After a long decline in alcohol-impaired driving, Americans are back at it in a big way.
From 1993 to 1997 the estimated annual number of alcohol-impaired driving instances declined more than one percent per year. A new study finds the rate increased 37 percent from 1997 to 1999, however, and continued to increase in 2002, the most recent year for which data was available.
Four out of five cases were related to what experts call binge drinking, when the driver has had five or more drinks.
The study was done by the Centers for Disease Control and Prevention (CDC) and is published in the May issue of the American Journal of Preventive Medicine.
"This is not just a statistical bump or noise in the data," said University of Chicago researcher Kyran Quinlan. "This is a true behavioral change."
If the behavior can't be curbed, the costs are likely to be high for U.S. residents:
- Motor vehicle accidents are the leading cause of death for people aged 1 to 34.
- Odds already said 30 percent of Americans would be in an alcohol-related crash in their lifetimes.
- Alcohol-related crashes cause an estimated $50 billion in damages every year.
"This tells us that we urgently need new strategies to prevent alcohol-impaired driving with special emphasis on reducing binge drinking," Quinlan said.
The study was based on telephone surveys of more than 100,000 U.S. residents, aged 18 or older, in 1993, 1995, 1997, 1999 and 2002. Those who drank were asked, "During the past month, how many times have you driven when you've perhaps had too much to drink?"
Binge drinkers were 13 times more likely to say they had driven while drunk.
The researchers say the survey likely underestimates the problem, since many respondents -- even though they were promised confidentiality -- were probably reluctant to admit they had driven while under the influence. And the survey didn't even include drivers under age 18.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.