Revisión de la asociación entre obesidad y TDAH / Review of the association between obesity and ADHD

El sobrepeso y la obesidad son definidas por la OMS (Organización Mundial de la Salud) como una acumulación anormal o excesiva de grasa que es perjudicial para la salud. Por otro lado, el TDAH (Trastorno por Déficit de Atención e Hiperactividad) se define por la presencia de dificultades atencionales, pobre regulación de la actividad motora y un bajo control de los impulsos 2. La asociación entre Obesidad y TDAH se investiga sistemáticamente desde hace doce años. En este artículo de revisión se expondrán estudios previos que son relevantes a la hora de establecer esta relación, se revisarán las distintas hipótesis neurobiológicas que asocian Obesidad con TDAH y se planteará su asociación con las adicciones

Excess weight and obesity are defined by the WHO (World Health Organization) as abnormal or excessive fat accumulation that is unhealthy.1 On the other hand, attention deficit hyperactivity disorder (ADHD) is defined by the presence of attention difficulties, poor motor regulation activity, and low impulse control.2 The association between obesity and ADHD has been systematically investigated for twelve years. In this review article, previous studies that were relevant in establishing this relation are examined.Neurobiological hypotheses about the relation between obesity and ADHD are reviewed, and an association with addictions is considered

Differences between non-suicidal self injury and suicide attempt in Chinese adolescents.

PURPOSE: Self-harm behaviors are predominant health risks among adolescents. This study aimed to elucidate the lifetime prevalence and differences in social psychological factors between non-suicidal self-injury (NSSI) and suicide attempt (SA) among Chinese adolescents. METHOD: Data were collected from 2131 middle school students with a mean age of 13.92 (SD 1.63) years (49.1% girls). Participants were asked to self-report NSSI and SA over their lifetime. Post hoc tests pairwise comparisons and multinomial logistic regression analyses were conducted to investigate differences and similarities between subjects with NSSI and attempted suicide. RESULTS: The prevalence of lifetime NSSI and SA endorsed by the participants were 23.2% and 3.2%, respectively, and the co-occurrence of these two behaviors (NSSI+SA) was reported to 2.3%. Boys were comparable with girls in the prevalence rate of NSSI, but not in the rate of SA. It revealed that single-child was not the risk factor for self-harm behavior in Mainland China, but lower higher family cohesion and adaptability. Factors that distinguished the NSSI+SA group from the NSSI only group were female gender, lower grade, impulsivity, health risk behaviors and family cohesion. Being female gender, single-parent family, depressive symptoms and impulsivity were factors differentiating attempted suicide from NSSI. CONCLUSIONS: Our findings suggest that Chinese adolescents engaging both in NSSI and SA had severe suicidal attempts and were different from those who engaged in NSSI alone.

Time horizons and substance use among African American youths living in disadvantaged urban areas.

Transitioning from adolescence to full-fledged adulthood is often challenging, and young people who live in disadvantaged urban neighborhoods face additional obstacles and experience disproportionately higher negative outcomes, including substance abuse and related risk behaviors. This study investigated whether substance use among African Americans ages 15 to 25 (M=18.86 years) living in such areas was related to present-dominated time perspectives and higher delay discounting. Participants (N=344, 110 males, 234 females) living in Deep South disadvantaged urban neighborhoods were recruited using Respondent Driven Sampling, an improved peer-referral sampling method suitable for accessing this hard-to-reach target group. Structured field interviews assessed alcohol, tobacco, and illicit drug use and risk/protective factors, including time perspectives (Zimbardo Time Perspective Inventory [ZTPI]) and behavioral impulsivity (delay discounting task). As predicted, substance use was positively related to a greater ZTPI orientation toward present pleasure and a lower tendency to plan and achieve future goals. Although the sample as a whole showed high discounting of delayed rewards, discount rates did not predict substance use. The findings suggest that interventions to lengthen time perspectives and promote enriched views of future possible selves may prevent and reduce substance use among disadvantaged youths. Discontinuities among the discounting and time perspective variables in relation to substance use merit further investigation.

Mood disorders after TBI.

In this article, we examine the epidemiology and risk factors for the development of the most common mood disorders observed in the aftermath of TBI: depressive disorders and bipolar spectrum disorders. We describe the classification approach and diagnostic criteria proposed in the fifth edition of the Diagnostic and Statistical Manual for Mental Disorders. We also examine the differential diagnosis of post-TBI mood disorders and describe the mainstay of the evaluation process. Finally, we place a special emphasis on the analysis of the different therapeutic options and provide guidelines for the appropriate management of these conditions.

Is the residential combined (psychotherapy plus medication) treatment of patients with severe personality disorder effective in terms of suicidality and impulsivity?

The aim of this study was to compare the effectiveness of combined treatment-medication plus psychodynamic psychotherapy-and psychodynamic psychotherapy alone on the outcome variables of suicidality and impulsivity in a population of adult inpatients with severe personality disorder (SPD). This is a naturalistic-empirical (observational) study under the conditions of clinical practice (an intensive specialized inpatient psychotherapeutic program [SIPP]). The sample consisted of 33 inpatients with SPD who were allocated to two subgroups (groups A and B). The patients in group A received psychodynamic psychotherapy and adjunctive pharmacotherapy, whereas the patients in group B received multimodal psychodynamic psychotherapy only. A statistically significant reduction in suicidality score was observed in the patients in group A, whereas a tendency for significant reduction in impulsivity score was observed in group B after the SIPP termination. Pharmacotherapy combined with multimodal psychodynamic psychotherapy, always within the SIPP, seems more effective in the case of suicidality rather than impulsivity.

Correlates of traumatic brain injury among juvenile offenders: a multi-site study.

BACKGROUND: There is some evidence that antisocial individuals, including young delinquents, are significantly more likely than people in the general population to incur a traumatic brain injury (TBI). Extant studies are hampered by methodological limitations, such as small sample sizes, lack of control for confounding effects, and use of single sites and may lack representativeness. HYPOTHESIS: The hypothesis for this study is that young offenders with a history of TBI will not only be at higher risk of impulsivity and negative emotionality than their non-injured peers but also that those with TBI will have had more previous victimisation experiences. METHODS: Data from two sites (Philadelphia, PA and Phoenix, AZ) in a substantial longitudinal, prospective study - the Pathways to Desistance Study - were used to compare young people (average age 16 years) who reported TBI with those who did not. Independent variables were behavioural, criminogenic and psychosocial measures. RESULTS: Male youths were about twice as likely as young females to report TBI. Such injury was associated with higher impulsivity and negative emotion ratings, even after allowing for potentially confounding factors, including sex. In addition, TBI was independently associated with self-reported experience of victimisation. CONCLUSIONS/IMPLICATIONS: This extends the generalisability of earlier suggestions of a relationship between TBI and offending, and various factors thought likely to mediate the relationship. The implications are, thus, that it is likely to be of practical value to screen young people who get into the criminal justice system for a history of TBI, and thus to allow for more specific tailoring of interventions to reduce the range of associated problems, including likely reoffending.

Contribution of time of drinking onset and family history of alcohol problems in alcohol and drug use behaviors in Argentinean college students.

AIMS: The aim of the study was to analyze independent and potential interactive effects of age at drinking onset and family history of alcohol abuse on subsequent patterns of alcohol drinking, alcohol-related problems and substance use. METHODS: Participants were college students (60.3% females, mean age = 20.27 ± 2.54 years) from the city of Córdoba, Argentina. Several measures were used to assess alcohol, tobacco and drug use. The Spanish version of the Brief Young Adult Alcohol Consequences Questionnaire was used to assess alcohol-related problems. Factorial analyses of variance, or its non-parametric equivalent, were performed to explore differences in substance use behaviors and alcohol-related problems in subjects with early or late drinking onset and with or without family history of alcohol abuse. Chi-square tests were conducted to analyze the association between these two risk factors and categorical measures of alcohol, tobacco and drug use. RESULTS: Early onset of drinking was associated with amount of consumption of alcohol including up to hazardous levels, as well as tobacco and drug use. However, the frequency of alcohol problems and frequency of episodes of alcohol intoxication were only related to age of onset in those with a positive family history of alcohol problems. CONCLUSION: Delaying drinking debut is particularly important in the prevention of future alcohol problems in those adolescents who have a family history of such problems.

Impulsive and compulsive behaviors among Danish patients with Parkinson's disease: prevalence, depression, and personality.

INTRODUCTION: Dopaminergic medication administered to ameliorate motor symptoms of Parkinson's disease is associated with impulse control disorders, such as pathological gambling, hypersexuality, compulsive buying, and binge eating. Studies indicate a prevalence of impulse control disorders in Parkinson's disease of 6-16%. OBJECTIVE: To estimate the prevalence of impulsive and compulsive behaviors among Danish patients with Parkinson's disease and to explore the relation of such behavioral disorders to depression and personality. METHODS: 490 patients with Parkinson's disease (303 males), identified through the National Danish Patient Registry, were evaluated with: 1) the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease; 2) the Geriatric Depression Scale; and 3) the NEO-Personality Inventory. RESULTS: 176 (35.9%) patients reported impulsive and compulsive behaviors sometime during Parkinson's disease (current symptoms in 73, 14.9%). Hereof, 114 (23.3%) reported multiple behavioral symptoms. Patients with behavioral symptoms were significantly younger, were younger at PD onset, had longer disease duration, displayed more motor symptoms, and received higher doses of dopaminergic medication than patients without behavioral symptoms. Furthermore, they reported significantly more depressive symptoms and scored significantly higher on neuroticism and lower on both agreeableness and conscientiousness than patients without behavioral symptoms. CONCLUSION: A history of impulsive and compulsive behaviors are common in Danish patients with Parkinson's disease and have clinical correlates that may allow identification of patients at risk for developing these behaviors.

Impulsivity is associated with uric acid: evidence from humans and mice.

BACKGROUND: The ability to control impulses varies greatly, and difficulty with impulse control can have severe consequences; in the extreme, it is the defining feature of many psychiatric disorders. Evidence from disparate lines of research suggests that uric acid is elevated in psychiatric disorders characterized by high impulsivity, such as attention-deficit/hyperactivity disorder and bipolar disorder. The present research tests the hypothesis that impulsivity is associated with higher uric acid in humans and mice. METHODS: Using two longitudinal, nonclinical community samples (total n = 6883), we tested whether there is an association between uric acid and normal variation in trait impulsivity measured with the Revised NEO Personality Inventory. We also examined the effect of uric acid on behavior by comparing wild-type mice, which naturally have low levels of uric acid, with mice genetically modified to accumulate high levels of uric acid. RESULTS: In both human samples, the emotional aspects of trait impulsivity, specifically impulsiveness and excitement seeking, were associated with higher levels of uric acid concurrently and when uric acid was measured 3 to 5 years later. Consistent with the human data, the genetically modified mice displayed significantly more exploratory and novelty-seeking behavior than the wild-type mice. CONCLUSIONS: Higher uric acid was associated with impulsivity in both humans and mice. The identification of biological markers of impulsivity may lead to a better understanding of the physiological mechanisms involved in impulsivity and may suggest potential targets for therapeutic intervention.

Trait-aggressiveness and impulsivity: role of psychological resilience and childhood trauma in a sample of male prisoners.

BACKGROUND: One of the major challenges for research in the field of human aggression is the need to define the role of personality and trait-like dimensions, such as impulsivity and aggressiveness, in predisposing to violent behavior. AIMS: 1) To determine whether trait- aggressiveness and impulsivity may be associated with socio-demographic, clinical and crime history variables in a sample of male prisoners; 2) to detect any association of those traits with measures of early traumatic experiences and current resilience traits. METHODS: A sample of male prisoners (n = 1356) underwent the Brown-Goodwin Assessment for Lifetime History of Aggression (BGLHA) and the Barratt Impulsivity Scale (BIS). Axis I psychiatric disorders were also assessed. Early traumatic experiences and psychological resilience were detected respectively by the Childhood Trauma Questionnaire (CTQ) and the Connor-Davidson Resilience Scale (CD-RISC). Two non-linear logistic regression models were performed to test for the best predictors of trait-aggressiveness and impulsivity. RESULTS: Subjects with a history of substance use disorders and self-mutilation reported both higher BGLHA and BIS scores. Axis I disorders and suicide attempts were associated with aggressiveness, but not to impulsivity. A consistent correlation was found between BGLHA scores and early traumatic experiences. Resilience was positively correlated to impulsivity but not to aggressiveness scores. CONCLUSIONS: Our results support the view that aggressiveness and impulsivity are two different, albeit related trait-like dimensions of personality, having a different relationship with resilience, and, inferentially, a different impact over the development of psychiatric disorders.

Investigation of impulsivity in patients on dopamine agonist therapy for hyperprolactinemia: a pilot study.

The use of dopamine agonists (DAs) has been associated with increased impulsivity and impulse control disorders in several diseases, including Parkinson's disease. Such an effect of DAs on impulsivity has not been clearly characterized in hyperprolactinemic patients, where DAs are the mainstay of therapy. We studied the effects of DAs on impulsivity in hyperprolactinemic patients treated at a tertiary pituitary center, using validated psychometric tests. Cross-sectional study. Impulsivity was evaluated in 30 subjects, 10 hyperprolactinemic patients on DAs compared to two control groups; one comprising untreated hyperprolactinemic patients (n = 10) and a second group consisting of normoprolactinemic controls with pituitary lesions (n = 10). Measures of impulsivity included both self-report questionnaires as well as laboratory-based tasks. Hyperprolactinemic patients on DAs had a higher score (mean ± SD) in one self-report measure of impulsivity, the attention subscale of the Barratt Impulsiveness Scale (16.2 ± 2.7), as compared to the hyperprolactinemic control group (12.3 ± 2.5) and the normoprolactinemic group (14.7 ± 4.4) (p = 0.04). No statistically significant difference was found between groups with regards to the other impulsivity scales. In the DA-treated group, a correlation was observed between increased impulsivity (as assessed in the Experiential Discounting Task) and higher weekly cabergoline dose (r(2) = 0.49, p = 0.04). The use of DAs in hyperprolactinemic patients is associated with an increase in one aspect of impulsivity. This effect should be further characterized in larger, longitudinal studies.

Impulsivity, irritability, and depression: antidepressants.

Definitional and conceptual issues related to the symptoms of impulsivity, irritability, and depression are described. A brief overview of the relevant neurobiology of each symptom is then provided. General psychopharmacologic strategies to address these symptoms are explored. Finally, brief clinical vignettes are described along with specific pharmacologic information on commonly used agents.

Impulsivity and alcohol demand in relation to combined alcohol and caffeine use.

Problematic alcohol use among college students continues to be a prominent concern in the United States, including the growing trend of consuming caffeinated alcoholic beverages (CABs). Epidemiologically, CAB use is associated with incremental risks from drinking, although these relationships could be due to common predisposing factors rather than specifically due to CABs. This study investigated the relationship between CAB use, alcohol misuse, and person-level characteristics, including impulsive personality traits, delayed reward discounting, and behavioral economic demand for alcohol use. Participants were 273 regularly drinking undergraduate students. Frequency of CAB use was assessed over the past month. A multidimensional assessment of impulsivity included the UPPS-P questionnaire, which measures positive and negative urgency, premeditation (lack thereof), perseverance (lack thereof), and sensation seeking (Lynam, Smith, Whiteside, & Cyders, 2007), and a validated questionnaire-based measure of delayed reward discounting. Demand was assessed via a hypothetical alcohol purchase task. Frequency of CAB consumption was significantly higher in men than in women and was also associated with higher impulsivity on the majority of the UPPS-P subscales, steeper delayed reward discounting, and greater demand for alcohol. Significant correlations between CAB use and both alcohol demand and lack of premeditation remained present after including level of alcohol misuse in partial correlations. In a hierarchical linear regression incorporating demographic, demand, and impulsivity variables, CAB frequency continued to be a significant predictor of hazardous alcohol use. These results suggest that although there are significant associations between CAB consumption and gender, impulsivity, and alcohol demand, CAB use continues to be associated with alcohol misuse after controlling for these variables.

Prevalence of neurobehavioral, social, and emotional dysfunction in patients treated for childhood craniopharyngioma: a systematic literature review.

BACKGROUND: Craniopharyngiomas (CP) are locally invasive and frequently recurring neoplasms often resulting in neurological and endocrinological dysfunction in children. In addition, social-behavioral impairment is commonly reported following treatment for childhood CP, yet remains to be fully understood. The authors aimed to further characterize the prevalence of neurobehavioral, social, and emotional dysfunction in survivors of childhood craniopharyngiomas. MATERIALS AND METHODS: A systematic literature review was conducted in PubMed to identify studies formally assessing neurobehavioral, social, and emotional outcomes in patients treated for CP prior to 18 years of age. Studies published between the years 1990-2012 that reported the primary outcome (prevalence of neurobehavioral, social, emotional/affective dysfunction, and/or impaired quality of life (QoL)) in ≥ 10 patients were included. RESULTS: Of the 471 studies screened, 11 met inclusion criteria. Overall neurobehavioral dysfunction was reported in 51 of 90 patients (57%) with available data. Social impairment (i.e. withdrawal, internalizing behavior) was reported in 91 of 222 cases (41%). School dysfunction was reported in 48 of 136 patients (35%). Emotional/affective dysfunction was reported in 58 of 146 patients (40%), primarily consisting of depressive symptoms. Health related quality of life was affected in 49 of 95 patients (52%). Common descriptors of behavior in affected children included irritability, impulsivity, aggressiveness, and emotional outbursts. CONCLUSIONS: Neurobehavioral, social, and emotional impairment is highly prevalent in survivors of childhood craniopharyngioma, and often affects quality of life. Thorough neurobehavioral/emotional screening and appropriate counseling is recommended in this population. Additional research is warranted to identify risk factors and treatment strategies for these disorders.

Impulsivity and risk for mania: towards greater specificity.

BACKGROUND: Impulsivity is elevated among people diagnosed with bipolar disorder, and recent evidence suggests that impulsivity can predict onset among those at risk for the disorder. Impulsivity, though, is a broad construct. OBJECTIVE: The goal of this study was to examine whether some aspects of impulsivity are more correlated with risk for mania than others. We hypothesized that risk for mania would be related specifically to difficulties controlling impulsive responses to emotions. DESIGN AND METHODS: Undergraduates (N = 257) completed a large battery of measures of emotion-relevant and non-emotional forms of impulsivity, along with a well-validated measure of risk for mania, the Hypomanic Personality Scale (HPS). RESULTS: Analyses examined correlations of impulsivity scales with the HPS, and partial correlations controlling for lifetime tendencies towards depressive symptoms and current symptoms of alcohol abuse, both of which relate to impulsivity and often co-occur with mania. After controlling for these measures, risk for mania remained correlated with measures of impulsive responses to positive emotions, but not with difficulties in following through or with impulsivity in the context of general distress emotions. CONCLUSIONS: Although impulsivity is a major concern among those at risk for mania and those diagnosed with mania, difficulties may be especially evident during positive affective states, and other forms of impulsivity may be less related to mania risk. Discussion focuses on limitations and future directions. PRACTITIONER POINTS: Impulsivity is correlated with risk for mania. Mania risk appears tied to tendencies towards impulsive action, particularly during positive affective states. Mania risk was not significantly correlated with other non-emotional forms of impulsivity. A better understanding of what aspects of impulsivity are problematic in bipolar disorder could guide more refined interventions.

An intrinsic connectivity network approach to insula-derived dysfunctions among cocaine users.

BACKGROUND: Addiction is a complex phenotype, though it consistently includes characteristics of impulsivity. A number of brain regions are suggested to be involved in cocaine addiction, including the insula, which serves diverse functions including interoceptive awareness and integration of neural signals from sensory, subcortical and frontal regions. Malfunction of this integration links impulsive behavior to the insula. OBJECTIVES: This study examines intrinsic connectivity of the insula in chronic cocaine users to investigate abnormal insular circuitry, its role in cocaine addiction, and relationships to measure of impulsivity. METHODS: Cocaine-dependent individuals (n = 33) and healthy controls (n = 32) completed a resting-state fMRI scan. An intrinsic connectivity network (ICN) approach generated metrics of mean network connectivity and inter-network connectivity from fMRI data. Metrics pertaining to ICNs involving insula and other structures repeatedly involved in addiction (e.g. striatum) were selected for analysis, which included the capacity to discriminate groups. Relationships between group discriminating connectivity metrics and behavioral impulsivity were examined. RESULTS: Models demonstrated group prediction accuracy up to 75%. Accuracy of 69% was obtained by a parsimonious model of six inter-network connectivity metrics. The inter-network connectivity between an ICN involving the anterior insula and ACC, and an ICN involving the striatum, was significantly weaker in cocaine users relative to controls. The degree of reduced inter-network connectivity was significantly related to greater non-planning impulsivity in cocaine users. CONCLUSIONS: Aberrant insula-derived intrinsic connectivity patterns are observed in cocaine users and include dysfunctions in insula to striatal connectivity, which is furthermore linked to increased impulsivity pertaining to forethought.

Striatal-insula circuits in cocaine addiction: implications for impulsivity and relapse risk.

BACKGROUND: Dysregulated striatal functioning coupled with executive control deficits arising from abnormal frontal cortical function are considered key mechanisms in the development and maintenance of cocaine addiction. The same features are thought to underlie high trait impulsivity observed in cocaine-addicted populations. OBJECTIVES: Employing resting state functional connectivity, the current study sought to identify cortico-striatal circuit alterations in cocaine addiction and examine the degree to which circuit connectivity contributes to relapse risk and impulsivity among cocaine-addicted individuals. METHODS: Whole-brain resting-state functional magnetic resonance imaging connectivity was assessed in 45 cocaine-addicted individuals relative to 22 healthy controls using seed volumes in the left and right caudate, putamen and nucleus accumbens. Cocaine-addicted individuals completed scans in the final week of a 2-4 weeks residential treatment episode. Relapse by day 30 post-discharge served to separate cocaine-addicted individuals into relapse and non-relapse groups. All participants completed the Barratt Impulsivity Scale (BIS-11a). RESULTS: Cocaine-addicted individuals exhibited reduced positive connectivity between the bilateral putamen and posterior insula and right postcentral gyrus. Group differences were primarily driven by reduced connectivity in relapse individuals relative to controls. No relapse versus non-relapse differences emerged. Impulsivity (BIS-11a) was higher in cocaine-addicted participants, an effect that was partially mediated by reduced putamen-posterior insula connectivity in this group. CONCLUSION: Cocaine addiction, relapse risk and impulsivity were associated with reduced connectivity in putamen-posterior insula/postcentral gyrus circuits implicated in temporal discounting and habitual responding. Findings provide new insight into the neurobiological mechanisms underlying impulsivity and relapse in cocaine addiction.

Impulsivity, variation in the cannabinoid receptor (CNR1) and fatty acid amide hydrolase (FAAH) genes, and marijuana-related problems.

OBJECTIVE: Impulsivity is associated with increased marijuana use and subsequent marijuana-related problems among marijuana users. In addition, single nucleotide polymorphisms (SNPs) in the cannabinoid receptor 1 (CNR1) and fatty acid amide hydrolase (FAAH) genes have been associated with cannabis-related phenotypes. This exploratory study tested whether the association between different aspects of impulsivity and the number of marijuana-related problems among users is explicated by variation in these putative cannabinoid-related genes. METHOD: A total of 151 young adult regular marijuana users (used on M= 41.4% of the prior 60 days, SD = 24.3%) provided DNA and completed measures of trait (Barratt Impulsiveness Scale) and behavioral impulsivity (Stop Signal Task and Delay Discounting Questionnaire), as well as a self-report of marijuana-related problems. Three CNR1 and five FAAH SNPs were genotyped, tested for haplotype blocks, and subsequently examined for association with phenotypes described above. RESULTS: CNR1 variation significantly moderated the association between trait-level, but not behavioral, impulsivity and marijuana-related problems, such that the combination of higher trait impulsivity and CNR1 variation was associated with a greater number of marijuana-related problems. In contrast, there were no significant FAAH by impulsivity interactions; however, there was a main effect of FAAH on marijuana-related problems. CONCLUSIONS: These findings support an association with CNR1 and FAAH genes and marijuana-related problems among regular marijuana users. CNR1 variation emerged as a moderator of the relationship between trait impulsivity and marijuana problems, thus suggesting that marijuana users with CNR1 risk variants and a higher trait impulsivity are at greater risk for developing marijuana-related problems and supporting a role for CNR1 in a broader impulsivity phenotype.

The effects of alcohol problems and smoking on delay discounting in individuals with gambling problems.

Problem gambling is an addictive behavior with high comorbidity with alcohol problems and smoking. A common feature shared by these conditions is impulsivity. Past research shows that individuals with any of these addictions discount delayed money at higher rates than those without, and that the presence of gambling and substance use lead to additive effects on discounting. To date, however, no study examined the impact of smoking on these associations. The goals of this study were to compare the discounting rates of gamblers with and without histories of alcohol problems and smoking, and assess the associations these addictions might have on discounting. We analyzed the discounting rates of treatment-seeking gamblers categorized into four groups based on their histories of alcohol and smoking. Results revealed effects of history of alcohol problems, and an interaction between smoking and alcohol problems, on discounting. Never smokers with histories of alcohol problems discounted money less steeply than the other groups of gamblers. These results suggest that smoking does not produce additional increases on discounting rates in individuals with other addiction problems and the small subpopulation of gamblers with alcohol problems who never smoked is less impulsive and may have unique risk and/or protective behaviors.

The effects of ADHD in adult substance abusers.

The aim of this study was to evaluate the psychiatric comorbidities and different areas of life functioning in substance abusers with attention deficit hyperactivity disorder symptoms. A cross-sectional, multi-center study involving 285 adult substance abusers from outpatient and inpatient clinics was performed. The Adult ADHD Self-Report Scale, the sixth version of the Addiction Severity Index, and the Mini International Neuropsychiatry Interview were used for data collection. Individuals with comorbid attention deficit hyperactivity disorder and substance use disorders showed increased addiction severity when compared with individuals without attention deficit hyperactivity disorder (53.3 ± 7.3 vs. 48.4 ± 8.4, respectively). Our results suggest that comorbid attention deficit hyperactivity disorder and substance use disorders is associated with a more severe course of substance use and with social and psychiatric impairment.