Frequent cannabis use in Ontario youth was linked to both internalizing and externalizing symptoms, especially in girls
Among Ontario youth aged 12-17, frequent cannabis use was associated with elevated anxiety/depression symptoms and conduct/ADHD symptoms, with significantly stronger associations in females than males.
Quick Facts
What This Study Found
Frequent cannabis use was associated with elevated externalizing symptoms (OR 2.17 in males, 5.13 in females) and internalizing symptoms (OR 2.07 in males, 3.40 in females). These associations persisted after adjusting for binge drinking, smoking, and parenting factors.
Key Numbers
Externalizing: OR 2.17 (1.80-2.62) males, 5.13 (4.24-6.21) females. Internalizing: OR 2.07 (1.74-2.47) males, 3.40 (2.73-4.24) females. Associations persisted after adjusting for confounders.
How They Did This
Cross-sectional analysis of the 2014 Ontario Child Health Study using the Emotional and Behavioural Scales. Logistic regression estimated associations between cannabis use frequency and elevated symptoms, with replicate bootstrap weighting for design effects.
Why This Research Matters
The markedly stronger associations in females suggest that girls who use cannabis frequently may be particularly vulnerable to mental health effects, which has implications for targeted prevention.
The Bigger Picture
The sex difference in the strength of associations raises important questions about whether biological factors, social context, or both explain why frequent cannabis use appears more strongly linked to mental health symptoms in girls.
What This Study Doesn't Tell Us
Cross-sectional design cannot determine whether cannabis use preceded or followed the development of symptoms. Self-reported cannabis use may be underreported. The study cannot distinguish between different cannabis products or potencies.
Questions This Raises
- ?Why are associations stronger in females?
- ?Do girls with mental health symptoms use cannabis to self-medicate, or does cannabis affect girls differently?
- ?Would longitudinal data confirm these cross-sectional associations?
Trust & Context
- Key Stat:
- Externalizing symptoms OR: 5.13 in females vs 2.17 in males
- Evidence Grade:
- Moderate: large population-based sample with validated measures, though cross-sectional design limits causal inference.
- Study Age:
- Published in 2020 in Journal of Adolescent Health.
- Original Title:
- Cannabis Use and Internalizing/Externalizing Symptoms in Youth: A Canadian Population-Based Study.
- Published In:
- The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 67(1), 26-32 (2020)
- Database ID:
- RTHC-02575
Evidence Hierarchy
A snapshot of a population at one point in time.
What do these levels mean? →Frequently Asked Questions
What are internalizing and externalizing symptoms?
Internalizing symptoms are directed inward, like anxiety and depression. Externalizing symptoms are directed outward, like conduct problems and attention difficulties. This study found frequent cannabis use was associated with both types.
Why were effects stronger in girls?
The study found that associations between frequent cannabis use and both types of symptoms were 2-3 times stronger in females. The reasons are unclear but could involve biological differences in how THC is processed, different patterns of use, or different social contexts.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-02575APA
Girgis, Joseph; Pringsheim, Tamara; Williams, Jeanne; Shafiq, Samreen; Patten, Scott. (2020). Cannabis Use and Internalizing/Externalizing Symptoms in Youth: A Canadian Population-Based Study.. The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 67(1), 26-32. https://doi.org/10.1016/j.jadohealth.2020.01.015
MLA
Girgis, Joseph, et al. "Cannabis Use and Internalizing/Externalizing Symptoms in Youth: A Canadian Population-Based Study.." The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 2020. https://doi.org/10.1016/j.jadohealth.2020.01.015
RethinkTHC
RethinkTHC Research Database. "Cannabis Use and Internalizing/Externalizing Symptoms in You..." RTHC-02575. Retrieved from https://rethinkthc.com/research/girgis-2020-cannabis-use-and-internalizingexternalizing
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.