Impulsivity predicts level of cognitive distortions in pathological gambling: preliminary data from the UK National Prob

1. Impulsivity predicts level of cognitive distortions in pathological gambling: preliminary data from the UK National Problem Gambling Clinic Rosanna Michalczuk1, HenriettaBowden-Jones2, Antonio Verdejo-Garcia3 and Luke Clark1 1 Behavioural and Clinical Neuroscience Institute, Department of Experimental Psychology, University of Cambridge. 2 Imperial College, London 3 Department of Clinical Psychology, University of Granada, Spain. Introduction Cognitive approaches to gambling have emphasised how distorted beliefs about chance, skill and probability cause the gambler to over-estimate their chances of winning during play. These distortions can be measured using the ‘think aloud’ technique, or more recently, using psychometric scales like the Gambling Related Cognitions Scale (Raylu & Oei 2004). Groups with disordered gambling experience higher levels of gambling distortions (e.g. Miller & Currie 2008). Other data have described elevated impulsivity in groups of problem gamblers. Impulsivity is a multi-faceted construct that can be assessed using self-report questionnaires or quantitative laboratory procedures. Prospective data indicate that impulsivity assessed with either approach can predict emergence of later gambling problems in adolescents (e.g. Vitaro et al 1999), but it is unclear how the different indices of impulsivity relate to one another or have differential associations with clinical variables. This study explored the relationship between different facets of impulsivity and the level of gambling-related cognitive distortions in a preliminary analysis of data from the National Problem Gambling Clinic, the first publicly-funded treatment service for problem gambling in the UK (launched in 2008). Methods Pathological Gamblers were recruited from the National Problem Gambling Clinic in London, U.K. This is the first publicly-funded (NHS) clinic for gambling problems in the UK. Opened in 2008, the clinic has received nearly 1000 referrals in two years. The present analysis is based upon an interim comparison of 30 gamblers attending the clinic, who met DSM-IV criteria for Pathological Gambling and scored above 8 on the Canadian Problem Gambling Index. These participants were compared against 30 healthy controls, recruited through community advertising. Groups did not differ in age, gender or education. Impulsivity was assessed using the UPPS-P scale (Cyders et al 2007), a self-report questionnaire that separates facets of sensation seeking, lack of premeditation, perseverance, and urgency. Urgency is defined as the tendency to commit impulsive acts during valenced mood states (positive urgency, negative urgency), and while recent data highlight the specific relevance of this dimension to addictive disorders, it has not been to date examined in pathological gamblers. The Kirby Monetary Choice Questionnaire (Kirby et al 1999) was used to assess delay discounting, as a test of impulsive choice (e.g. “Would you prefer £15 day or £35 in 13 days?”). Gambling-related cognitive distortions were assessed using the Gambling-Related Cognitions Scale (GRCS, Raylu & Oei 2004). Results Table 1: Demographic and clinical data Figure 2: Delay Discounting Rates in Pathological Gamblers vs Controls on Kirby’s Monetary Choice Questionnaire Figure 3: Increased discounting of future rewards predicts higher levels of gambling-related cognitive distortions Figure 1: Self-reported impulsivity on the UPPS Impulsivity scale in Pathological Gamblers vs Controls More impulsive More impulsive The pathological gamblers did not differ from controls on the UPPS-P sensation seeking subscale (t(59) = -0.77), but scored significantly higher on lack of premeditation (t(59)=2.39; p<0.05), lack of perseverance (t(59)=3.09; p<0.01), negative urgency (t(59)=6.98; p<0.001) and positive urgency (t(59)= 5.57; p<0.001). However, effect sizes (Cohen’s d) revealed markedly stronger effects for the two urgency subscales (negative urgency d=1.427; positive urgency d=1.784) in comparison to the narrow impulsivity subscales (lack of premeditation d=0.616 and lack of perseverance d=0.791) , suggesting that urgency may be a particularly relevant construct in PG PG scored higher on the GRCS than controls (t59=6.87,p<0.001) Within the gamblers, discounting on the Kirby Questionnaire (ln K parameter) was highly correlated with the GRCS score (r=0.67,p<0.001). The discounting rate was not correlated significantly with any of the UPPS-P subscales (maximum r value for positive urgency r=0.33, p=.08). In a multiple regression model with GRCS as the dependent variables, and discounting rate, positive urgency and negative urgency as predictors, only delay discounting was significantly associated with the level of distortions (overall R2=0.45). Delay discounting was assessed using two methods: 1) K values were extracted, assuming an underlying hyperbolic function. ANOVA revealed a significant main effect of group (F(1,56)=8.86, p=.004), and an overall magnitude effect (F(1.7, 94.2)=20.3, p<.001). 2) Area Under Curve for the discounting function does not assume any underlying mathematical model, and confirmed steeper discounting in the PG group (t55=2.36, p=.021) Conclusions There were significant elevations in impulsivity in treatment-seeking Pathological Gamblers on two measures: on the UPPS self-report questionnaire, the PG group showed particularly strong effects on Urgency; the tendency to commit impulsive acts in positive or negative mood states. There were no group differences in sensation seeking. Urgency is a risk factor for illicit drug use and recreational gambling, as well as other risky behaviors (see Cyders et al). Group differences in positive and negative urgency is consistent with known motivational influences in PG: gamblers may be motivated by excitement that in turn reinforces continued play, but also to alleviate unpleasant mood states . The PG group displayed steeper discounting rates of future monetary rewards on a test of impulsive (inter-temporal) choice, confirming previous findings (e.g Petry 2001). Discounting behavior was not significantly related to impulsivity on the questionnaire. This highlights the multi-factorial nature of impulsivity, and suggests that delay discounting and trait urgency tap distinct phenotypes relevant to pathological gambling. As anticipated, the PG group scored higher on an index of gambling-related cognitive distortions, the GRCS. Within the gambling group, steeper delay discounting was highly correlated with the level of cognitive distortions, and the UPPS urgency subscales did not enter a regression model as significant predictors after entering the discount rate. As such, impulsive choice (discounting) may convey susceptibility to the distortions of skill, chance and probability that characterise PG, and which may be targeted in cognitive therapies. These data indicate some linkage between etiological accounts of disordered gambling based on impulsivity and cognitive distortions. References Cyders M, et al (2007). Integration of impulsivity and positive mood to predict risky behavior: Development and validation of a measure of positive urgency. Psychological Assessment19:107–118. Kirby K, Petry N, Bickel W (1999). Heroin addicts discount delayed rewards at higher rates than non-drug using controls. Journal of Experimental Psychology: General. 128(1):78-87. 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