Substance-induced psychosis increases the risk of suicide attempts tenfold

While substance-induced psychosis previously has been linked to an increased risk of suicide, the connection to suicide attempts has remained unclear. A new Danish register-based study investigates this relationship and finds that individuals with substance-induced psychosis have a significantly elevated risk of subsequent suicide attempts. The results highlight the need for much greater attention and follow-up for this vulnerable patient group.

The study includes all individuals in Denmark over the age of 13 during the period from 1995 to 2017, using data from national health registers. A total of 8,900 individuals were diagnosed with substance-induced psychosis (79% men), of whom 740 later attempted suicide. Using hospital data and ICD-10 codes, researchers calculated that individuals with substance-induced psychosis had a 13-fold higher risk of suicide attempts compared to the general population.

However, the risk varied depending on the type of substance: psychosis induced by opioids carried the highest risk, followed by alcohol, benzodiazepines, cocaine, and cannabis. Within 20 years of the substance-induced psychosis, approximately 15% of patients had attempted suicide.

Substance-induced psychosis is a risk factor for later suicide attempts. This study points to the need for systematic follow-up and interdisciplinary intervention to prevent suicide among individuals experiencing psychosis related to substance use—a group that is often overlooked in the treatment system.