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28/08/2012
Cannabis Use In Teens Used To Link Drop In IQ
New research finds that persistent cannabis use during adolescence can cause lasting harm to a person's intelligence, attention and memory.
Researchers from the Medical Research Council (MRC) Social Genetic and Development Psychiatry Centre at King's College London's Institute of Psychiatry (IoP) collaborated with scientists from Duke University in the USA and the University of Otago in New Zealand on the study published today in Proceedings of the National Academy of Sciences. They found that individuals who started using cannabis in adolescence and used it more than once a week for years afterwards showed an average decline in IQ of 8 points when their age 13 and age 38 IQ tests were compared.
The team studied the association between persistent cannabis use and neuropsychological functioning in a group of 1,037 individuals (from the Dunedin Multidisciplinary Health and Development Study) followed from birth in 1972/1973 to age 38. Cannabis use was ascertained in interviews at ages 18, 21, 26, 32 and 38. Neuropsychological testing to assess memory, processing speed, reasoning and visual processing was conducted at age 13, before cannabis use, and again at age 38.
About 15 percent of the study group were considered persistent cannabis users and 5 percent were using cannabis more than once a week before age 18. Individuals who started using cannabis persistently during adolescence a greater decline in neuropsychological function that those who started in adulthood.
Persistent cannabis use was associated with broad impairment across five domains of neuropsychological functioning, and remained significant even after controlling for years of education and use of other drugs including alcohol. Quitting or reducing cannabis use did not fully restore neuropsychological functioning among individuals who started using cannabis in adolescence.
Professor Terrie Moffitt, lead author, who holds a dual appointment at King's and Duke said: "This work took an amazing scientific effort. We followed almost 1000 participants, we tested their mental abilities as kids before they ever tried cannabis, and we tested them again 25 years later after some participants became chronic users. Participants were frank about their substance abuse habits because they trust our confidentiality guarantee and 96% of the original participants stuck with the study from 1972 to today. It's such a special study that I'm fairly confident that cannabis is safe for over-18 brains, but risky for under-18 brains."
(CD)
Researchers from the Medical Research Council (MRC) Social Genetic and Development Psychiatry Centre at King's College London's Institute of Psychiatry (IoP) collaborated with scientists from Duke University in the USA and the University of Otago in New Zealand on the study published today in Proceedings of the National Academy of Sciences. They found that individuals who started using cannabis in adolescence and used it more than once a week for years afterwards showed an average decline in IQ of 8 points when their age 13 and age 38 IQ tests were compared.
The team studied the association between persistent cannabis use and neuropsychological functioning in a group of 1,037 individuals (from the Dunedin Multidisciplinary Health and Development Study) followed from birth in 1972/1973 to age 38. Cannabis use was ascertained in interviews at ages 18, 21, 26, 32 and 38. Neuropsychological testing to assess memory, processing speed, reasoning and visual processing was conducted at age 13, before cannabis use, and again at age 38.
About 15 percent of the study group were considered persistent cannabis users and 5 percent were using cannabis more than once a week before age 18. Individuals who started using cannabis persistently during adolescence a greater decline in neuropsychological function that those who started in adulthood.
Persistent cannabis use was associated with broad impairment across five domains of neuropsychological functioning, and remained significant even after controlling for years of education and use of other drugs including alcohol. Quitting or reducing cannabis use did not fully restore neuropsychological functioning among individuals who started using cannabis in adolescence.
Professor Terrie Moffitt, lead author, who holds a dual appointment at King's and Duke said: "This work took an amazing scientific effort. We followed almost 1000 participants, we tested their mental abilities as kids before they ever tried cannabis, and we tested them again 25 years later after some participants became chronic users. Participants were frank about their substance abuse habits because they trust our confidentiality guarantee and 96% of the original participants stuck with the study from 1972 to today. It's such a special study that I'm fairly confident that cannabis is safe for over-18 brains, but risky for under-18 brains."
(CD)
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07 May 2008
'U-Turn' As Cannabis Reclassified To Class B
Cannabis has been reclassified as a Class B drug, it has been announced today. In making her decision The Home Secretary Jacqui Smith went against the advice of The Advisory Council on the Misuse of Drugs (ACMD), which wanted to keep it a Class C drug. The council has not been overruled for 30 years.
'U-Turn' As Cannabis Reclassified To Class B
Cannabis has been reclassified as a Class B drug, it has been announced today. In making her decision The Home Secretary Jacqui Smith went against the advice of The Advisory Council on the Misuse of Drugs (ACMD), which wanted to keep it a Class C drug. The council has not been overruled for 30 years.
21 September 2009
NI Teen Drug Use 'Highest In Europe'
There's been a surprise development on drug culture. Around one in 10 children in Northern Ireland under the age of 12 have used cannabis, according to research conducted by Queen's University. The Youth Development Survey questioned 4,000 teenagers in 43 schools in Northern Ireland about drug use.
NI Teen Drug Use 'Highest In Europe'
There's been a surprise development on drug culture. Around one in 10 children in Northern Ireland under the age of 12 have used cannabis, according to research conducted by Queen's University. The Youth Development Survey questioned 4,000 teenagers in 43 schools in Northern Ireland about drug use.
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