Pubdate: Thu, 07 Mar 2002
Source: Advertiser, The (Australia)
Copyright: 2002 News Limited
Contact:  http://www.advertiser.com.au/
Details: http://www.mapinc.org/media/1

CANNABIS 'DAMAGE'

A STUDY by a Sydney researcher has found that long-term cannabis users 
could be damaging their memory and hindering their ability to concentrate. 
The impairment did not amount to serious brain damage but could be enough 
to interfere with simple tasks like reading, studying or shopping, Nadia 
Solowij of the University of NSW said. Dr Solowij led a study by the US 
Marijuana Treatment Project Research Group which focused on patients 
seeking help for marijuana dependence in US clinics between 1997 and 2000

The study concluded that chronic heavy pot smokers displayed signs of 
cognitive impairments serious enough to affect their work, life and ability 
to learn.

"This study has found that there are long-term effects of cannabis use on 
memory and on attention, and that memory function gets worse with the 
number of years that cannabis is used," she said.

The study examined 51 people who had been using marijuana daily for an 
average 24 years and compared them to 51 shorter-term users and 33 non-users.

As part of the study, the subjects were presented with a list of 15 words 
and asked to recall them later.

"In general we found that the long-term heavy users were recalling 
approximately three words less than the non-users or shorter-term users," 
Dr Solowij said.

"We found that impairment in memory was there in the group that on average 
had used for 24 years, but we didn't find any significant difference in the 
group who had used for about ten years."

Dr Solowij said she hoped to determine whether the damage was reversible 
when she finalised follow-up studies of the subjects later this year.

Her findings sparked controversy overseas after her work was published in 
the March 6 issue of the prestigious Journal of the American Medical 
Association.

Harrison Pope of Harvard Medical School disputed the findings in an 
editorial and subsequent statements.

Dr Pope said Dr Solowij's study had failed to take into account whether the 
subjects had been taking other drugs or suffered problems like anxiety or 
depression that could also affect cognitive ability.

"The safest thing to say at this point is that the jury is still out on the 
question of whether long-term marijuana use causes lasting impairment in 
brain function," he said.

While Dr Solowij concedes the jury may be out until her follow-up tests are 
concluded, her findings add weight to the adage: they don't call it dope 
'cause it makes you smart".
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MAP posted-by: Jay Bergstrom