All Party Parliamentary Group on Mental Health

1^st March 2005

Meeting to discuss Cannabis and Mental Health

Marcus Roberts, Head of Policy, DrugScope

Mr Roberts began by noting that the Home Office reclassified cannabis from Class B status to Class C on 29^th January 2004. He mentioned that he had been invited to speak to “balance” the debate but wanted to clarify that the mental health and drugs worlds were not in conflict over this issue, rather that they spoke from different perspectives. Mr Roberts said that one could support reclassification whilst being concerned about the link between mental illness and cannabis. He explained that DrugScope is an evidence-based organisation. He said that reclassification was not a denial that cannabis can be harmful as all controlled drugs are dangerous but that the level of harm was different. The debate needs to be balanced to acknowledge the problems caused for a small minority of users. A Home Office survey in 2002 showed that the social and economic costs of heroin were far higher than those relating to cannabis.

Mr Roberts outlined two arguments supporting reclassification:

·         The Government’s decision was based on three thorough and independent reviews.

·         The social and economic costs to society of Class B status for cannabis were very high in terms of policing and the criminalisation of young people who would probably grow out of using cannabis anyway.

The Home Office has seen a reduction in police time spent on cannabis users since reclassification whilst continuing to be tough on the supply and trafficking of the drug. Research has also shown that young people have a good knowledge of the drug laws and know that cannabis remains illegal. The debate around cannabis and mental health has grown since reclassification but this is because several pieces of research have been published since that time.

Mr Roberts finished by calling for greater education and information about the risks associated with cannabis use.

Professor Robin Murray, Institute of Psychiatry

Prof. Murray noted that though three reviews had been carried out before the reclassification was approved, only one survey linking mental illness to cannabis had been published when the decision was made. Since then several important studies have been published.

Prof. Murray observed that reclassification had been accompanied by the message that cannabis was harmless however it has been known for 50years that taking large quantities can cause brief psychotic episodes. It has also been known for a long time that cannabis affects memory and concentration. A study in Jamaica in the 1960s linked psychosis with cannabis but there was still an attitude that people with schizophrenia could smoke cannabis to make them feel better. A study in Holland then revealed that the opposite was the case. In 1987 a Swedish study following 50,000 army recruits showed that those who used cannabis were far more likely to develop psychosis. In 2002 a birth cohort study in New Zealand showed that people who used cannabis by the age of 15yrs were 4.5 times more likely to develop psychosis than their contemporaries. Many other studies have been conducted since then including another New Zealand study published on 1^st March 2005.

Prof. Murray concluded that some people are more prone to developing psychosis than others and for these people cannabis can be a contributing factor. Starting to smoke cannabis earlier (during teenage years) is far more risky than starting later in life.

John Foxwell, Carer

Mr Foxwell spoke from personal experience about his 20yr old son. His son was a bright boy with many friends. When he was 15yrs old his behaviour changed, he became lethargic, gradually lost all his friends, spent a lot of time on his own and his schoolwork deteriorated. His short-term memory was affected and he found it impossible to retain new information. Mr Foxwell didn’t initially recognise these changes as signals of cannabis smoking until he heard a school friend refer to his son as a “dope head”. His son has since revealed that in their village it was easier for under-16yr olds to buy cannabis than to buy cigarettes. Mr Foxwell noted that teenagers smoked cannabis far more heavily than people had done in the 1960s and also use stronger varieties of the drug.

Mr Foxwell struggled to get a GP to recognise that there was a problem but eventually his son was referred to a psychiatrist who diagnosed schizophrenia.

The illness affected Mr Foxwell’s son in many ways. He couldn’t fill out forms or write a CV and so couldn’t get work. His siblings felt annoyed and ignored. He couldn’t be left alone outside of the family home. He also still smokes occasionally and this aggravates his condition. He also has periods of paranoia and at times has been aggressive, he was once sectioned. He is now 20yrs old and does work for three hours a day.

Q&A

The session was then opened up to the floor. Lord Turnberg thanked Mr Foxwell for his touching story and asked whether he had noticed any improvement in his son’s condition when he is not smoking cannabis. Mr Foxwell said that he is much better when not smoking cannabis but he still smokes occasionally with friends.

Lord Turnberg also asked whether there is a risk of schizophrenia if a person takes up smoking cannabis at a later stage in life. Prof. Murray responded that there is still a risk if a person starts smoking in the 20s or 30s but the risk is higher during the teenage years as the brain is still developing. Lynne Jones noted that most people who develop schizophrenia do so during their late teens and early twenties regardless of whether they smoke cannabis. Prof. Murray stated that the average age for men to develop schizophrenia is 23 and for women, 28. Drug consumption is also higher among males than females.

Lynne Jones asked whether there was an acceptable level of smoking below which there was no risk. Prof. Murray said that even smoking a couple of times a week for 6 months could cause problems especially if strong cannabis is being smoked.

Baroness Murphy asked whether Afro-Caribbean communities had a particular problem with schizophrenia which could be linked to cannabis use.  Prof. Murray noted that Afro-Caribbean people are six times more likely than white people to be diagnosed with schizophrenia but that this does not relate entirely to cannabis use as white people now smoke as much.

Baroness Masham asked whether there was any physical reaction to cannabis. Prof. Murray said that the Home Office has denied there being any risk but that it was clearly linked to respiratory problems. Mr Foxwell added that when people smoke using bongs the smoke is very hot which is damaging to the lungs. Also as tobacco is used there are the usual problems associated with cigarette smoking. Mr Roberts added that smoking cannabis when young can lead to a lifetime of smoking cigarettes.

An observer who works as an Approved Social Worker noted that many people do not disclose that they use cannabis when they talk to health professionals and that more sophisticated campaigns are needed.

Joan Penrose(carer) said that her son had started using cannabis at the age of 35 and changed enormously, he now has schizophrenia as does her other son. She asked whether he would recover from schizophrenia if he stopped smoking or whether he would always have it. Prof. Murray said that people should avoid smoking cannabis if they have a relative with schizophrenia, as they are likely to be more vulnerable. He noted that people can recover from schizophrenia.

Dr Freeman (Royal College of Psychiatrists) noted that there are similarities with the debate around alcohol, it is culturally acceptable and the risks are largely ignored. Prof. Murray said that the epidemiology was similar. However he noted that the use amongst young people was heavier than use of alcohol with many uder-16 yr olds smoking every night. If cannabis was legalised it probably wouldn’t be legal under-16. He also noted that the drinks lobby is very powerful and if cannabis was legal there would also be a very strong lobby for cannabis.

Lynne Jones asked whether there was any information from Holland. Dr Alison Lowe (addictions psychiatrist) said that the Government there had decreased the amount people could buy and was not licensing new cafes.

Mr Foxwell noted that there were leaflets in schools with information about cannabis but none of them stated that cannabis could cause long term problems. Dr Lowe said that heroin and crack were much more of a problem for addiction services and that it would be wrong to demonise those who smoke cannabis. She said that cannabis use is cultural and many people find that it helps them in terms of sociability and it may make them feel better. People need to be taught how to balance the risks involved with taking drugs and their own vulnerabilities. She also noted that dual diagnosis does not fit into Government targets and therefore is badly served by the health service.

Laura Johnson (carer, Rethink) said that she had set up a support group largely for those with schizophrenia and their carers. They have anecdotal evidence linking cannabis use with the development of schizophrenia in people who have then gone on to find out that there is a family history of the disease. Her group has produced leaflets and distributed them to local schools with information about the risks. She noted that the Government’s FRANK campaign is good in general but doesn’t mention schizophrenia.

Dr Herietta Bowden-Jones (addictions psychiatrist) reported that she is writing a leaflet for the Royal College of Psychiatrists on the link and that it would be made public on the College’s website.

Mr Roberts noted that the Home Office and Department of Health have different priorities and that the crime reduction agenda drives Home Office policy. Prof. Murray agreed with this. Dr Lowe added that healthcare professionals need better training in substance misuse issues but at the moment their training in this are is being decreased.

Lynne Jones thanked the speakers and requested that the note of the meeting be sent to Caroline Flint MP at the Home Office requesting a response to some of the concerns raised particularly regarding the information available to young people on the harmful effects of cannabis.

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