Marijuana users more than two times more likely to crash
Smoking or ingesting marijuana is becoming more and more common, and an online study from Epidemiologic Reviews shows that drivers who smoke marijuana before getting behind the wheel are at roughly twice the risk of crashing motor vehicles than those who do not smoke marijuana and then drive.
The authors of the study say the findings are particularly relevant in the current climate because of the move to legalize marijuana usage in many states.
"As more and more states consider medical use of marijuana, there could be health implications," said lead author Dr. Guohua Li.
Li, a professor of epidemiology at ColumbiaUniversity Mailman School of Public Health in New York City, said that although alcohol usage has decreased over the last few years, more and more people are smoking pot. One survey conducted in 2009 showed that more than 10 million marijuana users over the age of 12 had used the drug and then gotten behind the wheel, an alarming number to those who know how marijuana use can affect fine motor skills.
Marijuana is more commonly found in drivers after accidents than any other illegal drug. Li and his fellow researchers used date from nine prior studies in six different countries to assess the risk of driving for those who have been smoking marijuana. According to their results, which analyzed data of those who used marijuana as little as an hour before driving to those who used it as far back as a year before driving, driving in the three- to four-hour time range after smoking marijuana is the most dangerous.
The study authors said that marijuana use made driving 2.7 times riskier. Other officials, though, caution against jumping to any conclusions.
"We can't really say yet that marijuana increases the risk by two or three times," said director of statistics at the Insurance Institute for Highway Safety Chuck Farmer. "Most of their studies pointed to a very strong bad effect of marijuana on driving, but there are other studies out there that actually go the other way."
The study did not directly look into medical marijuana use.