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

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).

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.

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 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.

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.