Study Links Daily Marijuana Use To Pyschosis
Date Posted: Wednesday, March 20th, 2019
People who use marijuana every day are more likely to experience psychosis, according to a new study published Tuesday by the journal The Lancet Psychiatry. And daily use of particularly potent marijuana ups the risk of developing psychosis even more.
The study's findings are in line with previous research pointing to a link between cannabis use and psychosis – a condition when someone loses grip on reality – though the new research does not definitively find a causal relationship between marijuana and mental health issues.
Researchers at King's College London and elsewhere in Europe surveyed patients 18 to 64 at 11 sites in Europe and one in Brazil who had experienced a first episode of psychosis between 2001 to 2015.
The researchers then took over 900 patients with psychosis and compared them to a control group of healthy people, collecting information about the participants' history of cannabis use and the use of other drugs. If the level of THC – the active ingredient in cannabis – in the drug used by participants was above 10 percent, the researchers classified that marijuana as "high-potency."
Adjusted for other factors, people who used cannabis daily were three times as likely to be diagnosed with an initial episode of psychosis, and people who used high-potency cannabis were about five times more likely to develop psychosis, according to the research.
"As the legal status of cannabis changes in many countries and states, and as we consider the medicinal properties of some types of cannabis, it is of vital public health importance that we also consider the potential adverse effects that are associated with daily cannabis use, especially high potency varieties," Marta Di Fori, lead author of the study, said in a statement.
The link between marijuana use and psychosis was particularly noticeable among patients in Amsterdam and London, where high-potency cannabis is very common: In Amsterdam, 4 in 10 new cases of psychosis were linked to daily cannabis use, while half of all cases were linked to high-potency use. In London, 2 in 10 cases were linked to daily use, while 3 in 10 were linked to high-potency use.
If high-potency marijuana was no longer available, researchers predicted the incidence of psychosis in Amsterdam would be slashed in half.
Date Posted: Wednesday, March 20th, 2019 , Total Page Views: 671