Pubdate: Mon, 28 Aug 2006 Source: Calgary Herald (CN AB) Copyright: 2006 Calgary Herald Contact: http://www.canada.com/calgary/calgaryherald/ Details: http://www.mapinc.org/media/66 Author: Joanne Laucius, CanWest News Service Bookmark: http://www.mapinc.org/mjcn.htm (Cannabis - Canada) SMOKING POT CAN TRIGGER MENTAL ILLNESS, STUDY SHOWS A pair of articles in the Canadian Journal of Psychiatry has resurrected the "reefer madness" argument about marijuana and its links to mental illness. Cannabis use can trigger schizophrenia in people already vulnerable to the mental illness -- and this fact should shape marijuana policy, argue two psychiatric epidemiologists in this month's journal. The link between marijuana use and schizophrenia is generally accepted in the psychiatric community. The problem is that the vulnerable population -- mostly teenagers -- generally isn't eager to absorb the message. Australian epidemiologists Louisa Degenhardt and Wayne Hall reviewed eight international studies of teens and young adults that examined the link between marijuana use and schizophrenia. They concluded that using marijuana can precipitate schizophrenia in users who have a personal or family history of schizophrenia. One 15-year study of 50,000 young people in Sweden, for example, found those who had tried marijuana by the time they were 18 were 2.4 times more likely to receive a diagnosis of schizophrenia. The Swedish researchers concluded that 13 per cent of schizophrenia cases could be averted if all cannabis use was prevented. Another study of almost 5,000 subjects in the Netherlands replicated the findings, and also found that marijuana users were more likely to be diagnosed with schizophrenia during the study's three-year follow-up period. Other studies suggested subjects who used marijuana in their early teens were more likely to be diagnosed with schizophrenia by their mid-20s. - --- MAP posted-by: Beth Wehrman