Trauma, Genes, and the Neurobiology of Personality Disorders

Childhood traumata, Dexamethasone Suppression Test and psychiatric symptoms: a trans-diagnostic approach

BACKGROUND

Childhood traumatic events and functional abnormalities of the hypothalamus-pituitary-adrenal (HPA) axis have been widely reported in psychiatric patients, although neither is specific for any diagnosis. Among the limited number of studies that have evaluated these topics, none has adopted a trans-diagnostic approach. The aim of the present research is to explore the relationship between childhood stressors, HPA axis function and psychiatric symptoms, independent of the diagnosis.

METHOD

A total of 93 moderate to severely ill psychiatric out-patients of Florence and Pisa University Psychiatric Units and 33 healthy control subjects were recruited. The assessment consisted of salivary cortisol pre- and post-low dose (0.5 mg) Dexamethasone, early and recent life events, 121 psychiatric symptoms independent of diagnosis, SCID, BPRS.

RESULTS

In total, 33.5% of patients were Dexamethasone Suppression Test (DST) non-suppressors, compared with 6.1% of controls (p=0.001). Among patients, non-suppression was associated with particular symptoms (i.e. depressive and psychotic), but not to any specific diagnosis. Early stressful life events were significantly associated with higher salivary cortisol levels, with DST non-suppression and with approximately the same subset of symptoms. A recent stressful event seemed to be associated to the HPA response only in those subjects who were exposed to early traumata.

CONCLUSIONS

Our report suggests a relationship between life stress, HPA axis and psychopathology. A cluster of specific psychiatric symptoms seems to be stress related. Moreover, it seems that an abnormal HPA response is possibly triggered by an excessive pressure in vulnerable individuals.

Tryptophan-hydroxylase 2 haplotype association with borderline personality disorder and aggression in a sample of patients with personality disorders and healthy controls

BACKGROUND

There is a decreased serotonergic function in impulsive aggression and borderline personality disorder (BPD), and genetic association studies suggest a role of serotonergic genes in impulsive aggression and BPD. Only one study has analyzed the association between the tryptophan-hydroxylase 2 (TPH2) gene and BPD. A TPH2 "risk" haplotype has been described that is associated with anxiety, depression and suicidal behavior.

METHODS

We assessed the relationship between the previously identified "risk" haplotype at the TPH2 locus and BPD diagnosis, impulsive aggression, affective lability, and suicidal/parasuicidal behaviors, in a well-characterized clinical sample of 103 healthy controls (HCs) and 251 patients with personality disorders (109 with BPD). A logistic regression including measures of depression, affective lability and aggression scores in predicting "risk" haplotype was conducted.

RESULTS

The prevalence of the "risk" haplotype was significantly higher in patients with BPD compared to HCs. Those with the "risk" haplotype have higher aggression and affect lability scores and more suicidal/parasuicidal behaviors than those without it. In the logistic regression model, affect lability was the only significant predictor and it correctly classified 83.1% of the subjects as "risk" or "non-risk" haplotype carriers.

CONCLUSIONS

We found an association between the previously described TPH2 "risk" haplotype and BPD diagnosis, affective lability, suicidal/parasuicidal behavior, and aggression scores.

Corpus callosum morphology and relationship to orbitofrontal and lateral ventricular volume in teenagers with first-presentation borderline personality disorder

Previous studies have demonstrated alterations to fronto-limbic circuitry and callosal structure in borderline personality disorder (BPD). We predicted that a first-presentation BPD cohort who demonstrated orbitofrontal cortex (OFC) reductions would show regional reductions in the anterior corpus callosum.

METHOD

Twenty teenage first-presentation BPD patients and twenty matched healthy controls underwent Magnetic resonance imaging (MRI) was performed in 20 teenaged first-presentation BPD patients and 20 matched healthy controls. Corpus callosum size and shape and ventricular volume were estimated using established methods and compared between the two groups. The relationship between illness variables and callosal morphology was also examined. OFC volume was correlated with callosal and ventricular variables.

RESULTS

BPD participants and controls did not differ on measures of callosal size or shape, or ventricular size. BPD participants showed an alteration to the pattern of age-related expansions seen in the callosum. BPD participants with a history of trauma did not demonstrate significant neuroanatomical differences from those without. OFC volumes did not correlate with the thickness of the anterior corpus callosum.

CONCLUSION

Gross neuroanatomical changes are not present at the level of the callosum in teenagers with first-presentation BPD. Changes seen in other studies might reflect factors associated with the duration of BPD, such as recurrent comorbidity with axis I disorders, or treatment.

Early environmental predictors of the affective and interpersonal constructs of psychopathy

Early childhood maltreatment (i.e., physical, sexual, emotional abuse) and caregiver disruptions are hypothesized to be instrumental in altering the neurobiology of the brain, particularly the amygdala, and contributing to the development of the affective deficits examined in individuals with psychopathy. Exposure to early untoward life events in models of rodent and nonhuman primates changes the neurobiology of the stress response. It is hypothesized that these changes may permanently shape brain regions that mediate stress and emotion and therefore play a role in the etiology of affective disorders in humans. The significance of experience (e.g., the intensity/severity, chronicity/duration, and developmental timing of experiences) and how the accompanying changes in the activity of the hypothalamic-pituitary-adrenocortical system affect alterations in the amygdala are discussed as critical contributors to the etiology of psychopathy. A model is proposed in which early maltreatment experiences contribute to alterations to the amygdala and produce a blunted or dissociative response to stress, a key factor in the affective deficits observed in psychopaths.

Neuropsychological features of indigent murder defendants and death row inmates in relation to homicidal aspects of their crimes

Neuropsychological features of 77 indigent murder defendants and death row inmates were examined in relation to criminal variables underlying their homicidal acts. Clinically, the sample was characterized by elevated rates of developmental disorders (49%), personality disorders (54%), Axis I psychiatric disorders (45%), substance abuse (86%), and history of violence (43%). By statute, killing more than one person is an aggravating factor in many jurisdictions that renders a murder defendant eligible for the death penalty. Individuals who committed a single murder were characterized by executive dysfunction, lower intelligence, slower speed of information processing, and a higher frequency of developmental disorders (58%), relative to those charged and/or convicted of killing two or more people, who were characterized by a significantly higher rate of personality disorders (79%) and a lower rate of developmental disorders (34%). Additionally, using the FBI criminal classification system for categorizing homicide by motive, a significant difference in the frequency of psychosis was found among subgroups associated with the following motives: Criminal enterprise; personal cause; and sex. The collective neuropsychological profile of the sample revealed that executive functions were significantly decreased, relative to memory functions, with over half of the sample (55%) demonstrating executive dysfunction.

Neighborhoods and genes and everything in between: understanding adolescent aggression in social and biological contexts

Adolescent aggression was explored in relation to neighborhood and genetic characteristics. Child saturation (the proportion of the population consisting of children under the age of 15), ethnic heterogeneity, poverty, and urbanicity of neighborhoods were examined in relation to adolescent aggression in 12,098 adolescents followed longitudinally for 1 year. Longitudinal analyses indicated that child saturation was positively associated with increases in aggression, with this finding emerging among those living in the same neighborhood at both testing times and those who moved between testing times. In a subsample of males for whom genetic data were available, the relation of child saturation to adolescent aggression was moderated by the monoamine oxidase A (MAOA) gene. The regression of aggression on child saturation was steeper for those with the low activity version of the MAOA allele than among those with the high activity version of the allele. The implications of the results for an understanding of the origins and ontogeny of aggression and personality disorders are discussed.

Early life stress, the development of aggression and neuroendocrine and neurobiological correlates: what can we learn from animal models?

Early life stress (child and adolescent abuse, neglect and trauma) induces robust alterations in emotional and social functioning resulting in enhanced risk for the development of psychopathologies such as mood and aggressive disorders. Here, an overview is given on recent findings in primate and rodent models of early life stress, demonstrating that chronic deprivation of early maternal care as well as chronic deprivation of early physical interactions with peers are profound risk factors for the development of inappropriate aggressive behaviors. Alterations in the hypothalamic-pituitary-adrenocortical (HPA), vasopressin and serotonin systems and their relevance for the regulation of aggression are discussed. Data suggest that social deprivation-induced inappropriate forms of aggression are associated with high or low HPA axis (re)activity and a generally lower functioning of the serotonin system in adulthood. Moreover, genetic and epigenetic modifications in HPA and serotonin systems influence the outcome of early life stress and may even moderate adverse effects of early social deprivation on aggression. A more comprehensive study of aggression, neuroendocrine, neurobiological and (epi)genetic correlates of early life stress using animal models is necessary to provide a better understanding of the invasive aggressive deficits observed in humans exposed to child maltreatment.

The 5-HTTLPR polymorphism modulates the association of serious life events (SLE) and impulsivity in patients with Borderline Personality Disorder

BACKGROUND

Impulsivity belongs to the key features of Borderline Personality Disorder (BPD). It has been linked to altered serotoninergic neurotransmission and, genetically, to an over-representation of the short (S) allele of the serotonin transporter promoter-linked polymorphic region polymorphism (5-HTTLPR). On the other hand, serious life events (SLE) are of major importance in the development of BPD. However, the inter-relations between SLEs, impulsivity, and 5-HTTLPR are not understood.

METHOD

159 BPD patients from Germany were included in this study. Impulsivity was assessed by the Barratt Impulsiveness Scale (BIS). We analysed (1) the effects of SLEs on impulsivity; and (2) modulating effects of the 5-HTTLPR polymorphism on the effects of SLEs on impulsivity.

RESULTS

Regression analyses confirmed a decreasing effect of childhood sexual abuse, the cumulative SLE-related reactions and the impairment by SLEs on BIS sum score. Regarding BIS sum score, all SLEs except for rape were associated with a decrease of impulsivity in SS/SL carriers and an increase of BIS sum score in LL carriers.

CONCLUSIONS

This study analyzing a specific gene x environment interaction in BPD patients suggests an interaction between SLEs and the 5-HTTLPR S/L polymorphism in the development of impulsivity in BPD patients. Clinical and research implications are discussed.

Midline brain structures in teenagers with first-presentation borderline personality disorder

Brain morphologic changes have been reported in borderline personality disorder (BPD), but it remains largely unknown whether BPD is associated with midline brain abnormalities. We used magnetic resonance imaging to investigate the length of the adhesio interthalamica (AI) and cavum septum pellucidum (CSP) as well as third ventricular volume in 20 teenagers with first-presentation BPD and 20 healthy controls. While the CSP length did not differ between the groups, the AI was significantly shorter in BPD patients than in controls. Furthermore, the BPD patients had a significantly larger third ventricle than controls. These preliminary findings suggest that ongoing neuroimaging studies should further evaluate a potential involvement of midline brain structures in the pathogenesis of BPD.

Childhood maltreatment and adult personality disorder symptoms: influence of maltreatment type

The present study examines the effects of different types of childhood maltreatment on personality disorder symptoms in a sample of adults with no Axis I psychopathology. Participants reporting a history of moderate to severe maltreatment on the Childhood Trauma Questionnaire (n = 70) were grouped by type of abuse and compared with a non-abused group (n = 35) with regard to the number of personality disorder symptoms endorsed. Physical/sexual abuse and emotional abuse/neglect each were associated with elevated symptoms of all three personality disorder clusters. Elevated symptoms of several specific personality disorders were also seen, including paranoid, borderline, avoidant, dependent, obsessive-compulsive, and depressive personality disorder. There were no significant differences between the maltreatment groups. These findings indicate that emotional abuse/neglect and physical/sexual abuse are risk factors for a broad array of personality outcomes in a non-clinical sample.

Family history of suicidal behavior predicts impulsive-aggressive behavior levels in psychiatric outpatients

OBJECTIVES

Impulsive-aggressive traits have been proposed as mediators of the transmission of suicidal behavior in families. Our aim was to investigate the association between family history of suicidal behavior, and expressions of impulsivity and aggressive behavior, in a clinical population.

METHODS

A sample of n=474 psychiatric outpatient subjects were assessed by means of standardized interviews for Axis I and II psychopathology, history of suicidal behavior in subjects and their family, and measures of impulsive-aggressive behaviors (IAB).

RESULTS

A total of n=38 (8%) probands had a family history of suicidal behavior. This was three times more frequent in patients with a personal history of suicidality, irrespective of their own psychopathology (p<0.001), and four times more frequent in suicide attempters with depression vs. depressed non-attempters (p<0.005). A family history of suicidal behavior was associated with higher impulsive (p<0.005) and aggressive behavior measures (p<0.01) in probands.

LIMITATIONS

Retrospective design and family-history methodology; Limited sample; Contagion and imitation effects could not be assessed based on available data.

CONCLUSIONS

Impulsive-aggressive behaviors are significantly elevated in persons who have a familial loading of suicidal behavior.

A comparison of the family and childhood backgrounds of hospitalised offenders with schizophrenia or personality disorder

BACKGROUND

Previous studies have demonstrated high levels of childhood adversity and familial criminality in offender patients with schizophrenia and/or personality disorder, but few have directly compared these groups.

AIMS

To compare the parenting histories of offender patients with schizophrenia with those with personality disorder. We hypothesised that rates of family criminality and experiences of disrupted parenting would be higher in the personality disorder group than the schizophrenia group.

METHOD

A retrospective case-control methodology compared the family background and childhood experiences of patients with either schizophrenia or personality disorder (n = 3088) admitted to any of the English high-security hospitals.

RESULTS

Compared with those with schizophrenia, patients with personality disorder had experienced higher rates of family criminality, parental separation, and multiple changes of caregiver and institutional care. There was no significant difference in the prevalence of family psychiatric history between the groups.

DISCUSSION

Although our hypotheses were sustained, we were impressed that rates of disruption to parenting were high in the schizophrenia group as well as in the personality disorder group. Less than a third of the personality disorder group had survived childhood without a change in parenting, but this was true for about half of the schizophrenia group, too. Family work tailored for people with schizophrenia is needed, even though within personality disorder services, a greater demand for disorder-sensitive family work is likely to be encountered.

Beyond genetics: childhood affective trauma in bipolar disorder

OBJECTIVES

Despite the demonstrated high heritability of bipolar disorder, few susceptibility genes have been identified and linkage and/or association studies have produced conflicting results. This search for susceptibility genes is hampered by several methodological limitations, and environmental risk factors for the disease (requiring incorporation into analyses) remain misunderstood. Among them, childhood trauma is probably the most promising environmental factor for further investigation. The objectives are to review the arguments in favor of an association between childhood trauma and bipolar disorder and to discuss the interpretations of such an observation.

METHODS

We computed a literature search using PubMed to identify relevant publications concerning childhood trauma and bipolar disorder. We also present some personal data in this field.

RESULTS

Growing evidence suggests that incidences of childhood trauma are frequent and severe in bipolar disorder, probably affect the clinical expression of the disease in terms of suicidal behavior and age at onset, and also have an insidious influence on the affective functioning of patients between episodes. The relationships between childhood trauma and bipolar disorder suggest several interpretations, mainly a causal link, a neurodevelopmental consequence, or the intergenerational transmission of traumatic experiences. The neurobiological consequences of childhood trauma on a maturing brain remain unclear, although such stressors may alter the organization of brain development, leading to inadequate affective regulation.

CONCLUSIONS

Childhood trauma is associated with bipolar disorder and its clinical expression and may interact with genetic susceptibility factors. Although not completely understood, the relationships between childhood trauma and bipolar disorder require further attention. Several suggestions for further exploration of this environmental factor and of its interaction with susceptibility genes are proposed.

Stress load during childhood affects psychopathology in psychiatric patients

BACKGROUND

Childhood stress and trauma have been related to adult psychopathology in different psychiatric disorders. The present study aimed at verifying this relationship for stressful experiences during developmental periods by screening stress load across life in adult psychiatric inpatients with different diagnoses compared to healthy subjects. In addition, a relationship between the amount of adverse experiences and the severity of pathology, which has been described as a 'building block' effect in posttraumatic stress disorder (PTSD), was explored for non-traumatic events in psychiatric disorders other than PTSD.

METHODS

96 patients with diagnoses of Major Depressive Disorder (MDD), schizophrenia, drug addiction, or personality disorders (PD) and 31 subjects without psychiatric diagnosis were screened for adverse experiences in childhood (before the age of six years), before onset of puberty, and in adulthood using the Early Trauma Inventory and the Posttraumatic Stress Diagnostic Scale. Effects of stress load on psychopathology were examined for affective symptoms, PTSD, and severity of illness by regression analyses and comparison of subgroups with high and low stress load.

RESULTS

High stress load in childhood and before puberty, but not in adulthood, was related to negative affect in all participants. In patients, high stress load was related to depressive and posttraumatic symptoms, severity of disorder, and the diagnoses of MDD and PD.

CONCLUSION

Results support the hypothesis of stress-sensitive periods during development, which may interact with genetic and other vulnerability factors in their influence on the progress of psychiatric disorders. A 'dose' effect of stress load on the severity of psychopathology is not restricted to the relationship between traumata and PTSD.

Familial clustering of suicidal behaviour and psychopathology in young suicide attempters. A register-based nested case control study

INTRODUCTION

Familial clustering of suicidal behaviour and psychopathology has been reported in young suicide attempters. Most of these studies were predominantly carried out in clinical treatment settings and lacked statistical power to assess the independent and modifying influences of own and familial psychopathology and suicidal behaviour.

METHODS

We carried out a population-based record-linkage study with a nested case control design. The 14,440 individuals hospitalised due to suicide attempt (cases) and 144,400 matched controls were born in Sweden between 1968 and 1980 and followed up till December 31, 1999.

RESULTS

Among the strongest independent familial risk factors for youth suicide attempt were siblings' (OR 3.4; 2.8-4.1), maternal (OR 2.7; 2.5-3.1) and paternal (OR 1.9; 1.7-2.1) suicide attempt. Other important risk factors were familial personality and substance abuse disorders, maternal schizophrenia, non-affective psychoses and organic disorders and parental neurotic, stress-related and somatoform disorders (1.9-3.2 fold increase), and paternal (OR 1.9; 1.6-2.3) and maternal (OR 1.8; 1.3-2.4) suicide completion. Mental illnesses in index subjects, particularly substance abuse, affective and personality disorders, were the dominant determinants of suicide attempt. Strong interactions were observed between psychopathology in index subjects and familial suicidality. Familial suicide completion had a stronger effect on suicide attempt of earlier onset and on boys. Nearly half (47%) of all suicide attempts could be attributed to familial psychopathology (13%), family suicide attempt (7%) and suicide completion (1%) and own psychopathology (25%).

CONCLUSION

Early recognition and adequate treatment of individual mental illness contribute to prevent youth suicide attempts. Children of parents with psychopathology and suicidal behaviour should receive early support and attention. Evaluation of familial suicidal behaviour seems to be vital for suicide risk assessment in young psychiatric inpatients. There appears to be an independent effect of familial suicidal behaviour as well as familial psychopathology on youth suicide attempt beyond the transmission of mental illness.

CSF corticotropin-releasing factor in personality disorder: relationship with self-reported parental care

This cross-sectional investigation tests the relationship between the level of self-reported childhood parental care and cerebrospinal fluid (CSF) corticotropin-releasing factor (CRF) concentration in adults with and without personality disorder (PD). Based on preclinical models of the lasting effect of post-natal parental care on central CRF function, the primary hypothesis was that childhood parental care, as reflected by the parental bonding inventory (PBI) care and involvement subscale, is inversely correlated with adult CSF CRF levels. The sample includes cerebrospinal fluid CRF samples from 19 subjects who were included in a previously published report on the relationship between CRF level and Childhood Trauma Questionnaire score. Parental bonding was measured retrospectively with the PBI in 54 medication-free male and female subjects, 37 of whom were diagnosed with a DSM-IV PD, 17 of whom were normal controls free of Axis I and II psychopathology. CSF CRF level as measured by lumbar puncture was entered into a model as the dependent variable, with the independent variables of PBI Parental Care and Involvement, diagnostic category, age, and gender. The model predicting CSF CRF level was significant, with PBI parental care and involvement negatively correlated with CSF CRF level. PD subjects with higher than median PBI parental care and involvement score had significantly lower CSF CRF levels than both normal controls and PD subjects with lower than median PBI parental care and involvement. Higher levels of self-report parental care predict lower CSF CRF levels in PD subjects, consistent with a beneficial effect of parental care on decreased stress reactivity, and consistent with previous reports in humans. The cross-sectional design of the study, however, limits causal inferences.

Exposure to early life trauma is associated with adult obesity

Exposure to traumatic events during childhood is associated with an elevated risk of adult obesity. It has been hypothesized that the psychological sequelae from childhood trauma account for this risk, though no study has examined whether an increased risk of obesity is found in persons without psychological disorders. We examined exposure to early life stressors and body mass index (BMI) in 696 adults without significant medical or psychiatric history. Bivariate correlation showed that the total number of early life stressors (r=0.08), age (r=0.19), and sex (r=0.16) were significantly related to adult BMI. Given the relationship between sex and BMI, we examined the contribution of early life stressors to adult obesity separately for men and women. In men, hierarchical regression showed that exposure to early life stressors predicted adult obesity. Specifically, history of being bullied/rejected (Obese 31%, Normal weight, 9%) and emotional abuse (Obese, 17%; Normal weight, 2%) predicted adult obesity after controlling for the effects of age. In women, no relationship between early life stressors and adult obesity was found. These findings suggest that multiple processes mediate the relationship between early life stress and adult obesity and that their relative contributions may differ between men and women.

Dissoziale Persönlichkeitsstörung

Deviant behavior is gaining in clinical importance if it is founded on stable, characteristic, and enduring patterns of psychopathologically relevant personality traits which have their onset in childhood or adolescence. The classification of these traits shows variations, so that a distinction between the ICD-10 diagnosis of dis-social personality disorder, DSM-IV diagnosis of antisocial personality disorder, and the concept "psychopathy" is necessary. Our knowledge about the biological basis of antisocial behavior includes neurophysiologic, psychophysiologic, and genetic findings. Also relevant are results of neurotransmitter studies and structural resp. functional neuroimaging findings. Psychosocial risk factors include parental deficits, rejection, disregard, unstable relations, and abuse. Efficient psychotherapeutic treatment is cognitive-behavioral. Pharmacologic treatment is largely "off-label". The diagnosis of antisocial and dis-social personality disorders allows no conclusions on criminal responsibility. In addition to psychiatric diagnostics, considerations on the severity of the disorder and its effects on the ability to inhibit actions are necessary.

Childhood trauma and personality disorder: toward a biological model

Cross-sectional and prospective associations of personality disorder with childhood trauma provide an important clue regarding the biological mechanism of personality disorder. In this review, empirical literature from several domains is summarized. These include relevant findings from behavioral genetics, preclinical models of early life parental care, and clinical translational studies of personality disorder. Identification of the biological mechanism by which childhood trauma exerts an effect on personality disorder may require modification of the conceptualization of personality disorder, either as a set of categories or dimensions.