NEW YORK (Reuters Health) - Marijuana (cannabis) use may be linked to the development of psychotic symptoms in teens - but the reverse could also be true: psychosis in adolescents may be linked to later pot use, according to a new Dutch study.
"We have focused mainly on temporal order; is it the chicken or the egg? As the study shows, it is a bidirectional relationship," wrote the study's lead author Merel Griffith-Lendering, a doctoral candidate at Leiden University in The Netherlands, in an email to Reuters Health.
Previous research established links between marijuana and psychosis, but scientists questioned whether pot use increased the risk of mental illness, or whether people were using pot to ease their psychotic symptoms, such as hallucinations and delusions.
"What is interesting in this study is that both processes are going on at the same time," said Dr. Gregory Seeger, medical director for addiction services at Rochester General Hospital in upstate New York.
He told Reuters Health that researchers have been especially concerned about what tetrahydrocannabinol (THC), the active property in pot, could do to a teenager's growing brain.
"That's a very vulnerable period of time for brain development," and individuals with a family history of schizophrenia and psychosis seem to be more sensitive to the toxic effects of THC, he said.
A 2010 study of 3,800 Australian teenagers found that those who used marijuana were twice as likely to develop psychosis compared to teens who never smoked pot.
But that study also found that those who suffered from hallucinations and delusions when they were younger were also more likely to use pot early on.
CHICKEN v. EGG
For the new study, published in the journal Addiction, the researchers wanted to see which came first: pot or psychosis.
Griffith-Lendering and her colleagues used information on 2,120 Dutch teenagers, who were surveyed about their pot use when they were about 14, 16 and 19 years old.
The teens also took psychosis vulnerability tests that asked - among other things - about their ability to concentrate, their feelings of loneliness and whether they see things other people don't.
Overall, the researchers found 940 teens, or about 44 percent, reported smoking pot, and there was a bidirectional link between pot use and psychosis.
For example, using pot at 16 years old was linked to psychotic symptoms three years later, and psychotic symptoms at age 16 were linked to pot use at age 19.
This was true even when the researchers accounted for mental illness in the kids' families, alcohol use and tobacco use.
Griffith-Lendering said she could not say how much more likely young pot users were to exhibit psychotic symptoms later on.
Also, the new study cannot prove one causes the other. Genetics may also explain the link between pot use and psychosis, said Griffith-Lendering.
"We can say for some people that cannabis comes first and psychosis comes second, but for some people they have some (undiagnosed) psychosis (and) perhaps cannabis makes them feel better," said Dr. Marta Di Forti, of King's College, London, who was not involved with the new research.
Di Forti, who has studied the link between pot and psychosis, told Reuters Health she considers pot a risk factor for psychosis - not a cause.
Seeger, who was also not involved with the new study, said that there needs to be more public awareness of the connection.
"I think the marijuana is not a harmless substance. Especially for teenagers, there should be more of a public health message out there that marijuana has a public health risk," he said.
"Given the severity and impact of psychotic disorders, prevention programs should take this information into consideration," she said.
SOURCE: http://bit.ly/Rr63N8 Addiction, online December 7, 2012.
Again, this well paid scientists just speak out what they have been told to tell us, some weird explanations for normal natural incidences of diseases, like psychosis in youth and adults so this could be used as an argument against the long outstanding re-lagalisation of Cannabis.
In fact, all this has been studied and reported already many years ago, and all this allegations against Cannabis use are without any substance at all.Just a paragraph from an important official report pg.20#3:Cannabis - The Benign Herb The official Empirical Studies into actual use of cannabis conclude:
1) use of Cannabis has no adverse effect upon mental or physical health: Cannabis is harmless;
2) use of Cannabis does not cause any impairment to mental and physical abilities: Cannabis is safe;
3) modern Medical Case Histories show Cannabis to have numerous beneficial results to health: Cannabis is benign.
THE REPORT. CANNABIS: THE FACTS, HUMAN RIGHTS AND THE LAW ISBN 9781902848204.
@JuergenMeixner I disagree with the notion that cannabis doesn't cause and mental or physical issues - I dated a guy (yrs ago) who was a avid pot smoker. I was not, so, his "issues" when high were perplexing to me...... Let's just say, one of them being he couldn't always "perform" while high. As for the mental issues, I've seen otherwise. While this may not be common in all users, you must remember, Aspirin is safe, Tylenol is safe - but when used incorrectly or too much, it is no longer safe. Every safe drug can be not so safe. If every drug that claimed to be safe was - well, it wouldn't need the paperwork stating that SOME people may experience side effects. Not all safe drugs are safe for everyone. Everyone is different. You have noticed all these new drugs that have lawyers salivating?
On the other side, the VA has told my husband on several occasions the following, "Should marijuana become legal in this state, it would benefit you greatly. In some studies it has shown to be more effective in the treatment of migraines. More so than any other course of treatment for some." So basically, to combat the traumatic brain injury (to include actual brain damage), his VA neuro dr and one primary health care dr have both given him the green light to get high. The medications he's on for pain due to 4 herniated disks & pinched nerves (throughout his back, not just one place) and the chronic, often debilitating migraines, could be eased with a joint.
I'm guessing these researchers didn't see the research published last week stating that marijuana doesn't effect or destroy brain cells or brain development of minors, but alcohol does. Another hit piece from the anti-legalization parties.
slowly ruining our Country with this crap. Get well America so good people can live his or her life without this mess.