"I don't remember how I got home from the party." This could be a text from last night to one hard-partying college student from another.
New research from Northwestern Medicine shows that 50 percent of college drinkers report at least one alcohol-induced memory blackout -- a period of amnesia -- in the past year during a drinking binge. Despite being fully conscious during such blackouts, students could not recall specific events, such as how they got to a bar, party or their own front door.
Published in Injury Prevention, May 2011, the study found college drinkers who reported alcohol-induced memory loss are at a higher risk of alcohol-related injuries in the next 24 months versus their peers drank just as much but didn't report memory blackouts. It also offers a new tool for doctors to screen college drinkers for blackouts by asking them a few simple questions.
"The study offers a major warning to student drinkers: if you blackout, you need to cut back on your drinking because the next time it happens you could be driving a car or walking on a bridge and something bad could happen," said Michael Fleming, M.D., co-author of the study.
Fleming is interim chair and professor in family and community medicine and professor of psychiatry and behavioral sciences at Northwestern University Feinberg School of Medicine.
"If doctors screen college drinkers for these kinds of blackouts, they could do a better job of identifying and intervening with college students at the highest risk of alcohol-related injuries," Fleming said.
During the screening, students were asked, "Have you ever suddenly found yourself in a place that you could not remember getting to?" and "How many times has this happened to you because you were drinking or because of your drinking in the past year?"
When you are in a blackout you are fully conscious, but you don't really know what you are doing, and the choices you make can be irrational, risky and dangerous, Fleming said.
"This study shows that these blackouts are strong predictors of future alcohol-related injuries," he said.
Fleming, along with researchers at the University of Wisconsin-Madison, analyzed data collected from full-time college students at four U.S. universities and one Canadian university who were flagged as heavy drinkers through a screening and physician intervention project. Male students in the study reported drinking at least 50 alcoholic drinks and female students at least 40 alcoholic drinks in the past 28 days. The men drank more than five drinks and the women drank more than four during heavy-drinking episodes.
Nearly 50 percent of the students studied reported alcohol-induced memory blackouts at least once during the past year and five percent had experienced alcohol-related amnesia in the past seven days. The results also showed the more blackouts a student had in the past year, the higher his or her risk of alcohol-related injuries in the future.
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