MORGANTOWN, W.Va. – As states across the country explore the relaxation of marijuana laws, the changes have sparked widespread debate about the actions’ impact on public safety. According to a West Virginia University School of Public Health study recently published by the journal Accident Analysis & Prevention, automobile fatalities linked to drug use have risen sharply over the last decade. However, the role of illegal drugs in these crashes has declined.

“Prescription drug use by drivers in fatal traffic crashes has risen considerably,” Toni Rudisill, doctoral student in epidemiology mentored by Motao Zhu, M.D., Ph.D., associate professor in the WVU School of Public Health and WVU Injury Control Research Center (ICRC), said. “This means there has been a shift in patterns of drug involvement among drivers in recent years.”

In their analysis of data spanning the years 1999 through 2010, Dr. Zhu’s team noted a 49 percent jump in fatal traffic crashes where the driver was found to have tested positive for some sort of drug use. Though drug use among drivers has been recognized as a growing public health and traffic safety concern, Zhu said the specific drugs consumed by fatally injured drivers have not been considered as much as they should.

“Use of opioids, particularly oxycodone, hydrocodone and methadone, and depressants, such as benzodiazepines, has become a community health crisis,” Rudisill said. “Now vehicular crashes involving prescription narcotics and depressants have radically increased as well.”

The number of fatally injured drivers with hydrocodone or oxycodone in their blood streams was up more than six fold in 2009-2010, as compared to 1999-2000. Detected use of methadone among drivers quadrupled over the same period.

Driver use of cannabinoids, the psychoactive compounds that produce marijuana’s “high,” has also increased but could not be classified as entirely illegal for the purposes of this study since a number of states are changing their marijuana laws.

“The problem is likely to worsen,” Zhu explained. “Both the public and healthcare providers need to realize that driving under the influence of drugs – including very common prescription medications – may be extremely hazardous.”

Zhu and his team of researchers analyzed data from the Fatality Analysis Reporting System for the years 1999-2000 and 2009-2010.

The research received funding from the National Institutes of Health, U.S. Institute of Child Health and Development (R01HD074594), the Centers for Disease Control and Prevention, U.S. National Center for Injury Prevention and Control (R21CE001820 and R49CE002109.) Rudisill and Zhu’s co-investigators included Marie Abate, Pharm.D., WVU School of Pharmacy; Jeffrey H. Coben, M.D., WVU School of Public Health and WVU ICRC; and Songzhu Zhao, WVU ICRC.

“Trends in drug use among drivers killed in U.S. traffic crashes, 1999-2010,” is available online at   
For more information: Leigh Limerick, Communication Specialist, 304-293-7087
lal: 05-15-14