The role of outcome expectancy in therapeutic change across psychotherapy versus pharmacotherapy for depression.

BACKGROUND: Patient outcome expectancy - the belief that treatment will lead to an improvement in symptoms - is linked to favourable therapeutic outcomes in major depressive disorder (MDD). The present study extends this literature by investigating the temporal dynamics of expectancy, and by exploring whether expectancy during treatment is linked to differential outcomes across treatment modalities, for both optimistic versus pessimistic expectancy. METHODS: A total of 104 patients with MDD were randomized to receive either cognitive behavioral therapy (CBT) or pharmacotherapy for 16 weeks. Outcome expectancy was measured throughout treatment using the Depression Change Expectancy Scale (DCES). Depression severity was measured using both the Hamilton Depression Rating Scale and Beck Depression Inventory-II. RESULTS: Latent growth curve models supported improvement in expectancy across both treatments. Cross-lagged panel models revealed that both higher optimistic and lower pessimistic expectancy at mid-treatment predicted greater treatment response in pharmacotherapy. For CBT, the associative patterns between expectancy and depression differed as a function of expectancy type; higher optimistic expectancy at pre-treatment and lower pessimistic expectancy at mid-treatment predicted greater treatment response. LIMITATIONS: The sample size limited statistical power and the complexity of models that could be explored. CONCLUSIONS: Results suggest that outcome expectancy improved during treatment for depression. Whether outcome expectancy represents a specific mechanism for the reduction of depression warrants further investigation.

Cognitive change in cognitive-behavioural therapy v. pharmacotherapy for adult depression: a longitudinal mediation analysis.

BACKGROUND: Although cognitive-behavioural therapy (CBT) is a well-established treatment for adult depression, its efficacy and efficiency may be enhanced by better understanding its mechanism(s) of action. According to the theoretical model of CBT, symptom improvement occurs via reductions in maladaptive cognition. However, previous research has not established clear evidence for this cognitive mediation model. METHODS: The present study investigated the cognitive mediation model of CBT in the context of a randomized controlled trial of CBT v. antidepressant medication (ADM) for adult depression. Participants with major depressive disorder were randomized to receive 16 weeks of CBT (n = 54) or ADM (n = 50). Depression symptoms and three candidate cognitive mediators (dysfunctional attitudes, cognitive distortions and negative automatic thoughts) were assessed at week 0 (pre-treatment), week 4, week 8 and week 16 (post-treatment). Longitudinal associations between cognition and depression symptoms, and mediation of treatment outcome, were evaluated in structural equation models. RESULTS: Both CBT and ADM produced significant reductions in maladaptive cognition and depression symptoms. Cognitive content and depression symptoms were moderately correlated within measurement waves, but cross-lagged associations between the variables and indirect (i.e. mediated) treatment effects were non-significant. CONCLUSIONS: The results provide support for concurrent relationships between cognitive and symptom change, but not the longitudinal relationships hypothesized by the cognitive mediation model. Results may be indicative of an incongruence between the timing of measurement and the dynamics of cognitive and symptom change.

Parallel role for the dopamine D1 receptor in gambling and amphetamine reinforcement in healthy volunteers.

This study investigated the role of dopamine, and specifically the D1 receptor (D1R), in the reinforcing effects of a slot-machine game in healthy volunteers ( n=30). To compare gambling and drug effects, subjects received the prototypic psychostimulant drug d-amphetamine (AMPH; 20 mg) in a multi-session, placebo-controlled design. To isolate D1R, half the subjects were pretreated with the preferential D2 receptor antagonist haloperidol (HAL; 3 mg), and the other half with the mixed D1-D2 antagonist fluphenazine (FLU; 3 mg) before the game (Phase I) and AMPH (Phase II). HAL decreased and FLU increased the post-game desire to gamble and post-AMPH desire to take AMPH again, as well as amphetamine scale ratings on the Addiction Research Center Inventory after gambling and AMPH. The effects of the antagonists on desire to gamble and to take AMPH again were significantly intercorrelated. HAL increased and FLU decreased the salience of negative affective words on a rapid reading task after both reinforcers. HAL also decreased the salience of gambling words after AMPH. Both reinforcers increased diastolic blood pressure equally under antagonists and placebo. Results indicate that D1R plays a parallel role in the psychostimulant-like, incentive-motivational, and salience-enhancing effects of gambling and AMPH. Moderate D1R activation appears to optimize these effects in healthy subjects.

Strong interactions between learned helplessness and risky decision-making in a rat gambling model.

Risky decision-making is characteristic of depression and of addictive disorders, including pathological gambling. However it is not clear whether a propensity to risky choices predisposes to depressive symptoms or whether the converse is the case. Here we tested the hypothesis that rats showing risky decision-making in a rat gambling task (rGT) would be more prone to depressive-like behaviour in the learned helplessness (LH) model. Results showed that baseline rGT choice behaviour did not predict escape deficits in the LH protocol. In contrast, exposure to the LH protocol resulted in a significant increase in risky rGT choices on retest. Unexpectedly, control rats subjected only to escapable stress in the LH protocol showed a subsequent decrease in riskier rGT choices. Further analyses indicated that the LH protocol affected primarily rats with high baseline levels of risky choices and that among these it had opposite effects in rats exposed to LH-inducing stress compared to rats exposed only to the escape trials. Together these findings suggest that while baseline risky decision making may not predict LH behaviour it interacts strongly with LH conditions in modulating subsequent decision-making behaviour. The suggested possibility that stress controllability may be a key factor should be further investigated.

Childhood Abuse History in Depression Predicts Better Response to Antidepressants with Higher Serotonin Transporter Affinity: A Pilot Investigation.

OBJECTIVES: Childhood abuse is a powerful prognostic indicator in adults with major depressive disorder (MDD) and is associated with numerous biological risk factors for depression. The purpose of this investigation was to explore if antidepressant medication affinity for the serotonin transporter moderates the association between childhood abuse and treatment response. METHODS: Our sample included 52 outpatients with MDD who had received up to 26 weeks of pharmacotherapy, stratifying antidepressant medications with a high versus a low affinity for the serotonin transporter. Patients completed the Hamilton Rating Scale for Depression, Beck Depression Inventory II, Home Environment Questionnaire, and Ontario Health Supplement: Child Abuse and Trauma Scale to assess depression and childhood abuse. RESULTS: Medication class moderated the link between 3 indices of childhood abuse and treatment response such that higher levels of childhood abuse were associated with higher levels of depression severity after treatment only in those patients receiving antidepressant medications with a weak affinity for the serotonin transporter. CONCLUSIONS: This pilot study suggested that prolonged exposure to stress during childhood may result in biological vulnerabilities for depression, which may in turn be differentially targeted by pharmacological agents which target serotonin to a greater or lesser degree.

Differential cardiovascular and hypothalamic pituitary response to amphetamine in male pathological gamblers versus healthy controls.

Cardiovascular and hypothalamic pituitary axis (HPA) disturbances have been observed in individuals who are pathological gamblers (PGs). These may partly derive from chronic exposure to gambling. Response to amphetamine (AMPH) may reveal such disturbances while controlling for differential conditioned responses to gambling in PGs vs healthy controls (HCs). This study assessed heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) and plasma cortisol following oral AMPH (0.4 mg/kg) in male PGs (n=12) and HCs (n=11) who underwent a positron emission tomography (PET) scan. The Stop Signal Task enabled assessment of the link between physiological and behavioral dysregulation. Trait moderating effects were explored. The responses of PGs to AMPH differed from those of HCs on every index. PGs displayed persistent elevation in DBP and concomitant reduction in HR (i.e. baroreflex) compared to HCs beyond 90 min post-dose. PGs displayed deficits in cortisol compared to HCs that were partially reversed by AMPH. Impairment on the Stop Signal Task correlated positively with HR in controls, but negatively with HR in PGs, suggesting that strong initial and compensatory cardiac responses to a stimulant may each predict disinhibition. Extraversion predicted greater disinhibition in PGs. Noradrenergic disturbances may contribute to sensitized responses to stimulant challenge and disinhibition in PGs.

Deep brain stimulation of the subthalamic nucleus increases premature responding in a rat gambling task.

Deep brain stimulation of the subthalamic nucleus (STN-DBS) is a treatment option for the motor symptoms of Parkinson's disease (PD). However, several recent studies have found an association between STN-DBS and increased impulsivity. Currently, it is not clear whether the observed increase in impulsivity results from STN-DBS per se, or whether it involves an interaction with the underlying PD neuropathology and/or intake of dopaminergic drugs. We investigated the effects of STN-DBS on performance of intact rats on two tasks measuring impulsive responding: a novel rat gambling task (rGT) and a differential reinforcement of low rate responding (DRL20s) schedule. Following initial behavioural training, animals received electrode implantation into the STN (n=24) or sham surgery (n=24), and were re-tested on their assigned behavioural task, with or without STN-DBS. Bilateral STN-DBS administered for two hours immediately prior to testing, had no effects on rGT choice behaviour or on DRL response inhibition (p>0.05). However, STN-DBS significantly increased premature responding in the rGT task (p=0.0004), an effect that took several sessions to develop and persisted in subsequent trials when no stimulation was given. Consistent with the notion of distinct facets of impulsivity with unique neurochemical underpinnings, we observed differential effects of STN-DBS in the two tasks employed. These results suggest that STN-DBS in the absence of parkinsonism may not lead to a general loss of inhibitory control, but may instead affect impulsivity under specific conditions.

The role of ANKK1 and TTC12 genes on drinking behaviour in tobacco dependent subjects.

OBJECTIVES: Alcohol use disorders (AUD) act as a risk factor for smoking relapse, and tobacco dependent (TD) subjects with comorbid AUD experience more withdrawal symptoms compared to TD subjects without AUD or other psychiatric comorbidities. Our aim was to investigate whether drinking behaviour in the past 12 months and smoking relapse due to alcohol use in TD subjects was associated with polymorphisms flanking the TTC12/ANKK1/DRD2 region since associations have been found between these genes and AUD and TD as separate disorders. METHODS: 380 TD subjects were assessed for alcohol use and relapse to smoking. Subjects were genotyped for polymorphisms located in the TTC12/ANKK1/DRD2 region. RESULTS: Associations were found between ANKK1 haplotype rs4938015C_rs11604671A and age of onset of daily smoking, as well as with hazardous drinking. No genetic association was found with smoking relapse due to alcohol consumption. CONCLUSIONS: Our findings suggest that TD subjects who present earlier age at onset and carry this haplotype may have a higher risk for developing an alcohol use disorder.

Association of functional variants in the dopamine D2-like receptors with risk for gambling behaviour in healthy Caucasian subjects.

Pathological gambling (PG) is an impulse control disorder with suggestive genetic vulnerability component. We evaluated the association of genetic variants in the dopaminergic receptor genes (DRD1-3s) with risk for gambling in healthy subjects using the Canadian Problem Gambling Index (CPGI). Healthy Caucasian subjects who had gambled at least once in their lifetime (n=242) were included in the analysis. Gender was not associated with the CPGI, while younger age was associated with higher CPGI scores. We have found that none of the single polymorphisms investigated on DRD1 and DRD3 were associated with CPGI scores in healthy subjects. However, we observed trends for association on the TaqIA/rs1800497 polymorphism (P=0.10) and the haplotype flanking DRD2 (G/C/A rs11604671/rs4938015/rs2303380; P=0.06). Both trends were associated with lower CPGI score. Our results provide further evidence for the role of dopamine D2-like receptor in addiction susceptibility.

Cocaine and amphetamine regulated transcript (CART) gene in the comorbidity of schizophrenia with alcohol use disorders and nicotine dependence.

Studies have shown a genetic susceptibility to develop schizophrenia, alcohol use disorders and nicotine dependence. Brain areas related to reward and reinforcement show high expression of the cocaine and amphetamine regulated transcript (CART). Nicotine and alcohol are also able to modulate CART expression in the hypothalamic areas. In this study, we evaluated whether CART variants would influence the predisposition of schizophrenia subjects to alcohol use disorders and nicotine dependence. Clinical and genetic data were obtained from 190 unrelated Caucasian schizophrenia subjects collected at the Centre for Addiction and Mental Health. We found no association of CART variants with alcohol use disorders or nicotine dependence. We found a trend for allelic association of rs11575893 with the heaviness of smoking behaviour (p=0.057). Our results indicate that genetic variants in the CART gene may not play a major role in the vulnerability of schizophrenia subjects to concurrent alcohol use disorders and nicotine dependence. Additional association studies in independent samples can evaluate whether CART gene is playing a role in the schizophrenia comorbidity with alcohol use disorders and nicotine dependence.

Genetic aspects of pathological gambling: a complex disorder with shared genetic vulnerabilities.

AIMS: To summarize and discuss findings from genetic studies conducted on pathological gambling (PG). METHODS: Searches were conducted on PubMed and PsychInfo databases using the keywords: 'gambling and genes', 'gambling and family' and 'gambling and genetics', yielding 18 original research articles investigating the genetics of PG. RESULTS: Twin studies using the Vietnam Era Twin Registry have found that: (i) the heritability of PG is estimated to be 50-60%; (ii) PG and subclinical PG are a continuum of the same disorder; (iii) PG shares genetic vulnerability factors with antisocial behaviours, alcohol dependence and major depressive disorder; (iv) genetic factors underlie the association between exposure to traumatic life-events and PG. Molecular genetic investigations on PG are at an early stage and published studies have reported associations with genes involved in the brain's reward and impulse control systems. CONCLUSIONS: Despite the paucity of studies in this area, published studies have provided considerable evidence of the influence of genetic factors on PG and its complex interaction with other psychiatric disorders and environmental factors. The next step would be to investigate the association and interaction of these variables in larger molecular genetic studies with subphenotypes that underlie PG. Results from family and genetic investigations corroborate further the importance of understanding the biological underpinnings of PG in the development of more specific treatment and prevention strategies.

The genetics of gambling and behavioral addictions.

Behavioral addictions are considered as the repetitive occurrence of impulsive behaviors without consideration of their potential negative consequences. These addictions represent an increasing cost to society and are an important new field of research in psychiatric genetics. There has been a growing body of evidence on the familial aggregation and genetic influences on the development of behavioral addictions and mainly on pathological gambling. The aim of this article is to critically review findings of family and molecular genetic studies on behavioral addictions, focusing on pathological gambling and commenting on other disorders where appropriate. This review provides a comprehensive approach to genetic studies on behavioral addiction and points out the necessity of expanding the genetic research in this field. Future directions for genetic studies in this field are also discussed.

Factors at play in faster progression for female pathological gamblers: an exploratory analysis.

BACKGROUND: Previous studies reported a faster progression for alcohol dependence and pathological gambling among females as compared with males. This phenomenon was called the "telescoping effect." By comparing female gamblers with male gamblers regarding gambling preferences and comorbidity, the authors explored potential risk factors for telescoping. METHOD: A consecutive sample of Brazilian treatment-seeking pathological gamblers (DSM-IV criteria) was recruited. Genders were contrasted regarding comorbidity and gambling behavior, controlling for demographics, gambling severity, and previous access to mental health services. RESULTS: Seventy female gamblers and 70 male gamblers were interviewed. A greater proportion of women than men reported electronic bingo and video lottery terminals as their main type of gambling. Gambling was divided in 3 progressive stages: "social gambling," "intense gambling," and "problem gambling." Faster progression for female gamblers was confirmed; female gender and preference for electronic bingo and/or video lottery terminals were risk factors for telescoping throughout all stages. Female gamblers presented a higher comorbidity with depression, whereas male gamblers had higher rates of alcohol dependence. Nevertheless, comorbidity profiles were not related to gambling progression. CONCLUSION: Two factors could be at play for treatment-seeking female gamblers in Brazil: (1) a potential gender vulnerability and (2) a cultural environment yielding them access to a narrower range of gambling games that includes mainly the most addictive ones.

Pathological gambling in women: a review.

Pathological gambling was only recently recognized as a psychiatric disorder (DSM-III, APA, 1980). Most studies of pathological gambling include only male subjects. Despite the paucity of information, it is likely that at least one-third of pathological gamblers are women. The objective of this article is to review clinical and epidemiological characteristics of female gamblers as compared to their male counterparts. MEDLINE and PsycINFO were searched for investigational studies and reviews of the past 10 years on clinical (sociodemographic, course and progression, psychiatric comorbidities, genetics, and personality) and epidemiological aspects of female gamblers. Other relevant articles were also selected from reference lists. It is concluded that the current literature indicates some common characteristics in female and male gamblers, but it also indicates the possibility that each gender may carry etiopathogenic differences that when better understood should lead to improved treatment and prevention strategies.

Pathological gambling in women: a review

Pathological gambling was only recently recognized as a psychiatric disorder (DSM-III, APA, 1980). Most studies of pathological gambling include only male subjects. Despite the paucity of information, it is likely that at least one-third of pathological gamblers are women. The objective of this article is to review clinical and epidemiological characteristics of female gamblers as compared to their male counterparts. MEDLINE and PsycINFO were searched for investigational studies and reviews of the past 10 years on clinical (sociodemographic, course and progression, psychiatric comorbidities, genetics, and personality) and epidemiological aspects of female gamblers. Other relevant articles were also selected from reference lists. It is concluded that the current literature indicates some common characteristics in female and male gamblers, but it also indicates the possibility that each gender may carry etiopathogenic differences that when better understood should lead to improved treatment and prevention strategies