Adolescent Initiation of Cannabis Use and Early-Onset Psychosis

Disentangling heterogeneity in substance use disorder: Insights from genome-wide polygenic scores

Substance use disorder (SUD) is a global health problem with a significant impact on individuals and society. The presentation of SUD is diverse, involving various substances, ages at onset, comorbid conditions, and disease trajectories. Current treatments for SUD struggle to address this heterogeneity, resulting in high relapse rates. SUD often co-occurs with other psychiatric and mental health-related conditions that contribute to the heterogeneity of the disorder and predispose to adverse disease trajectories. Family and genetic studies highlight the role of genetic and environmental factors in the course of SUD, and point to a shared genetic liability between SUDs and comorbid psychopathology. In this study, we aimed to disentangle SUD heterogeneity using a deeply phenotyped SUD cohort and polygenic scores (PGSs) for psychiatric disorders and related traits. We explored associations between PGSs and various SUD-related phenotypes, as well as PGS-environment interactions using information on lifetime emotional, physical, and/or sexual abuse. Our results identify clusters of individuals who exhibit differences in their phenotypic profile and reveal different patterns of associations between SUD-related phenotypes and the genetic liability for mental health-related traits, which may help explain part of the heterogeneity observed in SUD. In our SUD sample, we found associations linking the genetic liability for attention-deficit hyperactivity disorder (ADHD) with lower educational attainment, the genetic liability for post-traumatic stress disorder (PTSD) with higher rates of unemployment, the genetic liability for educational attainment with lower rates of criminal records and unemployment, and the genetic liability for well-being with lower rates of outpatient treatments and fewer problems related to family and social relationships. We also found evidence of PGS-environment interactions showing that genetic liability for suicide attempts worsened the psychiatric status in SUD individuals with a history of emotional physical and/or sexual abuse. Collectively, these data contribute to a better understanding of the role of genetic liability for mental health-related conditions and adverse life experiences in SUD heterogeneity.

Illness-related outcomes of illicit substance use disorder in adolescents with early onset schizophrenia: a multicenter study

OBJECTIVES

Lifetime co-occurring substance use disorders are common at the time of presentation for the treatment of primary psychosis. Our aim was to investigate the clinical characteristics of adolescents with early-onset schizophrenia/schizoaffective disorder (EOS), categorized as either with (EOS + SUD) or without SUD (non-SUD/EOS), in a multi-center sample.

METHODS

Between 2016 and 2022, 255 patients were evaluated across three tertiary-care inpatient units. Diagnoses were confirmed by the treating physician according to the DSM-5 during the hospital stay. The severity of symptoms was measured using the Positive and Negative Syndrome Scale (PANSS).

RESULTS

The EOS + SUD group exhibited a higher illness onset, fewer years of education, longer duration of untreated psychosis (DUP), a higher frequency of male gender, more frequent hospitalizations, increased use of clozapine and zuclopenthixol LAI, along with higher rates of post-traumatic stress disorder and conduct disorder. Notably, differences in DUP, clozapine use, and the number of hospitalizations did not persist in the multivariate logistic regression model.

CONCLUSIONS

Our findings support the notion of SUD playing a role in modifying the course of illness in EOS. Future studies should emphasize exploring treatment responses to medications and interventions among youth with dual diagnoses.

Neuroanatomical variability associated with early substance use initiation: Results from the ABCD Study

The extent to which neuroanatomical variability associated with substance involvement reflects pre-existing risk and/or consequences of substance exposure remains poorly understood. In the Adolescent Brain Cognitive DevelopmentSM (ABCD®) Study, we identify associations between global and regional differences in brain structure and early substance use initiation (i.e., occurring <15 years of age; nsanalytic=6,556-9,804), with evidence that associations precede initiation. Neurodevelopmental variability in brain structure may confer risk for substance involvement.

The impact of recreational cannabis legalization on youth: the Colorado experience

Over the past two decades, cannabis policies have liberalized in the United States, culminating in the legalization of recreational cannabis in Colorado and Washington state in 2012. This review will focus on the impact of recreational cannabis legalization in Colorado. While the prevalence of past-year and past-month cannabis use has remained relatively steady among adolescents post-legalization, the prevalence of young adult use has continued to rise. Cannabis products with increased potency have become more prevalent and widely used. There are concerns that the use of products with increased potency will increase risk for cannabis use and comorbid mental health disorders, particularly cannabis-induced psychosis and suicidal behavior, although more research is needed to fully understand the impact of high-potency products. Since the legalization of recreational cannabis, numerous additional public health concerns have emerged: unintentional overdoses requiring acute care visits, electronic vaping-associated lung injury, increased motor vehicle collisions related to cannabis consumption, and higher rates of cannabis use during pregnancy. Lessons learned from the first decade of cannabis legalization emphasize the need for research efforts to provide evidence-based guidelines, inform prevention strategies, and implement selective interventions for at-risk populations including youth, individuals with comorbid mental health disorders, and individuals who are pregnant.

Is There a Dose-Response Relationship Between Cannabis Use and Violence? A Longitudinal Study in Individuals with Severe Mental Disorders

Introduction: Recent longitudinal studies point toward the existence of a positive relationship between cannabis use and violence in people with severe mental disorders (SMD). However, the existence of a dose-response relationship between the frequency/severity of cannabis use and violence has seldom been investigated. Therefore, this study aims to determine if such a relationship exists in a psychiatric population. Methods: To do so, a total of 98 outpatients (81 males and 17 females, all over 18 years of age) with SMD were recruited at the Institut universitaire de santé mentale de Montréal (Montréal, Canada) and included in the analyses. Clinical evaluations were conducted every 3 months for a year. Substance use, violent behaviors, and potential covariables were assessed through self-reported assessments, urinary testing, as well as clinical, criminal, and police records. Using generalized estimating equations, the association between cannabis use frequency (nonusers, occasional, regular, and frequent users) and violence was investigated, as well as the association between the severity of cannabis use and violent behaviors. Results: It was found that cannabis use frequency and severity were significant predictors of violent behaviors. After adjustment for time, age, sex, ethnicity, diagnoses, impulsivity, and use of alcohol and stimulants, odds ratios were of 1.91 (p<0.001) between each frequency profile and 1.040 (p<0.001) for each increase of one point of the severity of cannabis use score (ranging from 0 to 79). Conclusions: Despite the high attrition rate, these findings may have important implications for clinicians as cannabis use may have serious consequences in psychiatric populations. Nevertheless, the mechanisms underlying this association remain unclear.

Neural correlates of negative life events and their relationships with alcohol and cannabis use initiation

OBJECTIVE

Negative life events (NLEs), e.g., poor academic performance (controllable) or being the victim of a crime (uncontrollable), can profoundly affect the trajectory of one's life. Yet, their impact on how the brain develops is still not well understood. This investigation examined the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) dataset for the impact of NLEs on the initiation of alcohol and cannabis use, as well as underlying neural mechanisms.

METHODS

This study evaluated the impact of controllable and uncontrollable NLEs on substance use initiation in 207 youth who initiated alcohol use, 168 who initiated cannabis use, and compared it to 128 youth who remained substance-naïve, using generalised linear regression models. Mediation analyses were conducted to determine neural pathways of NLE impacting substance use trajectories.

RESULTS

Dose-response relationships between controllable NLEs and substance use initiation were observed. Having one controllable NLE increased the odds of alcohol initiation by 50% (95%CI [1.18, 1.93]) and cannabis initiation by 73% (95%CI [1.36, 2.24]), respectively. Greater cortical thickness in left banks of the superior temporal sulcus mediated effects of controllable NLEs on alcohol and cannabis initiations. Greater left caudate gray-matter volumes mediated effects of controllable NLEs on cannabis initiation.

CONCLUSIONS

Controllable but not uncontrollable NLEs increased the odds of alcohol and cannabis initiation. Moreover, those individuals with less mature brain structures at the time of the NLEs experienced a greater impact of NLEs on subsequent initiation of alcohol or cannabis use. Targeting youth experiencing controllable NLEs may help mitigate alcohol and cannabis initiation.

Cannabis and Psychosis

Psychosis and cannabis use may overlap in multiple ways in young people. Research suggests that cannabis use increases risk for having psychotic symptoms, both attenuated (subthreshold) and acute. Cannabis use may also exacerbate psychosis symptoms among young people with underlying psychosis risk and psychotic disorders. Although there are suggestions for treating co-occurring psychosis and cannabis use in young people (e.g., incorporating cannabis use assessment and treatment strategies into specialized early psychosis care), there are many gaps in clinical trial research to support evidence-based treatment of these overlapping concerns.

Association between Cannabis Use Disorder and Mental Health Disorders in the Adolescent Population: A Cohort Study

INTRODUCTION

According to the literature, early initiation to cannabis use and a dependent pattern of use are important risk factors for the development of mental health disorders. However, there are few cohort studies which look at the development of mental health disorders associated with cannabis use among young people with cannabis use disorder (CUD). The aim of the study was to determine the cumulative incidence of mental health disorders and the risk of developing mental health disorders among minors who commenced treatment for CUD in Catalonia during 2015-2019.

METHODS

This was a retrospective fixed cohort study, matched for confounding variables, based on data from the Catalan Health Surveillance System. The exposed cohort comprised young people who entered treatment for CUD during 2015-2019 (n = 948) and who were minors on the date of commencing treatment. Matching was done with a paired cohort (n = 4,737), according to confounding variables. Individuals with a diagnosis of a mental health disorder prior to the study period were excluded. The cumulative incidence was calculated for mental health disorders for the exposed and the paired cohorts and stratified by type of mental disorder. Incidence rate ratios were estimated using the conditional Poisson model with robust variance, stratified by sex.

RESULTS

The cumulative incidence for development of a mental health disorder was 19.6% in the exposed cohort and 3.1% in the paired cohort; with higher incidence among females (females 32.7%; males 15.8%). The exposed cohort had an 8.7 times increased risk of developing a mental health disorder than the paired cohort. The most frequent diagnoses were reaction to severe stress, adjustment disorder, and personality disorders.

CONCLUSION

This study confirmed that the exposed cohort was at increased risk of developing mental health disorders compared to the paired cohort. To date, few studies have analyzed the association between cannabis use and the development of mental health disorders, considering cannabis dependence. Further studies should be undertaken considering CUD. In addition, more studies are needed to understand the factors that determine the development of CUD. Further research in these areas would contribute to the design of prevention strategies aimed at those young individuals with a higher risk of developing cannabis dependence and suffering its consequences.

Review of Major Social Determinants of Health in Schizophrenia-Spectrum Psychotic Disorders: III. Biology

BACKGROUND

Social determinants of health (SDoHs) are nonmedical factors that significantly impact health and longevity. We found no published reviews on the biology of SDoHs in schizophrenia-spectrum psychotic disorders (SSPD).

STUDY DESIGN

We present an overview of pathophysiological mechanisms and neurobiological processes plausibly involved in the effects of major SDoHs on clinical outcomes in SSPD.

STUDY RESULTS

This review of the biology of SDoHs focuses on early-life adversities, poverty, social disconnection, discrimination including racism, migration, disadvantaged neighborhoods, and food insecurity. These factors interact with psychological and biological factors to increase the risk and worsen the course and prognosis of schizophrenia. Published studies on the topic are limited by cross-sectional design, variable clinical and biomarker assessments, heterogeneous methods, and a lack of control for confounding variables. Drawing on preclinical and clinical studies, we propose a biological framework to consider the likely pathogenesis. Putative systemic pathophysiological processes include epigenetics, allostatic load, accelerated aging with inflammation (inflammaging), and the microbiome. These processes affect neural structures, brain function, neurochemistry, and neuroplasticity, impacting the development of psychosis, quality of life, cognitive impairment, physical comorbidities, and premature mortality. Our model provides a framework for research that could lead to developing specific strategies for prevention and treatment of the risk factors and biological processes, thereby improving the quality of life and increasing the longevity of people with SSPD.

CONCLUSIONS

Biology of SDoHs in SSPD is an exciting area of research that points to innovative multidisciplinary team science for improving the course and prognosis of these serious psychiatric disorders.

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.

THC and CBD: Villain versus Hero? Insights into Adolescent Exposure

Cannabis is the most used drug of abuse worldwide. It is well established that the most abundant phytocannabinoids in this plant are Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD). These two compounds have remarkably similar chemical structures yet vastly different effects in the brain. By binding to the same receptors, THC is psychoactive, while CBD has anxiolytic and antipsychotic properties. Lately, a variety of hemp-based products, including CBD and THC, have become widely available in the food and health industry, and medical and recreational use of cannabis has been legalized in many states/countries. As a result, people, including youths, are consuming CBD because it is considered “safe”. An extensive literature exists evaluating the harmful effects of THC in both adults and adolescents, but little is known about the long-term effects of CBD exposure, especially in adolescence. The aim of this review is to collect preclinical and clinical evidence about the effects of cannabidiol.

Cannabis in Adolescence: Lasting Cognitive Alterations and Underlying Mechanisms

Cannabis consumption during adolescence is an area of particular concern, owing to changes in the social and political perception of the drug, and presents a scientific, medical, and economic challenge. Major social and economic interests continue to push toward cannabis legalization as well as pharmaceutical development. As a result, shifting perceptions of both legal and illicit cannabis use across the population have changed the collective evaluation of the potential dangers of the product. The wave of cannabis legalization therefore comes with new responsibility to educate the public on potential risks and known dangers associated with both recreational and medical cannabis. Among these is the risk of long-term cognitive and psychological consequences, particularly following early-life initiation of use, compounded by high-potency and/or synthetic cannabis, and heavy/frequent use of the drug. Underlying these cognitive and psychiatric consequences are lasting aberrations in the development of synaptic function, often secondary to epigenetic changes. Additional factors such as genetic risk and environmental influences or nondrug toxic insults during development are also profound contributors to these long-term functional alterations following adolescent cannabis use. Preclinical studies indicate that exposure to cannabinoids during specific windows of vulnerability (e.g., adolescence) impacts neurodevelopmental processes and behavior by durably changing dendritic structure and synaptic functions, including those normally mediated by endogenous cannabinoids and neuronal circuits.

Cannabis and Psychosis

Psychosis and cannabis use may overlap in multiple ways in young people. Research suggests that cannabis use increases risk for having psychotic symptoms, both attenuated (subthreshold) and acute. Cannabis use may also exacerbate psychosis symptoms among young people with underlying psychosis risk and psychotic disorders. Although there are suggestions for treating co-occurring psychosis and cannabis use in young people (e.g., incorporating cannabis use assessment and treatment strategies into specialized early psychosis care), there are many gaps in clinical trial research to support evidence-based treatment of these overlapping concerns.

Substance use and psychotic-like experiences in young people: a systematic review and meta-analysis

This study aimed to systematically review and synthesise the available evidence on the prevalence and associations between psychotic-like experiences (PLEs) and substance use in children and adolescents aged ⩽17 years, prior to the typical age of development of prodromal symptoms of psychosis. As substance use has been associated with earlier age of psychosis onset and more severe illness, identifying risk processes in the premorbid phase of the illness may offer opportunities to prevent the development of prodromal symptoms and psychotic illness. MEDLINE, PsycINFO, and CINAHL databases were searched for chart review, case-control, cohort, twin, and cross-sectional studies. Study reporting was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist, and pooled evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Searches identified 55 studies that met inclusion criteria. Around two-in-five substance users reported PLEs [rate = 0.41, 95% confidence interval (CI) 0.32-0.51; low quality evidence], and one-in-five with PLEs reported using substances (rate = 0.19, 95% CI 0.12-0.28; moderate-to-high quality evidence). Substance users were nearly twice as likely to report PLEs than non-users [odds ratio (OR) 1.77, 95% CI 1.55-2.02; moderate quality evidence], and those with PLEs were twice as likely to use substances than those not reporting PLEs (OR 1.93, 95% CI 1.55-2.41; very low quality evidence). Younger age was associated with greater odds of PLEs in substance users compared to non-users. Young substance users may represent a subclinical at-risk group for psychosis. Developing early detection and intervention for both substance use and PLEs may reduce long-term adverse outcomes.

Cannabidiol for the treatment of autism spectrum disorder: hope or hype?

RATIONALE

Autism spectrum disorder (ASD) is defined as a group of neurodevelopmental disorders whose symptoms include impaired communication and social interaction, restricted and repetitive patterns of behavior, and varying levels of intellectual disability. ASD is observed in early childhood and is one of the most severe chronic childhood disorders in prevalence, morbidity, and impact on society. It is usually accompanied by attention deficit hyperactivity disorder, anxiety, depression, sleep disorders, and epilepsy. The treatment of ASD has low efficacy, possibly because it has a heterogeneous nature, and its neurobiological basis is not clearly understood. Drugs such as risperidone and aripiprazole are the only two drugs available that are recognized by the Food and Drug Administration, primarily for treating the behavioral symptoms of this disorder. These drugs have limited efficacy and a high potential for inducing undesirable effects, compromising treatment adherence. Therefore, there is great interest in exploring the endocannabinoid system, which modulates the activity of other neurotransmitters, has actions in social behavior and seems to be altered in patients with ASD. Thus, cannabidiol (CBD) emerges as a possible strategy for treating ASD symptoms since it has relevant pharmacological actions on the endocannabinoid system and shows promising results in studies related to disorders in the central nervous system.

OBJECTIVES

Review the preclinical and clinical data supporting CBD's potential as a treatment for the symptoms and comorbidities associated with ASD, as well as discuss and provide information with the purpose of not trivializing the use of this drug.

Cannabis Use in Autism: Reasons for Concern about Risk for Psychosis

Being particularly vulnerable to the pro-psychotic effects of cannabinoid exposure, autism spectrum individuals present with an increased risk of psychosis, which may be passed on to their own children. More specifically, cannabis exposure among autism spectrum individuals seems to exert disruptive epigenetic effects that can be intergenerationally inherited in brain areas which play a critical role in schizophrenia pathophysiology. Additionally, because of such cannabinoid-induced epigenetic effects, autism candidate genes present with bivalent chromatin markings which make them more vulnerable to subsequent disruption, possibly leading to psychosis onset later in life. Thus, findings support a developmental trajectory between autism and psychosis, as per endocannabinoid system modulation. However, such evidence has not received the attention it deserves.

The Potential Paradoxical Neurocognitive Effects of Cannabis Use in Patients with Psychotic Disorders: A Critical Meta-Review of Meta-Analytical Evidence

Background: The association between cannabis and cognitive functions has been thoroughly studied in psychotic disorders, but conflictual/paradoxical results have emerged. This critical meta-review examined the magnitude of effects of cannabis on neurocognitive functions in patients with psychotic disorders provided by meta-analyses and evaluated the quality of evidence. Methods: A systematic search of meta-analyses was performed in PubMed, PsycINFO, Web of Science, and Google Scholar. Results: The search retrieved six meta-analyses. Quality of evidence varied from very low to moderate quality. No neurocognitive difference was observed between cannabis users and nonusers in first episode of psychosis samples. Limited evidence showed no significant difference in language, psychomotor functioning, and verbal/visual learning/memory, apart from improvements in verbal and visual memory (recognition). Findings showed better neurocognitive performances in cannabis-using patients for planning/reasoning and working memory. There were tendencies toward significance for processing speed and attention. Most effect sizes showed small to moderate degrees of outperformances in cannabis users. Individuals with lifetime use appeared to show better neurocognitive functions. Conclusion: Evidence indicated nonuniform effects of cannabis use across cognitive domains, with some areas suggesting better cognitive performances in cannabis users, entitled the paradoxical effect of the dually diagnosed. Clinical significance of these findings should be interpreted cautiously.

Effect modification of legalizing recreational cannabis use on the association between e-cigarette use and future cannabis use among US adolescents

BACKGROUND

Many states have legalized recreational cannabis use for adults. However, no study has examined how this policy may interact with youth vaping to influence cannabis use among US adolescents. This study investigates whether the association between baseline e-cigarette use and subsequent cannabis use differs by state recreational cannabis legalization status.

METHODS

This study analyzed data from the first four waves (2013-2018) of the Population Assessment of Tobacco and Health Study, a nationally representative longitudinal survey. The study sample included adolescents (aged 12-17) who reported never used cannabis at baseline. Generalized estimating equations were used to analyze the effect modification of state recreational cannabis law on the association between baseline e-cigarette use and cannabis use at 12-month follow-up, controlling for individual characteristics.

RESULTS

Among adolescents who have never used cannabis at baseline, baseline past-30-day e-cigarette use was significantly associated with past-30-day cannabis use at 12-month follow-up (aOR=5.92, 95% CI: 3.52-9.95). This association was different by state recreational cannabis legalization status, as indicated by the significant interaction term. Subgroup analysis showed that the aOR was 18.39 (95% CI: 4.25-79.68) for adolescents living in states that legalized adult recreational cannabis use and 5.09 (95% CI: 2.86-9.07) for adolescents living in states without such laws.

CONCLUSIONS

E-cigarette use is associated with cannabis initiation among youth. This association is stronger among those living in states that legalized adult recreational cannabis use. Further examination of the impact of e-cigarette use on cannabis initiation in relation to state cannabis laws is warranted.

Adaptive Treatment for Youth With Substance Use and Depression: Early Depression Response and Short-term Outcomes

OBJECTIVE

To investigate prevalence and predictors of early depression response (EDR) in adolescents with substance use and depression receiving cognitive-behavioral therapy (CBT) for substance use and to test the efficacy of supplemental CBT targeting depression (CBT-D) for non-EDR adolescents in an adaptive treatment approach.

METHOD

At 2 sites, 95 youths (ages 14-21, mean [SD] = 17.4 [1.8]) with alcohol or cannabis use and depressive symptoms received up to 12 sessions of CBT for substance use over 14 weeks. Assessments were at baseline and weeks 4, 9, and 14. The Children's Depression Rating Scale-Revised was the primary depression measure, with a reduction of 50% or more on this scale at week 4 defining EDR. The primary substance use outcomes of alcohol use, heavy alcohol use, and cannabis use frequency were assessed via interview report on the Alcohol Consumption Questionnaire and the Drug Checklist. Urinalysis provided a secondary measure of cannabis use. Non-EDR adolescents were randomly assigned to supplemental CBT-D or enhanced treatment as usual (ETAU).

RESULTS

Thirty-five adolescents (37%; 95% CI, 27%-47%) demonstrated EDR. Fewer days of cannabis use (odds ratio 0.977; 95% CI, 0.961-0.992) and absence of conduct disorder (odds ratio 0.149; 95% CI, 0.031-0.716) predicted EDR. Frequency of drinking (F_1,82 = 11.09, η² = 0.119, p = .001), heavy drinking (F_1,82 = 19.91, η² = 0.195, p < .0001), and cannabis use (F_1,220 = 35.01, η² = 0.137, p < .001) decreased over time for EDR, CBT-D, and ETAU adolescents, with EDR adolescents evidencing earlier lower cannabis use (F_2,220 = 4.16, η² = 0.036, p = .0169). Negative (clean) urine screens increased over time (F_1,219 = 5.10, η² = 0.023, p = .0249). Comparison of CBT-D and ETAU indicated that depression significantly decreased over time in both groups (F_1,48 = 64.20, η² = 0.572, p < .001), with no advantage for CBT-D.

CONCLUSION

Approximately one-third of adolescents with substance use and depression attain EDR during substance use treatment. Less frequent cannabis use facilitates depression response. The relatively small sample may have precluded identification of additional EDR predictors.

CLINICAL TRIAL REGISTRATION INFORMATION

Treatment for Teens With Alcohol Abuse and Depression; https://clinicaltrials.gov/; NCT02227589.

Prenatal alcohol and tobacco exposures and the risk of cannabis use in offspring: Findings from a population-based cohort study

BACKGROUND

There is a paucity of prospective longitudinal studies examining the associations between maternal use of alcohol and tobacco during pregnancy and the risk of cannabis use in offspring. The aim of this study was to examine the association between prenatal alcohol and tobacco exposures and offspring cannabis use.

METHODS

Data were from the Raine Study, a longitudinal prospective birth cohort based in Western Australia. Cannabis use at 17 years of age was measured with a self-reported questionnaire developed to capture risky behaviors in adolescents. Associations between prenatal alcohol and tobacco exposures and the risk of cannabis use in offspring were examined using log-binomial regression models, computing relative risk (RR). We also computed the E-values (E) to estimate the extent of unmeasured confounding.

RESULTS

After adjusting for potential confounders, we observed increased risks of cannabis use in offspring exposed to first trimester prenatal alcohol use (RR = 1.38, 95% CI: 1.09-1.75; E = 2.10, CI:1.40) and tobacco use (RR = 1.42, 95% CI: 1.08-1.86; E = 2.19, CI:1.37) as well as third trimester prenatal alcohol use (RR = 1.39, 95% CI: 1.09-1.79; E = 2.13, CI:1.40) and tobacco use (RR = 1.39, 95% CI: 1.09-1.79; E = 2.21, CI:1.34]. We also noted dose-response associations in which risk estimates in offspring increased with the level of exposures to prenatal alcohol and tobacco use.

CONCLUSION

These findings provide epidemiological evidence for effects of prenatal alcohol and tobacco exposures on offspring cannabis use. Although these results should be confirmed by other studies, the present study adds to the mounting evidence suggesting that women should be encouraged to abstain from alcohol and tobacco during pregnancy.

The Construct of Medical and Non-Medical Marijuana—Critical Review

The rising popularity of medical marijuana and its potential therapeutic uses has resulted in passionate discussions that have mainly focused on its possible benefits and applications. Although the concept itself seems promising, the multitude of presented information has noticeable ramifications—terminological chaos being one. This work aimed to synthesize and critically analyze scientific evidence on the therapeutic uses of cannabinoids in the field of psychiatry. Emphasis was placed on the anxiolytic effects of cannabis constituents and their effects on post-traumatic stress disorder, anxiety disorders, schizophrenia spectrum, and other psychotic disorders. The review was carried out from an addictological perspective. A database search of interchangeably combined keywords resulted in the identification of subject-related records. The data were then analyzed in terms of relevance, contents, methodologies, and cited papers. The results were clear in supporting one common conclusion: while most findings provide support for beneficial applications of medical marijuana in psychiatry, no certain conclusions can be drawn until larger-scaled, more methodologically rigorous, and (preferably) controlled randomized trials verify these discoveries.

Youth vaping: a review and update on global epidemiology, physical and behavioral health risks, and clinical considerations

Worldwide, youth electronic cigarette use (vaping) has risen significantly over the past decade. This public health concern has spurred many high-quality studies characterizing country-specific prevalence, risk factors, physical and behavioral health complications, and optimal methods of assessment and counseling for youth vaping. Clinicians remain underexposed to this recent work, limiting translation of evidence into higher quality patient care. This review aims to provide pediatricians and other clinicians working with youth a clinically focused survey of key research findings and considerations based on recent evidence. This narrative review surveys emerging trends in EC use across different countries, reasons for youth vaping, characteristics of vaping materials that promote youth use, associations with combustible cigarette use, relation with cannabis and other illicit substances, physical and behavioral health risks associated with vaping, and methods of assessment, counseling, and intervention for problematic vaping in youth. Since vaping remains a relatively new phenomenon, long-term health consequences remain unknown.Conclusion: Youth vaping is an increasingly well-studied phenomenon with both physical and behavioral health risks. Pediatricians and other youth-focused clinicians can apply the lessons of recent research in work with youth and their families. What is Known: • Youth vaping is an increasingly prevalent public health concern. • Recent research demonstrates physical and behavioral health risks associated with vaping as well as methods for assessment, counseling, and intervention. What is New: • The current review summarizes the latest evidence in a clinically focused framework to facilitate translation of emerging knowledge to practice.

Predictors of Early-Onset Cannabis Use in Adolescence and Risks for Substance Use Disorder Symptoms in Young Adulthood

Early detection of risks for substance use disorders is essential to lifelong health and well-being for some youth. Very early-onset use is proposed as an indicator of risk for substance use disorders, but risk and protective factors related to early-onset use have not been identified. The current study compared risk and protective factors that distinguish early- and late-onset cannabis users from abstainers using data collected from a large community sample. The study also examined onset-group differences in participants’ reports of substance use disorder symptoms a decade later. Heavy episodic drinking (early-onset: OR = 7.29 CI = [1.60, 33.19]) and engagement with peers involved in deviant behaviors (early-onset: OR = 2.50 CI = [1.50, 4.13]) are risk factors for early-onset cannabis use. Protective factors, including parent monitoring (early-onset: OR = 0.73 CI = [0.58, 0.93]), engagement with peers involved in positive behaviors (early-onset: OR = 0.54 CI = [0.39, 0.76]), school engagement (early-onset: OR = 0.83 CI = [0.72, 0.96]), and academic grades (early-onset: OR = 0.37 CI = [0.21, 0.65]) also predicted early versus later onset-group differences. Early age of onset may be distinctly related to risk and protective factors previously associated with risks for substance use in all adolescents.

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.

Association between age of cannabis initiation and gray matter covariance networks in recent onset psychosis

Cannabis use during adolescence is associated with an increased risk of developing psychosis. According to a current hypothesis, this results from detrimental effects of early cannabis use on brain maturation during this vulnerable period. However, studies investigating the interaction between early cannabis use and brain structural alterations hitherto reported inconclusive findings. We investigated effects of age of cannabis initiation on psychosis using data from the multicentric Personalized Prognostic Tools for Early Psychosis Management (PRONIA) and the Cannabis Induced Psychosis (CIP) studies, yielding a total sample of 102 clinically-relevant cannabis users with recent onset psychosis. GM covariance underlies shared maturational processes. Therefore, we performed source-based morphometry analysis with spatial constraints on structural brain networks showing significant alterations in schizophrenia in a previous multisite study, thus testing associations of these networks with the age of cannabis initiation and with confounding factors. Earlier cannabis initiation was associated with more severe positive symptoms in our cohort. Greater gray matter volume (GMV) in the previously identified cerebellar schizophrenia-related network had a significant association with early cannabis use, independent of several possibly confounding factors. Moreover, GMV in the cerebellar network was associated with lower volume in another network previously associated with schizophrenia, comprising the insula, superior temporal, and inferior frontal gyrus. These findings are in line with previous investigations in healthy cannabis users, and suggest that early initiation of cannabis perturbs the developmental trajectory of certain structural brain networks in a manner imparting risk for psychosis later in life.

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

INTRODUCTION

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

Cannabis, schizophrenia genetic risk, and psychotic experiences: a cross-sectional study of 109,308 participants from the UK Biobank

Cannabis is known to produce acute, transient psychotic-like experiences. However, it is unclear whether cannabis disproportionately increases the risk of specific types of psychotic experiences and whether genetic predisposition influences the relationship between cannabis use and psychotic experiences. In this cross-sectional study of 109,308 UK Biobank participants, we examined how schizophrenia polygenic risk modulates the association between self-reported cannabis use and four types of self-reported psychotic experiences (auditory hallucinations, visual hallucinations, persecutory delusions, and delusions of reference). Cohort-wide, we found a strong, dose-dependent relationship between cannabis use and all four types of psychotic experiences, especially persecutory delusions. Cannabis users' psychotic experiences tended to be earlier-onset and cause greater distress than non-users', but were not more likely to lead to help-seeking. Participants with high schizophrenia polygenic risk scores showed stronger associations between cannabis use and auditory hallucinations, visual hallucinations, and delusions of reference, as well as psychotic experiences overall. For instance, cannabis ever-use was associated with 67% greater adjusted odds of delusions of reference among individuals in the top fifth of polygenic risk, but only 7% greater adjusted odds among the bottom fifth. Our results suggest that cannabis use is a predictive risk factor for psychotic experiences, including early-onset and distressing experiences. Individuals genetically predisposed to schizophrenia may be especially vulnerable to psychotic experiences as a result of using cannabis, supporting a long-postulated hypothesis. This study exemplifies the utility of population-scale biobanks for elucidating gene-by-environment interactions relating substance use to neuropsychiatric outcomes and points to the translational potential of using polygenic risk scores to inform personalized harm reduction interventions.

Detrimental effects of adolescent escalating low-dose Δ9 -tetrahydrocannabinol leads to a specific bio-behavioural profile in adult male rats

BACKGROUND AND PURPOSE

Adolescent cannabis use is associated with adult psychopathology. When Δ⁹ -tetrahydrocannabinol (THC), mainly in high doses, is administered to adolescence rats there are also long lasting effects in adults. This study aims to determine the specific adult bio-behavioural profile after adolescent low-dose THC, which better mirrors adolescent recreational cannabis use.

EXPERIMENTAL APPROACH

Adolescent male Sprague-Dawley rats were treated with escalating low-dose of THC. In adulthood, they were evaluated for their spontaneous locomotion, sensorimotor gating, higher order and spatial cognitive functions. Dopaminergic activity and cannabinoid receptor expression were measured in distinct brain regions. Hippocampal neurogenic activity of neural stem cells was determined and protein levels of neuroplasticity-related biomarkers were quantified. Adolescent low-dose THC exposure increased spontaneous open-field activity, without affecting prepulse inhibition and attentional set-shifting performance. Region-specific dopaminergic alterations and CB₁ receptor up-regulation in the prefrontal cortex were observed. Impaired spatial memory, as assessed with the object location task and Morris water maze test, was associated with significantly decreased proliferative activity (SOX2-positive cells), neurogenic potential (decreased doublecortin-positive cells) in the adult hippocampus and defective neuroplasticity, including reduced BDNF expression in the hippocampus and prefrontal cortex.

KEY RESULTS

Our findings reveal the adverse impact of adolescent low-dose THC on the psychomotor profile, dopaminergic neurotransmission, compensatory cannabinoid receptor response, cognition-related neurobiological and behavioural functions.

CONCLUSION AND IMPLICATIONS

Our adolescent low-dose THC animal model does not induce tangible psychotic-like effects, such as those reported in high-dose THC studies, but it impairs cognitive functions and points to hippocampal vulnerability and disrupted neurogenesis.

Retrospective Review of Clozapine Use in Children and Adolescents

OBJECTIVE

Literature describing use of clozapine by children and adolescents is limited. The primary study objective was to assess the patterns of clozapine use in an inpatient child and adolescent population.

METHODS

A retrospective review of child and adolescent inpatients receiving clozapine at a Canadian children's hospital from January 2000 through December 2014 was conducted. Interdisciplinary comprehensive data collection was conducted by experienced clinicians. Baseline population characteristics and psychiatric illness risk factors were captured. Illness symptoms and severity were assessed retrospectively using validated measures including the Brief Psychiatric Rating Scale (BPRS), Children's Global Assessment Scale (CGAS) and Clinical Global Impressions (CGI) scales. Estimated clozapine dosing requirements for each patient to achieve a serum level associated with response was calculated. Clozapine-related adverse events were captured.

RESULTS

Twenty-eight inpatients (64% female) receiving clozapine during the study period were identified. Mean age at clozapine initiation was 15.8 years. Twenty-three patients (82%) were taking clozapine at discharge, and of these, 22 patients (96%) experienced at least minimal improvement in BPRS and CGAS scores. Patients took a mean of 33.1 days from clozapine start to reach their maximum clozapine dosage, a mean maximum of 57% of their estimated clozapine dose requirement. Mean length of stay following clozapine initiation was 60.7 days. We observed a high rate of benign hematological adverse events, but no episodes of severe neutropenia. The majority of patients were of ethnicity associated with high risk for metabolic adverse events.

CONCLUSION

Most hospitalized, treatment-refractory children requiring clozapine clinically improve despite experiencing high, but largely manageable, adverse event rates.

Cross-generational THC Exposure Weakly Attenuates Cocaine's Rewarding Effects in Adult Male Offspring

Adolescents represent a large demographic of marijuana consumers. Regrettably, use during this developmental period has been associated with above average health risks. A growing body of evidence suggests that adolescent drug use in the lifetime of a parent can modify behavior and neurochemistry in descendants without direct exposure. The current study was designed to evaluate the effects of pre-conception THC during adolescence on vulnerability to cocaine in adult male offspring. Male and female rats were given an intermittent THC (0 or 1.5 mg/kg) exposure regimen during the adolescent window and mated with drug group conspecifics in adulthood. F1-THC and F1-Veh pups were cross fostered to drug naïve control dams. In Experiment 1, adult offspring underwent cocaine (0 or 15 mg/kg) locomotor sensitization procedures and showed no effect of parental THC exposure on locomotor activity. In Experiment 2, intravenous catheters were implanted and subjects were tested under a number of reinforcement schedules with cocaine (FR1, FR5, FR10, PR, dose-response, extinction, cue + stress induced reinstatement). F1-THC subjects exhibited a slight decrease in cocaine responding during acquisition and a more rapid extinction, but they failed to produce significant differences on any other measure. These findings indicate that adolescent cannabis use likely has minimal effects on cocaine abuse liability in the next generation.

Effects of early ketamine exposure on cerebral gray matter volume and functional connectivity

Ketamine has been used for medical purposes, most typically as an anesthetic, and recent studies support its use in the treatment of depression. However, ketamine tends to be abused by adolescents and young adults. In the current study, we examined the effects of early ketamine exposure on brain structure and function. We employed MRI to assess the effects of ketamine abuse on cerebral gray matter volume (GMV) and functional connectivity (FC) in 34 users and 19 non-users, employing covariates. Ketamine users were categorized as adolescent-onset and adult-onset based on when they were first exposed to ketamine. Imaging data were processed by published routines in SPM and AFNI. The results revealed lower GMV in the left precuneus in ketamine users, with a larger decrease in the adolescent-onset group. The results from a seed-based correlation analysis show that both ketamine groups had higher functional connectivity between left precuneus (seed) and right precuneus than the control group. Compared to controls, ketamine users showed decreased GMV in the right insula, left inferior parietal lobule, left dorsolateral prefrontal cortex/superior frontal gyrus, and left medial orbitofrontal cortex. These preliminary results characterize the effects of ketamine misuse on brain structure and function and highlight the influence of earlier exposure to ketamine on the development of the brain. The precuneus, a structure of central importance to cerebral functional organization, may be particularly vulnerable to the influences of early ketamine exposure. How these structural and functional brain changes may relate to the cognitive and affective deficits remains to be determined with a large cohort of participants.

Cannabinoid exposure in rat adolescence reprograms the initial behavioral, molecular, and epigenetic response to cocaine

The endocannabinoid system has a modulatory role in brain reward and cognitive processes. It has been hypothesized that repeated interference with endocannabinoid signaling (e.g., through abuse of cannabis or synthetic cannabinoids) can remodel the adolescent brain and make it respond differently to more addictive substances, such as cocaine. In the present study, we demonstrate that a history of synthetic cannabinoid exposure in adolescent animals results in distinct molecular and epigenetic changes following initial exposure to cocaine. These changes were pronounced in the prefrontal cortex and associated with an enhanced response to cocaine’s stimulatory effects. The prefrontal cortex is a brain region that still undergoes maturation in adolescence and its dysfunction contributes to the development of addictions.

The initial response to an addictive substance can facilitate repeated use: That is, individuals experiencing more positive effects are more likely to use that drug again. Increasing evidence suggests that psychoactive cannabinoid use in adolescence enhances the behavioral effects of cocaine. However, despite the behavioral data, there is no neurobiological evidence demonstrating that cannabinoids can also alter the brain’s initial molecular and epigenetic response to cocaine. Here, we utilized a multiomics approach (epigenomics, transcriptomics, proteomics, and phosphoproteomics) to characterize how the rat brain responds to its first encounter with cocaine, with or without preexposure to the synthetic cannabinoid WIN 55,212-2 (WIN). We find that in adolescent (but not in adult) rats, preexposure to WIN results in cross-sensitization to cocaine, which correlates with histone hyperacetylation and decreased levels of HDAC6 in the prefrontal cortex (PFC). In the PFC, we also find that WIN preexposure blunts the typical mRNA response to cocaine and instead results in alternative splicing and chromatin accessibility events, involving genes such as Npas2. Moreover, preexposure to WIN enhances the effects of cocaine on protein phosphorylation, including ERK/MAPK-targets like gephyrin, and modulates the synaptic AMPAR/GluR composition both in the PFC and the nucleus accumbens (NAcc). PFC–NAcc gene network topological analyses, following cocaine exposure, reveal distinct top nodes in the WIN preexposed group, which include PACAP/ADCYAP1. These preclinical data demonstrate that adolescent cannabinoid exposure reprograms the initial behavioral, molecular, and epigenetic response to cocaine.

Exploring Cannabis-Specific Parenting as a Mechanism of the Intergenerational Transmission of Cannabis Use and Cannabis Use Disorder

OBJECTIVE

Parental cannabis use disorder (CUD) is a known risk factor in the development of adolescent cannabis use. One potential mechanism is parenting behaviors. This study considered cannabis-specific parenting strategies as a mechanism of the relation between parental CUD and adolescent cannabis use.

METHOD

Pathways were examined using multilevel longitudinal mediation models (N = 363, mean age = 16.3 years) comparing adolescent offspring of parents who never used cannabis, parents who used cannabis without CUD, and parents with CUD.

RESULTS

Parental cannabis use history did not significantly predict parental sharing of negative experiences with cannabis or parental strategies to prevent cannabis use. Cannabis-specific strategies did not successfully deter adolescent use. Parental sharing of negative experiences with cannabis use in fact predicted increased adolescent cannabis use.

CONCLUSIONS

Cannabis-specific parenting did not reduce adolescent cannabis use, and sharing negative experiences was detrimental. Future studies should consider alternative mechanisms underlying the intergenerational transmission of cannabis use.

Mapping cannabis potency in medical and recreational programs in the United States

Cannabis related online searches are associated with positive attitudes toward medical cannabis, particularly when information is obtained from dispensaries. Since pain is the main reason for medicinal cannabis use, information from dispensary websites has the potential to shape the attitude of pain patients towards cannabis. This is relevant because cannabis has demonstrated efficacy in neuropathic pain with low tetrahydrocannabinol (THC) concentrations (< 5-10%), in contrast to potent cannabis (>15% THC), which is highly rewarded in the recreational realm. The role of CBD in pain is not clear, however it has gained popularity. Thus, we hypothesize that the potency of medical cannabis that is advertised online is similar to the cannabis advertised for recreational purposes, which would potentially create a misconception towards medical cannabis. The current lack of knowledge surrounding advertised potencies in the legal cannabis market limits the ability to generate clear policies regarding online advertising to protect patients that are willing to use cannabis for their condition. Thus, we evaluated the advertised THC and CBD content of cannabis products offered online in dispensaries in the United States to determine products' suitability to medicinal use and compare the strength of products offered in legal medical and recreational programs. We recorded THC and CBD concentrations for all herb cannabis products provided by dispensary websites and compared them between or within states. Four Western states (CA, CO, NM, WA) and five Northeastern states (ME, MA, NH, RI, VT) were included. A total of 8,505 cannabis products across 653 dispensaries were sampled. Despite the clear differences between medicinal and recreational uses of cannabis, the average THC concentration advertised online in medicinal programs was similar (19.2% ±6.2) to recreational programs (21.5% ±6.0) when compared between states with different programs, or between medicinal and recreational programs within the same states (CO or WA). Lower CBD concentrations accompanied higher THC products. The majority of products, regardless of medicinal or recreational programs, were advertised to have >15% THC (70.3% - 91.4% of products). These stated concentrations seem unsuitable for medicinal purposes, particularly for patients with chronic neuropathic pain. Therefore, this information could induce the misconception that high potency cannabis is safe to treat pain. This data is consistent with reports in which THC and CBD in products from legal dispensaries or in nationwide products from the illegal market were actually measured, which indicates that patients consuming these products may be at risk of acute intoxication or long-term side effects. Our study offers grounds to develop policies that help prevent misconceptions toward cannabis and reduce risks in pain patients.

Psychotic symptoms are associated with lower cortical folding in youth at risk for mental illness

BACKGROUND

Cortical folding is essential for healthy brain development. Previous studies have found regional reductions in cortical folding in adult patients with psychotic illness. It is unknown whether these neuroanatomical markers are present in youth with subclinical psychotic symptoms.

METHODS

We collected MRIs and examined the local gyrification index in a sample of 110 youth (mean age ± standard deviation 14.0 ± 3.7 yr; range 9–25 yr) with a family history of severe mental illness: 48 with psychotic symptoms and 62 without. Images were processed using the Human Connectome Pipeline and FreeSurfer. We tested for group differences in local gyrification index using mixed-effects generalized linear models controlling for age, sex and familial clustering. Sensitivity analysis further controlled for intracranial volume, IQ, and stimulant and cannabis use.

RESULTS

Youth with psychotic symptoms displayed an overall trend toward lower cortical folding across all brain regions. After adjusting for multiple comparisons and confounders, regional reductions were localized to the frontal and occipital lobes. Specifically, the medial (B = –0.42, pFDR = 0.04) and lateral (B = –0.39, pFDR = 0.04) orbitofrontal cortices as well as the cuneus (B = –0.47, pFDR = 0.03) and the pericalcarine (B = –0.45, pFDR = 0.03) and lingual (B = –0.38, pFDR = 0.04) gyri.

LIMITATIONS

Inference about developmental trajectories was limited by the cross-sectional data.

CONCLUSION

Psychotic symptoms in youth are associated with cortical folding deficits, even in the absence of psychotic illness. The current study helps clarify the neurodevelopmental basis of psychosis at an early stage, before medication, drug use and other confounds have had a persistent effect on the brain.

Cannabis use and nonuse in patients with first-episode psychosis: A systematic review and meta-analysis of studies comparing neurocognitive functioning

BACKGROUND

The implications of cannabis use in the onset of early psychosis and the severity of psychotic symptoms have resulted in a proliferation of studies on this issue. However, few have examined the effects of cannabis use on the cognitive symptoms of psychosis (i.e., neurocognitive functioning) in patients with first-episode psychosis (FEP). This systematic review and meta-analysis aim to assess the neurocognitive functioning of cannabis users (CU) and nonusers (NU) with FEP.

METHODS

Of the 110 studies identified through the systematic review of 6 databases, 7 met the inclusion criteria, resulting in 14 independent samples and 78 effect sizes. The total sample included 304 CU with FEP and 369 NU with FEP. The moderator variables were age at first use, duration of use, percentage of males, and age.

RESULTS

Effect sizes were not significantly different from zero in any neurocognitive domain when users and NU were compared. Part of the variability in effect sizes was explained by the inclusion of the following moderator variables: (1) frequency of cannabis use (β = 0.013, F = 7.56, p = 0.017); (2) first-generation antipsychotics (β = 0.019, F = 34.46, p ≤ 0.001); and (3) country where the study was carried out (β = 0.266, t = 2.06, p = 0.043).

CONCLUSIONS

This meta-analysis indicates that cannabis use is not generally associated with neurocognitive functioning in patients with FEP. However, it highlights the deleterious effect of low doses of cannabis in some patients. It also stresses the importance of the type of antipsychotic prescription and cannabis dose as moderator variables in the neurocognitive functioning of CU with FEP.

Media use during adolescence: the recommendations of the Italian Pediatric Society

Background

The use of media device, such as smartphone and tablet, is currently increasing, especially among the youngest. Adolescents spend more and more time with their smartphones consulting social media, mainly Facebook, Instagram and Twitter because. Adolescents often feel the necessity to use a media device as a means to construct a social identity and express themselves. For some children, smartphone ownership starts even sooner as young as 7 yrs, according to internet safety experts.

Material and methods

We analyzed the evidence on media use and its consequences in adolescence.

Results

In literature, smartphones and tablets use may negatively influences the psychophysical development of the adolescent, such as learning, sleep and sigh. Moreover, obesity, distraction, addiction, cyberbullism and Hikikomori phenomena are described in adolescents who use media device too frequently. The Italian Pediatric Society provide action-oriented recommendations for families and clinicians to avoid negative outcomes.

Conclusions

Both parents and clinicians should be aware of the widespread phenomenon of media device use among adolescents and try to avoid psychophysical consequences on the youngest.

Association Between Electronic Cigarette Use and Marijuana Use Among Adolescents and Young Adults: A Systematic Review and Meta-analysis

IMPORTANCE

Use of electronic cigarettes (often called e-cigarettes) has increased considerably among young people in the past 5 years. Use of e-cigarettes has been associated with higher rates of marijuana use, which is associated with several adverse health outcomes in youth.

OBJECTIVE

To characterize and quantify the association between e-cigarette and marijuana use among youth using a meta-analysis.

DATA SOURCES

PubMed, Embase, and Web of Science & ProQuest Dissertations and Theses were searched from inception to October 2018. A gray-literature search was also conducted on conference abstracts, government reports, and other sources.

STUDY SELECTION

Included studies compared rates of marijuana use among youth aged 10 to 24 years who had used e-cigarettes vs those who had not used e-cigarettes. Two reviewers independently assessed studies for inclusion; disagreements were discussed with a third reviewer and resolved by consensus.

DATA EXTRACTION AND SYNTHESIS

Data were extracted by 2 independent reviewers following Meta-analyses of Observational Studies in Epidemiology (MOOSE) reporting guidelines and pooled using a random-effects analysis. The Newcastle-Ottawa Scale was used to assess data quality and validity of individual studies.

MAIN OUTCOMES AND MEASURES

Adjusted odds ratios (AORs) of self-reported past or current marijuana use by youth with vs without past or current e-cigarette use.

RESULTS

Twenty-one of 835 initially identified studies (2.5%) met selection criteria. The meta-analysis included 3 longitudinal and 18 cross-sectional studies that included 128 227 participants. Odds of marijuana use were higher in youth who had an e-cigarette use history vs those who did not (AOR, 3.47 [95% CI, 2.63-4.59]; I2, 94%). Odds of marijuana use were significantly increased in youth who used e-cigarettes in both longitudinal studies (3 studies; AOR, 2.43 [95% CI, 1.51-3.90]; I2, 74%) and cross-sectional studies (18 studies; AOR, 3.70 [95% CI, 2.76-4.96]; I2, 94%). Odds of using marijuana in youth with e-cigarette use were higher in adolescents aged 12 to 17 years (AOR, 4.29 [95% CI, 3.14-5.87]; I2, 94%) than young adults aged 18 to 24 years (AOR, 2.30 [95% CI, 1.40-3.79]; I2, 91%).

CONCLUSIONS AND RELEVANCE

This meta-analysis found a significant increase in the odds of past or current and subsequent marijuana use in adolescents and young adults who used e-cigarettes. These findings highlight the importance of addressing the rapid increases in e-cigarette use among youths as a means to help limit marijuana use in this population.

Does the Fast Track Intervention Prevent Later Psychosis Symptoms?

The Fast Track (FT) intervention was a multimodal preventive intervention addressing antisocial development across 10 years of childhood and early adolescence. The intervention included parent management training, child social-cognitive skills training, peer coaching and mentoring, academic skills tutoring, and a classroom social-emotional learning program. While not specifically designed to target psychosis symptoms (e.g., social withdrawal, thought abnormalities), the present study aimed to examine whether the FT intervention prevented psychosis symptoms through childhood and adolescence and into adulthood. Participants included the FT intervention and high-risk control samples (N = 891; 69% male; M age = 6.58 years, SD = .48). Psychosis symptoms were assessed using the "thought problems" subscale of the parent-report Child Behavior Checklist during grades 1, 2, 4, 5, and 7, and the self-report Adult Behavior Checklist at age 25 years, in line with prior research using this measure. Growth models included the FT condition and covariates (i.e., initial risk screen score, cohort, socioeconomic status, rural/urban status, race, and sex) as predictors; and child, adolescent, and adult psychosis symptoms as outcomes. Intervention status was not significantly associated with the slope of psychosis symptoms; however, after controlling for concurrent cannabis use, intervention participants reported lower levels of psychosis symptoms over time. Findings suggest that interventions targeting antisocial behavior may prevent psychosis symptoms in the long term.

What Every Pediatric Gynecologist Should Know About Marijuana Use in Adolescents

Use of marijuana in adolescent girls is common and shows no sign of decreasing. With recent trends toward legalization of "recreational" and "medical" marijuana products, adolescents are increasingly faced with information and misinformation about the health effects of marijuana use. We review the current literature on the risks and potential benefits of marijuana use during adolescence with a specific focus on pediatric and adolescent gynecological conditions. Despite limited research on this topic, the many risks associated with marijuana use in adolescents, including negative effects on the developing brain and adverse reproductive, sexual health, and mental health outcomes, likely outweigh potential benefits in this population.

Adolescent inhalant use and psychosis risk - a prospective longitudinal study

BACKGROUND

Cross-sectional studies have suggested inhalant use is associated with psychosis. This association was examined in a longitudinal study accounting for other substance use and potential confounders.

METHODS

We used a prospective sample (N = 6542) from the Northern Finland Birth Cohort 1986. Self-report questionnaires on substance use and psychotic experiences were completed when the cohort members were 15-16 years old. Inhalant use was categorized into four groups (never, once, 2-4 times, 5 times or more). Subsequent psychosis diagnoses (ICD-10) until age 30 years were obtained from national registers. Cox regression analysis was used to examine the association between adolescent inhalant use and risk of psychosis.

RESULTS

During the observation period 124 individuals were diagnosed with incident psychosis. Overall, there were 225 (3.4%) subjects with any inhalant use, 18 (8.0%) of whom were diagnosed with psychosis during the follow up. Of non-inhalant users (n = 6317) 106 (1.7%) were diagnosed with psychosis. Compared to non-users, those using inhalants had increased risk of incident psychosis with most frequent inhalant use associated with the greatest risk (unadjusted HR = 9.46; 3.86-23.20). After adjusting for baseline psychotic experiences, other substance use, comorbid mental disorder and parental substance abuse, the increased risk of psychosis persisted (HR = 3.06; 1.05-8.95). Furthermore, a dose-response effect between inhalant use and risk of psychosis was identified (OR = 2.34; 1.83-2.99).

CONCLUSIONS

Inhalant use in adolescence was independently associated with incident psychosis. The adverse health outcomes associated with adolescent inhalant use provide compelling reasons for implementation of policies to reduce the use of volatile substances in adolescents.

Maternal Cannabis Use During a Child's Lifetime Associated With Earlier Initiation

INTRODUCTION

Earlier cannabis initiation is associated with more severe neuropsychiatric and social consequences. The authors investigated whether mothers' cannabis use is associated with earlier cannabis initiation by their children.

METHODS

Mother and child data were from the National Longitudinal Survey of Youth 1979 (1980-1998 waves) and Child and Young Adults (1988-2014 waves) cohorts, respectively. Cox proportional hazard models assessed the effect of maternal cannabis use prior to a child's adolescence on the child's risk of subsequent cannabis initiation. Models were stratified by race and child's age category (6-16, 17-24, ≥25 years). Adjusted analyses controlled for sociodemographic variables. Analyses were conducted in 2017.

RESULTS

Median age of cannabis initiation for children of maternal ever users was age 16years compared with age 18years among children of maternal never users. Children of 1-year and multiple-year users were at increased risk of cannabis initiation between ages 6 and 16years (hazard ratio=1.38, p<0.001, and hazard ratio = 1.45, p<0.001, respectively). Effects were slightly stronger among non-Hispanic non-black children.

CONCLUSIONS

As cannabis legalization expands across the U.S., adult use may become increasingly normative. This study indicates that maternal cannabis use may be a risk factor for early initiation among their offspring. Preventive interventions should consider strategies to delay initiation among children of cannabis users.

Orbitofrontal connectivity is associated with depression and anxiety in marijuana-using adolescents

BACKGROUND

Prevalence of marijuana (MJ) use among adolescents has been on the rise. MJ use has been reported to impact several brain regions, including frontal regions such as the orbitofrontal cortex (OFC). The OFC is involved in emotion regulation and processing and has been associated with symptoms of depression and anxiety. Therefore, we hypothesized that adolescent MJ users would show disruptions in OFC connectivity compared with healthy adolescents (HC) which would be associated with symptoms of mood and anxiety.

METHODS

43 MJ-using and 31 HC adolescents completed clinical measures including the Hamilton Anxiety Scale (HAM-A) and Hamilton Depression Rating Scale (HAM-D). Resting-state functional magnetic resonance imaging data was also acquired for all participants.

RESULTS

In MJ users, increased depressive symptoms were associated with increased connectivity between the left OFC and left parietal regions. In contrast, lower ratings of anxiety were associated with increased connectivity between right and left OFC and right occipital and temporal regions. These findings indicate significant differences in OFC connectivity in MJ-using adolescents, which correlated with mood/anxiety.

LIMITATIONS

Future studies with an increased number of female participants is required to address potential sex differences in connectivity patterns related to symptoms of depression and anxiety.

CONCLUSIONS

This study highlights the association between OFC connectivity, MJ use, and symptoms of depression and anxiety in adolescents. These findings provide further insight into understanding the neural correlates that modulate the relationship between comorbid MJ use and mood disorders and could potentially help us better develop preventive and treatment measures.

G protein-coupled receptor heteromers are key players in substance use disorder

G protein-coupled receptors (GPCR) represent the largest family of membrane proteins in the human genome. Physical association between two different GPCRs is linked to functional interactions which generates a novel entity, called heteromer, with specific ligand binding and signaling properties. Heteromerization is increasingly recognized to take place in the mesocorticolimbic pathway and to contribute to various aspects related to substance use disorder. This review focuses on heteromers identified in brain areas relevant to drug addiction. We report changes at the molecular and cellular levels that establish specific functional impact and highlight behavioral outcome in preclinical models. Finally, we briefly discuss selective targeting of native heteromers as an innovative therapeutic option.

Current, future and potential use of mobile and wearable technologies and social media data in the ABCD study to increase understanding of contributors to child health

Mobile and wearable technologies and novel methods of data collection are innovating health-related research. These technologies and methods allow for multi-system level capture of data across environmental, physiological, behavioral, and psychological domains. In the Adolescent Brain Cognitive Development (ABCD) Study, there is great potential for harnessing the acceptability, accessibility, and functionality of mobile and social technologies for in-vivo data capture to precisely measure factors, and interactions between factors, that contribute to childhood and adolescent neurodevelopment and psychosocial and health outcomes. Here we discuss advances in mobile and wearable technologies and methods of analysis of geospatial, ecologic, social network and behavioral data. Incorporating these technologies into the ABCD study will allow for interdisciplinary research on the effects of place, social interactions, environment, and substance use on health and developmental outcomes in children and adolescents.