Systematic review of outcome domains and measures used in psychosocial and pharmacological treatment trials for cannabis use disorder

Examining Profiles and Treatment Outcomes in Dual Diagnosis: Comparison of Coordinated Treatment With Mental Health Services Versus Addiction Center Alone. A Real-World Data Analysis

OBJECTIVE

The aim of this work was to examine the profile and treatment outcomes of patients with dual pathology depending on whether the patients were attending addiction centers or are being treated in a coordinated model by mental health services.

METHODS

Data from 7225 dual diagnosis patients were used, of whom 2417 (33.5%) received treatment in the mental health coordinated modality. Clinical information was taken from the patients' electronic health record.

RESULTS

Differences were found in patients' sociodemographic and comorbidity profiles according to treatment modality. In general, coordinated care yielded favorable outcomes (higher attendance and lower dropout rates but no differences in retention). The logistic regression analysis identified predictors of patient profiles in coordinated care, emphasizing having a severe mental health disorder (OR = 3.878, 95% CI [3.443, 4.368]; p = .000), being referred by social/health services, or having retired status. Main differences were observed according to the comorbid diagnosis presented, particularly in cases in which the patient had impulse control, hyperkinetic, or cluster C personality disorder.

CONCLUSIONS

While therapeutic outcomes are influenced by associated comorbidities, the disorders prognosis can be favorable with appropriate treatment. Furthermore, analysis of differences according to treatment modality allows for predicting the type of patient who will receive a particular service, which enables the development of tailored treatments.

Typical Hits, Grams, or Joints: Evaluating Cannabis Survey Measurement Strategies for Quantifying Consumption

Aim: Standardized survey measures that capture diverse cannabis consumption patterns are needed to inform public health and policy. Our team is developing a flexible, personalized, low-burden survey item inventory to measure cannabis use patterns and estimate milligrams of THC (mgTHC) consumption in large samples. This study aimed to identify measurement gaps and analysis implications associated with an initial pool of candidate items that assessed use of cannabis flower and concentrate products (smoked and/or vaporized). Methods: Adult cannabis consumers (n=4247) completed an online survey assessing cannabis use frequency, quantity, product types, product potencies (%THC), and methods of administration. Participants chose to report their consumption quantities using one of three units: "hits per day," "grams per week," or "joints per week." Respondents also indicated whether their past 7-day consumption pattern represented their typical pattern. Results: Eighty-one percent had used cannabis daily in the past week. Thirty-two percent, 53%, and 15% chose to report flower and concentrate consumption quantity in hits, grams, and joints, respectively. Approximately 80-90% of responses for the number of hits, grams, and joints consumed were less than the maximum response option-suggesting that response options captured the full range of potential cannabis consumption behaviors. Those who chose grams or joints units were generally more likely to endorse higher risk cannabis use (e.g., morning use, high %THC products) in the past week than those who chose the hits unit (adjusted Odds Ratio range: 1.2-3.9). Among those who reported that the past week represented their typical behavior (83%), past 30-day and past 7-day frequencies were highly correlated (Spearman's Rho=0.77)-supporting the feasibility of using lower burden "typical week" items to extrapolate patterns beyond a 1-week time frame. Conclusion: Results from this online convenience sample of frequent cannabis consumers suggest that the current items yield coherent and expected response patterns. Although additional testing is required, a standardized, flexible survey instrument for large-scale assessment of cannabis patterns and calculation of mgTHC seems within reach.

Associations between cannabis policies and state-level specialty cannabis use disorder treatment in the United States, 2004-2019

BACKGROUND

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.

METHODS

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).

RESULTS

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.

CONCLUSIONS

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.

Assessing Cannabis Use in People with Psychosis

Introduction: Cannabis use is common in people with psychotic disorders and is associated with the exacerbation of symptoms, poor treatment adherence, and an increased risk of relapse. Accurate assessment of cannabis use is thus critical to the clinical management of psychosis. Discussion: Cannabis use is usually assessed with self-report questionnaires that were originally developed for healthy individuals or people with a cannabis use disorder. Compared to these groups, the pattern of cannabis use and the associated harms in patients with psychosis are quite different. Moreover, in people with psychosis, the accuracy of self-reported use may be impaired by psychotic symptoms, cognitive deficits, and a desire to conceal use when clinicians have advised against it. Although urinary screening for delta-9-tetrahydrocannabinol is sometimes used in the assessment of acute psychotic episodes, it is not used in routinely. Cannabis use could be assessed by measuring the concentration of cannabinoids in urine and blood, but this is rarely done in either clinical settings or research. Conclusion: Using quantitative biological measures could provide a more accurate guide to the effects of use on the disorder than asking patients or using questionnaires.

Exploring survey methods for measuring consumption quantities of cannabis flower and concentrate products

Background: Researchers need accurate measurements of cannabis consumption quantities to assess risks and benefits. Survey methods for measuring cannabis flower and concentrate quantities remain underdeveloped.Objective: We examined "grams" and "hits" units for measuring flower and concentrate quantities, and calculating milligrams of THC (mgTHC).Methods: Online survey participants (n = 2,381) reported preferred unit (hits or grams), past-week hits and grams for each product, and product %THC. Quantile regression compared mgTHC between unit-preference subgroups. Hits-based mgTHC calculations assumed a universal grams-per-hit ratio (GPHR). To examine individualized GPHRs, we tested a "two-item approach," which divided total grams by total hits, and "one-item approach," which divided 0.5 grams by responses to the question: "How many total hits would it take you to finish 1/2 g of your [product] by [administration method]?"Results: Participants were primarily daily consumers (77%), 50% female sex, mean age 39.0 (SD 16.4), 85% White, 49% employed full-time. Compared to those who preferred the hits unit, those who preferred the grams unit reported consuming more hits and grams, higher %THC products, and consequently, larger median mgTHC (flower-hits mgTHC: 32 vs. 91 (95%CI: 52-67); flower-grams mgTHC: 27 vs. 113 (95%CI: 73-95); concentrate-hits mgTHC: 29 vs. 59 (95%CI: 15-43); concentrate-grams mgTHC: 61 vs. 129 (95%CI: 43-94)). "Two-item" and "one-item" approach GPHRs were similar and frequently 50% larger or smaller than the universal GPHR.Conclusion: Allowing respondents to choose "hits" or "grams" when reporting cannabis quantities does not compromise mgTHC estimates. A low-burden, one-item approach yields individualized "hit sizes" that may improve mgTHC estimates.

Implementation and Preliminary Evaluation of a 12-Week Cognitive Behavioural and Motivational Enhancement Group Therapy for Cannabis Use Disorder

Background

The purpose of this paper is to provide a preliminary evaluation of treatment outcomes, retention and client satisfaction following a 12-week combined cognitive behavioural therapy (CBT) and motivational enhancement therapy (MET) group treatment for cannabis use disorder (CUD) delivered in an outpatient setting. Implementation of the program is also described.

Methods

A retrospective observational cohort study was conducted using data collected from medical records and self-report assessments. Participants were treatment-seeking cannabis users at the Centre for Addiction and Mental Health, Toronto. Cannabis use, cannabis-related problems, craving, withdrawal symptoms, self-efficacy for remaining abstinent, depression and anxiety were assessed pre- and post-treatment. Treatment retention was calculated by inspecting clinic attendance records, and client satisfaction was evaluated using an anonymous feedback survey. Potential predictors of treatment outcomes and retention were investigated in exploratory analyses.

Results

Cannabis use was lower and days of abstinence higher post-treatment (vs pre-treatment). Post-treatment improvements in cannabis-related problems, craving, withdrawal symptoms, self-efficacy and mood were also observed. Completion of group treatment (⩾75% of sessions attended) was 57% and moderate levels of treatment satisfaction were reported.

Conclusions

This study provides preliminary evidence that a 12-week combined CBT and MET treatment for cannabis use disorder delivered in a novel group setting improves cannabis use outcomes. Potential predictors of reduced cannabis use and retention were identified. Future controlled studies are warranted, and strategies for increasing retention should be explored.

Is it time for a cannabis harm reduction approach? Commentary on Sherman et al. (2022) and Borodovsky et al. (2022)

OBJECTIVE

Recent research suggests potential therapeutic benefits of cannabis-derived products, a lower risk profile than other illicit substances, and significant functional improvement from reduced use. Likewise, low abstinence rates and low motivation to achieve abstinence among those with cannabis use disorder (CUD) are the norm. As such, the harm reduction model has gained traction among substance use scientists and health care professionals as a viable alternative approach. Yet, to date no formal definition of cannabis harm reduction has been proposed.

METHOD

We reviewed the literature, including two recent empirical papers published in the Psychology of Addictive Behaviors, Sherman et al. (2022) and Borodovsky et al. (2022), which demonstrate that harm reduction is sufficient to achieve functional improvement. We then propose and define a harm reduction approach for cannabis use research and treatment, and argue why this approach is a timely, necessary discussion.

RESULTS

We suggest that a cannabis harm reduction approach includes treatment, research, and education initiatives that reduce the public health burden of cannabis use. This approach includes interventions that reduce functional impairment and risk from cannabis, reduced or managed use, and sometimes, but not necessarily, abstinence. Psychoeducation for treatment providers, legislative barriers, and research recommendations are also discussed.

CONCLUSIONS

Research and treatment for CUD has historically focused on cannabis abstinence. Treatment trials rarely yield durable abstinence rates, and reduction has recently been tied to functional improvement. We comment on Sherman et al. (2022) and Borodovsky et al. (2022) and propose a shift toward a cannabis harm reduction approach. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Evaluating cannabis exposure in survey items: Insights, strategies, and remaining challenges identified from cognitive interviewing

Background

The diversity in characteristics of cannabis products and behavior patterns make evaluation of cannabis exposure in population-based, self-report surveys challenging. Accurate identification of cannabis exposure and related outcomes necessitates a thorough understanding of participants' interpretations of survey questions assessing cannabis consumption behaviors.

Objectives

The current study utilized cognitive interviewing to gain insight on participants' interpretation of items in a self-reported survey instrument used to estimate the quantity of THC consumed in population samples.

Methods

Cognitive interviewing was used to evaluate survey items assessing cannabis use frequency, routes of administration, quantity, potency, and perceived "typical patterns" of use. Ten participants ≥18 years (n = 4 cisgender-men; n = 3 cisgender-women; n = 3 non-binary/transgender) who had used cannabis plant material or concentrates in the past week were recruited to take a self-administered questionnaire and subsequently answer a series of scripted probes regarding survey items.

Results

While most items presented no issues with comprehension, participants identified several areas of ambiguity in question or response item wording or in visual cues included in the survey. Generally, participants with irregular use patterns (i.e., non-daily use) reported more difficulty recalling the time or quantity of cannabis use. Findings resulted in several changes to the updated survey, including updated reference images and new quantity/frequency of use items specific to the route of administration.

Conclusion

Incorporating cognitive interviewing into cannabis measurement development among a sample of knowledgeable cannabis consumers led to improvements in assessing cannabis exposure in population surveys, which may otherwise have been missed.

Scoping Review of Cannabis-Reduction Psychosocial Interventions and Reasons for Use among Young Adults with Psychosis

Objective: No evidence-based intervention effectively reduces cannabis use in young adults with psychosis (YAP). To generate hypotheses about why, a scoping review was conducted to synthesize evidence about motivations for cannabis use and reduction/cessation for YAP and the psychosocial interventions trialed to identify possible gaps between motivations and interventive strategies. Methods: A systematic literature search was conducted in December, 2022. Reviews of titles and abstracts (N = 3,216) and full-texts (n = 136) resulted in 46 articles. Results: YAP use cannabis for pleasure, to reduce dysphoria, and for social and recreational reasons; motivations for cessation include insight about cannabis-psychosis interactions, incompatibility with goals and social roles, and support from social networks. Interventions with at least minimal evidence of efficacy include motivational interviewing, cognitive-behavioral strategies, and family skills training. Conclusions: Authors recommend additional research on mechanisms of change and motivational enhancement therapy, behavioral activation, and family-based skills interventions matched to YAP motivations for use/cessation.

Monitoring adherence and abstinence of cannabis use disorder patients: Profile identification and relationship with long-term treatment outcomes

BACKGROUND

Patients with cannabis use disorder (CUD) show heterogeneous sociodemographic and consumption patterns. Although previous studies, focused on identifying subgroups of CUD patients using input variables, have yielded useful results for planning individualized treatments, no published research has analyzed the profiles of CUD patients according to their therapeutic progress. This study therefore aims to identify subgroups of patients using adherence and abstinence indicators and to explore whether these profiles are associated with sociodemographic characteristics, consumption variables, and long-term therapeutic outcomes.

METHODS

This was a retrospective observational study with a multisite sample of 2055 CUD outpatients who were beginning treatment. The study monitored patient data at two-year follow-up. We conducted latent profiles analysis on the appointment attendance ratio and percentage of negative cannabis tests.

RESULTS

A three profile solution emerged: i) moderate abstinence/moderate adherence (n = 997); ii) high abstinence/moderate adherence (n = 613); and iii) high abstinence/high adherence (n = 445). The study found the most marked differences at the beginning of treatment for education level (chi² (8) = 121.70, p < .001), source of referral (chi² (12) = 203.55, p < .001), and frequency of cannabis use (chi² (10) = 232.39, p < .001). Eighty percent of patients from the "high abstinence/high adherence" group were relapse-free at two year follow-up. This percentage decreased to 24.3 % in the "moderate abstinence/moderate adherence" group.

CONCLUSIONS

Research has shown adherence and abstinence indicators to be useful for identifying subgroups of patients with different prognoses regarding long-term success. Recognizing the sociodemographic and consumption variables associated with these profiles at the beginning of treatment could help to inform the design of more individualized interventions.

Anxiety sensitivity and cigarette use on cannabis use problems, perceived barriers for cannabis cessation, and self-efficacy for quitting among adults with cannabis use disorder

Many individuals diagnosed with cannabis use disorder (CUD) report a desire to quit using cannabis due to problems associated with use. Yet, successful abstinence is difficult for a large subset of this population. Thus, the present study sought to elucidate potential risk factors for cannabis use problems, perceived barriers for quitting, and diminished self-efficacy for remaining abstinent. Specifically, this investigation examined cigarette user status, anxiety sensitivity, and the interplay between these individual difference factors in terms of cannabis-related problems, perceived barriers for cannabis cessation, and self-efficacy for quitting cannabis use. The sample consisted of 132 adult cannabis users who met criteria for CUD and were interested in quitting (38 % female; 63.6 % Black; Mage = 37.22; SDage = 28.79; 54.6 % current tobacco users). Findings revealed a significant interaction, such that anxiety sensitivity was related to cannabis use problems and perceived barriers for cannabis cessation among current cigarette users, but not among cigarette non-users. There was no significant interaction for self-efficacy for remaining abstinent. The current findings suggest that cigarette users constitute a subgroup that may be especially vulnerable to the effects of anxiety sensitivity in terms of cannabis use problems and perceived barriers for quitting cannabis use.

Using ecological momentary assessment and a portable device to quantify standard tetrahydrocannabinol units for cannabis flower smoking

AIMS

To evaluate the feasibility and validity of a new method of quantifying cannabis flower use, integrating the amount of cannabis flower smoked, and the potency of the cannabis flower.

DESIGN

Ecological momentary assessment (EMA) for 14 days.

SETTING

Participants' daily lives in Columbia, Missouri, USA.

PARTICIPANTS

A total of 50 community participants, who were regular cannabis flower smokers (48% female).

MEASUREMENTS

Momentary subjective intoxication ratings following cannabis flower smoking; momentary quantity of cannabis flower smoked; potency of cannabis flower smoked in terms of percentage of tetrahydrocannabinol (THC) concentration assessed with a portable device, the Purpl Pro; and time since finished smoking.

FINDINGS

Participants completed our field testing of their cannabis flower (96.2%) and were compliant with our 2-week EMA protocol (73% for random prompts and 91% for morning reports). Momentary subjective intoxication ratings trended down as a function of time since smoking (r = -0.10, P = 0.004, 95% CI, [-0.17, -0.03]). Multi-level model (MLM) results indicated the momentary standard THC units (mg THC) were positively associated with momentary subjective intoxication ratings (b = 0.01, P = 0.03, 95% CI, [0.01, 0.012]).

CONCLUSIONS

There is evidence to support the feasibility and initial validity of a new method of quantifying cannabis flower use into standard tetrahydrocannabinol units. Researchers investigating the effects of cannabis flower use on a range of outcomes (e.g. neurobehavioral effects, emotional sequelae, and driving impairment) as well as in clinical treatment trials might adopt this method to provide estimates of cannabis flower use.

Cannabinoids and solid organ transplantation: Psychiatric perspectives and recommendations

Cannabinoid use in patients seeking solid organ transplantation (SOT) is an important and unsettled matter which all transplantation clinicians regularly encounter. It is also a multifaceted, interprofessional issue, difficult for any specialty alone to adequately address in a research article or during clinical care. Such uncertainty lends itself to bias for or against cannabinoid use accompanied by inconsistent policies and procedures. Scientific literature in SOT regarding cannabinoids often narrowly examines the issue and exists mostly in liver and kidney transplantation. Published recommendations from professional societies are mosaics of vagueness and specificity mirroring the ongoing dilemma. The cannabinoid information SOT clinicians need for clinical care may require data and perspectives from diverse medical literature which are rarely synthesized. SOT teams may not be adequately staffed or trained to address various neuropsychiatric cannabinoid effects and risks in patients. In this article, authors from US transplantation centers conduct a systematized review of the few existing studies regarding clinician perceptions, use rates, and clinical impact of cannabinoid use in SOT patients; collate representative professional society guidance on the topic; draw from diverse medical literature bases to detail facets of cannabinoid use in psychiatry and addiction pertinent to all transplantation clinicians; provide basic clinical and policy recommendations; and indicate areas of future study.

Mood, sleep and pain comorbidity outcomes in cannabis dependent patients: Findings from a nabiximols versus placebo randomised controlled trial

BACKGROUND

Mood, sleep and pain problems are common comorbidities among treatment-seeking cannabis-dependent patients. There is limited evidence suggesting treatment for cannabis dependence is associated with their improvement. This study explored the impact of cannabis dependence treatment on these comorbidities.

METHODS

This is a secondary analysis from a 12-week double-blind placebo-controlled trial testing the efficacy of a cannabis agonist (nabiximols) against placebo in reducing illicit cannabis use in 128 cannabis-dependent participants. Outcome measurements including DASS-21 (Depression, Anxiety, and Stress subscales); Insomnia Severity Index (ISI); and Brief Pain Inventory (BPI), were performed at weeks 0, 4, 8, 12 and 24. Each was analysed as continuous outcomes and as binary cases based on validated clinical cut-offs.

RESULTS

Among those whose DASS and ISI scores were in the moderate to severe range at baseline, after controlling for cannabis use, there was a gradual decrease in severity of symptoms over the course of the trial. BPI decreased significantly until week 12 and then rose again in the post-treatment period during weeks 12-24. Neither pharmacotherapy type (nabiximols vs placebo) nor number of counselling sessions contributed significant explanatory power to any of the models and were excluded from the final analyses for both continuous and categorical outcomes.

CONCLUSIONS

Participants in this trial who qualified as cases at baseline had elevated comorbidity symptoms. There was no evidence that nabiximols treatment is a barrier to achieving reductions in the comorbid symptoms examined. Cannabis dependence treatment reduced illicit cannabis use and improved comorbidity symptoms, even when complete abstinence was not achieved.

Associations of mode of administration on cannabis consumption and subjective intoxication in daily life

OBJECTIVE

As cannabis products are becoming increasingly available and young adults are increasingly using vaporizers to consume cannabis, there is a need to understand how this population is using different modes of administration and the extent to which specific modes are associated with differential cannabis use outcomes. Toward this end, the current study characterized predictors of cannabis mode of administration and examined how consumption levels and subjective intoxication vary as a function of mode of administration in daily life.

METHOD

Participants were 106 young adult cannabis and heavy alcohol users (51% female) who completed up to 14 daily diaries (n = 1,405 person days). Each day, participants reported whether they used any cannabis and, if any, which mode(s) were used, number of hits used per mode, overall subjective intoxication, and the socio-environmental context in which they used cannabis.

RESULTS

Across all cannabis use days, Bong-Only and Vape-Only days were the most common, followed by Multimode, Joint-, Pipe-, and Blunt-Only days. Participants reporting a greater proportion of cannabis use days were more likely to report Bong-Only and Multimode days than Vape-Only days. Compared to Vape-Only days, participants reported fewer hits on Bong-Only days and more hits on Blunt-Only, Pipe-Only, and Multimode days. Participants felt more intoxicated on Bong-Only days than Vape-Only days.

CONCLUSIONS

Mode-specific associations with cannabis consumption and subjective intoxication levels suggest assessing modes of administration may be a meaningful way to guide individual and public health intervention efforts. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Measuring recent cannabis use across modes of delivery: Development and validation of the Cannabis Engagement Assessment

•

The CEA is consistent with expert-recommended guidelines for quantifying cannabis use.

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The CEA is representative of current patterns of recreational cannabis engagement.

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Estimates of cannabis use show strong associations with the timeline followback method.

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The CEA shows good test–retest reliability over a one-week period.

Introduction

Methods of cannabis engagement have proliferated in recent years, which many self-report measures do not adequately capture. There is a clear need for self-report measures that capture current patterns of cannabis use across a range of methods, and that can be used to track changes over time. The current study developed the Cannabis Engagement Assessment (CEA), a self-report measure of past month cannabis use across dry flower, concentrate, and edible products.

Methods

A sample of 349 participants from the undergraduate student population and broader community were recruited. To examine convergent validity of the CEA, participants completed measures of cannabis engagement, cannabis misuse, and use-related problems. To assess divergent validity, participants also completed measures of depression and alcohol use problems. Criterion and test–retest reliability were examined in a subset of 65 participants who re-completed the CEA and a timeline follow-back interview (TLFB).

Results

Indicators of cannabis use frequency and quantity showed good convergence with measures of cannabis use patterns, problematic engagement, and cannabis use-related problems. Divergent validity of the CEA was supported by lower associations with alcohol use problems and depression symptoms. The CEA also showed good test–retest reliability and convergence with estimates of frequency and quantity of cannabis use from the TLFB.

Conclusions

The CEA is a viable self-report measure of cannabis use that is representative of current patterns of recreational cannabis engagement. Its focus on cannabis use in the preceding 30 days also lends itself to measuring changes in use over time.

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.

Efficiency of Inhaled Cannabidiol in Cannabis Use Disorder: The Pilot Study Cannavap

INTRODUCTION

Cannabidiol (CBD), the second most prevalent cannabinoid found in cannabis, is considered to be safe for use. Studies suggest that CBD may be of benefit in treating cannabis use disorder (CUD). In clinical practice, CBD is already being used by patients who are trying to reduce or stop their cannabis consumption. The aim of this study was to assess the potential of CBD inhaled using a vaping device in CUD.

METHODS

This was an exploratory, observational, non-randomized, open-label study conducted at an Addiction Support and Prevention Center in Paris. The primary endpoint was a reduction of at least 50% in the reported number of joints consumed daily at 12 weeks. The participants were given an electronic cigarette along with liquid containing CBD. Nicotine at 6 mg/ml could be added in case of co-consumption of tobacco. They were assessed once a week and the CBD liquid dose was adjusted based on withdrawal signs and cravings (33.3, 66.6 or 100 mg/mL).

RESULTS

Between November 2020 and May 2021, 20 patients were included and 9 (45%) completed the follow-up. All of the participants used tobacco, and were provided a liquid with nicotine. At 12 weeks, 6 patients (30%) had reduced their daily cannabis consumption by at least 50%. The mean number of joints per day was 3, compared to 6.7 at baseline. The mean amount of CBD inhaled per day was 215.8 mg. No symptomatic treatment for cannabis withdrawal was prescribed. Mild adverse effects attributable to CBD and not requiring the prescription of any medicines were reported in a few patients.

CONCLUSION

This research provides evidence in favor of the use of CBD in CUD. It also highlights the benefits of inhalation as the route of CBD administration in patients who use cannabis: inhalation can allow users to self-titrate CBD based on their withdrawal symptoms and cravings. This study illustrates the interest of proposing an addictological intervention targeting at the same time tobacco and cannabis dependence in users who are co-consumers. A double-blind, randomized, placebo-controlled clinical trial is needed to assess the efficacy of inhaled CBD in CUD.Study registration number (IDRCB) issued by the ANSM (Agence nationale de sécurité du médicament et des produits de santé-French National Agency for Medicines and Health Products Safety): 2018-A03256-49. This study received IEC approval from the CPP Sud-Ouest et Outre-Mer 1 (South-West and Overseas 1 IEC) on 15/06/2020 (CPP 1-19-041/ID 3012).

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.

Brain imaging of cannabinoid type I (CB1 ) receptors in women with cannabis use disorder and male and female healthy controls

Cannabis effects are predominantly mediated by pharmacological actions on cannabinoid type 1 (CB1 ) receptors. Prior positron emission tomography (PET) studies in individuals who use cannabis included almost exclusively males. PET studies in females are needed because there are sex differences in cannabis effects, progression to cannabis use disorder (CUD), and withdrawal symptom severity. Females with CUD (N = 10) completed two double-blind cannabis smoking sessions (Session 1: placebo; Session 2: active), and acute cannabis effects were assessed. After Session 2, participants underwent 3 days of monitored cannabis abstinence; mood, craving, and withdrawal symptoms were assessed and a PET scan (radiotracer: [11 C]OMAR) followed. [11 C]OMAR Distribution volume (VT ) from these participants was compared with VT of age/BMI-similar female non-users of cannabis ("healthy controls"; N = 10). VT was also compared between female and male healthy controls (N = 7). Females with CUD displayed significantly lower VT than female healthy controls in specific brain regions (hippocampus, amygdala, cingulate, and insula). Amygdala VT was negatively correlated with mood changes (anger/hostility) during abstinence, but VT was not correlated with other withdrawal symptoms or cannabis effects. Among healthy controls, females had significantly higher VT than males in all brain regions examined. Chronic cannabis use appears to foster downregulation of CB1 receptors in women, as observed previously in men, and there are inherent sex differences in CB1 availability. Future studies should elucidate the time course of CB1 downregulation among females who use cannabis and examine the relation between CB1 availability and cannabis effects among other populations (e.g., infrequent users; medicinal users).

Non-abstinent treatment outcomes for cannabis use disorder

BACKGROUND

Abstinence remains a standard outcome for potential treatment interventions for Cannabis Use Disorder (CUD). However, there needs to be validation of non-abstinent outcomes. This study explores reductions in self-reported days of use as another viable outcome measure using data from three completed randomized placebo-controlled clinical trials of pharmacological interventions for CUD.

METHODS

The three trials tested the effect of quetiapine (QTP, n = 113); dronabinol (DRO, n = 156); and lofexidine + dronabinol (LFD, n = 122). Self-reported cannabis use was categorized into three use-groups/week: heavy (5-7 days/week), moderate (2-4 days/week) and light use (0-1 days/week). Multinomial logistic regressions analyzed the treatment by time effect on the likelihood of light and moderate use compared to heavy use in each study.

RESULTS

Across the three trials, there was no significant overall time-by-treatment interaction (QTP: p = .06; DRO: p = .15; LFD: p = .21). However, the odds of moderate compared to heavy use were significantly higher in treatment than in placebo groups starting around the midpoint of each trial. No treatment differences were found between the odds of light compared to heavy use.

CONCLUSIONS

While study-end abstinence rates have been a standard treatment outcome for CUD trials, reduction from heavy to moderate use has not been standardly assessed. During the last several weeks of each trial, those on active medication were more likely to move from heavy to moderate use, which suggests that certain medications may be more impactful than previously assessed. Future studies should determine if this pattern is associated with less CUD severity and/or improved quality of life.

Impact of cannabis use on outcomes of patients admitted to an involuntary psychiatric unit: A retrospective cohort study

INTRODUCTION

Cannabis is associated with an increased risk of mental disorders, including the onset or adverse evolution of schizophrenia, bipolar disorder and depression. The aim of our study was to examine how cannabis use influences length of stay and readmissions in a unit of involuntary care.

METHOD

All patients admitted to one secure adult psychiatry unit in France in 2016 were included (n = 370). Patients were assigned to one of two groups according to detection of urinary tetrahydrocannabinol (THC + or -). Clinical outcomes, such as length of stay and readmissions, were compared between the groups in multivariate analyses.

RESULTS

We identified 130 THC + patients and 240 THC- patients. THC + patients were often young men. In adjusted analyses, THC + status was significantly associated with one-year readmissions (OR = 2.29, p = .0082) and more prescriptions of benzodiazepines (OR = 1.93, p = .02), but not antipsychotics, at discharge.

CONCLUSIONS

Cannabis users seem to have a particular profile in secure units, and are associated with specific diagnoses and treatments, and a higher risk of readmissions. Adapted management strategies might be warranted for these patients.

Self-reported symptoms of cannabis use disorder: Psychometric testing and validation

Cannabis use disorder (CUD) is commonly assessed using self-report items based on its symptoms as defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM) that are scored on a dichotomous scale (yes/no) to indicate symptom presence; however, scoring items on a dichotomy may result in relatively limited sensitivity for research. Thus, we developed a 13-item measure of CUD, the Self-Reported Symptoms of CUD (SRSCUD), based on the 11 symptoms described in the DSM-5 that is scored on a 4-point response scale indicating degree of severity. In the present study, we conduct an initial evaluation of the psychometric properties of the SRSCUD. Past-month cannabis users (N = 2,077) were recruited from nine universities in nine states throughout the U.S. Each item of the SRSCUD loaded saliently onto a single factor of CUD symptoms in both exploratory and confirmatory factor analyses. The SRSCUD was strongly correlated with measures of cannabis use, dependence severity, and cannabis-related problems. In addition, the SRSCUD was moderately positively correlated with a well-known risk factor for CUD (coping motives) and moderately negatively correlated with a well-known protective factor for CUD (protective behavioral strategies). These correlations mostly remained statistically significant while controlling for CUD symptom count and diagnosis using dichotomized SRSCUD items. Receiver operator characteristic curve analyses revealed that the SRSCUD had excellent sensitivity/specificity for predicting probable CUD. Although more research evaluating performance of the SRSCUD compared to a clinical diagnosis is needed, we found preliminary evidence for construct validity of this measure. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Motivational Interviewing Skills as Predictors of Change in Emerging Adult Risk Behavior

Emerging adulthood is a unique developmental stage during which significant transitions in living environment, social networks, personal responsibilities, and identity development occur. Stress associated with these transitions relates to increases in health-risk behaviors, such as substance use and high-risk sexual behavior. This research examined health-risk behavior outcomes associated with the Young Adult Family Check-Up (YA-FCU). The YA-FCU comprises three sessions: an initial interview, an ecological assessment, and a feedback session that integrates motivational interviewing (MI) techniques. This study measured treatment fidelity of the YA-FCU and the extent to which therapists adhered to principles of MI during feedback sessions. Therapists included both licensed psychologists and trainees. The study also examined the relationship between therapists' MI fidelity and client change talk (CT), in order to determine if MI fidelity and client CT predicted postintervention health-risk behaviors among emerging adults who participated in the YA-FCU. Measures of health-risk behaviors were collected pre- and post- intervention. Results indicated overall adequate treatment fidelity. MI fidelity was positively related to client CT. Several indicators of MI fidelity predicted decreases in emerging adults' health-risk behaviors. For example, therapist ratio of reflections to questions predicted a decline in emerging adults' alcohol use frequency and marijuana use quantity. These results have important implications for YA-FCU training and implementation and indicate that MI consistent skills might be a mechanism of change in the YA-FCU intervention.

Cannabis use and cannabis use disorder

Cannabis use disorder (CUD) is an underappreciated risk of using cannabis that affects ~10% of the 193 million cannabis users worldwide. The individual and public health burdens are less than those of other forms of drug use, but CUD accounts for a substantial proportion of persons seeking treatment for drug use disorders owing to the high global prevalence of cannabis use. Cognitive behavioural therapy, motivational enhancement therapy and contingency management can substantially reduce cannabis use and cannabis-related problems, but enduring abstinence is not a common outcome. No pharmacotherapies have been approved for cannabis use or CUD, although a number of drug classes (such as cannabinoid agonists) have shown promise and require more rigorous evaluation. Treatment of cannabis use and CUD is often complicated by comorbid mental health and other substance use disorders. The legalization of non-medical cannabis use in some high-income countries may increase the prevalence of CUD by making more potent cannabis products more readily available at a lower price. States that legalize medical and non-medical cannabis use should inform users about the risks of CUD and provide information on how to obtain assistance if they develop cannabis-related mental and/or physical health problems.

The Lower-Risk Cannabis Use Guidelines (LRCUG): A ready-made targeted prevention tool for cannabis in New Zealand

Cannabis use is common, especially among young people, and associated with risks for select acute and chronic adverse health and social outcomes. New Zealand features overall high cannabis use levels, yet may soon follow other jurisdictions and implement legalization of non-medical cannabis use and supply towards public health objectives. While existing cannabis-oriented interventions mainly focus on primary prevention and treatment (e.g., for dependence), key harms from use are crucially influenced by risk factors that can be modified by the user. On this basis, and similar to other health behavior-oriented interventions, ‘Lower-Risk Cannabis Use Guidelines’ (LRCUG), consisting of 10 recommendation clusters for lower-risk use, were systematically developed in Canada as an evidence-based, targeted prevention tool towards reducing adverse outcomes among cannabis users. We briefly summarize the concept of and experiences with implementation of the LRCUG elsewhere, and describe how their adoption as a population health intervention may serve public health goals of possible cannabis legalization in New Zealand and elsewhere.

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Cannabis is common, but involves risks for acute and chronic adverse outcomes.

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Many adverse outcomes are influenced by user-modifiable risk factors.

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Cannabis use and supply legalization may be implemented in New Zealand.

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Evidence-based ‘Lower-Risk Cannabis Use Guidelines’ are a targeted prevention tool.

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LRCUG may serve a valuable intervention towards legalization’s public health outcomes.

A systematic review and Bayesian meta-analysis of interventions which target or assess co-use of tobacco and cannabis in single- or multi-substance interventions

BACKGROUND AND AIMS

Tobacco and cannabis are commonly co-used, and evidence for the influence of co-use on quit outcomes for either substance is mixed. We sought to determine the efficacy of tobacco and/or cannabis use interventions delivered to co-users on cannabis and tobacco use outcomes.

METHOD

Systematic review with meta-analysis and narrative review, using five databases and author requests for co-use data. Controlled and uncontrolled intervention studies focusing on treatment of tobacco and/or cannabis use assessing use of both pre- and post-intervention were included. Prevention interventions were excluded. Bayesian meta-analysis was used across four outcome measures: risk ratio for tobacco and cannabis cessation post-intervention separately; standardized mean change for tobacco and cannabis reduction post-intervention separately. Narrative reporting of the same outcome measures in non-randomized clinical trials (non-RCTs) and quality assessment of all included studies were conducted.

RESULTS

Twenty studies (12 RCTs and eight uncontrolled) were included. Bayesian meta-analysis with informative priors based on existing data of 11 RCTs (six single-substance, five multi-substance interventions) delivered to co-users (n = up to 1117) showed weak evidence for an effect on cannabis cessation [risk ratio (RR) = 1.48, credibility interval (CrI) = 0.92, 2.49, eight studies] and no clear effect on tobacco cessation (RR = 1.10, CrI = 0.68, 1.87, nine studies). Subgroup analysis suggested that multi-substance interventions might be more effective than cannabis-targeted interventions on cannabis cessation (RR = 2.19, CrI = 1.10, 4.36 versus RR = 1.39, CrI = 0.75, 2.74). A significant intervention effect was observed on cannabis reduction (RR = 0.25, CrI = 0.03, 0.45, nine studies) but not on tobacco reduction (RR = 0.06, CrI = -0.11, 0.23, nine studies). Quality of evidence was moderate, although measurement of co-use and cannabis use requires standardization. Uncontrolled studies targeting both cannabis and tobacco use indicated feasibility and acceptability.

CONCLUSIONS

Single and multi-substance interventions addressing tobacco and/or cannabis have not shown a clear effect on either tobacco or cannabis cessation and reduction among co-users. However, dual substance interventions targeting tobacco and cannabis appear feasible.

The state of clinical outcome assessments for cannabis use disorder clinical trials: A review and research agenda

There is considerable variability in the use of outcome measures in clinical trials for cannabis use disorder (CUD), and a lack of consensus regarding optimal outcomes may have hindered development and approval of new pharmacotherapies. The goal of this paper is to summarize an evaluation of assessment measures and clinical endpoints for CUD clinical trials, and propose a research agenda and priorities to improve CUD clinical outcome assessments. The primary recommendation is that sustained abstinence from cannabis should not be considered the primary outcome for all CUD clinical trials as it has multiple limitations. However, there are multiple challenges to the development of a reliable and valid indicator of cannabis reduction, including the lack of a standard unit of measure for the various forms of cannabis and products and the limitations of currently available biological and self-report assessments. Development of a core toolkit of assessments is needed to both allow flexibility for study design, while facilitating interpretation of outcomes across trials. Four primary agenda items for future research are identified to expedite development of improved clinical outcome assessments for this toolkit: (1) determine whether minimally invasive biologic assays could identify an acute level of cannabis use associated with psychomotor impairment or other cannabis-related harms; (2) create an indicator of quantity of cannabis use that is consistent across product types; (3) examine the presence of cannabis-specific functional outcomes; and (4) identify an optimal duration to assess changes in CUD diagnostic criteria.

Measuring Within-Individual Cannabis Reduction in Clinical Trials: A Review of the Methodological Challenges

Purpose

Cannabis abstinence traditionally is the primary outcome in cannabis use disorder (CUD) treatment trials. Due to the changing legality of cannabis, patient goals, and preliminary evidence that suggests individuals who reduce their cannabis use may show functional improvements, cannabis reduction is a desirable alternative outcome in CUD trials. We review challenges in measuring cannabis reduction and the evidence to support various definitions of reduction.

Findings

Reduction in number of cannabis use days was associated with improvements in functioning across several studies. Reductions in quantity of cannabis used was inconsistently associated with improvements in functioning, though definitions of quantity varied across studies. Different biomarkers may be used depending on the reduction outcome.

Conclusions

Biologically-confirmed reductions in frequency of cannabis use days may represent a viable endpoint in clinical trials for cannabis use disorder. Additional research is needed to better quantify reduction in cannabis amounts.