Latest Research On Cannabis and Schizophrenia Runs Contrary to Mainstream Media Hype
http://blog.norml.org/2010/05/26/la...renia-runs-contrary-to-mainstream-media-hype/
The mainstream media loves to spill ink hyping the allegation that cannabis 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 cannabis use “demonstrated significantly better performance on measures of processing speed, verbal fluency, and verbal learning and memory” compared to abstainers. cannabis 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 cannabis 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.
study:
Are cannabis use disorders associated with an earlier age at onset of psychosis? A study in first episode schizophrenia.
Sevy S, Robinson DG, Napolitano B, Patel RC, Gunduz-Bruce H, Miller R, McCormack J, Lorell BS, Kane J.
The Zucker Hillside Hospital of the North Shore Long Island Jewish Health System, Psychiatry Research, USA; Albert Einstein College of Medicine, Department of Psychiatry, USA.
Also:
http://medicalmarijuana.procon.org/view.answers.php?questionID=000220
Does marijuana use cause lasting schizophrenia, psychosis, or other mental disorders?
Colin Blakemore, PhD, ScD, Chair of the Department of Physiology at the University of Oxford, wrote in a Dec. 27, 2002 email to ProCon.org:
"It is conceivable that excessive use of cannabis sometimes contributes to acute schizophrenic episodes. But it is difficult to believe that cannabis is a strong risk factor for this disorder, because there is no evidence that the incidence of schizophrenia has risen dramatically over the past 50 years, in parallel with the huge increase in cannabis use.
Young schizophrenic patients are often heavy cigarette smokers too, but no-one would suggest that tobacco causes schizophrenia."
Paul Armentano, Senior Policy Analyst at the National Organization for the Reform of Marijuana Laws (NORML), stated in an Aug. 2, 2007 press release titled "NORML Responds to New Rash of Pot and Mental Health Claims":
"Despite the enormous popularity of cannabis in the 1960s and 1970s in numerous Western cultures, rates of psychotic disorders haven't increased since then in any of these societies. Individuals suffering from mental illness such as schizophrenia tend to use all intoxicants - particularly alcohol and tobacco - at greater rates than the general population. Not surprisingly, many of these individuals also use cannabis."
Lynn Zimmer, PhD, late Professor Emeritus at the Queens College, noted in her 1997 book Marijuana Myths, Marijuana Facts:
"Given that the incidence of schizophrenia declined substantially in Western societies in the 1970s, at the same time cannabis use was rising, it seems highly unlikely that marijuana causes schizophrenia in otherwise healthy people....
Cannabis psychosis is self-limiting, disappearing in a few days with or without medical treatment. Toxic psychosis probably occurs more commonly in individuals with preexisting psychiatric disorders....
Marijuana temporarily alters mood, thought, emotions, and perception, sometimes quite dramatically. None of marijuana's effects cause people to behave in any particular manner.
In the midst of a toxic psychosis, people may become agitated and frightened. In response to acute panic, people may become withdrawn and inactive.
Neither of these states eliminates the social and moral restraints that guide human behavior."