The CannTeen study: verbal episodic memory, spatial working memory, and response inhibition in adolescent and adult cannabis users and age-matched controls

Cannabis use and neurocognitive performance at 13-14 Years-Old: Optimizing assessment with hair toxicology in the Adolescent brain cognitive development (ABCD) study

OBJECTIVE

Cannabis is widely used, including in early adolescence, with prevalence rates varying by measurement method (e.g., toxicology vs. self-report). Critical neurocognitive development occurs throughout adolescence. Given conflicting prior brain-behavior results in cannabis research, improved measurement of cannabis use in younger adolescents is needed.

METHODS

Data from the Adolescent Brain Cognitive Development (ABCD) Study Year 4 follow-up (participant age: 13-14 years-old) included hair samples assessed by LC-MS/MS and GC-MS/MS, quantifying THCCOOH (THC metabolite), THC, and cannabidiol concentrations, and the NIH Toolbox Cognitive Battery. Youth whose hair was positive for cannabinoids or reported past-year cannabis use were included in a Cannabis Use (CU) group (n = 123) and matched with non-using Controls on sociodemographics (n = 123). Standard and nested ANCOVAs assessed group status predicting cognitive performance, controlling for family relationships. Follow-up correlations assessed cannabinoid hair concentration, self-reported cannabis use, and neurocognition.

RESULTS

CU scored lower on Picture Memory (p = .03) than Controls. Within the CU group, THCCOOH negatively correlated with Picture Vocabulary (r = -0.20, p = .03) and Flanker Inhibitory Control and Attention (r = -0.19, p = .04), and past-year cannabis use was negatively associated with List Sorting Working Memory (r = -0.33, p = .0002) and Picture Sequence Memory (r = -0.19, p = .04) performances.

CONCLUSIONS

Youth who had used cannabis showed lower scores on an episodic memory task, and more cannabis use was linked to poorer performances on verbal, inhibitory, working memory, and episodic memory tasks. Combining hair toxicology with self-report revealed more brain-behavior relationships than self-report data alone. These youth will be followed to determine long-term substance use and neurocognition trajectories.

Should gastroenterologists prescribe cannabis? The highs, the lows and the unknowns

Cannabis, commonly known as marijuana, is a drug extracted from the Cannabis plant known for its psychotropic and medicinal properties. It has been used for healing purposes during ancient times, although its psychoactive components led to its restricted use in medicine. Nonetheless, cannabis is found to have modulatory effects on the endocannabinoid system exhibiting its medicinal role in the gastrointestinal (GI) system. Emerging animal and human studies demonstrate the influential effects of cannabis on a variety of GI diseases including inflammatory bowel disease, motility disorders and GI malignancies. It also has a regulatory role in GI symptoms including nausea and vomiting, anorexia, weight gain, abdominal pain, among others. However, both its acute and chronic use can lead to undesirable side effects such as dependency and addiction, cognitive impairment and cannabinoid hyperemesis syndrome. We will discuss the role of cannabis in the GI system as well as dosing strategies to help guide gastroenterologists to assess its efficacy and provide patient counseling before prescription of medical marijuana.

Impulsivity and Risk-Taking Behavior in School-Going Adolescents

Introduction Impulsivity (or impulsiveness) and risk-taking behavior are significant concerns as the adolescent population is at a higher risk of injuries and violence, unhealthy sexual behaviors, and drug- and alcohol-related problems. The early identification of these traits in adolescents can prove beneficial through timely interventions. This study was conducted to assess impulsive behavior and risk-taking behavior among school-going adolescents in New Delhi, India, and to study the association, if any, between the two. Methodology A cross-sectional study was conducted among 571 students of classes 9th-10th in three randomly selected schools in a part of Delhi, India. Barratt Impulsiveness Scale - Brief (BIS-Brief) was used to evaluate impulsivity, and risk-taking behavior was assessed using the RT-18 tool. Results The majority (72.3%) of the 571 students were aged 14-15 years. Among the students, 56.0% were males. The impulsivity score obtained ranged from 8 to 30, with a mean score of 15.7 (SD ±4.1). The risk-taking score ranged from 2 to 18, with a mean score of 9.9 (SD ±2.9). Impulsivity was seen to be significantly higher among the female students (p=0.004). The risk-taking behavior was significantly higher among the students from government schools, among the females, and among those who used the internet more. There was a significant direct association between impulsivity and risk-taking behavior among the students (correlation coefficient 0.301, p<0.001). Conclusion The study results showed that the mean impulsivity and risk-taking scores were comparable to other studies in adolescent age groups done internationally using the same tools. Impulsivity and risk-taking behavior were both found to be higher among females. There was a significant direct association between impulsivity and risk-taking.

Anhedonia, Apathy, Pleasure, and Effort-Based Decision-Making in Adult and Adolescent Cannabis Users and Controls

BACKGROUND

Cannabis use may be linked with anhedonia and apathy. However, previous studies have shown mixed results, and few have examined the association between cannabis use and specific reward sub-processes. Adolescents may be more vulnerable than adults to harmful effects of cannabis. This study investigated (1) the association between non-acute cannabis use and apathy, anhedonia, pleasure, and effort-based decision-making for reward; and (2) whether these relationships were moderated by age group.

METHODS

We used data from the "CannTeen" study. Participants were 274 adult (26-29 years) and adolescent (16-17 years) cannabis users (1-7 d/wk use in the past 3 months) and gender- and age-matched controls. Anhedonia was measured with the Snaith-Hamilton Pleasure Scale (n = 274), and apathy was measured with the Apathy Evaluation Scale (n = 215). Effort-based decision-making for reward was measured with the Physical Effort task (n = 139), and subjective wanting and liking of rewards was measured with the novel Real Reward Pleasure task (n = 137).

RESULTS

Controls had higher levels of anhedonia than cannabis users (F1,258 = 5.35, P = .02, η p2 = .02). There were no other significant effects of user-group and no significant user-group*age-group interactions. Null findings were supported by post hoc Bayesian analyses.

CONCLUSION

Our results suggest that cannabis use at a frequency of 3 to 4 d/wk is not associated with apathy, effort-based decision-making for reward, reward wanting, or reward liking in adults or adolescents. Cannabis users had lower anhedonia than controls, albeit at a small effect size. These findings are not consistent with the hypothesis that non-acute cannabis use is associated with amotivation.