schizophrenia - cannabis - psychosis

I note that at Carol Platt Liebau

"a New York Times piece about a study showing that long-term heavy use of marijuana slows both the mind and the body. As if we hadn't already guessed . ."

Earlier I posted Sunday, January 08, 2006 on Health Crisis - schizophrenia - cannabis
Cannabis is worst drug for psychosis - theaustralian.news.com.au - Simon Kearney
November 21, 2005 - Four out of five people with incurable schizophrenia smoked cannabis regularly between the ages of 12 and 21.
Andrew Campbell, of the NSW Mental Health Review Tribunal, warned that a hidden epidemic of cannabis-induced psychosis could make the so-called soft drug more dangerous than heroin.
And also:
Studies link cannabis use to psychosis in teenagers - smh.com.au January 28, 2006
Evidence is mounting that heavy marijuana use can increase the chances of developing severe mental illness for some adolescents whose genes put them at added risk.
The link between cannabis and psychosis gained ground this week when two influential medical journals reviewed the research to date and concluded it was persuasive.
In PLoS Medicine, Professor Wayne Hall, a public health policy expert at the University of Queensland, wrote that genetically vulnerable teenagers who smoke marijuana more than once a week "appear at greater risk of psychosis". An article in the British medical journal BMJ cited estimates that marijuana could contribute to about 10 per cent of psychosis cases.