Genetics of personality disorders

Early maladaptive schema, attachment style, and parenting style in a clinical population with personality disorder and normal individuals: a discriminant analysis model

INTRODUCTION

Researchers have shown various variables' role in forming personality disorders (PD). This study aimed to assess the role of early maladaptive schema (EMS), attachment style (AS), and parenting style (PS) in discriminating between personality disorders and normal individuals.

METHODS

In this study, 78 personality disorder patients and 360 healthy volunteers aged 18-84 were selected using convenience sampling. They completed the Schema Questionnaire-Short Form (SQ-SF), Revised Adult Attachment Scale (RAAS), and Baumrind's Parenting Styles Questionnaire (PSI). Data were analyzed using discriminant analysis with IBM SPSS 25.

RESULTS

The results showed higher mean scores in all early maladaptive schema domains, insecure attachment styles, and authoritarian parenting in the personality disorder group than in the normal group. Also, discriminant analyses revealed that the function was statistically significant and could distinguish between the two groups and a compound of essential variables, disconnection, impaired autonomy, and secure attachment, respectively, discriminating two groups. Given that all components were able to distinguish between the two groups.

CONCLUSION

Therefore, intervention based on these factors early in life may help reduce the characteristics of personality disorders. Also, considering the role of these factors, treatment protocols can be prepared.

The structure of genetic and environmental influences on normative personality, abnormal personality traits, and personality disorder symptoms

BACKGROUND

Can the structure of genetic and environmental influences on normative personality traits (NPTs), abnormal personality traits (APTs), and DSM-IV criteria for personality disorders (PD) fit a high or low congruence model positing, respectively, close or more limited etiologic continuity?

METHOD

Exploratory factor analysis was applied to transformed correlation matrices from Cholesky twin decompositions obtained in OpenMx. In 2801 adult twins from the Norwegian Institute of Public Health Twin Panel, NPTs and APTs were assessed by self-report using the Big Five Inventory (BFI) and PID-5-Norwegian Brief Form (PID-5-NBF), respectively. PDs were assessed at interview using the Structured Interview for DSM-IV Personality (SIDP-IV).

RESULTS

The best model yielded three genetic and three unique environmental factors. Genetic factors were dominated, respectively, by (i) high loadings on nearly all PDs and NPT/APT neuroticism and compulsivity, (ii) negative loadings on NPT agreeableness/conscientiousness and positive loadings on APT/PD measures of antisocial traits, and (iii) negative loadings on NPT extraversion and histrionic PD, and positive loadings on APT detachment and schizoid/avoidant PD. Unique environmental factors were dominated, by (i) high loadings on all PDs, (ii) high loadings on all APT dimensions and NPT neuroticism, and (iii) negative loadings on NPT extraversion and positive loadings on NPT detachment/avoidant PD.

CONCLUSIONS

Two genetic and one environmental common factor were consistent with a high congruence model while one genetic and two environmental factors were more supportive of a low congruence model. The relationship between genetic and environmental influences on personality assessed by NPTs, APTs, and PDs is complex and does not fit easily into a low or high congruence model.

Do DSM-5 Section II personality disorders and Section III personality trait domains reflect the same genetic and environmental risk factors?

BACKGROUND

DSM-5 includes two conceptualizations of personality disorders (PDs). The classification in Section II is identical to the one found in DSM-IV, and includes 10 categorical PDs. The Alternative Model (Section III) includes criteria for dimensional measures of maladaptive personality traits organized into five domains. The degree to which the two conceptualizations reflect the same etiological factors is not known.

METHODS

We use data from a large population-based sample of adult twins from the Norwegian Institute of Public Health Twin Panel on interview-based DSM-IV PDs and a short self-report inventory that indexes the five domains of the DSM-5 Alternative Model plus a domain explicitly targeting compulsivity. Schizotypal, Paranoid, Antisocial, Borderline, Avoidant, and Obsessive-compulsive PDs were assessed at the same time as the maladaptive personality traits and 10 years previously. Schizoid, Histrionic, Narcissistic, and Dependent PDs were only assessed at the first interview. Biometric models were used to estimate overlap in genetic and environmental risk factors.

RESULTS

When measured concurrently, there was 100% genetic overlap between the maladaptive trait domains and Paranoid, Schizotypal, Antisocial, Borderline, and Avoidant PDs. For OCPD, 43% of the genetic variance was shared with the domains. Genetic correlations between the individual domains and PDs ranged from +0.21 to +0.91.

CONCLUSION

The pathological personality trait domains, which are part of the Alternative Model for classification of PDs in DSM-5 Section III, appears to tap, at an aggregate level, the same genetic risk factors as the DSM-5 Section II classification for most of the PDs.

The association between personality disorders with alcohol use and misuse: A population-based twin study

BACKGROUND

A clearer understanding of the etiological overlap between DSM-IV personality disorders (PDs) and alcohol use (AU) and alcohol use disorder (AUD) is needed. To our knowledge, no study has modeled the association between all 10 DSM-IV PDs and lifetime AU and AUD. The aim of the present study is to identify which PDs are most strongly associated with the phenotypic, genetic, and environmental risks of lifetime AU and AUD, and to determine if these associations are stable across time.

METHODS

Participants were Norwegian twins assessed at two waves. At Wave 1, 2801 twins were assessed for all 10 DSM-IV PD criteria, lifetime AU, and DSM-IV AUD criteria. At Wave 2, six of the 10 PDs were again assessed along with AU and AUD among 2393 twins. Univariate and multiple logistic regressions were run. Significant predictors were further analyzed using bivariate twin Cholesky decompositions.

RESULTS

Borderline and antisocial PD criteria were the strongest predictors of AU and AUD across the two waves. Despite moderate phenotypic and genetic correlations, genetic variation in these PD criteria explained only 4% and 3% of the risks in AU, and 5% to 10% of the risks in AUD criteria, respectively. At Wave 2, these estimates increased to 8% and 23% for AU, and 17% and 33% for AUD.

CONCLUSIONS

Among a large Norwegian twin sample, borderline and antisocial PD criteria were the strongest predictors of the phenotypic and genotypic liability to AU and AUD. This effect remained consistent across time.

Personality disorders in adopted versus non-adopted adults

The goal of this epidemiological study was to investigate lifetime history and odds ratios of personality disorders in adopted and non-adopted adults using a nationally representative sample. Data, drawn from the National Epidemiological Survey on Alcohol and Related Conditions (NESARC), were compared in adopted (n=378) versus non-adopted (n=42,503) adults to estimate the odds of seven personality disorders using logistic regression analyses. The seven personality disorders were histrionic, antisocial, avoidant, paranoid, schizoid, obsessive-compulsive, and dependent personality disorder. Adoptees had a 1.81-fold increase in the odds of any personality disorder compared with non-adoptees. Adoptees had increased odds of histrionic, antisocial, avoidant, paranoid, schizoid, and obsessive-compulsive personality disorder compared with non-adoptees. Two risk factors associated with lifetime history of a personality disorder in adoptees compared to non-adoptees were (1) being in the age cohort 18-29 years (but no difference in the age 30-44 cohort), using the age 45 or older cohort as the reference and (2) having 12 years of education (but no difference in higher education groups), using the 0-11 years of education as the reference. These findings support the higher rates of personality disorders among adoptees compared to non-adoptees.

Testing different versions of the Affective Neuroscience Personality Scales in a clinical sample

Background

As a tool to investigate the experiences of six primary emotions, Davis, Panksepp, and Normansell [1] developed the Affective Neuroscience Personality Scales (ANPS). However, the psychometric properties of the ANPS have been questioned, and in particular the factor structure. This study replicates earlier psychometric studies on ANPS in a sample of (546) personality disordered patients, and also includes ANPS-S, a recent short version of ANPS by Pingault and colleagues [2], and a truncated version of BANPS by Barrett and colleagues [3].

Methodology/Principal Findings

The study of the full ANPS revealed acceptable internal consistencies of the primary emotion subscales, ranging from 0.74–0.87. However, factor analyses revealed poor to mediocre fit for a six factor solution. Correlational analyses, in addition, revealed too high correlations between PLAY and SEEK, and between SADNESS and FEAR. The two short versions displayed better psychometric properties. The range of internal consistency was 0.61–0.80 for the BANPS scales and 0.65–84 for the ANPS-S. Backward Cronbach Alpha Curves indicated potentials for improvement on all three versions of the questionnaire. Items retained in the short versions did not systematically cover the full theoretical content of the long scales, in particular for CARE and SADNESS in the BANPS. The major problems seem to reside in the operationalization of the CARE and SADNESS subscales of ANPS.

Conclusions/Significance

Further work needs to be done in order to realize a psychometrically sound instrument for the assessment of primary emotional experiences.

Paranoid personality disorder

Paranoid personality disorder (PPD) is currently included in DSM-IV's "odd cluster" or "cluster A." In the present article, the authors review available information pertaining to the psychometric properties of PPD, as derived from the relevant literature and from databases of personality disorder study groups. There is comparatively little published evidence for the reliability and validity of PPD, and researchers by and large have tended not to study the disorder, either because of investigators' difficulty recruiting individuals with PPD into research studies, or (as seems more likely) because the trait-paranoia from which many psychiatric patients suffer has seemed better explained by other DSM-IV disorders on Axis I and/or Axis II than by PPD. Given the scant empirical evidence on PPD, it seems reasonable to remove it as an independent diagnosis from the next edition of DSM, and instead to encourage clinicians to code trait-paranoia using a dimensional approach.

New directions for an old construct: Depressive personality research in the DSM-5 era

The DSM-5 Personality and Personality Disorders Work Group has suggested that the DSM-IV depressive personality disorder (DPD) construct be assessed within a proposed set of trait domains, which include anxiousness, depressivity, and anhedonia, and that the diagnostic category itself be removed from the DSM-5. A review of studies on DPD has demonstrated many challenges and limitations to DPD research, despite strong evidence of its validity and clinical utility. Nevertheless, there remains much interest in how a depressive personality construct fits into a dimensionalized framework of assessing psychopathology. In this paper, I offer three major research directions that can help advance our understanding of the depressive personality construct. These directions can inform researchers and clinicians how depressive personality fits within broad trait dimensions of classification, as well as the internal psychological processes, dynamics and content that characterize this type of psychopathology.

A Five-Factor Model framework for understanding childhood personality disorder antecedents

The present contribution reviews evidence that supports the relevance of childhood antecedents of personality disorders, and advocates that the validity of a Five-Factor Model framework for describing general trait differences in childhood can be extended towards the field of developmental personality difficulties. In addition, we suggest that several traditional childhood Axis I conditions include a substantial trait component that may be responsible for the recurring finding that childhood Axis I disorders are predictive for adult Axis II disorders. Given the valuable information provided by a trait assessment, we further propose to integrate dimensional personality and personality pathology measures as standard tools in mental health assessments at a young age.

Mental health of African Americans and Caribbean blacks in the United States: results from the National Epidemiological Survey on Alcohol and Related Conditions

OBJECTIVES

Previous epidemiological studies have found lower mood, anxiety, and substance use disorder prevalence in Black Americans, in general, compared with White Americans. We estimated the prevalence and persistence of psychiatric disorders in African Americans, Caribbean Blacks, and non-Hispanic Whites.

METHODS

We drew data from wave 1 (2001-2002) of the National Epidemiological Survey of Alcohol and Related Conditions, a nationally representative sample of US adults, which included 7529 African Americans, 469 Caribbean Blacks, and 24 502 non-Hispanic Whites.

RESULTS

Blacks had equal or lower prevalence than Whites of lifetime (adjusted odds ratio [AOR] =0.6 for African Americans; 0.3 for Caribbean Blacks) and 12-month (AOR =0.7 for African Americans; 0.4 for Caribbean Blacks) Axis I psychiatric disorders, but higher prevalence of several personality disorders. Among Blacks, Caribbean Blacks had higher prevalence of 12-month psychotic disorders and lower lifetime prevalence of major depressive disorder, alcohol dependence, and drug abuse than African Americans. There were no differences in persistence of disorders between Caribbean Blacks and African Americans.

CONCLUSIONS

This study yielded new data on prevalence of mental disorders in these groups, which has important implications for clinical work with US Blacks.

Schizoid personality disorder

Schizoid personality disorder (ScPD) is one of the "odd cluster" or "cluster A" personality disorders in DSM-IV. In the present article, the authors review information pertaining to the psychometric characteristics of ScPD as gleaned from a search of relevant publications as well as from databases of personality disorder study groups. Comparatively little evidence exists for the validity and reliability of ScPD as a separate, multifaceted personality disorder. Some authors, moreover, have contended that the group of patients termed "schizoid" actually fall into two distinct groups--an "affect constricted" group, who might better be subsumed within schizotypal personality disorder, and a "seclusive" group, who might better be subsumed within avoidant personality disorder. The research-based justification for retaining ScPD as an independent diagnosis is sufficiently sparse for it to seem reasonable to remove ScPD from the list of personality disorders in DSM-V, and instead to invite clinicians to code for schizoid traits using a dimensional model.

Integrating normal and abnormal personality structure: a proposal for DSM-V

The personality disorders section of the American Psychiatric Association's fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) is currently being developed. The purpose of the current paper is to encourage the authors of DSM-V to integrate normal and abnormal personality structure within a common, integrative model, and to suggest that the optimal choice for such an integration would be the five-factor model (FFM) of general personality structure. A proposal for the classification of personality disorder from the perspective of the FFM is provided. Discussed as well are implications and issues associated with an FFM of personality disorder, including validity, coverage, feasibility, clinical utility, and treatment implications.

Personality disorders: epidemiology and public health issues

Community studies conducted over the past decade have greatly increased our knowledge of the epidemiology of personality disorders. Here, we review the prevalence, distribution, and consequences of personality disorders, and potential risk factors for their development. An estimated 6-10% of individuals in the community have a personality disorder. The prevalence of personality disorders varies across sociodemographic groups, being higher, for example, in those who are separated or divorced and those who have dropped out of high school. Personality disorders are strongly associated with Axis I disorders in the community, including mood disorders, anxiety disorders, and alcohol and other substance use disorders, as well as with functional impairment. Personality disorders also are associated with medical service use and medical morbidity and mortality, especially related to cardiovascular disease. Individuals in the community with personality disorders are more likely to have a history of criminal arrest, interpersonal violence, and suicidal behaviours. Childhood adversities, especially abuse and neglect, are potential risk factors for the development of personality disorders. Additional prospective studies are needed to elucidate potential precursors and consequences of personality disorders. Furthermore, primary and secondary prevention strategies are needed to reduce the individual and societal burdens from personality disorders in the community.

Association between 5-HTTLPR and Borderline Personality Disorder Traits among Youth

This study provides the first genetic association examination of borderline personality disorder (BPD) traits in children and adolescents (ages 9-15) using two independent samples of youth recruited from the general community. We tested the a priori hypothesis that the serotonin transporter promoter gene (5-HTTLPR) would relate specifically to BPD traits in youth. This association was hypothesized based on prior genetic association research with BPD adults and theory positing that emotion dysregulation may be a core risk process contributing to BPD. Youth provided DNA via buccal cells. Both youth and a parent completed self-report measures assessing youth's BPD traits and depressive symptoms. Results from both Study 1 (N = 242) and an independent replication sample of Study 2 (N = 144) showed that carriers of the short allele of 5-HTTLPR exhibited the highest levels of BPD traits. This relation was observed even after controlling for the substantial co-occurrence between BPD traits and depressive symptoms. This specific association between 5-HTTLPR and BPD traits among youth supports previous genetic associations with adults diagnosed with BPD and provides preliminary support for a developmental extension of etiological risk for BPD among youth.

Gene-environment interaction of child temperament

OBJECTIVE

The aims of this study were to review studies on the molecular genetics of child temperament and prospectively analyze infant temperament as a function of the interaction between infant and mother: 5-HTT, DRD4, and MAO-A functional polymorphisms and the mother's emotional state.

METHOD

A prospective study of 317 newborns and their mothers was performed. Infant temperament and the mother's anxiety and confidence in caregiving were evaluated at 8 and 32 weeks after childbirth using the Mother and Baby Scale. The mother's emotional state was evaluated using the Edinburgh Postpartum Depression Scale and the State-Trait Anxiety Inventory. These variables were correlated with 5-HTTLPR and Stin2 variants in the 5-HTT gene and the DRD4 variable number tandem repeats Exon 3 and MAO-A variable number tandem repeats genotypes of both the infants and their mothers.

RESULTS

The irritability scores of infants with the 5-HTTLPR s allele showed a linear relationship with their mothers' anxiety of caregiving at 8 (p = .011) and 32 weeks (p = .001), whereas the irritability of infants carrying the HTTLPR ll genotype was independent of their mothers' anxiety.

CONCLUSIONS

The review of the literature in this field and the results of this study support that the 5-HTTLPR polymorphism moderates the influence of the mother's anxiety on infant irritability.

The genetic epidemiology of personality disorders

Genetic epidemiologic studies indicate that all ten personality disorders (PDs) classified on the DSM-IV axis II are modestly to moderately heritable. Shared environmental and nonadditive genetic factors are of minor or no importance. No sex differences have been identified. Multivariate studies suggest that the extensive comorbidity between the PDs can be explained by three common genetic and environmental risk factors. The genetic factors do not reflect the DSM-IV cluster structure, but rather: i) broad vulnerability to PD pathology or negative emotionality; ii) high impulsivity/low agreeableness; and iii) introversion. Common genetic and environmental liability factors contribute to comorbidity between pairs or clusters of axis I and axis II disorders. Molecular genetic studies of PDs, mostly candidate gene association studies, indicate that genes linked to neurotransmitter pathways, especially in the serotonergic and dopaminergic systems, are involved. Future studies, using newer methods like genome-wide association, might take advantage of the use of endophenotypes.

Two models of suicide

Objective: The aim of this paper is to present two models of separate but related aspects of suicide, developed with a view to improving understanding and management of this behaviour. Conclusions: First, the predicament model of suicide posits that all suicide represents an escape from a predicament and associated distress. Predicaments are composed of either external (environmental) or internal (mental disorders) factors, or both. Suicide occurs when a threshold is exceeded on a suicide risk ladder, and the degree of movement toward the threshold in response to a particular stressor depends on a range of factors. Second, the suicide pathways model integrates medical and sociological concepts, with distress as the central component, and three run-offs: mental disorder, medicalized and a non-mental disorder (egoistic/anomic; reaction) suicide.

Childhood personality pathology: dimensional stability and change

Studies on the developmental course of personality disorders have suggested that adult personality disorders enclose both features with a natural plasticity over time, as well as stable components represented by underlying trait dimensions. The current study broadens this dimensional stability perspective toward an earlier developmental stage, and describes with different indices of stability the longitudinal behavior of basic childhood maladaptive trait dimensions in a community sample of 477 Flemish children. The results underscore structural, rank-order, and within-person stability for the disagreeableness, emotional instability, introversion, and compulsivity dimensions and suggest a similar maturation principle as has been proposed for adults. Individual growth curve analyses indicate that children's maladaptive trait scores generally decrease as they grow older, with a smaller decline for high-scoring individuals. Childhood maladaptive traits and general psychopathology dimensions show similar longitudinal patterns in terms of shape and change over time, supporting a spectrum conceptualization of Axis I related pathology and personality disorder precursors at young age. The implications of these findings for a developmental perspective on dimensional conceptualizations of personality disorders are discussed.

[Neuroethics in clinical practice]

In recent years the ability of neuroscience to identify and intervene in mental functions has progressed immensely, which raises several anthropologic and ethical questions. Meanwhile neuroethics arose as a new interdisciplinary field for critical analysis of neuroscientific actions and ethical reflection on the increasing knowledge of the human brain, with regard to society and politics. This article provides a survey of neuroethical implications for clinical practice.

The treatment of borderline personality disorder: implications of research on diagnosis, etiology, and outcome

The treatment of patients with borderline personality disorder (BPD) is challenging. Making a diagnosis is necessary to plan therapy. But since we do not know the etiology of BPD, treatment cannot be based on a well-established theory. Outcome research shows that most patients recover with time. A series of clinical trials show that a variety of psychotherapies are effective in BPD and that the effects of medication are unimpressive.

The structure of genetic and environmental risk factors for DSM-IV personality disorders: a multivariate twin study

CONTEXT

Although both genetic and environmental factors affect risk of individual personality disorders (PDs), we know little of how they contribute to the pattern of comorbidity between the PDs in the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) (DSM-IV).

OBJECTIVE

To clarify the structure of the genetic and environmental risk factors for the 10 DSM-IV PDs.

DESIGN

Assessment of PDs at personal interview and multivariate twin modeling with the Mx program.

SETTING

General community.

PARTICIPANTS

A total of 2794 young adult members of the Norwegian Institute of Public Health Twin Panel. Main Outcome Measure Number of endorsed criteria for the 10 DSM-IV PDs.

RESULTS

The best-fit multivariate twin model required 3 genetic and 3 individual-specific environmental factors and genetic and individual-specific factors unique to each PD. The first genetic factor had high loadings on PDs from all 3 clusters including paranoid, histrionic, borderline, narcissistic, dependent, and obsessive-compulsive. The second genetic factor had substantial loadings only on borderline and antisocial PD. The third genetic factor had high loadings only on schizoid and avoidant PD. Several PDs had substantial disorder-specific genetic risk factors. The first, second, and third individual-specific environmental factors had high loadings on the cluster B, A, and C PDs, respectively, with 1 exception: obsessive-compulsive PD loaded with cluster B and not cluster C PDs.

CONCLUSIONS

Genetic risk factors for DSM-IV PDs do not reflect the cluster A, B, and C typology. Rather, 1 genetic factor reflects a broad vulnerability to PD pathology and/or negative emotionality. The 2 other genetic factors are more specific and reflect high impulsivity/low agreeableness and introversion. Unexpectedly, the cluster A, B, and C typology is well reflected in the structure of environmental risk factors, suggesting that environmental experiences may be responsible for the tendency of cluster A, B, and C PDs to co-occur.