Dare to delay? The impacts of adolescent alcohol and marijuana use onset on cognition, brain structure, and function

ISRIB ameliorates spatial learning and memory impairment induced by adolescent intermittent ethanol exposure in adult male rats

Alcohol exposure in adolescence is considered a major cause of cognitive impairments later in life including spatial learning and memory. Integrated stress response (ISR), a program of conservative translation and transcription, is crucial in synaptic plasticity and memory. Although previous studies have elucidated ISR in different brain areas involved in learning and memory disorders, the impact of ISR on learning and memory following adolescent alcohol exposure remains unclear. Here, we demonstrated that adolescent intermittent ethanol (AIE) exposure caused spatial learning and memory impairment, combined with neuronal damage in the medial prefrontal cortex (mPFC), nucleus accumbens (NAc) and hippocampus (HIP) in adult rats. Moreover, integrated stress response inhibitor (ISRIB) administration not only improved spatial learning and memory impairment and neuronal damage but also inhibited the endoplasmic reticulum stress (ER) and reversed changes in synaptic proteins. These findings suggested that ISRIB ameliorates AIE exposure-induced spatial learning and memory deficits by improving neural morphology and synaptic function through inhibiting ER stress signaling pathway in the mPFC, NAc and HIP in adulthood. Our findings may enhance comprehension of cognitive function and neuronal effects of adolescent ethanol exposure and ISRIB treatment may be an underlying potential option for addressing alcohol-induced learning and memory deficits.

Cannabinoids Used for Medical Purposes in Children and Adolescents: A Systematic Review and Meta-Analysis

Importance

Cannabinoids are increasingly used for medical purposes in children. Evidence of the safety of cannabinoids in this context is sparse, creating a need for reliable information to close this knowledge gap.

Objective

To study the adverse event profile of cannabinoids used for medical purposes in children and adolescents.

Data Sources

For this systematic review and meta-analysis, MEDLINE, Embase, PsycINFO, and the Cochrane Library were searched for randomized clinical trials published from database inception to March 1, 2024, for subject terms and keywords focused on cannabis and children and adolescents. Search results were restricted to human studies in French or English.

Study Selection

Two reviewers independently performed the title, abstract, and full-text review, data extraction, and quality assessment. Included studies enrolled at least 1 individual 18 years or younger, had a natural or pharmaceutical cannabinoid used as an intervention to manage any medical condition, and had an active comparator or placebo.

Data Extraction and Synthesis

Two reviewers performed data extraction and quality assessment independently. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline and PRISMA-S guideline were used. Data were pooled using a random-effects model.

Main Outcomes and Measures

The primary outcome was the incidence of withdrawals, withdrawals due to adverse events, overall adverse events, and serious adverse events in the cannabinoid and control arms. Secondary outcomes were the incidence of specific serious adverse events and adverse events based on organ system involvement.

Results

Of 39 175 citations, 23 RCTs with 3612 participants were included (635 [17.6%] female and 2071 [57.3%] male; data not available from 2 trials); 11 trials (47.8%) included children and adolescents only, and the other 12 trials (52.2%) included children, adolescents, and adults. Interventions included purified cannabidiol (11 [47.8%]), nabilone (4 [17.4%]), tetrahydrocannabinol (3 [13.0%]), cannabis herbal extract (3 [13.0%]), and dexanabinol (2 [8.7%]). The most common indications were epilepsy (9 [39.1%]) and chemotherapy-induced nausea and vomiting (7 [30.4%]). Compared with the control, cannabinoids were associated with an overall increased risk of adverse events (risk ratio [RR], 1.09; 95% CI, 1.02-1.16; I2 = 54%; 12 trials), withdrawals due to adverse events (RR, 3.07; 95% CI, 1.73-5.43; I2 = 0%; 14 trials), and serious adverse events (RR, 1.81; 95% CI, 1.21-2.71; I2 = 59%; 11 trials). Cannabinoid-associated adverse events with higher RRs were diarrhea (RR, 1.82; 95% CI, 1.30-2.54; I2 = 35%; 10 trials), increased serum levels of aspartate aminotransferase (RR, 5.69; 95% CI, 1.74-18.64; I2 = 0%; 5 trials) and alanine aminotransferase (RR, 5.67; 95% CI, 2.23-14.39; I2 = 0%; 6 trials), and somnolence (RR, 2.28; 95% CI, 1.83-2.85; I2 = 8%; 14 trials).

Conclusions and Relevance

In this systematic review and meta-analysis, cannabinoids used for medical purposes in children and adolescents in RCTs were associated with an increased risk of adverse events. The findings suggest that long-term safety studies, including those exploring cannabinoid-related drug interactions and tools that improve adverse event reporting, are needed.

Neurological Disorders Induced by Drug Use: Effects of Adolescent and Embryonic Drug Exposure on Behavioral Neurodevelopment

Clinical studies demonstrate that the risk of developing neurological disorders is increased by overconsumption of the commonly used drugs, alcohol, nicotine and cannabis. These drug-induced neurological disorders, which include substance use disorder (SUD) and its co-occurring emotional conditions such as anxiety and depression, are observed not only in adults but also with drug use during adolescence and after prenatal exposure to these drugs, and they are accompanied by long-lasting disturbances in brain development. This report provides overviews of clinical and preclinical studies, which confirm these adverse effects in adolescents and the offspring prenatally exposed to the drugs and include a more in-depth description of specific neuronal systems, their neurocircuitry and molecular mechanisms, affected by drug exposure and of specific techniques used to determine if these effects in the brain are causally related to the behavioral disturbances. With analysis of further studies, this review then addresses four specific questions that are important for fully understanding the impact that drug use in young individuals can have on future pregnancies and their offspring. Evidence demonstrates that the adverse effects on their brain and behavior can occur: (1) at low doses with short periods of drug exposure during pregnancy; (2) after pre-conception drug use by both females and males; (3) in subsequent generations following the initial drug exposure; and (4) in a sex-dependent manner, with drug use producing a greater risk in females than males of developing SUDs with emotional conditions and female offspring after prenatal drug exposure responding more adversely than male offspring. With the recent rise in drug use by adolescents and pregnant women that has occurred in association with the legalization of cannabis and increased availability of vaping tools, these conclusions from the clinical and preclinical literature are particularly alarming and underscore the urgent need to educate young women and men about the possible harmful effects of early drug use and to seek novel therapeutic strategies that might help to limit drug use in young individuals.

Nicotine and Alcohol Use as Predictors of Recreational Cannabis Use in Adolescence: A Systematic Review and Narrative Synthesis

Background: The prevalence of recreational cannabis use among adolescents is a growing public health concern due to its link to short- and long-term adverse effects on adolescents' wellbeing, physical health, mental health, and interpersonal behaviors. Method: Five databases were searched from inception to March 17, 2023, for exposure (nicotine product, alcohol) and outcome (recreational cannabis) in adolescents (persons aged 10-19 years). The studies were screened independently by two reviewers, and the quality of the studies was assessed with Newcastle Ottawa and AXIS tool. PRISMA guidelines were employed in this review. Result: Twenty-one (21) studies involving 2,778,406 adolescents were included in the appraisal and heterogeneity was found among these studies. Ascertainment bias was commonly detected in thirteen (13) of the included studies. Among the substances examined as potential exposures, nicotine-product use emerged as a significant factor associated with future cannabis use among adolescents, particularly in mid-adolescence and in places where recreational cannabis use has been legalized. Conclusion: Current evidence suggests an association between nicotine-product use and subsequent recreational cannabis use among adolescents. However, further research is needed to establish causality between exposure to nicotine substances and the use of recreational cannabis within this age demographic. Additionally, there is a need for the development of prevention programs and targeted policies that continuously inform and update this vulnerable sub-population about the risks associated with cannabis use for leisure.

Neurite Orientation Dispersion and Density Imaging (NODDI) of Brain Microstructure in Adolescent Cannabis and Nicotine Use

INTRODUCTION

Despite evidence suggesting deleterious effects of cannabis and nicotine tobacco product (NTP) use on white matter integrity, there have been limited studies examining white matter integrity among users of both cannabis and nicotine. Further, updated white matter methodology provides opportunities to investigate use patterns on neurite orientation dispersion and density (NODDI) indices and subtle tissue changes related to the intra- and extra-neurite compartment. We aimed to investigate how cannabis and NTP use among adolescents and young adults interacts to impact the white matter integrity microstructure.

MATERIALS AND METHODS

A total of 221 participants between the ages of 16 and 22 completed the Customary Drinking and Drug Use Record (CDDR) to measure substance use, and underwent a magnetic resonance imaging (MRI) session. Participants were divided into NTP-control and NTP groupings and cannabis-control and cannabis groupings (≥26 NTP/cannabis uses in past 6 months). Tract-Based Spatial Statistics (TBSS) and two-way between-subjects ANOVA investigated the effects of NTP use group, cannabis use group, and their interaction on fractional anisotropy (FA) and NODDI indices while controlling for age and biological sex.

RESULTS

NTP use was associated with decreased FA values and increased orientation dispersion in the left anterior capsule. There were no significant effects of cannabis use or the interaction of NTP and cannabis use on white matter outcomes.

DISCUSSION

NTP use was associated with altered white matter integrity in an adolescent and young adult sample. Findings suggest that NTP-associated alterations may be linked to altered fiber tract geometry and dispersed neurite structures versus myelination, as well as differential effects of NTP and cannabis use on white matter structure. Future work is needed to investigate how altered white matter is related to downstream behavioral effects from NTP use.

Alcohol initiation before age 15 predicts earlier hazardous drinking: A survival analysis of a 7-year prospective longitudinal cohort of Australian adolescents

BACKGROUND AND AIMS

Early alcohol use may predict later alcohol problems, but the magnitude of this effect and impact of delayed onset remain uncertain. This study measured age-based differences in progression from first full alcoholic drink to hazardous drinking in one of the largest and most recent prospective cohorts of Australian adolescents.

DESIGN, SETTINGS, PARTICIPANTS AND MEASUREMENT

A 7-year (2012-19) prospective longitudinal cohort of 2082 Australian adolescents was established from the Climate and Preventure (cohort 1) and Climate Schools Combined (cohort 2) studies. Participants completed surveys annually from ages 13 to 20 years. Interval censored survival analyses were conducted with first episode of hazardous drinking [three or more on proxy Alcohol Use Disorders Identification Test (AUDIT-C)] as the survival end-point, controlling for age, sex and mental health symptomatology. Onset of hazardous drinking was expressed as hazard ratios (HRs), and median survival time (years) was used to model first onset of hazardous alcohol use in survival curves.

FINDINGS

Compared with those aged 15 or older, those who had their first full drink at 12 or younger had significantly elevated risk of hazardous drinking onset during the study period [log (HR): 9.3; 95% confidence interval (CI) = 7.0-12.0, P < 0.001]. Compared with those who had their first full drink at ages 13-14, those who delayed until 15 or older had significantly later onset of hazardous drinking; 1.63 years for males (95% CI = 1.31-1.92, P < 0.001) and 1.50 for females (95% CI = 1.15-1.81, P < 0.001), resulting in a median age of onset of hazardous drinking of > 19 for both sexes (male: 19.05 years, 95% CI = 18.74-19.38; female: 19.47 years, 95% CI = 19.19-19.75). First drink at ages 13-14 was associated with the earliest onset of hazardous drinking (males: 17.43 years; females: 17.98 years).

CONCLUSIONS

In Australia, alcohol initiation prior to age 15 appears to be associated with an earlier onset of hazardous drinking than initiation after age 15.

Impact of Cannabis Legalization on Adolescent Cannabis Use

Because of substantial limitations in available national data, such as inconsistencies among surveys and small sample sizes, the increased prevalence of cannabis use among adolescents since recreational legalization has not been directly observed. Nevertheless, both usage frequency and product potency have significantly increased, alongside alternative routes of delivery to smoking, such as vaping cannabis. Moreover, certain populations may be especially vulnerable to the effects of legalization. Regardless of differing state-level cannabis legalization status, the adverse consequences of cannabis on youth have clear negative impacts on mental health, medical symptoms, educational outcomes, and increased risk of addiction to other substances.

Impact of Adolescent Cannabis Use on Neurocognitive and Brain Development

Research examining associations between frequent cannabis use in adolescence and brain-behavior outcomes has increased substantially over the past 2 decades. This review attempts to synthesize the state of evidence in this area of research while acknowledging challenges in interpretation. Although there is converging evidence that ongoing, frequent cannabis use in adolescence is associated with small reductions in cognitive functioning, there is still significant debate regarding the persistence of reductions after a period of abstinence. Similarly, there is controversy regarding the replicability of structural and functional neuroimaging findings related to frequent cannabis use in adolescence. Larger studies with informative designs are needed.

Prevention of hazardous use of alcohol among high school students: a study protocol for the randomized controlled trial 'Our choice'

BACKGROUND

Adolescent hazardous alcohol use is prevalent and has serious short- and long-term consequences. The trial 'Our Choice' examines efficacy, feasibility and acceptability of prevention interventions targeting school, parent, and student levels at Danish high schools. We hypothesize that students in a structural intervention (school and parent levels) reduce hazardous alcohol use and related health behaviors compared to students in an assessment only control group 12 months post baseline; and that adding group-based Motivational Interviewing (group MI) yields further improvements. The study examines the efficacy of interventions targeting multiple levels with the aim of providing novel insights into prevention of adolescent hazardous alcohol use and related health outcomes.

METHOD

The study employs a parallel group cluster randomized controlled trial design with three conditions: (1) structural condition targeting school and parent levels, (2) structural condition combined with group MI which also targets the student level, and (3) assessment-only control condition. A participatory approach is used to adapt and develop interventions. Sixteen high schools in Denmark and about N = 3100 first-year students (15-18 years) enrolled in high school in August 2023 will be recruited. Data will be collected via online questionnaires pre-interventions (baseline), 2, 6, 9 and 12 month post baseline and analyzed with generalized linear mixed models. The primary outcome is past month high intensity drinking; secondary outcomes are alcohol use, alcohol-related consequences, well-being, tobacco, and illegal substance use. Feasibility and acceptability will be assessed via surveys (students) and interviews (high school staff) to inform future implementation.

DISCUSSION

'Our Choice' is the first trial to compare the efficacy of a structural intervention targeting school- and parent levels to an intervention targeting these levels and the student level via group MI - on hazardous drinking and related health outcomes among students. Preventing and reducing hazardous alcohol use during adolescence is crucial due to the short- and long-term negative consequences. The tested interventions can be implemented at low cost. The study has significant implications for adolescent health and well-being and has potential to inform evidence-based decisions on alcohol prevention policy, education, and health professions.

TRIAL REGISTRATION NUMBER

The trial was retrospectively registered at ClinicalTrials.gov on August 24th, 2023.

TRIAL REGISTRATION NUMBER

ID NCT06018389.

Prevalence of parental supply of alcohol to minors: a systematic review

Parental supply of alcohol to minors (i.e. those under the legal drinking age) is often perceived by parents as protective against harms from drinking, despite evidence linking it with adverse alcohol-related outcomes. This systematic review describes the prevalence of parental supply of alcohol, as reported in the international literature. The review was registered with PROSPERO (CRD42020218754). We searched seven online databases (Medline, Embase, PsycINFO, CINAHL, Scopus, Web of Science and Public Health Database) and grey literature from January 2011 to December 2022 and assessed the risk of bias with the JBI Critical Appraisal Checklist. Among 58 articles included in narrative synthesis from 29 unique datasets, there was substantial variation in the definition and measurement of parental supply of alcohol. Overall prevalence rates ranged from 7.0 to 60.0% for minor-report samples, and from 24.0 to 48.0% for parent-report samples. Data indicate that parental supply prevalence is generally proportionately higher for older minors or later-stage students, for girls, and has increased over time among minors who report drinking. Literature on the prevalence of parental supply of alcohol is robust in quantity but inconsistent in quality and reported prevalence. Greater consistency in defining and measuring parental supply is needed to better inform health promotion initiatives aimed at increasing parents' awareness.

Long-Term RCT outcomes for adolescent alcohol and cannabis use within a predominantly Hispanic sample

Because adolescents are unlikely to seek, receive, or complete treatment for alcohol and/or cannabis misuse, it is important to enhance the lasting impact of clinical contacts when they do occur. Adolescents (N = 506; 72.5% Hispanic) were randomized to motivational interviewing (MI) versus alcohol and cannabis education (ACE). Latent growth models estimated change over time. Significant reductions in alcohol use were observed, with slightly greater reductions by 12-month follow-up for MI. Both interventions significantly reduced cannabis use, with no treatment group differences. When outcomes were examined comparing Hispanic to non-Hispanic participants, there were no significant differences in intervention efficacy by group. MI's inherently client-centered and culturally adaptive approach may contribute to its equitable degree of behavior change for youth across race/ethnic backgrounds.

Adverse childhood experiences and alcohol use and misuse: Testing the impact of traditional and expanded adverse childhood experiences among racially/ethnically diverse youth transitioning into adulthood

Objective

Traditional Adverse Childhood Experiences (T-ACEs), such as abuse and neglect, have been associated with an increased risk of youth alcohol use and misuse. This study aims to compare associations of T-ACEs and Expanded ACEs (E-ACEs), an expanded set of ACEs that encompass community-level adversities, with alcohol use and misuse by race/ethnicity.

Method

Data came from a three-wave (1998-1999; 1999-2000; 2004-2005) community-based study in Houston, including youth transitioning into adulthood. We compared associations between ACEs at Wave 1 and past-year alcohol use, abuse, and dependence at Wave 3.

Results

Participants (n = 2,391) included White (n =908), Black (n = 898) and Latinx (n = 585) youth (M (SD) = 14.00 (2.04)) transitioning into young adulthood (M (SD) = 19.77 (2.34)). T-ACEs were associated with higher odds of alcohol use, abuse, and dependence (OR = 1.15, OR = 1.18, OR = 1.24, respectively) while E-ACEs increased the odds of alcohol dependence (OR = 1.23) in the total sample. No significant differences by race/ethnicity were found. Racial/ethnic differences in increased alcohol risk were observed for some ACE items, such as bullying and use for Latinx youth (OR = 2.13) and poverty and dependence for White youth (OR = 2.01).

Conclusions

T-ACES and E-ACEs increase the risk of alcohol use and misuse. Results highlight the importance of preventing ACEs exposure as a risk factor for youth alcohol use and misuse. Public policies must also focus on preventing ACEs through multi-level interventions aimed at reducing violence, bullying, and financial instability.

Do non-drinking youth drink less alcohol in young adulthood or do they catch up? Findings from a Swedish birth cohort

BACKGROUND

Alcohol consumption among adolescents has declined considerably during the last two decades. However, it is unknown if these adolescents' alcohol consumption will remain low as they grow older. To our knowledge, this is one of the first studies that uses longitudinal data to examine if non-drinking adolescents have a lower alcohol consumption in young adulthood or if they catch up.

METHODS

A self-report survey was distributed to a birth cohort (n = 794) born in 1997 in a Swedish region when cohort members attended ninth grade (age 14-15 years) in 2012. Responders were divided into non-drinkers and alcohol users and assessed again in their late teens (17-18 years) and young adulthood (20-21 years).

RESULTS

In their late teens (17-18 years), non-drinkers at baseline consumed less alcohol and had a lower probability of harmful use compared with their alcohol-using peers. In young adulthood (20-21 years), these effects disappeared when adjustment was made for covariates. However, a stratified analysis showed that non-drinking adolescents low in conduct problems consumed less alcohol and had a lower probability of harmful use in young adulthood than alcohol-using peers.

CONCLUSIONS

This study suggests that the decline in alcohol use among adolescents in the past decades may be associated with a lower alcohol consumption in the late teens and young adulthood among those low in conduct problems. This may have promising implications for alcohol-related morbidity and mortality.

Clearing up the smoke: Physical and mental health considerations regarding cannabis use in adolescents with cystic fibrosis

The cannabis plant is the most used federally illegal drug in the United States and is widely used by adolescents. Cannabis has complex effects on the body and mind. All health professionals who take care of adolescents with cystic fibrosis (CF) should be aware of the factors impacting cannabis use in CF. Given limited evidence regarding the benefits of cannabis and the significant risks, clinicians have the responsibility to identify risk of cannabis use early, counsel patients about the risks, provide a safe space for ongoing conversations about cannabis use in the context of CF care, and deliver evidence-based interventions.

Enhancing axonal myelination in seniors: A review exploring the potential impact cannabis has on myelination in the aged brain

Consumption of cannabis is on the rise as public opinion trends toward acceptance and its consequent legalization. Specifically, the senior population is one of the demographics increasing their use of cannabis the fastest, but research aimed at understanding cannabis' impact on the aged brain is still scarce. Aging is characterized by many brain changes that slowly alter cognitive ability. One process that is greatly impacted during aging is axonal myelination. The slow degradation and loss of myelin (i.e., demyelination) in the brain with age has been shown to associate with cognitive decline and, furthermore, is a common characteristic of numerous neurological diseases experienced in aging. It is currently not known what causes this age-dependent degradation, but it is likely due to numerous confounding factors (i.e., heightened inflammation, reduced blood flow, cellular senescence) that impact the many cells responsible for maintaining overall homeostasis and myelin integrity. Importantly, animal studies using non-human primates and rodents have also revealed demyelination with age, providing a reliable model for researchers to try and understand the cellular mechanisms at play. In rodents, cannabis was recently shown to modulate the myelination process. Furthermore, studies looking at the direct modulatory impact cannabis has on microglia, astrocytes and oligodendrocyte lineage cells hint at potential mechanisms to prevent some of the more damaging activities performed by these cells that contribute to demyelination in aging. However, research focusing on how cannabis impacts myelination in the aged brain is lacking. Therefore, this review will explore the evidence thus far accumulated to show how cannabis impacts myelination and will extrapolate what this knowledge may mean for the aged brain.

Receptor protein tyrosine phosphatase β/ζ regulates loss of neurogenesis in the mouse hippocampus following adolescent acute ethanol exposure

Adolescence is a critical period for brain maturation in which this organ is more vulnerable to the damaging effects of ethanol. Administration of ethanol in mice induces a rapid cerebral upregulation of pleiotrophin (PTN), a cytokine that regulates the neuroinflammatory processes induced by different insults and the behavioral effects of ethanol. PTN binds Receptor Protein Tyrosine Phosphatase (RPTP) β/ζ and inhibits its phosphatase activity, suggesting that RPTPβ/ζ may be involved in the regulation of ethanol effects. To test this hypothesis, we have treated adolescent mice with the RPTPβ/ζ inhibitor MY10 (60 mg/kg) before an acute ethanol (6 g/kg) administration. Treatment with MY10 completely prevented the ethanol-induced neurogenic loss in the hippocampus of both male and female mice. In flow cytometry studies, ethanol tended to increase the number of NeuN+/activated Caspase-3+ cells particularly in female mice, but no significant effects were found. Ethanol increased Iba1+ cell area and the total marked area in the hippocampus of female mice, suggesting sex differences in ethanol-induced microgliosis. In addition, ethanol reduced the circulating levels of IL-6 and IL-10 in both sexes, although this reduction was only found significant in males and not affected by MY10 treatment. Interestingly, MY10 alone increased the total marked area and the number of Iba1+ cells only in the female hippocampus, but tended to reduce the circulating levels of TNF-α only in male mice. In summary, the data identify a novel modulatory role of RPTPβ/ζ on ethanol-induced loss of hippocampal neurogenesis, which seems unrelated to glial and inflammatory responses. The data also suggest sex differences in RPTPβ/ζ function that may be relevant to immune responses and ethanol-induced microglial responses.

Impact of Adolescent Cannabis Use on Neurocognitive and Brain Development

Research examining associations between frequent cannabis use in adolescence and brain-behavior outcomes has increased substantially over the past 2 decades. This review attempts to synthesize the state of evidence in this area of research while acknowledging challenges in interpretation. Although there is converging evidence that ongoing, frequent cannabis use in adolescence is associated with small reductions in cognitive functioning, there is still significant debate regarding the persistence of reductions after a period of abstinence. Similarly, there is controversy regarding the replicability of structural and functional neuroimaging findings related to frequent cannabis use in adolescence. Larger studies with informative designs are needed.

Impact of Cannabis Legalization on Adolescent Cannabis Use

Because of substantial limitations in available national data, such as inconsistencies among surveys and small sample sizes, the increased prevalence of cannabis use among adolescents since recreational legalization has not been directly observed. Nevertheless, both usage frequency and product potency have significantly increased, alongside alternative routes of delivery to smoking, such as vaping cannabis. Moreover, certain populations may be especially vulnerable to the effects of legalization. Regardless of differing state-level cannabis legalization status, the adverse consequences of cannabis on youth have clear negative impacts on mental health, medical symptoms, educational outcomes, and increased risk of addiction to other substances.

New Validated Short Questionnaire for the Evaluation of the Adherence of Mediterranean Diet and Nutritional Sustainability in All Adult Population Groups

High adherence to a Mediterranean diet (MD) is favourable for its sustainability and beneficial effects on health. The available questionnaires, according to the MD dietary pattern, include the assessment of moderate alcohol consumption; but some groups, such as young adults and pre-conceptional and pregnant women, are not allowed to consume it. The aim of this study was to validate a new short questionnaire (MedQ-Sus) excluding alcohol consumption, to measure the adherence to the MD and to evaluate the nutritional adherence to a sustainable diet. The Harvard validated questionnaire was used for the validation study. A total of 316 subjects (20 to 70 YOA) completed both questionnaires. A high Spearman correlation coefficient (rho = 0.69; p < 0.01) was found between the MedQ-Sus and Harvard scores; a statistically significant positive correlation was found for all eight food groups. The MedQ-Sus had a significant discriminative capacity between adherence and non-adherence to the MD (optimal cut-off point = 9.5, sensitivity 0.86, specificity = 0.65). A very high nutritional adherence to a sustainable diet was found in the subjects for olive oil (97%), dairy food (90%), fresh vegetables (89%), fish and fish products (73), fresh fruit (56%), and cereals and cereals products (42%). A very low adherence was found for legumes (22%) and meat and meat products (9%). The results showed MedQ-Sus is a valid and quick assessment instrument for the evaluation of the adherence to the MD in all population groups, and could also be useful to evaluate the nutritional sustainability of the diet.

Effects of SativexⓇ on cognitive function in patients with multiple sclerosis: A systematic review and meta-analysis

BACKGROUND

Cognitive impairment is a common manifestation of multiple sclerosis (MS).

OBJECTIVE

To assess by systematic review and meta-analysis available evidence regarding the impact of nabiximols oromucosal spray on cognition in patients with MS.

METHODS

A systematic literature search of clinical studies (all types, any comparator) that measured cognitive function in patients with MS spasticity treated with nabiximols. Meta-analysis for cognitive endpoints was not possible due to heterogenous measurement instruments and outcomes. Meta-analysis was performed for adverse events (AEs) of special interest (cognition disorders) reported in randomized controlled trials (RCTs) of nabiximols versus placebo in patients with MS (with or without spasticity). Certainty of evidence and risk of bias were assessed.

RESULTS

Seven clinical studies (three RCTs) directly assessing cognitive function were included in the qualitative analysis. There was no consistent evidence to suggest that nabiximols causes cognitive impairment as assessed by a range of specific psychometric instruments across cognitive domains. Thirteen double-blind, placebo-controlled RCTs (nabiximols, n = 964; placebo, n = 904) were included in the meta-analysis of cognitive AEs. Most cognitive AEs (30 of 32 events, 93.8%) reported with nabiximols in MS patients occurred with not in-label use, i.e., dosage >12 sprays per day and/or not administered primarily for treatment of spasticity.

CONCLUSIONS

Within the limitations of the review, we can conclude that no detrimental effects of nabiximols on cognitive function were observed in patients with MS spasticity during up to 12 months follow-up and that cognitive AEs were rare and occurred only when nabiximols was not used according to its approved label.

Shifting school health priorities pre-post cannabis legalization in Canada: Ontario secondary school rankings of student substance use as a health-related issue

This study examined how schools prioritize ten key health concerns among their student populations over time and whether schools' prioritization of alcohol and other drug use (AODU) corresponds to students' substance use behaviours and cannabis legalization as a major policy change. Data were collected from a sample of secondary schools in Ontario, Canada across four years (2015/16-2018/19 [N2015/16 = 65, N2016/17 = 68, N2017/18 = 61 and N2018/19 = 60]) as a part of the COMPASS study. School-level prevalence of cannabis and alcohol use between schools that did and did not prioritize student AODU as a health concern was examined. Ordinal mixed models examined whether student cannabis and alcohol use were associated with school prioritization of AODU. Chi-square tests examined changing health priorities among schools pre-post cannabis legalization. School priority ranking for AODU was mostly stable over time. While AODU was identified as an important health concern, most schools identified mental health as their first priority across the four years of the study. No significant changes to school AODU priorities were observed pre-post cannabis legalization nor was school prioritization of AODU associated with student cannabis and alcohol use behaviours. This study suggests that schools may benefit from guidance in identifying and addressing priority health concerns among their student population.

Detection of vaping, cannabis use, and hazardous prescription opioid use among adolescents

There has been a global surge in adolescents' use of electronic nicotine delivery systems (vaping), cannabis (vaped and edible), and prescription opioids, collectively termed ECPO. The nature of ECPO use can make it difficult to detect due to few obvious immediate physical and behavioural signs, as well as subtle long-term effects that allow adolescents to transition from initial exploration into hazardous ECPO use without easy detection by care providers. Here, we address the nature of the presentation of ECPO use in adolescents (roughly age 13-18 years), including challenges in detecting use and related complications, which affect screening, prevention, and intervention. We begin by reviewing empirical data on these difficult to detect effects in adolescents, including acute effects at cellular and neural levels and long-term neurocognitive and developmental changes that precede outwardly detectable physical signs. We then provide concrete approaches for providers to screen for ECPO use in adolescents even in the absence of overt physical and behavioural symptoms. Finally, we conclude with direct practice recommendations for prevention and intervention.

Sensation Seeking and Adolescent Drinking: Do Protective Behavioral Strategies Lower Risk?

Using a cross-sectional design, we examined protective behavioral strategies (PBS) as a moderator of the relationship between sensation seeking and hazardous drinking and alcohol-related consequences among high school seniors (N = 212). Hierarchical regression analyses indicated sensation seeking was a significant predictor of binge drinking (β = .65, p < .001), pre-partying (β = .71, p < .001), gaming (β = .75, p < .001), and alcohol-related consequences (β = .69, p < .001). Further, PBS moderated these relationships such that among high sensation seeking adolescents, PBS use was associated with better outcomes, including lower levels of binge drinking (β = -.37, p < .01), pre-partying (β = -.44, p < .01), gaming (β = -.31, p < .05), and alcohol-related consequences (β = -.53, p < .001). We discuss counseling implications, including assessment and harm reduction strategies focusing on PBS to reduce hazardous drinking among high sensation seeking adolescents.

Intersection between social inequality and emotion regulation on emerging adult cannabis use

Emerging adulthood (EA; ages 18-25) is characterized by socioemotional and neurodevelopmental challenges. Cannabis is a widely used substance among EAs, and hazardous use may increase risk for sustained use patterns and related health consequences. Research shows differential increases in hazardous use by objective as well as subjective measures of social inequality, with more concerning trajectories for youth with greater experiences of social inequality. Learning how to flexibly monitor and modify emotions in proactive ways (i.e., emotion regulation) is a central developmental task navigated during the EA window. Challenges to and with emotion regulation processes can contribute to the emergence of mental health symptoms during EA, including hazardous cannabis use. In this perspective, we highlight emotion dysregulation and social inequality as two critical factors that interact to either buffer against or exacerbate cannabis use during the EA period, noting critical gaps in the literature that merit additional research. We recommend novel methods and longitudinal designs to help clarify how dynamic cognition-emotion interplay predicts trajectories of negative emotional experiences and cannabis use in EA.

Prevalence of food addiction using the Yale-C scale in Mexican children with overweight and obesity

Background

The prevalence of excess weight and obesity in children has increased significantly worldwide. The concept of food addiction (FA) has been associated with eating-related problems and obesity. Studies on this topic have primarily examined adult samples and little is known about addictive-like eating among Mexican children and adolescents.

Methods

We conducted this study to examinate the prevalence of FA in a group of 291 overweight and obese children and adolescents using YFAS scale for children (YFAS-C) in Mexico.

Results

According to the YFAS-C approximately 14.4% of participants met for FA diagnosis. Forty-two (14.4%) received a FA diagnosis: 14 children and 28 adolescents. The number of FA symptoms in participants who received an FA diagnosis (M = 4.35, SD = 1.07) compared to participants with no FA diagnosis (M = 1.70, SD = 1.53) was significantly higher (p ≤ 0.001). There were no statistically significant gender differences and the proportion of subjects with an FA diagnosis did not differ by age between children and adolescents. FA is a focus of interest in attempting to explain certain behaviors that may contribute to the development of obesity and explain the failure of the weight loose programs in children.

Impact of recreational cannabis legalization on cannabis use, other substance use, and drug-related offending among justice-system-involved youth

The present study assessed whether cannabis use, other types of substance use, and drug-related offending changed among 1216 justice-system-involved youth after recreational cannabis legalization. Using generalized estimating equation population-averaged models, we compared youth in California, where recreational cannabis is legalized, and Pennsylvania, where recreational use is still prohibited. Results indicated that cannabis use, cannabis selling, and driving under the influences (DUIs) increased more among Pennsylvanian than Californian youth. We found no changes in alcohol or noncannabis drug use after legalization. Cigarette use did not change significantly among Pennsylvanian youth, but Californian youth exhibited decreased cigarette use after legalization. Although not directly tested in the present analysis, it is possible that changes in state-level recreational cannabis policies throughout the U.S. may contribute to more permissive attitudes toward cannabis, which leads to higher use and use-related outcomes. Future research should continue to consider the potential impacts of legalization on other types of risky and illegal behavior.

Problematic alcohol use in Austrian apprentices during the COVID-19 pandemic

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Problematic alcohol use was twice as likely in apprentices with depressive and anxiety symptoms.

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Problematic alcohol use was more prevalent in apprentices over 18.

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Problematic alcohol use was not related to gender, migration background or lockdown.

This study assessed problematic alcohol use in Austrian apprentices during the COVID-19 pandemic. An online survey was performed via REDCap with a sample of 1442 apprentices (53.3% female, 45.4% male, 1.1% non-binary, 28.4% migration background) from 29th March to 18th May 2021. The CAGE questionnaire was used to measure problematic alcohol use. Chi-square tests revealed that problematic alcohol use was more likely in apprentices with depressive symptoms (OR: 2.1), anxiety (OR: 2.1) or insomnia (OR: 1.4) and those over 18 (OR: 1.6). There were no differences in problematic alcohol use according to gender, migration background, or lockdown status.

Elevated striatal glutamate + glutamine in recreational cannabis users during abstinence

Cannabis withdrawal symptoms contribute to relapse, but the underlying mechanism remains unclear. We hypothesize that cannabis withdrawal may be associated with a reset of regional γ-amino butyric acid (GABA) and glutamate concentrations secondary to changes in the endocannabinoid system during abstinence and conducted a study on this issue. We used magnetic resonance spectroscopy (MRS) to detect the associated changes of these neurochemicals in twenty-six frequent, recreational cannabis users and eleven age-matched non-using controls. Twenty users (8F/12M) and ten control (5F/5M) participants completed a verified 21-day abstinence period. Striatal GABA and glutamine concentrations were measured at baseline and on abstinence days 7 and 21 in conjunction with measures of cannabis withdrawal symptoms and mood state. Cannabis users reported increased self-reported ratings of cannabis-withdrawal-symptoms on abstinence day 7 relative to controls. Striatal glutamate + glutamine (Glx) group concentrations were elevated in cannabis users at baseline and abstinence days 7 and 21 (F = 7.16, p = 0.012), and changes in GABA concentration and withdrawal symptoms between baseline and abstinence day 7 were positively correlated (r = 0.550, p = 0.010). In addition, baseline striatal GABA concentrations were negatively correlated with withdrawal symptoms on abstinence day 7 (r = -0.680, p = 0.003). Our data demonstrate that striatal Glx was elevated in cannabis users and baseline striatal GABA correlated with withdrawal during the abstinence. In addition, striatal GABA may temporally correlate with self-reported withdrawal symptoms during the initial days of abrupt cannabis abstinence. These findings provide preliminary evidence that striatal GABA and Glx are associated with the severity of cannabis withdrawal.

Patterns of Cannabis Use among Canadian Youth over Time; Examining Changes in Mode and Frequency Using Latent Transition Analysis

Background: Historically substance use literature has focused on smoking as the main mode of cannabis consumption, so there are knowledge gaps surrounding current understanding of edibles and vaping. These alternative modes of cannabis use are already common among Canadian youth; however, little is known about how these cannabis use patterns change over time. Methods: This study examined the mode (smoking, eating/drinking, vaping) and frequency of cannabis use among a large sample of Canadian youth who participated in 2017-2018 and 2018-2019 data collection waves of the COMPASS study. Using latent transition analysis, this sample consisting of 18,824 youth in grades 9-12 were categorized into cannabis use classes stratified by sex, and their transition between these classes over the one-year period was examined. Results: Three cannabis use classes were identified (occasional multimode, regular multimode, and smoking) alongside one nonuse class. Among youth who reported cannabis use at baseline, transitioning to a multimode group, and/or increasing frequency of multimode use was likely over the one-year period. Conclusions: These findings may highlight a key leverage point for harm-reduction strategies which aim to prevent cannabis related harms associated with high frequency use.

Multiple health risk behaviors and mental health from a life course perspective: The Dutch TRAILS study

We examined trajectories of multiple health risk behavior (MHRB) patterns throughout adolescence, and changes in mental health from childhood to young adulthood. Further, we assessed how continuity or onset of MHRBs overall were associated with subsequent changes in mental health, and whether this varied by type of MHRBs. We used six waves of the prospective Dutch TRAILS study (2001-2016; n = 2229), covering ages 11 until 23. We measured MHRBs (substance use: alcohol misuse, cannabis use, smoking; and obesity-related: overweight, physical inactivity, irregular breakfast intake) at three time points during adolescence. We assessed mental health as Youth/Adult Self-report total problems at ages 11 and 23. Latent class growth analyses and ANOVA were used to examine longitudinal trajectories and associations. We identified six developmental trajectories for the total of MHRBs and mental health. Trajectories varied regarding likelihood of MHRBs throughout adolescence, mental health at baseline, and changes in mental health problems in young adulthood. We found no associations for the continuity of overall MHRBs throughout adolescence, and neither for early, mid- or late onset, with changes in mental health problems in young adulthood. However, continuity of MHRBs in the obesity-related subgroup was significantly associated with an increase in mental health problems. Adolescents with the same MHRB patterns may, when reaching adulthood, have different levels of mental health problems, with mental health at age 11 being an important predictor. Further, involvement with obesity-related MHRBs continuously throughout adolescence is associated with increased mental health problems in young adulthood.

The Effects of Alcohol and Cannabis Co-Use on Neurocognitive Function, Brain Structure, and Brain Function

Purpose of review

Given increases in the rates of alcohol and cannabis co-use among adolescents and young adults, this review aims to summarize literature on the effects of alcohol and cannabis co-use on neurocognitive functioning, brain structure, and brain function.

Recent findings

The limited existing studies examining concurrent, recent, and lifetime alcohol and cannabis co-use suggest effects on the brain are likely multifaceted. The majority of studies report that co-use is associated with negative outcomes such as impaired cognitive function and significant alterations in key structural and functional regions of the brain, while others report null effects of co-use compared to non-substance using control and single-substance use groups.

Summary

Current studies lack a general consensus on methodology, definitions of concurrent and simultaneous use, and neuroimaging approaches, which makes it challenging to draw strong conclusions about the effects of co-use. More studies are needed to explore the effects of co-use in the context of simultaneous alcohol and cannabis use.

Wonder or evil?: Multifaceted health hazards and health benefits of Cannabis sativa and its phytochemicals

Cannabis sativa, widely known as 'Marijuana' poses a dilemma for being a blend of both good and bad medicinal effects. The historical use of Cannabis for both medicinal and recreational purposes suggests it to be a friendly plant. However, whether the misuse of Cannabis and the cannabinoids derived from it can hamper normal body physiology is a focus of ongoing research. On the one hand, there is enough evidence to suggest that misuse of marijuana can cause deleterious effects on various organs like the lungs, immune system, cardiovascular system, etc. and also influence fertility and cause teratogenic effects. However, on the other hand, marijuana has been found to offer a magical cure for anorexia, chronic pain, muscle spasticity, nausea, and disturbed sleep. Indeed, most recently, the United Nations has given its verdict in favour of Cannabis declaring it as a non-dangerous narcotic. This review provides insights into the various health effects of Cannabis and its specialized metabolites and indicates how wise steps can be taken to promote good use and prevent misuse of the metabolites derived from this plant.

Cannabinoids for the treatment of cannabis use disorder: New avenues for reaching and helping youth?

Cannabis use peaks during adolescence and emerging adulthood, and cannabis use disorder (CUD) is associated with a wide range of adverse outcomes. This is particularly pertinent in youth, because the developing brain may be more vulnerable to adverse effects of frequent cannabis use. Combining evidence-based psychosocial interventions with safe and effective pharmacotherapy is a potential avenue to improve youth outcomes, but we lack approved CUD pharmacotherapies. Here, we review new potential avenues for helping youth with CUD, with a particular focus on cannabinoid-based treatments. Evidence from placebo-controlled RCTs suggests synthetic delta-9-tetrahydrocannabinol (THC) decreases withdrawal symptoms, but not cannabis use, in adults with daily cannabis use/CUD, while findings regarding formulations containing THC combined with cannabidiol (CBD) are mixed. Preliminary evidence from two placebo-controlled RCTs in adults with CUD suggests that both Fatty Acid Amide Hydrolase inhibitors and CBD can reduce cannabis use. However, larger trials are needed to strengthen the evidence. Findings from adults point to cannabinoid-based treatments as a potential strategy that should be examined in youth with CUD.

Untangling the Complexities of Substance Use Initiation and Recovery: Client Reflections on Opioid Use Prevention and Recovery From a Social-Ecological Perspective

Background:

In Canada, the rate of opioid use, opioid use disorder (OUD), and associated mortality and morbidity are higher among Indigenous Peoples than the general population. Indigenous Peoples on medications for opioid use disorders (MOUD) often face distinct barriers that hinder their clinical progress, leading to treatment attrition.

Methods:

We used a social-ecological model to inquire into clients’ experiences with a history of treatment failure for OUD. We used exploratory qualitative research to engage 22 clients with a history of OUD treatment dropouts and who are currently on MOUD. In-depth, semi-structured interviews lasting an average of 30 minutes were conducted on-site.

Results:

We identified 4 themes from the study: (a) risk for substance use; (b) factors sustaining substance use; (c) factors leading to treatment, and (d) treatment failure and re-enrollment.

Conclusion:

Using a socio-ecological model helps to understand factors that influence an individual’s risk for OUD, decision to pursue treatment, and treatment outcomes. Furthermore, social ecological model also creates possibilities to develop supportive, multilevel interventions to prevent OUD risks and support for clients on MOUD. Such interventions include mitigating adverse childhood experiences, supporting families, and creating safe community environments.

Rapamycin prevents the long-term impairing effects of adolescence Δ-9-tetrahydrocannabinol on memory and plasticity in male rats

Long-lasting cognitive impairment is one of the most central negative consequences related to the exposure to cannabis during adolescence and particularly of Δ-9-tetrahydrocannabinol (THC). The aim of this study was to compare the protracted effects of adolescent versus late-adolescent chronic exposure to THC on short-term memory and plasticity and to examine whether rapamycin, a blocker of the mammalian target of rapamycin (mTOR) pathway, can restore THC-induced deficits in memory and plasticity. Male rats were injected with ascending doses of THC [2.5, 5, 10 mg/kg; intraperitoneally (i.p.)] during adolescence and late-adolescence (post-natal days 30-41 and 45-56, respectively), followed by daily injections of rapamycin (1 mg/kg, i.p.) during the first 10 days of cessation from THC. Thirty days after the last injection, rats were tested for short-term and working memory, anxiety-like behaviour, and plasticity in the pathways projecting from the ventral subiculum (vSub) of the hippocampus to the prefrontal cortex (PFC) and nucleus accumbens (NAc). THC exposure in adolescence, but not late-adolescence, was found to induce long-term deficits in object recognition short-term memory and synaptic plasticity in the hippocampal-accumbens pathway. Importantly, rapamycin rescued these persistent effects of THC administered during adolescence. Our findings show that some forms of memory and plasticity are sensitive to chronic THC administration during adolescence and that rapamycin administered during THC cessation may restore cognitive function and plasticity, thus potentially protecting against the possible long-term harmful effects of THC.

Neuropsychological and neurophysiological predictors and consequences of cannabis and illicit substance use during neurodevelopment: a systematic review of longitudinal studies

Adolescence and early adulthood are crucial periods of neurodevelopment characterised by functional, structural, and cognitive maturation, which helps prepare young people for adulthood. This systematic review of longitudinal studies aims to delineate neural predictors from neural consequences of cannabis and illicit substance use, as well as investigate the potential for the developing brain (at ages 10-25 years) to recover after damage. Five databases were searched to yield a total of 38 eligible studies, with some assessing multiple outcome techniques, including 22 neuroimaging, two neurophysiological, and 22 neuropsychological findings. High-quality evidence suggested that delayed or irregular neurodevelopment in executive functioning, particularly emotional perception, might predispose young people to higher frequency substance use. There was evidence of functional, structural, and cognitive deficits proceeding substance use, with harm potentially dependent on the frequency of use and recovery potentially dependent on the duration of use. Identifying aberrant neurodevelopment in young people is crucial for preventing substance use-related harm.

Alcohol and Brain Development in Adolescents and Young Adults: A Systematic Review of the Literature and Advisory Report of the Health Council of the Netherlands

Young people, whose brains are still developing, might entail a greater vulnerability to the effects of alcohol consumption on brain function and development. A committee of experts of the Health Council of the Netherlands evaluated the state of scientific knowledge regarding the question whether alcohol negatively influences brain development in young people. A systematic literature search for prospective studies was performed in PubMed and PsychINFO, for longitudinal studies of adolescents or young adults ranging between 12 and 24 y of age at baseline, investigating the relation between alcohol use and outcome measures of brain structure and activity, cognitive functioning, educational achievement, or alcohol use disorder (AUD), with measures at baseline and follow-up of the outcome of interest. Data were extracted from original articles and study quality was assessed using the Newcastle-Ottawa Scale. A total of 77 studies were included, 31 of which were of sufficient quality in relation to the study objectives. There were indications that the gray matter of the brain develops abnormally in young people who drink alcohol. In addition, the more often young people drink or the younger they start, the higher the risk of developing AUD later in life. The evidence on white matter volume or quality, brain activity, cognitive function, and educational achievement is still limited or unclear. The committee found indications that alcohol consumption can have a negative effect on brain development in adolescents and young adults and entails a risk of later AUD. The committee therefore considers it a wise choice for adolescents and young adults not to drink alcohol.

An Observational, Longitudinal Study of Cognition in Medical Cannabis Patients over the Course of 12 Months of Treatment: Preliminary Results

OBJECTIVE

Cannabis use has increased dramatically across the country; however, few studies have assessed the long-term impact of medical cannabis (MC) use on cognition. Studies examining recreational cannabis users generally report cognitive decrements, particularly in those with adolescent onset. As MC patients differ from recreational consumers in motives for use, product selection, and age of onset, we assessed cognitive and clinical measures in well-characterized MC patients over 1 year. Based on previous findings, we hypothesized MC patients would not show decrements and might instead demonstrate improvements in executive function over time.

METHOD

As part of an ongoing study, MC patients completed a baseline visit prior to initiating MC and evaluations following 3, 6, and 12 months of treatment. At each visit, patients completed a neurocognitive battery assessing executive function, verbal learning/memory, and clinical scales assessing mood, anxiety, and sleep. Exposure to delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) was also quantified.

RESULTS

Relative to baseline, MC patients demonstrated significant improvements on measures of executive function and clinical state over the course of 12 months; verbal learning/memory performance generally remained stable. Improved cognitive performance was not correlated with MC use; however, clinical improvement was associated with higher CBD use. Analyses suggest cognitive improvements were associated with clinical improvement.

CONCLUSIONS

Study results extend previous pilot findings, indicating that MC patients may exhibit enhanced rather than impaired executive function over time. Future studies should examine distinctions between recreational and MC use to identify potential mechanisms related to cognitive changes and the role of clinical improvement.

Cannabis Use and Brain Volume in Adolescent and Young Adult Cannabis Users: Effects Moderated by Sex and Aerobic Fitness

OBJECTIVES

Studies examining the impact of adolescent and young adult cannabis use on structural outcomes have been heterogeneous. One already-identified moderator is sex, while a novel potential moderator is extent of aerobic fitness. Here, we sought to investigate the associations of cannabis use, sex, and aerobic fitness levels on brain volume. Second, we explored brain-behavior relationships to interpret these findings.

METHODS

Seventy-four adolescents and young adults (36 cannabis users and 38 controls) underwent 3 weeks of monitored cannabis abstinence, aerobic fitness testing, structural neuroimaging, and neuropsychological testing. Linear regressions examined cannabis use and its interaction with sex and aerobic fitness on whole-brain cortical volume and subcortical regions of interests.

RESULTS

No main-effect differences between cannabis users and nonusers were observed; however, cannabis-by-sex interactions identified differences in frontal, temporal, and paracentral volumes. Female cannabis users generally exhibited greater volume while male users exhibited less volume compared to same-sex controls. Positive associations between aerobic fitness and frontal, parietal, cerebellum, and caudate volumes were observed. Cannabis-by-fitness interaction was linked with left superior temporal volume. Preliminary brain-behavior correlations revealed that abnormal volumes were not advantageous in either male or female cannabis users.

CONCLUSIONS

Aerobic fitness was linked with greater brain volume and sex moderated the effect of cannabis use on volume; preliminary brain-behavior correlations revealed that differences in cannabis users were not linked with advantageous cognitive performance. Implications of sex-specific subtleties and mechanisms of aerobic fitness require large-scale investigation. Furthermore, present findings and prior literature on aerobic exercise warrant examinations of aerobic fitness interventions that aimed at improving neurocognitive health in substance-using youth.

Resting state functional connectivity in the default mode network: Relationships between cannabis use, gender, and cognition in adolescents and young adults

INTRODUCTION

Cannabis is the most commonly used illicit substance in the United States, and nearly 1 in 4 young adults are current cannabis users. Chronic cannabis use is associated with changes in resting state functional connectivity (RSFC) in the default mode network (DMN) in adolescents and young adults; results are somewhat inconsistent across studies, potentially due to methodological differences. The aims of the present study were to examine potential differences in DMN RSFC between cannabis users and controls, and to examine, as an exploratory analysis, if gender moderated any findings. We further examined whether differences in RSFC related to differences in performance on selected neuropsychological measures.

MATERIALS AND METHODS

Seventy-seven 16-26-year-old participants underwent an MRI scan (including resting state scan), neuropsychological battery, toxicology screening, and drug use interview. Differences in DMN connectivity were examined between groups (cannabis vs. control) and with an exploratory group by gender interaction, using a left posterior cingulate cortex (PCC) seed-based analysis conducted in AFNI.

RESULTS

Cannabis users demonstrated weaker connectivity than controls between the left PCC and various DMN nodes, and the right Rolandic operculum/Heschl's gyrus. Cannabis users demonstrated stronger connectivity between the left PCC and the cerebellum and left supramarginal gyrus. The group by gender interaction was not significantly associated with connectivity differences. Stronger left PCC-cerebellum connectivity was associated with poorer performance on cognitive measures in cannabis users. In controls, intra-DMN connectivity was positively correlated with performance on a speeded selective/sustained attention measure.

DISCUSSION

Consistent with our hypotheses and other studies, cannabis users demonstrated weaker connectivity between the left PCC and DMN nodes. Chronic THC exposure may alter GABA and glutamate concentrations, which may alter brain communication. Future studies should be conducted with a larger sample size and examine gender differences and the mechanism by which these differences may arise.

Disentangling the lasting effects of adolescent cannabinoid exposure

Cannabis is the most widely used illicit substance among adolescents, and adolescent cannabis use is associated with various neurocognitive deficits that can extend into adulthood. A growing body of evidence supports the hypothesis that adolescence encompasses a vulnerable period of development where exposure to exogenous cannabinoids can alter the normative trajectory of brain maturation. In this review, we present an overview of studies of human and rodent models that examine lasting effects of adolescent exposure. We include evidence from meta-analyses, longitudinal, or cross-sectional studies in humans that consider age of onset as a factor that contributes to the behavioral dysregulation and altered structural or functional development in cannabis users. We also discuss evidence from preclinical rodent models utilizing well-characterized or innovative routes of exposure, investigating the effects of dose and timing to produce behavioral deficits or alterations on a neuronal and behavioral level. Multiple studies from both humans and animals provide contrasting results regarding the magnitude of residual effects. Combined evidence suggests that exposure to psychoactive cannabinoids during adolescence has the potential to produce subtle, but lasting, alterations in neurobiology and behavior.

Are non-abstinent reductions in World Health Organization drinking risk level a valid treatment target for alcohol use disorders in adolescents with ADHD?

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Changes in WHO alcohol risk level are highly variable in youth treated for ADHD/SUD.

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Achieving > 2-level reduction in WHO risk is linked to improvements in functioning.

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Achieving > 2-level reduction in WHO risk is linked to decreased ADHD symptoms.

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> 2-level reduction in WHO risk may be a valid non-abstinent AUD outcome in youth with ADHD/SUD.

Introduction

Abstinence from drinking represents the primary treatment target for alcohol use disorders (AUD) in youth, but few adolescents who engage in problematic drinking seek treatment. A reduction in World Health Organization (WHO) drinking risk level has been established as valid and reliable non-abstinent treatment target for AUD in adults but remains unstudied in youth.

Methods

The present study used data from the NIDA-CTN-0028 trial to examine associations between reductions in WHO drinking risk level and changes in global functioning and attention-deficit hyperactivity disorder (ADHD) symptoms during treatment in a sample of adolescents (ages 13–18 years) with ADHD and comorbid substance use disorder (SUD) (n = 297, 61% with AUD) receiving a 16-week intervention that combined ADHD pharmacotherapy (OROS-methylphenidate vs. placebo) and drug-focused cognitive-behavioral therapy.

Results

Shifts in drinking risk level during treatment were highly variable in adolescents treated for ADHD/SUD, and influenced by AUD diagnostic status. In the total sample, 15% of participants had a 2-level or greater reduction in WHO drinking risk level, with 59% and 24% showing no change or an increase in risk-level during treatment respectively. Achieving at least a 2-level change in WHO drinking risk level during treatment was associated with greater reduction in ADHD symptoms and better functional outcomes.

Conclusions

These findings parallel the adult AUD literature and provide preliminary support for the use 2-level reductions in WHO risk levels for alcohol use as a clinically valid non-abstinent treatment outcome for youth with ADHD and comorbid AUD.

Neural and behavioral correlates associated with adolescent marijuana use

Purpose of Review

Marijuana (MJ) is one of the most commonly used drugs among adolescents. Exposure to MJ during adolescence can lead to alterations in brain development, and, subsequently to the behavioral correlates regulated by the affected brain regions. In this review, we discuss findings from preclinical and human studies examining the relationship between adolescent MJ use and the neurobiological and behavioral correlates associated with it.

Recent Findings

Current findings indicate that adolescent MJ use is associated with alterations in brain structure and function, especially in regions that express high levels of the cannabinoid 1 receptor such as the prefrontal cortex, hippocampus, cerebellum and limbic regions. These alterations are correlated with changes in affective, cognitive and reward-seeking behavior. Furthermore, evidence suggests that exposure to MJ during adolescence can have long-lasting and pronounced neural and behavioral effects into adulthood.

Summary

The wide ranging neural and behavioral correlates associated with MJ use during adolescence highlight the need for further studies to better understand the potential risk factors and/or neurotoxic effects of adolescent MJ use.