Since the early ’90s, the characteristics of drivers who are taking drugs and are involved in car crashes have drastically changed. A new study indicates that more drivers are testing positive for prescription drugs, cannabis, and multiple drugs, and they are more likely to be older than 50.
“While we’ve seen a decrease over the years in motor vehicle fatalities involving people under the influence, the nature of those crashes is changing,” says study author Fernando Wilson, PhD., associate professor at the University of Nebraska Medical Center in Omaha.
The researchers looked at trends in the characteristics of US drivers who were involved in fatal crashes between 1993 and 2010 who tested positive for drugs. The study was done to investigate the relationship between state laws and the consumption of alcohol and other drugs on fatal car crashes.
The results were that the percentage of drugged drivers with three or more drugs in their system nearly doubled from 1993 to 2010, increasing from 11.5 percent to 21.5 percent. Drugged drivers who were tested for drug use accounted for 11.4 percent of all drivers involved in fatal motor vehicle crashes in 2010.
These are other results from the study:
• Drugged drivers were increasingly likely to be older drivers, and the percentage using multiple drugs increased from 32.6 percent in 1993 to 45.8 percent in 2010.
• About half (52.4 percent) of all drugged drivers used alcohol, but nearly three-quarters of drivers testing positive for cocaine also used alcohol.
• Prescription drugs accounted for the highest fraction of drugs used by drugged drivers in fatal crashes in 2010 (46.5 percent), with much of the increase in prevalence occurring since the mid-2000s.
“In 1993, about one in eight drivers were using multiple drugs concurrently,” says Wilson. “By 2010, it was closer to one in five. That’s a large increase in drug use.”
He adds that there are more people using drugs and alcohol together and driving.
“About 70 percent of drivers who tested positive for cocaine had also been consuming alcohol, and almost 55 percent of drivers who tested positive for cannabis also had alcohol in their systems,” Wilson explains .
The researchers also found trends in drug use associated with age: Almost 60 percent of marijuana-only users were younger than 30 years old, but 39 percent of prescription users were 50 years old or older. This trend seems to reflect an overall increase in the use of prescription drugs by Americans in general, with 90 percent of people ages 65 and older taking some kind of prescription medication.
“These trends are likely to continue into the future given the aging U.S. population, an increasing reliance on prescription medications by medical providers, and increasing initiatives to legalize marijuana” says Wilson. “However, it is unclear whether current state policies are completely up to the challenge of addressing the growing issue of drugged driving.”
Eighteen states currently have “per se,” or zero tolerance, laws for drugged drivers. Recent studies have shown, however, that these laws may not have been effective in decreasing traffic deaths.
The researchers suggest that policy makers consider measures that would increase primary prevention of drug use by drivers, such as limiting prescription drug use by drivers through counseling by medical professionals, and increasing affordable access to mass transit.
In 2010, 42 states had prescription monitoring programs that included prescription drugs. These programs are meant to curb drug abuse, and specifically prevent overdose.