Personality disorders II

Question 1

prevalence of PDs

Answer 1

Prevalence estimates for Personality Disorders vary considerably across studies (for reviews see Coid et al., 2006; Torgersen et.al., 2001 and Weissman, 1993).
- Coid et al. (2006) used large sample

Personality disorders are relatively common and general estimates indicate that they affect around 10-13% of the general population (Weissman, 1993).

• Can be distressing to be labelled
• In the general population, schizotypal, histrionic, dependent and obsessive-compulsive personality disorders are the most common.
• Narcissistic personality disorder is the rarest – approximately 0.2% in the general population

Question 2

Coid et al. (2006)

Answer 2

reviewed prevalence rates of PDs and report a range of 3.9% to 22.3%.

• The prevalence rates for PDs in a British population were 4.4% – this is relatively low compared with many previous studies.
• Participants with any personality disorder were more likely to be male, older, separated or divorced, unemployed or economically inactive, of lower social class, living in rented accommodation and living in an urban area – can be consequence of disorder rather than causing it
• Noted gender differences
• Correlational data

Those with cluster A disorders were three times more likely to have been in local authority care before the age of 16 years

• Foster care
• Neglect or abuse before foster care

Those with cluster B disorders were more likely to have had a criminal conviction, to have spent time in prison and have been in local authority or institutional care – poor backgrounds

Those with cluster C disorders were more likely to have received psychotropic medication and/or counselling

Question 3

gender differences in personality traits

Answer 3

Gender differences in personality appear in childhood and are stable over time (for an overview see Paris 2007)
- Young girls more skilled at overcoming and hiding issues – female autistic children less likely to be diagnosed than males – better at developing coping skills

A meta-analysis by Feingold (1994)

Goodwin and Gotlib (2004)

While socialization theories are influential in explaining these variations, gender differences in personality are also rooted in biology.

Personality disorders can be understood as dysfunctional exaggerations of normal personality traits (e.g., Livesley, Jang, & Vernon, 1998).

The most striking difference is the higher prevalence of antisocial personality disorder in men (Black, 1999), with 80% of cases of antisocial personality being men.

The personality trait that underlies antisocial personality disorder (ASPD) has been termed impulsive aggression (Siever & Davis, 1991), a characteristic more commonly found in males.

Question 4

Feingold (1994)

Answer 4

males were more assertive and have higher self-esteem (has been replicated in the literature), while females were higher in extraversion (less common finding), anxiety, trust and nurturance

Question 5

Goodwin and Gotlib (2004)

Answer 5

studied the Five Factor Model of Personality in a large community sample - neuroticism, agreeableness, conscientiousness and extraversion were all higher in women, while open-ness to experience was higher in men.

Question 6

costa, terracciano and McCrae (2001)

Answer 6

found that while gender differences can be exaggerated or reduced by cultural forces, similar gender effects on traits are seen in cultures all over the world.
- This shows that gender differences on personality, while they may be reinforced by socialization, are not entirely socially constructed – something else going on because of universal nature

Question 7

Gender differences in the prevalence of PDs

Answer 7

vary across studies but tend to be higher for men (Coid et al., 2006):

• Men were more likely to have a disorder (5.4%) compared with women (3.4%).
• The prevalence of antisocial personality disorder was five times greater in men (1.0%) than in women (0.2%).
• Oltmanns & Emery, (2004), also provide evidence showing a strong tendency for Antisocial Personality Disorder to be more prevalent in men (4.5%) than women (0.8%).
• All personality disorder categories were more prevalent in men, apart from the schizotypal category.

Question 8

possible gender biases in diagnosis

Answer 8

Criteria defining a disorder might derive from particular gender stereotypes and this can affect diagnosis.

Possible gender differences in manifestation of symptoms of different disorders (e.g., attention seeking – hyperfeminity/hypermasculinity).

Criteria for diagnosis of APSD includes a prior history of conduct disorder (more prevalent among boys/males). Aggressiveness and a pattern of criminal behaviour (both more common in men)

Question 9

diagnosis can be controversial

Answer 9

Several flaws in the prevailing system of diagnosis help explain inaccuracies in estimating the overall prevalence rate for PD.

• Co-morbidity – most people with a diagnosable disorder typically have two or more disorders.
  
  • Research suggests co-morbidity is normative with personality disorders.
  • If a person meets the criteria for one personality disorder there is a 25-50% probability that they will also meet criteria for a second personality disorder (e.g., Oltmanns & Emery, 2004).

Question 10

prevalence and co-morbidity

Answer 10

Coid et al (2006) – co-morbidity of personality disorders

• The mean number of personality disorder diagnoses among those who qualified for such a diagnosis was 1.92; of these,
  
  • 53.5% had one disorder only
  • 21.6% had two disorders
  • 11.4% had three disorders
  • 14.0% had between four and eight diagnoses
• Classification of personality disorder by cluster showed
  
  • Cluster C to be the most frequent (2.6%)
  • Cluster A (1.6%)
  • Cluster B (1.2%) least prevalent.

Question 11

diagnosis and comorbidity

Answer 11

Co-morbidity of personality disorders occurs in part because the categories are imprecisely defined and they have overlap.

• Many of the PDs share common features: e.g., social isolation is involved in various disorders including schizotypal, schizoid and avoidant.
• Some PDs share common features with clinical conditions also detailed in DSM-V – social phobia and avoidant PD).

Co-morbidity undermines the categorical approach and points instead to a dimensional approach in which people can be characterised according to scores on several personality dimensions.
- Problems due to categorical approach

Question 12

development of PDs

Answer 12

The pervasive nature of personality disorders and the fact that they are resistant to change by interventions has led to the use of the terms ‘development’ and ‘management’ rather than ‘aetiology’ and ‘treatment’ (Holmes, 2010).
- Ideas around treatment side are changing

Personality disorders begin to be evident in childhood and early adolescence and persist through adulthood.

• This indicates possible genetic predispositions but traditional explanations have highlighted early disturbances of development – e.g., maternal deprivation, abuse, disruptive childhood – could occur in school as well
• Parents might be reacting to pre-existing challenging behaviours, which might be early manifestations of personality problems.
  
  • Supported by evidence showing siblings who experienced similar parenting do not exhibit such profound personality distortions.
  • Don’t want to label the child too early

Environmental, genetic and biological factors influence the development of personality disorders.

• Note of caution:
  
  • most of the research examining personality disorders is correlational not experimental. Therefore, the direction of causality is not known.

Biological, genetic and environmental factors are highly intermingled making it extremely difficult to establish one particular cause of a disorder.
- Human personality both normal and disordered has multiple causes.

Question 13

biological influences

Answer 13

Various biological and neuropsychological factors have been associated with personality disorders.

• E.g., particularly high or low levels of neurotransmitters dopamine and serotonin have been related to each of the three clusters of personality disorders.
• But it is not known if it’s the level of a neurotransmitter that causes the personality disorder or whether having the disorder causes the high/low level of the neurotransmitter.
• Traumatic brain injury – ‘Phineas Gage’ is an example of an abrupt personality change following neurological damage.
  
  • Suffered severe damage to frontal lobes and developed marked anti-social traits.
  • Dysfunction due to brain being injured
• Williams, Mewse et al.

Question 14

biological influences - Siever and Davis (1991)

Answer 14

propose a neuropsychological model illustrating four psychological pathways through which neurotransmitters might influence personality disorder clusters:

1. cognitive/perceptual processes (two of the remaining lectures will be focussed on these processes).
2. impulsivity/aggression
3. affect regulation
4. anxiety/inhibition

Question 15

genetic influences

Answer 15

Two studies that have used heritability estimates (can be problematic) to examine genetic influences on all personality disorders indicate quite substantial genetic components:

• Torgersen et al., (2001) (adult DZ and MZ twins) present heritability estimates for each of the 12 personality disorders individually as well as by cluster.
  
  • Heritability estimates for Personality Disorders: Cluster A = 0.37, Cluster B = 0.60, Cluster C = 0.62
• Coolidge et al., 2001 (children aged 4 – 15 years, DZ and MZ twins).
  
  • Heritability estimates for each of the twelve personality disorders ranged from 0.81 - 0.50 with an average heritability coefficient across the disorders of 0.75.
• These heritability estimates suggest that genetic influences on personality disorder show a range similar to those estimated for normal personality.

The same problems surround heritability estimates of disordered personality as those described in earlier lectures concerning heritability estimates and normal personality / intelligence.

Question 16

environmental influences

Answer 16

Developmental and childhood experiences have been shown to be important factors associated with Antisocial (APD) and Borderline Personality Disorders (BPD).

• Childhood factors including abuse (emotional, physical or sexual), neglect, unstable home environment and low levels of nurturing are strongly implicated in the development of APD and BPD (e.g., Johnson et al., 2006; Helgeland & Torgersen, 2004).
• The development of schizotypal personality disorder traits is also influenced by abuse and neglect in childhood (e.g., Anglina et al., 2008).
• A study of male college students found that histories of childhood (sexual and/or physical) abuse were significantly associated with higher levels of symptomology across each of the Personality Disorder clusters A, B and C (see Miller & Lisak, 1999).

Question 17

PDs and personal trait theory

Answer 17

The Five-Factor Model and personality disorders (measured by the NEO-PI-R).

• Costa and McCrae (1992a, 1992b) - the five-factor model is highly relevant to both the conceptualisation and assessment of personality disorders.
  
  • E.g., High neuroticism linked with paranoia and borderline personality disorder symptoms as well as with depression and anxiety-related disorders.
  • E.g., Low agreeableness was associated with paranoia, schizophrenia and features of borderline and anti-social personality disorders.
• The six facets that comprise each of the five factors are particularly useful in distinguishing between the different personality disorders.
• Clinical assessment of the traits that comprise each of the five superfactors has the benefit of providing a comprehensive overview of personality structure and highlights potential avenues for treatment.

Associations between facets of the five superfactors and the Personality Disorder Clusters show clear differences exist within and between Clusters.
- This indicates the Five-Factor Model can be useful to the diagnosis and treatment of PD.

Neuroticism, agreeableness and to some extent extroversion can be used to understand PDs.
- PDs can be described and understood in the context of the five factor model rather than viewing them as separate from our understanding of normal personality.

Question 18

PDs and personality trait theory - Widiger and Mullins (2003)

Answer 18

provide a descriptive table summarising various associations between personality trait facets and the ten PDs.

• Each personality disorder has a unique pattern of associations with facets of the five superfactors:
  
  • high anger/hostility (Neuroticism factor) and low trust, straightforwardness and compliance (Agreeableness factor) is associated with Paranoid PD.
  • high anxiousness, angry hostility, depressiveness, impulsivity and vulnerability (Neuroticism factor) along with low trust and compliance (Agreeableness factor) are all associated with Borderline PD.
• High scores on one or more of the facets of neuroticism are associated with each of the personality disorders except for schizoid personality disorder.
  
  • Schizoid PD is better defined by low scores on three facets of Extroversion (warmth, gregariousness, positive emotionality) and by low scores on one facet of Openness (feelings).

Question 19

PDs and personality trait theory - Saulsman and Page (2004)

Answer 19

conducted a meta-analysis on data from 15 independent samples to examine the relationship between the five-factor model of personality and each of the ten Personality Disorders.

• Three of the five broad superfactors, neuroticism, agreeableness and to a lesser extent extroversion, have the strongest associations with personality disorders.
• All personality disorders were best defined by the dimensions of high neuroticism and low agreeableness except for Dependent PD which was best defined by high neuroticism and high agreeableness.
• Extroversion was related to most personality disorders but some disorders involve high extroversion (e.g., histronic PD) and others low extroversion (avoidant PD).

Question 20

the Psychopathology-Five (PSY-5)

Answer 20

alternative framework to that measured by the NEO-PI-R – better measure

• PSY-5 is derived from the Minnesota Multiphasic Personality Inventory (MMPI) (personality measure used in clinical settings).
• The PSY-5 was developed to measure five dimensions of personality that reflect psychopathology (Harkness, McNulty, & Ben-Porath, 1995).
• The five factor model and the PSY-5 share three similar factors:
  
  1. Agreeableness/aggression,
  2. Extraversion/introversion,
  3. Neuroticism/negative
     emotionality.
• Two further dimensions of the PSY-5:
  
  4. Disconstraint (delinquent behaviours and norm violation)
  5. Psychoticism (psychotic beliefs)

The PSY-5 is better than the NEO-PI-R and the MMPI at predicting personality dysfunction and for predicting extreme violence and impulse control disorders.
- Aggression factor of PSY-5 assesses more extreme behaviour than the agreeableness factor of the NEO and might be better suited to identifying a violent psychopath whose behaviour is much more extreme than disagreeableness.

An adolescent version of the PSY-5 has been developed and research suggests that its usefulness for assessing personality dysfunction in adolescents is comparable to the original adult version (Bolinskey et al., 2004).
- The existence of the same dimensions in adolescents underlines the view that personality dysfunction has its roots in childhood and that the detection of a personality disorder in adulthood is likely a reflection of this.

Question 21

are PDs treatable?

Answer 21

Personality disorders are difficult to treat because they involve deeply rooted patterns of thoughts, feelings and ways of relating to others.

• Individuals with a personality disorder are often reluctant to seek help and resistant to therapeutic input.
• Some therapists are reluctant to work with individuals with a personality disorder because of resistance to change and resistance to the therapeutic process.
• Depends on the disorder and the individual
• Some severe personality disorders (e.g., psychopathy) remain resistant to treatment.
  
  • Psychopaths are particularly adept at ‘faking good’.

Some of the milder forms of personality disorders including BPD, OCPD, APD and dependent personality disorder are easier to treat than others.

• Some symptoms respond better to treatment than others.
• Some cognitive-behavioural processes are more responsive to treatment than others – we will be returning to this next week when we consider the ‘transdiagnostic approach’.

Question 22

are people with PDs dangerous?

Answer 22

The majority of people diagnosed with a personality disorder are not dangerous or violent.

Occasions when violence does occur tend to involve people diagnosed with Antisocial Personality Disorder (APD).

• Psychopathy is a concept related to APD. People with a diagnosis of psychopathy may be more likely to be violent.
• Childhood trauma may lead to difficulties with emotional regulation, impulsivity and empathy, which may lead to violence or anti-social behaviour and also underlie personality disorder.