Psychopathy traits in adolescents with childhood attention-deficit hyperactivity disorder

Examining Narcissistic Traits in Relation To Reactive and Proactive Aggression in Children At-Risk for Attention Deficit/Hyperactivity Disorder

The current study examined narcissistic traits in relation to proactive and reactive functions of aggression in a sample of children at-risk for attention-deficit/hyperactivity disorder (ADHD). Children ages 7-13 years (N = 110) were recruited from a pediatric ADHD assessment clinic. Caregivers completed the Antisocial Process Screening Device. Caregivers and teachers completed a measure of proactive and reactive aggression. In regression analyses controlling for ADHD and oppositional defiant disorder symptom severity and sex, narcissism was uniquely associated with higher caregiver-reported proactive aggression but not reactive aggression. Findings suggest that narcissism is uniquely related to proactive aggression in children at-risk for ADHD. Consideration of narcissistic traits may aid the prediction of behavioral issues and aggression in children and may be a potential intervention target. Future research should investigate if clinical interventions addressing narcissistic behaviors are effective for reducing proactive aggression in children.

Why Do They Do It? The Psychology Behind Antisocial Behavior in Children and Adolescents

Antisocial Personality Disorder (ASPD) is a complex and often debilitating condition that can emerge from early behavioral disturbances in childhood and adolescence. This narrative review provides a comprehensive overview of the current understanding of ASPD in pediatric and adolescent populations, examining key diagnostic challenges, developmental trajectories, and emerging treatment approaches. Recent research underscores the critical role of the early identification of conduct disorder (CD) and oppositional defiant disorder (ODD) as precursors to ASPD. Specific attention is given to biological, environmental, and psychosocial risk factors, including genetic predispositions, family dynamics, and socio-economic adversity. Additionally, neuro-psychological research highlights deficits in executive function, emotion regulation, and social cognition, which may underline the persistent antisocial patterns. Neuroimaging studies suggest atypical neural activity in regions associated with empathy, reward processing, and impulse control. Effective intervention remains a challenge, as treatment options are limited and often complicated by co-occurring conditions, such as attention deficit hyperactivity disorder (ADHD) and mood disorders. Promising evidence supports the efficacy of integrative, multimodal approaches combining behavioral therapy, family interventions, and pharmacotherapy to reduce symptom severity and improve long-term outcomes. The review concludes by advocating for a public health approach that emphasizes prevention and early intervention, aiming to mitigate the progression to full ASPD in adulthood.

The effect of a single dose of methylphenidate on attention in children and adolescents with ADHD and comorbid Oppositional Defiant Disorder

The co-occurrence Oppositional Defiant Disorder (ODD) in children and adolescents with Attention Deficit Hyperactivity Disorder (ADHD) has been associated to difficulties in regulating adverse states, elevated functional impairment, deficits in Executive Functions and high risk for psychopathology. Recent studies have shown that ODD is a negative predictor of a positive response to methylphenidate (MPH) treatment for ADHD symptoms in children and adolescents and that patients with a diagnosis of comorbid ADHD and ODD are less likely to respond favorably to pharmacological treatment with MPH. We conducted a naturalistic study to understand the clinical characteristics of drug-naïve children and adolescents with ADHD that influence the response to MPH by measuring the effect on attention. Specifically, we investigated whether a single dose of MPH differently affects the performance of 53 children and adolescents with ADHD with or without ODD comorbidity. In addition, participant characteristics such as symptom severity, functional impairment, and associated behavioral and emotional symptoms at baseline were examined to better understand what aspects affect the response to MPH. We found that a single dose of MPH improved the attention of children and adolescents with ADHD without ODD more than those with comorbid ADHD and ODD, resulting in reduced reaction times. Our findings indicated that children and adolescents with comorbid ADHD and ODD and those with ADHD alone did not exhibit differences in measures of attention prior to taking MPH, nor in demographic variables (age, intelligence quotient, gender), clinical characteristics related to symptom severity, and adaptive behaviors. However, we observed differences between the two groups in certain behavioral aspects, including the Dysregulation Profile and disruptive behaviors. Assessing symptoms in combination with the presence of ADHD can be beneficial in determining which individuals would derive the greatest benefits from treatment.

ADHD Among Offenders: Prevalence and Relationship With Psychopathic Traits

Objective: Longitudinal studies have shown a strong association between ADHD and criminal behavior. The aims of this study were to examine the prevalence of adult ADHD in a high-security facility and to investigate the relationship between ADHD symptoms and psychopathic traits in criminal offenders. Material and Methods: Participants were recruited between October 2015 and January 2016 among the inmates from a high-security all-male correctional facility in Portugal. Self-report scales were used to measure ADHD symptoms, current psychopathology, and psychopathic traits. An interview was conducted to collect sociodemographic data, along with information about adverse childhood experiences, substance use, and criminal record. The statistical analysis was conducted using STATA 13 with the significance level set at .05. Results: From the final sample of 101 male prisoners, 17 participants (16.8%) screened positive for ADHD. Participants positive for ADHD had higher levels of general psychopathology and psychopathic traits. Psychopathic traits remained significantly higher in ADHD offenders after controlling for age, substance abuse, and early childhood adversities (OR = 1.07, p = .002) and this was explained by differences in the Meanness subscale (OR = 1.11, p = .013). Discussion/conclusions: The present study shows that ADHD symptoms are highly prevalent among offenders and might have a modulating effect on the course of delinquent behavior. The cross-sectional association between ADHD symptoms and psychopathic traits reinforces the previously documented correlation between these disorders and can lead to a better understanding of the prevalent criminal behavior in ADHD patients.

Attention-Deficit/Hyperactivity Disorder (ADHD), antisociality and delinquent behavior over the lifespan

Attention-Deficit/Hyperactivity Disorder (ADHD) is closely linked to the development of conduct problems during socialization in early life and to an increased risk for antisocial activities and delinquency over the lifespan. The interaction between ADHD and common comorbid disorders like substance use disorders as well as changing environmental conditions could mediate the course of antisocial and delinquent behavior with increasing age. However, this complex interaction is only partially understood so far. This review presents current knowledge about the association of ADHD with antisociality and the development of delinquent behavior. Thereby, the relationships between ADHD, conduct disorder and antisocial personality disorder in offenders are discussed, as well as the impact of comorbid psychiatric disorders and psychosocial conditions on offending behavior. Also, treatment studies in offender populations with ADHD are presented. Although our understanding of the role of ADHD in the development of criminal behavior has substantially improved during the last two decades, more research is needed to further elucidate the mechanisms generating unfavorable outcomes and to engender adequate treatment strategies for this population at risk. Moreover, more attention is needed on children with conduct problems in order to avoid antisocial or delinquent behaviors over the lifespan.

Genome-Wide DNA Methylation Patterns in Persistent Attention-Deficit/Hyperactivity Disorder and in Association With Impulsive and Callous Traits

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that often persists into adulthood. ADHD and related personality traits, such as impulsivity and callousness, are caused by genetic and environmental factors and their interplay. Epigenetic modifications of DNA, including methylation, are thought to mediate between such factors and behavior and may behave as biomarkers for disorders. Here, we set out to study DNA methylation in persistent ADHD and related traits. We performed epigenome-wide association studies (EWASs) on peripheral whole blood from participants in the NeuroIMAGE study (age range 12-23 years). We compared participants with persistent ADHD (n = 35) with healthy controls (n = 19) and with participants with remittent ADHD (n = 19). Additionally, we performed EWASs of impulsive and callous traits derived from the Conners Parent Rating Scale and the Callous-Unemotional Inventory, respectively, across all participants. For every EWAS, the linear regression model analyzed included covariates for age, sex, smoking scores, and surrogate variables reflecting blood cell type composition and genetic background. We observed no epigenome-wide significant differences in single CpG site methylation between participants with persistent ADHD and healthy controls or participants with remittent ADHD. However, epigenome-wide analysis of differentially methylated regions provided significant findings showing that hypermethylated regions in the APOB and LPAR5 genes were associated with ADHD persistence compared to ADHD remittance (p = 1.68 * 10-24 and p = 9.06 * 10-7, respectively); both genes are involved in cholesterol signaling. Both findings appeared to be linked to genetic variation in cis. We found neither significant epigenome-wide single CpG sites nor regions associated with impulsive and callous traits; the top-hits from these analyses were annotated to genes involved in neurotransmitter release and the regulation of the biological clock. No link to genetic variation was observed for these findings, which thus might reflect environmental influences. In conclusion, in this pilot study with a small sample size, we observed several DNA-methylation-disorder/trait associations of potential significance for ADHD and the related behavioral traits. Although we do not wish to draw conclusions before replication in larger, independent samples, cholesterol signaling and metabolism may be of relevance for the onset and/or persistence of ADHD.

Callous-unemotional traits and the attentional bias towards emotional stimuli: Testing the moderating role of emotional and behavioural problems among high-risk adolescents

Former studies demonstrated that antisocial youth with callous-unemotional (CU) traits are impaired in the processing of negative emotional stimuli. The aim of the current study was to explore the moderating role of different behavioural (i.e. conduct problems, hyperactivity-inattention) and emotional problems (i.e. internalizing symptoms) in the relationship between CU traits and attentional bias towards emotional stimuli. Besides using self-report measures, attentional bias was tested by an affective dot-probe task in a high-risk sample of 102 adolescent boys (M age = 16.34 years; SD = 1.32). CU traits were related to reduced attention to emotionally distressing pictures. Furthermore, conduct problems significantly moderated the relationship between CU traits and attention to distress cues. These findings highlight the importance of considering potential moderators to the well-established link between CU traits and deficits in response to negative emotional cues.

The effect of methylphenidate treatment on psychopathic behavior of patients having attention-deficit hyperactivity disorder with and without oppositional defiant disorder

To evaluate the effect of 3 months of methylphenidate (MPH) treatment on psychopathic behavior in children having attention-deficit hyperactivity disorder (ADHD) with and without comorbid oppositional defiant disorder (ODD). Twenty-seven children with Diagnostic and Statistical Manual of Mental Disorders, fifth ed., ADHD (13 female/14 male; aged 13.3±2.2 years old) were compared to an age/sex matched ADHD/ODD group (N=27, eight female/19 male; aged 11.8±1.9 years). The attention-deficit hyperactivity disorder rating scale (ADHD-RS) and the California Child Q-Set (CCQ) were used in both groups before MPH treatment (0.8-1.2 mg/kg/day) and 3 months thereafter. Significant reduction in the ADHD-RS scores was detected following MPH treatment in both the ADHD/ODD group and in the ADHD group (P<0.0011 and P=0.0012, respectively). Reduction in the CCQ scores was obtained in the ADHD/ODD group (P=0.0001) but not in in the ADHD group (P=0.18). A correlation was found between the reductions in the ADHD-RS and CCQ scores following MPH treatment in the ADHD/ODD group (Spearman's r=0.43, P=0.024). MPH treatment in children with ADHD/ODD was associated with reduction in psychopathic scores, and the reduction correlated with a corresponding improvement in their ADHD severity.

The Development of Severe and Chronic Violence Among Youth: The Role of Psychopathic Traits and Reward Processing

Psychopathic traits are a manifestation of a personality pathology that comprises a core affective-interpersonal dysfunction (callous-unemotional traits) and an impulsive-antisocial behavioral component. Of particular importance, psychopathic traits are associated with the perpetration of some of the most severe acts of violence, and they appear to indicate a subset of youth at risk for earlier onset, greater frequency, and persistence of violent offending. Although these youth represent a minority of the population, they commit a significant proportion of the violence in the general community. In our review, we highlight evidence of a unique neurobiological predisposition that underlies the core affective deficits and describe contemporary accounts for the developmental processes leading to the antisocial behavior associated with psychopathy. Current evidence suggests that, for this subset of youth, the structure and function of neural circuitry supporting emotion processing, reward learning, decision making, and the development of emotion related to empathy may be crucial to understanding why they are at risk for violence. In particular, a reward dominant pattern of neurobehavioral conditioning may explain how these youth progress to some of the most severe and persistent forms of violence. However, this pattern of conditioning may also be essential to the primary prevention of such deleterious behavior. We suspect that effective strategies to prevent such violence may ultimately be informed by understanding these affective and motivational mechanisms.

Reduced emotional empathy in adults with subclinical ADHD: evidence from the empathy and systemizing quotient

Studies in children with ADHD suggest impairments in social cognitive functions, whereas studies in adults with ADHD are scarce and inconclusive. The aim of this study was to investigate the relationship between ADHD traits and self-reported social cognitive style in a sample of adults from the general population. For this purpose, a community sample of 685 adults filled out online self-report questionnaires about ADHD symptoms (ADHD Rating Scale, ARS), social cognitive functioning and friendships. The Empathy Quotient (EQ) with the subscales Cognitive Empathy (CE), Emotional Empathy (EE) and Social Skills (SS), and the Systemizing Quotient (SQ) were included for measuring social cognitive style and the Friendship Questionnaire (FQ) for the quality of friendships. Participants who met the DSM-5 criteria on the ARS (‘subclinical ADHD’; n = 56) were compared regarding their social cognitive functioning scores with a control group (n = 56) that was matched for age, sex and student status. With small effect sizes, the subclinical ADHD group showed reduced EE scores on the EQ and a more male social cognitive profile. This result was not influenced by sex or ADHD subtype. This study points to a relationship between traits of ADHD and the emotional aspect of empathy, whereas more complex aspects of empathy were unrelated. These findings should be corroborated in clinical patients with ADHD, employing neuropsychological tests rather than self-report questionnaires.

COMT and DAT1 genes are associated with hyperactivity and inattention traits in the 1993 Pelotas Birth Cohort: evidence of sex-specific combined effect

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) symptoms are dimensionally distributed in the population. This study aimed to assess the role of the catechol-O-methyltransferase (COMT) and of the dopamine transporter (DAT1) genes on ADHD symptoms in the general population.

METHODS

We investigated 4101 individuals from the 1993 Pelotas Birth Cohort Study using the parent version of the Strengths and Difficulties Questionnaire (SDQ) at ages 11 and 15 years. The SDQ hyperactivity/inattention scores were the main outcomes.

RESULTS

Linear regression analyses demonstrated that the increasing number of COMT158Val and DAT1 10R alleles significantly predicted increasing SDQ hyperactivity/inattention scores in boys at both 11 and 15 years of age (β coefficient = 0.049, t = 2.189, p = 0.029, R² = 0.012, and β coefficient = 0.064, t = 2.832, p = 0.005, R² = 0.008, respectively). The presence of both COMT158Val and DAT1 10R alleles was also associated with full categorical ADHD diagnosis at 18 years of age in boys (χ² = 4.561, p = 0.033, odds ratio 2.473, 95% confidence interval 1.048-5.838) from this cohort. We did not observe these associations in girls.

LIMITATIONS

Our analyses of SDQ hyperactivity/inattention scores were not corrected for SDQ scores of conduct problems because these variables were highly correlated.

CONCLUSION

This study demonstrates a role for COMT and DAT1 genes on hyperactivity/inattention symptoms and provides further support for ADHD as the extreme of traits that vary in the population. It also confirms previous evidence for sexual dimorphism on COMT and DAT1 gene expression.

Psychopathic traits mediate the association of serotonin transporter genotype and child externalizing behavior

Although the promoter polymorphism of the serotonin transporter (5-HTTLPR) gene is associated with externalizing behavior, its mediating pathways are unknown. Given their sensitivity to serotonin neurotransmission and unique association with attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD), we tested callous-unemotional (CU) traits and narcissism as separate mediators of the association of 5-HTTLPR with ADHD and ODD. We evaluated 209 5-9 year-old children with and without ADHD at baseline; approximately 2 years later (i.e., Wave 2), parents and teachers separately rated ADHD and ODD symptoms and youth self-reported antisocial behavior. Controlling for race-ethnicity and baseline ADHD/ODD, narcissism uniquely mediated predictions of multi-informant rated Wave 2 ADHD and ODD from variation in 5-HTTLPR; CU traits mediated predictions of Wave 2 ADHD from variations in 5-HTTLPR, but did not mediate the associations of 5-HTTLPR with ODD or youth self-reported antisocial behavior. Specifically, the number of 5-HTTLPR long alleles positively predicted CU traits and narcissism; narcissism was positively associated with Wave 2 ADHD and ODD symptoms, whereas CU traits were positively associated with Wave 2 ADHD. Child sex also moderated indirect effects of CU traits and narcissism, such that narcissism mediated predictions of ADHD/ODD in girls but not boys. Psychopathic traits may represent a relevant pathway underlying predictions of prospective change in ADHD and ODD from 5-HTTLPR, particularly in girls. We consider the role of psychopathic traits as a potential intermediate phenotype in genetically sensitive studies of child psychopathology. Aggr. Behav. 42:455-470, 2016. © 2016 Wiley Periodicals, Inc.

Why psychopathy matters: Implications for public health and violence prevention

Psychopathy is an early-appearing risk factor for severe and chronic violence. The violence largely attributable to psychopathy constitutes a substantial portion of the societal burden to the public health and criminal justice systems, and thus necessitates significant attention from prevention experts. Yet, despite a vast base of research in psychology and criminology, the public health approach to violence has generally neglected to consider this key variable. Fundamentally, the public health approach to violence prevention is focused on achieving change at the population level to provide the most benefit to the maximum number of people. Increasing attention to the individual-level factor of psychopathy in public health could improve our ability to reduce violence at the community and societal levels. We conclude that the research literature on psychopathy points to a pressing need for a broad-based public health approach with a focus on primary prevention. Further, we consider how measuring psychopathy in public health research may benefit violence prevention, and ultimately society, in general.

Callous-unemotional traits as a cross-disorders construct

PURPOSE

Callous-unemotional (CU) traits are currently viewed as the defining signs and symptoms of juvenile psychopathy. It is unclear, however, whether CU traits have validity only in the context of conduct disorder (CD) as proposed by Frick and Moffitt (A proposal to the DSM-V childhood disorders and the ADHD and disruptive behavior disorders work groups to include a specifier to the diagnosis of conduct disorder based on the presence of callous-unemotional traits, American Psychiatric Association, Washington, DC, 2010), or also outside CD, either in combination with other forms of psychopathology or as a stand-alone construct.

METHODS

The current review systematically studied the existent literature on CU traits in juveniles to examine their validity inside and outside CD according to the framework regarding the validity of a psychiatric diagnosis provided by Robins and Guze (Am J Psychiatry 126:983-987, 1970).

RESULTS

Inside youth with conduct problems, and CD specifically, it seems that CU traits meet the Robins and Guze criteria. As many of the reviewed studies included youth with ODD and ADHD as well, there are indications the same might be true for ODD and ADHD, although probably to a lesser extent. In other disorders, CU traits may be present as well, but their role is not firmly established. As stand-alone construct, data are lacking or are scarce on all of the above-mentioned criteria.

CONCLUSIONS

CU traits are a useful specifier in CD, and possibly also in disruptive behaviour disorders (DBDs) more generally. High CU traits outside DBDs exist but it is as yet unknown if there is a clinical need for defining CU traits as a stand-alone construct.

Clinical and cognitive characteristics of children with attention-deficit hyperactivity disorder, with and without copy number variants

BACKGROUND

Submicroscopic, rare chromosomal copy number variants (CNVs) contribute to neurodevelopmental disorders but it is not known whether they define atypical clinical cases.

AIMS

To identify whether large, rare CNVs in attention-deficit hyperactivity disorder (ADHD) are confined to a distinct clinical subgroup.

METHOD

A total of 567 children with ADHD aged 5-17 years were recruited from community clinics. Psychopathology was assessed using the Child and Adolescent Psychiatric Assessment. Large, rare CNVs (>500 kb, <1% frequency) were defined from single nucleotide polymorphism data.

RESULTS

Copy number variant carriers (13.6%) showed no differences from non-carriers in ADHD symptom severity, symptom type, comorbidity, developmental features, family history or pre-/perinatal markers. The only significant difference was a higher rate of intellectual disability (24% v. 9%, χ(2) = 15.5, P = 0.001). Most CNV carriers did not have intellectual disability.

CONCLUSIONS

Large, rare CNVs are not restricted to an atypical form of ADHD but may be more highly enriched in children with cognitive problems.

Juvenile offenders assessment

PURPOSE OF REVIEW

Evaluation of juveniles is an integral process that includes a broad bio-psycho-social clinical perspective together with the use of auxiliary instruments. The aim of this review is to report relevant issues for this process found in recent publications.

RECENT FINDINGS

Several evidences lead to broadening the assessment process of children and youngsters to include family functioning style. Mental health services allow the evaluation of multiple factors associated with antisocial behavior that may lead to devising preventive actions. In the Juvenile Justice System a wide-ranging evaluation must include the exploration of general personality characteristics and psychopathic traits in particular; attention deficit/hyperactivity disorder; intelligence; substance abuse and conduct disorder must be considered.

SUMMARY

A number of factors that have an impact on juvenile antisocial behavior have been identified and can be assessed using the appropriate methodology. The exploration of these factors at different developmental stages and in their various manifestations provide guidelines for devising preventive and therapeutic actions as well as for supporting judicial decisions. Though enriching the present state of the art is always a challenge, it is imperative to encourage the governments to utilize this knowledge to improve the care system of children and adolescents.

Unpacking the association: Individual differences in the relation of prenatal exposure to cigarettes and disruptive behavior phenotypes

Prenatal exposure to cigarettes has been robustly associated with disruptive behavior in diverse samples and across developmental periods. In this paper we aim to elucidate exposure related behavioral phenotypes and developmental pathways by testing: (a) differential associations of exposure and four disruptive behavior dimensional phenotypes: Aggression, Noncompliance, Temper Loss and Low Concern for Others; and (b) moderation of these pathways including sex differences and moderation by parental responsive engagement. Participants were 211 teens and their parents from the East Boston Family Study (EBFS), an adolescent follow-up of a pregnancy cohort over-sampled for exposure. A best estimate serum cotinine corrected score was used to characterize exposure. In multivariate models controlling for parental antisocial behavior, family adversity and secondhand exposure, exposure uniquely predicted Aggression and Noncompliance. Paternal responsiveness moderated exposure effects on disruptive behavior. There were no sex differences in these patterns. Phenotypic findings suggest the possibility of specific neural mechanisms. In conjunction with prior research, protective effects of parental responsiveness occurring as late as adolescence point to the potential benefit of parenting-based prevention efforts to reduce risk to exposed offspring.

Revisiting Lynam's notion of the "fledgling psychopath": are HIA-CP children truly psychopathic-like?

BACKGROUND

In his developmental model of emerging psychopathy, Lynam proposed that the "fledgling psychopath" is most likely to be located within a subgroup of children elevated in both hyperactivity/inattention/impulsivity (HIA) and conduct problems (CP). This approach has garnered some empirical support. However, the extent to which Lynam's model captures children who resemble psychopathy with regard to the core affective and interpersonal features remains unclear.

METHODS

In the present study, we investigated this issue within a large community sample of youth (N = 617). Four groups (non-HIA-CP, HIA-only, CP-only, and HIA-CP), defined on the basis of teacher reports of the Strengths and Difficulties Questionnaire (SDQ), were compared with respect to parent-reported psychopathic-like traits and subjective emotional reactivity in response to unpleasant, emotionally-laden pictures from the International Affective Pictures System (IAPS).

RESULTS

Results did not support Lynam's model. HIA-CP children did not appear most psychopathic-like on dimensions of callous-unemotional and narcissistic personality, nor did they report reduced emotional reactivity to the IAPS relative to the other children. Post-hoc regression analyses revealed a significant moderation such that elevated HIA weakened the association between CP and emotional underarousal.

CONCLUSIONS

Implications of these findings with regard to the development of psychopathy are discussed.

Adolescent clinical outcomes for young people with attention-deficit hyperactivity disorder

BACKGROUND

Attention-deficit hyperactivity disorder (ADHD) is recognised as a common, disabling condition. Little information is available regarding the long-term outcomes for individuals with ADHD in the UK.

AIMS

To examine the 5-year outcome for a UK cohort of children with diagnosed, treated ADHD and identify whether maternal and social factors predict key outcomes.

METHOD

One hundred and twenty-six school-aged children (mean age 9.4 years, s.d. = 1.7) diagnosed with ADHD were reassessed 5 years later during adolescence (mean age 14.5 years, s.d. = 1.7) for ADHD, conduct disorder and other antisocial behaviours.

RESULTS

Most adolescents (69.8%) continued to meet full criteria for ADHD, were known to specialist services and exhibited high levels of antisocial behaviour, criminal activity and substance use problems. Maternal childhood conduct disorder predicted offspring ADHD continuity; maternal childhood conduct disorder, lower child IQ and social class predicted offspring conduct disorder symptoms.

CONCLUSIONS

The treatment and monitoring of ADHD need to be intensified as outcomes are poor especially in offspring of mothers with childhood conduct disorder symptoms.

The relation of ADHD and violent aggression: What can we learn from epidemiological and genetic studies?

Disruptive behavior includes psychopathological and behavioral constructs like aggression, impulsivity, violence, antisociality and psychopathy and is often closely related with diagnostic categories like conduct disorder (CD), attention deficit disorder (ADHD) and antisocial personality disorder (ASP). There is now clear evidence that neurobiological and environmental factors contribute to these phenotypes. A mounting body of evidence also suggests interactive effects of genetic and environmental risks. In this selective review we give an overview over epidemiological aspects of the relation between ADHD and antisocial behavior, including violent aggression and psychopathy. Moreover, we summarize recent findings from molecular genetic studies and particularly discuss pleiotropic effects of a functional polymorphism of the serotonin transporter promoter gene (5HTTLPR) and childhood adversity on ADHD and violent behavior. The reported gene-environment interactions are not only informative for understanding the neurobiological underpinnings of disruptive behavior, but also throw some light on the relation between ADHD and violent behavior from a genetic perspective. The impact of genetic research on forensic psychiatry and future directions of neurobiological research are discussed.