Cannabis linked to higher road deaths
13 February 2012, 09:26
Paris - Driving under the influence of cannabis almost doubles the risk
of a serious accident, according to a paper published on Friday in the
British Medical Journal (BMJ).
The risk of collision is substantially higher if the driver is aged under 35, it said.
The study seeks to filter out factors such as alcohol use that can skew inquiries into cannabis and road accidents.
It is an overview of nine previously-published papers which looked at more than 49 000 people.
investigations were deemed to be of high quality because the driver had
given a blood sample after the accident or admitted to smoking cannabis
before to the event.
The nine studies also matched cannabis users against counterparts who did not take the drug to get an idea of the level of risk.
overview by researchers from Dalhousie University in Canada's Nova
Scotia, was unable to investigate a key question - how much of cannabis'
active ingredient, tetrahydrocannabinol (THC), is needed to impair
driving or worsen the risk of a smash.
Cannabis may also be a risk factor for minor collisions, which were not part of the study's scope, the authors added.