King’s College London Causes Psychosis (with anti-marijuana propaganda)
Psychosis is a state of aberrant salience in which faulty perceptions (hallucinations) and faulty beliefs (delusions) combine to produce problematic behaviour. Many researchers around the world are studying this phenomena to try to alleviate it, but at least one faculty is pretending to study it in order to engineer a panic about a plant which psychotic patients often find to be extremely useful, but which it is politically expedient to blame. Psychosis Studies at King’s College London has released numerous studies which betray fundamental failures of understanding regarding the condition in their faculty’s title, especially the role of negative symptoms in psychotic disorders such as schizophrenia. It is hard to be sympathetic towards these failures, when their interpretations combine wilful use of stigmatising language, misdirection and exaggeration to try to disprove the fact that their patients sometimes use tobacco and marijuana because they find them to be helpful, and to “prove” on the contrary that these plants are the cause of the harms in question, using studies incapable of showing causation. In this article I will review just three such studies, although their other material is riddled with the same problems.
Let’s start with a study in which they contradicted themselves in their own abstract, displaying a shocking lack of willingness to listen to their patients or honestly consider their reasons for use:
Kolliakou A, Castle D, Sallis H, Joseph C, O’Conner J, Wiffen B, Gayer-Anderson C, McQueen G, Taylor H, Bonaccorso S, Gaughran F, Smith S, Greenwood K, Murray R, Di Forti M, Atakan Z, Ismail K. 2015. “Reasons for cannabis use in first-episode psychosis: Does strength of endorsement change over 12 months?” European Psychiatry 30(1): 152-159
To excerpt from the abstract: “At each time-point, patients endorsed ‘enhancement’ followed by ‘coping with unpleasant affect’ and ‘social motive’ more highly for their cannabis use than any other reason… Little support for the self-medication or alleviation of dysphoria models was found. Rather, patients rated ‘enhancement’ most highly for their cannabis use”
Positive psychotic symptoms do not occur in a vacuum, but are associated with negative symptoms, which generally precede by years the onset of first episode psychosis. Negative symptoms consist of absences, such as cognitive impairment, anhedonia or lack of motivation. These are primary sources of suffering for people with psychotic disorders, and arguably constitute “the core of the disorder,” at least if that disorder is schizophrenia. Relief from negative symptoms — enhancement, coping with unpleasant affect, etc — is therefore extremely important, and it’s ridiculous to say that patients’ endorsements for enhancement do not support self-medication. What they found was that their patients find cannabis to alleviate the core symptoms of their condition; what they reported was that self-medication can be rejected, on the basis of which we are to conclude that the relative increase in use among prodromal schizophrenics is proof that marijuana use causes schizophrenia, a hypothesis for which there is a mountain of countervailing evidence they do not consider.
Now let’s look at their work which compares users who prefer relatively stimulating, high THC marijuana over relatively relaxing formulations such as hash:
Di Forti M, Marconi A, Carra E, Fraietta S, Trotta A, Bonomo M, Bianconi F, Gardner-Sood P, O’Conner J, Russo M, Stilo S, Marques T, Mondelli V, Dazzan P, Pariante C, David A, Gaughran F, Atakan Z, Iyegbe C, Powell J, Morgan C, Lynskey M, Murray R. 2015. “Proportion of patients in south London with first-episode psychosis attributable to use of high potency cannabis: a case control study” S2215-0366(14)00117-5
Although their sample showed no association between cannabis use and psychosis, they dichotomised the cannabis users into “skunk using” and “hash using” groups — using the term “skunk” to refer to relatively more stimulating bud (not to a specific strain), apparently only because that’s easier to stigmatise, since “skunk” sounds worse than, say, “girl scout cookies” — and showed that the rate of psychosis was somewhat higher in the “skunk using” group. As above, they reject self medication on the basis that THC does not alleviate positive symptoms of psychosis, while ignoring that it DOES alleviate NEGATIVE symptoms of psychotic disorders. They say: “That people who already have prodromal symptoms would choose a type of cannabis that is high in THC and has little cannabidiol (such as skunk), which might exacerbate their symptoms, rather than a cannabidiol-containing type (such as hash), would seem counterintuitive” — this is only counterintuitive if you completely ignore negative symptoms, and the fact that THC alleviates them. This would be more forgiveable if they hadn’t also published studies in which they had interviewed schizophrenics who TOLD them why they use it. Just to break it down really simply: people suffering from negative symptoms enjoy and value THC because it is stimulating, not because it is relaxing. You can’t in good faith reject “self medication” while ignoring self-medication for the symptoms that are actually the greatest source of suffering in the patients’ lives and only focusing on other symptoms for which, it’s true, THC is not effective, and can even exacerbate (while some people with psychotic symptoms value marijuana, others stay away from it; it makes it worse for some and helps for others). It’s not “counterintuitive” that people in a prodromal period — those for whom positive symptoms are not yet overwhelming — prefer stimulating cannabis over relaxing cannabis. I would accuse Psychosis Studies at King’s College London of incompetence, but their use of the stigmatising term “skunk,” combined with this flagrant disregard for the well being of their patients has eroded all my sympathy for them, and so instead I’ll just call them corrupt, shameful propagandists actively hurting the public by manipulating data to create undue concern. At that, they are not incompetent, but apparently quite adept.
and now the new study that came out this week:
Rigucci S, Marques T, Di Forti M, Taylor H, Dell’Acqua F, Mondelli V, Bonaccorso S, Simmons A, David A, Girardi P, Pariante C, Murray R, Dazzan P. 2015. “Effect of high-potency cannabis on corpus callosum microstructure” Psychological Medicine Published online November 27 2015
As in the above study, they dichotomised users with a preference for stimulating cannabis from users with a preference for relaxing cannabis, and looked for evidence of differences in brain structure between the groups, finding a very small difference in the corpus callosum. That is, users with a preference for stimulating cannabis have 2% thinner corpus callosa than users with a preference for relaxing cannabis. The difference is too small to realistically consider as damage, and the study cannot show causation, but it’s assumed that any difference at all must be proof of harm, and so causation is assumed. The title even says “effect of high-potency cannabis on corpus callosum microstructure,” despite no evidence that this was an “effect of high-potency cannabis,” as opposed to an effect of a slightly thinner corpus callosum making users more likely to prefer relatively stimulating forms of cannabis, or some form of confounding (for example, they did not control for childhood trauma, which is known both to damage the corpus callosum and to greatly increase the rate of marijuana dependence among its survivors).
“Since high-potency preparations are now replacing traditional herbal drugs in many European countries, raising awareness about the risks of high-potency cannabis is crucial.”
Setting aside the fact that cannabis IS a traditional herbal drug, listed in every pharmacopoeia ever written (excluding those pressured to exclude it during the war on drugs), claiming their finding as a “risk of high potency cannabis” is indefensible. There is no scientific justification for their position. Prematurely claiming harm simply because you found — in a small, badly controlled study –that a small difference in one area correlates with one preference as opposed to another will only raise alarm, and make people who are not at risk think they are at risk, or even to create risk where it wasn’t previously by promoting nocebo effects, and inevitably iatrogenic harm.
The faculty of Psychosis Studies at King’s College London is encouraging harmful delusions, to the detriment of everybody. Since we are at a moment of redefining laws governing access to this plant, raising awareness about the actual reasons why people use it, and its actual effects, is crucial. Ignorant and inflammatory anti-marijuana propaganda of this ilk should no longer be tolerated. If psychosis researchers don’t understand what negative symptoms are or why the stimulating effects of THC might be relevant to them, they should have no business writing about the “effects of high potency cannabis” while displaying a name so prestigious as King’s College. If King’s College would like to retain its prestigious status, and not be associated with this sort of indefensible nonsense, this faculty should be defunded immediately.
Studies showing corpus callosum damage in childhood trauma survivors:
Studies showing that marijuana alleviates negative symptoms: