186°
Well-Known Member
(I renamed the thread. The first version should imitate click bait, wasn't happy with it)
from a famous german talk show:
Dr. Guest*: “There are some beautiful studies that show that if young people between the ages of 15 and 16 smoke weed just five times, they have a three-fold increased risk of developing psychosis by the age of 30.”
Host: (asks with interest) “How much? A…”
Dr. Guest: “A threefold increased risk.”
Host: “Three times higher!”
Dr. Guest: (nods meaningfully)
Host: “And you don’t want that. That’s catastrophic. Because of five times!”
No, of course we don't want that...
So, let's say, someone around you claims that the use of cannabis leads to a high(er) risk of psychosis. You, much like me, would like to know whether this is really true. You want to know what the science says but on the one hand you don't have the expertise in this field to check by yourself and on the other hand you are, honestly said, deeply biased in the hope that the psychosis claim isn't true. I got you covered! Or better said not me, but a blog post by a professor who took the scaremongering on a TV show as an opportunity to take a closer look at the state of science and comments on the reliability of the data and significance of the studies.
Here's the link to the blog post: https://scilogs.spektrum.de/mensche...a-grassnickel-und-markus-lanz-im-faktencheck/
It is in german. Worth a read anyway and way shorter than the cited scientific articles + some really nice comments. Just use your browser to translate it; I checked the translation side by side and it was an almost nicer read than the german version
Don't skip the introductory part where he describes the scene in the TV show. It is a somehow funny beginning and just a typical example of someone misinterpreting scientific conclusions regarding cannabis to mislead a public debate.
In short/tldr:
What? The science isn't clear on the question whether cannabis increases the risks of psychosis. It just ins't clear (at the moment).
Who said that? I got this from a blog post by Stephan Schleim. Associate Professor for theory and history of psychology at University Groningen (Netherlands).
Where is it published? It's a long running blog about popular scientific topics on https://scilogs.spektrum.de, which belongs to Spektrum science magazine which belongs to Springer Nature publishing group, publisher of many high ranking scientific journals, like, you know, "Nature". However, it is a blog post, not a peer-reviewed paper.
How does he know?
He's not an expert on this specific topic. His scientific work seems to be a lot about how science works and how knowledge is presented and generated (that's what makes his perspective so interesting IMO). In this case he looked closer at two "beautiful" Scandinavian studies which were wrongly cited in a TV show and turn out to be not so beautiful after all regarding the claims made in the TV show. But mostly his conclusion is based on a review paper of 2019:
Farris, M.S., Shakeel, M.K. & Addington, J. Cannabis use in individuals at clinical high-risk for psychosis: a comprehensive review. Soc Psychiatry Psychiatr Epidemiol 55, 527–537 (2020). https://doi.org/10.1007/s00127-019-01810-x
This is the real peer-reviewed scientific overview – not just a blog post. For Details. You can cite it.
Objective of the Farris et al. study:
Review to understand prevalence of cannabis use and how it is associated "with transition to psychosis, symptoms, cognition, trauma and family history in clinical high risk (CHR) for psychosis individuals."
The review concludes:
"However, cannabis use has not been thoroughly researched regarding frequency and dose of use, and how other factors, such as symptoms, are associated with cannabis in CHR individuals."
Stephan Schleim's conclusion with focus on political decision making:
"To conclude our study with a sensible thought: In a discussion like this, legalization should not be compared with the utopia (or rather dystopia?) of abstinence. Rather, the current situation must be used for comparison. The correct question is therefore not whether cannabis consumption increases the risk of psychosis; the correct question is only whether (partial) legalization leads to more or fewer psychoses. The studies cited here say nothing about this."
*on a sidenote: As if the reality presented in TV wasn't absurd enough the guest's name is Dr. Graßnickel which basically translates to Dr. Weednickel
. She is now head physician at a private clinic for psychiatry, psychotherapy and psychosomatics. Her focus is on psychiatry and addiction medicine.
from a famous german talk show:
Dr. Guest*: “There are some beautiful studies that show that if young people between the ages of 15 and 16 smoke weed just five times, they have a three-fold increased risk of developing psychosis by the age of 30.”
Host: (asks with interest) “How much? A…”
Dr. Guest: “A threefold increased risk.”
Host: “Three times higher!”
Dr. Guest: (nods meaningfully)
Host: “And you don’t want that. That’s catastrophic. Because of five times!”
No, of course we don't want that...
So, let's say, someone around you claims that the use of cannabis leads to a high(er) risk of psychosis. You, much like me, would like to know whether this is really true. You want to know what the science says but on the one hand you don't have the expertise in this field to check by yourself and on the other hand you are, honestly said, deeply biased in the hope that the psychosis claim isn't true. I got you covered! Or better said not me, but a blog post by a professor who took the scaremongering on a TV show as an opportunity to take a closer look at the state of science and comments on the reliability of the data and significance of the studies.
Here's the link to the blog post: https://scilogs.spektrum.de/mensche...a-grassnickel-und-markus-lanz-im-faktencheck/
It is in german. Worth a read anyway and way shorter than the cited scientific articles + some really nice comments. Just use your browser to translate it; I checked the translation side by side and it was an almost nicer read than the german version
Don't skip the introductory part where he describes the scene in the TV show. It is a somehow funny beginning and just a typical example of someone misinterpreting scientific conclusions regarding cannabis to mislead a public debate.
In short/tldr:
What? The science isn't clear on the question whether cannabis increases the risks of psychosis. It just ins't clear (at the moment).
Who said that? I got this from a blog post by Stephan Schleim. Associate Professor for theory and history of psychology at University Groningen (Netherlands).
Where is it published? It's a long running blog about popular scientific topics on https://scilogs.spektrum.de, which belongs to Spektrum science magazine which belongs to Springer Nature publishing group, publisher of many high ranking scientific journals, like, you know, "Nature". However, it is a blog post, not a peer-reviewed paper.
How does he know?
He's not an expert on this specific topic. His scientific work seems to be a lot about how science works and how knowledge is presented and generated (that's what makes his perspective so interesting IMO). In this case he looked closer at two "beautiful" Scandinavian studies which were wrongly cited in a TV show and turn out to be not so beautiful after all regarding the claims made in the TV show. But mostly his conclusion is based on a review paper of 2019:
Farris, M.S., Shakeel, M.K. & Addington, J. Cannabis use in individuals at clinical high-risk for psychosis: a comprehensive review. Soc Psychiatry Psychiatr Epidemiol 55, 527–537 (2020). https://doi.org/10.1007/s00127-019-01810-x
This is the real peer-reviewed scientific overview – not just a blog post. For Details. You can cite it.
Objective of the Farris et al. study:
Review to understand prevalence of cannabis use and how it is associated "with transition to psychosis, symptoms, cognition, trauma and family history in clinical high risk (CHR) for psychosis individuals."
The review concludes:
"However, cannabis use has not been thoroughly researched regarding frequency and dose of use, and how other factors, such as symptoms, are associated with cannabis in CHR individuals."
Stephan Schleim's conclusion with focus on political decision making:
"To conclude our study with a sensible thought: In a discussion like this, legalization should not be compared with the utopia (or rather dystopia?) of abstinence. Rather, the current situation must be used for comparison. The correct question is therefore not whether cannabis consumption increases the risk of psychosis; the correct question is only whether (partial) legalization leads to more or fewer psychoses. The studies cited here say nothing about this."
*on a sidenote: As if the reality presented in TV wasn't absurd enough the guest's name is Dr. Graßnickel which basically translates to Dr. Weednickel
. She is now head physician at a private clinic for psychiatry, psychotherapy and psychosomatics. Her focus is on psychiatry and addiction medicine.
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