Electroencephalogram-Driven Machine-Learning Scenario for Assessing Impulse Control Disorder Comorbidity in Parkinson's Disease Using a Low-Cost, Custom LEGO-Like Headset.

Patients with Parkinson's disease (PD) may develop cognitive symptoms of impulse control disorders (ICDs) when chronically treated with dopamine agonist (DA) therapy for motor deficits. Motor and cognitive comorbidities critically increase the disability and mortality of the affected patients. This study proposes an electroencephalogram (EEG)-driven machine-learning scenario to automatically assess ICD comorbidity in PD. We employed a classic Go/NoGo task to appraise the capacity of cognitive and motoric inhibition with a low-cost, custom LEGO-like headset to record task-relevant EEG activity. Further, we optimized a support vector machine (SVM) and support vector regression (SVR) pipeline to learn discriminative EEG spectral signatures for the detection of ICD comorbidity and the estimation of ICD severity, respectively. With a dataset of 21 subjects with typical PD, 9 subjects with PD and ICD comorbidity (ICD), and 25 healthy controls (HC), the study results showed that the SVM pipeline differentiated subjects with ICD from subjects with PD with an accuracy of 66.3% and returned an around-chance accuracy of 53.3% for the classification of PD versus HC subjects without the comorbidity concern. Furthermore, the SVR pipeline yielded significantly higher severity scores for the ICD group than for the PD group and resembled the ICD vs. PD distinction according to the clinical questionnaire scores, which was barely replicated by random guessing. Without a commercial, high-precision EEG product, our demonstration may facilitate deploying a wearable computer-aided diagnosis system to assess the risk of DA-triggered cognitive comorbidity in patients with PD in their daily environment.

Assessment of subjective sleep quality and issues in aggression: Intermittent Explosive Disorder compared with psychiatric and healthy controls.

BACKGROUND: While prior research has linked clinical sleep issues and aggression, little is known about how clinical sleep issues among individuals with Intermittent Explosive Disorder (IED), which is characterized by a pervasive pattern of impulsive aggression and associated with consequences across multiple life-domains. The present study aims to examine clinical sleep issues among individuals with IED in contrast to individuals with other psychopathology and healthy controls. METHODS: 257 adults, including 100 healthy controls, 85 psychiatric controls and 72 individuals with IED, took part in this study. Participants completed the Structured Clinical Interview for DSM-V Diagnoses, Assessment of clinical sleep issues included the Pittsburgh Sleep Quality Inventory (PSQI), obstructive sleep apnea (OSA) screening, and the Epworth Sleepiness Scale (ESS) as well as assessments of aggression and impulsivity. RESULTS: IED study participants reported significantly worse sleep quality, increased sleep latency, greater daytime sleepiness and symptoms of OSA. Daytime sleepiness and sleep quality was correlated with impulsivity and aggression. CONCLUSIONS: This study suggests that individuals with IED have clinically relevant sleep anomalies, and that these are directly associated with measures of impulsivity and aggression. Clinicians treating aggressive individuals are advised to assess and treat such individuals for sleep issues.

Twelve-month mental health service use in six countries of the Americas: A regional report from the World Mental Health Surveys.

AIMS: To provide cross-national data for selected countries of the Americas on service utilization for psychiatric and substance use disorders, the distribution of these services among treatment sectors, treatment adequacy and factors associated with mental health treatment and adequacy of treatment. METHODS: Data come from data collected from 6710 adults with 12 month mental disorder surveys across seven surveys in six countries in North (USA), Central (Mexico) and South (Argentina, Brazil, Colombia, Peru) America who were interviewed 2001-2015 as part of the World Health Organization (WHO) World Mental Health (WMH) Surveys. DSM-IV diagnoses were made with the WHO Composite International Diagnostic Interview (CIDI). Interviews also assessed service utilization by the treatment sector, adequacy of treatment received and socio-demographic correlates of treatment. RESULTS: Little over one in four of respondents with any 12 month DSM-IV/CIDI disorder received any treatment. Although the vast majority (87.1%) of this treatment was minimally adequate, only 35.3% of cases received treatment that met acceptable quality guidelines. Indicators of social-advantage (high education and income) were associated with higher rates of service use and adequacy, but a number of other correlates varied across survey sites. CONCLUSIONS: These results shed light on an enormous public health problem involving under-treatment of common mental disorders, although the problem is most extreme among people with social disadvantage. Promoting services that are more accessible, especially for those with few resources, is urgently needed.

Impulse control disorders in Parkinson's disease: Review of pathophysiology, epidemiology, clinical features, management, and future challenges.

Impulsive-compulsive behavior (ICB) in Parkinson's disease (PD) suggests a combination of impulse control disorders (ICDs), such as pathological gambling, hypersexuality, compulsive eating, excessive buying, and compulsive behaviors, such as punding, dopamine dysregulation syndrome (DDS), hoarding, and hobbyism. Hypersexuality and gambling are common in male patients while compulsive buying is common in women patients. Recent studies reveal the prevalence of ICB to be more than 25% among the PD patients. The nigrostriatal, mesocortical, and mesolimbic dopaminergic pathways play a crucial role in the pathogenesis of ICDs in PD patients. The greater tonic release of dopamine creates a state of relative dopamine deficit and reduced reward sensation and impulsive behaviors. The major risk factors for ICB are the use of dopamine agonist (DA), male gender, young patient, depression, smoking, drug abuse, Parkin mutation, and family history of ICDs. Single nucleotide polymorphism in dopamine receptors D1, D2, and D3 also acts as a major risk factor. Questionnaire for impulsive-compulsive disorders in PD is the most widely adopted screening tool for the detection of ICB in PD. The major treatment for PD is to discontinue DAs and use prolonged release formulation of the DAs. The role of deep brain stimulation (DBS) and apomorphine in the treatment of ICB is still uncertain. Though DBS can reduce the risk of DDS, it can precipitate new ICBs such as hypersexuality.

Improvement of impulse control disorders associated with levodopa-carbidopa intestinal gel treatment in advanced Parkinson's disease.

Impulse control behaviors are a frequent comorbidity for patients with Parkinson's disease (PD). The objective of the present study was to evaluate the effectiveness levodopa-carbidopa intestinal gel (LCIG) therapy on impulse control disorders (ICDs) in patients with advanced PD. We conducted a multicenter, observational, and prospective (6 months follow-up) study that included consecutive PD patients assigned to LCIG through routine medical practice. Patients completed visits at baseline, 1, 3, and 6 months after percutaneous endoscopic gastrostomy procedure. The following outcomes were evaluated: presence and severity of ICDs and other neuropsychiatric disorders, sleep disturbances, patients' quality of life, and caregivers' burden. Sixty-two patients were included at baseline: mean age 72.2 years (SD ± 7.0), 42% women. Median duration of PD symptoms was 13.5 years (IQR 5.5-21.5) and median time with motor fluctuations was 5.0 years (IQR 1.0-9.0). Treatment with LCIG infusion was associated with progressive and significant improvements in ICDs symptoms over the study period (64.4% reduction in the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's disease-Rating Scale score). Psychotic and other neuropsychiatric symptoms were also significantly reduced, and patients' sleep quality and psychosocial function improved. Caregivers' burden remained unchanged. There was a significant improvement in the daily "Off" time [7.4 h (SD ± 4.0) vs 1.5 h (SD ± 1.8); p < 0.0001] at the end of follow-up, whereas duration of dyskinesias was not affected. ICDs significantly improved after 6-month LCIG treatment in a group of PD patients with mild-to-moderate neuropsychiatric disturbances.

Associations between the social organization of communities and psychiatric disorders in rural Asia.

PURPOSE: We provide rare evidence of factors producing psychiatric variation in a general population sample from rural South Asia. The setting is particularly useful for demonstrating that variations in the social organization of communities, often difficult to observe in rich countries, are associated with important variations in mental health. METHODS: Clinically validated survey measures are used to document variation in psychiatric disorders among 401 adults. This sample is chosen from a systematic sample of the general population of rural Nepal, in a community-level-controlled comparison design. Multilevel logistic regression is used to estimate multivariate models of the association between community-level nonfamily social organization and individual-level psychiatric disorders. RESULTS: Schools, markets, health services and social support groups each substantially reduce the odds of depression, post-traumatic stress disorder (PTSD), intermittent explosive disorder and anxiety disorders. Associations between schools, health services and social support groups and depression are statistically significant and independent of each other. The association between access to markets and PTSD is statistically significant and independent of other social organization and support groups. CONCLUSIONS: Community integration of some nonfamily social organizations promotes mental health in ways that may go unobserved in settings with many such organizations. More research on the mechanisms producing these associations is likely to reveal potential avenues for public policy and programs to improve mental health in the general population.

Associations between subjective social status and DSM-IV mental disorders: results from the World Mental Health surveys.

IMPORTANCE: The inverse social gradient in mental disorders is a well-established research finding with important implications for causal models and policy. This research has used traditional objective social status (OSS) measures, such as educational level, income, and occupation. Recently, subjective social status (SSS) measurement has been advocated to capture the perception of relative social status, but to our knowledge, there have been no studies of associations between SSS and mental disorders. OBJECTIVES: To estimate associations of SSS with DSM-IV mental disorders in multiple countries and to investigate whether the associations persist after comprehensive adjustment of OSS. DESIGN, SETTING, AND PARTICIPANTS: Face-to-face cross-sectional household surveys of community-dwelling adults in 18 countries in Asia, South Pacific, the Americas, Europe, and the Middle East (N=56,085). Subjective social status was assessed with a self-anchoring scale reflecting respondent evaluations of their place in the social hierarchies of their countries in terms of income, educational level, and occupation. Scores on the 1 to 10 SSS scale were categorized into 4 categories: low (scores 1-3), low-mid (scores 4-5), high-mid (scores 6-7), and high (scores 8-10). Objective social status was assessed with a wide range of fine-grained objective indicators of income, educational level, and occupation. MAIN OUTCOMES AND MEASURES: The Composite International Diagnostic Interview assessed the 12-month prevalence of 16 DSM-IV mood, anxiety, and impulse control disorders. RESULTS: The weighted mean survey response rate was 75.2% (range, 55.1%-97.2%). Graded inverse associations were found between SSS and all 16 mental disorders. Gross odds ratios (lowest vs highest SSS categories) in the range of 1.8 to 9.0 were attenuated but remained significant for all 16 disorders (odds ratio, 1.4-4.9) after adjusting for OSS indicators. This pattern of inverse association between SSS and mental disorders was significant in 14 of 18 individual countries, and in low-, middle-, and high-income country groups but was significantly stronger in high- vs lower-income countries. CONCLUSIONS AND RELEVANCE: Significant inverse associations between SSS and numerous DSM-IV mental disorders exist across a wide range of countries even after comprehensive adjustment for OSS. Although it is unclear whether these associations are the result of social selection, social causation, or both, these results document clearly that research relying exclusively on standard OSS measures underestimates the steepness of the social gradient in mental disorders.

Impulse control and related disorders in Mexican Parkinson's disease patients.

BACKGROUND: Impulse control disorders (ICDs) are a relatively recent addition to the behavioral spectrum of PD-related non-motor symptoms. Social and economic factors may play a role on the ICD phenotype of PD patients. OBJECTIVE: The aim of this study is to determine the prevalence and characterize the clinical profile of ICDs in a sample of low-income, low-education PD patients with no social security benefits from a Latin American country. METHODS: We included 300 consecutive PD patients and 150 control subjects. The presence of ICD and related disorders was assessed using a structured interview. After the interview and neurological evaluation were concluded, all subjects completed the Questionnaire for Impulsive-compulsive Disorders in Parkinson's Disease-Rating Scale (QUIP-RS). RESULTS: Regarding ICDs and related disorders (hobbyism-punding), 25.6% (n = 77) of patients in the PD group and 16.6% (n = 25) in the control group fulfilled criteria for at least one ICD or related disorder (p = 0.032). There was a statistically significant difference in the QUIP-RS mean score between PD and control subjects (5.6 ± 9.7 and 2.7 ± 4.21, p = 0.001). The most common ICD was compulsive eating for both PD (8.6%) and control (2.6%) groups. CONCLUSIONS: The results of this study confirm that for this population, symptoms of an ICD are significantly more frequent in PD subjects than in control subjects. Nevertheless, socioeconomic differences may contribute to a lower overall frequency and distinct pattern of ICDs in PD patients compared with what has been reported in other countries.

Intermittent explosive disorder amongst women in conflict affected Timor-Leste: associations with human rights trauma, ongoing violence, poverty, and injustice.

INTRODUCTION: Women in conflict-affected countries are at risk of mental disorders such as posttraumatic stress disorder and depression. No studies have investigated the association between experiences of abuse and injustice and explosive anger amongst women in these settings, and the impact of anger on women's health, family relationships and ability to participate in development. METHODS: A mixed methods study including an epidemiological survey (n = 1513, 92.6% response) and qualitative interviews (n = 77) was conducted in Timor-Leste. The indices measured included Intermittent Explosive Disorder, posttraumatic stress disorder; severe distress; days out of role (the number of days that the person was unable to undertake normal activities); gender-specific trauma; conflict/violence; poverty; and preoccupations with injustice. RESULTS: Women with Intermittent Explosive Disorder (n = 184, 12.2%) were more disabled than those without the disorder (for >5 days out of role, 40.8% versus 31.5%, X(2) (2) = 12.93 p = 0.0016). Multivariable associations with Intermittent Explosive Disorder, controlling for the presence of PTSD, psychological distress and other predictors in the model, included the sense of being sick (OR 1.73; 95% CI 1.08-2.77); victimization as a result of helping the resistance movement (OR 2.33, 95% CI 1.48-3.68); war-related trauma specific to being a woman (OR 1.95, 95%, CI 1.09-3.50); ongoing family violence and community conflict (OR 1.88, 95% CI 1.27-2.77); extreme poverty (OR 1.23, 95%, CI 1.08-1.39); and distressing preoccupations with injustice (relating to 2/3 historical periods, OR 2.10, 95% CI 1.35-3.28). In the qualitative study, women elaborated on the determinants of anger and its impact on their health, family and community functioning, child-rearing, and capacity to engage in development. Women reflected on the strategies that might help them overcome their anger. CONCLUSIONS: Intermittent Explosive Disorder is prevalent and disabling amongst women in conflict-affected Timor-Leste, impacting on their health, child-rearing and ability to participate fully in socio-economic development.

Prevalence of mental disorders and trends from 1996 to 2009. Results from the Netherlands Mental Health Survey and Incidence Study-2.

OBJECTIVE: To present prevalences of lifetime and 12-month DSM-IV mood, anxiety, substance use and impulse-control disorders from the second Netherlands Mental Health Survey and Incidence Study (NEMESIS-2), and to compare the 12-month prevalence of mood, anxiety and substance use disorders with estimates from the first study (NEMESIS-1). METHOD: Between November 2007 and July 2009, a nationally representative face-to-face survey was conducted using the Composite International Diagnostic Interview 3.0 among 6,646 subjects aged 18-64. Trends in 12-month prevalence of mental disorders were examined with these data and NEMESIS-1 data from 1996 (n = 7,076). RESULTS: Lifetime prevalence estimates in NEMESIS-2 were 20.2% for mood, 19.6% for anxiety, 19.1% for substance use disorder and 9.2% for impulse-control disorder. For 12-month disorders, these figures were 6.1, 10.1, 5.6 and 2.1%, respectively. Between 1996 and 2007-2009, the 12-month prevalence of anxiety and substance use disorder did not change. The prevalence of mood disorder decreased slightly but lost significance after controlling for differences in sociodemographic variables between the two studies. CONCLUSION: This study shows that in the Netherlands mental disorders are prevalent. In about a decade, no clear change in mental health status was found.

Demographic and social variables associated with problem gambling among men and women in Canada.

Knowledge of demographic and social correlates of problem gambling among men and women in general population samples is limited. Such research is important for identifying individuals who may become problem gamblers. The current research used a gender-stratified analysis using logistic regression models in a nationally representative sample to identify correlates of problem gambling among men and women. Data were from the Canadian Community Health Survey Cycle 1.2 (CCHS 1.2; data collected in 2002; response rate 77%). The 12-month prevalence of problem gambling among men and women who endorsed gambling in the past year was 4.9% and 2.7%, respectively. For women, increased odds of problem gambling was associated with middle age, middle to low levels of income, a high school diploma or less, being never-married, higher levels of life stress, and negative coping abilities. For men, being aged 70 or greater decreased the odds of problem gambling, while being separated, widowed, or divorced, lower levels of social support, and negative coping abilities increased the odds of problem gambling. These findings have important public health implications for identifying men and women who may be more likely to become problem gamblers in the general population.

A survey of pharmacy students' experiences with gambling.

OBJECTIVES: To assess gambling among pharmacy students using the South Oaks Gambling Screen (SOGS). METHODS: Six hundred fifty-eight pharmacy students enrolled at Creighton University were surveyed to determine the extent and characteristics of their gambling. RESULTS: Four hundred eighty-eight students (74.2%) participated (mean age was 26.6 years and 63.4% were female). Almost two-thirds (63.1%) gambled at least once during the past 12 months. Slightly more than 16% (80) of students were identified as "at-risk" (SOGS scores of 1 to 2). Another 5% (24) were likely to be problem gamblers (SOGS scores of 3 to 4), while 1% of students were identified as probable pathological gamblers (SOGS scores > or = 5). Students who gambled were significantly more likely than non-gamblers to be single males. Gamblers with a score > or = 1were significantly more likely to report gambling had affected their relationships with others, compared to casual gamblers. CONCLUSIONS: Gambling is a common activity among pharmacy students. While the incidence of problem gambling is relatively small, the percentage of our students who may be at-risk for gambling-related problems is noteworthy.

Follow-up study of female delinquent adolescents in a detention centre: effectiveness of psychiatric intervention as a mental health service.

RESULTS: of previous studies suggest that many female offenders have co-morbid psychiatric disorders, which require mental health services. However, few longitudinal studies examined subjects during incarceration or detention. This study compares depressive symptoms, abnormal eating behaviour and impulsivity before release from a detention centre and after incarceration, thereby indicating the effectiveness of psychiatric intervention in a Japanese detention centre. METHOD: Of 64 young women, 36 were followed up. Self-report measures were used to assess depression, eating behaviour and impulsivity after incarceration and one month before release. RESULT: s: Of the 36 participants, nine were diagnosed using the MINI-kids as needing mental health services. Those who received psychiatric intervention were diagnosed as having major depression and/or post-traumatic stress disorder. Significant main effects of intervention and effects of time were shown in the DSD. The EAT-26 score demonstrated the significance of the effects of time and interaction. In the BIS-11 scores, neither intervention nor time showed significant effects. CONCLUSIONS: Results of this study showed that the time course and psychiatric intervention contributed to recovery of depression and therapeutic intervention. The time course might reduce eating problems. Psychiatric intervention might be necessary for female juvenile detainees, which presents an important issue for future studies.

[Assessment of functional and dysfunctional impulsivity in substance-addicted patients by means of Dickman's Inventory]. / Evaluación de la impulsividad funcional y disfuncional en adictos a sustancias mediante el Inventario de Dickman.

Impulsivity is a dispositional trait consistently linked to addiction. Nevertheless, Dickman proposed two different types of impulsivity, a functional variant and another, dysfunctional one. Almost all studies in addiction have exclusively explored the dysfunctional facet of impulsivity. The main purpose of this study was to check the applicability of the Dickman Impulsivity Inventory to explore both types of impulsivity in addicted individuals. We applied a Spanish version of the inventory and studied its psychometric properties. We found adequate internal consistency, construct validity and convergence of measures with related instruments, both in non-clinical (N = 398) and in treated substance-addicted (diacetylmorphine, cocaine, alcohol and cannabis; N = 140) samples. Addicted individuals did not differ from the non-clinical population in their functional impulsivity, but we found a great effect size (eta2p = 0.35) in the differences when exploring the dysfunctional type, with higher scores in addicts. Dysfunctional impulsivity was related to dysexecutive symptoms (r2 = 0.39), and personality traits such as Novelty Seeking (r2 = 0.57), but not with the Exploratory Excitability subdimension (r2 = 0.01), this latter being more closely related to functional impulsivity (r2 = 0.16). Data support the usefulness of this inventory to estimate types of impulsivity related to the prevention and treatment of addictive behaviors.

Pathological gambling and criminality.

PURPOSE OF REVIEW: To review research results on the relationship between pathological gambling and criminality, published in 2007 and 2008, in English and in Spanish. RECENT FINDINGS: An important association between pathological gambling and criminality was confirmed in populations of anonymous gamblers, helpline callers and substance abusers. Helplines provide a timely service to gamblers who have not reached the maximum stages in the development of a pathological gambling pattern. Pathological gambling is associated with violence in couples and dysfunctional families. Inversely, violence is also an antecedent promoting vulnerability toward pathological gambling. Impulsiveness shows diverse relationships with pathological gambling and violence as well. A pathological gambler's involvement in crime is exceptionally considered without responsibility by justice, but it may be an indicator of the disorder severity and the need for special therapeutic tactics. SUMMARY: While reviewing the present study, research work was published that contributed to a better understanding of the association between pathological gambling and criminality and went further into their complex relationship and the formulation of explanatory models related to impulsiveness.

Impulse control disorders in Parkinson's disease: definition, epidemiology, risk factors, neurobiology and management.

There is increasing awareness that impulse control disorders (ICDs), including pathological gambling, hyper-sexuality, compulsive eating and buying, can occur as a complication of Parkinson's disease (PD). In addition, other impulsive or compulsive disorders have been reported to occur, including dopamine dysregulation syndrome (DDS) and punding. Case reports and prospective studies have reported an association between ICDs and the use of dopamine receptor agonists at higher doses, and DDS has been associated with L-dopa at higher doses or short-acting dopamine receptor agonists. Risk factors for ICDs include male sex, younger age or younger age at PD onset, a pre-PD history of ICD symptoms, history of substance use or bipolar disorder, and a personality profile characterized by impulsiveness. The management of clinically significant ICD symptoms should consist of modifications to dopamine replacement therapy, particularly dopamine receptor agonists, which is usually associated with an improvement of ICDs. There is no empirical evidence supporting the use of psychiatric drugs for ICDs in PD. Functional neuroimaging studies such as functional MRI and PET can investigate in vivo the neurobiological basis of these pathological behaviours.

Multidimensional social control variables as predictors of drunkenness among French adolescents.

BACKGROUND: Previous studies of the determinants of drunkenness among youth investigated the contribution of a limited range of variables measuring social control. For the first time in France, this study including 1295 participants aged 14-19 years aimed at assessing the relative contribution of a broad range of multidimensional variables relating to social control such as parental and school functioning, conventional and religious beliefs, and activity level, in a single model predicting self-reported drunkenness episodes. METHODS: A logistic regression model based on a survey involving nearly 50 measures selected at the first step was conducted using a backward elimination procedure to identify the significant predictors of drunken experience controlling for age, gender and SES among a sample of French adolescents. RESULTS: We found a protective effect of attachment and commitment to institutions in drunkenness experience among youth. Previous findings on parental variables were confirmed with qualifications, whereas the effect of religion was limited. The negative role of sport practice and impulsivity was also emphasized for some participants.

Sociodemographic correlates of internet gambling: findings from the 2007 british gambling prevalence survey.

This study provides the first analysis ever made of a representative national sample of Internet gamblers. Using participant data from the 2007 British Gambling Prevalence Survey (n = 9,003 adults aged 16 years and over), all participants who had gambled online, bet online, and/or used a betting exchange in the last 12 months (n = 476) were compared with all other gamblers who had not gambled via the Internet. Overall, results showed a number of significant sociodemographic differences between Internet gamblers and non-Internet gamblers. When compared to non-Internet gamblers, Internet gamblers were more likely to be male, relatively young adults, single, well educated, and in professional/managerial employment. Further analysis of DSM-IV scores showed that the problem gambling prevalence rate was significantly higher among Internet gamblers than among non-Internet gamblers. Results suggest that the medium of the Internet may be more likely to contribute to problem gambling than gambling in offline environments.

Links between casino proximity and gambling participation, expenditure, and pathology.

Two studies investigated the relationship between casino proximity and gambling participation, expenditure, and pathology. In Study 1, 8,842 participants were categorized into 1 of 4 driving distances from their home to the nearest casino in the province of Quebec: 0-100 km, 100.01-200 km, 200.01-300 km, or 300.01-981 km. In Study 2, 5,158 participants, who lived within a 100-km driving distance from the Montreal casino, were classified into 1 of 5 equidistant, 20-km driving distances. A survey company interviewed participants regarding their gambling habits. Results indicated a positive link between casino proximity and gambling participation (at the provincial and Montreal levels) and expenditure (at the provincial level only) but no link with the current prevalence rate of probable pathological gambling or of problem gambling. In a setting in which many types of gambling activities are available, casino proximity in itself does not appear to explain the rate of gambling-related problems. It is necessary to continue prospective research on exposure and adaptation theories as potential explanations for the development of pathological gambling.

Replication of low-risk gambling limits using canadian provincial gambling prevalence data.

A set of low-risk gambling limits were recently produced using Canadian epidemiological data on the intensity of gambling behavior and related consequences (Currie et al. Addiction 101:570-580, 2006). The empirically derived limits (gambling no more than two to three times per month, spending no more than $501-$100o CAN per year or no more than 1% of gross income spent on gambling) accurately predicted risk of gambling-related harm after controlling for other risk factors. The present study sought to replicate these limits on data collected in three independently conducted Canadian provincial gambling surveys. Dose-response curves and logistic regression analyses were applied to gambling prevalence data collected in surveys conducted in 2001-2002 within the provinces of Alberta, British Columbia, and Ontario (combined sample N = 7,675). A comparable dose-response relationship between gambling intensity and risk of harm was found in each province. The optimal thresholds for defining an upper limit of low-risk gambling were similar across the three provinces despite variations in the availability and organization of legalized gambling opportunities within each region. These results provide additional evidence supporting the validity of the low-risk gambling limits. Quantitative limits could be used to augment existing responsible gambling guidelines.