Genetic and environmental origins of gambling behaviors from ages 18 to 25: A longitudinal twin family study

What is known about population level programs designed to address gambling-related harm: rapid review of the evidence

BACKGROUND

Gambling and gambling-related harm attract significant researcher and policy attention. The liberalisation of gambling in most western countries is strongly associated with a marked rise in gambling activity and increases in gambling-related harm experienced at the population level. Programs to address gambling-related harm have traditionally focused on individuals who demonstrate problematic gambling behaviour, despite clear evidence of the effectiveness of a public health approach to high-risk activities like gambling. Little is known about the availability or efficacy of programs to address gambling-related harm at a population level.

METHODS

The Victorian Responsible Gambling Foundation commissioned a rapid evidence review of the available evidence on programs designed to reduce gambling-related harm at a population level. The review was conducted using a public health and harm reduction lens. MEDLINE, ProQuest Central and PsychInfo databases were searched systematically. Included studies were published in English between 2017 - 2023 from all countries with gambling policy contexts and public health systems comparable to Australia's; included primary data; and focused on primary and/or secondary prevention of gambling-related harm or problems.

RESULTS

One hundred and sixty-seven articles were eligible for inclusion. Themes identified in the literature included: risk and protective factors; primary prevention; secondary prevention; tertiary prevention; target population group; and public health approach. The evidence review revealed a gap in empirical evidence around effective interventions to reduce gambling-related harm at the population level, particularly from a public health perspective.

CONCLUSIONS

Addressing gambling-related harm requires a nuanced, multi-layered approach that acknowledges the complex social, environmental, and commercial nature of gambling and associated harms. Moreover, evidence demonstrates community programs to reduce gambling-related harm are more successful in reducing harm when based on sound theory of co-design and address the social aspects that contribute to harm.

Genetic Aspects of Problematic and Risky Internet Use in Young Men-Analysis of ANKK1, DRD2 and NTRK3 Gene Polymorphism

BACKGROUND

Internet addiction disorder (IAD) is characterized by an excess of uncontrolled preoccupations, urges, or behaviors related to computer use and Internet access that culminate in negative outcomes or individual distress. PIU includes excessive online activities (such as video gaming, social media use, streaming, pornography viewing, and shopping). The aim of this study was to analyze the association of gene polymorphisms that may influence the severity of risky behaviors in young men with the frequency of Internet use. We speculate that there are individual differences in the mechanisms of Internet addiction and that gene-hormone associations may represent useful biomarkers for subgroups of individuals.

MATERIALS AND METHODS

The study was conducted in a sample of 407 adult males. Subjects were asked to complete the Problematic Internet Use Test (PIUT). Serum was analyzed to determine concentrations of luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone (TT), sex hormone binding protein (SHBG), dehydroepiandrosterone sulfate (DHEA-S), estradiol (E2), prolactin (PRL), insulin (I), serotonin (5-HT), and dopamine (DA), as well as DRD2, ANKK1, and NTRK3 gene polymorphisms.

RESULTS

In the analysis of the ANKK1 gene, there was a specific association between ANKK1 polymorphisms and PRL and 5-HT blood concentrations. There was also an association between the ANKK1 polymorphisms and LH and DA concentrations. When analyzing the DRD2 gene polymorphism, we found that in the group with a moderate level of Internet dependence, there was an association between both the G/GG and GG/GG polymorphisms and FSH concentration.

CONCLUSIONS

Our study found that there may be an association between the NTRK3 gene polymorphism and PIU. The polymorphisms of ANKK1 and DRD2 genes may be factors that influence the concentrations of hormones (PRL, 5-HT, DA) that are associated with the results obtained in PIU.

The genetics of gaming: A longitudinal twin study

Background

Gaming is a popular past-time activity among children and adolescents, but it there is also a possible link to negative consequences such as psychological distress and lowered academic achievement. However, there are fundamental knowledge gaps remaining regarding central characteristics of gaming such as heritability, stability over time, and sex differences. We examined the genetic and environmental contribution to gaming behavior, including sex differences, continuity and change, in a longitudinal cohort of twins.

Methods

This is the first longitudinal twin study on gaming, involving 32,006 twins in Sweden. Parents were asked about the twins' gaming at ages 9, 15 and 18. We used univariate and multivariate twin analyses to estimate the relative contribution of genetic and environmental influences at each time-point as well as across time. Sex-differences were also explored.

Results

The results showed large sex differences, where genetics explained more of the variance for boys (31.3%-62.5% depending on age) than for girls (19.4%-23.4%). Genetic factors explained an increasing amount of the variance for boys (31.3% at age 9, 62.5% at age 15 and 53.9% at age 18). Shared environmental factors explained a larger proportion of the variance among girls, which remained relatively stable over time (70.5% at age 9, 61.8% at age 15 and 60.5% at age 18). The results also indicated that most of the variance came from genetic and environmental sources specific to each age.

Conclusions

Compared to many other behavioral phenotypes, such as gambling, gaming was relatively unstable with a large degree of genetic innovation. There were large sex differences in the contribution of genetic and environmental factors. This suggests that excessive gaming could be the result of age- and sex-specific genetic and environmental factors, and should be taken into account when mapping gaming behaviors, since these behaviors might be under continual etiological transformation.

Predicting disordered gambling across adolescence and young adulthood from polygenic contributions to Big 5 personality traits in a UK birth cohort

BACKGROUND AND AIMS

Previous research has demonstrated phenotypical associations between disordered gambling (DG) and Big 5 personality traits, and a twin study suggested that shared genetic influences accounted for a substantial portion of this relation. The present study examined associations between DG and polygenic scores (PSs) for Big 5 traits to measure the shared genetic underpinnings of Big 5 personality traits and DG.

DESIGN

Zero-inflated negative binomial regression models estimated associations between Big 5 PSs and past-year and life-time assessments of DG in a longitudinally assessed population-based birth cohort.

SETTING

United Kingdom.

PARTICIPANTS

A total of 4729 unrelated children of European ancestry from the Avon Longitudinal Study of Parents and Children (ALSPAC) with both phenotypical and genetic data.

MEASUREMENTS

Phenotypical outcomes included past-year assessment of DG using the problem gambling severity index (PGSI) and life-time assessment of DSM-IV pathological gambling symptoms (DPG) across the ages of 17, 20 and 24 years. Polygenic scores were derived for the Big 5 personality traits of agreeableness, extraversion, conscientiousness, openness and neuroticism using summary statistics from genome-wide association studies (GWAS).

FINDINGS

PSs for agreeableness [β= - 0.25, standard error (SE) = 0.054, P = 3.031e-6, ΔR²  = 0.008] and neuroticism (β=0.14, SE = 0.046, P = 0.0017, ΔR²  = 0.002) significantly predicted PGSI scores over and above included covariates (i.e. sex and first five ancestral principal components). PSs for agreeableness (β= - 0.20, SE = 0.056, P = 0.00036, ΔR²  = 0.003) and neuroticism, when interactions with age were taken into account (β = 0.29, SE = 0.090, P = 0.002, ΔR²  = 0.004), also predicted DPG scores.

CONCLUSIONS

Polygenic contributions to low agreeableness and high neuroticism appear to predict two measures of disordered gambling (problem gambling severity index and life-time assessment of DSM-IV pathological gambling symptoms). Polygenic scores for neuroticism interact with age to suggest that the positive association becomes stronger from adolescence through young adulthood.

A Comparison of Two GameSense Implementation Approaches: How Program Awareness and Engagement Relate to Gambling Beliefs and Behaviors

Despite the size and scope of responsible gambling (RG) programs in the U.S., relatively few studies have evaluated these programs. Using survey data from 4795 subscribers to a casino loyalty program, we examined respondents' awareness of and engagement with the GameSense RG program, and gambling beliefs and behaviors. We compared how differences in the implementation structure and visibility of the GameSense program (i.e., state-regulated with a standalone, branded GameSense center vs. corporate-integrated as part of loyalty program desks) was associated with GameSense awareness and engagement, perceptions of gambling operator RG practices, three Positive Play subscales (i.e., behavior, personal responsibility, and gambling literacy), understanding of gambling concepts, and use of RG strategies. More respondents who had visited the property with a state-regulated, branded center were aware of GameSense (36.5%), compared to respondents who visited other properties (7.4%). Perceptions of the operator's RG practices were generally high for all respondents. Multivariate analyses revealed no relationship between GameSense awareness and gambling belief or behavior outcomes, yet showed that respondents who picked up a GameSense brochure used slightly more RG strategies. Our findings suggest that the visibility of an RG program might influence program awareness and engagement but not certain RG-related behavioral outcomes.

The structure and subtypes of gambling activities: Genetic, psychiatric and behavioral etiologies of gambling frequency

The multitude of gambling activities has given rise to heterogeneous ways of analyzing these behaviors and may partially underlie the lack of replication in gambling research. The current study used complementary analyses to investigate the structure, typology and etiology of gambling behaviors in a discovery sample of 2,116 twins (54.86% female; M_age = 24.90) and a replication sample of 619 siblings (30.37% female; M_age = 28.00). Our approach was twofold. First, we used confirmatory factor analyses to investigate the structure across the frequency of eight gambling activities. Second, we used factor mixture models to identify gambling frequency subtypes. We assessed associations with gambling frequency as well as conducted genetically informed analyses to estimate the role of genetic and environmental influences. Across samples, a two-factor model fit the data best, with a Common Gambling factor influencing all activities and a separate factor for Skill Gambling. Our study identified four gambling frequency subtypes, which resembled the typology from the Pathways Model. We found distinct demographic, psychiatric, behavioral and genetic risk profiles for the different gambling factors and subtypes with robust associations observed for male sex, risk-taking, sensation seeking, alcohol dependence and problem gambling. Controlling for shared genetic and environmental influences (via co-twin control modeling), we found that sensation seeking directly increased Common Gambling frequency. In sum, we illustrated the utility of multi-dimensional statistical techniques for disentangling the structure and typology from complex multivariate gambling data.

Where Do Gambling Problems Fit in the Structure of Psychopathology During Emerging Adulthood?

Research suggests major mental disorders co-occur at higher than chance levels. In adult samples, a two factor structure emerges when modeling the higher order structure of psychopathology. Specifically, disorders tend to co-aggregate into two dimensions: Internalizing (depression and anxiety) and Externalizing (acting out, impulsive, and addictive) disorders. Despite this large body of evidence, few studies have integrated problem gambling into this overall model. We used confirmatory factor analysis to model how the symptom count of gambling fits into the structure of psychopathology in a large, community based young adult twin sample of men and women (age 24; N=1329). Twins were assessed via in-person, structured diagnostic interviews on disorders including: Major Depression, Phobias, Post-Traumatic Stress Disorder and Anxiety Disorders (internalizing) and Substance Use Disorders, Gambling Problems (self-report), and Antisocial Behaviors (externalizing). The data were fit to a two-factor structure, with gambling symptoms loading most highly on externalizing, rather than internalizing. The problem gambling loadings did not differ by sex. Implications of these findings suggest that during emerging adulthood gambling problems are best classified and conceptualized in the realm of externalizing disorders for both males and females. Results also suggest prevention and intervention efforts be aimed at young adults who exhibit commonly co-occurring psychopathology.

Genetic and environmental influences on gambling disorder liability: a replication and combined analysis of two twin studies

BACKGROUND

Gambling disorder (GD), recognized in Diagnostic and Statistical Manual of Mental Disorders, Version 5 (DSM-5) as a behavioral addiction, is associated with a range of adverse outcomes. However, there has been little research on the genetic and environmental influences on the development of this disorder. This study reports results from the largest twin study of GD conducted to date.

METHODS

Replication and combined analyses were based on samples of 3292 (mean age 31.8, born 1972-79) and 4764 (mean age 37.7, born 1964-71) male, female, and unlike-sex twin pairs from the Australian Twin Registry. Univariate biometric twin models estimated the proportion of variation in the latent GD liability that could be attributed to genetic, shared environmental, and unique environmental factors, and whether these differed quantitatively or qualitatively for men and women.

RESULTS

In the replication study, when using a lower GD threshold, there was evidence for significant genetic (60%; 95% confidence interval (CI) 45-76%) and unique environmental (40%; 95% CI 24-56%), but not shared environmental contributions (0%; 95% CI 0-0%) to GD liability; this did not significantly differ from the original study. In the combined analysis, higher GD thresholds (such as one consistent with DSM-5 GD) and a multiple threshold definitions of GD yielded similar results. There was no evidence for quantitative or qualitative sex differences in the liability for GD.

CONCLUSIONS

Twin studies of GD are few in number but they tell a remarkably similar story: substantial genetic and unique environmental influences, with no evidence for shared environmental contributions or sex differences in GD liability.

Has the Genetic Contribution to the Propensity to Gamble Increased? Evidence From National Twin Studies Conducted in 1962 and 2002

Social changes, such as the expansion of legal forms of gambling, can influence not only the prevalence of gambling, but can also shape the relative importance of genetic and environmental contributions to individual differences in the propensity to gamble. In the present study, I examined differences in the prevalence and in the relative contribution of genetic and environmental factors to gambling involvement in the United States in 1962 versus 2002. The data came from two sources: (1) a survey of 839 17-year-old same-sex twin pairs from the National Merit Scholarship Qualifying Test twin study, and (2) an interview of 477 18- to 26-year-old same-sex twin pairs from Wave III of the National Longitudinal Study of Adolescent to Adult Health. Similar measures of gambling participation were included in the two studies. Evidence for a genotype-by-time interaction was evaluated by testing whether the contribution of genetic influences was greater in the more recently born cohort of twins. Despite the major changes in the gambling landscape over the intervening 40 years, there was no evidence for such an interaction. The contribution of genetic factors and environmental factors did not significantly differ and there was no evidence for genetic influences at either time point. Instead, the variation in the propensity to gamble was explained nearly equally by common and unique environmental factors. Explanations for this surprising finding are discussed.