Evaluating the sensitivity to threat and affiliative reward (STAR) model in relation to the development of conduct problems and callous-unemotional traits across early adolescence.

BACKGROUND: The Sensitivity to Threat and Affiliative Reward (STAR) model proposes low threat sensitivity and low affiliation as risk factors for callous-unemotional (CU) traits. Preliminary evidence for the STAR model comes from work in early childhood. However, studies are needed that explore the STAR dimensions in late childhood and adolescence when severe conduct problems (CP) emerge. Moreover, it is unclear how variability across the full spectrum of threat sensitivity and affiliation gives rise to different forms of psychopathology beyond CU traits. METHODS: The current study addressed these gaps using parent- and child-reported data from three waves and a sub-study of the Adolescent Brain Cognitive Development Study® of 11,878 youth (48% female; ages 9-12). RESULTS: Consistent with the STAR model, low threat sensitivity and low affiliation were independently related to CU traits across informants and time. Moreover, there was significant interaction between the STAR dimensions, such that children with lower sensitivity to threat and lower affiliation had higher parent-reported CU traits. Unlike CU traits, children with higher threat sensitivity had higher parent-reported CP and anxiety. Finally, children with lower affiliation had higher parent-reported CP, anxiety, and depression. Results largely replicated across informants and time, and sensitivity analysis revealed similar findings in children with and without DSM-5 defined CP. CONCLUSIONS: Results support the STAR model hypotheses as they pertain to CU traits and delineate threat sensitivity and affiliation as independent transdiagnostic risk factors for different types of psychopathology. Future research is needed to develop fuller and more reliable and valid measures of affiliation and threat sensitivity across multiple assessment modalities.

The Proposed Specifiers for Conduct Disorder (PSCD) in Iranian School-Attending Adolescents: A Multi-Informant Validation Study of the PSCD Parent- and Youth Self-Report Versions.

The Proposed Specifier for Conduct Disorder (PSCD) was developed to measure the broad psychopathy construct with grandiose-manipulative, callous-unemotional, daring-impulsive, and conduct disorder subscales. This study tested the psychometric properties of Persian parent-and-child self-report PSCD versions with 974 parents (86% mothers) and children/adolescents (46.5% boys) dyads. Results showed that with some modifications the proposed hierarchical four-factor structure for both PSCDs was confirmed and was found to be invariant across gender. Across versions, all PSCD scores were internally consistent and demonstrated expected correlations with parent-reported externalizing problems, anxiety/depression, and poor school performance, supporting the PSCDs scores' validity. This study also is the first to examine and establish acceptable to excellent parent-child agreement of PSCD scores. Finally, all PSCD child-report scores offered small though significant incremental validity over their corresponding PSCD parent-version scores in predicting parent-reported conduct problems and proactive aggression. Findings indicated that both Persian PSCDs may hold promise for assessing psychopathy components in Iranian school-attending adolescents and generating additional research on this topic.

Integrative Multi-omics Analysis of Childhood Aggressive Behavior.

This study introduces and illustrates the potential of an integrated multi-omics approach in investigating the underlying biology of complex traits such as childhood aggressive behavior. In 645 twins (cases = 42%), we trained single- and integrative multi-omics models to identify biomarkers for subclinical aggression and investigated the connections among these biomarkers. Our data comprised transmitted and two non-transmitted polygenic scores (PGSs) for 15 traits, 78,772 CpGs, and 90 metabolites. The single-omics models selected 31 PGSs, 1614 CpGs, and 90 metabolites, and the multi-omics model comprised 44 PGSs, 746 CpGs, and 90 metabolites. The predictive accuracy for these models in the test (N = 277, cases = 42%) and independent clinical data (N = 142, cases = 45%) ranged from 43 to 57%. We observed strong connections between DNA methylation, amino acids, and parental non-transmitted PGSs for ADHD, Autism Spectrum Disorder, intelligence, smoking initiation, and self-reported health. Aggression-related omics traits link to known and novel risk factors, including inflammation, carcinogens, and smoking.

Validation of the Proposed Specifiers for Conduct Disorder (PSCD) Self-Report Version in Iranian School-Attending Adolescents.

The Proposed Specifiers for Conduct Disorder (PSCD) scale was developed to advance the study of child and adolescent psychopathy, especially as it relates to conduct disorder. This study is the first to test the factor structure, measurement invariance, internal consistency, and validity of the Persian PSCD self-report version in a gender-mixed sample of 1,506 school-attending 11 to 18 years old youth (M age = 15.23; SD = 1.83; 49.60% boys). Confirmatory factor analysis supported the proposed four-factor hierarchical structure of the PSCD, though with 19 items loaded on grandiose-manipulative, callous-unemotional, daring-impulsive, and conduct disorder components. This factor structure was also invariant across gender. The PSCD total and four components scores were internally consistent and exhibited the expected relations with proactive aggression, externalizing problems, anxiety and depression, and poor school performance, supporting the PSCD scores' convergent, discriminant, and criteria validity. The findings indicated that with some modifications, the Persian PSCD might hold promise for assessing psychopathy components in Iranian school-attending adolescents and may spark additional research in a variety of settings.

DNA methylation signatures of aggression and closely related constructs: A meta-analysis of epigenome-wide studies across the lifespan.

DNA methylation profiles of aggressive behavior may capture lifetime cumulative effects of genetic, stochastic, and environmental influences associated with aggression. Here, we report the first large meta-analysis of epigenome-wide association studies (EWAS) of aggressive behavior (N = 15,324 participants). In peripheral blood samples of 14,434 participants from 18 cohorts with mean ages ranging from 7 to 68 years, 13 methylation sites were significantly associated with aggression (alpha = 1.2 × 10-7; Bonferroni correction). In cord blood samples of 2425 children from five cohorts with aggression assessed at mean ages ranging from 4 to 7 years, 83% of these sites showed the same direction of association with childhood aggression (r = 0.74, p = 0.006) but no epigenome-wide significant sites were found. Top-sites (48 at a false discovery rate of 5% in the peripheral blood meta-analysis or in a combined meta-analysis of peripheral blood and cord blood) have been associated with chemical exposures, smoking, cognition, metabolic traits, and genetic variation (mQTLs). Three genes whose expression levels were associated with top-sites were previously linked to schizophrenia and general risk tolerance. At six CpGs, DNA methylation variation in blood mirrors variation in the brain. On average 44% (range = 3-82%) of the aggression-methylation association was explained by current and former smoking and BMI. These findings point at loci that are sensitive to chemical exposures with potential implications for neuronal functions. We hope these results to be a starting point for studies leading to applications as peripheral biomarkers and to reveal causal relationships with aggression and related traits.

Classes of Oppositional Defiant Disorder Behavior in Clinic-referred Children and Adolescents: Concurrent Features and Outcomes: Classification Des Comportements Dans le Trouble Oppositionnel Avec Provocation Chez Des Enfants et des Adolescents Aiguillés à Une Clinique: Caractéristiques Co-occurrentes et Résultats.

OBJECTIVE: Oppositional defiant disorder (ODD) consists of irritable and oppositional behaviors, both of which are associated with different problems. However, it is unclear whether irritability and oppositionality enable classification of clinic-referred children and adolescents into mutually exclusive groups (e.g., high in oppositionality, low in irritability), and whether this classification is clinically meaningful. METHOD: As part of a clinical protocol, ODD behaviors were assessed at referral through a comprehensive diagnostic interview and questionnaire. Parent- and teacher-reported ODD of 2,185 clinic-referred 5- to 18-year-olds (36.9% females) were used in latent class analysis. Resulting ODD classes were compared, concurrently at referral, and, longitudinally at the end of the diagnostic and treatment process, on various clinically relevant measures that were completed by various informants, including mental health problems, global functioning, and Diagnostic and Statistical Manual of Mental Disorders (DSM) classifications. RESULTS: Three classes emerged with high, moderate, and low levels of both irritability and oppositionality. At referral, the high class experienced the highest levels of mental health problems and DSM classifications. Importantly, all ODD classes defined at intake were predictive of diagnostic and treatment outcomes months later. Notably, the high class had higher rates of clinician-based classifications of ODD and conduct disorder, and the lowest levels of pre- and posttreatment global functioning. Additionally, the low class exhibited higher rates of generalized anxiety disorder and fear disorders. CONCLUSIONS: Irritability and oppositionality co-occur in clinic-referred youths to such an extent that classification based on these behaviors does not add to clinical inference. Instead, findings suggest that the overall ODD severity at referral should be used as a guidance for treatment.

Towards Integrated Youth Care: A Systematic Review of Facilitators and Barriers for Professionals.

To overcome fragmentation in support for children and their families with multiple and enduring problems across life domains, professionals increasingly try to organize integrated care. However, it is unclear what facilitators and barriers professionals experience when providing this integrated care. Our systematic review, including 55 studies from a broad variety of settings in Youth Care, showed that integrated care on a professional level is a multi-component entity consisting of several facilitators and barriers. Findings were clustered in seven general themes: 'Child's environment', 'Preconditions', 'Care process', 'Expertise', 'Interprofessional collaboration', 'Information exchange', and 'Professional identity'. The identified facilitators and barriers were generally consistent across studies, indicating broad applicability across settings and professional disciplines. This review clearly shows that when Youth Care professionals address a broad spectrum of problems, a variety of facilitators and barriers should be considered.Registration PROSPERO, registration number CRD42018084527.

The prospective usefulness of callous-unemotional traits and conduct disorder in predicting treatment engagement among detained girls.

Although treatment engagement (TE) is crucial for treatment success it is not well known how likely detained girls are to engage in treatment and what features may impede them from doing so. This study is the first to examine the prognostic usefulness of two features of potential interest, being callous-unemotional (CU) traits and conduct disorder (CD), in relation to TE. Detained girls and their parents (n = 75) were interviewed with the Diagnostic Interview Schedule for Children to assess CD, and completed the Antisocial Process Screening Device to assess CU traits dimensionally and categorically as in the new diagnostic and statistical manual of mental disorders, fifth edition (DSM-5) CU-based specifier. One to two months later, the girls reported how much they engaged in treatment. At the zero-order level, self-, but not parent-reported CU traits and CD were predictive of lower levels of TE. The incorporation of CU traits into a diagnosis of CD identified girls with lower levels of future TE, a finding that held across different informants. Of note, the aforementioned findings only became apparent when using a dimensional measure of CU traits, and not when using the categorical measure of CU traits currently included in DSM-5. This study showed that CU traits can help developing an understanding of what factors hinder TE among detained girls. Our findings also support recommendations to incorporate CU traits into the CD diagnosis, and suggest that dimensional approaches to do so may yield relevant information about future levels of TE.

Psychopathic personality traits in 5 year old twins: the importance of genetic and shared environmental influences.

There is limited research on the genetic and environmental bases of psychopathic personality traits in children. In this study, psychopathic personality traits were assessed in a total of 1189 5-year-old boys and girls drawn from the Preschool Twin Study in Sweden. Psychopathic personality traits were assessed with the Child Problematic Traits Inventory, a teacher-report measure of psychopathic personality traits in children ranging from 3 to 12 years old. Univariate results showed that genetic influences accounted for 57, 25, and 74 % of the variance in the grandiose-deceitful, callous-unemotional, and impulsive-need for stimulation dimensions, while the shared environment accounted for 17, 48 and 9 % (n.s.) in grandiose-deceitful and callous-unemotional, impulsive-need for stimulation dimensions, respectively. No sex differences were found in the genetic and environmental variance components. The non-shared environment accounted for the remaining 26, 27 and 17 % of the variance, respectively. The three dimensions of psychopathic personality were moderately correlated (0.54-0.66) and these correlations were primarily mediated by genetic and shared environmental factors. In contrast to research conducted with adolescent and adult twins, we found that both genetic and shared environmental factors influenced psychopathic personality traits in early childhood. These findings indicate that etiological models of psychopathic personality traits would benefit by taking developmental stages and processes into consideration.

Dissociable relations between amygdala subregional networks and psychopathy trait dimensions in conduct-disordered juvenile offenders.

Psychopathy is a serious psychiatric phenomenon characterized by a pathological constellation of affective (e.g., callous, unemotional), interpersonal (e.g., manipulative, egocentric), and behavioral (e.g., impulsive, irresponsible) personality traits. Though amygdala subregional defects are suggested in psychopathy, the functionality and connectivity of different amygdala subnuclei is typically disregarded in neurocircuit-level analyses of psychopathic personality. Hence, little is known of how amygdala subregional networks may contribute to psychopathy and its underlying trait assemblies in severely antisocial people. We addressed this important issue by uniquely examining the intrinsic functional connectivity of basolateral (BLA) and centromedial (CMA) amygdala networks in relation to affective, interpersonal, and behavioral traits of psychopathy, in conduct-disordered juveniles with a history of serious delinquency (N = 50, mean age = 16.83 ± 1.32). As predicted, amygdalar connectivity profiles exhibited dissociable relations with different traits of psychopathy. Interpersonal psychopathic traits not only related to increased connectivity of BLA and CMA with a corticostriatal network formation accommodating reward processing, but also predicted stronger CMA connectivity with a network of cortical midline structures supporting sociocognitive processes. In contrast, affective psychopathic traits related to diminished CMA connectivity with a frontolimbic network serving salience processing and affective responding. Finally, behavioral psychopathic traits related to heightened BLA connectivity with a frontoparietal cluster implicated in regulatory executive functioning. We suggest that these trait-specific shifts in amygdalar connectivity could be particularly relevant to the psychopathic phenotype, as they may fuel a self-centered, emotionally cold, and behaviorally disinhibited profile. Hum Brain Mapp 37:4017-4033, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

Different brain responses during empathy in autism spectrum disorders versus conduct disorder and callous-unemotional traits.

BACKGROUND: Deficits in empathy are reported in autism spectrum disorders (ASD) and also underlie antisocial behavior of individuals with conduct disorder and callous-unemotional traits (CD/CU+). Many studies suggest that individuals with ASD are typically impaired in cognitive aspects of empathy, and individuals with CD/CU+ typically in affective aspects. In the current study, we compared the neural correlates of cognitive and affective aspects of empathy between youth with ASD and youth with CD/CU+. METHODS: Functional magnetic resonance imaging (fMRI) was used to assess boys with ASD (N = 23), boys with CD/CU+ (N = 23), and typically developing (TD) boys (N = 33), aged 15-19 years. Angry and fearful faces were presented and participants were asked to either infer the emotional state from the face (other-task; emotion recognition) or to judge their own emotional response to the face (self-task; emotional resonance). RESULTS: During emotion recognition, boys with ASD showed reduced responses compared to the other groups in the ventromedial prefrontal cortex (vmPFC). During emotional resonance, the CD/CU+ and ASD groups showed reduced amygdala responses compared to the TD controls, boys with ASD showed reduced responses in bilateral hippocampus, and the CD/CU+ boys showed reduced responses in the inferior frontal gyrus (IFG) and anterior insula (AI). CONCLUSION: Results suggest differential abnormal brain responses associated with specific aspects of empathic functioning in ASD and CD/CU+. Decreased amygdala responses in ASD and CD/CU+ might point to impaired emotion processing in both disorders, whereas reduced vmPFC responses suggest problems in processing cognitive aspects of empathy in ASD. Reduced IFG/AI responses, finally, suggest decreased emotional resonance in CD/CU+.

The clinical usefulness of the new LPE specifier for subtyping adolescents with conduct disorder in the DSM 5.

In DSM 5, conduct disorder (CD) has been expanded with a new specifier 'with Limited Prosocial Emotions' (LPE) in addition to the age-of-onset (AoO) subtyping, and is thought to identify a severe antisocial subgroup of CD. However, research in clinical practice has been scarce. Therefore, the current study will examine differences in clinical symptoms between subtypes of CD, based on both subtyping schemes. Subsequently, it will investigate whether the LPE specifier explains unique variance in aggression, added to the AoO subtyping. A sample of 145 adolescents with CD (51 % male, mean age 15.0) from a closed treatment institution participated in this study. CD diagnoses and AoO subtype were assessed using a structured diagnostic interview. The LPE specifier was assessed using the callous-unemotional dimension of the Youth Psychopathy Traits Inventory (YPI). Self-reported proactive and reactive aggression, rule-breaking behavior and internalizing problems within the subtypes were compared. Youth with childhood-onset CD and LPE showed significantly more aggression than adolescent-onset CD without LPE (proactive aggression: F = 3.1, p < 0.05, reactive aggression: F = 3.7, p < 0.05). Hierarchical regression revealed that the LPE specifier uniquely explained 7 % of the variance in reactive aggression, additionally to the AoO subtyping. For proactive aggression, the interaction between AoO and the LPE added 4.5 % to the explained variance. Although the LPE specifier may help to identify a more aggressive subtype of CD in adolescents, the incremental utility seems to be limited. Therefore, clinical relevance of the LPE specifier in high-risk adolescent samples still needs to be investigated thoroughly.

Validation of the Greek Cypriot Translation of the Triarchic Psychopathy Measure.

Psychopathy is conceived of as a pathological constellation of personality traits, manifested in aberrant behavioral, interpersonal, and emotional tendencies. This study examined within a Greek-speaking nonclinical sample (N = 419) associations between differing phenotypic dimensions of psychopathy (boldness, meanness, disinhibition) assessed via the Triarchic Psychopathy Measure (TriPM) and self-report criterion measures of psychopathology, personality, and history of abuse and neglect. Consistent with predictions of the triarchic model of psychopathy, evidence was found for distinct correlates of the 3 phenotypic dimensions. Boldness was associated with both adaptive (immunity to anxiety/distress, fearlessness, low hostility) and maladaptive tendencies (grandiose manipulative traits, Machiavellian features including desire for control/status, and verbal aggression). Meanness was related to callous and unemotional traits, features of Machiavellianism (e.g., amoral manipulation and distrust of others), physical aggression, and absence of positive parenting. Disinhibition, by contrast, was characterized by anxiety and distress, exposure to violence, and retrospective accounts of abuse history, along with impulsive, irresponsible, and hostile tendencies. These findings indicate that the Greek-Cypriot translation of the TriPM effectively assesses the constructs of the triarchic model and extend what we know about their empirical correlates.

Assessing Reactive and Proactive Aggression in Detained Adolescents Outside of a Research Context.

The Reactive Proactive Aggression Questionnaire (RPQ) is a self-report tool for assessing reactive aggression (RA) and proactive aggression (PA). This study contributes to the literature by testing the psychometric properties of the RPQ across detained boys from various ethnicities whilst using data that were gathered during clinical assessments. The factorial, convergent, and criterion validity, and the internal consistency of the RPQ scores received strong support in the total sample and across four ethnicity groups. Also, three groups of boys were identified, with the group including boys with high levels of both RA and PA including the most severe boys in terms of anger, delinquency, alcohol/drug use, and psychopathic traits, and having the highest prevalence rate of conduct disorder and substance use disorder. Together, these findings suggest that the RPQ may hold promise for assessing RA and PA in detained boys, even when confidentiality and anonymity of the information is not guaranteed.

Psychometric Properties of the Original and Short Form of the Inventory of Callous-Unemotional Traits in Detained Female Adolescents.

This study examines the psychometric properties of the self-report version of the Inventory of Callous-Unemotional Traits in 191 detained female adolescents (M = 15.76, SD = 1.02). Evidence supporting the validity of the ICU scores was generally weak, largely due to poor functioning of the Unemotional subscale. Results from confirmatory factor analyses demonstrated support for a recently proposed shortened version of the ICU consisting of two subscales (Callousness and Uncaring). Both subscales showed acceptable to good internal consistency. This short-form version also improved criterion validity, though some issues regarding its convergent validity need further consideration. In conclusion, this study suggests that a short-form version of the ICU that includes a subset of the original items may hold promise as an efficient and valid method for assessing CU traits.

Early Childhood Trajectories of Conduct Problems and Callous-Unemotional Traits: The Role of Fearlessness and Psychopathic Personality Dimensions.

Children with early onset of conduct problems (CP) are at risk for long lasting psychosocial problems, especially if CP co-occurs with callous-unemotional (CU) traits. Joint trajectories of CP and CU traits during early childhood were identified using data from the SOFIA study, following 2031 children longitudinally from ages 3-5 to 5-7 years. The results showed that children exhibiting stable high CP and CU traits were characterized by high levels of fearlessness, and psychopathic traits, including grandiose-deceitfulness, and impulsivity, need for stimulation. Children with decreasing or increasing CP and CU traits were characterized by decreases and increases respectively in their levels of fearlessness and psychopathic traits. Children high on CP and low on CU traits exhibited lower levels of these dimensions. Thus, stability and change of fearlessness and psychopathic traits are associated with stability and change in CP and CU traits, making these temperamental and personality traits promising target candidates for early intervention.

The clinical usefulness of the DSM-5 specifier for conduct disorder outside of a research context.

The Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5) specifier 'with Limited Prosocial Emotions' (LPE) is expected to provide information about impairment of adolescents with conduct disorder (CD) and to designate a severe subgroup of antisocial youths. This study is the first to scrutinize the clinical usefulness of this LPE specifier outside of a research context. Standardized questionnaires and diagnostic interviews were administered to 380 detained boys as part of a clinical protocol. Boys with CD that met criteria for the LPE specifier did not significantly differ from CD boys without LPE on any of the variables of interest. When using a CD diagnosis by itself (that is, without linking it to the LPE specifier) boys with CD were significantly more psychiatrically disturbed, rule-breaking, reactively and proactively aggressive, and reported more violent and nonviolent offenses than boys without CD. These differences were also revealed while using the LPE specifier by itself (that is, without linking it to a CD diagnosis). Additional analyses, nevertheless, showed that the magnitude of the group differences was strong when using a CD diagnosis by itself, but weak to moderate when using the LPE specifier by itself, or when incorporating the LPE specifier into a diagnosis of CD as recommended by the DSM-5. Altogether, this study suggests that incorporating the LPE specifier into CD is of restricted usefulness to discriminate between detained boys with varying levels of psychiatric problems and antisocial behavior. Interestingly, a CD diagnosis by itself seems the most clinically useful measure to identify a troubled group of detained boys. (PsycINFO Database Record

Quality of life in relation to future mental health problems and offending: Testing the good lives model among detained girls.

Detained girls bear high levels of criminal behavior and mental health problems that are likely to persist into young adulthood. Research with these girls began primarily from a risk management perspective, whereas a strength-based empowering perspective may increase knowledge that could improve rehabilitation. This study examines detained girls' quality of life (QoL) in relation to future mental health problems and offending, thereby testing the strength-based good lives model of offender rehabilitation (GLM). At baseline, 95 girls (Mage = 16.25) completed the World Health Organization QoL instrument to assess their QoL prior to detention in the domains of physical health, psychological health, social relationships, and environment. Six months after discharge, mental health problems and offending were assessed by self-report measures. Structural equation models were conducted to test GLM's proposed (in)direct pathways from QoL (via mental health problems) toward offending. Although we could not find support for GLM's direct negative pathway from QoL to offending, our findings did provide support for GLM's indirect negative pathway via mental health problems to future offending. In addition, we found a direct positive pathway from detained girls' satisfaction with their social relationships to offending after discharge. The current findings support the potential relevance of addressing detained girls' QoL, pursuing the development of new skills, and supporting them to build constructive social contacts. Our findings, however, also show that clinicians should not only focus on strengths but that detecting and modifying mental health problems in this vulnerable group is also warranted. (PsycINFO Database Record

Mental health problems in young male offenders with and without sex offences: a comparison based on the MAYSI-2.

BACKGROUND: There is a need for better knowledge about the relationship between sexual offending by young people and mental health problems. AIM: This study aimed to compare mental health problems between young people who commit sexual offences and those who do not. METHODS: After completion of the Massachusetts Youth Screening Instrument-Version 2 (MAYSI-2), 334 young people who, according to MAYSI-2 information, had committed a sex offence were compared with 334 young people whose MAYSI-2 data suggested that they had not committed a sex offence. They were matched for age, race/ethnicity, type of facility and adjudication status. We also examined the young sex offenders for within group differences. RESULTS: The young sex offenders were less likely to report anger-irritability or substance misuse than the comparison youths. Within the sex offender group, older juveniles were more likely to report alcohol and drug use problems than younger ones, Caucasians were more likely to report anger and suicidal ideation than their non-Caucasian peers, those detained were more likely to report alcohol and drug use problems and somatic complaints than those on probation, and convicted youths were more likely to report alcohol and drug use problems and anger-irritability than those awaiting trial. CONCLUSIONS: Juvenile sexual offending seems less likely to be committed in the context of an anti-social lifestyle than other offending. Important findings among young sex offenders are their higher levels of mental health problems among those detained and convicted than among those on probation or awaiting trial. Assessment of the mental health of young sex offenders seems to be even more important the further they are into the justice system. Copyright © 2015 John Wiley & Sons, Ltd.

Physical and verbal aggressive behavior and COMT genotype: Sensitivity to the environment.

Catechol-O-methyltransferase (COMT) genotype has been implicated as a vulnerability factor for several psychiatric diseases as well as aggressive behavior, either directly, or in interaction with an adverse environment. The present study aimed at investigating the susceptibility properties of COMT genotype to adverse and favorable environment in relation to physical and verbal aggressive behavior. The COMT Val158Met polymorphism was genotyped in a Swedish population-based cohort including 1,783 individuals, ages 20-24 years (47% males). A significant three-way interaction was found, after correction for multiple testing, between COMT genotype, exposure to violence, and parent-child relationship in association with physical but not verbal aggressive behavior. Homozygous for the Val allele reported lower levels of physical aggressive behavior when they were exposed to violence and at the same time experienced a positive parent-child relationship compared to Met carriers. Thus, susceptibility properties of COMT genotype were observed in relation to physical aggressive behavior supporting the hypothesis that COMT genotypes are modifying the sensitivity to environment that confers either risk or protection for aggressive behavior. As these are novel findings, they warrant further investigation and replication in independent samples. © 2016 Wiley Periodicals, Inc.