use. Our results suggest that marijuana use may increase the risk of head and neck cancer with a strong dose-response pattern. Our analysis indicated that marijuana use may interact with mutagen sensitivity and other risk factors to increase the risk of head and neck cancer. The results need to be interpreted with some caution in drawing causal inferences

Cue-elicited increases in incentive salience for marijuana: Craving, demand, and attentional bias.

PubMed

Metrik, Jane; Aston, Elizabeth R; Kahler, Christopher W; Rohsenow, Damaris J; McGeary, John E; Knopik, Valerie S; MacKillop, James

2016-10-01

Incentive salience is a multidimensional construct that includes craving, drug value relative to other reinforcers, and implicit motivation such as attentional bias to drug cues. Laboratory cue reactivity (CR) paradigms have been used to evaluate marijuana incentive salience with measures of craving, but not with behavioral economic measures of marijuana demand or implicit attentional processing tasks. This within-subjects study used a new CR paradigm to examine multiple dimensions of marijuana's incentive salience and to compare CR-induced increases in craving and demand. Frequent marijuana users (N=93, 34% female) underwent exposure to neutral cues then to lit marijuana cigarettes. Craving, marijuana demand via a marijuana purchase task, and heart rate were assessed after each cue set. A modified Stroop task with cannabis and control words was completed after the marijuana cues as a measure of attentional bias. Relative to neutral cues, marijuana cues significantly increased subjective craving and demand indices of intensity (i.e., drug consumed at $0) and Omax (i.e., peak drug expenditure). Elasticity significantly decreased following marijuana cues, reflecting sustained purchase despite price increases. Craving was correlated with demand indices (r's: 0.23-0.30). Marijuana users displayed significant attentional bias for cannabis-related words after marijuana cues. Cue-elicited increases in intensity were associated with greater attentional bias for marijuana words. Greater incentive salience indexed by subjective, behavioral economic, and implicit measures was observed after marijuana versus neutral cues, supporting multidimensional assessment. The study highlights the utility of a behavioral economic approach in detecting cue-elicited changes in marijuana incentive salience. Published by Elsevier Ireland Ltd.

Marijuana usage in relation to harmfulness ratings, perceived likelihood of negative consequences, and defense mechanisms in high school students.

PubMed

Como-Lesko, N; Primavera, L H; Szeszko, P R

1994-08-01

This study investigated high school students' marijuana usage patterns in relation to their harmfulness ratings of 15 licit and illicit drugs, perceived negative consequences from using marijuana, and types of defense mechanisms employed. Subjects were classified into one of five pattern-of-use groups based on marijuana usage: principled nonusers, nonusers, light users, moderate users, and heavy users. Principled nonusers (individuals who have never used marijuana and would not do so if it was legalized) rated marijuana, hashish, cocaine, and alcohol as significantly more harmful than heavy users. A cluster analysis of the drugs' harmfulness ratings best fit a three cluster solution and were named medicinal drugs, recreational drugs, and hard drugs. In general, principled nonusers rated negative consequences from using marijuana as significantly more likely to occur than other groups. Principled nonusers and heavy users utilized reversal from the Defense Mechanism Inventory, which includes repression and denial, significantly more than nonusers, indicating some trait common to the two extreme pattern-of-use groups.

Marijuana, alcohol, and drug impaired driving among emerging adults: Changes from high school to one-year post high school

PubMed Central

Li, Kaigang; Simons-Morton, Bruce; Gee, Benjamin; Hingson, Ralph

2016-01-01

Introduction Driving while impaired (DWI) increases the risk of a motor vehicle crash by impairing performance. Few studies have examined the prevalence and predictors of marijuana, alcohol, and drug specific DWI among emerging adults. Methods The data from wave 3 (W3, high-school seniors, 2012, N=2407) and wave 4 (W4, one year after high school, N=2178) of the NEXT Generation Health Study with a nationally-representative cohort. W4 DWI (≥1 day of past 30 days) was specified for alcohol-specific, marijuana-specific, alcohol/marijuana-combined, illicit drug-related DWI. Multinomial logistic regression models estimated the association of W4 DWI with W3 covariates (perceived peer/parent influence, drinking/binge drinking, marijuana/illicit drug use), and W4 environmental-status variables (work/school/residence) adjusting for W3 overall DWI, demographic and complex-survey variables. Results Overall DWI prevalence from W3 to W4 changed slightly (14% to 15%). W4 DWI consisted of 4.34% drinking-specific, 5.02% marijuana-specific, 2.41% drinking/marijuana-combined, and 3.37% illicit drug-related DWI. W3 DWI was significantly associated with W4 alcohol-related and alcohol/marijuana-combined DWI, but not other DWI. W3 marijuana use, binge drinking, and illicit drug use were positively associated with W4 marijuana-specific, alcohol/marijuana-combined, and illicit drug-related DWI respectively. W3 friend drunkenness and marijuana use were positively associated with W4 alcohol-specific and marijuana-related DWI respectively. W3 peer marijuana use was negatively associated with W4 alcohol-specific DWI. Conclusions Driving under the influence of alcohol, marijuana, and illicit drugs is a persistent, threatening public health concern among emerging US adults. High-school seniors’ binge drinking as well as regular alcohol drinking and marijuana/illicit drug use were independently associated with respective DWI one year after high school. Peer drunkenness and marijuana use in

Marijuana Neurobiology and Treatment

PubMed Central

Elkashef, Ahmed; Vocci, Frank; Huestis, Marilyn; Haney, Margaret; Budney, Alan; Gruber, Amanda; el-Guebaly, Nady

2008-01-01

Marijuana is the number one illicit drug of abuse worldwide and a major public health problem, especially in the younger population. The objective of this article is to update and review the state of the science and treatments available for marijuana dependence based on a pre-meeting workshop that was presented at ISAM 2006. At the workshop, several papers were presented addressing the neurobiology and pharmacology of marijuana and treatment approaches, both psychotherapy and medications, for marijuana withdrawal. Medicolegal and ethical issues concerning marijuana medical use were also discussed. Concise summaries of these presentations are incorporated in this article, which is meant to be an updated review of the state of the science. Major advances have been made in understanding the underpinning of marijuana dependence and the role of the CNS cannabinoid system, which is a major area for targeting medications to treat marijuana withdrawal and dependence, as well as other addictions. Behavioral therapies are efficacious for facilitating abstinence from marijuana. Nefazadone, Marinol, and buspirone are showing early positive signals for efficacy in ameliorating marijuana withdrawal symptoms. Effective psychotherapeutic approaches are available and promising medications studies need to be confirmed in outpatient trials. The next few years looking promising for translational research efforts to make treatment widely accessible to patients with marijuana dependence. PMID:19042204

Association of marijuana smoking with oropharyngeal and oral tongue cancers: pooled analysis from the INHANCE consortium.

PubMed

Marks, Morgan A; Chaturvedi, Anil K; Kelsey, Karl; Straif, Kurt; Berthiller, Julien; Schwartz, Stephen M; Smith, Elaine; Wyss, Annah; Brennan, Paul; Olshan, Andrew F; Wei, Qingyi; Sturgis, Erich M; Zhang, Zuo-Feng; Morgenstern, Hal; Muscat, Joshua; Lazarus, Philip; McClean, Michael; Chen, Chu; Vaughan, Thomas L; Wunsch-Filho, Victor; Curado, Maria Paula; Koifman, Sergio; Matos, Elena; Menezes, Ana; Daudt, Alexander W; Fernandez, Leticia; Posner, Marshall; Boffetta, Paolo; Lee, Yuan-Chin Amy; Hashibe, Mia; D'Souza, Gypsyamber

2014-01-01

The incidence of oropharyngeal and oral tongue cancers has increased over the last 20 years which parallels increased use of marijuana among individuals born after 1950. A pooled analysis was conducted comprising individual-level data from nine case-control studies from the United States and Latin America in the INHANCE consortium. Self-reported information on marijuana smoking, demographic, and behavioral factors was obtained from 1,921 oropharyngeal cases, 356 oral tongue cases, and 7,639 controls. Compared with never marijuana smokers, ever marijuana smokers had an elevated risk of oropharyngeal [adjusted OR (aOR), 1.24; 95% confidence interval (CI): 1.06-1.47] and a reduced risk of oral tongue cancer (aOR, 0.47; 95% CI, 0.29, 0.75). The risk of oropharyngeal cancer remained elevated among never tobacco and alcohol users. The risk of oral tongue cancer was reduced among never users of tobacco and alcohol. Sensitivity analysis adjusting for potential confounding by HPV exposure attenuated the association of marijuana use with oropharyngeal cancer (aOR, 0.99; 95% CI, 0.71-1.25), but had no effect on the oral tongue cancer association. These results suggest that the association of marijuana use with head and neck carcinoma may differ by tumor site. The associations of marijuana use with oropharyngeal and oral tongue cancer are consistent with both possible pro- and anticarcinogenic effects of cannabinoids. Additional work is needed to rule out various sources of bias, including residual confounding by HPV infection and misclassification of marijuana exposure.

Being Blunt About Marijuana: Parent Communication About Marijuana with Their Emerging Adult Children

PubMed Central

Froidevaux, Nicole M.; LaBrie, Joseph W.

2016-01-01

While research suggests that parents continue to influence students’ marijuana use after matriculation to college, there is limited data examining how parents communicate about marijuana use and what impact parent marijuana communication has on college student outcomes. The aim of the current study is to investigate the types of parent marijuana messages that college students receive and the relationship between parent communication and students’ marijuana attitudes and behaviors. Students (N = 506) completed a survey assessing marijuana approval, use, negative consequences, and parent communication. A factor analysis of parent communication items yielded three factors: risk communication, permissive communication, and marijuana use communication. Risk communication was the most common form of communication. In multivariate models, risk communication was associated with increased odds of a student remaining abstinent but not with frequency of marijuana use or negative consequences. Greater permissive communication was associated with more approving student attitudes, greater odds of non-abstinence, more frequent use in the past year, and more negative consequences. These findings highlight the need to consider the different types of messages parents deliver when designing interventions aimed at engaging parents in marijuana prevention efforts. PMID:27438296

Teen Use of Marijuana Edibles: A Focus Group Study of an Emerging Issue.

PubMed

Friese, Bettina; Slater, Michael D; Annechino, Rachelle; Battle, Robynn S

2016-06-01

Recent research indicates that marijuana-infused food product (i.e., edible) use is becoming nearly as common as smoking marijuana where medical marijuana is available. This study explores edible use among teens. We conducted four focus groups in the San Francisco Bay Area with youth, ages 15-17. The focus groups were divided by gender and whether they used marijuana. Some teens mentioned edible use at school. Youth reported that teens consume edibles, primarily to reduce the likelihood of getting caught. Edibles are also attractive to those who do not like to smoke or have concerns about smoking. Both male and female respondents suggested that females are more likely than males to prefer edibles over smoking, one reason for which may be to avoid smelling like marijuana smoke. For some young women, edibles may be a way to avoid publicly presenting themselves as marijuana users. Findings also suggest that youth have access to edibles through multiple sources. Youth reported that they can purchase edibles at school from other students who either make the edibles themselves or are reselling edibles obtained from dispensaries. Both users and non-users were aware of potentially negative consequences related to edible use. Some youth mentioned that they have heard of youth dying from edibles, and several reported being concerned about the high produced by edibles. Female non-users appeared to be more concerned than others about edibles and compared them to drinks that could be spiked with drugs. However, sentiment among some male marijuana users was that if you cannot handle edibles you should not be using them. These findings suggest that strategies to curb access to edibles and use among youth, such as restricting sales of edibles with strong youth appeal and educating youth on the risks of edibles, will need to be developed.

Teen Use of Marijuana Edibles: A Focus Group Study of an Emerging Issue

PubMed Central

Friese, Bettina; Slater, Michael D.; Annechino, Rachelle; Battle, Robynn S.

2016-01-01

Recent research indicates that marijuana-infused food product (i.e., edible) use is becoming nearly as common as smoking marijuana where medical marijuana is available. This study explores edible use among teens. We conducted four focus groups in the San Francisco Bay Area with youth, ages 15-17. The focus groups were divided by gender and whether they used marijuana. Some teens mentioned edible use at school. Youth reported that teens consume edibles, primarily to reduce the likelihood of getting caught. Edibles are also attractive to those who do not like to smoke or have concerns about smoking. Both male and female respondents suggested that females are more likely than males to prefer edibles over smoking, one reason for which may be to avoid smelling like marijuana smoke. For some young women, edibles may be a way to avoid publicly presenting themselves as marijuana users. Findings also suggest that youth have access to edibles through multiple sources. Youth reported that they can purchase edibles at school from other students who either make the edibles themselves or are reselling edibles obtained from dispensaries. Both users and non-users were aware of potentially negative consequences related to edible use. Some youth mentioned that they have heard of youth dying from edibles, and several reported being concerned about the high produced by edibles. Female non-users appeared to be more concerned than others about edibles and compared them to drinks that could be spiked with drugs. However, sentiment among some male marijuana users was that if you cannot handle edibles you should not be using them. These findings suggest that strategies to curb access to edibles and use among youth, such as restricting sales of edibles with strong youth appeal and educating youth on the risks of edibles, will need to be developed. PMID:27056685

EXAMINING THE RELATIONSHIP BETWEEN THE PHYSICAL AVAILABILITY OF MEDICAL MARIJUANA AND MARIJUANA USE ACROSS FIFTY CALIFORNIA CITIES

PubMed Central

Freisthler, Bridget; Gruenewald, Paul J.

2014-01-01

Background The purpose of the current study is to assess statistical associations between individual demographic and personality characteristics, the city-level physical availability of medical marijuana (as measured through densities per roadway mile of storefront dispensaries and delivery services), and the incidence and prevalence of marijuana use. Method Individual level data on marijuana use were collected during a telephone survey of 8,853 respondents living in 50 mid-size cities in California. Data on medical marijuana dispensaries and delivery services were obtained via six different websites and official city lists. Three outcome variables pertaining to lifetime, past year use, and frequency of past year use were analyzed using random effects logistic models (for lifetime and past year use) and random effects tobit models (for frequency of past 365-day use). Results The current study finds that the total physical availability of medical marijuana through dispensaries and delivery services per roadway mile at the city-level is positively related to current marijuana use and greater frequency of use, controlling for a variety of demographic and personality characteristics. As expected, current physical availability of medical marijuana was unrelated to lifetime use. Conclusions Regulations on the number and densities of marijuana outlets may be a sufficient means to restrain overall levels of marijuana use within cities. However, alternative use of delivery services may also provide easy access to marijuana and mitigate these effects. PMID:25156224

Examining the relationship between the physical availability of medical marijuana and marijuana use across fifty California cities.

PubMed

Freisthler, Bridget; Gruenewald, Paul J

2014-10-01

The purpose of the current study is to assess statistical associations between individual demographic and personality characteristics, the city-level physical availability of medical marijuana (as measured through densities per roadway mile of storefront dispensaries and delivery services), and the incidence and prevalence of marijuana use. Individual level data on marijuana use were collected during a telephone survey of 8853 respondents living in 50 mid-size cities in California. Data on medical marijuana dispensaries and delivery services were obtained via six different websites and official city lists. Three outcome variables pertaining to lifetime, past year use, and frequency of past year use were analyzed using random effects logistic models (for lifetime and past year use) and random effects tobit models (for frequency of past 365-day use). The current study finds that the total physical availability of medical marijuana through dispensaries and delivery services per roadway mile at the city-level is positively related to current marijuana use and greater frequency of use, controlling for a variety of demographic and personality characteristics. As expected, current physical availability of medical marijuana was unrelated to lifetime use. Regulations on the number and densities of marijuana outlets may be a sufficient means to restrain overall levels of marijuana use within cities. However, alternative use of delivery services may also provide easy access to marijuana and mitigate these effects. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Changes in Attitudes, Intentions, and Behaviors toward Tobacco and Marijuana during U.S. Students' First Year of College.

PubMed

Stewart, Mara W; Moreno, Megan A

2013-04-16

Tobacco and marijuana are commonly used by college students and have negative health effects. The purpose of the study was to understand how students' attitudes, intentions, and behaviors toward tobacco and marijuana change during freshman year and to examine how attitude and intention predict use of these substances. College students completed phone interviews before and after freshman year. The identical interviews assessed students' attitudes, intentions, and behaviors toward both substances. Attitude was measured on a 0-6 scale (6 = most positive), intention on a 0-5 scale (5 = very likely to use), and behavior by lifetime use (yes or no) and current use (past-28-days). Overall, 275 participants completed both interviews. Attitudes increased (tobacco 0.9 to 1.2, p < 0.01; marijuana 1.9 to 2.3, p < 0.01). Intentions increased (tobacco 0.4 to 0.8, p = 0.03; marijuana 0.7 to 1.1, p < 0.01). 12.2% initiated tobacco, 13.5% initiated marijuana. Only intention predicted tobacco initiation, while both attitude and intention predicted marijuana initiation. Attitudes, intentions, and behaviors changed significantly towards favored use. Predictors of use varied by substance, suggesting that different prevention approaches may be beneficial.

Mediating processes between stress and problematic marijuana use.

PubMed

Ketcherside, Ariel; Filbey, Francesca M

2015-06-01

The literature widely reports that stress is associated with marijuana use, yet, to date, the path from stress to marijuana-related problems has not been tested. In this study, we evaluated whether negative affect mediates the relationship between stress and marijuana use. To that end, we tested models to determine mediators between problems with marijuana use (via Marijuana Problem Scale), stress (via Early Life Stress Questionnaire, Perceived Stress Scale), and negative affect (via Beck Depression Inventory; Beck Anxiety Inventory) in 157 current heavy marijuana users. Mediation tests and bootstrap confidence intervals were carried out via the "Mediation" package in R. Depression and anxiety scores both significantly mediated the relationship between perceived stress and problematic marijuana use. Only depression significantly mediated the relationship between early life stress and problematic marijuana use. Early life stress, perceived stress and problematic marijuana use were significant only as independent variables and dependent variables. These findings demonstrate that (1) depression mediated both early life stress and perceived stress, and problematic marijuana use, and, (2) anxiety mediated perceived stress and problematic marijuana use. This mediation analysis represents a strong first step toward understanding the relationship between these variables; however, longitudinal studies are needed to determine causality between these variables. To conclude, addressing concomitant depression and anxiety in those who report either perceived stress or early life stress is important for the prevention of cannabis use disorders. Copyright © 2015. Published by Elsevier Ltd.

Recreational marijuana use and acute ischemic stroke: A population-based analysis of hospitalized patients in the United States.

PubMed

Rumalla, Kavelin; Reddy, Adithi Y; Mittal, Manoj K

2016-05-15

Recreational marijuana use is considered to have few adverse effects. However, recent evidence has suggested that it precipitates cardiovascular and cerebrovascular events. Here, we investigated the relationship between marijuana use and hospitalization for acute ischemic stroke (AIS) using data from the largest inpatient database in the United States. The Nationwide Inpatient Sample was queried from 2004 to 2011 for all patients (age 15-54) with a primary diagnosis of AIS. The incidence of AIS hospitalization in marijuana users and non-marijuana users was determined. We utilized multivariable logistic regression analyses to study the independent association between marijuana use and AIS. Overall, the incidence of AIS was significantly greater among marijuana users compared to non-users (Relative Risk [RR]: 1.13, 95% CI: 1.11-1.15, P<0.0001) and had the greatest difference in the 25-34 age group (RR: 2.26, 95% CI: 2.13-2.38, P<0.0001). Marijuana use was more prevalent among younger patients, males, African Americans, and Medicaid enrollees (P<0.0001). Marijuana users were more likely to use other illicit substances but had less overall medical comorbidity. In multivariable analysis, adjusted for potential confounders, marijuana (Odds Ratio [OR]: 1.17, 95% CI: 1.15-1.20), tobacco (OR: 1.76, 95% CI: 1.74-1.77), cocaine (OR: 1.32, 95% CI: 1.30-1.34), and amphetamine (OR: 2.21, 95% CI: 2.12-2.30) usage were found to increase the likelihood of AIS (all P<0.0001). Among younger adults, recreational marijuana use is independently associated with 17% increased likelihood of AIS hospitalization. Copyright © 2016 Elsevier B.V. All rights reserved.

Changes in Attitudes, Intentions, and Behaviors toward Tobacco and Marijuana during U.S. Students’ First Year of College

PubMed Central

Stewart, Mara W; Moreno, Megan A

2013-01-01

Tobacco and marijuana are commonly used by college students and have negative health effects. The purpose of this study was to understand how students’ attitudes, intentions, and behaviors toward tobacco and marijuana change during freshman year and to examine how attitude and intention predict use of these substances. 275 college students completed phone interviews before and after their freshman year. The identical interviews assessed students’ attitudes, intentions, and behaviors toward both substances. Attitudes and intentions increased significantly. 12.2% of participants initiated tobacco use and 13.5% initiated marijuana use. Only intention predicted tobacco initiation, while both attitude and intention predicted marijuana initiation. Overall, attitudes, intentions, and behaviors changed significantly toward favored use. Predictors of use varied by substance, suggesting that different prevention approaches may be beneficial. PMID:24761133

A dimensional approach to understanding severity estimates and risk correlates of marijuana abuse and dependence in adults

PubMed Central

WU, LI-TZY; WOODY, GEORGE E.; YANG, CHONGMING; PAN, JENG-JONG; REEVE, BRYCE B.; BLAZER, DAN G.

2012-01-01

While item response theory (IRT) research shows a latent severity trait underlying response patterns of substance abuse and dependence symptoms, little is known about IRT-based severity estimates in relation to clinically relevant measures. In response to increased prevalences of marijuana-related treatment admissions, an elevated level of marijuana potency, and the debate on medical marijuana use, we applied dimensional approaches to understand IRT-based severity estimates for marijuana use disorders (MUDs) and their correlates while simultaneously considering gender- and race/ethnicity-related differential item functioning (DIF). Using adult data from the 2008 National Survey on Drug Use and Health (N=37,897), DSM-IV criteria for MUDs among past-year marijuana users were examined by IRT, logistic regression, and multiple indicators–multiple causes (MIMIC) approaches. Among 6,917 marijuana users, 15% met criteria for a MUD; another 24% exhibited subthreshold dependence. Abuse criteria were highly correlated with dependence criteria (correlation=0.90), indicating unidimensionality; item information curves revealed redundancy in multiple criteria. MIMIC analyses showed that MUD criteria were positively associated with weekly marijuana use, early marijuana use, other substance use disorders, substance abuse treatment, and serious psychological distress. African Americans and Hispanics showed higher levels of MUDs than whites, even after adjusting for race/ethnicity-related DIF. The redundancy in multiple criteria suggests an opportunity to improve efficiency in measuring symptom-level manifestations by removing low-informative criteria. Elevated rates of MUDs among African Americans and Hispanics require research to elucidate risk factors and improve assessments of MUDs for different racial/ethnic groups. PMID:22351489

Cue-Elicited Increases in Incentive Salience for Marijuana: Craving, Demand, and Attentional Bias

PubMed Central

Metrik, Jane; Aston, Elizabeth R.; Kahler, Christopher W.; Rohsenow, Damaris J.; McGeary, John E.; Knopik, Valerie S.; MacKillop, James

2016-01-01

Background Incentive salience is a multidimensional construct that includes craving, drug value relative to other reinforcers, and implicit motivation such as attentional bias to drug cues. Laboratory cue reactivity (CR) paradigms have been used to evaluate marijuana incentive salience with measures of craving, but not with behavioral economic measures of marijuana demand or implicit attentional processing tasks. Methods This within-subjects study used a new CR paradigm to examine multiple dimensions of marijuana’s incentive salience and to compare CR-induced increases in craving and demand. Frequent marijuana users (N=93, 34% female) underwent exposure to neutral cues then to lit marijuana cigarettes. Craving, marijuana demand via a marijuana purchase task, and heart rate were assessed after each cue set. A modified Stroop task with cannabis and control words was completed after the marijuana cues as a measure of attentional bias. Results Relative to neutral cues, marijuana cues significantly increased subjective craving and demand indices of intensity (i.e., drug consumed at $0) and Omax (i.e., peak drug expenditure). Elasticity significantly decreased following marijuana cues, reflecting sustained purchase despite price increases. Craving was correlated with demand indices (r’s: 0.23–0.30). Marijuana users displayed significant attentional bias for cannabis-related words after marijuana cues. Cue-elicited increases in intensity were associated with greater attentional bias for marijuana words. Conclusions Greater incentive salience indexed by subjective, behavioral economic, and implicit measures was observed after marijuana versus neutral cues, supporting multidimensional assessment. The study highlights the utility of a behavioral economic approach in detecting cue-elicited changes in marijuana incentive salience. PMID:27515723

Marijuana policy opinions in Washington state since legalization: Would voters vote the same way?

PubMed

Subbaraman, Meenakshi Sabina; Kerr, William C

2016-12-01

In 2012, voters in Washington state approved Initiative 502 (I-502) which legalized recreational marijuana use at the state level. This study examines the relationship between demographics, marijuana and alcohol use, and voting outcomes, as well as how these variables relate to (i) whether voters would still vote the same way (a reflection of satisfaction with the new policy) and (ii) the likelihood of using marijuana purchased from legal retail stores. The sample consists of 2,007 adult Washington state residents recruited through Random Digit Dial between January and October 2014. Bivariate tests and multivariable regressions were used for analyses. Less than five percent of those who voted for marijuana legalization would change their votes, whereas 14% of those who voted against legalization would change their votes. In multivariable models controlling for demographics, substance use, and marijuana-related opinions, those who voted for legalization had half the odds of changing their votes than those who voted against it. Among past-year non-marijuana users, almost 10% were somewhat/very likely to use marijuana if they could buy it from a legal store. Past marijuana use, the belief that adults should be allowed to grow marijuana for personal use, and the belief that marijuana is not very risky for health were all related to increased likelihood of using marijuana purchased from legal stores. Since November 2012, support for marijuana legalization in Washington state has increased; accounting for the proportion of voters who would change their votes suggests that I-502 would pass today with even more votes in favor.

The couple that smokes together: Dyadic marijuana use and relationship functioning during conflict.

PubMed

Crane, Cory A; Testa, Maria; Schlauch, Robert C; Leonard, Kenneth E

2016-09-01

Self-reported marijuana use has been associated with poor relationship functioning and decreased stability over time. The present study examined the behavioral interactions of couples with concordant and discordant patterns of marijuana use during conflict, using individual self-reports and observation by independent coders. Heavy drinking community couples (N = 149) participated in a conflict resolution paradigm. Interactions were recorded and coded by naïve coders. Approximately 30% of the sample reported past year marijuana use. Actor-Partner Interdependence Models and analysis of covariance (ANCOVA) were used to evaluate the individual and interactive effects of dyadic marijuana use on maladaptive relationship functioning. A Robust Actor × Partner Marijuana Use interaction was detected for a range of behavioral outcomes, assessed by both self-report and direct observation, including relationship satisfaction, anger experience, patterns of demand and withdrawal during conflict, constructive behaviors, and overall relationship quality. Specifically, couples in which both partners used or abstained from marijuana displayed more adaptive relationship functioning across indicators relative to couples in which only 1 partner identified as a marijuana user. This pattern was particularly strong for couples in which the female partner used marijuana and the male partner did not. Couples with discordant, rather than concordant, marijuana use displayed distinct conflict resolution behaviors that were consistent with the long-term negative relationship outcomes that have been observed in previous studies. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A study investigating the acute dose-response effects of 13 mg and 17 mg Delta 9- tetrahydrocannabinol on cognitive-motor skills, subjective and autonomic measures in regular users of marijuana.

PubMed

Weinstein, A; Brickner, O; Lerman, H; Greemland, M; Bloch, M; Lester, H; Chisin, R; Sarne, Y; Mechoulam, R; Bar-Hamburger, R; Freedman, N; Even-Sapir, E

2008-06-01

Heavy use of marijuana is claimed to damage critical skills related to short-term memory, visual scanning and attention. Motor skills and driving safety may be compromised by the acute effects of marijuana. The aim of this study was to investigate the acute effects of 13 mg and 17 mg Delta 9-tetrahydrocannabinol (THC) on skills important for coordinated movement and driving and on subjective and autonomic measures in regular users of marijuana. Fourteen regular users of marijuana were enrolled. Each subject was tested on two separate days. On each test day, subjects smoked two low-nicotine cigarettes, one with and the other without THC. Seventeen mg THC was included in the cigarette on one test day and 13 mg on the other day. The sequence of cigarette types was unknown to the subject. During smoking, heart rate and blood pressure were monitored, and the subjects performed a virtual reality maze task requiring attention and motor coordination, followed by 3 other cognitive tasks (Wisconsin Card Sorting Test (WCST), a "gambling" task and estimation of time and distance from an approaching car). After smoking a cigarette with 17 mg THC, regular marijuana users hit the walls more often on the virtual maze task than after smoking cigarettes without THC; this effect was not seen in patients after they smoked cigarettes with 13 mg THC. Performance in the WCST was affected with 17 mg THC and to a lesser extent with the use of 13 mg THC. Decision making in the gambling task was affected after smoking cigarettes with 17 mg THC, but not with 13 m THC. Smoking cigarettes with 13 and 17 mg THC increased subjective ratings of pleasure and satisfaction, drug "effect" and drug "high". These findings imply that smoking of 17 mg THC results in impairment of cognitive-motor skills that could be important for coordinated movement and driving, whereas the lower dose of 13 mg THC appears to cause less impairment of such skills in regular users of marijuana.

Medical Marijuana programs: implications for cannabis control policy--observations from Canada.

PubMed

Fischer, Benedikt; Kuganesan, Sharan; Room, Robin

2015-01-01

While prohibition has been the dominant regime of cannabis control in most countries for decades, an increasing number of countries have been implementing cannabis control reforms recently, including decriminalization or even legalization frameworks. Canada has held out from this trend, although it has among the highest cannabis use rates in the world. Cannabis use is universally criminalized, and the current (conservative) federal government has vowed not to implement any softening reforms to cannabis control. As a result of several higher court decisions, the then federal government was forced to implement a 'medical marijuana access regulations' program in 2001 to allow severely ill patients therapeutic use and access to therapeutic cannabis while shielding them from prosecution. The program's regulations and approval processes were complex and subject to extensive criticism; initial uptake was low and most medical marijuana users continued their use and supply outside the program's auspices. This year, the government introduced new 'marijuana for medical purposes regulations', which allow physicians to 'authorize' medical marijuana use for virtually any health condition for which this is considered beneficial; supply is facilitated by licensed commercial producers. It is expected that some 500,000 users, and dozens of commercial producers will soon be approved under the program, arguably constituting - as with medical marijuana schemes elsewhere, e.g. in California--de facto 'legalization'. We discuss the question whether the evolving scope and realities of 'medical cannabis' provisions in Canada offer a 'sneaky side door' or a 'better third way' to cannabis control reform, and what the potential wider implications are of these developments. Copyright © 2014. Published by Elsevier B.V.

Effectiveness of a Marijuana Expectancy Manipulation: Piloting the Balanced-Placebo Design for Marijuana

PubMed Central

Metrik, Jane; Rohsenow, Damaris J.; Monti, Peter M.; McGeary, John; Cook, Travis A. R.; de Wit, Harriet; Haney, Margaret; Kahler, Christopher W.

2009-01-01

Although alcohol and nicotine administration studies have demonstrated that manipulating subjects’ expectancies regarding drug content affects drug response, research with marijuana has not adequately studied drug expectancy effects. The present pilot study was the first to evaluate the credibility and effect of expectancy manipulation on subjective measures and smoking patterns using a marijuana administration balanced-placebo design (BPD). In a 2 × 2 instructional set (told delta-9-tetrahydrocannabinol [THC] vs. told no THC) by drug (smoked marijuana with 2.8% THC vs. placebo) between-subjects design, the authors examined the effect of marijuana expectancy manipulation and the pharmacologic effect on affective and physiologic measures, cigarette ratings, and smoking behavior with 20 marijuana smokers (mean age = 20 years; 25% female). Large main effects of expectancy were found on ratings of cigarette potency, strength, taste, smell, and satisfaction, and observed smoking behavior. Pharmacologic effects were particularly evident for self-reported physical reactions to marijuana and cigarette potency and satisfaction ratings. This study demonstrated the feasibility of the BPD research with marijuana and yielded promising results for future studies examining the independent and combined effects of marijuana pharmacology and expectancies. PMID:19653787

Marijuana use and service utilization among adolescents 7 years post substance use treatment.

PubMed

Campbell, Cynthia I; Sterling, Stacy; Chi, Felicia W; Kline-Simon, Andrea H

2016-11-01

In an environment of increasingly liberal attitudes towards marijuana use and legalization, little is known about long-term trajectories of marijuana use among clinical samples of adolescents, and how these trajectories relate to health services utilization over time. Latent growth curve analysis was used to identify distinct trajectories of marijuana use in a clinical sample of adolescents (N=391) over 7 years post substance use treatment in an integrated health system. We examined psychiatric problems and polysubstance use associated with the identified trajectory groups using general linear models. Nonlinear mixed-effects logistic regressions were used to examine associations between health services use and the trajectory groups. We identified three marijuana use trajectory groups: (1) Abstinent (n=117); (2) Low/Stable use (n=174); and (3) Increasing use (n=100). Average externalizing and anxiety/depression scores were significantly lower over time for the Abstinent group compared to the Increasing and Low/Stable groups. The Low Stable and the Increasing group had fewer psychiatric visits over time (p<0.05) and the Low/Stable group used more substance use treatment services over time compared with the Abstinent group (p<0.001). Treated adolescents showed distinct marijuana use patterns, one of which indicated a group of adolescents at risk of increased use over time. These individuals have greater psychiatric and polysubstance use over time, but may not be accessing needed services. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Interrelationships between Marijuana Demand and Discounting of Delayed Rewards: Convergence in Behavioral Economic Methods

PubMed Central

Aston, Elizabeth R.; Metrik, Jane; Amlung, Michael; Kahler, Christopher W.; MacKillop, James

2016-01-01

Background Distinct behavioral economic domains, including high perceived drug value (demand) and delay discounting (DD), have been implicated in the initiation of drug use and the progression to dependence. However, it is unclear whether frequent marijuana users conform to a “reinforcer pathology” addiction model wherein marijuana demand and DD jointly increase risk for problematic marijuana use and cannabis dependence (CD). Methods Participants (n=88, 34% female, 14% cannabis dependent) completed a marijuana purchase task at baseline. A delay discounting task was completed following placebo marijuana cigarette (0% THC) administration during a separate experimental session. Results Marijuana demand and DD were quantified using area under the curve (AUC). In multiple regression models, demand uniquely predicted frequency of marijuana use while DD did not. In contrast, DD uniquely predicted CD symptom count while demand did not. There were no significant interactions between demand and DD in either model. Conclusions These findings suggest that frequent marijuana users exhibit key constituents of the reinforcer pathology model: high marijuana demand and steep discounting of delayed rewards. However, demand and DD appear to be independent rather than synergistic risk factors for elevated marijuana use and risk for progression to CD. Findings also provide support for using AUC as a singular marijuana demand metric, particularly when also examining other behavioral economic constructs that apply similar statistical approaches, such as DD, to support analytic methodological convergence. PMID:27810657

Perceptions of Social Norms and Exposure to Pro-Marijuana Messages Are Associated with Adolescent Marijuana Use

PubMed Central

Roditis, Maria L.; Delucchi, Kevin; Chang, Audrey; Halpern-Felsher, Bonnie

2016-01-01

Despite consistent declines in rates of cigarette use among adolescents in the last five years, rates of marijuana use have remained constant, with marijuana being the most widely used illegal drug among adolescents. More work is needed to understand how social norms, perceived risks and benefits, and social media messaging impact use of marijuana. This study compared perceptions and social norms related to marijuana, blunts and cigarettes. Additionally, we assessed how perceptions related to social norms, risks and benefits, and exposure to pro- versus anti-marijuana messaging is related to use. Participants were 786 adolescents from Southern and Northern California (36.7% male, 63.3% females; mean age = 16.1 years; SD = 1.6). Participants came from diverse ethnic backgrounds, with 207 (26.61%) White, 171 (21.98%) Asian/Pacific Islander, 232 (29.82%) Hispanic, and 168 (21.59%) other. Results indicated that marijuana and blunts were consistently perceived as more socially acceptable and less risky than cigarettes (p<0.01). Participants who reported that their friends used marijuana had a 27% greater odds of using marijuana themselves. Further, seeing messages about the good things or benefits of marijuana use was associated with a 6% greater odds of use [OR 1.06 (CI 1.00, 1.12)]. This study's findings offer a number of important public health implications, particularly as states move towards legalization of marijuana for recreational use. As this occurs, states need to take adolescents’ perceptions of risks, benefits, social norms, and peer influences into account as they implement strategies to reduce youth use of marijuana and blunts. PMID:27746339

Brain activation to negative stimuli mediates a relationship between adolescent marijuana use and later emotional functioning.

PubMed

Heitzeg, Mary M; Cope, Lora M; Martz, Meghan E; Hardee, Jillian E; Zucker, Robert A

2015-12-01

This work investigated the impact of heavy marijuana use during adolescence on emotional functioning, as well as the brain functional mediators of this effect. Participants (n=40) were recruited from the Michigan Longitudinal Study (MLS). Data on marijuana use were collected prospectively beginning in childhood as part of the MLS. Participants were classified as heavy marijuana users (n=20) or controls with minimal marijuana use. Two facets of emotional functioning-negative emotionality and resiliency (a self-regulatory mechanism)-were assessed as part of the MLS at three time points: mean age 13.4, mean age 19.6, and mean age 23.1. Functional neuroimaging data during an emotion-arousal word task were collected at mean age 20.2. Negative emotionality decreased and resiliency increased across the three time points in controls but not heavy marijuana users. Compared with controls, heavy marijuana users had less activation to negative words in temporal, prefrontal, and occipital cortices, insula, and amygdala. Activation of dorsolateral prefrontal cortex to negative words mediated an association between marijuana group and later negative emotionality. Activation of the cuneus/lingual gyrus mediated an association between marijuana group and later resiliency. Results support growing evidence that heavy marijuana use during adolescence affects later emotional outcomes. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Marijuana: A Realistic Approach

PubMed Central

Chun, George

1971-01-01

Much of the current confusion concerning marijuana has been caused by a lack of definition of terms. Variations in drug effect that are related to the type and potency of cannabis preparation and route of administration need clarification. When domestic strength marijuana is smoked recreationally, the subjective effects include relaxation, mild euphoria and increased sensory awareness. The objective effects include tachycardia, reddening of the conjunctivae and a distorted sense of time. Undesirable effects such as panic reactions, amotivational behavior, and acute toxic psychosis occur infrequently and are reversible with proper therapy. Other effects which have been attributed to marijuana are unsubstantiated. The recent upsurge in use of marijuana involves persons of a different type than those who used it heretofore and has greatly increased the number of people familiar with the drug. The disparity between what many people know empirically and the information disseminated through official media has lessened the credibility of physicians with many of our younger citizens. When young people recognize misinformation about marijuana, they are no longer listening when the facts are presented about more dangerous drugs, and the abuse of these drugs must be our main concern. To be considered is the potential hazard to adolescent users who may concomitantly be exposed to a subculture of experimentation with stronger drugs at a time when the opinion of a peer group is a strong factor in their behavior. PMID:5551311

Marijuana use/cessation expectancies and marijuana use in college students

PubMed Central

Brackenbury, Lauren M.; Ladd, Benjamin O.; Anderson, Kristen G.

2016-01-01

Background Research suggests that marijuana expectancies are associated with problematic marijuana use; however, these marijuana-related cognitions remain relatively understudied. Objective This study examined marijuana-related decision-making among college students by exploring the relationships among marijuana expectancies and marijuana use variables. Method College students (N = 357) endorsing lifetime marijuana use completed an online survey on marijuana use expectancies, marijuana cessation expectancies, marijuana use, and future marijuana use intentions. A simple regression framework was used to test the effect of each type of expectancies on marijuana outcome; a hierarchical regression framework tested the unique predictive validity when both types were entered into the same model. Results Both marijuana use expectancies and marijuana cessation expectancies independently predicted a number of marijuana use variables. Additionally, marijuana use expectancies and marijuana cessation expectancies contributed significant unique variance to the prediction of marijuana use. Conclusions It is important to consider both use expectancies and cessation expectancies, as these two domains of marijuana-related cognitions appear to act independently, rather than as opposite ends of the same construct. Longitudinal studies are needed to further examine how these factors interact to influence marijuana use and problems over time. PMID:26678375

Poor decision-making by chronic marijuana users is associated with decreased functional responsiveness to negative consequences.

PubMed

Wesley, Michael J; Hanlon, Colleen A; Porrino, Linda J

2011-01-30

Chronic marijuana users (MJ Users) perform poorly on the Iowa Gambling Task (IGT), a complex decision-making task in which monetary wins and losses guide strategy development. This functional magnetic resonance imaging (MRI) study sought to determine if the poor performance of MJ Users was related to differences in brain activity while evaluating wins and losses during the strategy development phase of the IGT. MJ Users (16) and Controls (16) performed a modified IGT in an MRI scanner. Performance was tracked and functional activity in response to early wins and losses was examined. While the MJ Users continued to perform poorly at the end of the task, there was no difference in group performance during the initial strategy development phase. During this phase, before the emergence of behavioral differences, Controls exhibited significantly greater activity in response to losses in the anterior cingulate cortex, medial frontal cortex, precuneus, superior parietal lobe, occipital lobe and cerebellum as compared to MJ Users. Furthermore, in Controls, but not MJ Users, the functional response to losses in the anterior cingulate cortex, ventral medial prefrontal cortex and rostral prefrontal cortex positively correlated with performance over time. These data suggest MJ Users are less sensitive to negative feedback during strategy development. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

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…

Perceptions of social norms and exposure to pro-marijuana messages are associated with adolescent marijuana use.

PubMed

Roditis, Maria L; Delucchi, Kevin; Chang, Audrey; Halpern-Felsher, Bonnie

2016-12-01

Despite consistent declines in rates of cigarette use among adolescents in the last five years, rates of marijuana use have remained constant, with marijuana being the most widely used illegal drug among adolescents. More work is needed to understand how social norms, perceived risks and benefits, and social media messaging impact use of marijuana. This study compared perceptions and social norms related to marijuana, blunts and cigarettes. Additionally, we assessed how perceptions related to social norms, risks and benefits, and exposure to pro- versus anti-marijuana messaging is related to use. Participants were 786 adolescents from Southern and Northern California (36.7% male, 63.21% females; mean age=16.1years; SD=1.6). Participants came from diverse ethnic backgrounds, with 207 (26.61%) White, 171 (21.98%) Asian/Pacific Islander, 232 (29.82%) Hispanic, and 168 (21.59%) other. Results indicated that marijuana and blunts were consistently perceived as more socially acceptable and less risky than cigarettes (p<0.01). Participants who reported that their friends used marijuana had a 27% greater odds of using marijuana themselves. Further, seeing messages about the good things or benefits of marijuana use was associated with a 6% greater odds of use [OR 1.06 (CI 1.00, 1.12)]. This study's findings offer a number of important public health implications, particularly as states move towards legalization of marijuana for recreational use. As this occurs, states need to take adolescents' perceptions of risks, benefits, social norms, and peer influences into account as they implement strategies to reduce youth use of marijuana and blunts. Copyright © 2016 Elsevier Inc. All rights reserved.

Recreational marijuana use impacts white matter integrity and subcortical (but not cortical) morphometry.

PubMed

Orr, Joseph M; Paschall, Courtnie J; Banich, Marie T

2016-01-01

A recent shift in legal and social attitudes toward marijuana use has also spawned a surge of interest in understanding the effects of marijuana use on the brain. There is considerable evidence that an adolescent onset of marijuana use negatively impacts white matter coherence. On the other hand, a recent well-controlled study demonstrated no effects of marijuana use on the morphometry of subcortical or cortical structures when users and non-users were matched for alcohol use. Regardless, most studies have involved small, carefully selected samples, so the ability to generalize to larger populations is limited. In an attempt to address this issue, we examined the effects of marijuana use on white matter integrity and cortical and subcortical morphometry using data from the Human Connectome Project (HCP) consortium. The HCP data consists of ultra-high resolution neuroimaging data from a large community sample, including 466 adults reporting recreational marijuana use. Rather than just contrasting two groups of individuals who vary significantly in marijuana usage as typifies prior studies, we leveraged the large sample size provided by the HCP data to examine parametric effects of recreational marijuana use. Our results indicate that the earlier the age of onset of marijuana use, the lower was white matter coherence. Age of onset also also affected the shape of the accumbens, while the number of lifetime uses impacted the shape of the amygdala and hippocampus. Marijuana use had no effect on cortical volumes. These findings suggest subtle but significant effects of recreational marijuana use on brain structure.

Unintentional Pediatric Exposures to Marijuana in Colorado, 2009-2015.

PubMed

Wang, George Sam; Le Lait, Marie-Claire; Deakyne, Sara J; Bronstein, Alvin C; Bajaj, Lalit; Roosevelt, Genie

2016-09-06

As of 2015, almost half of US states allow medical marijuana, and 4 states allow recreational marijuana. To our knowledge, the effect of recreational marijuana on the pediatric population has not been evaluated. To compare the incidence of pediatric marijuana exposures evaluated at a children's hospital and regional poison center (RPC) in Colorado before and after recreational marijuana legalization and to compare population rate trends of RPC cases for marijuana exposures with the rest of the United States. Retrospective cohort study of hospital admissions and RPC cases between January 1, 2009, and December 31, 2015, at Children's Hospital Colorado, Aurora, a tertiary care children's hospital. Participants included patients 0 to 9 years of age evaluated at the hospital's emergency department, urgent care centers, or inpatient unit and RPC cases from Colorado for single-substance marijuana exposures. Marijuana. Marijuana exposure visits and RPC cases, marijuana source and type, clinical effects, scenarios, disposition, and length of stay. Eighty-one patients were evaluated at the children's hospital, and Colorado's RPC received 163 marijuana exposure cases between January 1, 2009, and December 31, 2015, for children younger than 10 years of age. The median age of children's hospital visits was 2.4 years (IQR, 1.4-3.4); 25 were girls (40%) . The median age of RPC marijuana exposures was 2 years (IQR, 1.3-4.0), and 85 patients were girls (52%). The mean rate of marijuana-related visits to the children's hospital increased from 1.2 per 100 000 population 2 years prior to legalization to 2.3 per 100,000 population 2 years after legalization (P = .02). Known marijuana products involved in the exposure included 30 infused edibles (48%). Median length of stay was 11 hours (interquartile range [IQR], 6-19) and 26 hours (IQR, 19-38) for admitted patients. Annual RPC pediatric marijuana cases increased more than 5-fold from 2009 (9) to 2015 (47). Colorado had an

Interrelationships between marijuana demand and discounting of delayed rewards: Convergence in behavioral economic methods.

PubMed

Aston, Elizabeth R; Metrik, Jane; Amlung, Michael; Kahler, Christopher W; MacKillop, James

2016-12-01

Distinct behavioral economic domains, including high perceived drug value (demand) and delay discounting (DD), have been implicated in the initiation of drug use and the progression to dependence. However, it is unclear whether frequent marijuana users conform to a "reinforcer pathology" addiction model wherein marijuana demand and DD jointly increase risk for problematic marijuana use and cannabis dependence (CD). Participants (n=88, 34% female, 14% cannabis dependent) completed a marijuana purchase task at baseline. A delay discounting task was completed following placebo marijuana cigarette (0% THC) administration during a separate experimental session. Marijuana demand and DD were quantified using area under the curve (AUC). In multiple regression models, demand uniquely predicted frequency of marijuana use while DD did not. In contrast, DD uniquely predicted CD symptom count while demand did not. There were no significant interactions between demand and DD in either model. These findings suggest that frequent marijuana users exhibit key constituents of the reinforcer pathology model: high marijuana demand and steep discounting of delayed rewards. However, demand and DD appear to be independent rather than synergistic risk factors for elevated marijuana use and risk for progression to CD. Findings also provide support for using AUC as a singular marijuana demand metric, particularly when also examining other behavioral economic constructs that apply similar statistical approaches, such as DD, to support analytic methodological convergence. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Divergent marijuana trajectories among men: Socioeconomic, relationship, and life satisfaction outcomes in the mid-30s

PubMed Central

White, Helene R.; Bechtold, Jordan; Loeber, Rolf; Pardini, Dustin

2016-01-01

Background Given recent changes in marijuana policy in the United States, it is important to understand the long-term effects of marijuana use on adult functioning. We examined whether men who displayed different trajectories of marijuana use from adolescence through emerging adulthood (age ~15–26) differed in terms of socioeconomic, social, and life satisfaction outcomes in their mid-30s. Methods Data came from a longitudinal sample of men who were recruited in early adolescence (N = 506) and followed into adulthood. Four trajectory groups based on patterns of marijuana use from adolescence into emerging adulthood were compared on adult outcomes (age ~36) before and after controlling for co-occurring use of other substances and several pre-existing confounding factors in early adolescence. The potential moderating effect of race was also examined. Results Although there were initially group differences across all domains, once pre-existing confounds and co-occurring other substance use were included in the model, groups only differed in terms of partner and friend marijuana use. Chronic marijuana users reported the highest proportions of both. Frequent and persistent marijuana use was associated with lower socioeconomic status (SES) for Black men only. Conclusions After statistically accounting for confounding variables, chronic marijuana users were not at a heightened risk for maladjustment in adulthood except for lower SES among Black men. Chronic users were more likely to have friends and partners who also used marijuana. Future studies should take into account pre-existing differences when examining outcomes of marijuana use. PMID:26365837

Prenatal Marijuana Exposure and Intelligence Test Performance at Age 6

ERIC Educational Resources Information Center

Goldschmidt, Lidush; Richardson, Gale A.; Willford, Jennifer; Day, Nancy L.

2008-01-01

A study was conducted on lower income population women who were moderate users of marijuana to examine the effects of prenatal marijuana exposure on children's intellectual development at the age of six. Results concluded that the Cognitive deficits noticed at the age of six were specific to verbal and quantitative reasoning and short-term memory.

An Epidemiological Model for Examining Marijuana Use over the Life Course

PubMed Central

Paddock, Susan M.; Kilmer, Beau; Caulkins, Jonathan P.; Booth, Marika J.; Pacula, Rosalie L.

2012-01-01

Trajectories of drug use are usually studied empirically by following over time persons sampled from either the general population (most often youth and young adults) or from heavy or problematic users (e.g., arrestees or those in treatment). The former, population-based samples, describe early career development, but miss the years of use that generate the greatest social costs. The latter, selected populations, help to summarize the most problematic use, but cannot easily explain how people become problem users nor are they representative of the population as a whole. This paper shows how microsimulation can synthesize both sorts of data within a single analytical framework, while retaining heterogeneous influences that can impact drug use decisions over the life course. The RAND Marijuana Microsimulation Model is constructed for marijuana use, validated, and then used to demonstrate how such models can be used to evaluate alternative policy options aimed at reducing use over the life course. PMID:23236590

Support for marijuana legalization in the US state of Washington has continued to increase through 2016*

PubMed Central

Subbaraman, Meenakshi Sabina; Kerr, William C.

2017-01-01

Background Support for the legalization of recreational marijuana continues to increase across the United States and globally. In 2016, recreational marijuana was legalized in the most populous US state of California, as well as three other states. The primary aim of this study was to examine trends in support for recreational marijuana legalization in Washington, a state which has had legal recreational marijuana for almost four years, using data collected over the four years post-legalization. A secondary aim was to examine trends in support for the cultivation of marijuana for personal use. Methods Data come from geographically representative general population samples of adult (aged 18 and over) Washington residents collected over five timepoints (every six months) between January 2014 and April 2016 (N = 4,101). Random Digit Dial was used for recruitment. Statistical analyses involved bivariate comparisons of proportions across timepoints and subgroups (defined by age, gender, and marijuana user status), and multivariable logistic regression controlling for timepoint (time) to formally test for trend while controlling for demographic and substance use covariates. All analyses adjusted for probability of selection. Results Support for legalization in Washington has significantly increased: support was 64.0% (95% CI: 61.2%–67.8%) at timepoint 1 and 77.9% (95% CI: 73.2%–81.9%) at timepoint 5. With each six months’ passing, support increased 19% on average. We found no statistically significant change in support for home-growing. Conclusions Support for marijuana legalization has continued to significantly increase in a state that has experienced the policy change for almost four years. PMID:28448904

Support for marijuana legalization in the US state of Washington has continued to increase through 2016.

PubMed

Subbaraman, Meenakshi Sabina; Kerr, William C

2017-06-01

Support for the legalization of recreational marijuana continues to increase across the United States and globally. In 2016, recreational marijuana was legalized in the most populous US state of California, as well as three other states. The primary aim of this study was to examine trends in support for recreational marijuana legalization in Washington, a state which has had legal recreational marijuana for almost four years, using data collected over the four years post-legalization. A secondary aim was to examine trends in support for the cultivation of marijuana for personal use. Data come from geographically representative general population samples of adult (aged 18 and over) Washington residents collected over five timepoints (every six months) between January 2014 and April 2016 (N=4101). Random Digit Dial was used for recruitment. Statistical analyses involved bivariate comparisons of proportions across timepoints and subgroups (defined by age, gender, and marijuana user status), and multivariable logistic regression controlling for timepoint (time) to formally test for trend while controlling for demographic and substance use covariates. All analyses adjusted for probability of selection. Support for legalization in Washington has significantly increased: support was 64.0% (95% CI: 61.2%-67.8%) at timepoint 1 and 77.9% (95% CI: 73.2%-81.9%) at timepoint 5. With each six months' passing, support increased 19% on average. We found no statistically significant change in support for home-growing. Support for marijuana legalization has continued to significantly increase in a state that has experienced the policy change for almost four years. Copyright © 2017. Published by Elsevier B.V.

A Collection of NIDA Notes: Articles That Address Research on Marijuana.

ERIC Educational Resources Information Center

National Inst. on Drug Abuse (DHHS/PHS), Bethesda, MD.

Included in this document are selections of topic-specific articles on marijuana research reprinted from the National Institute on Drug Abuse's (NIDA) research newsletter, NIDA Notes. The collection features articles originally published from 1995 through 2002. Topics include long-term cognitive impairments in heavy marijuana users, evidence that…

Periodontal and oral manifestations of marijuana use.

PubMed

Rawal, Swati Y; Tatakis, Dimitris N; Tipton, David A

2012-01-01

Marijuana, prepared from the plant Cannabis sativa, is the most widely used illicit drug in the United States. Marijuana use has been associated with adverse psychosocial and health effects, including effects on oral tissues. Periodontal literature has limited references to the periodontal effects of cannabis use. In this report, we present two cases of marijuana-associated gingival enlargement and review the literature on oral complications of marijuana use. Two asymptomatic males, aged 23 and 42 years, presented independently for oral prophylaxis. Both had an unremarkable medical history and related a history of significant marijuana use of 2-16 years duration. Common findings following oral and periodontal examination were nicotinic stomatitis-like lesions, uvulitis and gingival enlargement. Marginal and papillary gingiva of the anterior dentition were the areas primarily affected by gingival enlargement, while some of these areas exhibited a nodular or "pebbly" appearance. Marijuana-associated gingival enlargement was diagnosed in the reported cases. A review of the literature revealed two other reports of marijuana-associated gingival enlargement, all in young adult males with chronic (2 or more years) cannabis use. These authors reported a resemblance to phenytoin-induced enlargement. Biochemical similarities between phenytoin and cannabis active compounds suggest possible common pathogenetic mechanisms. Uvulitis and nicotinic stomatitis appear to be the two most common of the several oral manifestations of marijuana use. Chronic marijuana use may result in gingival enlargement with clinical characteristics similar to phenytoin-induced enlargement.

National Estimates of Marijuana Use and Related Indicators - National Survey on Drug Use and Health, United States, 2002-2014.

PubMed

Azofeifa, Alejandro; Mattson, Margaret E; Schauer, Gillian; McAfee, Tim; Grant, Althea; Lyerla, Rob

2016-09-02

In the United States, marijuana is the most commonly used illicit drug. In 2013, 7.5% (19.8 million) of the U.S. population aged ≥12 years reported using marijuana during the preceding month. Because of certain state-level policies that have legalized marijuana for medical or recreational use, population-based data on marijuana use and other related indicators are needed to help monitor behavioral health changes in the United States. 2002-2014. The National Survey on Drug Use and Health (NSDUH) is a national- and state-level survey of a representative sample of the civilian, noninstitutionalized U.S. population aged ≥12 years. NSDUH collects information about the use of illicit drugs, alcohol, and tobacco; initiation of substance use; frequency of substance use; substance dependence and abuse; perception of substance harm risk or no risk; and other related behavioral health indicators. This report describes national trends for selected marijuana use and related indicators, including prevalence of marijuana use; initiation; perception of harm risk, approval, and attitudes; perception of availability and mode of acquisition; dependence and abuse; and perception of legal penalty for marijuana possession. In 2014, a total of 2.5 million persons aged ≥12 years had used marijuana for the first time during the preceding 12 months, an average of approximately 7,000 new users each day. During 2002-2014, the prevalence of marijuana use during the past month, past year, and daily or almost daily increased among persons aged ≥18 years, but not among those aged 12-17 years. Among persons aged ≥12 years, the prevalence of perceived great risk from smoking marijuana once or twice a week and once a month decreased and the prevalence of perceived no risk increased. The prevalence of past year marijuana dependence and abuse decreased, except among persons aged ≥26 years. Among persons aged ≥12 years, the percentage reporting that marijuana was fairly easy or very easy

Marijuana use and mortality.

PubMed Central

Sidney, S; Beck, J E; Tekawa, I S; Quesenberry, C P; Friedman, G D

1997-01-01

OBJECTIVES: The purpose of this study was to examine the relationship of marijuana use to mortality. METHODS: The study population comprised 65171 Kaiser Permanente Medical Care Program enrollees, aged 15 through 49 years, who completed questionnaires about smoking habits, including marijuana use, between 1979 and 1985. Mortality follow-up was conducted through 1991. RESULTS: Compared with nonuse or experimentation (lifetime use six or fewer times), current marijuana use was not associated with a significantly increased risk of non-acquired immunodeficiency syndrome (AIDS) mortality in men (relative risk [RR] = 1.12, 95% confidence interval [CI] = 0.89, 1.39) or of total mortality in women (RR = 1.09, 95% CI = 0.80, 1.48). Current marijuana use was associated with increased risk of AIDS mortality in men (RR = 1.90, 95% CI = 1.33, 2.73), an association that probably was not causal but most likely represented uncontrolled confounding by male homosexual behavior. This interpretation was supported by the lack of association of marijuana use with AIDS mortality in men from a Kaiser Permanente AIDS database. Relative risks for ever use of marijuana were similar. CONCLUSIONS: Marijuana use in a prepaid health care-based study cohort had little effect on non-AIDS mortality in men and on total mortality in women. PMID:9146436

Marijuana motivations across adolescence: impacts on use and consequences.

PubMed

Anderson, Kristen G; Sitney, Miranda; White, Helene R

2015-02-01

Background. Motivational models for marijuana use have focused on reasons to use marijuana, but rarely consider motives to abstain. We examined how both adolescent marijuana abstinence motives and use motives contribute to marijuana use and problems at the end of emerging adulthood. Methods. 434 community recruited youth who had not initiated marijuana use at baseline were followed from adolescence (at ages 12, 15, and 18 years) into emerging adulthood (age 25 years). Motives to abstain and to use marijuana, marijuana consumption, and marijuana-related problems were assessed across time. Results. Endorsing more motives to abstain from marijuana across adolescence predicted less marijuana use in emerging adulthood and fewer marijuana-related problems when controlling for past motives to abstain and marijuana-related behavior. Positive reinforcement use motives related to increased marijuana consumption and problems, and negative reinforcement motives predicted problems when controlling for past marijuana use motives and behaviors. Expansion motives during adolescence related to lower marijuana use in emerging adulthood. When considered together, motives to abstain buffered the effect of negative reinforcement motives on outcomes at age 25 for youth endorsing a greater number of abstinence motives. Conclusions/ Implications. Given these findings, inclusion of both motives to use and abstain is warranted within comprehensive models of marijuana use decision making and may provide important markers for prevention and intervention specialists.

Marijuana-using drivers, alcohol-using drivers, and their passengers: prevalence and risk factors among underage college students.

PubMed

Whitehill, Jennifer M; Rivara, Frederick P; Moreno, Megan A

2014-07-01

Driving after marijuana use increases the risk of a motor vehicle crash. Understanding this behavior among young drivers and how it may differ from alcohol-related driving behaviors could inform prevention efforts. To describe the prevalence, sex differences, and risk factors associated with underage college students' driving after using marijuana, driving after drinking alcohol, or riding with a driver using these substances. Cross-sectional telephone survey of a random sample of 315 first-year college students (aged 18-20 years) from 2 large public universities, who were participating in an ongoing longitudinal study. At recruitment, 52.8% of eligible individuals consented to participate; retention was 93.2% one year later when data for this report were collected. Self-reported past-28-day driving after marijuana use, riding with a marijuana-using driver, driving after alcohol use, and riding with an alcohol-using driver. In the prior month, 20.3% of students had used marijuana. Among marijuana-using students, 43.9% of male and 8.7% of female students drove after using marijuana (P < .001), and 51.2% of male and 34.8% of female students rode as a passenger with a marijuana-using driver (P = .21). Most students (65.1%) drank alcohol, and among this group 12.0% of male students and 2.7% of female students drove after drinking (P = .01), with 20.7% and 11.5% (P = .07), respectively, reporting riding with an alcohol-using driver. Controlling for demographics and substance use behaviors, driving after substance use was associated with at least a 2-fold increase in risk of being a passenger with another user; the reverse was also true. A 1% increase in the reported percentage of friends using marijuana was associated with a 2% increased risk of riding with a marijuana-using driver (95% CI, 1.01-1.03). Among students using any substances, past-28-day use of only marijuana was associated with a 6.24-fold increased risk of driving after substance use

Marijuana

MedlinePlus

Marijuana is a green, brown, or gray mix of dried, crumbled parts from the marijuana plant. It can be rolled up and smoked ... in food or inhale it using a vaporizer. Marijuana can cause problems with memory, learning, and behavior. ...

The association between regular marijuana use and adult mental health outcomes.

PubMed

Guttmannova, Katarina; Kosterman, Rick; White, Helene R; Bailey, Jennifer A; Lee, Jungeun Olivia; Epstein, Marina; Jones, Tiffany M; Hawkins, J David

2017-10-01

The present study is a prospective examination of the relationship between regular marijuana use from adolescence through young adulthood and mental health outcomes at age 33. Data came from a gender-balanced, ethnically diverse longitudinal panel of 808 participants from Seattle, Washington. Outcomes included symptom counts for six mental health disorders. Regular marijuana use was tracked during adolescence and young adulthood. Regression analyses controlled for demographics and early environment, behaviors, and individual risk factors. Nonusers of marijuana reported fewer symptoms of alcohol use disorder, nicotine dependence, and generalized anxiety disorder than any category of marijuana users. More persistent regular marijuana use in young adulthood was positively related to more symptoms of cannabis use disorder, alcohol use disorder, and nicotine dependence at age 33. Findings highlight the importance of avoiding regular marijuana use, especially chronic use in young adulthood. Comprehensive prevention and intervention efforts focusing on marijuana and other substance use might be particularly important in the context of recent legalization of recreational marijuana use in Washington and other U.S. states. Copyright © 2017 Elsevier B.V. All rights reserved.

Medical marijuana

MedlinePlus

... this page: //medlineplus.gov/ency/patientinstructions/000899.htm Medical marijuana To use the sharing features on this page, ... have legalized marijuana for medical use. How Does Medical Marijuana Work? Medical marijuana may be: Smoked Vaporized Eaten ...

Does social context matter? An ecological momentary assessment study of marijuana use among college students.

PubMed

Phillips, Kristina T; Phillips, Michael M; Lalonde, Trent L; Prince, Mark A

2018-08-01

Past research has shown that marijuana use occurs commonly in social situations for young adults, though few studies have examined the association between immediate social context and marijuana use patterns and associated problems. The current study examined the impact of demographics, marijuana use and problem use, alcohol use, craving, and social context on the likelihood of using marijuana with others via ecological momentary assessment (EMA). College-student marijuana users (N=56) were recruited and completed a baseline assessment and training on the two-week signal-contingent EMA protocol. Participants were sent text messages three times per day randomly for two weeks. Of the 1131 EMA instances during which participants reported using marijuana, 862 (76.22%) were labeled as being with others. Forty-five participants (80.36%) reported marijuana use with others present during at least half of the times they used marijuana. Findings from a multilevel logistic regression model showed a significant positive association between the probability of using with others and minutes spent using marijuana (b=0.047, p<0.001), social facilitation (b=0.138, p<0.001), and DSM-IV diagnosis (dependence versus no diagnosis, b=1.350, p=0.047). Cannabis dependence, more time using marijuana in the moment, and using for social facilitation purposes were positively associated with using marijuana in the context of being with others. Daily users had more variability in terms of the social context of their use. This study illustrates the complex relationship between social context and marijuana use. Copyright © 2018 Elsevier Ltd. All rights reserved.

Bayesian inference for the distribution of grams of marijuana in a joint.

PubMed

Ridgeway, Greg; Kilmer, Beau

2016-08-01

The average amount of marijuana in a joint is unknown, yet this figure is a critical quantity for creating credible measures of marijuana consumption. It is essential for projecting tax revenues post-legalization, estimating the size of illicit marijuana markets, and learning about how much marijuana users are consuming in order to understand health and behavioral consequences. Arrestee Drug Abuse Monitoring data collected between 2000 and 2010 contain relevant information on 10,628 marijuana transactions, joints and loose marijuana purchases, including the city in which the purchase occurred and the price paid for the marijuana. Using the Brown-Silverman drug pricing model to link marijuana price and weight, we are able to infer the distribution of grams of marijuana in a joint and provide a Bayesian posterior distribution for the mean weight of marijuana in a joint. We estimate that the mean weight of marijuana in a joint is 0.32g (95% Bayesian posterior interval: 0.30-0.35). Our estimate of the mean weight of marijuana in a joint is lower than figures commonly used to make estimates of marijuana consumption. These estimates can be incorporated into drug policy discussions to produce better understanding about illicit marijuana markets, the size of potential legalized marijuana markets, and health and behavior outcomes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Medical Marijuana Legalization and Marijuana Use Among Youth in Oregon.

PubMed

Paschall, Mallie J; Grube, Joel W; Biglan, Anthony

2017-06-01

While the legalization of marijuana for medical and recreational use has raised concerns about potential influences on marijuana use and beliefs among youth, few empirical studies have addressed this issue. We examined the association between medical marijuana patients and licensed growers per 1000 population in 32 Oregon counties from 2006 to 2015, and marijuana use among youth over the same period. We obtained data on registered medical marijuana patients and licensed growers from the Oregon Medical Marijuana Program and we obtained data on youth marijuana use, perceived parental disapproval, and demographic characteristics from the Oregon Healthy Teens Survey. Across 32 Oregon counties, the mean rate of marijuana patients per 1000 population increased from 2.9 in 2006 to 18.3 in 2015, whereas the grower rate increased from 3.8 to 11.9. Results of multi-level analyses indicated significant positive associations between rates of marijuana patients and growers per 1000 population and the prevalence of past 30-day marijuana use, controlling for youth demographic characteristics. The marijuana patient and grower rates were also inversely associated with parental disapproval of marijuana use, which decreased from 2006 to 2015 and acted as a mediator. These findings suggest that a greater number of registered marijuana patients and growers per 1000 population in Oregon counties was associated with a higher prevalence of marijuana use among youth from 2006 to 2015, and that this relationship was partially attributable to perceived norms favorable towards marijuana use.

Measuring Protective Behavioral Strategies for Marijuana Use Among Young Adults.

PubMed

Pedersen, Eric R; Hummer, Justin F; Rinker, Dipali Venkataraman; Traylor, Zach K; Neighbors, Clayton

2016-05-01

Marijuana use can result in a variety of negative consequences, yet it remains popular among young adults and the general public at large. Combined with the growing empirical support for the benefits of medicinal marijuana as well as the steady increase in popular opinion regarding its legalization, it is of growing importance to identify strategies that may mitigate the harms related to marijuana use, reduce consumption levels, and limit resulting negative consequences among young adults who use marijuana. The purpose of this study was to develop and conduct initial psychometric analyses on a new scale, which we named the Protective Behavioral Strategies for Marijuana (PBSM) scale. A sample of undergraduate college students who reported past-6-month marijuana use (n = 210) responded to the initial pool of PBSM items and completed measures of marijuana use, consequences from marijuana use, alcohol use, and protective behavioral strategies for alcohol. Results from an iterative principal component analyses process yielded a single-factor structure with 39 items. The PBSM mean composite score negatively associated with marijuana use and consequences, with the strongest correlations evident for pastmonth users. The PBSM also significantly positively correlated with alcohol protective strategies. Protective behavioral strategies for marijuana appear to be a measurable construct that are related to marijuana frequency and consequences, and thus may be a useful component of intervention and prevention programs with young adults. More work testing the PBSM items with larger and more diverse samples of young adults is encouraged.

Young adults report increased pleasure from smoking cigarettes when drinking alcohol but not when using marijuana.

PubMed

Gubner, Noah R; Thrul, Johannes; Kelly, Oona A; Ramo, Danielle E

2018-01-01

Among young adults, cigarette smoking is strongly associated with alcohol and marijuana use. The present study compared self-reported co-use of cigarettes and alcohol versus cigarettes and marijuana among young adults using cross-sectional survey data. Participants were young adult cigarette smokers (age 18 to 25) who also reported past month alcohol or marijuana use enrolled in a randomized trial testing a smoking cessation intervention on Facebook. Participants self-reported extent of cigarette smoking under the influence of alcohol or marijuana and differences in perceived pleasure from cigarette smoking when drinking alcohol compared to using marijuana. Among cigarette smokers who drank alcohol and used marijuana in the past month (n=200), a similar percentage of cigarettes were smoked under the influence of alcohol (42.4%±31.2%) and marijuana (43.1% ±30.0%). Among alcohol + marijuana users, perceived pleasure from smoking cigarettes was significantly greater when drinking alcohol versus when using marijuana (t (199) =7.05, p<0.001). There was, on average, an increase in perceived pleasure from smoking cigarettes when drinking alcohol, though perceived pleasure did not differ by binge drinking frequency. In contrast, there was on average no change in perceived pleasure from smoking cigarettes when using marijuana. Results from the cigarette smokers who used alcohol + marijuana were similar to cigarette smokers who only used alcohol (n=158) or only used marijuana (n=54). Findings highlight greater perceived reward from smoking cigarettes when drinking alcohol compared to when using marijuana, informing smoking cessation interventions that target users of multiple substances.

Attitudes, perceptions, and use of marijuana in youth with multiple sclerosis.

PubMed

Brenton, J Nicholas; Schreiner, Teri; Karoscik, Krystle; Richter, Meg; Ferrante, Samantha; Waldman, Amy; Banwell, Brenda

2018-02-01

Studies have shown a negative impact on cognition and brain volume in marijuana-using adult multiple sclerosis (MS) patients and healthy adolescents. Given that onset of MS during childhood and adolescence negatively impacts brain growth and the normal maturation of neuronal networks, the addition of marijuana exposure in these youth may be even more harmful. Determine attitudes toward and prevalence of recreational marijuana use in MS youth. We surveyed 52 consecutive pediatric-onset MS patients from three pediatric MS centers in the United States. Participants answered a structured questionnaire to capture attitudes toward marijuana and personal use habits, if present. Nearly half reported use of marijuana, with the majority beginning to use in mid-to-late adolescence. The most popular reasons for using marijuana were relaxation (72%), improvement of medical problems (64%), and stress reduction (52%). Over half (64%) of marijuana users perceived it to have negative effects on memory and focus. Cost and access were not barriers to use, despite all respondents being less than age 21. Youth with MS endorse recreational marijuana as safe, and many use marijuana frequently despite appreciating a negative impact on memory. More detailed understanding of the long-term impact of marijuana use in youth with MS is needed.

Multiple Cerebral Infarcts in a Young Patient Associated With Marijuana Use.

PubMed

Volpon, Leila Costa; Sousa, Camila Lacerda Muniz de Melo; Moreira, Silvia Keiko Kavaguti; Teixeira, Sara Reis; Carlotti, Ana Paula de Carvalho Panzeri

: Cerebrovascular events associated with marijuana use have been reported previously. This association is plausible, but not well-established yet. A 14-year-old girl, long-term heavy cannabis user, presented with generalized tonic-clonic seizures and decreased level of consciousness a few hours after smoking cannabis. Brain magnetic resonance imaging showed multiple areas of acute, subacute and chronic ischemic lesions in the left frontal lobe, basal ganglia, and corpus callosum. History of other illicit drug use and other known causes of stroke were ruled out. Cannabis might cause stroke through direct effects on the cerebral blood circulation, orthostatic hypotension, vasculitis, vasospasm, and atrial fibrillation. Long-term daily use of marijuana in young people may cause serious damage to the cerebrovascular system.

The availability of medical marijuana dispensary and adolescent marijuana use.

PubMed

Shi, Yuyan

2016-10-01

To examine the association between medical marijuana dispensary (MMD) availability and adolescent marijuana use. The study sample was comprised of 8th, 10th, and 12th graders (N=14,953) from 141 schools in the 2014 Monitoring the Future study, who resided in the 18 states that had legalized medical marijuana as of January 1, 2014. Multilevel logistic regressions with random effects were conducted to quantify the cross-sectional associations of the availability of MMD within 5- and 25-mile buffers from the centroid of school zip codes with self-reported recent use (past-year) and current use (past-month) of marijuana, controlling for individual characteristics and school, zip code, and state contextual factors. In the combined sample, the availability of MMD was not associated with recent or current use of marijuana. Subsample analyses suggested that the availability within a 5-mile buffer was associated with a higher likelihood of recent use in 8th graders (OR=1.93, 95% CI=1.11-3.33) and the availability within a 5- to 25-mile buffer was associated with a higher likelihood of recent use in 10th graders (OR=1.33, 95% CI=1.00-1.77). The availability of MMD was not associated with recent use in 12th graders or current use in any grades. The availability of MMD was not associated with current use of marijuana among adolescents. There was some evidence suggesting that the availability of MMD within short to medium traveling distance may be associated with a higher level of recent use in middle schoolers who are also at a high risk of experimenting with marijuana. Copyright © 2016 Elsevier Inc. All rights reserved.

Recreational Marijuana Use and Acute Myocardial Infarction: Insights from Nationwide Inpatient Sample in the United States.

PubMed

Desai, Rupak; Patel, Upenkumar; Sharma, Shobhit; Amin, Parth; Bhuva, Rushikkumar; Patel, Malav S; Sharma, Nitin; Shah, Manan; Patel, Smit; Savani, Sejal; Batra, Neha; Kumar, Gautam

2017-11-03

Background Marijuana is a widely used recreational substance. Few cases have been reported of acute myocardial infarction following marijuana use. To our knowledge, this is the first ever study analyzing the lifetime odds of acute myocardial infarction (AMI) with marijuana use and the outcomes in AMI patients with versus without marijuana use. Methods We queried the 2010-2014 National Inpatient Sample (NIS) database for 11-70-year-old AMI patients. Pearson Chi-square test for categorical variables and Student T-test for continuous variables were used to compare the baseline demographic and hospital characteristics between two groups (without vs. with marijuana) of AMI patients. The univariate and multivariate analyses were used to assess and compare the clinical outcomes between two groups. We used Cochran-Armitage test to measure the trends. All statistical analyses were executed by IBM SPSS Statistics 22.0 (IBM Corp., Armonk, NY). We used weighted data to produce national estimates in our study. Results Out of 2,451,933 weighted hospitalized AMI patients, 35,771 patients with a history of marijuana and 2,416,162 patients without a history of marijuana use were identified. The AMI-marijuana group consisted more of younger, male, African American patients. The length of stay and mortality rate were lower in the AMI-marijuana group with more patients being discharged against medical advice. Multivariable analysis showed that marijuana use was a significant risk factor for AMI development when adjusted for age, sex, race (adjusted OR 1.079, 95% CI 1.065-1.093, p<0.001); adjusted for age, female, race, smoking, cocaine abuse (adjusted OR 1.041, 95% CI 1.027-1.054, p<0.001); and also when adjusted for age, female, race, payer status, smoking, cocaine abuse, amphetamine abuse and alcohol abuse (adjusted OR: 1.031, 95% CI: 1.018-1.045, p<0.001). Complications such as respiratory failure (OR 18.9, CI 15.6-23.0, p<0.001), cerebrovascular disease (OR 9.0, CI 7.0-11.7, p<0

Latent factor structure of a behavioral economic marijuana demand curve.

PubMed

Aston, Elizabeth R; Farris, Samantha G; MacKillop, James; Metrik, Jane

2017-08-01

Drug demand, or relative value, can be assessed via analysis of behavioral economic purchase task performance. Five demand indices are typically obtained from drug purchase tasks. The goal of this research was to determine whether metrics of marijuana reinforcement from a marijuana purchase task (MPT) exhibit a latent factor structure that efficiently characterizes marijuana demand. Participants were regular marijuana users (n = 99; 37.4% female, 71.5% marijuana use days [5 days/week], 15.2% cannabis dependent) who completed study assessments, including the MPT, during a baseline session. Principal component analysis was used to examine the latent structure underlying MPT indices. Concurrent validity was assessed via examination of relationships between latent factors and marijuana use, past quit attempts, and marijuana expectancies. A two-factor solution was confirmed as the best fitting structure, accounting for 88.5% of the overall variance. Factor 1 (65.8% variance) reflected "Persistence," indicating sensitivity to escalating marijuana price, which comprised four MPT indices (elasticity, O max , P max , and breakpoint). Factor 2 (22.7% variance) reflected "Amplitude," indicating the amount consumed at unrestricted price (intensity). Persistence factor scores were associated with fewer past marijuana quit attempts and lower expectancies of negative use outcomes. Amplitude factor scores were associated with more frequent use, dependence symptoms, craving severity, and positive marijuana outcome expectancies. Consistent with research on alcohol and cigarette purchase tasks, the MPT can be characterized with a latent two-factor structure. Thus, demand for marijuana appears to encompass distinct dimensions of price sensitivity and volumetric consumption, with differential relations to other aspects of marijuana motivation.

An Item Response Theory Modeling of Alcohol and Marijuana Dependences: A National Drug Abuse Treatment Clinical Trials Network Study*

PubMed Central

Wu, Li-Tzy; Pan, Jeng-Jong; Blazer, Dan G.; Tai, Betty; Stitzer, Maxine L.; Brooner, Robert K.; Woody, George E.; Patkar, Ashwin A.; Blaine, Jack D.

2009-01-01

Objective: The aim of this study was to examine psychometric properties of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), diagnostics criteria for alcohol and marijuana dependences among 462 alcohol users and 311 marijuana users enrolled in two multisite trials of the National Drug Abuse Treatment Clinical Trials Network. Method: Diagnostic questions were assessed by the DSM-IV checklist. Data were analyzed by the item response theory and the multiple indicators–multiple causes method procedures. Results: Criterion symptoms of alcohol and marijuana dependences exhibited a high level of internal consistency. All individual symptoms showed good discrimination in distinguishing alcohol or marijuana users between high and low severity levels of the continuum. In both groups, “withdrawal” appeared to measure the most severe symptom of the dependence continuum. There was little evidence of measurement nonequivalence in assessing symptoms of dependence by gender, age, race/ethnicity, and educational level. Conclusions: These findings highlight the clinical utility of the DSM-IV checklist in assessing alcohol- and marijuana-dependence syndromes among treatment-seeking substance users. PMID:19371493

Marijuana Use and Estimated Glomerular Filtration Rate in Young Adults.

PubMed

Ishida, Julie H; Auer, Reto; Vittinghoff, Eric; Pletcher, Mark J; Reis, Jared P; Sidney, Stephen; Johansen, Kirsten L; Bibbins-Domingo, Kirsten; Peralta, Carmen A; Shlipak, Michael G

2017-10-06

Marijuana use has become more widely accepted in the United States and has been legalized in many areas. Although it is biologically plausible that marijuana could affect kidney function, epidemiologic data are lacking. We conducted a cohort study among young adults with preserved eGFR ( i.e. , eGFR≥60 ml/min per 1.73 m 2 ) using data from the Coronary Artery Risk Development in Young Adults (CARDIA) study. At scheduled examinations occurring every 5 years and starting at study year 10 (calendar years, 1995-1996), cystatin C was collected over a 10-year period, and urine albumin-to-creatinine ratio was collected over a 15-year period. We investigated the cross-sectional association between current and cumulative marijuana use (in marijuana-years; one marijuana-year equals 365 days of marijuana use) and eGFR by cystatin C (eGFR cys ) at year 10. In longitudinal analyses, we investigated the association between cumulative marijuana use and eGFR cys change and rapid (≥3%/year) eGFR cys decline over two 5-year intervals and prevalent albuminuria (urine albumin-to-creatinine ratio ≥30 mg/g) over a 15-year period. Past or current marijuana use was reported by 83% (3131 of 3765) of the cohort, and the mean eGFR cys was 111 ml/min per 1.73 m 2 at year 10. Over the following 10 years, 504 had rapid eGFR cys decline, and over the following 15 years, 426 had prevalent albuminuria. Compared with no use, daily current use and ≥5 marijuana-years of cumulative use were associated with lower eGFR cys at year 10: -4.5% (95% confidence interval, -8.1 to -0.7%; P =0.02) and -3.0% (95% confidence interval, -5.6 to -0.4%; P =0.03), respectively. Marijuana use was not significantly associated with eGFR cys change, rapid eGFR cys decline, or prevalent albuminuria. Although we identified a modest cross-sectional association between higher marijuana exposure and lower eGFR cys among young adults with preserved eGFR, our findings were largely null and did not demonstrate a

Marijuana smoking and the risk of head and neck cancer: pooled analysis in the INHANCE consortium.

PubMed

Berthiller, Julien; Lee, Yuan-Chin Amy; Boffetta, Paolo; Wei, Qingyi; Sturgis, Erich M; Greenland, Sander; Morgenstern, Hal; Zhang, Zuo-Feng; Lazarus, Philip; Muscat, Joshua; Chen, Chu; Schwartz, Stephen M; Eluf Neto, José; Wünsch Filho, Victor; Koifman, Sergio; Curado, Maria Paula; Matos, Elena; Fernandez, Leticia; Menezes, Ana; Daudt, Alexander W; Ferro, Gilles; Brennan, Paul; Hashibe, Mia

2009-05-01

Marijuana contains carcinogens similar to tobacco smoke and has been suggested by relatively small studies to increase the risk of head and neck cancer (HNC). Because tobacco is a major risk factor for HNC, large studies with substantial numbers of never tobacco users could help to clarify whether marijuana smoking is independently associated with HNC risk. We pooled self-reported interview data on marijuana smoking and known HNC risk factors on 4,029 HNC cases and 5,015 controls from five case-control studies within the INHANCE Consortium. Subanalyses were conducted among never tobacco users (493 cases and 1,813 controls) and among individuals who did not consume alcohol or smoke tobacco (237 cases and 887 controls). The risk of HNC was not elevated by ever marijuana smoking [odds ratio (OR), 0.88; 95% confidence intervals (95% CI), 0.67-1.16], and there was no increasing risk associated with increasing frequency, duration, or cumulative consumption of marijuana smoking. An increased risk of HNC associated with marijuana use was not detected among never tobacco users (OR, 0.93; 95% CI, 0.63-1.37; three studies) nor among individuals who did not drink alcohol and smoke tobacco (OR, 1.06; 95% CI, 0.47-2.38; two studies). Our results are consistent with the notion that infrequent marijuana smoking does not confer a risk of these malignancies. Nonetheless, because the prevalence of frequent marijuana smoking was low in most of the contributing studies, we could not rule out a moderately increased risk, particularly among subgroups without exposure to tobacco and alcohol.

Medical Marijuana.

PubMed

Capriotti, Teri

2016-01-01

The use of medicinal marijuana is increasing. Marijuana has been shown to have therapeutic effects in certain patients, but further research is needed regarding the safety and efficacy of marijuana as a medical treatment for various conditions. A growing body of research validates the use of marijuana for a variety of healthcare problems, but there are many issues surrounding the use of this substance. This article discusses the use of medical marijuana and provides implications for home care clinicians.

Effects of Marijuana Use on Impulsivity and Hostility in Daily Life

PubMed Central

Ansell, Emily B.; Laws, Holly B.; Roche, Michael J.; Sinha, Rajita

2015-01-01

BACKGROUND Marijuana use is increasingly prevalent among young adults. While research has found adverse effects associated with marijuana use within experimentally controlled laboratory settings, it is unclear how recreational marijuana use affects day-to-day experiences in users. The present study sought to examine the effects of marijuana use on within-person changes in impulsivity and interpersonal hostility in daily life using smartphone administered assessments. METHODS Forty-three participants with no substance dependence reported on their alcohol consumption, tobacco use, recreational marijuana use, impulsivity, and interpersonal hostility over the course of 14 days. Responses were analyzed using multilevel modeling. RESULTS Marijuana use was associated with increased impulsivity on the same day and the following day relative to days when marijuana was not used, independent of alcohol use. Marijuana was also associated with increased hostile behaviors and perceptions of hostility in others on the same day when compared to days when marijuana was not used. These effects were independent of frequency of marijuana use or alcohol use. There were no significant effects of alcohol consumption on impulsivity or interpersonal hostility. CONCLUSIONS Marijuana use is associated with changes in impulse control and hostility in daily life. This may be one route by which deleterious effects of marijuana are observed for mental health and psychosocial functioning. Given the increasing prevalence of recreational marijuana use and the potential legalization in some states, further research on the potential consequences of marijuana use in young adults’ day-to-day life is warranted. PMID:25595054

Measuring Protective Behavioral Strategies for Marijuana Use Among Young Adults

PubMed Central

Pedersen, Eric R.; Hummer, Justin F.; Rinker, Dipali Venkataraman; Traylor, Zach K.; Neighbors, Clayton

2016-01-01

Objective: Marijuana use can result in a variety of negative consequences, yet it remains popular among young adults and the general public at large. Combined with the growing empirical support for the benefits of medicinal marijuana as well as the steady increase in popular opinion regarding its legalization, it is of growing importance to identify strategies that may mitigate the harms related to marijuana use, reduce consumption levels, and limit resulting negative consequences among young adults who use marijuana. The purpose of this study was to develop and conduct initial psychometric analyses on a new scale, which we named the Protective Behavioral Strategies for Marijuana (PBSM) scale. Method: A sample of undergraduate college students who reported past-6-month marijuana use (n = 210) responded to the initial pool of PBSM items and completed measures of marijuana use, consequences from marijuana use, alcohol use, and protective behavioral strategies for alcohol. Results: Results from an iterative principal component analyses process yielded a single-factor structure with 39 items. The PBSM mean composite score negatively associated with marijuana use and consequences, with the strongest correlations evident for past-month users. The PBSM also significantly positively correlated with alcohol protective strategies. Conclusions: Protective behavioral strategies for marijuana appear to be a measurable construct that are related to marijuana frequency and consequences, and thus may be a useful component of intervention and prevention programs with young adults. More work testing the PBSM items with larger and more diverse samples of young adults is encouraged. PMID:27172576

Characterizing the Followers and Tweets of a Marijuana-Focused Twitter Handle

PubMed Central

Krauss, Melissa; Grucza, Richard; Bierut, Laura

2014-01-01

Background Twitter is a popular social media forum for sharing personal experiences, interests, and opinions. An improved understanding of the discourse on Twitter that encourages marijuana use can be helpful for tailoring and targeting online and offline prevention messages. Objectives The intent of the study was to assess the content of “tweets” and the demographics of followers of a popular pro-marijuana Twitter handle (@stillblazingtho). Methods We assessed the sentiment and content of tweets (sent from May 1 to December 31, 2013), as well as the demographics of consumers that follow a popular pro-marijuana Twitter handle (approximately 1,000,000 followers) using Twitter analytics from Demographics Pro. This analytics company estimates demographic characteristics based on Twitter behavior/usage, relying on multiple data signals from networks, consumption, and language and requires confidence of 95% or above to make an estimate of a single demographic characteristic. Results A total of 2590 tweets were sent from @stillblazingtho during the 8-month period and 305 (11.78%) replies to another Twitter user were excluded for qualitative analysis. Of the remaining 2285 tweets, 1875 (82.06%) were positive about marijuana, 403 (17.64%) were neutral, and 7 (0.31%) appeared negative about marijuana. Approximately 1101 (58.72%) of the positive marijuana tweets were perceived as jokes or humorous, 340 (18.13%) implied that marijuana helps you to feel good or relax, 294 (15.68%) mentioned routine, frequent, or heavy use, 193 (10.29%) mentioned blunts, marijuana edibles, or paraphernalia (eg, bongs, vaporizers), and 186 (9.92%) mentioned other risky health behaviors (eg, tobacco, alcohol, other drugs, sex). The majority (699,103/959,143; 72.89%) of @stillblazingtho followers were 19 years old or younger. Among people ages 17 to 19 years, @stillblazingtho was in the top 10% of all Twitter handles followed. More followers of @stillblazingtho in the United States were

Characterizing the followers and tweets of a marijuana-focused Twitter handle.

PubMed

Cavazos-Rehg, Patricia; Krauss, Melissa; Grucza, Richard; Bierut, Laura

2014-06-27

Twitter is a popular social media forum for sharing personal experiences, interests, and opinions. An improved understanding of the discourse on Twitter that encourages marijuana use can be helpful for tailoring and targeting online and offline prevention messages. The intent of the study was to assess the content of "tweets" and the demographics of followers of a popular pro-marijuana Twitter handle (@stillblazingtho). We assessed the sentiment and content of tweets (sent from May 1 to December 31, 2013), as well as the demographics of consumers that follow a popular pro-marijuana Twitter handle (approximately 1,000,000 followers) using Twitter analytics from Demographics Pro. This analytics company estimates demographic characteristics based on Twitter behavior/usage, relying on multiple data signals from networks, consumption, and language and requires confidence of 95% or above to make an estimate of a single demographic characteristic. A total of 2590 tweets were sent from @stillblazingtho during the 8-month period and 305 (11.78%) replies to another Twitter user were excluded for qualitative analysis. Of the remaining 2285 tweets, 1875 (82.06%) were positive about marijuana, 403 (17.64%) were neutral, and 7 (0.31%) appeared negative about marijuana. Approximately 1101 (58.72%) of the positive marijuana tweets were perceived as jokes or humorous, 340 (18.13%) implied that marijuana helps you to feel good or relax, 294 (15.68%) mentioned routine, frequent, or heavy use, 193 (10.29%) mentioned blunts, marijuana edibles, or paraphernalia (eg, bongs, vaporizers), and 186 (9.92%) mentioned other risky health behaviors (eg, tobacco, alcohol, other drugs, sex). The majority (699,103/959,143; 72.89%) of @stillblazingtho followers were 19 years old or younger. Among people ages 17 to 19 years, @stillblazingtho was in the top 10% of all Twitter handles followed. More followers of @stillblazingtho in the United States were African American (323,107/759,407; 42.55%) or

Marijuana intoxication

MedlinePlus

Cannabis intoxication; Intoxication - marijuana (cannabis); Pot; Mary Jane; Weed; Grass; Cannabis ... The intoxicating effects of marijuana include relaxation, ... to fast and predictable signs and symptoms. Eating marijuana ...

Marijuana-Using Drivers, Alcohol-Using drivers and Their Passengers: Prevalence and Risk Factors Among Underage College Students

PubMed Central

Whitehill, Jennifer M.; Rivara, Frederick P.; Moreno, Megan A.

2014-01-01

Importance Driving after marijuana use increases the risk of a motor vehicle crash. Understanding this behavior among young drivers and how it may differ from alcohol-related driving behaviors could inform prevention efforts. Objective To describe prevalence, sex differences, and risk factors associated with underage college students’ driving after using marijuana, driving after drinking alcohol, or riding with a driver using these substances. Design, Setting, Participants Cross-sectional telephone survey of a random sample of 315 first-year college students (aged 18-20 years) from 2 large public universities, who were participating in an ongoing longitudinal study. At recruitment, 52.8% of eligible individuals consented to participate; retention was 93.2% one year later when data for this report was collected. Main Outcome Measure(s) Self-reported past-28-day driving after marijuana use, riding with a marijuana-using driver, driving after alcohol use, and riding with an alcohol-using driver. Results In the prior month, 20.3% of students had used marijuana. Among marijuana-using students, 43.9% of males and 8.7% of females drove after using marijuana (p<0.001) and 51.2% of male and 34.8% of female students rode as a passenger with a marijuana-using driver (p=0.21). Most students (65.1%) drank alcohol, and among this group 12.0% of male students and 2.7% of female students drove after drinking (p=0.01), with 20.7% and 11.5% (p=0.07), respectively, reporting riding with a drinking driver. Controlling for demographics and substance use behaviors, driving after substance use was associated with at least a 2-fold increase in risk of being a passenger with another user; the reverse was also true. A 1% increase in the reported percentage of friends using marijuana was associated with a 2% increased risk of riding with a marijuana using driver (95% CI=1.01-1.03). Among students using any substances, past 28-day use of only marijuana was associated with a 6.24-fold

Loose regulation of medical marijuana programs associated with higher rates of adult marijuana use but not cannabis use disorder.

PubMed

Williams, Arthur Robin; Santaella-Tenorio, Julian; Mauro, Christine M; Levin, Frances R; Martins, Silvia S

2017-11-01

Most US states have passed medical marijuana laws (MMLs), with great variation in program regulation impacting enrollment rates. We aimed to compare changes in rates of marijuana use, heavy use and cannabis use disorder across age groups while accounting for whether states enacted medicalized (highly regulated) or non-medical mml programs. Difference-in-differences estimates with time-varying state-level MML coded by program type (medicalized versus non-medical). Multi-level linear regression models adjusted for state-level random effects and covariates as well as historical trends in use. Nation-wide cross-sectional survey data from the US National Survey of Drug Use and Health (NSDUH) restricted use data portal aggregated at the state level. Participants comprised 2004-13 NSDUH respondents (n ~ 67 500/year); age groups 12-17, 18-25 and 26+ years. States had implemented eight medicalized and 15 non-medical MML programs. Primary outcome measures included (1) active (past-month) marijuana use; (2) heavy use (> 300 days/year); and (3) cannabis use disorder diagnosis, based on DSM-IV criteria. Covariates included program type, age group and state-level characteristics throughout the study period. Adults 26+ years of age living in states with non-medical MML programs increased past-month marijuana use 1.46% (from 4.13 to 6.59%, P = 0.01), skewing towards greater heavy marijuana by 2.36% (from 14.94 to 17.30, P = 0.09) after MMLs were enacted. However, no associated increase in the prevalence of cannabis use disorder was found during the study period. Our findings do not show increases in prevalence of marijuana use among adults in states with medicalized MML programs. Additionally, there were no increases in adolescent or young adult marijuana outcomes following MML passage, irrespective of program type. Non-medical marijuana laws enacted in US states are associated with increased marijuana use, but only among adults aged 26+ years. Researchers and

Recreational Marijuana Use and Acute Myocardial Infarction: Insights from Nationwide Inpatient Sample in the United States

PubMed Central

Patel, Upenkumar; Sharma, Shobhit; Amin, Parth; Bhuva, Rushikkumar; Patel, Malav S; Sharma, Nitin; Shah, Manan; Patel, Smit; Savani, Sejal; Batra, Neha; Kumar, Gautam

2017-01-01

Background Marijuana is a widely used recreational substance. Few cases have been reported of acute myocardial infarction following marijuana use. To our knowledge, this is the first ever study analyzing the lifetime odds of acute myocardial infarction (AMI) with marijuana use and the outcomes in AMI patients with versus without marijuana use. Methods We queried the 2010-2014 National Inpatient Sample (NIS) database for 11-70-year-old AMI patients. Pearson Chi-square test for categorical variables and Student T-test for continuous variables were used to compare the baseline demographic and hospital characteristics between two groups (without vs. with marijuana) of AMI patients. The univariate and multivariate analyses were used to assess and compare the clinical outcomes between two groups. We used Cochran–Armitage test to measure the trends. All statistical analyses were executed by IBM SPSS Statistics 22.0 (IBM Corp., Armonk, NY). We used weighted data to produce national estimates in our study. Results Out of 2,451,933 weighted hospitalized AMI patients, 35,771 patients with a history of marijuana and 2,416,162 patients without a history of marijuana use were identified. The AMI-marijuana group consisted more of younger, male, African American patients. The length of stay and mortality rate were lower in the AMI-marijuana group with more patients being discharged against medical advice. Multivariable analysis showed that marijuana use was a significant risk factor for AMI development when adjusted for age, sex, race (adjusted OR 1.079, 95% CI 1.065-1.093, p<0.001); adjusted for age, female, race, smoking, cocaine abuse (adjusted OR 1.041, 95% CI 1.027-1.054, p<0.001); and also when adjusted for age, female, race, payer status, smoking, cocaine abuse, amphetamine abuse and alcohol abuse (adjusted OR: 1.031, 95% CI: 1.018-1.045, p<0.001). Complications such as respiratory failure (OR 18.9, CI 15.6-23.0, p<0.001), cerebrovascular disease (OR 9.0, CI 7.0-11.7, p<0

An Analysis of Applicants Presenting to a Medical Marijuana Specialty Practice in California

PubMed Central

Nunberg, Helen; Kilmer, Beau; Pacula, Rosalie Liccardo; Burgdorf, James

2011-01-01

For more than a decade, medical marijuana has been at the forefront of the marijuana policy debate in the United States. Fourteen states allow physicians to recommend marijuana or provide a legal defense for patients and physicians if prosecuted in state courts; however, little is known about those individuals using marijuana for medicinal purposes and the symptoms they use it for. This study provides descriptive information from 1,655 patients seeking a physician’s recommendation for medical marijuana, the conditions for which they seek treatment, and the diagnoses made by the physicians. It conducts a systematic analysis of physician records and patient questionnaires obtained from consecutive patients being seen during a three month period at nine medical marijuana evaluation clinics belonging to a select medical group operating throughout the State of California. While this study is not representative of all medical marijuana users in California, it provides novel insights about an important population being affected by this policy. PMID:23750291

Gateway to curiosity: Medical marijuana ads and intention and use during middle school.

PubMed

D'Amico, Elizabeth J; Miles, Jeremy N V; Tucker, Joan S

2015-09-01

Over the past several years, medical marijuana has received increased attention in the media, and marijuana use has increased across the United States. Studies suggest that as marijuana has become more accessible and adults have become more tolerant regarding marijuana use, adolescents perceive marijuana as more beneficial and are more likely to use if they are living in an environment that is more tolerant of marijuana use. One factor that may influence adolescents' perceptions about marijuana and marijuana use is their exposure to advertising of this product. We surveyed sixth- to eighth-grade youth in 2010 and 2011 in 16 middle schools in Southern California (n = 8,214; 50% male; 52% Hispanic; mean age = 13 years) and assessed exposure to advertising for medical marijuana, marijuana intentions, and marijuana use. Cross-lagged regressions showed a reciprocal association of advertising exposure with marijuana use and intentions during middle school. Greater initial medical marijuana advertising exposure was significantly associated with a higher probability of marijuana use and stronger intentions to use 1 year later, and initial marijuana use and stronger intentions to use were associated with greater medical marijuana advertising exposure 1 year later. Prevention programs need to better explain medical marijuana to youth, providing information on the context for proper medical use of this drug and the potential harms from use during this developmental period. Furthermore, as this is a new frontier, it is important to consider regulating medical marijuana advertisements, as is currently done for alcohol and tobacco products. (c) 2015 APA, all rights reserved).

Alcohol use potentiates marijuana problem severity in young adult women.

PubMed

Stein, Michael D; Caviness, Celeste M; Anderson, Bradley J

2014-01-01

Most young adult women who smoke marijuana also drink alcohol. Marijuana-related problems are associated with marijuana use frequency. We hypothesized that increased alcohol use frequency potentiates the association between frequency of marijuana use and marijuana-related problem severity. We recruited women aged 18 to 24 who smoked marijuana at least monthly and were not treatment seeking. Marijuana and alcohol use were measured using the timeline follow-back method. Problems associated with marijuana use were assessed using the Marijuana Problems Scale. Participants (n = 332) averaged 20.5 ± 1.8 years of age, were 66.7% non-Hispanic White, and reported using marijuana on 51.5 ± 30.6 and alcohol on 18.9 ± 16.8 of the 90 previous days. Controlling for education, ethnicity, years of marijuana use, and other drug use, frequency of marijuana use (b = .22; p < .01) and frequency of alcohol use (b = 0.13; p < .05) had significant, positive effects on marijuana problem severity. In a separate multivariate model, the linear by linear interaction of marijuana by alcohol use frequency was significant (b = 0.18; p < .01), consistent with the hypothesis. Concurrent alcohol use impacts the experience of negative consequences from marijuana use in a community sample of young women. Discussions of marijuana use in young adults should consider the possible potentiating effects of alcohol use. Copyright © 2014 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

Caring for Young Children Exposed to Marijuana.

PubMed

Ruiz, Natasha M; Shapiro, Susan E

This article reviews the research report, Marijuana Exposure Among Children Younger Than Six Years in the United States (), and, using a case study approach, applies the findings to advanced practice registered nurses. B. extracted data from the National Poison Data System showing an increasing trend in marijuana exposure in children, especially in states where marijuana has been legalized for either medicinal use or recreational use. Advanced practice registered nurses need to be comfortable recognizing and managing marijuana intoxication in the pediatric population, as well as educating parents in providing safe environments for their children.

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

Medicinal marijuana for epilepsy: a case series study.

PubMed

Ladino, Lady Diana; Hernández-Ronquillo, Lizbeth; Téllez-Zenteno, José Francisco

2014-11-01

To describe the social, clinical and use-patterns characteristics of medicinal marijuana use among patients with epilepsy (PWEs). Eighteen PWEs with prescriptions for medicinal marijuana from a Canadian adult-epilepsy clinic were included in this study. Eighteen patients had a prescription of medicinal marijuana from a total population of 800 PWEs in our center (2.2%). Mean age of patients was 30±7.4 (19-50) years. Twelve (67%) patients were males. Eleven (61%) patients had drug-resistant epilepsy. Eleven (61%) patients suffered a psychiatric comorbidity and reported the use of illicit substances or heavy alcohol or tobacco consumption. Only two (11%) patients were married; the rest of patients (89%) were single or divorced. The drug use pattern was similar among patients. All patients asked for marijuana permission in the epilepsy clinic. Most (83%) had a previous history of marijuana smoking, with a mean of 6.6±3 (1-15) years. The mean consumption dose was 2.05±1.8 (0.5-8) grams per day. Ten (56%) patients reported withdrawal seizure exacerbation when they stopped the marijuana. Only two patients (11%) reported side effects, and all patients found medicinal marijuana very helpful for seizure control and improvement of mood disorder. PWEs using medicinal marijuana have a common profile. They are usually young single men with drug-resistant epilepsy and psychiatric comorbidity. Most used marijuana before formal prescription and all believe the drug was effective on their seizure control. Because of the concurrent use of other antiseizure medications, it is complex to estimate the actual effect of marijuana.

Using deviance regulation theory to target marijuana use intentions among college students.

PubMed

Dvorak, Robert D; Raeder, Cody A; Kramer, Matthew P; Sargent, Emily; Stevenson, Brittany L; Helmy, Mai

2018-02-01

Several large epidemiological studies have shown increasing trends on a number of indices of marijuana use among college age samples. This may be due to changing attitudes about marijuana use linked to legalization efforts. Interventions that can target problematic use on a broad scale are lacking. Recent research has shown that deviance regulation theory (DRT) can be used to design effective web-based substance use interventions. DRT relies on the interplay between perceived norms and an appropriately framed message about the given behavior. The current study examines the use of DRT to change marijuana use intentions. Participants (n = 694 college students) completed measures of marijuana use and marijuana use norms. They were then assigned to receive a positively framed message about marijuana abstainers or a negatively framed message about marijuana users. Following the manipulation, participants rated intentions to use marijuana over the next three months. Consistent with DRT, there was an interaction between message frame and marijuana use norms. The positive frame attenuated the association between marijuana use norms and use intentions. A negative frame resulted in the lowest levels of use intentions among those with low use norms. Results suggest that DRT may be used to modify use intentions in college students, a population that has shown increasing rates of use. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Attitudes towards drug legalization among drug users.

PubMed

Trevino, Roberto A; Richard, Alan J

2002-01-01

Research shows that support for legalization of drugs varies significantly among different sociodemographic and political groups. Yet there is little research examining the degree of support for legalization of drugs among drug users. This paper examines how frequency and type of drug use affect the support for legalization of drugs after adjusting for the effects of political affiliation and sociodemographic characteristics. A sample of 188 drug users and non-drug users were asked whether they would support the legalization of marijuana, cocaine, and heroin. Respondents reported their use of marijuana, crack, cocaine, heroin, speedball, and/or methamphetamines during the previous 30 days. Support for legalization of drugs was analyzed by estimating three separate logistic regressions. The results showed that the support for the legalization of drugs depended on the definition of "drug user" and the type of drug. In general, however, the results showed that marijuana users were more likely to support legalizing marijuana, but they were less likely to support the legalization of cocaine and heroin. On the other hand, users of crack, cocaine, heroin, speedball, and/or methamphetamines were more likely to support legalizing all drugs including cocaine and heroin.

Marijuana and tobacco co-use among a nationally representative sample of US pregnant and non-pregnant women: 2005-2014 National Survey on Drug Use and Health findings.

PubMed

Coleman-Cowger, Victoria H; Schauer, Gillian L; Peters, Erica N

2017-08-01

Marijuana and tobacco are the most commonly used illicit and licit drugs during pregnancy. This study aimed to examine a nationally representative sample of US pregnant women and to: (1) determine the prevalence of past month marijuana and tobacco co-use, (2) identify characteristics that distinguish marijuana and tobacco co-users from users of marijuana only, tobacco only, or neither, and (3) compare characteristics that differ between pregnant and non-pregnant co-users of marijuana and tobacco. Data were obtained from 497,218 US women (8721 pregnant) ages 12-49 who participated in the 2005-2014 National Survey on Drug Use and Health. Prevalence and demographic and substance use characteristics were compared across groups using weighted estimates and chi-squared tests. Multinomial logistic regression identified demographic and substance use correlates of co-use. Co-use among pregnant and non-pregnant women was significantly more prevalent than marijuana-only use but was less common than tobacco-only use. In unadjusted frequencies, pregnant co-users significantly differed from non-pregnant co-users across several domains. Among pregnant women, multivariate correlates of co-use of tobacco and marijuana vs. tobacco-only use were ages 12-17, non-Hispanic black race, Hispanic ethnicity, and past month polytobacco, any alcohol, and other drug use (all adjusted odds ratios≥2.0). In this first examination of the prevalence and correlates of co-use of marijuana and tobacco among a nationally representative group of pregnant women, pregnant co-users were more likely to report other high risk behaviors compared with non-pregnant co-users and users of a single substance, suggesting disparities worthy of further investigation. Copyright © 2017 Elsevier B.V. All rights reserved.

Effectiveness of Motivational Incentives for Adolescent Marijuana Users in a School-Based Intervention.

PubMed

Stewart, David G; Felleman, Benjamin I; Arger, Christopher A

2015-11-01

This study examined whether adolescents receiving Motivational Interviewing (MI) intervention have different outcomes compared to those receiving Motivational Incentives (Motivational Interviewing combined with Contingency Management; MI+CM). A total of 136 adolescents (from a parent study of 220 adolescents) with problematic substance use were recruited from 8 high schools in Washington State, where they completed either 8-weeks of MI or MI+CM. Frequency of marijuana use was assessed at baseline, at the end-of-treatment, and at 16-week follow-up. A balanced and matched sample was created using propensity scores, then analyzed using Hierarchical Linear Modeling (HLM). Multilevel regression analyses revealed that adolescents who received MI+CM exhibited a greater reduction in use across time (p<.05). Reductions at the end-of-treatment were greater for the MI+CM condition (Cohen's d=-.82) compared to MI alone (Cohen's d=-.33), but did not differ at 16-week follow-up. Adolescents receiving MI+CM showed significantly fewer negative consequences of marijuana use at the end-of-treatment (t1, 124=2.26, p<.05), higher use of coping strategies (t1, 124=3.01, p<.01), and increased likelihood to attend additional treatment for substance use (χ2 1, 124=4.12 p<.05), though hypothesized improvements in motivation and school attendance were not found. Use of coping strategies at the end-of-treatment had a significant indirect effect on the relationship between the intervention condition and marijuana use at the end-of-treatment (F3, 121=10.20, R2=.20, p<.01). These results suggest that the inclusion of contingencies into adolescent marijuana treatment decreases the end-of-treatment frequency of marijuana use and related consequences while increasing the use of coping strategies and the pursuit of additional treatment. Copyright © 2015 Elsevier Inc. All rights reserved.

Is medical marijuana legalisation possible in Poland?

PubMed

Rogowska-Szadkowska, Dorota; Strumiło, Julia; Chlabicz, Sławomir

2018-03-01

In some countries of the world it is legal to use plant-based marijuana for therapeutic purposes. When we had learned that 7,000 petitioners (including doctors) signed the petition to enable access to marijuana for patients in the Czech Republic, we decided to examine the knowledge about marijuana's medical properties among Polish medical students. Anonymous questionnaire study was conducted on a group of 181 of students of the last (sixth) year of medical school. It was demonstrated that students are not provided with sufficient information about therapeutic administration of plant-based marijuana during medical studies. The majority of interviewees mentioned only one indication for medical marijuana use. All students did not interchange medical conditions for which marijuana is used in 30 USA states or Canada. Marijuana smoking for medical purposes differs from recreational smoking, and its effect does not depend on occurrence of symptoms from the central nervous system. Few studies, that were carried out along with numerous previously unreported cases of patients, demonstrated that plant-derived marijuana had therapeutic effect on many diseases where conventional medicine was of no help. All doctors, including medical students, should receive more information about the therapeutic properties of marijuana. Copyright© by the National Institute of Public Health, Prague 2018.

The Formation of Marijuana Risk Perception in a Population of Substance Abusing Patients.

PubMed

Wilkinson, Samuel T; van Schalkwyk, Gerrit I; Davidson, Larry; D'Souza, Deepak C

2016-03-01

Risk perception has been shown to be protective with regard to marijuana use. Notably, the risk perception of marijuana in individuals with substance abuse problems varies significantly from that of the general public. Understanding how risk perception is formed in substance users could explain these differences and help predict the consequences of policy changes. Using this framework, we explored risk perception and its formation in a sample of substance abusing veterans. Semi-structured interviews were conducted with veterans who were receiving treatment for substance abuse. Interviews were recorded digitally, transcribed verbatim, and analyzed using inductive thematic analysis. A prominent perspective among the 31 participants was that marijuana is significantly different from other drugs because it is safe, not addictive, not associated with physical withdrawal, and has less overt behavioral effects than other substances. Many of these participants drew upon their own innocuous experiences with the drug in developing this perspective, more so than information from any other source. A contrasting narrative emphasized marijuana's capacity to cause negative social consequences, act as a gateway to the use of other, more harmful substances, and cause paranoia or worsen psychosis. In conclusion, individual experience with marijuana featured more prominently in informing risk perception than any other source of information. Our results and previous literature suggest that the significant disconnect between the individual experiences of substance users and the current clinical and legal policy towards marijuana may weaken the legitimacy of public policy or the authority of the medical community.

Marijuana (Weed, Pot) Facts

MedlinePlus

... That People Abuse » Marijuana (Weed, Pot) Facts Marijuana (Weed, Pot) Facts Listen Marijuana is a green, brown, or gray mix of dried, shredded leaves and flowers from the marijuana plant. Marijuana can be rolled up and smoked ...

How does state marijuana policy affect U.S. youth? Medical marijuana laws, marijuana use and perceived harmfulness: 1991–2014

PubMed Central

Keyes, Katherine M.; Wall, Melanie; Cerdá, Magdalena; Schulenberg, John; O’Malley, Patrick M.; Galea, Sandro; Feng, Tianshu; Hasin, Deborah S.

2016-01-01

Aims To test, among US students: 1) whether perceived harmfulness of marijuana has changed over time, 2) whether perceived harmfulness of marijuana changed post-passage of state medical marijuana laws (MML) compared with pre-passage; 3) whether perceived harmfulness of marijuana mediates and/or modifies the relation between MML and marijuana use as a function of grade level. Design Cross-sectional nationally-representative surveys of U.S. students, conducted annually, 1991–2014, in the Monitoring The Future study. Setting Surveys conducted in schools in all coterminous states; 21 states passed MML between 1996–2014. Participants The sample included 1,134,734 adolescents in 8th, 10th, and 12th grades. Measures State passage of MML; perceived harmfulness of marijuana use (perceiving great or moderate risk to health from smoking marijuana occasionally versus slight or no risk); and marijuana use (prior 30 days). Data were analyzed using time-varying multi-level regression modeling. Findings Perceived harmfulness of marijuana significantly decreased since 1991 (from an estimated 84.0% in 1991 to 53.8% in 2014, p<0.01). Across time, perceived harmfulness was lower in states that passed MML (OR=0.86, 95% C.I. 0.75–0.97). In states with MML, perceived harmfulness of marijuana increased among 8th graders after MML passage (OR=1.21, 95% C.I. 1.08–1.36), while marijuana use decreased (OR=0.81, 95% C.I. 0.72–0.92). Results were null for other grades, and for all grades combined. Increases in perceived harmfulness among 8th graders after MML passage was associated with ~33% of the decrease in use. When adolescents were stratified by perceived harmfulness, use in 8th graders decreased to a greater extent among those who perceived marijuana as harmful. Conclusions While perceived harmfulness of marijuana use is decreasing nationally among adolescents, passage of medical marijuana laws is associated with increases in perceived harmfulness among young adolescents, and

The Self-Report Habit Index: Assessing habitual marijuana, alcohol, e-cigarette, and cigarette use.

PubMed

Morean, Meghan E; DeMartini, Kelly S; Foster, Dawn; Patock-Peckham, Julie; Garrison, Kathleen A; Corlett, Philip R; Krystal, John H; Krishan-Sarin, Suchitra; O'Malley, Stephanie S

2018-05-01

Substance use is partially driven by habitual processes that occur automatically in response to environmental cues and may be central to users' identities. This study was designed to validate the Self-Report Habit Index (SRHI) for assessing habitual marijuana, alcohol, cigarette, and e-cigarette use. We examined the SRHI's psychometrics in separate samples of adult marijuana (Ns = 189;170), alcohol (Ns = 100;133), cigarette (Ns = 58;371), and e-cigarette (N = 239) users. A 6-item, single-factor solution evidenced good fit across substances (CFI marijuana/alcohol/cigarettes/e-cigarettes = 0.996/0.997/0.996/0.994, RMSEA = 0.046/0.047/0.067/0.068, SRMR = 0.017/0.017/0.010/0.015) and internal consistency (α = 0.88/0.94/0.95/0.91). The SRHI was scalar invariant for sex and race. However, independent-samples t-tests indicated only that women endorsed stronger habitual e-cigarette use and that men endorsed stronger habitual marijuana use. The SRHI also was scalar invariant by product type in dual-users (cigarettes/e-cigarettes[N = 371]; alcohol/cigarettes [n = 58]), although differences in habit strength only were observed for cigarettes versus e-cigarettes, with dual-users reporting stronger habitual cigarette use. Finally, the SRHI predicted frequency of marijuana, alcohol, cigarette, and e-cigarette use (n p 2 [marijuana/alcohol/cigarettes/e-cigarettes] = 0.37/0.48/0.31/0.17) and quantity of alcohol and cigarette use (n p 2  = 0.43/0.33). The SRHI is a psychometrically sound measure of adults' habitual substance use. The SRHI detected mean differences by sex and substance type and predicted the frequency of using each substance. Future research should determine if the SRHI is appropriate for use with other substances or age groups (e.g., adolescents), how it relates to task-based, behavioral measures of habit strength, and the degree to which habit predicts the development or maintenance of addiction. Copyright © 2018

Tobacco and Marijuana Initiation Among African American and White Young Adults

PubMed Central

Kennedy, Sara M.; Patel, Roshni P.; Cheh, Paul; Hsia, Jason; Rolle, Italia V.

2016-01-01

Introduction African American youth use marijuana at similar rates and tobacco at lower rates compared with white youth; however, in adulthood, tobacco use is similar. Tobacco and marijuana use are closely associated; differing initiation patterns may contribute to observed racial differences in tobacco prevalence by age. Therefore, it is important to assess tobacco and marijuana initiation patterns by race. Methods Data were obtained from 56,555 adults aged 18–25 who completed the 2005–2012 National Survey on Drug Use and Health. The analysis was restricted to those who reported ever use of marijuana and combustible tobacco (cigarettes and/or cigars). Three mutually exclusive categories of initiation patterns were evaluated: use of marijuana before tobacco; marijuana and tobacco at the same age; and tobacco before marijuana. Multivariable regression models were used to assess changes over time and compare these outcomes by race while controlling for sociodemographics, risk perceptions, and current substance use. Results In 2005, 26.6% of African American and 14.3% of white young adults used marijuana before tobacco, compared with 41.5% of African American and 24.0% of white young adults in 2012 (P < .001). Overall, African American young adults had greater odds of using marijuana before tobacco (AOR = 1.79; 95% CI: 1.67, 1.91) compared with whites. Conclusion African American young adults were more likely than whites to use marijuana before tobacco and both groups were increasingly likely to use marijuana before tobacco over time. A greater understanding of how marijuana initiation interacts with tobacco initiation could inform more effective tobacco and marijuana use prevention efforts. Implications Among ever users of combustible tobacco and marijuana, greater proportions of African American young adults used marijuana before tobacco or at the same age than their white counterparts. Moreover, both African Americans and whites were more likely to use

Predictors of Adult Marijuana Use Among Parents and Nonparents.

PubMed

Epstein, Marina; Bailey, Jennifer A; Steeger, Christine M; Hill, Karl G; Skinner, Martie L

2018-02-01

The current study examined predictors of marijuana use among adults, including subsamples of adults who are actively parenting (i.e., have regular face-to-face contact with a child) and those who have no children. Participants were a community sample of 808 adults and two subsamples drawn from the full group: 383 adults who were actively parenting and 135 who had no children. Multilevel models examined predictors of marijuana use in these three groups from ages 27 to 39. Becoming a parent was associated with a decrease in marijuana use. Regular marijuana use in young adulthood (ages 21-24), partner marijuana use, and pro-marijuana attitudes increased the likelihood of past-year marijuana use among all participants. Being a primary caregiver (among parents) was associated with less marijuana use. Overall, predictors of marijuana use were similar for all adults, regardless of parenting status. Study results suggest that the onset of parenthood alone may be insufficient to reduce adult marijuana use. Instead, preventive intervention targets may include changing adult pro-marijuana attitudes and addressing marijuana use behaviors of live-in partners. Lastly, universal approaches targeting parents and nonparents may be effective for general adult samples.

Gateway to Curiosity: Medical Marijuana Ads and Intention and Use during Middle School

PubMed Central

D’Amico, Elizabeth J.; Miles, Jeremy N.V.; Tucker, Joan S.

2015-01-01

Over the past several years, medical marijuana has received increased attention in the media, and marijuana use has increased across the United States. Studies suggest that as marijuana has become more accessible and adults have become more tolerant regarding marijuana use, adolescents perceive marijuana as more beneficial and are more likely to use if they are living in an environment that is more tolerant of marijuana use. One factor that may influence adolescents’ perceptions about marijuana and marijuana use is their exposure to advertising of this product. We surveyed 6th–8th grade youth in 2010 and 2011 in 16 middle schools in southern California (n= 8214; 50% male; 52% Hispanic; mean age = 13) and assessed exposure to advertising for medical marijuana, marijuana intentions and marijuana use. Cross-lagged regressions showed a reciprocal association of advertising exposure with marijuana use and intentions during middle school. Greater initial medical marijuana advertising exposure was significantly associated with a higher probability of marijuana use and stronger intentions to use one year later, and initial marijuana use and stronger intentions to use were associated with greater medical marijuana advertising exposure one year later. Prevention programs need to better explain medical marijuana to youth, providing information on the context for proper medical use of this drug and the potential harms from use during this developmental period. Furthermore, as this is a new frontier, it is important to consider regulating medical marijuana advertisements, as is currently done for alcohol and tobacco products. PMID:26030167

Clearing the haze: the complexities and challenges of research on state marijuana laws.

PubMed

Choo, Esther K; Emery, Sherry L

2017-04-01

As states increasingly liberalize marijuana laws, high-quality research is needed that will inform the public and policymakers about the health and societal impact of these laws. However, there are many challenges to studying marijuana policy, including the heterogeneity of the drug and its use, the variability in the laws and their implementation from state to state, the need to capture a wide variety of relevant outcomes, and the poorly understood influence of marijuana commercialization. Furthermore, current instruments generally fail to distinguish between types of users and lack accurate and detailed measures of use. This review provides a background on marijuana laws in the United States and an overview of existing policy research, discusses methodological considerations when planning analysis of state marijuana laws, and highlights specific topics needing further development and investigation. © 2016 New York Academy of Sciences.

The association between alcohol, marijuana use, and new and emerging tobacco products in a young adult population.

PubMed

Cohn, Amy; Villanti, Andrea; Richardson, Amanda; Rath, Jessica M; Williams, Valerie; Stanton, Cassandra; Mermelstein, Robin

2015-09-01

Young adults have the highest rates of alcohol, tobacco, and other drug use relative to any other age group. Few studies have examined the co-occurrence of substance use with new and emerging tobacco products in this vulnerable group, or the underlying personality factors that may explain these associations. To address this gap, this study examined the association of current alcohol and marijuana use with the use of cigarettes and emerging tobacco products in a nationally representative sample of young adults. Data were drawn from 18 to 24year olds in Wave 4 (January 2013; n=1609) of the Legacy Young Adult Cohort, a nationally-representative sample of men and women. Never, ever (lifetime), and past 30-day use of little cigars/cigarillos (LCCs), hookah, e-cigarettes, and cigarettes were assessed separately in current (everyday or some days) alcohol and marijuana users. Using weighted estimates, multivariable multinomial logistic regression models showed that current alcohol and marijuana use were associated with lifetime and past 30-day use of cigarettes, LCCs, e-cigarettes, and hookah, with different magnitudes of association found across each product. Post-hoc exploratory analyses showed that sensation-seeking traits moderated the relationship of alcohol (but not marijuana) use to current use of select tobacco products. Marijuana and alcohol use may enhance risk for emerging tobacco products use in young adulthood. Prevention and intervention programs may need to target poly-use of alcohol, marijuana, and tobacco rather than focusing on a single risk behavior during these critical years. Copyright © 2015 Elsevier Ltd. All rights reserved.

Marijuana-Related Posts on Instagram.

PubMed

Cavazos-Rehg, Patricia A; Krauss, Melissa J; Sowles, Shaina J; Bierut, Laura J

2016-08-01

Instagram is a highly visual social networking site whose audience continues to grow, especially among young adults. In the present study, we examine marijuana-related content on Instagram to better understand the varied types of marijuana-related social networking occurring on this popular social media platform. We collected 417,561 Instagram posts with marijuana-related hashtags from November 29 to December 12, 2014. We assessed content of a random sample (n = 5000) of these posts with marijuana-related hashtags. Approximately 2136 (43 %) were explicit about marijuana and further analyzed. Of the 2136 marijuana-related posts, images of marijuana were common (n = 1568). Among these 1568 marijuana images, traditional forms (i.e., buds/leaves) were the most common (63 %), followed by some novel forms of marijuana, including marijuana concentrates (20 %). Among the 568 posts that displayed marijuana being ingested, 20 % showed someone dabbing marijuana concentrates. Marijuana-related advertisements were also observed among the 2136 marijuana-related posts (9 %). Our findings signal the promotion of marijuana use in its traditional plant-based form; trendy and novel modes of marijuana ingestion were also endorsed. This content along with the explicit marketing of marijuana that we observed on Instagram have potential to influence social norms surrounding marijuana use.

Marijuana-Related Posts on Instagram

PubMed Central

Krauss, Melissa J.; Sowles, Shaina J.; Bierut, Laura J.

2016-01-01

Instagram is a highly visual social networking site whose audience continues to grow, especially among young adults. In the present study, we examine marijuana-related content on Instagram to better understand the varied types of marijuana-related social networking occurring on this popular social media platform. We collected 417,561 Instagram posts with marijuana-related hashtags from November 29 to December 12, 2014. We assessed content of a random sample (n = 5000) of these posts with marijuana-related hashtags. Approximately 2136 (43 %) were explicit about marijuana and further analyzed. Of the 2136 marijuana-related posts, images of marijuana were common (n = 1568). Among these 1568 marijuana images, traditional forms (i.e., buds/leaves) were the most common (63 %), followed by some novel forms of marijuana, including marijuana concentrates (20 %). Among the 568 posts that displayed marijuana being ingested, 20 % showed someone dabbing marijuana concentrates. Marijuana-related advertisements were also observed among the 2136 marijuana-related posts (9 %). Our findings signal the promotion of marijuana use in its traditional plant-based form; trendy and novel modes of marijuana ingestion were also endorsed. This content along with the explicit marketing of marijuana that we observed on Instagram have potential to influence social norms surrounding marijuana use. PMID:27262456

Residential Mobility, Transience, Depression, and Marijuana Use Initiation Among Adolescents and Young Adults

PubMed Central

Glasheen, Cristie; Forman-Hoffman, Valerie L; Williams, Jason

2017-01-01

Marijuana use initiation is associated with numerous health and behavioral consequences, particularly among young adolescents. Finding easily identifiable risk markers for marijuana initiation is an important step for targeting primary and secondary prevention efforts. This study used data from the 2010–2014 National Survey on Drug Use and Health to evaluate the association between residential mobility (no mobility, low mobility, high mobility [ie, transience]), and major depressive episode(s) (MDE) on marijuana initiation among adolescents (12–17) and young adults (18–20). Age-stratified logistic regression models indicated that among 12- to 13-year-old adolescents, mobility in the past 5 years and past year MDE have a multiplicative effect on the odds of past year marijuana initiation. Among adolescents aged 14 to 15 years, both mobility and MDE were independently associated with marijuana initiation, but there was no interaction. Among older adolescents (aged 16–17 years), only transience (⩾3 moves in the past 5 years) was associated with marijuana use initiation, and although MDE was significantly associated with marijuana initiation, there was no interaction with mobility. Among young adults, mobility was not associated with marijuana initiation. Residential mobility among young adolescents is an easily identifiable risk marker that may serve as an indicator for physical and mental health professionals, school personnel, and parents to use in targeting both depression and marijuana prevention efforts. PMID:28607541

Marijuana Use and New Concerns about Medical Marijuana. E-Fact Sheet

ERIC Educational Resources Information Center

Higher Education Center for Alcohol, Drug Abuse, and Violence Prevention, 2010

2010-01-01

While alcohol remains the drug of choice among college students, marijuana ranks number two with 32 percent reporting using marijuana in 2008. That's a modest decline from 2001, when 36 percent of college students reported marijuana use. While levels of marijuana use by students are determined through a number of national and local surveys, no…

Association Between Lifetime Marijuana Use and Cognitive Function in Middle Age: The Coronary Artery Risk Development in Young Adults (CARDIA) Study.

PubMed

Auer, Reto; Vittinghoff, Eric; Yaffe, Kristine; Künzi, Arnaud; Kertesz, Stefan G; Levine, Deborah A; Albanese, Emiliano; Whitmer, Rachel A; Jacobs, David R; Sidney, Stephen; Glymour, M Maria; Pletcher, Mark J

2016-03-01

Marijuana use is increasingly common in the United States. It is unclear whether it has long-term effects on memory and other domains of cognitive function. To study the association between cumulative lifetime exposure to marijuana use and cognitive performance in middle age. We used data from the Coronary Artery Risk Development in Young Adults (CARDIA) study, a cohort of 5115 black and white men and women aged 18 to 30 years at baseline from March 25, 1985, to June 7, 1986 (year 0), and followed up over 25 years from June 7, 1986, to August 31, 2011, to estimate cumulative years of exposure to marijuana (1 year = 365 days of marijuana use) using repeated measures and to assess associations with cognitive function at year 25. Linear regression was used to adjust for demographic factors, cardiovascular risk factors, tobacco smoking, use of alcohol and illicit drugs, physical activity, depression, and results of the mirror star tracing test (a measure of cognitive function) at year 2. Data analysis was conducted from June 7, 1986, to August 31, 2011. Three domains of cognitive function were assessed at year 25 using the Rey Auditory Verbal Learning Test (verbal memory), the Digit Symbol Substitution Test (processing speed), and the Stroop Interference Test (executive function). Among 3385 participants with cognitive function measurements at the year 25 visit, 2852 (84.3%) reported past marijuana use, but only 392 (11.6%) continued to use marijuana into middle age. Current use of marijuana was associated with worse verbal memory and processing speed; cumulative lifetime exposure was associated with worse performance in all 3 domains of cognitive function. After excluding current users and adjusting for potential confounders, cumulative lifetime exposure to marijuana remained significantly associated with worse verbal memory. For each 5 years of past exposure, verbal memory was 0.13 standardized units lower (95% CI, -0.24 to -0.02; P = .02), corresponding to a mean of

Washington State recreational marijuana legalization: parent and adolescent perceptions, knowledge, and discussions in a sample of low-income families.

PubMed

Mason, W A; Hanson, Koren; Fleming, Charles B; Ringle, Jay L; Haggerty, Kevin P

2015-04-01

In November 2012, Washington State and Colorado became the first states in the United States to legalize recreational marijuana use for adults, and Uruguay became the first country to allow the cultivation, distribution, possession, and use of marijuana. One possible consequence of these changes is increased adolescent marijuana use. Parents may mitigate this adverse consequence; however, whether parents and adolescents have accurate knowledge about the laws and are discussing marijuana use in light of the law changes is unknown. We examine perceptions, knowledge, and parent-child discussions about Washington State's recreational marijuana law in a sample of low-income families. Participants were a subset of families (n = 115) in an ongoing study that originally recruited parents and adolescents from middle schools in Tacoma, Washington. In summer 2013, when students were entering the 11(th) grade, students and their parents were asked questions about the recreational marijuana law. Participants perceived that their marijuana-related attitudes and behaviors changed little as a result of the law, and displayed uncertainty about what is legal and illegal. Most parents reported discussing the new law with their children but only occasionally, and conversations emphasized household rules, particularly among parent lifetime marijuana users compared to non-users. Conclusions/Importance: Results suggest that there should be a public health campaign focused on families that provides clear information about the recreational marijuana laws.

Medical marijuana.

PubMed

Marmor, J B

1998-06-01

Although many clinical studies suggest the medical utility of marijuana for some conditions, the scientific evidence is weak. Many patients in California are self-medicating with marijuana, and physicians need data to assess the risks and benefits. The only reasonable solution to this problem is to encourage research on the medical effects of marijuana. The current regulatory system should be modified to remove barriers to clinical research with marijuana. The NIH panel has identified several conditions for which there may be therapeutic benefit from marijuana use and that merit further research. Marijuana should be held to the same evaluation standards of safety and efficacy as other drugs (a major flaw in Proposition 215) but should not have to be proved better than current medications for its use to be adopted. The therapeutic window for marijuana and THC between desired effect and unpleasant side effects is narrow and is a major reason for discontinuing use. Although the inhaled route of administration has the benefit of allowing patients to self-titrate the dose, the smoking of crude plant material is problematic. The NIH panel recommended that a high priority be given to the development of a controlled inhaled form of THC. The presence of a naturally occurring cannabinoid-receptor system in the brain suggests that research on selective analogues of THC may be useful to enhance its therapeutic effects and minimize adverse effects.

Medical and recreational marijuana: commentary and review of the literature.

PubMed

Wilkinson, Samuel T

2013-01-01

Recent years have seen substantial shifts in cultural attitudes towards marijuana for medical and recreational use. Potential problems with the approval, production, dispensation, route of administration, and negative health effects of medical and recreational marijuana are reviewed. Medical marijuana should be subject to the same rigorous approval process as other medications prescribed by physicians. Legalizing recreational marijuana may have negative public health effects.

Momentary positive and negative affect preceding marijuana use events in youth.

PubMed

Shrier, Lydia A; Ross, Craig S; Blood, Emily A

2014-09-01

ABSTRACT. among young people. This study examined how positive and negative affect differ before marijuana use compared with other times. Forty medical outpatients ages 15-24 years who used marijuana recreationally at least twice a week (M = 18.7 years; 58% female) reported momentary positive affect, negative affect, companionship, perceived ease of obtaining marijuana, and marijuana use several times a day for 2 weeks on a handheld computer. Mean momentary positive affect and negative affect scores in the 24 hours leading up to a marijuana use event (n = 294) were compared with affect scores in times further from subsequent use. Generalized estimating equation models considered as potential moderators perceived ease of obtaining marijuana and being with friends. Positive affect did not differ in the 24 hours before marijuana use compared with times further before use. Negative affect was significantly higher before marijuana use compared with other times. Being with friends and perceived easy marijuana availability did not moderate the associations. The association between negative affect and subsequent marijuana use was attenuated when negative affect was examined only for the moment just before use, suggesting that use may follow a period of increased negative affect. The findings support an affect regulation model for marijuana use among frequently using youth. Specifically, these youth may use marijuana to manage increased negative affect.

Medical Marijuana Use among Adolescents in Substance Abuse Treatment

ERIC Educational Resources Information Center

Salomonsen-Sautel, Stacy; Sakai, Joseph T.; Thurstone, Christian; Corley, Robin; Hopfer, Christian

2012-01-01

Objective: To assess the prevalence and frequency of medical marijuana diversion and use among adolescents in substance abuse treatment and to identify factors related to their medical marijuana use. Method: This study calculated the prevalence and frequency of diverted medical marijuana use among adolescents (n = 164), ages 14-18 years (mean age…

Substance use - marijuana

MedlinePlus

Substance abuse - marijuana; Drug abuse - marijuana; Drug use - marijuana; Cannabis; Grass; Hashish; Mary Jane; Pot; Weed ... several minutes. If you eat foods containing the drug as an ingredient, such as brownies, you may ...

Facts on Marijuana. Clearinghouse Fact Sheet.

ERIC Educational Resources Information Center

Brick, John

Marijuana or Cannabis is a weed which grows in many different parts of the world. The plant may be altered into different forms to allow various forms of ingestion. Although marijuana's psychoactive properties have been known for almost 5,000 years, the plant first attracted public attention in the United States during the first half of this…

Patterns of substance use, delinquency, and risk factors among adolescent inhalant users.

PubMed

Nakawaki, Brandon; Crano, William

2015-01-01

Despite insidious effects, use of inhalant substances by adolescents remains an understudied phenomenon. This research was designed to identify patterns of past year substance use and delinquency among adolescent inhalant users. The study used a sample of adolescent inhalant users (ages ranged from 12-17 years, n = 7,476) taken from a pooled sample of the 2002 through 2012 National Survey of Drug Use and Health (NSDUH). Three-step latent class analyses were conducted with past year substance use and delinquency behaviors as class indicators. Demographic and social covariates were included in the analyses. Analyses yielded a six-class solution comprised of classes of users characterized by low substance use/low delinquency, high substance use/low delinquency, low substance use/fighting, cigarettes/alcohol/marijuana, high substance use/high delinquency, and cigarettes/alcohol/ marijuana/opioids/moderate delinquency. Findings provide insight into the taxonomy of adolescent inhalant user heterogeneity, and may inform future efforts at detection and prevention of inhalant use by suggesting warning signs of co-occurring externalizing behaviors and possible indications of underlying internalized issues.

Tobacco and Marijuana Initiation Among African American and White Young Adults.

PubMed

Kennedy, Sara M; Patel, Roshni P; Cheh, Paul; Hsia, Jason; Rolle, Italia V

2016-04-01

African American youth use marijuana at similar rates and tobacco at lower rates compared with white youth; however, in adulthood, tobacco use is similar. Tobacco and marijuana use are closely associated; differing initiation patterns may contribute to observed racial differences in tobacco prevalence by age. Therefore, it is important to assess tobacco and marijuana initiation patterns by race. Data were obtained from 56,555 adults aged 18-25 who completed the 2005-2012 National Survey on Drug Use and Health. The analysis was restricted to those who reported ever use of marijuana and combustible tobacco (cigarettes and/or cigars). Three mutually exclusive categories of initiation patterns were evaluated: use of marijuana before tobacco; marijuana and tobacco at the same age; and tobacco before marijuana. Multivariable regression models were used to assess changes over time and compare these outcomes by race while controlling for sociodemographics, risk perceptions, and current substance use. In 2005, 26.6% of African American and 14.3% of white young adults used marijuana before tobacco, compared with 41.5% of African American and 24.0% of white young adults in 2012 (P < .001). Overall, African American young adults had greater odds of using marijuana before tobacco (AOR = 1.79; 95% CI: 1.67, 1.91) compared with whites. African American young adults were more likely than whites to use marijuana before tobacco and both groups were increasingly likely to use marijuana before tobacco over time. A greater understanding of how marijuana initiation interacts with tobacco initiation could inform more effective tobacco and marijuana use prevention efforts. Among ever users of combustible tobacco and marijuana, greater proportions of African American young adults used marijuana before tobacco or at the same age than their white counterparts. Moreover, both African Americans and whites were more likely to use marijuana before tobacco in 2012 compared with 2005. Tobacco

Effects of smoking marijuana on brain perfusion and cognition.

PubMed

O'Leary, Daniel S; Block, Robert I; Koeppel, Julie A; Flaum, Michael; Schultz, Susan K; Andreasen, Nancy C; Ponto, Laura Boles; Watkins, G Leonard; Hurtig, Richard R; Hichwa, Richard D

2002-06-01

The effects of smoking marijuana on regional cerebral blood flow (rCBF) and cognitive performance were assessed in 12 recreational users in a double-blinded, placebo-controlled study. PET with [(15)Oxygen]-labeled water ([(15)O]H(2)O) was used to measure rCBF before and after smoking of marijuana and placebo cigarettes, as subjects repeatedly performed an auditory attention task. Smoking marijuana resulted in intoxication, as assessed by a behavioral rating scale, but did not significantly alter mean behavioral performance on the attention task. Heart rate and blood pressure increased dramatically following smoking of marijuana but not placebo cigarettes. However, mean global CBF did not change significantly. Increased rCBF was observed in orbital and mesial frontal lobes, insula, temporal poles, anterior cingulate, as well as in the cerebellum. The increases in rCBF in anterior brain regions were predominantly in "paralimbic" regions and may be related to marijuana's mood-related effects. Reduced rCBF was observed in temporal lobe auditory regions, in visual cortex, and in brain regions that may be part of an attentional network (parietal lobe, frontal lobe and thalamus). These rCBF decreases may be the neural basis of perceptual and cognitive alterations that occur with acute marijuana intoxication. There was no significant rCBF change in the nucleus accumbens or other reward-related brain regions, nor in basal ganglia or hippocampus, which have a high density of cannabinoid receptors.

The Changing Drug Culture: Medical and Recreational Marijuana.

PubMed

Albertson, Timothy E; Chenoweth, James A; Colby, Daniel K; Sutter, Mark E

2016-02-01

The major psychoactive compounds in marijuana (cannabis) are cannabinoids, the most significant of which is delta-9-tetrahydrocannabinol. There are also two synthetic pharmaceutical cannabinoids, nabilone and dronabinol, available by prescription in the United States. The use of marijuana has increased in the United States with passage of medical marijuana laws in many states and legalization of recreational marijuana use in several states. In addition, the potency of marijuana has increased in recent years. Marijuana has been used for a variety of medical purposes, including management of nausea and vomiting, appetite and immunologic stimulation in patients with HIV infection and AIDS, glaucoma, neurologic disorders, and pain relief. Studies on the benefits of marijuana as a treatment for various conditions have been inconsistent, except for those on pain management. Marijuana has adverse effects, and has been associated with driving impairment, psychosis, dependence and withdrawal syndromes, hyperemesis, acute cardiac events, some cancers, and impaired lung function. As with studies on the benefits of marijuana, studies of adverse effects have yielded inconsistent results. Except for impaired driving and the occurrence of dependence and withdrawal syndromes, the adverse effects of marijuana use have not been fully studied. Written permission from the American Academy of Family Physicians is required for reproduction of this material in whole or in part in any form or medium.

Marijuana: modern medical chimaera.

PubMed

Lamarine, Roland J

2012-01-01

Marijuana has been used medically since antiquity. In recent years there has been a resurgence of interest in medical applications of various cannabis preparations. These drugs have been cited in the medical literature as potential secondary treatment agents for severe pain, muscle spasticity, anorexia, nausea, sleep disturbances, and numerous other uses. This article reviews the research literature related to medical applications of various forms of cannabis. Benefits related to medical use of cannabinoids are examined and a number of potential risks associated with cannabis use, both medical and recreational, are considered. There is a clearly identified need for further research to isolate significant benefits from the medical application of cannabinoids and to establish dosage levels, appropriate delivery mechanisms and formulations, and to determine what role, if any, cannabinoids might play in legitimate medical applications. It is also imperative to determine if reported dangers pose a significant health risks to users.

Medical marijuana.

PubMed Central

Marmor, J B

1998-01-01

Although many clinical studies suggest the medical utility of marijuana for some conditions, the scientific evidence is weak. Many patients in California are self-medicating with marijuana, and physicians need data to assess the risks and benefits. The only reasonable solution to this problem is to encourage research on the medical effects of marijuana. The current regulatory system should be modified to remove barriers to clinical research with marijuana. The NIH panel has identified several conditions for which there may be therapeutic benefit from marijuana use and that merit further research. Marijuana should be held to the same evaluation standards of safety and efficacy as other drugs (a major flaw in Proposition 215) but should not have to be proved better than current medications for its use to be adopted. The therapeutic window for marijuana and THC between desired effect and unpleasant side effects is narrow and is a major reason for discontinuing use. Although the inhaled route of administration has the benefit of allowing patients to self-titrate the dose, the smoking of crude plant material is problematic. The NIH panel recommended that a high priority be given to the development of a controlled inhaled form of THC. The presence of a naturally occurring cannabinoid-receptor system in the brain suggests that research on selective analogues of THC may be useful to enhance its therapeutic effects and minimize adverse effects. PMID:9656007

Medical marijuana laws and suicides by gender and age.

PubMed

Anderson, D Mark; Rees, Daniel I; Sabia, Joseph J

2014-12-01

We estimated the association between legalizing medical marijuana and suicides. We obtained state-level suicide data from the National Vital Statistics System's Mortality Detail Files for 1990-2007. We used regression analysis to examine the association between medical marijuana legalization and suicides per 100 000 population. After adjustment for economic conditions, state policies, and state-specific linear time trends, the association between legalizing medical marijuana and suicides was not statistically significant at the .05 level. However, legalization was associated with a 10.8% (95% confidence interval [CI] = -17.1%, -3.7%) and 9.4% (95% CI = -16.1%, -2.4%) reduction in the suicide rate of men aged 20 through 29 years and 30 through 39 years, respectively. Estimates for females were less precise and sensitive to model specification. Suicides among men aged 20 through 39 years fell after medical marijuana legalization compared with those in states that did not legalize. The negative relationship between legalization and suicides among young men is consistent with the hypothesis that marijuana can be used to cope with stressful life events. However, this relationship may be explained by alcohol consumption. The mechanism through which legalizing medical marijuana reduces suicides among young men remains a topic for future study.

Marijuana Use and Maternal Experiences of Severe Nausea During Pregnancy in Hawai‘i

PubMed Central

Patrick, Walter K; Hurwitz, Eric L

2014-01-01

Recreational use of marijuana is relatively common in the United States, and medicinal use is gaining popular and legal support. Marijuana has been proposed as a potential treatment for hyperemesis gravidarum. Research into this topic is complicated by associations between marijuana use and poor birth outcomes. Cannabinoid hyperemesis syndrome, which can cause severe nausea and vomiting in marijuana users, is another complicating factor. Hawai‘i Pregnancy Risk Assessment Monitoring System data from 4,735 respondents were used to estimate prevalence of self-reported marijuana use during and in the month before pregnancy, as well as severe nausea during pregnancy. Data were weighted to be representative of all pregnancies resulting in live births in Hawai‘i between 2009 and 2011. Prevalence ratios (PR) and 95% confidence intervals (CI) were computed to estimate associations. Of recently-pregnant women in Hawai‘i, 6.0% reported using marijuana in the month before pregnancy, and 2.6% reported using marijuana during pregnancy. Approximately 21.2% reported severe nausea during pregnancy. Women who reported severe nausea during pregnancy were significantly more likely to report marijuana use during pregnancy (3.7% vs 2.3%; PR=1.63, 95% CI: 1.08–2.44). More research is needed to investigate the relationship between marijuana use and severe nausea during pregnancy, and to quantify associated risks to mother and fetus. PMID:25285255

Marijuana use and maternal experiences of severe nausea during pregnancy in Hawai'i.

PubMed

Roberson, Emily K; Patrick, Walter K; Hurwitz, Eric L

2014-09-01

Recreational use of marijuana is relatively common in the United States, and medicinal use is gaining popular and legal support. Marijuana has been proposed as a potential treatment for hyperemesis gravidarum. Research into this topic is complicated by associations between marijuana use and poor birth outcomes. Cannabinoid hyperemesis syndrome, which can cause severe nausea and vomiting in marijuana users, is another complicating factor. Hawai'i Pregnancy Risk Assessment Monitoring System data from 4,735 respondents were used to estimate prevalence of self-reported marijuana use during and in the month before pregnancy, as well as severe nausea during pregnancy. Data were weighted to be representative of all pregnancies resulting in live births in Hawai'i between 2009 and 2011. Prevalence ratios (PR) and 95% confidence intervals (CI) were computed to estimate associations. Of recently-pregnant women in Hawai'i, 6.0% reported using marijuana in the month before pregnancy, and 2.6% reported using marijuana during pregnancy. Approximately 21.2% reported severe nausea during pregnancy. Women who reported severe nausea during pregnancy were significantly more likely to report marijuana use during pregnancy (3.7% vs 2.3%; PR=1.63, 95% CI: 1.08-2.44). More research is needed to investigate the relationship between marijuana use and severe nausea during pregnancy, and to quantify associated risks to mother and fetus.

LACTIC ACIDOSIS: A RARE MANIFESTATION OF SYNTHETIC MARIJUANA INTOXICATION.

PubMed

Antill, T; Jakkoju, A; Dieguez, J; Laskhmiprasad, L

2015-01-01

Synthetic cannabinoids are designer drugs that mimic the effect of cannabis, which has become popular with young drug users. These drugs have a similar chemical structure and pharmacologic effects as marijuana, but seem to be more potent. These substances have been banned by the US Drug Enforcement Agency in 2010. Prior to 2010, these drugs were perceived as "safer" by the general population. Synthetic cannabinoids cause effects similar to marijuana making the subjects euphoric. However, they act as full, rather than partial, agonist at the receptor sites causing more severe side effects such as severe agitation, seizures, acute renal failure, and lactic acidosis.

Medical marijuana for cancer.

PubMed

Kramer, Joan L

2015-03-01

Answer questions and earn CME/CNE Marijuana has been used for centuries, and interest in its medicinal properties has been increasing in recent years. Investigations into these medicinal properties has led to the development of cannabinoid pharmaceuticals such as dronabinol, nabilone, and nabiximols. Dronabinol is best studied in the treatment of nausea secondary to cancer chemotherapy and anorexia associated with weight loss in patients with acquired immune deficiency syndrome, and is approved by the US Food and Drug Administration for those indications. Nabilone has been best studied for the treatment of nausea secondary to cancer chemotherapy. There are also limited studies of these drugs for other conditions. Nabiximols is only available in the United States through clinical trials, but is used in Canada and the United Kingdom for the treatment of spasticity secondary to multiple sclerosis and pain. Studies of marijuana have concentrated on nausea, appetite, and pain. This article will review the literature regarding the medical use of marijuana and these cannabinoid pharmaceuticals (with emphasis on indications relevant to oncology), as well as available information regarding adverse effects of marijuana use. © 2014 American Cancer Society.