4 ms·

When this kind of thing has come up before ("pot causes mental illness"), IIRC it turns out more that people with schizoid disorders are self-medicating with po

When this kind of thing has come up before ("pot causes mental illness"), IIRC it turns out more that people with schizoid disorders are self-medicating with pot before getting diagnosed, rather than having taken harder drugs, alcohol, etc. The classic reversed-arrow of causation.

oceanghost 5y ago
This is the correct answer here in the same way that the prevalence of ADHD is about 2x as likely in the population of meth addicts as the general population.
cornel_io 5y ago
Worse, the "classic" studies that claim to show the connection between use and schizoid disorders claim to adjust for this, but use a method that is completely wrong, and would be expected to show the same effect for any disease where diagnosis reliability at the start is less than 100% I don't remember the exact details anymore, but more or less they claim to address causation by 1) starting with a non-schizophrenic population, 2) segmenting by marijuana use, and 3) evaluating schizophrenic status N years later. The theory is that by limiting 1) to non-schizophrenics, they've factored out the possibility that schizophrenia drives drug use rather than the other way around. Of course, most schizophrenics are not actually diagnosed until waaaay past the point where they are showing symptoms, and if you've ever known a schizophrenic who was diagnosed in college, for instance, you know that that diagnosis usually comes at the end of a long chain of subtle and not so subtle mental issues, shrink appointments, and life problems that start much earlier but don't present as full blown schizophrenia. So the whole supposed filter in 1) is complete trash, and they're probably including a lot of people who are already symptomatic, just not to a clinically diagnosable degree.
southeastern 5y ago
That could be a part of it, but there is a documented effect of marijuana "triggering" mental illness in those who are susceptible to mental illness. For a certain portion of the population marijuana use will directly lead to the onset of mental illness
- techbio 5y ago
  But aren't the scare quotes necessary to the statement? Ie. it can appear that a "trigger" is actuated, because we do not know what is happening and reach for metaphor?

oceanghost 5y ago

This is the correct answer here in the same way that the prevalence of ADHD is about 2x as likely in the population of meth addicts as the general population.

cornel_io 5y ago

Worse, the "classic" studies that claim to show the connection between use and schizoid disorders claim to adjust for this, but use a method that is completely wrong, and would be expected to show the same effect for any disease where diagnosis reliability at the start is less than 100% I don't remember the exact details anymore, but more or less they claim to address causation by 1) starting with a non-schizophrenic population, 2) segmenting by marijuana use, and 3) evaluating schizophrenic status N years later. The theory is that by limiting 1) to non-schizophrenics, they've factored out the possibility that schizophrenia drives drug use rather than the other way around. Of course, most schizophrenics are not actually diagnosed until waaaay past the point where they are showing symptoms, and if you've ever known a schizophrenic who was diagnosed in college, for instance, you know that that diagnosis usually comes at the end of a long chain of subtle and not so subtle mental issues, shrink appointments, and life problems that start much earlier but don't present as full blown schizophrenia. So the whole supposed filter in 1) is complete trash, and they're probably including a lot of people who are already symptomatic, just not to a clinically diagnosable degree.

southeastern 5y ago

That could be a part of it, but there is a documented effect of marijuana "triggering" mental illness in those who are susceptible to mental illness. For a certain portion of the population marijuana use will directly lead to the onset of mental illness

techbio 5y ago
But aren't the scare quotes necessary to the statement? Ie. it can appear that a "trigger" is actuated, because we do not know what is happening and reach for metaphor?