Adolescent cannabis use, baseline prodromal symptoms and the risk of psychosis

On the proportion of patients who experience a prodrome prior to psychosis onset: A systematic review and meta-analysis

BACKGROUND

Preventing or delaying the onset of psychosis requires identification of those at risk for developing psychosis. For predictive purposes, the prodrome - a constellation of symptoms which may occur before the onset of psychosis - has been increasingly recognized as having utility. However, it is unclear what proportion of patients experience a prodrome or how this varies based on the multiple definitions used.

METHODS

We conducted a systematic review and meta-analysis of studies of patients with psychosis with the objective of determining the proportion of patients who experienced a prodrome prior to psychosis onset. Inclusion criteria included a consistent prodrome definition and reporting the proportion of patients who experienced a prodrome. We excluded studies of only patients with a prodrome or solely substance-induced psychosis, qualitative studies without prevalence data, conference abstracts, and case reports/case series. We searched Ovid MEDLINE, Embase (Ovid), APA PsycInfo (Ovid), Web of Science Core Collection (Clarivate), Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, APA PsycBooks (Ovid), ProQuest Dissertation & Thesis, on March 3, 2021. Studies were assessed for quality using the Critical Appraisal Checklist for Prevalence Studies. Narrative synthesis and proportion meta-analysis were used to estimate prodrome prevalence. I2 and predictive interval were used to assess heterogeneity. Subgroup analyses were used to probe sources of heterogeneity. (PROSPERO ID: CRD42021239797).

RESULTS

Seventy-one articles were included, representing 13,774 patients. Studies varied significantly in terms of methodology and prodrome definition used. The random effects proportion meta-analysis estimate for prodrome prevalence was 78.3% (95% CI = 72.8-83.2); heterogeneity was high (I2 97.98% [95% CI = 97.71-98.22]); and the prediction interval was wide (95% PI = 0.411-0.936). There were no meaningful differences in prevalence between grouped prodrome definitions, and subgroup analyses failed to reveal a consistent source of heterogeneity.

CONCLUSIONS

This is the first meta-analysis on the prevalence of a prodrome prior to the onset of first episode psychosis. The majority of patients (78.3%) were found to have experienced a prodrome prior to psychosis onset. However, findings are highly heterogenous across study and no definitive source of heterogeneity was found despite extensive subgroup analyses. As most studies were retrospective in nature, recall bias likely affects these results. While the large majority of patients with psychosis experience a prodrome in some form, it is unclear if the remainder of patients experience no prodrome, or if ascertainment methods employed in the studies were not sensitive to their experiences. Given widespread investment in indicated prevention of psychosis through prospective identification and intervention during the prodrome, a resolution of this question as well as a consensus definition of the prodrome is much needed in order to effectively direct and organize services, and may be accomplished through novel, densely sampled and phenotyped prospective cohort studies that aim for representative sampling across multiple settings.

Intensity of Psychoactive Substance Use Affects the Occurrence of Prodromal Symptoms of Psychosis

BACKGROUND

Psychosis is defined as a series of symptoms that impair the mind and lead to a kind of loss of reference to reality. Development of psychosis is usually preceded by the appearance of prodromal symptoms. Numerous attempts have been made to find out how psychoactive substances can influence the onset and development of psychotic disorders, but to date there are no studies that show a link between the onset of prodromal symptoms and the use of psychoactive substances.

METHODS

A survey consisting of epidemiological and demographic questions, the Drug Use Disorders Identification Test (DUDIT), and the Prodromal Questionnaire Brief Version (PQ-B) was conducted on social media among users of illegal psychoactive substances, covering 703 study participants.

RESULTS

A total of 39.8% of the respondents had been treated by a psychiatrist, and the most popular drugs used by respondents in their lifetime were tetrahydrocannabinol-containing products, MDMA, amphetamines, and LSD. A significant correlation was found between the DUDIT and the PQ-B values.

CONCLUSIONS

Intensity of psychoactive substance use correlated positively with the risk of appearance and intensity of prodromal symptoms of psychosis. Early exposure to psychoactive substances increased the risk of heavy substance use in adulthood and led to more frequent prodromal states.

Psychosis superspectrum I: Nosology, etiology, and lifespan development

This review describes the Hierarchical Taxonomy of Psychopathology (HiTOP) model of psychosis-related psychopathology, the psychosis superspectrum. The HiTOP psychosis superspectrum was developed to address shortcomings of traditional diagnoses for psychotic disorders and related conditions including low reliability, arbitrary boundaries between psychopathology and normality, high symptom co-occurrence, and heterogeneity within diagnostic categories. The psychosis superspectrum is a transdiagnostic dimensional model comprising two spectra-psychoticism and detachment-which are in turn broken down into fourteen narrow components, and two auxiliary domains-cognition and functional impairment. The structure of the spectra and their components are shown to parallel the genetic structure of psychosis and related traits. Psychoticism and detachment have distinct patterns of association with urbanicity, migrant and ethnic minority status, childhood adversity, and cannabis use. The superspectrum also provides a useful model for describing the emergence and course of psychosis, as components of the superspectrum are relatively stable over time. Changes in psychoticism predict the onset of psychosis-related psychopathology, whereas changes in detachment and cognition define later course. Implications of the superspectrum for genetic, socio-environmental, and longitudinal research are discussed. A companion review focuses on neurobiology, treatment response, and clinical utility of the superspectrum, and future research directions.

Unhealthy behaviors associated with mental health disorders: a systematic comparative review of diet quality, sedentary behavior, and cannabis and tobacco use

Background

There are well-established literatures documenting the associations between mental disorders and unhealthy behaviors such as poor diet quality, sedentary behavior, and cannabis and tobacco use. Few studies have attempted to understand the respective findings in light of each other, however.

Objective

The purpose of this review was to assemble comparable data for each behavior-disorder association and assess the associations in terms of their overall strength. The review aimed to include a representative, but not exhaustive, range of studies that would allow for explorative comparisons.

Methods

Eligible studies were identified via Pubmed searches and citation searching, restricted to publications no older than 2015 written in English. To obtain comparable data, only studies that reported findings as odds ratios were included, and risk of bias related to study samples, behavioral measurement disparities, and control variables was assessed via sensitivity analyses. Findings for each disorder were compared on the basis of different measures of central tendency.

Results

From 3,682 records, 294 studies were included. The review found evidence of associations between each of the four unhealthy behaviors and psychosis, depression, anxiety, bipolar disorder, attention-deficit/hyperactivity disorder (ADHD), and post-traumatic stress disorder (PTSD), while personality disorder was only investigated in relation to cannabis and tobacco use. In overall comparison, the associations were generally of similar strength, and only the association between cannabis use and personality disorder was exceptional in terms of being significantly stronger than its counterparts across disorders and across behaviors. Analyses of bias risk identified some influence from behavioral measurement disparities and lack of adequate statistical control, but findings were generally robust across a range of sensitivity analyses.

Conclusion

This explorative and comparative review found that poor diet quality, sedentary behavior, and cannabis and tobacco use are about equally strongly associated with a range of different mental disorders. Given the general nature of these associations, we should probably understand them to reflect a general and shared etiology. However, the findings in this review should be regarded as tentative until confirmed by more comprehensive investigations.

Investigating the associations of age of initiation and other psychosocial factors of singular alcohol, tobacco and marijuana usage on polysubstance use: analysis of a population-based survey in Jamaica

OBJECTIVES

This study aimed to examine concurrent polysubstance use of alcohol, tobacco and marijuana and determine correlations with access to marijuana, friend and familial drug use habits, risk perception and the age of initiation associated with the singular use of these substances.

DESIGN

A secondary data analysis.

SETTING

Used the Jamaica National Drug Prevalence Survey 2016 dataset.

PARTICIPANTS

Involved the entire dataset comprising 4623 randomly selected respondents between 12 and 65 years old.

OUTCOME MEASURES

Primary outcome: concurrent polysubstance use recorded as using two or more of alcohol, tobacco and marijuana. Predictor variables include risk perception and age of initiation of singular alcohol, tobacco and marijuana use, ease of marijuana access and family and friend alcohol and illegal drug use.

RESULTS

Approximately 58%-66% of respondents commenced singular alcohol, tobacco or marijuana use under 17. Participants commencing marijuana use at 11 years and under and between 12 and 17 were 3.346 and 4.560 times more likely to report past month concurrent polysubstance use (p=0.030 and p<0.001). Respondents who did not believe that smoking tobacco sometimes (p=0.049), and smoking marijuana sometimes and often was harmful, had increased odds of concurrent polysubstance use (p=0.047 and p<0.001, respectively). Respondents who indicated access to marijuana as easy were significantly more likely to report past month concurrent polysubstance use compared with those who reported access as difficult (p=0.002). Participants who indicated that friends or family members get drunk and take illegal drugs were associated with 1.722 and 1.864 increased odds of reporting past month concurrent polysubstance use (p=0.004 and p=0.017, respectively).

CONCLUSIONS

Decreased perceived risk, childhood and adolescent age of initiation and easy access to marijuana were significantly associated with polysubstance use among Jamaicans. The influence of friends and family members' drug and alcohol use behaviours on individuals developing polysubstance use habits further endorses the need for interventions.

The association between reasons for first using cannabis, later pattern of use, and risk of first-episode psychosis: the EU-GEI case-control study

BACKGROUND

While cannabis use is a well-established risk factor for psychosis, little is known about any association between reasons for first using cannabis (RFUC) and later patterns of use and risk of psychosis.

METHODS

We used data from 11 sites of the multicentre European Gene-Environment Interaction (EU-GEI) case-control study. 558 first-episode psychosis patients (FEPp) and 567 population controls who had used cannabis and reported their RFUC.We ran logistic regressions to examine whether RFUC were associated with first-episode psychosis (FEP) case-control status. Path analysis then examined the relationship between RFUC, subsequent patterns of cannabis use, and case-control status.

RESULTS

Controls (86.1%) and FEPp (75.63%) were most likely to report 'because of friends' as their most common RFUC. However, 20.1% of FEPp compared to 5.8% of controls reported: 'to feel better' as their RFUC (χ2 = 50.97; p < 0.001). RFUC 'to feel better' was associated with being a FEPp (OR 1.74; 95% CI 1.03-2.95) while RFUC 'with friends' was associated with being a control (OR 0.56; 95% CI 0.37-0.83). The path model indicated an association between RFUC 'to feel better' with heavy cannabis use and with FEPp-control status.

CONCLUSIONS

Both FEPp and controls usually started using cannabis with their friends, but more patients than controls had begun to use 'to feel better'. People who reported their reason for first using cannabis to 'feel better' were more likely to progress to heavy use and develop a psychotic disorder than those reporting 'because of friends'.

Consequences of adolescent drug use

Substance use in adolescence is a known risk factor for the development of neuropsychiatric and substance use disorders in adulthood. This is in part due to the fact that critical aspects of brain development occur during adolescence, which can be altered by drug use. Despite concerted efforts to educate youth about the potential negative consequences of substance use, initiation remains common amongst adolescents world-wide. Additionally, though there has been substantial research on the topic, many questions remain about the predictors and the consequences of adolescent drug use. In the following review, we will highlight some of the most recent literature on the neurobiological and behavioral effects of adolescent drug use in rodents, non-human primates, and humans, with a specific focus on alcohol, cannabis, nicotine, and the interactions between these substances. Overall, consumption of these substances during adolescence can produce long-lasting changes across a variety of structures and networks which can have enduring effects on behavior, emotion, and cognition.

Concern for Police Brutality, Societal Discrimination, and School Shootings and Subsequent Cigarette and Cannabis Use in Los Angeles County Hispanic and Non-Hispanic White Youth: a Longitudinal Study

OBJECTIVE

Examine if concerns for police brutality, societal discrimination, and school shootings relate to subsequent cigarette and cannabis use among Hispanic and non-Hispanic White (NHW) youth. Hispanic youth may be particularly vulnerable to such concern.

METHODS

Data are from the University of Southern California's Happiness and Health Survey, a prospective cohort study, which followed Hispanic (N = 1007) and NHW (N = 251) students from ten inner-city and suburban high schools in Los Angeles County, starting from 2013 until 2019. Participants reported concern, worry, and stress levels regarding police brutality, societal discrimination, and school shootings. Four categories were created to indicate levels of each concern variable over time (consistently low, decreased, increased, and consistently high). Associations with past-30-day cannabis, blunt, THC-oil, and cigarette use in 2019 were assessed. Separate models for each racial/ethnic category were used.

RESULTS

Among Hispanic participants, reporting consistently high concern about police brutality (vs. consistently low concern) was associated with higher odds to subsequently smoke cannabis (aOR = 1.69, 95% CI = 1.18-2.40), smoke blunts (aOR = 1.63, 95% CI = 1.11-2.39), and vape THC-oil (aOR = 1.67, 95% CI = 1.14-2.44). Hispanic participants who reported consistently high concern for societal discrimination also had higher odds (vs. consistently low concern) to subsequently smoke blunts (aOR = 1.54, 95% CI = 1.04-2.29) and vape THC-oil (aOR = 1.65, 95% CI = 1.12-2.43). Among NHW participants, increasing concern over school shootings (vs. consistently low concern) was associated with higher odds to subsequently smoke cannabis (aOR = 2.98, 95% CI = 1.08-7.70).

CONCLUSIONS

Concerns for police brutality, societal discrimination, and school shootings were associated with cannabis use especially among Hispanic participants. Providing Hispanic youth with healthy coping strategies may reduce cannabis use.

Psychotic-Like Experiences and Concurrent Substance Use Among People Who Use New Psychoactive Substances

New psychoactive substances (NPS) are a group of substances that mimic established drugs, e.g., cannabinoids, stimulants, and opioids. NPS use has been associated with psychotic-like experiences, but current research is limited. This study focused on NPS use and psychotic-like experiences in persons attending substance use services in South-West Finland. The primary aim was to evaluate if NPS use associates with psychotic-like experiences, and if the association is independent of comorbid psychotic illness. As a secondary aim, this study evaluated concurrent substance use among people who use NPS.

The study was based on a voluntary and anonymous survey administered on-site for people attending substance use services. The survey was conducted in 17 substance use service centers in South-West Finland in 2019, totaling 219 respondents. Information on substance use, service use due to psychotic episodes, and comorbid psychotic illness was collected. A validated PROD questionnaire was used for information on psychotic-like experiences.

In all, 17% of 219 participants (n = 38) reported NPS use. After adjustments with comorbid psychotic illness, age, and gender, NPS use associated with PROD-screen positivity, i.e., reporting at least three psychotic-like symptoms. NPS use also associated with service use due to substance-induced psychotic episodes, and extensive use of several substances.

In this study, NPS use associated with psychotic-like experiences independently of comorbid psychotic illness. However, as NPS use is also associated with heavy use of several substances, this study implicates concurrent substance use as a confounding factor when studying NPS use, which should be considered in future research.

Prevalence and hospital resource usage associated with substance use disorder among hospitalized adolescents in the United States

We sought to determine common characteristics of SUD-related hospitalizations and patterns of discharge diagnoses among adolescents in the United States. Using the 2016 KID, a cross-sectional study was conducted to identify discharge records associated with ICD-10-CM diagnostic codes for SUD. Adolescents between the ages of 13 and 19 were included. SUD and non-SUD groups were compared using the Student's t-test for continuous variables and the χ2 test for categorical variables. A total of 6.7 million hospital discharges were analyzed. A uniform and a standardized coding system were used to identify cases. Subgroup comparative analysis for length of stay, hospital charge, and common discharge diagnoses was performed. A weighted estimate of 94,732 adolescents associated with SUD was discharged from the U.S. hospitals during the study year. Teens with SUD accounted for 510,268 days of inpatient days in the U.S. community hospitals accounting for a total charge of $3,070,948,580. The average LOS for all SUD teens in the U.S. was 5.4 days with a mean charge per discharge of $32,754, indicating higher LOS but a significantly lower mean charge compared to non-SUD teens (4.1 days; $39,657). In 2016, more than 88% of SUD patients had ≥ 3 diagnoses compared to non-SUD patients (76%) (P < 0.0001 for all). The most frequently observed diagnosis associated with teens with SUD was psychoses, depressive neuroses, and alcohol use disorder. With one in ten teenagers found with an SUD, early substance initiation still appears to be an important public health issue. Unfortunately, the health and economic impact of substance use in adolescence on society are huge requiring effective strategies targeted to this population. The concerning data and literature identify a significant need to address prevention, treatment, and recovery services for adolescents throughout the United States.

Neurobehavioral risk factors influence prevalence and severity of hazardous substance use in youth at genetic and clinical high risk for psychosis

Background

Elevated rates of alcohol, tobacco, and cannabis use are observed in both patients with psychotic disorders and individuals at clinical high risk for psychosis (CHR-P), and strong genetic associations exist between substance use disorders and schizophrenia. While individuals with 22q11.2 deletion syndrome (22qDel) are at increased genetic risk for psychosis, initial evidence suggests that they have strikingly low rates of substance use. In the current study, we aimed to directly compare substance use patterns and their neurobehavioral correlates in genetic and clinical high-risk cohorts.

Methods

Data on substance use frequency and severity, clinical symptoms, and neurobehavioral measures were collected at baseline and at 12-month follow-up visits in two prospective longitudinal cohorts: participants included 89 22qDel carriers and 65 age and sex-matched typically developing (TD) controls (40.67% male, Mage = 19.26 ± 7.84 years) and 1,288 CHR-P youth and 371 matched TD controls from the North American Prodrome Longitudinal Study-2 and 3 (55.74% male; Mage = 18.71 ± 4.27 years). Data were analyzed both cross-sectionally and longitudinally using linear mixed effects models.

Results

Controlling for age, sex, and site, CHR-P individuals had significantly elevated rates of tobacco, alcohol, and cannabis use relative to TD controls, whereas 22qDel had significantly lower rates. Increased substance use in CHR-P individuals was associated with increased psychosis symptom severity, dysphoric mood, social functioning, and IQ, while higher social anhedonia was associated with lower substance use across all domains at baseline. These patterns persisted when we investigated these relationships longitudinally over one-year. CHR-P youth exhibited significantly increased positive psychosis symptoms, dysphoric mood, social functioning, social anhedonia, and IQ compared to 22qDel carriers, and lower rates of autism spectrum disorder (ASD) compared to 22qDel carriers, both at baseline and at 1 year follow-up.

Conclusion

Individuals at genetic and CHR-P have strikingly different patterns of substance use. Factors such as increased neurodevelopmental symptoms (lower IQ, higher rates of ASD) and poorer social functioning in 22qDel may help explain this distinction from substance use patterns observed in CHR-P individuals.

Adolescents and youths' opinions about the factors associated with cannabis use: a qualitative study based on the I-Change model

BACKGROUND

To learn about the experiences and opinions of adolescent non-consumers and regular cannabis users about cannabis use and the factors that determine its use, using the I-Change explanatory model as a basis.

METHODS

Qualitative methodology with a content analysis was used. Focus groups were conducted with adolescents who were non-regular cannabis users (those who had not tried cannabis or had only experimented with it before) and semi-structured interviews were conducted with adolescent and young adult in recovery who were in a detoxification program. A deductive analysis of the audio-recorded and transcribed interviews was performed, using the domains of the I-Change Model as a reference.

RESULTS

Personal problems, social problems or family problems can lead to cannabis use. There was a lack of knowledge and low risk perception about consumption of this drug. There are other factors that influence consumption, the perception of advantages, such as the feeling of freedom and the influence of the peer group. The consumption of this substance in girls is changing, becoming more and more equal to that of boys. The family has an important role to play in preventing drug use.

CONCLUSION

Knowledge of these factors is of vital importance as a prior step to the development of efficient intervention measures adjusted to the needs identified and the characteristics of the population.

Independent contribution of polygenic risk for schizophrenia and cannabis use in predicting psychotic-like experiences in young adulthood: testing gene × environment moderation and mediation

BACKGROUND

It has not yet been determined if the commonly reported cannabis-psychosis association is limited to individuals with pre-existing genetic risk for psychotic disorders.

METHODS

We examined whether the relationship between polygenic risk score for schizophrenia (PRS-Sz) and psychotic-like experiences (PLEs), as measured by the Community Assessment of Psychic Experiences-42 (CAPE-42) questionnaire, is mediated or moderated by lifetime cannabis use at 16 years of age in 1740 of the individuals of the European IMAGEN cohort. Secondary analysis examined the relationships between lifetime cannabis use, PRS-Sz and the various sub-scales of the CAPE-42. Sensitivity analyses including covariates, including a PRS for cannabis use, were conducted and results were replicated using data from 1223 individuals in the Dutch Utrecht cannabis cohort.

RESULTS

PRS-Sz significantly predicted cannabis use (p = 0.027) and PLE (p = 0.004) in the IMAGEN cohort. In the full model, considering PRS-Sz and covariates, cannabis use was also significantly associated with PLE in IMAGEN (p = 0.007). Results remained consistent in the Utrecht cohort and through sensitivity analyses. Nevertheless, there was no evidence of a mediation or moderation effects.

CONCLUSIONS

These results suggest that cannabis use remains a risk factor for PLEs, over and above genetic vulnerability for schizophrenia. This research does not support the notion that the cannabis-psychosis link is limited to individuals who are genetically predisposed to psychosis and suggests a need for research focusing on cannabis-related processes in psychosis that cannot be explained by genetic vulnerability.

An Individuality of Response to Cannabinoids: Challenges in Safety and Efficacy of Cannabis Products

Since legalization, cannabis/marijuana has been gaining considerable attention as a functional ingredient in food. ∆-9 tetrahydrocannabinol (THC), cannabidiol (CBD), and other cannabinoids are key bioactive compounds with health benefits. The oral consumption of cannabis transports much less hazardous chemicals than smoking. Nevertheless, the response to cannabis is biphasically dose-dependent (hormesis; a low-dose stimulation and a high-dose inhibition) with wide individuality in responses. Thus, the exact same dose and preparation of cannabis may be beneficial for some but toxic to others. The purpose of this review is to highlight the concept of individual variations in response to cannabinoids, which leads to the challenge of establishing standard safe doses of cannabis products for the general population. The mechanisms of actions, acute and chronic toxicities, and factors affecting responses to cannabis products are updated. Based on the literature review, we found that the response to cannabis products depends on exposure factors (delivery route, duration, frequency, and interactions with food and drugs), individual factors (age, sex), and susceptibility factors (genetic polymorphisms of cannabinoid receptor gene, N-acylethanolamine-hydrolyzing enzymes, THC-metabolizing enzymes, and epigenetic regulations). Owing to the individuality of responses, the safest way to use cannabis-containing food products is to start low, go slow, and stay low.

Consensus paper of the WFSBP task force on cannabis, cannabinoids and psychosis

OBJECTIVES

The liberalisation of cannabis laws, the increasing availability and potency of cannabis has renewed concern about the risk of psychosis with cannabis.

METHODS

The objective of the WFSBP task force was to review the literature about this relationship.

RESULTS

Converging lines of evidence suggest that exposure to cannabis increases the risk for psychoses ranging from transient psychotic states to chronic recurrent psychosis. The greater the dose, and the earlier the age of exposure, the greater the risk. For some psychosis outcomes, the evidence supports some of the criteria of causality. However, alternate explanations including reverse causality and confounders cannot be conclusively excluded. Furthermore, cannabis is neither necessary nor sufficient to cause psychosis. More likely it is one of the multiple causal components. In those with established psychosis, cannabis has a negative impact on the course and expression of the illness. Emerging evidence also suggests alterations in the endocannabinoid system in psychotic disorders.

CONCLUSIONS

Given that exposure to cannabis and cannabinoids is modifiable, delaying or eliminating exposure to cannabis or cannabinoids, could potentially impact the rates of psychosis related to cannabis, especially in those who are at high risk for developing the disorder.

Cannabinoid Poisoning-Related Emergency Department Visits and Inpatient Hospitalizations in Kentucky, 2017 to 2019

Background and objectives: Cannabis is the most used federally illicit substance. Due to widespread medicinal use and state-level legalization, public perceptions of cannabis have shifted toward the assumption that cannabis is safe. However, cannabinoids can cause adverse medical complications that may lead people to seek treatment. This study characterized cannabinoid poisoning-related medical encounters, poisoning involving cannabinoids and other psychoactive substances, and cannabinoid poisoning-related cardiac complications. Methods: Administrative billing data for emergency department visits and inpatient hospitalizations in acute care facilities with a discharge date from January 1, 2017 to December 31, 2019 were used to characterize cannabinoid poisoning events in Kentucky, identified by ICD-10-CM diagnosis code T40.7X. Results: There were 1,490 encounters of cannabinoid poisoning; patients were primarily non-Hispanic White males, ages 15-44, who had Medicaid and lived in a metropolitan area. Of those, 31.21% involved poisoning with a second psychoactive substance, primarily stimulants and/or opioids, and 17.72% experienced a cardiac complication. Cannabinoid-polydrug poisoning was associated with inpatient treatment (χ2=199.18, p < 0.001) and cardiac complications (χ2=4.58, p < 0.001). Discussion and Conclusions: These results are consistent with other state-level data. Patients who were diagnosed with cannabis-polydrug poisoning, compared to cannabis alone poisoning, had greater odds of hospital admission and cardiac complications, and longer length of hospital stays. Scientific Significance: The health risks of cannabinoid use must be more broadly recognized, while timely and accurate data need to be shared to guide policies on cannabis access. Future research on cannabinoid poisoning should consider the involvement of other psychoactive drugs.

Cannabis and Intentional Self-injury: a Narrative Review

Purpose of Review

Observational studies assessing the association of cannabis use with subsequent intentional self-injury have reported mixed findings. Longitudinal studies examining the association of cannabis use with subsequent suicide death are notably rare. Our objective was to review longitudinal studies examining cannabis use and subsequent self-harm, suicide attempt, or suicide death.

Recent Findings

Few population-based studies have focused on self-harm with considerable variability across studies in how this outcome has been operationalized. Studies assessing the association between cannabis use and suicide attempt are equivocal in their conclusions and heterogenous in terms of samples utilized and assessment of confounding bias. The results of one meta-analysis were suggestive of dose dependency. For suicide death, the findings are inconsistent, and there is reason for concern of selection bias.

Summary

The existing evidence base on these associations is not yet rigorous enough to allow drawing conclusions on causality. However, cannabis might be seen as an adverse prognostic marker for intentional self-injury.

Cannabis use and attenuated positive and negative symptoms in youth at clinical high risk for psychosis

Cannabis use is more prevalent among youth at clinical high-risk (CHR) for psychosis than healthy controls (HC). There is mixed evidence as to whether cannabis use is associated with increased severity of attenuated psychotic symptoms (APS) or whether current cannabis use is associated with the transition to psychosis. This study aims to assess cannabis use differences between CHR youth and HC and the impact of cannabis use on APS, clinical status, and transition to psychosis. Participants were from the North American Prodrome Longitudinal Study-3, a prospective longitudinal study including 710 individuals, age 12-30, meeting criteria for a psychosis risk syndrome based on the Structured Interview for Psychosis-Risk Syndromes, and 96 HC. Cannabis use, frequency, and severity of use were assessed with the Alcohol Use Scale/Drug Use Scale. Current and past cannabis use disorders were assessed with the Structured Clinical Interview for DSM-5. Compared to HC, CHR individuals reported significantly increased lifetime cannabis use, during the past six months, and at baseline; greater frequency and severity of cannabis use; and increased prevalence of cannabis use disorder. Relative to CHR youth without cannabis use, CHR cannabis users had significantly higher ratings on baseline grandiosity and lower 12-months social anhedonia. Severity of cannabis was unrelated to clinical status at 2-years, and it did not differentiate CHR individuals who transitioned to psychosis from those who did not. However, a major limitation was that the current number of CHR cannabis users was small, and survival analyses resulted in a smaller power than the 80 % recommended.

A Review of Digital Interventions to Decrease Cannabis Use Among Patients With Comorbid Psychiatric Disorders

OBJECTIVE

Cannabis use disorder (CUD) is associated with an elevated risk for psychiatric disorders and symptoms, contributing to poor health outcomes and increased medical costs. Unfortunately, interventions that simultaneously address cannabis use and co-occurring psychiatric disorders are limited in availability. Targeted digital interventions to reduce cannabis use could be beneficial for patients with psychiatric disorders. Digital interventions could be easily disseminated and used in numerous clinical locations, including outpatient, inpatient, residential, and community psychiatric treatment settings.

METHODS

Literature on digital cannabis reduction interventions for persons with psychiatric disorders was examined between April 2021 and June 2021. Articles were obtained from PubMed and PsycINFO databases. English language randomized controlled trials (RCT), feasibility and acceptability studies, pilot studies, and published protocols were included.

RESULTS

There is significant evidence that digital interventions can effectively reduce cannabis use in general, non-clinical populations. However, there is less literature examining interventions for persons living with co-occurring psychiatric illness-most of which is tailored to patients living with chronic psychosis.

CONCLUSIONS

There is great need for accessible and tailored digital interventions for co-occurring CUD and psychiatric disorders.

Individuals with cannabis use are associated with widespread morphological alterations in the subregions of the amygdala, hippocampus, and pallidum

BACKGROUND

Cannabis is the most frequently used illicit drug worldwide. Although multiple structural MRI studies of individuals with cannabis use (CB) have been undertaken, the reports of the volume alterations in the amygdala, hippocampus, and pallidum are not consistent. This study aims to detect subregion-level morphological alterations, analyze the correlation areas with cannabis usage characteristics, and gain new insights into the neuro mechanisms of CB.

METHODS

By leveraging the novel surface-based subcortical morphometry method, 20 CB and 22 age- and sex-matched healthy controls (HC) were included to explore their volumetric and morphological differences in the three subcortical structures. Afterward, the correlation analysis between surface morphological eigenvalues and cannabis usage characteristics was performed.

RESULTS

Compared with volumetric measures, the surface-based subcortical morphometry method detected more significant global morphological deformations in the left amygdala, right hippocampus, and right pallidum (overall-p < 0.05, corrected). More obvious morphological alterations (atrophy or expansion) were observed in specific subregions (vertex-based p-value<0.05, uncorrected) of the three subcortical structures. Both positive and negative subregional correlation areas were reported by the correlation analysis.

CONCLUSIONS

The current study illuminated new pathophysiologic mechanisms in the amygdala, hippocampus, and pallidum at the subregion level, which may inform the subsequent smaller-scale CB research.

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.

Is early exposure to cannabis associated with bipolar disorder? Results from a Finnish birth cohort study

BACKGROUND AND AIMS

There are few longitudinal studies assessing the association of cannabis use and subsequent onset of bipolar disorder. We aimed to measure the association between early cannabis exposure and subsequent bipolar disorder.

DESIGN, SETTING AND PARTICIPANTS

Observational study linking a sample from the northern Finland birth cohort 1986 (n = 6325) to nation-wide register data to examine the association of life-time cannabis exposure at age 15/16 years and subsequent bipolar disorder until age 33 (until the end of 2018); 6325 individuals (48.8% males) were included in the analysis.

MEASUREMENTS

Cannabis exposure was measured via self-report. Bipolar disorder was measured via bipolar disorder-related diagnostic codes (ICD-10: F30.xx, F31.xx) collected from the Care Register for Health Care 2001-18, the Register of Primary Health Care Visits 2011-18, the medication reimbursement register of the Social Insurance Institution of Finland 2001-05 and the disability pensions of the Finnish Center for Pensions 2001-16. Potential confounders included demographic characteristics, parental psychiatric disorders, emotional and behavioral problems and other substance use.

FINDINGS

Three hundred and fifty-two adolescents (5.6%) reported any cannabis use until the age of 15-16 years. Of the whole sample, 66 (1.0%) were diagnosed with bipolar disorder. Adolescent cannabis use was associated with bipolar disorder [hazard ratio (HR) = 3.46; 95% confidence interval (CI) = 1.81-6.61]. This association remained statistically significant after adjusting for sex, family structure and parental psychiatric disorders (HR = 3.00; 95% CI = 1.47-6.13) and after further adjusting for adolescent emotional and behavioral problems (HR = 2.34; 95% CI = 1.11-4.94). Further adjustments for frequent alcohol intoxications, daily smoking and lifetime illicit drug use attenuated the associations to statistically non-significant.

CONCLUSIONS

In Finland, the positive association between early cannabis exposure and subsequent development of bipolar disorder appears to be confounded by other substance use.

Trajectories of adolescent psychotic-like experiences and early cannabis exposure: Results from a Finnish Birth Cohort Study

BACKGROUND

Longitudinal studies examining the effect of cannabis exposure (CE) on the prognosis of adolescents with psychotic-like experiences (PLEs) are scarce. We examined trajectories of mental health in adolescents with PLEs and cannabis exposure.

METHODS

The Northern Finland Birth Cohort 1986 (n = 6552) with linkage to nationwide register data was used. Information on lifetime cannabis exposure was collected when participants were aged 15/16. Register-based outcome data on diagnoses made in clinical practice were obtained until age 33. Logistic regression was used to study the association of PLE/CE patterns and subsequent psychiatric disorders. The group with neither PLEs nor CE was utilized as the reference group. Parental psychiatric disorders, family structure, sex, frequent alcohol intoxications, daily smoking and illicit substance use other than cannabis were adjusted for.

RESULTS

In all, 6552 subjects (49.2 % males) were included in analysis. PLEs with cannabis exposure were associated with any psychiatric disorder (OR = 2.59; 95 % CI 1.82-3.68), psychotic disorders (OR = 3.86; 95 % CI 1.83-8.11), mood disorders (OR 4.07; 95 % CI 2.74-6.04), depressive disorders (OR = 4.35; 95 % CI 2.93-6.48), anxiety disorders (OR = 2.06; 95 % CI 1.34-3.17) and substance use disorders (OR = 2.26; 95 % CI 1.13-4.50) compared to reference group. Effect sizes were greater for group with both PLEs and cannabis use than for group with PLEs only.

CONCLUSIONS

Early-onset cannabis use is an adverse prognostic marker for adolescents with PLEs after extensive confounder control including other substance use.

Safety and Efficacy of Medical Cannabis in Autism Spectrum Disorder Compared with Commonly Used Medications

Objective: The objective of this study was to evaluate the safety and efficacy of medications commonly used in autism spectrum disorder (ASD) and compare this to what current research has shown regarding medical cannabis use in this population. Methods: Searches were performed to collect information surrounding currently used medications and their safety and efficacy profiles, biologic plausibility of cannabis use for symptoms of ASD, and studies detailing cannabis' safety and efficacy profile for use in the ASD population. Results were used to compare medications to cannabis as a proposed treatment. Results: The heterogeneity of ASD produces great difficulties in finding appropriate treatment, leading to many medication changes or treatment trials throughout a patient's life. Commonly prescribed medications display varying levels of efficacy, safety, and tolerability between patients and symptoms targeted. Some of the most common side effects cited are also considered the most troubling symptoms associated with ASD; aggression, anxiety, irritability, and a negative effect on cognition, leading many patients to discontinue use as the side effects outweigh benefits. Recent case reports and retrospective studies have displayed the potential efficacy, safety, and tolerability of cannabidiol (CBD)-rich medical cannabis use for treating both core symptoms of ASD and many comorbid symptoms such as irritability and sleep problems. Studies have also identified circulating endocannabinoids as a possible biomarker for ASD, providing another possible method of diagnosis. Conclusions: Currently, there are no approved medications for the core symptoms of ASD and only two medications Food and Drug Administration approved for associated irritability. Prescribed medications for symptoms associated with ASD display varying levels of efficacy, safety, and tolerability among the heterogeneous ASD population. At the time of this study there are no published placebo-controlled trials of medical cannabis for ASD and the observational studies have limitations. CBD-rich medical cannabis seems to be an effective, tolerable, and relatively safe option for many symptoms associated with ASD, however, the long-term safety is unknown at this time.

Substance use in childhood and adolescence and its associations with quality of life and behavioral strengths and difficulties

BACKGROUND

Substance use in childhood and adolescence continues to be a current health concern. The aims of the present study were to identify trends in the use of alcohol, cigarettes, and cannabis in children and adolescents in the last 10 years and to assess associations between substance use and quality of life and behavioral strengths and difficulties.

METHODS

Substance use was examined in 1829 9- to 18-year-old German children and adolescents participating in the LIFE Child cohort study between 2011 and 2020. Quality of life was investigated using the KIDSCREEN-27 questionnaire. The Strength and Difficulties Questionnaire was used to assess behavioral strengths and difficulties. Associations were assessed using linear regression analyses. All effects were adjusted for age, gender, and family socio-economic status.

RESULTS

38.44% of participants reported drinking alcohol at least sometimes. Smoking (6.23%) and the use of cannabis (3.94%) were less frequent. While we observed no significant changes in smoking between 2011 and 2021, the consumption of cannabis and the frequent consumption of alcohol has increased in this time period. Cigarette and cannabis use were associated with additional symptoms of hyperactivity/inattention and reduced prosocial behavior. For all three substances, usage was associated with more conduct problems. We also found significant associations between substance use and a lower quality of life in the areas of physical wellbeing, psychological wellbeing, parent relation and autonomy, and school environment. One noteworthy finding was that cigarette consumption and frequent alcohol use were associated with higher quality of life in terms of social support/peer group relations. Some significant interactions between substance use and child age indicated that associations between substance use and quality of life or behavioral difficulties were stronger in younger than in older children.

CONCLUSIONS

The results show that quality of life and behavioral difficulties are associated with substance use and should be considered when developing or implementing preventive measures to counter substance use. Furthermore, the findings indicate that substance use can be accompanied by improved peer relations. Therefore, the influence of peers, especially of peers who use these substances, should not be underestimated.

Early onset psychosis and cannabis use: Prevalence, clinical presentation and influence of daily use

Most of the studies examining the impact of cannabis use in first episode psychosis (FEP) have been carried out in samples with adult-onset FEP. Data in persons with early onset psychosis (EOP) is scarce. The aims of the study were: To describe the prevalence of lifetime cannabis use, current use, and daily use in patients with EOP compared to healthy controls. To study the differences in clinical presentation between cannabis users and non-users. To examine the risk of presenting an EOP associated with cannabis use and the effect of doses and age of onset of use. An observational cross-sectional study was performed in 90 EOP cases and 62 healthy controls, aged between 7 and 17 years. Our results show a higher prevalence of lifetime use (p = 0002), current use (p < 0.001), and daily use (p < 0.001) in EOP cases in comparison with healthy controls. Regarding clinical presentation, we did not find significant differences in any subscale of the Positive and Negative Syndrome Scale (PANSS). Non-user patients presented more severe depressive symptoms (p = 0002) and worse social functioning than cannabis users (p = 0026). Compared with subjects who never used cannabis, the risk of an EOP was significantly higher for those with a lifetime use (OR = 2.88, p = 0.002)current use (O.R = 6.09, p < 0001), and especially in those with daily use (O.R = 42.77, p = <0001). We found a higher risk of EOP in patients that have used cannabis before 15 years of age. In conclusion, it is necessary to develop early- detection and specific treatment programs for adolescents with cannabis use.

Age of first alcohol intoxication and psychiatric disorders in young adulthood - A prospective birth cohort study

OBJECTIVE

Early onset of alcohol use is associated with an increased risk of substance use disorders (SUD), but few studies have examined associations with other psychiatric disorders. Our aim was to study the association between the age of first alcohol intoxication (AFI) and the risk of psychiatric disorders in a Finnish general population sample.

METHODS

We utilized a prospective, general population-based study, the Northern Finland Birth Cohort 1986. In all, 6,290 15-16-year old adolescents answered questions on AFI and were followed up until the age of 33 years for psychiatric disorders (any psychiatric disorder, psychosis, SUD, mood disorders and anxiety disorders) by using nationwide register linkage data. Cox-regression analysis with Hazard Ratios (HR, with 95% confidence intervals (CI)) was used to assess the risk of psychiatric disorders associated with AFI.

RESULTS

Statistically significant associations were observed between AFI and any psychiatric disorder, psychosis, SUDs, and mood disorders. After adjustments for other substance use, family structure, sex and parental psychiatric disorders, AFIs of 13-14 years and ≤12 years were associated with SUD (HR = 5.30; 95%CI 2.38-11.82 and HR = 6.49; 95%CI 2.51-16.80, respectively), while AFI ≤ 12 years was associated with any psychiatric disorder (HR = 1.59; 95%CI 1.26-2.02) and mood disorders (HR = 1.81; 95%CI 1.22-2.68). After further adjustments for Youth Self Report total scores, AFI ≤ 14 was associated with an increased risk of SUD and AFI ≤ 12 with an increased risk of any psychiatric disorder.

CONCLUSIONS

We found significant associations between the early age of first alcohol intoxication, later SUD and any psychiatric disorder in a general population sample. This further supports the need for preventive efforts to postpone the first instances of adolescent alcohol intoxication.

Environmental Risk Factors in Bipolar Disorder and Psychotic Depression: A Systematic Review and Meta-Analysis of Prospective Studies

OBJECTIVE

The aim of this systematic review and meta-analysis was to study the association between specific environmental risk factors (ERF) and later development of Bipolar disorder and Psychotic depression.

METHODS

A systematic search of prospective studies was conducted in MEDLINE, EMBASE and PsycINFO databases, and supplemented by hand searching, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (registration number: CRD42018092253). Selected ERF included: pre-/peri-natal factors-paternal age at birth, maternal infection, obstetric complications, perinatal stress; early childhood factors-urbanicity at birth, childhood infection, childhood adversity; later life factors-substance misuse, ethnic minority and migration, urbanicity later in life, stressful life events, and traumatic head injury. Pooled effect sizes of the association between these ERF and affective psychoses were calculated from systematically selected studies. When studies examining each ERF were insufficient for meta-analysis, results were presented narratively.

RESULTS

Forty-six studies were included for quantitative analyses among selected ERF for affective psychosis, with significant association found for paternal age >40 years (OR 1.17, 95%CI 1.12-1.23), early (OR 1.52, 95%CI 1.07-2.17) and late (OR 1.32, 95%CI 1.05-1.67) gestational age, childhood adversity (OR 1.33, 95%CI 1.18-1.50), substance misuse (OR 2.87, 95%CI 1.63-5.50), and being from an ethnic minority (OR 1.99, 95%CI 1.39-2.84).

CONCLUSIONS

These results suggest some shared environmental load between non-affective and affective psychosis, implying generalized risks for psychosis rather than for specific diagnostic categories. Nonetheless, published studies for some ERF in the affective psychoses are scarce, and further longitudinal studies are needed.

The Behavioral Sequelae of Cannabis Use in Healthy People: A Systematic Review

Background: Cannabis is known to have a broad range of effects on behavior, including experiencing a "high" and tranquility/relaxation. However, there are several adverse behavioral sequalae that can arise from cannabis use, depending on frequency of use, potency (e.g., THC content), age of onset, and cumulative exposure. This systematic review examined evidence for cannabis-related adverse behavioral sequalae in otherwise healthy human subjects. Methods: Following PRISMA guidelines, we conducted a systematic review of cross-sectional and longitudinal studies from 1990 to 2020 that identified cannabis-related adverse behavioral outcomes in subjects without psychiatric and medical co-morbidities from PubMed and PsychInfo searches. Key search terms included "cannabis" OR "tetrahydrocannabinol" OR "cannabidiol" OR "marijuana" AND "anxiety" OR "depression" OR "psychosis" OR "schizophrenia" "OR "IQ" OR "memory" OR "attention" OR "impulsivity" OR "cognition" OR "education" OR "occupation". Results: Our search detected a total of 2,870 studies, from which we extracted 124 relevant studies from the literature on cannabis effects in the non-clinical population. Effects of cannabis on several behavioral sequelae including cognition, motivation, impulsivity, mood, anxiety, psychosis intelligence, and psychosocial functioning were identified. The preponderance of the evidence suggests that frequency of cannabis use, THC (but not CBD) content, age of onset, and cumulative cannabis exposure can all contribute to these adverse outcomes in individuals without a pre-existing medical condition or psychiatric disorder. The strongest evidence for the negative effects of cannabis are for psychosis and psychosocial functioning. Conclusions: Although more research is needed to determine risk factors for development of adverse behavioral sequelae of cannabis use, these findings underline the importance of understanding vulnerability to the adverse effects of cannabis, which has implications for prevention and treatment of problematic cannabis use.

Co-occurring mental disorder and substance use disorder in young people: aetiology, assessment and treatment

Dual diagnosis is one of several terms used to identify individuals diagnosed with a co-occurring mental disorder and substance use disorder. The existence of a dual diagnosis in adolescents is often associated with functional impairment in various life domains, causing physical health problems, relational conflicts, educational/vocational underachievement and legal problems. Dual diagnosis is difficult to treat and can result in tremendous economic burden on healthcare, education and justice systems. It is essential for clinicians caring for young people to be knowledgeable about dual diagnosis to ensure that it is identified early and treated. This article aims to provide an overview of dual diagnosis, increase its awareness and promote a realistic treatment approach.

Smoke and Mirrors: The Recreational Marijuana Debate

The increasingly widespread legalization of recreational marijuana should raise concerns regarding the societal and medical impact of its use. The relative cultural acceptance for its use should be counterbalanced with an honest and scientific review of the adverse impacts. This article provides a synopsis of recent studies that point to significant concerns from medical and psychiatric viewpoints.

Summary

With the increasing number of states that have legalized the use of recreational marijuana, concerns regarding its negative effects are necessary. There is growing scientific evidence that the use of marijuana for recreational purposes has a wide variety of negative health effects, both physical and psychiatric.

Marijuana and the hippocampus: A longitudinal study on the effects of marijuana on hippocampal subfields

The psychoactive effects of cannabis, one of the most commonly used narcotics, have been documented extensively. Despite multiple studies being undertaken, there have been only a few longitudinal studies investigating the effect of long term usage of cannabis on various subcortical structures. This study aims at looking deeper into the effects of long term usage of cannabis on different hippocampus subfields.² Participants were split into two groups, cannabis users and healthy controls. All the test subjects filled out the Cannabis Usage and Disorder Identification Test (CUDIT) and underwent T1-structural MRI scans twice, at a baseline and a followup 3 years later. The subfield volumes were measured using the software package Freesurfer with the LongitudinalHippocampalSubfields (v6.0) Module. Lifetime usage in grams was calculated for each participant until baseline and followup, independently, using linear interpolation. Usage of cannabis (lifetime consumption score) was correlated to increased volumes in certain subfields: the CA3 and CA4 in the right hemisphere and the presubiculum in both, the left and right hemispheres at baseline. Other tests including student's t-test and multivariate analysis of covariance were performed. Tests to understand the effects of varying consumption were also performed. Persistent usage of cannabis, however, did not result in atrophy of the subfields over time. Rather, there were lower growth rates observed in the healthy controls group as compared to that of the cannabis users in certain subfields.

Cannabis and the Developing Adolescent Brain

Purpose of Review

This review summarizes (1) recent trends in delta-9-tetrahydrocannabionol [THC] and cannabidiol (CBD) content in cannabis products, (2) neurobiological correlates of cannabis use on the developing adolescent brain, (3) effects of cannabis on psychiatric symptoms and daily functioning in youth (i.e., academic performance, cognition, sleep and driving), (4) cannabis products used to relieve or treat medical issues in youth, and (5) available treatments for cannabis use disorder in adolescence.

Recent findings

Despite marked increases in THC content and availability of cannabis, there has been a decline in perceived risk and an increase in use of THC extract products among youth in the United States. The primary psychiatric symptoms associated with cannabis use in youth are increased risk for addiction, depressive, and psychotic symptoms. Cannabis alters endocannabinoid system function which plays a central role in modulating the neurodevelopment of reward and stress systems. To date, few studies have examined neurobiological mechanisms underlying the psychiatric sequalae of cannabis exposure in youth. Adolescent cannabis exposure results in impaired cognition, sleep, and driving ability. There are very limited FDA-approved cannabinoid medications, none of them supporting their use for the treatment of psychiatric symptoms. Behavioral therapies are currently the mainstay of treating cannabis misuse, with no pharmacotherapies currently approved by the FDA for cannabis use disorder in youth.

Summary

Here, we summarize the most up-to-date knowledge on the neurobiological psychiatric, and daily function effects of the most commonly used cannabinoids, delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). We then review FDA approved medical use of cannabinoid treatments as well as pharmacological and psychological treatments for cannabis use disorder in youth. Our current understanding of the effects of cannabis on the developing brain and treatments for cannabis misuse in youth remain limited. Future research aimed at examining the neurobiological effects of cannabis, with objective measures of exposure, over the course of pediatric development and in relation to psychiatric symptoms are needed.

A Review of Cases of Marijuana and Violence

Marijuana is the most consumed illicit drug in the world, with over 192 million users. Due to the current legalization push of marijuana in the United States, there has been a lack of oversight regarding its public health policies, as marijuana advocates downplay the drug’s negative effects. This paper’s approach is from a public health perspective, focusing specifically on the cases of violence amongst some marijuana users. Here, we present 14 cases of violence with chronic marijuana users that highlight reoccurring consequences of: marijuana induced paranoia (exaggerated, unfounded distrust) and marijuana induced psychosis (radical personality change, loss of contact with reality). When individuals suffering from pre-existing medical conditions use marijuana in an attempt to alleviate their symptoms, ultimately this worsens their conditions over time. Although marijuana effects depend on the individual’s endocannabinoid receptors (which control behavioral functions, like aggression) and the potency level of tetrahydrocannabinol (THC) in the drug, scientifically documented links between certain marijuana users and violence do exist. Wider public awareness of the risks and side effects of marijuana, as well as a more prudent health policy, and government agency monitoring of the drug’s composition, creation, and distribution, are needed and recommended.

The Effectiveness of Cannabinoids in the Treatment of Posttraumatic Stress Disorder (PTSD): A Systematic Review

Objectives: Posttraumatic stress disorder (PTSD) is a potentially debilitating mental health problem. There has been a recent surge of interest regarding the use of cannabinoids in the treatment of PTSD. We therefore sought to systematically review and assess the quality of the clinical evidence of the effectiveness of cannabinoids for the treatment of PTSD. Method: We included all studies published until December 2018 where a patient has had PTSD diagnosed and had been prescribed or were using a cannabinoid for the purpose of reducing PTSD symptoms. Our primary outcome measure was the reduction in PTSD symptoms using a validated instrument. In the absence of randomized controlled trials, we included the next best available levels of evidence including observational and retrospective studies and case reports. We assessed risk of bias and quality using validated tools appropriate for the study design. Results: We included 10 studies in this review, of which only one study was a pilot randomized, double-blind, placebo-controlled, crossover clinical trial. Every identified study had medium to high risk of bias and was of low quality. We found that cannabinoids may decrease PTSD symptomology, in particular sleep disturbances and nightmares. Conclusions: Most studies to date are small and of low quality, with significant limitations to the study designs precluding any clinical recommendations about its use in routine clinical practice. Evidence that cannabinoids may help reduce global PTSD symptoms, sleep disturbances, and nightmares indicates that future well-controlled, randomized, double-blind clinical trials are highly warranted.PROSPERO registration number: 121646.

Is the Adolescent Brain at Greater Vulnerability to the Effects of Cannabis? A Narrative Review of the Evidence

Cannabis use during the critical neurodevelopmental period of adolescence, may lead to brain structural, functional, and histological alterations that may underpin some of the longer-term behavioral and psychological harms associated with it. The endocannabinoid system performs a key regulatory and homeostatic role, that undergoes developmental changes during adolescence making it potentially more susceptible to the effects of exposure to cannabis during adolescence. Here, we synthesize evidence from human studies of adolescent cannabis users showing alterations in cognitive performance as well as in brain structure and function with relevant preclinical evidence to summarize the current state of knowledge. We also focus on the limited evidence that speaks to the hypothesis that cannabis use during adolescence, may pose a greater risk than use during adulthood, identify gaps in current evidence and suggest directions for new research. Existing literature is consistent with the association of cannabis use during adolescence and neurological changes. Adolescence cannabis users show altered functional connectivity within known functional circuits, that may underlie inefficient recruitment of brain regions, as largely increased functional activation has been observed compared to controls. This disruption in some cases may contribute to the development of adverse mental health conditions; increasing the chances or accelerating the onset, of their development. Preclinical evidence, further supports disruption from cannabis use being specific to the developmental period. Future studies are required to better investigate adolescent cannabis use with more accuracy using better defined groups or longitudinal studies and examine the permanency of these changes following caseation of use. Furthermore, research is required to identify heritable risk factors to cannabis use. There is a need for caution when considering the therapeutic potential of cannabis for adolescence and particularly in public discourse leading to potential trivialization of possible harm from cannabis use in adolescence. Current evidence indicates that adolescence is a sensitive period during which cannabis use may result in adverse neurocognitive effects that appear to show a level of permanency into adulthood.

Brief interventions for cannabis use in emerging adults: A systematic review, meta-analysis, and evidence map

PURPOSE

This systematic review summarizes and critically appraises the existing literature on brief interventions (BIs) for cannabis use among emerging adults.

METHODS

Eligible BIs were operationalized as 1-2 sessions focused exclusively on cannabis use for samples with mean ages between 15 and 30. Outcomes related to cannabis use, other substance use, mental health, help-seeking, or functional status were included. Two independent reviewers screened a total of 3638 records, identifying 244 studies for full-text screening. In total, 32 BIs in 26 primary studies with 6318 participants were included.

RESULTS

Participants were typically not seeking treatment and using cannabis at least once a month. Most interventions were motivational, single sessions, and delivered in person. Few discussed concurrent psychiatric conditions. Pooling results at 1-3 months post-intervention, BIs compared to passive control slightly reduced symptoms of cannabis use disorder (SMD -0.14 [95% CI -0.26 to -0.01]) and increased the odds of abstinence (OR 1.73 [95% CI 1.13-2.66]). Other outcome results often favored BIs but were not significant. Results of studies comparing types of BIs (k = 8) or BIs to longer interventions (k = 1) are discussed narratively. Quality assessment suggested low to very low-quality evidence.

CONCLUSIONS

This review indicates that BIs targeting non-treatment seeking emerging adults result in significant reductions in symptoms of cannabis use disorder and an increased likelihood of cannabis abstinence, however evidence is of low quality.

The contribution of cannabis use to variation in the incidence of psychotic disorder across Europe (EU-GEI): a multicentre case-control study

BACKGROUND

Cannabis use is associated with increased risk of later psychotic disorder but whether it affects incidence of the disorder remains unclear. We aimed to identify patterns of cannabis use with the strongest effect on odds of psychotic disorder across Europe and explore whether differences in such patterns contribute to variations in the incidence rates of psychotic disorder.

METHODS

We included patients aged 18-64 years who presented to psychiatric services in 11 sites across Europe and Brazil with first-episode psychosis and recruited controls representative of the local populations. We applied adjusted logistic regression models to the data to estimate which patterns of cannabis use carried the highest odds for psychotic disorder. Using Europe-wide and national data on the expected concentration of Δ9-tetrahydrocannabinol (THC) in the different types of cannabis available across the sites, we divided the types of cannabis used by participants into two categories: low potency (THC <10%) and high potency (THC ≥10%). Assuming causality, we calculated the population attributable fractions (PAFs) for the patterns of cannabis use associated with the highest odds of psychosis and the correlation between such patterns and the incidence rates for psychotic disorder across the study sites.

FINDINGS

Between May 1, 2010, and April 1, 2015, we obtained data from 901 patients with first-episode psychosis across 11 sites and 1237 population controls from those same sites. Daily cannabis use was associated with increased odds of psychotic disorder compared with never users (adjusted odds ratio [OR] 3·2, 95% CI 2·2-4·1), increasing to nearly five-times increased odds for daily use of high-potency types of cannabis (4·8, 2·5-6·3). The PAFs calculated indicated that if high-potency cannabis were no longer available, 12·2% (95% CI 3·0-16·1) of cases of first-episode psychosis could be prevented across the 11 sites, rising to 30·3% (15·2-40·0) in London and 50·3% (27·4-66·0) in Amsterdam. The adjusted incident rates for psychotic disorder were positively correlated with the prevalence in controls across the 11 sites of use of high-potency cannabis (r = 0·7; p=0·0286) and daily use (r = 0·8; p=0·0109).

INTERPRETATION

Differences in frequency of daily cannabis use and in use of high-potency cannabis contributed to the striking variation in the incidence of psychotic disorder across the 11 studied sites. Given the increasing availability of high-potency cannabis, this has important implications for public health.

FUNDING SOURCE

Medical Research Council, the European Community's Seventh Framework Program grant, São Paulo Research Foundation, National Institute for Health Research (NIHR) Biomedical Research Centre (BRC) at South London and Maudsley NHS Foundation Trust and King's College London and the NIHR BRC at University College London, Wellcome Trust.

Serious psychological distress and daily cannabis use, 2008 to 2016: Potential implications for mental health?

BACKGROUND

Daily cannabis use is increasing in the United States (US). Yet, it is not known whether daily cannabis use is disproportionately common, or whether it has increased differentially over time, by mental health status. This study estimated the prevalence of daily cannabis use among adults in the US with and without past-month serious psychological distress (SPD; measured by the Kessler Psychological Distress Scale (K6)) in 2016 and estimated trends in daily cannabis use by past-30-day SPD status from 2008 to 2016.

METHODS

Data were drawn from adults age 18 and older in the 2008-2016 National Survey on Drug Use and Health (combined total analytic sample n = 356,413). Linear time trends of daily cannabis use, stratified by SPD status, were assessed using logistic regression models with continuous year as the predictor.

RESULTS

In 2016, past-month daily cannabis use was significantly more common among those with past-month SPD (8.07%), compared to those without past-month SPD (2.66%). Daily cannabis use increased significantly from 2008 to 2016 among those both with and without SPD although use among those with SPD was persistently higher than use among those without SPD over the time period studied.

CONCLUSIONS

Daily cannabis use is significantly more common among persons with serious psychological distress and is increasing in this group, as well as among those without. Given this increase and the high prevalence of cannabis use among those with SPD, it may be important to consider potential consequences of this increased use for those with mental health vulnerabilities.

Psychiatric research in the Northern Finland Birth Cohort 1986 - a systematic review

The Northern Finland Birth Cohort 1986 is a large population-based birth cohort, which aims to promote health and wellbeing of the population. In this paper, we systematically review the psychiatric research performed in the cohort until today, i.e. at the age of 32 years of the cohort (2018). We conducted a systematic literature search using the databases of PubMed and Scopus and complemented it with a manual search. We found a total of 94 articles, which were classified as examining ADHD, emotional and behavioural problems, psychosis risk or other studies relating to psychiatric subjects. The articles are mainly based on two large comprehensive follow-up studies of the cohort and several substudies. The studies have often used also nationwide register data. The studies have found several early predictors for the aforementioned psychiatric outcomes, such as problems at pregnancy and birth, family factors in childhood, physical inactivity and substance use in adolescence. There are also novel findings relating to brain imaging and cognition, for instance regarding familial risk of psychosis in relation to resting state functional MRI. The Northern Finland Birth Cohort 1986 has been utilised frequently in psychiatric research and future data collections are likely to lead to new scientifically important findings.

Abbreviations: attention deficit hyperactivity disorder (ADHD); magnetic resonance imaging (MRI)

Mental Health Issues and Substance Use in the United States: Pulling the Power Levers

BACKGROUND

Promising treatment avenues have been developed and studied that align well with the skills of psychiatric-mental health (PMH) nurses. The treatments are relationship-driven, nimble and accessible, and recovery-guided. They emphasize a whole-person approach with care delivered by a team of experts working in a contextually coordinated way.

AIMS

To describe the challenges facing the United States with regard to mental illness and substance use disorders and the ways in which PMH nurses can use their skills to mitigate these challenges.

METHOD

Published research and government reports were reviewed to obtain current mental health and substance use data.

RESULTS

The number of people not being treated for mental illnesses-particularly serious mental illness, major depressive episode, and suicidal thoughts-has not improved since 2009. Although inroads have been made in reducing the rate of smoking in the United States, we are facing an opioid crisis. There are limited data on marijuana use, but it is apparent that many Americans use cannabis routinely. According to the Substance Abuse and Mental Health Administration, approximately 44.7 million people need mental health treatment and 20.1 million Americans need substance use treatment, but only 10% to 30% receive it.

CONCLUSIONS

PMH nurses must take a leading role in retooling the therapeutic relationship and partnering with clients, families, and caregivers to improve the quality of life and well-being of those dealing with mental illness and substance use disorders. To accomplish this essential task, the PMH nursing workforce must be robust and distributed throughout the United States.

Cannabis acute use impacts symptoms and functionality in a cohort of antipsychotic naïve First Episode of Psychosis individuals

Introduction

Cannabis use increases the risk of developing psychosis, and subjects with psychosis are more likely to use cannabis. However, studies on the influence of cannabis on psychotic dimensions, response to treatment, and functional outcomes showed conflicting results. Such heterogeneity may be due the inclusion of patients who were already under treatment, and lack of specificity in evaluations. We investigated whether cannabis use yields distinct symptom profiles and functionality in a cohort of antipsychotic-naïve patients at first episode of psychosis (FEP).

Methods

This research is part of a prospective cohort study performed in Sao Paulo, Brazil. The baseline assessment was completed by 175 individuals, and 99 of them were reassessed in a ten-week follow up. We investigated the relationship between cannabis exposure variables (acute use, lifetime use and age at first use) and outcomes: symptom dimensions and functioning.

Results

Individuals who reported acute use of cannabis had higher excitement symptoms at baseline, higher excitement and positive response rates, but no significant differences at follow-up. Additionally, more days of cannabis use in the last month predicted worse functionality and clinical impression at baseline but not at follow-up.

Discussion

The acute use of cannabis influenced the clinical presentation at our FEP baseline assessment, but did not to influence symptoms or functional outcomes at 10-week follow-up. Additionally, acute cannabis users had a better response for excitement and positive symptoms. Higher excitement symptoms at presentation of FEP should raise concerns of possible acute use of cannabis. Longer follow-up times may elucidate whether the effects on functionality would be more evident later in disease development.

The challenges of 'medical cannabis' and mental health: a clinical perspective

The use of cannabis as a medicine has a long tradition in Western medicine. It has been seen as a viable option for the treatment of various neurological and psychiatric conditions, and recently there is again interest in the place of cannabinoids in the pharmacopoeia. What has become increasingly clear, however, is these benefits need to be weighed carefully against the potential difficulty associated with herbal cannabis and cannabinoid compounds for an individual's mental health. This challenges the use of cannabis as a medication and the regulation of its prescription.

Patterns of Substance Abuse in Offenders With Schizophrenia- Illness-Related or Criminal Life-Style?

Objective: The impact of substance abuse on violent behavior in patients suffering from schizophrenia is well-known. However, the association between the pattern of substance abuse and certain aspects of criminal behavior like the severity of offense, the previous history of violence and the age at onset of the criminal career is still unclear. Method: To assess the relationship between substance abuse, schizophrenia and violent behavior we examined healthy non-offenders; healthy offenders; non-offenders suffering from schizophrenia; and offenders suffering from schizophrenia, with respect to different patterns of substance abuse (none, alcohol only, illicit drugs only, and multiple substances). Results: Healthy offenders as well as offenders and non-offenders suffering from schizophrenia are characterized by increased rates of alcohol and illicit drug abuse. Especially multiple substance abuse appears to lower the threshold of aggression and illegal behavior. This effect is more pronounced in subjects suffering from schizophrenia. In both offender groups the abuse of psychoactive substances is associated with an earlier onset of the criminal career, but has no impact on the severity of the offenses. Conclusion: Our results point to the need for a differentiated view on the contribution of substance abuse to the criminality of subjects suffering from schizophrenia.