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Drunks are prone to injury, be it from a rooftop fall, a barroom fight or an oversight while juggling. But new research suggests that once an injury has occurred, the same substance that leads drinkers to folly may help save them from its consequences.

The results of a study from the University of Illinois at Chicago (UIC) show that not only does an appreciable blood-alcohol level seem to increase a trauma victim's chances of survival after being admitted to a hospital, but that the drunker a victim is, the more likely he or she is to survive.

"After an injury, if you are intoxicated there seems to be a pretty substantial protective effect," said Lee Friedman, the author of the study and an assistant professor of environmental and occupational health sciences at UIC, in a statment issued by the school. "The more alcohol you have in your system, the more the protective effect."

Friedman's study shows a correlation between a high blood-alcohol content and an increased chance of survival after a serious injury, but it doesn't necessarily demonstrate that alcohol is the root cause of the increase.

While previous studies have examined the interactions between trauma outcome and blood-alcohol content, most have focused either on particular injuries, such as head trauma, or particular injury mechanisms, such as car accidents.

Friedman analyzed all 190,612 patients treated at Illinois' trauma centers between 1995 and 2009 who were tested for blood-alcohol content, with levels ranging from zero to 0.5 percent at time of admission. (Blood-alcohol levels above about 0.35 percent can be fatal.) He found that with the exception of burn injuries, the mortality rates of all types of traumatic injury decreased as the blood-alcohol content of victims rose. [7 Ways Alcohol Affects Your Health]

At the upper bounds of intoxication, mortality rates were cut by nearly 50 percent, said Friedman. The effect, however, was not equally strong for all types of trauma, with victims of penetrating injuries, such as gunshot and stab wounds, seeming to show the greatest benefit from alcohol.

Friedman broke his data into subgroups, classified by severity and type of injury, before drawing any conclusions, to account for the possibility that drinkers suffer a disproportionate amount of relatively minor traumatic injuries.

There is a folk belief that drunken injuries, especially those incurred during car crashes, are likely to be less severe, due perhaps to increased relaxation or limpness at the time of an accident. But Friedman says his research has convinced him that this belief is "probably grossly overestimated and false."

His findings don't show that a drunk driver's injuries during a car crash are likely to be less serious than those suffered by potential sober victims, just that if all parties suffer the same injuries, the sober ones are more likely to die.

"You don't die from the injury itself, you die from the subsequent physiological response, things like inflammation and rapid fluid loss," Friedman told Life's Little Mysteries. "If you get shot by a gun, it's not the hole that kills you."

And it's when a person's body goes into emergency preservation mode — tripping a cascade of physiological panic buttons that can ironically end in death — that alcohol seems to help most.

Friedman is conducting a follow-up study that looks at the relation between blood-alcohol content and the likelihood of complications that often result from traumatic injury, such as heart and kidney failure. His preliminary data suggests alcohol combats both of those outcomes, and this, he says, is consistent with the boost alcohol gives to myocardial contractility, or the heart's ability to pump blood.

Friedman's study notes that if drunken trauma victims are more likely to die before being hospitalized than their sober counterparts, his data sample may be biased.

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