By: Jennifer Hong, NewsOXY Reporter
07/25/2010 07:45 AM ET
Complex link marijuana psychotic disorder, schizophrenia. A recent health study found a complex link between psychotic disorders, such as schizophrenia, and marijuana use. It is a well-known fact that marijuana can cause short-term psychotic experiences, such as hallucinations and paranoia, even in healthy people.
However, for a long time now researchers have noted a link between marijuana use and the chronic psychotic disorder, schizophrenia. Many studies have concluded that people who smoke pot are almost twice as likely to develop schizophrenia as those who do not. In 2007 a widely published review of the research concluded that trying marijuana just once was associated with a 40 percent increase in risk of schizophrenia and other psychotic disorders.
On the contrary, more recent studies have shown conflicting results. A recent study used 100 patients between the ages of 16 and 40 with schizophrenia half of whom smoked marijuana. The lead on this study was Dr. Serge Sevy, an associate professor of psychiatry at the Albert Einstein College of Medicine in New York City. Sevy and colleagues found that among the marijuana users, 75 percent had begun smoking before the onset of schizophrenia and that their disease appeared about two years earlier than in those who did not use the drug. However, when the researchers controlled for other factors known to influence schizophrenia risk, including gender, education and socioeconomic status, the association between disease onset and marijuana disappeared.
Gender alone accounted for a large proportion of the risk of early onset in Sevy's study. The subjects consisted of 69 men and 31 women. "Males in general have earlier age of onset of schizophrenia," Sevy said in a statement. In men, the disease tends to take hold around age 19, while in women it isn't typically seen until 22, irrespective of marijuana use. However, typically teenage boys are four times more likely than girls to be heavy pot smokers, which may create an illusory association between the drug and onset of the disease.