As New York and many other states are staring down the path toward marijuana legalization, public health officials, scientists and parents alike are pushing for expedited research on its dangers.
This week, a new study appearing in Lancet Psychiatry is raising concerns over the intoxicating plant’s association with psychosis disorder. Researchers at King’s College London found that people who use cannabis daily, or who use highly potent pot, may be three times more likely to suffer their first psychotic episode.
“We are talking about people who meet diagnostic criteria [and] come to the attention of mental health services to receive treatment for psychosis,” lead study author Dr. Marta Di Forti tells CNN. “So they have to have symptoms of psychosis across the spectrum — so hallucination, delusion — that have lasted at least for a week.”
THC is the psychoactive compound in cannabis — the stuff that gets you “high.” This research supports previous studies that showed cannabis strains of 10 percent THC content or higher could be damaging to mental health.
Currently, 10 states plus the District of Columbia allow recreational cannabis; 34 more states allow only medical use. But in Europe, the drug is roundly legalized — so that’s where the research team at King’s College London began.
Dr. Di Forti’s team investigated data from from the UK, France, the Netherlands, Italy, Spain and Brazil, where it’s also legal. In their analysis, 30 percent of the 901 first-time psychosis patients they observed reported daily cannabis use, compared to seven percent of the 1,237 in the control group. In terms of using high THC strains, the comparison was 37 to 19 percent, respectively.
Those who used ultra-potent cannabis daily were five times more likely to have a first psychotic episode — leading researchers to believe that THC may be the last straw for otherwise mentally healthy individuals.
Dr. Di Forti notes that their observations do not show that psychosis is a direct cause of using cannabis; however, she warns this research should be taken into consideration especially by mental health physicians.
