Schizophrenia link to cannabis denied

By chillinwill · Aug 29, 2009 · ·
  1. chillinwill
    A STUDY by North Staffordshire academics has rejected a link between smoking cannabis and an increase in mental illness.
    The research found there were no rises in cases of schizophrenia or psychoses diagnosed in the UK over nine years, during which the use of the drug had grown substantially.

    Pro-cannabis campaigners seized on the results as supporting the legalising of cannabis, and claimed the report had been suppressed.
    But the leading expert behind the study said it could be too low-key to re-ignite the debate on whether restrictions should be removed from soft drugs.

    From their base at the Harplands Psychiatric Hospital in Hartshill, the four experts reviewed the notes of hundreds of thousands of patients at 183 GP practices throughout the country to look for any changing rate in cases of schizophrenia.

    The work had been set up to see if earlier forecasts from other experts had been borne out, that the mental disorder would soar through the growing popularity of cannabis.

    Published in the Schizophrenia Research journal, a paper on the study said: "A recent review concluded that cannabis use increases the risk of psychotic outcomes.

    "Furthermore an accepted model of the association between cannabis and schizophrenia indicated its incidence would increase from 1990 onwards.

    "We examined trends in the annual psychosis incidence and prevalence as measured by diagnosed cases from 1996 to 2005 and found it to be either stable or declining.

    "The casual models linking cannabis with schizophrenia and other psychoses are therefore not supported by our study."
    The research was conducted by Drs Martin Frisher and Orsolina Martino, from the department of medicines management at Keele University; psychiatrist Professor Ilana Crome, from the Harplands academic unit, who specialises in addiction; and diseases expert Professor Peter Croft, pictured below, from the university's primary care research centre.

    Its findings come shortly after the Government reclassified cannabis from Class C to Class B, which invokes heavier penalties.
    Yet Dr Frisher revealed last night that the study had been partly commissioned by the Government's advisory committee on the misuse of drugs.

    He said: "We concentrated on looking into the incidence of schizophrenia during those years and not specifically at cannabis use.
    "It was relatively low-key research so I don't believe it will re-ignite the debate on whether the drug should be legalised."
    Hartshill-based Dilys Wood, national co-ordinator of the Legalise Cannabis Alliance, said that so far the report had been published in medical journals and would have a far-reaching reaction if it surfaced more widely.

    She added: "I believe that if it had found a causal link between cannabis and schizophrenia it would have been all over the press.
    "The public needs to know the truth about drugs; not more Government-led propaganda."

    And Alliance press officer Don Barnard said: "It is hard to believe the then Home Secretary Jacqui Smith did not know of this very important research when deciding to upgrade cannabis to Class B."

    The team said a number of alternative explanations for the stabilising of schizophrenia had been considered and while they could not be wholly discounted, they did not appear to be plausible.

    August 27, 2009
    This Is The Sentinel

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  1. Nature Boy
    Doubt cast on cannabis, schizophrenia link

    Doubt cast on cannabis, schizophrenia link

    A new study in the UK has cast doubt on the supposed link between cannabis use and schizophrenia.

    But at least one Australian researcher says the study needs more evidence.

    Previous research has suggested cannabis use increases the risk of being diagnosed with either psychosis or schizophrenia.

    This latest study, led by Dr Martin Frisher of Keele University, examined the records of 600,000 patients aged between 16 and 44, but failed to find a similar link.

    "An important limitation of many studies is that they have failed to distinguish the direction of association between cannabis use and psychosis," the authors write in the latest edition of the journal Schizophrenia Research.

    They point out that "although using cannabis is associated with a greater risk of developing psychosis, there is also evidence of increased cannabis use following psychosis onset."
    Not as predicted

    Frisher and colleagues compared the trends of cannabis use with general practitioner records of schizophrenia and psychosis.

    They argue if cannabis use does cause schizophrenia, then an increase in cannabis use should be followed by an increase in the incidence of schizophrenia.

    According to the study, cannabis use in the UK between 1972 and 2002 has increased four-fold in the general population, and 18-fold among under-18s.

    Based on the literature supporting the link, the authors argue that this should be followed by an increase in schizophrenia incidence of 29% between 1990 and 2010.

    But the researchers found no increase in the rates of schizophrenia and psychosis diagnosis during that period. In fact some of the data suggested the incidence of these conditions had decreased.

    "This study does not therefore support the specific causal link between cannabis use and the incidence of psychotic disorders," the authors say. "This concurs with other reports indicating that increases in population cannabis use have not been followed by increases in psychotic incidence."
    More evidence

    Professor Joseph Rey of the Faculty of Medicine at the University of Sydney, who's previous research has identified a link between cannabis and schizophrenia, is sceptical of the study's results.

    "Not showing that there is a link does not mean there is no link," he says. "There might be other factors at play that may reduce the incidence of diagnosed schizophrenia."

    According Rey, "this study is just a start and the evidence suggesting that cannabis use does increase the risk of schizophrenia is quite strong. We need more evidence to counteract what we already know."

    The authors of the study say that while they cannot completely dismiss all alternative explanations of their data, such explanations "do not appear to be plausible".

    01 Sep 2009
    Michael Slezak
  2. bubbly nubs
    Re: Doubt cast on cannabis, schizophrenia link

    Seems to me like there's a new study every month saying the opposite. Somebody is doing these tests wrong surely?
  3. Amnesia
  4. anonuser30500
    Re: Doubt cast on cannabis, schizophrenia link

    Swim actually thinks that the links are mostly anecdotal, with various patients reporting to psychiatrists, counsellors and health 'experts'.

    The link with cannabis is likely to be a simple trigger to launch what was there in the first place. So, a Swim with some recognition of 'not feeling right' (you would know something was wrong if you were schizophrenic) might smoke a reefer and, the mild yet very real psychoactive effect, triggers the condition.

    He or she reports this which is why we hear cannabis linked. People assume that, had the Swim not used cannabis, then he or she would be hunky dory, top of the tree and so on.

    Swims neighbour claims cannabis made him schizophrenic, but Swim knows it was a trigger. Swim knows quite a few with this condition, and the numbers who smoke weed are the same as Swims who are not that way. Many who were tokers continue to toke. Many Schizophrenics are actually dipping into a jar full of drugs other than cannabis. Alcohol is almost ALWAYS there in the mix with schizophrenics. More so than cannabis. The alcohol industry has enough muscle to influence studies and make sure that many users are kept in the dark as to the dark secrets alcohol has on the small print.

    Few drugs could make a sane man literally murder someone, on the spot, out of rage.

    Few murders involve potheads listening to too much rock music and deciding to go all Charlie Manson on the locals. Beer is there in most murders. Go read the statistics.

    That said, I must make it clear that most with the condition are not violent. The grim statistics prove this to be so with the only violence often being against themselves. Swim knew someone who did this. He was kind, gentle, talented but had the illness in the early 80s when nobody really understood it much. It was still hidden away which made it all so much worse.

    Swim is convinced part of the illness of schizophrenia is genetic with environmental and social factors being part of the general mix.

    Diet has made a difference to people with mental conditions.

    Swim knows many people who live alone and maybe do not get out much. Hardly going to help is it? I mean, if you have schizophrenia and nobody to go out with, maybe we can argue that being (feeling) alone in a world of 6 billions souls is wrong and we're all to blame, depending on how much we help others in that boat.

    Cannabis IS harmful, mainly because people smoke it. You smoke cannabis pure or with tobacco then its not going to be healthy in the long run. Not using a filter? Foolish really if your a daily toker.

    But blaming cannabis for everything from little dick syndrome to madness itself is laughable. Swim knows a fair few tokers and cannot say he has noticed they are any worse or better than the many drinkers Swim works with.

    Hope someone with the condition itself can maybe give their ten pence worth on this matter.

    Good luck to anyone battling it.
  5. chillinwill
  6. ihavequestions
    Re: Doubt cast on cannabis, schizophrenia link

    swim doesnt now what to beleive anymore. there are so many new articles contradicting eachother. some say there is no link, and some say there is a link. either way both sides conclude that there evidence is still not enough to realy prove anything at all. it only SUGGESTS whatever it is they are trying to prove.

    either way no one can form an opinion without total doubt
  7. Makesmefeelbig
    The problem with finding a conclusive answer to this question is that everyone has some sort of vested moral interest in the outcome- and each time a study is released, those who oppose its results will disregard it. SWIM has even been told a few times that "pot rots your brain" when he tried to explain to an anti-drugs person that the cigarettes he smoked were a lot more harmful than the weed SWIM smoked.
    This goes to show that people believe whatever they choose to believe when it comes to an issue as morally charged as this one.
  8. staples
    I have to agree with this. The study that these news articles are talking about is in the archive. There's a difference between denying something and not supporting it; in the conclusion of the paper they even suggest a possible explanation for the decline in cases of schizophrenia even if cannabis use does indeed have a causal link:
    It seems irresponsible to me to hold this research in such high regard, but then to jump the gun when the research, itself, wasn't so confident. I don't know if cannabis is god's gift to man, the epitome of drug abuse, or something in between. Regardless of its medical potential, I think it is very disturbing how the subject of cannabis has the potential to turn so many people into impetuous dilettantes who suddenly promote prevarications, citing research that they probably didn't even read or fully understand. Forget all the claims of risk or non-risk to personal health, clearly cannabis has an outstanding social effect; I certainly hope it takes more conclusive research to suggest decriminalization.
  9. ColDog
    I'd just like to say that from personal experience cannabis played a vital role, more than any other drug I use/used in me developing schizophrenia. It was the one drug I could never control what was going on in me mind and although I totally get that it's not the same for everyone, more and more shrinks are comming to the conclusion that schizophrenia is a genetic brain disease and that weed plays a vital part as a trigger that sets of a schizophrenic episode. Whether I would of developed it if I didn't smoke I will never know but personally I think yes but weed made it so so so much.
  10. Nature Boy
    I wonder why someone in your position would continue to use cannabis despite noticing an escalation in schizophrenic symptoms. Apologies if this seems blunt, but I don't feel sympathetic. It's not as if cannabis is physically addictive. It's not as if anyone forced you to smoke it. I don't think the isolated incidence of irresponsible drug use should have an effect on public policy in regards to civil liberties. If that were the case, alcohol, tobacco and nearly all pharmaceutical drugs (you could even stretch it to sugar and salt) would have to be outlawed completely. Drugs carry certain dangers and it is up to the individual to be alert to this. You can't expect the government to protect you from everything.
  11. ColDog

    I agree and I haven't used cannabis in about 8 years. Also your clearly don't know much about schizophrenia because if you did you would know that about 99% of people going through their first schizophrenic episode don't know their schizophrenic. To give an example..... If someone was to turn around to you tommorow and say that your brother or sister was infact a figment for your imagination would you believe them???? This is exactly how real a schizophrenic episode and your saying that we should be able to know that these things are in our head!!!

    You clearly don't read very much science literature either because the links between cannabis and mental health issues are widely accepted.

    You clearly don't read posts either because I never once said I think cannabis should be outlawed. In-fact I think the exact opposite, people should have the right, regardless of what any government/person say to do whatever they want to their own bodies. As long as there is no harmful effects to others then each to their own.
  12. drug-bot
    its proof of bullshit propaganda from reading this forum it seems as though the schizophrenic-mariuana link is only being spread in britian (& mabey some other small euro countrys), cause here in the usa there no news report suggesting a link between schizophrenia and mariujana or propaganda tv ads suggestng one (in fact about 11 state have decriminalized the use of marijuana, including swims state, and a number of other states have medcal marijuana progams). so its clearly cultural, if there was such a link swim would think the usa the biggest 'war' on drugs country wold be spreadng the info like wild-fire.
  13. Nature Boy
    Clearly. Tell me this then, how many schizophrenic episodes did it take before you stopped smoking? The analogy you give puzzles me. I've known my siblings for decades so it's plainly obvious that they're not figments of my imagination. Are you suggesting that you hallucinated to the point where you invented imaginary brothers and sisters? How long would this have taken? Why would someone else not notice it? I'm guessing that's not what you mean exactly but presently, I can't attach any sense to what you're saying. Please elaborate. I'm aware that schizophrenia can creep up on people but the example you've given seems entirely unfeasible. Had you imagined a new person in your life, fair enough, but you know brothers and sisters for years. I'm not going to start imagining an eldest brother in his mid-30s tomorrow. Wouldn't that be a bit of a plot hole? Hmm, brother. Funny you should walk in the door right now. I don't recall ever conversing with, or even seeing you, for the past twenty-three years of my life. Maybe I was glued to the TV or something.

    Clearly. Have you read any of this thread? The whole point is that these links are highly contentious. To claim that they're widely accepted is ridiculous considering that this is the hot topic we're dealing with right now. Fact is that they're not widely accepted. Sure, there are correlations but correlations do not equate causations. There is an endless number of possible reasons as to why people suffer mental health breakdowns. This can range from genetic conditions to cultural backgrounds to environmental structures to other substance abuse to the stress of modern life to existential crises and so on and so on. Without empirical evidence, something that troubles the assessment of mental health in general, it's all just speculation. Cannabis is a paradoxical drug that produces different effects in different people. It can be deemed a mental health stabilizer just as much as it can be deemed a mental health destabilizer. It's merely common sense that those who adapt well to it can continue use. I consider it massively irresponsible to continue use if it only results in huddling in the corner, a big bag of nerves.

    Clearly. As I said, drugs carry certain dangers and it is up to the individual to be alert to this. Using drugs as a scapegoat only heightens the sort of mass hysteria we see splattered all over the tabloids. Again, there is an endless number of reasons for mental illness. Speculating is pointless and serves ignorant lynch mobs to sharpen their knives and salivate at the mouth in anticipation of further driving something they dislike into the ground. Whimpering about what your decision to smoke cannabis and pretty-much blaming it for your mental illness is extremely short-sighted of you. Fuck, it's right up there with global Jewish conspiracies, Illuminati, alien intervention, the George Bush lizard people heirarchy. Unfounded assumptions with unfounded evidence. Mental illness is a vast tapestry. To simplify it to CANNABIS + ME = WOOP WOOP WOOP WOOP...etc. is childish.
  14. ColDog
    Fair play I used the wrong example but my point still stands that a person usually does not know they are having a schizophrenic break as it is just as real as you and me debating now so to say I was irresponsible to continue my drugs use during my first break is a bit naive because until I was diagnosed schizophrenic I whole heartedly believed that everything I was going through was real. It didn't even cross my mind that I could be imaging it all. I never knew that sort of thing was possible, which I suppose might of made me a bit naive but I was only 17 so..........

    I think we are going to have to agree to dissagree about what the concensus is regards to the link between cannabis and mental health issues. From personal experience and from what I've read the link is quiet clearly there so it all depends on what material you read I suppose.

    If you read my intial post you'll see at the end I say that I say I think I would have developed schizophrenia regardless of whether I was using drugs or not because like you said there are many non drug related reasons why people develope mental health issues so I don't know what your justifying you last paragraph on. I have never have and never will use drugs as a scapegoat, what I actually said was that cannabis only made matters worse so regardless of what you say I know 100% from PERSONAL EXPERIENCE that cannabis certainly had is part to play in the serverity of MY frist schizophrenic break.

    I'm assuming SWIU smoke's weed so of course your going to defend it but what I was doing intially was just giving my personal experience, nothing more nothing less. I never said weed should be banned, even if the link was medical established. People should be able to do anything to their own bodies regardless of what anyone else says.
  15. dyingtomorrow
    A favorite government propaganda trick is to make a lie up bashing something (or serving some other goal), and then repeat it so loudly and frequently that even when it is disproven later, half the people just go on believing the lie anyways.

    "Saddam Hussein ordered 9/11 ..."

    "Obama is not a U.S. citizen ..."

    "Marijuana causes schizophrenia ..."
  16. Amnesia
    A little off topic but SWIM feels the need to say, when someone is going through a true delusional episode they do not know it. That’s the point; they believe it to be reality. Even those with previous experience of psychosis (delusions, hallucinations, thought disorder) can easily slip back into these states and still not know they have become delusional again.
    Those with experience from previous episodes may notice it beginning, the strangeness of their thoughts as an episode begins, but by the time it is in full swing a patient genuinely could believe just about anything.

    SWIM knows of a patient who believed he was married, had been for 14 years, was still married and could provide a rather in-depth – albeit fragmentary – background for her and their relationship. If the plot-holes were pointed out to him he simply failed to see the hole, not intentionally, he just didn’t understand that people thought what he was saying was out of the ordinary. The patient had never been married.
    Another example is a patient who believed he had discovered some years previously that he was related to the royal family. When asked why a member of the royal family would be working in a pub he failed to see a problem with it; he said it made perfect sense because he wanted to make his own way in the world, especially as he was illegitimate and had to put himself forward only when the queen died to avoid exposure. He believed that if he was discovered all of the paperwork that proved his heritage would be destroyed and he would not be able to substantiate his claim. He didn’t even notice the contradiction that was; by telling everyone, he was exposing himself (if it had been true).

    A true delusional psychotic episode is reality to the sufferer.

    Schizophrenia is a very misunderstood condition, especially by the general public, and the media love to hype up any violent attacks if they were carried out by someone with a serious mental health problem. 2/3 of the UK public believe all people with serious mental health problems are dangerously insane and violent.
    SWIM can't think of many other illnesses that a government could claim a substances causes in order to scare the crap out of people who don't know any better.

  17. Nature Boy
    Fair enough. I suppose I just want to reiterate the notion that we can't actually know for sure what triggers schizophrenia because the nature of mental illness is so mysterious. There's no blood test or tissue sample that can be done and brain scans only show activity levels, not the source. Perhaps cannabis, combined with many other factors, can trigger it in a small portion of the population but so can alcohol, stress, the wrong pharmaceuticals etc. I don't like seeing "cannabis = schizophrenia" becoming one of these commonly accepted urban myths. It may cause anxiety in some people but mere anxiety isn't schizophrenia. It's a lot more complex than that as you have rightly pointed out. We all get carried away with ideas that seem to fit. A recent study from the Czech Republic concluded that heavy beer drinkers showed no marked increase in stomach size. The data seems pretty solid. But people refuse to accept this seemingly radical new idea because they associate the infamous "beer belly" with that bloated feeling one has after drinking a fizzy brew. They're probably also reluctant to accept the idea that "beer" bellies come from a mixture of bad diet, genetics and lack of excercise. Beer becomes the scapegoat, a lot like how cannabis has become the scapegoat when discussing mental illness. A good dose of personal responsibility shouldn't be written off.
  18. ColDog

    Cool cool...... My personal opinion is that it can cause mental health issues but is it the sole reason for schizophrenia or bi-polar etc, no and like you said in one of your previous posts we can't go around as a society banning everything that could cause problems otherwise we would have to ban cigs, booze etc. Also there's so much miss information out there you don't really know where to base your opinions on know what I mean. It was only a few decades ago that the government was putting out advertisment warnings that cannabis makes you want to kill people???? Lol. And it's not just weed either, esctacy was used by doctors for patients that had terminal illnesses to help them cope with the idea of death until they worked there way into the club scene. The list is endless....... Saying all of that though drugs should never be underestimated and gone into lightly, although they can be a positive to your life they also can be very destructive know what I mean. Anyway rant over...............
  19. Finn Mac Cool
    My younger brother started smoking cannabis when he was in his early 20's, after a period of a few months he was locked down in a mental hospital and over the next two months diagnosed with schizophrenia. The doctors told him it is likely the cannabis (strong skunk) was the catalyst. I think it was always there, laying dormant and I wonder if he hadn't of started cannabis would he have got past his 20's and not be schizophrenic.
  20. Nature Boy
    No point dwelling on the ifs. What if he had gotten married, had kids and then had his breakdown? There are always worse scenarios. Strong skunk though? The weed that makes it's way into this country is generally quite weak. Vacuum-packed low-to-mid grade strains for the most part. Hell, SWIM wishes he had some "strong skunk" right now. To him, the words "skunk", "liberal", "atheist", "sceptical" and "critical" are not dirty words.
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