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The National Institutes of Health (NIH) support of cannabinoid and cannabis research has increased over the past few years. Several NIH Institutes, Centers, and Offices (ICOs) have a growing interest in the therapeutic potential of cannabis, cannabinoids, and related compounds as well as their adverse effects on health and society. The National Center on Complementary (NCCIH) and Integrative Health (NCCIH) has become a focal point for research on the therapeutic potential of the heretofore understudied minor cannabinoids and terpenes found in cannabis for the management of pain. Also, NCCIH has become more actively involved in coordinating activities to stimulate new research programs and coordinating various cannabis-related activities across the NIH. This presentation will provide an update on the broad landscape of cannabis-related research at the NIH, summarize new areas of research interest and investment, including those of NCCIH, and describe a new multi-NIH ICO extramural program coordinating group to foster collaboration, share information, and expand and coordinate NIH cannabis and cannabinoid research activities. [ABSTRACT FROM AUTHOR]

The prevalence of cannabis use disorders (CUDs) in people who use cannabis recreationally has been estimated at 22%, yet there is a dearth of literature exploring CUDs among people who use medicinal cannabis. We aimed to systematically review the prevalence of CUDs in people who use medicinal cannabis. In our systematic review and meta-analysis, we followed PRISMA guidelines and searched three databases (PsychInfo, Embase and PubMed) to identify studies examining the prevalence of CUDs in people who use medicinal cannabis. Meta-analyses were calculated on the prevalence of CUDs. Prevalence estimates were pooled across different prevalence periods using the DSM-IV and DSM-5. We conducted a systematic review of 14 eligible publications, assessing the prevalence of CUDs, providing data for 3681 participants from five different countries. The systematic review demonstrated that demographic factors, mental health disorders and the management of chronic pain with medicinal cannabis were associated with an elevated risk of CUDs. Meta-analyses were conducted on the prevalence of CUDs. For individuals using medicinal cannabis in the past 6–12 months, the prevalence of CUDs was 29% (95% CI: 21-38%) as per DSM-5 criteria. Similar prevalence was observed using DSM-IV (24%, CI: 14–38%) for the same period. When including all prevalence periods and using the DSM-5, the prevalence of CUDs in people who use medicinal cannabis was estimated at 25% (CI: 18-33%). The prevalence of CUDs in people who use medicinal cannabis is substantial and comparable to people who use cannabis for recreational reasons, emphasizing the need for ongoing research to monitor the prevalence of CUDs in people who use medicinal cannabis. • The prevalence of cannabis use disorders in people who use medicinal cannabis is estimated at 25% (CI: 18-33%). • People with chronic non-cancer pain, mental health or substance use disorders may have a higher risk of cannabis use disorder. • The study highlights the need to carefully consider the risk of cannabis use disorder when prescribing medicinal cannabis. [ABSTRACT FROM AUTHOR]

Cannabis use disorder (CUD) treatment prevalence decreased in the US between 2002 and 2019, yet structural mechanisms for this decrease are poorly understood. We tested associations between cannabis laws becoming effective and self-reported CUD treatment. Restricted-use 2004–2019 National Surveys on Drug Use and Health included people ages 12+ classified as needing CUD treatment (i.e., past-year DSM-5-proxy CUD or last/current specialty treatment for cannabis). Time-varying indicators of medical cannabis laws (MCL) with/without cannabis dispensary provisions differentiated state-years before/after laws using effective dates. Multi-level logistic regressions with random state intercepts estimated individual- and state-adjusted CUD treatment odds by MCLs and model-based changes in specialty CUD treatment state-level prevalence. Secondary analyses tested associations between CUD treatment and MCL or recreational cannabis laws (RCL). Using a broad treatment need sample definition in 2004–2014, specialty CUD treatment prevalence decreased by 1.35 (95 % CI = −2.51, −0.18) points after MCL without dispensaries and by 2.15 points (95 % CI = −3.29, −1.00) after MCL with dispensaries provisions became effective, compared to before MCL. Among people with CUD in 2004–2014, specialty treatment decreased only in MCL states with dispensary provisions (aPD = −0.91, 95 % CI = −1.68, −0.13). MCL were not associated with CUD treatment use in 2015–2019. RCL were associated with lower CUD treatment among people classified as needing CUD treatment, but not among people with past-year CUD. Policy-related reductions in specialty CUD treatment were concentrated in states with cannabis dispensary provisions in 2004–2014, but not 2015–2019, and partly driven by reductions among people without past-year CUD. Other mechanisms (e.g., CUD symptom identification, criminal-legal referrals) could contribute to decreasing treatment trends. • Specialty CUD treatment decreased in MCL states with dispensary provisions. • RCLs were associated with lower treatment among people needing CUD treatment. • Reductions were concentrated in 2004–2014, with lagged associations in 2015–2019. • CUD treatment remained low across the United States in 2004–2019. [ABSTRACT FROM AUTHOR]

Introduction: Young adults have the highest rates of cannabis and other drug use, as compared to other age groups, and contribute a significant proportion to the total population of medical cannabis patients (MCP). However, little is known about the relationships between various cannabis practices and illicit drug use/prescription drug misuse among young adult cannabis users with and without legal access to medical cannabis.Methods: 210 MCP and 156 non-patient cannabis users (NPU) aged 18-26 were recruited in Los Angeles in 2014-15 for a longitudinal study assessing the impact of medical cannabis on health and substance use among emerging adults. For the present analysis, only quantitative baseline survey data were used. Logistic regression was used to examine the associations between past 90-day cannabis practices and other drug use, including illicit drug use and prescription drug misuse.Results: Illicit drug use was associated with being non-Hispanic white (AOR = 3.0, 95% CI 1.8-5.1), use of cannabis concentrates (AOR = 2.8, 95% CI 1.6-4.9), while self-reported medical cannabis use was associated with lower probability of illicit drug use (AOR = 0.5, 95% CI 0.3-0.9). The odds of prescription drug misuse were increased for participants who reported use of cannabis edibles (AOR = 2.0, 95% CI 1.1-3.5), and decreased with age (AOR = 0.9, 95% CI 0.8-1.0) and for those who used cannabis alone (AOR = 0.5, 95% CI 0.3-0.9).Conclusion: Use of alternative cannabis forms, but not cannabis use frequency, were associated with greater odds of other drug use. Self-reported medical cannabis use, but not MCP status, decreased probability of illicit drug use. [ABSTRACT FROM AUTHOR]

Background: Driving under the influence of cannabis (DUIC) is a public health concern among those using medical cannabis. Understanding behaviors contributing to DUIC can inform prevention efforts. We evaluated three past 6-month DUIC behaviors among medical cannabis users with chronic pain.Methods: Adults (N = 790) seeking medical cannabis certification or recertification for moderate/severe pain were recruited from February 2014 through June 2015 at Michigan medical cannabis clinics. About half of participants were male (52%) and 81% were White; their Mean age was 45.8 years. Participants completed survey measures of DUIC (driving within 2 h of use, driving while "a little high," and driving while "very high") and background factors (demographics, alcohol use, etc.). Unadjusted and adjusted logistic regressions were used to examine correlates of DUIC.Results: For the past 6 months, DUIC within 2 h of use was reported by 56.4% of the sample, DUIC while a "little high" was reported by 50.5%, and "very high" was reported by 21.1%. Greater cannabis quantity consumed and binge drinking were generally associated with DUIC behaviors. Higher pain was associated with lower likelihood of DUIC. Findings vary somewhat across DUIC measures.Conclusions: The prevalence of DUIC is concerning, with more research needed on how to best measure DUIC. Prevention messaging for DUIC may be enhanced by addressing alcohol co-consumption. [ABSTRACT FROM AUTHOR]

Purpose: To describe patterns of cannabis withdrawal among a large sample of those who use medical cannabis and test the association between withdrawal symptomology and functioning.Procedures: Adults ages 21 and older (N = 801) who were seeking medical cannabis certification (either for the first time or as a renewal) for chronic pain at medical cannabis clinics in southern Michigan completed baseline measures of cannabis use, withdrawal symptomology, functioning and other related constructs. Patients were included in the current study if they endorsed using cannabis at least weekly over the past three months. Of the persons in the baseline sample (N = 801), 83% endorsed using cannabis at this level of frequency and duration (N = 665).Findings: Approximately two-thirds of the sample (67.8%) reported at least one moderate or severe withdrawal symptom. The most commonly observed symptom was sleep difficulties (50.3%), followed by anxiety (27.8%), irritability (26.7%), and appetite disturbance (25.2%). Patients with low mental functioning had significantly higher rates of withdrawal symptom endorsement than patients with high mental functioning. However, no association was observed between physical functioning and withdrawal symptom endorsement. These patterns of association were consistent in multivariate analyses that controlled for other potentially confounding variables.Conclusions: Cannabis withdrawal symptomology is highly prevalent among patients who use medical cannabis at least three times a week. Helping patients recognize the association between poorer functioning and withdrawal may be an effective way to highlight potentially negative consequences of regular and moderate heavy use. [ABSTRACT FROM AUTHOR]

Background: This study compared young adults with and without a medical marijuana (MM) recommendation from a provider ("MM card") on their developmental trajectories of frequent marijuana use and marijuana-related problems in young adulthood.Methods: The analytic sample consists of young adult past month marijuana users (N = 671) who were part of a larger, diverse, and predominantly California cohort. Analyses are based on data from seven surveys completed from ages 13-19.Results: At age 19, 28% of participants reported having an MM card to legally purchase marijuana from an MM dispensary. A multiple group latent growth model indicated that young adults who had an MM card showed steeper increases in frequent marijuana use (i.e., 20-30 days of use in the past month) from ages 13-19 compared to young adults who did not have an MM card. Logistic regression models that matched MM cardholders and non-MM cardholders on individual sociodemographic characteristics found that MM cardholders were more likely to report marijuana negative consequences, selling marijuana/hashish, and driving under the influence of marijuana in the past year. In addition, MM cardholders were more likely to have tried cutting down or quitting in the past 3-months.Conclusions: Among young adult marijuana users, those with an MM card had a higher risk profile for marijuana use and related problems compared to those without an MM card. Given expanding state legalization of MM, this issue warrants further attention. [ABSTRACT FROM AUTHOR]

Objectives: Medical marijuana use may substitute prescription opioid use, whereas nonmedical marijuana use may be a risk factor of prescription opioid misuse. This study examined the associations between recreational marijuana legalization and prescription opioids received by Medicaid enrollees.Methods: State-level quarterly prescription drug utilization records for Medicaid enrollees during 2010-2017 were obtained from Medicaid State Drug Utilization Data. The primary outcome, opioid prescriptions received, was measured in three population-adjusted variables: number of opioid prescriptions, total doses of opioid prescriptions in morphine milligram equivalents, and related Medicaid spending, per quarter per 100 enrollees. Two difference-in-difference models were used to test the associations: eight states and DC that legalized recreational marijuana during the study period were first compared among themselves, then compared to six states with medical marijuana legalized before the study period. Schedule II and III opioids were analyzed separately.Results: In models comparing eight states and DC, legalization was not associated with Schedule II opioid outcomes; having recreational marijuana legalization effective in 2015 was associated with reductions in number of prescriptions, total doses, and spending of Schedule III opioids by 32% (95% CI: (-49%, -15%), p = 0.003), 30% ((-55%, -4.4%), p = 0.027), and 31% ((-59%, -3.6%), p = 0.031), respectively. In models comparing eight states and DC to six states with medical marijuana legalization, recreational marijuana legalization was not associated with any opioid outcome.Conclusions: No evidence suggested that recreational marijuana legalization increased prescription opioids received by Medicaid enrollees. There was some evidence in some states for reduced Schedule III opioids following the legalization. [ABSTRACT FROM AUTHOR]

Background: Both cannabis use and alcohol use are elevated among people living with HIV, but few studies have investigated the relationship between cannabis use and alcohol use in this population. This study examined the longitudinal association between cannabis use and alcohol use among people living with HIV and explored the moderating role of medicinal vs. recreational cannabis use.Method: Participants were cannabis users (N=763) enrolled in the Ontario HIV Treatment Network Cohort Study (67% White, 88% male, 68% gay, median income in the $40,000-$50,000 range). Participants completed assessments of cannabis use, reasons for cannabis use, and alcohol use at baseline and at annual follow-ups (M = 3.42 completed assessments). Multilevel modeling was used to examine between-person and within-person associations between cannabis use and alcohol use over time.Results: Greater average frequency of cannabis use was associated with greater average alcohol consumption across participants. Participants classified as medicinal cannabis users reported more frequent cannabis use and less alcohol use on average than recreational cannabis users. Further, within-person changes in cannabis use over time were positively associated with corresponding changes in alcohol use for recreational cannabis users but not for medicinal users.Conclusion: Cannabis use and alcohol use were positively associated over time among people living with HIV, although this association was specific to those using cannabis for recreational reasons. As alcohol use in this population poses significant health risks, more research on the link between cannabis use and alcohol use is needed, particularly in light of recent changes to cannabis regulations. [ABSTRACT FROM AUTHOR]

Background: It is common for cannabis users to also use tobacco. While data suggest that tobacco users have more difficulty achieving cannabis cessation, secondary analyses of clinical trial data sets may provide insight into the moderating variables contributing to this relationship, as well as changes in tobacco use during cannabis treatment. Those were the aims of this secondary analysis.Methods: The parent study was a multi-site trial of N-acetylcysteine for cannabis dependence conducted within the National Drug Abuse Treatment Clinical Trials Network. Participants were treatment-seeking adults (ages 18-50) who met criteria for cannabis dependence (N = 302). For cigarette smokers (n = 117), tobacco use was assessed via timeline follow-back and nicotine dependence was assessed via the Fagerström Test for Nicotine Dependence (FTND). Outcome measures included: 1) changes in tobacco use based on treatment assignment, nicotine dependence, and concurrent cannabis reduction/abstinence, and 2) independent associations between nicotine dependence and cannabis abstinence.Results: Cigarette smokers accounted for 39% of the sample (117/302), with a median FTND score of 3.0 (10-point scale). Among those with lower baseline nicotine dependence scores, cigarette smoking was reduced in the active treatment group compared to placebo. Those with moderate/high levels of nicotine dependence showed slight increases in smoking following active treatment. Nicotine dependence did not affect cannabis cessation.Conclusions: Cigarette smoking during cannabis treatment was affected, but depended on baseline nicotine dependence severity, though dependence levels did not impact cannabis abstinence. Interventions that address both tobacco and cannabis are needed, especially due to an increasing prevalence of cannabis use. [ABSTRACT FROM AUTHOR]

Background: Previous research shows that between individuals there is a positive association between medically motivated use and cannabis use frequency and quantity. While between-subjects' analyses are useful for understanding shared vulnerabilities, research has so far not examined within-subjects' relationships which are closer to evaluating functional relationships (i.e., do individuals tend to use cannabis more heavily subsequent to elevations in pain experiences?). To better understand the association between experiences of pain and cannabis use, the current paper examines whether there is a functional within-subjects association between experiences of pain and heavy cannabis use.Methods: 182 regular cannabis users without a medical cannabis license were asked to report momentary experiences of physical pain, whether they had used cannabis, and if so, quantity consumed five times per day over a five-day period on their smartphones. Mixed effects models examined the relations between within- and between-subjects experiences of pain and cannabis use and quantity consumed.Results: Elevated experiences of pain were not associated with cannabis use occasions at the within- or between-subjects level. Experiences of pain were associated with greater amount of cannabis consumed at the within-subjects level, but not at the between-subjects level.Conclusions: Experiences of pain are not associated with decisions about whether or not to use cannabis. Once cannabis users are in cannabis-using situations, they tend to use larger amounts when they are experiencing elevated levels of pain. This may have implications for cannabis abuse treatment as pain may make it more difficult for users to reduce their consumption. [ABSTRACT FROM AUTHOR]

There is little research examining perceptions of cannabis use risk to mental health in countries with differing cannabis regulations. This study therefore examines such perceptions among youth between 2017 and 2021 in Canada (non-medical cannabis legalized in October 2018), England (highly-restricted medical cannabis legalized November 2018), and the US (non-medical cannabis legal in some states). Seven repeat cross-sectional online surveys were conducted between July 2017 to August 2021 among youth aged 16–19 in Canada (N=29,420), England (N=28,155), and the US (N=32,974). Logistic regression models, stratified by country, were used to examine perceptions of cannabis use risk to mental health over time, adjusting for age group, sex, race/ethnicity, cannabis use and, for the US only, state-level cannabis legalization. Perceptions that cannabis use posed "no risk" to mental health decreased between July 2017 and August 2021 in Canada (6.1–4.4%; AOR=0.64, 95% CI=0.52–0.78) and the US (14.0–11.3%; AOR=0.74, 0.65–0.84) but not England (3.7–4.5%; AOR=1.21, 0.97–1.52). No significant changes were observed from immediately before (August 2018) to after (August 2019) legalization of non-medical cannabis in Canada (AOR=0.99, 0.83–1.20) or highly-restricted medical cannabis in England (AOR=0.90, 0.70–1.17). In the US, perceptions of "no risk" were more likely in states where cannabis use was illegal (15.0%) compared with legal non-medical (12.2%) (AOR=0.68, 0.63–0.74). There were modest decreases in perceptions that cannabis use poses no risk to mental health in Canada and the US between 2017 and 2021 but no clear association with cannabis legalization status. • Trends in youth's perceptions of cannabis use risk to mental health were explored. • Data were from three countries with differing cannabis policies: Canada, England, US. • 89,158 youth aged 16–19 years were surveyed between 2017 and 2021. • Perceptions that cannabis posed no risk to mental health decreased in Canada and US. • There was no clear association between risk perceptions and legalization status. [ABSTRACT FROM AUTHOR]

Background: 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.Methods: 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.Results: 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.Conclusions: 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. [ABSTRACT FROM AUTHOR]

Background: The agreement between self-reported cannabis abstinence with urine cannabinoid concentrations in a clinical trials setting is not well characterized. We assessed the agreement between various cannabinoid cutoffs and self-reported abstinence across three clinical trials, one including contingency management for abstinence.Methods: Three cannabis cessation clinical trials where participants reported use and provided weekly urine samples for cannabis and creatinine concentration measurements were included. Bootstrapped data were assessed for agreement between self-reported 7+ day abstinence and urine cannabinoid tests using generalized linear mixed effects models for clustered binary outcomes. One study implemented contingency management for cannabis abstinence. Four hundred and seventy-three participants with 3787 valid urine specimens were included. Urine was analyzed for 11-nor-9-carboxy-Δ9-tetrahydrocannabinol and creatinine using immunoassay methods Biological cutoffs of 50, 100, and 200 ng/ml, as well as changes in CN normalized THCCOOH (25%/50% decrease), were assessed for agreement with self-reported abstinence during the three clinical trials.Results: Agreement between measured THCCOOH and self-reported abstinence increases with increasing cutoff concentrations, while the agreement with self-reported non-abstinence decreases with increasing cutoff concentrations. Combining THCCOOH cutoffs with recent changes in CN-THCCOOH provides a better agreement in those self-reporting abstinence. Participants in the studies that received CM for abstinence had a lower agreement between self-reported abstinence and returned to use than those in studies that did not have a contingency management component.Conclusion: Using combinations of biological measurements and self-reported abstinence, confirmation of study related abstinence may be verifiable earlier and with greater accuracy than relying on a single measurement. [ABSTRACT FROM AUTHOR]

Background: Self-medication with drugs or alcohol is commonly reported among adults with mood or anxiety disorders, and increases the risk of developing substance use disorders. Medical marijuana laws (MML) may be associated with greater acceptance of the therapeutic value of marijuana, leading individuals to self-medicate.Methods: The study utilized data from Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (2004-2005). Participants were sampled from households in the general population and included adults with a mood or anxiety disorder in the past 12 months (n = 7418), and the subset of those who used marijuana and no other drug (n = 314). Weighted logistic regression models predicted the prevalence of self-medication with drugs in U.S. states with and without MML, adjusting for individual and state-level covariates. As a negative control, analyses were repeated for self-medication with alcohol.Results: Overall, self-medication with drugs was 3.73 percentage points higher (95% confidence interval [CI]: 0.93-6.53) among those living in MML states (p = 0.01). For the subpopulation that only used marijuana, self-medication with drugs was 21.22 percentage points higher (95% CI: 3.91-38.53) among those living in MML states (p = 0.02). In contrast, self-medication with alcohol had nearly identical prevalence in MML and non-MML states, overall and for drinkers.Conclusions: Among adults with mood or anxiety disorders, living in a medical marijuana law state is associated with self-medication with marijuana. While additional research is needed to determine the reasons for this association, clinical screening for self-medication with marijuana may be particularly important in states with medical marijuana laws. [ABSTRACT FROM AUTHOR]

Background: This experimental study tests effects of exposure to video narratives about successful symptom relief with Medical Cannabis (MC) on attitudes, beliefs, and intentions related to recreational cannabis use.Methods: Patient video testimonials were modeled after those found in extant media coverage. Israeli participants (N = 396) recruited through an online survey company were randomly assigned to view a narrative or a non-narrative video containing equivalent information about MC. Video content was further manipulated based on whether the protagonist had a stigmatized disease or not, and whether attribution of responsibility for his disease was internal or external.Results: Exposure to patient testimonials indirectly increased positive attitudes, beliefs and intentions related to recreational cannabis use through changing attitudes, beliefs and intentions related to MC. Furthermore, exposure to narratives in which the patient was presented as not to blame for contracting his illness (external attribution) was associated with more positive attitudes, beliefs and intentions toward MC, a factor that was significantly associated with more positive attitudes, beliefs and intentions related to recreational cannabis use.Conclusions: These results suggest that narrative news media coverage of MC may influence public attitudes toward recreational cannabis. Because such media stories continue to be commonplace, it is important to examine potential spillover effects of this coverage on public perceptions of recreational cannabis. Cannabis prevention programs should address the role of media coverage in shaping public opinion and address the distinction between medical and recreational cannabis use. [ABSTRACT FROM AUTHOR]

Objective: To examine if a substance use disorder (SUD), especially cannabis use disorder in adolescence, predicts future medical cannabis card status among high-risk youth.Methods: Data collection occurred in Denver and San Diego. We recruited adolescents, with or at high risk for SUD and conduct problems (hereafter probands) and their siblings (n=654). Baseline (Wave 1) assessments took place between 1999 and 2008, and follow-up (Wave 2) took place between 2010 and 2013. In initial bivariate analyses, we examined whether baseline DSM-IV cannabis abuse/dependence (along with other potential predictors) was associated with possessing a medical cannabis card in young adulthood (Wave 2). Significant predictors were then included in a multiple binomial regression. Self-reported general physical health was also evaluated at both time points. Finally, within Wave 2, we tested whether card status was associated with concurrent substance dependence.Results: About 16% of the sample self-reported having a medical cannabis card at follow-up. Though bivariate analyses demonstrated that multiple predictors were significantly associated with Wave 2 card status, in our multiple binomial regression only cannabis abuse/dependence and male sex remained significant. At Wave 2, those with a medical cannabis card were significantly more likely to endorse criteria for concurrent cannabis dependence. There was no significant difference in self-reported general physical health.Conclusions: Cannabis abuse/dependence and male sex positively predicted future medical cannabis card holder status among a sample of high risk adolescents. Physicians conducting evaluations for medical cannabis cards should carefully evaluate and consider past and concurrent cannabis addiction. [ABSTRACT FROM AUTHOR]

Background: Historical shifts have taken place in the last twenty years in marijuana policy. The impact of medical marijuana laws (MML) on use of substances other than marijuana is not well understood. We examined the relationship between state MML and use of marijuana, cigarettes, illicit drugs, nonmedical use of prescription opioids, amphetamines, and tranquilizers, as well as binge drinking.Methods: Pre-post MML difference-in-difference analyses were performed on a nationally representative sample of adolescents in 48 contiguous U.S. states. Participants were 1,179,372U.S. 8th, 10th, and 12th graders in the national Monitoring the Future annual surveys conducted in 1991-2015. Measurements were any self-reported past-30-day use of marijuana, cigarettes, non-medical use of opioids, amphetamines and tranquilizers, other illicit substances, and any past-two-week binge drinking (5+ drinks per occasion).Results: Among 8th graders, the prevalence of marijuana, binge drinking, cigarette use, non-medical use of opioids, amphetamines and tranquilizers, and any non-marijuana illicit drug use decreased after MML enactment (0.2-2.4% decrease; p-values:<0.0001-0.0293). Among 10th graders, the prevalence of substance use did not change after MML enactment (p-values: 0.177-0.938). Among 12th graders, non-medical prescription opioid and cigarette use increased after MML enactment (0.9-2.7% increase; p-values: <0.0001-0.0026).Conclusions: MML enactment is associated with decreases in marijuana and other drugs in early adolescence in those states. Mechanisms that explain the increase in non-medical prescription opioid and cigarette use among 12th graders following MML enactment deserve further study. [ABSTRACT FROM AUTHOR]

Purpose: To examine the prevalence and correlates of sleep problems in a sample of medical cannabis patients.Procedures: Adults ages 21 and older (N=801,M age=45.8) who were seeking medical cannabis certification (either for the first time or as a renewal) for chronic pain at medical cannabis clinics in southern Michigan completed baseline measures of cannabis use, sleep, pain, and other related constructs.Findings: Over half of the sample (59%) met criteria for past 1-month sleep disturbance, defined as at least one sleep problem occurring on 15 or more nights in the past month. Most participants (86%) reported that sleep problems were due to their current pain. Approximately 80% of participants reported using cannabis in the past 6 months to improve sleep and, among these participants, cannabis was rated as helpful for improving sleep. Sleep-related cannabis side effects were rare (35%), but sleep-related cannabis withdrawal symptoms were relatively common (65%). Statistically significant correlates of past 1-month sleep disturbance included a) being female, b) being white, c) being on disability, d) not having a medical cannabis card, and e) frequency of using cannabis to help sleep.Conclusions: Sleep problems are highly prevalent and frequent in medical cannabis patients and are closely tied to pain. Sleep-related cannabis withdrawal symptoms are relatively common but their clinical relevance is unknown. The association between frequency of cannabis use to help sleep with higher odds of sleep problems will need to be clarified by longitudinal studies. [ABSTRACT FROM AUTHOR]

Background: While medical marijuana use is legal in more than half of U.S. states, evidence is limited about the preparation of physicians-in-training to prescribe medical marijuana. We asked whether current medical school and graduate medical educational training prepare physicians to prescribe medical marijuana.Methods: We conducted a national survey of U.S. medical school curriculum deans, a similar survey of residents and fellows at Washington University in St. Louis, and a query of the Association of American Medical Colleges (AAMC) Curriculum Inventory database for keywords associated with medical marijuana.Results: Surveys were obtained from 101 curriculum deans, and 258 residents and fellows. 145 schools were included in the curriculum search. The majority of deans (66.7%) reported that their graduates were not at all prepared to prescribe medical marijuana, and 25.0% reported that their graduates were not at all prepared to answer questions about medical marijuana. The vast majority of residents and fellows (89.5%) felt not at all prepared to prescribe medical marijuana, while 35.3% felt not at all prepared to answer questions, and 84.9% reported receiving no education in medical school or residency on medical marijuana. Finally, only 9% of medical school curriculums document in the AAMC Curriculum Inventory database content on medical marijuana.Conclusions: Our study highlights a fundamental mismatch between the state-level legalization of medical marijuana and the lack of preparation of physicians-in-training to prescribe it. With even more states on the cusp of legalizing medical marijuana, physician training should adapt to encompass this new reality of medical practice. [ABSTRACT FROM AUTHOR]

Few studies examine the utility of the Cannabis Use Disorder Identification Test – Revised (CUDIT-R) in relation to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, (DSM-5) criteria for cannabis use disorder (CUD). This study assesses the performance of the CUDIT-R among a sample of Veterans with and without medical cannabis use. We approached and consented primary care patients presenting to one of three Department of Veterans Affairs (VA) Medical Centers. Veterans with at least monthly cannabis use and complete CUD data at baseline were included in this analysis (n=234). CUDIT-R scores were compared against Alcohol Use Disorder and Associated Disabilities Interview Schedule-5 (DSM-5) CUD as the standard to calculate measures of validity (sensitivity, specificity), identify optimal CUDIT-R cutoff values, and assess the diagnostic proficiency of the CUDIT-R using receiver operating characteristic (ROC) curves. We further stratified analyses by active medical cannabis card holder status and DSM-5 CUD severity (any, moderate, and severe). Among the entire sample, 38.9% qualified for any DSM-5 CUD, with 10.7% and 3.0% meeting criteria for moderate and severe CUD, respectively. We identified optimal CUDIT-R scores at 10 for any DSM-5 CUD (sensitivity=0.58; specificity=0.80), at 12 for moderate CUD (sensitivity=0.72; specificity=0.82), and at 14 for severe CUD (sensitivity=0.71; specificity=0.87). ROC curves showed higher CUDIT-R validity among non-card holders compared with medical cannabis card holders. The present study identified optimal CUDIT-R cutoff scores for Veterans who use cannabis. Varying DSM-5 validity measures inform the need for population-specific CUDIT-R cutoff values. • Among a sample of cannabis using Veterans, 38.9% reported any DSM-5 CUD. • We estimated an optimal CUDIT-R score of 10 to identify any CUD among the sample. • We estimated optimal CUDIT-R scores for moderate (12) and severe CUD (14). • Medical cannabis card holders showed greater CUDIT-R cutoff values than those without. • Estimated CUDIT-R validity was greatest among non-card holders. [ABSTRACT FROM AUTHOR]

Aims: The study seeks to characterize marijuana concentrate users, describe reasons and patterns of use, perceived risk, and identify predictors of daily/near daily use.Methods: 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.Results: 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).Conclusions: 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. [ABSTRACT FROM AUTHOR]

Background: The use of marijuana for medical purposes is now legal in some U.S. states and other jurisdictions, such as Canada, and Israel. Despite the widespread legalization of medical marijuana globally, there is limited information on patterns and correlates of medical marijuana use (MMU). We conducted a literature review to assess prevalence, reasons, perceived effects, and correlates of MMU among adolescents and adults.Methods: We searched peer-reviewed articles in English between January 1996 and August 2016 from several databases (PubMed, Google Scholar, Embase, CINAHL, and PsycINFO) using different combinations of keywords.Results: A total of 25 articles met the inclusion criteria. In the U.S., national survey estimates of prescribed MMU was 1.1% among 12th graders and 17% among adults who reported past-year marijuana use. The reported prevalence of prescribed MMU ranged from <1.7% in Israeli cancer patients to 17.4% in American health care patients. The reported prevalence of self-medication with marijuana ranged from 15% in Canadian patients with chronic pain to 30% in British patients with multiple sclerosis. Pain was the most frequently endorsed reason for use. MMU appeared to provide symptom relief for a range of pain conditions, sleep disturbance, and anxiety symptoms, but it did not appear to provide sufficient relief of cluster headache symptoms. Non-medical marijuana use was a common factor associated with MMU across studies.Conclusion: Either MMU or self-medication with marijuana was common, mainly due to pain management. Additional research is needed to evaluate temporal and causal associations of non-medical marijuana use with MMU. [ABSTRACT FROM AUTHOR]

Background: Cannabis use rates are increasing among adults in the United States (US) while the perception of harm is declining. This may result in an increased prevalence of cannabis use disorder and the need for more clinical trials to evaluate efficacious treatment strategies. Clinical trials are the gold standard for evaluating treatment, yet study samples are rarely representative of the target population. This finding has not yet been established for cannabis treatment trials. This study compared demographic and cannabis use characteristics of a cannabis cessation clinical trial sample (run through National Drug Abuse Treatment Clinical Trials Network) with three nationally representative datasets from the US; 1) National Survey on Drug Use and Health, 2) National Epidemiologic Survey on Alcohol and Related Conditions-III, and 3) Treatment: Episodes Data Set - Admissions.Methods: Comparisons were made between the clinical trial sample and appropriate cannabis using sub-samples from the national datasets, and propensity scores were calculated to determine the degree of similarity between samples.Results: showed that the clinical trial sample was significantly different from all three national datasets, with the clinical trial sample having greater representation among older adults, African Americans, Hispanic/Latinos, adults with more education, non-tobacco users, and daily and almost daily cannabis users.Conclusions: These results are consistent with previous studies of other substance use disorder populations and extend sample representation issues to a cannabis use disorder population. This illustrates the need to ensure representative samples within cannabis treatment clinical trials to improve the generalizability of promising findings. [ABSTRACT FROM AUTHOR]

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=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.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. [ABSTRACT FROM AUTHOR]

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 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.Results: 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.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. [ABSTRACT FROM AUTHOR]

Introduction: The use of cannabis or cannabinoids to treat medical conditions and/or alleviate symptoms is increasingly common. However, the impact of this use on patient reported outcomes, such as health-related quality of life (HRQoL), remains unclear.Methods: We conducted a systematic review and meta-analysis, employing guidelines from Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We categorized studies based on design, targeted disease condition, and type of cannabis or cannabinoid used. We scored studies based on quality and risk of bias. After eliminating some studies because of poor quality or insufficient data, we conducted meta-analyses of remaining studies based on design.Results: Twenty studies met our pre-defined selection criteria. Eleven studies were randomized controlled trials (RCTs; 2322 participants); the remaining studies were of cohort and cross-sectional design. Studies of cannabinoids were mostly RCTs of higher design quality than studies of cannabis, which utilized smaller self-selected samples in observational studies. Although we did not uncover a significant association between cannabis and cannabinoids for medical conditions and HRQoL, some patients who used them to treat pain, multiple sclerosis, and inflammatory bower disorders have reported small improvements in HRQoL, whereas some HIV patients have reported reduced HRQoL.Conclusion: The relationship between HRQoL and the use of cannabis or cannabinoids for medical conditions is inconclusive. Some patient populations report improvements whereas others report reductions in HRQoL. In order to inform users, practitioners, and policymakers more clearly, future studies should adhere to stricter research quality guidelines and more clearly report patient outcomes. [ABSTRACT FROM AUTHOR]

Objectives: To assess the association between U.S. state medical marijuana laws (MML), the most liberal category of marijuana policies before legalization, their specific provisions, and adolescent past-30-day use and heavy marijuana use.Methods: This quasi-experimental study used state Youth Risk Behavior Survey (YRBS) data collected during 1991-2011 from 45 states (N=715,014) to examine MML effects, taking advantage of heterogeneity across states in MML status and design. Multiple logistic regression modeling was used to adjust for state and year effects, and youth demographics.Results: Unadjusted analyses found that MMLs were associated with higher rates of adolescent past-30-day marijuana use (odds ratio [OR]=1.08, 95% confidence interval, [(CI)=1.03,1.13]) and heavy marijuana use (OR=1.12, [CI=1.05,1.21]). However, analyses adjusting for state/year effects found a 7% lower odds of use (OR=0.99, [CI=0.98,0.999]) and no difference in heavy use. In the adjusted models, years since MML enactment (OR=0.93, [CI=0.86,0.99]) and MML inclusion of more liberalized provisions (OR=0.98, [CI=0.96,0.998]) were associated with slightly lowered odds of past-30-day marijuana use. Conversely, allowance for ≥2.5 usable marijuana ounces was associated with higher past-30-day marijuana use odds (OR=1.21, [CI=1.09,1.34]) and a voluntary vs. mandatory patient registration with higher odds of both past-30-day use (OR=1.41, [CI=1.28,1.56]) and heavy use (OR=1.23, [CI=1.08,1.40]).Conclusions: MML enactment, years since enactment, and inclusion of more liberalized provisions were not associated with increased adolescent marijuana use in this dataset after adjusting for state and year effects; however, higher possession limits and a voluntary registration were. It is possible that state norms are the impetus for MML enactment. [ABSTRACT FROM AUTHOR]

Background: Little is known about young adult medical marijuana patients (MMP) and their marijuana using patterns and practices, which includes frequency of use, sourcing of marijuana products, forms/modes of administration, and patterns of illicit/prescription drug misuse, compared to non-patient marijuana users (NPU).Methods: Young adults (N=366) aged 18-26 years old were sampled in Los Angeles in 2014-15 and segmented into NPU (n=156), marijuana users who never had a medical marijuana (MM) recommendation, and MMP (n=210), marijuana users with a current, verified MM recommendation. Differences regarding self-reported marijuana and other drug use during the past 90days are expressed as unadjusted risk ratios or differences in means.Results: MMP reported significantly greater mean days of use (76.4 vs. 59.2, p<0.001) and mean dollars spent on marijuana products (564.5 vs. 266.9, p<0.001) than NPU. Approximately one-quarter (22.6%) of both MMP and NPU report selling marijuana obtained from a dispensary to someone else in the past 90days. MMP were more likely to report vaporization modalities for concentrates (URR=1.5, 95% C.I.=1.2, 2.0) and for marijuana (URR=1.5, 95% C.I.=1.1, 2.1) than NPU. Though not significant, trends toward lower misuse of prescription drugs in the past 90days were observed among MMP compared to NPU.Conclusion: MMP reported greater access to marijuana via dispensaries, more frequent and intensive use of marijuana, and greater use of non-combustible forms of marijuana compared to NPU. MMP reported less recent misuse of prescription drugs compared to NPU. [ABSTRACT FROM AUTHOR]

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 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.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. [ABSTRACT FROM AUTHOR]

Purpose: To examine the prevalence and correlates of vaporization (i.e., "vaping") as a route of cannabis administration in a sample of medical cannabis patients.Procedures: Adults ages 21 and older (N=1485M age=45.1) who were seeking medical cannabis certification (either for the first time or as a renewal) at medical cannabis clinics in southern Michigan completed a screening assessment. Participants completed measures of route of cannabis administration, cannabis use, alcohol and other substance use.Findings: An estimated 39% (n=511) of the sample reported past-month cannabis vaping, but vaping as the sole route of cannabis administration was rare. Specifically, only 30 participants (2.3% of the full sample and 5.9% of those who reported any vaping) indicated vaping as the sole route of cannabis administration. The majority (87.3%) of those who reported vaping also reported smoking (combustion) as a route of cannabis administration. Being younger than age 44, having more than a high school education, engaging in nonmedical stimulant use, being a returning medical cannabis patient, and greater frequency of cannabis use were associated with higher odds of vaping at the bivariate level and with all variables considered simultaneously.Conclusions: Vaping appears to be relatively common among medical cannabis patients, but is seldom used as the sole route of cannabis administration.Results: highlight the importance of monitoring trends in vaping and other substance use behaviors in this population and underscore the need for longitudinal research into the motives, correlates, and consequences of cannabis vaping in medical cannabis patients. [ABSTRACT FROM AUTHOR]

Background: Rates of young adult cannabis use are rising, perceived harm is at its historical nadir, and most users do not want to quit. Most studies evaluating effects of cannabis use in young adults are cross-sectional, limiting causal inference. A method to reliably induce abstinence periods in cannabis users would allow assessment of the effects of abstinence and resumption of use on a variety of outcomes in a within-subjects, repeated measures design.Methods: We examined the efficacy and feasibility of a voucher-based contingency management procedure for incentivizing one month of continuous cannabis abstinence among young adults who reported at least weekly cannabis use, volunteered to participate in a laboratory study, and did not express a desire to discontinue cannabis use long-term. Continuous cannabis abstinence was reinforced with an escalating incentive schedule, and self-report of abstinence was confirmed by frequent quantitative assays of urine cannabis metabolite (THCCOOH) concentration. New cannabis use during the abstinence period was determined using an established algorithm of change in creatinine-adjusted cannabis metabolite concentrations between study visits.Results: Thirty-eight young adults, aged 18-25 years, enrolled and 34 (89.5%) attained biochemically confirmed 30-day abstinence. Among those who attained abstinence, 93.9% resumed regular use within two-weeks of incentive discontinuation.Conclusion: Findings support the feasibility and efficacy of contingency management to elicit short-term, continuous cannabis abstinence among young adult, non-treatment seeking, regular cannabis users. Further work should test the effectiveness of this contingency management procedure for cannabis abstinence in periods longer than one month, which may be required to evaluate some effects of abstinence. [ABSTRACT FROM AUTHOR]

Objectives: To characterize the socio-demographic characteristics, medical conditions, and psychiatric comorbidities of users of marijuana for medical and non-medical purposes.Methods: Data were from the National Epidemiological Survey on Alcohol and Related Conditions III, a US nationally representative in-person interview of 36,309 adults age ≥18 years in 2012-2013.Results: In relation to non-medical only users (n = 3339), combined (n = 362) and medical only (n = 82) users had higher prevalence of every medical condition examined. As compared to the combined use group, those using marijuana only for medical purposes were much less likely to have anxiety, alcohol, or non-medical prescription opioid use disorders.Conclusions: Medical-only users appear to use it for evidence-based medical reasons and have lower prevalence of substance use disorder than other marijuana users. Nonetheless, because most medical marijuana users also use non-medically, screening for psychiatric disorders and prevention efforts for cannabis use disorder should be implemented when authorizing medical marijuana. [ABSTRACT FROM AUTHOR]

Background: The prevention of youth marijuana use has become a national priority in the United States. This study examined the influence of parent and peer disapproval on youth marijuana use, mediated by youth risk perception. Because the legal status of marijuana use can influence individual perceptions of the drug, this study investigated differences in the mediating mechanism between youth living in states with medical marijuana legalization (MML) and those living in non-MML states.Methods: The 2019 National Survey of Drug Use and Health was used with a youth population aged 12-17 years (N = 2293). Structural equation modeling and bias-corrected bootstrapping were used to examine hypothesized path models and to evaluate the mediating effect of youth risk perception.Result: Findings demonstrated that parent and peer disapproval significantly increased youth risk perception of marijuana and reduced youth marijuana use. Second, youth risk perception significantly mediated the association between parent and peer disapproval and youth marijuana use. Third, parent disapproval had a more significant direct effect on youth marijuana use, while peer disapproval had a more significant indirect effect on youth marijuana use via youth risk perception. Finally, the results showed a similar pattern in the mechanism between youths living in MML states compared with those in non-MML states in terms of significance and direction.Conclusion: The findings suggested a need for improvements in marijuana related policies for both MML and non-MML states. Moreover, parent and peer focused strategies for education and prevention concerning marijuana use among youth are emphasized. [ABSTRACT FROM AUTHOR]

Background: 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.Methods: 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.Results: 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).Conclusion: Marijuana policy could inadvertently affect cigarette and marijuana co-use and pose challenges to tobacco cessation. [ABSTRACT FROM AUTHOR]

Background: Both Attention Deficit Hyperactivity Disorder (ADHD) and chronic cannabis (CAN) use have been associated with brain structural abnormalities, although little is known about the effects of both in young adults.Methods: Participants included: those with a childhood diagnosis of ADHD who were CAN users (ADHD_CAN; n=37) and non-users (NU) (ADHD_NU; n=44) and a local normative comparison group (LNCG) who did (LNCG_CAN; n=18) and did not (LNCG_NU; n=21) use CAN regularly. Multiple regressions and MANCOVAs were used to examine the independent and interactive effects of a childhood ADHD diagnosis and CAN group status and age of onset (CUO) on subcortical volumes and cortical thickness.Results: After controlling for age, gender, total brain volume, nicotine use, and past-year binge drinking, childhood ADHD diagnosis did not predict brain structure; however, persistence of ADHD was associated with smaller left precentral/postcentral cortical thickness. Compared to all non-users, CAN users had decreased cortical thickness in right hemisphere superior frontal sulcus, anterior cingulate, and isthmus of cingulate gyrus regions and left hemisphere superior frontal sulcus and precentral gyrus regions. Early cannabis use age of onset (CUO) in those with ADHD predicted greater right hemisphere superior frontal and postcentral cortical thickness.Discussion: Young adults with persistent ADHD demonstrated brain structure abnormalities in regions underlying motor control, working memory and inhibitory control. Further, CAN use was linked with abnormal brain structure in regions with high concentrations of cannabinoid receptors. Additional large-scale longitudinal studies are needed to clarify how substance use impacts neurodevelopment in youth with and without ADHD. [ABSTRACT FROM AUTHOR]

Background: The relationship between cannabis use and alcohol use disorders (AUDs) over time remains unclear. The current study used longitudinal data from adults in the United States (U.S.) to investigate the association between cannabis use and risk of onset and persistence of AUDs three years later. Methods: The study used data from respondents who completed both waves of the National Epidemiological Study of Alcohol Use and Related Disorders (NESARC; Wave 1, 2001-2001; Wave 2, 2004-2005) and for whom the age of first cannabis use preceded the age of any AUD. Incident AUDs were examined among respondents with no lifetime AUD diagnosis at Wave 1 (n=27,461). Persistent AUDs were examined among respondents with a lifetime AUD diagnosis at Wave 1 (n=2,121). Results: Among adults with no history of AUD, cannabis use at Wave 1 was associated with increased incidence of an AUD three years later relative to no cannabis use (Odds Ratio (OR)=5.43; 95% Confidence Interval (CI)=4.54-6.49). Among adults with a history of AUD, cannabis use at Wave 1 was associated with increased likelihood of AUD persistence three years later relative to no cannabis use (OR=1.74; 95% CI=1.56-1.95). These relationships remained significant after controlling for demographics, psychiatric disorders, and other substance use disorders. Conclusions: Cannabis use is associated with increased risk of AUD onset and persistence over the course of three years among U.S. adults. Community-based and clinical programs aimed at preventing or treating problematic alcohol use may benefit from integrating information about cannabis use in order to improve outcomes. [ABSTRACT FROM AUTHOR]

Introduction: Electronic screening and brief intervention has been identified as a low cost strategy to address marijuana use among students, however there is little known about who may be most responsive to this intervention approach. This study examined whether readiness-to-change moderated the influence of a web-based intervention on frequency of use at 3-month outcomes.Methods: One-hundred twenty-three students who smoked marijuana at least monthly were identified by screening in a student health center. Baseline and 3-month outcome assessments were conducted on-line. Participants were randomly assigned to either eCHECKUP TO GO-marijuana or a control condition after completing marijuana measures and the Readiness-to-Change Questionnaire (RTCQ). Negative binomial regression analyses were conducted to examine whether the effect of the intervention on marijuana use at 3-month outcomes was moderated by the Action and Problem Recognition dimensions of the RTCQ, adjusting for baseline use.Results: Analyses showed a significant Intervention × Action interaction. Probing of interaction effects showed that among those with high scores on the Action scale participants in the intervention group reported significantly fewer days of use than those in the control condition at follow-up (IRR=0.53, 95%CI: 0.94, 2.08). The Problem Recognition dimension did not moderate the influence of the intervention on outcomes.Conclusion: These results suggest that this eSBI may bolster change efforts among students who have begun taking steps toward changing their marijuana use. [ABSTRACT FROM AUTHOR]

Background: There is a developing body of research looking at cannabis use opportunity, but little research examining timing of opportunity to use cannabis.Aims: Identify factors associated with (1) earlier opportunity to use cannabis and (2) faster progression from opportunity to cannabis dependence.Method: Cross-sectional study of 3824 Australian twins and siblings, measuring age of onset of cannabis use opportunity and DSM-IV cannabis dependence. Survival analysis identified factors associated with faster progression to opportunity or dependence.Results: Factors associated with both speed of progression to opportunity and dependence were conduct disorder (opportunity HR 5.57, 95%CI 1.52-20.47; dependence HR 2.49, 95%CI 1.91-3.25), parental drug problems (opportunity HR 7.29, 95%CI 1.74-30.62; dependence HR 3.30, 95%CI 1.63-6.69), weekly tobacco use (opportunity HR 8.57, 95%CI 3.93-18.68; dependence HR 2.76, 95% CI 2.10-3.64), and female gender (opportunity HR 0.69, 95%CI 0.64-0.75; dependence HR 0.44, 95%CI 0.34-0.55). Frequent childhood religious attendance (HR 0.74, 95%CI 0.68-0.80), parental conflict (HR 1.09, 95%CI 1.00-1.18), parental alcohol problems (HR 1.19, 95%CI 1.08-1.30) and childhood sexual abuse (HR 1.17, 95%CI 1.01-1.34) were uniquely associated with transition to opportunity. Depressive episode (HR 1.44, 95%CI 1.12-1.85), tobacco dependence (HR 1.36, 95%CI 1.04-1.78), alcohol dependence (HR 2.64, 95%CI 1.53-4.58), other drug use (HR 2.10, 95%CI 1.64-2.69) and other drug dependence (HR 2.75, 95%CI 1.70-4.43) were uniquely associated with progression to dependence.Conclusion: The profile of factors associated with opportunity to use cannabis and dependence only partially overlaps, suggesting targeting of interventions may benefit from being tailored to the stages of drug use. [ABSTRACT FROM AUTHOR]

Background: Cannabis use disorder is associated with substantial morbidity and, after alcohol, is the most common drug bringing adolescents and adults into treatment. At present, there are no FDA-approved medications for cannabis use disorder. Combined pharmacologic interventions might be particularly useful in mitigating withdrawal symptoms and promoting abstinence.Objective: The purpose of this study was to evaluate the safety and efficacy of dronabinol, a synthetic form of delta-9-tetrahydrocannabinol, a naturally occurring pharmacologically active component of marijuana, and lofexidine, an alpha-2 agonist, in treating cannabis dependence.Methods: One hundred fifty six cannabis-dependent adults were enrolled and following a 1-week placebo lead-in phase 122 were randomized in a double-blind, placebo-controlled, 11-week trial. Participants were randomized to receive dronabinol 20mg three times a day and lofexidine 0.6 mg three times a day or placebo. Medications were maintained until the end of week eight, were then tapered over two weeks and patients were monitored off medications during the last study week. All participants received weekly motivational enhancement and relapse prevention therapy. Marijuana use was assessed using the timeline follow-back method.Results: There was no significant difference between treatment groups in the proportion of participants who achieved 3 weeks of abstinence during the maintenance phase of the trial (27.9% for the medication group and 29.5% for the placebo group), although both groups showed a reduction over time.Conclusions: Based on this treatment study, the combined intervention did not show promise as a treatment for cannabis use disorder. [ABSTRACT FROM AUTHOR]

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 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). 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. [ABSTRACT FROM AUTHOR]