A new study finds that problem drinking in the teen years is not just a phase. Researchers said the key finding of the study is "the more drinking-related problems experienced 
by an adolescent at age 18, the greater the likelihood that adolescent would be diagnosed with alcoholism seven years later, at age 25," said Richard J. Rose, Professor Emeritus in psychology and brain science at Indiana University, Bloomington. However, he added, this may not reflect so much a direct causal effect of adolescent drinking as it does that individuals who transgress social norms in adolescence by drinking heavily may be those same individuals who transgress social norms in adulthood by drinking abusively.

The predictive association was found to be stronger in females than males.

The study also included an analysis of twins which resulted in ruling out factors such as parental
 drinking and household atmosphere as the source of the association.

Source: EurekAlert!
http://www.eurekalert.org/pub_releases/2011-02/ace-wpd020811.php