rethinkTHC Search
Menu
Study breakdown

Four distinct trajectories of cannabis use disorder severity identified in young Swiss men

Longitudinal CohortStrong evidence
The takeaway

Among nearly 6,000 young Swiss men tracked from age 20 to 25, four distinct trajectories of cannabis use disorder severity emerged, with mental health problems, peer drug use, and parental relationships predicting who stayed stuck in problematic use.

Addiction researchers, clinicians working with young adults, and anyone interested in the natural course of cannabis use disorder.

88.2% stayed at low severity; only 2.6% remained persistently high

What the researchers found

Four trajectories were identified: stable-low (88.2%), decreasing (5.2%), stable-high (2.6%), and increasing (4.0%). Predictors of persistent high severity versus decreasing included major depression (OR 1.19), ADHD severity (OR 1.25), antisocial personality disorder (OR 1.18), poor parental relationships (OR 0.74), friends with drug problems (OR 1.33), and neuroticism-anxiety (OR 1.35).

Why it matters

Most young men with cannabis use disorder symptoms naturally improve over time. Identifying the roughly 3% who remain stuck in high-severity use allows for targeted early intervention rather than broad-brush approaches.

The numbers in context

5,987 men; ages 20-25; 88.2% stable-low; 5.2% decreasing; 2.6% stable-high; 4.0% increasing; depression OR 1.19; ADHD OR 1.25; friends with drug problems OR 1.33

How the study worked

Latent class growth analysis of 5,987 Swiss men assessed at mean ages 20, 21.5, and 25 years. Cannabis Use Disorders Identification Test-Revised (CUDIT-R) measured severity at each wave. Predictors from six domains (cannabis use, family, peers, other substances, mental health, personality) were assessed at age 20.

What this study cannot tell us

Male-only Swiss sample limits generalizability. Self-reported measures. Effect sizes were small. Predictors measured at one time point may not capture dynamic changes. Three waves may miss important transitions.

How to read the evidence

Large longitudinal cohort with appropriate growth modeling, though male-only and single-country limitations.

When this study was published

Published in 2021.

The bigger picture

The finding that nearly 9 in 10 young men stayed at low severity, and most who started high improved, challenges the narrative that cannabis use disorder inevitably worsens. The small group with persistent problems had identifiable risk factors that could guide targeted interventions.

Questions still open

  • Would similar trajectories emerge in women or other cultural contexts? Could intervening on modifiable predictors (peer networks, mental health treatment) shift people from stable-high to decreasing trajectories? Do these trajectories predict outcomes beyond age 25?

Common questions

Do most young men with cannabis problems get better on their own?
In this study, most did. The majority stayed at low severity (88.2%), and another 5.2% started high but decreased. Only 2.6% remained at persistently high severity.
What predicted staying stuck in problematic use?
Depression, ADHD, antisocial personality features, poor parental relationships, having friends with drug problems, and higher neuroticism-anxiety at age 20 all predicted remaining at high severity rather than improving.

Read the original research

Cannabis use disorder trajectories and their prospective predictors in a large population-based sample of young Swiss men.

Addiction (Abingdon, England), 116(3), 560-570

Citation

Marmet, Simon; Studer, Joseph; Wicki, Matthias; Gmel, Gerhard. (2021). Cannabis use disorder trajectories and their prospective predictors in a large population-based sample of young Swiss men.. Addiction (Abingdon, England), 116(3), 560-570. https://doi.org/10.1111/add.15177

Explore the wider topic