Dr. Mitch Earleywine Ph.D. responds to latest “marijuana causes early psychoses” claim

Easily the coolest college professor you could ever hope to have.

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.” (more…)

Latest Research On Pot and Schizophrenia Runs Contrary to Mainstream Media Hype

The mainstream media loves to spill ink hyping the allegation that marijuana causes mental illness, particularly schizophrenia. In fact, it was in March when international media outlets declared that cannabis use ‘doubled’ one’s risk of developing the disease. Yet when research appears in scientific journals rebuking just this sort of ‘reefer madness,’ it generally goes unreported.

Such is the case with a pair of just-published studies slated to appear in the journal Schizophrenia Research. The first study, conducted by a team of researchers at various New York state hospitals, the Yale University School of Medicine, and the National Institutes of Mental Health assessed whether there exists a causal association between cannabis use and the age of onset of psychosis in patients hospitalized for the first time for an episode of schizophrenia.

Despite previous media claims to the contrary, researchers concluded:
“Although the onset of cannabis use disorder preceded the onset of illness in most patients, our findings suggest that age at onset of psychosis was not associated with cannabis use disorders. Previous studies implicating cannabis use disorders in schizophrenia may need to more comprehensively assess the relationship between cannabis use disorders and schizophrenia, and take into account the additional variables that we found associated with cannabis use disorders.”

A separate study slated for publication in the same journal assessed the cognitive skills of schizophrenic patients with a history of cannabis use compared to non-users. Authors reported that patients with a history of marijuana use “demonstrated significantly better performance on measures of processing speed, verbal fluency, and verbal learning and memory” compared to abstainers. Marijuana use was also associated with better overall GAF (Global Assessment of Functioning) scores compared to those of non-users.

Authors concluded: “The results of the present analysis suggest that (cannabis use) in patients with SZ (schizophrenia) is associated with better performance on measures of processing speed and verbal skills. These data are consistent with prior reports indicating that SZ patients with a history of CUD (cannabis use disorders) have less severe cognitive deficits than SZ patients without comorbid CUD. … The present findings also suggest that CUD in patients with SZ may not differentially affect the severity of illness as measured by clinical symptomatology.”

Both study’s findings are in line with previous (though virtually unreported) research indicating that marijuana is unlikely to instigate incidences of schizophrenia in the general population, that cannabis use among patients with the disease is associated with higher cognitive function, and that at least some schizophrenics find subjective relief from symptoms of the illness by using pot. Nonetheless, odds are the nobody from the mainstream media will be champing at the bit to report on them.

Bottom line: marijuana’s complex relationship with schizophrenia is far from understood, and likely won’t be for some time. But that doesn’t give the MSM a free pass to only promote one side of the story.

Weeding Through The Hype: Interpreting The Latest Warnings About Pot and Schizophrenia

Once again members of the mainstream media are running wild with the notion that marijuana use causes schizophrenia and psychosis.

To add insult to injury, this latest dose of reefer rhetoric comes only days after investigators in the United Kingdom reported in the prestigious scientific journal Addiction that the available evidence in support of this theory is “neither very new, nor by normal criteria, particularly compelling.” (Predictably, the conclusions of that study went all together unnoticed by the mainstream press.)

Yet today’s latest alarmist report, like those studies touting similar claims before it, fails to account for the following: If, as the authors of this latest study suggest, cannabis use is a cause of mental illness (and schizophrenia in particular), then why have diagnosed incidences of schizophrenia not paralleled rising trends in cannabis use over time?

In fact, it was only in September when investigators at the Keele University Medical School in Britain smashed the pot = schizophrenia theory to smithereens. Writing in the journal Schizophrenia Research, the team compared trends in marijuana use and incidences of schizophrenia in the United Kingdom from 1996 to 2005. Researchers reported that the “incidence and prevalence of schizophrenia and psychoses were either stable or declining” during this period, even the use of cannabis among the general population was rising.

That said, none of this is to suggest that there may not be some association between marijuana use and certain psychiatric ailments. Cannabis use can correlate with mental illness for many reasons. People often turn to cannabis to alleviate the symptoms of distress. One study performed in Germany showed that cannabis offsets certain cognitive declines in schizophrenic patients. Another study demonstrated that psychotic symptoms predict later use of cannabis, suggesting that people might turn to the plant for help rather than become ill after use.

Of course, even if one takes the MSM’s latest ‘sky is falling’ scenario at face value, health risks connected with pot use — when scientifically documented — should not be seen as legitimate reasons for criminal prohibition, but instead, as reasons for the plant’s legal regulation.

For instance, as I told AOL News earlier today: “We don’t outlaw peanuts because a small percentage of people have allergic reactions. We educate the community, we regulate where and when peanuts can be exchanged. That seems like it ought to apply to marijuana, too.”

To draw another real world comparison, millions of Americans safely use ibuprofen as an effective pain reliever. However, among a minority of the population who suffer from liver and kidney problems, ibuprofen presents a legitimate and substantial health risk. However, this fact no more calls for the criminalization of ibuprofen among adults than do these latest anti-pot allegations, even if true, call for the current prohibition of cannabis.

Placed in this context, today’s warnings latest do little to advance the government’s position in favor of tightening prohibition, and provide ample ammunition to wage for its repeal.

Supposed Marijuana And Schizophrenia Link “Overstated”

[Editor's note: This post is excerpted from this week's forthcoming NORML weekly media advisory. To have NORML's media advisories delivered straight to your in-box, sign up for NORML's free e-zine here.]

Clinical evidence indicating that marijuana use may be casually linked to incidences of schizophrenia or other psychological harms is not compelling, according to a scientific review published online by the journal Addiction.

Investigators at the University of Bristol, Department of Social Medicine assessed the potential health risks of cannabis, particularly whether use of the drug may be causally linked with mental illness.

Authors wrote: “We continue to take the view that the evidence that cannabis use causes schizophrenia is neither very new, nor by normal criteria, particularly compelling. … For example, our recent modeling suggests that we would need to prevent between 3000 and 5000 cases of heavy cannabis use among young men and women to prevent one case of schizophrenia, and that four or five times more young people would need to avoid light cannabis use to prevent a single schizophrenia case. … We conclude that the strongest evidence of a possible causal relation between cannabis use and schizophrenia emerged more than 20 years ago and that the strength of more recent evidence may have been overstated.”

In 2007, an analysis in the British medical journal The Lancet estimated that experimenting with marijuana could increase one’s risk of developing a psychotic illness later in life by some 40 percent. Following this report, Parliament in 2008 voted to reclassify marijuana as a Class B substance, making its possession punishable by up to five years in prison.

University of Bristol researchers also criticized Parliament’s reclassification of the drug, which took effect earlier this year. They concluded: “The only important possible benefit of prohibition is prevention of cannabis use. There is little or no evidence that it effectively achieves this benefit. Patterns of cannabis use in the population appear to be independent of the policy surrounding use, and criminalizing individual cannabis users does not appear to modify their use in a healthy way.”

Overall, investigators determined that marijuana’s most significant health risk was its association and reinforcement with tobacco smoking.

Canadian Broadcasting Corp: “Doubt Cast on Cannabis, Schizophrenia Link”

Well, better late than never.

Doubt cast on cannabis, schizophrenia link
via CBC

A British study has cast doubt on the supposed link between cannabis use and schizophrenia.

… This latest study, led by Dr. Martin Frisher of Keele University, examined the records of 600,000 patients aged between 16 and 44.

… Frisher and colleagues compared the trends of cannabis use with general practitioner records of schizophrenia and psychosis.

They argue that if cannabis use does cause schizophrenia, an increase in cannabis use should be followed by an increase in the incidence of schizophrenia.

According to the study, cannabis use in the United Kingdom between 1972 and 2002 has increased four-fold in the general population, and 18-fold among under-18s.

Based on the literature supporting the link, the authors argue that this should be followed by an increase in schizophrenia incidence of 29 per cent between 1990 and 2010.

But the researchers found no increase in the rates of schizophrenia and psychosis diagnosis during that period. In fact, some of the data suggested the incidence of these conditions had decreased.

Over the past few years the mainstream media, as well as federal politicians, have enjoyed promoting the notion that smoking pot induces mental illness. Perhaps most notably, in 2007 the MSM touted that cannabis “could boost the risk of developing a psychotic illness later in life by about 40 percent” — a talking point that was also publicly promoted US anti-drug officials. Similarly, Canadian bureaucrats alleged — just two weeks ago — that marijuana users have a “seven-fold increase” in risk of developing schizophrenia.

Given this environment, I held little hope that anyone in the MSM would bother to report on the Keele University study — which initially appeared online on the website of the journal Schizophrenia Research in late June and was reported on by NORML on July 2 — despite its obvious newsworthiness.

And for nearly two months no one did. But kudos to the Australian Broadcasting Corporation and a handful of British tabloids for just now bringing these findings to light (and even acknowledging that the MSM would have arguably provided far more prominence to this story had the findings demonstrated the opposite result.)

For now, let’s score one for the good guys, and cross your fingers that the American press will also eventually take notice.