Ebony
05-12-04, 12:52 PM
Cannabis linked to mental illness risk
Sarah Boseley, health editor
Thursday December 2, 2004
The Guardian (http://www.guardian.co.uk/)
Some young people who smoke cannabis are at real risk of developing psychotic mental illness, according to a major study announced yesterday.
The new survey of 2,500 young people aged 14 to 24 will be discussed at the start of an international conference today on cannabis and mental health convened by the Institute of Psychiatry in London.
It shows that regular cannabis smoking increased the risk of developing psychosis by 6% over four years.
But there was a substantially greater impact on young people who had already been identified by psychiatrists as having the potential to become psychotic. Regular cannabis smoking raised their risk of developing psychotic mental illness by 25%.
The study aimed to answer a question that has been unsettling psychiatrists for some time. People with psychosis, whose symptoms include hallucinations, paranoia, hearing voices and a persecution complex, are more likely than not to have a marijuana habit.
But doctors have not known whether they are smoking it for relief from their symptoms, or whether cannabis itself might be the problem.
Cannabis may be a harmless recreational drug for most of its users and has medicinal benefits for others, but the study will add fuel to the debate on its legalisation. One of the authors of the study, carried out by researchers from the Netherlands, said that although cannabis triggered psychosis in a minority of people, this was a good reason to legalise it, not ban it, so that government can promote advice and information, as it does on alcohol.
Jim van Os, a professor in the department of psychiatry and neuropsychology at Maastricht University in the Netherlands, where cannabis is legal, said a ban would be hard. "It is going to be very difficult to tell the whole Dutch population to stop using cannabis because it is bad and you will develop psychotic illness. But perhaps it is better to say if you have a family history or mental instability you are perhaps particularly at risk of negative consequences of cannabis use.
"The way to get the message across is for young people to talk about the issues and have more social control among themselves, rather than the big brother approach."
Zerrin Atakan, honorary senior lecturer at the national psychosis unit of the Institute of Psychiatry and a speaker at today's conference, said cannabis had medicinal uses and, like alcohol, was not a problem in moderation. She pointed to the different effect on the brain of the two compounds it contained - tetrahydrocannabinol (THC) and cannabidiol (CBD). Cannabis high in THC was stronger and potentially more dangerous, while CBD might be responsible for its beneficial effects.
"I personally believe it should be legalised so it is tightly regulated and it says on the packet how much THC is in it," she said. "At the moment it is worse because people think it is legalised and there is confusion and it is in the hands of the dealers. That is not a good situation."
The study, published in the online version of the British Medical Journal, followed 2,437 young people living in Munich, Germany.
All had a psychiatric assessment at the start of the study, to identify those who might be vulnerable to psychosis. Four years later, they were asked about their cannabis use and their mental health was assessed again. Regular users of cannabis who had been identified as vulnerable to psychosis were much more likely to become psychotic than those who were neither. Robin Murray, professor of psychiatry at the Institute of Psychiatry, London, said there were still many unanswered questions, such as: "If half the world smokes cannabis, why aren't they all psychotic?"</FONT>
http://society.guardian.co.uk/mentalhealth/story/0,8150,1364454,00.html
Sarah Boseley, health editor
Thursday December 2, 2004
The Guardian (http://www.guardian.co.uk/)
Some young people who smoke cannabis are at real risk of developing psychotic mental illness, according to a major study announced yesterday.
The new survey of 2,500 young people aged 14 to 24 will be discussed at the start of an international conference today on cannabis and mental health convened by the Institute of Psychiatry in London.
It shows that regular cannabis smoking increased the risk of developing psychosis by 6% over four years.
But there was a substantially greater impact on young people who had already been identified by psychiatrists as having the potential to become psychotic. Regular cannabis smoking raised their risk of developing psychotic mental illness by 25%.
The study aimed to answer a question that has been unsettling psychiatrists for some time. People with psychosis, whose symptoms include hallucinations, paranoia, hearing voices and a persecution complex, are more likely than not to have a marijuana habit.
But doctors have not known whether they are smoking it for relief from their symptoms, or whether cannabis itself might be the problem.
Cannabis may be a harmless recreational drug for most of its users and has medicinal benefits for others, but the study will add fuel to the debate on its legalisation. One of the authors of the study, carried out by researchers from the Netherlands, said that although cannabis triggered psychosis in a minority of people, this was a good reason to legalise it, not ban it, so that government can promote advice and information, as it does on alcohol.
Jim van Os, a professor in the department of psychiatry and neuropsychology at Maastricht University in the Netherlands, where cannabis is legal, said a ban would be hard. "It is going to be very difficult to tell the whole Dutch population to stop using cannabis because it is bad and you will develop psychotic illness. But perhaps it is better to say if you have a family history or mental instability you are perhaps particularly at risk of negative consequences of cannabis use.
"The way to get the message across is for young people to talk about the issues and have more social control among themselves, rather than the big brother approach."
Zerrin Atakan, honorary senior lecturer at the national psychosis unit of the Institute of Psychiatry and a speaker at today's conference, said cannabis had medicinal uses and, like alcohol, was not a problem in moderation. She pointed to the different effect on the brain of the two compounds it contained - tetrahydrocannabinol (THC) and cannabidiol (CBD). Cannabis high in THC was stronger and potentially more dangerous, while CBD might be responsible for its beneficial effects.
"I personally believe it should be legalised so it is tightly regulated and it says on the packet how much THC is in it," she said. "At the moment it is worse because people think it is legalised and there is confusion and it is in the hands of the dealers. That is not a good situation."
The study, published in the online version of the British Medical Journal, followed 2,437 young people living in Munich, Germany.
All had a psychiatric assessment at the start of the study, to identify those who might be vulnerable to psychosis. Four years later, they were asked about their cannabis use and their mental health was assessed again. Regular users of cannabis who had been identified as vulnerable to psychosis were much more likely to become psychotic than those who were neither. Robin Murray, professor of psychiatry at the Institute of Psychiatry, London, said there were still many unanswered questions, such as: "If half the world smokes cannabis, why aren't they all psychotic?"</FONT>
http://society.guardian.co.uk/mentalhealth/story/0,8150,1364454,00.html