Pathological gambling and alcohol use disorder

Alcohol Research & Health, Spring, 2002 by Jon E. Grant, Matt G. Kushner, Suck Won Kim

Problematic gambling is more common among people with alcohol use disorders (AUDs) (i.e., either alcohol abuse or dependence) compared with those without AUDs. This association holds true for people in the general population and is even more pronounced among people receiving treatment. No broadly accepted explanation for the link between problematic gambling and AUD currently exists. The available literature suggests that common factors may increase the risk for both conditions. For example, a defect of functioning in a particular brain system may underlie both conditions. This hypothesis should be further developed using brain imaging and psychopharmacological studies. Effective treatment and prevention will require additional research into relevant associations on both the event level (e.g., the effects of drinking on gambling behavior and vice versa) and the syndrome level (e.g., the relative onset and course of each condition among those who have either one or both disorders). A prudent interpretation of the available data suggests careful screening and treatment when necessary for problematic gambling among people with alcohol abuse and for alcohol abuse among people with gambling problems. KEY WORDS: pathological gambling; AODD (alcohol and other drug dependence); comorbidity; etiology; diagnostic criteria; disinhibition; impulsive behavior; ventral tegmental area; encephalopathy; naltrexone; genetic linkage; causal path analysis; treatment outcome

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Pathological gambling (PG) is characterized by a persistent maladaptive pattern of gambling behavior. PG was first formally included in the Diagnostic and Statistical Manual of Mental Disorders, Third Edition (DSMIII) in 1980 (American Psychiatric Association [APA} 1980). Currently, PG is classified under the category "disorders of impulse control not elsewhere classified" (APA Committee on Nomenclature and Statistics 2000).

This article explores the association between pathological gambling and alcohol use disorders (AUDs) (i.e., the general name for either alcohol abuse or alcohol dependence). It first examines the separate and overlapping prevalences of PG and AUD as estimated by epidemiological surveys conducted in both community and clinical samples. The article then reviews the processes and mechanisms that might account for the frequent co-occurrence of these disorders. Finally, it examines what the co-occurrence of these disorders implies for treatment and highlights promising areas for future research.

Many terms have been used to describe people with problematic gambling behavior (see Cunningham-Williams and Cottler 2001). In this article, PG refers to pathological gambling as diagnosed using DSM diagnostic criteria. The term "disordered gambling behavior" is used to refer to problematic gambling behavior that is not defined by DSM diagnostic criteria. Note, however, that this term is not used as a means of identifying a less serious gambling problem compared with PG. Rather, this term is used to distinguish between problem gambling formally shown to meet the DSM criteria (PG) and all other cases of problematic gambling behavior (disordered gambling behavior).

EPIDEMIOLOGY

Pathological Gambling

During the 1990s, changes in State and local legislation encouraged the expansion of all types of wagering (e.g., casino gambling, lotteries, Internet gambling). As an apparent consequence, gambling and gambling-related problems are on the rise in the United States and Canada. A recent meta-analysis of 120 published studies estimated that 1.6 percent of adults in the United States and Canada meet the DSM criteria for pathological gambling at some point in their lives (Shaffer et al. 1999). Among people younger than 18 years of age, the current prevalence of PG is estimated to be 3.9 percent, with past-year rates for adults and adolescents estimated at 1.1 percent and 5.8 percent, respectively (Shaffer and Hall 1996).

Slightly lower prevalence rates of PG were found by a national study conducted by the National Opinion Research Center (NORC). This study found the lifetime prevalence of adult pathological gambling to be 0.9 percent, with past-year rates of 0.6 percent (NORC 1999).

Although studies using historical review (i.e., retrospective methodologies) have tended to point to a young age of onset of PG (Cunningham-Williams and Cottler 2001), more definitive studies that follow participants over time (i.e., prospective studies) to determine the natural course of PG have yet to be conducted. Studies looking at cross sections of different age groups have shown that PG prevalence rates appear higher for adolescents and young adults than for middle-aged and older adults (Shaffer and Hall 1996). Long-term studies are necessary, however, to clarify these findings.

AUD

Based on DSM-III criteria, the Epidemiologic Catchment Area (ECA) survey estimated that 13.8 percent of adults in the United States meet the criteria for AUD at some time during their lives (Robins et al. 1991). According to findings from the National Comorbidity Survey (NCS) (Kessler et al. 1994), the estimated lifetime prevalence is 14.2 percent for alcohol dependence and 9.4 percent for alcohol abuse, based on criteria in the DSM-III-R (APA 1987). The National Longitudinal Alcohol Epidemiologic Survey (NLAES) found that over the 12 months preceding the survey, 4.4 percent of adults age 18 or older met the criteria for alcohol dependence and 3.0 percent met the criteria for alcohol abuse (Grant et al. 1994). In sum, between 7 percent and 14 percent of adults in the United States experience an AUD at some point in their lives.