Problem Gambling Severity Index Scores Research Articles

Gambling and military Service: Characteristics, comorbidity, and problem severity in an epidemiological sample

Active military members and veterans both show elevated risk of Gambling Disorder. However, research comparing these groups to civilians in epidemiological samples is sparse. There is also some research suggesting that there is a stronger association between military service and poor mental outcomes for women.The current study applies bivariate analyses and generalized linear modelling predicting Problem Gambling Severity Index scores to a representative, complex survey sample of 2176 New Jersey adult residents.The results show that problem gambling scores for past and current military service members were more than double that of the civilian participants after controlling for relevant demographic and behavioral characteristics. Additionally, the relationship between problem gambling scores and military service was significantly stronger for women than men. Bivariate analyses indicated that active military service members scored higher on the Problem Gambling Severity Index, indicated greater weekly participation in online gambling, lottery, electronic gambling machine, and sports betting, and nearly 20 times the rate of suicidal ideation compared with civilians. Additional regression analysis show that among military service members problem gambling scores were associated with suicidal ideation, tobacco use, and substance use problems.The results are discussed in the context of a period of expansion of online gambling opportunities. Constrained options for leisure coupled with the high propensity for risk taking among military service members and the relative ease of concealing online gambling on base may expose military service members to disproportionately higher risk of Gambling Disorder.

Online Survey of Gambling Participation and Problem Gambling in Chiba City: Problem Gambling Rates May be Strongly Influenced by the Administration Mode.

Prevalence studies on gambling participation and problem gambling in Japan have been limited. To obtain data showing the current status of gambling in Japan, we conducted an online survey on gambling participation and problem gambling among residents in Chiba City. The online data collection was conducted through an Internet research firm. Questionnaires were consisted of personal demographics, past-year gambling participation and severity of gambling risks. The Problem Gambling Severity Index (PGSI) was used as a survey instrument. Males (51.5%) were significantly more likely than females (25.5%) to have gambled in the past year. Problem gamblers (PGSI score ≧ 8) were 7.2% among males and 1.2% among females. Problem gambling was strongly correlated with frequent gambling, preference for Pachinko/Slot and smoking habit. The gambling participation rates were roughly lower than those reported in many overseas jurisdictions, whereas the problem gambling rates were considerably higher than those reported in the same jurisdictions. According to the total consumption model, it would be reasonable to consider that gambling participation rates show a positive correlation with problem gambling rates. The high levels of problem gambling may be due to the administration mode using online sampling, by which answers admitting unapprovable behaviors like problem gambling tend to increase. This suggests that the previous studies using conventional face-to-face or telephone methods may have underestimated problem gambling rates.

Psychometric Validation of the Persian Version of the Problem Gambling Severity Index

The Problem Gambling Severity Index (PGSI) has been the most frequently used instrument for prevalence studies for problem gambling in recent years. To date, there have been very few gambling studies among Persian populations. The objective of the present study was to investigate the reliability and validity of the Persian version of the PGSI. The original version of the PGSI was translated and back-translated into Persian, followed by a pilot study. A sample of Iranian online gamblers (n = 858) was recruited utilizing social media platforms. Results showed that the Persian PGSI had excellent internal consistency (Cronbach’s alpha coefficient = 0.90; composite reliability = 0.91) and moderate test-retest reliability after 4–6 weeks using intraclass coefficient (0.41 with 95% CI [.34, .49]). The maximum likelihood confirmatory factor analysis for one-factor PGSI model fitted well (χ2/df = 2.81, CFI = .974, SRMR = .028, PCLOSE > .05, RMSEA = .057, 90% CI [.037, .077]). As for criterion-related validity, the Persian PGSI score correlated with the score on the Hospital Anxiety Depression Scale, which assesses depression (r = .54, p < .01) and anxiety (r = .40, p < .01). The Persian PGSI is a reliable and valid instrument for assessing the prevalence of problem gambling among Persian populations.

Positive play and its relationship with gambling harms and benefits.

BackgroundEngagement in responsible or ‘positive play’ strategies is known to be negatively associated with problem gambling, as indexed by measures such as the Problem Gambling Severity Index (PGSI). Less is known about whether positive play is associated with reduced harm or a greater ability to enjoy the recreational benefits of gambling.AimsThis study investigated the relationship between positive play and gambling harm after controlling for PGSI scores and whether positive play moderated the relationship between PGSI scores and harm. It also examined whether positive play was related to perceived benefits associated with gambling.MethodsThe study utilised an online panel sample of 554 respondents who completed a survey that included the PGSI, measures of gambling harm drawn from Browne et al. (2016), and the newly developed Positive Play Scale (Wood et al., 2019). The study involved predominantly monthly gamblers with higher levels of gambling risk: 23% problem gamblers; 36% moderate risk; and 21% low risk gamblers.ResultsThe results indicated that positive play was negatively associated with reduced gambling harm. The behavioural Positive Play subscales relating to pre-commitment and honesty and control explained additional variation in harm after controlling for PGSI scores. Higher levels of positive play also moderated and reduced the relationship between the PGSI and gambling harm. Perceived benefits were, unexpectedly, found to be higher in problem gamblers and negatively related to positive play.ConclusionBehavioural measures of positive play appear to be useful moderating factors in understanding the relationship between problem gambling and harm. Higher-risk gamblers appear to experience both greater costs as well as benefits from gambling, which likely reflects a stronger personal need to engage in the activity.

Impulsive Sports Betting: The Effects of Food or Substance Consumption.

The present study aimed to explore how food or substance consumption (e.g., experiencing hunger, or having consumed alcohol or recreational drugs) could shape consumer impulsive spending on sports betting products. Based on a large online sample of Australian sports bettors, we found that participants with higher hunger level, or having consumed more alcohol or recreational drugs, tended to have increased impulsive bet size. These impulsiveness effects had both direct and indirect effect components. The significant direct effects confirmed that positive relationships directly existed between hunger, alcohol consumption, or recreational drug consumption and impulsive bet size, even when all potential mediators and covariates were statistically controlled. Moreover, results regarding specific indirect effects demonstrated that hunger, alcohol consumption, or recreational drug consumption was also indirectly linked with impulsive bet size, via their relationships with both promotional and financial influences, rather than social influences. Furthermore, participants' Problem Gambling Severity Index score was positively associated with their impulsive bet size. These findings support and complement the literature on impulsivity as well as the research on strategies for staying in control of gambling, and have implications for consumers, regulators, and treatment/help providers.

Development and validation of the Japanese version of the problem gambling severity index

BackgroundThe Problem Gambling Severity Index (PGSI) has been the most frequently used instrument for prevalence studies of problem gambling in the 2010s. However, the Japanese version of the PGSI has yet to be developed. ObjectiveTo develop the Japanese version of the PGSI and to investigate its reliability and validity. Materials and methodsWe translated and back-translated the original version of the PGSI into Japanese. The author of the original PGSI confirmed the semantic equivalence between the original PGSI and its Japanese version. We examined the reliability and validity of the Japanese version of the PGSI using data from a nationwide prevalence study of problem gambling conducted in Japan in 2017. ResultsUsable responses were obtained from 5365 residents. The PGSI had excellent internal consistency (Cronbach's alpha coefficient: 0.89) and moderate test-retest reliability after 45–60 days (intraclass coefficient: 0.54). Exploratory factor analysis revealed the unidimensionality of the PGSI. As for criterion validity, using the diagnosis of gambling disorder in DSM-5 as a reference standard, the stratum specific likelihood ratios of the PGSI score of 0 = non-problem; 1–2 = low risk; 3–7 = moderate risk; and 8–27 = problem gambling were 0.00; 0.68 (95% confidence interval: 0.21 to 2.22); 8.71 (5.2 to 14.5); and 67.9 (35.6 to 129.5) respectively. ConclusionsWe recommend including the PGSI in future prevalence studies of problem gambling in Japan.

Predictors of gambling and problem gambling in Victoria, Australia

In 2016, the gambling habits of a sample of 3361 adults in the state of Victoria, Australia, were surveyed. It was found that a number of factors that were highly correlated with self-reported gambling frequency and gambling problems were not significant predictors of gambling frequency and problem gambling. The major predictors of gambling frequency were the degree to which family members and peers were perceived to gamble, self-reported approval of gambling, the frequency of discussing gambling offline, and the participant’s Canadian Problem Gambling Severity Index (PGSI) score. Age was a significant predictor of gambling frequency for certain types of gambling (e.g. buying lottery tickets). Approximately 91% of the explainable variance in the participant’s PGSI score could be explained by just five predictors: Positive Urgency; Frequency of playing poker machines at pubs, hotels or sporting clubs; Participation in online discussions of betting on gaming tables at casinos; Frequency of gambling on the internet, and Overestimating the chances of winning. Based on these findings, suggestions are made as to how gambling-related harm can be reduced.

Gambling Problem Trajectories and Associated Individuals Risk Factors: A Three-Year Follow-Up Study Among Poker Players.

Despite the popularity in poker-related activities in recent years, few studies have focused on the evolution of gambling habits of poker players over a long period of time. The aim of this study is to examine factors influencing trajectories of poker players. The results are based on data collected at a four-time measurement of a prospective cohort study conducted in Quebec (n = 304 poker players). A latent class growth analysis was performed to identify trajectories based on the Problem Gambling Severity Index score. Multinomial multivariable logistic regression analyses were conducted to determine the correlates of gambling trajectories. Over the 3 years of the study, three gambling problem trajectories were identified, comprising one decreasing trajectory (1st: non-problematic-diminishing), one stable trajectory (2nd: low risk-stable), and one increasing trajectory (3th: problem gamblers-increasing). Internet as the main poker form and number of game played were associated with at-risk trajectories. Depression symptoms were significant predictors of the third trajectory whereas impulsivity predicted the second trajectory. This study shows that the risk is remaining low over years for the vast majority of poker players. However, the vulnerable poker players at the beginning of the study remain on a problematic increasing trajectory. It is therefore important to prioritize individuals in the third trajectory for interventions.

Exploring relationships between problem gambling, scratch card gambling, and individual differences in thinking style

Background and aimsScratch cards are a popular form of lottery gambling available in many jurisdictions. However, there is a paucity of research that examines associations between individual differences in thinking style, participation in scratch card gambling, and problem gambling severity.MethodsIn three studies, we sought to examine the relationships among these variables in large, online samples of participants. Participants completed the Cognitive Reflection Test (CRT), the Problem Gambling Severity Index (PGSI), the Actively Open-Minded Thinking Scale, and self-reported their frequency of scratch card gambling.ResultsThroughout all three studies, specific associations were reliably established. Specifically, negative associations were observed between participants’ CRT and PGSI scores, as well as between participants’ CRT scores and scratch card gambling frequency. In addition, we found a positive association between problem gambling severity and scratch card gambling frequency. Finally, problem gambling severity was shown to correlate positively with participants’ willingness to pay for irrelevant information in a scratch card gambling scenario.Discussion and conclusionsOverall, we observed that problem gambling severity is associated with an individuals’ thinking style and scratch card gambling behavior. This study adds to the existing literature examining problem gambling, and highlights the role of thinking style in understanding gambling behavior and problematic gambling.

A latent class analysis of young adult gamblers from the Manitoba Longitudinal Survey of Young Adults

ABSTRACTInformed by the Pathways Model, the current study utilized latent class analysis (LCA) to empirically derive subtypes of gamblers based on measures of impulsivity, anxiety, depression, drug use and alcohol dependence. The sample in this study (N = 566) was comprised of young adult gamblers (18–22 years of age) who participated in the Manitoba Longitudinal Survey of Young Adults (MLSYA). Multinomial regression was utilized to examine how demographic variables and participant scores on the Problem Gambling Severity Index (PGSI) predicted membership in gambler classes from the LCA. Results of the LCA revealed three classes of gamblers: emotionally vulnerable, non-problem and impulsive. Multinomial regression showed that older age (i.e. 20–22 years of age), lower income (< $20,000 per year), living independently and PGSI scores were associated with increased odds of being classified as an impulsive gambler. Identifying as European, living independently and PGSI scores were associated with increased odds of being grouped in the emotionally vulnerable class of gambler. These results suggest that young adult gamblers are not a homogeneous group but instead are best understood as falling into different subtypes based on shared characteristics outlined in the Pathways Model.

Differential Effects of Formal and Informal Gambling on Symptoms of Problem Gambling During Voluntary Self-Exclusion.

Voluntary self-exclusion (VSE) programs enable problem gamblers to engage in a break from casino-based gambling. The current study analyzed the effects of a VSE program in British Columbia, Canada on problem gambling symptoms and the comparative reductions in problem gambling symptoms when participants abstained from gambling, continued to participate in non-casino based gambling, or attempted to violate their exclusion contract. 269 participants completed two telephone interviews over a 6-month period. Participants were administered the Problem Gambling Severity Index (PGSI). Substantial reductions in PGSI scores were observed after 6months. Program violators had significantly smaller PGSI Difference Scores by Time 2 compared to those who continued to gamble outside of the casino and those who completely abstained from all gambling. There were no significant differences between those who gambled informally and those who abstained. A multiple regression identified that while access to counselling and length of enrollment also contributed to the reduction in PGSI scores, violation attempts were most strongly associated with smaller reductions in symptoms of problem gambling. These results imply that some gamblers can successfully engage in non-casino based forms of gambling and still experience reductions in symptoms of problem gambling. Future analyses will explore characteristics associated with group membership that may help to identify which participants can successfully engage in non-casino based gambling without re-triggering symptoms of problem gambling.

Dark Flow, Depression and Multiline Slot Machine Play

Multiline slot machines allow for a unique outcome type referred to as a loss disguised as a win (LDW). An LDW occurs when a player gains credits on a spin, but fewer credits than their original wager (e.g. 15-cent gain on a 20-cent wager). These outcomes alter the gambler’s play experience by providing frequent, albeit smaller, credit gains throughout a playing session that are in fact net losses. Despite this negative overall value, research has shown that players physiologically respond to LDWs as if they are wins, not losses. These outcomes also create a “smoother” experience for the player that seems to promote a highly absorbing, flow-like state that we have called “dark flow”. Past research has indicated that there may be a relationship between problem gambling status and dark flow, as well as between dark flow, depression, and gambling expectancies. In this study, we sought to further understand these relationships, while examining the influence of LDWs on game preference in the context of single versus multiline slots play. We used a realistic slot machine simulator equipped with a force transducer to measure how hard players pressed the spin button following different outcomes. This measure of arousal showed that LDWs were treated similarly to small wins. Participants overwhelmingly preferred the multiline game and experienced more positive affect while playing it, compared to the single-line game. Problem gambling severity index scores were related to dark flow in both games, but this relationship was stronger for the multiline game. Additionally, depression symptomatology and dark flow were strongly correlated in the multiline game, with significant relationships between depression and gambling expectancy, and gambling expectancy and dark flow ratings also emerging.

Gambling behavior among Macau college and university students

This survey investigated gambling behavior among Chinese students studying in Macau colleges and universities. It also aimed to examine the relationship between problem gambling, affect states and sensation seeking propensity. A convenience sample of 999 students (370 men, 629 women) filled a self-administered questionnaire consisted of the Problem Gambling Severity Index (PGSI) (Ferris and Wynne in The Canadian problem gambling index: User manual. Canadian Centre on Substance Abuse, Toronto 2001a), the 8-item Brief Sensation Seeking Scale (BSSS-8) (Hoyle et al. Pers Individ Diff 32(3): 401–414, 2002), Bradburn’s Affect Balance Scale (BABS) (Bradburn in The structure of psychological well-being. Aldine, Chicago 1969) and questions on gambling activities. The response rate is 65%. Results indicate 32.3% (n = 323) of the survey participants wagered on mahjong (61.8%), soccer matches (40.2%), Mark Six lottery (37.2%), card games (28.1%), land-based casino gambling (13.1%), slot machines (7.5%) and online casino games (2.0%). The average monthly stake was MOP $411. Seeking entertainment (18.7%), killing time (12.5%) and peer influence (11.1%) were the three main reasons for gambling. Using the PGSI, 3.6 and 5.3% of the students could be identified as moderate-risk and problem gamblers respectively. Men were significantly more vulnerable to gambling problems (X2(1) = 35.00, p < 0.01) than women. Most of the problematic gamblers (76%) made their first bet before 14 years. The PGSI scores are significantly correlated with the BSSS-8 scores (r = 0.23, p < 0.01) but not with the overall ABS scores (r = −0.06, p > 0.05). The study findings inform campus prevention programs and future research.

Cue-Reactive Rationality, Visual Imagery and Volitional Control Predict Cue-Reactive Urge to Gamble in Poker-Machine Gamblers

Poker-machine gamblers have been demonstrated to report increases in the urge to gamble following exposure to salient gambling cues. However, the processes which contribute to this urge to gamble remain to be understood. The present study aimed to investigate whether changes in the conscious experience of visual imagery, rationality and volitional control (over one's thoughts, images and attention) predicted changes in the urge to gamble following exposure to a gambling cue. Thirty-one regular poker-machine gamblers who reported at least low levels of problem gambling on the Problem Gambling Severity Index (PGSI), were recruited to complete an online cue-reactivity experiment. Participants completed the PGSI, the visual imagery, rationality and volitional control subscales of the Phenomenology of Consciousness Inventory (PCI), and a visual analogue scale (VAS) assessing urge to gamble. Participants completed the PCI subscales and VAS at baseline, following a neutral video cue and following a gambling video cue. Urge to gamble was found to significantly increase from neutral cue to gambling cue (while controlling for baseline urge) and this increase was predicted by PGSI score. After accounting for the effects of problem-gambling severity, cue-reactive visual imagery, rationality and volitional control significantly improved the prediction of cue-reactive urge to gamble. The small sample size and limited participant characteristic data restricts the generalizability of the findings. Nevertheless, this is the first study to demonstrate that changes in the subjective experience of visual imagery, volitional control and rationality predict changes in the urge to gamble from neutral to gambling cue. The results suggest that visual imagery, rationality and volitional control may play an important role in the experience of the urge to gamble in poker-machine gamblers.

Types of gambling and levels of harm: A UK study to assess severity of presentation in a treatment-seeking population.

Background and aimPrevious international research emphasized that some forms of gambling are more “addictive” than others. More recently, research has shown that we should shift our attention from the type of gambling activity to the level of involvement in a number of different gambling activities. The aim of our study was to verify whether a higher Problem Gambling Severity Index (PGSI) score was associated with particular gambling activities and evaluate the impact of involvement on gambling behavior.MethodsA total of 736 treatment-seeking individuals with gambling disorder were assessed at the National Problem Gambling Clinic in London. First, the independent two-sample t-test and the Mann–Whitney test were used to verify if the PGSI score changed significantly according to the gambling activity at a bivariate level. Second, we conducted a cluster analysis and finally, we fitted a linear regression model in order to verify if some variables are useful to predict gambling addiction severity.ResultsThe PGSI score was significantly higher for lower stakes gaming machine gamblers (1% significance level) and for fixed-odds betting terminal (FOBT) gamblers (5% significance level) at a bivariate level. Moreover, such finding was confirmed by cluster and linear regression analyses.ConclusionsThe results of this study indicated that gambling addiction severity was related to gambling involvement and, for a given level of gambling involvement, gambling addiction severity may vary according to gambling type, with a particularly significant increase for FOBT and gaming machine gambling.

Pathways and transitions of gamblers over two years

Moderate-risk and problem gamblers represent 1.4% and 0.4% of the Québec population, respectively. Research on gamblers’ trajectories has been hampered by methodological shortcomings leading to heterogeneous results. The present research was conducted in the Province of Québec with a representative sample of adult gamblers and aims to explore how gamblers change over time according to the severity of their gambling problems. Using a 2-year follow-up prospective design (3 waves), 179 gamblers selected from a representative survey were divided into the 4 PGSI (Problem Gambling Severity Index) categories. Beyond the decreasing trend in PGSI scores detected within the overall sample using a linear growth model, our analyses revealed that moderate-risk gamblers are heterogeneous in their composition and evolution, comprising stable moderate-risk, recent cases and former problem gamblers. Over three waves, one-third of moderate-risk gamblers improved, one-third remained stable and one-third became problem gamblers. The subgroups transitioning in and out of the moderate-risk category differed in terms of reported changes in gambling behaviours and consequences. Problem gamblers remain vulnerable over time, being at risk of experiencing chronic problems. Results highlight the necessity of subgroup-specific prevention programmes and treatment services that address both the non-linearity of risky gambling and the chronicity of problem gambling.

Serum BDNF levels in patients with gambling disorder are associated with the severity of gambling disorder and Iowa Gambling Task indices.

Background and aimsGambling disorder (GD) shares many similarities with substance use disorders (SUDs) in clinical, neurobiological, and neurocognitive features, including decision-making. We evaluated the relationships among, GD, decision-making, and brain-derived neurotrophic factor (BDNF), as measured by serum BDNF levels.MethodsTwenty-one male patients with GD and 21 healthy sex- and age-matched control subjects were evaluated for associations between serum BDNF levels and the Problem Gambling Severity Index (PGSI), as well as between serum BDNF levels and Iowa Gambling Task (IGT) indices.ResultsThe mean serum BDNF levels were significantly increased in patients with GD compared to healthy controls. A significant correlation between serum BDNF levels and PGSI scores was found when controlling for age, depression, and duration of GD. A significant negative correlation was obtained between serum BDNF levels and IGT improvement scores.DiscussionThese findings support the hypothesis that serum BDNF levels constitute a dual biomarker for the neuroendocrine changes and the severity of GD in patients. Serum BDNF level may serve as an indicator of poor decision-making performance and learning processes in GD and help to identify the common physiological underpinnings between GD and SUDs.

Gender, gambling settings and gambling behaviours among undergraduate poker players

A gender divide in gambling is commonly observed among college populations. This study examines whether settings where students gamble on poker mediate the relationship between gender and poker gambling behaviours. Undergraduate poker players, 126 females and 242 males, were randomly sampled from three universities in Montreal, Canada. Three outcomes measuring risky behaviours were considered: severity of gambling problems as measured by the Problem Gambling Severity Index (PGSI), past-year poker spending and past-year poker debt. Multiple mediation analyses were conducted. The effect of gender on outcomes was analysed through three putative mediators: gambling on poker in private residences, in public locations or on the Internet. Male gender positively relates to risky gambling behaviours and occurrence of gambling in various settings. Risky gambling behaviours are positively related to gambling in various settings. Overall, the occurrence of playing poker in public locations and on the Internet emerged as significant mediators in relation to PGSI score, past-year poker spending and past-year poker debt. Given the nature of the processes by which gender is related to risky gambling behaviours among undergraduate students, gambling needs to be understood through a perspective that focuses as much on contexts as it does on individuals.

Subtyping based on readiness and confidence: the identification of help-seeking profiles for gamblers accessing web-based counselling.

Problem gamblers are not a homogeneous group and recent data suggest that subtyping can improve treatment outcomes. This study administered three readiness rulers and aimed to identify subtypes of gamblers accessing a national web-based counselling service based on these rulers. Participants were 1204 gamblers (99.4% problem gamblers) who accessed a single session of web-based counselling in Australia. Measures included three readiness rulers (importance, readiness and confidence to resist an urge to gamble), demographics and the Problem Gambling Severity Index (PGSI). Gamblers reported high importance of change [mean = 9.2, standard deviation (SD) = 1.51] and readiness to change (mean = 8.86, SD = 1.84), but lower confidence to resist an urge to gamble (mean = 3.93, SD = 2.44) compared with importance and readiness. The statistical fit indices of a latent class analysis identified a four-class model. Subtype 1 was characterized by a very high readiness to change and very low confidence to resist an urge to gamble (n = 662, 55.0%) and subtype 2 reported high readiness and low confidence (n = 358, 29.7%). Subtype 3 reported moderate ratings on all three rulers (n = 139, 11.6%) and subtype 4 reported high importance of change but low readiness and confidence (n = 45, 3.7%). A multinomial logistic regression indicated that subtypes differed by gender (P < 0.001), age (P = 0.01), gambling activity (P < 0.05), preferred mode of gambling (P < 0.001) and PGSI score (P < 0.001). Problem gamblers in Australia who seek web-based counselling comprise four distinct subgroups based on self-reported levels of readiness to change, confidence to resist the urge to gamble and importance of change.

SY26-3 * SERUM BDNF LEVELS IN PATIENTS WITH GAMBLING DISORDER ARE ASSOCIATED WITH THE SEVERITY OF GAMBLING DISORDER AND IOWA GAMBLING TASK INDICES

Background. Brain derived neurotrophic factor (BDNF) plays an important role in the pathophysiology and cognitive dysfunction of substance use disorders (SUDs). Gambling disorder (GD) shares many similarities with SUDs in clinical, neurobiological and neurocognitive features, including decision making. Methods. To evaluate the relationship among BDNF, GD and decision making, serum BDNF levels were assessed in 21 male patients with GD and 21 healthy sex- and age-matched control subjects. The severity of GD was measured with the Problem Gambling Severity Index (PGSI). We then investigated the association between serum BDNF levels and the severity of GD. Finally, we analyzed the association between the serum BDNF levels and Iowa Gambling Task (IGT) indices. Results. Mean serum BDNF levels were significantly increased in the patients with GD compared to healthy controls (p < .0001). We also found a significant correlation between serum BDNF levels and PGSI scores (r = .558, p = 0.02) when controlling for age, depression, and duration of GD. In terms of IGT indices, a negative correlation was identified between serum BDNF levels and IGT improvement scores (r = -.477, p < .05). Conclusions. The findings of this study support the hypothesis that serum BDNF levels may constitute a dual biomarker for the neuroendocrinological changes and the severity of GD in patients. Furthermore, serum BDNF level may be an indicator of poor decision-making performance, especially in terms of learning processes implicated in GD. With continued investigation, this line of research could expand our understanding of the common neurobiological underpinnings of SUDs and GD.