Clinical Takeaway
Adolescents with depression and anxiety symptoms showed increased likelihood of initiating and using cannabis more frequently over an 18-month follow-up period. This research supports the self-medication hypothesis, where young people may turn to cannabis to cope with emotional distress. Clinicians should screen for internalizing symptoms early, as these may serve as modifiable risk factors for adolescent cannabis use.
#15 Anxiety, depression and risk of cannabis use: Examining the internalising pathway to use among Chilean adolescents.
Citation: Stapinski Lexine A et al.. Anxiety, depression and risk of cannabis use: Examining the internalising pathway to use among Chilean adolescents.. Drug and alcohol dependence. 2016. PMID: 27427415.
Design: 5 Journal: 0 N: 4 Recency: 0 Pop: 3 Human: 1 Risk: -2
- Preclinical only
Abstract: BACKGROUND: Adolescents who experience internalising symptoms may be susceptible to the use of alcohol and other substances in an attempt to alleviate or cope with these symptoms. We examined the hypothesised internalising pathway from symptoms of depression, generalised anxiety, social anxiety and panic, to incidence and frequency of cannabis use 18 months later. METHOD: Longitudinal cohort study of participants (n=2508; 45% female; mean age 14.5 years) recruited from the 9th grade at 22 low-income secondary schools in Santiago, Chile. Baseline internalising symptoms were assessed using the Beck Depression Inventory and the Revised Child Anxiety and Depression Scale. Frequency of cannabis was assessed at baseline, 6 month and 18 month follow-up. RESULTS: High rates of use were observed in this sample, with 40.3% reporting cannabis use at least once over the study period. Adjusted for baseline cannabis use, symptoms of depression, panic and generalised anxiety were associated with greater cannabis use frequency 18 months later. When all predictors were considered simultaneously, only generalised anxiety symptoms showed an independent association with subsequent cannabis use frequency (OR: 1.23, 95% CI: 1.08-1.41). Generalised anxiety symptoms were also associated with a 25% increased risk of transitioning from non-user to use of cannabis during the study (OR: 1.25, 95% CI: 1.09-1.44). CONCLUSIONS: Internalising symptoms, and in particular symptoms of generalised anxiety, increase risk of cannabis use during adolescence. Targeted interventions that promote adaptive anxiety management among high-risk adolescents may represent a promising strategy to prevent uptake of cannabis use during adolescence.
What This Study Teaches Us
Among Chilean adolescents, generalised anxiety symptoms independently predicted increased cannabis use frequency and a 25% higher risk of transitioning to cannabis use over 18 months. Depression and panic symptoms showed initial associations but lost statistical significance when anxiety was considered alongside other internalising symptoms.
Why This Matters Clinically
Clinicians screening adolescents for substance use risk should pay particular attention to generalised anxiety, not just mood disorders. For patients and families, this highlights that untreated anxiety in teens may drive cannabis initiation, making anxiety management a potential prevention strategy worth discussing.
Study Snapshot
| Study Design | Prospective longitudinal cohort study with baseline, 6-month, and 18-month follow-up assessments |
| Population | 2,508 Chilean adolescents (45% female, mean age 14.5 years) recruited from 9th grade at 22 low-income schools in Santiago |
| Intervention | None; observational study. Internalising symptoms (depression, anxiety subtypes) measured at baseline using Beck Depression Inventory and Revised Child Anxiety and Depression Scale |
| Primary Outcome | Frequency of cannabis use and transition from non-use to use at 18-month follow-up |
| Key Result | Generalised anxiety was independently associated with 23% increased cannabis use frequency (OR 1.23, 95% CI 1.08-1.41) and 25% increased risk of transitioning to use (OR 1.25, 95% CI 1.09-1.44) |
Where This Paper Deserves Skepticism
This is an observational study, so we cannot determine causation or rule out reverse causality (cannabis use causing anxiety symptoms). The sample comes from low-income schools in one city in Chile, limiting generalisability to other socioeconomic or geographic populations. The abstract does not disclose potential confounders (trauma, peer influence, family history, other substance exposures) or fully explain why depression and panic lost significance in multivariable analysis, which weakens confidence in the anxiety-specific claim.
Dr. Caplan’s Take
This Chilean cohort study is epidemiologically sound but reflects real-world messiness: internalising symptoms and early cannabis use cluster together, with generalised anxiety showing the strongest independent signal. I don’t interpret this as proof that anxiety causes cannabis use so much as evidence that anxious adolescents are at higher risk and warrant screening and support. The clinical implication is straightforward: when you identify an adolescent with generalised anxiety, substance use risk is part of the conversation, and evidence-based anxiety management (psychotherapy, sometimes medication) could plausibly reduce that risk, though this study doesn’t prove it.
Clinical Bottom Line
Screen adolescents with generalised anxiety for cannabis use risk and ensure they have access to effective anxiety management. Treating the underlying anxiety disorder may be a valuable prevention strategy, though this observational study cannot prove causation.
|
Have thoughts on this? Share it:
