Epidemiology and consequences of drinking and driving

Alcohol Research & Health, Wntr, 2003 by Ralph Hingson, Michael Winter

Alcohol is a major factor in traffic crashes, and crashes involving alcohol are more likely to result in injuries and deaths than crashes where alcohol is not a factor. Increasing blood alcohol concentrations (BACs) have been linked to increased crash risk. Male drivers, particularly those ages 22 to 45; people with drinking problems and prior drinking and driving convictions; and drivers who do not wear safety belts are disproportionately likely to be involved in alcohol-related fatal crashes. Alcohol-dependent people are over-represented in all alcohol-related traffic crashes, as are those who begin drinking at younger ages. Though there are more than 82 million drinking--driving trips in a given year at BACs of 0.08 percent and higher (and 10 percent of drinking--driving trips are at BACs of 0.08 percent and higher), there are only 1.5 million arrests for drinking and driving each year. Despite overall marked reductions in alcohol-related traffic deaths since the early 1980s, there has been little reduction since the mid-1990s, and alcohol-related traffic deaths have increased slightly in the past 3 years. KEY WORDS: drinking and driving; epidemiological indicators; AODR (alcohol and other drug related) accident mortality; traffic accident; impaired driver; risk factors; BAC; seat belt; driver performance; license control, age of AODU (alcohol and other drug use) onset; law enforcement; trend; deterrence of AODU; gender differences; racial differences; age differences

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Despite reductions in alcohol-related traffic fatalities since the early 1980s, alcohol remained a factor in 41 percent of the traffic deaths recorded in the United States in 2002. This article examines the epidemiology of alcohol-related crashes, injuries, and deaths; characteristics of alcohol-related fatalities, fatal crashes, and drivers in alcohol-related fatal crashes; alcohol dependence and alcohol-related crashes; survey data on self-reported drinking and driving; and trends in drinking and driving.

TRAFFIC CRASH DEATHS AND INJURIES

Traffic crashes are the leading cause of death in the United States for people ages 2 to 33 (National Highway Traffic Safety Administration [NHTSA] 2003b). According to NHTSA, 41 percent of people fatally injured in traffic crashes were in alcohol-related crashes (i.e., those in which a driver or pedestrian had a blood alcohol concentration [BAC] greater than zero), and 35 percent were in crashes involving someone with a BAC of 0.08 percent or higher. Of the total number of people injured in traffic crashes, 9 percent were injured in alcohol-related crashes (225,000 out of 2,926,000). (For more information on BAC and fatal crashes, see the sidebar on p. 66.)

Traffic crashes are more likely to result in death or injury if alcohol is involved. Of all alcohol-related crashes in 2002, 4 percent resulted in a death, and 42 percent in an injury. In contrast, of the crashes that did not involve alcohol, 0.6 percent resulted in a death, and 31 percent in an injury.

Many people other than drinking drivers are killed in crashes involving drinking drivers. Overall in 2002, 44 percent of those who died in traffic crashes involving a drinking driver with a BAC of 0.01 percent or higher were people other than the drinking driver: 7 percent were other drivers in vehicles struck by drinking drivers, 22 percent were passengers in vehicles with drinking drivers or struck by drinking drivers, 13 percent were pedestrians, and 2 percent were bicyclists. In 2002, 573 children younger than age 16 died in crashes involving drinking drivers.

CHARACTERISTICS OF ALCOHOL-RELATED FATALITIES AND FATAL CRASHES

Data from the Fatality Analysis Reporting System (FARS) (NHTSA 2003a) reveal that alcohol involvement in fatal crashes varies considerably by gender, age, race/ethnicity, type of vehicle driven, time of day, day of the week, and whether the person involved was a driver, motor vehicle passenger, or pedestrian.

Characteristics of Alcohol-Related Fatalities

Gender: Males are more likely than females to be involved in alcohol-related fatal crashes. In 2002, 78 percent of people killed in alcohol-related crashes (including drivers, passengers, and pedestrians) were male. Forty-six percent of male traffic deaths are alcohol related, compared with 29 percent of female traffic deaths.

Age. Traffic deaths among elderly people and children are less likely to be alcohol related than those among young and middle-aged adults. As shown in table 1, only 15 percent of traffic deaths among adults age 65 and over were alcohol related, compared with 23 percent of traffic deaths among children under age 16, 37 percent among 16- to 20-year-olds, 57 percent among 21- to 29-year-olds, 53 percent among 30- to 45-year-olds, and 38 percent among 46- to 64-year-olds. Alcohol-related traffic deaths are more likely to occur at lower BACs among 16- to 20-year-olds, compared with other age groups. A majority of alcohol-related traffic deaths among 16- to 20-year-olds occur at below 0.15 percent BAC (i.e., referring to the highest BAC of a driver or pedestrian involved in the crash). Overall, however, a majority of traffic deaths occur at above 0.15 percent BAC (NHTSA 2003a).