TUESDAY, Feb. 22, 2011 (HealthDay News) -- Ignition devices that prevent people from driving after drinking greatly reduce the number of new arrests of drivers who were previously arrested for drunk driving, U.S. researchers report.
The team with the U.S. Centers for Disease Control and Prevention Community Guide branch reviewed 15 studies on ignition interlocks, devices that prevent someone from operating a vehicle if their blood alcohol concentration (BAC) is above a specified level, usually 0.02 to 0.04 grams per deciliter. The minimum illegal BAC is 0.08 g/dL in every state.
Ignition interlocks work by sampling a driver's breath before the vehicle can be started and periodically while the vehicle is being driven. The devices are often mandated for people who have been convicted of drunk driving, the CDC said.
The researchers' review found that the use of ignition interlocks led to a 67 percent decrease in the number of drivers who were re-arrested for drunk driving, compared to those whose licenses were simply suspended.
The findings appear in the March issue of the American Journal of Preventive Medicine.
"When offenders' licenses are suspended, they aren't legally able to provide transportation for themselves and others who may rely on them to get to places like school and work," study author Randy Elder, scientific director of systematic reviews with the Community Guide branch, said in a CDC news release. "Ignition interlocks allow offenders to keep operating their vehicles legally. At the same time, they effectively ensure that they do so more safely -- not under the dangerous effects of alcohol."
Currently, 13 states require ignition interlocks for all people convicted of drunk driving, including first offenders. More than half of states require interlocks for some offenders, such as those with multiple drunk driving convictions or those who had an extremely high blood alcohol level at the time of arrest, the CDC said.
Even so, only a small proportion of convicted drunk drivers participate in interlock programs, said the study authors.
"Each day, more than 30 people die because of alcohol-impaired driving. We know that interlock devices can save lives. More widespread use of ignition interlocks will reduce alcohol-related crash deaths and injuries," CDC Director Dr. Thomas R. Frieden said in the news release.
In 2009, impaired driving-related crashes caused nearly 11,000 deaths in the United States -- nearly one-third of all traffic deaths. The annual cost of impaired driving in the United States is more than $110 billion, the CDC said.
The U.S. National Highway Traffic Safety Administration has more on impaired driving.