Dr. Mitch Earleywine Ph.D. responds to latest “marijuana causes early psychoses” claim
Every Wednesday on NORML SHOW LIVE, Dr. Mitch Earleywine joins us to discuss the latest research in cannabis and to take live calls and chat questions from listeners on marijuana culture, history, medicine, and science. He is a member of the NORML Advisory Board and his research has been published in over fifty scientific journals on drugs and addiction. He is the author of Understanding Marijuana, Pot Politics, and Parents’ Guide to Marijuana, and a professor of psychology at SUNY Albany. We asked Dr. Mitch his opinions of the latest meta-analysis on cannabis and schizophrenia.
Download full interview at http://audio.norml.org/events/Dr. Mitch Earleywine – Latest Cannabis Psychoses Bunk.mp3
NORML SHOW LIVE: The headlines are out there – CNN, WebMD, NPR, every little bit of alphabet soup out there on the cable channels and the news – is trumpeting this headline, this study – Matthew Large, I believe, is the lead researcher on this – from Prince of Wales Hospital in New South Wales Australia says quote:
“It is increasingly clear that marijuana is a cause of schizophrenia and that schizophrenia caused by cannabis starts earlier than schizophrenia with other causes.”
DR. MITCH EARLEYWINE: Alas, no. There are no new data – I want to emphasize that – this is a meta-analysis, which means it takes the studies that were already out there and tries to combine them mathematically to make sense of it all. What you’re not hearing in the media is that in fact, this is probably early-onset folks self-medicating.
You can imagine somebody who is experiencing some symptoms of psychosis, particularly folks with less access to medical care, or folks who are already a little bit paranoid because of the disorder and they’re unwilling to go to a physician. They hear their friends are using cannabis and enjoying it. They do it, too, they notice some mild improvements in their symptoms, they turn to it later when they have a psychotic break. What a surprise, [the researchers] say, “they smoked cannabis first, that’s the big issue.”
What burns my ass is that this same journal a month before had another article failing to replicate this data where we find folks with a special genetic risk and if they’re heavily involved with cannabis early in life they’re more likely to develop schizophrenia. So all this malarkey about, “oh, if you’re a genetic risk then you’re really gonna get it” isn’t showing up in other data sets. The media isn’t covering that in the least.
The other finding in this big meta-analysis is that early onset of psychosis showed up for folks who were using drugs more generally – not just cannabis – and this makes much more sense pharmacologically. When you think about cocaine, amphetamine, and other drugs that work directly in the dopamine system, that’s the system that schizophrenia is all about. And what a surprise, these folks are more likely to have an early onset.
I’m concerned that the cannabis-related studies are really spurious and they’re compounded by use of amphetamines, Ritalin, Adderall, all these other stimulant drugs that people were – particularly in Australia – unwilling to fess up to, but more than willing to say they used cannabis. We’ve got a big problem here.
As we’ve seen time and again none of us want children to have access to cannabis. And the way to get that access limited is, of course, not an underground market that never cards anybody, but a taxed and regulated one, where folks that are too young to be experimenting with this and folks who have psychosis in the family can be markedly more advised and essentially educated before they even purchase the plant.
NSL: Matthew Large, this researcher here, even addressed what we just discussed about the self-medication; he said, quote:
“There is not so much evidence for the widely-held view those patients self-medicate with marijuana. Marijuana smoking almost always comes before psychosis and few patients with psychosis start smoking marijuana for the first time.”
Is this a case then where they’re just defining psychosis as their starting point of looking at these people rather than the onset of symptoms that would pre-date or pre-sage the psychosis that’s about to come?
DR. MITCH: That’s it exactly, Russ, and as we’ve mentioned in the past what often happens is they find a big record of people who’ve had psychotic breaks and then go back and see if they’ve reported cannabis earlier. But we have very poor assessments of these potential psychotic symptoms before these people used cannabis and the few studies that do do that, the measures are slightly biased against cannabis users.
I’ve pointed out in the past one of the big questionnaires for this – a schizotypal personality questionnaire – has an item that says “I use words in strange and unusual ways.” Well, sure, schizophrenics certainly do that. They make words up; that’s part of the way that you manifest the diagnosis. But we also have a whole subculture here where people are “kickin’ back with the chronic at 420.” Well, what a surprise, people who do that may say “I use words in a strange and unusual ways.” In my dataset when you drop that item out, suddenly the link between schizotypy and cannabis use disappears. I’m concerned there are comparable problems in these other datasets.
NSL: One of the things we’ve always said in these pieces with you and I talking about this is how worldwide the rates of schizophrenia and psychosis seemed to stay stable at about 1% of the population, even if that population starts smoking a whole lot of weed – if a lot of them start smoking or if they start smoking a lot of it – doesn’t matter is still stays the same.
But one of the hypotheses they have here is that, “Yeah, sure, there’s a certain 1% that are gonna get psychosis but these 1% are gonna get it earlier and then they’d have these extra two or three years of psychosis-free functioning that they would be losing out of because of their use of marijuana.”
My first thought on that is if this were the case, wouldn’t we see a lowering of the median age of psychosis onset when we have higher use of cannabis in a society?
DR. MITCH: In fact, Wayne Hall in Australia has made this same suggestion and they have yet to detect this change in the median age of first onset. But he’s suggesting that some new data are going to reveal that in the current younger cohort, this is the case. I haven’t seen those data yet and I’m a little concerned. In part we go to so much effort now to try to identify psychosis earlier that it seems like if that is the case, it may be simply that we are better at identifying psychotic disorders than we were 20 years ago, so we have this other potential confound. And as Paul [Armentano] has emphasized time and again, we do have a subset of folks who really respond well to cannabis-based medicines in controlling psychotic episodes, and I think it may be a cannabidiol issue where Project CBD may be able to help us isolate who might be helped and who might not from this.
And then, of course, that fits that self-medication hypothesis better. I feel like the critique of that self-medication that they offer in this meta-analysis is premature, in part because of how poorly we assess psychotic symptoms prior to anyone’s cannabis use.
NSL: What is the actual risk to people who have a history of mental illness or who feel they may have a certain mental illness and how they should entertain the notion of using cannabis to treat themselves?
DR. MITCH: In fact, cannabis is rarely my first choice for any of the more common mental illnesses. So we’ve talked before about depression, anxiety, and PTSD. With depression, cannabis may help a subset of folks. A number of my friends who’re in clinical practice say that the people who are using it are having more troubles in their practice. But that may be a different subset.
But my first line of defense – it really sounds corny – but kind of a bibliotherapy. Educate yourself about depression. If you have a mental health center that you appreciate, 12 weeks of good hard work, of taking a look at your own faults, how you behave during the day, the way you frame the events in your life; that can last a lifetime in the treatment of depression. And then cannabis is just to enjoy, not something you have to lean on in order to make sure you have a happy day.
With anxiety, I’ve done this both on Facebook to some of our friends and repeatedly in emails and my published work. Anxiety is one of the psychological disorders that psychology really has mastered. If folks again are willing to go see a therapist for a good couple of months and really put some effort in, you can literally tame this kind of thing and make it so anxiety is no longer debilitating, and then suddenly your cannabis again is just for fun. The idea that cannabis is actually going to help anxiety is very dose-dependent, very strain-dependent, and not the most efficient way to get at this.
PTSD, I just got those new data on that. A ton of people think that cannabis helps some of the symptoms of PTSD. I completely believe them. But compared to these exposure-based treatments – which I know are a drag – [cannabis] is not going to last a lifetime the way that that kind of treatment can, and then again cannabis is just for fun. It doesn’t have to be for medication and you’re less likely to have these lingering symptoms of the emotional numbing, the distancing from your family, or these kind of freaking-out experiences when you’re in a big crowd. And then, what a surprise, you basically worked hard for three months and kicked this disorder rather than felt like “I have to lean on cannabis for the rest of my life.”
February 9, 2011