The ASAM Principles of Addiction Medicine 5th Edition

39. Pathologic Gambling: Clinical Characteristics and Treatment

Jon E. Grant, MD, JD, MPH, Brian L. Odlaug, MPH, and Liana R.N. Schreiber, BA

CHAPTER OUTLINE

■  EPIDEMIOLOGY

■  TREATMENT

Pathologic gambling is a psychiatric disorder character-ized by persistent and recurrent maladaptive patterns of gambling behavior, which is associated with impaired functioning, reduced quality of life, and high rates of bankruptcy, divorce, and incarceration (1). Excessive gambling behaviors have been reported for millennia across cultures and have been discussed in the medical literature since the early 1800s (2). Pathologic gambling, however, was recognized by the American Psychiatric Association only in 1980 in their third edition of the Diagnostic and Statistical Manual (DSM-III) (3).

Currently classified in DSM-5 as an “non-substance-related disorder,” the diagnosis of gambling disorder requires that a person meet five of the possible 9 criteria listed for the disorder. These criteria include (a) gambles when distressed; (b) the need to gamble with higher amounts of money (tolerance); (c) has tried unsuccessfully to stop or cut back on gambling; (d) feels restless or irritable when not able to gamble; (e) gambles to escape from a mood or problems; (f) chasing losses; (g) lies to family, friends, and others about the amount or extent of gambling; (h) has lost or put into jeopardy a job, educational, or other opportunity due to gambling; and (i) has needed others to pay for finances due to gambling losses. Further, the gambling must not be better accounted for by a manic episode. The term problem gambling has been used to describe forms of disordered gambling, sometimes inclusive and at other times exclusive of pathologic gambling. Problem gambling, like problem drinking, is not an officially recognized disorder by the American Psychiatric Association.

The concept of behavioral addictions has some scientific and clinical heuristic value but remains controversial (see Chapter 5). This is probably so because pathologic gambling is often resistant to treatment, and it remains unclear whether the treatment technologies of traditional addiction treatment (group, 12-step participation, relapse prevention, motivational enhancement, etc.) are superior, inferior, or equivalent or need to be combined with those of psychiatric treatments (medication, cognitive–behavioral therapy [CBT], psychotherapy). Nonetheless, evidence supports significant phenomenologic, clinical, epidemiologic, and biologic links with substance use disorders (4,5). These data support the conceptualization of pathologic gambling as a “behavioral”—as opposed to a chemical—addiction. Issues around behavioral addictions were debated in the context of development of DSM-5 (6). Not only is substance use disorder research likely to be illustrative for pathologic gambling, but the study of pathologic gambling presents an opportunity to study addictive behaviors without necessarily being confounded by neurotoxicity associated with acute or chronic substance use (7). As such, it seems increasingly important that individuals involved in the prevention and treatment of substance use disorders have a current understanding of pathologic gambling and the potential for future research findings to guide prevention and treatment efforts for addictions in general.

EPIDEMIOLOGY

A range of prevalence estimates have been reported for pathologic gambling depending upon the time frame of the study and the instruments used to diagnose the disorder. Only four national studies and one meta-analysis of state and regional surveys have examined prevalence estimates of pathologic gambling in the general US population. The first national study in 1976 noted that 0.8% of 1,749 adults contacted via telephone survey had a significant gambling problem (8). Twenty years later, the National Opinion Research Center at the University of Chicago conducted a national telephone survey (requested by the National Gambling Impact Study Commission) of 2,417 adults and found a lifetime prevalence estimate of 0.8% of pathologic gambling and an additional 1.3% of problem gambling (9). Another national telephone survey of 2,628 adults found that 1.3% had current pathologic gambling measured by the Diagnostic Interview Schedule and 1.9% when measured by the South Oaks Gambling Screen, and an additional 2.8% to 7.5% had problem gambling (10). A recent study, the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), however, found that only 0.42% of adults in a community sample met current criteria for pathologic gambling (11). A meta-analysis of 120 prevalence estimate surveys completed in North America from the late 1970s to the late 1990s found that the lifetime estimate of pathologic gambling was 1.6% and of problem gambling was 3.85%, and for a combined rate of 5.45% for some kind of disordered gambling (12); however, gambling exposure may influence prevalence rates of pathologic gambling (13). A global public health concern, similar rates of pathologic gambling have been reported in other countries (1418).

The incidence of pathologic gambling appears higher in clinical samples. In subjects seeking treatment for substance use disorders, lifetime estimates of pathologic gambling range from 5% to 33% (1921). In studies of psychiatric inpatients, estimates of lifetime pathologic gambling have ranged from 4.9% in adolescents to 6.9% in adults (2225).

There has been an accelerated proliferation of gambling venues during the past decade, particularly with online gaming, Native American casinos, and riverboat gambling (26,27). With increased opportunity to gamble, some research suggests that we can expect greater rates of patho-logic gambling in the future (12,28,29). Physicians, therefore, will likely be seeing more individuals struggling with pathologic gambling and need to be skilled in assessing and treating this disorder.

Clinical Characteristics

Pathologic gambling often begins in adolescence or early adulthood, with males tending to start at earlier ages (12,30,31). Although prospective studies are largely lacking, pathologic gambling appears to follow a trajectory similar to that of substance dependence, with high rates in adolescent and young adult groups, lower rates in older adults, and periods of abstinence and relapse (32). Pathologic gambling can be a serious psychiatric disorder, but there is recent evidence that approximately one-third of individuals with pathologic gambling experience natural recovery (i.e., without formal treatment or attendance at Gamblers Anonymous) (33). The research on natural recovery, however, is based on retrospective reports, and there are no data regarding whether these individuals who are symptom free for 1 year remain free of symptoms beyond that time or whether they relapse or change addictions.

Significant clinical differences have been observed in men and women with pathologic gambling (34,35). Men with pathologic gambling are more likely to be single and living alone as compared to women with the disorder (36). Male pathologic gamblers are also more likely to have sought treatment for substance abuse (37), have higher rates of antisocial personality traits (30), and have marital consequences related to their gambling (30). Though men seem to start gambling at earlier ages and have higher rates of pathologic gambling, women, who constitute approximately 32% of pathologic gamblers in the United States, seem to progress more quickly to severe consequences than do men (3840). But, women with pathologic gambling are more likely to recover from and to seek treatment for their gambling problem (41).

The types of gambling preferred by men tend to be different from those preferred by women. Men with pathologic gambling have higher rates of “strategic” forms of gambling, including sports betting, video poker, and blackjack. Women, on the other hand, have higher rates of “nonstrategic” gambling, such as slot machines or bingo (39,42). In regard to gambling triggers, though both men and women report that advertisements trigger their urges to gamble, men tend to report gambling for reasons unrelated to their emotional state, whereas women report gambling to escape from stress or owing to depressive states (31,37,39,42,43). Higher rates of sensation-seeking or “action”-seeking behavior in men have been suggested as a possible reason for this difference in gambling preference (39,44,45).

Functional Impairment, Quality of Life, and Legal Difficulties

Individuals with pathologic gambling suffer significant impairment in their ability to function socially and occupationally. Many individuals report intrusive thoughts and urges related to gambling that interfere with their ability to concentrate at home and work (43). Work-related problems such as absenteeism, poor performance, and job loss are common (38). The inability to control behavior about which a person has mixed feelings may lead to feelings of shame and guilt (43). Pathologic gambling is also frequently associated with marital problems (43) and diminished intimacy and trust within the family (46). Financial difficulties (44% of pathologic gamblers report loss of savings or retirement funds, and 22% report losing homes or automobiles or pawning valuables owing to gambling) often exacerbate personal and family problems (43).

With the functional impairment that these individuals experience, it is not surprising that they also report poor quality of life. In three studies systematically evaluating quality of life, individuals with pathologic gambling reported significantly poorer life satisfaction compared to general, nonclinical adult samples (4749).

Pathologic gambling is also associated with greater health problems (e.g., cardiac problems, liver disease) and increased use of medical services (5054). Possible reasons for the association of pathologic gambling with health problems might be the sedentary nature of gambling, reduced leisure and exercise time, reduced sleep (55), increased stress, and increased nicotine and alcohol consumption (11).

Many individuals with pathologic gambling report the need for psychiatric hospitalization owing to the depression, and rarer, suicidality, they feel was brought on by their gambling losses (42). Research on individuals in gambling treatment centers has found that 48% of individuals report having had gambling-related suicidal ideation at some time (56). The often overwhelming financial consequences, such as bankruptcy (57), associated with pathologic gambling may also contribute to attempted or completed suicide. A study of Gamblers Anonymous participants (recruited through a gambling telephone hotline) found that 17% to 24% reported having attempted suicide owing to gambling (58).

In addition to the emotional impact of problem and pathologic gambling, many individuals with pathologic gambling have faced legal difficulties related to their gambling. One study found that 27.3% of pathologic gamblers had committed at least one gambling-related illegal act (59). Problem or pathologic gambling may lead people to engage in illegal behavior including embezzlement, stealing, and writing bad checks in order either to finance the gambling behavior or to compensate for past losses related to the excessive gambling (58). Another study found high percentages of pathologic gamblers endorsing prior acts of embezzlement (31%) and robbery (14%) (60).

Although pathologic gambling is associated with multiple legal and functional difficulties, one caveat is that the research is based on relatively small numbers of individuals seeking treatment for pathologic gambling, and therefore, these studies may reflect the more severe cases of pathologic gambling.

Comorbidity

Psychiatric comorbidity is common in individuals with pathologic gambling (61). Frequent co-occurrence has been reported between substance use disorders (including nicotine dependence) and pathologic gambling, with the highest odds ratios generally observed between gambling and alcohol use disorders (10,62,63). A Canadian epidemiologic survey estimated that the relative risk for an alcohol use disorder is increased 3.8-fold when disordered gambling is present (64).

Among clinical samples, 52% of Gamblers Anonymous participants reported either alcohol or drug abuse (65), and 35% to 63% of individuals seeking treatment for pathologic gambling also screened positive for a lifetime substance use disorder (1), rates notably higher than that found in the general population (26.6%) (66). Similarly, a recent study of 84 treatment-seeking pathologic gamblers noted lifetime rates of attention deficit hyperactivity disorder in 26.3% of the sample, much higher than general population rates of 4% to 5% (67).

Other studies clinically assessing co-occurring disorders in treatment-seeking pathologic gamblers have also noted high estimates of mood disorders (34% to 78%) (43,6870). In 1984, McCormick et al. (68) studied 38 cases of treatment-seeking pathologic gamblers with major depressive disorder and found that, in 86% of cases, the gambling problem preceded the onset of depression. These findings, however, need to be interpreted with caution because the majority of these studies were derived from treatment-seeking pathologic gamblers, which may or may not reflect non–treatment-seeking pathologic gamblers. Yet, they also raise the question of whether co-occurring mood disorders may be secondary to pathologic gambling. A twin study of self-reported family history to estimate shared genetic contributes to pathologic gambling and major depression in men (71), however, suggests a possible shared biologic predisposition to the co-occurrence of the disorders.

High prevalence estimates of co-occurring anxiety disorders (28% to 40%) also exist in pathologic gamblers (65,69), but not all anxiety disorders are seen with equal frequency (72). Research suggests that estimates of co-occurring generalized anxiety disorder range as high as 40% among pathologic gamblers (62), whereas those of obsessive–compulsive disorder may be as low as 1% (1). The relationship of obsessive–compulsive disorder to pathologic gambling, however, has produced a mixed picture, with some studies reporting high estimates (17% to 20%) (64,65) and other investigations generating low estimates (1%) (62). The rates of co-occurring disorders often have wide ranges, and this may be owing to lack of structured clinical interviews used in assessing comorbidity, the small sample sizes of gamblers assessed, sample selection, and the possible heterogeneity of pathologic gambling.

Significantly fewer data are available regarding the frequencies of Axis II personality disorders in pathologic gamblers. Studies have shown that estimates of any personality disorder in pathologic gamblers range from 25% to 93% (69,7375). Borderline (3% to 70%), narcissistic (5% to 57%), avoidant (5% to 50%), and obsessive–compulsive (5% to 59%) personality disorders are most commonly reported (69,7375). One of the best studied personality disorders in pathologic gambling, antisocial personality disorder, has been found in 15% to 40% of pathologic gamblers, a frequency higher than the 0.6% to 3% estimates reported for the general population (76,77). Although multiple reasons may explain the elevated rates of a comorbid antisocial personality disorder in pathologic gambling, evidence from past studies suggests a possible shared genetic vulnerability between pathologic gambling and antisocial personality disorder (78).

Family History

High frequencies of psychiatric disorders are seen in the first-degree relatives of those with pathologic gambling. Commonly reported conditions include mood, anxiety, substance use, and antisocial personality disorders (47,79,80). In two studies of first-degree relatives of pathologic gamblers, 17% to 33% had a mood disorder, and 18% to 24% reported an alcohol use disorder (65,79). In another study of 51 pathologic gamblers, 50% had a parent with an alcohol use disorder (80). A large sample of 517 pathologic gamblers revealed that subjects with at least one problem gambling parent were significantly more likely to have a father with an alcohol use disorder, report daily nicotine use, and have significantly worse legal and financial problems compared to the cohort without a problem gambling parent (81).

Studies have also found that 20% of the first-degree relatives of pathologic gamblers also have pathologic gambling (82). Recent research examining possible familial aggregation of pathologic gambling found that individuals with a problem gambling parent were at a 3.3 times higher risk of being a pathologic gambling (83). Similarly, Gambino et al. (84) found that problem gamblers at a Veterans Affairs hospital were up to eight times more likely to have a parent with a gambling problem than were nonproblem gamblers. In one of the few studies to use a psychometrically sound instrument (Family History Research Diagnostic Criteria) to collect family history data, the researchers found that 31% of first-degree relatives of pathologic gamblers had a lifetime alcohol use disorder and 19% had lifetime major depressive disorder (47).

In one of the few studies to use a control group to examine familial aggregation of psychiatric disorders among pathologic gamblers, Black et al. (85) examined 31 patho-logic gambler probands and 31 control probands. Lifetime estimates of pathologic gambling were significantly higher in family members of pathologic gamblers (8.3%) compared to control subjects (2.1%) (odds ratio of 4.49; p = 0.018). Similarly, elevated estimates were observed for substance use disorders (odds ratio of 4.21) and antisocial personality disorder (odds ratio of 7.73) (85).

TREATMENT

Psychotherapy

Although there is a long literature of case reports using psychodynamic psychotherapy and psychodynamic psychotherapy is often incorporated into multimodal, eclectic, and integrated approaches to pathologic gambling, there are no randomized controlled trials supporting its use (86). Similarly, although some evidence exists that Gamblers Anonymous (8790) and self-exclusion contracts (9194) may be beneficial for pathologic gamblers, limited and conflicting data assessing the long-term efficacy for these interventions have been published.

A variety of psychosocial treatments have been examined in controlled studies for the treatment of pathologic gambling (95). Cognitive strategies have traditionally included cognitive restructuring, psychoeducation, and irrational cognition awareness training. Behavioral approaches focus on developing alternate activities to compete with reinforc-ers specific to pathologic gambling as well as the identification of gambling triggers. See Table 39-1 for a summary of psychotherapeutic treatments.

TABLE 39-1 CONTROLLED PSYCHOLOGICAL TREATMENT TRIALS

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Assessment of Psychotherapy

Empirical studies of CBT and using various elements, CBT (i.e., cognitive or behavioral therapy, motivational interviewing, and CBT workbooks) support the efficacy of using CBT for pathologic gamblers, because the majority of trials found reductions in pathologic gambling symptomatology compared to the control conditions. However, these trials are insufficient to provide information about the optimal treatment duration and the level of training needed by the therapy administrator. Both brief and longer treatments have been found effective, but no study has randomized subjects into psychotherapeutic treatments of varying durations to determine the most efficacious treatment length. In addition, few studies have long-term follow-up, highlighting the need for future studies to include long-term followup visits to assess maintenance of therapeutic gains.

Furthermore, with the exception of Hodgins et al. (116), few studies provided a detailed description of the content of the therapy sessions or workbook and measurements of therapist adherence and competence. Inclusion of these items would aid in the interpretation and application of study findings, for lack of therapist adherence to study protocol may confound study results. Characteristics of individuals with pathologic gambling who succeed in and do not respond to psychotherapy also need to be investigated. Possible variables that impact individual success as well as treatment adherence may include insight, desire to change, comorbid psychological and physical conditions, and impulsivity.

Pharmacotherapy

No medication is currently approved by the U.S. Food and Drug Administration for treating pathologic gambling. Seventeen randomized, placebo-controlled trials of phar-macotherapy treatment in pathologic gambling have been conducted, and these studies suggest that medications may be beneficial in treating pathologic gambling. See Table 39-2 for a summary of pharmacotherapeutic treatments.

TABLE 39-2 CONTROLLED PHARMACOTHERAPEUTIC TREATMENT TRIALS

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Assessment of Pharmacotherapy

Due to the promising results of the double-blind trials of naltrexone and nalmefene, opioid antagonists appear to be the most efficacious pharmacologic treatment for pathologic gambling and should be considered a first-line treatment for pathologic gambling. However, similar to the nalmefene, empiric trials of naltrexone should be conducted at additional research sites to examine the efficacy of naltrexone in varying patient populations. Results from trials investigating the glutamate modulator, N-acetylcysteine, and lithium suggest these medications may also be effective, but with only one trial completed for each, additional research is needed to bolster support. Antidepressants have been the most widely examined with findings providing indefinite results, yet for individuals with high anxiety, escitalopram may be an effective treatment. Currently, no evidence supports the use of atypical antipsychotics.

More research is needed to determine the most effective dosage of each medication. Currently, only two studies (125,126) assessed the differential impact of various dosages. Also unevaluated is the long-term impact of these medications, with only two studies (127,129) assessing the phar-macologic treatment effect for longer than 6 months. One challenge in pursuing these data is that studies historically have higher dropout rates (44% to 59%) (127,129).

Understanding clinical and demographic variables may also help clinicians find the most efficacious treatments. Individuals with intense gambling urges may respond better to naltrexone (123), and males and younger individuals with pathologic gambling may respond well to fluvoxamine (129). There are limited data concerning the efficacy of phar-macotherapy for individuals with pathologic gambling and a comorbid psychiatric disorder. Preliminary findings suggest that individuals with pathologic gambling and bipolar disorder may respond best to lithium (135), while those with comorbid anxiety may find relief with escitalopram (132). These findings suggest that investigating the clinical characteristics of individuals who positively respond (as well as those who do not respond) to treatment is necessary. In addition, no randomized, placebo-controlled studies have been completed comparing pharmacotherapy treatments or comparing pharmacotherapy to psychotherapy. These trials would provide insight into which individuals may respond best to a certain class of medication or psycho-therapeutic treatment.

Treatment Recommendations

Pathologic gambling is a common, disabling psychiatric disorder that is associated with high rates of co-occurring disorders, particularly substance use disorders, and high rates of illegal activities. Psychotherapy and pharmacotherapy have shown promise in the treatment of pathologic gambling. Based on the treatment literature, the off-label trials of naltrexone would appear the most promising pharmacologic option for a working clinician. A selective serotonin reuptake inhibitor antidepressant used off-label may also be beneficial particularly when the individual has comorbid depression or anxiety.

In terms of psychosocial treatments, cognitive–behav-ioral therapy appears promising. There are several manu-alized forms of this therapy (108,109,139141). Although the stronger evidence suggests that eight sessions of CBT should be considered (88), some data suggest that even fewer sessions (107,136) or brief interventions (95) may be effective. With a manualized treatment, counselors with a background in addiction medicine should be able to deliver the treatment with minimal training.

Even knowing the evidence for various treatment options for pathologic gambling, other factors may influence which treatment option is chosen for a particular patient. First, many clinicians are simply unaware of pathologic gambling. Therefore, if a clinician is referring a patient for either medication management or psychotherapy, it may simply be difficult to find people who know how to treat the behavior. This problem can be minimized by having a list of providers who know about pathologic gambling and can provide treatment. For example, if no one is available to do CBT for pathologic gambling, then perhaps medication management should be first.

Second, there are no clear recommendations of treatment for the clinician to follow. For example, it is unclear exactly how many sessions of CBT are most helpful for pathologic gambling. The exact dose of medication or duration of medication trial for optimal treatment is also unknown. These gaps in knowledge make it difficult to inform patients about what their care may entail and what expectations they may have.

Third, individuals with pathologic gambling exhibit high rates of placebo response in treatment studies. Clinicians need to understand that for many patients with pathologic gambling, simply talking about their problem will help substantially at first. This initial robust response, however, may cause the clinician to believe that his or her treatment approach is successful. Clinicians should carefully monitor the patient for several months and not assume they will continue to do well. Also, involving a family member or close friend in treatment efforts who can assist the patient in monitoring his or her behavior and provide accountability may be beneficial for some patients.

Fourth, impulsive patients do not often follow recommendations or follow-up with treatment. The treatment data consistently show that dropout rates are high for pathologic gambling. This may be owing to two factors: One, patients often believe they are doing better than in fact they are and therefore see treatment as unnecessary; and two, they do not have an instantaneous response and therefore do not stay with treatment. Both of these concerns can be minimized by providing psychoeducation about the illness, detailing the expectations of treatment, and the expressing the need to stay in treatment.

CASE STUDY

David is a 39-year-old, single male with a college degree who works full time. He endorses a family history positive for alcohol abuse in his father and paternal grandfather. David reports having started to gamble with friends at the age of 17, with his first trip to casino at 21 years old. In his younger years, he reported gambling only with friends, playing poker, blackjack, and slot machines. He would frequent the casino once every couple of months.

At the age of 30, David was promoted to a position with more responsibility and experienced much higher levels of stress at work. Since the casino had been fun for him in the past, he decided to visit the casino on a Friday night after a particularly stressful week. David played the slot machines and found it relaxing. On this night, he actually won $100 USD from playing and walked away from the casino feeling less stress and happy.

Over the coming weeks, however, David began to frequent the casino in the middle of the week, having nearly constant urges to gamble, especially when his work became stressful. He began to stay at the casino late into the night and show up late or tired for work the following morning. His work began to suffer, and David was reprimanded by his bosses for his lowered productivity. This added stress prompted David to return to the casino where he had experienced stress relief before. On one occasion, he stayed for 26 hours straight and lost $1,700 USD, resulting in his missing work the next day and an inability to pay his bills. With his finances out of control and feeling helpless, David decided he needed help.

David called a psychologist specializing in addiction treatment. He started a regimen of individual, weekly CBT with imaginal desensitization and focus on stress management. David reported, however, that his urges to gamble were nearly constant, making it difficult for him to focus on the CBT homework. Given his intense urges coupled with a family history of alcohol abuse, he was prescribed naltrexone 50 mg/d. After 2 weeks, David reported that his urges to gamble decreased significantly and he was able to focus on CBT paradigm.

After 8 weeks of therapy and naltrexone treatment, David reported only gambling once and feeling much more able to handle stress in the workplace. He scheduled maintenance CBT sessions with his therapist and psychiatrist each month to reinforce the CBT skills learned and manage his now-minimal urges. At a 1-year follow-up, David had only gambled three times and reported feeling much more in control of his gambling and life.

Acknowledgments

This research was supported in part by an American Recovery and Reinvestment Act (ARRA) grant from the National Institute on Drug Abuse (1RC1DA028279-01) and a Center for Excellence in Gambling Research grant by the National Center for Responsible Gaming (NCRG).

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