US Epidemiology of Cannabis Use and Associated Problems

3-Year Follow-up of Lower Risk Cannabis Use Patterns: Evidence from a Longitudinal Survey

OBJECTIVES

Following recommendations from the Lower Risk Cannabis Use Guidelines, we evaluated how lower risk cannabis use (late initiation and low use frequency) was associated with the risk of developing cannabis abuse/dependence over a 3-year follow-up period compared to 12-month abstinence (controls) or higher risk cannabis use (early initiation and higher use frequency). We also explored the effect of cannabis quantity.

METHODS

Data were obtained from the U.S. nationally representative survey, National Epidemiologic Survey on Alcohol and Related Conditions wave I (2001 to 2002) and wave II (2004 to 2005), which included 31,464 respondents with no lifetime history of cannabis abuse/dependence at the first interview. We applied multiple logistic regression and propensity score matching analyses to examine the association between different use patterns at wave I and cannabis abuse/dependence at wave II, adjusting for covariates. Lower risk cannabis use and the transition to higher use frequency were also assessed.

RESULTS

For propensity score analysis, lower risk cannabis use at wave I was associated with higher risk of cannabis use/dependence at wave II compared to controls (odds ratio [OR]: 4.27; 95% confidence interval [95% CI], 1.57 to 11.61); however, there was no association with use frequency increase (OR: 2.52; 95% CI, 0.88 to 7.17). Higher risk use had a greater risk of cannabis use/dependence than controls (OR: 6.27; 95% CI, 2.56 to 15.38) and lower risk use (OR: 2.69; 95% CI, 1.12 to 6.47). Logistic regression analyses showed similar results, except that lower risk use was significantly associated with use frequency increase (OR: 2.49; 95% CI, 1.22 to 5.08). For the lower risk use group, 1 to 3 joints/day of use was significantly associated with cannabis abuse/dependence.

CONCLUSIONS

We found that following recommended use patterns can significantly lower one's risk of cannabis abuse/dependence. However, risk of cannabis abuse/dependence is still 4 times higher than staying abstinent. Updated recommendations on safe cannabis exposure levels are needed to guide cannabis use in the general population after cannabis legalization.

Getting High or Getting By? An Examination of Cannabis Motives, Cannabis Misuse, and Concurrent Psychopathology in a Sample of General Community Adults

OBJECTIVE:

Few studies have examined cannabis motives in adults and, although associations between cannabis use and psychiatric conditions are well documented, there has been limited investigation of the intersection of cannabis use, cannabis motives, and psychopathology. In a sample of community adults, the present study examined cannabis motives in relation to cannabis misuse, and investigated whether motives linked cannabis misuse with concurrent psychiatric symptoms.

METHOD:

Participants (N = 395; M_age = 34.8; %F = 47.6; % White = 81.3%) completed assessments related to cannabis misuse, cannabis use motives, and symptoms of depression, anxiety, PTSD, and somatic experiences. Bivariate correlations, hierarchical regressions, and indirect effect analyses were performed to examine associations between motives and cannabis misuse and to investigate mechanistic relationships between psychiatric symptoms and cannabis misuse.

RESULTS:

Regressions revealed significant associations between cannabis misuse and social (β = .13, P < .02), enhancement (β = .12, P < .02), and coping motives (β = .48, P < .001). Indirect effects were present such that coping motives consistently linked psychiatric and somatic symptoms with cannabis misuse (anxiety: unstandardized effect = 0.26,and 95% CI = 0.17-0.37; depression: unstandardized effect = 0.12, CI = 0.11-0.25; PTSD: unstandardized effect = 0.07, CI = 0.04-0.10; somatic symptoms: unstandardized effect = 0.20, CI = 0.11-0.30). In addition, enhancement motives exhibited an indirect effect (unstandardized effect = 0.02, CI = 0.002-0.04) between depressive symptoms and cannabis misuse.

CONCLUSION:

These results support a negative reinforcement motivational profile as the predominant pattern in adult cannabis users, albeit with links to enhancement and social motives. This motivational profile is especially pronounced with regard to comorbid psychopathology and cannabis misuse. These results support the importance of treatment strategies targeting maladaptive coping to address cannabis misuse and co-occurring psychopathology.

Aberrant Salience among Young Healthy Postgraduate University Students: The Role of Cannabis Use, Psychotic-Like Experiences, and Personality

Aberrant salience (AS) is an anomalous world experience which plays a major role in psychotic proneness. In the general population, a deployment of this construct - encompassing personality traits, psychotic-like symptoms, and cannabis use - could prove useful to outline the relative importance of these factors. For this purpose, 106 postgraduate university students filled the AS Inventory (ASI), the Community Assessment of Psychic Experiences (CAPE), the Temperament and Character Inventory (TCI), and the Symptom Checklist 90-Revised (SCL-90-R). Lifetime cannabis users (n = 56) and individuals who did not use cannabis (n = 50) were compared. The role of cannabis use and psychometric indexes on ASI total scores was tested in different subgroups (overall sample, cannabis users, and nonusers). The present study confirmed that cannabis users presented higher ASI scores. The deployment of AS proved to involve positive symptom frequency (assessed through CAPE), character dimensions of self-directedness and self-transcendence (TCI subscales), and cannabis use. Among nonusers, the role of personality traits (assessed through the TCI) was preeminent, whereas positive psychotic-like experiences (measured by means of CAPE) had a major weight among cannabis users. The present study suggests that pre-reflexive anomalous world experiences such as AS are intertwined with reflexive self-consciousness, personality traits, current subclinical psychotic symptoms, and cannabis use. In the present study, subthreshold psychotic experiences proved to play a major role among cannabis users, whereas personality appeared to be more relevant among nonusers.

Cannabinoids in the Treatment of Cannabis Use Disorder: Systematic Review of Randomized Controlled Trials

BACKGROUND

The prevalence of cannabis use and cannabis use disorders (CUD) has significantly increased over time. However, there are no approved pharmacological treatments for CUD. The aim of this study was to determine the efficacy and safety of various medical cannabinoids in the treatment of CUD.

METHODS

We conducted a systematic review of randomized controlled trials which evaluated the therapeutic potential of medical cannabinoids in individuals with CUD and summarized the main study outcomes in terms of cannabis use, abstinence, withdrawal symptoms, craving, retention in treatment and adverse events.

RESULTS

We identified eight trials with a total of 667 study participants. Dronabinol reduced cannabis withdrawal symptoms whereas nabiximols, cannabidiol and PF-04457845, a fatty acid amide inhibitor, also reduced cannabis use and improved abstinence, compared to placebo. Nabilone failed to demonstrate efficacy in the treatment of CUD. All medications were well-tolerated.

CONCLUSIONS

Cannabinoid receptor agonists, i.e., dronabinol and nabilone, showed only limited or no therapeutic potential in the treatment of CUD. In contrast, modulators of endocannabinoid activity, i.e., nabiximols, cannabidiol and PF-04457845, demonstrated broader efficacy which covered almost all aspects of CUD. Endocannabinoid modulation appears to be a promising treatment approach in CUD, but the evidence to support this strategy is still small and future research in this direction is needed.

Associations between Local Jurisdiction Ordinances and Current Use of Cannabis Products in California Adolescents

PURPOSE

Cannabis use among adolescents may have detrimental effects and use among this age group is increasing. It is important to understand how expansion of laws permitting cannabis sales may impact adolescent use. Much of the current research has explored how state-level policy decisions may impact adolescents' use behaviors; however, there is a gap in the understanding of how differences in local jurisdictional policies may also influence underage cannabis use.Procedures: The present study cross-sectionally assesses local variation in cannabis policies to explore the potential effects of local policy on underage use behaviors. Data were collected from (N = 1,573) adolescents representing 120 different localities across California, collected as a part of Project Cal Teens. Linear regression models were used to assess associations between local jurisdiction's allowance of retail sale of cannabis for adult-use and past 30-day use of non-medical (adult use) cannabis and perceived access to cannabis products.

FINDINGS

Local policy allowing cannabis retail was associated with adolescents' significantly higher past 30-day use of cannabis (β = 0.25 95% CI = 0.08, 0.42) and perceived access (β = 0.60 95% CI = 0.27, 0.94).

CONCLUSIONS

Results highlight the impact of local cannabis policies on adolescent cannabis use and perception. Considering the effects of cannabis use on adolescent development, this is an important public health concern because 14 states have already legalized recreational retail sales and growing numbers of local jurisdictions are allowing the retail sale of recreational cannabis.

Results from a randomized, double-blind, placebo-controlled, crossover, multimodal-MRI pilot study of gabapentin for co-occurring bipolar and cannabis use disorders

Disrupted brain gamma-aminobutyric acid (GABA)/glutamate homeostasis is a promising target for pharmacological intervention in co-occurring bipolar disorder (BD) and cannabis use disorder (CUD). Gabapentin is a safe and well-tolerated medication, FDA-approved to treat other neurological diseases, that restores GABA/glutamate homeostasis, with treatment studies supporting efficacy in treating CUD, as well as anxiety and sleep disorders that are common to both BD and CUD. The present manuscript represents the primary report of a randomized, double-blind, placebo-controlled, crossover (1-week/condition), multimodal-MRI (proton-MR spectroscopy, functional MRI) pilot study of gabapentin (1200 mg/day) in BD + CUD (n = 22). Primary analyses revealed that (1) gabapentin was well tolerated and adherence and retention were high, (2) gabapentin increased dorsal anterior cingulate cortex (dACC) and right basal ganglia (rBG) glutamate levels and (3) gabapentin increased activation to visual cannabis cues in the posterior midcingulate cortex (pMCC, a region involved in response inhibition to rewarding stimuli). Exploratory evaluation of clinical outcomes further found that in participants taking gabapentin versus placebo, (1) elevations of dACC GABA levels were associated with lower manic/mixed and depressive symptoms and (2) elevations of rBG glutamate levels and pMCC activation to cannabis cues were associated with lower cannabis use. Though promising, the findings from this study should be interpreted with caution due to observed randomization order effects on dACC glutamate levels and identification of statistical moderators that differed by randomization order (i.e. cigarette-smoking status on rBG glutamate levels and pMCC cue activation). Nonetheless, they provide the necessary foundation for a more robustly designed (urn-randomized, parallel-group) future study of adjuvant gabapentin for BD + CUD.

Prevalence of Cannabis Use and Cannabis Route of Administration among Massachusetts Adults in Buprenorphine Treatment for Opioid Use Disorder

BACKGROUND

Recent prevalence estimates of cannabis use among individuals receiving medication treatment for OUD (MOUD) are lacking, and no study has characterized cannabis route of administration (cROA) in this population. These knowledge gaps are relevant because cannabis' effects and health outcomes vary by cROA and the availability and perceptions of cROA (e.g., vaping devices) are changing.

METHODS

The Vaping In Buprenorphine-treated patients Evaluation (VIBE) cross-sectional survey assessed the prevalence and correlates of cannabis use and cROA among adults receiving buprenorphine MOUD from 02/20 to 07/20 at five community health centers in Massachusetts, a state with legal recreational and medical cannabis use.

RESULTS

Among the 92/222 (41%) respondents reporting past 30-day cannabis use, smoking was the most common cROA (75%), followed by vaping (38%), and eating (26%). Smoking was more often used as a single cROA vs. in combination others (p = 0.01), whereas vaping, eating, and dabbing were more often used in combination with another cROA (all p < 0.05). Of the 39% of participants reporting multiple cROA, smoking and vaping (61%), and smoking and eating (50%), were the most prevalent combinations. Nonwhite race (vs. white) and current cigarette smoking (vs. no nicotine use) were associated with past 30-day cannabis use in multiple logistic regression.

CONCLUSIONS

Prevalence of past 30-day cannabis use among individuals receiving buprenorphine MOUD in Massachusetts in 2020 was nearly double the prevalence of cannabis use in Massachusetts' adult general population in 2019 (21%). Our data are consistent with state and national data showing smoking as the most common cROA.

Association of Comorbid Behavioral and Medical Conditions With Cannabis Use Disorder in Pregnancy

IMPORTANCE

Prenatal cannabis use continues to increase, yet studies of the demographic, psychiatric, and medical characteristics associated with cannabis use in pregnancy are limited by size and use of self-report, and often do not consider cannabis use disorder (CUD) or concomitant substance use disorders (SUDs). Understanding the factors associated with CUD in pregnancy is paramount for designing targeted interventions.

OBJECTIVE

To examine the prevalence of co-occurring psychiatric and medical conditions of US pregnant individuals hospitalized with and without CUD by concomitant SUDs.

DESIGN, SETTING, AND PARTICIPANTS

The study analyzed restricted hospital discharge data from the 2010 to 2018 Healthcare Cost and Utilization Project State Inpatient Databases in 35 states. Data were analyzed from January to August 2021. Weighted linear regressions tested whether the prevalence of psychiatric and medical conditions differed between individuals with and without a CUD diagnosis at hospitalization. Inpatient hospitalizations of pregnant patients aged 15 to 44 years with a CUD diagnosis were identified. Pregnant patients aged 15 to 44 years without a CUD diagnosis were identified for comparison. Patients were further stratified based on concomitant SUD patterns: (1) other SUDs, including at least 1 controlled substance; (2) other SUDs, excluding controlled substances; and (3) no other SUDs.

EXPOSURES

CUD in pregnancy.

MAIN OUTCOMES AND MEASURES

Prevalence of demographic characteristics, psychiatric disorders (eg, depression and anxiety), and medical conditions (eg, epilepsy and vomiting).

RESULTS

The sample included 20 914 591 hospitalizations of individuals who were pregnant. The mean (SD) age was 28.24 (5.85) years. Of the total number of hospitalizations, 249 084 (1.19%) involved CUD and 20 665 507 (98.81%) did not. The proportion of prenatal hospitalizations involving CUD increased from 0.008 in 2010 to 0.02 in 2018. Analyses showed significant differences in the prevalence of almost every medical and psychiatric outcome examined between hospitalizations with and without CUD diagnoses, regardless of concomitant SUDs. Elevations were seen in depression (0.089; 95% CI, 0.083-0.095), anxiety (0.072; 95% CI, 0.066-0.076), and nausea (0.036; 95% CI, 0.033-0.040]) among individuals with CUD only at hospitalization compared with individuals with no SUDs at hospitalization.

CONCLUSIONS AND RELEVANCE

Considerable growth was observed in the prevalence of CUD diagnoses among individuals hospitalized prenatally and in the prevalence of depression, anxiety, nausea, and other conditions in individuals with CUD at hospitalization. This study highlights the need for more screening, prevention, and treatment, particularly in populations with co-occurring CUD and psychiatric disorders. Research on the determinants and outcomes associated with CUD during pregnancy is needed to guide clinicians, policy makers, and patients in making informed decisions.

Young Adult Cannabis Users' Perceptions of Cannabis Risks and Benefits by Chronic Pain Status

Purpose: Young adults experiencing chronic pain may self-medicate with cannabis. We examined perceived risks and benefits of cannabis use among young adult users by chronic pain status, and identified relationships among perceived risks and benefits, physical and mental health, and cannabis-related problems. Methods: Young adults reporting at least weekly cannabis use (N = 176, 50.9% with chronic pain) reported perceptions of lifetime risks and benefits associated with cannabis use, physical and mental health, and cannabis-related problems. Results: Young adults without chronic pain reported better physical and mental health than those with chronic pain. Cannabis use, problems, and risk and benefit perceptions did not differ by pain status. Risk and benefit perceptions were unrelated to physical health, perceiving fewer risks and more benefits was associated with better mental health, and perceiving more risk was associated with cannabis problems. Chronic pain status moderated the relationship between perceived benefits and outcomes, such that perceiving more benefits was associated with better physical health for those without chronic pain. Further, greater perceived benefits were associated with more cannabis-related problems for those without chronic pain but fewer problems for those with chronic pain. Conclusion: This study offers insight into the perceptions of risks and benefits among young adult cannabis users and associations with physical and mental health and cannabis-related problems. The effects of perceived benefits on physical health and cannabis-related problems differs for young adults with and without pain, suggesting assessment and consideration of pain status may be valuable in intervention contexts.

Lower-Risk Cannabis Use Guidelines (LRCUG) for reducing health harms from non-medical cannabis use: A comprehensive evidence and recommendations update

BACKGROUND

Cannabis use is common, especially among young people, and is associated with risks for various health harms. Some jurisdictions have recently moved to legalization/regulation pursuing public health goals. Evidence-based 'Lower Risk Cannabis Use Guidelines' (LRCUG) and recommendations were previously developed to reduce modifiable risk factors of cannabis-related adverse health outcomes; related evidence has evolved substantially since. We aimed to review new scientific evidence and to develop comprehensively up-to-date LRCUG, including their recommendations, on this evidence basis.

METHODS

Targeted searches for literature (since 2016) on main risk factors for cannabis-related adverse health outcomes modifiable by the user-individual were conducted. Topical areas were informed by previous LRCUG content and expanded upon current evidence. Searches preferentially focused on systematic reviews, supplemented by key individual studies. The review results were evidence-graded, topically organized and narratively summarized; recommendations were developed through an iterative scientific expert consensus development process.

RESULTS

A substantial body of modifiable risk factors for cannabis use-related health harms were identified with varying evidence quality. Twelve substantive recommendation clusters and three precautionary statements were developed. In general, current evidence suggests that individuals can substantially reduce their risk for adverse health outcomes if they delay the onset of cannabis use until after adolescence, avoid the use of high-potency (THC) cannabis products and high-frequency/-intensity of use, and refrain from smoking-routes for administration. While young people are particularly vulnerable to cannabis-related harms, other sub-groups (e.g., pregnant women, drivers, older adults, those with co-morbidities) are advised to exercise particular caution with use-related risks. Legal/regulated cannabis products should be used where possible.

CONCLUSIONS

Cannabis use can result in adverse health outcomes, mostly among sub-groups with higher-risk use. Reducing the risk factors identified can help to reduce health harms from use. The LRCUG offer one targeted intervention component within a comprehensive public health approach for cannabis use. They require effective audience-tailoring and dissemination, regular updating as new evidence become available, and should be evaluated for their impact.

Prospective effects of loneliness on frequency of alcohol and marijuana use

BACKGROUND

Loneliness is a widespread problem, with demonstrated negative health effects. However, prospective data on the relationship between loneliness and problematic substance use are lacking, and few studies have examined specific commonplace substances, such as alcohol and cannabis. This study used prospective data from a community sample of US adults with problematic alcohol or cannabis use to examine whether loneliness was a predictor of subsequent increased substance use.

METHODS

Participants (N = 210) were recruited between 05/2016-06/2019 from a New York City medical center. At baseline, 3-month, and 6-month follow-ups, participants completed identical computerized questionnaires. We used generalized estimating equations to assess the average effect of past 2-week loneliness on subsequent number of days of alcohol or cannabis use, controlling for baseline days of use, demographic characteristics, and past 2-week DSM-5 depression.

RESULTS

Compared with individuals who were never lonely, participants with moderate or severe loneliness had a significantly higher frequency of alcohol or cannabis use at the subsequent assessment (β = 0.25 95% CI: 0.08-0.42).

CONCLUSION

Individuals experiencing loneliness at least a few times in the past 2 weeks reported more days of subsequent alcohol or cannabis use compared with individuals who were not lonely. This is cause for concern, as national surveys of US adults indicate increasing rates of loneliness, depression and substance use during the COVID-19 pandemic. These results suggest the need for health care providers to screen for feelings of loneliness and potentially harmful coping behaviors such as substance use, and to offer healthier alternative coping strategies.

Simultaneous use of marijuana and alcohol: Potential prevention targets among young adults who use alcohol

Simultaneous alcohol and marijuana use (SAM) such that their effects overlap has emerged as a behavior that is riskier than using either substance separately. It has been associated with high-risk binge drinking and driving while intoxicated during young adulthood, and it has been demonstrated to cause greater physical and mental impairment than use of alcohol or marijuana separately. To identify intervention and prevention targets specific to SAM, we examined the relationships between alcohol- and marijuana-specific beliefs and attitudes (risk factors) and self-reported SAM compared to non-simultaneous co-use (CAM) and alcohol use only in the past 30 days in a sample of young adults (n = 1,023, mean age = 23.17; SD = 0.43). Of those who reported drinking alcohol in the past 30 days, 20.7% reported SAM, 12.6% reported CAM, and 66.6% reported using only alcohol. Results from multinomial logistic regression analyses indicated that some marijuana-specific risk factors (e.g., belief that it is not at all wrong for someone their age to use marijuana) differentiated SAM or CAM from alcohol use only, but alcohol-specific risk factors generally did not. However, the perceptions that parents approved of their using marijuana or frequently drinking heavily were associated with a greater likelihood of SAM compared to CAM (OR ranged from 2.25 to 3.53). Findings point to the salience of individuals' attitudes and beliefs around marijuana use and their perception of parental approval of heavy drinking and marijuana use as potential targets for prevention programs targeting risk reduction among young adults.

Changes in alcohol use by cannabis use status among adolescents and young adults in the United States: Emerging evidence for both substitution and complementarity

BACKGROUND

The majority of adolescents and young adults (AYA) who use cannabis also use alcohol. Although cannabis use is increasing in the United States (US), it is not known whether the increase contributes to either increased co-use of alcohol and cannabis (e.g., complementarity) or replacement of alcohol with cannabis (e.g., substitution). The current study estimated the prevalence of alcohol use by cannabis use status among US AYA ages 12 to 25 in 2018 and trends in alcohol use by cannabis use status from 2002 to 2018.

METHODS

Data were drawn from the 2002 to 2018 National Survey on Drug Use and Health public use data files. The analytic sample included AYA ages 12 to 25 (2018 sample, n = 26,924; total combined sample 2002 to 2018, n = 576,053). Linear and logistic regression models were used to estimate past-month alcohol use, daily alcohol use, and average quantity of alcohol consumed among AYA with and without past-month cannabis use from 2002 to 2018.

RESULTS

In 2018, any alcohol use and daily alcohol use were significantly more common among AYA who used cannabis use than those who did not use cannabis. Overall, any alcohol use, daily alcohol use, and average drinks per day declined from 2002 to 2018 among AYA irrespective of recent cannabis use. However, the decline in any alcohol use, daily alcohol use, and average alcohol drinks per day was more rapid among AYA who used cannabis (daily and nondaily) than those who did not use cannabis. The rate of decline in average alcohol drinks per day was also higher among AYA with daily compared to nondaily cannabis use.

CONCLUSIONS

Even with declines in alcohol use over time, drinking is much more common among AYA who report cannabis than those without recent cannabis use, which is consistent with complementarity. Yet, because the decline in alcohol use has been more rapid among AYA who use cannabis, there is also evidence of substitution. Thus, the current data on alcohol and cannabis use are consistent with both complementarity and substitution. However, these relationships may change as cannabis legalization expands over time.

Marijuana use and high-risk health behaviors among diverse college students post- legalization of recreational marijuana use

Objectives

This study examined high-risk health behaviors in marijuana-users among a diverse college population in Southern California, post legalization of marijuana for recreational use.

Study design

A cross-sectional research design was employed utilizing existing data via the 2018 National College Health Assessment (NCHA) from a large Minority-Serving Institution (MSI) population [n = 1345 (Hispanic/Latino/a, n = 456; White, n = 353; Asian Pacific Islander (API), n = 288; Multiracial/Biracial, n = 195; Other, n = 53)].

Methods

Chi square and t-tests assessed differences in descriptive characteristics (age, gender, race/ethnicity and GPA) and high-risk behaviors (alcohol, tobacco and sexual behaviors) among marijuana users and non-users. Logistic regression analyses examined the relationship between race/ethnicity and high-risk behaviors with marijuana use (dependent variable).

Results

Among marijuana-users, significant (p = 0.004) differences were observed between race/ethnicity with Whites reporting using most (32.7%), followed by Hispanics (27.6%) and then APIs (17.8%). Marijuana-users compared with non-users consistently reported high-risk alcohol behaviors (p < 0.0001), were more likely to smoke tobacco (p < 0.0001) and engaged in more high-risk sexual behaviors (p < 0.0001). Logistic regression showed after adjusting for demographic characteristics and high-risk behaviors, race/ethnicity was borderline significantly associated with marijuana use, specifically for Whites (OR = 1.53; 95% CI: (−0.01, 0.86), p = 0.06) and the Other race/ethnicity category (OR = 2.32; 95% CI: (0.12, 1.56), p = 0.02) compared with APIs.

Conclusion

Our findings clearly demonstrate deleterious high-risk behaviors such as alcohol use, tobacco use, and certain sexual behaviors occur more among marijuana-users compared to non-users, post legalization of marijuana for recreational use. Further, race-ethnic differences were observed. Therefore, continued examination of marijuana use trends and high-risk behaviors is critical in monitoring the implications of marijuana policy changes, specifically in diverse populations.

Genetic Liability to Cannabis Use Disorder and COVID-19 Hospitalization

BACKGROUND

Vulnerability to COVID-19 hospitalization has been linked to behavioral risk factors, including combustible psychoactive substance use (e.g., tobacco smoking). Paralleling the COVID-19 pandemic crisis have been increasingly permissive laws for recreational cannabis use. Cannabis use disorder (CUD) is a psychiatric disorder that is heritable and genetically correlated with respiratory disease, independent of tobacco smoking. We examined the genetic relationship between CUD and COVID-19 hospitalization.

METHODS

We estimated the genetic correlation between CUD (case: n = 14,080; control: n = 343,726) and COVID-19 hospitalization (case: n = 9373; control: n = 1,197,256) using summary statistics from genome-wide association studies. Using independent genome-wide association studies conducted before the pandemic, we controlled for several covariates (i.e., tobacco use phenotypes, problematic alcohol use, body mass index, fasting glucose, forced expiratory volume, education attainment, risk taking, attention-deficit/hyperactivity disorder, Townsend deprivation index, chronic obstructive pulmonary disease, hypertension, and type 2 diabetes) using genomic structural equation modeling. Genetic causality between CUD and COVID-19 hospitalization was estimated using latent causal variable models.

RESULTS

Genetic vulnerability to COVID-19 was correlated with genetic liability to CUD (r G  = 0.423 [SE = 0.0965], p = 1.33 × 10-6); this association remained when accounting for genetic liability to related risk factors and covariates (b = 0.381-0.539, p = .012-.049). Latent causal variable analysis revealed causal effect estimates that were not statistically significant.

CONCLUSIONS

Problematic cannabis use and vulnerability to serious COVID-19 complications share genetic underpinnings that are unique from common correlates. While CUD may plausibly contribute to severe COVID-19 presentations, causal inference models yielded no evidence of putative causation. Curbing excessive cannabis use may mitigate the impact of COVID-19.

Psychosocial and health problems associated with alcohol use disorder and cannabis use disorder in U.S. adults

BACKGROUND

Although the problems associated with alcohol use disorder (AUD) are well known, little is known about the psychosocial problems associated with cannabis use disorder (CUD), and the harmfulness of CUD relative to AUD. We compared the odds of psychosocial and health-related problems between individuals with DSM-5 AUD-only, CUD-only and co-occurring AUD+CUD.

METHODS

The 2012-2013 NESARC-III, a nationally representative cross-sectional survey of non-institutionalized US adults (n = 36,309), assessed participants for DSM-5 AUD, CUD, and psychosocial (interpersonal, financial, legal) and health-related problems. Based on their responses, participants were categorized into mutually exclusive groups: no AUD/CUD, AUD-only, CUD-only, and AUD+CUD. Multivariable logistic regression models examined the associations between psychosocial problems and the four AUD/CUD groups, adjusting for sociodemographic characteristics.

RESULTS

People with AUD-only, CUD-only, and AUD+CUD had higher odds of most interpersonal problems (adjusted odds ratio [aORs] 1.07-4.01), financial problems (aORs 1.53-4.28), legal problems (aORs 3.34-7.71), and health-related problems (aORs 1.29-1.92). The odds of psychosocial and health-related problems were similar for CUD-only and AUD-only in direct comparisons. Compared to those with AUD-only, those with AUD+CUD had higher odds of most problems examined (aORs 1.42-2.31). In contrast, there were few differences when comparing AUD+CUD with CUD-only.

CONCLUSIONS

AUD and CUD were similarly associated with interpersonal, financial, and legal problems, emergency treatment and suicide attempt. People with AUD+CUD had higher odds of certain problems than individuals with either AUD-only or CUD-only. Although most people who use cannabis do not experience harms, our results indicate that CUD does not appear to be less harmful than AUD.

The role of aberrant salience in the association between cannabis use frequency and psychotic experiences among racial and ethnic minoritized youth

Prior studies have shown cannabis use is correlated with psychotic symptoms, but few have explored potential underlying mechanisms. The present study examined whether aberrant salience explains the association between cannabis use frequency and psychotic experiences (PE) while accounting for the mediating role of anxiety in this association. A US urban undergraduate sample of 816 racial and ethnic minorities contributed data used in linear regression models to determine associations between recent (3 months) cannabis use frequency, aberrant salience, anxiety, positive subscale Prodromal Questionnaire (PQ) items, and distressing positive PQ items. Results from hierarchical linear regression and mediation models using Hayes PROCESS application indicated the association between cannabis use frequency and PE was significantly explained by higher aberrant salience and anxiety. Furthermore, anxiety's indirect association with cannabis use frequency and PE significantly occurred through aberrant salience's indirect association with cannabis use frequency and PE (i.e., serial mediation). A similar pattern emerged for distressing PE. We also found earlier age of cannabis use onset (age 12-14) was associated with a higher number of PE and distressing PE and that this was partially explained by higher aberrant salience. Anxiety's indirect association between earlier age of onset and PE/distressing PE only occurred through aberrant salience (i.e., serial mediation). Aberrant salience may be the part of psychosis proneness most directly connected to why earlier initiation of cannabis use is a risk factor for psychotic disorders. This should be explored further in future longitudinal work with clinical high-risk populations and among minoritized youth.

Cannabinoids for the treatment of cannabis use disorder: New avenues for reaching and helping youth?

Cannabis use peaks during adolescence and emerging adulthood, and cannabis use disorder (CUD) is associated with a wide range of adverse outcomes. This is particularly pertinent in youth, because the developing brain may be more vulnerable to adverse effects of frequent cannabis use. Combining evidence-based psychosocial interventions with safe and effective pharmacotherapy is a potential avenue to improve youth outcomes, but we lack approved CUD pharmacotherapies. Here, we review new potential avenues for helping youth with CUD, with a particular focus on cannabinoid-based treatments. Evidence from placebo-controlled RCTs suggests synthetic delta-9-tetrahydrocannabinol (THC) decreases withdrawal symptoms, but not cannabis use, in adults with daily cannabis use/CUD, while findings regarding formulations containing THC combined with cannabidiol (CBD) are mixed. Preliminary evidence from two placebo-controlled RCTs in adults with CUD suggests that both Fatty Acid Amide Hydrolase inhibitors and CBD can reduce cannabis use. However, larger trials are needed to strengthen the evidence. Findings from adults point to cannabinoid-based treatments as a potential strategy that should be examined in youth with CUD.

Instrumental Substance Use Among Youth with Rheumatic Disease-A Biopsychosocial Model

Youth with chronic medical conditions (YCMC) including rheumatic disease use substances and may experience harms from doing so. The chronic illness experience may amplify substance use risks for some YCMC who may use to ameliorate symptoms of disease activity and negative side effects of medications, so-called "instrumental use." This article provides a brief overview of adolescent substance use, its intersection with chronic illness, and pediatric-onset rheumatic disease (PRD). A biopsychosocial model of substance use vulnerability for youth with PRD is presented along with emerging evidence about instrumental use of substances. Implications for PRD clinical practice are discussed.

Cannabidiol Does Not Cause Significant Changes to Working Memory Performance in the N-Back Task

Cannabis use can be traced back to several centuries before the Common Era, when it was used for industrial, medicinal and recreational purposes. More recently, over 100 different cannabinoid compounds have been identified, one of which is cannabidiol (CBD), a compound widely used for anti-inflammatory and anxiolytic treatment. The literature surrounding the cognitive effects of CBD is limited, with most studies focusing on the effects of other cannabinoids on cognition. To expand this literature, this study investigated whether CBD causes significant differences to working memory (WM) functioning, as measured by the N-back task. It was hypothesised that CBD does not cause statistically significant differences to WM. In all, 54 participants, 33 females and 21 males, were recruited, with a mean age of 32.63 years. Of these 54 participants, 26 reported using CBD and no other cannabinoids, while 28 reported not using any cannabinoid. The participants were instructed to answer a short online survey to gather basic demographic data and to complete an online N-back task to measure WM. For the computerised N-back task, the participants completed a practice and three test blocks, where they were instructed to respond to whether a series of letter stimuli were presented one trial back (1-back), two trials back (2-back) or three trials back (3-back). Multivariate analysis of covariance yielded no statistically significant difference on either response time or response accuracy data between groups after controlling for how long the participants use CBD and for what reason they use CBD. These results support our hypothesis that CBD does not cause significant changes to WM functioning. Further research is greatly needed to investigate the long-term effects of CBD use on WM and on general cognitive functioning.

Sociodemographic Characteristics Associated With and Prevalence and Frequency of Cannabis Use Among Adults in the US

IMPORTANCE

Cannabis use has increased, but there are few studies on frequent and daily cannabis use among US adults. Individuals who engage in higher frequency use may suffer more health consequences.

OBJECTIVE

To examine frequency of cannabis use and associated factors among US adults.

DESIGN, SETTING, AND PARTICIPANTS

This survey study included data from 21 US states and 2 US territories reported in the Behavioral Risk Factor Surveillance System surveys from 2016 to 2019. Cross-sectional data on US adults ages 18 years and older were used to estimate demographic, socioeconomic, and behavioral risk factors for cannabis use, taking into account the survey strata and sampling weights for the 4 years of combined data. Using a multivariable ordinal logistic analysis, the association of demographic, socioeconomic status, and behavioral risk factors with past month cannabis frequency were examined.

EXPOSURES

Sociodemographic characteristic, ie, age, gender, race and ethnicity, educational attainment, employment status, and annual household income.

MAIN OUTCOMES AND MEASURES

Ordinal categorization of number of days of cannabis use in the past 30 days in terms of nonuse, infrequent use (1-5 days), frequent use (6-29 days), and daily use.

RESULTS

Among the 387 179 respondents, 58 009 (27.9%) were ages 18 to 34 years, 186 923 (50.3%) were ages 35 to 64 years, and 142 225 (21.8%) were age 65 years or older (mean [SD] age, 48.3 [0.1] years). The sample included 28 345 (9.8%) Black, 36 697 (22.6%) Hispanic, and 292 210 (57.3%) White respondents. Smoking was the most common form of cannabis use. The frequency of cannabis use varied significantly by age, gender, race, marital status, education, and employment. Higher frequency cannabis use was associated with younger age (ages 18-34 years: adjusted odds ratio [aOR],4.12; 95% CI, 3.63-4.68; ages 35-64 years: aOR,2.22; 95% CI, 1.98-2.49), Black (aOR, 1.46; 95% CI, 1.33-1.71) and Native American (aOR, 1.25; 95% CI, 1.04-1.52) race, and less educational attainment (high school or less: aOR,1.09; 95% CI, 1.02-1.17; some college: aOR,1.27; 95% CI, 1.19-1.35). Being married (aOR, 0.54; 95% CI, 0.51-0.58) or identifying as Asian (aOR, 0.60; 95% CI, 0.51-0.71) or Hispanic (aOR, 0.71; 95% CI, 0.65-0.77) was associated with lower-frequency cannabis use after accounting for other baseline factors.

CONCLUSIONS AND RELEVANCE

This nationally based study found that higher-frequency cannabis use is more common among young and racial minority populations, as well as respondents with low socioeconomic status. Given the known and emerging negative health effects of cannabis use, more attention may need to be paid to high-frequency use among underserved populations in the form of screening, risk stratification, and treatment.

Pharmacotherapies for cannabis use disorder: A systematic review and network meta-analysis

OBJECTIVE

This study aimed to determine the efficacy and acceptability of pharmacotherapies for cannabis use disorder (CUD).

METHODS

We conducted a systematic review and frequentist network meta-analysis, searching five electronic databases for randomized placebo-controlled trials of individuals diagnosed with CUD receiving pharmacotherapy with or without concomitant psychotherapy. Primary outcomes were the reduction in cannabis use and retention in treatment. Secondary outcomes were adverse events, discontinuation due to adverse events, total abstinence, withdrawal symptoms, cravings, and CUD severity. We applied a frequentist, random-effects Network Meta-Analysis model to pool effect sizes across trials using standardized mean differences (SMD, g) and rate ratios (RR) with their 95% confidence intervals.

RESULTS

We identified a total of 24 trials (n=1912, 74.9% male, mean age 30.2 years). Nabilone (d=-4.47 [-8.15; -0.79]), topiramate (d=-3.80 [-7.06; -0.54]), and fatty-acid amyl hydroxylase inhibitors (d=-2.30 [-4.75; 0.15]) reduced cannabis use relative to placebo. Dronabinol improved retention in treatment (RR=1.27 [1.02; 1.57]), while topiramate worsened treatment retention (RR=0.62 [0.42; 0.91]). Gabapentin reduced cannabis cravings (d=-2.42 [-3.53; -1.32], while vilazodone worsened craving severity (d=1.69 [0.71; 2.66]. Buspirone (RR=1.14 [1.00; 1.29]), venlafaxine (RR=1.78 [1.40; 2.26]), and topiramate (RR=9.10 [1.27; 65.11]) caused more adverse events, while topiramate caused more dropouts due to adverse events.

CONCLUSIONS

Based on this review, some medications appeared to show promise for treating individual aspects of CUD. However, there is a lack of robust evidence to support any particular pharmacological treatment. There is a need for additional studies to expand the evidence base for CUD pharmacotherapy. While medication strategies may become an integral component for CUD treatment one day, psychosocial interventions should remain the first line given the limitations in the available evidence.

Genetics of substance use disorders in the era of big data

Substance use disorders (SUDs) are conditions in which the use of legal or illegal substances, such as nicotine, alcohol or opioids, results in clinical and functional impairment. SUDs and, more generally, substance use are genetically complex traits that are enormously costly on an individual and societal basis. The past few years have seen remarkable progress in our understanding of the genetics, and therefore the biology, of substance use and abuse. Various studies - including of well-defined phenotypes in deeply phenotyped samples, as well as broadly defined phenotypes in meta-analysis and biobank samples - have revealed multiple risk loci for these common traits. A key emerging insight from this work establishes a biological and genetic distinction between quantity and/or frequency measures of substance use (which may involve low levels of use without dependence), versus symptoms related to physical dependence.

Patterns of drug overdose deaths in Kuwait from 2014 to 2018

Background

Kuwait is an Arabian Gulf couFntry with a population of around 4.4 million as of 2020. In recent years, government based news agencies have commonly exposed drug smuggling plots that were foiled by local authorities. We attempted to study the patterns of drug overdose deaths in Kuwait, which we believe is a good method to address the effect of illicit drug use in the country.

Methodology

All cases that were signed out as drug overdose death were collected from the General department of criminal evidence. The relationship between demographic factors and drug types were analyzed using various statistical methodologies.

Results

344 victims were identified from 2014 to 2018. The majority of whom were Kuwaiti nationals (67%) and the average age of death was 38. Hawalli governorate had the highest number of cases, while Jahra governorate had the least. Morphine appeared to be the most common drug found in the victims post mortem (79.9%) followed by benzodiazepines (43%). Our study has an extremely low female number of victims (2.6%). Some substances that are commonly abused globally eg heroin and cocaine were rarely recovered in our study. The number of cases have had an increase over the study period with the highest number of cases in 2018.

Conclusion

The current study is the first of its kind in Kuwait and one of the first in the middle east region. It is evident that illicit drug use and subsequent drug overdose deaths are on a rise in Kuwait and government agencies need to put a strategic plan to address and reduce this problem.

Cannabis use outcomes by past-month binge drinking status in the general United States population

Cannabis use and binge drinking are increasingly common in the United States, yet little is known about cannabis use patterns among people who engage in binge drinking. This study explored the relationship between several cannabis use outcomes and past-month binge drinking status. Pooled 2015-2018 National Surveys on Drug Use and Health data (N = 226,632) were used to explore the hypothesis that binge drinking is associated with higher prevalence of cannabis outcomes. Cannabis outcomes included past-month and past-year use, daily/almost daily use, and past-year DSM-IV/DSM-5 cannabis use disorder (CUD). Covariates included age, gender, race, total income, and study year. Separate weighted multivariable logistic regressions assessed associations between binge drinking and each cannabis outcome and provided adjusted prevalences of cannabis outcomes by binge drinking status. Past-month binge drinking was positively associated with past-month (OR: 3.72, 95 %CI: 3.56-3.93) and past-year (OR: 3.90, 95 %CI: 3.74-4.06) cannabis use in adjusted regressions. The adjusted odds of DSM-IV and DSM-5 CUD among people who used cannabis were 15 % and 12 % higher among people who engaged in binge drinking than those who did not, respectively (OR: 1.15, 95 %CI: 1.05, 1.26 and OR: 1.12, 95 %CI: 1.03, 1.21). Conversely, the odds of past-month daily cannabis use among people who used cannabis and reported binge drinking was 18 % lower than those who did not (OR: 0.82, 95 %CI: 0.74, 0.91). Our findings provide evidence of associations between binge drinking and cannabis use. Future studies should explore associations between cannabis and other alcohol use behaviors, including heavy drinking, and simultaneous alcohol and cannabis use.

The Green Sheep: Exploring the Perceived Risks and Benefits of Cannabis Among Young Military Members and Veterans

Medical and recreational cannabis are becoming more accessible and socially accepted across the United States. Emerging adults (EAs; 18 to 29) are the largest group of cannabis users. Studies have found that veterans are more likely to report cannabis use compared to nonveterans. While research exists on the use levels of cannabis, limited knowledge is available on the perceived risks and benefits of using cannabis among EA military and veteran populations. Helping professionals encounter veterans who use cannabis and must consider military cultural factors and attitudes towards cannabis that may influence or exacerbate cannabis use. We conducted a qualitative study with 23 EA veteran and military members with high-risk substance use and asked about their thoughts on the acceptability, risks, and perceived benefits associated with cannabis. Two qualitative coders used NVivo to find themes following the six steps of thematic analysis. Results provide in-depth understanding of EA military members and veterans' perceptions of cannabis. Overall, we found participants were receptive to using cannabis for pain ailments, mental health issues, and as an alternative to benzodiazepines, opioids, and alcohol. However, they acknowledged restrictions are needed to moderate cannabis use and mitigate negative outcomes. Lastly, participants recognized the incongruence of cannabis use with military job responsibilities and expectations. These findings shed light on potential risk and protective factors related to using cannabis for recreational or medical reasons and should be considered when consulting EA military members and veterans.

Emergency Department Pediatric Visits in Alberta for Cannabis After Legalization

BACKGROUND AND OBJECTIVES

Canada legalized nonmedical cannabis possession and sale in October 2018. In the United States, state legalization has been tied to an increase in cannabis-related emergency department (ED) visits; however, little research exists on provincial changes in pediatric visits after nationwide legislation. We compared pre- and postlegalization trends in pediatric cannabis-related ED visits and presentation patterns in urban Alberta EDs.

METHODS

Retrospective National Ambulatory Care Reporting System data were queried for urban Alberta cannabis-related ED visits among patients aged <18 years from October 1, 2013, to February 29, 2020. Population subgroups included children (aged 0-11 years), younger adolescents (12 to 14 years), and older adolescents (15 to 17 years). We calculated interrupted time series, incident rate ratios (IRRs), and relative risk (RR) ratios to identify trend change. IRRs identified changes against growth-adjusted Alberta population, while RRs measured presentation pattern changes against prelegalization ED visits.

RESULTS

Pediatric visit volume did not change postlegalization when accounting for preexisting volume trends. Unintentional ingestions increased in children (IRR: 1.77, 95% confidence interval [CI]: 1.42 to 2.20 and RR: 1.24, 95% CI: 1.05 to 1.47, respectively) and older adolescents (IRR: 1.36, 95% CI: 1.07 to 1.71 and RR: 1.48, 95% CI: 1.21 to 1.81, respectively). Presentation patterns remained similar, although older adolescent co-ingestant use decreased (RR: 0.77, 95% CI: 0.67 to 0.88), whereas hyperemesis cases increased (RR: 1.64, 95% CI: 1.13 to 2.37).

CONCLUSIONS

Cannabis legalization has increased child and older adolescent unintentional cannabis ingestions, increasing child cannabis-related ED visits. Changes highlight need for public health interventions targeting pediatric exposures.

Cannabis use disorder among atrial fibrillation admissions, 2008-2018

BACKGROUND

Despite changes inthe legality of cannabis use and the increasing prevalence of cannabis use disorder (CUD), there is little data investigating the association between CUD and inpatient atrial fibrillation (AF) hospitalizations.

METHODS

Using the National Inpatient Sample, we identified Atrial Fibrillation (AF) hospitalizations with and without a codiagnosis of CUD using International Classification of Diseases diagnosis codes and compared demographics, socioeconomics, comorbidities, outcomes, and trends between cohorts.

RESULTS

Between 2008 and 2018, we identified 5,155,789 admissions for AF of which 31,768 (0.6%) had a codiagnosis of CUD. The proportion of admissions with a history of CUD increased from 0.3% in 2008 to 1.0% in 2018 (p < .001). Hospital discharges of patients with CUD were significantly younger (53 vs. 72 years, p < .001), had a higher proportion of black race (CUD: 26.6% vs. 8.0%, p < .001), and had a higher proportion of income in the lowest income quartile than without a codiagnosis of CUD (CUD: 40.5% vs. 26.2%, p < .001).

CONCLUSIONS

CUD is increasingly prevalent among AF hospitalizations, particularly among young patients. Codiagnosis of CUD in AF hospitalizations is also more common in underserved patients. As a result, it is important for future research to examine and understand the impact of CUD on this population, particularly in the light of changing legislation surrounding the legality of cannabis.

The chemistry and toxicology of vaping

Vaping is the process of inhaling and exhaling an aerosol produced by an e-cigarette, vape pen, or personal aerosolizer. When the device contains nicotine, the Food and Drug Administration (FDA) lists the product as an electronic nicotine delivery system or ENDS device. Similar electronic devices can be used to vape cannabis extracts. Over the past decade, the vaping market has increased exponentially, raising health concerns over the number of people exposed and a nationwide outbreak of cases of severe, sometimes fatal, lung dysfunction that arose suddenly in otherwise healthy individuals. In this review, we discuss the various vaping technologies, which are remarkably diverse, and summarize the use prevalence in the U.S. over time by youths and adults. We examine the complex chemistry of vape carrier solvents, flavoring chemicals, and transformation products. We review the health effects from epidemiological and laboratory studies and, finally, discuss the proposed mechanisms underlying some of these health effects. We conclude that since much of the research in this area is recent and vaping technologies are dynamic, our understanding of the health effects is insufficient. With the rapid growth of ENDS use, consumers and regulatory bodies need a better understanding of constituent-dependent toxicity to guide product use and regulatory decisions.

Differences in child and adult biopsychosocial characteristics associated with regular cannabis use in individuals with and without cannabis use disorder

BACKGROUND

Regular cannabis use, even without cannabis use disorder (CUD), is associated with numerous biopsychosocial problems. Biopsychosocial risk factors that precede regular use and CUD might reflect broader pre-existing risk factors rather than the consequence of cannabis use. We aimed to (1) replicate prior work differentiating psychosocial problems associated with regular cannabis use with or without CUD relative to no-use in adulthood, and (2) test if these use groups differed in biopsychosocial functioning in early and middle childhood.

METHODS

Biopsychosocial characteristics of individuals at-risk for substance use problems (n = 402) reporting no-use, regular use without CUD, and regular use with CUD by young adulthood were prospectively compared during early childhood (ages 3-5), middle childhood (ages 9-11) and young adulthood (ages 18-25).

RESULTS

Regular use (vs. no-use) was associated with more health problems (mean d = |0.57|), psychopathology (mean d = |0.72|), social and family environment risk (mean d = |0.88|) in childhood and adulthood and comorbid substance use in adulthood (mean d = |1.25|). Regular use with and without CUD was linked to similar, developmentally-persistent patterns of problems across domains.

CONCLUSIONS

We found that childhood risk factors present many years prior to cannabis initiation (as early as age 3) differentiated patterns of adult cannabis use and CUD status in adulthood. Therefore, biopsychosocial impairments associated with regular cannabis use in adulthood is not solely attributable to cannabis exposure but can be traced back to early and persistent biopsychosocial risk that may benefit from early behavioral intervention, irrespective of CUD diagnosis.

Evidence for an increase in cannabis use in Iran - A systematic review and trend analysis

BACKGROUND AND AIMS

Cannabis is the most widely used illicit substance globally. In this systematic review, we examined the prevalence and trends of cannabis use and cannabis use disorder in Iran.

METHODS

We searched International and Iranian databases up to March 2021. Pooled prevalence of use among sex subgroups of the general population, university and high school students, combined youth groups, and high-risk groups was estimated through random-effects model. Trends of various use indicators and national seizures were examined.

RESULTS

Ninety studies were included. The prevalence estimates of last 12-month cannabis use were 1.3% (95%CI: 0.1-3.6) and 0.2% (95%CI: 0.1-0.3) among the male and female Iranian general population, respectively. The prevalence of cannabis use disorder among general population in national studies rose from 0% in 2001 to 0.5% in 2011. In the 2016-2020 period, the pooled prevalence estimates of last 12-month cannabis use were 4.9% (95% CI: 3.4-6.7) and 0.3% (95% CI: 0.0-1.3) among males and females of "combined youth groups", respectively. The linear trend of last 12-month cannabis use among males of "combined youth groups" and among female university students increased significantly from 2000 to 2020.

CONCLUSIONS

Prevalence of cannabis use in Iran is low compared to many countries. However, there is strong evidence of an increase in cannabis use among the youth and some evidence for an increase in cannabis use disorder.

Receipt of preventive health services and current cannabis users

Substance use is associated with greater barriers and reduced access to care. Little research, however, has examined the relationship between cannabis use and receipt of preventive health services. Using data from the 2017 Behavioral Risk Factor Surveillance System, we examined the association between current cannabis use and receipt of 12 preventive health services, adjusting for sociodemographic characteristics and access to care. In analyses that adjusted for sociodemographic factors and access to care, participants with current cannabis use had lower odds of being vaccinated for influenza (AOR = 0.67, 95% CI = 0.54-0.83) and higher odds of ever receiving HPV vaccination (AOR = 1.77, 95% CI = 1.06-2.96) and HIV screening (AOR = 2.34, 95% CI = 1.88-2.92) compared with those without cannabis use. Among the 12 preventive services examined, we found three differences in receipt of preventive services by cannabis use status. Cannabis use does not appear to be associated with significant underuse of preventive services.

The Impact of Closeness to Non-Parental Adults in Social Networks on Substance Use among Young Men Who Have Sex with Men

Non-parental adults (NPAs), or adults in social networks other than parents and romantic/sexual partnersare an under-examined potential resource in the lives of young men who have sex with men (YMSM). Using survey and social network data from a sample (n = 169) of ethnically diverse YMSM in a Midwestern city, this article examines longitudinal associations between emotional closeness to NPAs and subsequent substance use among YMSM. After controlling for race/ethnicity, closer relationships with NPAs were associated with a lower likelihood of binge-drinking and marijuana use six months later. In an exploratory set of analyses, the level of connectedness between NPAs and other members of social networks was not associated with substance use. Future studies should continue to examine the protective role of NPAs for both substance use and other health behaviors among YMSM.

Long-Term Consequences of Adolescent Exposure to THC-Rich/CBD-Poor and CBD-Rich/THC-Poor Combinations: A Comparison with Pure THC Treatment in Female Rats

Cannabis is the most-used recreational drug worldwide, with a high prevalence of use among adolescents. In animal models, long-term adverse effects were reported following chronic adolescent exposure to the main psychotomimetic component of the plant, delta-9-tetrahydrocannabinol (THC). However, these studies investigated the effects of pure THC, without taking into account other cannabinoids present in the cannabis plant. Interestingly, cannabidiol (CBD) content seems to mitigate some of the side effects of THC, at least in adult animals. Thus, in female rats, we evaluated the long-term consequences of a co-administration of THC and CBD at a 3:1 ratio, chosen based on the analysis of recently confiscated illegal cannabis samples in Europe. CBD content is able to mitigate some of the long-term behavioral alterations induced by adolescent THC exposure as well as long-term changes in CB1 receptor and microglia activation in the prefrontal cortex (PFC). We also investigated, for the first time, possible long-term effects of chronic administration of a THC/CBD combination reminiscent of "light cannabis" (CBD:THC in a 33:1 ratio; total THC 0.3%). Repeated administration of this CBD:THC combination has long-term adverse effects on cognition and leads to anhedonia. Concomitantly, it boosts Glutamic Acid Decarboxylase-67 (GAD67) levels in the PFC, suggesting a possible lasting effect on GABAergic neurotransmission.

The Potential Impact of Legalization of Recreational Cannabis among Current Users: A Qualitative Inquiry

Given legislative initiatives in Rhode Island pertaining to consideration of cannabis legalization for recreational purpose, a qualitative inquiry was conducted regarding anticipated changes in use among recreational cannabis users in Rhode Island. Five focus groups were conducted with recreational cannabis users (N = 31; 6-7 per group). Participants were queried about anticipated impact of legalization on their use patterns. Themes were identified using applied thematic analysis. Participants discussed (1) a desire to maintain the status quo due to satisfaction with local cannabis regulations and their current use behaviors, (2) how and why cannabis use may change, including pros and cons of legalization, and (3) anticipated changes in purchasing behavior given display and legitimacy of legal dispensaries. While participants anticipate use levels and prevalence may remain relatively stable following legislation changes, findings suggest possible changes related to mode of administration and location of use. Public health concerns exist related to high-risk potencies and use of cannabis in edible form; therefore, trialing of new cannabis products has important clinical implications should legalization occur in Rhode Island.

Framework for the Design of Cannabis-Mediated Phase I Drug-Drug Interaction Studies

Cannabis has become legal in much of the United States similarly to many other countries, for either recreational or medical use. The use of cannabis products is rapidly increasing while the body of knowledge of its myriad of effects still lags. In vitro and clinical data show that cannabis' main constituents, delta-9-tetrahydrocannabinol and cannabidiol, can affect the pharmacokinetics (PK), safety and pharmacodynamics (PD) of other drugs. Within the context of clinical drug development, the widespread and frequent use of cannabis products has essentially created another special population; that is, the cannabis user. We propose that all clinical drug development programs include a Phase 1 study to assess the drug-drug interaction potential of cannabis as a precipitant on the PK, safety and if applicable, the PD of all new molecular entities (NMEs) in a combination of healthy adult subjects as well as frequent and infrequent cannabis users. This data should be required to inform drug labeling and aid health care providers in treating any patient, as cannabis has quickly become another common concomitant medication and cannabis users, a new special population.

Marijuana Use during Pregnancy and Lactation and Long-term Outcomes

Recent surveys have shown increased use of marijuana during the perinatal period, possibly linked to increased legalization in many countries. Available information on the association between marijuana exposure and the effects on growth and development, as well as brain structure and function of the fetus, is growing but has not been uniform. Interpretation of these data is often challenging because of the influence of confounding factors and the sociodemographic variabilities in the study subjects. In this review, we present a synthesis of current information on the epidemiology and effects of marijuana use during pregnancy and evaluate the evidence for the immediate and long-term effects on affected neonates. We also describe the current knowledge and implications of breastfeeding and marijuana use and summarize selected current references about this practice. Finally, we provide the rationale for additional biological and population-based investigations to determine the various fetal outcomes of in-utero marijuana exposure that may assist in the establishment of prevention measures and applicable public health policies in the future.

Cannabis use and misuse in the year following recreational cannabis legalization in Canada: A longitudinal observational cohort study of community adults in Ontario

BACKGROUND

Canada legalized cannabis for non-medical purposes federally in October 2018. This study examined changes in cannabis use over the following year in a sample of general community adults. A secondary aim was to examine forecasted cannabis use following legalization in relation to actual post-legalization cannabis use.

METHODS

Participants were 1502 community adults (61 % female; age M = 34.60 ± 13.95), with approximately half reporting any cannabis use in the six months prior to legalization (Cannabis+ group [48 %]/Cannabis- group [52 %]). Self-report assessments were conducted in the month before cannabis legalization, 6-months post-legalization and 12-months post-legalization. Primary outcomes were frequency of cannabis use, grams of dried flower cannabis on days used, and level of misuse (Cannabis Use Disorder Identification Test - Revised). Secondary analyses examined pre-legalization personal forecasts in relation to post-legalization cannabis use.

RESULTS

Statistically significant main effects of time (ps<.001), cannabis use status (ps<.001), and time × cannabis use status interactions (ps<.001) were present for cannabis frequency, quantity, and level of misuse. In each case, the interactions reflected significant decreases in the Cannabis+ group, but significant increases in the Cannabis- group. Approximately 15 % of participants erroneously forecasted their personal post-legalization cannabis use, with discrepancies most commonly being individuals who were not using prior to legalization subsequently using cannabis.

CONCLUSIONS

In this cohort of community adults, we observed significant changes over the first year following Canadian legalization, with divergent trajectories based on pre-legalization cannabis use. These findings suggest multifarious impacts of legalization in adults, with meaningfully different trajectories among subgroups.

Cognitive and affective responses to marijuana prevention and educational messaging

BACKGROUND

Perceptions of risk of using marijuana have decreased significantly in the US over the last decade, while marijuana use has increased. In order to educate people on the risks associated with marijuana use, large-scale health messaging campaigns have been deployed to educate the public about the risks associated with marijuana use, particularly in states where medical or recreational marijuana is legal. Few studies have examined how messages about marijuana affect the audiences' cognitive and emotional responsivity to these messages.

METHODS

To address this knowledge gap, this study used psychophysiological assessment (heart rate, skin conductance, facial action coding) and self-report measures to explore the impact of different marijuana risk messages on real-time cognitive and affective responses and self-reported message receptivity, likeability, and intentions to use marijuana in a sample of 50 young adult marijuana users and non-users. Each participant saw six messages. Three messages were used from each of two campaigns, representing one of three risks (cognitive ability, driving, health harms).

RESULTS

Psychophysiological responses showed that the driving-themed messages for both campaigns had the greatest cognitive resource allocation to encoding the message, the greatest arousal, and the most positive emotional response, regardless of user status. Self-reports showed a less consistent pattern.

CONCLUSIONS

Overall, psychophysiological measures provided a more consistent picture of message processing and effects than self-report measures. Findings from this study provide immediately useful data for improving the development and effectiveness of marijuana health-risk prevention campaigns by elucidating cognitive and emotional processes that could be targeted in future programs.

Relations between impulsive personality traits, alcohol and cannabis co-use, and negative alcohol consequences: A test of cognitive and behavioral mediators

OBJECTIVE

Alcohol and cannabis co-users experience more negative alcohol consequences, but distal and mediating mechanisms of this association remain largely unstudied. Considering research suggests that individuals high in impulsivity and sensation seeking are more likely to be co-users, it is possible that co-users have more positive expectancies and become heavier drinkers, which confer risk for future negative consequences. Therefore, the current study tested prospective mediation models in which impulsive personality traits indirectly predicted negative consequences through co-use, heavier drinking, and expectancies.

METHODS

The current study used data from a study of familial AUD spanning 3 waves (1995-2010). Participants (N = 567) reported on impulsivity (via the Eysenck Personality Inventory and Sensation Seeking Scale) alcohol and cannabis use, alcohol expectancies, and negative consequences. Models tested the factor structure of impulsive personality traits and whether these traits predicted future negative consequences through past-year co-use and drinking/expectancies.

RESULTS

Factor analysis suggested two factors, sensation seeking and lack of premeditation. Sensation seeking was associated with future negative consequences indirectly through co-use and both drinking quantity and positive expectancies. Lack of premeditation was not associated with co-use, but indirectly predicted negative consequences through positive expectancies, above and beyond co-use. Sensation seeking directly predicted negative expectancies, but negative expectancies did not predict negative consequences.

CONCLUSIONS

Impulsive personality traits in co-users, particularly sensation seeking, explained variance in future negative alcohol consequences via heavier drinking (behavior) and positive expectancies (cognition). Personalized interventions targeting a lack of premeditation, and sensation seeking in co-users, may interrupt a developmental trajectory toward problem drinking.

The Impact of THC and CBD in Schizophrenia: A Systematic Review

Background: People with schizophrenia are more likely to develop cannabis use disorder (CUD) and experience worse outcomes with use. Yet as cannabis is legalized for medical and recreational use, there is interest in its therapeutic potential. Objectives: To conduct a systematic review summarizing the design and results of controlled trials using defined doses of THC and CBD in schizophrenia. Method: A keyword search of eight online literature databases identified 11 eligible reports. Results: One placebo controlled trial (13 stable patients without CUD) found that intravenous THC increased psychosis and worsened learning/recall. Two reports of a functional magnetic resonance (fMRI) study of smoked or oral THC in 12 abstinent patients with schizophrenia and CUD found no change in symptoms and cognition, and an amelioration of impaired resting state brain function in areas implicated in reward function and the default mode network. One 4 week trial in acutely psychotic inpatients without CUD (mean age 30 y) found 800 mg CBD to be similarly efficacious to amisupride in improving psychosis and cognition. Two 6 week studies of CBD augmentation of antipsychotics in stable outpatients reported mixed results: CBD 600 mg was not more effective than placebo; CBD 1,000 mg reduced symptoms in a sample that did not exclude cannabis use and CUD. A brain fMRI and proton magnetic resonance spectroscopy study of single dose CBD in a sample that did not exclude CUD and cannabis use found that CBD improved symptoms and brain function during a learning/recall task and was associated with increased hippocampal glutamate. Discussion: There is substantial heterogeneity across studies in dose, method of drug delivery, length of treatment, patient age, whether patients with cannabis use/CUD were included or excluded, and whether patients were using antipsychotic medication. Conclusion: There is insufficient evidence for an effect of THC or CBD on symptoms, cognition, and neuroimaging measures of brain function in schizophrenia. At this time, research does not support recommending medical cannabis (THC or CBD) for treating patients with schizophrenia. Further research should examine THC and CBD in schizophrenia with and without comorbid CUD and consider the role of CBD in mitigating symptom exacerbation from THC.

Evaluating spin in the abstracts of systematic reviews and meta-analyses on cannabis use disorder

BACKGROUND

Clinicians rely upon abstracts to provide them quick synopses of research findings that may apply to their practice. Spin can exist within these abstracts that distorts or misrepresents the findings. Our goal was to evaluate the level of spin within systematic reviews (SRs) focused on the treatment of cannabis use disorder (CUD). Methods: A systematic search was conducted in May 2020. To meet inclusion criteria, publications had to be either an SR or meta-analysis related to the treatment of cannabis use. Screening and data extraction was performed in a duplicate and masked fashion. Study quality was assessed using AMSTAR-2 Results: 16/24 SRs (66.7%) contained at least one form of spin in the abstract. The most common forms of spin identified were type 3-selective reporting of or overemphasis on efficacy outcomes or analysis favoring the beneficial effect of the experimental intervention (45.8%)-and type 8-the review's findings from a surrogate marker or a specific outcome to the global improvement of the disease (37.5%). No significant association between spin and intervention type, PRISMA requirements, or funding source was identified. Weak positive correlations were found between the presence of spin and abstract word count (r =.217) and between spin and AMSTAR-2 rating (r = 0.143). "Moderate" was the most common AMSTAR-2 rating (9/24, 37.5%), followed by "low" (7/24, 29.2%) and "critically low" (7/24, 29.2%). One systematic review received an AMSTAR-2 rating of "high" (1/24, 4.2%). Conclusions: Spin was common among abstracts from the SRs focused on the treatments for CUD. Higher quality studies may help reduce the overall rate as well as standardizing treatment outcomes. To facilitate this, we encourage all authors, peer-reviewers, and editors to be more aware of the various types of spin as they can help reduce the overall amount of spin seen within the literature.

Repetitive transcranial magnetic stimulation as a potential treatment approach for cannabis use disorder

The expanding legalization of cannabis across the United States is associated with increases in cannabis use, and accordingly, an increase in the number and severity of individuals with cannabis use disorder (CUD). The lack of FDA-approved pharmacotherapies and modest efficacy of psychotherapeutic interventions means that many of those who seek treatment for CUD relapse within the first few months. Consequently, there is a pressing need for innovative, evidence-based treatment development for CUD. Preliminary evidence suggests that repetitive transcranial magnetic stimulation (rTMS) may be a novel, non-invasive therapeutic neuromodulation tool for the treatment of a variety of substance use disorders (SUDs), including recently receiving FDA clearance (August 2020) for use as a smoking cessation aid in tobacco cigarette smokers. However, the potential of rTMS for CUD has not yet been reviewed. This paper provides a primer on therapeutic neuromodulation techniques for SUDs, with a particular focus on reviewing the current status of rTMS research in people who use cannabis. Lastly, future directions are proposed for rTMS treatment development in CUD, with suggestions for study design parameters and clinical endpoints based on current gold-standard practices for therapeutic neuromodulation research.

The association between cannabis use disorder and the outcome following primary total hip arthroplasty : analysis of a nationwide administrative claims database

AIMS

Although there is increasing legalization of the use of cannabis in the USA, few well-powered studies have evaluated the association between cannabis use disorder and outcomes following primary total hip arthroplasty (THA). Thus, the aim of this study was to determine whether patients who use cannabis and undergo primary THA have higher rates of in-hospital length of stay (LOS), medical complications, implant-related complications, and costs.

METHODS

Using an administrative database, patients with cannabis use disorder undergoing primary THA were matched to a control group in a 1:5 ratio by age, sex, and various medical comorbidities. This yielded 23,030 patients (3,842 in the study group matched with 19,188 in the control group). The variables which were studied included LOS, 90-day medical complications, two-year implant-related complications, and 90-day costs of care. Mann-Whitney U tests were used to compare LOS and costs. Multivariate logistic regression analyses were used to calculate the odds ratios (ORs) of developing complications.

RESULTS

We found that patients in the study group had a significantly longer mean LOS compared with the controls (four days vs three days; p < 0.0001).The study group also had a significantly higher incidence and odds of developing medical (23.0 vs 9.8%, OR 1.6; p < 0.0001) and implant-related complications (16 vs 7.4%, OR 1.6; p < 0.0001) and incurred significantly higher mean 90-day costs ($16,938.00 vs $16,023.00; p < 0.0001).

CONCLUSION

With the increasing rates of cannabis use, these findings allow orthopaedic surgeons and other healthcare professionals to counsel patients with cannabis use disorder about the possible outcomes following their THA, with increased hospital stays, complications, and costs. Cite this article: Bone Joint J 2021;103-B(7 Supple B):111-115.

Time-trends in hospitalizations with cannabis use disorder: A 17-year U.S. national study

Objective: To assess whether cannabis use disorder (abuse or dependence) hospitalizations are increasing over time and examine the variables associated with the outcomes of cannabis use disorder hospitalizations. Methods: This study examined the rates of hospitalizations with cannabis use disorder and associated healthcare utilization using the U.S. National Inpatient Sample data from 1998 to 2014. Adjusted logistic regression analyses assessed the association of demographic, comorbidity and hospital characteristics with healthcare utilization (total hospital charges, length of hospital stays, discharge to a non-home setting) during the index hospitalization for cannabis use disorder. Odds ratio (OR) and 95% confidence intervals (CI) were calculated. Results: There were an estimated 5,601,382 hospitalizations with cannabis use disorder (primary or secondary diagnosis). The rates of hospitalization (/100,000 admissions) for cannabis use disorder increased 3.7-fold from 439/100,000 admissions in 1998-2000 to 1,631/100,000 admissions in 2013-2014. In the adjusted analysis, the following factors were associated with worse healthcare utilization outcomes for cannabis use disorder hospitalizations: older age; Deyo-Charlson index score of 2 or higher; male sex; insurance payer other than private; higher income; hospital region; an urban hospital; and a medium to large hospital bed size. Conclusions: Rising hospitalization rate with cannabis use disorder from 1998 to 2014 is concerning. Our study identified independent variables associated with a higher risk of poor utilization outcomes of cannabis use disorder hospitalizations. Healthcare policies should focus on reducing the burden of cannabis use disorder hospitalizations. High-risk groups of people with cannabis use disorder with the worst outcomes should be targeted to reduce associated utilization.

Responses to social evaluative stress in regular cannabis smokers

BACKGROUND

Aspects of the canonical stress response differ in stimulant, opioid, and alcohol users relative to controls, and dysregulated responses to stress may contribute to continued use of these drugs. Little prior research has focused on stress responses in regular cannabis smokers. We assessed responses to a standardized laboratory social stress assay (the Trier Social Stress Task; TSST) in regular cannabis smokers (CANs) compared with controls (CONs).

METHODS

Healthy, non-treatment-seeking adult CANs (⩾4×/week; smoking cannabis as usual) and demographically matched CONs completed the TSST. Outcome measures were subjective mood, heart rate, and salivary cortisol.

RESULTS

Nineteen CANs (1 female) and 20 CONs (2 female) participated; groups were matched on trauma exposure, sex, race, and age. CANs smoked cannabis 6.4 ± 1.1 days/week. Eight CANs and one CON smoked tobacco cigarettes daily. Overall, the TSST produced expected increases in anxiety, negative mood states, cortisol, and heart rate. CANs had blunted subjective response to stress relative to CONs, but they did not differ in physiological (cortisol and cardiovascular) stress responding.

CONCLUSION

These results indicate that CANs have blunted mood responses to social stress, but normative physiological stress responding. Observed differences could be due to residual effects of cannabis, reluctance to endorse negative mood states, or to issues related to identifying (i.e., emotional identification) or feeling (i.e., interoception) stress-related affective states. Further research is warranted to characterize the mechanisms of these differences and assess implications for daily functioning and treatment outcomes.