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Subscribe to RSSMarijuana (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.
Griffith-Lendering agrees.
"Given the severity and impact of psychotic disorders, prevention programs should take this information into consideration," she said.
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The term "twice as likely to develop psychosis" is misleading with no quantifiers. Psychosis can be broadly defined to include Schizophrenia, Panic Disorder, Major Depression, or Bi-Polar disorders. The population as a whole (taking into account both genetic and environmental factors) has about a 1% chance of developing Schizophrenia, 1-2% chance for Bi-Polar Disorders, and 5-10% chance for Major Depression. All other things being equal, you're at a greater risk of developing a psychosis if you have a sibling who has it than you are from smoking pot. The leading theory on developing a psychosis is that you have a "threshold" almost. You can accrue different genetic and environmental factors, and you may be fine until you hit a certain point (heavy pot use, pollution related, anything) that can then trigger you.
Not really - at least not when the term is used properly. Psychosis is a loss of contact with reality that includes delusions and/or hallucinations. All of the things you mention CAN have psychosis as part of them - but, psychosis doesn't include those disorders. For example, someone can have bi-polar without psychosis; or they can have bi-polar with psychosis.
That said, I agree with the rest of your post.
How come nobody had these problems when I was growing up in the 60's and 70's before we had all of these so call professional head doctors? They think up things just to keep themselves relevant and making money. If I tell you, you have something wrong then your not responsible for what you Did.
The same studies should be done on other drug users: alcohol, caffeine, and prescription drugs.
Pot users have mental problems? What a surprise. Fits all the loser pot smokers I know.
More anti-pot propaganda.
"...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,"
But 18 year olds can legally smoke cigaretts. Pot bad, tobacco okay. Why? Money.
The minute our oh-so-concerned government finds a way to make as much money from legalized pot at they do cigaretts...it will be legal.
We keep having these experts, most of which have never smoked a joint, coming to outragious conclusions.
Everything we ingest into out bodies have an effect of one kind or another. We need to relax and quit with the scare tactics. Have you listened closely to some of the warning we get from drugs sold through TV advertising? They scare the sh!t out of me and will never use them.
Now that I'm into my 66th year of smoking pot, and am considered very smart and able, I think that "Reefer Madness" is worthless information. Smoke some pot. You will know right away if it is screwing you up.
I'm really getting bored with all this crap that has been going on for 100 years about pot. I'll tell you where the danger lies. Some people will get lazy and not go to work when high. Fire them is the answer but quit with the century old diagnostics.
@bubba Ah, so you're one of those highly intelligent people who insist there's no such thing as mental illness? Were you aware that mental illnesses such as bipolar disorder can be detected by brain scan in many cases, and that it also has a strong genetic component?
Also, regarding your ridiculous assertion that mental illness was something "made up" in the 60's or 70's so that people could shirk responsibility for their actions, my biological grandmother was born in 1896 and suffered from bipolar disorder from her early teens until her death at age 96. Both her daughters (raised separately by good, stable families) suffered from najor depressive disorder from age 12. I was born in 1961 and have been bipolar since age 11. My 13-year-old niece was diagnosed as bipolar 2 years ago. Contrary to your stereotypes, we are not a bunch of irresponsible losers. We are all punctillious about our meds, so our symptoms don't get out of control. We are loving parents, hard workers, honors students and dedicated volunteers. None of us have ever had any trouble with the law. If we make a mistake, we own it and do our best to make things right. We are good, honest, decent people.
And God forbid you, or anyone in your family, should suffer from such a thing. God forbid you should feel such pain.
Though, come to think about, I would rather feel too much, as I sometimes do, than to have such a cruel, hard heart, or be given to such a swift, ignorant judgement.
kris - great comments. We have a family member who started "self medicating" with pot at age 12 or 13. That is on top of his meds for bi-polar. He's in residential treatment now and really thinks he needs pot to feel better. His psych meds don't make him feel calm and that is what he wants.
That said, the pot smoking may have caused his decline over the last year so that he desparately needed residential care.
I'm guessing it's about 50/50 on whether the pot or the psychosis starts first. I doubt we'll ever know for sure in individual cases.
bubba - Why didn't these things exist before the 60s and 70s? They did. The genetic tendency goes back as far as the turn of the century for our family and some of the in-laws. I was raised by one parent that is probably bi-polar and the other definitely has some serious depression. Sometimes it was he!!. They don't believe in "shrinks" and think they are just fine. It's the rest of us who are "nuts".
A good percentage of adults (and teens) self medicate with booze. Mental illness is nothing new. Talking about it openly is fairly new, especially since most the mental health facilities have been shut down. You can't "hide" the afflicted any more, and good mental health services are horribly lacking. We know a lot more than we did 40 to 50 years ago, but still have a long way to go. There are some quacks out there, no doubt, but mental illness is real and it's important that the sick receive the diagnosis and care they need. With proper care, many are leading fairly normal lives.
From a ten year period of observing, an ex with bi-polar disorder and some relly awesome delusions and halucinations. It looks to me like pot reduces the delusions as an imediate effect. Sometimes the only time she could have a coherent, reality based conversation, was right after she smoked. Two weeks without pot has often coinsided with her doing something to be institutionalized. It should be one of her prescribed medications.
I also believe it slows the diseases progress, which might account for some of the confusion in the study's results. That kid that smoked pot at 16 and wnt psychotic at 19, would have gone psychotic at 16 and a half if he hadn't been smoking. Or in the case of my ex, she would have gone completely bat-crap crazy all at once, in her early twenties, or late teens, instead of only getting a little more delusional each year, until she went completely bat-crap crazy in her forties. If I seem a little flip about her condition, it's a defense mechanism to keep from getting depressed.
The junkies are out defending their drugs.
Not necessary as over the top propaganda does the trick for most people.
Can you imagine if the Pot lobbyist were as strong as Liquor or Cigarette lobbyist, how fast Pot would be legalized.
...and the ones who have NO experience with Weed are out defending their misguided BELIEFS .
It is a naturally growing WEED, put on this Earth for humans to partake of, like Broccoli .
Because some corporate lobbyist paid to have it declared ILLEGAL does not make it right or constitutionally ILLEGAL, the law passed was a SHAM & therefore illegal in & of itself .
Yes,we never knew what to call ourselves.We're "pot junkies"....You're a silly one!
Mister Fids, asbestos, lead, and mercury are also natural.
And there are those that are out just being useless.
Junkies are heroin users. I prefer to be called a pothead, or a stoner. There really is a huge difference. Junkies are more like alcoholics, than like potheads.
This is the most idiotic atricle I've ever seen on MSNBC. There is absolutely ZERO data on this supposed scientific prognosis. This is simply more anti weed propaganda for the warmongers. People on dope are more likely to attack a refrigerator than another human. What is the relationship b/w heavy cartoon watching and psychosis? Are there any economic factors? Environmental? How bout links b/w mental issues and living too close to power lines? Did any of these test subjects eat paint chips as children? NBC is a conservative nut factory and the network has sukked tremendously since losing Chris Farley and Mike Myers-no link to psychosis. How bout a study on how journalism doesn't exist anymore and there are no facts, no fact checking or factotems?
I have no feeling either way on the pot issue, but when you say this "NBC is a conservative nut factory" it tells me you must be high! You are probably the first person ever to call this site conservative.
If I got high, and saw that Fred Sanford picture, I would develop a giggle attack.
Well, it all depends on the semantics, and the confusion intentionally set off by the terms liberal, conservative, and moderate. That's why I use Statist and Individualist. Either a person is using offensive Force against peaceful and productive people or they aren't. Statists can be left, right, or center. Indvidualists can be left, right, or center. It's whether you feel righteous enough to use Force rather than persuasion. Unfortunately too many people pick and choose what they mean by liberal or conservative regardless of whether offensive Force is used, and it's based on whether they like or dislike a certain policy. That's when they will conveniently apply liberal or conservative, depending on the crowd for whom the term is a pejorative. I've learned that those who beat the conservative/liberal drum the loudest are probably Statist and they neither on YOUR side or your friend. One thing is for certain, MSNBC follows a Statist agenda and throws its support behind a particular brand, just as Foxnews follows a Statist agenda and throws its support behind another brand. Of course the two peddlers are much more similar than they are different despite the attempts at branding. Both love war, both love currency control and debasement, and both love the quixotic War on Drugs which all have eroded our financial and personal liberty beyond any sane point. Where it really counts, they are one and the same. And that's where the semantic schisms come back full circle as they toss out "liberal" and "conservative" around in to keep people at each other's throats and their eyes off what is really happening to them.
NBC just showing it's preferences.
I think they got plenty of data. They just couldn't figure out how to interpret it to suit their pre-ordained conclusions.
They should have also included the affects of alcohol and tobacco on the developing brain as well in this study to really factor in all substances that can possibly contribute to psychosis. Isn't using most substances a form of self medicating? Maybe factor in all the young adults that smoked pot in the 60's and 70's that have not developed psychosis, this study is useless.
Of course it can be a form of self-medication. I grew up with stories of "troubled" relatives being committed to state mental hospitals and others killing themselves through various methods and some just flat-out drinking themselves to death. At that time mental illness wasn't understood at all in the mainstream but during my parents' generation the suicide rate in our family dropped from around 35% to 0% because by then some of the family members were on the look-out for symptoms; even so the rate of alcoholism was still high. Then the substance abuse started in my generation. A full third of my siblings and cousins have been diagnosed with a mental illness, a couple of them pretty severe. One never did get on proper medication and abused drugs and alcohol until the last year of his life when he finally sobered up then died of cirrhosis at the age of fifty-nine. One of the most severe started in her teen years binge drinking and cutting herself and another of the more severe was an alcoholic by the time she was twenty. Another got into drugs at an early age then cleaned up years later with the help of a good therapist, proper medication, and the fact she's more stubborn than a mule and was determined to get straight.
In a nut shell, every one of them who drank or used drugs was "self-medicating", trying to escape the pain in any way they possibly could. The torture from these illnesses sometimes starts in early teenhood or before but it's often years after that before anyone realizes the person is ill.
The most researched and studied drug n history and this is all they can come up with? Sounds like there's an agenda here but it will do little to deter anyone.
More anti-pot propaganda from the government. They will just not give up. No one has ever died or been harmed in anyway by pot.
Although I'm on your side of the issue, I cannot just let that one go. There is almost no way for that to be true. Don't make absolute statements that might come back to bite your ass.
Apologies for nitpicking.
Sorry Gary is right. Try to find any no-bias study that shows different.
Really, no body has ever got behind the wheel of a car while on pot and died because of it or killed somebody because of it? While pot itself might not kill what you do under its influence can and to say nobody has ever been harmed by it is just ridiculous.
The percentages of deaths directly related to marijuana are so small one could truthfully say that none have occurred.
I think the point of this story, and the poster above, is the health problems caused by pot. Not some car accident cause you are too high.
I don't really know any statistical percentages or have "no-bias studies", there is absolutely no way that smoking all your life doesn't cause some lung damage, brain damage along with other things.
People rarely die exclusively from anything (except maybe a plane crash). So, no, pot has not been the exclusive cause of harm or death.
Who says you have to smoke it?
uhhh... EVERYBODY DIES from some sort of damage to their body........
whose brain are you using and why did they loan it to you ?
Mister Fids,
And marijuana can damage the body. Thanks for your help and personal attack. If you are a smoker, you can never claim that pot makes people peaceful and kind.
Enough,
Good point. But he said:
It's simply not true.
And by the way, guys, I live in Colorado and voted for Amendment 64. I'm on your side, but the fact that you cannot admit that his statement cannot be true and are violating the CoH (Mr. Fids) is really sad. I don't think pot is generally harmful at all. But you absolutely cannot make the claim that it is never, ever harmful.
Makes you look like fundamentalists.
And your scientific proof is......????????
Even my elderly parents are to the point they think small amounts of pot in one's possession should be ignored. Too many rapists and murderers getting by with short prison terms while others are spending 10 or 20 years in jail for pot possession. Stupid and totally inefficient. They don't like street drugs, but anyone with half a brain knows alcoholism and abuse of prescription painkillers are worse problems than pot.
Sure pot can be a gateway drug, just like booze and skimming some of mom or dad's "legal" hydrocodone. Middle aged adults are overdosing on that stuff and/or graduating to heroin and overdosing. Children of the 60s and 70s. I don't know of anyone who overdosed on pot and died (unless it was laced with something).
Carrying on about pot IS a diversion to steer people away from focusing on our already legal addictions. Make small amounts of pot legal and tax the heck out of it.
Not to nitpick Hambone, but show some evidence that pot causes any harm at all to the body. As near as I or the study in the article can tell, it either helps, or nobody knows. I do beieve it's not totaly impossible to hurt somebody with pot. I just don't believe there is any proof that it's ever been done. The list of it's benefits however, is so long as to be unbelievable to most. A quick google of "canabinoid research", will bear that out.
That just isn't true, gary. You can say it all you want and convince yourself if you like, but it isn't true.
Ram - Can you post some links to support it has caused harm? Where it states that this blabla was caused by only POT use?
No other drugs involved Alcohol / meth / pain killers?
What psychosis? I grew up in the 70's in NYC and dont have to explain how much spot was smoked. By thousands/millions of people at every occasion. And I don't know anyone who developed a psychosis.
Bullcrap studies to make it seem like pot is so bad.
tfnj, you were lucky then. I grew up then too & did know people who developed psychosis after only pot use. sure, it wasn't/isn't that common, but just because you didn't know of any cases, doesn't mean it didn't happen or isn't still happening.
Name the psychosis and give me an example. Sorry but if you reply to me I'm gonna call you out. I didn't just post that by using examples from my past. I also have basic knowledge of how pot can affect the body.
I want to see the same study done on alcohol. I was a straight-edge kid, but in my personal experience growing up, I can definitely say it was alcohol that caused more problems than pot in teens. I think if mental illness is in someone's biology, it's only a matter of time before it surfaces. Drug/alcohol use may cause it to surface earlier or exacerbate symptoms (but sometimes mute them), but I think it's just going to manifest eventually.
There was an article here or on huffington on a study of grey brain matter in drug users. They found no change in cannabis users. Alcohol on the other hand messed their brains up.
Read the same article. I believe it said that there was no change in the white matter of the brain when studying teenagers and pot usage, but there was significant noticeable change in the white matter in teenagers who drank. The article was in several different sources.
I wonder if these loser kids that are going out and gunning down innocent people in theaters and schools are taking Big Pharma and FDA approved drugs...bet that one would be swept under the rug...
But if their moronic study and waste of (probably) tax payers money were right...25% of ALL of us would be suffering from psychosis...
And Obama has a very high probability according to this study to be psychotic.
I was going to post a long rambling comment here but I lost interest......
I forgot what I was gonna say
Ahh the days of $20 ounces..........
I recently asked a younger friend:
Hey do I still need to break out a record album cover to remove seeds?
He laughed at me.
Gosh, TFNJ. You must be as old as I am. lol. $10 bags and seeds. Now it's $60 1/8s and they keep the seeds.
Bubba, I was around in the 60s and 70s and my major clinical depression was definitely triggered by pot smoker. Over the past 35 years, I have spoken to dozens and dozens of people who experienced the exact same thing. Smoke a lot of pot, get paranoia, the paranoia never goes away until you go to the doctor and go on antidepressants for the rest of your life, if you don't believe me, than you are ignorant. Pot is not a safe drug for a lot of people. Sorry, potheads, but it's true.
All I know is that my doctor has prescribed me all types of pills for my ills and they all sucked. Cannabis works. Just let me have my plant and live my life in peace.
Oh hell, just pass that doobie!
I remember the days when people sold loose joints. yeah I'm old.
Cannabis Falsehood #876 You don't "see things" when your high. Your imagination is going 10 miles an hour but what you see doesn't turn into false reality.
I agree. I mean you might over analyze something, like "Wow man the invention of the cup is amazing". But that's not a psychosis or anything.
On LSD. I haven't seen adults trip on cups, other than in bad comedies.
If THC is so harmful why does the human body naturally produces it own version called Anandamide?
The researchers in the article didn't say it was harmful. They said they couldn't say. They had difficulty proving that it's not harmful, because it's always difficult to prove a negative. They had difficulty proving that it's harmful, because it's not harmful.
Tell you what. Legalize marijuana and let's see how our teenagers develop and not rely on some supposed study about psychoses. Maybe the psychotic teens were just the ones who were so driven to obtain illegal marijuana that they were going to develop the psychosis anyway.
Looking for 50+ years for some serious negative stuff.
Just can't find it.
Damn!!
What a load of crap. Legalize marijuana and shut the @!$%# up already.
agreed
This is absurd beyond words. I'm just shaking my head. The incidence of marijuana smoking related episodes of psychosis is so incredibly low that I'm surprised that someone even bothered to fund this study. It's just absurd.
I believe this to be very misguiding. Just because some random act of events happen to you at 16, does not mean your going to become a pot head at 19 by way of psychosis from the events when you were 16. I say smoke get high and above all be happy!!!
This article sounds more like junk science. I knew a lot of people who smoked pot when they were teenagers and most of them never exhibited psychotic symptoms. That was more than 30 years ago. Some of those people have continued to smoke marijuana. Perhaps people already pre-disposed to psychosis may be affected adversly by pot smoking, but they would probably be adversly affected by any other drug including alchohol. I have also traveled to India where smoking ganga (a consentrated form of marijuana) is common place, albiet use is most prominent among the lower income or disadvantaged people. There is a greater tendency for people who use this stuff to be apathetic or display passive behavior.
What about the tens of millions of us[in the us alone] who used pot- a lot.here we are middle aged and no psychosis as teens
Perhaps we got stoned, and missed it.
I do know people who get paranoid when they smoke (or used to smoke) pot. I for one, laughed like crazy, ate like a little piggie, and went to sleep.
thank you Julia, I too know people who got paranoid smoking pot. even heard Billy Bob Thorton say on a talk show that he had to stop using it because he would get so paranoid he thot the FBI was after him.