Pubdate: Mon, 13 Dec 2004
Source: Sydney Morning Herald (Australia)
Copyright: 2004 The Sydney Morning Herald
Contact:  http://www.smh.com.au/
Details: http://www.mapinc.org/media/441
Author: Jock Cheetham

PUFF AND THE TRAGIC DEMONS

Marijuana retains its image of peace and love, despite growing evidence it
can unleash severe mental torment - especially among the young. Jock
Cheetham assesses the case for a change of mind.

Dave's sister worried when he began spending days staring at the backyard.
He saw faces in the trees, but she saw nothing. And Dave got angry because
the family couldn't see the faces. "I felt like God was talking to me," Dave
says. "You know, showing me signs like the clouds in the shape of a peace
sign, the faces in the trees, the way the trees used to dance to the music
in my head."

Dave, 22, has smoked cannabis since he was 16. He has also used ecstasy. His
story fits a disturbing profile. Australians are smoking more - the number
of 20-year-olds who have smoked cannabis has trebled in 30 years, the
Australian Institute of Health and Welfare says. And Australians are
starting younger - nearly 40 per cent of those born in the early 1980s had
smoked cannabis by the time they reached 16.

Rates of anxiety and depression among young people have risen markedly in
each of the past five decades, the Mental Health Council of Australia says.
But for some parents who grew up during and since the counter-culture
generation, cannabis continues to symbolise freedom, rebellion and
broadminded perspectives. Their views are often based on out-of-date
information, says Ian Hickie, a professor of psychiatry at the University of
Sydney.

"The social discussion has really been downplayed by people of my generation
- - middle-aged people who've grown up where smoking cannabis has been an
important part of the culture," says Hickie, a board member of the Mental
Health Council of Australia. "They have this idea that cannabis is just like
alcohol and is our preferred substance of use. It hasn't hurt us so much, so
why are we worried."

Two of Hickie's concerns relate to mental illness - depression and the
increase in diagnoses of drug-induced psychosis. "Basically, anyone who
turns up with a schizophrenia-like illness and they're smoking cannabis and
they're taking ecstasy, the first few times we see them, we call [it]
drug-induced psychosis," he says. "But if you follow people up, the great
majority of them turn out to have schizophrenia, but later on." This lag
until the appearance of schizophrenia could be 10 years or more, he says.

The symptoms are disturbing, Hickie says. "Kids who are psychotic have
symptoms such as social withdrawal and are not able to form relationships.
Typically people will hear voices, they will develop suspicious ideas, they
won't trust their family, they'll withdraw from social events, they'll often
become quite apathetic."

Dave's illness - diagnosed as drug-induced psychosis - has turned the
middle-class family from Sydney's inner west upside down. "We've had
comments about how we look different," says Dave's mother, "and how we are
in ourselves. It's the hardest thing I've ever had to deal with in my life.
And the screaming, the screaming. One night Dave was going off and we were
holding the door trying to stop him going out. He has a very abrupt manner,
which he never used to be like."

She cries as she confesses her guilt over feeling that she neglected her
daughter during her HSC year because the family was focused on Dave, who has
been hospitalised four times in two years during psychotic episodes. "At the
time he went to hospital, his thoughts were very jumbled," she says. "He's
not able to put things into perspective."

His father says: "He thought he was either Jesus Christ or a messenger."

"Prophet!" Dave cuts in.

"A prophet of God," his father says. "And he had to save the world. That was
his main trip that he was on. He thought he was going to die."

Dave's father says he feels like he's aged 10 years in the past two. "Dave
has become very introverted," he says. "We just want him to be like he was.
It put a big strain on our [the parents'] relationship too. There were more
arguments in the house, before we knew what was going on. I'd always try to
pacify and it used to blow up in my face."

Dave left his job in late 2002 and he stopped going to university. He has
not worked solidly since. He sold his television, and then began selling
everything he owned to buy cannabis. He has stolen from his parents.

A NEW study from Maastricht University in the Netherlands has added to the
evidence of links between cannabis and psychosis. The study of 2400 young
Germans, published two weeks ago in the British Medical Journal, found
"exposure to cannabis during adolescence and young adulthood increases the
risk of psychotic symptoms later in life". The risk is even greater, the
researchers say, for people who are predisposed to psychotic symptoms.

One of the Maastricht research team, Cecile Henquet, told the Herald: "If
you have a family history or a personal history of mental instability you
should not use cannabis." Smoking cannabis before the age of 16 carries a
much higher risk of psychotic disorders and the risk rises the more
frequently the drug is used.

The Maastricht study conforms with other findings, says Professor David
Castle, of the University of Melbourne and the Mental Health Research
Institute. "We're finding that more and more of the associations between
cannabis and later mental illness, especially psychotic disorders, are being
replicated. It's more difficult to say it's one study and one finding and
dismiss it."

Once the psychotic episodes have begun, though, the consequences can be
severe and long lasting, Hickie says. "Untreated psychotic episodes can go
on for six or 12 months. Stopping drugs is an essential part of managing
these conditions, if you can."

But stopping drugs may not be enough to end the psychosis, because they have
"precipitated an autonomous brain process, and you've got to treat that
brain process".

Previously researchers thought that brain development finished by 16 or 17.
But modern brain imaging techniques reveal development continues - mainly in
the frontal lobes - at least until the early 20s, Hickie says.

The frontal lobes are important in the development of reasoning, developing
more sophisticated judgements, understanding of social interactions, and of
planning - the higher cognitive functions.

"It's a continuing process," says Hickie. "The earlier the exposure to drugs
that may in some way interfere with that process, the more likely it is
there'll be harm.

"So the cognitive or emotional changes that precede the onset of psychosis
are often happening in 13-, 14-, 15-year-olds. It's absolutely a gradient.
The longer you can delay exposure, the less likely it is there will be harm
from that exposure. In a public information sense that means emphasising
strategies to delay exposure."

The risks are greater because young people are starting to smoke cannabis
very young now, says Castle, who edited a recently released book, Marijuana
and Madness. "First of all you've got a longer period of exposure. You've
also got the situation where you might escalate your use or move on to other
drugs.

"If you're impairing those sorts of functions at a critical stage in your
intellectual development, i.e., in your teens, when you're setting the
template for the rest of your life, you can land up on a very slippery
slope.

"Because you're losing that window of opportunity in your teens to develop a
whole lot of skills, learn a whole lot of information, get the educational
platform that will allow you to go on to higher education, those sorts of
things. You never get it back."

Castle and Hickie cite the work of a team led by Professor George Patton, of
Victoria's Centre for Adolescent Health, which has linked regular cannabis
smoking to depression. The study, also published in the British Medical
Journal, found weekly cannabis use in teenagers "predicted an approximately
two-fold increase in the risk for later depression and anxiety".

And the study found that "the prevalence of depression and anxiety increased
with higher extents of cannabis use, but this pattern was clearest in female
participants".

The Melbourne study also challenged the popular hypothesis that people with
anxiety or depression self-medicated with cannabis. Not all studies have
replicated these findings, and the academics believe more study is needed to
confirm the links.

Nonetheless, the rates of anxiety and depression among young people have
gone up markedly each decade in the past 50 years, Hickie says. So each
generation has higher rates of anxiety and depression than the one before,
and also higher rates of substance use.

"That doesn't prove that drugs are the cause," he says. "But one of the hot
debates is whether the patterns of substance abuse have driven up the rates
of anxiety and depression. And if that were the case you'd see exactly what
we're seeing."

Unfortunately, many people are not fully aware of their family's history of
mental illness. Dave's father believed his family had no history of mental
illness. But on reflection he recalls that one of Dave's grandmothers and a
great-aunt had committed suicide.

These factors were enough to suggest the likelihood of mental illness in the
family, says Professor Wayne Hall, of the University of Queensland. In this
situation, "I would say don't smoke cannabis, and I would caution about
alcohol use, because that's another potent contributor to suicide in people
with psychiatric illness".

Dave who, like his family spoke on the condition of anonymity, has stopped
smoking frequently this last month. And his delusions have declined since he
was prescribed lithium in hospital, his father says. He has been offered a
full-time job in his chosen field after more than two years without regular
work, and the family is more stable and looking positively towards the
future.

Drug-induced school drop-outs

Research has shown that daily use of cannabis in adolescence, particularly
early use, predicts a lot more poor outcomes for development than just the
established links with psychosis, says Professor Wayne Hall, of University
of Queensland.

So Hall finds disturbing the trend of younger use over the decades, the
increase in heavy use, and the use of bongs (water pipes) for joints because
they deliver more THC (tetrahydrocannabinol), the main active constituent.
Hall estimates people's chances of psychosis increase from one in 100 to
about one in 50 with heavy use of marijuana.

Hall says there is a greater incidence of general social problems among the
heavy users - about 7 per cent of young people.

Among the problems they are more likely to encounter than non-users are poor
school performance, early school drop-out, possibly increased risk of
depression and poorer mental health, probably some increased risk of
anti-social behaviour and probably some increased risk of ending up in the
criminal justice system, says Hall, who has worked on cannabis research for
11 years and is co-author of Cannabis Use and Dependence. 
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