The CannTeen Study: Cannabis use disorder, depression, anxiety, and psychotic-like symptoms in adolescent and adult cannabis users and age-matched controls

Abstract

Background: Adolescence is characterised by psychological and neural development. Cannabis harms may be accentuated during adolescence. We hypothesised that adolescents would be more vulnerable to the associations between cannabis use and mental health and addiction problems than adults. Method: As part of the ‘CannTeen’ study, we conducted a cross-sectional analysis. There were 274 participants: split into groups of adolescent users ( n = 76; 16–17 years old) and controls ( n = 63), and adult users ( n = 71; 26–29 years old) and controls ( n = 64). Among users, cannabis use frequency ranged from 1 to 7 days/week, while controls had 0–10 lifetime exposures to cannabis. Adolescent and adult cannabis users were matched on cannabis use frequency (mean=4 days/week). We measured Diagnostic and Statistical Manual (DSM-5) Cannabis Use Disorder (CUD), Beck Depression Inventory, Beck Anxiety Inventory and Psychotomimetic States Inventory-adapted. Results: After adjustment for covariates, adolescent users were more likely to have severe CUD than adult users (odd ratio = 3.474, 95% confidence interval (CI) = 1.501–8.036). Users reported greater psychotic-like symptoms than controls ( b = 6.004, 95% CI = 1.211–10.796) and adolescents reported greater psychotic-like symptoms than adults ( b = 5.509, 95% CI = 1.070–9.947). User-group was not associated with depression or anxiety. No significant interactions between age-group and user-group were identified. Exploratory analyses suggested that cannabis users with severe CUD had greater depression and anxiety levels than cannabis users without severe CUD. Conclusion: Adolescent cannabis users are more likely than adult cannabis users to have severe CUD. Adolescent cannabis users have greater psychotic-like symptoms than adult cannabis users and adolescent controls, through an additive effect. There was no evidence of an amplified vulnerability to cannabis-related increases in subclinical depression, anxiety or psychotic-like symptoms in adolescence. However, poorer mental health was associated with the presence of severe CUD.

Age differences in the behavioural economics of cannabis use: Do adolescents and adults differ on demand for cannabis and discounting of future reward?

“…Interestingly, a separate analysis of cross-sectional 'CannTeen' data has found AdolescentsWUC to have greater odds of having severe CUD than AdultsWUC, measured by DSM-5 symptoms (Lawn et al, 2022). Our findings of age-differences in cannabis demand suggest that adolescents may be in a riskier category who are less sensitive to price and have greater cannabis consumption when it is free.…”

“…This is an analysis of cross-sectional data from the baseline session of the longitudinal CannTeen study (Lawn et al, 2022). The study protocol describes aims, participants, power analysis, data collection procedures, tasks and timelines (Lawn et al, 2020).…”

Associations between regular cannabis use and brain resting-state functional connectivity in adolescents and adults

“…Readers are directed to the full study protocol (Lawn et al, 2019) for further specification of aims, data collection procedures, tasks, and power calculations for the full project. Other recent manuscripts report the full study and have focussed on cognitive effects and clinical symptoms in this cohort (Will Lawn et al, 2022; W Lawn et al, 2022). Participants attended five behavioural sessions, one every three months, over the course of one year.…”

Cannabinoids: From the brain to society

“…Lawn et al (2022) reported findings from the CannTeen Study, particularly cannabis use disorder, depression, anxiety and psychotic-like symptoms in adolescent and adult cannabis users and age-matched controls. Harms from cannabis may be greater in adolescence due to effects on psychological and brain development.…”

“…No dose of cannabidiol examined induced feelings of intoxication or impaired cognition and interestingly the plasma measures of can nabidiol persisted longer than expected. Lawn et al (2022) reported findings from the CannTeen Study, particularly cannabis use disorder, depression, anxiety and psychoticlike symptoms in adolescent and adult cannabis users and agematched controls. Harms from cannabis may be greater in adolescence due to effects on psychological and brain develop ment.…”