The clinically meaningful link between alcohol use and attention deficit hyperactivity disorder

Alcohol Research & Health, Spring, 2002 by Bradley H. Smith, Brooke S.G. Molina, William E. Pelham, Jr.

Attention deficit hyperactivity disorder (ADHD) is a childhood mental health disorder that can lead to alcohol and other drug (AOD)-related problems if it persists into adolescence and adulthood. Several findings suggest that ADHD contributes to the development of AOD use disorders. ADHD generally precedes alcohol use and is correlated with developmentally inappropriate levels of alcohol use or abuse; conduct problems typically precede the development of alcohol use or abuse. The potential role of ADHD in the development of AOD use problems has important implications for prevention and treatment of such problems. For example, people with ADHD have poor outcomes from AOD abuse treatment. Service providers who work in AGO abuse treatment settings must develop the diagnostic and clinical expertise to address co-occurring ADHD and AOD use disorders. KEY WORDS: attention deficit disorder with hyperactivity; alcohol and other drug dependence; alcoholic beverage; comorbidity; impulsive behavior; symptom; early AODU (alcohol and other drug use) onset, conduct disorder; diagnostic criteria; causal pathways; predictive factor; treatment outcome; correlation analysis; literature review

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Attention deficit hyperactivity disorder (ADHD) is a childhood mental health disorder that is characterized by inattention, impulsivity, and hyperactivity. It has been discussed in the psychiatric literature for approximately 100 years under various names, including minimal brain dysfunction; hyperkinetic reaction of childhood; attention deficit disorder; and, since 1987, ADHD. The various names reflect an evolving understanding of the disorder and an increasing consensus on its nature. One of the major recent advances in the research on ADHD is the recognition that most people who are diagnosed with it as children continue to suffer problems related to this disorder as adolescents and adults (Barkley 1998; Tucker 1999). This recognition that ADHD extends beyond puberty has expanded ADHD research into new areas, including the link between ADHD and alcohol use and abuse.

To provide the appropriate background for understanding the link between ADHD and alcohol use, this article first summarizes the diagnostic criteria for ADHD. It then examines the hypothesis that ADHD is a causal factor in the development of problematic alcohol consumption. Finally, the article reviews some preliminary research suggesting that ADHD and its treatment may have important implications for the prevention and treatment of alcohol-related problems.

DIAGNOSIS OF ADHD

According to the American Psychiatric Association (APA) (2000), the rate of ADHD in the general population of children in the United States is between 3 and 7 percent. Among children receiving treatment for psychiatric disorders in clinical settings, however, this rate often exceeds 50 percent (Barkley 1998), making ADHD one of the most commonly diagnosed psychiatric disorders for children in the United States. The rare of ADHD in adults is thought to be somewhat lower than in children, probably between 2 and 5 percent in the general population (Barkley 1998). For adults in clinical settings, the rate of ADHD is currently unknown bur appears to be substantially elevated compared with the general population. Among adult patients receiving treatment for alcohol and other drug (AOD) abuse, the rate of ADHD has been estimated to be approximately 25 percent (Wilens 1998). A similar rare of ADHD, about 30 percent, has been found among adolescents in treatment for AOD use disorders (AODD) (Molina et al. 2002). These relatively high rates indicate that it is important for service providers in AOD-abuse treatment settings to be able to diagnose and treat ADHD.

The symptoms or problems associated with ADHD vary somewhat depending on the patient's developmental stage (Barkley 1998). Children with ADHD typically present with academic difficulties, discipline problems at school and at home, and conflicts with peers. Adolescents with ADHD exhibit many of the same problems but often with more serious consequences, such as dropping out of school or experiencing legal problems. Moreover, because of their physical and social maturation, adolescents with ADHD encounter new sets of problems, such as sexual activity and pregnancy and AODD. In adults with ADHD, school-related problems may no longer be relevant, but social problems often persist and new challenges may develop related to driving (e.g., traffic violations), vocational achievement, and sustaining friendships and romantic relationships.

The most recent set of criteria for a diagnosis of ADHD as listed in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (APA 2000) (see textbox) reflects the theory that ADHD is made up of two major dimensions: inattention and hyperactivity/impulsivity. Overall, the symptoms associated with ADHD fall into three categories--inattention symptoms, hyperactivity symptoms, and impulsivity symptoms. Factor analytic studies (1) have found that inattention symptoms represent a single dimension that is reasonably distinct from hyperactivity and impulsivity (e.g., Lahey et al. 1988; Molina et al. 2001). 1-lyperactivity symptoms and impulsivity symptoms, however, are not distinct from each other and combine to form a dimension that is separate from inattention (Barkley 1998; Milich et al. 2002). Because symptoms from both dimensions can co-occur, however, three major subtypes of ADHD exist: