Diagnosis and treatment of pathologic gambling

Longitudinal subtypes of disordered gambling in young adults identified using mixed modeling

OBJECTIVE

While many individuals gamble responsibly, some develop maladaptive symptoms of a gambling disorder. Gambling problems often first occur in young people, yet little is known about the longitudinal course of such symptoms and whether this course can be predicted. The aim of this study was to identify latent subtypes of disordered gambling based on symptom presentation and identify predictors of persisting gambling symptoms over time.

METHODS

575 non-treatment seeking young adults (mean age [SD] = 22.3 [3.6] years; 376 (65.4%) male) were assessed at baseline and annually, over three years, using measures of gambling severity. Latent subtypes of gambling symptoms were identified using latent mixture modeling. Baseline differences were characterized using analysis of variance and binary logistic regression respectively.

RESULTS

Three longitudinal phenotypes of disordered gambling were identified: high harm group (N = 5.6%) who had moderate-severe gambling disorder at baseline and remained symptomatic at follow-up; intermediate harm group (19.5%) who had problem gambling reducing over time; and low harm group (75.0%) who were essentially asymptomatic. Compared to the low harm group, the other two groups had worse baseline quality of life, elevated occurrence of other mental disorders and substance use, higher body mass indices, and higher impulsivity, compulsivity, and cognitive deficits. Approximately 5% of the total sample showed worsening of gambling symptoms over time, and this rate did not differ significantly between the groups.

CONCLUSIONS

Three subtypes of disordered gambling were found, based on longitudinal symptom data. Even the intermediate gambling group had a profundity of psychopathological and untoward physical health associations. Our data indicate the need for large-scale international collaborations to identify predictors of clinical worsening in people who gamble, across the full range of baseline symptom severity from minimal to full endorsement of current diagnostic criteria for gambling disorder.

Down-regulation of serotonin and dopamine transporter genes in individual rats expressing a gambling-prone profile: A possible role for epigenetic mechanisms

Gambling Disorder (GD) is characterized by excessive gambling despite adverse consequences on individual functioning. In spite of some positive findings, it is difficult to draw any conclusion on the genetics of GD. Indeed, beyond DNA sequence variation, other regulatory mechanisms (like those that engage epigenetics) may explain gene alterations in this addictive disease. Wistar male rats underwent an operant task for the evaluation of individual propensity to gamble. Few rats, after having learnt to prefer nose-poking for a large over a small food reward, were sacrificed to obtain a baseline profile of gene expression at both central and peripheral levels. In the remaining rats, probability of occurrence of large-reward delivery decreased progressively to very low levels. Thus, rats were faced with temptation to "gamble", i.e. to nose-poke for a binge reward, whose delivery was omitted the majority of times. After 3weeks of testing, rats showing a clear-cut profile of either gambling proneness or aversion were selected and sacrificed after the last session. A selective down-regulation of i) serotonin transporter in prefrontal cortex, ii) tyrosine hydroxylase in ventral striatum, iii) dopamine transporter in lymphocytes was evidenced in "gambler" vs "non-gambler" rats. The exposure to such operant task (compared to home-cage alone) modulated ventrostriatal but not prefrontal genes. A consistent increase of DNA methylation, in one specific CpG site at serotonin transporter gene, was evident in prefrontal cortex of "gambler" rats. Elucidation of epigenetic changes occurring during GD progression may pave the way to the development of new therapeutic strategies through specific modulation of epigenetic factors.

SCRATCH THAT!—Two case reports of scratch-card gambling disorder

Gambling disorder is a common, clinically relevant condition that impacts significantly one's life. Given that approved pharmacological interventions are lacking, it is crucial to readily identify these cases to provide available interventions in psychiatric care services. Here, we present two uncommon cases of unique scratch-card gambling disorder, a specific type of pathological gambling that could be increasing as availability of these games are growing.

Pharmacotherapy of pathological gambling: review of new treatment modalities

Pathological gambling is classified in the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition as an impulse-control disorder. In the International Classification of Diseases of the WHO, pathological gambling is coded under the heading of 'Habit and Impulse Disorders'. Pathological gambling is a chronic, progressive disorder, which has a prevalence of 1-3.4% among western civilizations. The enormous personal and social consequences of this disorder include a high rate of suicide attempts, job loss, marital and family problems, legal problems, and criminal behavior. Recent studies have demonstrated that pathological gambling patients respond well to treatment with selective serotonin reuptake inhibitors, mood stabilizers and opioid antagonists. These findings support the idea that pathological gambling and other disorders of impulse control may be conceptualized as part of the obsessive-compulsive spectrum disorders or addictive disorders. This article will discuss possible treatment strategies according to different behavior patterns in pathological gambling and also remind the physicians who intend to treat this disorder of the possible diagnosis of pathological gambling.

A double-blind, placebo-controlled trial of topiramate for pathological gambling

OBJECTIVES

Pathological gambling (PG) is an impulse control disorder characterized by recurrent gambling thoughts and behaviours that impair social functioning. Earlier studies suggested that topiramate may be effective in treating some impulse control disorders. We conducted the first randomized, controlled trial of topiramate in PG.

METHODS

PG patients were randomized to topiramate (N = 20) or placebo (N = 22) in this 14-week, double-blind, placebo-controlled, parallel-group trial. The primary outcome measure was change in the obsessions subscale of the Yale-Brown Obsessive-Compulsive Scale Modified for Pathological Gambling.

RESULTS

Mixed regression models (time [weeks] × treatment) revealed no significant treatment effect of topiramate on the primary or secondary outcome measures. The most statistically robust findings involved reducing the Barratt Impulsiveness Scale (BIS) total score and Motor and Non-Planning subscale scores, for which topiramate outperformed placebo at merely a trend level (P < 0.1).

CONCLUSIONS

The observed trend in BIS score reductions may warrant further investigation to study whether topiramate reduces clinically important impulsivity in PG. Treatment studies with larger samples and less stringent exclusion criteria are needed to produce results that can be generalized to pathological gamblers in the community.

Pathological gambling: a review of phenomenological models and treatment modalities for an underrecognized psychiatric disorder

Pathological gambling (PG) is a prevalent and highly disabling impulse-control disorder. Two dominant phenomenological models for PG have been presented in the literature. According to one model, PG is included as an obsessive-compulsive spectrum disorder, while according to the second model, PG represents a form of nonpharmacologic addiction. In this article, we present an expanded conceptualization of the phenomenology of PG. On the basis of our clinical research experience and a review of data in the field, we propose 3 subtypes of pathological gamblers: the "impulsive" subtype, the "obsessive-compulsive" subtype, and the "addictive" subtype. We also review the current pharmacologic and nonpharmacologic treatment strategies for PG. A further aim of this article is to encourage awareness of the importance of improved screening procedures for the early detection of PG.

Social withdrawal and gambling-like profile after lentiviral manipulation of DAT expression in the rat accumbens

Dysfunction of brain dopamine transporter (DAT) has been associated with sensation seeking and impulse-control disorders. We recently generated a new animal model by stereotaxical inoculation of lentiviral vectors, which allowed localized intra-accumbal delivery of modulators for DAT gene: GFP (green fluorescent protein) control, silencers (Sil), a regulatable enhancer (DAT+), or both (DAT+Sil). Wistar male rats were followed both for socio-emotional profiles and for propensity to seek risky, uncertain rewards. Elevated anxiety and affiliation towards an unfamiliar partner emerged in Sil rats. Interestingly, in DAT+Sil rats (and Sil rats to a lesser extent) levels of playful social interaction were markedly reduced compared to controls. These DAT+Sil rats displayed a marked 'gambling-like' profile (i.e. preference for a large/uncertain over a small/sure reward), which disappeared upon doxycycline-induced switch-off onto DAT enhancer, but consistently reappeared with doxycycline removal. MRI-guided 1H-MRS (at 4.7 T) examinations in vivo (under anaesthesia) revealed changes in the bioenergetic metabolites (phosphocreatine and total creatine) for DAT+Sil rats, indicating a functional up-regulation of dorsal striatum (Str) and conversely a down-regulation of ventral striatum (i.e. nucleus accumbens, NAc). A combined profile of (1) enhanced proneness to gambling and (2) strong social withdrawal is thus associated with altered DAT-induced balance within forebrain dopamine systems. In fact, risk of developing a gambling-prone, social-avoidant psychopathology might be associated with (1) dominant semi-automatic strategies and/or habits, developed within Str circuits, and (2) reduced NAc function, with poorer feedback adjustment on decisions by aversive experiences.

Neurological considerations: autism and Parkinson's disease

Within the spectrum of disorders that manifest obsessive-compulsive (OC) features lies a sub-cluster of neurological conditions. Autism and Parkinson's disease (PD) are examples of two such neurological disorders that seem quite dissimilar on the surface. Yet, both conditions can include repetitive behaviors of a compulsive-impulsive nature. Furthermore, while autism and PD differ in other associated symptom domains that shape the course of each disorder, both disorders share some phenomenology in the core domain of repetitive behaviors and involve basal ganglia and frontal lobe dysfunction, similar to OC disorder (OCD). Accordingly, examination of the similarities and differences between autism and PD may provide insight into the pathophysiology and treatment of OC spectrum disorders. The current review focuses on the phenomenology, comorbidity, course of illness, family history, brain circuitry, and treatment of autism and PD, as they relate to OCD and OC spectrum disturbances.

Increased impulsive behavior and risk proneness following lentivirus-mediated dopamine transporter over-expression in rats' nucleus accumbens

Multiple theories have been proposed for sensation seeking and vulnerability to impulse-control disorders [Zuckerman M, Kuhlman DM (2000) Personality and risk-taking: Common biosocial factors. J Pers 68:999-1029], and many of these rely on a dopamine system deficit. Available animal models reproduce only some behavioral symptoms and seem devoid of construct validity. We used lentivirus tools for over-expressing or silencing the dopamine transporter (DAT) and we evaluated the resulting behavioral profiles in terms of motivation and self-control. Wistar adult rats received stereotaxic inoculation of a lentivirus that allowed localized intra-accumbens delivery of a DAT gene enhancer/silencer, or the green fluorescent protein, GFP. These animals were studied for intolerance to delay, risk proneness and novelty seeking. As expected, controls shifted their demanding from a large reward toward a small one when the delivery of the former was increasingly delayed (or uncertain). Interestingly, in the absence of general locomotor effects, DAT over-expressing rats showed increased impulsivity (i.e. a more marked shift of demanding from the large/delayed toward the small/soon reward), and increased risk proneness (i.e. a less marked shift from the large/uncertain toward the small/sure reward), compared with controls. Rats with enhanced or silenced DAT expression did not show any significant preference for a novel environment. In summary, consistent with literature on comorbidity between attention-deficit/hyperactivity disorder and pathological gambling, we demonstrate that DAT over-expression in rats' nucleus accumbens leads to impulsive and risk prone phenotype. Thus, a reduced dopaminergic tone following altered accumbal DAT function may subserve a sensation-seeker phenotype and the vulnerability to impulse-control disorders.

Pharmacological treatments of pathological gambling

Medication treatment studies have demonstrated short-term efficacy of various SRIs, opioid antagonists, and mood stabilizers in sub-samples of adult treatment seeking pathological gamblers. Pathological gambling is frequently comorbid with bipolar spectrum disorders, substance abuse/dependence, and attention-deficit/hyperactivity disorder (ADHD), and comorbidity may influence treatment response in pathological gambling. This review focuses on recent research examining the treatment of pathological gambling and highlights methodological challenges for future studies.

Comorbidity issues in the pharmacological treatment of Pathological Gambling: a critical review

Background

Pathological Gambling (PG) is an impulse control disorder often comorbid with other psychopathology, particularly bipolar spectrum disorders, attention deficit/hyperactivity disorder, obsessive-compulsive disorder (OCD) and substance abuse. This paper reviews the published literature on the pharmacological management of PG, highlighting how clinical and subclinical comorbid psychopathology influences the choice of pharmacological treatment.

Methods

Using Medline, the authors reviewed relevant articles published on this topic from1995 to 2005, focusing on the best-designed studies for inclusion.

Results

Much of the literature on PG-treatment presupposes different theories regarding this disorder. Data suggest the utility of differentiating the pharmacotherapy of pathological gamblers in light of their comorbid profile, specifically assessing for comorbid bipolar, ADHD, OCD, and substance abuse disorders.

Conclusion

Decisions about pharmacological treatment of PG should take into account current and previous comorbid disorders which influence treatment selection.

Pathological gambling: a comprehensive review of biobehavioral findings

In this review, findings of biobehavioral research into pathological gambling (PG) are discussed, focusing on neuropsychological, psychophysiological, neuroimaging, neurochemical and genetic studies. Neuropsychological studies indicate deficiencies in certain executive functions. Psychophysiological studies indicate that arousal in PG is of importance when reward is present. Neuroimaging studies point to abnormalities in brain functioning. Recent research into the neurochemistry of PG indicates that abnormalities exist in different neurotransmitter systems. Finally, genetic studies indicate the existence of abnormal dopamine receptor genes in PG. Methodological and theoretical factors that may explain discrepancies between studies include differences in screening and assessment, heterogeneity of gambling problems and different underlying cognitive or motivational mechanisms. Results from the PG studies fit in with recent theoretical models of addiction and PG, which stress the involvement of brain reward pathways, neurotransmitter abnormalities, the frontal cortex and the psychophysiological stress system. A framework for future studies is suggested, indicating the need for studies that integrate knowledge from different research areas, and that employ stricter diagnostic screening methods and inclusion of clinical control groups.