Norwegian longitudinal study found increased cannabis use during youth was linked to anxiety, depression, and suicidal ideation, especially in males
In a Norwegian cohort of 1,988 young people followed over 13 years, within-person increases in cannabis use were associated with increased anxiety, depression, and over 3-fold higher suicidal ideation risk in males, and increased anxiety and suicidal ideation in females.
Quick Facts
What This Study Found
Using fixed-effects models (which control for all stable individual characteristics), increasing cannabis use from none to 10+ times/year was associated in males with anxiety (RR 1.72, p=0.009), depressed mood (RR 1.49, p<0.001), and suicidal ideation (RR 3.43, p=0.012). In females, the same increase was associated with anxiety (RR 1.38, p=0.023) and suicidal ideation (RR 2.47, p=0.002). Only for depression was the gender difference statistically significant.
Key Numbers
1,988 respondents. 4 waves over 13 years (1992-2005). 60% cumulative response rate. Males: anxiety RR 1.72, depression RR 1.49, suicidal ideation RR 3.43. Females: anxiety RR 1.38, suicidal ideation RR 2.47. Male depression association was significantly stronger than female.
How They Did This
Longitudinal cohort assessed at 4 time points over 13 years (1992-2005). 1,988 Norwegian respondents aged 11-18 at baseline. Fixed-effects modeling examining within-person associations between changes in cannabis use and changes in mental distress.
Why This Research Matters
Fixed-effects models are among the strongest observational designs because they control for all stable individual characteristics (genetics, personality, early environment). The finding that cannabis use changes track with mental distress changes within the same person strengthens the case for a direct relationship.
The Bigger Picture
The over 3-fold increase in suicidal ideation risk with heavy cannabis use in males is particularly concerning. Combined with the within-person design, this provides some of the strongest evidence to date linking cannabis use changes to suicidality changes during young adulthood.
What This Study Doesn't Tell Us
1990s cohort may not represent current cannabis use patterns (potency has increased). 60% response rate. Self-reported measures. Cannot definitively exclude reverse causation even with fixed-effects (mental distress changes could trigger cannabis use changes within waves). Norwegian context.
Questions This Raises
- ?Would these effects be larger with today's higher-potency cannabis?
- ?What drives the stronger depression association in males?
Trust & Context
- Key Stat:
- 3.4x suicidal ideation risk with heavy cannabis use in young males
- Evidence Grade:
- Longitudinal within-person design controlling for stable individual factors. Strong methodology but 1990s cohort and self-report.
- Study Age:
- 2024 study
- Original Title:
- Associations Between Cannabis Use and Mental Distress in Young People: A Longitudinal Study.
- Published In:
- The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 74(3), 479-486 (2024)
- Authors:
- Gripe, Isabella(2), Pape, Hilde, Norström, Thor(2)
- Database ID:
- RTHC-05355
Evidence Hierarchy
Watches what happens naturally without intervening.
What do these levels mean? →Frequently Asked Questions
What are fixed-effects models?
A statistical method that compares each person to themselves over time, effectively controlling for everything that stays constant about a person (genes, childhood environment, personality). This means observed effects are due to things that change over time, like cannabis use.
Why are males more affected?
The study found stronger associations for males but did not explain why. Possible factors include sex differences in cannabinoid metabolism, different patterns of use, or different vulnerabilities to cannabis effects on mood-related brain circuits.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-05355APA
Gripe, Isabella; Pape, Hilde; Norström, Thor. (2024). Associations Between Cannabis Use and Mental Distress in Young People: A Longitudinal Study.. The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 74(3), 479-486. https://doi.org/10.1016/j.jadohealth.2023.10.003
MLA
Gripe, Isabella, et al. "Associations Between Cannabis Use and Mental Distress in Young People: A Longitudinal Study.." The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 2024. https://doi.org/10.1016/j.jadohealth.2023.10.003
RethinkTHC
RethinkTHC Research Database. "Associations Between Cannabis Use and Mental Distress in You..." RTHC-05355. Retrieved from https://rethinkthc.com/research/gripe-2024-associations-between-cannabis-use
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.