An inquiry into a neighbor’s suicide leads a man to discover links between heavy marijuana use and psychosis among people who suffer from mental illnesses:
One afternoon recently, I met Dr. Roger Roffman, professor emeritus at the University of Washington’s School of Social Work, in his office up on Roosevelt Way. He has a calm demeanor and a cozy office set up for counseling sessions: He has been studying marijuana dependence for nearly 30 years. I had sent him the police report about Rosado in advance. He offered me some tea and then sat on the couch under his third-floor window and said, ‘The research would tend to indicate that she was loaded for an explosion.’
The moment he began to speak, it began to rain.
He said what loaded her for an explosion was being sexually abused as a child and then using marijuana heavily and then experiencing psychosis. Citing data from UK researchers published in Psychological Medicine in 2011, he said, ‘In some case examples where forced nonconsensual sex occurred during childhood, there was a risk from that experience for later psychotic illness, and that risk was exaggerated, made even greater, if the individual used marijuana.’ In the data, researchers found that if an individual’s sexual trauma and marijuana use both began before the age of 16, their chances of being diagnosed with psychosis later on was ‘over seven times’ greater. The researchers wrote that among other stress factors thought to contribute to psychosis—like ethnicity, employment, drug use, and family history of mental illness—sexual trauma was one ‘few researchers had acknowledged.’