Features of Gambling Disorder and Internet Gaming Disorder in the spectrum of addictive disorders

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Thesis

Reference

Features of Gambling Disorder and Internet Gaming Disorder in the spectrum of addictive disorders

ACHAB, Sophia

Abstract

It might be hard to imagine that a leisure activity could turn to suffering and mental disorder in need of treatment. Nevertheless, emergent behavioral addictions (BAs) such as gambling disorder (GD) and Internet use disorders (e.g., Internet gaming disorder [IGD) have become common treatment-seeking motives in dedicated facilities and a flourishing field for research.

These recent entities and their similarities to substance use disorders (SUDs) have raised debate in the scientific community and among clinicians. A major resulting revolution is that the addictive spectrum has recently been enlarged to include addictions that do not require the intake of a psychoactive substance. This inclusion has sparked debate on addiction determinism and whether neurobiological processes could be involved in repetitive exposure to a substance, as well as in cognitions and behaviors. A core clinical addiction syndrome can be extracted by comparing recent diagnostic criteria for SUDs in the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5; American Psychiatric Association [APA], 2013) with those for the two [...]

ACHAB, Sophia. Features of Gambling Disorder and Internet Gaming Disorder in the spectrum of addictive disorders. Thèse de privat-docent : Univ. Genève, 2016

DOI : 10.13097/archive-ouverte/unige:89231

Available at:

http://archive-ouverte.unige.ch/unige:89231

Disclaimer: layout of this document may differ from the published version.

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Clinical Medicine Section Department of Psychiatry Addiction Division

Features of Gambling disorder and Internet gaming disorder in the spectrum of addictive

disorders

Thesis submitted to the Faculty of Medicine of the University of Geneva

for the degree of Privat-Docent by

Dr. Sophia ACHAB GENEVA

2016

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1

Summary

It might be hard to imagine that a leisure activity could turn to suffering and mental disorder in need of treatment. Nevertheless, emergent behavioral addictions (BAs) such as gambling disorder (GD) and Internet use disorders (e.g., Internet gaming disorder [IGD) have

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3 become common treatment-seeking motives in dedicated facilities and a flourishing field for research.

These recent entities and their similarities to substance use disorders (SUDs) have raised debate in the scientific community and among clinicians. A major resulting revolution is that the addictive spectrum has recently been enlarged to include addictions that do not require the intake of a psychoactive substance. This inclusion has sparked debate on addiction determinism and whether neurobiological processes could be involved in repetitive exposure to a substance, as well as in cognitions and behaviors.

A core clinical addiction syndrome can be extracted by comparing recent diagnostic criteria for SUDs in the Diagnostic and Statistical Manual of Mental Disorders (5th ed.;

DSM-5; American Psychiatric Association [APA], 2013) with those for the two considered BAs: GD and IGD. Clinical, psychological, and neurobiological differences and similarities between BAs and SUDs are reviewed and discussed in the present work. Critical links are made between these scientific findings and recent DSM-5 criteria.

A full picture of the magnitude of BAs remains imprecise because of several methodological limitations, a lack of standardized screening tools being the major obstacle.

We present a recent study (Appendix 4) that we conducted to test the factorial structure of the most commonly used screening tool in which we made some psychometric enhancement proposals. We also presented the relevance of this screening tool for online GD and IGD.

The research complexity (financial, ethical, and technical, as well as access to targeted samples) of this field is illustrated by the paper on IGD (Appendix 1). Our results nevertheless contribute to a better understanding of this disorder. High prevalence rates of IGD were found among gamers, and the impact of IGD on social functioning, health, and emotional states was self-reported in a representative adult gamer population. Withdrawal and

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4 tolerance symptoms in gaming activity were also self-reported, lending an additional link to SUDs.

Neuro-functional and cognitive processes involved in GD have been reviewed (Appendix 2) to offer a better understanding of the development and evolution of GD from a neural, environmental, behavioral, and psychological perspective. Such a perspective will have therapeutic applications in the treatment of patients with these disorders, in consideration of the interconnection between biology, psyche, and behavior. The interactive relationship between clinical practice and research is vital to bring light to the phenomenological understanding of mental disorders. This is also the case for GD and IGD, with a need for a multivariate outlook that leads to a rich, multidimensional, comprehensive definition.

To improve the early detection of and intervention in BAs and to reduce the impact of treatment delay on patients and their environment, preclinical efforts are a promising field of action in which to invest. A willingness and readiness of primary care to be part of this effort for GD is discussed in the present work (Appendix 3), with some interesting perspectives such as tailored information and training.

The treatment strategy most commonly used in BAs is psychotherapy. Nevertheless, pharmacological approaches should be explored to alleviate suffering in patients who have BA or related disorders. We hereby present an overview of effective and promising drugs tested in clinical trials (Appendix 5) in order to help clinicians choose therapeutic options and to help researchers explore promising avenues of investigation.

The field of BAs offers numerous and promising perspectives in development and research. We present some of our blueprints on the conceptualization and recognition of BAs (i.e., GD and IGD), vulnerability factor identification, detection and diagnosis, and care response.

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5 The application of a public health framework to BAs is a challenging step in order to fill the gap between individual support and a national and global strategy of harm reduction and care management. It needs to integrate many more parameters than those of a health system, as it must deal with contextual factors (e.g., law, economics, and culture

I. Introduction

Leisure moments generally consist of engaging in pleasurable and relaxing activities.

Sometimes passion can become a source of loss of control that generates complaints from individuals or their relatives. This has been the case in recent decades for gambling, gaming, and Internet use, bringing out societal and scientific concern about the detrimental pattern of engagement in these recreational activities.

Problematic engagement in leisure activities such as gambling, gaming, and Internet use presents symptoms that are similar to those of SUDs, e.g., repetitive and automatic engagement with loss of control, continuation despite negative consequences, continuous preoccupation, and even reported withdrawal symptoms (Yau & Potenza, 2015). This similar clinical picture to addictive disorders has in some cases brought individuals affected by related psychosocial consequences, as well as their relatives, to seek help and information for an addiction-like disorder (Thorens et al., 2014a). The observation of symptomatic closeness to SUDs has led professionals to use a new term, behavioral addictions, and the scientific community has had to adapt since the nineties to the emergence of a new research topic, while the medical community had to adapt to new treatment requests.

Questions arising in this context were many. Can passion turn into addiction? Is an individual report sufficient to consider an unknown disorder? Should the addictive spectrum include nonchemical or behavioral addictions? Where should the cutoff be between

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6 physiological and pathological engagement? What should the therapeutic approach be? What is the extent of the issue in the population and how can it be measured? Are there public health consequences of such disorders and how should the authorities regulate the risks?

In this introductory section, we present epidemiological challenges of GD and IGD. We also introduce and discuss recent conceptual changes in the addictive spectrum.

1. Epidemiological issues

1.1. Gambling disorder (GD)

The epidemiological data worldwide yielded a past-year prevalence of problem gambling ranging from 0.5% to 7.6% (Williams, Volberg, & Stevens, 2012). The average rate across all countries was 2.3%, with the highest prevalence rates found in Asia, the lowest rates in Europe, and intermediate rates in North America and Australia (Williams, et al., 2012).

Differences in prevalence rates are partly explained by different tools used to screen for GD in different samples.

In Switzerland, the life-time prevalence for pathological gambling in 2005 was 1.1% and for problem gambling (fewer criteria fulfilled) was 2.2% in the general population over 18 years old (Bondolfi, Jermann, Ferrero, Zullino, & Osiek, 2008)..In a sample of young male adults, the prevalence of problem gambling was 1.4% (Tomei, Tichelli, Ewering, Nunweiler- Hardegger, & Simon, 2015) and the prevalence of at-risk gambling in adolescents was 5.5%

(Tozzi, Akre, Fleury-Schubert, & Suris, 2013). GD has been validated by screening and diagnostic tools for decades. This validation has facilitated broad epidemiological surveys and provided data on problematic and excessive gamblers at a global level.

Problem gambling shares its natural course with that of SUDs, with the chronic course comprising relapse and remission periods (Yau & Potenza, 2015). It highly co-occurs with

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7 other mental disorders (i.e., 60.1% with nicotine dependence, 57.5% with SUDs, 37.9% with mood disorders, and 37.4% with anxiety disorders) (Lorains, Cowlishaw, & Thomas, 2011).

These psychiatric disorders were preexistent to GD, but incident anxiety and mood disorders have also been found during the course of GD in longitudinal designs (Yau & Potenza, 2015).

1.2. Internet gaming disorder (IGD)

Regarding epidemiological data on IGD, with the lack of a gold standard or consensus on its definition, studies have mainly focused on Internet-related disorders (including video gaming and social networking). Most studies targeted adolescents and young adults, using different methodologies and screening tools to yield widely disparate prevalence rates ranging from 0.7% to 42 %, the highest rates being found in Asia (Achab, Meuli, et al., 2014). The main data that could be extracted from such an uninformative wide range showed that by examining screening tools used worldwide, one can extract their underlying concepts. The global trend in identifying Internet-related disorders seems to uniformly be the addiction concept for American studies, while many conceptual models (i.e., addiction, pathological use, compulsive use, and excessive use) have been used for Europe and Asia, with more conceptual variation across European countries (Achab, Meuli, et al., 2014).

In Switzerland, a national survey conducted in 2013 found problematic Internet use in 3.7%

of the general population, with adolescents presenting higher rates (6.5%) and IGD being present in 3.1% of the sample aged 15-34 years (Marmet, Notari, & Gmel, 2013).

Internet-related disorders have been reported to be associated with impaired social and professional functioning, as well as with comorbid mental and physical disorders (Achab et al., 2015). IGD has been associated with poorer academic performance, family conflicts, reduced leisure activities and interests, and psychiatric disorders (mostly depression, anxiety, SUDs, and attention deficit hyperactivity disorder [ADHD]) (Achab et al., 2011; Achab, et al.,

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8 2015). Excessive use of the Internet and of electronic devices has been found to be linked to physical issues (e.g., musculoskeletal, sleep, weight, and vision) (Chung, 2014). Most patients (68%) treated for IGD have also been diagnosed with a concurrent psychiatric condition, with only 39% ever having benefited from psychiatric treatment (Thorens, et al., 2014a). Anxiety disorder, mainly social phobia, was the most frequent concurrent diagnosis (26%), followed by psychosis and SUDs (equally present in 11% of patients), mood disorders (7.2%), ADHD (7.1%), personality disorders (5.4%), and mental retardation (1.8%) (Thorens, et al., 2014a).

2. Recent changes in the addictive spectrum

2.1. Non-Substance-Related Disorders officially begin to be part of addictive disorders A major conceptual change occurred in the field of addiction medicine in recent decades, calling for the framework of addictive disorders to be widened by exempting a psychoactive product as the inclusive condition (Martinotti, Corazza, Achab, & Demetrovics, 2014). The historical culmination of this change was the inclusion of a new category, “Non-Substance- Related Disorders, in the new “Substance-Related and Addictive Disorders” of the DSM-5 in 2013(American Psychiatric Association, 2013). Pathological gambling has reached the scientific data milestone that allowed it to be considered a “gambling disorder” within addictive disorders as a Non-Substance-Related Disorder. This decision was supported by research in recent decades that provided evidence about its closeness to SUDs in terms of physiology, brain origins, comorbid conditions, therapeutic approaches and clinical expression (Yau & Potenza, 2015). Although a set of criteria for “Internet gaming disorder”

was proposed in DSM-5 and provision of more scientific evidence encouraged, other Internet- related disorders (e.g., social networking, pornography) were not considered at all as potential candidates in the addictive spectrum (Martinotti, et al., 2014). Nevertheless, the shift in this conceptualization is of importance because of the formal recognition of BA as a neurobiological and clinical entity.

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9 2.2. Addiction syndrome as part of SUDs and BAs

This nomenclature revolution also assumes that addiction is now considered a syndrome, that could have various clinical expressions involving the intake of a psychoactive substance or not.

The core syndrome can be extracted from the new classification in the DSM-5 (American Psychiatric Association, 2013) by comparing diagnostic criteria applied to substance use disorders (SUDs) and to gambling disorder (GD) and from those proposed for Internet gaming disorder (IGD). The common diagnostic criteria considered for the three entities in the DSM-5 (American Psychiatric Association, 2013) are (a) unsuccessful attempts to cut down, (b) loss of significant relationships or professional opportunities, (c) tolerance, and (d) withdrawal symptoms. Continuation despite adverse consequences seemed to be set aside from the addiction syndrome, since it is considered in the DSM-5 for SUDs and IGD but, curiously, not for GD.

Different clinical expressions of this addiction syndrome have been considered in the DSM-5 for the three addictive disorders. They are reflected in the specific criteria that have been chosen to be representative of each. We present them below and discuss their selection as criteria that are able to set boundaries between SUDs, GD, and IGD.

2.3. Benefits for addictive disorders from the integration of BAs

In fact, BA offers the opportunity to study neuropsychological and neurobiological processes involved in addiction. Identifying addictive markers is made possible by without the confusing acute and chronic harmful drug effects on the brain that are labeled neurotoxicity.

Nevertheless, one main limitation in considering a BA to be immune from effects on the brain lies in disregarding the neurobiological effects of behaviors. Gambling, for example, is associated with cortisol release and sympathetic neural system activation, which both have a

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10 neural impact with repetitive exposure (Clark, 2014). Another limitation in assuming that the absence of an exogenous drug is a guarantee of absence of an impact on brain structure lies in omitting neuroplasticity (i.e., brain-adaptive processes linked to learning) in a repetitive cognitive and behavioral task such as gambling (Clark, 2014). Moreover, smaller brain volumes in the amygdale and hippocampus regions, similar to those observed in SUDs, and reduced integrity of white matter in comparison with that in healthy controls, have recently been described in disordered gamblers (Yau & Potenza, 2015). Neural correlates of GD are extensively reviewed in describing Appendix 2. These neural findings in a non substance- related disorder can bring light to the understanding of SUDs beyond the drug’s effects on the brain.

2.4. Discussing criteria for addictive disorders considered in the DSM-5

2.4.1. Is splitting the body and the mind the right way to distinguish between SUDs and non- SUDs?

An appealing fact when analyzing the new DSM-5 category (American Psychiatric Association, 2013) for addictive disorders is that SUD criteria are mainly oriented toward the product (i.e., the drug) and its physical effects on the excessive repetitive user. On the other hand, for BAs, specific criteria are more based on the individual and the individual’s cognitions (i.e., the item often preoccupied in GD and IGD), emotional coping (i.e., the items often gambles when feeling distressed; and uses gaming to escape or relieve a negative mood), and interpersonal interaction in relation to the problematic behavior (i.e., the items deceived family members, therapists, or others regarding the amount of Internet gaming; and lies to conceal the extent of involvement with gambling).

It seems that for GD and IGD, the manual (American Psychiatric Association, 2013) considers emotional and cognitive processes but not for SUDs, though excessive substance users often use the drug to cope with emotional states (Deleuze et al., 2015; Selby, Anestis, &

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11 Joiner, 2008), are preoccupied by their past or future drug consumption (i.e., preoccupation/anticipation phase of the addiction cycle)(Koob & Le Moal, 2001), and tend to minimize the extent and risks of their consumption (described as an impaired insight or reduced self-awareness)(Moeller et al., 2014). Furthermore, data accumulates on neural correlates of these psychological processes involved in SUDs (Koob & Le Moal, 2001;

Moeller, et al., 2014).

This difference in diagnostic criteria for addictive disorders (i.e., a product-oriented approach for SUDs and an individual-oriented approach for BAs) suggests that the presence of a drug in SUDs places the determinism of the addictive disorder at a biological response level, whereas for BAs such as GD and IGD, the determinism is considered at a mixed level: psychological (e.g., coping, chasing losses, preoccupation) and biological (e.g. tolerance and withdrawal symptoms). This issue has to be addressed further in light of recent conceptual changes in the addiction field.

2.4.2. What is really specific to SUDs?

For SUDs, specific criteria chosen in the DSM-5 consisted of (1) high engagement in drug seeking and consuming or recovering from substance effects, (2) interference with obligations, and (3) drug craving. The distinction made in the DSM-5 between SUDs and BAs based on these criteria is a matter of question.

Considering the high engagement criterion, first, problematic gamblers and gamers spend a large amount of time engaged in seeking opportunities to gamble or to game and in developing strategies and techniques to win money or to reach higher game levels (Billieux et al., 2015; Yau & Potenza, 2015). This reward seeking could be seen as equivalent to drug seeking. Nevertheless, the DSM-5 considered this kind of high engagement for GD but included it as a preoccupation item. Second, excessive gamblers and gamers spend much time

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12 gambling or gaming, often at the expense of other activities (Billieux, et al., 2015; Yau &

Potenza, 2015), and this could be comparable to high engagement in drug consumption.

Finally, they are probably highly engaged in trying to recover from the negative consequences of gambling or gaming (e.g., financial losses, sleep deprivation, and extreme emotional involvement).

It is also hard to admit interference with obligations as a distinctive criterion between SUDs and BAs because problematic gambling and gaming sessions also often interfere with professional, academic, and social obligations (Billieux, et al., 2015; Yau & Potenza, 2015).

Finally, problematic gamblers and gamers are often driven by craving (Yau & Potenza, 2015) to gamble or to game, which is probably related to intense memories of past gambling and gaming experiences or driven by cue-induced urges as for SUDs (Noori, Cosa Linan, &

Spanagel, 2016).

2.4.3. What is really specific to BAs?

In DSM-5 diagnostic criteria, motivational factors are considered for GD (chasing and coping) and IGD (escaping and coping), but not for SUDs. This lack in the SUD clinical diagnosis seems to be in line with the proposal by Rehm et al. (Rehm et al., 2013) for “heavy substance use over time ” being the unique condition required to define SUDs.” This is problematic because defining addictive behaviors by the amount of excessive and continuous drug use and related harms, in addition to being imprecise, neglects the internal driving force of addiction and puts aside the individual’s cognitive and emotional experiences (Saunders, 2013). These individual experiences are associated with drug consumption and excessive gambling and gaming (Deleuze, et al., 2015), and excessive use and involvement has been associated with addiction symptoms and coping strategies (Deleuze, et al., 2015). These

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13 potential positive and negative reinforcing factors could explain the maintenance and relapses of problematic use and constitute a psychotherapeutic target.

Moreover, the main neural systems involved in these motivational processes are the dopaminergic system for reward seeking and the serotoninergic system for emotional regulation for both SUDs and non-SUDs (Potenza, 2006).

The reward pathway is the cornerstone of the hypothesized involvement of the dopaminergic system in addictive disorders. The mechanism is that drugs target the same brain circuitry that mediates natural rewards in a more intense way. Experimental designs showed, for example, a 150% to 300% increase in dopamine in the nucleus accumbens after heroin injection (Wise, Leone, Rivest, & Leeb, 1995) versus a 37% increase for food consumption (Hernandez &

Hoebel, 1988) and a 50% increase for copulatory behaviors (Pfaus et al., 1990). Moreover, when a choice was given between drug and food, a weak proportion of rats preferred the drug to the natural reward (Carroll, Lac, & Nygaard, 1989), supporting the individual vulnerability factor in the development of preference for potential addictive rewards over natural rewards (Cantin et al., 2010).

2.4.4. Why exclude continuation despite adverse consequences of GD criteria?

A recent paper (Clark, 2014) discusses whether BAs involve sufficient rewarding conditions to lead to addiction to the same extent as SUDs if they lack the potent rewarding exogenous drug intake. Response pathways seem to reside in learning biases (e.g., preeminence of positive reward anticipation even after experiencing repetitive negative outcomes), inner vulnerability factors (such as impulsivity traits), and qualitative (e.g., the potency of reinforcing factors associated with the behavior) rather than quantitative rewarding power (Clark, 2014). These pathways could explain the decision-making bias that leads to the pursuit of excessive drug intake or behaviors despite adverse consequences. A multifaceted

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14 impulsivity trait, for example, has been found to be shared by those with GD and SUDs when compared with healthy controls (Clark, 2014). Disordered gamblers have indeed been found to share risky decision-making with alcohol-dependent subjects (Clark, 2014). They also share deficits in response inhibition and the mood-related facet of impulsivity (i.e., urgency) with cocaine-dependent subjects (Clark, 2014). Insensitivity to choice feedback is shared by GD and nicotine-dependent subjects (Clark, 2014). Differences in impulsivity facets have been found between SUDs and GD: alcohol-dependent patients present additional deficits in impulsive action (i.e., response inhibition) and those with GD show greater deficits in impulsive choice (i.e., delay discounting) than do cocaine-dependent subjects (Clark, 2014).

Moreover, high-craving gambling cues have been found to reverse the usual subjective value coding pattern and to be conducive to more impulsive choice (Miedl, Buchel, & Peters, 2014).

IGD have also been found to be linked to high impulsivity traits and to impaired impulsive choices and actions (Robbins & Clark, 2015). The distinction made in the DSM-5 between SUDs and IGD on the one hand and GD on the other regarding these criteria (i.e., continuation despite negative consequences considered for the first two disorders and not considered for the last disorder), however, remains incomprehensible.

2.4.5. What are the specific criteria for GD?

The main illustration of learning biases present in those with GD, which lead to erroneous and risky decision-decision making, is the solid conviction of future wins despite experiencing repeated losses. Gambling is mainly based on hazard-driven monetary rewards.

The human brain tends to erroneously process information under probabilistic conditions.

When estimating their chances of winning, disordered gamblers seem to have stronger beliefs in their irrelevant perceptions than do non-disordered gamblers (Ladouceur et al., 2004). Such cognitive distortions are called gambler’s fallacy and illusion of control. The near-miss effect, for example, is the perception of close wins that the brain processes as if they were wins, even

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15 when objective losses are experienced (e.g., an outcome of two of three fruits in a slot machine) (Clark, 2014). This cognitive distortion can partly explain the failure of the learning process (i.e., absence of extinction of gambling behavior despite repetitive loss experiences) in disordered gamblers. These fallacies have been investigated, through previously reviewed and discussed neuropsychological and neuro-functional designs (Achab, Nicolier, Khazaal, Zullino, & Haffen, 2012), as being responsible for the development, maintenance, and severity of GD. The potent incentive nature of gambling, added to its physiologically arousing intensity, can lead a minority of gamblers to lose control and engage in problematic repeated behavior. They are driven by unsuccessful attempts to apply learning rules (i.e., the more you train, the more you become skilled) to a random activity.

Seeking the “chance” to make an “easy big win” could represent the addictive ingredient (i.e., comparable to neurobiological drug effects) in GD. Accordingly, chasing losses is a specific criterion recently introduced in the DSM-5 to diagnose GD as an addictive disorder.

2.4.6. What are the specific criteria for IGD?

Surprisingly, no specific criterion was considered for potential IGD as part of the addiction spectrum. Video games offer a wide range of rewarding conditions (e.g., skill development, advancement, social recognition, competition) distinct from drugs and from gambling (Billieux et al., 2013).

Reinforcing properties are in some ways similar to gambling reward through variable-ratio schedules (e.g., repetitive actions required to kill monsters under uncertainty for many parameters, such as the moment when the outcome will be achieved, and the weak winning probability of a particularly rare item) (Thorens, Wullschleger, Khan, Achab, & Zullino, 2012).

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16 Salient stimulus triggering of a reward in the brain system in online games could be represented by reinforcing a social interaction that is made possible, anonymous, immediate, and endless by the Internet. Communication, cooperation, acceptance, humor, hierarchy, comparison, and competition opportunities are present in these games (Thorens, et al., 2012).

The kinetics of online games causes the reinforcing factors to be delivered in an addictive scheme. Indeed, salient stimulus presentation follows operant conditioning rules, delivering immediate and continuous rewards (e.g., skills, levels, virtual money) during the character’s advancement (Thorens, et al., 2012). Highly incentive rewards (e.g., rare equipment or access to highly competitive game scenes) are delivered by intermittent reinforcement (Thorens, et al., 2012). High game accessibility and interactivity through Internet technology is facilitating factor for an addictive pattern of use. For a detailed description of game conditioning mechanisms, see the paper by Thorens et al. (Thorens, et al., 2012).

Furthermore, online video games seem to be more likely to lead to problematic use than offline video games (M.D. Griffiths & Meredith, 2009). The specific addictive component (comparable to the product in SUDs) of such games may be delivered through the addictive vector, the Internet.

The temporality of these online games is characterized by their never-ending development, with regular exciting new challenges, appealing graphic environments, and potent and rare skills. Moreover, the Internet has created persistent games that continue to exist and develop even when there are no gamers interacting with them (Bartle, 2003). This phenomenon could partly explain why problematic online gamers are often preoccupied by what is going on in- game even when they cannot connect to the game. This could be an addictive component of these games, leading the gamer to connect to verify whether any changes have occurred during his or her absence (e.g., other gamers’ advancement, the rank evolution of the gamer’s character). This could also be a maintaining factor of problematic use and an obstacle against

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17 remission for addicted gamers. Preoccupation is an item that has been introduced in the proposed criteria for IGD in the DSM-5. Nonetheless, from our point of view, being triggered by thoughts related to game persistence should be an additional specific criterion within IGD diagnostic criteria.

In summary, BAs (i.e., GD and IGD) have contributed to a great extent to a deep change in the conceptualization of the addictive spectrum. A new addiction category (i.e., “Non- Substance-Related Disorders”) has been born (in the classification of mental disorders in the DSM-5) (American Psychiatric Association, 2013). Disorders deserving to be part of it must correspond to strong and valid evidence in favor of their belonging to mental disorders and addictive disorders.

After an overview of the magnitude of the phenomenon and a discussion of conceptual changes and underlying neurobiological and psychological arguments for GD and IGD, the next chapters present our scientific findings (original research and systematic review papers) on the features of GD and IGD (i.e., psychopathological, assessment, and therapeutic) in the spectrum of addictive disorders . Five recently published papers are provided in-extenso at the end of the manuscript (in an appendix). Within the manuscript, they will be presented through a brief introductory paragraph that highlights several aspects. Studying GD and IGD features within the addictive spectrum

In addition to the conceptual evolution of the addictive spectrum, we were interested in our research in studying the differences and similarities between SUDs and BAs and in extracting the specificities of GD and IGD that could have clinical implications.

1. Psychopathology features

We were interested in better understanding the underlying psychological mechanism for both GD and IGD that could help us to understand the psychological conditions under which

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18 these disorders develop in subjects. In the present work, we present two papers that we have published in this area.

1.1 Internet gaming disorder (IGD)

IGD presents a particularity that makes it different from other scientifically studied health issues, in the sense that it is more complex to reach a representative sample to study the disorder’s determinants and to compare healthy users with problematic users. When it comes to leisure and virtual globalized (World Wide Web) settings, recruitment challenges (e.g., the legitimacy of ethical comities in the virtual world and adapted advertising strategy) are likely to occur. This explains some methodological biases in the available data on IGD, for example, as studies mainly target young samples of university or college students or general Internet users.

The present work on IGD (Achab, et al., 2011) was an online pilot study conducted in 2009 after 3 years of addressing different challenges (i.e., financial, ethical, technical, and specific attractiveness to online video gamers). Regarding the financial aspect, IGD was not at that time a health priority for clinical research support, and the project failed to be supported by any public or private sponsor that we sought. To fulfill ethical rules, we submitted guaranties to the National Commission on Informatics and Liberty (e.g., anonymity, national citizen inclusion, no minor participants, online database security, electronic information and consent forms, and participant’s agreement to use partial data). Technical obstacles (i.e., using an Internet vector for the inclusion procedure that was supposed to develop a dedicated website) were fixed through free web design work by a member of the gamers’ community.

This work also positively contributed to the study’s attractiveness (i.e., similar graphics to that in the environment of the game Heroic Fantasy). The survey received the guilds’ (gamers’

groups) support to advertise the web link, to interview gamers on the best recruitment

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19 procedure, to test gamers’ responsiveness, and to recruit the most representative sample of gamers possible.

The study aimed to collect specific psychopathological data in an adult representative sample of Internet video gamers who were experiencing addictive patterns of use and to compare psychological and socio-demographic data between problematic and non- problematic online video gamers.

For study methodology and results, see the paper (Achab et al., 2011) entitled Massively multiplayer online role-playing games: comparing characteristics of addict vs non-addict online recruited gamers in a French adult population in Appendix 1.

1.2 Gambling disorder (GD)

A specific feature to GD is gambler’s fallacy and other cognitive biases applied to random conditions related to money incentives. The DSM-5 included chasing money to compensate for losses as a specific criterion in the addictive disorder spectrum to diagnose GD.

,Studies in recent decades on reward and decision making have provided evidence in favor of reward system dysfunction (Clark, 2014). Nevertheless, probably because of methodological limitations, data are contradictory about the nature of this malfunctioning. Some results support the reward deficiency hypothesis of disordered gamblers, whereas others support the reward sensitization of disordered gamblers (Clark, 2014). Recent functional and behavioral data showed an imbalance between different kinds of rewarding conditions in GD, with money becoming an even higher reinforcer than natural rewards (i.e., stronger anticipation and response to monetary outcomes than to erotic cues) (Sescousse, Barbalat, Domenech, &

Dreher, 2013). This imbalance has to be taken into account while designing neuro-functional studies on the reward system.

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20 We could hypothesize that a core addictive symptom (i.e., neglecting other activities, including those that are very meaningful, in favor of the addictive behavior) could somehow have been explained by the competition in reward potency between different rewarding conditions.

The published paper (Achab, Karila, & Khazaal, 2014) reviews neuro-functional data on reward pathway involvement in clinical samples of gamblers with GD. See the paper entitled Pathological gambling: update on decision making and neuro-functional studies in clinical samples in Appendix 2.

2. Assessment features

In our continued investigation into the clinical implications of the features of BAs within addictive disorders, we were interested in obstacles against treatment seeking and early interventions in GD and IGD. We present herein two studies that we conducted to explore the hypothesis of comprehension (e.g., insufficient knowledge about or underestimation of the existence and harms from care professionals, as well as lack of easy-to-use and valid assessment instruments).

2.1. Challenges in the early identification of GD

The recognition of GD in key reference classifications (DSM and the International Classification of Diseases [ICD]) for the last three decades (although it was first categorized under impulse control disorders) seems to have settled the debate on its reality, definition, scientific data comparativeness, magnitude, and evolution. Its recent admission to another category (i.e., Substance-Related and Addictive Disorders in the DSM-5) apparently (after reviewing the titles of published papers in PubMed since the release of the DSM-5) did not have a notable clinical impact (e.g., treatment approaches) nor an effect on research or public health habits (e.g., treatment facilities and prevention strategies). This can be explained by the

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21 fact that, among clinicians, there was already a common language regarding GD and a consistency from one specialist to another in terms of diagnosis and treatment.

Nevertheless, although official criteria are available for the first accepted BA (i.e., GD), only a minor proportion (less than 3%) of patients are in treatment (Evans & Delfabbro, 2005). The major motivators for seeking treatment were reported to be important financial and interpersonal harms resulting from GD (Suurvali, Hodgins, & Cunningham, 2010).

Barriers to seeking help were mainly inner to the patient (e.g., shame and conviction in one’s own capacity to handle the disorder) (Suurvali, Cordingley, Hodgins, & Cunningham, 2009).

Screening thus has great importance and primary care practitioners could be key persons in early detection and referral to specialized care services.

The present paper (Achab, Chatton, et al., 2014) investigated the representations of primary care practitioners about GD and their skills as part of the screening and early intervention process. See the paper entitled Early detection of pathological gambling: betting on GPs' beliefs and attitudes in Appendix 3.

2.2. The Internet as a vector of gambling and gaming disorders and a vector for their assessment

There are consensual screening tools for SUDs, such as the recommended and validated tool of the World Health Organization (WHO) (Khan et al., 2011) to promote early detection and intervention in order to control the harmful effects of drug abuse. For BAs, we are still far from having such consensual tools.

One of the main areas of debate within the scientific community in the field of addiction is the role of the Internet as a new vector for preexisting BAs (e.g., GD) or for new BAs (e.g., IGD) (Achab, et al., 2015). Such ambiguity has an impact on the assessment of BAs.

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22 One assessment strategy could be to use the same screening and diagnosis tools for BAs regardless of their mode of expression (i.e., offline or online). Nevertheless, recent data suggest important differences between online GD and land-based GD in terms of gambling content, prevalence, severity, health consequences, and treatment seeking (Gainsbury, 2015).

The other assessment strategy could be to use specific screening and diagnosis tools for BAs that are mediated in their clinical expression by the Internet. This last assessment option could be undertaken in two ways: (a) the first is to develop specific screening tools for each type of problematic Internet use (i.e., a scale to screen for IGD and another to screen for online GD); and (b) the second is to use the same screening tool for both types of problematic online activities (gaming and gambling).

We tested this last assessment option through a comparative study of Internet-based screening procedures for online gamblers and online gamers using the same assessment tool, the Internet Addiction Test, adapted to each activity. See the paper entitled Factor structure of the Internet Addiction Test in online gamers and poker players (Khazaal et al., 2015) in Appendix 4.

3. Treatment features

The culmination of understanding the psychological features of BAs and of exploring avenues that could enhance diagnosis and help seeking is the treatment response that could be offered to subjects with GD and IGD.

BAs (i.e., GD and IGD) have benefited from psychotherapeutic approaches, mainly those used for SUDs (motivational psychotherapy, brief interventions, and cognitive behavioral therapy [CBT] that showed positive results for IGD and GD) (Achab, et al., 2015; Banz, Yip, Yau, & Potenza, 2016).

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23 Besides these nonspecific treatments, specific approaches to BAs (i.e., cognitive therapy for gambler’s fallacy and financial problem management for GD; specific CBT for family members of those with IGD) have been developed and are now considered to be efficient treatment options (Achab, et al., 2015; Banz, et al., 2016).

A pharmacological treatment response is well demonstrated in SUDs for many indications (e.g., detoxification, relapse prevention, and harm reduction). For non-SUDs, pharmacotherapy used for SUDs has been tested in some trials for GD and IGD and their comorbid psychiatric disorders (Achab, Bertolini, & Karila, 2012; Achab, Khazaal, & Zullino, 2012).

For pharmacological features of GD treatment, see the paper entitled Psychopharmacological treatment in pathological gambling: a critical review (Achab &

Khazaal, 2011) in Appendix 5.

II. Conclusions and perspectives

1. General conclusions

BAs are emerging mental disorders (within the addictive spectrum) and public health issues that constitute great challenges for scientists, clinicians, policy makers, and health managers. Challenges occur at different levels: conceptualization and recognition^a (i.e., the need to define them as mental disorders, to find accurate taxonomy, and to draw the boundaries between them and “normal” behaviors); vulnerability factor identification^b; detection and diagnosis^c; care response^d (i.e., applying efficient therapeutic approaches to those who are suffering as a result of their symptoms and who experience consequences in important areas of their lives); and prevention and health care systems^e (i.e., identifying and

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24 protecting vulnerable subgroups from harmful engagement and designing adequate care facilities).

These challenges are unequally shared by the different BAs (i.e., GD and IGD). GD is scientifically better understood and has benefitted from epidemiological research and public health support, but much effort and data are needed regarding specific vulnerable subgroups (e.g., youth and elderly), health care management, and the understanding and regulation of new gambling offers (e.g., online gambling and gambling through video games). Because they are newer and heterogeneous, Internet-related disorders (i.e., video gaming, social networking, pornography consumption, and shopping) are still in progress in the five previously revealed challenges of facing new health disorders.

GD and IGD are as prevalent as other mental disorders such as opioid and cannabis dependence (Suchtmonitoring, 2014), with young people being more affected. The high rates of associated addictive and other mental disorders constitute additional harm that makes them growing public health concerns.

In the present work, we presented conceptual changes in the addictive spectrum with the recent admission of GD to the DSM-5 as part of Substance-Related and Addictive Disorders and the potential further admission of IGD. We compared SUD, GD, and IGD criteria from the DSM-5 and discussed how specific these criteria were for each of the three addictive disorders under consideration.

2. Findings and future steps

The five published papers that we have presented here contribute to a better understanding of the features of GD and IGD within the addictive spectrum in psychopathology, as well as assessment and treatment that could help enhance consideration of these disorders and improve support for affected individuals. These two goals are the common thread of our

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25 research and clinical and public health activities. We present some ongoing projects in line with this below after we summarize our principal findings.

2.1 Gambling disorder (GD)

The review papers on GD summarize and discuss recent findings on brain correlates of cognitive biases, control inhibition and motivational processes (Achab, Karila, et al., 2014)), and pharmacological trials in clinical samples (Achab & Khazaal, 2011). These reviews provide researchers and clinicians with recent elucidations about the neurocognitive and emotional mechanisms of GD, as well as the effective and promising drugs that could be helpful for future research and for clinical purposes. Indeed, understanding the development and evolution of GD from a neural, environmental, behavioral, and psychological perspective could have therapeutic applications in the treatment of patients with this disorder, in consideration of the interconnection between biology, psyche, and behavior. Moreover, the interactive relationship between clinical practice and research is vital to bring light to the phenomenological understanding of GD.

Beyond phenomenological understanding and the availability of relevant treatment options, an important area of concern is the weak proportion of treatment seekers within problem gamblers despite the physical, mental, and social harms, as we previously discussed.

We explored the hypothesis that primary care professionals could be unaware of the reality of GD, the related health risks and screening tools, or the specialized care system to which potential screened patients can be referred.

GD has consensual, simple-to-use screening tools. Nevertheless, the study that we conducted (Achab, Chatton, et al., 2014) primary care professionals’ self-perception about their knowledge of GD and their reported fluency in screening for it among their patients highlighted the need for training and information to enhance screening practices. These

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26 pivotal professionals in the care system reported being interested in such information and training. We ended the survey with a rapid (two-item) screening tool as an example that they could easily integrate in their care setting, which could be a good starting point to reduce disordered gamblers’ delays in seeking treatment, which could avoid the detrimental psychological, financial, and social consequences of GD.

The social cost of GD in Switzerland, for example, has been estimated to be between 551 and 648 million CHF (Jeanrenaud, Gay, Kohler, Besson, & Simon, 2012). A public health framework would have two main goals: (a) harm reduction through prevention strategies and regulation policies and (b) care through specifically designed help, counseling, and treatment facilities. To these ends, key factors to be considered regarding BAs from a public health perspective are the interconnected compositional and contextual determinants (Marshall, 2009). The compositional determinants consist of characteristics (e.g., socio-demographic and economic) of the subjects living in a determined geographic area associated with problem gambling (e.g., unemployment, social isolation, low socioeconomic groups, youth, mental disorders in immediate relatives) (Marshall, 2009), whereas the contextual determinants are related to characteristics of the local, regional, and national environment, where the individual experiencing gambling problems lives (e.g., type of gambling offer, type of gambling regulation, type of preventive measures against problem gambling, alternative available leisure activities) (Marshall, 2009). We recently published an inventory paper presenting the needs and perspectives of the public health issues of GD in Switzerland (Billieux et al., 2016).

2.2 Internet Gaming Disorder (IGD)

Running an online study with in-game recruitment of adult online gamers was an innovative research design that illustrated the methodological features of Internet-related disorders. We were able to collect interesting data on a representative sample of online gamers, avoiding the usual age and recruitment biases that are present in the literature. Our

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27 study provided descriptive psychological (e.g., impact of gaming on social functioning, health, and emotional states) and socio-demographic data covering the whole range of gamer profiles from casual (i.e., gaming for a few hours weekly for fun) to highly problematic (i.e., gaming as the sole activity with major adverse consequences in their lives).,Internet addiction has been shown to be distinct from IGD, in favor of the working hypothesis that Internet addiction is an umbrella construct comprising heterogeneous disorders (e.g., IGD, online GD, cyber porn addiction). Subjects presenting with IGD showed good consistency between self- perception of problematic gaming engagement and IGD scores, establishing a difference between IGD and SUDs in terms of the concept of denial.

Withdrawal and tolerance symptoms in gaming activity were self-reported, which favors IGD belonging to the addictive spectrum and the presence of dependence symptoms even without substance intake.

The lack of a gold standard to identify is an issue for researchers when studying vulnerability factors and characteristics of disordered subjects, as we previously discussed. It is also an issue for practitioners who have to decide who to treat or not in treatment-seeking patients. Furthermore, this is problematic for prevention and early detection, even though many attempts have been made to develop and validate screening tools (Achab, Meuli, et al., 2014; Khazaal, et al., 2015; Khazaal et al., 2008; Khazaal et al., 2012)

The adaptation of substance dependence criteria to online gaming activity in the first published paper that we presented (Achab, et al., 2011) has shown good psychometric properties for identifying IGD. This could be a screening tool that is easy to remember (identical to SUD assessment criteria) and to use (7 items only) for non-specialists.

We also tested the factorial structure of the Internet Addiction Test adapted for IGD and online GD in the fourth paper (Khazaal, et al., 2015) in the present work. It proposed a data-

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28 driven shorter version of a widely used questionnaire, addressing some of its psychometric limitations.

For further knowledge of an individual’s determinants to develop problematic (excessive or addictive) patterns of Internet and electronic device use, data from the clinical population, face-to-face interview settings, and objective measurements (e.g., using tasks) are crucial yet still scarce. We are currently developing a cohort study project on outpatients seeking treatment for Internet-related complaints (e.g., gaming, social networking, pornography viewing, and gambling). The aims of this study are organized around several key challenges in the field, as mentioned earlier in the conclusion.

Patients will be diagnosed by using structured interviewing, which will be compared with self-administered questionnaires and with subjective problem rating by a key relative.

Structured interviews and experimental tasks are planned to collect data on factors related to the patient (e.g., socio-demographic, perceived quality of life, motivations to engage in the problematic activity and benefits sought in it, depression, anxiety disorders, impulsivity, self- esteem, coping strategies, and attachment patterns) and factors related to the patient’s environment (e.g., family history of mental and addictive disorders, accessibility of the problematic activity, and availability of alternative leisure activities). These data will be correlated to problematic use dimensions to explore risk factors. Protective factors from problematic use of other online activities will also be investigated.

The cohort project will provide useful data on the motivators to seek help, as well as on referral modalities, the efficacy of treatment approaches (e.g., evolution of problematic behaviors, clinical impression of the psychotherapist, quality-of-life improvement, satisfaction of relatives), follow-up characteristics (e.g., dropouts, duration, remissions, and relapses), and recovery factors.

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29 Besides psychotherapeutic and pharmacological approaches, we want to develop new treatment approaches to alleviate patients’ suffering. The use of noninvasive brain stimulation has shown efficacy in SUDs (Trojak et al., 2015; Trojak et al., Under review) and in some BAs (e.g., eating disorders) (Sauvaget et al., 2015). They could represent interesting therapeutic tools to be tested in IGD (Trojak, Zullino, & Achab, 2015). We are currently drafting a multicentric protocol between Switzerland and France on the efficacy of transcranial direct-current stimulation in IGD. The expected treatment outcomes include craving reduction as observed for SUDs, control recovery of online involvement, and reduction of risk taking and impulsivity as assessed by experimental tasks.

3. Global perspectives

BAs (e.g., GD and IGD), beyond their recognition, screening, and treatment at an individual, micro (e.g., family), and meso level (e.g., community), require interest and effort at two additional levels (i.e., macro and global).

3.1 Macro level

At a national level, several countries have developed and supported national and international programs for GD (e.g., Gambling Commission in the United Kingdom, National Council on Problem Gambling strategic plan in the United States, and European Commission recommendations on gambling). The recently adopted Swiss national strategy on addictive disorders includes BAs. This recognition as a national public health issue will offer interesting perspectives of action and support after its implementation next year. In Switzerland, epidemiological and contextual data are needed on BAs to monitor their prevalence and distribution in the general population and in specific subgroups (Billieux, et al., 2016; Richter

& Walker, 2016). These data are still lacking, for example, regarding Internet-related disorders in elderly persons, as we found in a recently published review on Internet-related disorders (M’hiri et al., 2015).

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30 Knowledge on treatment coverage and care needs is also crucial for allocating adequate resources to reduce related harms. Moreover, the national gambling regulation law is being revised in consideration of the challenging issue of gamblers’ protection. An online offer is a particularly harmful setting that needs to be addressed through specific regulation strategies (Khazaal et al., 2011). We are working to bring these points to federal and regional boards.

3.2 Global level

There is a need to address these health issues in an optimum way by dealing with remaining challenges such as promoting global research and cooperation. An ethical committee recently approved an exploratory study protocol that we submitted to provide data on Internet-related disorders (gaming, gambling, and social networking) in older adults with a cross-cultural (Switzerland and Poland) comparative design.

Regarding the global monitoring of GD and IGD, we are involved, through our WHO collaborating center activities, in the data collection of addictive disorders in health systems at a global level. This monitoring is part of the Mental Health Action Plan 2013-2020 in which the objectives include the promotion and implementation of prevention strategies on the one hand, and the strengthening of evidence and research on the other (Saxena, Funk, &

Chisholm, 2013).

The development of cross-cultural public health guidelines and their implementation in any type of linguistic, politic, economic, or local priority setting is the culmination of the previous medical, scientific, and public health efforts. We expect from our work in progress with WHO (WHO, 2015), to achieve some of these important goals.

An outcome that is highly anticipated by clinicians and researchers is the release of the 11th edition of the ICD (ICD-11) scheduled in 2018. The release of the ICD-11 presents an opportunity to verify whether WHO aligns with the DSM-5 regarding the widening of the

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31 addictive disorder spectrum to include so-called BAs. The loop will finally be closed with this categorization update, from the individual complaint to global clinical guidelines, which will then have an impact on diagnosis and research at the individual level.

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Features of Gambling Disorder and Internet Gaming Disorder in the spectrum of addictive disorders

Thesis

Reference

Features of Gambling Disorder and Internet Gaming Disorder in the spectrum of addictive disorders

Features of Gambling disorder and Internet gaming disorder in the spectrum of addictive

disorders

Table of contents

Summary

I. Introduction

II. Conclusions and perspectives

References