Alcohol Important in Injury Mortality

The first comprehensive study of alcohol's role in fatal injuries has shown that alcohol is often an important factor. Based on an analysis of published medical examiners' reports from across the country, researchers at the Johns Hopkins School of Public Health found that alcohol consumed to the level of intoxication contributed to approximately 32% of homicides, 31% of accidental injuries, and 23% of suicides. The percentage for alcohol intoxication in fatal car crashes is 33%. The study appeared in the June 1999 issue of the Annals of Emergency Medicine.

Lead author Gordon Smith, MD, MPH, associate professor, Health Policy & Management, said, "In the past, estimates of alcohol's role in these types of injuries varied widely because of the lack of comprehensive data and the limited quality of regional data. Most studies of non-vehicular injuries were limited because of the small number of cases studied." In contrast, detailed national data is available annually on alcohol involvement in motor vehicle fatalities.

Dr. Smith's group reviewed a total of 65 studies by U.S. medical examiners published between 1975 and 1995. Data were separated by cause of death and narrowed down to three categories: death attributed to unintentional injury (7,459); homicide (28,696); and suicide (19,347). The researchers analyzed the blood alcohol concentrations (BAC) of each group of victims. Those with a BAC of 100 milligrams per decaliter of blood (equivalent to .10 mg), or higher were considered intoxicated at the time of death, a level consistent with the cut-off values commonly used to determine whether someone has been driving while intoxicated.

Homicide victims had the highest percentage of intoxication at the time of death (31.5%), followed by unintentional injury deaths (31%) and suicides (22.7%). There was also considerable variation within each category according to the way in which the person died. For instance, in the suicide group, the highest intoxication rate was found in those who poisoned or shot themselves (35% and 31%) compared to only 4% who jumped to their deaths. Among unintentional deaths, those caused by burns and by hypothermia had the highest intoxication rate (41% to 42%) and firearm deaths had the lowest (21%).

Dr. Smith acknowledged that one limitation of a study of this kind is the paucity of data available on those who committed the homicides, as only the victims are tested. He also said that an in-depth look at the role gender and age play in the outcome would be helpful as little data is available on how alcohol involvement varies in these groups. For motor vehicles, there was a wide variation by age and gender with the highest proportion intoxicated being males 25-34 years old and the lowest being the elderly over the age of 65.

Support for this study was provided by grants from the National Institute on Alcohol Abuse and Alcoholism (NIAAA).