Aggression and substance abuse in bipolar disorder

Objectives:  The goal of this retrospective study was to examine factors differentiating persons with bipolar disorder who did or did not have comorbid lifetime substance use disorders (SUD) at an index assessment. We also explored the chronology of onset of mood and SUD.
Methods:  We studied 146 subjects with DSM-defined bipolar disorder. Subgroups with and without lifetime SUD were compared on demographic and clinical measures.
Results:  Substance abuse disorders in this bipolar sample were associated with male sex, impulsive-aggressive traits, comorbid conduct and Cluster B personality disorders, number of suicide attempts and earlier age at onset of a first mood episode. In a multivariable logistic regression analysis, male sex and aggression and possibly earlier age at mood disorder onset were associated with SUD. In those with or without SUD, the first mood episode tended to be depressive and to precede the onset of SUD.
Conclusions:  In persons with bipolar disorder, an earlier age of onset and aggressive traits appear to be factors associated with later development of comorbid SUD.     

Predictors of punding in Parkinson's disease: results from a questionnaire survey.

Dopamine replacement therapy (DRT) for Parkinson's disease (PD) has recently been linked to the development of a number of nonmotor behavioral control problems. Punding, one of these nonmotor problems, is a term used to describe complex, purposeless stereotyped behaviors such as the repetitive handling or sorting of objects. A self-report questionnaire was adapted to assess punding in the context of dysfunctional hobby-related activities. We report the results of a survey of PD outpatients from a PD research clinic (n = 141) and non-PD controls (n = 103); conducted to identify clinical and psychological factors predictive of punding behaviors. The PD group reported hobbies and activities, which scored significantly higher on the Punding Scale than controls. Higher impulsivity, poorer disease-related quality of life, younger age of disease onset, and concomitant daily medication dosage from dopamine receptor agonists were independently predictive of higher Punding Scale scores in the PD group. These findings are similar to those seen in dopamine dysregulation syndrome, and provide further evidence for the role of impulsivity and age at disease onset in DRT-related nonmotor behavioral problems in PD.     

Anxiety,impulsivity and depressed mood in relation to suicidal and violent behavior

Many different variables have been associated with suicidal behavior as well as with violent behavior. This study was designed to test a model that attempts to relate such variables to violence and suicide risk. Sixty psychiatric patients were evaluated and divided into suicidal and nonsuicidal groups and then into violent and nonviolent groups. Scores on suicide risk, violence risk, anxiety, anger, impulsivity and mood were then compared between these groups. In a second analysis, scores on suicide risk and violence risk were correlated with all the other variables. Anxiety and impulsivity were found to strongly correlate with suicide risk. Angry and resentful mood correlated with violence risk; trait anxiety correlated negatively with violence risk. The results contribute further insight into the authors' two-stage model of countervailing forces.     

The Hunger Games: Homeostatic State-Dependent Fluctuations in Disinhibition Measured with a Novel Gamified Test Battery

Food homeostatic states (hunger and satiety) influence the cognitive systems regulating impulsive responses, but the direction and specific mechanisms involved in this effect remain elusive. We examined how fasting, and satiety, affect cognitive mechanisms underpinning disinhibition using a novel framework and a gamified test-battery. Thirty-four participants completed the test-battery measuring three cognitive facets of disinhibition: attentional control, information gathering and monitoring of feedback, across two experimental sessions: one after overnight fasting and another after a standardised meal. Homeostatic state was assessed using subjective self-reports and biological markers (i.e., blood-derived liver-expressed antimicrobial protein 2 (LEAP-2), insulin and leptin). We found that participants who experienced greater subjective hunger during the satiety session were more impulsive in the information gathering task; results were not confounded by changes in mood or anxiety. Homeostatic state did not significantly influence disinhibition mechanisms linked to attentional control or feedback monitoring. However, we found a significant interaction between homeostatic state and LEAP-2 on attentional control, with higher LEAP-2 associated with faster reaction times in the fasted condition only. Our findings indicate lingering hunger after eating increases impulsive behaviour via reduced information gathering. These findings identify a novel mechanism that may underpin the tendency to overeat and/or engage in broader impulsive behaviours.     

Association between Low-Activity Allele of Cathecolamine-O-Methyl-Transferase (COMT) and Borderline Personality Disorder in an Italian Population

The objective of the present study was to test the association between Borderline Personality Disorder (BPD) and the cathecolamine-O-methyl-transferase (COMT) low-activity (Met158) single nucleotide polymorphism (SNP). In this case-control study, DNA was obtained from venous blood of 19 BPD patients and 36 healthy subjects. COMT-Val158Met single-nucleotide polymorphism was genotyped by predesigned SNP assay. The COMT Met158 allele was over-represented in patients with BPD in comparison to normal subjects (68.4% vs 44.4%, respectively; Fisher exact test, p = .02). In terms of genotype, the Met158Met subjects were more frequent in patients versus controls (47.4% vs 22.2%, respectively), whereas the high-activity genotype Val158Val was under-represented (10.5% vs 33.3%, respectively). The allele encoding for the COMT with low enzymatic efficiency was found to be over-represented in BPD, possibly resulting in excessive synaptic dopaminergic activity and ultimately affecting externalizing behaviours, such as impulsivity and aggressiveness.     

Impulsive or Depressive Personality Traits Do Not Impede Behavioral Change After Brief Alcohol Interventions

ABSTRACT

The authors investigated whether impulsivity and depression affect the success of interventions to reduce alcohol use. Unadjusted and adjusted regression models were constructed to analyze the effect of impulsivity and depression on 12-month outcomes of participants of a trauma center based randomized trial of brief personalized motivational interventions versus information and advice. Of 497 problem drinkers enrolled in the program, 248 completed the 12-month follow-up. Impulsivity, male gender, being older than 35, and intentional mechanism of injury had a direct association with drinking. After interventions, a decrease in drinking was found that was unaffected by the presence of impulsivity or depression indicators.     

Delinquency and drug use among adolescents and emerging adults: The role of aggression,impulsivity, empathy,and cognitive distortions

Risk behaviors are well known to be higher in adolescents and emerging adults. Drug use and delinquency present several common predictive factors. The aim of the present study was to assess the contribution of individual factors (aggression, impulsivity, empathy, and cognitive distortions) to delinquent behaviors, alcohol use and cannabis consumption among adolescents and emerging adults. Participants were between 15 and 25 years of age (M = 18.64 years, SD = 2.61); 325 were adolescents (15–18 years of age, M = 16.56, SD = 1.11, 56.31% of women) and 283 were emerging adults (19–25 years, M = 21.03, SD = 1.62, 50.88% of women). They completed self-report validated questionnaires. Multiple regression analyses showed that all individual factors significantly predicted delinquency. Impulsivity and empathy significantly predicted alcohol use. Concerning cannabis use, impulsivity is the only significantly associated predictor. Moderation analysis showed that specific associations were stronger in adolescents, whereas others were stronger in emerging adults. All these variables explained 69% of the variance of delinquency, 31% of the variance of alcohol use, and 18% of the variance of cannabis use. This model demonstrated acceptable goodness-of-fit criteria. These results may have implications for prevention and intervention.     

Pharmacological treatments in pathological gambling

Pathological gambling (PG) is a relatively common and often disabling psychiatric condition characterized by intrusive urges to engage in deleterious gambling behaviour. Although common and financially devastating to individuals and families, there currently exist no formally approved pharmacotherapeutic interventions for this disorder. This review seeks to examine the history of medication treatments for PG. A systematic review of the 18 double-blind, placebo-controlled pharmacotherapy studies conducted for the treatment of pathological gambling was conducted. Study outcome and the mean dose of medication administered was documented in an effort to determine a preferred medication choice in this population. A variety of medication classes have been examined in the treatment of PG with varying results. Antidepressants, atypical antipsychotics and mood stabilizers have demonstrated mixed results in controlled clinical trials. Although limited information is available, opioid antagonists and glutamatergic agents have demonstrated efficacious outcomes, especially for individuals with PG suffering from intense urges to engage in the behaviour. Given that several studies have demonstrated their efficacy in treating the symptoms associated with PG, opioid antagonists should be considered the first line treatment for PG at this time. Most published studies, however, have employed relatively small sample sizes, are of limited duration and involve possibly non-representative clinical groups (e.g. those without co-occurring psychiatric disorders). Response measures have varied across studies. Heterogeneity of PG treatment samples may also complicate identification of effective treatments. Identification of factors related to treatment response will help inform future studies and advance treatment strategies for PG.     

Serotonin Platelet-Transporter Measures in Childhood Attention-Deficit/Hyperactivity Disorder (ADHD): Clinical versus Experimental Measures of Impulsivity

Summary: Impulsivity in terms of aggression, suicide or poor cognitive control has been associated with low synaptic availability of serotonin (5-HT) in adults and children. However, characteristics of the 5-HT transporter have not been studied in children with attention-deficit/hyperactivity disorder (ADHD: combined type), where impulsivity is a core symptom. Here, we explored in 20 children with ADHD the relationship of the density (Bmax) and affinity (Kd) of the platelet 5-HT transporter measured with [³H]paroxetine to both clinical ratings of impulsivity (Conners' Parent Questionnaire), and an experimental measure of impulsivity (the ability to withhold a prepotent response in the “stop-signal” paradigm). Decreases of affinity (increased Kd) correlated with a low probability of response inhibition, but not with the clinical ratings of impulsivity. However, ratings of distractibility and impulsivity correlated with the experimental measure of response-inhibition. In contrast, increased transporter affinity (low Kd) correlated modestly with higher ratings of aggressive and externalising behaviour. Bmax was not associated with any behavioural score. We conclude that the synaptic availability of 5-HT is under the control of the 5-HT transporter binding site affinity and that low affinity may be related to cognitive impulsivity (distractibility). Increased affinity of the transporter may also be related to conduct disturbance.