Teens who are exposed to alcohol are more vulnerable to become "heavy drinkers" in future, revealed a new study on rodents.
The study also cited that while no one can become alcohol dependent (AD) without repeatedly drinking alcohol, but not everyone who does so will become AD.
The findings suggested that some characteristics - adolescence, novelty seeking, reaction to stress, and response to first alcohol exposure - may influence the likeliness to develop AD.
"We know that adolescence is a vulnerable time. People who start drinking the earliest tend to be the most likely to develop drinking problems. But we also know that not all adolescents get into trouble with alcohol and other drugs," explained Nicole L. Schramm-Sapyta, research associate in the department of pharmacology and cancer biology at Duke University Medical Center.
For the study, the researchers examined 48 male Sprague-Dawley rats that were 28 days old - the equivalent of rodent adolescence. Then they measured how much each rat drank in special lickometer cages. The rats were habituated to the cages with water, which was then switched to an alcohol solution for three nights, followed by a choice between the water or alcohol solutions for 10 consecutive nights. After two nights of abstinence, the rats were once again given a day's choice between the water or alcohol solutions in order to measure relapse-like behaviour.
"Our key finding is that drinking patterns may be established after only a few exposures to alcohol. Rats that demonstrated a 'taste' for alcohol after only three nights of drinking were very likely to be the biggest drinkers after longer-term exposure to alcohol," said Schramm-Sapyta.
"The adolescent drinking in this study likely relates to those rats with low sensitivity to the sedative effects of alcohol, coupled with high consumption for adolescents in general. These findings support the interaction of genetics and environmental exposure to alcohol during adolescence as determining life-long drinking. They also support the hypothesis that adolescent drinking may predict risk of alcohol problems," commented Fulton T. Crews, Director of the Center for Alcohol Studies at the University of North Carolina.
Schramm-Sapyta said that one more key finding of the study was that the measures of novelty seeking and stress responsiveness were not related to drinking outcomes.
"This suggests that there are other characteristics that we as scientists should be looking for, which are related to the early experiences of drinking," she said.
She then linked these to humans, and said that people who drink to excess when they first begin might be at higher risk for developing alcoholism.
"The findings suggest that early 'big drinkers' are the people who should be targeted for alcoholism-prevention efforts," she said.
Both Schramm-Sapyta and Crews said these findings have important implications for parents, as well as parental monitoring.
The results are published in the latest issue of Alcoholism: Clinical and Experimental Research.