Development and validation of the cannabis experiences questionnaire - Intoxication effects checklist (CEQ-I) short form

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.

Predictive impact of different acute cannabis intoxication effects with regard to abstinence motivation and cessation of use

Cannabis use is a common risk factor for psychoses. But although prevalence of consumption as well as potency of cannabis increased, the incidence of schizophrenia remained stable. The discontinuation hypothesis suggests that a potential increase of psychoses incidence may be relativized by more frequent cessation of consumption due to higher rates of adverse psychosis-like intoxication effects (PLE), caused by stronger cannabis. A mixed methods online survey was administered to 441 current and past users to analyze the predictive impact of different acute intoxication effects regarding abstinence motivation/cessation of use. Our hypothesis was that PLE would be experienced as the most aversive intoxication effect and therefore have the highest predictive significance. Possible confounds were included (craving, patterns of consumption and sociodemographics). Further analyzes compared past versus current users regarding the quality of intoxication effects, suggesting that past users retrospectively experienced more unpleasant experiences than current users. Free-text data explored subjective reasons for abstinence. We found that paranoid/dysphoric intoxication effects were most predictive for abstinence motivation. Less predictive were psychosis-like intoxication effects such as hallucinations. Group comparisons revealed significant more unpleasurable and less positive intoxication effects in past users compared with current users. Current users with the intention to stop consumption showed significantly more paranoia/dysphoria intoxication compared to users with no intention to stop use. As a conclusion, different intoxication experiences have different effects on abstinence motivation and substance use behavior. They therefore provide a focus that should be increasingly integrated into treatment concepts.

Development and initial validation of a reliable German self-report measure to assess acute cannabis intoxication-effects (CanTox-17)

OBJECTIVES

Both positive and negative including psychotic-like cannabis intoxication effects are well-established. Yet, consequences for consumption patterns, addictive behavior or psychotic developments are poorly researched in general, in Germany not at all. Thus, objective was to develop the first German-language questionnaire operationalizing acute cannabis intoxication effects, based on the original "Cannabis Experience Questionnaire" (CEQ).

METHODS

After expert translation of the CEQ, items related to acute intoxication effects were presented to a sample of 537 cannabis users. Four- and five-factorial solutions of explorative factor analysis with a randomly split sub-sample 1 were cross-validated by confirmatory factor analysis on sub-sample 2.

RESULTS

After content review of factors and analysis of external validity, a 17 item four-factorial model was approved. Factors are (1) "paranoia/dysphoria", (2) "confusion/disorientation", (3) "euphoria/creativity", (4) "psychosis-like/loss of reality". Model fit is satisfactory (RMSEA = 0.058, SRMR = 0.065, CFI = 0.929, TLI = 0.914). Correlations with corresponding external measures support construct validity.

CONCLUSIONS

The present questionnaire is a time-efficient, valid and reliable instrument. Thus, predictors of different cannabis intoxication effects can be analysed for the first time in German-speaking area, as well as their significance for substance use or psychosis risk.

Insights about Cannabis and Psychosis Using Video Games for Young People with a First Episode of Psychosis, particularly those from Black Racialized Backgrounds: Study Design

Background

Cannabis use disorder among young people with a first episode of psychosis contributes to relapse, hospitalization, and impaired functioning. However, few studies have examined what young people with early phase psychosis, particularly those from Black racialized communities, understand or appreciate about this relationship, even though they may be at risk. There are no formally tested knowledge translation strategies that disseminate these research findings for young people with emerging psychosis from Black racialized communities.

Objective

This study aims to conceptualize what young people with early phase psychosis/cannabis use disorder understand about the relationship between cannabis and psychosis, focusing on people from racialized backgrounds. This study also aims to assess whether the knowledge translation product, the “Back to Reality Series,” increases awareness of the impact of cannabis use on psychosis from the perspectives of young people with emerging psychosis and cannabis use disorder from Black African and Caribbean communities.

Methods

Qualitative analysis will reveal themes from qualitative interviews about cannabis and psychosis from the perspectives of young people with emerging psychosis and cannabis use disorder from Black African and Caribbean communities. Perceptions before and after exposure to the Back to Reality Series will be qualitatively analyzed. A control game will be used for comparison, and scores on a quiz after playing the Back to Reality Series will be quantitatively analyzed to establish whether the Back to Reality Series raises awareness of the effects of cannabis on psychosis. An advisory council involving young people from Black communities, family members, and clinicians will bring community perspectives to this research.

Results

We began recruiting participants for this study in September 2021. We will complete data collection on demographic and clinical factors, qualitative interviews, and quantitative assessments of the Back to Reality Series.

Conclusions

The voices of young people from racialized backgrounds will generate preliminary data to inform early psychosis programs, addressing cannabis use in this population. The findings may advance the use of a new knowledge translation product that deals with gaps in knowledge about cannabis use for people experiencing early phase psychosis, particularly those from racialized communities.

International Registered Report Identifier (IRRID)

DERR1-10.2196/36758

Cannabis-induced dysphoria/paranoia mediates the link between childhood trauma and psychotic-like experiences in young cannabis users

Childhood trauma (abuse and neglect) is a major risk factor for cannabis use disorder and psychotic-spectrum disorders. Psychotic-like experiences (PLEs) in young people who use cannabis may be an early indicator of psychosis risk following cannabis use. We examined whether (i) childhood trauma moderates the association between cannabis use and PLEs, (ii) the association between childhood trauma and cannabis use is mediated by subjective effects of cannabis (euphoria and dysphoria/paranoia), and (iii) the association between childhood trauma and PLEs is also mediated by these subjective effects. Participants were 2630 cannabis users (aged 16-25) recruited online. They were asked to complete a cross-sectional survey measuring cannabis and other substance use, childhood trauma, PLEs, and the subjective effects of cannabis (euphoria and dysphoria/paranoia). A significant interaction indicated that the effect of cannabis on PLE frequency was stronger for individuals with more severe childhood trauma. Childhood trauma was also associated with greater cannabis use and PLE frequency, both of which were mediated by subjective dysphoria/paranoia when using the drug. This suggests childhood trauma is associated with greater PLEs in young people who use cannabis, which may be linked with an increased susceptibility to the dysphoric/paranoid subjective effects when using the drug. Childhood trauma should be addressed early in young people who use cannabis to mitigate the psychosis-associated harms of the drug.

Association of extent of cannabis use and psychotic like intoxication experiences in a multi-national sample of first episode psychosis patients and controls

BACKGROUND

First episode psychosis (FEP) patients who use cannabis experience more frequent psychotic and euphoric intoxication experiences compared to controls. It is not clear whether this is consequent to patients being more vulnerable to the effects of cannabis use or to their heavier pattern of use. We aimed to determine whether extent of use predicted psychotic-like and euphoric intoxication experiences in patients and controls and whether this differs between groups.

METHODS

We analysed data on patients who had ever used cannabis (n = 655) and controls who had ever used cannabis (n = 654) across 15 sites from six countries in the EU-GEI study (2010-2015). We used multiple regression to model predictors of cannabis-induced experiences and to determine if there was an interaction between caseness and extent of use.

RESULTS

Caseness, frequency of cannabis use and money spent on cannabis predicted psychotic-like and euphoric experiences (p ⩽ 0.001). For psychotic-like experiences (PEs) there was a significant interaction for caseness × frequency of use (p < 0.001) and caseness × money spent on cannabis (p = 0.001) such that FEP patients had increased experiences at increased levels of use compared to controls. There was no significant interaction for euphoric experiences (p > 0.5).

CONCLUSIONS

FEP patients are particularly sensitive to increased psychotic-like, but not euphoric experiences, at higher levels of cannabis use compared to controls. This suggests a specific psychotomimetic response in FEP patients related to heavy cannabis use. Clinicians should enquire regarding cannabis related PEs and advise that lower levels of cannabis use are associated with less frequent PEs.

Are researchers getting the terms used to denote different types of recreational cannabis right?-a user perspective

BACKGROUND

While current cannabis research has advanced our understanding into the effects of its individual components, there is a pressing need to identify simple terminology that is understood in the same way by researchers and users of cannabis. Current categorisation in research focuses on the two main cannabinoids: delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD); and two different species of cannabis: indica and sativa. Recreational cannabis has also been categorised by researchers as 'skunk' or 'hash'. Focusing on individuals who use cannabis frequently, this study aimed to identify views on current terms used to denote different types of cannabis and to identify terms validated by participants. These views were extracted from responses of the Cannabis Experiences Questionnaire (CEQ), a widely used instrument in the literature.

METHODS

We qualitatively analysed 236 free-text responses from Question 23 of the CEQ survey (using Iterative Categorisation) relating to categorization and consumption methods. Data was used from a previous study (Sami et al., Psychol Med 49:103-12, 2019), which recruited a convenience sample of 1231 participants aged 18 years and above who had previously used cannabis.

RESULTS

Regarding type of cannabis used, specific strain names (n = 130), concentrates (n = 37), indica/sativa (n = 22) and THC/CBD terms (n = 22) were mentioned. Other terms used were hybrids (n = 10), origins of specific strains (n = 17), edibles (n = 8), and herbal cannabis (n = 7). Regarding problems with specific terms, participants were skeptical about terms such as skunk and super skunk (n = 78) preferring terms like THC/CBD, indica/sativa, specific marketed strains and references to preparation methods.

CONCLUSIONS

The results suggest a disparity between the common terms used by researchers in academia and those used by cannabis consumers. While there are advantages and limitations of using these terms to bridge views of researchers and individuals who use cannabis, this study underscores the importance of formally assessing chemical constituents rather than relying on self-report data and of incorporating cannabis user views on current terms used in research, potentially also incorporating descriptors of preparation and consumption methods.

A within-person comparison of the subjective effects of higher vs. lower-potency cannabis

BACKGROUND

Cannabis concentrates have much higher concentrations of THC than marijuana (flower) and are quickly gaining popularity in the United States. One hypothesis is that use of higher-THC cannabis (concentrates) might result in greater intoxication and more severe acute negative effects than lower-THC cannabis (marijuana), but few studies have compared the subjective effects of concentrates and marijuana.

METHODS

Current (past-year) cannabis users were recruited online to complete a survey about their cannabis use. Cannabis users who reported using both marijuana and concentrates (n = 574) answered questions about the subjective effects of marijuana and, subsequently, the subjective effects of concentrates. Subjective effects were obtained for the following domains: affect, cognitive function, psychotic-like experiences, physiological effects, and reduced consciousness.

RESULTS

Participants reported using marijuana between 5-6 times per week and concentrates slightly more than once per month. Within-person comparisons of the subjective effects of marijuana and concentrates showed that marijuana was rated as producing greater overall positive effects (Marijuana: M = 5.6, Concentrates: M = 4.5; Cohen's d = 0.75, paired t(561) = 14.67, p < .001), including greater positive affect and enhanced cognitive function. Negative effects of both marijuana and concentrates were minimal. Marijuana was selected over concentrates as the 'preferred type' of cannabis by 77.5 % of participants.

CONCLUSIONS

The main difference in the subjective effects of marijuana and concentrates is in terms of their positive effects, with marijuana producing greater positive effects than concentrates. Negative effects of marijuana and concentrates were small, suggesting that extreme negative effects are unlikely for regular cannabis users.

A Web-Based Program for Cannabis Use and Psychotic Experiences in Young People (Keep It Real): Protocol for a Randomized Controlled Trial

BACKGROUND

Young Australians (16-25 years) have the highest rates of past-month cannabis use in the world. Cannabis use increases the risk of alcohol and other drug disorders and depressive disorders, and has a robust dose-response association with psychotic experiences (PEs) and disorders. PEs are subthreshold positive psychotic symptoms, including delusions and hallucinations, which increase the risk of substance use, depressive or anxiety disorders, and psychotic disorders. Access to effective web-based early interventions targeting both cannabis use and PEs could reduce such risk in young people.

OBJECTIVE

The objective of this study is to determine the efficacy and cost-effectiveness of the Keep it Real web-based program compared to an information-only control website among young cannabis users (16-25 years) with PEs.

METHODS

Participants are recruited online, and consenting individuals meeting inclusion criteria (aged 16-25 years, who have used cannabis in the past month and experienced PEs in the past 3 months) are automatically randomized to either the Keep it Real web-based program (n=249) or an information-only control website (n=249). Both websites are self-guided (fully automated). The baseline and follow-up assessments at 3, 6, 9, and 12 months are self-completed online. Primary outcome measures are weekly cannabis use, PEs, and the relative cost-effectiveness for quality-adjusted life years. Secondary outcomes include other substance use and related problems, PE-related distress, cannabis intoxication experiences, severity of cannabis dependence, depression/anxiety symptoms, suicidality, and mental well-being and functioning.

RESULTS

Recruitment commenced in February 2019, and the results are expected to be submitted for publication in mid-2021.

CONCLUSIONS

This study protocol describes a large randomized controlled trial of a new web-based program for young cannabis users experiencing PEs. If effective, the accessibility and scalability of Keep it Real could help reduce growing public health concerns about the significant social, economic, and health impacts of cannabis use.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12618001107213; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=374800.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/15803.

An evolutionary perspective on paranoia

Paranoia is the most common symptom of psychosis but paranoid concerns occur throughout the general population. Here, we argue for an evolutionary approach to paranoia across the spectrum of severity that accounts for its complex social phenomenology - including the perception of conspiracy and selective identification of perceived persecutors - and considers how it can be understood in light of our evolved social cognition. We argue that the presence of coalitions and coordination between groups in competitive situations could favour psychological mechanisms that detect, anticipate and avoid social threats. Our hypothesis makes testable predictions about the environments in which paranoia should be most common as well as the developmental trajectory of paranoia across the lifespan. We suggest that paranoia should not solely be viewed as a pathological symptom of a mental disorder but also as a part of a normally-functioning human psychology.

Psychotic-like experiences with cannabis use predict cannabis cessation and desire to quit: a cannabis discontinuation hypothesis

BACKGROUND

Evidence suggests that cannabis-induced psychotic-like experiences may be a marker of psychosis proneness. The effect of such experiences on cannabis use has not systematically been examined.

METHODS

We undertook a mixed-methods online survey of 1231 cannabis users (including 926 continued users) using the Cannabis Experiences Questionnaire. We examined the effect of psychotic-like and pleasurable experiences on cessation of cannabis and intention to quit. Socio-demographic variables, cannabis use parameters and substance misuse history were included as covariates. Free-text data explored subjective reasons for changes in use.

RESULTS

Cessation of cannabis use was associated with greater psychotic-like experiences [p &lt; 0.001, Exp(B) 1.262, 95% confidence interval (CI) 1.179-1.351], whilst continued cannabis users were more likely to report pleasurable experiences [p &lt; 0.001, Exp(B) 0.717, 95% CI 0.662-0.776]. Intention to quit cannabis in continued users was associated with greater psychotic-like experiences [p &lt; 0.003, Exp(B) 1.131, 95% CI 1.044-1.225], whilst intention to not quit was significantly associated with increased pleasurable experiences [p &lt; 0.015, Exp(B) 0.892, 95% CI 0.814-0.978]. Whereas former users clearly ascribed cessation to negative experiences, continued users who expressed intention to quit less readily ascribed the intention to negative experiences.

CONCLUSIONS

Elucidation of psychotic-like experiences may form the basis of a therapeutic intervention for those who wish to quit. Cessation in those with cannabis-induced psychotomimetic experiences may offset the risk for the development of a psychotic disorder, in this higher risk group.