WASHINGTON: The longer people use cannabis or marijuana, the more likely they are to experience hallucinations or delusions or to suffer psychosis, according to a study released Saturday.
The study found that people who first used cannabis when they were aged 15 or younger were twice as likely to develop a "non-affective psychosis" - which can include schizophrenia - than those who had never used the drug.
The research led by John McGrath from the University of Queensland in Australia was based on a survey of 3,801 people with an average age of 20.1 years, the American journal Archives of General Psychiatry reported.
The study is based on a group of children born at Brisbane's Mater Hospital during the early 1980s.
Most convincing evidence yet
"Among all the participants, a longer duration since the first time they used cannabis was associated with multiple psychosis-related outcomes," the study said.
Of the group, 17.7% reported using cannabis for three or fewer years, 16.2% for four to five years and 14.3% for six or more years.
Sixty-five were diagnosed with "non-affective psychosis", such as schizophrenia, and 233 had at least one hallucination, the study said.
"This is the most convincing evidence yet that the earlier you use cannabis, the more likely you are to have symptoms of a psychotic illness," McGrath said.
Cannabis-psychosis relationship is complex
"Individuals who had experienced hallucinations early in life were more likely to have used cannabis longer and to use it more frequently," it said.
But the relationship between psychosis and cannabis use was complex.
People who were vulnerable to psychosis, in other words had isolated psychotic symptoms, "were more likely to commence cannabis use, which could then subsequently contribute to an increased risk of conversion to a non-affective psychotic disorder," the research said.
The article said previous studies had also identified an association between cannabis use and psychosis but there were concerns that research had not adequately accounted for confounding variables.
Schizophrenia is a serious disorder that affects about one in a 100 Australians, and usually first presents in young adults. This is also the time when the brain seems most vulnerable to cannabis.
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LONGER usage, or EARLIER usage?
I'd love to read the research paper that is referenced in this article, if anyone has a link, can they post it up?
It seems to be that the conclusion would be better expressed as, "The EARLIER one uses marijuana, the more likely problems may develop later in life". But that statement too has its problems, as is noted in all studies of this kind, as it is next to impossible to know which came first, the problem or the marijuana.
If we did similar studies between people that drink coffee and people that are depressed, I wonder what figures we'd turn up? Similarly with tobacco, alcohol and even caffeine, i'm curious what figures would be turned up? I assume that the reason why such a study hasn't been done is because it would seem ridiculous from the onset, because of the social acceptability of such substances, and the impossibility in determining which was the original factor and what contributes to what.
It's the stigma of mental-health research and substances. Sometimes there are clear findings, which are testable, other times there are not.
In Lak'ech Ala K'in
Vague
I don't even know what this is trying to say...
What age group did they study? etc "early 1980s"..?
Vague and annoying.
very suspect study
I would really love to see the raw data behind this. First of all.. "Individuals who had experienced hallucinations early in life were more likely to have used cannabis longer and to use it more frequently,"
What is defined as hallucinations? Day dreaming is a form of hallucination, yet it has nothing to do with drugs. But at the same a drug like marijuana probably does invoke more day dreaming. That doesn't mean it's particularly 'bad' or linked to psychosis.
Then states...
"People who were vulnerable to psychosis, in other words had isolated psychotic symptoms, "were more likely to commence cannabis use, which could then subsequently contribute to an increased risk of conversion to a non-affective psychotic disorder," the research said. "
Which does not in anyway show that using marijuana is 'linked' to psychosis, only that those already vulnerable to psychosis, tend to use marijuana. Of course putting a spin on it to make it sound 'bad' or somehow linked.
Typical propaganda BS.
Says it all doesn't it!
Well this line says it all doesn't it!
"Individuals who had experienced hallucinations early in life were more likely to have used cannabis longer and to use it more frequently"
People who have mental disorders and/or at risk of, seek these kinds of drugs out. The drug doesn't cause the problem, people with the problem choose to use the drug.
People have used it for 1000's of years. With all the millions of people smoking it we should see a stiff increase of mental health patients, but we just don't see that anywhere in the world.
So when will the newspapers/mags/governments stop beating this dead horse? It's been getting beaten since the 1930's, that Pot makes you go nuts. Come on, can't you see the pot smokers of the world will NEVER belive it anyhow, because they just don't see it in their daily lives.
Link to study
http://archpsyc.ama-assn.org/cgi/content/full/2010.6?home
People with 'mental' problems tend to self medicate.
People with 'mental' problems tend to self medicate.
The medicine doesn't cause the problem, the problem causes people to take medicine.
Millions of people worldwide smoke cannabis without problems...
Some people are allergic to peanuts, it really messes them up, let's ban peanuts. (It is natural, it grows on it's own in nature.)
What's the diff? Some people are allergic to cannabis, it really messes them up, let's ban cannabis. (It is natural, it grows on it's own in nature.)
Old news, old propaganda.
Cannabis was banned so petroleum oil could replace hemp oil, and so cotton could replace hemp fabrics.
Can't trade in slaves for nothing, can't push petroleum oil for nothing.
People wake up, smoke up! Jah bless...