The most reliable way to avoid cannabis-related harms is to abstain from
TORONTO, Sept. 22, 2011 /CNW/ - A new research study conducted by an
international team of experts recommends a public health approach to
cannabis—including evidence-based guidelines for lower-risk use—to
reduce the health harms that result from the use of cannabis. Led by
Dr. Benedikt Fischer, CAMH scientist and CIHR/PHAC* Chair in Applied
Public Health (Simon Fraser University, Vancouver), the study is being
published in the September/October 2011 issue of the Canadian Journal of Public Health (CJPH).
More than one in ten Canadian adults, and about one in three young
people aged 16-25, report using cannabis during the past year. Despite
the prevalence and health risks associated with cannabis use, the study
points out that Canada has not yet taken a public health approach to
address its harms, as we have with alcohol, tobacco, and even injection
"A broad-based public health approach to cannabis use would include a
prevention strategy for young people, risk reduction strategies for
at-risk users, and better access to treatment for problem users,"
explains Dr. Fischer. His latest study addresses the risk reduction
component, based on a comprehensive review of existent scientific data
identifying the preeminent cannabis use patterns and practices leading
to key health risks and harms. Based on this evidence, the study offers
guidelines on how to modify these practices and patterns at the
user-level as a public health-oriented policy tool to reduce harm.
"Misinformation about cannabis can be dangerous," Dr. Fischer explains.
For example, surveys show that many young cannabis users believe that
it is safe to drive after using cannabis, whereas recent research in
Canada shows that a significant number of traffic fatalities in young
adults are attributable to cannabis use. "This resembles the situation
forty years ago, when the majority of Canadians still believed it was
safe to drink and drive," says Dr. Fischer.
"Cannabis is not a benign drug," Dr. Fischer continues. "The evidence
linking patterns of use and problems is strong. We can use this
evidence to provide straightforward, factual information to cannabis
users and their families, friends, or peers, on how to reduce the risks
for problems, and to create screening tools for health professionals to
help address the risks."
Some of the harmful practices and patterns of use documented in the
Cannabis use at a young age - Longitudinal studies suggest that using cannabis from a young age can
be associated with a number of problems, including mental illness and
dependence. While most cannabis users will not progress to other
illicit substance use, those who use cannabis from a young age are far
more likely to make this transition.
Frequent use - Using cannabis often, usually defined as daily or near-daily use, has
been linked to a variety of health problems including cognitive and
memory performance, or risk for dependence.
Cannabis use before driving - Recent data suggests that approximately five per cent of Canadian
adult drivers report driving after cannabis use in the past year, and
high school student surveys show that more students drive after
cannabis use than after drinking alcohol. It is recommended that anyone
using cannabis should not drive for three to four hours after
Cannabis use during pregnancy - While the possible consequences of cannabis use during pregnancy have
not been reliably distinguished from the potentially confounding impact
of alcohol and tobacco use, there is sufficient scientific basis to
recommend abstinence from cannabis use during pregnancy.
"A key message is that the most reliable way to avoid cannabis-related
harms is to abstain from use," says Dr. Fischer. "Those who do use
cannabis need to be advised about patterns of use to avoid problems in
the short and long run. Our guidelines are meant to target the most
dangerous patterns of use among those citizens who use cannabis, and
therefore reduce the possible health problem consequences of such use."
Using scientific evidence to provide guidelines on practices or patterns
of use that substantially reduce the risks of acute and long-term harms
is analogous to the "Low Risk Drinking Guidelines" for alcohol, which
were first introduced in the 1990s. "Given the prevalence and age
distribution of cannabis use in Canada, a public health approach to
cannabis use—including prevention strategies for young people, risk
reduction, and access to treatment—is overdue," according to Dr.
The Canadian Public Health Association endorses the Lower Risk Cannabis
Use Guidelines. "The next step is for health and education authorities
and the wider community to begin discussion of the evidence-based
guidelines, and how this information could best be conveyed to key
target groups in the context of a broad-based public health approach,"
Dr. Fischer says.
*"CIHR/PHAC" refers to the Canadian Institutes of Health Research/Public
Health Agency of Canada
The Centre for Addiction and Mental Health (CAMH) is Canada's largest
mental health and addiction teaching hospital, as well as one of the
world's leading research centres in the area of addiction and mental
health. CAMH combines clinical care, research, education, policy
development, prevention and health promotion to transform the lives of
people affected by mental health and addiction issues.
CAMH is fully affiliated with the University of Toronto, and is a Pan
American Health Organization/World Health Organization Collaborating
SOURCE Centre for Addiction and Mental Health
For further information:
Media contact: Sara Goldvine, CAMH Public Affairs, 416-535-8501x4951