New Study Sheds Light on Drugged Driving Trends

The number of drivers mixing drugs before getting behind the wheel has been on the upswing since 1993, according to a new study.

Drugged drivers accounted for over 11 percent of drivers involved in fatal car accidents in 2010.

In 1993, 32.6 percent of drug users tested positive for multiple drugs; by 2010, 45.8 percent of drugged drivers tested positive for multiple substances. Approximately half of drugged drivers involved in fatal crashes had also consumed alcohol, and nearly 75 percent of drivers with cocaine in their system tested positive for alcohol use.

Only about 1 in 8 drivers in 1993 were under the influence of three or more drugs, but by 2010 the proportion of drivers mixing three or more drugs was up to 1 in 5.

The study also showed that prescription drug use has been on the rise, with more than 46 percent of drugged drivers under the influence of prescription drugs. Prescription drug use now represents the largest share of drugged drivers, with most of the upswing occurring since the mid-2000’s.

The new research also shows a correlation between age and drug preference. Nearly 60 percent of drivers under the influence of marijuana only were younger than 30, and nearly 40 percent of prescription drug users were at least 50 years old.

Overall, the study demonstrates the changing profile of the American drug user. Drugged drivers are more likely now than 20 years ago to be under the influence of marijuana, prescription drugs, or multiple drugs.

“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,” said study author Fernando Wilson in a news release. “However, it is unclear whether current state policies are completely up to the challenge of addressing the growing issue of drugged driving.”

The findings also show demographic patterns in drugged driving. Roughly three-quarters of drivers under the influence of drugs were male, and more than 40 percent of the drug-related fatal crashes occurred in the South.

Less than half of U.S. states have enacted some kind of zero-tolerance law for drugged driving, and the University of Nebraska researchers behind this study have doubts about the efficacy of such laws. According to the National Highway Traffic Safety Administration data used in the study, states with zero-tolerance laws have not seen a significant reduction in drugged-driving fatalities.

The study, published in Public Health Reports, looked at data from the National Highway Traffic Safety Administration to examine fatal car accidents that occurred between 1993 and 2010. Funding for the study was provided by Public Health Law Research.

According to the 2012 National Survey on Drug Use and Health, an estimated 10.3 million people over the age of 12 reported driving under the influence of drugs during the prior year. The NHTSA National Roadside Survey found that over 16 percent of nighttime drivers on the weekends tested positive for illegal, prescription, or over-the-counter drugs in 2007.