Skunk pot increases risk of psychosis & schizophrenia

It's lack of balance that makes skunk cannabis do harm

26 January 2010 by Amanda Feilding and Paul Morrison
Magazine issue 2744.

For similar stories, visit the Comment and Analysis , Mental Health and Drugs and Alcohol Topic Guides
THE effects of cannabis on mental health have attracted much attention over the years. As far back as the 19th century it was recognised that cannabis could induce a transient psychosis which mimics the symptoms of schizophrenia. Despite this, until the last decade or so, most psychiatrists regarded cannabis as essentially benign.

This, however, is at odds with recent research which concludes that in a susceptible minority, cannabis use can push the brain towards long-term psychosis requiring mental health treatment. Susceptible young people who use cannabis increase their risk of developing a chronic psychotic disorder such as schizophrenia, and the more cannabis they consume, the higher the risk.

Additionally, people with schizophrenia who have a history of cannabis use tend to go through their first breakdown up to five years earlier in life than those who do not use the drug. Psychotic patients who fail to give up cannabis experience more symptoms, more relapses and end up in hospital more often.

http://goo.gl/CUI8

And in probably a larger group

WTF?

:shrug:

Did you get that point?

I really get sick and tired of seeing propaganda like this. If you can't be honest, you have no point to make.

I'm not making a point - just passing along information.

Use it or ignore it.

It's lies.

not you...

This research was carried out by Dr Marta Di Forti and colleagues from the Institute of Psychiatry, King’s College, London. The study was funded by the Maudsley Charitable Fund, and a grant from the National Institute of Health Research in the UK. The study was published in the peer-reviewed medical journal, The British Journal of Psychiatry.

http://goo.gl/an2t

You should follow your own leads.

What you're describing doesn't make sense. Are you saying they pay dividends to the U.K. government?

Link please.

If you have evidence that this "evil" charity has compromised the study or is making money through the back door based on the findings - please post it.

Thinking that cannabis hastens a psychotic break is seriously in error.

I've known too many people in the early stages of the illness who sought it out to help calm the terror of a mind out of control.

They're self medicating. They're not hastening the inevitable.

It has been repackaged and republished about dozens of times a year for the last 4 or 5 years.

It's pure bullshit no matter how many times it's released.

For those who dismissed the OP without reading the full article...

So-called "skunk" does contain higher than normal concentrations of the main psychoactive compound, a molecule called delta-9-tetrahydrocannabinol (THC). What is less well known is that another constituent, cannabidiol (CBD), has been eliminated from skunk through selective breeding to increase the THC content.

The elimination of CBD may play a key role in the development of psychosis. Laboratory studies have shown that pure, synthetic THC causes transient psychosis in 40 to 50 per cent of healthy people. In stark contrast to THC, CBD appears to have an anti-psychotic effect, at least in animals. Studies in humans, though few in number, have produced similar findings.

Skunk #1 usually has higher THC content than average, but it still has CBD's like all strains. This particular strain is called "UK Cheese", which is just one phenotype of Skunk #1. It's strong and stinky, but not CBD free.

It's just Cannabis, not crack or meth.

I am a medical marijuana grower in Ca. This article is total BS.

It's propaganda, nothing more.

This research was carried out by Dr Marta Di Forti and colleagues from the Institute of Psychiatry, King’s College, London. The study was funded by the Maudsley Charitable Fund, and a grant from the National Institute of Health Research in the UK. The study was published in the peer-reviewed medical journal, The British Journal of Psychiatry.

http://goo.gl/an2t

It's propaganda.

You are in denial.

They have a dog in this race, no question.

It's in their best interest to show the weed as evil...

then you can use that against any study that finds negative data about cannabis.

You believe that a non-profit charitable organization WANTED the data to be negative to increase their rehab recruitment so they could use that as a tool to solicit donations so they could keep their jobs? Is that the logic? Wow - talk about cynical.

How would a study have to be structured for you to believe the data?

With no tentacles to the industry in question.

I find it rather naive to think that ALL charitable institutions are lily white and free from sin.

And conducted by who?

They pay dividends to the UK... hardly a non-profit.

Message removed by moderator. Click here to review the message board rules.

Perhaps I should have taken the time to try to educate the person spreading this blatant lie, but I felt they all ready knew they were baring falsehoods.

How is it a "non-profit" pays dividends? To the UK!

Naw... don't bother trying to educate... this one can't even get the DU rules right... see deleted message... brother!

What rule did I violate?

South London and Maudsley Charitable Funds

South London and Maudsley (SLaM) Charitable Funds are made up of donations that have been made to South London and Maudsley NHS Foundation Trust and its predecessor organisations. It is managed by the Trust's Board members, who invest in projects that support improved mental healthcare, wellbeing, infrastructure, innovative services, early-stage research projects, training and development.

The aim for the endowment is to be a key agent in enhancing mental health provision and changing how mental health is viewed - in the local community and on a wider scale.

The charitable funds supports individuals and organisations (directly linked to the SLaM NHS Foundation Trust and external parties) to drive change, help ideas turn into reality and enable others to reach their true potential.

http://maudsleycharity.com/index.html

What dividends are you referring to? Link?

geez... this drug war propaganda BS needs to be removed.

WHY do I NEVER get sick?

I mean never. I had the flu when I was 21 - 13 years ago. That's it. For my entire life. I am not lying. I get 1 -2 headaches a year. Never had a cold, never been laid up in bed. Always healthy - NEVER sick. Never had a flu shot, don't take any medicine, never taken aspirin...

Oh yeah, I like to smoke.

I think one has to do with the other...

I haven't seen any data to support the notion that cannabis boosts the immune system. On the contrary there are several studies that suggest cannabis suppresses the immune system. Those studies are controversial and are not fully supported by the medical/scientific community. As to your anecdotal evidence that pot has kept you healthy - do you take any supplements? Vitamin D? Do you spend a lot of time outside? Do you exercise regularly? Do you eat red meat or are you a vegetarian?

There can be many reasons why you don't get sick including a genetic advantage of having a strong immune system. It would be a huge leap of logic to attribute it to pot. When I was your age (34) I was not smoking pot (I quit around 25) but never got sick either. I believe the immune system is the strongest between 21-50. It starts around 21 because by that time you been exposed to most pathogens and have built up an immune response and it declines starting around 50-55 due to age.

"susceptible minority", "push the brain towards", "increase their risk","such as schizophrenia", "up to five years earlier", "fail to give up". This is all pulled straight out of someones ass. They do not in fact have any method to retroactively determine the "risk" for people who had no symptoms or history, so they cannot determine if the risk went up or not. They are treating correlation and selection effects as though they were causal.

Conclusion

This study has strengths and limitations. Among its strengths are the researchers’ careful adjustments to account for the influence of age, gender, ethnicity, other stimulant use, level of education achieved and employment status (all factors known to influence the incidence rates of psychosis). This study is also large for its kind. The size of the effect seen was also large and statistically significant.
However, because it is a case control study, it has the limitation of being unable to prove causation

It's amazing to me how DU'rs reacted to this OP. I am not against pot smoking - I used to smoke pot for years. I believe it should be legalized. I'm just posting information so people here can be informed. If I were offered a joint today I would think twice though. Pot today is at least 10X more powerful than the stuff I smoked back in 69. Even the stuff I smoked then there were times when I went a little overboard. With pot growers striving to make pot even more potent who knows where will be in 10 - 20 years. I don't understand the "more is better" mentality.

Obviously there's a lot of pot smokers here. The resistance to the study is understandable but I was hoping there would be more critical thinking here than just a short response of "bullshit" and "propaganda". I'm a newbie here and this takes some getting used to. It's at tough crowd here.

Believe me, it's not worth your time.

That's pretty much a myth. The numbers don't bear it out.

Average THC content of seized marijuana
1973 1.23%
1984 3.31%
2004 5.81%
Original Source: University of Mississippi, Marijuana Potency Monitoring Project
http://www.briancbennett.com/charts/fed-data/thc-content/thc-content-marijuana.htm (sorry, those are the most recent numbers I can find on a quick google search)

So between 1973 and 2004 that represents a 4.7X increase in THC potency. It's true that's a percent change of 9.4 (.0581-0.123/.0123) but that is much different than a ten times increase in potency. Besides, this is a myth that has been spread since at least the 1980s when I was a teen when average THC content was only 2.7 times greater than the early 1970s.

One should also note that there were only 34 samples seized in 1973 versus 939 in 2004. So we're not really able to tell if the 1.23% number is accurate. It could be much higher meaning the difference in THC levels over the two decades is even less dramatic. Of course, it could be much lower too, but that seems less likely in my opinion than it being higher. In any case, 1.23% average THC content in 1973 is the number we have to work with so its best to go with that.

As near as I can tell, this myth arose whole cloth out of the Reagan era anti-drug use propaganda.

Not that there aren't some adverse outcomes associated with marijuana use for some people. But it's very hard to separate out the propaganda (from either side of the debate) from the facts so it's good to always check the most reliable numbers we have against the claims. Usually one finds the claims simply aren't based in reality.

On edit: I agree with HuckleB. It's almost impossible to have an honest and open discussion about cannabis (or any drug use really) on DU. I'm not jumping on your case because of your OP. I'm just being pedantic about the "10X more powerful" myth.

The researchers report that the ‘skunk’ form of cannabis contains between 12% and 18% THC (the active ingredient) and less than 1.5% cannabidiol, a substance that is thought to be protective. In contrast, cannabis resin (hash) has an average THC concentration of 3.4% but a similar proportion of cannabidiol.

http://www.nhs.uk/news/2009/12December/Pages/psychosis-risk-smoking-skunk-hash-cannbis-compared.aspx

I remember smoking hash in 70 that blew me away on just a few tokes. If it was 3.4% like in the study then I can't imagine what smoking something with 12-18% THC would be like. I'll pass.

It refers to all cannabis. As we can see, at least through 2004, the average THC content is much lower than that. For the average to be around 5% then that means the majority of seized cannabis had to be closer to the ~5% average. No matter how you look at it, the "10X more powerful" myth doesn't hold water.

Once again, I'm not trying to contradict the study's findings. I'm just concerned with that one very popular myth.

Here's the latest report on THC potency produce in March '09...

http://www.whitehousedrugpolicy.gov/publications/pdf/mpmp_report_104.pdf

The average THC content is increasing steadily but as of 2008 the average THC is still only 4.8%. I'm discounting the 2009 numbers because they only report 2 seizures.

Again, I am only concerned with the "10X more powerful" myth here. I am not addressing any other issues.

Those were the "non-normalized" domestic seizures average. see table 7. Who knows how they came up with those numbers. How many of the domestic seizures were young plants that didn't have time to mature?

I have no idea what they mean by non-normalized. Maybe bemildred can explain.

On page 17, table 8 - the non-domestic non-normalized average THC for 2008 was 10.05 which is close to the 10X. That represent 70% of the pot seized.

I agree that the "pot of today has 10X the THC" etc. is a myth.

Any generalized statement like that is a myth. It all depends on what you're smoking.

I'll take a closer look at the report tomorrow since I've just had dinner and plan on relaxing the rest of the evening.

You make an excellent point though that we have no way of knowing what level of maturity the seized plants were at. That would affect the THC levels greatly.

Two quick notes:
1) Is it just me, or does it seem improbable that slightly over 70% of all seized marijuana should be imported (i.e. not domestic)
2) I seem to recall reading elsewhere that they got to the 10.05% average THC by factoring in hashish in addition to marijuana. My memory is like swiss cheese these days so please don't take that as an authoritative claim.

Thing is,no one smokes as much these days because of its increased potency.
Back in the seventies,before kind buds came out,it was common for most people to smoke several joints at one sitting in order to catch a buzz.Today,I can take just a couple of hits and I'm toast.These days,most people don't even role joints anymore.Its just a waste to do so.
Back then,I would go through one or two ounces in a week.Now a quarter ounce lasts me a week.This cutback in how much people are smoking is one of the reasons pot is so expensive these days.The dealers had to raise the prices to cover the income loss from selling less pot.

it was stronger back in the day. i have been looking for that super shit ever since st ronnie told me about it.

It does not explain the alternative interpretations of the data, the weakness of the methodology, nothing. It is fatuous to claim that they can "control" for all the things they claim to. One can infer that usage is self-reported, i.e. hearsay, and self-reporting of substance usage is notoriously inaccurate, even for people without "mental problems". It is a pile of wind. It is dishonest, it is bullshit.

The best bud runs 25% THC.
Not only can they not prove causation, they cannot even infer it, the most they can do is speculate about it, yet they do infer it anyway.
All your quote does it admit that they are pulling conclusions out of their ass.
This is not science, it is propaganda.

Just curious.

And 20+ years doing software engineering, simulations, network programming, etc. Most importantly here, I know statistics, sampling, and probability theory.

This is not a criticism but just something to ponder...

Your'e disciplined in an abstract world of bit and bytes where there's rules - everything is neatly defined. It's either true or not true. Psychology and real life are more dynamic and squiggly, more open to interpretation and opinion.

OTOH, my opinion is as good as anybodys.

The most essential point, in my view, is that one tends to find what one goes looking for, which is one of the reasons that double-blind studies in medical research are the gold standard, the other reason being that people tend to feel better or worse when given nothing, depending on what they are told.

And the fact here is that this is not a double-blind study, it's more like an opinion poll.

The essential question is why one ought to believe it, take it seriously at all, and the answer is that they should not.

and I would be happy to treat the results of such studies, if well done, as meaningful.

Were there double-blind studies when researchers determined that smoking tobacco caused lung cancer? How would that work? Have one group of people smoke a tobacco-less cigarette for 20 years then compare the results with the group that smoked real cigarettes?

The pot/psychosis study was a case control study...

Case-control study
A case-control study is an epidemiological study that is often used to identify risk factors for a medical condition. This type of study compares a group of patients who have that condition with a group of patients that do not have it, and looks back in time to see how the characteristics of the two groups differ.

http://www.nhs.uk/news/Pages/Newsglossary.aspx#Casecontrolstudy

also of interest...

Methodological Issues in Case-Control Studies: Validity and Power of Various Design/Analysis Strategies

GEOFFREY R HOWE* and BERNARD C K CHOI
* NCIC Epidemiology Unit, Faculty of Medicine, McMurrich Building, University of Toronto Toronto, Ontario, Canada M5S 1A8 (address for reprint requests)
Research student of the National Cancer Institute of Canada

Computer simulations have been used to estimate the efficiency, as measured by the statistical power, of various combinations of design and analysis strategies for case-control studies. Conditions under which the various forms of analysis yield consistent relative risk estimators are derived for the general model. The results indicate that the loss of efficiency resulting from the use of a less than optimum design or analysis strategy in many real life situations is small. Practical considerations are of more importance than theoretical statistical ones in deciding upon appropriate strategies. It is concluded that matching is rarely, if ever, justified in most case-control studies of chronic diseases.

http://ije.oxfordjournals.org/cgi/content/abstract/12/2/238

Or am I mistaken?

One problem is that whatever strategy one employs to "control" for different variables, that itself becomes a new hypothesis, that that strategy works in that particular case, which is unproven. To be even somewhat sure of ones ground, one must first provide good support for the "control" methodology in the domain of discourse. That is going to be a very complicated task in itself, if done right, so of course nobody ever does it. But if one does, then ones method of proving the control methodology becomes subject to the same considerations, so you wind up with a recursive descent, or just a big mess to put it simply. So at some point everyone starts hand-waving and talking about how it all just "makes sense".

The second problem is that organic systems are extremely complicated, and it is in fact impossible to be even somewhat sure that one has considered all of the factors that are relevant to the particular issue one is discussing without extensive and expensive experimentation.

Now I am not suggesting that one ought not study organic systems, or that studies of the sort discussed in the OP have no use at all, I am suggesting that a far larger dose of humility than is common is required to keep one from wandering off in the bushes when drawing conclusions, and that doing such studies in such a way that they mean much of anything at all is far more expensive and difficult than most people assume.

So in essence I am arguing for humility, greater diligence in experimental design, and more reserved judgement about these things. Studies like the OP seem to me to be largely in the nature of opinion polls, and to suffer from many of the same defects, particularly that one tends to find what one goes looking for.

than this sort of twaddle.

The OP was a summary of the study written by journalists at NewScientist. They did not participate in the study. Their use of "susceptible minority", "push the brain towards", "increase their risk","such as schizophrenia", "up to five years earlier", "fail to give up" are their interpretations of the results.

http://www.newscientist.com/article/mg20527446.100-its-lack-of-balance-that-makes-skunk-cannabis-do-harm.html

The other link I provided was a more detailed summary of the study published by the National Health Service...

http://www.nhs.uk/news/2009/12December/Pages/psychosis-risk-smoking-skunk-hash-cannbis-compared.aspx

The actual peer reviewed research paper published in the The British Journal of Psychiatry which details the methodology can be found here...

http://bjp.rcpsych.org/cgi/content/full/195/6/488

It costs $15 to download the study.

Maybe this will clear up the obvious confusion that saturates this discussion. I provided links and thought it was obvious what was what but a lot of posters here refused to read the full articles provided in the links before jumping to conclusions and making outrageous accusations of fraud, propaganda and such.

Hope this helps.

But thank you for your concern.

I think this article is important.

For those reacting without reading the article, this isn't so much about pot causing psychosis, it's about a particular breed of the drug in various individuals.