I recently had an interesting discussion with one of our residents about the risk of developing schizophrenia after experiencing substance-induced psychosis. The conversation was sparked by a study based on data from the Danish Civil Registration System. Fun fact: when you see large data sets like this, they’re often from Scandinavian countries.
The study followed 6,788 people who were diagnosed with substance-induced psychosis between 1994 and 2014. They tracked patients until they developed schizophrenia, bipolar disorder, or passed away, using statistical methods to calculate the risk of conversion to a serious mental illness.
A key takeaway: this study didn’t just look at the risk of schizophrenia but also included bipolar disorder and various substances—not just cannabis. Overall, 32.2% of people with substance-induced psychosis went on to develop either schizophrenia or bipolar disorder. Cannabis-induced psychosis had the highest conversion rate, with 47.4% of those cases developing one of these disorders.
Being young and male increased the likelihood of developing schizophrenia, and self-harm after substance-induced psychosis was also linked to a higher risk of both schizophrenia and bipolar disorder.
The big takeaway here? Substance-induced psychosis is closely associated with the development of serious mental illnesses. Follow-up care is essential, and steering clear of cannabis is always a smart move.
Link to the article: https://psychiatryonline.org/doi/10.1176/appi.ajp.2017.17020223