Researchers Identify Alcoholism Subtypes

Jul 6, 2007
Analyses of a national sample of individuals with alcohol
dependence (alcoholism) reveal five distinct subtypes of
the disease, according to a new study by scientists at the
National Institute on Alcohol Abuse and Alcoholism (NIAAA),
part of the National Institutes of Health (NIH).

"Our findings should help dispel the popular notion of the
‘typical alcoholic,’” notes first author Howard B. Moss,
M.D., NIAAA Associate Director for Clinical and
Translational Research. “We find that young adults comprise
the largest group of alcoholics in this country, and nearly
20 percent of alcoholics are highly functional and
well-educated with good incomes. More than half of the
alcoholics in the United States have no multigenerational
family history of the disease, suggesting that their form
of alcoholism was unlikely to have genetic causes.”

“Clinicians have long recognized diverse manifestations of
alcoholism,” adds NIAAA Director Ting-Kai Li, M.D, “and
researchers have tried to understand why some alcoholics
improve with specific medications and psychotherapies while
others do not. The classification system described in this
study will have broad application in both clinical and
research settings.” A report of the study is now available
online in the journal Drug and Alcohol Dependence.

Previous efforts to identify alcoholism subtypes focused
primarily on individuals who were hospitalized or otherwise
receiving treatment for their alcoholism. However, recent
reports from NIAAA’s National Epidemiologic Survey on
Alcohol and Related Conditions (NESARC), a nationally
representative epidemiological study of alcohol, drug, and
mental disorders in the United States, suggest that only
about one-fourth of individuals with alcoholism have ever
received treatment. Thus, a substantial proportion of
people with alcoholism were not represented in the samples
previously used to define subtypes of this disease.

In the current study, Dr. Moss and colleagues applied
advanced statistical methods to data from the NESARC. Their
analyses focused on the 1,484 NESARC survey respondents who
met diagnostic criteria for alcohol dependence, and
included individuals in treatment as well as those not
seeking treatment. The researchers identified unique
subtypes of alcoholism based on respondents’ family history
of alcoholism, age of onset of regular drinking and alcohol
problems, symptom patterns of alcohol dependence and abuse,
and the presence of additional substance abuse and mental
disorders:

Young Adult subtype: 31.5 percent of U.S. alcoholics. Young
adult drinkers, with relatively low rates of co-occurring
substance abuse and other mental disorders, a low rate of
family alcoholism, and who rarely seek any kind of help for
their drinking.

Young Antisocial subtype: 21 percent of U.S. alcoholics.
Tend to be in their mid-twenties, had early onset of
regular drinking, and alcohol problems. More than half come
from families with alcoholism, and about half have a
psychiatric diagnosis of Antisocial Personality Disorder.
Many have major depression, bipolar disorder, and anxiety
problems. More than 75 percent smoked cigarettes and
marijuana, and many also had cocaine and opiate addictions.
More than one-third of these alcoholics seek help for their
drinking.

Functional subtype: 19.5 percent of U.S. alcoholics.
Typically middle-aged, well-educated, with stable jobs and
families. About one-third have a multigenerational family
history of alcoholism, about one-quarter had major
depressive illness sometime in their lives, and nearly 50
percent were smokers.

Intermediate Familial subtype: 19 percent of U.S.
alcoholics. Middle-aged, with about 50 percent from
families with multigenerational alcoholism. Almost half
have had clinical depression, and 20 percent have had
bipolar disorder. Most of these individuals smoked
cigarettes, and nearly one in five had problems with
cocaine and marijuana use. Only 25 percent ever sought
treatment for their problem drinking.

Chronic Severe subtype: 9 percent of U.S. alcoholics.
Comprised mostly of middle-aged individuals who had early
onset of drinking and alcohol problems, with high rates of
Antisocial Personality Disorder and criminality. Almost 80
percent come from families with multigenerational
alcoholism. They have the highest rates of other
psychiatric disorders including depression, bipolar
disorder, and anxiety disorders as well as high rates of
smoking, and marijuana, cocaine, and opiate dependence.
Two-thirds of these alcoholics seek help for their drinking
problems, making them the most prevalent type of alcoholic
in treatment.

The authors also report that co-occurring psychiatric and
other substance abuse problems are associated with severity
of alcoholism and entering into treatment. Attending
Alcoholics Anonymous and other 12-step programs is the most
common form of help-seeking for drinking problems, but
help-seeking remains relatively rare.

Other co-authors of the study include Chiung M. Chen, M.A.
and Hsiao-Ye Yi, Ph.D., of the Alcohol Epidemiologic Data
System at CSR Inc., in Arlington, Virginia.

http://www.nih.gov/news/pr/jun2007/niaaa-28.htm