Serotonin transporter gene (5-HTT) polymorphisms and compulsive buying

Coping associated with compulsive buying tendency

Research on general coping is limited within compulsive buying (CB) literature. Nevertheless, other behavioural addictions and hoarding might provide insights into coping in CB. One-hundred and ninety-nine participants (M age = 52.72, SD = 16.06; 50.3% female, 1% unknown sex) completed online questionnaires. Mental and behavioural disengagements were hypothesized to predict greater self-reported CB tendency. Whilst these relationships were found in the correlations, a regression analysis indicated that only mental disengagement significantly predicted CB tendency. Additionally, the exploration of denial and substance use identified that denial was an important predictor of CB tendency coping. The relationship between CB tendency and substance use could not be explored given the large degree of participants reporting minimal scores. CB tendency is associated with maladaptive mental disengagement, denial and lack of acceptance coping strategies, which could be useful to consider in therapy.

A Review of Pharmacologic Treatment for Compulsive Buying Disorder

At present, no treatment recommendations can be made for compulsive buying disorder. Recent studies have found evidence for the efficacy of psychotherapeutic options, but less is known regarding the best pharmacologic treatment. The purpose of this review is to present and analyze the available published evidence on the pharmacological treatment of compulsive buying disorder. To achieve this, we conducted a review of studies focusing on the pharmacological treatment of compulsive buying by searching the PubMed/MEDLINE database. Selection criteria were applied, and 21 studies were identified. Pharmacological classes reported included antidepressants, mood stabilizers, opioid antagonists, second-generation antipsychotics, and N-methyl-D-aspartate receptor antagonists. We found only placebo-controlled trials for fluvoxamine; none showed effectiveness against placebo. Three open-label trials reported clinical improvement with citalopram; one was followed by a double-blind discontinuation. Escitalopram was effective in an open-label trial but did not show efficacy in the double-blind phase. Memantine was identified as effective in a pilot open-label study. Fluoxetine, bupropion, nortriptyline, clomipramine, topiramate and naltrexone were only reported to be effective in clinical cases. According to the available literature, there is no evidence to propose a specific pharmacologic agent for compulsive buying disorder. Future research is required for a better understanding of both pathogenesis and treatment of this disorder.

A targeted review of the neurobiology and genetics of behavioural addictions: an emerging area of research

This review summarizes neurobiological and genetic findings in behavioural addictions, draws parallels with findings pertaining to substance use disorders, and offers suggestions for future research. Articles concerning brain function, neurotransmitter activity, and family history and (or) genetic findings for behavioural addictions involving gambling, Internet use, video game playing, shopping, kleptomania, and sexual activity were reviewed. Behavioural addictions involve dysfunction in several brain regions, particularly the frontal cortex and striatum. Findings from imaging studies incorporating cognitive tasks have arguably been more consistent than cue-induction studies. Early results suggest white and grey matter differences. Neurochemical findings suggest roles for dopaminergic and serotonergic systems, but results from clinical trials seem more equivocal. While limited, family history and genetic data support heritability for pathological gambling and that people with behavioural addictions are more likely to have a close family member with some form of psychopathology. Parallels exist between neurobiological and genetic and family history findings in substance and nonsubstance addictions, suggesting that compulsive engagement in these behaviours may constitute addictions. To date, findings are limited, particularly for shopping, kleptomania, and sexual behaviour. Genetic understandings are at an early stage. Future research directions are offered.

Impulse control disorders in Parkinson's disease: seeking a roadmap toward a better understanding

The development of an impulse control disorder (ICD) is now recognized as a potential nonmotor adverse effect of dopamine replacement therapy in Parkinson's disease (PD). Here, recent epidemiological, neurophysiological and genetic advances are summarized to outline potential mechanisms involved. It is safe to say that dopaminergic drugs, particularly dopamine agonists, are able to induce ICDs only in a minority of patients, while the majority are somehow protected from this adverse effect. While it seems clear that men with early-onset PD are more vulnerable, other predisposing factors, such as various current or pre-PD personality traits, are a matter of debate. In terms of neurophysiological advances, one may find striking analogies to the addiction literature suggesting a causal chain beginning with certain predisposing conditions of striatal dopamine synapses, an "unnatural" increase of dopamine stimulation and a characteristic pattern of resulting functional changes in remote networks of appetitive drive and impulse control. Future prospects include potential add-on medications and the possible identification of genetic predispositions at a genome-wide scale. Functional imaging of pharmacogenetic interactions (imaging pharmacogenomics) may be an important tool on that road.

Polymorphisms in the 3' UTR of the serotonin transporter are associated with cognitive flexibility in rhesus macaques

The serotonin system is an important neurophysiological mediator of many behavioral phenotypes. Genetic variation within this system is thought to contribute not only to the natural range of behavioral differences, but also to neuropsychiatric pathologies. Cognitive flexibility, the ability to change patterns of response as reward context shifts, is an important trait that underlies many complex social interactions. Environmental manipulations of the serotonin system have been shown to alter performance on tests measuring cognitive flexibility. Variation at the serotonin transporter promoter region (5HTTLPR) has recently been shown to associate with the performance of rhesus monkeys on an object discrimination reversal learning task [Izquierdo et al., 2007]. Here, we demonstrate that functional genetic variation at the serotonin transporter 3' untranslated region, independent of 5HTTLPR, also associates with performance in an object discrimination reversal learning task in rhesus macaques. The polymorphisms comprising the T:G:T haplotype (T1970, G1991, and T2327) were associated with fewer errors on a reversal learning test and greater levels of cognitive flexibility. We have previously demonstrated that the T:G:T haplotype renders lower levels of gene expression in vitro, paralleling the functionality of human 3' UTR haplotypes, as well as the short allele of 5HTTLPR found in both macaques and humans. The 3' UTR haplotypes are independent and in linkage equilibrium with the 5HTTLPR locus. Together, these data lead to the intriguing possibility that differences observed in human cognitive flexibility, whether naturally or in pathological states, may be associated with genetic variation in the serotonin transporter 3' untranslated region also.

Impulsive-compulsive buying disorder: clinical overview

Impulsive-compulsive buying disorder (ICBD) is an impulse control disorder not otherwise specified (ICD-NOS) characterized by impulsive drives and compulsive behaviours (buying unneeded things), personal distress, impaired social and vocational functioning and financial problems. Despite being described in the 19th century, serious attention to ICBD began only in the last decade with the first epidemiological and pharmacological investigation. Biological, social and psychological factors contribute to the aetiology of ICBD. Cognitive-behavioural therapy and selective serotonin re-uptake inhibitors are currently considered the more effective interventions in the treatment of ICBD. The present review aims to provide a broad overview of the epidemiology, aetiology, phenomenology and treatment options of ICBD.

Compras compulsivas: uma revisão e um relato de caso

OBJETIVO: O transtorno do comprar compulsivo foi descrito pela primeira vez como uma síndrome psiquiátrica no começo do século XX. Sua classificação permanece incerta e os investigadores têm debatido uma correlação potencial com transtornos do humor, transtorno obsessivo-compulsivo e transtornos do impulso. O objetivo deste estudo é apresentar uma revisão de transtorno do comprar compulsivo e um relato de caso. MÉTODO: Duas bases de dados foram investigadas (Medline e PsycINFO) em busca de artigos publicados nos últimos 40 anos. Os unitermos selecionados foram "oniomania" e "compras compulsivas". Outros artigos relevantes também foram identificados por meio das listas de referências. RESULTADOS: O transtorno do comprar compulsivo é uma condição crônica e prevalente encontrada ao redor do mundo, que divide características comuns com transtornos do controle do impulso. Em amostras clínicas, mulheres perfazem mais de 80% dos sujeitos. Sua etiologia é desconhecida, mas mecanismos neurobiológicos e genéticos têm sido propostos. O transtorno apresenta altas taxas de comorbidade com transtornos do humor, abuso de substâncias, transtornos alimentares e transtornos do controle do impulso. CONCLUSÃO: As recomendações terapêuticas derivadas da literatura e da experiência clínica sugerem que compradores compulsivos podem se beneficiar de intervenções psicossociais. Modelos de intervenção cognitivo-comportamental de grupo parecem promissores. Ensaios farmacológicos relatam resultados conflitantes. A identificação e o tratamento das comorbidades psiquiátricas são também um aspecto chave do tratamento. Para determinar a validade do transtorno do comprar compulsivo, os futuros trabalhos devem enfocar os achados psicopatológicos e neurobiológicos específicos à síndrome.

The neurobiology and genetics of impulse control disorders: relationships to drug addictions

Impulse control disorders (ICDs), including pathological gambling, trichotillomania, kleptomania and others, have been conceptualized to lie along an impulsive-compulsive spectrum. Recent data have suggested that these disorders may be considered addictions. Here, we review the genetic and neuropathological bases of the impulse control disorders and consider the disorders within these non-mutually exclusive frameworks.

Compulsive buying disorder: a review of the evidence

Compulsive buying disorder is characterized by excessive or poorly controlled preoccupations, urges, or behaviors regarding shopping and spending that lead to subjective distress or impaired functioning. Compulsive buying disorder is estimated to have a lifetime prevalence of 5.8% in the United States general adult population. In clinical settings, most individuals with compulsive buying disorder are women (approximately 80%). This gender difference may be artifactual. Compulsive buying disorder is typically chronic or intermittent, with an age of onset in the late teens or early 20s. Comorbid mood and anxiety disorders, substance use disorders, eating disorders, and other disorders of impulse control are common, as are Axis II disorders. The disorder occurs worldwide, mainly in developed countries with market-based economies, and it tends to run in families with mood disorders and substance abuse. There is no standard treatment for compulsive buying disorder, but group cognitive-behavioral models seem promising, and psychopharmacologic treatments are being actively studied. Other treatment options include simplicity circles, 12-step programs, financial counseling, bibliotherapy, marital therapy, and financial counseling. Directions for future research are discussed.

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.

Validity of PCR with emphasis on variable number of tandem repeat analysis

OBJECTIVES

Variable number of tandem repeat polymorphisms (VNTR) are frequently analyzed by PCR in genetic, epidemiologic and forensic studies. We wanted to explore the validity of these PCR analyses.

DESIGN AND METHODS

The amplification of the different alleles of the 17- and the 44-bp VNTR of the serotonin transporter gene and the 39-bp VNTR of the glycoprotein Ibalpha gene was analyzed. We studied the effects of the parameters magnesium, dimethylsulfoxide, 7-deaza-dGTP, formamide, betaine, PCR temperatures and different types of polymerases.

RESULTS

In all three VNTR polymorphisms selective amplification of one of the alleles of heterozygous individuals could be obtained by change of the magnesium concentration. This problem could be minimized by a combination of Taq- and Pwo-polymerases and by use of 7-deaza-dGTP.

CONCLUSION

PCR analysis of all of these VNTRs may give reproducibly wrong results in truly heterozygous subjects due to selective amplification of only one of the alleles.

Compulsive buying disorder: definition, assessment, epidemiology and clinical management

Compulsive buying disorder is characterised by excessive or poorly controlled preoccupations, urges or behaviours regarding shopping and spending, which lead to adverse consequences. Compulsive buying disorder has been estimated to affect from 2 to 8% of the general adult population in the US; 80 to 95% of those affected are female. Onset occurs in the late teens or early twenties, and the disorder is generally chronic. Psychiatric comorbidity is frequent, particularly mood, anxiety, substance use, eating and personality disorders. Treatment has not been well delineated, but individual and group psychotherapy, cognitive-behavioural therapy and 12-step programmes may be helpful. Debt consolidation and credit counselling will be appropriate for many individuals who have compulsive buying disorder. Serotonin (5-hydroxytryptamine; 5-HT) re- uptake inhibitors may help some patients regulate their buying impulses. Self-help books are also available.

Personality and polymorphisms of genes involved in aminergic neurotransmission

Genetic factors significantly contribute to the determination of human personality traits assessed by self-report questionnaires. However, only in the past few years have common genetic polymorphisms especially the dopamine D4 receptor and the serotonin transporter promoter region been associated with specific personality traits such as novelty seeking and harm avoidance, respectively. The effects of these genes are modest and several genes are likely accounting for individual differences in personality dimensions that can be attributed to genetic factors. Molecular genetic studies of adult personality have also been extended to investigations of early human temperament and some of the genes associated with adult personality traits are also contributing to the earliest developmental expressions of human behavior. Additionally, some of these same genes have also been implicated in various types of abnormal behavior including addiction, obsessive-compulsive disorder, attention deficit, depression, aggression and psychosis. Future research directions will no doubt take advantage of the bioinformatics revolution coinciding with the completion of the first phase of the human genome project. It should soon be possible to identify many of the genes contributing to specific personality traits and to better define their role in determining normal and abnormal behavior from early development through adulthood.