Large numbers of American adolescents are putting themselves and others at great risk by driving while under the influence of illicit drugs or alcohol, according to a study funded by the National Institute on Drug Abuse (NIDA), part of the National Institutes of Health (NIH). In 2006, 30 percent of high school seniors reported driving after drinking heavily or using drugs, or riding in a car whose driver had been drinking heavily or using drugs, at least once in the prior two weeks. These findings are based on data obtained from the Monitoring the Future study, in which nationally representative samples of high school seniors have been surveyed annually since 1975. The data analysis is published in the November issue of the Journal of Studies on Alcohol and Drugs.

"These findings are another wake-up call that we cannot afford to be complacent about this great public health risk," said Elias A. Zerhouni, NIH director. "This study shows that not only are too many teens putting themselves and others at risk by driving under the influence of drugs, but that there has been little improvement in the past six years."

Although there was some progress between 2001 and 2003, with rates declining from 35 to 31 percent, between 2004 to 2006 rates leveled off at just under 30 percent.

Dr. Patrick O'Malley, the lead author of the study, observes that, "Driving under the influence is not an alcohol-only problem. In 2006, 13 percent of seniors said they drove after using marijuana while ten percent said they drove after having five or more drinks."

"Most teens are aware of the dangers of drinking and driving, yet many ignore it. And many don't seem to recognize the dangers of driving after using illicit drugs, including marijuana." said Dr. Nora Volkow, NIDA director. "Educational efforts need to be targeted to include the dangers of both drinking and drugged driving."

To inform prevention efforts, the researchers also sought to examine what demographic and lifestyle characteristics were associated with these behaviors. For example, males were more likely than females to drive after heavy drinking or marijuana use. And although there was little correlation between impaired driving and socioeconomic status or geographic region, individual lifestyle factors such as high religiosity, good grades, low truancy, or having two parents living at home were all associated with a lower likelihood of engaging in risky driving behaviors. For example, only 20 percent of those students with an A or A- GPA exposed themselves to these situations as opposed to almost 39 percent with a GPA of B- or below.

"Vehicle accidents are the leading cause of death among those aged 15 to 20," added Dr. Volkow. "Combining the lack of driving experience among teens with the use of marijuana and/or other substances that impair cognitive and motor abilities can be a deadly combination."

The National Institute on Drug Abuse is a component of the National Institutes of Health, U.S. Department of Health and Human Services. NIDA supports most of the world's research on the health aspects of drug abuse and addiction. The Institute carries out a large variety of programs to inform policy and improve practice. Fact sheets on the health effects of drugs of abuse and information on NIDA research and other activities can be found on the NIDA home page at www.drugabuse.gov.

The National Institutes of Health (NIH) — The Nation's Medical Research Agency — includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical and translational medical research, and it investigates the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.