Cannabis and development of dual diagnoses: A literature review

Perturbation of 3D nuclear architecture, epigenomic aging and dysregulation, and cannabinoid synaptopathy reconfigures conceptualization of cannabinoid pathophysiology: part 2-Metabolome, immunome, synaptome

The second part of this paper builds upon and expands the epigenomic-aging perspective presented in Part 1 to describe the metabolomic and immunomic bases of the epigenomic-aging changes and then considers in some detail the application of these insights to neurotoxicity, neuronal epigenotoxicity, and synaptopathy. Cannabinoids are well-known to have bidirectional immunomodulatory activities on numerous parts of the immune system. Immune perturbations are well-known to impact the aging process, the epigenome, and intermediate metabolism. Cannabinoids also impact metabolism via many pathways. Metabolism directly impacts immune, genetic, and epigenetic processes. Synaptic activity, synaptic pruning, and, thus, the sculpting of neural circuits are based upon metabolic, immune, and epigenomic networks at the synapse, around the synapse, and in the cell body. Many neuropsychiatric disorders including depression, anxiety, schizophrenia, bipolar affective disorder, and autistic spectrum disorder have been linked with cannabis. Therefore, it is important to consider these features and their complex interrelationships in reaching a comprehensive understanding of cannabinoid dependence. Together these findings indicate that cannabinoid perturbations of the immunome and metabolome are important to consider alongside the well-recognized genomic and epigenomic perturbations and it is important to understand their interdependence and interconnectedness in reaching a comprehensive appreciation of the true nature of cannabinoid pathophysiology. For these reasons, a comprehensive appreciation of cannabinoid pathophysiology necessitates a coordinated multiomics investigation of cannabinoid genome-epigenome-transcriptome-metabolome-immunome, chromatin conformation, and 3D nuclear architecture which therefore form the proper mechanistic underpinning for major new and concerning epidemiological findings relating to cannabis exposure.

Perturbation of 3D nuclear architecture, epigenomic dysregulation and aging, and cannabinoid synaptopathy reconfigures conceptualization of cannabinoid pathophysiology: part 1-aging and epigenomics

Much recent attention has been directed toward the spatial organization of the cell nucleus and the manner in which three-dimensional topologically associated domains and transcription factories are epigenetically coordinated to precisely bring enhancers into close proximity with promoters to control gene expression. Twenty lines of evidence robustly implicate cannabinoid exposure with accelerated organismal and cellular aging. Aging has recently been shown to be caused by increased DNA breaks. These breaks rearrange and maldistribute the epigenomic machinery to weaken and reverse cellular differentiation, cause genome-wide DNA demethylation, reduce gene transcription, and lead to the inhibition of developmental pathways, which contribute to the progressive loss of function and chronic immune stimulation that characterize cellular aging. Both cell lineage-defining superenhancers and the superanchors that control them are weakened. Cannabis exposure phenocopies the elements of this process and reproduces DNA and chromatin breakages, reduces the DNA, RNA protein and histone synthesis, interferes with the epigenomic machinery controlling both DNA and histone modifications, induces general DNA hypomethylation, and epigenomically disrupts both the critical boundary elements and the cohesin motors that create chromatin loops. This pattern of widespread interference with developmental programs and relative cellular dedifferentiation (which is pro-oncogenic) is reinforced by cannabinoid impairment of intermediate metabolism (which locks in the stem cell-like hyper-replicative state) and cannabinoid immune stimulation (which perpetuates and increases aging and senescence programs, DNA damage, DNA hypomethylation, genomic instability, and oncogenesis), which together account for the diverse pattern of teratologic and carcinogenic outcomes reported in recent large epidemiologic studies in Europe, the USA, and elsewhere. It also accounts for the prominent aging phenotype observed clinically in long-term cannabis use disorder and the 20 characteristics of aging that it manifests. Increasing daily cannabis use, increasing use in pregnancy, and exponential dose-response effects heighten the epidemiologic and clinical urgency of these findings. Together, these findings indicate that cannabinoid genotoxicity and epigenotoxicity are prominent features of cannabis dependence and strongly indicate coordinated multiomics investigations of cannabinoid genome-epigenome-transcriptome-metabolome, chromatin conformation, and 3D nuclear architecture. Considering the well-established exponential dose-response relationships, the diversity of cannabinoids, and the multigenerational nature of the implications, great caution is warranted in community cannabinoid penetration.

Gender inequalities in the prevalence of low mood and related factors in schooled adolescents during the 2019-2020 school year: DESKcohort project

BACKGROUND

Mood disorders are the second most prevalent mental disorders in childhood and adolescence. Many undiagnosed people manifest subthreshold symptoms, like low mood, and present worse prognoses than asymptomatic healthy subjects. The aim of this study was to estimate the prevalence of low mood, gender inequalities, and associated factors, in 12- to 18-year-old adolescents in the rural and medium-sized urban areas of Central Catalonia during the 2019-2020 academic year.

METHODS

Cross-sectional study with data from a cohort of high-schooled students (2019-2020), with a convenience sample of 6428 adolescents from the Central region of Catalonia (48.3 % boys and 51.7 % girls). Prevalence of low mood was estimated by gender and exposure variables, and ratios were obtained using Poisson regression models, adjusting for several exposure variables one by one, and for all of them jointly.

RESULTS

The prevalence of low mood was 18.6 %, with statistically significant differences between genders (11.6 %, 95 % CI: 10.5-12.8 in boys and 25.1 %, 95 % CI: 23.7-26.6 in girls). Being an immigrant, dieting, and daily tobacco smoking were only associated with low mood in girls, whereas risky alcohol consumption was only associated in boys. Sexual violence was found to account for 36.2 % of low mood problems in girls.

LIMITATIONS

The main limitation of the study is its cross-sectional design, which means that no casual relationships can be extracted of this study.

CONCLUSIONS

The prevalence of low mood varies between the sexes, highlighting the importance of developing gender-specific interventions to reduce its incidence in young people, considering the factors associated with this condition.

Recommendations for Reducing the Risk of Cannabis Use-Related Adverse Psychosis Outcomes: A Public Mental Health-Oriented Evidence Review

Objective: Cannabis use is increasingly normalized; psychosis is a major adverse health outcome. We reviewed evidence on cannabis use-related risk factors for psychosis outcomes at different stages toward recommendations for risk reduction by individuals involved in cannabis use. Methods: We searched primary databases for pertinent literature/data 2016 onward, principally relying on reviews and high-quality studies which were narratively summarized and quality-graded; recommendations were developed by international expert consensus. Results: Genetic risks, and mental health/substance use problem histories elevate the risks for cannabis-related psychosis. Early age-of-use-onset, frequency-of-use, product composition (i.e., THC potency), use mode and other substance co-use all influence psychosis risks; the protective effects of CBD are uncertain. Continuous cannabis use may adversely affect psychosis-related treatment and medication effects. Risk factor combinations further amplify the odds of adverse psychosis outcomes. Conclusions: Reductions in the identified cannabis-related risks factors-short of abstinence-may decrease risks of related adverse psychosis outcomes, and thereby protect cannabis users' health.

Cannabis Use Disorder Treatment Preferences: A Pilot Survey in Current Users of Cannabis

OBJECTIVES

Highly effective treatments for cannabis use disorder (CUD) are lacking, and patient preferences have not been considered during treatment development. We therefore conducted an exploratory crowdsourced survey of individuals reporting current cannabis use and a willingness to cut down or quit their cannabis use, to determine their interest in various treatment aspects.

METHODS

Subjects (n = 63) were queried about their willingness to take medications as a function of type, route, and regimen and to participate in adherence monitoring. Subjects were also asked about their willingness to engage in behavioral/psychosocial interventions as a function of type, setting, and duration. Measures theorized to be associated with treatment preferences were also collected, including cannabis use variables, readiness to change, reduction or cessation goal, perceived cessation barriers, and medication use beliefs and behaviors.

RESULTS

Survey responses indicated that efforts to develop CUD medications should focus on nonsynthetic compounds administered orally or by mouth spray no more than once per day to maximize patient acceptance. Remote adherence monitoring and one-on-one outpatient behavioral treatment approaches, especially contingency management, are also anticipated to enhance participation. Most subjects indicated a preference to reduce their cannabis use rather than quit.

CONCLUSIONS

These data provide guidance for the development of CUD interventions based on the preferences of individuals interested in treatment for their cannabis use. Additional research is needed to confirm these results in a larger sample and determine if matching CUD patients with their preferred treatments improves success rates.

Epigenomic and Other Evidence for Cannabis-Induced Aging Contextualized in a Synthetic Epidemiologic Overview of Cannabinoid-Related Teratogenesis and Cannabinoid-Related Carcinogenesis

BACKGROUND

Twelve separate streams of empirical data make a strong case for cannabis-induced accelerated aging including hormonal, mitochondriopathic, cardiovascular, hepatotoxic, immunological, genotoxic, epigenotoxic, disruption of chromosomal physiology, congenital anomalies, cancers including inheritable tumorigenesis, telomerase inhibition and elevated mortality.

METHODS

Results from a recently published longitudinal epigenomic screen were analyzed with regard to the results of recent large epidemiological studies of the causal impacts of cannabis. We also integrate theoretical syntheses with prior studies into these combined epigenomic and epidemiological results.

RESULTS

Cannabis dependence not only recapitulates many of the key features of aging, but is characterized by both age-defining and age-generating illnesses including immunomodulation, hepatic inflammation, many psychiatric syndromes with a neuroinflammatory basis, genotoxicity and epigenotoxicity. DNA breaks, chromosomal breakage-fusion-bridge morphologies and likely cycles, and altered intergenerational DNA methylation and disruption of both the histone and tubulin codes in the context of increased clinical congenital anomalies, cancers and heritable tumors imply widespread disruption of the genome and epigenome. Modern epigenomic clocks indicate that, in cannabis-dependent patients, cannabis advances cellular DNA methylation age by 25-30% at age 30 years. Data have implications not only for somatic but also stem cell and germ line tissues including post-fertilization zygotes. This effect is likely increases with the square of chronological age.

CONCLUSION

Recent epigenomic studies of cannabis exposure provide many explanations for the broad spectrum of cannabis-related teratogenicity and carcinogenicity and appear to account for many epidemiologically observed findings. Further research is indicated on the role of cannabinoids in the aging process both developmentally and longitudinally, from stem cell to germ cell to blastocystoids to embryoid bodies and beyond.

Cannabis Use and the Development of Depression in Adolescents: Is There an Established Linear Relationship Between the Two?

The period of adolescence is a stage during which individuals experience several physical and psychological changes which increase their vulnerabilities to environmental influences. Cannabis exposure is one environmental factor that may put their health at risk. Various research agree that a connection exists between the onset of depression and cannabis use. Cannabis can affect the adolescents’ brain, making them susceptible to depression. Depression is a disorder that manifests in a myriad of ways that can be detrimental to individuals. This problem is not only confined to the individuals themselves, but it is also a societal problem. The relationship that exists between cannabis use and depression is an extremely complex one. This study’s main objective is to review previously conducted research regarding the association between cannabis use and depression in adolescents.

Medical conditions of primary care patients with documented cannabis use and cannabis use disorder in electronic health records: a case control study from an academic health system in a medical marijuana state

BACKGROUND

Approximately 3.8% of adults worldwide have used cannabis in the past year. Understanding how cannabis use is associated with other health conditions is crucial for healthcare providers seeking to understand the needs of their patients, and for health policymakers. This paper analyzes the relationship between documented cannabis use disorders (CUD), cannabis use (CU) and other health diagnoses among primary care patients during a time when medical use of marijuana was permitted by state law in California, United States of America.

METHODS

The study utilized primary care electronic health record (EHR) data from an academic health system, using a case-control design to compare diagnoses among individuals with CUD/CU to those of matched controls, and those of individuals with CUD diagnoses with individuals who had CU otherwise documented. Associations of documented CU and CUD with general medical conditions and health conditions associated with cannabis use (both medical and behavioral) were analyzed using conditional logistic regression.

RESULTS

Of 1,047,463 patients with ambulatory encounters from 2013-2017, 729 (0.06%) had CUD diagnoses and 3,731 (0.36%) had CU documented in their EHR. Patients with documented CUD and CU patients had significantly (p < 0.01) higher odds of most medical and behavioral diagnoses analyzed. Compared to matched controls, CUD-documented patients had highest odds of other substance use disorders (OR = 21.44: 95% CI 9.43-48.73), any mental health disorder (OR = 6.99; 95% CI 5.03-9.70) social anxiety disorder (OR = 13.03; 95% CI 2.18-77.94), HIV/AIDS (OR = 7.88: 95% CI 2.58-24.08), post-traumatic stress disorder (OR = 7.74: 95% CI 2.66-22.51); depression (OR = 7.01: 95% CI 4,79-10.27), and bipolar disorder (OR = 6.49: 95% CI 2.90-14.52). Compared to matched controls, CU-documented patients had highest odds of other substance use disorders (OR = 3.64; 95% CI 2.53-5.25) and post-traumatic stress disorder (OR = 3.41; 95% CI 2.53-5.25). CUD-documented patients were significantly more likely than CU-documented patients to have HIV/AIDS (OR = 6.70; 95% CI 2.10-21.39), other substance use disorder (OR = 5.88; 95% CI 2.42-14.22), depression (OR = 2.85; 95% CI 1.90-4.26), and anxiety (OR = 2.19: 95% CI 1.57-3.05) diagnoses.

CONCLUSION

The prevalence of CUD and CU notation in EHR data from an academic health system was low, highlighting the need for improved screening in primary care. CUD and CU documentation were associated with increased risk for many health conditions, with the most elevated risk for behavioral health disorders and HIV/AIDS (among CUD-documented, but not CU-documented patients). Given the strong associations of CUD and CU documentation with health problems, it is important for healthcare providers to be prepared to identify CU and CUD, discuss the pros and cons of cannabis use with patients thoughtfully and empathically, and address cannabis-related comorbidities among these patients.

Gender Differences in Dual Diagnoses Associated with Cannabis Use: A Review

Gender differences in psychiatric disorders and drug use are well known. Cannabis is the most widely used illegal drug among young people. In recent years, its use has been related to the development of psychiatric pathologies; however, few studies have incorporated the gender perspective as of yet. The present work analyses the literature to determine the existence of gender differences in the development of psychotic, depressive and anxious symptoms associated with cannabis use. First, we describe cannabis misuse and its consequences, paying special attention to adolescent subjects. Second, the main gender differences in psychiatric disorders, such as psychosis, depression, anxiety and cannabis use disorders, are enumerated. Subsequently, we discuss the studies that have evaluated gender differences in the association between cannabis use and the appearance of psychotic, depressive and anxious symptoms; moreover, we consider the possible explanations for the identified gender differences. In conclusion, the studies referred to in this review reveal the existence of gender differences in psychiatric symptoms associated with cannabis use, although the direction of such differences is not always clear. Future research is necessary to discern the causal relationship between cannabis use and the development of psychiatric symptoms, as well as the gender differences found.

Predicting Self-Medication with Cannabis in Young Adults with Hazardous Cannabis Use

Using cannabis to reduce psychological and physical distress, referred to as self-medication, is a significant risk factor for cannabis use disorder. To better understand this high-risk behavior, a sample of 290 young adults (ages 18–25; 45.6% female) were recruited from two U.S. universities in January and February of 2020 to complete a survey about their cannabis use and self-medication. Results: seventy-six percent endorsed using cannabis to reduce problems such as anxiety, sleep, depression, pain, loneliness, social discomfort, and concentration. When predicting reasons for self-medication with cannabis, logistic regression models showed that lower CUDIT-R scores, experiencing withdrawal, living in a state where cannabis was illegal, and being female were all associated with higher rates of self-medication. Withdrawal symptoms were tested to predict self-medication with cannabis, and only insomnia and loss of appetite were significant predictors. To further explore why young adults self-medicate, each of the original predictors were regressed on seven specified reasons for self-medication. Young adults experiencing withdrawal were more likely to self-medicate for pain. Participants living where cannabis is legal were less likely to self-medicate for anxiety and depression. Living where cannabis is illegal also significantly predicted self-medicating for social discomfort—though the overall model predicting social discomfort was statistically non-significant. Finally, female participants were more likely to self-medicate for anxiety. These results suggest widespread self-medication among young adults with likely CUD and underscore the complexity of their cannabis use. The findings have implications for understanding why young adults use cannabis in relation to psychological and physical distress and for accurately treating young adults with cannabis use disorder.

Substance Use among Youth in Community and Residential Mental Health Care Facilities in Ontario, Canada

There is a need to improve the integration of substance use and mental health care for children and youth. This study examines risk and protective factors for substance use among youth with mental health conditions who received community-based or residential care services between 2012–2020 in Ontario, Canada. In this study, a cross-sectional design was used to examine patterns and factors associated with substance use among youth (12–18 years) assessed in the community (n = 47,418) and residential (n = 700) mental health care facilities in Ontario, Canada. Youth were assessed with the interRAI Child and Youth Mental Health Assessment (ChYMH). Substance use is identified by any substance use (including alcohol) 14 to 30 days prior to assessment. Logistic regression with generalized estimating equations was used to examine clinical, psychosocial, and environmental factors associated with substance use. This study shows that 22.3% of youth reported the use of substances in the community settings and 37% in residential settings. Older age group (Youth older than 16 years), being a victim of abuse, having experienced self-injurious ideation/attempt, being at risk of disrupted education, and having a parent/caregiver with addiction or substance use disorder were significantly associated with substance use. Several factors reduced the risk of substance use, including being a female, having anxiety symptoms, and having cognition problems. In conclusion, the study found that individual and parental factors increase youth’s risk of substance use, highlighting the importance of a holistic approach that includes consideration of social and biological risk factors to prevention/risk reduction, risk assessment, management, and recovery.

Are Patients with Schizophrenia Reliably Reporting their Cannabis Use? An African Cross-sectional Study

BACKGROUND

Most studies of the prevalence of cannabis use among patients with schizophrenia used a self-report as declared by the patient himself. We hypothesize that patients with schizophrenia did not tell the truth and might underreport their use for many reasons to be discussed later. Indeed, the under-report of cannabis use among these patients can affect the effectiveness of their treatment.

AIMS

To assess the degree of agreement between the prevalence values obtained from patients' reports and the results of the toxicological tests.

METHODS

A cross-sectional study was carried out on 403 patients with schizophrenia. A sociodemographic, psychiatric history and illicit drug use profile was performed for each patient. We assessed the patients with the Positive and Negative Syndrome Scale (PANSS), Calgary Depression score (CDSS), Barratt Impulsiveness Score (BIS-10) and Medication Adherence Rating Scale (MARS). The consumption of cannabis used was confirmed with MINI International Neuropsychiatric Interview (MINI-DSM IV) and using toxicological analysis.

RESULTS

Among the 403 patients who consented to give their urine samples, 49.1% (198/403) tested positive for cannabis, and 41.41% (82/198) underreported their use. The sensitivity and specificity of the questionnaire were 0.58 and 0.74. Based on the comparison between sociodemographic and psychiatric history data of patients who self-report and underreport their cannabis use, no significant difference was observed except for the duration of cannabis use and the score on the medication adherence scale. Moreover, it was found that impulsivity, PANSS score, CDSS score, and the type of schizophrenia are not involved in predicting the underreporting of cannabis use.

CONCLUSION

The rate of patients who under-report cannabis use is important. Therefore, toxicological analysis is becoming relevant for identifying drug use among schizophrenic patients and in the addictive comorbidity research field.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Prevalence and associated factors of cannabis consumption in medical students: the BOURBON nationwide study

France has been identified with one of the highest rates of cannabis consumption of Western European countries. Yet we lack data in medical students who are at risk of addictive behavior. The objective of the study is to determine the prevalence of cannabis consumption and cannabis use disorder (CUD) among French medical students and their association with psychotropic drug consumption and psychosocial factors. Medical students were recruited from 35 French universities of medicine through administration mailing lists and social networks, between December 2016 and May 2017. Cannabis consumption was self-declared by anonymous questionnaire and CUD was defined by a Cannabis Abuse Screening Test (CAST) score ≥ 3. 10,985 medical students with a mean age of 21.8 years (± 3.3) were included, 32% of which were men. Overall, 1642 [14.9 (14.3; 15.6)%] reported cannabis consumption and 622 [5.7 (5.2; 6.1)%] students were identified with CUD at screening. Men were at two-time higher risk of cannabis consumption and three-time higher risk of CUD (22.4% and 10.6% for men vs. 11.5% and 3.4%, respectively, for women). In multivariate analyses, men sex, alcohol use disorder, tobacco smoking, parents' divorce, and history of physical assault and lower rates of lower rates of ≥ 40 weekly worked hours were identified as common associated factors for cannabis consumption and CUD. Hypnotic consumption, psychiatric follow-up, and history of sexual assault were identified as factors associated specifically with CUD, suggesting that these factors were associated with more severe cannabis consumption. Only 17% of students identified with CUD reported a psychiatric follow-up. Altogether, these results suggest that health policies should target cannabis consumption in medical students that is frequent, especially in men, with low rates of psychiatric follow-up. We have identified psychological factors and increased hypnotic drug consumption in CUD participants suggesting that psychiatric follow-up should be systematically proposed to this group.

"Is medical cannabis safe for my patients?" A practical review of cannabis safety considerations

Medical cannabis use is increasing worldwide. Clinicians are commonly asked by patients to provide guidance on its safety and efficacy. Although there has been an increase in research on the role of medical cannabis for a number of different conditions, we found that there was a paucity of clear safety guidance on its use. We aim to address this issue by answering two pertinent clinician safety questions: 1 Can medical cannabis be safely used in this patient? 2. What strategies can be used to ensure that any harms from medical cannabis are mitigated? To address these questions, we reviewed available evidence and provided expert clinical opinion to summarize the fundamental components for evaluating medical cannabis safety and strategies to reduce risk from its use. Our review resulted in a safety-focused framework for medical cannabis initiation and utilization. We provide clear recommendations for patients being considered for cannabis (e.g. precautions, contraindications and drug interactions). Risk mitigation strategies such as appropriate chemovar (strain) selection, routes of administration, and dosing are reviewed. As with any other pharmacotherapy, we review the key components of monitoring and address potential issues that may arise while using medical cannabis. We propose a structured assessment and monitoring strategy that can be used by clinicians recommending cannabis (CRC) to guide patients through each step of their cannabis journey. This framework can be used to ensure that medical cannabis utilization is associated with the lowest possible risk to the patient.

Symptoms of distress during the COVID-19 pandemic in the United States

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in the United States can negatively impact physical and mental health. Participants were asked about psychosocial factors associated with experiencing symptoms of distress via surveys distributed on Social Media. Results showed that younger age, unemployment/losing wages/job, worse perceived general health (compared to excellent health) and recent smoking were consistently associated with increased odds of feelings of depression and anxiety. Further, females (aOR=1.96, 95% CI: 1.24, 3.11) was associated with increased odds of feelings of depression. Findings reinforce a call for widespread, targeted prevention and treatment interventions for particular groups.

Down and High: Reflections Regarding Depression and Cannabis

In light of the recent changes in the legal status of cannabis in Canada, the understanding of the potential impact of the use of cannabis by individuals suffering from depression is increasingly considered as being important. It is fundamental that we look into the existing literature to examine the influence of cannabis on psychiatric conditions, including mood disorders. In this article, we will explore the relationship that exists between depression and cannabis. We will examine the impact of cannabis on the onset and course of depression, and its treatment. We have undertaken a wide-ranging review of the literature in order to address these questions. The evidence from longitudinal studies suggest that there is a bidirectional relationship between cannabis use and depression, such that cannabis use increases the risk for depression and vice-versa. This risk is possibly higher in heavy users having initiated their consumption in early adolescence. Clinical evidence also suggests that cannabis use is associated with a worse prognosis in individuals with major depressive disorder. The link with suicide remains controversial. Moreover, there is insufficient data to determine the impact of cannabis use on cognition in individuals with major depression disorder. Preliminary evidence suggesting that the endogenous cannabinoid system is involved in the pathophysiology of depression. This will need to be confirmed in future positron emission tomography studies. Randomized controlled trials are needed to investigate the potential efficacy of motivational interviewing and/or cognitive behavioral therapy for the treatment of cannabis use disorder in individuals with major depressive major disorder. Finally, although there is preclinical evidence suggesting that cannabidiol has antidepressant properties, randomized controlled trials will need to properly investigate this possibility in humans.

Psychiatric Comorbidity and Addiction Severity Differences in Patients With ADHD Seeking Treatment for Cannabis or Cocaine Use Disorders

Objective: The objective of this study was to compare psychiatric comorbidity and consumption-related variables in ADHD patients seeking treatment for cocaine, cannabis, or both. Method: Assessment was conducted using European Addiction Severity Index (EuropASI), Conners' Adult ADHD Diagnostic Interview (CAADID), Structured Clinical Interview for DSM Disorders (SCID), Adult Self-Report Scale (ASRS), Wender Utah Rating Scale (WURS), Barratt Impulsiveness Scale-11 (BIS-11), and FIDI, with statistical analyses of analysis of variance (ANOVA), Student's t test, chi-square test, and multinomial regression model. Results: In total, 1,538 patients with substance use disorder (SUD) were evaluated for ADHD; 239 (15.5%) had ADHD, with cannabis 41, cannabis/cocaine 36, and cocaine 74. Men represented 80%, with mean age of 32.9 ± 10 years. Significant variables were-in bivariate analysis-more years of cannabis use in cannabis group and younger age for cocaine use disorder in cannabis/cocaine group, and-in multivariate analysis-lifetime anxiety disorder and younger age at onset of any SUD in cannabis group and working affected scale in cannabis and polysubstance use in cannabis/cocaine group. Conclusion: Groups with cannabis use had higher severity. ADHD features were similar in all groups. The assessment of ADHD and comorbid disorders is important.

Psychotic disorder and cannabis use: Canadian hospitalization trends, 2006-2015

INTRODUCTION

Given the recent and impending changes to the legal status of nonmedical cannabis use in Canada, understanding the effects of cannabis use on the health care system is important for evaluating the impact of policy change. The aim of this study was to examine pre-legalization trends in hospitalizations for mental and behavioural disorders due to the use of cannabis, according to demographics factors and clinical conditions.

METHODS

We assessed the total number of inpatient hospitalizations for psychiatric conditions with a primary diagnosis of a mental or behavioural disorder due to cannabis use (ICD-10-CA code F12) from the Hospital Mental Health Database for ten years spanning 2006 to 2015, inclusive. We included hospitalizations from all provinces and territories except Quebec. Rates (per 100 000 persons) and relative proportions of hospitalizations by clinical condition, age group, sex and year are reported.

RESULTS

Between 2006 and 2015, the rate of cannabis-related hospitalizations in Canada doubled. Of special note, however, is that hospitalizations during this time period for those with the clinical condition code "mental and behavioural disorders due to use of cannabinoids, psychotic disorder" (F12.5) tripled, accounting for almost half (48%) of all cannabis-related hospitalizations in 2015.

CONCLUSION

Further research is required to investigate the reasons for the increase in hospitalizations for cannabis-related psychotic disorder. The introduction of high-potency cannabinoid products and synthetic cannabinoids into the illicit market are considered as possible factors.

Comparison of Water Pipes vs Other Modes of Cannabis Consumption and Subsequent Illicit Drug Use in a Longitudinal Cohort of Young Swiss Men

IMPORTANCE

There are concerns that the use of water pipes to consume cannabis is associated with increased risks of engaging in more addictive behaviors.

OBJECTIVE

To examine whether consuming cannabis with a water pipe was associated with later consumption of other illicit drugs compared with not using a water pipe.

DESIGN, SETTING, AND PARTICIPANTS

The Cohort Study on Substance Use Risk Factors (C-SURF) was a population-based study, recruiting 5987 Swiss men aged 18 to 25 years from 3 of 6 Swiss Armed Forces recruitment centers (response rate: 79.2%). The baseline assessment (t0) was done from 2010 to 2012, first follow-up (t1) from 2012 to 2014, and second follow-up (t2) from 2016 to 2018. Our sample included men who participated in both t0 and t2 assessments and used cannabis but no other illicit drugs at t0. Data analysis was performed from July 2020 to January 2021.

EXPOSURES

Cannabis use frequency and route of administration from self-administered questionnaires completed at t0 and t2.

MAIN OUTCOMES AND MEASURES

Outcome measures were initiation of illicit drug use and cannabis use disorder, identified by the Cannabis Use Disorder Identification Test. To examine whether water pipe use at t0 was associated with illicit drug use at t2, multivariable logistic regression analysis was performed.

RESULTS

Among 1108 Swiss male cannabis users who did not use other illicit drugs at t0, the mean (SD) age was 20 (1.2) years, 617 (55.7%) were from Switzerland's French-speaking region, and 343 (30%) used water pipes to consume cannabis. Water pipe users at t0 were more likely to use other illicit drugs at t2 compared with water pipe nonusers (adjusted odds ratio [aOR], 1.54; 95% CI, 1.10-2.16). The odds of using middle-stage drugs (including stimulants, hallucinogens, and inhaled drugs) at t2 were increased for water pipe users (aOR, 1.61; 95% CI, 1.13-2.29). Water pipe use at t0 was not associated with cannabis use disorder at t2 after adjusting for cannabis use frequency.

CONCLUSIONS AND RELEVANCE

This cohort study's results suggest that, among Swiss young men, water pipe use is associated with other illicit drug use later in life, particularly middle-stage illicit drugs. Preventive programs must focus on the potential of later harm to cannabis users who use water pipes but have not yet started taking other illicit drugs.

Cannabis use among military veterans: A great deal to gain or lose?

Policy changes have resulted in dramatic increases in access to cannabis for medical purposes. Veterans are disproportionately affected by conditions for which medical cannabis is often pursued, making an evidence-based perspective on risks versus benefits of high priority. The current review sought to examine the state of the evidence on the correlates and consequences of cannabis use among veterans. Using a comprehensive search strategy, 501 articles were identified and 86 studies met criteria for inclusion. The literature was predominated by cross-sectional studies (67%) of male veterans (71.4%-100% male) from the United States (93.0%). Three overarching themes emerged, comprising cannabis associations with other substance use, mental health, and physical health outcomes. The balance of the evidence associated cannabis use with negative health outcomes, with consistent positive associations with other substance use, psychiatric disorders, and self-harm/suicidality. Few studies examined the therapeutic effects of cannabis, thus limiting the potential to evaluate evidence of efficacy. Priority areas for future research are studies using designs that can examine the directionality of links between cannabis and health in veterans more conclusively, and studies directly examining therapeutic efficacy of cannabis-based therapies in veterans. Methodologically rigorous design will be essential to inform clinical recommendations and practices guidelines in an era of burgeoning access to cannabis.

Herbal Supplements: Can They Cause Hypomania?

Herbal medication use is prevalent and increasing in the general population. A comprehensive review of complementary and alternative medicine use including herbal medications and supplements is often overlooked by physicians. Patients generally believe that all herbal products are safe without any side-effects. Herbal medications may have complex pharmacodynamics and can be associated with various psychiatric symptoms. The general population, as well as physicians, may be unaware of the risks and side-effects associated with herbal supplement use and further research may be needed. The objective is to describe a case report of acute onset of symptoms of hypomania associated with the increasing use of herbal supplements. A 49-year-old man developed symptoms of hypomania after a two-month history of daily use of a combination of more than 25 herbal supplements and daily cannabis use. Hypomania symptoms were temporally associated with the use of multiple herbal supplements that included ginseng. We recommend that a thorough history of medication use including herbal supplements and other alternative medications and a collateral report from family members and other providers including herbalists be obtained on all patients presenting with psychiatric symptoms. Further research is needed to identify the pharmacodynamics, risks, and adverse effects, and drug and food interactions of each herb.

Cannabis Use and Prospective Long-Term Association with Anxiety: A Systematic Review and Meta-Analysis of Longitudinal Studies: Usage du cannabis et association prospective à long terme avec l'anxiété: une revue systématique et une méta-analyse d'études longitudinales

OBJECTIVES

Cannabis use is proposed as a risk factor for psychosis and is associated with depressive disorders. However, the relationship between recreational cannabis use and its longitudinal implications on anxiety conditions is less studied. The aim of this investigation is to systematically evaluate published literature and perform a meta-analysis of the data.

METHODS

A systematic search was performed of MEDLINE, Embase, and PsychINFO from inception to May 31, 2020, in addition to a hand search. Longitudinal studies that evaluated the relationship of cannabis use and development of anxiety were included. Where applicable, adjusted odds ratios (ORs) were extracted, pooled, and evaluated using random-effects meta-analysis.

RESULTS

After screening of unique abstracts (n = 6835), the final evaluation included 24 studies, of which 10 reported ORs that were analyzed quantitatively. Cannabis use was significantly associated with increased odds of developing any anxiety conditions (OR = 1.25; 95% CI, 1.01 to 1.54). Cannabis use was not significantly associated with developing generalized anxiety disorder, panic disorder, or social anxiety disorder. Review of studies not reporting OR revealed mixed results but are suggestive of a link between cannabis use and increased rates/severity of anxiety.

CONCLUSIONS

Published evidence suggests that cannabis use is likely associated with increased risk of anxiety in the long term but variability of study designs precludes declaration of a causal relationship. Awareness of this association is of relevance for both clinical practice and mental health policy implementation.

Cocaine and Marijuana Polysubstance Use and Cocaine Use Disorder: Investigating Mediated Effects through Patterns of Cocaine Use

Cocaine use is on the rise and it is comorbid with marijuana use. We examined the association between lifetime cocaine + marijuana polysubstance use (CM PSU) versus cocaine only and lifetime cocaine use disorder (CocUD) and examined the potential mediation by cocaine use patterns. Methods: A total of 2,968 lifetime cocaine users were identified from the National Epidemiologic Survey on Alcohol and Related Conditions-III. Mediation analysis was utilized to examine cocaine use quantity, frequency, and duration as potential mediators in the association between CM PSU and CocUD. A parallel multiple mediator model and a structural equation model were used, respectively, to examine: (1) the individual contribution of cocaine use quantity, frequency, and duration, and (2) combined contribution as a set specified by a latent variable. Results: Cocaine users were divided into 2,782 (93.7%) CM polysubstance users and 186 (6.3%) cocaine only users. CM PSU was associated with decreased risk of CocUD, but after including the mediators, the association was no longer significant. Examined separately, only quantity was found to be a significant mediator over and above frequency and duration, while the latent variable with three cocaine use pattern indicators explained 56.6% of the total association between CM PSU and CocUD. Conclusions: Compared to cocaine only users, CM polysubstance users were less likely to use cocaine heavily; this lower intensity of cocaine use was in turn associated with decreased risk of CocUD. Future research is warranted to determine the nature of the association between CM PSU and reduced CocUD.

Co-occurrence across time and space of drug- and cannabinoid- exposure and adverse mental health outcomes in the National Survey of Drug Use and Health: combined geotemporospatial and causal inference analysis

BACKGROUND

Whilst many studies have linked increased drug and cannabis exposure to adverse mental health (MH) outcomes their effects on whole populations and geotemporospatial relationships are not well understood.

METHODS

Ecological cohort study of National Survey of Drug Use and Health (NSDUH) geographically-linked substate-shapefiles 2010-2012 and 2014-2016 supplemented by five-year US American Community Survey. Drugs: cigarettes, alcohol abuse, last-month cannabis use and last-year cocaine use. MH: any mental illness, major depressive illness, serious mental illness and suicidal thinking.

DATA ANALYSIS

two-stage, geotemporospatial, robust generalized linear regression and causal inference methods in R.

RESULTS

410,138 NSDUH respondents. Average response rate 76.7%. When drug and sociodemographic variables were combined in geospatial models significant terms including tobacco, alcohol, cannabis exposure and various ethnicities remained in final models for all four major mental health outcomes. Interactive terms including cannabis were related to any mental illness (β-estimate = 1.97 (95%C.I. 1.56-2.37), P <  2.2 × 10^- 16), major depressive episode (β-estimate = 2.03 (1.54-2.52), P = 3.6 × 10^- 16), serious mental illness (SMI, β-estimate = 2.04 (1.48-2.60), P = 1.0 × 10^- 12), suicidal ideation (β-estimate = 1.99 (1.52-2.47), P <  2.2 × 10^- 16) and in each case cannabis alone was significantly associated (from β-estimate = - 3.43 (- 4.46 - -2.42), P = 3.4 × 10^- 11) with adverse MH outcomes on complex interactive regression surfaces. Geospatial modelling showed a monotonic upward trajectory of SMI which doubled (3.62 to 7.06%) as cannabis use increased. Extrapolated to whole populations cannabis decriminalization (4.26%, (4.18, 4.34%)), Prevalence Ratio (PR) = 1.035(1.034-1.036), attributable fraction in the exposed (AFE) = 3.28%(3.18-3.37%), P < 10^- 300) and legalization (4.75% (4.65, 4.84%), PR = 1.155 (1.153-1.158), AFE = 12.91% (12.72-13.10%), P < 10^- 300) were associated with increased SMI vs. illegal status (4.26, (4.18-4.33%)).

CONCLUSIONS

Data show all four indices of mental ill-health track cannabis exposure across space and time and are robust to multivariable adjustment for ethnicity, socioeconomics and other drug use. MH deteriorated with cannabis legalization. Cannabis use-MH data are consistent with causal relationships in the forward direction and include dose-response and temporal-sequential relationships. Together with similar international reports and numerous mechanistic studies preventative action to reduce cannabis use is indicated.

The Association Between Cannabis Use and Schizophrenia: Causative or Curative? A Systematic Review

Marijuana is one of the most abused substances in the world. Marijuana is getting legalized around the world. So, it is crucial to understand its effect on our mental health. Its impact on the schizophrenia spectrum needs our special attention. Even though marijuana has been around for a long time, its exact effects are still unknown. Schizophrenia is a chronic illness affecting approximately 20 million people worldwide. Schizophrenia and cannabis seem to have a close relationship, and we want to explore this. We want to know if marijuana is causing, exacerbating, or treating schizophrenia. This systematic review explores this question. We searched online resources like PubMed, PubMed Central, Cochrane Library, and Google Scholar for systematic reviews, traditional reviews, randomized controlled trials, and meta-analysis on cannabis and schizophrenia/ psychosis. We included human studies published in peer-reviewed journals in the English language in the last five years. After reviewing 96 initial results of our search, we excluded 25 duplicates, 29 abstracts, and 18 irrelevant articles. We did a quality assessment for the remaining 24 studies using various quality assessment tools. After the quality assessment, we found 12 articles were of low quality and excluded those. We included the remaining 12 final studies in our systematic review. Out of these 12 studies, five were traditional reviews, two systematic reviews, two meta-analysis, and three observational studies. Six of the articles were on cannabis’s effect on just schizophrenia or psychotic disorder. The other six included schizophrenia plus other psychiatric or neurological illnesses. Ten of the studies had data supporting the causative link between cannabis and schizophrenia. Eight records had data supporting the exacerbating effect of marijuana. Six studies had data supporting the therapeutic effect of the cannabidiol (CBD) component of cannabis. From the current data, we can conclude that the tetrahydrocannabinol (THC) component of cannabis can be the main culprit causing psychosis and schizophrenia in the at-risk population. THC can also be the one exacerbating symptoms and causing an adverse prognosis in already diagnosed patients. Even though CBD shows therapeutic effects and THC opposing effects, the data is minimal and low safety and efficacy warrants more research. The relation between cannabis and schizophrenia needs further investigation. We need more case-control studies and clinical trials with a larger population to get conclusive data.

Depressive symptoms moderate cannabis use for young adults in a Text-Delivered randomized clinical trial for cannabis use disorder

BACKGROUND

The importance and complexity of addressing both substance use and mood disorders such as depression within traditional treatment settings is well established. However, little is known about this issue within the context of mHealth treatment. Research is needed to determine if depression interacts with mHealth delivered cannabis use disorder treatment similarly compared traditional treatments.

OBJECTIVE

We examined the moderating effect of depressive symptoms on cannabis use with 96 young adults (ages 18 to 25) enrolled in a text-delivered randomized clinical trial for cannabis use disorder. Participants were followed for three months.

METHOD

We used a repeated measures general linear model to test if depressive symptoms moderated the treatment's effect on cannabis use. Self-report of past 30-day use and urinalysis of THC metabolites were the outcome measures. Depressive symptoms were measured using the PHQ-2, with scores >3 serving as the clinical cut-point, indicating likely depression disorder.

RESULTS

Participants with sub-threshold depression scores significantly reduced the number of days they used cannabis across all three months of the study. For participants with scores above the clinical cut-point, treatment had no effect on cannabis use. Similarly, participants with sub-threshold depression scores reduced the number of positive urinalysis results at three months. Effect sizes ranged from small to medium.

CONCLUSION

Results support the importance of simultaneously addressing depressive symptoms and cannabis use when treating young adults using text-delivered counseling. As mHealth interventions continue to demonstrate efficacy in addressing substance use disorders, the integration of mood disorder treatments appears warranted.

Marijuana Legalization and Youth

Various states have legalized marijuana for medical purposes and/or decriminalized recreational marijuana use. These changes coincide with a decrease in perceived harmfulness of the drug and an increase in its use among youth. This change is of critical concern because of the potential harmful impact of marijuana exposure on adolescents. Marijuana use has been associated with several adverse mental health outcomes, including increased incidence of addiction and comorbid substance use, suicidality, and new-onset psychosis. Negative impacts on cognition and academic performance have also been observed. As the trend toward legalization continues, the pediatric community will be called on to navigate the subsequent challenges that arise with changing policies. Pediatricians are uniquely positioned to provide innovative care and educate youth and families on the ever-evolving issues pertaining to the impact of marijuana legalization on communities. In this article, we present and analyze the most up-to-date data on the effects of legalization on adolescent marijuana use, the effects of adolescent use on mental health and cognitive outcomes, and the current interventions being recommended for use in pediatric office settings.

Prevalence of Cannabis Withdrawal Symptoms Among People With Regular or Dependent Use of Cannabinoids: A Systematic Review and Meta-analysis

IMPORTANCE

Cannabis withdrawal syndrome (CWS)-a diagnostic indicator of cannabis use disorder-commonly occurs on cessation of heavy and prolonged cannabis use. To date, the prevalence of CWS syndrome has not been well described, nor have the factors potentially associated with CWS.

OBJECTIVES

To estimate the prevalence of CWS among individuals with regular or dependent use of cannabinoids and identify factors associated with CWS.

DATA SOURCES

A search of literature from database inception to June 19, 2019, was performed using MEDLINE, Embase, PsycINFO, Web of Science, the Cumulative Index to Nursing and Allied Health Literature, ProQuest, Allied and Complementary Medicine, and Psychiatry online, supplemented by manual searches of reference lists of included articles.

STUDY SELECTION

Articles were included if they (1) were published in English, (2) reported on individuals with regular use of cannabinoids or cannabis use disorder as a primary study group, (3) reported on the prevalence of CWS or CWS symptoms using a validated instrument, (4) reported the prevalence of CWS, and (5) used an observational study design (eg, cohort or cross-sectional).

DATA EXTRACTION AND SYNTHESIS

All abstracts, full-text articles, and other sources were reviewed, with data extracted in duplicate. Cannabis withdrawal syndrome prevalence was estimated using a random-effects meta-analysis model, alongside stratification and meta-regression to characterize heterogeneity.

MAIN OUTCOMES AND MEASURES

Cannabis withdrawal syndrome prevalence was reported as a percentage with 95% CIs.

RESULTS

Of 3848 unique abstracts, 86 were selected for full-text review, and 47 studies, representing 23 518 participants, met all inclusion criteria. Of 23 518 participants included in the analysis, 16 839 were white (72%) and 14 387 were men (69%); median (SD) age was 29.9 (9.0) years. The overall pooled prevalence of CWS was 47% (6469 of 23 518) (95% CI, 41%-52%), with significant heterogeneity between estimates (I2 = 99.2%). When stratified by source, the prevalence of CWS was 17% (95% CI, 13%-21%) in population-based samples, 54% in outpatient samples (95% CI, 48%-59%), and 87% in inpatient samples (95% CI, 79%-94%), which were significantly different (P < .001). Concurrent cannabis (β = 0.005, P < .001), tobacco (β = 0.002, P = .02), and other substance use disorders (β = 0.003, P = .05) were associated with a higher CWS prevalence, as was daily cannabis use (β = 0.004, P < .001).

CONCLUSIONS AND RELEVANCE

These findings suggest that cannabis withdrawal syndrome appears to be prevalent among regular users of cannabis. Clinicians should be aware of the prevalence of CWS in order to counsel patients and support individuals who are reducing their use of cannabis.

Cannabis-based medicines for chronic pain management: current and future prospects

PURPOSE OF REVIEW

The medicinal use of cannabis has recently become the focus of much medical, as well as political, attention. This reality of growing use but limited evidence creates unique dilemmas for the prescribing clinician. The purpose of this review is to explore current evidence and gaps in knowledge and offer some practical considerations.

RECENT FINDINGS

There is robust preclinical data regarding the relevance of the endocannabinoid system to many pain-relevant processes. However, evidence to support cannabis-based medicines clinical use is still lacking. The best evidence to date is in managing neuropathic pain, although whether effects are clinically significant remains undetermined. However, the safety profile of cannabinoids seems favorable, especially by comparison to other medications used for pain control.

SUMMARY

The endocannabinoid system is undoubtedly a new and exciting pharmaceutical target for chronic pain management, but transition from preclinical to clinical studies has so far proved difficult. Although it is reasonable to consider cannabinoids for otherwise unresponsive pain, care should be taken in frail clinical populations. As this has become a socioeconomic and political issue in which agendas often take precedence over due diligence, there is a pressing need for unbiased empirical data and high quality evidence to better inform prescribers and patients.

Rates and correlates of risky firearm behaviors among adolescents and young adults treated in an urban emergency department

Firearm violence is a leading cause of death for urban adolescents and young adults (A/YAs). Little is known about patterns of risky firearm behaviors (RFBs) that may increase firearm-related fatality and non-fatal injury risk. To inform prevention efforts, we examined the rates and correlates of RFBs, including firearm carriage in risky situations (e.g., while drunk/high), discharge in risky situations (e.g., fleeing police), and firearm aggression (e.g., firearm threats/use against a partner/non-partner), among a sample of A/YAs (age-16-29) seeking medical or injury related care (7/2017-6/2018) at a Level-1 urban Emergency Department (ED). In total, 1312 A/YAs completed the survey (mean-age 23.2; 29.6%-male; 50.5%-Black; 56.3%-public assistance), with 102 (7.8%) engaging in RFBs. Among those engaging in RFBs, 42% reported firearm ownership, 68.6% firearm carriage in high-risk situations, 39.2% firearm discharge in risky situations, and 41.2% reported partner/non-partner firearm aggression. Regression identified RFBs correlates, including older age (AOR = 1.09), male sex (AOR = 1.63), Black race/ethnicity (AOR = 2.01), substance misuse (AOR = 2.75), attitudes favoring firearm use/retaliation (AOR = 1.38), peer firearm ownership/carriage (AOR = 3.26), higher levels of community violence exposure (AOR = 1.05), and active parole/probation (AOR 2.38). Higher coping skills were protective for RFBs (AOR = 0.83). Overall, we found that A/YAs seeking urban ED treatment reported elevated RFB rates, emphasizing the need for novel prevention initiatives, especially those incorporating tailored content addressing substance use, retaliatory violence, and peer delinquency/norms, while enhancing self-efficacy for avoiding RFBs and providing access to external resources within a resiliency-based framework. Such prevention approaches may be a critical step towards addressing the public health problem of firearm violence. Primary Funding Sources: NIH/NIDA K23DA039341; NIH/NCATS UL1TR000433.

Cannabis Use and the Risk for Psychosis and Affective Disorders

Objective: This review discusses the relationship between cannabis use and psychotic, bipolar, depressive, and anxiety disorders, as well as suicide. It summarizes epidemiological evidence from cross-sectional and long-term prospective studies and considers possible etiological mechanisms. Methods: Systematic reviews and methodologically robust studies in the field (from inception to February 2019) were identified using a comprehensive search of Medline, PsychINFO, and Embase and summarized using a narrative synthesis. Results: Consistent evidence, both from observational and experimental studies, has confirmed the important role of cannabis use in the initiation and persistence of psychotic disorders. The size of the effect is related to the extent of cannabis use, with greater risk for early cannabis use and use of high-potency varieties and synthetic cannabinoids. Accumulating evidence suggests that frequent cannabis use also increases the risk for mania as well as for suicide. However, the effect on depression is less clear and findings on anxiety are contradictory with only a few methodologically robust studies. Furthermore, the relationship with common mental disorders may involve reverse causality, as depression and anxiety are reported to lead to greater cannabis consumption in some studies. Pathogenetic mechanisms focus on the effect of tetrahydrocannabinol (THC, the main psychoactive ingredient of cannabis) interacting with genetic predisposition and perhaps other environmental risk factors. Cannabidiol (CBD), the other important ingredient of traditional cannabis, ameliorates the psychotogenic effects of THC but is absent from the high-potency varieties that are increasingly available. Conclusions: The evidence that heavy use of high-THC/low-CBD types of cannabis increases the risk of psychosis is sufficiently strong to merit public health education. Evidence of similar but smaller effects in mania and suicide is growing, but is not convincing for depression and anxiety. There is much current interest in the possibility that CBD may be therapeutically useful.

Polysubstance Use by Stimulant Users: Health Outcomes Over Three Years

OBJECTIVE

Studies show that stimulant users have varied substance use patterns and that polysubstance use is associated with poorer past or concurrent medical, mental health, and substance use outcomes. This study examined outcomes of substance use patterns prospectively.

METHOD

A latent class analysis was conducted to examine substance use patterns among adults using stimulants (n = 710; 38.6% women) at baseline, and the health and treatment utilization outcomes of different use patterns over the subsequent 3 years. To examine associations between latent class membership and outcomes, generalized estimating equation modeling was conducted.

RESULTS

Four classes of substance use patterns at baseline were identified, involving high use of (a) methamphetamine and marijuana (23%); (b) crack cocaine and alcohol (25%); (c) powder cocaine, alcohol, and marijuana (23%); and (d) nonprescribed opioids, alcohol, marijuana, crack cocaine, and powder cocaine (i.e., polysubstance [29%]). Polysubstance class members had poorer physical health and mental health status, and more severe substance use, over the subsequent 3-year period, than other class members. Regarding treatment utilization, polysubstance class members had more medical care utilization than crack cocaine class members, and more substance use treatment utilization than powder cocaine class members. The methamphetamine, crack cocaine, and powder cocaine classes did not differ from each other on any health or treatment utilization outcome.

CONCLUSIONS

People using stimulants commonly use other substances, and those whose polysubstance use includes nonprescribed opioids have especially poor health outcomes.

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.

Age-varying effects of cannabis use frequency and disorder on symptoms of psychosis, depression and anxiety in adolescents and adults

AIMS

We tested the age-varying associations of cannabis use (CU) frequency and disorder (CUD) with psychotic, depressive and anxiety symptoms in adolescent and adult samples. Moderating effects of early onset (≤ 15 years) and sex were tested.

DESIGN

Time-varying effect models were used to assess the significance of concurrent associations between CU and CUD and symptoms of psychosis, depression and anxiety at each age.

SETTING AND PARTICIPANTS

Adolescent data (V-HYS; n = 662) were collected from a randomly recruited sample of adolescents in Victoria, British Columbia, Canada during a 10-year period (2003-13). Adult cross-sectional data (NESARC-III; n = 36 309) were collected from a representative sample from the United States (2012-13).

MEASUREMENTS

Mental health symptoms were assessed using self-report measures of diagnostic symptoms. CU was based on frequency of past-year use. Past-year CUD was based on DSM-5 criteria.

FINDINGS

For youth in the V-HYS, CU was associated with psychotic symptoms following age 22 [b = 0.13, 95% confidence interval (CI) = 0.002, 0.25], with depressive symptoms from ages 16-19 and following age 25 (b = 0.17, 95% CI = 0.003, 0.34), but not with anxiety symptoms. CUD was associated with psychotic symptoms following age 23 (b = 0.51, 95% CI = 0.01, 1.01), depressive symptoms at ages 19-20 and following age 25 (b = 0.71, 95% CI = 0.001, 1.42) and anxiety symptoms ages 26-27 only. For adults in the NESARC-III, CU was associated with mental health symptoms at most ages [e.g. psychotic symptoms; age 18 (b = 0.22, 95% CI = 0.10, 0.33) to age 65 (b = 0.36, 95% CI = 0.16, 0.56)]. CUD was associated with all mental health symptoms across most ages [e.g. depressive symptoms; age 18 (b = 0.96, 95% CI = 0.19, 1.73) to age 61 (b = 1.11, 95% CI = 0.01, 2.21)]. Interactions with sex show stronger associations for females than males in young adulthood [e.g.

V-HYS

CUD × sex interaction on psychotic symptoms significant after age 26 (b = 1.12, 95% CI = 0.02, 2.21)]. Findings were not moderated by early-onset CU.

CONCLUSIONS

Significant associations between cannabis use (CU) frequency and disorder (CUD) and psychotic and depressive symptoms in late adolescence and young adulthood extend across adulthood, and include anxiety.

Trends in cannabis use over time among Canadian youth: 2004-2014

Cannabis is the most commonly used illicit substance among Canadian youth. The current study examined national trends in cannabis use among Canadian youth from 2004/05 to 2014/15 using nationally representative data from the Canadian Student Tobacco, Alcohol and Drugs Survey (CSTADS). Data were collected from students in Grades 7 to 12 as part of the Canadian Student Tobacco, Alcohol and Drugs Survey (formerly the Youth Smoking Survey) using a repeat-cross sectional survey across 6 biennial survey waves between 2004 and 2014 (N = 243,057). Regression models examined factors associated with cannabis use in the past 12 months, perceived ease of access, and a multilinear regression examined age of initiation across survey cycles. The findings indicate that use of cannabis in the past 12-months significantly decreased among Canadian youth. Past-year use peaked in 2008/09 at 27.3%; compared to 16.5%, in 2014/15. Mean age of initiation did not vary over time, while youth in recent cycles reported that cannabis was more difficult to access: in 2006/07, 77.1% reported that it would be easy to access cannabis compared to 49.0% in 2014/15. Overall, cannabis use among Canadian youth appears to have peaked around 2008/09, with substantial declines over the past decade. It will be critically important to examine any changes in patterns of use following legalization of non-medical cannabis in Canada.

Polysubstance Use by Stimulant Users: Health Outcomes Over Three Years

OBJECTIVE

Studies show that stimulant users have varied substance use patterns and that polysubstance use is associated with poorer past or concurrent medical, mental health, and substance use outcomes. This study examined outcomes of substance use patterns prospectively.

METHOD

A latent class analysis was conducted to examine substance use patterns among adults using stimulants (n = 710; 38.6% women) at baseline, and the health and treatment utilization outcomes of different use patterns over the subsequent 3 years. To examine associations between latent class membership and outcomes, generalized estimating equation modeling was conducted.

RESULTS

Four classes of substance use patterns at baseline were identified, involving high use of (a) methamphetamine and marijuana (23%); (b) crack cocaine and alcohol (25%); (c) powder cocaine, alcohol, and marijuana (23%); and (d) nonprescribed opioids, alcohol, marijuana, crack cocaine, and powder cocaine (i.e., polysubstance [29%]). Polysubstance class members had poorer physical health and mental health status, and more severe substance use, over the subsequent 3-year period, than other class members. Regarding treatment utilization, polysubstance class members had more medical care utilization than crack cocaine class members, and more substance use treatment utilization than powder cocaine class members. The methamphetamine, crack cocaine, and powder cocaine classes did not differ from each other on any health or treatment utilization outcome.

CONCLUSIONS

People using stimulants commonly use other substances, and those whose polysubstance use includes nonprescribed opioids have especially poor health outcomes.

"Hallucinations" Following Acute Cannabis Dosing: A Case Report and Comparison to Other Hallucinogenic Drugs

Introduction: Cannabis has been historically classified as a hallucinogen. However, subjective cannabis effects do not typically include hallucinogen-like effects. Empirical reports of hallucinogen-like effects produced by cannabis in controlled settings, particularly among healthy research volunteers, are rare and have mostly occurred after administration of purified Δ-9 tetrahydrocannabinol (THC) rather than whole plant cannabis.

Methods: The case of a healthy 30-year-old male who experienced auditory and visual hallucinations in a controlled laboratory study after inhaling vaporized cannabis that contained 25 mg THC (case dose) is presented. Ratings on the Hallucinogen Rating Scale (HRS) following the case dose are compared with HRS ratings obtained from the participant after other doses of cannabis and with archival HRS data from laboratory studies involving acute doses of cannabis, psilocybin, dextromethorphan (DXM), and salvinorin A.

Results: Scores on the Volition subscale of the HRS were greater for the case dose than for the maximum dose administered in any other comparison study. Scores on the Intensity and Perception subscales were greater for the case dose than for the maximum dose of cannabis, psilocybin, or salvinorin A. Scores on the Somaesthesia subscale were greater for the case dose than for the maximum dose of DXM, salvinorin A, or cannabis. Scores on the Affect and Cognition subscales for the case dose were significantly lower than for the maximum doses of psilocybin and DXM.

Conclusion: Acute cannabis exposure in a healthy adult male resulted in self-reported hallucinations that rated high in magnitude on several subscales of the HRS. However, the hallucinatory experience in this case was qualitatively different than that typically experienced by participants receiving classic and atypical hallucinogens, suggesting that the hallucinatory effects of cannabis may have a unique pharmacological mechanism of action. This type of adverse event needs to be considered in the clinical use of cannabis.

Marijuana and acute health care contacts in Colorado

Over 22 million Americans are current users of marijuana; half of US states allow medical marijuana, and several allow recreational marijuana. The objective of this study was to evaluate the impact marijuana has on hospitalizations, emergency department (ED) visits, and regional poison center (RPC) calls in Colorado, a medical and recreational marijuana state. This is a retrospective review using Colorado Hospital Association hospitalizations and ED visits with marijuana-related billing codes, and RPC marijuana exposure calls. Legalization of marijuana in Colorado has been associated with an increase in hospitalizations, ED visits, and RPC calls linked with marijuana exposure. From 2000 to 2015, hospitalization rates with marijuana-related billing codes increased from 274 to 593 per 100,000 hospitalizations in 2015. Overall, the prevalence of mental illness among ED visits with marijuana-related codes was five-fold higher (5.07, 95% CI: 5.0, 5.1) than the prevalence of mental illness without marijuana-related codes. RPC calls remained constant from 2000 through 2009. However, in 2010, after local medical marijuana policy liberalization, the number of marijuana exposure calls significantly increased from 42 to 93; in 2014, after recreational legalization, calls significantly increased by 79.7%, from 123 to 221 (p<0.0001). The age group <17years old also had an increase in calls after 2014. As more states legalize marijuana, it is important to address public education and youth prevention, and understand the impact on mental health disorders. Improvements in data collection and surveillance methods are needed to more accurately evaluate the public health impact of marijuana legalization.

Polysubstance use by psychiatry inpatients with co-occurring mental health and substance use disorders

BACKGROUND

Polysubstance use, the consumption of more than one substance over a defined period, is common and associated with psychiatric problems and poor treatment adherence and outcomes. This study examined past-month polysubstance use at intake among psychiatry inpatients with co-occurring mental health and substance use disorders, and outcomes 3 months later.

METHODS

Participants (n=406 psychiatry inpatients with documented mental health and substance use disorders) completed a baseline and a 3-month follow-up (84%) interview. With baseline data, a latent class analysis was conducted on substances used in the past 30days. Analyses of covariance tested for differences among classes on outcomes at 3-month follow-up.

RESULTS

At baseline, three classes were estimated: Cannabis+Alcohol (35.1%), Alcohol (49.3%), and Polysubstance, notably, cocaine plus alcohol and marijuana (15.7%). At follow-up, the Polysubstance class had more severe alcohol and drug use, support for abstinence, and motivation for help-seeking, but less abstinence self-efficacy; it was most likely to attend 12-step groups. The Cannabis+Alcohol class was least likely to obtain outpatient substance use treatment, and had the lowest percent days abstinent.

CONCLUSIONS

Psychiatry inpatients with co-occurring substance use and mental health disorders have varying substance use patterns that correspond to substance-related outcomes concurrently and over time. Many patients achieved abstinence for most days of the 3-month post-hospitalization period. To further increase abstinence, providers could build on polysubstance-using patients' high motivation to increase self-efficacy. In addition, because patients using mainly cannabis plus alcohol may perceive little harm from cannabis use, providers may consider modifying risk perceptions through effective education.

Reductions in cannabis use are associated with improvements in anxiety, depression, and sleep quality, but not quality of life

AIMS

This study examined the longitudinal association between reductions in cannabis use and changes in anxiety, depression, sleep quality, and quality of life.

METHODS

Secondary analyses were conducted based on data from a cannabis use disorder medication trial in 302 adults (ages 18-50). Changes in symptoms of anxiety and depression, sleep quality, and quality of life were assessed in relation to changes in cannabis use during the 12-week trial of treatment.

RESULTS

Based on the slope of individual cannabis use trajectory, the sample was classified into two groups (Cannabis Use Reduction, n=152 vs. Cannabis Use Increase, n=150) which was included as a binary covariate in subsequent modeling. Controlling for demographics (age, gender, race/ethnicity), treatment condition, and time-varying tobacco and alcohol use, separate latent growth curve models showed a significant association between the Cannabis Use Reduction group and improvement (i.e., lower values in slope) in anxiety (β=-0.09, SE=0.04; p<0.05), depression (β=-0.11, SE=0.04; p<0.01), and sleep quality (β=-0.07, SE=0.03; p<0.05) over the observation period, but not in quality of life.

CONCLUSIONS

These results indicate a longitudinal relationship between reductions in cannabis use and improvements in anxiety, depression, and sleep quality. Clinicians treating patients with co-occurring cannabis use and problems with anxiety, depression, or sleep quality should attend to cannabis use reduction as a component of treatment.