Researchers have shown that familial risk of developing alcohol related disorders is determined by social consequences of alcohol abuse rather than people's physical dependence on alcohol.

Alcohol Use Disorder (AUD) affects 18 million people in the U.S. AUD is classified under alcohol abuse and alcohol dependence.

Alcohol Abuse (AA) is when a person is not physically dependent on alcohol but has a high risk of developing psychosocial problems due to excessive alcohol intake while Alcohol Dependence (AD) is when the person is physically dependent on alcohol. People with AD may have severe symptoms like withdrawal and craving.

Researchers from the Virginia Commonwealth University School of Medicine studied the effects of AA and AD on familial risk. According to the National Institute of Alcohol Abuse and Alcoholism, a person who has had an alcoholic in the family is at four times the risk of being an alcoholic throughout his/her life.

"We decided to look at the clinical features of AA and AD as they correspond to familial liability to AUDs because familial risk of illness has been long used as a major validator of diagnostic approaches in psychiatry," explained Kenneth S. Kendler, professor of psychiatry at the Virginia Commonwealth University School of Medicine and corresponding author for the study.

Kendler added that in the Diagnostic and Statistical Manual of Mental Disorders-III (DSM-III) criteria, AA and AD were thought to be different syndromes with distinct symptoms. Many studies have shown that these two categories are similar to each other.

The study was based on 1,120 twins from the Virginia Twin Study of Psychiatric and Substance Use Disorders. The participants met the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) criteria for lifetime AUDs. Researchers assessed whether AA or AD predicted familial risk of alcohol abuse.

Researchers found that the negative social consequences of drinking a lot of alcohol reflects a genetic risk of alcohol disorders better than a person's ability to hold on to more liquor.

"Symptoms of alcohol abuse do a better job of reflecting the familial risk for AUDs than symptoms of dependence. This is not what we expected. Clearly the symptoms of alcohol abuse may have more validity than they are commonly given credit for," said Kendler.

Researchers found that a factor significantly determining familial risk was AUD-associated legal problems. The latest diagnostic manual DSM-5 will probably not have this criterion for alcohol use disorders.

"This removal is slated to occur largely through the influence of the International Classification of Diseases 11th Revision (ICD-11) which is used worldwide and is itself slated for revision by 2015. The DSM-5 authors are concerned that legal standards differ so widely across the world that it would be problematic to use any criteria reflecting legal practices," explained Kendler.

New York Times had reported in May that the proposed revision for substance use would put 20 million more people in the category of "addicts."