People with Cannabis Use Disorder Had 22 Times the Suicide Attempt Rate of the General Population

The crude suicide attempt rate among people with cannabis use disorder was 2.5 per 1,000 person-years, over 22 times higher than the general population. Risk was higher in females, people with co-occurring alcohol use disorder, those with any psychiatric diagnosis, within one year of first treatment visit, and during the COVID-19 period.

Retrospective cohort study using electronic health records from Bologna, Italy, identifying individuals diagnosed with cannabis use disorder from 2009-2019 and tracking their emergency department visits for suicide attempts through the same period.

The 22-fold higher suicide attempt rate underscores that cannabis use disorder is not a benign condition and is associated with serious mental health consequences. The elevated risk in the first year after initial clinical contact highlights a critical window for intervention.

This study adds to the evidence that substance use disorders, including cannabis, are associated with significantly elevated suicide risk. Given the high prevalence of cannabis use globally, even a small proportion developing use disorder with elevated suicide risk represents a substantial public health burden.

Observational study that cannot establish whether cannabis use disorder causes elevated suicide risk or both share common underlying factors (depression, trauma, other psychiatric conditions). ICD coding may not capture all cannabis use disorders. Single Italian metro area. Cannot distinguish between cannabis and concurrent substance use effects on suicide risk.